Full report pd 2013 g5 1 by Juliana Shaibun

DESIGN OF GAHARU OIL EXTRACTION PLANT WITH CAPACITY OF 450L PER ANNUAL Kundang, Rawang, Selangor

Plant Owner: Dr Liza Md. Salleh Assoc. Prof. Dr. Fadzilah Adibah Consultant Engineers: Koo Suet Ching Juliana Bt. Shaibun Noor Salbaniah Bt. Jalaluddin Rafiqqah Bt. Mohamad Sabri Mohd. Syamsul Fitri Bin Saad

SKF 4824-01 DESIGN PROJECT Design of Gaharu Oil Extraction Plant with Capacity of 450L per Annual

PROJECT DESIGN TEAM 5 4SKB Koo Suet Ching

(890530-07-5702)

Juliana Binti Shaibun

(890407-26-5068)

Mohd Syamsul Fitri Bin Saad

(890428-03-5843)

Rafiqqah Mohamad Sabri

(901202-13-6300)

Noor Salbaniah Binti Jalaluddin

(900923-07-5662)

Supervisor: Dr. Liza Bt. Md Salleh Co-supervisor: Prof. Madya Dr. Fadzilah Adibah Bt. Abdul Majid

TIMBERCHEM CHEMICAL CONSULTANCY SDN.BHD. UniversitiTeknologi Malaysia 81310, Johor Bahru, Johor From : Dr. Liza Md. Salleh, Plant Manager, Timberchem Chemical Consultancy Sdn. Bhd.

28th February 2013

To : Plant Design Team, Process Engineering and Design Department Timberchem Chemical Consultancy Sdn. Bhd. Dear Madam, Design of Gaharu Essential Oil Extraction Plant with Capacity of 450L per Annual World demand for gaharu essential oil is forecasted to grow during this period commonly used and yet extremely valuable. Gaharu oil are used for the manufacture of medicine, perfume and incense. Since there is great market demand for gaharu essential oil, I am commissioning this project to your design team to design gaharu essential oil extraction plant with the capacity of 450L per annual in the most profitable way. Many methods have been developed in producing gaharu essential oil but most have been abandoned for economic or environmental reasons. A series of tasks consisting of determining the most suitable process to produce gaharu essential oil, project feasibility study, site study and to propose a preliminary plant design including process description, synthesis of process flow diagram, mass and energy balances, individual equipment optimization, heat integration, equipment sizing and costing. Detailed chemical and mechanical design of equipments, process control and safety study, waste treatment for environment protection and economic analysis should also be carried out. I hope your design team could come out with a suitable plant design to produce gaharu essential oil in the most profitable way.

Yours truly,

……………………. Dr. Liza Md. Salleh, Plant Manager, Timberchem Chemical Consultancy Sdn. Bhd. i

Timberchem Chemical Consultancy Sdn. Bhd.

DESIGN OF GAHARU OIL EXTRACTION PLANT WITH CAPACITY OF 450L PER ANNUAL

For DR. LIZA MD. SALLEH Supervisor PROF. MADYA DR. FADZILAH ADIBAH BINTI ABD MAJID Co-Supervisor

Prepared by: KOO SUET CHING NOOR SALBANIAH BT. JALALUDDIN RAFIQQAH BT. MOHD SABRI JULIANA BT. SHAIBUN MOHD. SYAMSUL FITRI BIN SAAD

Process Design Team 5 (4SKB),

Timberchem Chemical Consultancy Sdn. Bhd.

3th JUNE 2013

ACKNOWLEDGEMENT

We wish to express our deepest gratitude to our supervisor, Dr. Liza Bt. Md Salleh and also the Design Project Coordinator, Dr. Eraricar bte Salleh for their tireless effort and on-going support, advice as well as guidance, without those help, our report would not have been completed successfully.

We also would like to extend our heartfelt gratitude to Prof. Madya Dr. Fadzilah Adibah, our co-supervisor who never fails to give much needed advice and guidance throughout the project. To all of our friends and seniors who cared to offer needed tips, advice and endless cooperation, words of thanks would never be enough.

Finally, we hope that this report will give the readers some insight as to the maze of activities associated with the construction of a gaharu oil extraction plant - from its planning stages until it is ready for start-up and commissioning.

iii

TABLE OF CONTENTS

CHAPTER

TITLE

PAGE

LETTER OF TRANSMITTAL

TITLE PAGE

ACKNOWLEDGEMENT

iii

TABLE OF CONTENTS

LIST OF FIGURE

LIST OF TABLE

xviii

LIST OF NOMENCLATURE

xxi

EXECUTIVE SUMMARY

xxvii

1. INTRODUCTION

1.1 Process Background

1.1.1

Introduction to Gaharu

1.1.2

Distribution of resin in the wood

1.1.3

Colour and Scent

1.1.4

Causes of Formation, Age and Location in a Tree

1.1.5

Size and Form

1.1.6

Source and Scarceness

1.1.7

Grading of Gaharu

1.1.8

Uses of Gaharu

8 iv

1.1.9

Overview of Malaysia Agarwood

1.1.10 Overview of Essential Oil

1.1.11 Overview of Gaharu Essential Oil

1.2 Market Survey

1.2.1

Survey on Estimate Cost of Cultivation Gaharu

1.2.2

Survey of Gaharu Distribution

1.2.3

Local market

1.2.4

Global Market Demand

1.2.5

Asian and Middle East Market

1.2.5.1

Taiwan Market Demand

1.2.5.2

Japan Market Demand

1.2.5.3

Middle East Market Demand

1.2.6

Survey on Price Trends

1.2.7

Gaharu Trade

1.2.7.1

Forms of Gaharu in Trade

1.3 Project Feasibility and Site Survey

1.3.1

Malaysian Economic Situation

1.3.2

Criteria of Plant Site Selection

1.3.3

Overview of Several Strategic Sites in Malaysia

1.3.4

Site Study

1.3.5

Decision Site

1.3.6

Proposed Plant Layout

1.4 Review of Physical and Chemical Properties Data

1.4.1

Physical Properties of Essential Oil

1.4.2

Physical properties of component in Gaharu

essential oil 1.4.3

Chemical Properties of Essential Oil

1.4.4

Structure and Chemical Compound of Gaharu

46 v

1.5 Process Screening for Extraction Methods of Agarwood Oil 1.5.1

Distillation

54 54

1.5.1.1

Introduction

1.5.1.2

Principles of Distillation

1.5.1.3

Methods for Distillation

1.5.2

Extraction of Gaharu Essential Oil via Hydro distillation

(Alternative 1) 1.5.2.1

Introduction

1.5.2.2

Process and Structure

1.5.2.3

Traditional Method of Producing Attar Using

Hydrodistillation 1.5.2.4

Advantage of Hydrodistillation

1.5.2.5

Disadvantages of Hydrodistillation

1.5.3

Extraction of Gaharu Essential Oil via Water and Steam

Distillation (Alternative 2) 1.5.3.1

Introduction

1.5.3.2

Process and Structure

1.5.3.3

Disadvantages of Water and Steam Distillation

1.5.3.4

Advantages of Water and Steam Distillation

over Water Distillation 1.5.3.5 1.5.4

Improved Field Distillation Units

Extraction of Gaharu Essential Oil via Direct Steam

71 72

Distillation (Alternative 3) 1.5.4.1

Introduction

1.5.4.2

Process and Structure

1.5.4.3

Advantages of Direct Steam Distillation

1.5.4.4

Disadvantage of Direct Steam Distillation

1.5.5

Extraction of Gaharu Essential Oil via Cohobation

Distillation (Alternative 5) 1.5.5.1

Introduction

76 vi

1.5.6

Extraction of Gaharu Essential Oil via Supercritical

Fluid Extraction (Alternative 6) 1.5.6.1

Introduction

1.5.6.2

Supercritical Fluid

1.5.6.3

Modifiers or co-solvents

1.5.6.4

SFE Process

1.5.6.5

Major advantages of SFE technique

1.6 Enhancement of Essential Oil from Agarwood 1.6.1

Parameters Affecting Yield and Quality of Essential Oils

85 85

1.6.1.1

Mode of Distillation

1.6.1.2

Proper Design of Equipment

1.6.1.3

Material of Fabrication of Equipment

1.6.1.4

Condition of Raw Material

1.6.1.5

Time for Distillation

1.6.1.6

Loading of Raw Material and Steam Distribution

1.6.1.7

Operating Parameters

1.6.1.8

Condition of Tank and Equipment

1.6.1.9

Purification of Crude Essential Oils

1.6.1.10

Continuous Steam Distillation

1.6.2

Pretreatment

1.6.3

Soaking

1.6.3.1

Enzymatic Pretreatment

1.6.3.1.1

Introduction

1.6.3.1.2

Methodology

1.6.3.1.3

Enzymatic Process

1.6.3.1.4

Advantages and Disadvantages of Enzymatic

Pretreatment 1.6.3.2

Ultrasonic

1.6.3.2.1

Introduction

96 96

vii

1.6.3.2.2

Principles and Mechanisms of

Sonication-assisted Extraction 1.6.3.2.3

Effects of ultrasound characteristics

1.6.3.2.4

Operating conditions

1.6.3.2.5

Advantages and disadvantages of

sonication-assisted extraction 1.6.3.2.6

Potential applications of sonication-assisted

extraction 1.6.3.2.7

The Role of Ultrasonicas Physical Treatment

100

of Raw Materials

2. PROCESS SYNTHESIS AND FLOW SHEETING 2.0 Synthesis of Process Flow Diagram

102 102

2.0.1

Process Flow Diagram

102

2.0.2

Process Description

103

2.1 Basis for Equipment Selection

106

2.1.1

Mixing Tank with Impeller

107

2.1.2

Autoclave

110

2.1.3

Cooler

112

2.1.4

Incubator

114

2.1.5

Steam Extraction Unit

116

2.1.6

Condenser

119

2.1.7

Boiler

121

2.1.8

Oil Water Separator

124

2.2 Manual Material and Energy Balance

125

2.2.1

Manual Calculation for Material Balance

125

2.2.2

Manual Calculation of Mass Balance

127

2.2.2.1

Mixing Tank

131

2.2.2.2

Autoclave

133 viii

2.2.2.3

Cooler

134

2.2.2.4

Incubator

135

2.2.2.5

Condenser

138

2.2.2.6

Boiler

139

2.2.2.7

Extraction Unit

140

2.2.3

Manual Calculation for Energy Balance

142

2.2.3.1

Autoclave

144

2.2.3.2

Incubator

145

2.2.3.3

Extraction Unit

147

2.2.3.4

Boiler

150

2.2.3.5

Condenser

151

3. PROCESS ENERGY INTEGRATION

156

3.1 Introduction

156

3.2 Stream Data Extraction

157

3.3 Pinch Technology

158

3.4 Problem Table Algorithm

160

3.5 Maximum Energy Recovery (MER)

165

3.6 Feasibility of Stream Matching

165

3.7 Comparison of Energy Consumption Before and After

167

Heat Integration 3.8 Conclusion

4. WASTE MANAGEMENT

169

171

4.1 Introduction

171

4.2 Guidelines for Environment Protection (ISO 14001-

172

Environment Management System) 4.3 Sources of Waste

173

4.4 Waste Management

175 ix

4.2.1

4.2.2

Solid Waste Management

175

4.4.1.1 GaharuPellets

175

4.4.1.2 GaharuJoss Stick

177

Waste Water Treatment

179

4.4.2.1 Screening of Alternative Waste Treatment

179

Processes 4.4.2.2 Selection of Process

181

4.4.2.3 Process Description

181

4.4.2.4 Material Balance for Waste Treatment Plant

183

4.4.2.5 Kinetics of Bacterial Growth

187

4.4.2.6 Sizing and Costing of Waste Treatment

187

Equipment 4.4.2.7 Costing for Sludge Disposal

4.3 Conclusion

5. EQUIPMENT SIZING AND COSTING

198

200

5.1 Introduction

200

5.2 Sizing and Costing

200

5.2.1

Sizing and Costing of Grinder

201

5.2.2

Sizing and Costing of Mixing Tank

203

5.2.3

Sizing and Costing of Storage Tank

207

5.2.4

Sizing and Costing of Autoclave

209

5.2.5

Sizing and Costing of Incubator

213

5.2.6

Sizing and Costing of Oil Water Separator

216

5.2.7

Sizing and Costing of Extraction Unit

219

5.2.8

Sizing and Costing for Pump

222

5.2.9

Sizing and Costing of Cooler

227

5.2.10 Sizing and Costing for Condenser

231

5.2.11 Sizing and Costing of Boiler

233

6. PROCESS CONTROL

236

6.1 Introduction

236

6.2 Control System Design

239

6.3 Hardware Elements Of A Control System

241

6.4 General Type of Control Configuration

243

6.4.1

Feed-Forward Control

243

6.4.2

Feedback Control

244

6.4.3

Inferential Control Configuration

245

6.4.4

Cascade Control

246

6.4.5

Ratio Control

248

6.5 Typical Control System

248

6.5.1

Level Control

248

6.5.2

Pressure Control

249

6.5.3

Flow Control

251

6.5.4

Cascade Control

252

6.5.5

Temperature Control

253

6.5.6

Ratio Control

253

6.6 Process and Instrumentation Diagram

253

6.7 Process Control System in Gaharu Essential Oil Plant.

252

6.7.1

Control System for the Cooler, P-4/ HX-101

255

6.7.2

Control System for the Pump, PM-101

256

6.7.3

Control System for the Condenser, P-8/ HX-101

257

6.7.4

Control System for the Autoclave

258

6.7.5

Control System for the Incubator

259

6.7.6

Control System for the Boiler

260

6.7.7

Control System for the Distillation still

261

6.8 Conclusion

7. PROCESS SAFETY STUDY

263

265

7.1 Introduction

265

7.2 General Plant Safety

267

7.2.1

Chemical Storage and Process Vessels

267

7.2.2

Transportation

268

7.2.3

Housekeeping

269

7.2.4

Utility

270

7.3 Worker Safety

271

7.3.1

General Personnel Safety

271

7.3.2

Personal Protective Equipment

272

7.3.2.1 Safety Hats

273

7.3.2.2 Face Shields

273

7.3.2.3 Goggles

273

7.3.2.4 Air Mask

274

7.3.2.4 Safety Footwear

275

First Aid

275

7.3.3

7.4 Fire Hazards

276

7.4.1

Fire Prevention and Safety Procedures

276

7.4.2

The Plant Progress

280

7.5 Emergency Response

280

7.5.1

Emergency Control Center

282

7.5.2

Fire Alarms and Declaring Emergency

282

7.5.3

Fire Protection

283

7.5.4

Label and Signs

283 xii

7.6 Leakage Prevention

284

7.6.1

Control of Leaks

285

7.6.2

Detection of Leaks

286

7.6.3

Leaking Protective Equipment

287

7.7 Active Protective Systems

287

7.8 Monitoring For Safety

288

7.9 Material Safety Data Sheet (MSDS)

289

7.10 HAZOP Study

290

7.10.1 What is HAZOP

290

7.10.2 The Objectives of HAZOP

291

7.10.3 Hazard and Operability Studies

291

7.10.4 Basic Principles of HAZOP Studies

293

7.10.5 HAZOP Procedure

294

7.10.6 HAZOP Study on Various Operation Units

295

7.10.7 HAZOP Studies on the Selected Equipments

295

7.10.7.1

HAZOP Studies on Reactor

296

7.10.7.2

HAZOP Studies on Distillator

299

7.10.7.3

HAZOP Studies on Heat Exchangers Unit

301

7.10.7.4

HAZOP Studies on Tanks

305

7.10.7.5

HAZOP Studies on Mixer

306

7.11 Site and Plant Layout

307

7.11.1 Site Layout

307

7.11.2 Plant Layout

309

7.12 Consideration of Plant Start-up and Shut Down

310

7.12.1 Plant Start-up

310

7.12.2 Plant Shut Down

313 xiii

7.12.3 Unplanned Shut-Down

317

7.12.4 Emergency Shutdown

318

7.12.5 Start-up and Shutdown for Major Equipment

320

7.12.6 Clearance for Maintenance

321

MECHANICAL DESIGN OF MAJOR EQUIPMENT

323

8.1 Introduction

323

8.2 Equipment Specification Sheet

324

8.3 Mechanical Design of Autoclave

324

8.4 Mechanical Design of Extraction unit

327

8.5 Mechanical Design of Incubator

329

8.6 Mechanical Design of Condenser

332

PROFITABILITY ANALYSIS

357

9.1 Introduction

357

9.2 Gross Root Capital

358

9.3 Fixed and Total Capital Investment Cost

360

9.4 Manufacturing Cost

363

9.4.1

Estimation of Operating Labor Cost

363

9.4.2

Estimation of Utilities Cost

364

9.5 Cash Flow Analysis

368

9.6 Conclusion

376

10 CONCLUSION AND RECOMMENDATION

377

10.1 Conclusion

377

10.2 Recommendations

379

REFFERENCES xiv

LIST OF FIGURE

TITLE

PAGE

1.1

Cross section of Gaharu tree

1-1

1.2

Gaharu Chip

1-11

1.3

Plantation of Gaharu in Malaysia

1-18

1.4

Trends in the price of top grade gaharuwood chips on sale in

1-20

Malaysia (1880-2000) 1.5

Site Layout for Production of Gaharu Essential Oil

1-38

1.6

Chemical structures

1-48

1.7

Chromatogram revealing constituents in 6-month old induced Gaharu

1-49

1.8

Structures of compound from Gaharu oil

1-53

1.9

Major constituent genkwanin 5-O-b-primeveroside compound

1-54

that caused mild laxative effect in mice

1-38

1.10

Hydro distillation process.

1-59

1.11

Hydro distillation process in extracting Gaharu essential oil

1-62

1.12

Hydro distillation is conventional method used in India.

1-64

1.13

Local type field distillation unit in India

1-68

1.14

Water and Steam Distillation Process

1-69

1.15

CIMAPâ&#x20AC;&#x;s improved field distillation unit

1-72

1.16

Direct Steam Distillation Process

1-73

1.17

Boiler-operated steam distillation unit

1-75

1.18

SFE Process

1-82

1.19

Extraction yield versus at different temperatures

1-83

2.1

Extraction of Gaharu Essential Oil with Capacity of 450 Litres per Year

2-105

2.2

Mixing tank with impeller

2-107

2.3

Mixing - Axial flow and radial flow

2-108

2.4

Autoclave

2-110

2.5

Illustration of steam-pressure sterilizer

2-112

2.6

Cooler

2-112

2.7

Shell and tube heat exchangers

2-117

2.8

Shell and Tube Cooler

2-114

2.9

Incubator

2-114

2.10

Process of incubator

2-116

2.11

Illustration of Incubator

2-116

2.12

Steam Distillation

2-117

2.13

Cross Section of Steam Distillation

2-118

2.14

Steam Distillation Still

2-118

2.15

Condenser

2-119

2.16

Process of surface condenser

2-120

2.17

Illustration of Condenser

2-120

2.18

Fire-tube Type Steam Boiler

2-123

2.19

Oil Water Separator

2-124

2.20

The Cutaway Section of Oil Water Separator

2-125 xvi

3.1

Determinations of Heat Intervals, ď &#x201E;Hinterval

3-162

3.2

Heat Cascade

3-163

3.3

Composite Curve

3-164

3.4

Stream Matching Below Pinch

3-165

3.5

Matching of Stream 3 with 10

3-166

3.6

Process Flow Diagram after Energy Integration

3-170

4.1

Gaharu pellet

4-177

4.2

Giant Dragon Joss Stick

4-178

4.3

The Spiral Joss Stick

4-178

4.4

Biological Treatment with Activated Sludge System

4-183

6.1

Typical close loop control system

6-241

6.2

Feed-Forward Control Concepts

6-244

6.3

Feedback Control Concepts

6-245

6.4

General Structure of Inferential Control Configuration

6-246

6.5

Cascade Control Block Diagram

6-247

6.6

Level Control.

6-249

6.7

Pressure control

6-250

6.8

Flow control

6-252

6.9

Piping and Instrumentation Diagram (P&ID)

6-264

7.1

The flow sheet of HAZOP Procedure

7-294

8.1

Mechanical Drawing of Autoclave

8-326 xvii

8.2

Mechanical Drawing of Extraction unit

8-328

8.3

Mechanical Drawing of Incubator

8-331

8.4

Mechanical Drawing of condenser

8-334

9.1

Cumulative Annual Cash Flow Profile

9-371

9.2

Cumulative Discounted Annual Cash Flow

9-374

xviii

LIST OF TABLES

TABLE

TITLE

PAGE NO.

1-1

Prices for Gaharu chips sold in Malaysia (MYR/kg)

1-7

1-2

Gaharu Price per Kilogram in May 2001

1-8

1-3

Gaharu Producing Species of Aquilaria in Peninsular Malaysia

1-9

1-4

Gaharu producing species in the family Thymelaeaceae

1-12

1-5

Gaharu Grade

1-13

1-6

Main Gaharu producing areas and number of harvesters in 1-33 Peninsular Malaysia

1-7

Comparison of short-listed of the potential site location

1-37

1-8

Phenol compounds present in the induced gaharu products

1-52

2-1

Plant Equipment and Its Functions

2-106

2-2

Differences between Propeller Mixer, Turbine Mixer and Paddle 2-108 Mixer

2-3

Pressure-Temperature-Time Relationship in Steam-Pressure 2-111 Sterilization

2-4

Differences between Fire-tube Boiler and Water Tube Boiler

2-121

2-5

Summary of Mass Flow Rate for Each Stream

2-141

2-6

Summary of Molar Flow Rate for Each Stream

2-142

xix

2-7

Summary Enthalpy for Each Stream

2-154

2-8

Summary Heat Duty for Each Unit Operation

2-155

3.1

Summary of Hot and Cold Streams from Simulated Results

3-158

3.2

Shifted Temperature for the Hot and Cold Streams in Pinch 3-161 Technology

3.3

Comparison between the Energy Consumption Before And After 3-167 Heat Integration

4.1

Types of Equipment That Produce Waste.

4-174

4.2

Summary of Equipment Sizing in Wastewater Treatment Plant

4-196

4.3

Summary of Equipment Costing in Wastewater Treatment Plant

4-196

4.4

Summary Sheet of Wastewater Treatment Plant

4-197

4.5

Summary of Costing for Waste Treatment

4-198

5.1

Specification sheet for mixing tank, V-101

5-206

5.2

Specification sheet for storage tank, V-101

5-209

5.3

Specification sheet for autoclave, V-102

5-212

5.4

Specification sheet for incubator, V-103

5-216

5.5

Specification sheet for oil water separator, V-105

5-219

5.6

Specification sheet for extraction unit, V-104

5-222

5.7

Summary of Sizing and Costing for Pump, PM-101

5-226

5.8

Specification sheet for cooler, HX-101

5-230

5.9

Specification sheet for condenser HX-102

5-233

5.10

Specification sheet for boiler, V-104

5-235

6.1

Basic Symbols Used To Show the Valves, Instrument and 6-254 Control Loops

7.1

Frequently Used Term and Their Definitions

7-266

7.2

HAZOP Guide Words

7-293

7.3

HAZOP Study on Reactor – Reaction

7-296

7.4

HAZOP Study on Reactor - Flow

7-297

7.5

HAZOP Study on Reactor - Temperature

7-298

7.6

HAZOP Study on Reactor - Pressure

7-299

7.7

HAZOP Studies on Distillator– Pressure

7-299

7.8

HAZOP Studies on Distillator– Temperature

7-300

7.9

HAZOP Study on Heat Exchanger - Flow rate

7-301

7.10

HAZOP Study on Heat Exchanger - Pressure

7-303

7.11

HAZOP Study on Heat Exchanger - Temperature

7-304

7.12

HAZOP Studies on Storage Tank.

7-305

7.13

The HAZOP study for mixer is flow rate control.

7-306

8.1

Mechanical Design Summary for Autoclave, V-102

8-325

8.2

Mechanical Design Summary for Extractor Vessel, V-104

8-327

8.3

Mechanical Design Summary for Incubator Tank, V-103

8-329

8.4

Mechanical design specification sheet of condenser, HX-102

8-332

9.1

Capital Cost Summary

9-359

xxi

9.2

Total Fixed Capital and Total Capital Investment

9-362

9.3

Operating labor estimation

9-363

9.4

Manufacturing Cost Summary

9-366

9.5

Manufacturing Cost Summary (Continue)

9-367

9.6

Undiscounted Cash Flow Analysis

9-370

9.7

Discounted Factor Cash flow Analysis for 10 % & 15 %

9-372

9.8

Discounted Factor Cash flow Analysis for 20 % & 30 %

9-373

9.9

Summary of Cash Flow Analysis for Various Interests

9-375

xxii

TABLE OF NOMENCLATURE

PNG

Papua New Guinea

MYR

Malaysian ringgit

CO2

Carbon dioxide

FRIM

Forest Research Institute Malaysia

CITES

Convention on International Trade in Endangered Species

USD

United State Dollar

UAE

United Arab Emirates

FDI

Foreign Direct Investment

AFTA

ASEAN Free Trade Area

IMP2

Malaysiaâ&#x20AC;&#x;s Second Industrial Master Plan

R&D

Research and Development

DOE

PKNS

PerbadananKemajuanNegeri Selangor

PKNP

PerbadananKemajuanNegeri Perak

JCORP

Johor State Economic Development Corporation

SAJ

Syarikat Air Johor Berhad

LMT

Lumut Maritime Terminal SdnBhd

SIP

Segamat Inland Port

ITA

Investment Tax Allowance xxiii

EXECUTIVE SUMMARY

Gaharu is one of the most precious trees in the world. It is one of the most expensive natural products existing today. The main regions of gaharu plantation are in Bangladesh, Bhutan, India, Indonesia, Malaysia, Myanmar, Philippines, Singapore and Thailand. In Malaysia, chips, flakes, oil and powder waste after extraction are the most common forms traded. The objective of this project is to set up a gaharu essential oil extraction plant with an annual capacity of 450L.

Gaharu oil have a wide use in medicine (general pain reducer, dental pain, kidney and rheumatism medicine), as venom repellent, in perfume and as incense raw material. It plays roles in traditional Chinese medicine for its sedative, carminative, and anti-emetic effects, and also as incense for religious ceremonies.

The selected plant location is in Kulai Johor. The cost of transportation can be reduced by minimizing the distance of the plant and the plantation. Meanwhile this location is strategic because it is situated near to Kulai City which is readily available of manpower supply. Furthermore, electrical supply and water supply facilities are also contributed for the site decision. The transportation facilities include the railway also support to our selection.

The extraction method used is steam distillation where it yield high conversion of raw material to product, the amount of steam can be readily controlled, no thermal decomposition of oil constituents and it is the most widely accepted process for largescale oil production.

xxiv

At base case, process flow diagram (PFD) was designed. The manual calculation was used in order to get the overview of process synthesis. This manual calculation was based on short-cut method. For simulating the process, we used SuperPro software to maximize the process performance and optimization.

Wastes produced in the plant include solid and liquid waste. The solid waste can sell and turns into useful product like joss sticks and gaharu pallet which are profitable to the company. A waste water treatment plant is built which contains 5 major equipments in waste treatment process which are pumps, clarifier, filter press, aeration tank, and equalization tank. The effective waste water treatment ensure effluent of the plant safe to be discharge and do not cause hazard to the environment.

Equipment sizing and costing is carried out in order to estimate the cost that we need for setting the plant. This information is very important to carry out the feasibility studies based on economic point of view. So, we design the equipment which is enough to support the production as well as lower the cost. Besides, the specific mechanical design is also done based on the process requirements. Safety analysis such as HAZOP studies and control system are carried out in order to ensure the safety and overall control of the plant.

At the end of this proposal, we do the economic analysis of this project whether it is worth or not to construct this plant. From the result of the analysis, we got the quite high rate of return 55.17%. The payback period is estimated of 2.8 years after 3 years of start-up period. Based on the overall plant economic evaluation, it can be concluded that this gaharu oil extraction production plant is indeed economically feasible and thus provide promising return on investment.

xxv

CHAPTER 1

INTRODUCTION

1.1 Process Background

1.1.1 Introduction to Gaharu

Gaharu is one of the most precious trees in the world. It is one of the most expensive natural products existing today. Gaharu or it scientific named Aquilaria malaccensis. Gaharu is also known as Agarwood, eaglewood, aloeswood, oud, chenxiang, and jingkoh - these are just a few of the names for the resinous, fragrant and highly valuable heartwood produced by Aquilaria malaccensis and other species of the Indomalesian tree genus Aquilaria. Aquilaria malaccensis is one of 15 tree species in the Indomalesian genus Aquilaria, family Thymelaeaceae. It is a large evergreen tree growing up to 40 m tall and 1.5-2.5 m in diameter, found typically in mixed forest habitat at altitudes between 0 and 1000 m above sea level. It gives off a unique aromatic scent when the wood is burnt. There are no less than twenty names associated with it, and this reflects its long history and widespread usage. Some of these names include

agaru, aloes wood, eagle wood, oud, chen-xiang, jinkoh and so on depending on the region.

(a)

(b)

Figure 1.1: Cross section of Gaharu tree.

Figure 1.1 (a) shows a cross section of a Gaharu tree that was wounded but not treated is shown in the photo. This control tree shows clear white wood and no Gaharu formation when it was cut 17 months after wounding. While figure 1 (b) shows a relatively large area of dark resinous wood can be seen within the tree. The highest concentrations of resin occur at the edges of the dark zone.

Gaharu is divided into several grades in the market. The best and darkest are used in incense mixtures while the lower grades are extracted by hydrodistillation to produce Gaharu

oil used in perfumery. Gaharu is the resinous wood of

the Aquilaria tree. Neither wild nor cultivated Aquilaria trees can form Gaharu without wounding induced by external factors such as physical injury, insect gnawing, or microbial infection. In addition, an Aquilaria tree takes several years to form Gaharu around the wound. Gaharu plays roles in traditional Chinese medicine for its sedative, carminative, and anti-emetic effects, and also as incense for religious ceremonies.

Further, Gaharu essential oil is the most important ingredient in high-end perfumes because of its unique fragrance.

The species has a wide distribution, being found in Bangladesh, Bhutan, India, Indonesia, Malaysia, Myanmar, the Philippines, Singapore and Thailand. Species in the genus Aquilaria from the family Thymelaeaceae are reported to produce Gaharu or Gaharu. The grade of Gaharu is divided by 5 types, which are Grade Super A, A, B, C, and D. Throughout the range states (producer countries), there are 25 species of Aquilaria and 15 species are reported to form Gaharu . But only A. malaccensis (syn. A. agallocha) and A. crassna are more frequently associated with agarwood or Gaharu . Gaharu has also been reported from species in several other genera within the same family. In the Malaysian forests, the main species producing Gaharu is A. malaccensis or karas as it is commonly known. As part of an on-going research on the chemical profiling of some Malaysian Gaharu oils and evaluation of their potential beneficial properties; Gaharu oils obtained from different sources in Peninsular Malaysia were analysed by chromatographic methods and reported.

1.1.2

Distribution of resin in the wood

The higher resin content of Gaharu piece has, the higher the price. High resin content allows wood pieces to produce a purer or higher-level scent as well as provide greater therapeutic effect. The most common method of grading is to place Gaharu pieces into water, and then the pieces are classified into three basic grades: sinking, halfsinking (or half-floating) and floating. Sinking pieces are top grade and the rest are divided into different grades based on diverse standards, including the pattern of resin

distribution in each piece. Higher resin content also gives an Gaharu piece more weight than others in similar size.

„Floating‟ pieces are more common in Taiwan than „sunken‟ pieces because they are less expensive. Burning a small sample of the Gaharu is the most popular method of further determining the grade of „sunken‟ or „floating‟ pieces, since resin can be seen to exude with a bubble-like appearance when the wood is burnt. Many traders also stated that Gaharu grading is very subjective, meaning that it takes years of experience to learn to distinguish accurately between different types and grades of Gaharu (Chim-Hyang Corporation, in litt. To TRAFFIC Southeast Asia, 2004).

1.1.3

Colour and Scent

A number of traders who specialize in high-grade Gaharu

indicate that

agarwood from different countries/islands of origin contains distinctive resin coloration. It is said that the colour of resin that an Gaharu

piece holds is the main factor

determining its scent when it is burnt. The colours mentioned include: green, dark green, yellow, golden, red (purple), black, brown, and white. The darker an Gaharu piece, the higher resin content and therefore the higher grade (i.e. sinking in water plus dark colour) (Barden et al, 2000; Song, 2002).

In the general retail market, most traders (retailers) explained that scent is the major factor influencing a consumer‟s decision. In general, Gaharu

materials and

products producing a softer scent are considered as higher grade, are more popular and are sold at higher prices in Taiwan than those producing a more intense scent. There are 4

no systematic indicators that demonstrate a uniform relation between colour, scent, grading and pricing.

1.1.4

Causes of Formation, Age and Location in a Tree

Gaharu raw materials extracted from dead trees buried in the ground or from a swamp are generally considered more „mature‟ material, which can contribute to higher grading and higher prices than Gaharu extracted from a standing tree. When comparing Gaharu taken from different parts of the same tree, Gaharu from the roots is considered higher grade than Gaharu from higher parts of a tree.

1.1.5

Size and Form

For Gaharu pieces, when two pieces are at a similar level of grade according to other characteristics, the value of the larger piece could be many times more than the ratio between the pieces‟ respective weights. Gaharu pieces that have natural shapes of aesthetic value are usually picked out by traders to be sold at higher prices to Gaharu („art‟) collectors.

1.1.6

Source and Scarceness 5

Gaharu items from sources known to have increasingly scarce supplies, such as those from Vietnam, are sold at much higher price than other items of similar grade.

1.1.7

Grading of Gaharu

There are various systems adopted for Gaharu grading. Many traders claim that each country (of origin or import) has its own Gaharu grading system, but there is no record of a systematic explanation of these systems. As noted by Barden et al., grading Gaharu is a complicated process. This includes evaluating the size, colour, odour, weight (on scale and in water) and flammability of the wood but application of grades codes (Super A, A, B, C, D, E) varies between buyers in PNG.

A low grade does not always equate a low price, since low resin content could be made up for by an attractive shape. Conversely, a high grade may actually be sold very cheaply if its colour or texture is masked by low-grade wood that has yet to be scraped off. As an example, mixed chips of good quality (black, black and brown) are graded as C and often sold a higher price per gram than large pieces of A and B grade. Indicative prices reported for Gaharu sold in Malaysia are presented in Table 1.1 (below).

Table 1.1: Prices for Gaharu chips sold in Malaysia (MYR/kg) Grade

Year 1914a

Double

1992b

1999c

2003d

2004e

11.19

2005f 12000

super Super A high

10000 4.66

A low B high

B low C 1 high

1.02

790

4000

5000

530

3200

3000

530

2500

2000

6000

4000

400

1800

1500

5000

3000

260

800

1000

5000

2000

400

500

100

C 1 low C 2 high

0.51

C 2 low

8000

8000 4000

1000

D high

0.24

250

D low

0.12

Source: a – Federated Malay States (Anon., 1914); b – Peninsular Malaysia (Lim, 1992); c – Terengganu (Lim et al., 2003); d – Hulu Perak (Lim et al., 2003); e – Johor (Anon., 2004l); f – Kelantan (Dahlan, 2005). Note: The grades presented here have not been standardised. According to Zich et al., price per kilogram in May 2001 averaged as follows in Table 1.2. 7

Table 1.2: Gaharu Price per Kilogram in May 2001

1.1.8

Gaharu Grade

Price per Kilogram (USD)

341

237

172

111

Uses of Gaharu

Gaharu has three principal uses which have a wide use in medicine (general pain reducer, dental pain, kidney and rheumatism medicine), as venom repellent, in perfume and incense raw material. Wood without or with low content of resin can be used for boxes, interior or veneer. The inner fibrous bark has occasionally been used locally as raw material for clothing and ropes. Gaharu contains more than 12 chemical components that can be extracted.

1.1.9

Overview of Malaysia Gaharu

Five species of Gaharu are recorded for Peninsular Malaysia and all are believed to be able to produce oleoresins. There is very little information on the quality of the different Gaharu produced. The most popular species generally associated with Gaharu 8

is A.malaccesis. This species is synonymous with A.agallocha from India (Hou 1960). In the market, Gaharu is the trade name generally refers to the resinous wood from any of the Aquilaria species despite the difference in or absence of local names. It is very difficult to identify the species from the resinous wood alone.

Table 1.3: Gaharu Producing Species of Aquilaria in Peninsular Malaysia

SPECIES

LOCAL NAME FOR

GRADE

RESINOUS WOOD A.malaccesis

Gaharu

Medium

A.microcarpa

Garu

A.hirta

Chandan

Medium

A.rostrata

A.beccariana

Gaharu , Tanduk

Aquilaria malaccensis is distributed throughout Malaysia, except in the states of Perlis and Kedah (Whitmore 1972), and is known to produce medium quality grade Gaharu

(Burkill 1966). There are also unconfirmed reports of A. malacensis in

Bangladesh, although recent reports indicate that this species no longer exists in the wild (Khan 1993 cited in Chakrabarty et al., 1994). In India A.malacensis, formerly known as A .agallocha, is native to Arunachal Pradesh, Assam, West Bengal, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim, and Tripura (Chakrabarty et al., 1994). In natural habitats, this species can be found growing at an elevation of 1000 m, but is localized mainly in the foothills and undulating slopes of evergreen and semi evergreen forests.

Gaharu is one of the most expensive and highly prized commodities (Barden et al., 2000). Several raw forms are traded. They range from large sections of trunk to 9

chips, flakes, oil and even the spent powder wastes after oil extraction. Large pieces of Gaharu are hard to come by nowadays. In Malaysia, chips, flakes, oil and powder waste after extraction are the most common forms traded. Depending on the grade and quality, prices could range from 60 sen per kg for the low and mixed grades to more than RM 2000 per kg for the high grade.

The Gaharu wood is hard and light with rough texture, white or brownish yellow. It has a highly appreciated and priced fragrant wood caused by accumulation of scented resin. Production of Gaharu may be influenced both by genetic and environmental factors but the general understanding is that the fragrant oleoresin that permeates the heartwood of some trees is produced as a response to wounding and/or fungal infection. They have a wide use in medicine (general pain reducer, dental pain, kidney and rheumatism medicine), as venom repellent, in perfume and as incense raw material. Wood without or with low content of resin can be used for boxes, interior or veneer. The inner fibrous bark has occasionally been used locally as raw material for clothing and ropes. Gaharu contains more than 12 chemical components that can be extracted.

Since Gaharu

is valuable, local entrepreneur has adopted hydrodistillation

technique that much practice traditionally especially in rural areas of Cambodia and India. But now, local entrepreneur more prefer effective technique that produce higher yield of oil using other extraction techniques.

Figure 1.2: Gaharu Chip

Historical record showed that Gaharu

was harvested and traded in

PeninsularMalaysia before 684 CE. The harvesting of tree species for Gaharu persists until today. Tree species containing Gaharu are found in the natural forests. Species in the family Thymelaeaceae in Malaysia reported to produce Gaharu are shown in Table below.

Table 1.4: Gaharu producing species in the family Thymelaeaceae

Resin content of Gaharu is often tested by igniting the wood and smelling the smoke, while watching for bubbling of resin as the wood burns. When there is a large amount of Gaharu to be graded, buyers often make the first sort by using the water test, separating pieces that float (because of lower resin content) from those that sink (high resin content, better quality). After they are dried again, pieces are graded based on colour and size. Mixed chips of good quality (black, black and brown) are graded as C and often fetch a higher price per gram than large pieces of A and B grade.

According to Information collected from individual involved in the trade, prices in May 2001 and May 2002 averaged as follows:

Table 1.5: Gaharu Grade

1.1.10 Overview of Essential Oil

Essential oils are the volatile, aromatic oils obtained by steam or hydrodistillation of botanicals. Most essential oils are primarily composed of terpenes and their oxygenated derivatives. Different parts of the plants can be used to obtain essential oils, including the flowers, leaves, seeds, roots, stems, bark, wood, etc. Certain cold-pressed oils, such as the oils from various citrus peels, are also considered to be essential oils but these are not to be confused with cold-pressed fixed or carrier oils such as olive, grapeseed, coconut etc. which are non-volatile oils composed mainly of fatty 13

acid triglycerides. Other aromatic, plant-derived oils, which technically aren't essential oils because they are solvent extracted, include Absolutes (hexane followed by ethanol extraction), CO2's (liquid carbon dioxide used as the solvent) and Phytols or Florosols (fluoro-hydrocarbon solvent).

An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils,ethereal oils or aetherolea, or simply as the "oil of" the plant from which they were extracted, such as oil of clove. An oil is "essential" in the sense that it carries a distinctive scent, or essence, of the plant. Essential oils do not form a distinctive category for any medical, pharmacological, or culinary purpose. Essential oils are generally extracted by distillation.

Steam

include expression or solvent

distillation

extraction.

often

used. They

Other

processes

are

used

in perfumes, cosmetics, soaps and other products, for flavouring food and drink, and for adding scents to incense and household cleaning products.

1.1.11 Overview of Gaharu Essential Oil

Gaharu oil is made from the wood of Agar. There are different grades of Gaharu oil. Gaharu comes in solid or liquid form. Solids are only solid at room temperature, and if warmed slightly, it turns to mobile liquid. It is an anti-asthmatic and can be applied directly to the skin as it is non-irritating. The oil is very tenacious and only the tiniest of drops is needed to fill the air with its soul evoking aroma. It is a complex aroma with many nuances, deep and ethereal. The aroma takes about 12 hours to unfold and it will last on the skin for more than a day, and if placed on any material, the scent can last for 14

months. It can be used as a perfume, an aroma therapy and an essential oil or as an aid for the deepest meditation. This fragrance will unlock the subconscious and allow you to go deep into your memories.

Distilled “Gaharu ” essential oil can command up to RM 100,000 per kilogram and the price is expected to rise due to increasing international demand. The odour of Gaharu is complex and pleasing, with few or no similar natural analogues. As a result, Gaharu and its essential oil gained great cultural and religious significance in ancient civilizations around the world.

1.2

Product Market Survey

1.2.1

Survey on Estimate Cost of Cultivation Gaharu

Referring to Forest Research Institute Malaysia (FRIM) deputy director-general Dato Dr Abdul Rashid Abdul Malik, Malaysia has about 1,000 hectares of Gaharu plantation with 30 hectares reaching maturity after seven years. The producing countries could only meet 35 per cent of the demand and Malaysia comes in third place with only six per cent. India is the main producer, contributing only 12 per cent with Indonesia in second place, contributing seven per cent. Thailand, Laos and Cambodia come after Malaysia. 80 countries use Gaharu with the Middle East the biggest importer, getting 25 per cent of Gaharu resins and its essential oil - known as the „Oud‟ oil. Currently, annual Gaharu exports from Malaysia amounts to RM 72 million a year. 15

One tree can produce about 1.5 kilogrammes of Gaharu on average but then again, this all depends on the size and age of the tree and the inoculation given. An acre of land could accommodate 800 trees and on average it could take RM15 000 to RM20 000 to nurture an acre of plantation, adding that most of cost goes to getting the seedlings which could cost from RM 8 to RM 10 each. A kilogram of unprocessed Gaharu heartwood can fetch as much as RM 10,000 per kilogram. The estimated value for one kilogram of Gaharu karas is between RM5, 000 to RM60 000 while a liter of oil is estimated to be worth 10 times more than wood. Low grade of resinous wood is used for oil production normally require minimum 20 kg to produce 12 ml of oil. Distilled Gaharu essential oil can command up to RM 100 000 per kilogram and the price is expected to rise due to increasing international demand. The cheapest Oud oil is distilled from Gaharu that costs as little as $20 a kilogram, while the finest Oud can be distilled from Gaharu that costs as much as $7 000 per kilogram (2008).

Additional information:

1 acres = 800 trees 1 tree = 1.5 kg of Gaharu 20 kg of Gaharu = 12 ml of oil 13 trees = 12 ml of oil

1.2.2

Survey of Gaharu Distribution

Gaharu is widely distributed in south and south-east Asia. There are differing accounts of the countries in which it occurs. According to Oldfield et al. (1998), A. Gaharu is found in 10 countries which are Bangladesh, Bhutan, India, Indonesia, Iran, 16

Malaysia, Myanmar, Philippines, Singapore and Thailand. Three species of Aquilaria are found in Malaysia: A. hirta, A. malaccensis and A. rostrata. Aquilaria malaccensis is well distributed throughout Peninsular Malaysia, except for the States of Kedah and Perlis ( Barden et al., 2000), but although the species has good geographical coverage, its occurrence in rather rare, with trees often locally scattered.

1.2.3

Local market

Gaharu has been recognized by the local Malaysian since a long time and its valuable oil has been collected and extracted traditionally as a â&#x20AC;&#x17E;backyard industryâ&#x20AC;&#x; by the local people in Kelantan. The process of extracting the oil takes until 96 hours of distillation process. High quality Gaharu can reach up to RM10 000 per kg depending to the grade of the resin and is burned like an incense stick. A 12 g bottle of oil is sold at between RM50 and RM200. A 21 extraction pot factory will use up to a tonne of wood per month. This shows how intense Gaharu usage for one factory alone.

According to TRAFFIC, in 2000, it is estimated that nearly 700 tonnes of Gaharu were produced in the international market mostly came from the jungle of Malaysia and Indonesia. The price is estimated at least RM3.5 billion. Gaharu has been Malaysia natural treasure because of its rarity and its high value (M. Haikal, 2006). As it is a rare species, hard to found, and because of its high value, the federal Forestry Department has urged the state governments to regulate the collection, trade and processing of Gaharu through a licensing system where the Gaharu collectors or buyers have to pay a royalty fee amounting to 10% of the raw material market price and an extraction permit is issued and this will facilitate the traders in obtaining export and CITES (Convention on International Trade in Endangered Species) permit (Hillary Chiew, 2005). 17

Figure 1.3: Plantation of Gaharu in Malaysia

Gaharu Technologies SdnBhd (Plantation), Gopeng, Perak

Gaharu Technologies SdnBhd, Ipoh, Perak

Very little local consumption of Gaharu chips or oil for incense or perfumery was recorded in Malaysian during the survey period. The price of one kilogramme of top-grade Gaharu on sale had risen from MYR3000 (USD790) in 1996 to MYR15 000 (USD3900) in 2006, with some traders quoting retail prices of above MYR20 000/kg verbally for „limited stocks‟ of their highest grade. These prices are among the highest prices ever recorded for Malaysia (see Figure 1.3). However, as has been noted, analysis of pricing is hampered by a lack of a standard grading system.

Although most Gaharu chips and oil are believed to be exported, there appeared to be a considerable domestic market in Malaysia for Gaharu incense and medicine, particularly among the ethnic Chinese. Incense had been reported as being the “primary” 18

use of Gaharu in Malaysia (Barden et al., 2000). Current research findings supported this, with manufactured Gaharu incense on sale in Malaysian-Chinese prayer-article shops including many product ranges of sticks, cones, coils (both raised coils and flat coils) and powder. These items were sold at a premium, with Gaharu joss sticks roughly five times the price of normal joss sticks (MYR20 (USD5.2) per packet, compared with MYR4 (USD1) per packet).

There was no evidence of Gaharu use among the community of ethnic Indians in Malaysia. A survey of five shops selling incense and oil at the Batu Caves Hindu Temple Complex, Selangor, (November 2005) revealed a wide variety of “agarbatti” incense sticks manufactured both locally and in India, however none of these products claimed to contain Gaharu. LaFrankie (1994) observed that „Aquilariaagallocha‟ was sold in Indian spice shops throughout Malaysia for a MYR2.50 per 100 gm (USD10 per kg) – however this finding could not be confirmed in the 2005-6 survey period.

Figure 1.4: Trends in the price of top grade Gaharu wood chips on sale in Malaysia (1880-2000) 19

1.2.4

Global Market Demand

The consumer market for Gaharu is well developed in the Middle East and Northeast Asia where Gaharu has been used for over one thousand years. Taiwan, Singapore, Hong Kong and Bangkok are major traders of Gaharu while Thailand, Indonesia, Vietnam and Malaysia are major producers. The increasing scarcity of illegal forest Gaharu makes plantation grown Gaharu much sought after to meet global demand.

During market research conducted in the UAE, products from a wider range of range States were claimed as countries-of-origin at the point of sale. The table below shows the number of shops (out of a total number of 31 shops visited in 2005 and 10 shops in 2007) where Gaharu products were sold claiming to be from the following range States:

Among the traders and vendors interviewed, a common conclusion was that while Malaysia and Indonesia were the bulk supply countries, â&#x20AC;&#x17E;Cambodianâ&#x20AC;&#x; Gaharu was 20

one of the most popular in the market. It is likely that many of these attributed countriesof-origin function as „brand names‟ for Gaharu of particular aroma, appearance and price structure – rather than reflecting accurately the actual country of origin.

1.2.5

Asian and Middle East Market

1.2.5.1 Taiwan Market Demand

Taiwan has long been a major trader in Gaharu for both medicinal and cultural uses. According to official records, 6,843 tonnes of unprocessed Gaharu was imported to Taiwan in the ten years to 2003. Prices of Gaharu for medicinal use vary between US$ 3,000 to US$ 30,000 per kilogram and processed oil between US$ 7,000 to US$ 61,000 a litre. Large high quality pieces suitable for ornamental sculptures can sell for up to US$ 100,000 per kilogram.

1.2.5.2 Japan Market Demand

In Osaka, Japan, a shop known as Jinkoh-ya (literally, “Gaharu Store”) has been trading Gaharu products for over 350 years. During the period 1991-1998, according to official Customs figures, 277,396 kilograms of unprocessed Gaharu was imported into Japan, or an average of over 34 tonnes a year. A 2004 price survey of unprocessed

Gaharu pieces found prices ranging from US$ 320 to US$ 22,700 per kilogram with the highest grades selling for between US$ 9,000 to US$ 272,000 per kilogram.

1.2.5.3 Middle East Market Demand

Demand for Gaharu products in the Middle East significantly exceeds Eastern Asia. One well known Saudi Arabian retailer specializing in oud (agar oil) has over 550 retail outlets across 17 countries with over 600,000 customers and is one of the worldâ&#x20AC;&#x;s largest perfume retailers in a market worth US$ 3.3 billion a year. The company imports 45 tonnes of unprocessed Gaharu yearly to produce 400 different fragrances with oud as the basic ingredient and has a production capacity of 30 million bottles of perfume a year.

1.2.6

Survey on Price Trends

The Gaharu trade is driven primarily by economic factors that have a dramatic effect on patterns of consumption and collection. Comparison of prices and identifying trends is frustrated by the absence of a standard grading system. However, it is possible to make broad assessments of the prices of â&#x20AC;&#x153;top gradeâ&#x20AC;?, the average prices and the range of prices from year to year. It is clear that prices of Gaharu have fluctuated rather dramatically in response to global economic factors.

The Gaharu market in Malaysia has experienced a number of booms and crashes over the years. In 1880, top grade Gaharu was sold for up to four Straits Dollars (substantively equivalent to MYR4 or USD1) per kg. By 1907, prices doubled to MYR8.20, eased to MYR6.50 in 192036 and then crashed to MYR1.30 in 1925 due largely to competition from the Netherlands Indies (which is now Indonesia). Pahang was reported to be very badly hit and was unable to arrest the general downturn in revenues accrued from the trade in Gaharu and other forest produce (Bland, 1886; Foxworthy, 1922; Kathirithamby-Wells, 2005). No account has been made of general inflation, but prices of Gaharu had risen to MYR83 per kg by 1950 (Chiew, 2005).

In the 1970s â&#x20AC;&#x153;best qualityâ&#x20AC;? reached around MYR170 in the Baram, Sarawak (Chin, 1985; Hansen, 1988). In early 1980 the same quality reached MYR413 in the Baram and MYR1300 for similar quality ex-village in Peninsula Malaysia (Chin, 1985; Gianno, 1986). Prices then rose sharply into the 1990s, reaching MYR2000 by 1995 (Anon., 1995); MYR3000 by 1996 (Albela, 1996) and MYR4000 by 1999. The first half of the 2000s have seen the upward trend continue with prices per kg increasing to MYR5000 by 2003 (Lim et al., 2003); MYR8000 by 2004 (Chiew, 2004); and as high as MYR10 000 by 2005 (Chiew, 2005).

1.2.7 Gaharu Trade

1.2.7.1 Forms of Gaharu in Trade

Gaharu is one of the most expensive and highly prized commodities (Barden et al., 2000). Several raw forms are traded. They range from large sections of trunk to to 23

finished products such as incense and perfumes. Branch or trunk sections are the largest forms in trade and may be one to two metres in length and weigh more than 10-20 kg. Segments and smaller pieces of Gaharu , ranging in size from branch or trunk sections to chips or flakes, are the most sought after by consumers from the Middle East. Gaharu chips and flakes are the most common forms of Gaharu in trade. Only 10-20% of a large slab or piece of Gaharu can be drawn into chips and flakes, with the remainder sold as powder/dust or used for oil distillation. Most forms of semi-processed or raw Gaharu in trade only reach about 10 cm in length and can be accurately referred to as chips, fragments, shavings and splinters, even breaking down to tiny particles of powder and dust.

Flakes include shavings or pieces that have broken off during harvesting and transport, as well as small pieces produced deliberately. Gaharu powder is normally a fine powder of even particle size and should not be confused with the much cheaper waste powder, which is a by-product of oil distillation.. Gaharu oil is a highly valuable and frequently traded product. Oil is produced by steam distillation of generally lowgrade Gaharu chips and powder. Although distillation is a cost-effective method of using secondary Gaharu products, oil yields are generally very low and the extraction process is reported to be very tedious and time consuming.

Although synthetic Gaharu

compounds are used to produce poor-quality

fragrances and incense sticks, there are currently no synthetic substitutes for high-grade incense or oil. Synthetic Gaharu oil sells for less than USD100/kg (Heuveling van Beek and Phillips, 1999).

1.3

Project Feasibility and Site Study 24

Being in the right location is a key ingredient in a businessâ&#x20AC;&#x;s success. If a company selects the wrong location, it may have adequate access to customers, workers, transportation, materials, and so on. Consequently, location often plays a significant role in a companyâ&#x20AC;&#x;s profit and overall success. A location strategy is a plan for obtaining the optimal location for the company by identifying company needs and objectives, and searching for locations with offerings that are compatible with these needs and objectives. Generally, this means the firm will attempt to maximize opportunity while minimizing costs and risks.

1.3.1

Malaysian Economic Situation

Malaysia has gained a wide reputation as a cost competitive location for the manufacture of high technology products for regional and world markets although has a stiff competition from China, the new rising economic country from East Asia. The Malaysian formula of success for attracting investments especially foreign direct investment (FDI) into the manufacturing sector are attributed to an educated, professional and productive workforce with excellent infrastructure, combined with a government that is committed to maintain a business environment conducive for growth and profits.

Strategically located within the hub of South-East Asia, Malaysia is positioning itself as a springboard into the growing ASEAN market. Malacca Strait as the main route of import and export via shipping from the west to the east give us a lot of advantages in term of economic value. Many investors are keen to walking up to the vast potential of the markets in Asia, especially that of the ASEAN countries which have a combined population of almost half a billion. In future, ASEAN will be even a more 25

attractive market with the establishment of the ASEAN Free Trade Area (AFTA) when intra-regional tariffs will be reduced to between 0% and 5%. Manufacturers who have production bases within the region will be able to export freely or with minimal import duties to other ASEAN member countries.

The Malaysian government itself has been so far more than supporting the manufacturing sector especially with the draft of Malaysiaâ&#x20AC;&#x;s Second Industrial Master Plan (IMP2), 1996-2005, which focuses on the further development of the manufacturing sector. This consists of R&D back-up, the development of supporting industries, packaging, distribution and marketing. The integration of manufacturing and other operations aims to strengthen industrial linkages and increase productivity and competitiveness of industries in Malaysia.

1.3.2

Criteria of Plant Site Selection

Each industry has particular needs that cause a specific site to be more appropriate for their uses than another. However, community officials and leaders can discover some basic standards that will enhance the probability that an industrial site is ready for the construction of a manufacturing facility.

Location of plant partially determines operating and capital costs. Location fixes some of the physical factors of the overall plant design, for example heating and ventilation requirements, storage capacity for raw material taking into consideration

their local availability; transportation needs, power and labor needs, and also taxes. Government plays an important role in the choice of the location.

The following criteria provide general guidelines to assist community officials and leaders in evaluating the ability of their community to seek some basic foundations required for the creation of an industrial site factors considered while selecting a plant site are:

Transportation

The transport of materials and products to and from the plant will be an overriding consideration in site selection. If possible, a site should be selected that is close to at least two major forms of road, rail, waterway (canal or river), or a sea port. The least expensive method of shipping is usually by water, the most expensive is by truck. Sometimes, there is usually need for convenient air and rail transportation facilities. A location which has several competing railroads, ports and road networks as well as waterways in order that the competition will help to maintain low rates and give better service should be chosen.

Reasonable land price

The land will influence the working capital. In terms of reasonable, it means that with the good incentive from local government and low land price. The lowest land price will become useless if the set up location of plant is not strategic enough and the land 27

characteristic does not fulfill the best condition. Moreover, if the land chosen is not classified as industrial area, the condition should be change first. State and local tax as property income, unemployment insurance and similar income vary one location to another.

Distance from Market

Demand versus distance, inventory storage requirements, growth or decline, completion-present and future. The location of market or intermediate distribution centers affects the cost of product distribution and the time required for shipping. The buyer usually finds that it is more advantage to purchase from nearby sources. Market of major final product and by-product should be considered.

Waste and effluent disposal facilities (Safety and environmental impacts)

All industrial plants especially chemical plants will produce waste products. The site selected should have satisfactory and efficient disposal system for plant wastes or effluents such as the drainage systems and dumping sites. Each individual plant has to treat their waste disposal according to standard and procedure of Department of Environment (DOE). Water discharge has to be treated before channeled to open drains. Each plant also has to obtain approval for site suitability from DOE before commencement of operation. Therefore it is important to choose a location that will secure a smooth operation for the plant and gives low impact on the environment.

Raw materials or semi-finished products

These particularly important if large volumes of raw material are consumed because these permit considerable reduction in transportation and storage charge. Any way attention should be given to the purchased price of the raw materials, distance from the source of supply, purity of the raw materials, reserve stock and storage requirements. In order to save the transportation costs, the plant should be located near to the raw material supply and sources.

Energy Supply

Power and steam requirement is high in most industrial plants and fuel is ordinarily to supply this utilities. Location should near to the hydroelectric installation if the plant using electrolytic process. If the plant requires large quantities of oil or coal, location near a source of supply may be essential for economic operation. The local cost of power can help determine whether power should be purchased or self-generated. Local authorities or whoever provided power supply to locations should have a contingency plan if power failure occurs during plant operations beside contingency plan from the plant itself.

Prospective Market for Products

Consumer products often are delivered in small shipment to a large number of customers. In an international market, there may be an advantage to be gained by locating the plant within an area with preferential tariff agreements. Since agarwood acts as a raw material for the production of consumer goods like soap, essential oil, and joss, it is always advantages for the plant to be situated in industrial area.

Water Source â&#x20AC;&#x201C; Quality and Quantity

Water is needed by every processing plant for the number of different purposes. Usually, water is needed for cooling the water, cleaning the equipment, heating and other functions. Potable water is needed for drinking and food preparation. The plant site must have an adequate amount of each type of water at all times of the year. Not only the amount and quality but the temperature of the water is important. The size of the heat exchanger is inversely proportional to the temperature difference between the cooling water and the material being cooled. Due to the reasons, we must make sure that the plant locations that have been chosen are adequate in water resources.

Amount of Site Preparation Necessary (site condition)

The sub soil should be sufficient land to meet the present as well as the future space requirements of the plant equipment. Also an ideal chemical plant site is above the flood plain, flat, has good drainage, a high soil bearing capability, and consists of sufficient land for the purposed plant and for future expansion.

Operating labor

Labor will be needed for construction of the plant and its operation. Skilled construction workers will usually be through it from outside the site area, but there should be an adequate pool of unskilled labor available locally, and labor suitable for training to operate the plant. Some of the factors that should be considered on labor are supply, kinds, nationality, diversity, intelligence, wage scales, efficiency and costs.

Political and Strategic Considerations

Capital grants, tax concession and other inducements are often given by governments to direct new investment to preferred locations, such as areas of high unemployment.

Government Incentives

In order to attract new investors, the government will offer an incentive to them, the better the incentive offered the feasibility to build the plant there would be better.

Local Community Considerations

The proposed plant must fit in with and be acceptable to the local community. The surroundings should be good and peaceful. On a new site, the local community must be able to provide adequate facilities for the plant personnel, schools, banks, housing and recreational and cultural facilities.

Corrosion

Once the general area for the plant has been determined, the effect of neighboring industries should be considered when picking the specific site. Their presence may indicate an increased corrosion rate.

Other Factors

Three factors are usually considered the most important. These are the location of the markets and raw materials and the types of transportation to be used.

1.3.3

Overview of Several Strategic Sites in Malaysia

Even though there is a long history of harvesting Gaharu in Malaysia, its use and trading has been limited. It was only until the 1980s, when there was an increase in international demand for Gaharu that more harvesting activities took place in various parts of the country. Currently, the five states known to produce Gaharu are Kedah, Perak, Kelantan, Terengganu and Pahang (Table 1.6).

Table 1.6: Main Gaharu producing areas and number of harvesters in Peninsular Malaysia

1.3.4

Site Study

Location for the plant plays very important role because it can effect on the plant operation and its success. For the construction of our plant, we have listed three main industrial sites that located at east and south of Peninsular Malaysia. Since the plant is using Gaharu as raw material, it is ought to be construct near the related sites as a supplier. In Malaysia, most of the raw material is located in Perak, Johor and Selangor, whereas these sites can be found in :

a) Kundang, Rawang , Selangor. b) Batang Padang Bidor Perak c) CountyJementah,Segamat, Johor 33

Location and

Kundang, Rawang,

Characteristics

Selangor

Developer

Perbadanan

Batang Padang Bidor Perak

Kemajuan Perbadanan

Negeri Selangor (PKNS)

Kemajuan

Negeri

Perak (PKNP)

CountyJementah,Segamat, Johor ď&#x201A;ˇ

Johor

State

Development

Economic Corporation

(JCORP)

Distance from the

nearest town -

14 km from Bandar

12.5km from Tapah

6 km from Segamat

Rawang

71km from Ipoh

211km from Johor Bahru

48.8 from Gopeng

37km from Slim River

Tenaga Nasional Berhad

Pasir Gudang power station

Sultan

from

Petaling Jaya -

25km from Kepong

30km

from

Damansara Power supply

Tenaga Nasional Berhad

Iskandar

Power

Station Water supply

Syarikat Air Selangor Sdn Syarikat Air Perak Sdn Bhd

Tanjung Bin Power Station

Syarikat Air Johor Berhad (SAJ)

Bhd

Area available (acre) 24

Land prices (RM/ft2) 12

industry Medium

preferred

industry

Port facilities

Klang Port

Type

and

heavy Medium and heavy industry

Medium

Lumut Maritime Terminal Sdn Segamat Inland Port (SIP) Bhd (LMT)

Land transportation



PLUS Highway



Utara Selatan Highway



Tun Razak Highway



Batu Arang



Tapah road



Main



Lebuhraya Guthrie



Jalan Gopeng

Corridor

Lebuhraya

Material



Supplier

Gaharu



Jalan Muar-Labis



Jalan Batu Enam



Jalan Bekok



Jalan Tasik Alai

Compugates Marketing Sdn



Agarwood Synergy Industries

Bhd



Rnz Agarwood

Gaharu Technologies Sdn.



Malacensis

KL-

R esources Bhd 

Compugates

Em as



S dn 

Segamat Jalan Pagoh

Kuala Selangor

Raw

Muar-Ledang-



Shah

Alam 

road

Bhd

Plantation

Malaysia

Marketing Sdn Bhd 



Nurseri Tetap Harum



Senai Airport

Malayagar Enterprise



Kelnet Biotech



Vintage

Growth

Sdn Bhd Airport Facilities



S ul t an Az i z

Abdul



Sultan Azlan Shah Airport

S hah

Ai rport .

Table 1.7: Comparison of short-listed of the potential site location

1.3.5

Decision Site

After considering the available site locations that depend upon several factors including primary and specific factors, Kundang, Rawang Selangor is chosen as the site for this proposed Gaharu plant selected as a totally satisfactory solution for future benefits. Generally the main reasons why Kundang, Rawang Selangor have been chosen as the Gaharu industrial area are:

Kundang, Rawang Selangor had been specialized for heavy and medium industries where waste treatment is easy to carry out.

ii)

Close to raw material sources. We can get our raw materials from Gaharu

Em as R esources S dn Bhd , Compugates Marketing Sdn

Bhd, Malayagar Enterprise, Kelnet Biotech and Vintage Growth Sdn Bhd. So, the price of raw materials is cheaper. iii)

Reasonable land price (RM 12.00 per square feet) compared to the other sites. Since our plant is quite small, the land price wonâ&#x20AC;&#x;t affect the economic analysis much.

iv)

Since the industrial is new, so there is much space for us to construct our plan and for our future expansion. The available area is 24 acres (9.71246hectares).

This location is quite near to Klang Port, so that any trade involving import and export product to the other countries can be accomplished easily.

vi)

Good transportation in terms of road facilities, railway, airport and seaport to get raw materials and market our product.

vii)

Attractive incentives from Selangor State Government. The state government is giving Pioneer Status, Investment Tax Allowance (ITA), Infrastructure Allowance, Incentives for Strategic Projects, Exemption on Import Duties, and Discount on Electricity Bills etc.

viii)

Adequate supply of electricity and water. Tenaga Nasional Berhad to supply electricity. On the other hand, Syarikat Air Selangor Sdn Bhd can supply water.

1.3.6

Proposed Plant Layout

Figure 1.5: Site Layout for Production of Gaharu Essential Oil

SECURITY PARKING LOT

PARKING LOT

PRAYER ROOM PLANT MANAGEMENT

CANTEEN

OFFICE

SECURITY DEPARTMENT

STORE

MAINTENANCE WORKSHOP

R&D DEPARTMENT WORKSHOP 3 LAB

Plant Utilities Parking Lot Control Room

Agarwood Waste

Raw Material Warehouse (Gaharu)

RESERVED LOT (FOR FUTURE EXPANSION) 38

1.4

Review of Physical and Chemical Properties Data

1.4.1

Physical Properties of Essential Oil

The first and foremost physical properties of essential oil are the highly fragrant, concentrated, and potent substances. Essential oil has a liquid-soluble molecular structure which allows them to pass easily through the skin. They penetrate into the fat layers of the skin quickly, which is why massage is such an effective treatment. Other than that, it is volatile, so that it is easily evaporate into air. The storage of essential oils is usually in a dark bottle because of it is sensitive to light. Essential oils are not standard product and will vary from batch to batch. Chemical variations will occur based on the time of day, harvest time, growing location and part of the plant to be extracted. They are cytophylactic which regenerate new cells and enhance the function of our organs.

1.4.2

Physical properties of component in Gaharu essential oil

Based on a study, Gaharu have been reported to contain sesquiterpenoids of eremophilane, spirovetivane, eudesmane, non-guaiane, guaiane and prezizaanetype, 2-(2-phenylethyl)chromone derivatives and many more (Jun-ya Ueda et al. 2006). The first investigation on Gaharu was done by Kafuku and Ichikawa (Shimada et al. 1982). Aroma from Gaharu is produced by sesquiterpene alcohol. Chang et al., (2002) reported that several chemical compounds such as agarospirol, guaiene, jinkohol and jinkohol II have been detected in Malaysian Gaharu oil. Some of the 39

more important compounds are agarospirol, jinkohol-eremol, jinkohol and kusenol that may contribute to the characteristic aroma of Gaharu (Nakanishi et al., 1984, Ishihara et al., 1993). Other compounds such as 2-(2-4‟-methoxyphenylethyl) chromone produce a long lasting fragrance upon burning.

Research conducted by Nakanishi succeeded in characterizing jinkohol (2βhydroxy-(+)-prezizane) in Gaharu

originated from Indonesia, through benzene

extraction. This team also found two new sesquiterpene compounds in AquilariamalaccensisLamk. from Indonesia, comprising jincoheremoldanjincohol II, called as type B to differentiate it from the type A of A. agallochaRoxb., and isolated alpha-agarofuran and (-)-10-epi-gamma-eudesmol, oxo-agarospirol as the main constituent at Gaharu type B (Burfield 2005b). In Burfield (2005b), it was stated that Yoneda managed to identify the main sesquiterpene that existed in Gaharu type A (in A. agallocha) and type B (in A. malaccensis). Gaharu type A contained βagarofuran 0,6%, nor-ketoagarofuran 0,6%, agarospirol 4,7%, jinkoh-eremol 4,0%, kusunol 2,9%, dihydrokaranone 2,4%, and oxo-agarospirol 5,8%. Meanwhile, in Gaharu type B were identified compounds comprising α-agarofuran(-)-10-epi-γeudesmol 6,2%, agarospirol7,2%, jinkohol 5,2%, jinko-eremol 3,7%, kusunol 3,4%, jinkohol II 5,6% danoxo-agarospirol 3,1%.

β-agarofuran Formula

C14H22O

Physical state

Flash Point

113.281 °C

Boiling Point

269.305 °C at 760 mmHg

Molecular Weight

206.323898g/mol

Density

1.008 g/cm3

Enthalpy of Vaporization

48.699 kJ/mol

Nor-ketoagarofuran Formula

C14H22O2

Physical state

Flash Point

127.781 °C

Boiling Point

313.614 °C at 760 mmHg

Molecular Weight

222.32328 g/mol

Density

1.066 g/cm3

Enthalpy of Vaporization

55.471 kJ/mol

Agarospirol Formula

C15H26O

Physical state

Flash Point

114.6°C

Boiling Point

311.00 to 312.00 °C at 760mmHg

Molecular Weight

222.3663 g/mol

Density

0.96 g/cm3

Enthalpy of Vaporization

64.139 kJ/mol

Kusunol Formula

C15H26O

Physical state

Flash Point

236.00 °F

Boiling Point

309.00 to 310.00 °C at 760mmHg

Molecular Weight

222.366 g/mol

Density

0.958 g/cm3

Enthalpy of Vaporization

64.574 kJ/mol

Jinkoh-eremol Formula

C15H26O

Physical state

Flash Point

113.1°C

Boiling Point

309.6°C at 760mmHg

Molecular Weight

222.36634 g/mol

Density

0.96g/cm3

Enthalpy of Vaporization

63.072 kJ/mol

1.4.3

Chemical Properties of Essential Oil

Most people either use essential oils for their therapeutic effect or for the fragrance alone but it is also interesting to take note of the chemistry, of which the oils are made up from. Essential oils, like all organic compounds, are made up of hydrocarbon molecules and can further be classified as terpenes, alcohols, esters, aldehydes, ketones and phenols etc.

The oil is composed by one or more terpenes and some oxygenated derivatives The oxygenated compounds usually have better organoleptic properties, so terpene separation is of interest. Nowadays preparation of essential oils with a high content on oxygenated terpenoids presents some difficulties, due to their delicate characteristics (Arce, Pobudkowska, Rodr´ıguez, &SotoEvery; 2007) Each single oil normally has more than a hundred components. When analyze essential oils with a chromatograph various organic components are found and the primary ones are as follows:

a) Terpene hydrocarbons b) Monoterpene hydrocarbons c) Sesquiterpenes d) Oxygenated compounds e) Phenols f) Alcohols g) Monoterpene alcohols h) Sesquiterpene alcohols i) Aldehydes j) Ketones k) Esters l) Lactones m) Coumarins n) Ethers o) Oxides

For terpenes hydrocarbons which are contains of monoterpene and sesquiterpenes. These monoterpene compounds are found in nearly all essential oils and have a structure of 10 carbon atoms and at least one double bond. The 10 carbon atoms are derived from two isoprene units. They react readily to air and heat sources. For this reason citrus oils do not last well, since they are high in monoterpene hydrocarbons and have a quick reaction to air, and are readily oxidized. Although some quarters may simply state that these components have anti-inflammatory, antiseptic, antiviral and antibacterial therapeutic properties while some can be analgesic or stimulating with a tonic effect, it could be seen as a very broad generalization, since this large group of chemicals vary greatly. Since some have a stimulating effect on the mucus membranes they are also often used as decongestants.

While, the other component is sesquiterpenes. These sesquiterpenes consist of 15 carbon atoms and have complex pharmacological actions and here we can look at

chamazulene, which is found in German chamomile. It has anti-inflammatory and anti-allergy properties. Another sesquiterpene often found in chamomile and rose, as well as other floral oils is farnesene. According to Professor Otto Wallach, terpenes was influenced the essential oil industry.

In addition, for oxygenated compounds, they are contains phenols and alcohols such as monoterpene and sesquiterpene alcohol. The phenols found in essential oils normally have a carbon side chain and here we can look at compounds such as thymol, eugenol and carvacrol. These components have great antiseptic, antibacterial and disinfectant qualities and also have greatly stimulating therapeutic properties.

Due to the nature of phenols, essential oils that are high in them should be used in low concentrations and for short periods of time, since they can lead to toxicity if used over long periods of time, as the liver will be required to work harder to excrete them. Phenols are also classified as skin and mucus membrane irritants and although they have great antiseptic qualities, like cinnamon and clove oil, they can cause severe skin reactions.

Monoterpene alcohol has good antiseptic, anti-viral and anti-fungal properties with very few side effects such as skin irritation or toxicity and has an uplifting energizing effect. Examples of these alcohols are linalool, citronellol and terpineol found respectively in lavender, rose and geranium, and in juniper and tea tree oil.

While sesquiterpene alcohol sesquiterpene alcohols are not commonly found in essential oils, but when found, like bisabolol in German chamomile, have great properties, which include liver and glandular stimulant, anti-allergen and antiinflammatory. Other oils that contain sesquiterpene alcohols are sandalwood (a-

santalol) as well as ginger, patchouli, vetiver, carrot seed, everlasting and valerian.

These aldehydes have anti-fungal, anti-inflammatory, disinfectant, sedative yet uplifting therapeutic qualities and are the component that imparts the citrus-like fragrance in melissa, lemongrass and citronella. These properties are best used in aromatherapy when the essential oil is used in low dilutions - around 1%. Should oils high in this component be used, it could cause skin irritation and sensitivity as for instance lemongrass oil. Aldehydes are also unstable and will easily oxidize in the presence of oxygen and even low heat.

Esters are formed from alcohols and acids, and are named after both their original molecules with the alcohols dropping the "ol" and gaining an "yl" and the acids dropping the "ic" and gaining an "ate". The esters found in essential oils are normally very fragrant and tend to be fruity and their therapeutic effects include being sedative and antispasmodic. Some esters also have anti-fungal and antimicrobial properties - like the anti-fungal properties in geranium oil. The most well known ester must be linalyl acetate, which is found in lavender, clary sage as well as petitgrain. These components are normally gentle in their actions and can be used with great ease.

Although ketones can be toxic, as in the case of thujone found in thuja and wormwood oil as well as pinocamphone found in others, they also have some great therapeutic benefits especially in the field of easing the secretion of mucus as well as cell and tissue regeneration. Other oils, such as hyssop, eucalyptus and rosemary have moderate amounts of ketones, and when used properly in aromatherapy can be greatly beneficial to the body. The ketone italidone found in everlasting, not only has the mucolytic (mucus easing) properties, but is also useful in skin regeneration, wound healing and reducing old scar tissue such as in wounds, stretch marks and adhesions. Essential oils high in ketones need to be used with care in pregnancy.

Lactones contain an ester group integrated into a carbon ring system and coumarins are also types of lactones. There are similarities between the actions of lactones, coumarins and ketones since they also have some neurotoxic effects and can cause skin sensitizing and irritation. Yet the sesquiterpene lactone, called helenalin found in arnica oil, seems to be responsible for the anti-inflammatory action of arnica oil. The amount of lactones and coumarins normally found in essential oils is very low, and does not pose a huge problem. Lactones also have great mucus moving and expectorant properties and for this reason elecampane is often used in the treatment of bronchitis and chest complaints. Some coumarins, like furocoumarin - bergaptene - found in bergamot oil are severely skin UV sensitive and should be used with great care should you be exposed to sunlight.

Phenolic ethers are the most widely found ethers in essential oils with anethol found in aniseed, the only real ether of importance together with methyl chavicol found in basil and tarragon. The main therapeutic effect of oxides are that of expectorant, with 1,8-cineole - commonly known as eucalyptol being the most well known.

1.4.4

Structure and Chemical Compound of Gaharu

Gaharu is a resinous wood and it is the resin that determines the quality of Gaharu . Many studies have revealed two major constituents of Gaharu , i.e. sesquiterpenes and chromones, as the main source of the fragrant.

About 50 years ago, the chemical content of fragrant Gaharu was isolated by Indian chemists from Aquilariaagallocha ROXB and they characterized several sesquiterpenes (Konishi et al., 2002). Twenty years later, Japanese scientists isolated and characterized many sesquiterpenes from two Gaharu types, the first, presumably originated from A. malaccensis and the second, “kanankoh” (in Japanese) (Konishi et al., 2002). Another constituent of Gaharu was also revealed, i.e. an oxygenated chromone derivative, followed by isolations of two new chromone derivatives in 1989 and 1990 by Chinese scientists.

Sapwood Gaharu exemplifies as merely unexuded resin, but rather it is deposited in the wood tissues of trees. This resin deposit renders the wood with loose fibers and white color becoming solidly compact, white in color, and fragrant in smell. This resin belongs to sesquiterpene group, which is easily volatile (Ishihara et al., 1991). Most of the compounds in Gaharu are identified as sesquiterpenoid group. One of the fragrant-smelling compounds in Gaharu

was first identified by

Bhattacharyya dan Jain as agarol, categorized as mono-hydroxycompunds (Prema and Bhattacharyya, 1962).

Research conducted by Nakanishi succeeded in characterizing jinkohol (2βhydroxy-(+)-prezizane) in Gaharu

originated from Indonesia, through benzene

Gaharu type B were identified compounds comprising Îą-agarofuran(-)-10-epi-Îłeudesmol 6,2%, agarospirol7,2%, jinkohol 5,2%, jinko-eremol 3,7%, kusunol 3,4%, jinkohol II 5,6% danoxo-agarospirol 3,1%.

Elucidation of structures of many kinds of 2-(2-phenylethyl) chromone and their derivative compounds have been thoroughly investigated by Japanese scientist and his group (Figure 9.) (Konishi et al., 2002).

Figure 1.6.Chemical structures of 6 2-(2-phenylethyl) chromones and an unkown 2-(2-phenylethyl)-chromone (1), flidersiachromone. Compound (1): 2-(2phenylethyl)-chromone, flidersiachromone; (2-7): 2-(2-phenylethyl)chromones, (2): 48

C19H18O5, (3): C1H14O4, (4): 6-hydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone, (5): dihydroxylderivative of 2-(2-phenylethyl)-chromone, (6): C1H14O3, and (7): C18H16O4 (Source: Konishi et al., 2002).

Yagura et al. (2005) isolated novel chromone derivatives from Gaharu , produced by intentionally wounding A. crassna and A. sinensis. The three compounds were characterized as diepoxytetrahydrochromones have not been reported from natural Gaharu product, i.e. Oxidoagarochromone with molecular formula of A (1) (C17H14O4); B(2): (C18H16O5); C(3): C18H16O6 .

Results regarding the analysis of GCMS (gas chromatography â&#x20AC;&#x201C; mass spectrometry) on 6-month old induced-Gaharu brought out 9 chemical constituents, of which only 4 constituents were identifiable that comprised 4-hydroxy-4-3thyl-2pentanone (5.3%), Oxirane, 2,3-epoxy butane (0.6%), 2-butoxy ethanol (70.5%) dan 1,2 benzene dicarboxylix acid (9%) (Figure 10) (Wiyono, 2008).

Figure 1.7. Chromatogram revealing constituents in 6-month old induced Gaharu 49

Further, results of GCMS analysis on the induced Gaharu

products

originated from Dramaga and Carita each comprising 2 sample trees revealed that there were 16 phenol compounds that belong to high group, and 8 phenols as low group (Table 1.8). Scrutinizing that Table 1.8, it seems that there has occurred a sequence (series) of secondary metabolite process, such as the evolving/release of iseugenol and veratrol compounds that function as perfumes and medicine, whereby those two compounds are not encountered in regular wood. The veratrol itself is evolved from phenol compounds that undergo hydrolysis into catechol, which further through a sequence of complex mechanisms, i.e. Kreb cycle, is transformed to veratrol. Likewise, eugenol compounds are evolved from guaiacol (main constituent of lignin) through ferulic acid intermediate.

Results of identification on Gaharu

resin indicated the presence of

caryophene compounds that typify the main constituents for eugenol which usually exists in clove leaves. In Gaharu resin were also identified cembren compounds (diterpenoid) that comprised a feromon compound effective for termites, a palustrol compound as antitusive, and copaene compounds that can function as essential oil and are rather toxic to be taken orally if the LD is 5000 mg/kg.

Recent study revealed distinct chemical compositions and its relative concentration of four Gaharu

woods from A. microcarpa that was artificially

induced by four Fusarium spp. from four different localities in Indonesia (Novriyanti et al., in press). Analysis using GCMS pyrolysis revealed that Fusarium sp. from TamiangLayang, Central Kalimantan had the highest confirmed constituent (12.89%), but Gaharu induced by Fusarium sp. from Molluca had the highest total concentration of odorant compounds (12.47%).

Further study done by the same group of scientists at FORDA of the Ministry of Forestry, Indonesia compared the chemical contents of Gaharu formed by natural process and by artificial induction (Santoso et al., unpublished data). The GCMS analysis showed differences in chemical contents of Gaharu harvested from these two processes (Figure 1.7).

Gaharu (Aquilariacrassna, Aquilariasinensis) is well known as incense in the oriental region such as Thailand, Taiwan, and Cambodia, and is used as digestive in tradisional medicine. Gaharu leaves are drunk as a health tea in Thailand and Taiwan. Charateristicsesquiterpenes and chromonederivates have been isolated from agarwood and some of these have sedative analgesic effects. Phytochemical research has been carried out on the trunk and resin of agarwood, but little is known about the pharmacological effects of agarwood leaves (Kakino et al., 2010).

Table 1.8. Phenol compounds present in the induced Gaharu products

Gaharu oil for use in aromatherapy has attracted more and more attention nowadays, especially for psychosomatic disease caused by stress. In the United Stated, aromatherapy is allowed for clinical use in syndromes, such as Attention Deficit Disorder and Attention Deficit Hyperactivity Disorder (Takemoto et al., 2008). During the aromatherapy, volatile compound is inhaled and it is important to know its pharmacological activity. The composition of volatile compounds in Gaharu oil varies. Takemoto et al. (2008) examined two types of Gaharu oil, i.e. from a Hong Kong market and originated in Vietnam, by SPME-GCMS to characterize their 52

volatile compounds. SPME-GC analysis revealed the composition in the gas phase, as follows: sample originated from Hong Kong market contained 47.1% benzylacetone, and sample of Vietnam made contained 61.5% a-gurjunene and 24.7% (+)-calarene as the main volatile components. GC analyses revealed volatile mass in a liquid extract, as follows: benzylacetone was accounted for only 0.96%, agurjunene for 15.1% and (+)-calarene for 17.3% of the whole oil (Figure 1.8). Spontaneous vapor administration system applied using 400Îźl of Gaharu oil showed that these two oil types gave similar sedative activity although the main component of each oil was different (Takemoto et al., 2008).

Figure 1.8. Structures of compound from Gaharu oil

When used as sedative, Gaharu

may affect central nervous system. A

sesquiterpene characterized as spirovetivane-type sesquiterpene, (4R,5R,7R)-1(10)spirovetiven -11-ol-2-one at a concentration of 100Îźg/ml, caused an induction effect on brain-derived neurotrophic factor mRNA expression in vitro neuronal cells of rat (Ueda et al., 2006).

Other part of Gaharu tree, leaves have been reported to have laxative effect. Oral administration of acetone leaf extracts of Aquilariasinenses gave a mild laxative effect in mice, but it did not cause diarrhea as a severe side effect and the main constituent that contributed to this effect was characterized as genkwanin 5-O-bprimeveroside (Figure 1.9) (Hara et al., 2008).

Figure 1.9: Major constituent genkwanin 5-O-b-primeveroside compound that caused mild laxative effect in mice (Source: Hara et al., 2008).

1.5

Process Screening for Extraction Methods of Gaharu Oil

1.5.1

Distillation 54

1.5.1.1 Introduction

Distillation is the most popular, widely used and cost-effective method for producing essential oils throughout the world. Distillation of aromatic plants simply implies vaporizing or liberating the oils from the plant cellular membranes in the presence of moisture, by applying high temperature and then cooling the vapor mixture to separate the oil from the water on the basis of the immiscibility and density of the essential oil with respect to water.

1.5.1.2 Principles of Distillation

The choice of a particular process for the extraction of essential oil is generally dictated by the following considerations:

a) Sensitivity of the essential oil to the action of heat and water b) Volatility of the essential oil c) Water solubility of the essential oil

Essential oils with high solubility in water and those that are susceptible to damage by heat cannot be steam distilled. Also, the oil must be steam volatile for steam distillation to be feasible. Most of the essential oils in commerce are steam volatile, reasonably stable to heat and practically insoluble in water; hence they are suitable for processing by steam distillation.

Essential oils are a mixture of various aroma chemicals, basically monoterpenes, sesquiterpenes and their oxygenated derivatives, having a boiling point ranging from 150˚ to 300˚C. When the plant material is subjected to heat in the presence of moisture from the steam, these oils are liberated from the plant.

For the oil to change from the liquid to the vaporphase, it must receive latent heat that, within the tank, can only come from condensing steam. Consequently, the temperature of the steam within the still must be higher than the temperature at which the oil boils in the presence of water on the surface of the plant material, otherwise there would not be a temperature gradient to take the latent heat from the condensing steam to vaporize the oil droplet. Thus, the energy from the steam in form of heat as latent heat of vaporization converts the oil into a vapor. But, as the boiling point of the oil is higher than that of water, the vaporization takes place with steam on the basis of their relative vapor pressures.

It is imperative to note that a liquid always boils at the temperature at which its vapor pressure equals the atmospheric or surrounding pressure. For any two immiscible liquids, the total vapor pressure of the mixture is always equal to the sum of their partial pressures. The composition of the mixture in the vapor phase (in this case, oil and water) is determined by the concentration of the individual components multiplied by their respective partial pressures.

For example, if a sample of an essential oil comprised of component A (boiling point, 190 ˚C) and water (boiling point, 100˚C) is boiled, after some time, once their vapors reach saturation, the temperature will immediately drop to 99.5˚C, which is the temperature at which the sum of the two vapor pressures equals760 mmHg. In other words, the oil forms an azeotropic mixture with water. Thus, any essential oil having high boiling point can be evaporated with steam in a ratio such that their combined vapor pressures equal the atmospheric pressure; the essential oil can be recovered from the plant by the wet distillation process.

1.5.1.3 Methods for Distillation

The following four techniques for the distillation of essential ils from aromatic plants are employed:

1. Water distillation (or hydrodistillation) 2. Water and steam distillation 3. Direct steam distillation 4. Distillation with cohobation

1.5.2

Extraction of Gaharu Essential Oil via Hydro distillation (Alternative 1)

1.5.2.1 Introduction

There are a few conventional and modern methods of extracting essential oils. It can be extracted by hydro-distillation, cold pressing, effleurage, hydro diffusion, supercritical fluid extraction, vapor-cracking, turbo-extractor and microwave extraction. In Malaysia, the techniques currently practiced in the industry for the extraction of essential oils are by hydro-distillation; steam, water and water / steam distillation and solvent extraction. The equipment required for carrying on distillation of plant materials depends upon the size of the operation and the type of distillation to be used. There are, however three main parts, which in varying size, form the base for all three types of hydro-distillation. The three universally employed parts are:

1. The retort or still proper 2. The condenser 3. The receiver for the condensate or oil separator

Ratio between quantity of condensed water and time may be designated as rate of distillation (kg/hr.). If the velocity of the rising steam is too low, the steam will stagnate in the condenser of the charge and complete exhaustion is impossible. Hence, if the velocity is too high, the steam may break through the charge, form steam channel, hurl plant particles into the condenser and partly clogging it. Hydrodistillation is commonly used for the extraction of essential oil. The essential oils of plants such as caraway, clove and sandalwood are examples of plants extracted by this process. When extracted they have an oil yield of 0.10 to 15.0 percent of essential oil.

1.5.2.2 Process and Structure

Hydro distillation is used in the manufacture and extraction process for obtaining essential oils.This is the simplest and usually the cheapest process of distillation. Hydro distillation seems to work best for powders and very tough materials like roots, wood, or nuts. The main advantages of this method are that less steam is used.

Figure 1.10: Hydro distillation process.

In distillation, the plant material is heated, either by placing it in water which is brought to the boil or by passing steam through it. The heat and steam cause the cell structure of the plant material to burst and break down, thus freeing the essential oils. The essential oil molecules and steam are carried along a pipe and channelled through a cooling tank, where they return to the liquid form and are collected in a vat. The emerging liquid is a mixture of oil and water, and since essential oils are not water soluble they can be easily separated from the water and siphoned off. Essential oils which are lighter than water will float on the surface.

In Hydro-distillation, the botanical materials are immersed in water and brought to a boil, Gaharu chips are fully submerged in water, producing a wood 'soup', and the still is brought to boil. The steam containing the aromatic plant molecules is captured and condensed and the oil floats to the top of the distilled water component. When the condensed material cools down, the oil and hydrosol are separated and the essential oil obtained. This method protects, the oil extracted to a 59

certain degree, since the surrounding water acts as a barrier to prevent it from overheating.

In this process, the material is completely immersed in water, which is boiled by applying heat by direct fire, steam jacket, closed steam jacket, closed steam coil or open steam coil. The main characteristic of this process is that there is direct contact between boiling water and plant material. When the still is heated by direct fire, adequate precautions are necessary to prevent the charge from overheating. When a steam jacket or closed steam coil is used, there is less danger of overheating; with open steam coils this danger is avoided. But with open steam, care must be taken to prevent accumulation of condensed water within the still. Therefore, the still should be well insulated. The plant material in the still must be agitated as the water boils, otherwise agglomerations of dense material will settle on the bottom and become thermally degraded.

Certain plant materials like cinnamon bark, which are rich in mucilage, must be powdered so that the charge can readily disperse in the water; as the temperature of the water increases, the mucilage will be leached from the ground cinnamon. This greatly increases the viscosity of the water-charge mixture, thereby allowing it to char. Consequently, before any field distillation is done, a small-scale water distillation in glassware should be performed to observe whether any changes take place during the distillation process. From this laboratory trial, the yield of oil from a known weight of the plant material can be determined. The laboratory apparatus recommended for trial distillations is the Clevenger system.

During water distillation, all parts of the plant charge must be kept in motion by boiling water; this is possible when the distillation material is charged loosely and 60

remains loose in the boiling water. For this reason only, water distillation possesses one distinct advantage, i.e. that it permits processing of finely powdered material or plant parts that, by contact with live steam, would otherwise form lumps through which the steam cannot penetrate. Other practical advantages of water distillation are that the stills are inexpensive, easy to construct and suitable for field operation. These are still widely used with portable equipment in many countries. The main disadvantage of water distillation is that complete extraction is not possible.

Hydro-distillation can be performed at a reduced pressure in a vacuum to lower the temperature to less than 100째C, which is useful in protecting plant material as well as the essential oil. Though hydro-distillation is the most common method for extracting and isolating the oils for perfumery, the high temperatures can also destroy the most delicate fragrance molecules, so hydro-distillation is preferred. However, it is a time consuming process and needs large amounts of plant material.

Besides, certain esters are partly hydrolyzed and sensitive substances like aldehydes tend to polymerize. Water distillation requires a greater number of stills, more space and more fuel. It demands considerable experience and familiarity with the method. The high-boiling and somewhat water-soluble oil constituents cannot be completely vaporized or they require large quantities of steam. Thus, the process becomes uneconomical. For these reasons, water distillation is used only in cases in which the plant material by its very nature cannot be processed by water and steam distillation or by direct steam distillation.

This method provides limited overheating protection since the surrounding water acts as a heat sink to reduce the maximum temperature. Great care is also taken in the processing to exactly control temperature and length of exposure to preclude damage to the oils' character. Hydro-distillation is used when the plant material has been dried and will not be damaged by boiling. It is also used for powdered materials 61

such as powdered almond, and flowers, such as orange and rose, that need to float freely as they tend to lump together when just steam is passed through them.

Botanical material containing high amounts of esters are precluded from this method since extended exposure to heat will start to break down the esters into its constituent alcohols and carboxylic acids. Hydro-distillation can also be employed under vacuum which reduces the temperature to < 100 °C. This is beneficial in protecting both botanical materials and oils; e.g., Neroli oil, which is sensitive to heat, can be successfully extracted using this method. The water from this process is also used and marketed as “floral waters” also called “hydrosol” or “sweet water”, items such as rosewater, lavender water and orange water.

Figure 1.11: Hydro distillation process in extracting Gaharu essential oil. 62

1.5.2.3 Traditional Method of Producing Oil Using Hydro distillation

Hydro distillation is the simplest and oldest process available for obtaining essential oils from plants. Hydro distillation differs from steam distillation mainly in that the plant material is almost entirely covered with water in the still which is placed on a furnace. An important factor to consider in water distillation is that water present in the tank must always be enough to last throughout the distillation process; otherwise the plant material may overheat and char. In this method, water is made to boil and the essential oil is carried over to condenser with the steam which is formed. Water-distilled oil is slightly darker in colour and has much stronger still notes than oils produced by other method. The stills based on this principle are:

The method is simple in design and extensively used by small-scale producers of essential oils. Care should be taken during distillation of powdered herbs, as they tend to settle on the bottom of the still and get thermally degraded. Also, for plant material that tends to form mucilage and increase the viscosity of the water, the chances of charring are greater. For plant material that has a tendency to agglomerate or to agglutinate into an impenetrable mass when steam is passed through like rose petals, water distillation is the preferred method of oil isolation.

Figure 1.12: Hydro distillation is conventional method used in India.

1.5.2.4 Advantages of Hydro distillation

The advantage of hydro distillation method is material desired distills at a lower temperature that below 100 째C. During water distillation, all parts of the plant charge must be kept in motion by boiling water; this is possible when the distillation material is charged loosely and remains loose in the boiling water. For this reason only, water distillation possesses one distinct advantage. This process permits processing of finely powdered material or plant parts that, by contact with live steam, 64

would otherwise form lumps through which the steam cannot penetrate. Low cost, simplest, easy to construct and suitable for field operation caused water distillation method widely used with portable equipment in many countries.

1.5.2.5 Disadvantages of Hydro distillation

Although hydro distillation is still being used, the process suffers from the following serious drawbacks. Heat control is difficult, which may lead to variable rates of distillation. The process is slow and distillation times are much longer than those of steam distillation. As the plant material near the bottom of the still comes in direct contact with the fire from the furnace, it may char and thus impart an objectionable odour to the essential oil. Oxygenated components such as phenols have a tendency to dissolve in the still water, so their complete removal by distillation is not possible. The distillation process is treated as an art by local distillers, who rarely try to optimize both oil yield and quality.

The prolonged action of hot water can cause hydrolysis of some constituents of the essential oil, such as esters. Oil components like esters are sensitive to hydrolysis while others like acyclic monoterpene hydrocarbons and aldehydes are susceptible to polymerization since the pH of water is often reduced during distillation, hydrolytic reactions are facilitated. As water distillation tends to be a small operation that operated by one or two persons, it takes a long time to accumulate much oil, so good quality oil is often mixed with bad quality oil.

1.5.3

Extraction of Gaharu Essential Oil via Water and Steam Distillation (Alternative 2)

1.5.3.1 Introduction

Although essential oils are produced by different methods such as solvent extraction, expression and critical fluid extraction, most are produced by steam distillation. The proportion of different essential oils extracted by steam distillation is 93% and the remaining 7% is extracted by the other methods.

Essential oils are multi-component chemicals. The mixture of oil compounds that constitute the essential oil comprises polar and non-polar compounds. Some of the compounds in the composite oil are lost in the wastewaters. In the case where the vegetable material and water are mixed in the still, the oil is lost in the water in the still as well as in the aqueous phase of the distillate. During steam distillation of essential oils, the recovery of all organic constituents as the product depends on their partition between water and oil phases of the distillate.

In the majority of cases the oil is less dense than the water and so forms the top layer of the distillate. The very important compounds that make up the chemicals usually referred to in the fragrance industry are the polar compounds. This polarity makes the compounds soluble in water and this solubility is a function of the physical properties of the system such as pressure, temperature and chemical potential.

In many steam distillation processes, plant material is mixed with water and the system is brought to a boil, a process commonly referred to as hydro distillation. The vapor is collected and condensed in order to separate the water from the oil fraction. However, the residual oil dissolved in the water usually causes odor nuisance and is also a waste of the valuable product in the water stream. Studies have been done to quantify and qualify these water-soluble compounds in distillation wastewater.

In order to optimize the recovery of essential oils, the loss of some of the oil components such as the polar components in both the aqueous fraction of the distillate and the water in the still, the water has to be redistilled, a process called cohobation. Redistilling to process wastewater in order to recover the dissolved oil components results in increased utility cost, mainly heating or energy costs.

1.5.3.2 Process and Structure

To eliminate some of the drawbacks of water distillation, some modifications were made to the distillation units. A perforated grid was introduced in the still, to support the plant material and to avoid its direct contact with the hot furnace bottom. When the water level is kept below the grid, the essential oil is distilled by the rising steam from the boiling water. This mode of distillation is generally termed water and steam distillation.

The field distillation unit (FDU), also known as a directly fired type distillation unit, is designed according to the principle of water and steam distillation. The FDU consists of a still or tank made of mild stainless steel with a perforated grid 67

and is fitted directly to a brick furnace. A chimney is connected to the furnace to minimize the pollution at the workplace and also to induce proper fi ring and draft. The plant material is loaded on the perforated grid of the tank and water is filled below it. The tank is connected to the condenser through a vapor line. The water is boiled and the steam vapors pass through the herb, vaporize the oil and get condensed, mostly in a coil condenser by cooling water. The condensate (oil-vapor mixture) is then separated in the oil separator.

These units are simple to fabricate and can be installed in the farmerâ&#x20AC;&#x;s field. Due to their simple construction, low cost and easy operation, FDUs are extremely popular with essential oil producers in developing countries. The furnace is always fueled by locally available firewood or straw. This makes the unit suited for use in remote areas where the raw material is available. This also helps in reducing transportation costs in the production of essential oils.

Figure 13: Local type field distillation unit in India

In water and steam distillation, the steam can be generated either in a satellite boiler or within the still, although separated from the plant material. Like water distillation, water and steam distillation is widely used in rural areas. Moreover, it does not require a great deal more capital expenditure than water distillation. Also, the equipment used is generally similar to that used in water distillation, but the plant 68

material is supported above the boiling water on a perforated grid. In fact, it is common that persons performing water distillation eventually progress to water and steam distillation.

It follows that once rural distillers have produced a few batches of oil by water distillation, they realize that the quality of oil is not very good because of its still notes (subdued aroma). As a result, some modifications are made. Using the same still, a perforated grid or plate is fashioned so that the plant material is raised above the water. This reduces the capacity of the still but affords a better quality of oil. If the amount of water is not sufficient to allow the completion of distillation, a cohobation tube is attached and condensate water is added back to the still manually, thereby ensuring that the water, which is being used as the steam source, will never run out. It is also believed that this wills, to some extent, control the loss of dissolved oxygenated constituents in the condensate water because the re-used condensate water will allow it to become saturated with dissolved constituents, after which more oil will dissolve in it.

Figure 1.14: Water and Steam Distillation Process

1.5.3.3 Disadvantages of Water and Steam Distillation



Due to the low pressure of rising steam, oils of high-boiling range require a greater quantity of steam for vaporization -hence longer hours of distillation.



The plant material becomes wet, which slows down distillation as the steam has to vaporize the water to allow it to condense further up the still.



To avoid that the lower plant material resting on the grid becomes waterlogged, a baffle is used to prevent the water from boiling too vigorously and coming in direct contact with the plant material.

1.5.3.4 Advantages of Water and Steam Distillation over Water Distillation



Higher oil yield.



Components of the volatile oil are less susceptible to hydrolysis and polymerization (the control of wetness on the bottom of the still affects hydrolysis, whereas the thermal conductivity of the still walls affects polymerization).



If refluxing is controlled, then the loss of polar compounds is minimized.



Oil quality produced by steam and water distillation is more reproducible.



Steam and water distillation is faster than water distillation, so it is more energy efficient. Many oils are currently produced by steam and water 70

distillation, for example lemongrass is produced in Bhutan with a rural steam and water distillation system.

1.5.3.5 Improved Field Distillation Units

Due to the limited heating surface available, the rate of steam production in the FDU is always insufficient. This results in prolonged distillation periods and sometimes lower oil yields. Refluxing of oil back into the still due to inadequate steam rate may lead to decomposition reactions and poorer oil quality. Experimental measurements made at the Central Institute of Medicinal and Aromatic Plants (CIMAP), India, have shown that firewood consumption in a conventional field still may be up to 2.5-times greater than that of a modern steam distillation unit operated by an external boiler. This factor may not be critical where fuel supplies are cheap and abundant but, in many developing countries, fuel supplies are getting scarce and costly and low thermal efficiency can directly affect the cost of production.

Considering the previously mentioned demerits of FDUs, designsof economical and improved units with capacities 500-2000 kg per batch are now being preferred (Figure 3). The units are fabricated with high quality mild stainless steel, keeping in view the plant materials to be distilled. The improved distillation unit consists of a cylindrical distillation tank fitted on a square inbuilt boiler (calandria) having smoke pipes which reducesthe heating time of the water, resulting in a high rate of steam generation and lower fuel consumption (20%-30%). Hot flue gasses of the furnace areled through the smoke tubes where they impart heat to the water, thus raising additional steam. The tank is fitted on a specially designed furnace having fire grate, flue ducts and fire door for proper controlling of the firing and draft. The furnace is connected to a chimney of optimum height to maximize the air draft and control the pollution by smoke in the workplace. A similarly designed stainless steel 71

shell and tube-type condenser having higher condensation capacity are used for cooling the vapors. It prevents loss of oil due to improper condensation. The condensed oil-water mixture is then allowed to pass through a specially designed stainless steel oil separator. The separator has an inbuilt baffle to maximize the retention time of the mixture, thereby resulting in no loss of oil with the outgoing water from the separator. The unit also has a chain pulley hoist system with a support structure that makes work easier and saves time during discharge of the distillation waste material from the tank. CIMAP has designed, fabricated and supplied these improved units to entrepreneurs and farmers in different parts of India.

Figure 1.15: CIMAPâ&#x20AC;&#x;s improved field distillation unit

1.5.4

Extraction of Gaharu

Essential Oil via Direct Steam Distillation

(Alternative 3)

1.5.4.1 Introduction 72

As the name suggests, direct steam distillation is the process of distilling plant material with steam generated outside the still in a satellite steam generator generally referred to as a boiler. As in water and steam distillation, the plant material is supported on a perforated grid above the steam inlet. A real advantage of satellite steam generation is that the amount of steam can be readily controlled. Because steam is generated in a satellite boiler, the plant material is heated no higher than 100째 C and, consequently, it should not undergo thermal degradation.

Steam distillation is the most widely accepted process for the production of essential oils on large scale. Throughout the flavor and fragrance supply business, it is a standard practice. An obvious drawback to steam distillation is the much higher capital expenditure needed to build such a facility. In some situations, such as the large-scale production of low-cost oils(e.g. rosemary, Chinese cedar wood, lemongrass, litseacubeba, spike lavender, eucalyptus, citronella, corn mint), the world market prices of the oils are barely high enough to justify their production by steam distillation without amortizing the capital expenditure required to build the facility over a period of 10 years or more

Figure 1.16: Direct Steam Distillation Process

1.5.4.2 Process and Structure

In direct steam distillation, plant material is distilled with steam generated outside the tank in a steam generator or boiler. As in water and steam distillation, the plant material is supported on a perforated grid above the steam inlet. As already noted, the steam in an FDU is at atmospheric pressure and hence its maximum temperature is 100Ë&#x161;C. But, steam in a modern pressure boiler operating at, for example, 50 psi pressure will have a temperature correspondingly higher. Moreover, there is no limitation to the steam generation when an external boiler is used as a source of steam. The use of high-pressure steam in modern steam distillation units permits much more rapid and complete distillation of essential oils.

Steam distillation is preferred when a lot of area is under cultivation and more than one unit is to be installed. Also, for distillation of high boiling oils and hardy materials such as roots and woods like sandalwood, cedar wood and nagarmotha, steam distillation is more efficient. Steam distillation also reduces the time required for the extraction of oils. A charge of Java citronella, which takes up to 5 h in an FDU, is processed within two to 3 h in a steam distillation still. In this method of distillation, steam is generated separately in a steam boiler and is passed through the distillation tank through a steam coil. The plant material is tightly packed above the perforated grid. Steam, containing the oil vapor, is condensed in a tube condenser and is separated in the oil receiver. Fuel costs are generally lower in modern steam distillation units due to higher thermal efficiency at which most of the boilers operate. Capital cost is higher, thus only bigger producers can afford to own such units. Still capacities range from 1 to 3 tons plant material per batch.

Figure 1.17: Boiler-operated steam distillation unit

1.5.4.3 Advantages of Direct Steam Distillation



Amount of steam can be readily controlled.



No thermal decomposition of oil constituents.



Most widely accepted process for large-scale oil production, superior to the other two processes.

1.5.4.4 Disadvantage of Direct Steam Distillation



Much higher capital expenditure needed to establish this activity than for the other two processes.

1.5.5

Extraction of Gaharu

Essential Oil via Cohobation Distillation

(Alternative 5)

1.5.5.1 Introduction

Cohobation is a reinstallation of a liquid by pouring it back repeatedly on the same matter from which it was initially distilled. Many alchemists throughout history have held the curious belief that for a process to be successful it must be repeated many times. So it was common for substances not only to be distilled, but for the products of distillation to be returned to their residue and distilled again, perhaps several hundred times. This was so common a technique that a special piece of apparatus was designed to make the whole process automatic, a flask with return tubes from the neck for the vapor to condense and pass back into the base of the vessel. It was called a blind alembic or a pelican. The latter name derives from the medieval heraldic image representing the ancient legend of the long-necked pelican wounding its breast to feed its young on its blood, the curve of the bird's neck resembling one of the curved return tubes on the flask. The origins of the word cohobation are mysterious, though the OED surmises that it may derive from an Arabic dialect root for "repeat".

Cohobation is a procedure that can only be used during water distillation or water and steam distillation. It uses the practice of returning the distillate water to the still after the oil has been separated from it so that it can be re-boiled. The principal behind it is to minimize the losses of oxygenated components, particularly phenols which dissolve to some extent in the distillate water. For most oils, this level of oil loss through solution in water is less than 0.2%, whereas for phenol-rich oils the amount of oil dissolved in the distillate water is 0.2%-0.7%. As this material is being constantly re-vaporized, condensed and re-vaporized again, any dissolved oxygenated constituents will promote hydrolysis and degradation of themselves or other oil constituents. Similarly, if an oxygenated component is constantly brought in 76

contact with a direct heat source or side of a still, which is considerably hotter than 100째 C, then the chances of degradation are enhanced.

As a result, the practice of cohobation is not recommended unless the temperature to which oxygenated constituents in the distillate are exposed is no higher than 100째 C. In steam and water distillation, the plant material cannot be in direct contact with the fi re source beneath the still; however, the walls of the still are good conductors of heat so that still notes can also be obtained from the thermal degradation reactions of plant material that is touching the sides of the still. As the steam in the steam and water distillation process is wet, a major drawback of this type of distillation is that it will make the plant material quite wet. This slows down distillation as the steam has to vaporize the water to allow it to condense further up the still. One way to prevent the lower plant material resting on the grid from becoming waterlogged is to use a baffle to prevent the water from boiling too vigorously and coming in direct contact with the plant material.

Cohobation basically an improvised methodology of the directly fired type steam and water distillation units for oils which have partial solubility in water. Although most of the essential oils have finite solubility in water, some oils like those of rose, lavender and geranium have comparatively higher solubility. In such extractions, the loss of oil with the outgoing water of distillation can become alarmingly high. This problem can be solved by returning the condensate water from the separator back to the still; this is known as cohobation. It is evident that this cannot be done with steam distillation as the water level inthe still will keep building up due to continuous steam injection.

In a further improved version, a packed column is placed on top of the column for providing mass transfer to the oil-water vapors, so as to increase the concentration of the outgoing condensate and to coalesce the oil droplets in the oil separator. The condenser is placed above the column so that the condensate water

from the separator can be recycled back to the still by means of gravity. Additional heat, if required, can be provided by a closed steam coil immersed in the tank bottom. The condenser is moved above the distillation still so that condensed water from the separator can flow by means of gravity to the still. By limiting the total quantity of water in this closed cycle operation, it is possible to obtain increased yields of essential oils that are more water soluble. It is relevant to point out here that prolonged recirculation of the distillation water allows the various impurities and plant decomposition products to build up in the system. This may sometimes affect the quality of the oil. One must always keep this in mind when considering a cohobation distillation system for any application.

1.5.6

Extraction of Gaharu Essential Oil via Supercritical Fluid Extraction (Alternative 6)

1.5.6.1 Introduction

SFE is used on a large scale for the extraction of some food grade and essential oils and pharmaceutical products from plants. It is relatively rapid because of the low viscosities and high diffusivities associated with supercritical fluids. The extraction can be selective to some extent by controlling the density of the medium and the extracted material is easily recovered by simply depressurizing, allowing the supercritical fluid to return to gas phase and evaporate leaving no or little solvent residues. However, carbon dioxide is the most common supercritical solvent. The main reason for the interest in supercritical fluid extraction (SFE) was the possibility of carrying out extractions at temperature near to ambient, thus preventing the substance of interest from incurring in thermal denaturation. For conventional extraction methods such as hydrodistillation (steam distillation) and solvent extraction, there are few adjustable parameters to control the selectivity of the 78

extraction processes. Therefore, developing alternative extraction techniques with better selectivity and efficiency are highly desirable. Consequently, supercritical fluid extraction (SFE) as an environmentally responsible and efficient extraction technique for solid materials was introduced and extensively studied for separation of active compounds from herbs and other plants. The high solvation power of supercritical fluids (SF) was first reported over a century ago. Demonstration of SFE technology for industrial applications was reported by Zosel at the Max Planck Institute for Kohlemforschung in 1969. In recent years, SFE has received a great deal of attention as the full potential of this technology in analytical applications has begun to emerge. Today, SFE has become an acceptable extraction technique used in many areas. SFE of active natural products from herbal, or more generally, from plant materials has become one of the most important application areas.

1.5.6.2 Supercritical Fluid

Of all the gases and liquids studied, CO2 remains the most commonly used ﬂuid for SFE applications because of its low critical constants (Tc-31.1°C; Pc-72.8 atm), its non-toxic and non-ﬂammable properties, and its availability in high purity with low cost. Supercritical CO2 has good solvent properties for extraction of nonpolar compounds such as hydrocarbons, while its large quadrupole moment also enables it to dissolve some moderately polar compounds such as alcohols, esters, aldehydes and ketones. CO2 is not a very good solvent for high molecular weight and polar compounds. To increase the solubility of such compounds in supercritical carbon dioxide, small amounts (ranging from 0 to 20 mol %) of polar or non-polar co solvents called modifiers may be added. The co solvent interacts strongly with the solute and significantly increases the solubility.

1.5.6.3 Modifiers or co-solvents

A more common practice in SFE is to change the polarity of the supercritical fluid and increase their solvating power towards the analyte of interest by employing polar modifiers (co-solvents). For example, the addition of relatively small percentages (1-10%) of methanol to carbon dioxide expands its extraction range to include more polar analytes. The modifiers can also reduce the analyte-matrix interactions improving their quantitative extraction.

There are two main procedures to study with co-solvents or modifiers in SFE are; the first one, and the most common, accounts for a mixing of the modifier with the CO2 flow while the second mixes the modifier with raw material in the extraction cell. This procedure is always associated to a static extraction step in which the modifier, in intimate contact with the sample matrix, is able to substitute the analyte molecules bound in active centers of the matrix and release them into the supercritical fluid phase.

The application of modifiers probably is the simplest yet the most effective way to obtain a desired polarity of CO2-based fluids. By selecting a modifier or just simply changing the molar ratioof a modifier, one can readily manipulate the properties of the fluids. Usually, addition of asmall amount of a liquid modifier can enhance significantly the extraction efficiency and, consequently, reduce the extraction time. For example, to extract essential oils from aromatic plants, addition of only 0.5 ml of CH2 Cl2 to 500 mg sample in a 2.5-ml SFE cell would reduce the extraction time from 90 to 30 min, while the extraction efficiency was consistent with that obtained in 4 h of hydrodistillation. At least 17 modifiers have been studied in SFE of natural products. Among all the modifiers, methanol is the most commonly used because it is an effective polar modifier and is up to 20% miscible with CO 2. It 80

was believed that high percentages of methanol could disrupt the bonding between the solutes and plant matrices. Ethanol, though not as polar as methanol, may be a better choice in SFE of natural products because of its lower toxicity. Several reports have successfully employed ethanol as a modifier in SFE of a variety of organic compounds from plants. An interesting finding was that ethanol was a more effective modifier for SFE of linuroon, while methanol was better for SFE of diuron from plant materials. Palma et al. used SFE for investigation of the active phenolic compounds in grape seeds. With pure CO2 they obtained the first fraction that mainly contained fatty acids, aliphatic aldehydes and sterols, which had a high degree of antioxidant activity. With 20% methanol-modified CO2 they extracted the second fraction that mainly included epicatechin and gallic acid, which was more agrochemically active. Because SFE allowed the extraction of the compounds without exposure to light and air, they found that the antioxidant properties of the extracts could be safely conserved. There are three common ways to introduce a liquid modifier into the SFE system, using a second pump; using pre-mixed fluids from a cylinder; and direct spiking. Compared with the other two methods, direct spiking a liquid modifier into the SFE cell is the simplest and the most economical method. It also creates less mechanical and reproducibility problems. However, if the spiking method is used, one must be very careful to make sure that the binary fluid is indeed in the supercritical state. Another common problem for the spiking method is that most of the modifier may be flushed out of the sample vessel in the very beginning of the dynamic extraction step, which will likely result in inconsistent results and, therefore, require repeated extractions. Page et al. reported a comprehensive compilation of phase behaviour data for modified CO2 systems.

1.5.6.4 SFE Process

Figure 1.18: SFE Process.

In order to design and develop an SFE process for MAPs with CO2 (possibly assisted by ethanol or water as entrainers), we need to know and optimize:

1. The solubility of the substance of interest 2. The selectivity of this substance with respect to others that are extracted simultaneously 3.

The extraction profiles (such as those in Figure 8)

Figure 1.19: Extraction yield versus at different temperatures

1.5.6.5 Major advantages of SFE technique

Because SFE has several distinct properties, it is regarded as a promising alternative technique to conventional solvent extraction methods. Some of its major advantages are summarized as follows. (1) SFs have relatively lower viscosity and higher diffusivity (the diffusivity for SFs is 104 cm2 s1 and for liquid solvents is 105 cm2s1). Therefore, it can penetrate into porous solid materials more effectively than liquid solvents and, consequently, it may render much faster mass transfer resulting in faster extractions. For instance, with comparable or better recoveries, the extraction time could be reduced from hours or days in a liquid–solid extraction (L– S) to a few tens of minutes in SFE. (2) In SFE, a fresh fluid is continuously forced to flow through the samples; therefore, it can provide quantitative or complete extraction. (3) In SFE, the solvation power of the fluid can be manipulated by changing pressure (P) and:or temperature (T); therefore, it may achieve a remarkably 83

high selectivity. This tunable solvation power of SFs is particularly useful for the extraction of complex samples such as plant materials. One good example is the selective extraction of a vindoline component from among more than 100 alkaloid compounds from the leaves of Catharanthusroseus. (4) Solutes dissolved in supercritical CO2 can be easily separated by depressurization. Therefore, SFE can eliminate the sample concentration process, which usually is time-consuming and often results in loss of volatile components. (5) SFE usually is performed at low temperatures, so it may be an ideal technique to study thermally labile compounds and may lead to the discovery of new natural compounds.

For example, when SFE was used to extract ginger, many undesirable reactions such as hydrolysis, oxidation, degradation and rearrangement could be effectively prevented. Therefore, the common difficulties for quality assessment in classical hydrodistillation could be avoided in SFE. (6) Compared with the 20–100 g of samples typically required in L–S methods, as little as 0.5–1.5 g of samples are needed in SFE methods. It has been reported that from only 1.5 g of fresh plant samples, more than 100 volatile and semi-volatile compounds could be extracted and detected by gas chromatography (GC)–mass spectroscopy (MS), of which more than 80 compounds were in sufficient quantity for accurate quantifications. (7) SFE uses no or significantly less environmentally hostile organic solvents. A SFE method may need no or only a few milliliters of an organic solvent while a typical L–S extraction method would require tens to hundreds of milliliters. (8) SFE may allow direct coupling with a chromatographic method, which can be a useful means to extract and directly quantify highly volatile compounds. (9) In large scale SFE processes, the fluid, usually CO2, can be recycled or reused thus minimizes waste generation. (10) SFE can be applied to systems of different scales, for instance, from analytical scale (less than a gram to a few grams of samples), to preparative scale (several hundred grams of samples), to pilot plant scale (kilograms of samples) and up to large industrial scale (tons of raw materials, such as SFE of coffee beans). In addition to the advantages mentioned above, another distinguished advantage of SFE over conventional methods is that SFE can provide more information pertaining to the extraction processes and mechanisms. One can use such information to quantitatively 84

assess or evaluate the extraction efďŹ ciency and then optimize the process accordingly.

1.6

Enhancement of Essential Oil from Gaharu

1.6.1

Parameters Affecting Yield and Quality of Essential Oils

The yield and quality of essential oil from steam distillation is affected by the various process parameters. It is advisable to keep them in mind while designing such systems. Some of the important parameters are being listed below.

1.6.1.1 Mode of Distillation

The technique for distillation should be chosen considering the boiling point of the essential oil and the nature of the herb, as the heat content and temperature of steam can alter the distillation characteristics. For high boiling oils such as woody oils (e.g. sandalwood, cedar wood) and roots (e.g. Cyperus), the oil should be extracted using boiler-operated steamdistillation. Since the heat content and temperature of steam depend upon its pressure, a change in steam pressure can alter the distillation characteristics. High-boiling constituents of essential oils normally require high pressure steam to distill over. For oil of rose and other floral, the material is generally immersed in water, i.e. hydrodistillation, as flowers tend to aggregate and form lumps which cannot be distilled using water and steam distillation or direct steam distillation. 85

1.6.1.2 Proper Design of Equipment

Improper designing of tank, condenser or separators can lead to loss of oil and high capital investments. The design of the furnace and chimney affects the fi ring and heat control of the distillation rates. Tank height: diameter ratio is important. Similarly the use of a condenser with an improper design and without calculating the heat transfer areas based on the steam generation areas will lead to improper condensation and loss of oil.

1.6.1.3 Material of Fabrication of Equipment

Essential oils which are corrosive in nature should be preferably distilled in stills made of resistant materials like aluminum, copper or stainless steel. The tank still can be made from a cheaper metal like mild steel or galvanized iron, and the condenser and separator can be made from a resistant material like stainless steel. As only vapor is present in the tank still, the rust and other products of corrosion may not be carried over into the oil. This can result in considerable savings in the capital cost of the equipment. Expensive, high-value essential oils like rose, agarwood, kewda, sandalwood and lavender should be distilled in stainless steel systems. Although copper was the most common material of fabrication of distillation stills since ancient times, its availability is getting reduced and with the arrivalof superior alloys like stainless steel, it is slowly disappearing from the scene.

1.6.1.4` Condition of Raw Material

The condition of the raw material is important because some materials like roots and seeds will not yield essential oil easily if distilled in their natural state. These materials have to be crushed, powdered or soaked in water to expose their oil cells. Chopping of plants will also change the packing density of the material when placed in the distillation still. One can pack up to 50% more plant material in the same still after chopping of some aromatic herbs like mint. Air drying and wilting the herb prior to distillation also has considerable effect on distillation. If required, drying of the herbs prior to distillation should be done in shaded areas and the dried material should not be kept in heaps.

1.6.1.5 Time for Distillation

Different constituents of the essential oil get distilled in the order of their boiling points. Thus, the highest boiling fractions will be last to come over when, generally, very little oil is distilling. If the distillation is terminated too soon, the high-boiling constituents will be lost. In many aromatic plants, like vetiver, patchouli, chamomile, sandalwood and agarwood, these high-boiling fractions are valuable due to the quality of their aromas. Thus, the time of distillation must be chosen with due care.

1.6.1.6 Loading of Raw Material and Steam Distribution

Improper loading of the herb may result in steam channeling, causing incomplete distillation. The herb should be evenly and uniformly loaded in the tank without leaving any voids. Excessive filling of plant material may also lead to 87

formation of rat holes which may allow steam to escape without vaporizing the oil. For powdered herbs, a proper stainless steel wire mesh or muslin cloth should be put at the false bottom to prevent plant material from falling into the tank base.

1.6.1.7 Operating Parameters

Proper control of injection rates and pressure in boiler-operated units is necessary to optimize the temperature of extraction for maximal yield. Generally, high-pressure steam is not advisable for the distillation of essential oils. The temperature of the condensate should not be high, as it can result in oil loss due to evaporation. In directly fi red-type FDUs, the fi ring of the furnace should be well controlled as it can result in high flow rates and high condensate temperatures.

1.6.1.8 Condition of Tank and Equipment

The tank and other equipment should not be rusted. If rusted,the tank should be cleaned with dilute caustic solutions. The perforated grids should not be corroded or have large gaps permitting the plant material to settle to the bottom of the tank and emit a burnt odor. The distillation tanks should be well steamed prior to distillation for multiple crop distillation.

1.6.1.9 Purification of Crude Essential Oils

Essential oil as obtained from the oil separator is in crude form. It may have suspended impurities and appreciable moisture content. It might even contain some objectionable constituents which degrade its flavor quality. The presence of moisture and impurities adversely affects the keeping quality of oil and accelerates polymerization and other undesirable reactions. Addition of a drying agent like anhydrous sodium sulphate to the oil, standing overnight followed by filtration will remove the moisture and free the oil of suspended impurities. Use of high-speed centrifugation to clarify the essential oils is common. Essential oils are frequently rectified or re-distilled to remove objectionable constituents. In order to keep the temperature of re-distillation within permissible limits, the process is carried out under vacuum or with the help of steam distillation.

1.6.1.10 Continuous Steam Distillation

Steam distillation units involve manual charging and discharging of plant material from the tank still. These operations are labor intensive and time consuming. To overcome these problems, continuous steam distillation plants have been developed in the Soviet Union and have been in operation since the last couple of decades. These units are being used for distillation of lavender and require negligible manual handing. Capacities of 2 tonnes per hour are quite common. Incoming plant material is first chopped with special ensilage cutters and then conveyed to the top of a tall distillation column by means of a belt conveyor. The movement of material inside the column is by gravity or by special helical screw conveyors. Sometimes two columns in series are used for complete removal of oil. Steam is injected at multiple points in the column. Spent material is continuously ejected out of the bottom of the distillation column by special screw conveyors with a vapor lock which does not allow steam to escape. Fabrication and operation of continuous distillation columns is rather complicated and these have not yet gained acceptance and popularity outside the former Soviet Union. In another development,

containerized distillation is also being used for the distillation of Mentha piperita and lavender in some parts of the United States. In this method, large capacity containers mounted on wheels are attached to a harvester which directly loads the plant material into the containers from the fields (these containers have inbuilt steam coils); these are then taken to the distillation area where steam is directly connected to the coils and the top is closed and connected through a vapor line to the condenser and subsequently to the oil separator.

1.6.2

Pretreatment

The high price of Gaharu essential oil and high demand of this product motivate researcher to develop new extraction methods for higher yield, shorter extraction time and lower processing costs. Therefore, the objective of this section was to study the Gaharu oil yield from various pretreatments on hydro distillation such as aqueous ethanol, dilute acid/alkaline solution, technical enzymes, and ultrasound. Moreover, the subcritical water extraction was investigated and compared the oil yield with traditional method.

The traditional method for essential oil extraction from Gaharu is to soak it in water and follow with hydrodistillation. The effect of various Gaharu pretreatments: ethanol, acid, alkaline, enzymes, and ultrasound, and the effect of subcritical water extraction (SWE) were studied to compare with the traditional method.

The major compositions of Gaharu oil from hydrodistillation were aroma compounds as follow: aristol-9-en-8-one (21.53%), selina-3, 7(11)-diene (12.96%), Ď&#x201E;-himachalene(9.28%), Î˛-guaiene (5.79%), hexadecanoic acid (4.90%) and guaia-

3,9-diene (4.21%). Whereas Gaharu oil from pretreatments with ethanol and ultrasound, and SWE got fatty acid compounds.

Extraction of Gaharu oil using these pretreatments could improve the Gaharu oil yields up to 2 times that of the traditional method. The components of the pretreated sample with diluted acid (H2SO4) at pH 4 gave quite similar results as the traditional method. Therefore, the enhancement of essential oil from Gaharu depends on requirement of type of extracted oil that involved extraction methods.

1.6.3

Soaking

Several studies investigating the effect of solvents on wood cell expansion have been carried out. Soaking solvents play a role in reducing the strength of cell walls and breaking the oil glands. This eases extraction of chemical components. For this purpose, a variety of solvents were applied such as water (Rowell et al. 2005, Stokke& Groom 2006), acid and alkali (Rowell et al. 2005). In commercial processing of Gaharu oil, no standard operating procedures were applied. Distillers usually soak the wood in water for a few days up till two months. To date effects of the immersion technique on the vaporisation temperature and pore size enlargement of Gaharu have not been studied extensively. Most publications focused only on the extraction of chemical compounds from Gaharu (Nor Azahet al. 2008, Wetwitayaklung et al. 2009, Winarni&Waluyo 2009, Nizam&Mashitah 2010). WinarniandWaluyo (2009) extracted Gaharu oil from unsoaked wood. Thus, only a small amount of extractive was obtained. Conversely, numerous chemical components were extracted from agarwood that was soaked in water for more than three days (Wetwitayaklung et al. 2009, Nizam&Mashitah 2010). Therefore, soaking is significant in improving chemical components extracted and yield of essential oil. Hypothetically, the degradation of wood cell wall would enlarge the pore size.

Higher yield was obtained from soaked Gaharu compared withunsoaked samples. The findings of this study were consistent with those of Rashid and Zuhaidi (2011) and Pornpunyapat et al. (2011). They found that soaking could rupture the parenchyma cells, hence facilitating diffusion of oil from the fractured oil glands. Gaharu soaked in acids gave significantly greater yield of oil than the control. This could be due to the effect of acid on the Gaharu structure. Furthermore, distillation of acid- soaked Gaharu samples within the shorter period gave extraordinary oil yield. It could be proven by comparing the current study with research done by Wetwitayaklung et al. (2009) who obtained only 0.2% oil yield from 168 hours distillation of 15 kg of Gaharu soaked in water. Agar wood soaked in acid caused extraordinary enlargement of pore size with average of 18 Âľm. This could provide better condition for the extraction process by facilitating the diffusion of either solvent or chemical component through the enlarged pores. High yield and greatest numbers of chemical compounds were obtained from agar wood soaked in acid.

1.6.3.1

Enzymatic Pretreatment

1.6.3.1.1

Introduction

Enzymes

are proteins that catalyze chemical

reactions.

enzymatic

reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products. Almost all processes in a biological cell need enzymes in order to occur at significant rates. Since enzymes are extremely selective for their substrates and speed up only a few reactions from among many possibilities, the set of enzymes made in a cell determines which metabolic pathways occur in that cell.

Cell-wall degrading enzymes can be used to extract oil by solubilizing the structural cell wall components of the essential oil. This process works to open up cell walls and to break up complex molecules to make maximum oil available for extraction. Enzymatic pretreatment along with high pressure and temperature can significantly increase the oil yield and oil extraction rate. For the enzymatic pretreatment, the buffer solution is used to maintain the stability of pH within the range of pH is 4.5-5.0.

1.6.3.1.2

Methodology

The ground Gaharu were mixed with 1% H2SO4 to remove hemicellulose. The sample was immediately autoclave at 121ยบC and pressure 15 bars for 15 minutes. After that the sample was cooled down until 55ยบC.Then, the sample was neutralized to pH 4.0-4.5 with 5N NaOHto stop pretreatment. The sample was mixed with 12 ml of enzyme mixture which are 5 ml cellulase, 5 mlxylase, 1 ml alcalase and 1 ml rohalase.The enzyme complex breaks down cellulose to beta-glucose. The prepared sample was incubated for 3 days at 55ยบC in a water bath followed by using hydrodistillation. The purpose of incubate is to kills and stop the enzymes reaction. The extracted Gaharu

oil was stored at ambient temperature until analyze the

chemical constituents.

1.6.3.1.3

Enzymatic Process

The cell wall degradation caused by the enzymes increases the permeability to the oil through the cell wall. The uses of enzyme significantly

increased the extraction rate of oil. Enzymatic produced an additional of oil yields with the reduced of extraction time. The pre-treatment process is very crucial to improve the extraction process because it can break the cellular cell wall very effective compare using the traditional hydro distillation which is without pretreatment process in extraction of Gaharu .

Cellulose is a long chain of linked sugar molecules that gives wood its remarkable strength. It is the main component of plant cell walls, and the basic building block for many textiles and for paper. Lignocellulose refers to plant dry matter biomass, so called lignocellulosic biomass. It is the most abundantly available raw material for the production of bio-fuels, mainly bio-ethanol. It is composed of carbohydrate polymers (cellulose, hemicellulose), and an aromatic polymer (lignin).

Cellulose chains can be broken into glucose molecules by cellulase enzymes. This process uses several enzymes at various stages of this conversion. Using a similar enzymatic system, lignocellulosic materials can be enzymatically hydrolyzed at a relatively mild condition 50째C and pH 5, thus enabling effective cellulose breakdown without the formation of byproducts that would otherwise inhibit enzyme activity. All major pretreatment methods, including dilute acid, require an enzymatic hydrolysis step to achieve high sugar yield for ethanol fermentation. Currently, most pretreatment studies have been laboratory based, but companies are exploring means to transition from the laboratory to pilot, or production scale.

Lignocellulose is the major structural component of woody that strengthens woody plant cells. In lignocellulosic materials cellulose, a liner polymer of glucose is associated with hemicellulose and surrounded by lignin seal. Lignin, a complex three-dimensional polyaromatic matrix prevents enzymes from accessing some regions of the cellulose polymers. Crystallinity of the cellulose further impedes enzymatic hydrolysis. Pretreatment of lignocellulosic materials to remove lignin and 94

hemicellulose can significantly enhance the hydrolysis of cellulose. Optimization of the cellulase enzymes and the enzyme loading can also improve the hydrolysis. The performance for the treated samples is being 12% higher than for untreated samples.

1.6.3.1.4

Advantages and Disadvantages of Enzymatic Pretreatment

Enzymatic hydrolysis methods have been used to degrade lignocellulose. Weak acids tend to remove lignin but result in poor hydrolysis of cellulose whereas strong acid treatment occurs under relatively extreme corrosive conditions of high temperature and pH which necessitate the use of expensive equipment. Also, unspecific side reactions occur which yield non-specific by-products. Utility cost of enzymatic hydrolysis is lower than acid or alkaline hydrolysis.

Enzymatic hydrolysis not only gives a high yield of pure glucose, low environmental impact, economize energy on account of the relatively mild reaction conditions at pH 4.8 and temperature 45 – 500ºC, but also avoid using toxic and corrosive chemicals. Enzymatic hydrolysis has to be a promising field in today‟s biotechnological applications which has potential to enhance oil recovery from the oilseeds in shorter time with increased capacity of the equipment‟s.

The enzymatic treatment was successfully performed either during aqueous processing for oil and protein extraction or during conventional oil extraction by pressing. The enzyme mixture of the commercial Celluclast and Novozyme preparation was successfully recycled for five consecutive steps. The efficiency of cellulose hydrolysis decreased gradually with each recycling step.

On the other hand, enzymatic hydrolysis has its own weakness. A hydrolysis time of several days is necessary for enzymatic hydrolysis, whereas a few minutes are enough for acid hydrolysis. The prices of the enzymatic are much higher than sulfuric acid that is used in acid hydrolysis. In acid hydrolysis, the final products such as sugar released do not inhibit the hydrolysis while in enzymatic hydrolysis the sugar released inhibits the hydrolysis reaction.

1.6.3.2

Ultrasonic

1.6.3.2.1

Introduction

Gaharu is a strong woody structure and act as a barrier for essential oil extraction. Ultrasonic extraction is proved to be economical and more effective. The cavitations during ultrasonic extraction have advantage due to ability to penetrate the cellular wall, reduce the particle size and increase the mass transfer between the cell walls and solvent. It is used as alternative extraction technique to increase the extraction yield effectively and decrease the extraction time.

1.6.3.2.2

Principles and Mechanisms of Sonication-assisted Extraction

Sound waves, which have frequencies higher than 20 kHz, are mechanical vibrations in a solid, liquid and gas. Unlike electromagnetic waves, sound waves must travel in a matter and they involve expansion and compression cycles during travel in the medium. Expansion pulls molecules apart and compression pushes them 96

together. The expansion can create bubbles in a liquid and produce negative pressure. The bubbles form, grow and finally collapse. Close to a solid boundary, cavity collapse is asymmetric and produces high-speed jets of liquid. The liquid jets have strong impact on the solid.

Two general designs of ultrasound-assisted extractors are ultrasonic baths or closed extractors fitted with an ultrasonic horn transducer. The mechanical effects of ultrasound induce a greater penetration of solvent into cellular materials and improve mass transfer. Ultrasound in extraction can also disrupt biological cell walls, facilitating the release of contents. Therefore, efficient cell disruption and effective mass transfer are cited as two major factors leading to the enhancement of extraction with ultrasonic power. Scanning electron micrographs (SEM) have provided evidence of the mechanical effects of ultrasound, mainly shown by the destruction of cell walls and release of cell contents. In contrast to conventional extractions, plant extracts diffuse across cell walls due to ultrasound, causing cell rupture over a shorter period.

1.6.3.2.3

Effects of ultrasound characteristics

Ultrasound frequency has great effects on extraction yield and kinetics. However, the effects of ultrasound on extraction yield and kinetics differ depending on the nature of the plant material to be extracted. A small change in frequency can increase the yield of extract about 32% for ultrasound-assisted solid-hexane extraction of pyrethrines from pyrethrum flowers. However, ultrasound has weak effects on both yield and kinetics for the extraction of oil from wood and seeds.

The ultrasonic wave distribution inside an extractor is also a key parameter in the design of an ultrasonic extractor. The maximum ultrasound power is observed in the vicinity of the radiating surface of the ultrasonic horn. Ultrasonic intensity decreases rather abruptly as the distance from the radiating surface increases. Also, ultrasound intensity is attenuated with the increase of the presence of solid particles. In order to avoid standing waves or the formation of solid free regions for the preferential passage of the ultrasonic waves, additional agitation or shaking is usually used.

1.6.3.2.4

Operating conditions

The use of ultrasound allows changes in the processing condition such as a decrease of temperature and pressure from those used in extractions without ultrasound. For solid-hexane extraction of pyrethrines from pyrethrum flowers without ultrasound, extraction yield increases with the extraction temperature and maximum yield is achieved at 66 ºC. With ultrasound, the effect of temperature in the range of 40–66 ºC on the yield is negligible, such that optimal extraction occurs across the range of temperature from 40 to 66 ºC. Therefore, use of ultrasoundassisted extraction is advisable for thermo labile compounds, which may be altered under Soxhlet operating conditions due to the high extraction temperature. However, it should be noted that since ultrasound generates heat, it is important to accurately control the extraction temperature. The sonication time should also be considered carefully as excess of sonication can damage the quality of extracts.

1.6.3.2.5

Advantages and disadvantages of sonication-assisted extraction

Ultrasound-assisted extraction is an inexpensive, simple and efficient alternative to conventional extraction techniques. The main benefits of use of ultrasound in solidâ&#x20AC;&#x201C; liquid extraction include the increase of extraction yield and faster kinetics. Ultrasound can also reduce the operating temperature allowing the extraction of thermo labile compounds. Compared with other novel extraction techniques such as microwave-assisted extraction, the ultrasound apparatus is cheaper and its operation is easier. Furthermore, the ultrasound-assisted extraction, like Soxhlet extraction, can be used with any solvent for extracting a wide variety of natural compounds.

However, the effects of ultrasound on extraction yield and kinetics may be linked to the nature of the plant matrix. The presence of a dispersed phase contributes to the ultrasound wave attenuation and the active part of ultrasound inside the extractor is restricted to a zone located in the vicinity of the ultrasonic emitter. Therefore, those two factors must be considered carefully in the design of ultrasound-assisted extractors.

1.6.3.2.6

Potential applications of sonication-assisted extraction

Ultrasound-assisted extraction has been used to extract nutraceuticals from plants such as essential oils and lipids dietary supplements. Ultrasound can increase extraction yield. Researchers found that ultrasonication was a critical pretreatment to obtain high yields of oils from almond, apricot and rice bran. The yield of oil extracted from soybeans also increased significantly using ultrasound. For ultrasound-assisted extraction of saponin from ginseng, the observed total yield and saponin yield increased by 15 and 30%, respectively.

Ultrasound can increase extraction kinetics and even improve the quality of extracts. Rice bran oil extraction can be efficiently performed in 30 min under highintensity ultrasound either using hexane or a basic aqueous solution. Extraction rates of carvone and limonene by ultrasound-assisted extraction with hexane were 1.3â&#x20AC;&#x201C;2 times more rapid than those by the conventional extraction depending on temperature. Furthermore, the yield and quality of carvone obtained by the ultrasound-assisted extraction were better than those by a conventional method.

The ultrasound was also applied to the cartridge of a Soxhlet extraction for the extraction of total fat from oleaginous seeds such as sunflower, rape and soybean seeds. The use of ultrasound reduced the extraction at least to half of the time needed by conventional extraction methods without any change in the composition of extracted oils. Ultrasound-assisted extraction of ginseng saponins occurred about three times faster than traditional Soxhlet extraction. Ultrasound-assisted extraction was considered as an efficient method for extracting bioactive compounds from Solviaofficinalis

and

Hibiscus

tiliaceus

flowers,

antioxidants

from

Rosmarinusofficinalis and steroids and triterpenoids from Chresta spp. The use of ultrasound as an adjunct to conventional extraction provides qualitatively acceptable tocols from amaranthuscaudatus seeds but much more quickly, more economically and using equipment commonly available.

1.6.3.2.7

The Role of Ultrasonic as Physical Treatment of Raw Materials

Physical force exerted by ultrasonic wave caused a tremendous particle size reduction. This reduction in size yielded an increase in the ratio of surface area to volume ratio of the lignocellulosic materials. This would be beneficial since it would expose more cellulose molecules that were available for chemical reactions. The heterogeneous reactions involving polymeric cellulose in the solid phase and the rest

100

of the reactants in the aqueous phase required that the cellulose be physically exposed to the reactants in the aqueous phase.

Ultrasonic exerts its effects by means of generating bubbles inside a liquid medium, termed cavitation. The sound energy created by the ultrasonic probe acted as a source of vibrational wave energy that worked on the molecule within the liquid. This energy produced alternate compressions and stretches towards the liquid medium that produced bubbles. These bubbles are exposed to the same vibrational stresses within the liquid medium, and would grow and eventually collapse violently. During this collapse, theoretical temperature could reach over 5,000 K and pressure of up to 2,000 atmospheres. The uniform ultrasonic field creates millions of bubbles throughout the liquid and destroyed thousands of times per second. This local extreme of heat and pressure could cause the bonds within the biomass structure to break, resulting in tom and shattered structures.

The smaller the size of particles, the higher was the surface area. Due to this higher surface area, the enzyme or acid would have an easier access to hydrolyze the cellulose. Moreover, it is likely that the local high temperature would provide some energy for chemical reactions to occur, including the hydrolysis of cellulose into glucose. Ultrasonic treatment has significantly increased the enzyme hydrolysis of cellulose in woodchips. Based on statistical analysis, 20 minutes was the optimum duration for ultrasonic. The 30 minutes treatment did not give significant increase.

The amount of sugar released by the enzyme hydrolysis step in this study still required optimization in terms of the process conditions such as longer incubation period and higher enzyme cellulase concentration. Different cellulase sources should also be considered. Possibly the use of other sources of cellulase enzyme such as Trichodenna sp. could perform better than the results achieved in this research using cellulase enzyme from Aspergillusniger. Nevertheless, the impact of ultrasonic in the glucose production from lignocellulosic material has been shown here.

101

CHAPTER 2

PROCESS SYNTHESIS AND FLOW SHEETING

2.0

Synthesis of Process Flow Diagram

2.0.1

Process Flow Diagram

Process synthesis and flow sheeting is an essential task in extraction of essential oil of Gaharu plant design. It involves flow sheet generating. The flow sheet is a link and layout of each unit operation to produce final products from raw materials. The main raw material used in this plant is Gaharu chip. This plant design is produce 450 Liters essential oil of Gaharu per year. The operation days in a year are 365 days.

The plant will be operating in batch. Therefore, the calculation performed is production for each day and one batch per day based on the amount of Gaharu supply in Malaysia is limited. With these procedures, the best flow sheet for the process is chosen with a systematic method to ensure that all alternative have been screened and the best decision has been made.

102

The process is divided into two parts where the first part is the pretreatment of the Gaharu . After the pretreatment, Gaharu will be the basis of the extraction essential oil for production process.

2.0.2

Process Description

The selected batch extraction essential oil process of Gaharu including two main parts which are pretreatment of Gaharu and extraction essential oil of Gaharu using steam distillation method. The pretreatment process of Gaharu is started it operation in the autoclave which the mixture is sterilized by heating up to 121 ºC and pressure 15 bar for 15 minutes. Before that, Gaharu need to submerge in the 1 % sulphuric acid. The tank has heating jacket to increase the temperature by the steam. After sterilization process has done, the pressure will be release back to 1 bar before transfer out the mixture to the cooler.

After the mixture has been cooled to desired temperature, it will move the mixture to the incubator using pump. In this tank, 5N sodium hydroxide added to neutralize the mixture to pH 4 – 4.5 and 36 kg of enzyme consist of 15 kg cellulose, 15 kg xylase, 3 kg alcalase and 3 kg rohalase is added. The enzyme complex breaks down cellulose to beta-glucose. The mixture is stir and incubated for 3 days. The temperature will be maintained at 55 ºC by the heating jacket.

Next will be extraction oil of Gaharu using steam distillation. The mixture already incubates for three days will be sent to steam extraction unit. Then, steam from the boiler is injected into the distillation column. Gaharu oil and water will vaporize and 103

the waste is maintained at the bottom of distillation column. The time for steam extraction is 15 hours. In condenser, the vaporize water and oil will be condense into the liquid form. Lastly, Gaharu oil is separate from the water in separator funnel.

Equipment selection is very important and has to be chosen carefully to maintain the profitability, safety and environment factors of the plant. Decision in equipment selection is done based on the process of our product. This ensures the process to go on smoothly to obtain product with high purity and quality.

104

Figure 2.1: Extraction of Gaharu Essential Oil with Capacity of 450 Litres per Year

SP-2

SP-6

SP-1

P-4 / HX-101

P-5 / PM-101

Cooling

Fluid Flow

SP 6 HOT OUT

SP-3

P-1 / V-101 Blending / Storage

SP-5

GAHARU

P-8 / HX-102 SP-4

SP-10

P-2 / V-102

Heat Exchanging

SP 13

SP-11

Vessel Procedure

PRODUCT COOL IN

P-3 / GR-101

W AT ER

Grinding P-9 / V-105 Decanting

P-6 / V-103 SP-8

SP-9

Blending / Storage

SP-14 P-7 / V-104 Batch Distillation

105

2.1

Basis for Equipment Selection

Table 2.1 gives the plant equipment and its function for the extraction of Gaharu oil.

Table 2.1: Plant Equipment and Its Functions

Unit Mixing Tank

Functions -

To mix and dilute 50% concentrated H2SO4 solution to become 1% concentrated H2SO4 solution.

Autoclave

To sterilize the grind Gaharu using 1% concentrated H2SO4 solution under specific condition.

Cooler

To cold the grind Gaharu to desired temperature.

Incubator

To neutralize the grind Gaharu using 5M NaOH concentration and kept it under specific condition before proceed next stages.

Steam Extraction

To extract the desired compound under specific condition.

To condenses a compound involved from vapour state to

Unit Condenser

liquid state. Boiler

To heat water in order to generate steam.

Oil Water Separator

To separate essential oil of Gaharu from water.

106

Part 1: Pretreatment of whole Gaharu

2.1.1

Mixing Tank with Impeller

Figure 2.2: Mixing tank with impeller

Before enter first stage of pretreatment of whole Gaharu , mixing tank was used for dilute 50% concentrated H2SO4 solution to become 1% concentrated H2SO4 solution. The general purpose of the mixing tank is to disperse the substance into the bulk fluid to ensure a uniform mixture before it reaches the next process tank. Mixing tanks are typically used Impeller is built in a mixing tank to enable mixing.

An impeller is a rotor inside a tube or conduit used to increase (or decrease in case of turbines) the pressure and flow of a fluid. There are two types of impellers, depending on the flow regime created: The axial flow impeller and the radial flow impeller.

The radial flow impellers impose essentially shear stress to the fluid, and are used, for example, to mix immiscible liquids or in general when there is a deformable 107

interface to break. Another application of radial flow impellers are the mixing of very viscous fluids. An example of radial flow impeller is the Rushton Turbin.

The axial flow impellers impose essentially bulk motion, and are used on homogenization processes, in which increased fluid volumetric flow rate is important. An example of axial flow impeller is the Marine type impeller. There are three types of mechanical mixing which are propeller mixer, turbine mixer and paddle mixer.

Figure 2.3: Mixing - Axial flow and radial flow

Table 2.2: Differences between Propeller Mixer, Turbine Mixer and Paddle Mixer

Features Device

Propeller Mixer

Turbine Mixer

Paddle Mixer

Fix to a rotating

Constant blade angle

Consist of two or more

vertical, horizontal

with respect to a

blades mounted on a

or inclined shaft.

vertical plane, over its

vertical or inclined

entire length

shaft.

or over finite sections. Operation

Operate at high

Operation is

The turbulence spreads

speed without the

analogous to that of

outward very slowly

108

use of a gearbox.

a centrifugal pump

and imperfectly into the entire contents of

working in a vessel against negligible back pressure.

Advantage

the tank; hence, circulation of the liquid is slow.

When it operated at

Simple device and low

mechanical losses in

sufficiently, high

cost. Used for liquids

transmission, used

rotational speeds,

with viscosities only up

for mixing

both radial and

to about 1,000 cp.

liquids with

tangential flows

viscosities up to

become pronounced,

2000 cp.

along with vortex formation.

Disadvantage

Higher cost, the

Need installation of

Small pumping

sensitivity of

baffles to ensure a

capacity (a slow axial

operation to the

more uniform flow

flow), which does not

vessel geometry and

distribution

provide a thorough

its location within

throughout the mixing

mixing of the tank

the tank.

vessel.

volume.

Illustration

109

Based on the table above, propeller mixer is more suitable for the plant. The viscosities of propeller mixer can go up to 2000 cp compare to another mixer. It also can operate at high speed so this will short cut the time for mixing.

2.1.2

Autoclave

Figure 2.4: Autoclave

In the first stage of pretreatment of Gaharu , autoclave was used to sterilize the grind Gaharu using 1% concentrated H2SO4 solution at 15 bar and 121째C. Generally, the autoclave is a steam-pressure sterilizer which is a large, heavy-walled chamber with a steam inlet and an air outlet. It can be sealed to force steam accumulation. An autoclave applies both heat and pressure to the workload placed inside of it. Typically, there are several classes of autoclave. However we decide to select those pressurized with steam process workloads which can withstand exposure to water, while circulating heated gas provides greater flexibility and control of the heating atmosphere.

The barometric pressure of normal atmosphere is about 15 lb to the square inch. Within an autoclave, steam pressure can build to 15 to 30 lb per square inch above 110

atmospheric pressure, bringing the temperature up with it to 121 to 123°C. Steam is wet and penetrative to begin with, even at 100°C (the boiling point of water). When raised to a high temperature and driven by pressure, it penetrates thick substances that would be only superficially bathed by steam at atmospheric pressure. Under autoclave conditions, pressurized steam kills bacterial endospores, vegetative bacilli, and other microbial forms quickly and effectively at temperatures much lower and less destructive to materials than are required in a dry-heat oven (160 to 170°C).

Table 2.3: Pressure-Temperature-Time Relationship in Steam-Pressure Sterilization

Under routine conditions, properly controlled, steam-pressure sterilization can be accomplished under specific conditions of pressure, time, and temperature.



15 to 20 lb of steam pressure



121 to 125°C (250 to 256°F) steam temperature



15 to 45 minutes, depending on the nature of the load

111

Figure 2.5: Illustration of steam-pressure sterilizer

2.1.3

Cooler

Figure 2.6: Cooler

The cooler is a type of heat exchanger. A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. The media may be separated by a solid wall, so that they never mix, or they may be in direct contact. 112

The transfer of heat to and from process fluids is an essential part of the most chemical plant. The most commonly used type of heat-transfer equipment is shell and tube heat exchanger. The primary objective of a heat exchanger is to determine the surface area required for the specified duty (rate of heat transfer) using temperature differences.

In this plant, heat exchanger is used as a device to allow heat transfer between a hot stream and a cold stream and also between stream and external utilities like steam and cooling water to ensure the optimum temperature is achieved for reaction to take place. The type of heat exchangers used is the shell pass and two tube passes with a split-ring floating head type.

Shell and tube heat exchangers consist of a series of tubes. One set of these tubes contains the fluid that must be either heated or cooled. The second fluid runs over the tubes that are being heated or cooled so that it can either provide the heat or absorb the heat required. A set of tubes is called the tube bundle and can be made up of several types of tubes: plain, longitudinally finned, etc. Shell and tube heat exchangers are typically used for high-pressure applications (with pressures greater than 30 bar and temperatures greater than 260 째C). This is because the shell and tube heat exchangers are robust due to their shape.

113

Figure 2.7: Shell and tube heat exchangers

Figure 2.8: Shell and Tube Cooler

2.1.4

Incubator

Figure 2.9: Incubator 114

Incubator is use to assure an even or stable temperature. By immersing the object in water of a given temperature it is used to cool, to heat and to maintain samples at a certain temperature and this is done in a controlled manner. It is often essential to keep a liquid mixture at an exact temperature without a gradient of heat that the bottom being hotter than the top. Therefore, the temperature is same at all part of the water bath.

Incubator consists of four basic elements: the heater shell, the fire tube, the process coil, and the bath media. Heat is transferred from the fire tube to the bath and from the bath to the process coil. A bath solution is heated by a fire tube style burner submerged at the bottom of the heater vessel. The bath solution then heats a submerged process coil, in which the flowing process medium is then heated. Water-glycol mixtures are very common solutions for most low temperature heating applications, and can typically be used up to 121ยบC. Salt melts can be used to meet the higher operating temperature requirements in some specialized applications.

The advantage is that the water in the bath presents the heated material with a constant temperature that will not exceed 100oC, the boiling point of water so that over heating or scorching is avoided. The water bath is slightly more complex the double boiler as the temperature can be controlled through sensors to within a degree of the desired temperature. The resulting process heating is indirect, safe and reliable. A process bath heater is a simple and safe method for indirectly heating various process mediums.

115

Figure 2.10: Process of incubator

Figure 2.11: Illustration of Incubator

Part 2: Extraction essential oil of Gaharu

2.1.5

Steam Extraction Unit

116

Figure 2.12: Steam Distillation

When steam distillation is used in the manufacture and extraction of essential oils, the botanical material is placed in a still and steam is forced over the material. The hot steam helps to release the aromatic molecules from the plant material since the steam forces open the pockets in which the oils are kept in the plant material. The molecules of these volatile oils then escape from the plant material and evaporate into the steam.

The temperature of the steam needs to be carefully controlled - just enough to force the plant material to let go of the essential oil, yet not too hot as to burn the plant material or the essential oil. The steam which then contains the essential oil is passed through a cooling system to condense the steam, which form a liquid from which the essential oil and water is then separated.

The steam is produced at greater pressure than the atmosphere and therefore boils at above 100 degrees Celsius which facilitates the removal of the essential oil from the plant material at a faster rate and in so doing prevents damage to the oil.

117

Figure 2.13: Cross Section of Steam Distillation

Figure 2.14: Steam Distillation Still

118

2.1.6

Condenser

Figure 2.15: Condenser

Condenser in its simplest terms is a heat transfer device which reduces a thermodynamic fluid from its vapour phase to its liquid phase. In the condenser the latent heat of condensation is conducted to the cooling medium flowing through the cooling tubes. A condenser rejects heat to the environment to turn vapour into liquid. Ideally a vapour enters the condenser as saturated vapour, meaning it's at the boiling point. The vapour condenses and leaves the condenser at saturated liquid also at the boiling temperature.

The main use of a condenser is to receive exhausted steam from a steam engine or turbine and condense the steam. The benefit being that the energy which would be exhausted to the atmosphere is utilized and the engine turbine exhaust conditions are stable and controllable. A steam condenser generally condenses the steam to a pressure significantly below atmospheric. This allows the turbine/engine to do more work. The condenser also converts the discharge steam back to feed water which is returned to the steam generator boiler.

119

Figure 2.16: Process of surface condenser

The condenser that we select for this plant is a surface condenser. The surface condenser is the most important type of condenser in present day use. Its main functions are to condense low pressure steam exhausted from turbines and also to maintain the vacuum at the exhaust end of the turbines. It has the advantage that the condensate and the cooling water are entirely separate. The condensate is thus delivered to the boiler feed system as distilled water and is at a higher. This type of condenser has a large area of cooling surfaces compared to the system volume. The steam passes through the condenser and condenser on contact with the cooling surfaces. The condensate collects in the bottom of the condenser from where it is pumped away to the boiler feed system.

Figure 2.17: Illustration of Condenser 120

2.1.7

Boiler

A boiler may be classified as either a steam boiler or hot water boiler. The vessels are the same and the boiler trim (controls & piping) determine the use of the vessel. A steam boiler must maintain a water level covering the top of the heating (tube) surfaces while leaving room for steam production. A hot water boiler is completely full of water over the top of the boiler into the expansion tank.

Table 2.4: Differences between Fire-tube Boiler and Water Tube Boiler

Features Design

Fire-tube boiler -

Water tube boiler

Consist of numbers of tubes

Water is heated inside tubes

through which hot gasses are

and the hot gasses surround

passed.

them.

These

hot

gas

tubes

are

Designed to circulate hot

immersed into water, in a

combustion gases around the

closed vessel.

outside of a large number of

Fire tubes or hot gas tubes

water filled tubes.

heated up the water and convert the water into steam and the steam remains in same vessel. -

Can produce maximum 17.5 kg/cm2 and with a capacity of 121

9 Metric Ton of steam per hour. Advantages

Compact in construction.

Fluctuation of steam demand

achieved

Low cost.

using

numbers of water tubes.

can be met easily. -

Larger heating surface can be

Due to convectional flow, movement of water is much faster than that of fire tube boiler; hence rate of heat transfer is high which results into higher efficiency.

Very high pressure in order of 140 kg/cm2 can be obtained.

Disadvantages

Cannot produce steam at very high pressure as the water and steam are in same vessel.

Requires long time for rising steam at desired pressure.

Not compact in construction.

Highly cost.

Size is a difficult for transportation and construction.

Steam received from fire tube boiler is not very dry.

122

Illustration

Since operating pressure is low at 0.3 MPa, fire tube boiler would be suitable to be selected in this process.

Figure 2.18: Fire-tube Type Steam Boiler

123

2.1.8

Oil Water Separator

Figure 2.19: Oil Water Separator In the Gaharu extraction plant, one of the phases will be aqueous, and the other is Gaharu essential oil constituents. All of these solvents form a clear delineation between the two liquids. The two layers formed are usually known as the organic and aqueous phases. Most organic solvents float on top of an aqueous phase, though important exceptions are most halogenated solvents. The organic solvent used for the extraction must not react with the substance to be extracted or with water.

The oil are separated forms a film of oil that is automatically skimmed off. A baffle or oil dam prevents the collected oil from entering the outlet weir. The oil collects in a drum below the separation unit.

The water stream passes through a series of weirs to a filtration chamber where any remaining suspended neutral gravity solids are removed before final filtration and exit.

124

Figure 2.20: The Cutaway Section of Oil Water Separator

2.2 Manual Material and Energy Balance

2.2.1

Manual Calculation for Material Balance

The procedure of doing manual material balance is based on the shortcut method in Systematic Methods of Chemical Process Design [1]. The calculations involve unit operation by unit operation problem solving. All the manual calculations are calculated using Microsoft Excel 2000. The spreadsheets created ensure the easy and fast editing of calculations and formulas. Some assumptions have been made to enable the shortcut calculations viable. The design-based assumptions are:

i. Whole Gaharu used for pretreatment are in a weight ranges from 600-630 kg. ii. 600 kg of grind Gaharu that undergoing pretreatment will produce 600 kg Gaharu . iii. The basis is extraction of Gaharu oil produce 1.26 kg/day.

125

Gaharu contain 0.006 % of Î˛-agarofuran (C15H24O), 0.006 % of nor-

iv.

ketoagarofuran (C15H24O), 0.047 % of agarospirol (C15H26O), 0.04 % of jinkoh-eremol (C15H26O), 0.029 % of kusunol (C15H26O), 0.024 % of dihydrokaranone (C10H16O), 0.058 % of oxo-agarospirol (C10H16O) and 99.79 % of cellulose (C6H10O5). v. Compositions of Gaharu that consider inside the calculation are 0.012 % of C15H24O, 0.116 % C15H26O and 0.082 % of C10H16O. vi. Neglect mass flow rate of enzyme at Stream P-7. vii. All calculations are performed in the unit of kg/day. viii.

The system is steady state, so the accumulation is equal to zero.

ix. All components in the system behave as ideal condition. x. No leakage in the pipes and vessels in the system. xi. Plant operates 365 days per year and 1 batch was run per day. xii. The total input of any substance to a pump, agitating vessel or heat exchanger is assumed equal to the total output of the substance where no reaction occurs in those devices.

Basis Calculation: Minimum amount of Gaharu oil produced 459.9 kg /yr =

459.9 kg yr

1 yr 365 days

1.26

Manual calculation of mass balance can refer below. Summary of manual calculation mass flow rate and simulation mass flow rate is shows in Table 2.2 as below.

126

2.2.2

Manual Calculation of Mass Balance

0.006 % Î˛-agarofuran, C15H24O 0.006 % nor-ketoagarofuran, C15H24O 600 kg/day Gaharu type A

Extraction Plant

0.047 % agarospirol, C15H26O 0.04 % jinkoh-eremol, C15H26O 0.029 % kusunol, C15H26O 0.024 % dihydrokaranone, C10H16O 0.058 % oxo-agarospirol ,C10H16O

A) Chemical formula of Gaharu

99.79 % cellulose,C6H10O5

C component 15(0.00012) + 15(0.00116) + 10(0.00082) + 6(0.9979) = 6.014

H component 24(0.00012) + 26(0.00116) + 16(0.00082) + 10(0.9979) = 10.025

O component 1(0.00012) + 1(0.00116) + 1(0.00082) + 5(0.9979) = 5

So, chemical formula of Gaharu = C6.014H10.025O5

127

B) Mass flow rate out for each component

C15H24O

x 600 kg/day = 0.036 kg/day

C15H24O

x 600 kg/day = 0.036 kg/day

C15H26O

x 600 kg/day = 0.282 kg/day

C15H26O

x 600 kg/day = 0.174 kg/day

C10H16O

x 600 kg/day = 0.144 kg/day

C10H16O

x 600 kg/day = 0.348 kg/day

C6H10O5

x 600 kg/day = 598.74 kg/day

x 600 kg/day = 0.24 kg/day

C) Molar flow rate

Molecular weight of compounds Gaharu (C6.014H10.025O5) = 162.07 kg/kmol C15H24O = 220 kg/kmol C15H26O = 222 kg/kmol C10H16O = 152 kg/kmol C6H10O5 =162 kg/kmol 128

Molar flow rate in MW of Molar flow rate = =

= 3.702 kmol/day

Molar flow rate out C15H24O

0.000164 kmol/day

C15H24O

0.000164 kmol/day

C15H26O

0.00127 kmol/day

C15H26O

0.00108 kmol/day

C15H26O

0.000784 kmol/day

C10H16O

0.000947 kmol/day

C10H16O

0.002289 kmol/day

C6H10O5

3.696 kmol/day

D) Table of energy and mass balance

129

In Component

Out

Molar flow

Mass flow rate

Molar flow rate

Mass flow rate

rate

(kg/day)

(kmol/day)

(kg/day)

(kmol/day) C6.014H10.025O5

3.702

600

C15H24O

0.000164

0.036

0.000164

0.036

0.00127

0.282

0.00108

0.24

0.000784

0.174

0.000947

0.144

0.002289

0.348

3.696

598.74

Î˛-agarofuran C15H24O Norketoagarofuran C15H26O agarospirol C15H26O jinkoheremol C15H26O kusunol C10H16O dihydrokaranone C10H16O oxo-agarospirol C6H10O5

Calculation of Heat Capacities:

Koppâ&#x20AC;&#x;s Rule:

130

Cp C6.014H10.025O5 = 6.014(7.5) +10.025(9.6) +5(17) = 226.35 J/mol˚C =1.396 kJ/kg oC CP C15H24O = 15(12) +24(18) +25=637 J/mol˚C =2.895 J/goC CP C15H26O =15(12) +24(18) +25=673 J/mol˚C =3.032 J/goC CP C10H16O =10(12) +16(18) +25=433 J/mol˚C =2.849 J/goC Cp H2SO4 = 1.42 J/goC Cp NaOH = 28.230 J mol−1 K−1 = 0.706 J/goC Cp H2O (l) = 4.184 J/goC Cp H2O (vap) @ 327̇˚C = 2.015 J/goC Cp C6H10O5 (s) =6(7.5) +10(9.6) +5(17) =226 J/mol˚C=1.395 J/goC Cp Na2SO4= 2(12) +26+4(17) =118 J/mol˚C =0.831J/goC

Part 1: Pretreatment of Gaharu

2.2.2.1 Mixing Tank

131

Stream P-2

X H2O = 1 Y H2O = 1 Mixing Tank

Stream P-1

Stream P-3

X 50 % H2SO4 = 0.5 X H2O = 0.5

X 1 % H2SO4 = 0.01 X H2O = 0.99

Y 50 % H2SO4 = 0.155 Y H2O = 0.845

Y 1 % H2SO4 = 0.157 Y H2O = 0.843

Additional Data: Density of 50 % H2SO4 = 1.395 g/cm3 Density of 1% H2SO4 = 1.00 g/cm3 Density of H2O = 1.00 g/cm3

Inlet Component Stream P-1

Outlet Stream P-2

Stream P-3

Mass

Volume

Mass

Volume

Mass

Volume

flow rate

(kg/day)

(L/day)

(kg/day)

(L/day)

(kg/day)

(L/day)

50 % of H2SO4

108

77.419

1 % of H2SO4

H2O

5292

5346

132

2.2.2.2 Autoclave Stream P-3

X H2SO4 = 0.01 X H2O = 0.99 Y H2SO4 = 0.0019 Y H2O = 0.9981

Stream P-4

Autoclave

Stream P-5

X C6.014H10.03O5 = 1 X C6.014H10.03O5 = 0.1 X H2SO4 = 0.009 X H2O = 0.891

Y C6.014H10.03O5 = 1

Y C6.014H10.03O5 = 0.012 Y H2SO4 = 0.002 Y H2O = 0.986 Component

Inlet

Outlet

Stream P-3

Stream P-4

Stream P-5

Mass flow rate

(kg/day)

C6.014H10.03O5

600

H2SO4

H2O

5346

133

2.2.2.3 Cooler

Stream P-5

Cooler

Stream P-6

X C6.014H10.03O5 = 0.1 X H2SO4 = 0.009 X H2O = 0.891

Y C6.014H10.03O5 = 0.012 Y H2SO4 = 0.002 Y H2O = 0.986

Mass balance of cooler for Stream P-5 and Stream P-6 are same.

Inlet

Outlet

Stream P-5

Stream P-6

Mass flow rate (kg/day)

C6.014H10.03O5

600

H2SO4

H2O

5346

Component

134

2.2.2.4 Incubator

Stream P-7

Incubator

Stream P-8

Stream P-6

X NaOH = 0.169 X H2O = 0.831

X C6.014H10.03O5 = 0.1 X H2SO4 = 0.009 X H2O = 0.891

Y NaOH = 0.084 Y H2O = 0.916

Stream P-9

Y C6.014H10.03O5 = 0.012 Y H2SO4 = 0.002 Y H2O = 0.986

Calculation

X C6.014H10.03O5 = 0.096 X Na2SO4 = 0.012 X H2O = 0.892 Y C6.014H10.03O5 = 0.011 Y Na2SO4 = 0.002 Y H2O = 0.987

Neutralization: H2SO4 (l) + 2NaOH (l) Na2SO4 (s) + 2H2O (l)

Assumption: Complete neutralization, reaction happens at T=25˚C

For H2SO4, No. of mol of H2SO4 =

= 550.577 mol 135

For 5M NaOH, No. of mol of NaOH = 2 x 550.577 mol = 1101.15 mol Density of 5M NaOH = 1.182

at 25 °C

Molecular weight of NaOH= 39.997 Volume of 5M NaOH =

= 220.231 L

Mass of 5M NaOH = = 220.231 L x 1.182

= 260.313 ṁNaOH = = 1101.15 mol x 39.997 ṁH2O = 260.313

– 44.043

= 44.043

= 216.27

For Na2SO4, Molecular weight of Na2SO4 = 142.04 No. of mol of Na2SO4 = 550.577 mol ṁNa2SO4 = = 550.577 mol x 142.04

= 78.204 136

For H2O, No. of mol of NaOH = 2 x 550.577 mol = 1101.15 mol 盪？20 = no of mol x molecular weight = 1101.15 mol x 18.0153

= 19.834

Assumption: Neglect mass flow rate of enzyme at Stream P-7.

Inlet Component

Outlet

Stream P-6

Stream P-8

Stream P-9

Mass flow rate

(kg/day)

C6.014H10.03O5

600

H2SO4

NaOH

44.043

Na2SO4

78.204

H2O

5346

216.27

5582.10

137

Part 2: Extraction of Gaharu Oil 2.2.2.5 Condenser

Stream P-10

Condenser

Stream P-11

X C15H24O = 1.44x10-6 X C15H26O = 1.392x10-5 X C10H16O = 9.84x10-6 X H2O = 0.99997

Y C15H24O = 1.178x10-7 Y C15H26O = 1.129x10-6 Y C10H16O = 1.165x10-6 Y H2O = 0.9999

Mass balance of condenser for Stream P-10 and Stream P-11 are same.

Inlet

Outlet

Stream P-10

Stream P-11

Mass flow rate (kg/day)

C15H24O

0.072

C15H26O

0.696

0696

C10H16O

0.492

H2O

50 000

Component

138

2.2.2.6 Boiler

Stream P-12

Boiler

Stream P-13

X H2O = 1

Y H2O = 1

Mass balance of boiler for Stream P-12 and Stream P-13 are same.

Inlet

Outlet

Stream P-12

Stream P-13

Mass flow rate (kg/day)

H2O (l)

50 000

H2O (v)

50 000

Component

139

2.2.2.7 Extraction Unit

X C6.014H10.03O5 = 0.096 X Na2SO4 = 0.012 X H2O = 0.892 Stream P-9

Y C6.014H10.03O5 = 0.011 Y Na2SO4 = 0.002 Y H2O = 0.987

Extraction Unit

Stream P-13

Stream P-10

X C15H24O = 1.44x10-6 X C15H26O = 1.392x10-5 X C10H16O = 9.84x10-6 X H2O = 0.99997

X H2 O = 1 Y H2 O = 1 Stream P-14

X Na2SO4 = 0.012 X C6H10O5 = 0.0917 X H2O = 0.892

Y C15H24O = 1.178x10-7 Y C15H26O = 1.129x10-6 Y C10H16O = 1.165x10-6 Y H2O = 0.9999

Y Na2SO4 = 1.753x10-3 Y C6H10O5 = 0.012 Y H2O = 0.986 Inlet Component

Outlet

Stream P-9

Stream P-13

Stream P-10

Stream P-14

mass

(kg/day)

C6.014H10.03O5

600

H2O (l)

5582.10

H2O (v)

50 000

0 140

Na2SO4

78.204

C6H10O5

598.74

C15H24O (v)

0.072

C15H26O (v)

0.696

C10H16O (v)

0.492

Table 2.5: Summary of Mass Flow Rate for Each Stream

Stream

Mass Flow Rate (kJ/day)

Mass Flow Rate (kg/day)

Differences

Manual calculation

Simulation output

(%)

108

5292

5400

600

6000

-P6

6000

260.31

260

0.12

6260.30

6260

0.005

P10

50 001.26

50002.69

0.003

P11

50 001.26

50002.69

0.003

P12

50 000

P13

50 000

P14

6259.04

6257.31

0.028

Cool In

50 000

Hot Out

50 000

Product

1.26

Water

55 581.85

141

Table 2.6: Summary of Molar Flow Rate for Each Stream

Stream

Molar Flow Rate

Differences

(kmol/day)

(%)

Manual calculation

Simulation output

3.55

294

293.67

0.11

297.55

297.22

0.11

3.703

3.6

2.78

301.25

300.82

0.14

301.25

300.82

0.14

-P6

300.82

13.12

13.09

0.23

314.62

313.91

0.22

P10

2777.78

2774.78

0.108

P11

2777.78

2774.78

0.108

P12

2777.78

P13

2777.78

2774.69

0.11

P14

314.36

313.93

0.21

Cool In

2774.69

Hot Out

2774.69

Product

0.68

Water

3084.45

2.2.3

Manual Calculation for Energy Balance 142

Calculation for energy balances are important to determine the energy requirements of the process including the heating, cooling and power required in the process design. The energy balances of the process are calculated using shortcut methods in Systematic Methods of Chemical Process Design (Biegler and Grossmann, 1997).

Several assumptions have be made in dealing with energy balance such as:-



Ideal properties are used for evaluating the energy balance of the process streams.



Kinetics and potential energies are neglected for these streams, and considers only enthalpy changers.



As the standard reference state for enthalpy, where H = 0, Po = 1atm, To = 298.15 K, elemental species is considered.



Assume no H of mixing effect on H.



Steady-state condition in all equipment



References temperature for all calculation = 25 °C



Energy out = Energy in + Generation – Consumption + Accumulation, therefore the equation becomes, Q = ∆H = ∑ṁĤin - ∑ṁĤout

143

2.2.3.1 Autoclave

Reference state: T= 25°C, P =1 atm P = 15 bar Tstream in

out

25°C

121°C

Component

Mass flow

(kJ/kg.K)

rate, ṁ (kg/day) in

out

C6.014H10.03O5

600

1.396

H2SO4

1.42

H2O

5346

4.184

144

2.2.3.2 Incubator

Calculation of heat of neutralization:

H2 + S + 2O2

∆ Hf = -909.2

H2SO4 (l)

Na + O2 + H2

∆ Hf = -469.4

NaOH (l)

2Na + S + 2O2

∆ Hf = -1387.0

Na2SO4 (s)

H2 + O2

∆ Hf = -285.8

H2O (l)

H2SO4 (l) + 2NaOH (l)

Na2SO4 (s) + 2H20 (l)

Therefore, ∆ Hr = -1(-909.2

) -2(- 469.4

= -110.6

) +1(-1387.0

) +2(-285.8

)

(reaction is exothermic)

Reference state: T= 25°C, P = 1 atm) Tstream in

out

25°C

55°C

145

Component

Mass flow rate, ṁin

Qin (kJ/day)

Mass flow

Qout (kJ/day)

rate, ṁout

(kJ/kg.K)

(kg/day)

C6.014H10.03O5

600

1.396

25 128

600

25 128

H2SO4

1.42

2300.4

H2O

5562.27

4.184

698 176.13

5582.10

700 665.19

NaOH

44.043

0.706

932.83

Na2SO4

0.831

78.204

1 949.63

Inlet: Q C6.014H10.03O5 (s) =

Q H2SO4 (l) =

= 25 128

= 2300.4

Q H2O (l) =

= 698 176.13

Q NaOH (l) =

= 932.83

Outlet: Q C6.014H10.03O5 (s) =

Q H2O (l) =

= 25 128

= 700 665.19

146

Q Na2SO4 (s) =

= 1 949.63

∆ Q = Q out - Qin = 727 742.82

–726 537.36

= 1205.46

2.2.3.3 Extraction Unit

Ref: (substance - C7.48H12.52O4.16 (s); Na2SO4 (s); H2O (l), 25°C, 1 atm Tstream in

out

55°C

327°C

Component

Mass flow rate, ṁin

Qin (kJ/day)

Mass flow

Qout (kJ/day)

rate, ṁout

(kJ/kg.K)

(kg/day)

C6.014H10.03O5

600

1.396

25 128

H2O (l)

5582.10

4.184

700 665.19

5582.10

700 665.19

Na2SO4

78.204

0.831

1 949.63

78.204

19 626.23

C6H10O5

1.395

598.74

252 243.17

C15H24O (v)

2.895

0.072

62.95

C15H26O (v)

3.032

0.696

637.30

C10H16O (v)

2.849

0.492

423.32

H2O (v)

147

Calculation Cp ∆T for H2O (v):

Ĥout 25°C H2O (l)

327°C H2O (v) Ĥv

100°C H2O (l)

100°C H2O (v)

Cp ∆T = 4.184

(100 - 25) °C + ∆Ĥv + 2.051

= 313.8

+ 2445.2

(327 – 100) °C

+ 457.41

= 3216.41

Inlet: Q C6.014H10.03O5 (s) =

Q Na2SO4 (s) =

Q H2O (l) =

= 25 128

= 1 949.63

= 700 665.19

148

Outlet: Q Na2SO4 (s) =

= 19 626.23

Q C6H10O5 =

= 252 243.17

Q C15H24O (v) =

= 62.95

Q C15H26O (v) =

= 637.30

Q C10H16O (v) =

= 423.32

Q H2O (v) =

= 160 820 500

Q H2O (l) =

= 700 665.19

Q for distillation unit: ∆ Ħ = ξ Ĥ°r + ∑ ńout Ĥout - ∑ ńin Ĥin ∆ Qin = 25 128

+ 1 949.63

+ 700 665.19

= 727 742.82 ∆ Q out = 19 626.23

+ 252 243.17

+ 160 820 500

+ 62.95

+ 637.30

+ 423.32

+ 700 665.19

= 973 658.10 149

∆ Q = Q out - Qin = 161 794 158.1

- 727 742.82

= 245 915.28

Q steam = - Q distillation unit Therefore, 245 915.28

of heat is needed to supply from boiler to the distillation unit.

Q steam = - 245 915.28

Assuming the flow rate of steam = 50 000

Estimating Cp = 2.113

- 245 915.28

= 50 000

(2.113

) (327 - Tin) °C

Tin = 329°C

2.2.3.4 Boiler

Assume operating pressure is 0.3MPa

150

Based on Table B.7 Properties of Superheated Steam, When superheated water at 492.64°C and 0.3MPa, using extrapolation method,

Ĥ = 3128.95 Q = ṁ ∆Ĥ = ṁ (Ĥout – Ĥin) Q = ṁ [Ĥout – Cp (Tin - Tref)] Q = 50 000

[(3128.95

) – 4.184

(25 - 25)]°C

Q = 156 447 500

2.2.3.5 Condenser Calculation for C15H24O (l): 327 °C C15H24O (v) Q1

∆ Ĥcondensation 113.28°C C15H24O (v)

113.28°C C15H24O (l)

+ ∆ Ĥcondensation Q1

151

Calculation for C15H24O (l):

327 °C C15H26O (v) Q2

∆ Ĥcondensation 114.63°C C15H26O (v)

114.63°C C15H26O (l)

+ ∆ Ĥcondensation

Calculation for C10H16O (l):

327 °C C10H16O (v) Q3

∆ Ĥcondensation 137.56°C C10H16O (v)

137.56°C C10H16O (l)

152

+ ∆ Ĥcondensation Q3

Calculation for H2O (l):

327 °C H2O (v) Q4

∆ Ĥcondensation 100°C H2O (v)

100°C H2O (l)

+ ∆ Ĥcondensation

Q4 Q1 + Q2 + Q3 + Q4

153

Summary of Manual Calculation Enthalpy for Each Stream

Table 2.7

Summary Enthalpy for Each Stream

Enthalpy for Each Stream Stream

Enthalpy, H (kJ /day)

2 158 990.85

27 428.40

28 079.04

727 742.82

1123.57

11 12

156 447 500

972 524.59

154

Summary of Manual Calculation Heat Duty for Each Unit Operation

Table 2.4

Summary Heat Duty for Each Unit Operation

Heat Duty for Each Unit Operation Unit Operation

Heat Duty, Q (kJ /day)

Autoclave

2 158 990.85

Incubator

1205.46

Extraction Unit

245 915.28

Boiler

156 447 500

Condenser

-161 256 699.1

155

CHAPTER 3

PROCESS ENERGY INTEGRATION

3.1

Introduction

Energy consumption is a major part of any plant‟s operating cost. Mainly, energy is used as a heating and cooling utility.

The process of optimizing the

consumption of heating and cooling streams generated by the energy recovery is called “Process Heat Integration”. Process heat integration is a technique to match hot and cold streams in a plant to achieve heat transfer and reduce hot and cold utility consumption.

Energy recovery is the main objective for this design. For this purpose, heat exchanger network will be established. Before proceeding to design the heat exchanger network, heat exchanger area and the energy utilities consumption should be known to compare with the utility consumption after heat integration. These energy utilities

156

should be optimized in order to reduce the utilities consumption of the process, and thus reduce the operating cost of the plant.

The â&#x20AC;&#x153;Pinch Technology Methodâ&#x20AC;? will be used to determine the pinch temperature, minimum heating and cooling requirements of the plant. This will be followed by the maximum energy recovery (MER) design, to design the above pinch and below pinch regions of the heat exchanger network. Finally, the heat exchanger area and its utility consumption will be determined and comparisons of the utility consumption before and after heat integration will be made.

3.2

Stream Data Extraction

The stream data extraction was done based on our process flow diagram. The hot and cold streams obtained from the inlet and outlets of the heat exchangers were identified for heat integration. Table 3.1 low shows the summary of hot streams and cold streams extracted from the plant with all the parameters involved.

157

Table 3.1: Summary of Hot and Cold Streams from Simulated Results Stream Type

Stream Ts(oC)

Tt (oC ΔT(oC)

FCp(k

)

W/oC)

ΔH(kW)

Hot

121

0.2695

17.7848

Hot

327

100

237

1.1170

264.7367

Cold

121

0.2603

24.9883

Note: Ts = Supply Temperature; Tt = Targeted Temperature

H = FCpT

3.3

H

= Enthalpy Change (kW)

FCp

= eat Capacity Flow rate (kW/C)

T

= Temperature difference of supplied and targeted (C)

Pinch Technology

The amount of energy consumed can be determined from the process plant by using the “Pinch Technology Method”. The most common method to calculate the amount of energy recovered using the pinch technology are through plotting composite 158

curve or from the problem table algorithm. For our plant, the Problem Table Algorithm is used to calculate the energy recovery due to its accuracy compared with the composite curve method.

In pinch technology, the tradeoff between energy and capital in the composite curve studies suggest that on average, individual heat exchangers should have a temperature difference that is no smaller than Tmin. A good initialization for the heat exchanger network design is to assume that the temperature difference in an individual heat exchanger should not be smaller than Tmin between the composite curves.

With this in mind, the process is in a heat balance with minimum hot utility, QHmin. Above the pinch temperature, heat is received from the hot utilities and no heat is released. This process acts as a heat sink. Below the pinch temperature, the process is in heat balance with the minimum cold utility, QCmin. This process acts as a heat source. The Heat Cascade Table is used to determine the pinch temperature before proceeding to the Pinch Heat Recovery Design.

Basically, the steps that must be followed to determine the heat integration of the plant in using the Pinch Technology are as follows:

The hot and cold streams are determined.

ii.

The H, T and FCp are extracted from the simulation results.

iii.

Determine Tmin or assumed to 10˚C

iv.

Calculate the Ts shifted and Tt shifted, 159

For the hot streams, Ts shifted = Ts – ½ Tmin, For the cold streams, Tt shifted = Tt – ½ Tmin v.

The minimum heating requirements, QH,min, minimum cooling requirement, QC,min and pinch temperature, Tpinch are determined from the heat table cascade.

vi.

The pairing of streams are determined from the Maximum Energy Recovery (MER) method, For the above pinch region, CPc > CPH For the below pinch region, CPH > CPc

vii.

The utility consumption and area of every heat exchanger are calculated.

viii.

Summarize the overall integrated streams in the plant after maximum energy recovery (MER)

ix.

Comparison of utilities consumption and area before and after MER to determine the MER efficiency.

3.4

Problem Table Algorithm

Firstly, the Minimum Approach Temperature, Tmin must be determined for the energy recovery system of the plant. The best value of Tmin is very significant because Tmin will determine the size of the heat exchanger in a network. When the value of Tmin is decreased, the utility consumption and cost are also decreased, but the heat recovery, the size and capital cost of the equipment will be increased.

160

For our plant, Tmin of 10˚C is selected. This temperature is chosen not through economic analysis of the plant but according to practical constraints. With the set Tmin, shifted temperatures are then determined for each of our supply and target temperature. Table 3.2 shows the shifted temperatures for the hot and cold streams.

For Tmin = 10˚C, For hot stream, Tsupply (shifted), Tss,h = Ts -

1 (Tmin) 2

Ttarget (shifted), Tst,h = Tt -

1 (Tmin) 2

For cold stream, Tsupply (shifted), Tss,c = Ts +

1 (Tmin) 2

Ttarget (shifted), Tst,c = Tt +

1 (Tmin) 2

Table 3.2: Shifted Temperature for the Hot and Cold Streams in Pinch Technology

Stream Type

Ts (˚C ) Tt (˚C ) Tss (˚C ) Tts (˚C ) T(˚C ) FCp

ΔH(kW)

Hot

121

116

0.2695 17.7848

Hot

327

100

322

227

1.1170 264.7367

Cold

121

126

0.2603 24.9883

Note : Tmin = 10˚C 161

Tss = Shifted Supply Temperature; Tst = Shifted Targeted Temperature

Heat cascade calculation was performed and shown in Figure 3.1. The minimum heating requirement and Tpinch is then determined from the heat cascade.

Tit(˚C)

Stream Population

322

Tinterval

FCPc-

Hinterval

(˚C)

FCPH

(KW)

126

196

1.1170

218.932

0.8567

8.5670

1.1262

23.6502

0.0092

0.414

- 0.2603

- 5.206

116

Figure 3.1

Determinations of Heat Intervals, Hinterval

162

Q steam

Q steam = 0

T0 = 322 ºC ΔH1= 218.932 T1 = 126 ºC

R1 = 218.932

ΔH2= 8.5670 R2

T2 = 116ºC

R2 = 227.499

ΔH3= 23.6502

T3 = 95ºC

R3 = 251.1492

R4 = 251.5632

ΔH4= 0.414 T4 = 50ºC ΔH5= - 5.206 T5 = 30 ºC Q cw

Q cw = 246.3572

Figure 3.2: Heat Cascade

From the heat cascade table: i.

All values are positive (no largest negative point) and this is a Threshold Problem meaning either heating or cooling is required and not both.

ii.

The minimum cooling requirement, QC,min

= 246.3572kW.

iii.

The minimum heating requirement, QH,min

= 0.00 kW.

iv.

Since cooling is required, it is similar to a below pinch design. 163

Figure 3.3

Composite Curve

Figure 3.3 above shows the composite curve plotted. It is obvious that there is no pinch temperature. The current curves cannot be moved to a further right or left as we would not be able to achieve a minimum heat requirement. Thus, they will be exchanging less heat between them. We cannot cross the two curves as it will violate the temperature requirement set. The Tmin of 10˚C is just an assumption made for calculation purposes.

From the composite curve plotted, it is shown that there is no pinch temperature for our particular case. Since cold utilities are needed and hot utilities are not needed as shown in the graph, we therefore can conduct the heat integration similar to cases below pinch. Hence T from the composite curve plotted is 121˚C, which is the temperature difference of both the hot and cold stream plotted in the composite curve shown. 164

3.5

Maximum Energy Recovery (MER)

Maximum energy recovery is a part of our target to reduce the cost and amount of energy consumption.

Therefore, heat exchanger network design was done to

determine the requirement of energy needed.

Before that, the streams, which are

involved in the networking, are divided to the above pinch and below pinch based on pinch temperature (Problem Table Algorithm). In this case, the networking is done for below pinch temperature as shown in Figure 3.3.

FCp(kW/oC) â&#x2C6;&#x2020;H(kW)

T pinch H1 H2 C1

121

327

100 121

0.2695

17.7848

1.1170

264.7367

0.2603

25.8688

Figure 3.4: Stream Matching Below Pinch

3.6

Feasibility of Stream Matching

In the following section, the matching of streams is performed. Calculations involved in determining the feasibility of heat transfer is shown below.

165

327˚C T1 T

100 ˚C T2 25 ˚C

Figure 3.5

Matching of Stream 3 with 10

Heat needed for heating stream 4 from the supplied temperature to the desired temperature is calculated as shown below: Since heat transfer occurs (assume no heat losses), therefore;

ΔH  FCp ΔT 264.7367 kW = 1.1170 kW/˚C (T – 25) = 262˚C

Therefore, T1 = (327 – 262.0069) ˚C = 65 ˚C and

T2 = ( 100 – 25 ) ˚C = 75 ˚C

Since the T1 and T2 of the heat exchanger are larger than T (i.e.> 10˚C), therefore, the exchanger is feasible.

166

From the above pinch design, heat utilities required are: Stream 5:QC

= FCp,2T

= 0.2695 (121 – 55) kW

= 17.787 kW

= FCp,11T

= 1.1170 (262 – 100) kW

= 180.954 kW

Stream 10: -

3.7

Comparison of Energy Consumption Before and After Heat Integration

Table 3.3: Comparison between the Energy Consumption Before And After Heat Integration Energy Consumption (kW) Stream

Before Integration

After Integration

17.7848

264.7367

282.5215

198.7388

24.9883

180.954

167

From Table 3.3;

Cold utilities consumption before MER

= 282.5215kW

Cold utilities consumption after MER

= 198.7388kW

Total saving

282.5215  198.7388 100 282.5215

= 29.66%

Hot utilities consumption before MER

= 24.9883 kW

Hot utilities consumption after MER

= 0 kW

Total saving

24.9883  0 100 24.9883

= 100.0%

168

3.8

Conclusion

After the heat integration, the consumptions of utility are almost the same as the one before heat integration. The comparison between the utility consumptions before and after maximum energy recovery (MER) is concluded that there are a total of 2 cooling utilities and 1 heating utility as the energy saving percentages from the heat integration are much lower than expected. This is due to the less streams that are intensively in need of heating and cooling. At most, we are able to save 100.0% of energy for heater utilities and 29.66% of energy for cooling utility. The integrated network has successfully increased the efficiency of the plant in the aspect of energy utilization.

169

HOT OUT SP 10 SP-1 P-1 / V-101

SP-3

S-103 SP-6 P-4 / HX-101

Blending / Storage P-10 / HX-103

Cooling

Heat Exchanging GAHARU

P-8 / HX-102 P-5 / PM-101

Heat Exchanging

Fluid Flow SP 6

SP-11

SP-5 SP-4

PRODUCT

COOL IN

SP 13 P-2 / V-102

WATER P-9 / V-105

Vessel Procedure

Decanting

P-3 / GR-101 Grinding

P-6 / V-103 SP-8

SP-9 SP-10

Blending / Storage

SP-14 P-7 / V-104 Batch Distillation

Figure 3.6: Process Flow Diagram after Energy Integration

170

CHAPTER 4

WASTE MANAGEMENT

4.1

Introduction

Waste management is the important part other than processing and balancing of mass and energy because managing waste also can be used to cover the production cost. Besides, the most important is the wastes produced do not give bad effects to environment. The waste treatment strategy has to meet the regulation of Environmental Quality Act 1974 (amended 1996) Malaysia and the international standard ISO 14001. Disposal of hazardous waste on-site or off-site is governed by DOE (Department of Environment, Malaysia) regulations on scheduled waste. The quality of discharge should comply with the Scheduled Waste Regulations 1989.

The gaharu extraction plant does not involve many chemicals. So, the waste treatments for hazardous material do not take into consideration in this plant. However, the waste still need to be managed properly. Firstly, we have to consider the economic aspect, whether the waste can be recover and sell as a product or not. Commonly, there are two approaches to deal with waste produced from an industry. There are

171

1. Waste minimization 2. End-of-pipe Treatment

Waste minimization is to eliminate or reduce the waste generated at the source or by not producing it in the first place. Hence, it will eliminate any problems in treating it and at the same time we can save more on capital cost. On the other hand, end-of-pipe treatment means to transform the generated waste into another kind of harmless materials so that it can be released to the environment by using any physical, chemical, and biological or the combination of three methods. In thisGaharu oil extraction plant, almost of the waste produced can be further processing to produce byproduct or sell to other parties.

4.2

Guidelines for Environment Protection (ISO 14001-Environment Management System)

Nowadays, the environmental concern has increased and many company or individual know about the environmental issues. They try to control their activity impacts, products or services that will affect the environment. The international standard ISO 14001 specifies the requirements of such an environmental management system. It has been written to be applicable to all type and sizes of organizations and to accommodate diverse geographical, cultural and social conditions.

172

The implementation of environmental management techniques in a systematic manner can help to increase the interest customer number. This is because it defines that the company that got certification ISO 14001:

a) is appropriate to the nature, scale and environmental impacts of its activities, products or services b) includes a commitment to continual improvement and prevention of pollution c) includes a commitment to comply with relevant environmental legislation and regulations, and with other requirements to with the organization subscribes d) provides the framework for settling and reviewing environmental objectives and targets e) is documented, implemented and maintained and communicated to all employees, and f) is available to the public.

4.3

Sources of Waste

The wastes from Gaharu essential oil extraction plant produced after pretreatment and processing. The equipments that produce waste when processing are as follows:

173

Table 4.1 Types of Equipment That Produce Waste. Equipment

Waste produced

Distillation still

Gaharupulp sodium sulphate salt

Autoclave Incubator

Waste Waste produced in operations such as start-up and shutdown of continuous processes,

Distillation still Condenser

product changeover, equipment cleaning for maintenance, tank filling, etc.

Cooler Heater Oil water separator

From the table above, it is shown that there are two types of waste, the solid waste and waste water. The solid waste is gaharu pulp that has high economic potential to be sold as whole or turns into useful products.

The waste water contains sulphuric acid, sodium sulphate, enzyme residue and etc which make the effluent turbid and can not be discharge directly. The waste water produced is at low pH as excess sulphuric acid which is partially neutralized by sodium hydroxide during pretreatment is discharged. However, the waste water is at appropriate temperature to be discharge and there is no need to cool down before discharge. The water vapor outlet from distillation still passes through a condenser which condensed the vapor into water. After that, then waste water is being separated via oil water separator and hence the water cools down to lower temperature along the way which is safe to be 174

discharge and do not cause harm to aquatic life. As the result, the waste water needs to be treated before discharge.

4.4

Waste Management

4.4.1

Solid Waste Management

The Gaharu wood pulp after Gaharuoil is extracted from the wood can be utilized and turn into useful products like Gaharu pellets, perfume, soap, lotion, cream, candle, beads for religious purposes or else can be sold to other parties.

Gaharu has more benefits and usage, it use for enhance more aromatic scent in perfume and fragrance industry, use for medical purpose to healing and treatment in some problems, for beauty products as a good combination. Use for religious and spriritual purpose or even use for personal collection. See more information of Gaharu knowledge and its benefits.

4.4.1.1 GaharuPellets

175

Gaharu Pellets is developed from gaharu pulp after gaharu oil is extracted from the wood. The gaharu waste wood used in this new product is the light cream/brown powdery wood obtained after gaharu oil extraction. It still contains little resin content. These pellets can be used as an affordable aromatherapy substituting expensive gaharu chips when burnt. It can function as a deodorizer with addition of essential oils or fragrances during the manufacturing process.

The larger the diameter of the gaharu pellets, the longer is the time to enjoy the aroma of the exquisite essential oils. By using this innovative gaharu pellet product, the aroma of essential oils can be detected fast, at higher intensity than other products from ordinary heated equipment. The products are harmless and safe for the consumers as no chemicals are used. These value-added products may have a niche in aromatherapy and healthcare industry.

Two types of products were already developed aregaharu pellets for aromatherapy which is affordable gaharu aromatherapy and easy to use, need no heating device or appliances; and the deodorizer with exquisite essential oils where gaharu pellet is naturally blended with essential oils or fragrances has the ability to get rid unwanted smell and also suitable to place in cupboards, wardrobes, shoes cupboards, cars, kitchens and animal cages. It can retain well the scent of essential oils/ fragrances and can be used again after 3 months with added new fragrances.

176

Figure 4.1: Gaharu pellet

4.4.1.2 GaharuJoss Stick

The gaharu pulp can be turn into joss stick where it is blend with mix with binder to form a paste, which, for direct burning incense, are then cut and dried into pellets.

Joss sticks are the name given to incense sticks used for a variety of purposes associated with ritual and religious devotion in China and India.Joss-stick burning is an everyday practice in traditional Chinese religion. There are many different types of joss sticks used for different purposes or on different festive days. Many of them are long and thin and are mostly colored yellow, red, and more rarely, black. Thick joss sticks are used for special ceremonies, such as funerals. Spiral joss sticks are also used on a regular basis, which are found hanging above temple ceilings, with burn times that are exceedingly long. In some states, such as Taiwan, Singapore, or Malaysia, where they 177

celebrate the Ghost Festival, large, pillar-like dragon joss sticks are sometimes used. These generate such a massive amount of smoke and heat that they are only ever burned outside.

Figure 4.2: Giant Dragon Joss Stick

Figure 4.3: The Spiral Joss Stick 178

4.4.2

Waste Water Treatment

4.4.2.1 Screening of Alternative Waste Treatment Processes

There are numerous methods to treat the organic contaminants in the liquid or gaseous wastes. Most of the treatments available are not particular in nature; mean that it can also be used to treat any other organic material other than the proposed one.

The treatment process currently in use in the industry includes a wide range of choice, either physical method, chemical or biological. Although these categories involve numerous methods, but they do tend to have a general criteria. The basic descriptions for each of these categories are listed as follows.

(i) Physical Process

Types of physical process include distillation, evaporation, steam stripping, air stripping, liquid extraction carbon adsorption and resin adsorption. The main advantages of physical process in general are the cost and the simplicity of its design. The ease of maintenance also is a very attractive factor. The disadvantages, is it is not very effective for the treatment of highly contaminated wastewater. Furthermore most of the process tends to produce high volume of residual, which had to be treated by incineration (extra cost). Anyhow, incineration can be used for direct ultimate disposal of the waste on its own individual operation without other pre-treatment physical instruments.

179

(ii) Chemical Method

Chemical treatment in general is based on the principle of oxidizing the organic compound in the wastewater using oxidant chemical to fundamental product of oxidation such as carbon dioxide and water. Little type of chemical treatment processes is wet air oxidation, supercritical water oxidation, ozonolysis and chlorinolysis. These methods are only efficient for specific process especially inorganic contaminant. Furthermore the usage of chemical may produce unwanted and maybe dangerous product if the wastewater contains certain unpredicted compound that may react with the chemical used. Although this seldom happens, but the possibilities is their and any assurance of this will cause a very big problem. Furthermore these chemicals are quite costly and less cost efficient compared to the physical methods.

(iii)Biological Method

This is the most popular method for plants that are producing heavy stream of wastewater with a highly contaminant of organic. Biological treatment process used for the removal of organic solvents and other VOCs from industrial waste stream can be divided into two major categories as follows:

a) Aerobic process b) Anaerobic processes

In aerobic system microorganism use oxygen to biologically oxidize compounds. Anaerobic systems do not require oxygen and these anaerobic exist and react in a relatively free environment. Although there are numerous methods for biological treatment where each will give a good and efficient treatment, biological method in general involves a very high cost and usage of wide spaces, which can be very limiting 180

in our circumstances. There are biological technologies that are space saving but there are either costly or not suitable for heavy flow of wastewater.

4.4.2.2

Selection of Process

Based on the discussion of the three categories of treatment process, it is very clear that the biological processes will be very suitable treatment for our circumstances. For the liquid wastes we choose activated sludge treatment system. Although this may not be a cost-wise decision but we can assure it is very effective for organic waste treatment whilst the waste discharge will be more environmental friendly

4.4.2.3

Process Description

The process involved in wastewater treatment plant is biological treatment with activated sludge system. The waste from all streams will be fed into an equalizer tank. The equalizers tank not a treatment process but a technique to improve the effectiveness of secondary and advanced wastewater treatment.

Wastewater is pumped into the aeration tank, where either air from atmosphere is bubbled into the tank or the mechanical surface aerator is used to saturate the wastewater with oxygen. Microorganisms exist in the aeration tank to digest the organic waste, such as ethylene, benzene. 181

The biological treatment of wastewater stream is based on the ability of a mixed population of microorganisms to utilize organic contaminants as nutrients. Organic constituents are removed by aerobically converting them to carbon dioxide and water (mineralization), or bio-transferring to less toxic or non-toxic organic compounds.

The microorganism population in the biological treatment process can either be natural or developed to act on specific compounds in the waste. Both procaryotic and eucaryotic organisms have potential for biological treatment of toxic organic.

ď&#x201A;ˇ

Eucaryotic, which includes protozoa, fungi and most groups of algae, has highly organized cell structure.

ď&#x201A;ˇ

Procaryotic, which includes bacteria and blue-green algae, has a much simpler cell structure without a classical nucleus.

Because biological systems contain living organism, they require specific ratios of carbon and nutrients. The most important nutrients are nitrogen, phosphorus, sulphur, potassium, calcium, and magnesium. Since, we assume that nitrogen exists in the wastewater, there is no additional nutrient is needed. Water is also a necessary component of all living organisms and therefore is a vital part of the biological waste treatment systems. Industrial wastewater often lacks of the essential macro and micronutrients, which must therefore be added during treatment.

The outlet stream from aeration tank W2 is then being pump into a clarifier. Here, the microorganisms and suspended particles are given enough time to settle down. Mixing it with the inlet stream before entering aeration tank will recycle the sludge. Prior mixing, the sludge will be pressed by filter press to separate solid from liquid. The solid will be sent to KualitiAlam for disposal. The liquid then will recycle. 182

The effluent from clarifier W3 will be nearly pure water and is safe to discharge into drainage system.

Influent

S,X

Qo,So,Xo

Equalizer

Se,Xe

Qo+ Qr

Qu- Qw

Clarifier

Aeration

Figure with Activated Sludge System Tank 4.1 :Biological Treatment Tank Pump 1,W1

Pump 4 Pump 2,W2

Qu,Xw

Qr,Xw

Filter press

Qw,,Xw,Sw

Pump 3,W5

Figure 4.4 : Biological Treatment with Activated Sludge System

4.4.2.4 Material Balance for Waste Treatment Plant

Design parameters and assumption are listed as follow (Tchobanoglous, 2003):

= flow rate to aeration tank

= 24.9122 m3/d

= biomass concentration in aeration tank

= 2000 mg/L

= concentration of sludge wasted daily

= 10 kg/m3

= Influent BOD5

= 1000 mg/L

= Required effluent BOD5

= 20 mg/L

c

= Mean cell residence time

= 10 days

= decay coefficient

= 0.06 day-1

= yield coefficient

= 0.6 g VSS/g COD 183

The following conditions are applicable to design a complete-mix activated sludge system.

-Influent volatile suspended solids to aeration tank are negligible. -Return sludge concentrations = 10 000 mg/L -Suspended solids in the effluent = 0 mg/L

Volume of aeration tank, V =

 c Q o Y So  S X 1  K d c

45.7761 m3

Hydraulic retention time, =

V Qo

1.8375day

44.1hours

Volume of sludge wasted daily,Qw =

VX qXw

0.91552158m3/d

Mass of sludge wasted daily,QwXw =

9.15521576kg/d

0.38146732kg/h 184

Biological solid balance on clarifier, (Qo + Qr) X = (Qo – Qw)Xe + QuXw = (Qo – Qw)Xe + (Qr + Qw)Xw Set that Xe = 0. Then, =

QoX - QwXw (Xw- X) 5.083635963m3/d

Ratio for feed to recycle, =

Qr Qo

0.2040625

20.40625 %

Water discharge out from clarifier, Qo- Qw

23.9966302 m3/d

Balance around clarifier, QuXw

(Qo + Qr)X

59.9915754

5.99915754 m3/d

Food-to-mass ratio, F

QoSo VX

0.27210884 d-1 185

Observed yield, Yobs

Y 1 + kdqc

0.375

g/g

The net waste activated sludge produced each day, Px

YobsQ(So - S) x 1000 g/kg-1

9.1552 kg/d Vss

Oxygen requirement, O2

Q(S - So )

- 1.42Px

1000 g/kg =

11.41350232

Kg/day

Air Requirements,

- Compute the volume of air required, assuming that the oxygen-transfer efficiency for the aeration equipment to be used is 8%. A safety factor of 2 should be used to determine the actual design volume for the sizing the blowers.

Theoretical air requirement, assuming that air contains 23.2% O2 by weight.

ii)

Density of air at 1atm, 25oC = 1.185 g/L Airtheoy = 0.2428 kg/day / 1.185 g/l (0.232) = 41.5152 m3/d

iii)

Actual air requirement at 8% transfer efficiency, Airactual = 41.5152 m3/d / 0.08 = 518.9465 m3/d 186

4.4.2.5 Kinetics of Bacterial Growth

Bacteria

Organic matter +N H3 + O2 For first order equation,

C5H7NO2 + CO2 + NH3 + New biomass

dX  X dt

where,

dX  Growth rate of biomass mg/L/day dt X = concentration of biomass mg / L  = Specific growth rate constant, d -1 Notes: requirement for microbial growth, including availability of substrate. Limiting substrate concentration:

  m S m

S 20 5  1.25d 1 Ks  S 60  20

= concentration of limiting substance = 20 mg/L = maximum growth rate d-1 = 5 d-1

Ks = half – saturation constant = 60 mg/L BOD5 Growth rate for bacteria, X = X0 exp.(t) = 10 exp. (1.25x10) = 2683372.9 g/ L/day

4.4.2.6 Sizing and Costing of Waste Treatment Equipment

187

Equalization Tank:

Volume of wastewater

24.9122 m3/day

Setting space time

1 day

Tank volume require

24.9122 m3

Assume a cylindrical tank establish, which has L/D

R2L =

D3

(24.9122/)3

2.52 m = 8.27 ft

10.8 m = 35.43 ft

So,

Tank Diameter, D

Tank length, L

(D/2)24D

Since D 1.2 m, horizontal tank used.

The equalizer tank will be constructed establishing in storage tank, which is made from cast iron, the structure of the tank will be strengthen by pilling work. For the costing, equalization tank will assume as cylindrical storage tank with horizontal fabrication.

Escalate price using CE Plant Cost Index for 2003

CEI2003

405.6

CEI1968

115 CE03

CEI68

=3.5270

188

Base cost for pressure vessel from Table 4.11, page 134, (Biegler, 1997) For cylindrical tank, the general form of the cost given by BC

Co*(L/Lo)*(D/Do)

USD 10205

3.18

According to Table 4.2, page 113 (Biegler, 1997) MPF

Material of construction BMC =

FmFp

Carbon steel

UF*BC*(MPF + MF - 1)

USD 114230.7

RM 434076.66

Aeration Tank:

Flow rate of wastewater

24.9122 m3/day

Setting space time, t

3 day

Tank volume require

74.7365 m3

Assume a cylindrical tank establish, which has L/D

R2L =

D3

(74.7365/)3

2.88 m = 9.45 ft

11.52 m = 37.8 ft

So,

Tank Diameter, D

Tank length, L

(D/2)24D

Since D 1.2 m, horizontal aeration tank used.

189

Escalate price using CE Plant Cost Index for 2003

CEI2003

405.6

CEI1968

115 CE03

CEI68

3.5270

Base cost for pressure vessel from Table 4.11, page 134 (Biegler, 1997) For cylindrical tank, the general form of the cost given by BC

Co*(L/Lo)*(D/Do)

USD 1512.868

3.18

According to Table 4.2, page 113.(Biegler, 1997) MPF

Material of construction BMC =

FmFp

Carbon steel

UF*BC(MPF + MF - 1)

USD 16967.91

RM 64478.045

Clarifier:

Assume clarifier is a pressure vessel

Flow rate of wastewater

24.9122 m3/day

Detention time, t

1 day

Tank volume require

24.9122 m3

190

Assume a cylindrical tank establish, which has L/D

R2L =

D3

(24.9122/)3

2.00 m

8.4 m

So,

Tank Diameter, D

Tank length, L

(D/2)24D

Since D 1.2 m, horizontal aeration tank used.

Escalate price using CE Plant Cost Index for 2003

CEI2003

405.6

CEI1968

115

CE03

CEI68

3.5270

Base cost for pressure vessel from Table 4.11, page 134, (Biegler, 1997) For cylindrical tank, the general form of the cost given by BC

Co*(L/Lo)*(D/Do)

827.2003

3.18

According to Table 4.2, page 113.(Biegler, 1997) MPF

Material of construction

FmFp

Carbon steel 191

BMC =

UF*BC(MPF + MF - 1)

$ 9277.649

RM 35255.0658

Pump 1 & 4:

Brake horsepower; Wb

(P2 - P1)/(pm)

1.2000E05 pa

1.0133E05 pa



8.7000E-04



995.29 kg/m3

p

0.5

m

0.9

0.03628 W

4.861E-05 hp

Design type of pump is centrifugal.

Escalate price using CE Plant Cost Index for 2003

CEI2003

405.6

CEI1968

115 CE03

CEI68

3.5270

Cast iron

Design pressure 1.5 bar Material of construction

According to Table 4.8, page 125.(Biegler, 1997) MPF

FmFp

1 192

Base cost for process equipment from Table 4.12, page 134. (Biegler, 1997) BC

Co(S/So)

48.7312

3.38

UF*BC(MPF + MF - 1)

$ 580.9306

RM 2207.5362

Update bare cost model BMC

Pump 2:

Brake horsepower; Wb

(P2 - P1)/(pm)

1.3000E05 pa

1.0133E05 pa



8.7000E-04



995.29 kg/m3

p

0.5

m

0.9

0.0557 W

7.4639E-05 hp

Design type of pump is centrifugal.

Escalate price using CE Plant Cost Index for 2003

CEI2003

405.6

CEI1968

115 CE03

CEI68

3.5270

193

Design pressure 1.5 bar

Material of construction

Cast iron

According to Table 4.8, page 125.(Biegler, 1997) MPF

FmFp

Base cost for process equipment from Table 4.12, page 134. (Biegler, 1997) BC

Co(S/So)

52.4166

3.38

UF*BC(MPF + MF - 1)

$ 624.864

RM 2374.4833

Update bare cost model BMC

Pump 3:

Brake horsepower; Wb

(P2 - P1)/(pm)

1.5000E05 pa

1.0133E05 pa



8.7000E-04



995.29 kg/m3

p

0.5

m

0.9

0.0946 W

1.2670-04 hp

Design type of pump is centrifugal.

Escalate price using CE Plant Cost Index for 2003

CEI2003

405.6

CEI1968

115 194

CE03

CEI68

3.5270

Cast iron

Design pressure 2.0 bar Material of construction

According to Table 4.8, page 125.(Biegler, 1997) MPF

FmFp

Base cost for process equipment from Table 4.12, page 134. (Biegler, 1997) BC

Co(S/So)ď Ą

57.3503

3.38

UF*BC(MPF + MF - 1)

$ 683.6785

RM 2597.9785

Update bare cost model BMC

Filter Press:

Flow rate

0.2212 m3/s

1 unit cost $ 15000. The range between 0.1 - 1 m3/s

BMC = =

$ 15000 RM57000

195

Table 4.2 : Summary of Equipment Sizing in Wastewater Treatment Plant

Equipment

Volume (m3)

Power (kW) x10-3

Equalization tank

49.8243

Aeration tank

74.7365

Clarifier

24.9122

Pump 1

0.0363

Pump 2

0.0557

Pump 3

0.0946

Pump 4

0.0363

Table 4.3 : Summary of Equipment Costing in Wastewater Treatment Plant

Equipment

Total price (RM)

Pump 1

2207.53

Pump 2

2374.48

Pump 3

2597.98

Pump 4

2207.54

Clarifier

35255.07

Filter Press

57000.00

Aeration tank

64478.05

Equalization tank

434076.66

Total

600, 197. 31

196

Table 4.4 : Summary Sheet of Wastewater Treatment Plant

SUMMARY SHEET Identification : Wastewater Treatment Plant using activated sludge system Function

: Bio-oxidized organic waste from plant effluent Specification

Data

Design type

Activated sludge system

BOD5 inlet

1000 mg/L

BOD5 outlet

20 mg/L

Volumetric flow rate of inlet feed Operational Parameter Mean cell residence time, ď ą c

24.92 m3/d Data 10 days

Order of reaction

First order

Mixed liquor suspended solids, MLSS

2000 mg/L

Mixed liquor volatile suspend solids, MLVSS Residence time

1500 mg/L (75% of MLSS) 45 hr.

Recycle ratio (Recycle stream volumetric flowrate/Influent volumetric flowrate) Mass of Sludge produced Aeration Tank Volume

20 % 0.92 kg/day Data 74.75 m3

Mixed liquor depth at operating condition

6.0 m

Length of tank

11.2 m

Clarifier to separate solid and liquid

Data

Tank diameter

2.0 m

Length of Tank

8.4 m

Air Requirement in aeration tank Volume/day Oxygen transfer efficiency

Data 41.55 kg/day 8%

197

4.4.2.7 Costing for Sludge Disposal

Cost for sludge disposal

= RM 450/ tan (KualitiAlamSdn. Bhd.)

Total production of sludge

= 9.17 kg/day = 3026 kg/year

Total cost for disposal treatment

4.4

= RM 1361.75/year

Conclusion

Table 4.5 : Summary of Costing for Waste Treatment

Waste Water Treatment Plant in Gaharu Oil Extraction Plant Types

Total Price (RM)

Wastewater Treatment

600197

Annual Disposal Charge (KualitiAlamSdn.Bhd) Types

Total Charge (RM/year)

Sludge

1361

Total

601 558

The solid wastecan be turn into useful products like gaharu pellets, perfume, soap, lotion, cream, candle, beads for religious purposes or else can be sold to other parties. Hence, the costing for waste treatment do not includes treatment for solid waste.

198

The effluent from the gaharu essential oil extraction plant has generated various type of components, which can be divided into two major types; solid and liquid waste. Although these effluents have been treated thoroughly by using all types of pollution control devices, there are still traces of these components in the treated stream.

The effluent water will be discharged to the nearest river after it has been completely treated. The trace amount in this effluent can never be avoided, although we are not certain of what this amount will do to our nature, we just have to live with it. It is impossible to avoid waste in the chemical process. Perhaps, in the future we can build an environmental- friendly chemical plant.

We found the aerobic wastewater treatment is the most suitable to treat our wastewater. By using this method the organic constituents are removed by aerobically converting them to carbon dioxide and water (mineralization); or bio transferring to less toxic or non-toxic organic compounds. This treated wastewater can safely discharge to the environment according to the standard rules in Malaysia.

199

CHAPTER 5

EQUIPMENT SIZING AND COSTING

5.1

Introduction

Equipment sizing and costing is a crucial part in a plant design. It affects the profitability of a plant where the choice of material used and the size of the units determine feasibility of a plant. In this section, equipment sizing and costing will be conducted. The detail calculations of equipment sizing and costing are shown in the next sections. For this purpose, the calculations are based on the throughput into the equipment and its corresponding operating parameters. The results will be needed for the cost correlations to estimate the equipment cost.

5.2

Sizing and Costing

These are the types of equipment and the number of unit that need to calculate size and costing: 200

Equipment

5.2.1

Number of Unit

Grinder

Mixing Tank

Storage Tank

Autoclave

Incubator

Oil water separator

Extraction unit

Pump

Cooler

Condenser

Boiler

Sizing and Costing of Grinder

The grinder is used to grind bulk of gaharu raw material to being fine form. The size of fine gaharu needed is 5mm and the raw material used for every batch is 600 kg. Therefore the suitable size of grinder is important to make optimize process. The grinder consists of housing, shaft, rotor, bearing and screen area. Housing is the space of the grinder where shaft, rotor and bearing are the combination equipment to grind the gaharu wood. The screen area is to separate the desire size of gaharu and remove wood with oversizing. Three type of grinder that will be choosing consist of:

201

1. 15 Series Industrial Wood Grinder Model 15100

Company

Schutte Buffalo Hammer Mills Ltd

Motor Power

30 kW

Screw Speed

1800 rpm

Capacity

400 - 600 kg/hr

Rotor width

1220 mm

Shaft diameter

160 mm

Bearing

90 mm

Current `Price

RM 30,800

2. Recycling Wood Grinder Model CGT400-2

Company

Common Tech Ltd.

Motor Power

35 kW

Screw Speed

2000 rpm

Capacity

600 - 800 kg/hr

Rotor width

1320 mm

Shaft diameter

800 mm

Bearing

100 mm

Current `Price

RM 33, 000

202

3. MPG GP1220HB Granulator

Unlimited Resources Corp., Ltd.

Company Motor Power

45 kW

Screw Speed

2200 rpm 800 - 1000 kg/hr

Capacity Rotor width

1500 mm

Shaft diameter

950 mm

Bearing

120 mm RM 44, 8500

Current `Price

Conclusion

From three most suitable options stated above, it has been decided that the most suitable grinderis Recycling Wood Grinder Model CGT400-2 manufactured by Common Tech Ltd. because the capacity is in desired target. The price is relevant with the function where it can recycle the oversizing wood back to the initial process. Energy consumption also low but it can still provide enough capacity around 600 – 800 kg/hr of fine wood.

5.2.2

Sizing and Costing of Mixing Tank

Component

ḿin(kg/hr)

Ṽin(L/hr)

ḿout(kg/hr)

Ṽout(L/hr)

50 % H2SO4

108

77.419

1 % H2SO4

38.71

Water

5292

5346

5346 203

The working volume of the reactor = Total volumetric flow rate of outlet stream × Space time = (38.71 + 5346) L/hr× m3/1000L × (0.25hr) = 1.346 m3 Assume that, the working volume of the reactor = ⅔ of the storage volume of reactor. Thus, the volume of reactor = 1.346m3 (3/2) = 2.02 m3≈ 2 m3

The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 0.86 m

L = 4D = 4(0.86) = 3.44m (135 in; 11.3 ft)

The inside diameter of the vessel = 0.86 m (33.9 in; 2.82ft). Thus, the minimum wall thicknessshould be 0.0112 m (0.441 in; 0.0367 ft).

The type of agitator used in the reactor is turbine type. Since the reaction occurs involve homogeneous liquid reaction, the horsepower requirement for turbine type agitator is:

204

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL where, FM = material factor, CV = vessel cost and CPL = added cost for platforms andladders

For vertical vessel, Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (33.9 + 0.441)(135 + 0.8(33.9))(0.441×0.284) W = 2190.57 lb = 9.74 kN Cv = exp{7.0132 + 0.18255[ln 2190.57] + 0.02297[ln 2190.57]2} Cv = $ 17 614.77 CPL= 361.8 (Di) 0.73960(L) 0.70684 CPL= 361.8 (2.82) 0.73960 (11.3) 0.70684 CPL= $ 4 323.45 FM for carbon steel = 1.0 Thus, Cp = FMCv + CPL Cp = 1(17 614.77) + 4324.45 Cp = $ 21 938.22

The f.o.b purchase cost of turbine agitator can be calculated by equation; Cp = 3620 S 0.57

where S = horsepower

Cp = 3620(0.533)0.57 Cp = $ 2 528.97 205

The total purchase cost for the vessel: 21 938.22 + 2 528.97 = $ 24 467.19 Cp = (550/500)(24 467.19)

= $ 26 913.91 = RM 80 472.59

Table 5.1: Specification sheet for mixing tank, V-101

EQUIPMENT SPECIFICATION SHEET Identification : Mixing Tank Item No.

: V-101

Function

: Dilute 50% H2SO4 with water until to 1% H2SO4

Specification

Design Sizing

Design type Material construction

Vessel volume

2 m3

Vessel diameter

0.86 m

Vessel length

3.44 m

Turbine

Wall thickness

0.0112 m

80 rpm

Horse power (Hp)

0.533

Vertical of Stainless steel 316

Type of agitator Agitator speed Operating Condition

Equipment Estimated Cost

Residence time

15 min

BMC for tank (RM)

Operating temperature

25oC

BMC for agitator 7 561.62 (RM)

Operating pressure

1 atm

Updates BMC (RM)

65 595.28

80 472.59

206

5.2.3

Sizing and Costing of Storage Tank

Component

ḿout(kg/hr)

Ṽout(L/hr)

NaOH

260

240.18

The working volume of the reactor = Total volumetric flow rate of outlet stream × Space time = 240L/hr× m3/1000L × (0.25hr) = 0.06 m3 Assume that, the working volume of the reactor = ⅔ of the storage volume of reactor. Thus, the volume of reactor = 0.06 m3 (3/2) = 0.09 m3≈ 0.1 m3

The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 0.32 m

L = 4D = 4(0.32) = 1.27m (50 in; 4.17ft)

The inside diameter of the vessel = 0.32 m (12.6in; 1.05 ft). Thus, the minimum wall thicknessshould be 0.0042 m (0.165in; 0.0138ft). 207

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL where, FM = material factor, CV = vessel cost and CPL = added cost for platforms andladders

For vertical vessel, Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (12.6 + 0.165)(50 + 0.8(12.6))( 0.165×0.284) W = 112.9lb Cv = exp{7.0132 + 0.18255[ln112.9] + 0.02297[ln112.9]2} Cv = $ 4 399.2 CPL= 361.8 (Di) 0.73960(L) 0.70684 CPL= 361.8 (1.05) 0.73960 (4.17) 0.70684 CPL= $ 1 029.15 FM for carbon steel = 1.0 Thus, Cp = FMCv + CPL Cp = 1(4 399.2) + 1 029.15 Cp = $ 5 428.35

The total purchase cost for the vessel:

Cp = (550/500)(5 428.35)

= $ 5 971.18 = RM 17 853.83

208

Table 5.2: Specification sheet for storage tank, V-101

EQUIPMENT SPECIFICATION SHEET Identification : Storage Tank Function

: Store NaOH before supply to incubator

Specification

Design Sizing

Design type

Vertical

Vessel volume

0.1 m3

Material of construction

Stainless steel 316

Vessel diameter

0.32 m

Vessel length

1.27m

Wall thickness

0.0042 m

Operating Condition

Equipment Estimated Cost

Residence time

15 min

Operating temperature

25oC

Operating pressure

5.2.3

BMC for tank (RM)

17 853.83

1 atm

Sizing and Costing of Autoclave

Component

ḿin(kg/hr)

Ṽin(L/hr)

ḿout(kg/hr)

Ṽout(L/hr)

Gaharu

600

H2SO4

38.71

Water

5346

209

The working volume of the reactor = Total volumetric flow rate of outlet stream × Space time = (600 + 38.71 + 5346) L/hr × m3/1000L × (0.5 hr) = 2.992 m3

Assume that, the working volume of the reactor = ⅔ of the storage volume of reactor. Thus, the volume of reactor = 2.992 m3 (3/2) = 4.488 m3 ≈ 4.5 m3

The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 1.127 m

L = 4D = 4(1.127) = 4.508 m (177 in; 14.8ft)

The inside diameter of the vessel = 1.127 m (44.4 in; 3.7ft). Thus, the minimum wall thickness should be 0.0146 m (0.575 in; 0.0479ft).

The type of agitator used in the reactor is turbine type. Since the reaction occurs involve suspended of solid particles, the horsepower requirement for turbine type agitator is:

210

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL where, FM = material factor, CV = vessel cost and CPL = added cost for platforms and ladders

For vertical vessel, Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (44.4 + 0.575)(177 + 0.8(44.4))(0.575×0.284) W = 4903.51 lb = 21.8kN Cv = exp{7.0132 + 0.18255[ln4903.51] + 0.02297[ln4903.51]2} Cv = $ 27 533.08 CPL= 361.8 (Di) 0.73960 (L) 0.70684 CPL= 361.8 (3.7) 0.73960 (14.8) 0.70684 CPL= $ 6 395.85 FM for carbon steel = 1.0 Thus, Cp = FMCv + CPL Cp = 1(27 533.08) + 6395.85 Cp = $ 33 928.93

The f.o.b purchase cost of turbine agitator can be calculated by equation; Cp = 3620 S 0.57

where S = horsepower

Cp = 3620(7.904)0.57 Cp = $ 11 762

211

The f.o.b for fire heater can be calculated by equation:

= exp{0.32325 + 0.766[ln Q]} = exp{0.32325 + 0.766[ln 2158990.85]} = $ 98 270.19

The total purchase cost for the vessel:

33 928.93 + 11 762 + 98 270.19 = $ 143 961.12 Cp = (550/500)(143 961.12) = $ 158 357.23 = RM 473 488.12

Table 5.3: Specification sheet for autoclave, V-102 EQUIPMENT SPECIFICATION SHEET Identification : Autoclave Item No.

: V-102

Function

: Mix the solution and sterilize

Specification

Design Sizing

Design type Material construction

Vessel volume

4.5 m3

Vessel diameter

1.127 m

Vessel length

4.508 m

Turbine

Wall thickness

0.0146 m

68 rpm

Horse power (Hp)

7.904

Vertical of Stainless steel 316

Type of agitator Agitator speed Operating Condition

Equipment Estimated Cost

Residence time

30 min

BMC for tank (RM)

Operating temperature

121oC

BMC for agitator 35 168.38 (RM)

Operating pressure

14.8 atm

101 447.47

BMC for fire heater 293 827.87 (RM) Updates BMC (RM) 473 488.12

212

5.2.5

Sizing and Costing of Incubator

Component

ḿin(kg/hr)

Ṽin(L/hr)

ḿout(kg/hr)

Ṽout(L/hr)

Gaharu

600

H2SO4

38.71

Water

5346

5582

NaOH

44.043

23.019

Na2SO4

78.204

78.620

The working volume of the reactor = Total volumetric flow rate of outlet stream × Space time = (600 + 78.620 + 5582) L/hr × m3/1000L × (0.5 hr) = 3.130 m3 Assume that, the working volume of the reactor = ⅔ of the storage volume of reactor. Thus, the volume of reactor = 3.130m3 (3/2) = 4.695 m3 ≈ 5 m3

The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 1.168 m

L = 4D = 4(1.168) = 4.672 m (184 in; 15.3ft) 213

The inside diameter of the vessel = 1.168 m (46 in; 3.83ft). Thus, the minimum wall thickness should be 0.0152 m (0.598 in; 0.0499ft).

The type of agitator used in the reactor is turbine type. Since the reaction occurs involve suspended of solid particles, the horsepower requirement for turbine type agitator is:

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL where, FM = material factor, CV = vessel cost and CPL = added cost for platforms and ladders

For vertical vessel, Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (46 + 0.598)(184 + 0.8(46))(0.598×0.284) W = 5489.54 lb = 24.4kN Cv = exp{7.0132 + 0.18255[ln5489.54] + 0.02297[ln5489.54]2} Cv = $ 29 381.38 CPL= 361.8 (Di) 0.73960 (L) 0.70684 CPL= 361.8 (3.83) 0.73960 (15.3) 0.70684 CPL= $ 6 717.22 FM for carbon steel = 1.0

214

Thus, Cp = FMCv + CPL Cp = 1(29 381.38) + 6 717.22 Cp = $ 36 098.6

The f.o.b purchase cost of turbine agitator can be calculated by equation; Cp = 3620 S 0.57

where S = horsepower

Cp = 3620(8.269)0.57 Cp = $ 12 068.6

The total purchase cost for the vessel: 36 098.6 + 12 068.6 = $ 48167.2

Cp = (550/500)(48 167.2)

= $ 52 983.92 = RM 158 421.92 per unit

Three unit of incubator

= RM 158 421.92 Ă&#x2014; 3 = RM 475 265.76

215

Table 5.4: Specification sheet for incubator, V-103

EQUIPMENT SPECIFICATION SHEET Identification : Incubator Item No.

: V-103

Function

: Incubate mixture at constant temperature

Specification

Design Sizing

Design type

Vertical

Vessel volume

5 m3

Material of construction

Stainless steel 316

Vessel diameter

1.168 m

Vessel length

4.672 m

Turbine

Wall thickness

0.0152 m

50 rpm

Horse power (Hp)

8.269

Type of agitator Agitator speed Operating Condition

Equipment Estimated Cost

Residence time

30 min

BMC for tank (RM)

Operating temperature

55oC

BMC for agitator 108 255.33 (RM)

Operating pressure

5.2.6

1 atm

Updates (RM)

BMC

323 804.44.82

475 265.76

Sizing and Costing of Oil Water Separator

Component

ḿin(kg/hr)

Ṽin(L/hr)

ḿout(kg/hr)

Ṽout(L/hr)

C10H16O

0.492

C15H24O

0.072

C15H26O

0.696

Water

49998.74

216

The working volume of the reactor = Total volumetric flow rate of outlet stream × Space time = (50 000) L/hr × m3/1000L × (0.25 hr) = 12.5 m3 Assume that, the working volume of the reactor = ⅔ of the storage volume of reactor. Thus, the volume of reactor = 12.5 m3 (3/2) = 18.75 m3 ≈ 20 m3 The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 1.85 m

L = 4D = 4(1.85) = 7.4 m (291 in; 24.3ft)

The inside diameter of the vessel = 1.84 m (72.8 in; 6.07ft). Thus, the minimum wall thickness should be 0.0239 m (0.941 in; 0.0784ft).

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL where, FM = material factor, CV = vessel cost and CPL = added cost for platforms and ladders

For vertical vessel, Refer Chapter 8 – Mechanical Design 217

W = ( Di + ts)( L + 0.8 Di) ts ρ W = (72.8 + 0.941)(291 + 0.8(72.8))(0.941×0.284) W = 21 621.75 lb Cv = exp{7.0132 + 0.18255[ln21 621] + 0.02297[ln21 621]2} Cv = $ 67 763.62 CPL= 361.8 (Di) 0.73960 (L) 0.70684 CPL= 361.8 (6.07) 0.73960 (24.3) 0.70684 CPL= $ 13 095.34 FM for carbon steel = 1.0 Thus, Cp = FMCv + CPL Cp = 1(26 879.58) + 6 258.50 + 427.82 Cp = $ 33 565.9

(550/500)(33 565.9) = $ 36 922.49 = RM 110 398.25

218

Table 5.5: Specification sheet for oil water separator, V-105

EQUIPMENT SPECIFICATION SHEET Identification : Oil water separator Item No.

: V-104

Function

: Separate gaharu oil from water

Specification

Design Sizing

Design type

Horizontal

Material construction

of Stainless steel 316

Operating Condition 15 min

Operating temperature

25oC

5.2.7

12.5 m3

Vessel diameter

1.85 m

Vessel length

7.4 m

Wall thickness

0.0239 m

Equipment Estimated Cost

Residence time

Operating pressure

Vessel volume

Updates (RM)

BMC 110 398.25

1 atm

Sizing and Costing of Extraction Unit

Component

ḿin(kg/hr)

Ṽin(L/hr)

ḿout(kg/hr)

Ṽout(L/hr)

Gaharu

600

Water

5582.1

Na2SO4

78.204

78.620

219

The working volume of the reactor = Total volumetric flow rate of outlet stream × Space time = (5 660.62) L/hr × m3/1000L × (0.5 hr) = 2.830 m3 Assume that, the working volume of the reactor = ⅔ of the storage volume of reactor. Thus, the volume of reactor = 2.830 m3 (3/2) = 4.25 m3 ≈ 4.3 m3

The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 1.11 m

L = 4D = 4(1.11) = 4.44 m (175 in; 14.6ft)

The inside diameter of the vessel = 1.11 m (43.7 in; 3.64ft). Thus, the minimum wall thickness should be 0.0144 m (0.567 in; 0.0472ft).

Calculation for perforated grid inside the distillation unit

Area

= πD2/4

Assume width = 0.05 m

= π(1.11 – 2(0.0144))2/4 = 0.918 m2

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL 220

where, FM = material factor, CV = vessel cost and CPL = added cost for platforms and ladders

For vertical vessel, Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (43.7 + 0.567)(175 + 0.8(43.7))(0.567×0.284) W = 4 701.84 lb = 20.9kN Cv = exp{7.0132 + 0.18255[ln4 701.84] + 0.02297[ln4 701.84]2} Cv = $ 26 879.58

CPL for vessel CPL= 361.8 (Di) 0.73960 (L) 0.70684 CPL= 361.8 (3.64) 0.73960 (14.6) 0.70684 CPL= $ 6 258.50 CPL for perforated grid CPL= 361.8 (Di) 0.73960 (L) 0.70684 CPL= 361.8 (3.54) 0.73960 (0.164) 0.70684 CPL= $ 256.76 FM for carbon steel = 1.0 Thus, Cp = FMCv + CPL Cp = 1(26 879.58) + 6 258.50 + 256.76 Cp = $ 33 394.84

Cp = (550/500)(33 394.84)

= $ 36 734.32= RM 109 835. 63

221

Table 5.6: Specification sheet for extraction unit, V-104

EQUIPMENT SPECIFICATION SHEET Identification : Extraction unit Item No.

: V-104

Function

: Separate product from the mixture

Specification

Design Sizing

Design type

Vertical

Vessel volume

4.3 m3

Material of construction

Stainless steel 316

Vessel diameter

1.1 m

Vessel length

4.4 m

Wall thickness

0.0144 m

Filter area

0.918 m2

Filter width

0.05 m

Operating Condition

Equipment Estimated Cost

Residence time

30 min

BMC for tank (RM)

Operating temperature

327oC

BMC for perforated 767.71 grid (RM)

Operating pressure

5.2.8

Updates BMC (RM)

1 atm

99 082.86

109 835. 63

Sizing and Costing for Pump

The most commonly used type in the chemical process industry is the single stage, horizontal, overhung and centrifugal pump. Centrifugal pumps will normally be the first choice for pumping process fluids.

The other types only being used for special

222

application such as the use of reciprocating and gear pumps for metering. Pumps selection is made depending on the flow rate and head required, together with other process considerations. The single stage, horizontal, overhung, centrifugal pump is by far most commonly used type in chemical process industry. Other types are used where a high head or other special process considerations are specified. Pump selection is made on the flow rate and head required, together with other process considerations such as or the presence of solids in fluid.

The power required for pumping is given by: Power, P

PQ p

p

x100

Where, ΔP

= pressure differential across the pump, N/m2(Pa)

= flow rate, m3/s

p

= pump efficiency

To calculate the required differential head: i.

Determine differential pressure, ΔP

ii.

Determine head: Δh

P(2.31) SG

where,

iii.

ΔP

= differential pressure, psi

= specific gravity

Used 10% safety factor Required differential head = h + 10% safety factor

223

Volumetric flow, Qp =5.9847 m3/hr = 1.662 × 10-3m3/s = 26.4gpm

SG ΔP

=1 =2–1 = 1atm = 100 000 N/m2 = 14.5 psi

Differential head, Δh =

14.5.x 2.31 1

= 33.495ft = 10.2 m 10 % safety factor

= 10.2 x 0.1 =1.02 m

Required differential head, H = 10.2 + 1.02 = 11.4 m

From Figure 5.6 ( Sinnott, 1991) : For centrifugal pump, at capacity, Qp = 5.985 m3/hr and H = 11.4 m, single stage centrifugal pump

From Figure 10.62 ( Sinnott, 1991) : For centrifugal pump, at capacity, Qp =5.985 m3/hr and H = 11.4 m, Pump efficiency, p = 52 % Pump shaft power

PQ p

p

x100

100000 x5.985 x100 52

= 1.15096 x106 W = 1150.96 kW 224

W = 1150.96 kW = 1540hp

S = =

Qp H 0.5 26.4 33.50.5

= 4.561

CP = FTFMCB CB = exp {9.7171 -0.6019 [ln (S)] + 0.0519[ln (S)]2} = exp {9.7171 -0.6019 [ln (4.561)] + 0.0519[ln (4.561)]2} = 7 504.17

From Table 22.20, (Seideret al, pg 561) Qp = 26.4 gpm

H = 11.4

FT = 1 From table 22.21, (Seideret.al, pg 562) Assume, cast steel FM = 1.35 Purchase Cost = CP = FTFMCB = (1.5) ( 1.35) (7504.17) = $10 130.63 = RM 30 290.58

From table 22.11 ( Seider et. al, pg 549) FBM = 3.30

225

Bare Module Cost @ 550 = CBM = CP x FBM x

550 500

= $36 774.19 = RM 109 954.83

Table 5.7: Summary of Sizing and Costing for Pump, PM-101 EQUIPMENT SPECIFICATION SHEET Identification : Pump Item no

: PM-101

Function

: Increase pressure

Material of construction

Cast Steel

Type of pump

Single-stage centrifugal pump

Inlet flow rate

5.9847 m3/hr

Outlet flow rate

5.9847 m3/hr

Inlet pressure

1atm

Outlet pressure

2 atm

Inlet temperature

55o C

Outlet temperature

55o C

Differential head

10.2 m

Brake horse power

1540 hp

Purchased Cost

RM 30 290.58

Equipment Cost

RM 109 954.83

226

5.3.8

Sizing and Costing of Cooler

Heat exchanger sizing is done by estimating the condition of fluid that required to heat or to cool the stream. Few assumptions are made: 1. The overall heat transfer coefficient, U is constant. 2. The heat loss to surrounding is neglected. 3. Specific heat fluid remains constant. 4. Type of exchanger: 1-2 exchangers 5. Cooling water is used to cool the hot stream whereas steam is used to hot the cold stream.

Then, the difference of log mean temperature should be calculated:

Tlm 

(T1  t 2 )  (T2  t1 ) T t ln 1 2 T2  t1

R and S are then calculated, where

R

T1  T2 t 2  t1 ;

S

t 2  t1 T1  t1

Multiple the value of  Tlm calculated with FT(Figure 12.19 [1] ) to find the  Tm. Area of the heat exchanger can be found using the equation below: A

Q U Tm

The heat transfer between two fluids is generally done in heat exchanger. The most common heat exchanger available is one in which the hot and cold fluid do not come into direct contact with each other but are separated by tube and shell. There are generally three types of heat exchanger, which are Double-pipe heat exchanger, Shell and tube heat exchanger and Cross-flow heat exchanger.

227

In calculation of the heat exchanger, parameters that are important to be estimated such as area, tube site rating and shell side rating.

The hot stream needed to be cooled from 121°C to 55°C. Cooling water is used where the inlet temperature of cooling water is assumed as 25°C and the outlet is 30°C. From calculation, Q = -1 523 906 kJ/day. Assume heat capacity for cooling water as 4.2 kJ/kg K. Total rate of cooling water that required equal

m

Q 1day kg  K 1523906kJ 1 C   ( )( ) ( )  0.84 kg / s C p T day 86400s 4.2 kJ (30  25) C K

T1 = 121°C

T2 = 55°C

t1 = 25°C

t2 = 30°C

Tlm 

R

(121  30)  (55  25)  54.97 °C 121  30 ln 55  25

121  55  13.2 ; 30  25

S

30  25  0.052 121  25

By using Figure 18.14 When R = 13.2, S = 0.05 FT = 0.975   Tm = 0.975 (54.97ºC) = 13.798 ºC.

Based on Chem. Eng. Design Volume 6 Assumption: U = 300 W/m2.ºC

228

A

Q U Tm

17637.8 J m 2  K 1 A ( )( )  1.057 m 2 s 300 W 55.60 C

Using the methods in the Systematic Methods of Chemical Design, the cost for each of the heat exchanger can be estimated. These steps are:

With the calculated area, find the values of parameter that needed from table 4.12 (Systematic Methods of Chemical Design, pg

134). 2.

With the parameters determined, calculate the base cost for heat exchanger by applying the following equation, BC = Co(S/So)α

Refer to Table 4.4 for material and pressure factor to be used.

Then, cost of heat exchanger with updated bare module cost to figures out the values.

FBM

= 3.17

= exp{ 11.667 - 0.8709[ ln(11.4)] + 0.09005[ ln(11.4)]2} = 23 882.11

CBM

= 3.17(23 882.11)[550/500] = $ 83 276.92

= FPFMFLCB

229

Because pressure is not in the range, assume FP = 1 FM

= a + (A/100)b = 1.75 + (11.4/100)0.13 = 2.504

Assume, FL = 1 CP = 1(2.504)(23 882.11)(1) CP = $ 59 801.89 = RM 178 807.65 Table 5.8: Specification sheet for cooler, HX-101

EQUIPMENT SPECIFICATION SHEET Identification: Cooler Item no : HX-101 Function : To cool mixture solution Design Specification Type of heat Shell and tube exchanger (split ring floating head) 1 shell: 2 tube passes Material of Carbon steel construction Area of cooler 1.057 m2 Equipment Estimated Cost CBM (RM)

Tube Side Medium Inlet temperature Outlet temperature Shell side Medium Inlet temperature Outlet temperature

Mixture 121째C 55째C Cool Water 25째C 30째C

178 807.65

230

5.2.10 Sizing and Costing for Condenser

The hot stream needed to be cooled from 327°C to 25°C. Cooling water is used where the inlet temperature of cooling water is assumed as 20°C and the outlet is 86.19°C. Assume heat capacity for cooling water as 4.2 kJ/kg K. Total rate of cooling water that required equal

T1 = 327°C

T2 = 25°C

t1 = 20°C

t2 = 86.19°C

Tlm 

R

(327  86.19)  (25  20)  60.9 °C 327  86.29 ln 25  20

329  25  4.568 ; 86.19  20

S

86.19  20  0.216 327  20

By using Figure 18.14

When R = 4.568, S = 0.216 FT = 1   Tm = 1 (60.9ºC) = 60.9 ºC.

Based on Chem. Eng. Design Volume 6 Assumption: U = 10 Btu/hr.ft2.ºF = 56.784 W/m2.ºK

A

Q U Tm

231

A

161256699.1  10 3 J m2  K 1  0C  2 ( )( )   1.98 m 86400 s 56.784 W 60.90 C  273K 

FBM

= 3.17

= exp{ 11.667 - 0.8709[ ln(21.31)] + 0.09005[ ln(21.31)]2} = 18 873.26

= a + (A/100)b = 1.75 + (21.31/100)0.13 = 2.568

Assume FP = 1, FL = 1 CP

= FPFMFLCB

= 1(2.568) (1) (23 882.11)

= $ 48 465.20 = RM 144 910.95

232

Table 5.9: Specification sheet for condenser HX-102

EQUIPMENT SPECIFICATION SHEET Identification: Condenser Item no : HX-102 Function : Change vapor phase to liquid phase Design Specification Tube Side Type of heat Shell and tube Medium exchanger (split ring floating Inlet temperature head) Outlet temperature 1 shell: 2 tube Shell side passes Medium Material of Carbon steel Inlet temperature construction Outlet temperature 2 Area of cooler 1.98 m Equipment Estimated Cost CBM (RM) 144 910.95

Oil and steam 327°C 25°C Cool Water 20°C 86.19°C

5.2.11 Sizing and Costing of Boiler

Component

ḿin(kg/hr)

Ṽin(L/hr)

ḿout(kg/hr)

Ṽout(L/hr)

Water

50 000

Steam

50 000

= 18.75 m3 ≈ 20 m3

The volume of reactor can be also calculated by the equation:

Where, D = diameter of reactor (m) and L = tangent-to-tangent length of reactor (m). Let

L = 4D. Thus,

= 1.85 m

L = 4D = 4(1.85) = 7.4 m (291 in; 24.3ft)

The inside diameter of the vessel = 1.84 m (72.8 in; 6.07ft). Thus, the minimum wall thickness should be 0.0239 m (0.941 in; 0.0784ft).

The f.o.b. purchase cost of the vessel can be calculated by the equation: CP = FMCV + CPL where, FM = material factor, CV = vessel cost and CPL = added cost for platforms and ladders

For vertical vessel, Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (72.8 + 0.941)(291 + 0.8(72.8))(0.941×0.284) W = 21 621.75 lb Cv = exp{7.0132 + 0.18255[ln21 621] + 0.02297[ln21 621]2} Cv = $ 67 763.62 234

CPL= 361.8 (Di) 0.73960 (L) 0.70684 CPL= 361.8 (6.07) 0.73960 (24.3) 0.70684 CPL= $ 13 095.34 FM for carbon steel = 1.0 Thus, Cp = FMCv + CPL Cp = 1(26 879.58) + 6 258.50 + 427.82 Cp = $ 33 565.9

(550/500)(33 565.9) = $ 36 922.49 = RM 110 398.25

Table 5.10: Specification sheet for boiler, V-104 EQUIPMENT SPECIFICATION SHEET Identification : Boiler Item No.

: V-104

Function

: Change water to steam

Specification

Design Sizing

Design type Material construction

Vertical of Stainless steel 316

Operating Condition

Vessel volume

20 m3

Vessel diameter

1.85 m

Vessel length

7.4 m

Wall thickness

0.0239 m

Equipment Estimated Cost

Residence time

15 min

Operating temperature

327oC

Updates BMC (RM) 110 398.25

2.96 atm

Operating pressure 235

CHAPTER 6

PROCESS CONTROL

6.1

Introduction

The change of operating conditions, compositions and also physical properties of the streams the most important things we should avoid in our processes. Thus, the chemical plant must be satisfied with several requirements such as safety, production specifications, environmental regulations, operational constraints and economics in the presence of ever changing disturbance. A further complication is that the latest processes have become more difficult to operate because of the trend towards larger, highly integrated plants with smaller surge capacities between various processing units.

236

In order to reduce or decrease the negative impact that could result from such disturbances, we have implemented our plant with control mechanism substantial amounts of instrumentation and automatic control equipment. Therefore, several requirements and conditions have to be satisfied. The requirements are as follow:

i. Safety

For a typical chemical process, the primary requirement is the safe operation for the well being of the people in the plant and for its contribution to the economic development. Thus, the operating pressure, temperature, concentration of composition and others should always within allowable limits.

ii. Production specification

A plant should produce the desired amount and the quality of the final product. In this case, it is required the production of 450 L of Gaharu essential oil. Therefore, a control system is needed to ensure the production of Gaharu essential oil at the maximum level. Besides, maintaining the product composition within the specified quality standard is essential.

iii. Operating constraint

Various types of equipment used in the plant have operation constraints. Such constraint should be satisfied through operation of the plant. For example, the distillation column should not be flooded; temperature in a reactor should not exceed upper limit; tanks should not overflow or go dry; pH in incubator should 237

be maintain at specific level; pumps must be maintained at a certain net positive suction head. A control system should be set up to satisfy all these operational constraints.

iv. Economic

Before setting up a chemical plant, we should carry out some market survey and confirm with the market conditions, which is availability of raw materials and the demand of the final products. Furthermore, the plant should be as economic as possible in its utilization of raw materials, energy, capital and human resources. It is required that the operating condition is controlled at a given optimum level of minimum operating cost, maximum profit and others.

All the requirements are achieved by a combination of automatic control, manual monitoring and laboratory analysis. Instrument monitoring critical process variables will be fitted automatic alarms to alert the operators to critical and hazardous situations. There are three main classes of need a control system that is to satisfy:

i. Ensuring the stability of a chemical process. ii. Suppressing the influence of external disturbances. iii. Optimizing the performance of a chemical process.

The design of a control system for a chemical plant is made after a process flow sheet has been synthesized and design or even constructed to a significant detail. Thus, the control designers are allowed to know:

238

i. The range of operating conditions. ii. The process units the plant and their sizes. iii. How they are interconnected. iv. Possible disturbances, available measurements and manipulations. v. Problems which may arise during start-up and shutdown of the plant.

6.2

Control System Design

Basically control objectives must be first defined before developing a particular control schemes. After that, when a critical controlled variables are identified, whereby measured variables, manipulated variables must be decided to conceptualize the control strategies. The following procedures are used to identify and locate the control instrument in the process: i. Identify and draw in those control loops that are obviously needed for steady plant operation, such as:



Level controls



Flow controls



Pressure controls



Temperature controls



Composition controls

ii. Identify the key process variables that need to controlled to achieve the specified product quality includes controls loop by using direct measurement of the controlled variable, where possible. 239

iii. Identify and include those additional control loops for safe operation, not covered in steps (i) and (ii).

iv. Decide and show those auxiliary instrument needed for monitoring the plant operation by operators, trouble-shooting and plant development. It is well worthwhile including additional connections for instruments that may be needed for further trouble-shooting and developments are not installed permanently. These include pressure tapping, orifice and extra sample points.

v. Decide on the location of sample points.

vi. Decide on the need for recorders and location of the readout points, local or control room. This step would be done in conjunction with step (i) to (iv).

vii. Decide on the alarms and interlocks needed; this would be done in conjunction with the step (iii).

Normally, there are two types of control system, which are a feedback control and a feed forward control. In feedback control system, it is applied when measuring device detected the output of a process and then a controlling device will be compared between the measured reading and the process set point, and lastly the signal will be sent to the final control element that will manipulate the controlled variables.

Anyhow, a feed forward control configuration measures the disturbances (load) directly and takes control action to eliminate its impact on the process output. That is 240

mean a feed forward controller has the theoretical potential for perfect control. Most of the processing system in the chemical plant used the multiple input, multiple output system (MIMO) and single input, single output system (SISO).

6.3

Hardware Elements Of A Control System

The hardware elements that we can distinguish in every control configuration especially in the control system for production of 450 L of Gaharu essential oil are as follows:

Set point Command input

Controller

Feedback input

Final

Unit

Control

Operation

Process output

Element Measuremen

t Figure 6.1: Typical close loop control system

i. Chemical process

Present the material equipment together with the physical and chemical operations that occur in the plant.

241

ii. Measuring instruments or sensors:

Such instruments are used to measure the disturbances, the controlled output variables and the main sources of information about what is happened in the process.

iii. Transducers:

A measurement used to measure the control variables such as temperature, pressure, level, composition and flowrate. The examples of that equipment are thermocouples and venturi meter.

iv. Transmission

Carry the measurement signal from the measuring devices to the controller. The dashed lines represent electronic signals, while solid lines represent pneumatic controllers.

v. Controller: The element that has â&#x20AC;&#x17E;intelligenceâ&#x20AC;&#x;, because of its receiving the information from the measuring device and may decide what action should be taken. The two types of controllers are electronic controller and pneumatic controller.

vi. Final control element: This element serves as an intermediate between the process controller and process. 242

vii. Recording elements:

Provide a visual demonstration of how a chemical process behaves. Usually, the variables recorded are the variables that are directly measured as part of the control system. Various types of recorders are available such as temperature, pressure, flowrate and compositions recorders.

6.4

General Type of Control Configuration

Several common control strategies may include feedback control and feed forward control, together with other variations, such as cascade control, ratio control and inferential control.

6.4.1

Feed-Forward Control

In feed-forward control, the disturbance variable is measured and it is used to adjust the manipulated control in order to attenuate the disturbance, which could be introduced into the controlled variable. Feed-forward control does escalate tremendously, however, the requirements of the practitioner. The practitioner must know in advance what disturbance will be entering the process, and there must be adequate

243

provision to measure these disturbances. Figure shows a general conceptual framework of automatic feed-forward control.

Figure 6.2 Feed-Forward Control Concepts

Disturbances are shown entering the process and there are available sensors to measure these disturbances. Based on these sensed or measured values of the disturbances, the feed-forward controllers then calculate the needed values of the manipulated variables. Set points, which represent the desired values of the controlled variables, are provided to the feed forward controllers. Conclusively, feed-forward controller needs sophisticated calculations in order to achieve satisfactory performance.

6.4.2

Feedback Control

In feedback control, the process variable to be controlled or controlled variable is measured and the measurement is used to adjust the manipulated variable defined. 244

Feedback is by far the most commonly used and reliable system. This is because the system has the obvious advantage of greater accuracy than feed-forward control system. They are less sensitive to noise, disturbances, and changes in the environment. Transient response and steady-state error can be controlled more conveniently with greater flexibility in feedback control system, often by a simple adjustment of gain in the loop, and sometimes by redesigning the controller. Feedback control is widely used in industry. The concept of feedback control is illustrated by Figure 6.3.

Figure 6.3 Feedback Control Concepts

6.4.3

Inferential Control Configuration

Inferential control uses secondary measurements to adjust the values of the manipulated variables. This is because the controlled variables cannot be measured. The main objective of this kind of controller is to keep the unmeasured controlled variables at the desired levels. 245

The estimator uses the values of the available measures outputs, together with the material and energy balances that govern the process, to compute mathematically the values of the unmeasured controlled variables. These estimates are used by the controller to adjust the values of the manipulated variables. Figure shows a general structure of inferential control configuration.

Figure 6.4 General Structure of Inferential Control Configuration

6.4.4

Cascade Control

In cascade control, two controllers are cascaded together so that the output of one is the set point input of the other. This is illustrated in the linear block diagram of Figure. There are other control configurations in which the controllers are cascaded, but the term is usually applied to control cases that have two-loop control structure of Figure and where both measurements are process variables or manipulative inputs (instead of disturbance inputs).

246

U2 U1

GC1

GC2

GP2

GP1

Figure 6.5 Cascade Control Block Diagram

Based on this diagram, one can make the following observation:

Two process variables C1 and C2 are measured and used to actuate control. These are usually called the primary and secondary variables, respectively. The objective is the control of C1.

There are two feedback loops. The outer loop is called the primary loop and the controller GC1 is called the primary controller. The inner loop is called the secondary loop and contains the secondary controller GC2.

Only one process input is manipulated. As a result, there can only one degree of operational freedom, as represented by the single set point input, r.

The disturbances U1 and U2 are shown entering the linearized process model at four different locations so that one can consider the effect of disturbance location.

247

6.4.5

Ratio Control

Ratio control can be used when it is desired to maintain two flows at a constant ratio, where the controller at a stream controls the flow of the stream and it provides a signal to the ratio delay, which controls the set point of the controller of another stream.

6.5

Typical Control System

Below are descriptions for typical control system that is usually applied to a chemical plant. Some of them will be applied in this plant and some may not involved.

6.5.1

Level Control

In any equipment which an interface exists between two phases (e.g. liquidvapour), some means of maintaining the interface at the required level must be provided. This may be incorporated in the design of the equipment by automatic control of the flow from the equipment. The storage tanks would require automatic level control to control the flow from each of the equipment.

248

An increase in controller gain often brings an increase in system stability, while low controller gains can increase the degree of oscillation. Integral control action is normally used but is not necessary if small offsets in the liquid level (Âą5%) can be tolerated. Derivative action is not normally employed in level control, since the level measurements often contain noise due to splashing and turbulence of the liquid entering the tank

Usually, the liquid storage tank is used as a surge tank to damp out the fluctuations in its inlet streams. If the exit flow rate from the tank is used as the manipulated variable then the conservative controller settings should be applied to avoid large, rapid fluctuation in the exit flow rate. This strategy is referred to as averaging control. If a level control also involves heat transfer, such as in vaporizer of evaporator, the process model and controller design become much more complicated. In such situations, special control method can be advantageous.

Figure 6.6: Level Control.

6.5.2

Pressure Control

Pressure control will be necessary for most systems handling vapour or gas. The method of control will depend on the nature of the process. Gas pressure is relatively 249

easy to control except when the gas is in equilibrium with the liquid. A gas pressure process is self-regulating, the vessel or pipeline admits more feed when the pressure is low and the feed intake is reduced when the pressure becomes high. PI controllers are normally used with only a small amount of integral control action. Usually the vessel volume is not large, leading to relatively small residence times and time constant. Derivative action is normally not needed because the process response times are usually quite small compared to other process operation.

(a)

(b)

(c)

(d)

Figure 6.7: (a) Pressure control by direct venting (b) Venting of non-condensable after a condenser (c) Condenser pressure control by controlling coolant flow (d) Pressure control of a condenser by varying the heat-transfer area dependent on liquid level.

250

6.5.3

Flow Control

Flow control is usually associated with the inventory control in a storage tank or other equipment. Flow and liquid pressure control loops are characterized by the fats responses, with essentially no time delays. The process dynamic is due to compressibility (in a gas stream) or internal stream (in a liquid). The sensor and signal transmission line may introduce significant dynamic lags if pneumatic instruments are used. Disturbances in flow control systems tend to be frequent but generally not foe large magnitude. Most of the disturbances are high-frequency noise (periodic or random) due to stream turbulence, valve changes and pump vibrations. PI flow controllers are generally used with intermediate value of the controller gain Kc. The presence of recurring high-frequency noise rules out the use of derivative action. And to provide flow control on a compressor or a pump running at fixed speed and supplying a near constant volume output, a by-pass control would be used.

(a)

251

(b)

Figure 6.8: (a) Flow control for a reciprocating pump (b) Alternative scheme for a centrifugal compressor or pump.

6.5.4

Cascade Control

More advanced control strategies may be introduced to achieve certain control objectives more satisfactorily. In particular, cascade control structure is characterized by its two feedback controllers with the output of the primary controller changing the set point of the secondary controller where the output M the secondary goes to valve. The two purposes of cascade control are:

i. To eliminate the effects of some disturbances. ii. To improve the dynamic performance of the control loop.

252

6.5.5

Temperature Control

General guidelines for temperature control loops are difficult to state because of the wide variety of processes and equipment involving heat transfer and their different time-scales. For example, the temperature control problems are quite different for heat exchangers, distillation columns, chemical reactors, and evaporators. The presence of time delays and/or multiple thermal capacitances will usually place a stability limit on the controller gain.

6.5.5

Ratio Control

6.6

Process and Instrumentation Diagram

The process and instrumentation diagram provides a graphical representation of a control configuration for the process. It illustrates the measurement device, controller as well as actuator of the control loop. The standard measurement is developed base on the International Society for Measurement and Control (ISA) in developing out the plant P 253

& I diagram. The legends of P & I diagram with their description usually used in plant are listed below:

Table 6.1: Basic Symbols Used To Show the Valves, Instrument and Control Loops Hardware Element

Measurement TT

Controller TC

Alarm TC

Transmission Line

Symbol

Description

Temperature Transducer

Pressure Transducer

Level Transducer

Flow Transducer

FFT

Flow Ratio Transducer

Composition Transducer

Temperature Controller

Pressure Controller

Level Controller

Flow Controller

FFC

Flow Ratio Controller

Composition Controller

Temperature Alarm

Pressure Alarm

Level Alarm

_____________

Pneumatic Transmission Line

--------------------

Electric Transmission Line

254

6.7 Process Control System in Gaharu Essential Oil Plant.

6.7.1

Control System for the Cooler, P-4/ HX-101

SP-5

SP-6

Control System for the Cooler, P-4/ HX-101 Objective:  To cool the temperature from inlet stream to suitable temperature to be use for the next unit operation.

Control objective: 

Reduce the temperature at stream 5 from 121°C to 55°C in stream 6

Control

Measure

Manipulated

variables

Temperature at Temperature at Flow rate of stream 6

outlet stream 6

cooler

Disturbances

Change temperature

Configuration

in Feedback

inlet stream 5

255

6.7.2

Control System for the Pump, PM-101

PIC

SP-6

Control System for the Pump PM-101 Objective: ď&#x201A;ˇ

To control outlet pressure in order to achieve design pressure.

Control objective: ď&#x201A;ˇ

Ensuring the desired outlet pressure is achieved.

Control

Measure

Manipulated

variables

Outlet pressure Outlet pressure By-pass stream of pump stream of pump stream flowrate

Disturbances

Pump

inlet

stream pressure

Configuration

Feedback

256

6.7.3

Control System for the Condenser, P-8/ HX-101

Hot out

SP-11

SP-10

P-5

Cool in

Control System for the Condenser, P-8/ HX-101 Objective:  To cool the temperature from inlet stream to suitable temperature to be use for the next unit operation. Control objective: 

Reduce the temperature at stream 10 from 327°C to 25°C in stream 11 from heated gas to a liquid state.

Control

Measure

Manipulated

variables

variables Flow rate of

Outlet flow rate Outlet flow rate fuel

(heater)

temperature

cooling

temperature

water (cooler)

Disturbances

Change

Configuration

temperature

Feedback

inlet stream 10

257

6.7.4

Control System for the Autoclave

PC SP-3 SP-5 SP-4

Control System for the Autoclave Objective: ď&#x201A;ˇ To cool the temperature from inlet stream to suitable temperature to be use for the next unit operation. Control objective: ď&#x201A;ˇ

To control the pressure and temperature outlet of autoclave at stream 5.

Control

Measure

Manipulated

variables

Outlet

temperature

flowrate

Outlet pressure

flowrate cooler

Configuration

Feed flowrate

Feedback

Feed flowrate

Steam Outlet pressure

Disturbances

Pressure

Feedback

aoutoclave 258

6.7.5

Control System for the Incubator

SP-6 SP-9

SP8

P-11

pHT

Control System for the Incubator Objective: 

To maintain an optimum operating condition for the incubator so that the process will occur in a safer operating system. Control objective:



To control the pH in the incubator at 4.5 – 5.5.

Control

Measure

Manipulated

variables

variables Flow rate of

pH in incubator

pH of mixture sodium in the incubator

hydroxide stream 8

Disturbances

Configuration

Inconsistent flow

rate

Feedback

stream 8

259

6.7.6

Control System for the Boiler

TT TC

SP-13

Control System for the Boiler Objective: ď&#x201A;ˇ To supply heated steam to be used for the next unit operation.

Control objective: ď&#x201A;ˇ

To control the desired temperature for steam supply at 329 oC at stream 13.

Control

Measure

Manipulated

variables

Outlet

temperature

Temperature inside boiler

Disturbances

Configuration

Change in heat

the supply for the

Feedback

boiler

260

6.7.7

Control System for the Distillation still

Control System for the Distillation still Objective: 

To maintain an optimum operating condition for the Distillation column so that the process will occur in a safer operating system.

Control objective: 

Control pressure in the column at desired values



Control column liquid level at desired values



Control inlet flow rate to the column at desired values

Control

Measure

Manipulated

variables

Disturbances

Configuration

261

Liquid level in Liquid level in Bottom the column

the column

Operating

pressure in the pressure in the column

column

Amount of feed Amount of feed to the column

6.8

to the column

flowrate S14

Distillate flowrate

Feed stream Feedback flowrate Feed pressure

stream and

Feedback

flowrate

Flowrate

of Feed flowrate feed stream to

Feedback

column.

Conclusion

Designing control systems for complete chemical plants is the ultimate goal for control designer. The problem is quite large and complex. It involves a large number of theoretical and practical considerations such as quality of controlled responses, stability, safety of the operating plant, the reliability of the controlled systems, the range of control and ease of startup, shutdown, or change over, ease of operation, and the cost of the control system. A chemical plant must satisfy several requirements imposed by its designers and the general technical, economics and social conditions in the presence of any influences (disturbances).

Pressure is parameter that will affect the thermodynamic equilibrium of two interacting phases. Therefore, the pressure has to be maintained at set pressure for efficient separation. The control objectives in this case are to maintain the operating of 262

the cooler, pump, distillation column, incubator, autoclave and condenser. In this Gaharu essential oil plant, it has been dedicated to select a strain gauge due to the fact that it has a good accuracy, good stability, fast response, and good shock and vibration characteristic for safety matter, all the bypass manual valves should be available at reach installed control valves. The reason is to avoid total shutdown of the process while calibration, maintenance, repair or replacement is implemented. In addition, it will take effect when an emergency condition occurs and the particular control valve is malfunctioning or it has a slow response.

Control valves are needed as the final control elements in the plant. The control valves are selected to be used are the globe valves because its provide a high range ability and reversible ports and plugs. There are two types of globe valves, the single port globe is used in sized under 2 inch and the double port globe is used in sizes larger than 2 inch. The double port globe valve has a higher flow capacity compared to single port globe valve of the same size. Pressure relief valves are needed in the flash column, distillation column and reactor for safety purposes.

The operation of a plant must conform to market conditions, which are the availability of raw materials and the demand of the final products. Furthermore, it must be as economical as possible in its utilization of raw materials, energy, capital, and human labor. Thus it is required that the operating condition are controlled at given optimum levels of minimum operating costs, maximum profit and other related matters.

263

Cool Out SP-10 TT

T= 55°C P=1 atm pH= 4.5

SP-11 Evaporator

SP-6(2) SP-9(2) Incubator

pHT

PIC

SP-2 T=121°C P=1 atm

SP-1

Mixer

SP-8(2)

T= 55°C P=1 atm pH= 4.5

TC PT FC FT

SP-6

T= 329°C P=1 atm

Oil Separator

Boiler

Distillation Still

Cool In

SP-9 Incubator

SP-9

SP-3 SP-5

pHT

SP-6

SP-8

SP-6(3) Pump

Autoclave

T= 327°C P=1 atm

Incubator FC

SP-9(3)

TC pHT

Gaharu

SP-8(3)

T= 55°C P=1 atm pH= 4.5

Grinder SP-4 Waste SP-14

Figure 6.9: Piping and Instrumentation Diagram (P&ID)

264

CHAPTER 7

PROCESS SAFETY STUDY

7.1

Introduction

Chemical engineers will need a more detailed and fundamental understanding of safety.

According to H. H. Fawcett: â&#x20AC;&#x153;To know is to survive and to ignore fundamentals is to court disaster.â&#x20AC;?

Today, safety is equal in importance to production and has developed into scientific discipline, which includes many highly technical and complex theories and practices. The Health and Safety at Work (Act 1974) provided a new legal administrative framework to promote, simulate, and encourage even higher standards of 265

health and safety at work. In chemical plant, the main hazards are toxic and corrosive chemicals, explosions, fires and accidents common to all industrial activities. Table 7.1 shows the frequently used term and their definitions in chemical process.

Table 7.1: Frequently Used Term and Their Definitions

Terms

Definitions

Prevention of accidents by the use of appropriate

Safety / Loss

Prevention

technologies to identify the hazards of a chemical plant and to eliminate them before an accident occurs.

2. Hazard

Anything with the potential for producing an accident.

3. Risk

Probability of a hazard resulting in an accident.

To conduct a safe and productive plant, such as this banana paper plant, a successful safety program is required which consists of safety knowledge, safety experience, technical competence, safety management support, and commitment.

In this chapter, general safety procedure, only the identification and assessment of hazards, start-up and shutdown procedure will be discussed. Most of the industrial process is nearly hazardous but chemical processes have additional hazard chemicals and also in the process condition. The hazards existed in same chemical because of it liability to expose or react vigorously on contact with other components.

266

In this chapter, the aspect of hazards is viewed the plant and the process condition. The designer must be aware of these hazards, and ensure that the risks are reduced to acceptable levels. This can be achieve by identifying the sources of hazards and take all appropriate steps to secure them. The particular hazards associated with the chemicals used and processes will be briefly discussed.

For our plant, the scopes below are work as an effort in the process safety development.  General plant safety  Material Safety Data Sheet (MSDS)  Hazard and Operability Study (HAZOP)  Site and Plant Layout  Plant Start-up and Shut-do

7.2

General Plant Safety

As been stated in the introduction part of this chapter, process safety study plays an important role in designing a chemical plant. In this part, an introduction to general plant safety such as concept hazard analysis, hazard and operability studies will be discussed. Due to the presence of steam can cause severe bums, the workers in the plant should be thoroughly informed of the safety procedure before plant start operating.

7.2.1

Chemical Storage and Process Vessels 267

In general, chemical are hazardous materials in that strong hydrating agents, acids and bases and oxidizing agents can destroy living tissue, and the eyes, nose and throat are particularly sensitive to dusts, mists and many gases and vapors. It is vital to specify the installation of first aid functional safety sprays. Under Section 24 (Personal protective clothing and appliances), Factories And Machinery Act 1967 (Act 139), it has been stated that in any factory, those persons who are exposed to a wet or dusty process, to noise, to heat or to any poisonous, corrosive or other injurious substance, they must be provided with those suitable and adequate personal protective clothing and appliances.

The chemical storage is important because it has a huge amount of raw material or complicated product along with chemicals used for other. All flammable gases and flammable liquids (flash point < 40oC) are assumed capable of supporting a Vapor Cloud Explosion (VCE). The storage of such chemicals is important to avoid any form of unnecessary risk.

The design of the storage tanks should be considered properly in order to eliminate the possibilities of fireball, VCE and toxic cloud. They should be well isolated by automatic or remotely operated valves to minimize escapes. The escape of VCE from process vessels should not be ignored especially from a high pressure gas filled equipment and moderate to low pressure equipment. So as the possibilities of escape from other parts such as pumps, stirrer glands, heat exchanger tubes and pipe work which are more likely to fail.

7.2.2

Transportation

268

Many accidental releases of dangerous liquids in process plants have occurred at road and rail tanker loading and unloading stations.

This is hardly surprising

considering the different hazards, which concentrate and interact at these points. They include:



Vehicle hazards – collisions, error in parking position, unauthorized starting, and damage to and poor maintenance of vehicles



Hazards of temporary hose and solid pipe connections



Hazards of ignition both from vehicle engines and from electricity



Hazards of overfilling and errors in sequence of valve opening and closing

Loading and offloading should only be allowed at carefully selected sites where necessary facilities are installed. It should be within but near the perimeter fence, in paved, levelled or concreted areas. The bay must be clearly marked and provided with light roofs and upper side coverings to protect against sun and driving rain, but without end wall for easy through-transit of vehicles and good natural ventilation. Only vehicles approved for the liquid in question may be used.

7.2.3

Housekeeping

Chemicals and volatile flammable liquids should be stored and handled in authorized and clearly marked containers, which are kept closed. Methods to be used for dealing with spillages of particular hazardous liquids and accumulations of dangerous dust must be clearly stated in the standing instructions and followed promptly. Operations involving hazardous dusts should be allow where there is proper 269

local exhaust ventilation and other facilities needed to protect the worker. Regular inspection is needed to ensure that good housekeeping and regular cleaning are enforced. Exits should not be blocked for easy movements during emergencies. Objects must not be placed under safety showers or block access to fire fighting equipment. Clear responsibilities for the receipt, storage and issue of materials used in processes must be established. Proper arrangements for inventory control, records and security must be made.

7.2.4

Utility

Plants should be designed so that the sudden failure of one or more utility supplies does not prove disastrous. The routing of service supplies should be as secure as possible. The position of underground supplies should be clearly marked on drawings and where possible by ground posts.

Underground supplies must be adequately

protected from heavy vehicles.

Electricity

The use of flameproof and intrinsically safe electrical equipment and conduit is to reduce the risk of flammable gases, vapors and dusts. A â&#x20AC;&#x17E;hazardous zone drawingâ&#x20AC;&#x; is made when all sources of leaks of flammable materials have been identified. This shows the categories of electrical equipment allowed in each zone. Loss of electrical power is especially serious if it causes materials to solidify in a process or pipeline, air-cooled and refrigerated heat exchangers to cease functioning and cooling water and process pumps 270

to fail. Reliable back-up systems, which are ultimately reliant on local battery power packs, are especially important. To prevent electrical shock insure that all equipment are properly grounded. The entire wiring and electrical component should comply with the standard of the local authority. Check all equipment regularly to prevent accidents.

ii.

Cooling Water

Problems found in cooling water include corrosion, scaling and the growth of mollusks and the presence of solid objects, which block heat exchanger tubes, small valves and lines. This requires expert study to kill algae and mollusks; and to control pH, scaling, precipitation and corrosion. A sometime serious problem of circulating cooling water systems is the day-to-night temperature fluctuations, which cause process disturbances. In the cases where cooling water failure is serious, stand-by pumps provided with an alternative power source are often installed.

7.3

Worker Safety

There are a few basic safety rules to protect the personnel, which must be observed when working in all chemical manufacturing areas. The workers in the plant should be thoroughly informed of the safety procedure before plant start operating.

7.3.1

General Personnel Safety

Each employee is expected to know and observe all safety instructions and danger signs. It is part of their job safety and correctly. For example, know how

271

to use all types of fire extinguishers, fire hoses, fire blankets, the location of escape routes. ii.

The employer is responsible for their fellow employeeâ&#x20AC;&#x;s safety.

iii.

No smoking, except in specific areas designated for smoking.

iv.

No eating, drinking except of water fountains.

No flammable chemical substances, drugs allowed bringing into the plant, except in need.

vi.

The area around the unit should be positioned in a level, which is sufficiently to provide reasonable safety of movement by workers.

vii.

Do not enter processing areas other than the place of work.

viii.

Detective equipment, unsafe conditions and unsafe practices must be reported to the Supervisor as soon as discovered.

ix.

All unclear, accident, injuries must get report at once to the Supervisor for the next instruction.

Get immediate medical attention for injuries, however minor they appear to be. Each employee should explore the basic first-aid poison information.

xi.

Every visitor must get the permission and be instructed of plant safety rules before they are allowed to enter the plant.

xii.

Wear all personal protective clothing and equipment provided while in the plant to minimize risk of injuries should the unexpected happen.

7.3.2

Personal Protective Equipment

All necessary technical improvements must be taken before resorting to use of personal protective equipment. An adequate number of personal protective equipment is in a variety of material is generally available. The chemical operative should seek for the suitable type for the work being done. Workers should be trained to use personal 272

protective equipment correctly and whenever necessary. It is a responsibility for the employee to provide complete and clean personal protective equipment to the workers.

7.3.2.1 Safety Hats

Soft caps of plastic or leather give protection against chemical splashes, especially when working with overhead pipes, tanks, heat exchangers and other equipment, which may leak. Reinforced hats of metal, laminated plastics, or other materials resistant to impact from falling objects should be worn when overhead work is performed (a properly fitting hat gives maximum protection).

7.3.2.2 Face Shields

Face shields provide an excellent protection to the eyes and face as protection against airborne particles or flying objects.

The shield should be made of a

nonflammable material and remain scratch-free so as to avoid distortion.

7.3.2.3 Goggles 273

Goggles are eye protective equipments, which are commonly used to protect eyes from airborne particles, injurious light or heat rays. Spectacle goggles mainly provide protection from both the front and side against flying objects. Plastic hydron goggles mainly provide protection against splashing liquid and vapors and will not fog up during use. Coverall type eye shield is most preferred because of its lightweight and convenience and provides very good protection against splashing from. The coverall type has a short useful life.

7.3.2.4 Air Mask

The most common air masks are the “army gas-mask” type: a moulded rubber front with two eye ports is held to face by adjustable elastic straps fitting around the head. Air is drawn through a flexible hose and a non-return valve, in front of the mouth, from a canister strapped to the body, and is expelled between the cheeks and the rubber sides of the mask. The canister contains a suitable, absorbent material and it is therefore of vital importance to distinguish the correct canister for the conditions to be entered. Check with a supervisor, there is a limited life before the absorbent material is spent and it is susceptible to deterioration, so immediately area.

To obtain protection over longer periods, there are similar masks which are supplied by air from a compressed air line or cylinder or from a hand or electrically driven blower (positioned in the “ fresh air”). The canister type mask gives the wearer the most freedom of movement and those connected to the blower the least. There is a danger of the trailing airlines becoming jammed or cut or of tripping up the wearer.

274

7.3.2.5 Safety Footwear

Industrial safety shoes and boots, with steel toecaps, which are of good appearance and comfortable are supplied free or at reduced cost. Ordinary shoes are most unsuitable as they offer little resistance to corrosive chemicals or to falling objects. Sparks from nailed boots are a source of danger. Rubber boots are watertight and resistant to most corrosive chemicals, but may be attacked by many organic solvents.

7.3.3

First Aid

First aid is generally defined as emergency treatment and skilled help provided to an injured, drowning, unconscious or suddenly ill person before professional medical help arrives. Normally first aid kits box is attached on the easily seen wall and should be easily to be taken when emergency comes up. The content of first aid kits box is depends on the condition of the industries, but in a normal box the entire list below is compulsory:

Move victim to fresh air; call emergency medical care.

If not breathing, give artificial respiration (CPR).

If breathing is difficult, give oxygen.

Remove and isolate contaminated clothing and shoes at the site.

In case of contact with mineral, immediately flush skin or eyes with running water for at least 15 minutes.

Keep victim quiet and maintain normal body temperature.

Effects may be delayed; keep victim under observation. 275

7.4

Fire Hazards

In the plant, the major hazard that may occur is the fires that will possible proceed to an explosion. Thus, fire risk management is essential. The prevention of flammable gases in the process stream, will give a sensible threat of the fire hazard to the plant. A major factor in the management of risk is ensuring that employees work safely to prevent fire and to respond correctly if fire occurs. The two primary ways to manage fire risks are:

To prevent fire

To limit or control fire if it occurs

7.4.1 Fire Prevention and Safety Procedures

In the plant, the major hazard that may occur is fire that will possible proceed to an explosion. The present of flammable gases in the process stream will give a sensible threat of fire hazard to the plant. Therefore, the availability of any fires extinguisher medium such as water supplies, fire and hydrants and foam is compulsory. Furthermore, the safety procedures are required to handle the emergency situation (Crowl and Louvar, 1990).

Fire Extinguishers

276

Fixed extinguishing system components and shall be designed and approved by the local authority for use on the specific fire hazards they are expected to control or extinguish. The routines check on any flammable substances and operation that operate in or near flammability limit should be done. Periodically check to investigate any sign of leakage. Portable fire extinguisher should be located near enough to the hazard to be immediately accessible, but far enough so that the fire will not prevent the use of it.

Fire extinguishers are labeled as to the kind of fire they will be effective against. The user must read the label to be sure that the appropriate equipment is used to extinguish the fire. Labels will indicates: Class A. Class B, Class C.

Class A Fires: In a fire involving wood, paper, cloth, trash, etc, extinguish by using water-base extinguisher, fire hose or multi-purpose dry chemical extinguishers.

Class B Fires: In a fire involving flammable liquids or chemical, extinguisher by using a CO2 or dry chemical extinguishers. Do not use water extinguisher or a fire hose, as the flowing water would spread the burning liquid.

Class C Fires: In a fire involving electrical equipment, extinguish by using a CO2 or dry chemical extinguisher. Do not use water-type extinguisher or fire hose, as water is a conductor of electricity.

The instructions of using the fire extinguisher have to be labeled clearly.

277

natural gas leaks with an open flame. Automatic detection equipment shall be approved, installed and maintenance to detect any present of fire (Crowl and Jouvar, 1990).

Extinguisher Use Instruction 

Check the label and carry extinguisher to vicinity of fire.



Remove the ring pin by pilling.



Squeeze discharge lever.



Direct discharge nozzle at base of fire.



Be sure all the fire is out before stopping discharge.



Back away from extinguisher fire.

Fire Detector

Thermal fire detectors that can be classified as rate-temperature-rise detectors and overheat detectors are not subject to frequent failure. To cover a large area or volume, many thermal detectors are required and they must be located at or very near the site of a fire.

Optical sensors for detecting fires operate in two spectral regions, ultraviolet and infrared. In general, different sensors and optical components must be used in each region. Closed-circuit infrared and ultraviolet remote-viewing systems, equipped with appropriate filters, have been used successfully.

Fire detection systems should systems, triggered by multiple fire detectors and activated quickly enough to prevent large-scale damage, should be considered. Connecting an automatic shutdown system to a fire-detecting system may not always be effective since alarms may be triggered by reflections from allowable fires (burn ponds and flare stacks) and sunlight (Md. Wijayannudin, 2004) 278

The routine check of any sign of leak of hazard materials can also be done. The DOW checklist can be used to estimate the potential hazard in the workplace.

Fire Alarms

Fire alarm system should be installed in most of the building of the plant. The sole function of the alarm system is to warn persons in building that an emergency has occurred and that the building occupants should be taking immediate action to vacate the building. At the same time, it alerts the Fire Department, which responds immediately.

Unless otherwise informed, such as during repairs to the system or monthly testing, anyone hearing a fire alarm should react immediately and be prepared to evacuate during normal operating hours (Crowl and Louvar, 1990).

Housekeeping

A good housekeeping is also another essential principal for fire prevention.

Keep working areas clean, clear and tidy.

ii)

Place waste in the containers provided.

iii)

Smoke only in those areas where it is permitted.

iv)

Place cigarette butts in safety ashtrays.

Adhere to proper material handling procedures.

vi)

Follow operational procedure of equipments.

279

7.4.2

The Plant Progress

Aside from the fact that plant are designed to operate in an efficient and economical manner, they must also be designed to operate so that possibility of fires and accidents are reduced or prevented. Where hazards are of flammable material, then containment of these hazards within restricted areas or buildings should be adhered to during facility designing.

Flammable liquids shall be kept in approved safety cans for use in small amounts and for transportation. These containers shall be clearly labeled and stored in a separate, protected area. Refueling a small engine that is running or is hot can be dangerous. This step should be avoided. Always clean up spills that occur during refueling before restarting the engines. Rags that contain oils or solvents shall be kept in covered metal containers until they can be safety disposed of. Never check for possible natural gas leaks with an open flame. Automatic detection equipment shall be approved, installed and maintenance to detect any present of fire. The routine check of any sign of leak of hazard materials can also be done. The DOW checklist can be used to estimate the potential hazard in the workplace.

7.5

Emergency Response

The main objectives of an emergency plan are to: i.

Rescue victims and treat them.

ii.

Safeguard others, arranging for their escape or evacuation.

iii.

Contain the incident and control it with minimum damage. 280

iv.

Identify the dead.

Inform relatives of casualties.

vi.

Provide reliable information.

vii.

Preserve relevant records, equipment and samples which may be needed as evidence

To achieve these objectives, the plan should make the best possible use of works and outside services and personnel. Emergency plan should be simple and flexible. Outside authorities must be prepared to deal with the effects of major accidents. They include police, ambulance, hospital and other authority services.

All personnel liable to be needed in an emergency should carry means of quick identification to avoid delays. The work incident controller will proceed to the scene, assess the scale of the emergency, take responsibility and activate the major emergency procedure. The absence of works main controller, the incident controller will direct shutting down and evacuate the affected plant and ensure that outside services and key personnel have been called in.

The works main controller will go to the emergency control center as soon as he aware of the emergency and take over from whoever deputizing for him. His duties among others are calling in outside services and key personnel, exercising operational control over those parts of the works outside the affected area, directing the shutting down of plants, the evacuation of personnel, ensuring that casualties are attended to, controlling traffic movement in the works, recording or arranging for a chronological record of the emergency to be made; and liaising with companyâ&#x20AC;&#x;s head office.

Checkers on each shift should proceed immediately to each assembly point once a major emergency is declared with a list of names of all persons known to be at work. A

281

mobile analytical team will provide rapid analyses of the atmosphere for harmful substances so that the works main controller has reliable information on the extent and spread of toxic and flammable materials.

Two or more clearly marked assembly points should be chosen in safe places on different sides and away from areas at risk. The emergency plan should also include measures, which ensure that personnel in these areas are quickly warned if and when they should shut down operations and evacuate. Automatic shutdown systems, triggered by multiple fire detectors and activated quickly enough to prevent large-scale damage, should be considered.

7.5.1

Emergency Control Center

At least one pre-arranged emergency control center should be established with proper communication with area around the works, as well as maps, site plans and relevant data and equipment to assist in any emergencies. The center should be close to the scene of possible incidents, but sufficiently far and well protected; and close to a road to allow ready access.

7.5.2

Fire Alarms and Declaring Emergency

282

Every work should be provided with a sounding alarm so that it can be heard everywhere in the work. The alarm should be actuated by an electrical signaling system with enough call points spread over the work for the alert to be raised by anyone.

The alarm may also be triggered by suitable fire and/or gas detectors. Automatic detection equipment should be approved, installed and maintained to detect any present of fire. Some of the detectors include thermal and optical sensors. Thermal detectors are capable of detecting temperature rise around the work area. While optical sensors detect invisible fires operate in ultraviolet and infrared regions.

7.5.3

Fire Protection

Fire protection equipment such as water hose reels, hydrants, foam, portable extinguishers, sand buckets and fire blankets should be made available for any minor hazard in chemical industries. Fixed extinguishing system such as wet and dry sprinklers, water and steam curtains; and foam pourers in tanks shall be designed and approved by the local authority for the use on the specific fire hazards. Portable fire extinguisher should be located near enough to the hazard to be immediately accessible. Routine check for all fire extinguishers should be done.

7.5.4

Label and Signs

283

Seeing that equipment is clearly and adequately labeled and checking from time to time to make sure that the labels and signs are still there is a dull job, providing no opportunity to exercise technical or intellectual skills. Nevertheless, it is as important as more demanding tasks.

7.6

Leakage Prevention

Most of the materials handled will not burn or explode unless mixed with air in certain proportions. The main problem in preventing fires and explosions is thus preventing the process material leaking out of the plant that is, maintaining plant integrity. Similarly, if toxic or corrosive materials are handled, they are hazardous only when they leak. Some common sources of leaks include small cocks that have been knocked open or have vibrated open, drain valves left open while draining water from storage tanks or process equipment, vents, hoses; and plugs that have been blown out of equipment.

Emission and exposure control are based upon leak measurement techniques that have been standardized by the EPA. These measurements are generally obtained at the emission source with the instruments that provide the concentration in air of the contaminant.

Identification of equipment must be monitored. In general the equipment includes in the monitoring are pump seals, valves, compressor seals, control valves and pressure relief valves. Screening instruments used in these services determine emission 284

leakage through various detection methods such as ionization, infrared absorption and catalytic conversion, which measure thermal conductivity or heat of combustion (Crowl and Louvar, 1990).

7.6.1

Control of Leaks

Many fires have been prevented or quickly extinguished by remotely operated Emergency Isolation Valves (EIVs). Once the leak starts, particularly if it ignites, it is usually impossible to approach the normal hand-isolation valve to close them. So, EIVs are the best solution for prevention of larger hazard.

These EIVs can be operated electrically, pneumatically or in some cases, hydraulically. They should be regularly inspected to ensure standards and to prevent stiffness and inoperable condition when required. EIVs should be placed where there are not likely to be affected by fire or provide the with fire protection. The impulse lines leading to EIVs should also be fire-protected. The operation of an EIV should automatically shut down any pump in the line and trip fuel supply.

Other means of controlling leaks include:

Injecting water so that it leaks out instead of oil. However, water pressure should be higher than oil pressure

ii.

Reducing the plant pressure to reduce the size of leak

iii.

Closing isolation valve some distance away

285

iv.

Freezing pipeline. This require time to organize the necessary equipment and can be used for materials of high freezing point

Injecting a sealing fluid into leaking flange or valve gland

vi.

Confining the spread of the leak by water spray or steam curtains

vii.

Controlling the evaporation from liquid pools by covering with foam

7.6.2

Detection of Leaks

Combustible gas detectors have detected a leak soon after it started and action to control it has been taken promptly. Installation of these detectors is strongly recommended whenever liquefied flammable gases or other flashing liquids are handled or experience shows there is a significant chance of leak.

The detection system design shall ensure that the systems expected response time is rapid enough to be compatible with the fire detection or other safety systems. These detectors should also capable of detecting leaks at lower flammability limit. Reliable flammable detection and monitoring system shall give warning when the worst allowable condition has been exceeded. These allowable conditions must be in the safe range, and the warning should indicate the hazardous concentrations. The system should also locate the source of flammable gases leak within the facility during the operations. To ensure acceptable performance, periodic maintenance and field recalibration of the detectors shall be conducted for every 6 months and facility records of this recalibration shall be maintained (MdWijayannudin, 2004)

286

7.6.3

Leaking Protective Equipment

Personal protective equipment selection shall be based on an evaluation of the performance characteristics of the PPE relative to the requirements and limitations of the sites, the task-specific conditions and the hazards identified at the site.

Instrumentation protective system that is trips, alarm interlocks. Air monitoring and alarm should also be tested regularly. Air monitoring shall be used to identify and qualify airborne levels of hazardous substances, safety and health hazard in order to determine the appropriate level of employee protection needed in site. An employee alarm system shall be installed as a signal when an emergency case happens.

7.7

Active Protective Systems

Active protective systems often provided cheaper and more practical solution than is possible by incorporating equivalent passive protection into the plant design.

processes where pressure can build rapidly, especially during an accident, it is crucial that a design team provide a method for relieving pressure. The risk of rupturing process equipment and releasing its content through accidental over-pressure beyond design limits has led to the extensive use of pressure-relief systems which release the contained process fluids when certain pressure is exceeded and dispose of them safely.

287

A pressure-relief valve is any type of automatic pressure relieving valve operated by its upstream pressure. It includes the following three types: 1) A relief valve which opens in proportion to the pressure increase, 2) A safety valve which â&#x20AC;&#x17E;popsâ&#x20AC;&#x; wide open when operating pressure is reached; and 3) A safety-relief valve can be used as a safety or relief valve depending in application.

All critical points of operation in a plant are normally protected by alarms and/or shutdown devices which are actuated by micro-switches triggered by high or low pressures, flows, levels, temperatures, etc. An audible/visual alarm is actuated when the variable deviates from normal and reaches a certain figure, to allow the operator to take corrective action. If this is not successful, a shutdown device may be actuated, shuts down one or more sections of the plant.

Interlocks are used to ensure that all pre-start conditions are met and that the correct sequence is followed. They are also used to prevent unauthorized entry to electrical switch rooms, process vessels, and cubicles where explosives are tested; and to prevent control instruments being decommissioned for calibration or maintenance unless safe conditions are met.

7.8

Monitoring For Safety

Continuous analytical control is sometimes vital to safety. Many process analyzers whose main function is to monitor the purity or quality of the product also provide a warning when something goes dangerously wrong with the process. 288

Other continuous instruments detect fires and flammable and toxic gases in the atmosphere. The choice of method and location of detectors require case-by-case study, not only to ensure rapid response but also to avoid false alarms. There are two problems to be overcome in designing detectors: 1) to ensure that the detector does not become source of ignition and 2) to make certain that it responds fast enough for effective action to be taken.

7.9

Material Safety Data Sheet (MSDS)

MSDS is the most important references used during the industrial hygiene study involving toxic chemicals. MSDSs are available from the chemical manufacturer, a commercial sources and a private library developed by the chemical plant. Interpretation of physical, chemical, and toxicological properties is needed to determine the hazards associated with a chemical. Proper control and handling of these chemicals can be developed based on these properties.

A Material Safety Data Sheet (MSDS) is designed to provide both workers and emergency personnel with the proper procedures for handling or working with that substance. MSDS will include information such as physical data (melting point, boiling point, flash point etc.), toxicity, health effects, first aid, reactivity, storage, disposal, protective equipment, and spill/leak procedures. These are of particular use if a spill or other accident occurs.

289

The MSDS is a comprehensive source of information for all types of employers. There may be information on the MSDS that is not useful to you or not important to the safety and health in your particular operation. Concentrate on the information that is applicable to your situation. Generally, hazard information and protective measures should be the focus of concern.

7.10

HAZOP Study

7.10.1 What is HAZOP

The technique of Hazard and Operability Studies, or in more common terms HAZOPS, has been used and developed over approximately four decades for 'identifying potential hazards and operability problems' caused by 'deviations from the design intent' of both new and existing process plants. Before progressing further, it might be as well to clarify some aspects of these statements. HAZOP technique is accepted in the process industries for its intrinsic value as a safety management tool. While the structure of HAZOP is almost standard, the methods and techniques vary considerably. Increasingly, computers are being used to assist with the process of performing the HAZOP and for producing the documentation.

On conclusion of a HAZOP, there should be quality documentation to demonstrate that it was performed comprehensively, that the rationale was sound and that it provides an action plan. Statutory authorities now require, not only that HAZOP's be performed, but also that they be performed to some acceptable standards. This part discusses the issues of productivity in the performance of HAZOP and audibility of the 290

results. Productivity is an issue of interest to management, and audibility is an issue of interest to both management and statutory authorities. Accurate, quality documentation of HAZOP‟s is important from the point of view of management accountability to satisfy both the statutory authorities and management‟s own corporate responsibilities.

7.10.2 The Objectives of HAZOP

To identify hazards or deficiency and potential operability problems which may lead to hazards such as fire, explosion, toxic release or reduce productivity

ii.

To critically examine the inadequacies in systems by considering is as a fully integrated dynamic unit, rather than the „ad hoc‟ design approach

iii.

To coordinate the various discipline involved in the project and provide a means for systematic analysis of the system

iv.

To reduce cost due to operability problems in increasingly larger and complexity plants so that profitability is increased.

To meet the legislative requirements for example, DOSH

vi.

To identify and prevent hazards in process plants that are growing in complexity with standards are no longer adequate.

7.10.3 Hazard and Operability Studies

In this project this safety procedure will be used to study the safety of the plant designed. This procedure is preferred since it is a formal systematic examination of a 291

processing plant for identifying hazards, failure and operability problems and assessing the consequence from such operation (Daniel A. Crowl, 1990). This leads to fewer lapses in safety, quality and production provided that the plant is installed according to the design and maintained in appropriate condition.

A HAZOP is carried out as a team activity. The P&ID of a plant are examined one by one at the detailed design stage. The HAZOP can also be used as a check on the operability of an existing plant. The procedure for a HAZOP study is to apply a number of guide words to various parts of the process design intention, which tells us what, the process is, expected to do. These guidewords are given above and are applied to all the unit operations to be considered.

The following words are used in a special way, and have the precise meanings given below:



Intention: the intention defines how the particular part of the process was intended to operate and the intention of the designer.



Deviations: these are departures from the designer‟s intention which are detected by



The systematic application of the guidewords.



Causes: reasons why, and how, the deviations could occur. Only if a deviation can



Be shown to have a realistic cause is it treated as meaningful.



Consequences: the results that follow the occurrence of a meaningful deviation.



Hazards: consequences that can cause damage (loss) or injury.

Its key feature is the ability to examine most process deviations, although all the causes and consequence of these deviations may not be diagnosed. It suggests necessary changes to a system or suggests procedures for eliminating or reducing the probability of operating deviations. It assists in the decision-making required to reduce all identified

292

hazards to a tolerable level of risk as defined by the current company guidelines. In the following part, HAZOP study on various unit operations will be carried out.

7.10.4 Basic Principles of HAZOP Studies

In this study, there are series of words, which are used due to the process parameters in order to identify the undesired process deviations. The study contains the important guide words are described in Table 7.2. Table 7.2: HAZOP Guide Words Guide Word

Meaning

Comment

NO or NOT

The complete negation of these intentions

No part of the intentions is achieved but nothing else happens.

MORE or LESS

Quantitative increases or decreases

These refer to quantities and properties such as flow rate and temperature as well activity likes 'Heat' and 'React'.

AS WELL AS

A qualitative All the design and operating intentions are achieved together with some increases additional activity. A qualitative Only some of the attention achieved; decrease some are not.

PART OF REVERSE

The logical opposite This is more applicable to activities for example reverse flow or chemical of the intention reaction. It can also be applied to substances such 'Poison' instead of 'Antidote'.

OTHER THAN

Complete substitution No part of the original intention is achieved. Something quite different happens.

293

7.10.5 HAZOP Procedure

Figure 7.1: The flow sheet of HAZOP Procedure.

294

7.10.6 HAZOP Study on Various Operation Units

In this section, the HAZOP technique is applied in process safety study by taking some major equipment as examples. Detail discussion will be given to the HAZOP studies on heat exchanger, reactor and others. When applied to these major unit operations, HAZOP studies identify potential hazards, which may arise from the deviations, and appropriate actions that should be taken.

7.10.7 HAZOP Studies on the Selected Equipments

In this section, the detail discussion on HAZOP studies will cover the reactor, tank, mixer, heat exchanger and evaporator. When the studies are applied to this equipment, the potential hazards, which may arise from the deviations and the appropriate actions that should betaken can be identified. The equipment for HAZOP studies are:

Reactor (Incubator, Autoclave)

ii.

Distillator ( Distillation still)

iii.

Heat Exchanger ( Heater, Cooler)

iv.

Tanks ( Sulphuric acid storage tank)

Mixer (Autoclave, Incubator)

Detailed HAZOP for each selected unit operation is described below.

295

7.10.7.1 HAZOP Studies on Reactor

The following objectives are suggested on the reactor:

Product quality control - maintain exit composition at specified value

Material balance control - maintain its reaction rate between maximum and minimum limit

Operational constraints - for safe, satisfactory operation of vessel, for instance: -

Reactor pressure should be in range to maintain effective operation.

Temperature difference in reactor should not exceed the critical limit.

Table 7.3: HAZOP Study on Reactor – Reaction Guide

Deviation

Word LESS

Possible

Consequences

Causes Less



reaction

Blockage

Required or 

pipeline leakage  

Overload

Reaction



rate decrease 

Instrumentation failure

Action



Production

Clear blockage.



Check

loss

instrument

Reduce

regularly

production

the



the

Add the pipeline leakage indicator

296

Table 7.4: HAZOP Study on Reactor - Flow Guide Word

Deviation

No flow

Possible Causes  

  LESS

Less flow

 

More flow

 

REVERSE

Consequences

Reverse flow

Low reactor pressure Control valve shut up or pneumatic failure Pipeline leakage or blockage Instrumentation failure Blockage or leakage Instrumentation failure

Action Required

  

No reactions Production loss Furnace running dry



 

Reaction rate  decrease Production  loss

Control valve  fully opened Pressure difference is  too high

Rate of  reaction increase Reactors tube  rupture Deviation in temperature and pressure. Compressor  failure No reaction  Back mixing



Instrumentation failure



Reverse pressure differential.

  

Digital sensor to detect and trace leakage. Install flow sensor and indicator Clear all blockage

Clear the blockage Check the instrument regularly Install feed stream controller. As „NO‟

Install nonreturn valve. Install highpressure alarm.

297

Table 7.5: HAZOP Study on Reactor - Temperature Guide

Deviation

Word

LESS

Possible

Consequences

Action

Causes Low



temperature

Required of 

Failure preheated



Rate

of 

Reaction rate 

Install

decrease

indicator

Loss

water

reactants,

circulation

vented

is too high.

incineration.

Steam

temperature and

controller.

for

line

leakage 

Low steam flow

High



temperature

Failure

of 

cooling 

system 

Hot spots and 

Install

explosions

indicator

Run

temperature and

controller

reaction

and 

Install

circulation

result

the

temperature alarm.

of steam is

formation

too high.

polymers

Rate



high

Catalyst failure

298

Table 7.6: HAZOP Study on Reactor - Pressure Guide

Deviation

Word

LESS

Possible

Consequences

Causes 

Low pressure

 

Action Required

Changes in 

Reaction rate 

Install

action.

decrease

indicator

Valve fully 

Production

controller.

opened

loss.

pressure and

Pipeline leakage

High



pressure

Failure

of 

control valve. 

High



Fire

and 

Install high-pressure

explosions

alarm.

Reactors tube 

Install

rupture.

indicator

temperature

pressure and

controller.

in reactor

7.10.7.2HAZOP Studies on Distillator

Table 7.7: HAZOP Studies onDistillator– Pressure

Guide

Deviation

Word LESS

Possible

Consequences

Causes Less pressure

- Pump failure

Action Required

- Less product

- Change a new pump -

Install

low 299

pressure alarm MORE

More pressure

- As LESS

- Bursting of tube

Install

high

pressure alarm

Table 7.8:HAZOP Studies on Distillatorâ&#x20AC;&#x201C; Temperature Guide

Deviation

Word LESS

Possible

Consequences

Causes No

Action Required

Less

heat -Effect

the - Install low

Temperature

provided/supply

following

temperature

failure

processes

warning device.

More Temperature

- Failure of pump - Heating medium leak into process.

- Pressure will - Install high increase -

Explosion

possibility

temperature warning device - Repair the damage part of heat sterilizer.

300

7.10.7.3 HAZOP Studies on Heat Exchangers Unit

The main objective of the HAZOP study on heat exchanger is maintaining the inlet and outlet temperature of heat exchanger equipment as best as possible to a desired temperature. For safe and satisfactory operation of the heat exchanger, certain constraints must be observed when doing HAZOP. For example, shell and tube pressure drop condition should be high enough to maintain effective process. The analysis is through study of streams: inlet and outlet streams of coolant, steam, and process streams

Table 7.9:HAZOP Study on Heat Exchanger - Flow rate Guide

Possible Deviation

Word

Causes

 Pipe broke  Cooling tower No flow

Action Consequences

not function  Upstream unit failure

Required  Not achieve the desired temperature  Effect further process  Heat build up

 Control valve

in condenser,

 Controller fails and closes valve

valve  Install

flow

indicator  Install temperature

 Pipe plugging

fails closed

 Install a control

may result in explosion

indicator  Install

backup

cooling water  Install backup controller  Install control valve that

100%

fails to open

301

 Valve not

Excess flow

 Same as

functioning

 Install

above

orifice plate

 Product will

or failure to open

 Pipe ruptures

sub

cool state

 Amount of the

 Install

flow

indicator  Change new valve

cold or hot fluid increases  Compressor

REVERSE

 Difficult to

not functioning

Reverse

flow of the  Failure of coolant

control the

upstream

unit  Higher

temperature

flow out.

in  Affect downstream

LESS

Less flow  Control valve of coolant

the

not functioning

control

valve at inlet.  Ensure

the

compressor flowing out

pressure

 Install

 Same as the above

always in good condition and functional  Change a new control valve.

 Flow pipe is plugged

302

Table 7.10:HAZOP Study on Heat Exchanger - Pressure Guide word HIGH

Possible Deviation

Action

Consequences

Required

Cause High

pressure

of coolant flow and hot fluid flow

 Malfunction of compressor  Cold fluid or hot fluid flow pipe plug

 Explosion

 Install

will occur

pressure indicator

 Wall of the

 Install

heat exchanger

pressure

will crack

controller  Check pump 

or compressor

LOW

The

coolant

flow pressure is slow

 Performance of compressor decrease  Rupture at the coolant flow

 Pipe will break and crack

 Same as above  Change new compressor

303

Table 7.11:HAZOP Study on Heat Exchanger - Temperature Guide

Possible

Action

Deviation Word Low temperature

Consequences Causes

Required

 Condensation occurs at  Affect

 Tube of heat

the

tube

heat

exchanger.  Deposition of sediment

LESS

downstream

exchanger should

process

often

at the inner and outer  Failure

cleaned to

tube of heat exchanger,

downstream

remove any

which will prevent heat

process.

deposit

 Steam

 Install

 Reactant will

transfer. utility

service

failure  Leakage

heat

not be heated

temperature

to the desire

indicator  Install

temperature

exchanger tube

controller MORE

High temperature

 Steam utility

 Pressure

service failure  Blockage

increase heat

exchanger tube.  Heat exchanger is not function  Fire at the tube side of the heat Exchanger

will  Install

heater.  Explosion might occur due to high temperature

temperature indicator  Install temperature controller  Regular patrolling and

and pressure

inspection heat exchanger tubes  Repair the

304

damage part of heat exchanger

7.10.7.4: HAZOP Studies on Tanks

The HAZOP study for storage tank involves storage flow parameter. Table 7.12: HAZOP Studies on Storage Tank. Guide

Deviation

Possible Causes

Action Required

Level tank

• Loading more from the • Tank overfills • Install relief valve

Consequences

Word NO

(no flow)

feed line.

possible cause of in the storage tank.

• Reverse flow from the

fire and explosion hazards.

process pump.

• Install high-level alarm.

• Control valve failure.

• Install flow high shut down.

• Line fracture

• Regular check on

• Line blockage

the pipeline valve and pump.

Pressure (more flow)

•

Control

valve

fails • Tank burst if • Regular check on

failure overfills in the valve

continue the pipeline than

tank.

failing.

• Pump failure

• The catalyst will • Install pressure

• Temperature of inlet is

release

the valve.

via relief valve in the

305

hotter

than

normal release valve.

volatile impurities in the feed.

•

tank.

Explosion • Install pressure

hazards

might high

occur.

shut

down

alarm. • Avoid any direct heat to the tank. • Prepare the fire

7.10.7.5 HAZOP Studies on Mixer

Table 7.13: The HAZOP study for mixer is flow rate control. Guide

Deviation

Word NO

Possible

Consequences

Action

causes No flow

Required

 Flow control valve  Mixing failure.  Blockage.

process  Install

cannot be done.  Separation

Less flow

 Same as NO

flow alarm.  Operator

process

cannot

take

achieve

desired

product.

LESS

low

action fix/

change valve

 Less of flow  Same as NO rate

component to mixer/divide. 306

Table 7.14: The HAZOP study for mixer is temperature. Guide

Deviation

Word MORE

Possible

Consequences

causes Higher



temperature

Temperature

Required 

controller failure. 

Valve failed.

Action



High

mixer 

Install

temperature.

temperature

More flow to

alarm.

mixer/

divider 

leads to high

Operators take action

temperature.

7.11

high

Site and Plant Layout

7.11.1 Site Layout

The process units and ancillary building should be arranged to give the most economical flow around the site. Hazardous operations or processes must be located at a safe distance from other buildings and future expansion of the site must be taken into consideration. The ancillary buildings and services are required on a site, in addition to the main processing units will include:

307

a) Storage tank for raw materials and products and warehouse b) Maintenance workshop c) Stores for maintenance and operating supplies d) Laboratories for process control e) Fire station and other emergency services f) Utilities such as cooling tower, power generation, transformer station g) Effluent disposal plant h) Offices for general administration i) Canteens and other amenity building such as medical centers, surau j) Car parks

When roughing out the preliminary site layout, the process unit will be normally be sited first and arranged to give smooth flow of materials through the various processing steps from raw material to final product storage.

The location of the principal ancillary building should be decided. They should be arranged to minimize the time spent by personnel in traveling between buildings. Administration offices and laboratories in which a relatively large number of people will be working should be located well away from potentially danger units, but with potentially hazardous processes may have to be sited at the safety distance. The location of the main building, will determine the layout of plant roads, pipe allays and drains. Access roads are needed at every building for construction and for operation and maintenance. Utility building should be sited to give the most economical run of pipes to and from the process units. The main storage areas should be placed between the loading and the unloading facilities.

308

7.11.2 Plant Layout

The economic construction and efficiency of a process unit will depend on how well the plant and equipment specified on the process flow sheet layout. There are a few factors that have been taken into consideration on the plant layout preparation. Adopting a layout that gives the shortest run of piping connection between unit operations can minimize the cost of construction. However, these procedures will not necessarily be the best arrangement for operation and maintenance.

Equipment that needs to have frequent operator attention should be built conveniently near the control room. Valve, sample points and instruments should be located at convenient positions and heights. Sufficient working space and headroom must be provided to allow easy access to equipment. Heat exchangers need to be sited so that the tube bundles can be easily withdrawn for cleaning and tube replacement. Vessels that required frequent placement of catalysts or packing should be located on the outside of the plant or building. Equipment that requires dismantling for maintenance such as compressors and large pumps should be placed under cover.

Blast wall may be needed to isolate potentially hazardous equipment and confine the effects of an explosion. Process units are normally spaced at least 30 m apart where greater spacing may be needed for hazardous process. The main storage areas should be located between the loading and unloading facilities and the units they served. Storage tanks that contained hazardous materials should be sited at least 70 m from site boundaries.

309

The equipment should be located so that it can be conveniently tied in with any future expansion of process. Space should be left on pipe allays for future needs and service pipe over-sized to allow the future requirements in the process. The arrangement of the major equipment usually follows the sequence given on the process flow sheet. Columns and vessel such as flash vessels are arranged in rows while ancillary equipment such as pumps and heat exchangers are positioned along the outside.

7.12

Consideration of Plant Start-up and Shut Down

Plant start up and shut down is two important elements in operating a plant. This is due to the present of risk and hazards during these two stages. The procedure of the plant start up must be safe and easily, yet flexible enough to be carried out in several ways. During plant start up, the operating limits of the plant must not be exceeded and exposed risk to the employees and public. Sampling, indicators reading are analyzed to determine the stability of the plant, whether it has reach steady stage or not. Control element in this stage is very important, due to the control of flow, temperature and pressure level to the operating ranges.

7.12.1 Plant Start-up

Plant start-up and shut down is two important elements in operating a plant. This is due to the present of risk and hazards during these two stages. The procedure of the 310

plant start-up must be safe and easily, yet flexible enough to be carried out in several ways. During plant start-up, the operating limit of the plant must not be exceeded and exposed risk to the employees and public. Sampling, indicators reading are analyzed to determine the stability of the plant, whether it has reach steady stage or not. Control element in this stage is very important, due to control of flow, temperature, pressure and level of operating ranges (Crowl and Louvar, 1990).

Personnel who take part in this work must be familiar with the process and engineering of the plant, the physical location of equipment and piping. On top of that, laboratory apparatus should to ensure to be in good condition, and calibrated to meet the plant requirements. Sampling point must be clearly identified.

Records for monitoring the plant during start-up must be done. It can be done using the log sheet. A restart-up check of equipment or a system, which is to be started during the initial operation, must be done. The positions of the valves including instrumentation must be verified.

Before plant start-up, the following items must be completed in the processing unit after turnaround of the plant. Below is the start-up procedure that should be followed.

a) Final inspection of the unit operations should be made for conformance to the requirement. b) Turnaround work list is checked again, whether everything has been completed and the associated lines have been correctly resembled.

311

c) All the heat exchangers that were open up to maintenance, must have undergone the hydrostatically test after it has been assembled. d) The instrument control loops are checked from the transmission from the plant signal to control system and also the alarm system circuits to make sure that it has been correctly located. e) All the level gauges glasses are confirmed clear and operator can easily record its reading. f) All the flanges are made sure to have good joints, with good gasket, in order to prevent leakage. g) All the control valves are checked to determine its operability. h) The operability of pumps is checked. i) The operating manual and P & ID are updated with the latest condition of the plant. j) All the utilities, power supply, steam supply and cooling water supply are checked. k) The onsite fire protection equipment such as extinguishers, water hoses, nozzles and steam hoses are in place and ready for immediate use. l) The condition of drains is check to make sure that it is unplugged and water is drained out from the equipment. m) The supply of reactants, catalysts and chemicals are adequate. n) Air freeing and tightness testing are carried out. o) Gas blanketing for certain equipment.

Start-up of a new plant is the most dangerous periods and it will present the most challenge situation to the chemical engineer who exposes their all basic education and experience. High morale is consequently important when this climax of the design and construction effort is reached. Plant start ups are almost inevitably associated with seemingly impossible tasks, as well as frustrating problems and failures. Problems may result from equipment failures, inadequate equipment and process failures. ď&#x201A;ˇ

Equipment failures Include such as leaking, broken shafts and impellers, short circuits and plugged on line. 312



Inadequate equipment Include towers that flood at design capacity. Drivers that are overloaded at rated capacity of the compressor, excessive pressure drop in exchangers and corrosion of equipment inadvertently not supplied according to specifications.



Process failures Generally include those that result from that incorrect use or interpretation of data from the laboratory and pilot plant.

The Important of Start up Steps;

Problems must be avoided strictly when start up a new plant. There are several guidelines on how the chemical engineers can start-up their new plant:



Organize - the various groups, crafts and technical personnel who will participate in the commissioning and the necessary information.



Prepare the detailed plans, schedules and budgets.



Train the personnel.



Perform - the pressure tests, the dry runs, the hot tests, the dynamic safe-fluid tests, the dynamic solvent tests, the process-fluid tests.



Operate the plant to make product.



Trouble shoots and makes performance analysis.



Maintain the plant and make modifications.

7.12.2 Plant Shut Down

313

There are three types of plant shutdown, the normal shutdown for turnaround, emergency shutdown, tripped by the interlock system due to the danger imposed by the failure of the plant and result an automatic shutdown (Crowl and Louvar, 1990).

This plant shutdown procedure covers the shutdown of the entire unit for major repair work such as a turnaround, which could take several weeks. If a short shutdown of a couple days is required, the procedure can be cut short at the appropriate point.

Pressure on equipment can be released, directing the vapors to the incineration or sent it to storage tank, after all liquids have been drained to the blow down system. If the shutdown is of partial or temporary nature, a great deal of expense, unnecessary incineration and time can be saved by putting every columns onto total reflux, shutting off the overhead and bottom product flows, providing that the overhead condenser coolant and reboiler heating medium remain available.

Pumps should be shutdown before the supply of liquid to the suction falls. However, level may rebuild and temporary pump re-commissioning may be necessary. For the reason, pumps should not be isolated and vented or drained prematurely.

During the shutdown, all the equipment must be left in a safe condition. When inspection or repair is to be carried out on a vessel or column, it should be blinded and thoroughly purged with steam, depending on the service. Care must be taken not to steam out piping or vessels covered with low temperature insulation. If low temperature equipment is steamed out for a special reason, it will need to be re-dried before recommissioning. The thing to be considered for shutdown is listed as below: 314

a) The turnaround work list is prepared to include all the items for repair, cleaning, inspection and modification. b) The detailed plan of the shutdown and turnaround schedule should be prepared, probably hour-by-hour schedule.

The following item must be checked, before shutting down the plant (Crowl and Louvar, 1990):

The fire fighting equipment is located correctly a) The personal protective equipment is available for immediate use. b) All special precaution that is specific for the shutdown are taken attention, for example hoses laid at the important place for immediate use. c) All items that are needed during shutdown are prepared. These include blinds, hoses, etc. d) Advanced preparation work is carried out prior to the shutdown of the unit, to avoid any delay in mechanical work during the actual shutdown, for example the erection of scaffolding.

The shutdown procedures are as below:

Cooling and Depressuring the Unit

The first step in shut down of plant operation is to gradually reduce the heat supply to each unit and finally cut off. Then the temperature of the material should be lowered to the point at which vaporization stop. The decreased in vaporization soon 315

renders the overhead and side streams systems inactive and permits them to be shutdown. Releasing gases to a gas collecting system should relieve excess pressure. If the cooling tends to procedure a vacuum in the unit, an inert gas should be reduced to maintain the pressure close to atmospheric pressure. An inert gas prevents fires or explosions in the unit. Air must not be introduced.

Pumping Out the Unit

Each material should be pumped to prescribed place. Centrifugal pumps should be watched carefully to make sure that completely none loses suction before it is shut down. Running a centrifugal pump dry even a short time may seriously damage it. If available, reciprocating pumps are the best for pump out because they have superior suction characteristics and are less susceptible to damage.

As the materials are pumped from the unit, it should be further cooled in heat exchange equipment to a temperature where it will not caused flashing of water in delivery lines or tanks and to a temperature below its flash point so it will not caused fire hazards in the delivery tanks. Inert gas should be admitted to the unit continuously during pump out operation for two reasons: to prevent entrance of air into the unit close to atmospheric pressure and thus prevent collapse of any equipment not designed to withstand sub atmospheric pressures.

Removal of Residue

316

The unit should be purged of residual. Removal of this material can be done in three major ways: displacement with inert gas, water flooding to overflowing and a combination of these two methods. The type of unit determines the appropriate purging material.

7.12.3 Unplanned Shut-Down

An unplanned shut down initiated by a power outage, compressor trip or shut down caused by the automatic shut down system employed in the process. There are two types of automatic shut down systems:

ď&#x201A;ˇ

Individual devices such as high pressure difference switch our reactor to detect flow distributor clogging.

ď&#x201A;ˇ

A general device such as high pressure switches on main cooling water headers.

This plant shut down is actuated by signal from so voting system, during emergency situation. This system consisting of three instruments on each potential cause of general shut down indicates presence of the relative cause only when the system detects any failure.

After a general shut down is trigged by the shut down system, the plant can operate safely and quickly after the emergency. When the system has been carefully

317

designed and cabling in properly sheathed, the general shut down system is the safest, dependable and economical addition to a plant.

7.12.4 Emergency Shutdown

If an emergency incident happened in the operation plant, the process must be returned to a safe condition. A special plant protection control system, otherwise known as process trip system or an emergency shutdown system, is designed to handle the effect the emergency shutdown of the plant when this becomes necessary. It carries out the appropriate activities on command either from push-button when passed by an operator from automatic activation of the relay. Such systems are closely associated with the shutdown of a plant when some units remain on hot stand-by. If plant kept partially working in this manner, then time is saved during the start-up of the plant, and hazard such as ingress of air may be avoided. Sometimes a lack of time and the need for the action prevent the decisions regarding hot-stand-by being made by the management, and the initial is determined automatically by the trip system in the plant (Crowl and Louvar, 1990). Usually the emergency condition on the operation units are caused by the following conditions:

a) Loss of utility such as cooling water, electricity, steam and etc. b) Mechanical failure of equipment, which prevents normal operation or result in a serious fire or leak (Md. Wijayannuddin, 2004).

318

Following are the steps to be taken in the event of emergency:

a) Determine the extent of the emergency condition b) Decide how to overcome the emergency condition i)

Handle the emergency as localized condition without shutting down the whole plant or unit

ii)

Shut down the unit using the emergency practice and procedure. [9]

Special Safety Consideration: Protection of Equipment a) During the initial start-up, all the lines will be water washed to remove debris. Before any rotating equipment is started, ensure that the pumps have the proper suction strainers installed. b) Before starting, always purge all air or vapor out of pump. Fill the pump completely with liquid. c) When draining equipment of liquid, ensure that equipment is depressurized or has an unobstructed vent open to prevent a vacuum. d) When commissioning the steam system, it should be done slowly to prevent water hammer. The cold lines can cause condensation of some steam and if the steam is allowed to enter the system at high velocity, the resulting water hammer can cause distortion and even rupture of equipment. e) When any alarm in the processing unit is ON, response for this abnormality must be done immediately to prevent the upset conditions and equipment damage. f) While steam purging equipment, never shut-off the steam with the equipment vents closed since this will resulting the condensation of the steam and will produce a vacuum in the equipment which can cause serious damage. [8]

319

7.12.5 Start-up and Shutdown for Major Equipment

Start-up and shutdown must be done with intention to the possible effects of shocking a pressure vessel system by rapid pressure or temperature changes. Most vessel manufacturers provide detailed instructions for starting and shutting down their equipment and process engineers should supplement these with specific instruction for the process involve. Thermal socking can be avoided by slow, uniform heating and cooling of vessel system.

Large, thick rotating vessel, for example, should be rotated slowly, and if they are steam-heated, steam should be admitted to the vessel in a controller manner to avoid thermal stress being set up between thin and thick sections, which may not expand at the same arte. The same precautions must be used in shutting down. The rotating pressure vessel should be kept rotating after the heat source has been removed in order to maintain uniform temperature throughout the vessel while it is cooling. Because of the variety of pressure vessel, careful planning and training may be necessary in order to avoid shocking a system when starting or shutting down a process line. Typical of such instruction is the following for heat exchangers, as developed by American Standard for their equipment:

a) Be sure the entire system is clean before starting the operation in order to prevent plugging of tubes or shell-side passages with refuse. The use of strainers or settling tanks in pipelines leading to the heat exchanger is recommended. b) Open vent connections before the starting up. c) Start operating gradually. If in doubt, consult the manufacturer.

320

d) After the system is completely filled with the operating fluid and all air has been vented, close all manual vent connections. e) Retighten bolting on all gaskets or packed joints after the heat exchanger has reached operating temperatures to prevent leaks and gasket failure. f) Do not operate the heat exchanger under pressure and temperature conditions in excess of those specified on the nameplate. g) To guard against water hammer, drain condensate from steam-heated exchanger and similar apparatus, both when starting up and shutting down. h) Drain all fluids when shutting down to eliminate possible freezing and corrosion. i) In all installations, avoid pulsation of fluids, since this causes vibration and will result in reduced operating life. j) Do not under circumstances operate the heat exchanger at flow rate greater than that shown on the design specifications. Excessive flow can cause vibration and severely damage the heat exchanger tube bundle. k) Protect heat exchangers that are out of service for extended period of time against corrosion. Heat exchangers that are out of service for short periods and use water as the following medium should be thoroughly drained and blown dry with warm air if possible. If this is not practical, water should be circulated through the heat exchanger on a daily basis to prevent stagnant water conditions that can ultimately precipitate corrosion.

7.12.6 Clearance for Maintenance

Large pressure vessels require special consideration for maintenance needs. All pressure vessels should be installed with sufficient clearance to allow inspection and maintenance to be done without having to disturb adjacent equipment. Ample space should be provided for the removal of covers and shells or bundles of tubes, and for the 321

retightening and, if needed, repair welding of joints. For the large vessels, clearance should be provided so that cranes or hoists can be used to service the vessel (Md. Wijayannuddin, 2004).

322

CHAPTER 8

MECHANICAL DESIGN OF MAJOR EQUIPMENT

8.1

Introduction

A chemical engineer is normally required to specify the main dimensions of the pieces of equipment of which he/she is responsible. Mechanical design involves calculation dealing with the construction of a whole unit, in order to allow fabrication and erection to proceed. The process chemical engineer should be sufficiently aware of the problems and design method involved to ensure that the calculation do not produce unduly difficulties and expensive problems in the later stage.

The detail mechanical design work of the pressure vessel is supposedly to be carried by the mechanical engineers. However, this section is to develop and specify the 323

basic design information for a particular vessel which is very useful for the pressure vessel design work done by mechanical engineers later on. All the detailed calculations for the process vessel are shown in Appendix D.

8.2

Equipment Specification Sheet

Equipment specifications sheet are summaries of the sizing of the major and auxiliary equipments of the plant. All the parameters calculated from the material and energy balances, equipment costing and mechanical sizing should be included. These are the most important task for design engineers since this information provide the suppliers the overview of all the equipment needed for the newly developed process plant. The equipments that are presented under this chapter are specification sheets of: 1. Autoclave 2. Extraction unit 3. Incubator 4. Condenser

8.3

Mechanical Design of Autoclave

The example of mechanical design for autoclave, V-102 is shown in Appendix D. The mechanical drawing shown in Figure 8.1.The summary of mechanical design for V-102 is tabulated in Table 8.1 as follows: 324

Table 8.1: Mechanical Design Summary for Autoclave, V-102 EQUIPMENT SPECIFICATION SHEET Identification : Autoclave Item No

: V-102

Function

: Mix the solution and sterilize

SPECIFICATION Design type

Vertical

Material of construction

Stainless Steel 316

Operating temperature

121 oC

Operating pressure

15 bar

Vessel volume

4.5 m3

Vessel length

4.508 m

Vessel diameter

1.127 m3

Wall thickness

0.0146 m

Inside diameter

1.098 m

MECHANICAL DESIGN Type of insulation

Mineral Wool

Domed head type

Ellipsoidal head

Average insulation thickness, ti

0.075 mm

Weight of insulation, Wi

1517.61 N

Total weight, W

25917.61 N

Wind loading, Mx

16715.47 Nm

Number of bolts, Nb

325

Scale: Not to scale Title: Autoclave

Date: 25th May 2013

Figure 8.1: Mechanical Drawing of Autoclave

326

8.4

Mechanical Design of Extraction unit

The example of mechanical design for extraction unit, V-104 is shown in Appendix D. The mechanical drawing is shown in Figure 8.2. The summary of mechanical design for V-104 is tabulated in Table 8.2 as follows:

Table 8.2: Mechanical Design Summary for Extractor Vessel, V-104 EQUIPMENT SPECIFICATION SHEET Identification : Extractor Vessel Item No

: V-104

Function

: Separate product from the mixture

SPECIFICATION Design type

Vertical

Material of construction

Stainless Steel 316

Operating temperature

327 oC

Operating pressure

1 atm

Vessel volume

4.3 m3

Vessel length

4.4 m

Vessel diameter

1.1 m3

Wall thickness

0.0144 m

MECHANICAL DESIGN Material of construction

Stainless steel 316

Type of insulation

Mineral Wool

Domed head type

Ellipsoidal head

Average insulation thickness, ti

0.075 mm

327

Weight of insulation, Wi

1479.35 N

Total weight, W

22379.35 N

Wind loading, Mx

1594.97 Nm

Number of bolts, Nb

Scale: Not to scale Title: Extraction unit

Date: 25th May 2013

Figure 8.2: Mechanical Drawing of Extraction unit

328

8.5

Mechanical Design of Incubator

The example of mechanical design for incubator is shown in Appendix D. The mechanical drawings are shown in Figure 8.3 respectively. The summary of mechanical design for V-103istabulated in Table 8.3 as follows:

Table 8.3: Mechanical Design Summary for Incubator Tank, V-103 EQUIPMENT SPECIFICATION SHEET Identification : Incubator Item No Function

: V-103 : Incubate mixture at constant temperature

SPECIFICATION Design type

Vertical

Material of construction

Stainless steel 316

Type of agitator

Turbine

Agitator speed

50 rpm

Vessel volume

5 m3

Vessel diameter

1.168 m

Vessel length

4.672 m

Wall thickness

0.0152 m

Horse power (Hp)

8.269

Residence time

30 min

Operating temperature

55 oC

Operating pressure

1 atm

329

MECHANICAL DESIGN Day of inventory

3 days

Volume stored

4.5 m3

Meridian tank stress

3 842 105.26N/m2

Tangential stress

1 921 052.63 N/m2

330

Scale: Not to scale Title: Incubator

Date: 25th May 2013

Figure 8.3: Mechanical Drawing of Incubator

331

8.6

Mechanical Design of Condenser

Detailed calculations for the mechanical design of the condenser is listed in Appendix D. Mechanical specification of the condenser is summarized in tables below.

Table 8.4: Mechanical design specification sheet of condenser, HX-102 EQUIPMENT SPECIFICATION SHEET Identification : Heat Exchanger Item No : HX-102 Function : Change vapor phase to liquid phase SPECIFICATION Type of heat exchanger

Shell and tubes, 1 shell : 2 tube passes

Material of construction

Carbon steel

Design type

Floating head

Outer diameter, Dto

19.05 mm

Inner diameter, Dti

15.75 mm

Length of tube, Lt

4.88 m

BWG number

OPERATING CONDITION Heat duty

161 256 699.1 kW

Hot fluid inlet temperature (T1)

327 째C

Hot fluid outlet temperature (T2)

25 째C

Cold fluid inlet temperature (t1)

20 째C

Cold fluid outlet temperature (t2)

86.19 째C

Heat transfer area

1.98 m2

332

Height (baffle chord to top of tube bundle)

4.055 x 10-3

Angle subtended by the baffle chord

118.8733째

Number of tubes in the window zone

Number of tube rows in window zone

Number of tubes in cross-flow zone

Window zones area

8.75 x 10-4 m2

Number of tube rows in window zone area

Baffle cut height

9.055 x 10-3m

Tube-to-baffle clearance area

1.2 x 10-4m2

Baffle-to-shell clearance area

0.0175 m2

Baffle diameter

0.08735 m2

Baffle cut area

8.15 x 10-4m2

333

Scale: Not to scale Title: Condenser

Date: 25th May 2013

Figure 8.4: Mechanical Drawing of condenser

334

Appendix D

Mechanical Design for Autoclave

Design Pressure For safety purpose, the design pressure will operate 10% above the operating pressure was chosen.

(15 â&#x20AC;&#x201C; 1) x 1.1

15.4 bar

1.54 N/mm2

Design stress, f

135 N/mm2 at temperature 300oC

Tensile strength

520 N/mm2

Material used

Welded joint efficiency J

Corrosion allowance Minimum corrosion =

2 mm

335

Cylindrical wall thickness Minimum wall thickness: 14.6 mm Section 1

14.6 mm

Section 2

16.6 mm

Section 3

18.6 mm

Section 4

20.6 mm

Section 5

22.6 mm

Average thickness

18.6 mm

Design of domed heads Try a standard dished head (torisphere): Crown radius, Rc = Di = 1.098 m Knuckle radius, Rk = 0.06Rc = 0.066 m A head of this size would be formed by pressing: no joint, so J = 1

1  Rc  3  4  Rk 

1 1.098m 4 0.066m

1.02

Pi Rc C s 2 fJ  Pi C  0.2 336

1.54 N / mm 2  1.098  10 3 mm  1.02 2(110 N / mm 2 )  1.54 N / mm 2 (1.02  0.2)

7.795 mm

Try standard ellipsoidal head, ratio major : minor axes = 2 : 1 e

Pi Di 2 Jf  0.2 Pi

1.54 N / mm 2  1.098  10 3 mm 2(110 N / mm 2 )  0.2(1.54 N / mm 2 )

7.696 mm

So, an ellipsoidal head would probably the most economical. Head thickness

7.696 mm + 2 mm

9.696 mm

Weight loads

Refer Chapter 8 – Mechanical Design W = ( Di + ts)( L + 0.8 Di) ts ρ W = (46 + 0.598)(184 + 0.8(46))(0.598×0.284) W = 5489.54 lb = 24.4 kN

337

Weight load of insulation material

Insulation is needed mainly because of safety reason. The insulation weight is calculated as shown in the following section. Mineral wool is chosen as the insulation material.

The thickness of insulation, ti =

75 mm

Density of mineral wool

130 kg/m3

Volume of insulation, V

ď °DmtiHv

3.142 x 1.12 x 0.075m x 4.508

1.19 m3

ď ˛materialVmaterial g

1517.61 N

Weight of insulation, Wi

From (Sinnott, 1983), it is stated that this value should be doubled for fittings, sealing and moisture absorption etc. So, total weight of insulation is

Total weight, W

Wv + Wi

24.4 x 103 + 1517.61 N

25917.61 N 338

Wind loading Take dynamic wind pressure, Pw as 1280 N/m2 (Sinnott, 1983) Pw

1280 N/m2

Deff

Di + 2 (t + ti x 10-3)

1.2852 m

PwDeff

1280 N/m2 x 1.2852 m

1645.056 N/m

Loading per unit length, Fw

Bonding moment at bottom tangent line, Mx Mx

Fw H 2 2

1645.056 ď&#x201A;´ 4.508 2 2

16715.47 Nm

PDi / 2t

61.537 N/mm2

Analysis of stresses At bottom tangent line Pressure stresses ď łh

339

L

PDi / 4t

30.769 N/mm2

Wv  ( Di  t )t

0.508 N/mm2

Di + 2t

1098 + 2 (13.739)

1125.48 mm

Dead weight stress w

Bending stresses Do

Second moment of area of the vessel about the plane of bending Iv

b

(/ 64) (Do4 – Di4)

7.84 x 109

M  D    x    i  t    Iv   2

121.02 N/mm2

Baffles It was decided that four diametrically opposed baffles would be put in the vessel. The size of each baffle should be 0.1- 0.05 tank diameter. The assumption: 340

Df = 0.1 x DT = 0.1 x 1.098 = 0. 1098

Design of vessel support

Determining the vessel support: Vessel support is very important because it is like foundation of a building. When determining the support of the vessel, many factors have to be taken into consideration like size, shape and weight of the vessel. Generally, there are 3 types of support; saddle support, skirt support and brackets support. Saddle support is for horizontal vessel. Whereas skirt support is for vertical vessel and brackets can be used for either type of vessel. For flash drum, we will be using skirt support because it will be placed vertically. Skirt support consists of a cylindrical on conical shell welded to the base of the vessel. The material for the skirt will be plain stainless steel. The data needed can be obtained from Table 13.2 (Sinnott, 1983) as follows: Design stress

110 N/mm2

Young Modulus, E

179959.5 N/mm2

1.098 m

Maximum weight load will occur when the reactor column is fully filled with liquid. Therefore, the maximum design weight for the skirt will be based on this condition. Density of liquid

1000 kg/m3 341

The approximate weight when maximum weight load: Approximate weight

Total weight of vessel, Wt

(ď °/4)Di2Hvď ˛liquid

4268.53 kg

41900 N

25917.61 + 41900 N

67817.61 N

Mechanical Design for Extraction unit

Design Pressure For safety purpose, the design pressure will operate 10% above the operating pressure was chosen.

1.01325 x 1.1

1.114575 bar

0.11 N/mm2

Design stress, f

135 N/mm2 at temperature 300oC

Tensile strength

520 N/mm2

Material used

342

Welded joint efficiency J

Corrosion allowance Minimum corrosion =

2 mm

Cylindrical wall thickness Minimum wall thickness: 14.4 mm

A much thickness wall will be needed at the column base to withstand the wind and dead weight loads. For the first trial, divide the column into5 sections with thickness increasing by 2.00 mm per section.

Section 1

14.4 mm

Section 2

16.4 mm

Section 3

18.4 mm

Section 4

20.4 mm

Section 5

22.4 mm

Average thickness

18.4 mm

343

Design of domed heads

Try a standard dished head (torisphere): Crown radius, Rc = Di = 1.11 m Knuckle radius, Rk = 0.06Rc = 0.067 m A head of this size would be formed by pressing: no joint, so J = 1

1  Rc  3  4  Rk 

1 4

1.018

1.11m 0.067m

Pi Rc C s 2 fJ  Pi C  0.2

6.49 N / mm 2 1.1110 3 mm 1.018 2(110 N / mm 2 )  6.49 N / mm 2 (1.018  0.2)

32.94 mm

Try standard ellipsoidal head, ratio major : minor axes = 2 : 1 e

Pi Di 2 Jf  0.2 Pi

6.49 N / mm 2 1.1110 3 mm 2(110 N / mm 2 )  0.2(6.49 N / mm 2 )

32.55 mm 344

So, an ellipsoidal head would probably the most economical. Head thickness

32.55 mm + 2 mm

34.55 mm

Weight loads

Weight load of vessel shell Then, with 2:1 elliptical heads, the approximate weight of a cylindrical vessel with domed ends and uniform wall thickness, can be estimated from the following equation: W = ( Di + ts)( L + 0.8 Di) ts Ď W = (43.7 + 0.567)(175 + 0.8(43.7))(0.567Ă&#x2014;0.284) Wv= 4 701.84 lb = 20.9 kN

Weight load of insulation material

Insulation is needed mainly because of safety reason. The insulation weight is calculated as shown in the following section. Mineral wool is chosen as the insulation material.

The thickness of insulation, ti =

75 mm

345

Density of mineral wool

130 kg/m3

Volume of insulation, V

ď °DmtiHv

3.142 x 1.12 x 0.075m x 4.4

1.16 m3

ď ˛materialVmaterial g

1479.35 N

Weight of insulation, Wi

From (Sinnott, 1983), it is stated that this value should be doubled for fittings, sealing and moisture absorption etc. So, total weight of insulation is

Total weight, W

Wv + Wi

20.9 x 103 + 1479.35 N

22379.35 N

Wind loading Take dynamic wind pressure, Pw as 1280 N/m2 (Sinnott, 1983) Pw

1280 N/m2

Deff

Di + 2 (t + ti x 10-3)

1.2868 m

346

Loading per unit length, Fw

PwDeff

1280 N/m2 x 1.2868 m

1647.104 N/m

Bonding moment at bottom tangent line, Mx Mx

Fw H 2 2

1647.104  4.4 2 2

15943.97 Nm

PDi / 2t

3.29 N/mm2

PDi / 4t

1.64 N/mm2

Analysis of stresses At bottom tangent line Pressure stresses h

L

347

Dead weight stress w

Wv  ( Di  t )t

3.23 N/mm2

Di + 2t

1100 + 2 (18.4)

1136.8 mm

Bending stresses Do

Second moment of area of the vessel about the plane of bending Iv

b

(/ 64) (Do4 – Di4)

1.01 x 1010

M  D    x    i  t    Iv   2

2.90 N/mm2

Baffles It was decided that four diametrically opposed baffles would be put in the vessel. The size of each baffle should be 0.1- 0.05 tank diameter. The assumption: Df = 0.1 x DT = 0.1 x 1.1 = 0. 11 348

Design of vessel support

110 N/mm2

Young Modulus, E

179959.5 N/mm2

1.1 m

Maximum weight load will occur when the reactor column is fully filled with liquid. Therefore, the maximum design weight for the skirt will be based on this condition. Density of liquid

1000 kg/m3

The approximate weight when maximum weight load: Approximate weight

(ď °/4)Di2Hvď ˛liquid

538.84 kg

528.00 N 349

Total weight of vessel, Wt

22907.35 N

Determining number of bolts

The following assumptions have been made and taken from (Sinnott, 1983): Pitch circle diameter

2.2 m

Circumference of bolts circle =

2200

Bolt design stresses, fb

125 N/mm2

Minimum bolt pitch

600 mm

Min number of bolts required =

2200/600

11.5207

≈

12 bolts

Mechanical design for Incubator

Storage Classification

Vertical Cylinder Tank

Material of Construction

Stainless Steel 316

Volume Stored (m3)

4.5 m3

Day of Inventory

2 days

350

From the sizing calculation:

Diameter of tank: D = 1.168 m Height of tank H = 4.672 m

Stress of Tank

From equation 13.63 & 13.64 in Chemical Engineering, R.K. Sinnot,

h 

PDi 2t

L 

PDi 4t

= 1 atm = 100 000 N/m2

Where, h = the meridian (longitudinal), the stress acting along a meridian L = the circumferential or tangential stress, the stress acting along parallel circles t = thickness of cylinder P = pressure 351

Table 8.5: Minimum Shell Wall Thickness Nominal Tank Diameter

Minimum Shell Plate Thickness, in

D < 50

3/16

50 < D< 120

1/4

120 < D < 200

5/16

D > 200

3/8

From the table above, the minimum wall thickness is 3/16 in = 4.76 mm

 5 mm = 0.005 m.

From the sizing of the incubator tank, it was calculated that the thickness of the shell is 1.52 cm after considering corrosion allowance.

h = PDi/2t = (100 000 N/m2 x 1.168 m)/ 2(0.0152 m)

= 3 842 105.26 N/m2 L = PDi/4t = (100 000 N/m2 x 1.168 m)/ 4(0.0152 m)

= 1 921 052.63 N/m2 352

Mechanical design for Condenser

Bundle diameter, Db = 0.08055m Shell inside diameter, Ds = 0.09055 m Number of tube, Nt = 6 Pitch, pt = 0.0238125 m Tube outside diameter, Dto = 0.01905 m Baffle spacing, lB = 0.08895 m

Height from the baffle chord to the top of the tube bundle, Hb 

Db  Ds (0.5  Bc ) 2

= 4.055 x 10-3 m

Baffle geometrical factor (bundle cut), Bb=

Hb Db

= 0.0503

Assume R‟a (ratio of the bundle cross-sectional area in the window zone to the total bundle cross-sectional area) 0.18 and b (angle subtended by the baffle chord) 2.075 rad = 118.8733.

353

The number of tubes in the window zone Nw = NtR‟a = 6  0.18 = 1.08  1 tube For equilateral triangular pitch, p‟t = 0.87pt = 0.87  0.0238125 m = 0.020717 m Number of tube rows in window zone, Nwv =

Hb p ,t

= 4.055 x 10-3 /0.020717 = 0.1957  1 row The number of tubes in cross-flow zone, Nc = Nt – 2 Nw = 6 – 2 (1) = 4 tubes

Ratio number of tubes in window zones to total number, Rw =

2 Nw Nt

= 0.3333

354

 Ds2   N wDto2    Ra    Window zones area, Aw =   4   4  = 8.75 x 10-4 m2 Number of tube rows in this zone, Ncv =

( D b  2H b ) p ,t

= 3.5  4 rows Baffle cut height, Hc = DsBc = 0.09055 m  0.10 = 9.055 x 10-3 m

Assume the tube-to-baffle clearance, ct = 0.8 mm = 810-4 m. Tube-to-baffle clearance area, Atb =

c t D to N t  N w  2

= 1.2 x 10-4 m2

And also assume the baffle-to-shell clearance, cs = 1.6 mm = 1.610-3 m. Baffle-to-shell clearance area, Asb =

c s Ds 2   b  2

= 0.0175 m2 Small spacing allowable between tube-to-baffle and shell-to-baffle since the baffle diameter, 355

Dc = Ds – 2(cs) = 0.09055 m – 2(1.610-3 m) = 0.08735 m

Thus, baffle cut area, Ab = lB (Ds - Db) = 0.0815 m (0.09055 m – 0.08055 m) = 8.15 x 10-4 m2.

356

CHAPTER 9

PROFITABILITY ANALYSIS

9.1

Introduction

This chapter will use economy analysis in order to determine the profit margin. The analysis comprises of the fixed capital cost and manufacturing cost. Manufacturing cost is the cumulative total of resources that are directly used in the process of making various goods and products. It is also the cost that most provided by the investor in order production can be functioned. After done cost estimation, cash flow analysis will be carried out to give the overall economic feasibility of the plant and to find out the payback period that very concerned by the investors. In this chapter, it will considered about an overall profitability based on estimating fixed capital investment, total capital investment, total production cost and revenue from sales and others need to take consideration.

The cost calculated in this chapter is as followed: 

Bare module cost (including equipment cost, direct and indirect cost)



Total production cost



Cash flow analysis

357

9.2

Gross Root Capital

In order to determine the gross root capital for essential oil of Gaharu plant, all the costing of equipment used for this plant from previous chapter were needed for the calculation. Gross-root capital cost was covering the major portion of total fixed capital cost. Gross-root capital cost was defined as the cost of equipment installed in a plant. Bare Module method was used to estimate the cost of equipment used in our plant. To calculate the GRC, contingency and fees (8% of bare module cost), and auxiliary facilities (10% of bare module cost) were added to the initial bare module cost.

358

Table 9.1: Capital Cost Summary Bare Module Cost for Equipment Equipment

Unit

Cost per unit (RM)

Cost Total (RM)

Grinder

33 000

Mixing tank

80 472.59

Storage Tank

17 853.83

Autoclave

473 488.12

Incubator

158 421.92

475 265.76

Oil and water separator

110 398.25

Extraction unit

109 835. 63

Pump

109 954.83

Cooler

178 807.65

Condenser

144 910.95

Boiler

110 398.25

Equalization tank

434 076.66

Aeration tank

64 478.05

Clarifier

35 255.07

Pump 1

2 207.54

Pump 2

2 374.48

Pump 3

2 597.98

Pump 4

2 207.54

Filter press

57 000

1 361.75

Waste Water Treatment

Sludge disposal Total Bare Module Cost, TBM Contingency and fee, 8% TBM

2 445 944.33 2 445 944.33 x 0.08

Total Module Cost, TMC Auxiliary Facilities, 10% TBM Grass-roots capital (GRC)

195 675.55 2 641 619.88

2 445 944.33 x 0.10

244 594.43 2 886 214.31 359

9.3

Fixed and Total Capital Investment Cost

Fixed capital investment (FCI) represent the total cost for installed the process equipment with all auxiliaries that are needed for complete the operation of the process. It includes the direct cost and indirect cost for the set up of the plant. For capital investment (TCI):

Total Capital Investment = Fixed Capital Investment + Working capital + Start Up Cost

The estimation of capital investment cost can be calculated by considering five factors which are:

a) Direct cost b) Indirect cost c) Fixed-capital investment d) Working capital e) Total capital investment

Working capital was defined as the difference between current assets and current liabilities. Current assets are the most liquid of company assets, meaning they are cash or can be quickly converted to cash. Current liabilities are any obligations due within one year. Working capital measures what is leftover once current liabilities was subtracted from the current assets, and can be a positive or 360

negative amount. The working capital is available to pay company current debts, and represents the cushion or margin of protection that can give short-term creditors.

The working capital is the additional investment needed to start up the plant and operate to its point when income is earned. Working cost is usually will be recovered at the end of the plant. Working capital consists of the total amount of money invested in raw materials and supplies carried in stock, finished products in stock and semi-finished products in the process of being manufactured, account receivable, cash kept on hand for monthly payment of operating expenses. Mostly chemical plant uses about 10% of the fixed capital investment whereas start up cost is 7% out of fixed capital cost as an initial working capital.

361

Table 9.2: Total Fixed Capital and Total Capital Investment

Specification Direct Cost Onsite Purchased Equipment Installation Instrumentation and Control (installed)

Cost (RM)

10 % GRC

288 621.43

5 % GRC

144 310.72

Piping (installed)

10 % GRC

288 621.43

Electrical and Material (installed)

5 % GRC

144 310.72

Offsite Building

10 % GRC

288 621.43

Yard Improvements

2 % GRC

57 724.29

Service Facilities Land

2 % GRC 3 % GRC Total 1

Indirect Cost Engineering and supervision Construction Expenses Contractorâ&#x20AC;&#x;s Fee Contingency

2 % GRC 3 % GRC 1 % GRC 5 % GRC Total 2

Total

= Total 1 + Total 2

57 724.29 86 586.43 28 862.14 144 310.72 317 483.58 1 674 004.32

Fix Capital Investment (FCI) Working Capital Start Up Cost Total Capital Investment (TCI)

57 724.29 86 586.43 1 356 520.74

4 560 218.63 10 % FCI 8 % FCI

456 021.86 364 817.49 5 381 057.98

362

The plant capital investment that already been calculated were including all equipments cost, waste treatment cost, the direct cost in setting up the plant, indirect cost and also cost for working and start up cost. The total capital investment of RM 5 304 150.93 was needed where the calculations are tabulated in the Table 9.2.

9.4

Manufacturing Cost

Manufacturing cost is an important aspect of plant economics. Manufacturing cost consists of direct manufacturing expenses, indirect manufacturing expenses and general expenses. As an example was operating labor cost, utilities cost, administration cost, maintenance cost, tax patents, royalties and other cost. The operating hour per year of this plant is 2864 hours with 8-hour operation. The operation day is 358 days per year.

9.4.1

Estimation of Operating Labor Cost

Table 9.3: Operating labor estimation

Equipment

No. of

Operator per unit per

Operators per shift

unit

shift

Grinder

0.2

Mixer

0.2

Storage Tank

Autoclave

0.2

Cooler

0.2

Pump

363

Incubator

0.5

Extractor

0.5

Condenser

0.2

Boiler

0.5

Oil water separator

0.5

Total

From the table, Number of labor (operator)

= 3.0 per shift = 3 persons /day

Besides, Number of supervisor (engineer)

= 2 person/day

Human Resource staff

= 2 persons/day

Security Guards

= 2 persons/day

Others

= 1 persons/day

Operator salary

= RM 1 000/month

Engineer salary

= RM 3 000/month

HR staff salary

= RM 2 000/month

Security Guard salary

= RM 1 000/month

Others salary

= RM 800/month

Total labor cost

= RM 15 800/month = RM 189 600/year

9.4.2

Estimation of Utilities Cost

a. Electricity cost

Price per unit

= RM 0.1647 / kW hr (Based on Tariff E-3)

Equipments duty

= 3 705 kW

Others

= 1.0 kW

364

Annual Utilities costs for electricity, Ae

= (3 710 kW) x (RM 0.1647 / kW hr) x (2 864 hr/1year) = RM 1 750 009.97

b. Water cost

Price per unit

= RM 2.22 / m3

Equipment

= 273.1 m3/ hr

Others

= 2 m3/ hr

Recycle

= 100 m3/hr

Annual Utilities costs for water AW

= (273.1+2-100 m3/ hr) x (RM 2.22 / m3) x (2864 hr /1year) = RM 1 113 299.81

Manufacturing Cost Summary

Fixed capital, FCI

= RM 4 560 218.63

Working capital (10% of fixed capital), CWC

= RM 456 021.86

Start Up Cost (8 % FCI)

= RM 364 817.49

Total capital investment, TCI

= RM 5 381 057.98

365

Table 9.4: Manufacturing Cost Summary

Specification

Cost

RM/yr.

Manufacturing Expenses Direct Production Cost

RM/yr.

Raw material Gaharu chip

RM 15.00 /kg

6 444 000

50 % H2SO4

RM 30.00 /kg

1 159 920

Na2SO4 flakes

RM 5.00/kg

78 760

Enzyme

RM 50.00/kg

64 440

Utilities Electricity

RM 0.1647/kW h

3 056 827.40

Water

RM1.05/m3

2 332 143.74

Maintenance and repairs Operating supplies

5% FCI

228 010.93

0.2% FCI

9 120.44

10 persons/day

189 600

10% Operating Labor

18 960

Laboratory charges

15% Operating Labor

28 440

Plant Overhead

50% Operating Labor

94 800

Operating Labor Direct Supervision & Clerical Labor

Indirect Production Cost

Rates (Local authority taxes) Insurance Total Manufacturing Expenses, AME

0.5% FCI

22 801.09

1% FCI

45 602.19 13 773 425.79

366

Table 9.5: Manufacturing Cost Summary (Continue)

General Expenses

Administration Cost

5% FCI

228 010.93

Distribution & Selling Expenses

8% FCI

364 817.49

Research & Development

3% FCI

136 806.56 729 634.98

Total General Expenses, AGE Total Production Cost, APC

AME + AGE

14 503 060.77

Depreciation, AD

15% FCI

684 032.79

Total Expenses, ATE

APC + AD

15 187 093.56

RM 40/1 ml Gaharu oil

Revenue from sales/month

1 503 600

2 856 106.44

Annual Profit, ANP Income Taxes

20% annual Profit

571 221.29

Net Annual Profit, ANNP

ANP â&#x20AC;&#x201C; Income Taxes

2 284 885.15

Rate of return

(ANNP + AD) / TCI x 100%

55.17 %

Price of Gaharu oil

= RM 40/1 ml

Revenue from sales of Gaharu oil

= (RM 40/1 ml) x (451 080 ml/year) = RM 18 043 200/ year

367

From the table tabulated with the calculation of rate of return, calculated annual profit for essential oil of Gaharu plant is Annual Profit = Revenue from sales – Total expenses = RM 18 043 200- RM 15 187 093.56 = RM 2 856 106.44

And the income taxes is assumed at 20 % of total annual profit, Income Tax

= 0.20 x (RM 2 856 106.44) = RM 571 221.29

Therefore Net annual profit after deduction of income tax = RM 2 856 106.44 – RM 571 221.29 = RM 2 284 885.15

Carried out calculation for rate of return, Rate of return

= Annp  Ad  100% TCI

2284885.15  684032.79  100% 5381057.98

= 55.17 %

9.5 Cash Flow Analysis

Cash Flow Analysis is done to determine the payback period (PBP), the discounted break event period (DBEP), and net present value (NPV) of our essential oil of Gaharu Plant. Payback period is the time that must elapse after startup until cumulative undiscounted cash flow repays fixed capital investment. To get the

368

payback period, an undiscounted cash flow is calculated and cash flow diagram with i = 0%.

Assumptions for cash flow analysis are as below: a) The construction of the plant takes 3 year before start-up. b) The plant life is taken as 20 operation years. c) Straight-line depreciation is assumed. d) The federal income tax is 30% of net profit with a tax exemption period of 5 years. e) The Sales Income for the first year start up is assumed 80%.

Then, the capital investment used in the first year of the plant is 10 % from Total Capital Investment (TCI) while itâ&#x20AC;&#x;s increased to 34 % of TCI. In the third year of operation, capital investment to the plant account of 65 % of TCI plus the working capital. The production of essential oil of Gaharu in the beginning was expected not achieve the target as desired due to the company is still new. Therefore, an assumption of 80% of the targeted value is set before its back to normal production glow in second year and so on.

To determine the time that must elapse after start up until cumulative undiscounted cash flow repays fixed capital investment, which is PBP, the cash flow diagram of undiscounted must be calculated. Based on the calculated value of net cash income and by referring to cash flow diagram that has been plotted, itâ&#x20AC;&#x;s was clearly show that the Pay-back period (PBP) was estimated of 2.8 years after 3 years of start-up period.

369

Table 9.6: Undiscounted Cash Flow Analysis Plant life

= 20 year

Working Capital

= RM 456 021.86

YEAR 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

CAPITAL INVESTMENT

SALES INCOME

DEPRECIATION

Depreciation = RM 684 032.79

TOTAL EXPENSES

CASH INCOME

NET PROFIT

TCI

= RM 5 381 057.98

FEDERAL INCOME TAXES

NET PROFIT AFTER TAXES

NET CASH INCOME

SUMMATION NET CASH INCOME

-752533.56 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128 2284885.128

-538105.798 -1829559.713 -3041665.827 -68500.77 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918

-538105.798 -2367665.511 -5409331.338 -5477832.108 -2508914.19 460003.7278 3428921.646 6397839.564 9366757.482 12335675.4 15304593.32 18273511.24 21242429.15 24211347.07 27180264.99 30149182.91 33118100.83 36087018.74 39055936.66 42024854.58 44993772.5 47962690.42 50931608.33

-538105.798 -1829559.713 -3041665.827

-538105.798

14434560 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200 18043200

684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79 684032.79

14503060.77 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8 14503060.8

-68500.77 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2 3540139.2

-752533.56 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41 2856106.41

0 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282 571221.282

370

Figure 9.1: Cumulative Annual Cash Flow Profile

371

Table 9.7: Discounted Factor Cash flow Analysis for 10 % & 15 % Year of Completion 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Net Cash Income A(NCI) -538105.798 -1829559.713 -3041665.827 -68500.77 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918 2968917.918

Discount Factor, fd (i =10 %) 0.9091 0.8264 0.7513 0.6830 0.6209 0.5645 0.5132 0.4665 0.4241 0.3855 0.3505 0.3186 0.2897 0.2633 0.2394 0.2176 0.1978 0.1799 0.1635 0.1486 0.1351 0.1228 0.1116

Discounted Cash Flow for 10% sum[A(NCI)*fd] -489187.0891 -1512032.821 -2285248.555 -46786.94761 1843464.442 1675876.765 1523524.332 1385022.12 1259111.018 1144646.38 1040587.618 945988.7439 859989.7672 781808.8793 710735.3448 646123.0407 587384.5825 533985.9841 485441.8037 441310.7306 401100.8107 364583.1203 331331.2396

Discounted Cash Flow for 10% Cummulative -489187.0891 -2001219.91 -4286468.465 -4333255.413 -2489790.971 -813914.2059 709610.1261 2094632.246 3353743.264 4498389.644 5538977.263 6484966.007 7344955.774 8126764.653 8837499.998 9483623.039 10071007.62 10604993.61 11090435.41 11531746.14 11932846.95 12297430.07 12628761.31

Discount Factor, fd (i = 15%) 0.8696 0.7561 0.6575 0.5718 0.4972 0.4323 0.3759 0.3269 0.2843 0.2472 0.2149 0.1869 0.1625 0.1413 0.1229 0.1069 0.0929 0.0808 0.0703 0.0611 0.0531 0.0462 0.0402

Discounted Cash Flow for 15% sum[A(NCI)*fd] -467918.0852 -1383409.991 -1999944.655 -39165.53757 1476076.918 1283545.146 1116126.214 970544.5338 843951.7685 733871.1031 638148.7853 554911.9872 482532.1628 419593.185 364863.6391 317272.7297 275889.3302 239903.7654 208611.9699 181401.7129 157649.5414 137164.0078 119350.5003

Discounted Cash Flow for 15% Cummulative -467918.0852 -1851328.076 -3851272.731 -3890438.269 -2414361.351 -1130816.205 -14689.9911 955854.5427 1799806.311 2533677.414 3171826.2 3726738.187 4209270.35 4628863.535 4993727.174 5310999.903 5586889.234 5826792.999 6035404.969 6216806.682 6374456.223 6511620.231 6630970.731

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Table 9.8: Discounted Factor Cash flow Analysis for 20 % & 30 % Year of Completion 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Discount Factor, fd (i =20 %) 0.8333 0.6944 0.5787 0.4823 0.4019 0.3349 0.2791 0.2326 0.1938 0.1615 0.1346 0.1122 0.0935 0.0779 0.0649 0.0541 0.0451 0.0376 0.0313 0.0261 0.0217 0.0181 0.0151

Discounted Cash Flow for 20% sum[A(NCI)*fd] -448421.4983 -1270527.579 -1760223.28 -33034.70775 1193141.524 994284.6037 828570.5031 690475.4192 575396.1827 479496.8189 399580.6824 332983.902 277486.585 231238.8208 192699.0174 160582.5145 133818.7621 111515.6351 92929.69588 77441.41323 64425.51882 53737.41432 44830.66056

Discounted Cash Flow for 20% Cummulative -448421.4983 -1718949.077 -3479172.356 -3512207.064 -2319065.54 -1324780.936 -496210.4331 194264.9861 769661.1688 1249157.988 1648738.67 1981722.572 2259209.157 2490447.978 2683146.995 2843729.51 2977548.272 3089063.907 3181993.603 3259435.016 3323860.535 3377597.949 3422428.61

Discount Factor, fd (i = 30%) 0.7701 0.5930 0.4566 0.3516 0.2708 0.2085 0.1606 0.1237 0.0952 0.0733 0.0565 0.0435 0.0335 0.0258 0.0199 0.0153 0.0118 0.0091 0.0070 0.0054 0.004 0.0031 0.0024

Discounted Cash Flow for 30% sum[A(NCI)*fd] -414373.7856 -1084915.194 -1388945.813 -24087.61822 803935.4843 619078.6111 476727.7153 367108.9753 282695.9612 217692.8702 167636.5857 129090.24 99407.23859 76549.54458 58947.74725 45393.30606 34955.5722 26917.89019 20728.39226 15962.10709 11875.67167 9203.645546 7125.403003

Discounted Cash Flow for 30% Cummulative -414373.7856 -1499288.98 -2888234.793 -2912322.411 -2108386.927 -1489308.316 -1012580.6 -645471.625 -362775.6638 -145082.7936 22553.79212 151644.0322 251051.2707 327600.8153 386548.5626 431941.8686 466897.4408 493815.331 514543.7233 530505.8304 542381.502 551585.1476 558710.5506

373

Figure 9.2: Cumulative Discounted Annual Cash Flow 374

Table 9.9: Summary of Cash Flow Analysis for Various Interests

Rate of interest, i

Discounted Break Even Point (years)

Net Present Value, RM 460 003.73

10 %

15 %

20 %

194 264.99

30 %

-145 082.79

709 610.13 -14 689.99

(The Discounted Break Even point is counted from the year of start up)

Discounted break-even point is the point in which the time from the decision to proceed until discounted cumulative cash flow becomes positive value. And net present value is the final cumulative discounted cash flow value at project conclusion.

The discounted cash flow rate of return (DCFRR) is the point in which the rate result a Net present value of zero. In this case, the zero value cannot be obtained but the value is near the zero compared to other value, so the difference between the values can be neglected. So, the value of 14.90 % is selected as the break-even point. The DCFRR point is the maximum interest rate that counted after the taxes.

375

9.6 Conclusion

After carried out the economic analysis to the essential oil of Gaharu production plant, the conclusions that can be summarizes as below:

Table 9.10: Summary of Economic Analysis for Essential Oil of Gaharu Plant

Aspect

Value

Grass Root Capital (GRC)

RM 2 886 214.31

Total Capital Investment, TCI

RM 5 381 057.98

Total Production Cost, APC

RM 14 503 060.77

Total Expenses, ATE

RM 15 187 093.56

NET Annual Profit, ANP Income Tax Net annual profit after deduction of income tax, ANNP Pay Back Period

RM 2 856 106.44 RM 571 221.29 RM 2 284 885.15 2.8 years after 3 years start up period

Discounted cash flow rate of return, DCFRR

14.90 %

Rate of return, ROR

55.17 %

Net Present Value (NPV)

RM 460 003.73

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CHAPTER 10

CONCLUSION AND RECOMMENDATION

10.1

Conclusion

The purpose of this report is to design a gaharu oil extraction plant with capacity of 450L per annual. Gaharu is one of the most expensive and highly prized commodities. It can be trade in chips, flakes, oil and powder waste . The gaharu essential oil produced via extraction of gaharu wood is the most common form traded. It have a wide use in medicine (general pain reducer, dental pain, kidney and rheumatism medicine), as venom repellent, in perfume and as incense raw material. Also, it plays roles in traditional Chinese medicine for its sedative, carminative, and anti-emetic effects, and also as incense for religious ceremonies.

377

Among the possible extraction methods, steam distillation is the most favorable due to high conversion of raw material to product, the amount of steam can be readily controlled, no thermal decomposition of oil constituents and it is the most widely accepted process for large-scale oil production.

The proposed location of the plant is in Kulai Johor. The cost of transportation can be reduced by minimizing the distance of the plant and the plantation. Meanwhile this location is strategic because it is situated near to Kulai City which is readily available of manpower supply. Furthermore, electrical supply and water supply facilities are also contributed for the site decision. The transportation facilities include the railway also support to our selection.

After applying the HEN analysis, there are 3 heat exchanger, one hot utilities and two cool utility are designed. The consumptions of utility are almost the same as the one before heat integration. The comparison between the utility consumptions before and after maximum energy recovery (MER) is concluded that the energy saving percentages from the heat integration is much lower than expected. This is due to the less streams that are intensively in need of heating and cooling. For ideal case, the plant is able to save 100.0% of energy for heater utilities and 29.66% of energy for cooling utility. The integrated network has successfully increased the efficiency of the plant in the aspect of energy utilization.

After developed the waste treatment plant, there are 5 major equipments in waste treatment process which are pumps, clarifier, filter press, aeration tank, and equalization tank. The total amount of costing for this waste treatment plant is RM 600 197.31. Nevertheless, we also included the mechanical design which shown the

378

detail and overview for specific equipment. Process safety studies and process control were also conducted to ensure safe operation of the chemical plant.

Economic analysis indicated that this proposed plant will receive a net annual profit after taxes of RM RM 2 284 885.15 with payback period of 2.8 years after 3 years start up period. The Discounted Cash Flow Rate of Return (DCFRR) is 14.90 % and the Net Present Value (NPV) is RM 460 003.73. The rate of return (ROR) of the plant is as high as 55.17 %. Based on the overall plant economic evaluation, it can be concluded that this gaharu oil extraction production plant is indeed economically feasible and thus provide promising return on investment.

10.2

Recommendations

After studied and reviewed the whole process of the plant, there are few recommendations to operate this plant in more efficient way, as stated below:

i) Hazard and Safety

Safety methods and procedures are important for a plant to operate. They should be recommended to ensure the plant safety. For the safety, all the practices during manufacturing the products should be in line with Good 379

Manufacturing Practices (GMP), Hazard Analysis and Critical Control Point (HACCP) and Sanitation Standard Operating Procedures (SSOP) to ensure the VCO produced do not give harm to consumers.

ii) Improvement of Equipment Efficiency

The equipment used is quite expensive. So, we need to operate the process at optimum condition in order to save cost and increase the efficiency of the equipment. By doing this, the yield of the product may increase.

iii) Waste management

All the waste produced from this plant is not harmful and have the economic potential to be sold to other company. So, the waste produced should be stored properly in order to avoid it losing its economic value.

380

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