IWW Technical Session on
“Mandatory Water Audit for Domestic and Industrial Water Supply”
FICCI Water Audit Case Study of a Gas Based Power Plant in India: Improving Water Use Efficiency Karishma Bist
Dy. Director FICCI - Resource Conservation & Management Group Email: karishma.bist@ficci.com 1
About Resource Conservation & Management (RCM)
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Need for Water Conservation & Management
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Water Consumption Scenario: Indian industry Vs Global best Average water consumption in Indian industry
Sector
Thermal Power plant
Textiles Pulp & Paper
average 80 m3/ mwh(1)
Less than 10 m3/mwh
200-250 m3/ tonne cotton cloth(3)
Less than 100 m3/ tonne cotton cloth (2)
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Wood based mills: 150 200 m3 / tonne(3) Waste paper based mills: 75 -100 m3/ tonne(3)
10-80 m3 per tonne of Integrated finished product Iron & (average) steel plant
Distilleries Fertiliser industry
Globally best
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Wood based mills: 50 - 75 m3 / tonne (4) Waste paper based mills: 1025 m3/tonne(4)
5 -10 m3 per tonne of finished product. (5)
75-200 m3/ tonne alcohol produced(6) •
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(2)
Nitrogenous fertiliser plant - 5.0 - 20.0 m3/ tonne(3) Straight phosphatic plant - 1.4 - 2.0 m3/ tonne (3)
Data not available An effluent discharge of less than 1.5 m3/ tonne product as P2O5 (2)
Source: 1. No credible data available. Estimates done by CSE from wastewater discharge data from "Water Quality in India, Status and trends (1990-2001), CPCB, MoEF" and annual electricity generation data from "Annual Report (2001-2002) on the working of state electricity boards and electricity department, Planning Commission." 2. Pollution prevention and abatement handbook, World Bank. 3. Environmental management in selected industrial sectors - status and need, CPCB & MoEF, February, 2003. 4. Green Rating of Pulp and Paper Sector, CSE. 5. Integrated Pollution Prevention and Control (IPPC), Best available techniques reference document on the production of iron. 6. Environmental performance of Alcohol industry in UP, UPPCB, 2000-2001.
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Water Audit – Scope, Components and Methodology
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What is Water Audit? • Water Audit study is a qualitative and quantitative analysis of water consumption which helps efficient water utilization & conservation. • Water Audit determines the amount of water lost from a distribution system and the cost of this loss to the utility. • Comprehensive water audit envisages a detailed profile of the distribution system and water users, thereby facilitating easier and effective management of water resources and improved reliability. 6
Water Audit Studies Can be Done for any Water Utilizing Unit/System/Process/Project
• Industrial Units • Office Buildings • Residential Colonies and Individual Houses • Hospitals and Hospitality Sector • Airports • Water Supply & Distribution Boards • Regional/ Cluster Level Audits
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Why Water Audit Poor Availability or Non-Availability of Fresh Water Higher Specific Water Consumption High Water Bills Inconsistent Product Quality High Effluent Discharge Restriction on effluent Disposal to any Recipient Media Breakdowns, Leakages & Spillages Cost of Pumping < Cost of Filtered Water from WTP < Cost of Softened Water < Cost of DM Water
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a+3b+3c DM Water
a+b
Overhead Tank
WTP
Process Soft water a+3b+2c Cooling
a+2b a
Domestic etc. Filtered water a+3b+c
a â&#x20AC;&#x201C; cost of raw water b- pumping cost c- treatment cost 9
420m³/day @ Rs.1.16/m³
447m³/day @Rs.2.31/m³
Reservoir 1 Re 0.95/m³
Re 0.20/m³
Reservoir 2
Reservoir 3
@Rs.1.47/m³ 9m³/day @ Rs.3.78/m³
32m³/day Tube Settler
136m³/day @Rs.6.69/m³
Softener 1 Re0.79/m ³
408m³/day
IRF 1 Rs.2.91 /m³
Canteen MGF 1 435m³/day @Rs.3.78/m³
180m³/d @Rs.6.69/m³ 92m³/day Rs.6.69/m³
Storage (10KL)
3m³/day Rs.3.78/m³
Plant/Printing Hand Washing in Toilets
8m³/day @Rs.7.2/m³ 262m³/day @Rs.7.2/m³
103m³/day @Rs.7.2/m³
170m³/day @Rs7.48/m³
Plant/ Printing/Drinking Water 151m³/day @Rs.7.2/m³
Re0.67/m³
Colony
Process 130m³/d @Rs.7.36/m³
46m³/d @Rs.11.54/m³ Softener 2 Re0.57/m³
IRF 2 Rs3.62/ m³
MGF2 125m³/d
121m³/d @Rs.10.97/m³
112m³/d @Rs.11.54/m³
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66m³/d Rs.11.54/m³
40 m3/day Rs 53/m3 RO Plant @Rs.41.52/³ m
Boiler
TYPICAL WATER AUDIT SCOPE
•Development of Water Circuit Flow Diagram •Collection & compilation of basic data of pumps, reservoirs c. •Measurement of Flow, Pressure & Power at major pumps. •Performance Assessment of Pumps-actual v/s rated efficiency. •Identification of inefficient pumps & recommendations. •Preparation of Water Balance Diagram. •Estimation of water losses. •Recommendations on water conservation & cost reductions. •Suggestions on recycling options for water conservation IN ADDITION, FICCI DOES THE FOLLOWING……… 11
FICCI’S ADDITIONAL WATER AUDIT SCOPE
• Value added costing of water cost at various use locations. •Assessing the logistics of existing water management practices & suggesting appropriate changes for reducing overall costs & improved water management. • Incorporating latest water conserving equipments/ technologies in recommendations. • Provide details on Rainwater Harvesting (RWH) potential for the given site and suggest possible RWH schemes. •Evolving WATCON (Water Conservation) options with its techno-economic feasibility aspects. 12
FICCI WATER AUDIT STUDY – SECTORS • • • • • •
• • • • • •
Cement Iron & Steel Beverage Pulp & Paper Pharmaceuticals Ore Beneficiation
Textile Chemical Oil Refinery Aluminium Power Plants Buildings
More than 40 Water Audits done (ITC, NTPC, BPCL, BALCO, RBI, Essar Steel, JK Lakshmi Cement, UltraTech Cement, UB Group, Coca Cola India Inc, HZL, ACC Ltd etc). The Scope of Water Conservation estimated to be about 15-30 Percent in the above sectors 13
FICCI WATER AUDIT– CASE STUDY GAS BASED POWER PLANT
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Current Water Scenario:
431 MW Gas Based Power Plant Main Raw Water Source – Surface Water Total Fresh Water Use = 13,800 m3/day Cost of Raw Water=Rs 3.57/cubic meter Cooling Tower Make Up = 11400 m3/month
MEASUREMENTS CONDUCTED Measurement Locations: The measurements at Water Source side were carried out at: Canal Water pumps The measurements at Distribution side were carried out at Raw Water Pump House - Clarifier Pumps Raw Water Pump House – PT Pumps Cooling Water Make Up Cooling Towers Pumps Cooling Towers – Uprisers, Common Header Output DM Plant – Filter Water Transfer Pumps DM Plant – Degassifier Pumps DM Plant – Regeneration Pumps Fire Water Pumps Tube Well Pumps Condenser Line Input Condenser Line Output
Water Balance Diagram
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Water Use Pattern
Observations
1. Clarifiers: Observation: 2 nos. of clarifiers; only one is operating at a time. Design Capacity of each Clarifier = 720 m3/hr. Operational capacity = 575-600 m3/hr. Turbidity reduced from 80 NTU to 40 NTU After subsequent sand filtration, turbidity reduced to 15 NTU. Filtered water stored, pumped to the cooling towers
Proposed Scheme:
Benefit of the proposed scheme:
Improved efficiency of Sand bed Filters due to reduced turbidity of clarified water Increased COC in the cooling Towers due to reduced turbidity in make-up water Decreased effluent generation due to lesser blow downs in cooling towers reduced dependency on groundwater for making demineralized water
2. Existing Cooling Towers: The cooling Towers accounts for about 83% of total water use in the unit. The unit has 3 nos. of pumps for pumping hot process water to process cooling area. The flow in the main header is about 24,200 m3/hr. The existing CT has total 18 no. of CT cells; 9 even numbered cell and other 9 odd numbered cell
Locations of measurements at Cooling Towers
Process Water Flow Distribution
Percentage deviation of the hot process water distribution in Cooling Towers Odd Cells 1 3 5 7 9 11 13 15 17 Even Cells
flow(m続/hr) 1089 1274 1132 1367 1268 1276 1328 1256 1054
% 88.75 103.82 92.25 111.40 103.33 103.99 108.22 102.36 85.89
% Deviation from the Average -11.25 3.82 -7.75 11.40 3.33 3.99 8.22 2.36 -14.11
2 4 6 8 10 12 14 16 18
980 1054 1180 1142 1223 1018 1235 1380 1070
85.78 92.26 103.29 99.96 107.06 89.11 108.11 120.80 26 93.66
-14.22 -7.74 3.29 -0.04 7.06 -10.89 8.11 20.80 -6.34
Recommendation Ensuring Uniform Water Flow Distribution in all 18 cells of cooling towers by adjusting flow Control valves: ď&#x192;&#x2DC; The cells receiving higher flow rate are expected to have increased drift losses, reduced cooling and overall low efficiency whereas the cells receiving lower flow rates would remain under utilized.
ď&#x192;&#x2DC;This can be achieved by adjustment in setting of valves in each cells so that the flow is equally distributed and regulated.
3. Existing Wastewater Collection & Treatment Wastewater from other sections of the unit Cooling Tower Blow Down
Boiler Blow Down Lime dosing
Wastewater from DM plant
Wastewater Collection Pit
Effluent disposed to Surface Water
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Recommendations Wastewater Treatment Scheme I Wastewater Wastewater containg containgoil oil Rain Rainwater waterfrom from oil tank oil tankyard yard
Waste Wastewater waterfrom fromCT CT and Boiler blow down and Boiler blow down
Oil OilSeperator Seperator Tank Tank
Storage Storage tank tank
neutralizing neutralizing tank tank
wastewater wastewaterfrom from general generalsections sections Wastewater Wastewaterfrom fromDM DM plant plant
congulating congulating sedimentatio sedimentatio nntank tank
Activated Activated Carbon Carbon Filter Filter
Ultra Ultra Filtration Filtration Membranes Membranes
pH pH balancing balancing tank tank
Treated Treated effluent effluent tank tank Recycle in raw water pump house clarifier
Reuse in Landscaping /Horticultur e
Recommendations Wastewater Treatment Scheme II with RO
Schematic Diagram of RO plant with pre-treatment
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4. Rainwater Harvesting The unit has implemented RWH to certain extent, it is observed that the present RWH system is not very efficient. The unit has four recharge pits, two are located within the premises of the unit and another two are located in the township. The 2 nos. recharge pits in the unit are designed to recharge ground water in rooftop runoff. It is also observed that the bore well no. 1(near DM plant storage tank) has very low yield, about < 40 % of its rated capacity
Implementation of Rain Water Harvesting Scheme to Recharge Ground Water: ď&#x192;&#x2DC; The rainwater harvesting potential of the plant is about 77,408 m3 per year. ď&#x192;&#x2DC; The unit can store the rainwater in reservoirs or artificially recharge the groundwater S.No .
Catchment Details
Area (Sq. meter)
Permit area* (Sq. meter)
1 2
Avg. Runoff RWH Rainfall coefficie Potential / Year nt (m3) (m)
Roof-Top Area
20234
14164
0.564
0.75
5991
Open Area (Paved/ unpaved/ Green)
602982
422087
0.564
0.2-0.5
71417
Total RWH Potential (m3)
77408
5. Replacement of Less Efficient Pumps: Location/Pump
Pump No.
Water Delivered To
Power KW
Flow
Press
Actual
m3/hr
m
97.5
1260.0
17.0
117.2
1336.0
20.0
35.4 35.8 36.7 17.3 17.5 16.6 27.8 24.9
576.0 588.0 574.0 128.5 131.0 137.0 107.0 96.5
6.5 7.0 6.0 23.5 24.0 23.5 34.5 38.0
73% 34% 37% 30% 56% 58% 62% 43% 47%
27.5
99.0
32.0
37%
39.6 34.9 34.4 1.6
100.0 101.0 102.0 50.0
36.0 41.0 39.0 5.6
29% 38% 37% 56%
1.7
70.0
5.8
25.7
520.0
9.5
79% 62%
25.2
581.0
11.5
85%
1180
13800.0
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CWP-B
82%
1188
12375.0
24.2
81%
CWP-C
1190
14200.0
22.8
87% 31% 44%
Description Canal Raw Water Pump Cooling Water RW Pump PT Raw Water Supply Pump
Filter Water Transfer Pump( DM Plant)
Degassifier Water Pump Regeneration Pumps CT Make Up (Filter Water Transfer Pumps)
CW Pumps
Blow Down Pumps
Tube Wells Pumps
Filter Back Wash Pumps
RWC RWB
Plant Reservoir
P4A P4B P4C P3A P3B P3C P1A P1B P1C
Clarrifier
PTPlant
DM Plant
P2A P2B P2C P3A P3B
DM Storage
A B
Cooling Towers
CWP-A
Cooling Water in Process
SAC, WAC
BDP/P1 BDP/P2 2.0
Blow Down
8.6 10.9
75.0 106.0
11.0 14.0
Plant & ADM Building
12.6
41.7
40
1.0 3.0 A B
DM Plant DM Plant Steer Chamber Steer Chamber
12.7 18.1 5.8
22.4 45.3 27.0
39 46 20.5
Actual Pump Eff(%) 70%
42% 22% 37% 31%
• Overall the study identified the potential of about 20% saving of total freshwater consumption and ‘Zero Discharge’ potential by implementing the suggested schemes.
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Conclusion •Proactive Approach •Incentives - Certification •Quantitative Guidelines •Effective Enforcement •Stakeholders Responsibility
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We are here to serve you Karishma Bist
Dy. Director FICCI - Resource Conservation & Management Group Email: ma.patil@ficci.com
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