Water & Sanitation Africa Jan/Feb 2014

Promoting professional excellence in the water sector

Water& Sanitation The official magazine of the Water Institute of Southern Africa

Complete water resource and wastewater management

Africa

NUWATER growth phase Entering a new

WATER ANALYSIS Mpumamanzi – a fully fledged black-owned company

IN THE HOT SEAT

COMBINED HEAT AND POWER Johannesburg Water’s first combined CHP plant

Part of the vision is developing long-term solutions to water supply strategies in South Africa. Nandha Govender, general manager: water and environmental operations at Eskom

P8

MEDIA

January/February 2014 • ISSN 1990-8857 • Cover price R40.00 • Vol 9 No. 1

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C O NT N T ENTS S

Volume 9. No.1

Promoting professional excellence in the water sector

Water& Sanitation The official magazine of the Water Institute of Southern Africa T

Complete water resource and wastewater management

Africa

Entering a new

NUWATER growth phase

ON THE COVER

NuWater consolidates its position in subSaharan Africa p4

16 Membrane bioreactor solves Malmesbury's water challenges

COVER STORY NuWater enters new growth phase WISA YWP: YWPs with the ‘Gift of the Gab’ President’s comment: The importance of water reuse

4

6 7

HOT SEAT Eskom: Committed to sustainable water use

8

FEATURES LABORATORIES Processes and challenges of analytical services SA’s expertise in water analysis WATER TREATMENT Stellenbosch rivers still in dire straits?

Membrane bioreactor solves Malmesbury’s water challenges Water infrastructure overhaul continues Serious about water Optimising sludge treatment INDUSTRY NEWS Davey signs distribution agreement with SafeQuip Award for WRC wetland management tool Design challenge winners raise the bar Turning the tide on SA’s water management challenges

WATER ANALYSIS Mpumamanzi ‒ a fully fledged black-owned company

IN THE HE HOT OT SEAT ATT

COMBINED HEAT AND POWER Johannesburg Water s first combined CHP plant

PPart of the vision is developing long-term solutions to water supply strategies in South Africa. Nandha Govender, general manager: water and environmental operations at Eskom

P8

MEDIA

January/February 2014 • ISSN 1990-8857 • Cover price R40.00 • Vol 9 No. 1

PROFILE Quality Filtration Systems

57

TECHNICAL PAPER The installation of CHP at Johannesburg’s Northern WWTW

59

PROFILE Conditioning monitoring software

63

INTERNATIONAL Yorkshire Water chooses local company

42

REGULARS Editor’s comment

3

11 13 16 18 23 24 26 28 32 35

56

Local company appointed business analytics partner

58

Combined heat and power: a first for South Africa

36

DAMS AND RESERVOIRS The Mooi-Mgeni Transfer Scheme’s second phase completed Bulk water supply investigation under way Mammoth tank for Medupi manufactured South African contractor to the rescue

39 41 43 45

TRENCHLESS TECHNOLOGY Trenchless solutions go a step further Focusing on service delivery

47 50

WATER METERING Call for intelligent water management solutions Intelligent metering offers tight control Meter readings can save water

53 55 56

JANUARY/FEBRUARY 2014

1

BUSINESS

TRC/0205/E

* Savings are based on individual customer case studies; these may vary depending on usage and package

Publisher Elizabeth Shorten Editor Maryke Foulds Head of design Frédérick Danton Senior designer Hayley Mendelow Designer Kirsty Galloway Chief sub-editor Claire Nozaïc Sub-editor Beatrix Knopjes Contributors Shanna Nienaber, Malcolm Corns, Peter Leopold, Shaun Deacon, Peter Louw Marketing manager Hestelle Robinson Digital manager Esther Louw Client services & production manager Antois-Leigh Botma Production coordinator Jacqueline Modise Distribution manager Nomsa Masina Distribution coordinator Asha Pursotham Financial manager Andrew Lobban Administration Tonya Hebenton Printers United Litho Johannesburg +27 (0)11 402 0571 Advertising sales Avé Delport Tel: +27 (0)11 467 6224 • Cell: +27 (0)83 302 1342 Fax: 086 502 1216 • Email: avedel@lantic.net

EDITOR’S COMMENT FEATURE

Commitment to the water industry is crucial

A

T THE TIME OF WRITING this editor s comment, the water sector is in the news for all the wrong reasons.

The situation in the Mothutlung Township

outside Brits has escalated into violent protest. Access to clean water and basic sanitation is a fundamental human right. When violence erupts due to the lack of this basic service, it is time for government to take

Publisher

action. Hopefully, the municipality will act on its investigation on reasons why all three local water pumps broke down, rendering the township without water for

Physical address: No 4, 5th Avenue Rivonia 2056 Postal address: PO Box 92026, Norwood 2117, South Africa Tel: +27 (0)11 233 2600 Fax: +27 (0)11 234 7274/5 Email: maryke@3smedia.co.za MEDIA

three months.

Industry for its part can play an important role in continuing to highlight water infrastructure problems in the country. It does, however, bring into sharp focus the need for trained technical staff within municipalities as well as funding to follow these projects through. Another critical aspect is a radical improvement in water quality management approaches and

ISSN: 1990 - 8857 Annual subscription: R290 (SA rate) Email: subs@3smedia.co.za Copyright 2014. All rights reserved.

treatment technologies. This is where Water&Sanitation Africa plays a critical role: providing all role players with the latest in new technologies, products and services, as well as special infrastructure projects.

All articles in Water&Sanitation Africa are copyright protected and may not be reproduced either in whole or in part without the prior written permission of the publishers.

The views of contributors do not necessarily reflect those of the Water Institute of Southern Africa or the publishers.

That said, in this issue we look at a number of interesting projects, including commissioning of a Combined Heat and Powerplant at Johannesburg s Northern Wastewater Treatment Works. This initiative is aimed at offsetting increases in electricity tariffs imposed by Eskom and will have a direct bearing on the operational expenditure of wastewater treatment in Johannesburg.

WISA CONTACTS:

We also look at the recent installation of a new hybrid membrane bioreactor that is

HEAD OFFICE Tel: +27 (0)11 805 3537 Fax: +27 (0)11 315 1258 Physical address: 1st Floor, Building 5, Constantia Park, 546 16th Road, Randjiespark Ext 7, Midrand BRANCHES

designed to treat an average flow of 10 000 m3/day of wastewater in the Swartland in the Western Cape. The construction of the activated sludge plant is allowing the Swartland Municipality to set new standards in the treatment of wastewater, which will transform water quality in the region.

www.ewisa.co.za

WISA is also proud to announce the appointment of its new CEO, Lester Goldman,

Eastern Cape Chairman: Hennie Greeff Tel: +27(0)41 453 3102 Secretary/Treasurer: Chris Dickson Tel: +27(0)41 507 8200

which was affected on 1 January 2014. Goldman, described as a highly motivated and energetic leader, will bring to WISA his strengths in financial management and good governance, business management, business strategy and marketing. Look out for a full profile in the March/April issue.

Free State Chairperson: D.R. Tlhomelang Tel: +27(0)51 403 0800 Secretary/ Treasurer: Riana Wessels Tel: +27(0)56-515-0375

Lastly, the WISA conference, which will take place from 25 to 29 May in Mbombela, is a not-to-be-missed event. Early-bird registration is now open. Please go to www.wisa. org.za for more information.

As this is my first issue as editor, I would appreciate your comments and suggestions

KwaZulu-Natal Chairman: Chris Fennemore Tel: +27 (0)31 311 8734 Secretary/ Treasurer: Stephanie Walsh Tel: +27 (0)31 302-4077 Western Cape Chairman: Gareth McConkey Tel: +27(0) 21 712 4260 Secretary/ Treasurer: Eleonore Bondesio Tel: +27(0)21 872 0322

on the contents you would like to see published. Please feel free to contact me directly at maryke@3smedia.co.za. I look forward to taking this journey with you.

excellence

M Maryke Foulds,

sector in the water

itation Water& San Africa Promoting

professional

magazine The official T

Com plet e

urce wate r reso

ewa ter and wast

Institute of the Water

man agem

Entering a

of Southern

Africa

Ed Editor

ent

new

Cover opportunity

se growth pha NUWATER

WISA mission statement The Water Institute of Southern Africa provides a forum m for exchange of information and views to improve water resource management in Southern Africa.

Endorsed by

POWER HEAT AND COMBINED Water s first Johannesburg d CHP plant combine

LYSIS WATER ANA ‒ a fully fledged Mpumamanzi ed company black-own

IN

HE THE OT HOT ATT SEAT

solutions to g long-term der, is developin . Nandha Goven PPart of the vision in South Africa at Eskom P8 ly strategies al operations water supp er: water and

general manag

environment

January/February

1990-885 2014 • ISSN

MEDIA

1 • Vol 9 No. price R40.00 7 • Cover

In each issue, Water&Sanitation Africa offers companies the opportunity to get to the front of the line by placing a company, product or service on the front cover of the magazine. Buying this position will afford the advertiser the cover story and maximum exposure. For more information on cover bookings contact Avé Delport on +27 (0)83 302 1342 or e-mail avedel@lantic.net

JANUARY/FEBRUARY 2014

3

COVER STORY

NUWATER

NuWater enters new In the mere three years since NuWater arrived on the South African water treatment and wastewater reclamation and reuse scene, it has managed to consolidate its position as one of the most innovative and successful solutions and services providers in sub-Saharan Africa.

W

ATER&SANITATION AFRICA spent time with NuWater s CEO, John Holmes, and other members of the team to better understand the basis of their success to date

and to get a sneak preview of what they have planned for 2014.

Says Holmes:

ABOVE Gold Fields Tarkwa

producing a few thousand litres per day through to large

FAR RIGHT NuWater Small Plants on the move

ogies incorporated in the plants also vary depending on

plants producing millions of litres per day. The technolthe application ‒ from simple media filtration through to sophisticated membranes for desalination. In terms of flagship projects, however, our plants at Anglo American

Although we are very much a for-

Thermal Coal s New Vaal Colliery near Vereeniging and

ward-looking company focused on improving our product

Gold Field s Tarkwa mine in Ghana stand out on the

offering and driving further growth, it is worth reflecting

world stage.

occasionally on what we have achieved so far in a very short period of time.

NuWater has been operating its completely modular and re-deployable plant at Anglo New Vaal since late

From a standing start in 2010 we have designed,

2010, producing up to 20 Mℓ/day of high-quality water

built and commissioned a number of highly innovative

from the mines wastewater for reuse as cooling water

world-class plants for the treatment and reclamation of wastewater for reuse or safe disposal back into the environment. In addition, we maintain ownership of some of these plants, effectively providing a complete service to our customers without them having to undertake the significant capital investment that would otherwise be required. NuWater also maintains an active role in the operations and maintenance of all its plants. So in essence we see ourselves in partnership with our customers as our interests and theirs are so closely aligned.

at

NuWater’s broader ambitions in the rest of sub-Saharan Africa have also been boosted by its success with Gold Fields in Ghana

Eskom s

neighbouring

Lethabo Power station. The plant is required to remove a high concentration of small suspended solids as well as dissolved salts that make the water unsuitable for dis-

charge into the environment or for reuse.

The plant incorporates advanced membrane technology in the form of ultrafiltration for suspended solids removal and reverse osmosis (RO) for dissolved

Solid platform

salt removal. NuWater s patented 16 RO is critical to

Holmes is not talking about just any old customers. In the

achieving the plant s compact footprint that allows it

three years of operation, NuWater has executed major

to be rapidly deployable and,

projects for the likes of Anglo American and Gold Fields

if

to ensure that wastewater from their mines is suitable as

NuWater retains ownership of

drinking or high-quality process water.

this plant and is responsible for

He continues: We have very loyal and satisfied cus-

redeployable.

all operational aspects.

tomers, from individual property owners through to

4

necessary,

What

is

most

rewarding

municipalities and large blue chip corporate customers.

about this project is that it has

NuWater offers a range of plants starting with small plants

changed perceptions of what

JANUARY/FEBRUARY 2014

COVER STORY

growth phase a desalination plant should look like and

technology is an important part of this, but

removing bacteria, making it ideal for water

how it should operate. Before this project,

obviously only addresses applications where

recycling applications.

the view was that a large fixed plant, like

desalination is required for the removal of

He continues: This technology has excel-

a factory, is required to desalinate large

salts from sea or brackish water, including

lent physical properties making it resilient

volumes of water. NuWater has proved that

mine drainage water.

to solvents, oils and other chemicals. This

a very flexible pre-built packaged plant can

What we have been

resistance to chemical damage as well

achieve the same results at a lower cost and

working on is a technology that is suitable

as thermal degradation makes it suitable

with far greater technical and commercial

for a broad range of applications requiring

for applications and operating conditions

flexibility. What we have achieved is not

the separation of solids from liquids that is

where most membranes simply would not

straightforward, as some of our competitors

highly durable and that requires very little

last. The technology benefits further from

have found out. The investment we have

energy to operate.

the fact that it is very compact due to its

He continues:

made in ensuring the success of this project

highly sustainable flux rate and is, at the

has been rewarded by Anglo with further

The next big thing

contract extensions, states Holmes.

So what new product offering will NuWater

NuWater s broader ambitions in the rest of

same time, easy to maintain.

be launching?

Jean Vos, head of African sales for NuWater, adds: We see huge potential for

As of February

this new product in South Africa and the

2014, NuWater has launched a new product

rest of Africa as it is able to scale from small

The project in Ghana, executed with

range for water and wastewater treatment

simple applications to large sophisticated

support from Murray & Roberts, has further

applications that is incredibly simple in its

plants. Energy consumption is also critical

demonstrated the value of NuWater s mod-

design and that is significantly more com-

and means that small plants can be driven

ular, rapidly deployable and redeployable

petitive in terms of capital and operating

by solar power or even manually. This all

plant design, Holmes says. At a practical

costs than comparable technologies such

makes this advanced technology accessible

level, we have also demonstrated our ability

as membrane offerings. In addition, the

to a far larger segment of the population,

to execute logistically complex projects in a

NuWater system can withstand chemical

which will help bring safe drinking water to

challenging operational environment. This

and most physical damage. What is most ex-

all and allow water to be more effectively

stands us in good stead for future projects.

citing is the low energy requirement, which

reclaimed and reused. We will be out on the

is up to 80% less than most comparable

road demonstrating this new product to a

Back to the future

membrane technologies achieving similar

large number of people across South Africa

On the subject of plans for 2014, there is

solids-liquid separation.

and other selected African countries in the

sub-Saharan Africa have also been boosted by its success with Gold Fields in Ghana.

According to Nathoo:

a palpable excitement in the air. Jeeten

Asked what the target market for this

Nathoo, NuWater chief technical officer,

exciting development would be, Nathoo

gives his assessment of the company from

replies: This new product is suitable for

In summing up NuWater s plans for 2014

a technology perspective:

NuWater is a

most water treatment applications includ-

and beyond, Holmes says: The addition of

multi-discipline company able to execute all

ing municipal and industrial applications.

another exciting technology to our portfolio

aspects of challenging large-scale projects,

It is also well suited to RO pre-treatment as

will enhance our offering for the mining

covering design engineering, manufac-

it can handle very high loads of suspended

sector, other industrial customers, and the

turing,

and

solids. Its ability to handle these high

private and municipal markets. We intend

financing. At its heart, however, NuWater

levels of suspended solids also makes it

offering further innovative technologies

is a technology-led organisation driven by

an ideal alternative to clarifiers and media

later in 2014 and beyond to support our

the desire to offer products that achieve a

filters, and it competes very well against

ambition of delivering the most compelling

step-change in terms of performance, reli-

these competitor technologies on cost as

and cost effective solutions and services

ability and affordability. Our proprietary RO

well. The technology is highly effective in

available in the market.

commissioning,

operations

JANUARY/FEBRUARY 2014

coming months so that people can get a first-hand feel for the product.

5

YOUNG WATER PROFESSIONALS

WISA

YWPs with the ‘Gift of the Gab’ Public speaking, debating and communication skills are essential competencies to excel in the water sector. By Shanna Nienaber, chair of Gauteng YWP

The debating teams engaged in a postdebate analysis

participants engaged in two challenging debates. The first topic analysed whether

programme was first presented at the

or not transdisciplinarity is an appropri-

International Conference on Freshwater

ate approach for doing water-related

Governance for Sustainable Development

research, development and innovation.

in 2012. In 2013, the Department of

The second topic looked at multilateral

Science

water governance treaties and whether

a

and

second

Technology competition,

which was run at the WRC Research,

Development

and Innovation Symposium, which took place from 25 to 27 September in Pretoria.

In order to support YWPs in developing these skills, the Southern African YWP Committee has developed a Public Speaking Development Programme in the form of a debating competition

T SOME POINT in our careers

Eight

we all are confronted with a

students

situation where we have to

universities around the country were

or not they are needed for the effective

present our research, engage in

selected and funded to participate. The

management of transboundary rivers in

a panel debate, convince someone about

participants were purposefully grouped

Southern Africa.

the validity of a point, or sell a new con-

into multi-disciplinary teams in order to

cept or idea.

encourage

A

postgraduate from

different

cross-disciplinary

This event, once again, proved to be a

thinking

resounding success. It was exciting to see

Whether or not you re a natural public

and debate. In preparation for the public

the improvement in the quality of pres-

speaker, this is a skill that can be im-

debates, the teams engaged in a series of

entations by the participants. The lunch-

proved, refined and developed over time.

workshops to refine their content knowl-

time audience was thoroughly engaged

edge about the topics and also to practise

in the heated debates and arguments

their public speaking skills.

presented by the students. There was

In

order

Professionals

to

support (YWPs)

Young in

Water

developing

these skills, the Southern African YWP

The focus of this year s competition

also enormous learning and networking

Public

was water cooperation, in celebration of

opportunities for the participants given

Speaking Development Programme in

the UNESCO International Year of Water

that they were part of a larger nation-

the form of a debating competition. This

Cooperation. To unpack this diverse topic,

al symposium.

Committee

6

sponsored

has

developed

a

JANUARY/FEBRUARY 2014

PRESIDENT'S COMMENT

WISA

The importance of water reuse In this edition I would like us to focus our energy on supporting the newly established Water Reuse Division (WRD) in WISA, which is under the chairmanship of Chris Swartz.

HE WRD COMES AT A TIME

in Windhoek, Beaufort West, eThekwini,

• organise

when the No Drop Certification

Cape Town, Hermanus, Mossel Bay and

conferenc-

System has been introduced by

George. Conventional water sources are

es,

the Department of Water Affairs.

increasingly unreliable due to droughts,

posiums

The International Water Association (IWA)

urbanisation, etc. There is, therefore, a

and plant visits (this can be done jointly

Water Reuse Specialist Group Conference

need for a local and regional forum and

with the WISA Membrane Technical

was held in Windhoek, Namibia from 28

platform to share information and knowl-

Division

to 31 October 2013. The conference was

edge to enable planners, researchers and

Oxidation Technical Division)

attended by 400 water reuse specialists

professionals to come up with sustainable

from around the world, and we had the

solutions. There is already a pool of exper-

opportunity as the newly formed WISA

tise and vast institutional knowledge in

• develop/facilitate courses

WRD to do some good networking and

Namibia and South Africa on water reuse,

• identify research needs

T

also promote the work that we

are

doing.

Southern

Africa is proud to have the world s first direct potable reuse plant in Windhoek (the New Goreangab Water Reclamation Plant), and also

sym-

and

the

WISA

Advanced

• build expertise and knowledge within the sector

• stimulate awareness within the water

The objective of the WRD is to provide a communication forum for engineers, scientists and practitioners to share information and knowledge

sector and the public at large • prepare newsletters of WRD activities and developments • maintain a WRD website within the WISA website.

the first small municipality direct potable

and we now need to share this knowledge

Scope of interest

reuse plant in Beaufort West. A number

for the mutual benefit of all the commu-

The following subject areas will be includ-

of Southern African presentations and

nities in the region. Reuse is currently a

ed in the scope of activities of the WRD:

workshops

including

high-priority discussion topic. A major

• health aspects (microbial and chemical

direct and indirect reuse as well as mine

objective of the new division will also

water reuse.

be to inform national, regional and local

• advanced water treatment technologies • monitoring needs (treatment processes

were

presented,

constituents of concern,)

The inaugural meeting of the WISA WRD

authorities of the benefits of reuse, health

was also held at the Windhoek confer-

aspects, public acceptance, governance

ence. An introductory presentation was

and regulatory matters.

• water quality monitoring (new meth-

Valentina Lazarova gave an overview of

Objective

• management and operational controls

the activities of the IWA in general, and in

The objective of the WRD is to provide

• public acceptance

specific on the IWA Water Reuse Specialist

a communication forum for engineers,

• regulatory aspects

Group. Swartz presented a draft consti-

scientists

• improved integration in water resourc-

tution for the new division, which was

information and knowledge on water

discussed by the delegates. Nominations

reclamation, recycling and reuse in order

were subsequently requested for mem-

to facilitate the implementation of safe

bers to act on the management com-

water reuse practice in Southern Africa.

• operation and maintenance in the re-

proposed:

Activities

• risk management.

• Dr EJ Ncube (Rand Water)

The division will undertake the following

I sincerely trust that the aforesaid will

• Dr N Kalebaila (WRC)

activities:

whet your appetite for participation in the

• provide a communication platform for

WRD and that you will join the division

ods; sensors)

provided by Chris Swartz, after which Dr

and

practitioners

to

share

J

Menge

(City

of

Windhoek/

consultant) • Mr J van Eeden (Royal HaskoningDHV) • Mr E du Toit (Dow Water and Process Solutions).

es management • better energy efficiency in water reclamation and reuse use projects

mittee, and the following persons were

• Mr

and product water)

all stake-holders

and support the initiatives relating to wa-

• exchange relevant information to im-

ter reuse in your respective organisations

prove management, operation, design

as it forms a strategic part of water re-

and regulation

source optimisation and management.

• hold regular meetings and workshops

Need for the WISA WRD

• build the capacity of Young Water

Water reuse is receiving considerable

Professionals

attention in Southern Africa, most notably

water sector

(YWPs)

in

the

local

Ronald M Brown President

of

the

Water

Institute

of

Southern Africa

JANUARY/FEBRUARY 2014

7

HOT SEAT

ESKOM

Committed to sustainable Eskom recently received a silver commendation during the Department of Water Affairs 2013 Water Conservation and Water Demand Management Sector Awards.

Maryke Foulds speaks to the GM of Water and Environmental Operations at Eskom, Nandha Govender, about the company’s vision of sustainable water management at the utility and how this award validates the work Eskom is doing.

RAINED AS A mechanical engineer, Govender

working together to address these challenges with sup-

has spent the past 15 years as a passionate

port from government. Eskom, together with government

champion of water causes in South Africa. He

and the private sector, is currently active in the Effluent

says: Part of the vision is to develop sustainable

and Waste Water Working Group through the South

long-term solutions to water supply challenges in South

African Strategic Water Partners Network to provide solu-

Africa as well as the optimum management of water with-

tions to turning the mine water problems in the Olifants

in Eskom s operations and facilities.

Catchment into a sustainable resource for the benefit of

T

There are a number of facets to this operation. We have

the catchment and its water users. The aim of the working

to look at integrating water risks in our short- to long-term

group is to unblock all the constraints and issues in the in-

business planning and decision-making, with a major focus

stitutional, regulatory and pricing environment to enable

on water conservation and water demand management

mine water treatment projects to be replicated and, ulti-

initiatives, to reduce Eskom s water usage by 2030 and

mately, upscaled to include a number of adjacent mines.

improve the water consumption rates to produce a kWh

One solution is to introduce regional treatment facilities

of electricity, while ensuring zero harm and protection

that benefit more than one mine and also generate suf-

of our water resources. Eskom has a major role to play in

ficient water for sale to other water users in need, with a

sustainability functions, and we also focus heavily on water

central disposal facility for the waste produced. The major

stewardship initiatives. We are participating and collabo-

benefit in a water-scarce catchment such as the Olifants is

rating in a number of partnerships with government and

to offset and minimise the freshwater use by using treated

the private sector in addressing some of these challenges.

mine water.

In a water-scarce country that is still very reliant on

Researching and piloting different types of generation

electricity produced from coal-fired power stations,

technologies and cooling systems to reduce water

water issues are critical to not only the functioning of Eskom s operations, but the broader community and the environment. One of the biggest challenges facing Eskom is that of water quality. Excess mine water that is not properly treated and discharged, as well as decant from abandoned and ownerless mines, has an impact on water resource quality and contributes to the pollution of our water resources. Poor management and infrastructure problems exacerbate this, and Eskom is left to foot the bill of treatment of poorer quality water it abstracts from various dams and then has to deal with the disposal of the waste residue, eventually translating to the cost of producing electricity.

Eskom is working very closely with its coal suppliers to ensure that the mines are compliant with environmental

“Part of the vision is to develop sustainable long-term solutions to water supply challenges in SA as well as the optimum management of water within Eskom’s operations and facilities.” Nandha Govender, general manager of water and environmental operations

er and water licensing conditions and to manage water

ongoing effort at Eskom. This includes dry-cooling and fluidised-bed combustion

(FBC)

technology

and dry-ashing systems. The new coal-fired

power

stations

under

construction, that is, Medupi and Kusile, will feature some of the biggest dry-cooling installations in the world.

Dry cooling is the process where the system uses air instead of water to cool the steam exiting a turbine.

Dry-cooled systems do not use water and can decrease total power plant water consumption by more

effectively during operations and closure of these mines.

than 90%. There are, however, trade-offs to

n Several other factors contribute to this situation. When

8

consumption and usage are an

these water savings, namely, higher capital costs

o municipal effluent gets into a river, it is normally due to

and lower thermal efficiencies. In power plants,

ageing infrastructure and the lack of maintenance of thatt

lower thermal efficiencies mean that more fuel

d infrastructure or that the infrastructure is not designed

is needed per unit of electricity produced, which

or upgraded timeously to treat the current volumes of

can, in turn, lead to higher air pollution and envi-

y, effluent. This in turn is exacerbated by a lack of capacity,

ronmental impacts from mining, processing and

especially within smaller municipalities.

transporting the fuel.

pEskom has partnerships in place with its major coal sup-

Govender says: The major advantage is that

e pliers. A joint initiative agreement is in place, and we are

dry-cooled units can use up to 15 times less water

JANUARY/FEBRUARY 2014

HOT SEAT

water use need pics

than conventional wet-cooled units. Eskom has made a policy decision to implement dry-cooling technology at all new coal-fired power plant, and thus, Medupi and Kusile

Medupi, a new dry-cooled coal fired power station

will be equipped with dry-cooling technology. We are

resources by diversifying its water mix to include treated effluent and mine water, raise awareness of water-related issues within Eskom and change behaviour to save water and electricity.

living in a water-scarce country and the challenge lies in

The main criteria for the WCWDM award ran across three

utilising our water resources efficiently through technolo-

categories, namely:

gies such as dry cooling.

• reducing water usage in own operations

At the other end of the spectrum lies fluidised-bed

• innovation, technology and management processes

combustion (FBC). This is a combustion technology where

• research and development around water issues.

fluidised beds suspend solid fuels in upward-blowing

Govender continues:

jets of air during the combustion process. The result is a

concern to Eskom, as this has a direct impact on water

turbulent mixing of gas and solids. The tumbling action,

resources, and Eskom s Business Continuity Plans focus

much like a bubbling fluid, provides effective chemical

on the company s resilience and response to events

reactions and heat transfer. FBC is well suited to burning

such as flooding and drought. Other criteria are broader

fuels that are difficult to ignite, such as petroleum coke

and include societal and environmental impacts and

and anthracite, low-quality fuels such as high ash coals

how these contribute to long-term sustainability and

and coal mine wastes, and fuels with highly variable heat

forms part of Eskom s Water Management Policy and

content, including biomass and fuel mixtures.

Govender concurs: What is exciting about FBC technology is that it also minimises water usage and can use water of a poorer quality. Both these technologies will reduce Eskom s water and carbon footprint.

Diversifying the energy mix by utilising renewables such as wind and solar, open-cycle gas turbines, and nuclear energy on the coast, as well as importing hydroelectricity, will further reduce Eskom s water footprint. Eskom is also targeting energy efficiency and conservation to reduce its water footprint. By reducing electricity usage, it also reduces the amount of water used to produce electricity.

Eskom recently received a silver commendation during the Department of Water Affairs 2013 Water Conservation and Water Demand Management Sector Awards

Climate change is of particular

commitments to the UN CEO Water Mandate principles framework, including developing skills and capacity to deal with challenges facing Eskom and the catchments in which it operates.

This is the first time that the Eskom has been given recognition for its work around water management, and this means a tremendous amount on the back of a very difficult year for the parastatal. We achieved this accolade on the success of our WCWDM Programme. We will continue to focus on partnerships among all sectors and lead work towards the World Economic Forum Water Resources 2030 goal of reducing the water resources gap

We want to bring awareness to our employees, our

in South Africa by 2030. Eskom will continue to focus on

customers and the public on the importance of water

managing our water resources sustainably by becoming

through our Water Conservation and Water Demand

better water stewards, concludes Govender.

Management (WCWDM) Programme and Eskom s 49M campaign. The WCWDM campaign has as its slogan Saving water to power the nation , with the main objectives of reducing Eskom s water consumption to achieve the set targets, reduce Eskom s reliance on freshwater

JANUARY/FEBRUARY 2014

9

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LABORATORIES

MUNICIPAL WASTEWATER

Processes and challenges of analytical services There are several factors that need to be considered when operating a municipal wastewater works, including laboratory testing requirements to assist in understanding the efficiency of the treatment process.

HE DECISION ON THE CHOICE of the wastewa-

5. The final process in wastewater treatment is disin-

ter treatment practice depends on the quality of

fection. Chlorination is the most common means of

T

the incoming raw water, the required quality of

disinfecting wastewater.

the final treated water and the economic resourc-

Process control sampling at the treatment plant com-

es available for the operating costs of the treatment plant.

prises on-site tests carried out on a regular basis at the

The requirements for laboratory testing play a significant role in the operation and maintenance of the plant.

Both compliance and process samples are taken throughout the works at specific sampling points. This is essential to trend the process efficiencies and evaluate the compliance of the plant to general effluent standards.

Domestic wastewater treatment processes can be broadly classified in one of five categories as follows.

The requirements for laboratory testing play a significant role in the operation and maintenance of the plant

1. Physical separation of solids from the flow by screening

works. These tests include pH, total dissolved solids, dissolved oxygen, conductivity, chlorine and half-hour sludge settlements.

Other

important

process

control

considerations in secondary treatment are temperature, pressure and salinity, which affect the saturation concentrations between the gas and liquid phase

and settling out heavy inert grit.

for both aerobic and anaerobic digestion. Treatment

2. Primary treatment follows this pretreatment, which is

plants in South Africa are moving away from the mundane

also a physical removal process. Gravity settling in pri-

manual operating systems of running the works to more

mary clarifiers removes some of the suspended organic material and most of the total suspended solids.

3. Secondary treatment processes are biological processes that use bacteria and other microorganisms to break-

automated processes. Operational sensors and testing

Audaine Moonsamy, sales consultant

probes at key points throughout the treatment process allows for fine-tuning and conditioning of valves, aerators and dosing levels. On-site testing equipment must also be

down the organic material that was not removed in

encased due to the erratic nature of incoming load. It is

primary clarification. Secondary treatment processes

crucial that the equipment used on site is calibrated and

include trickling filters and different kinds of activated

monitored for any malfunctions as it plays a vital role in

sludge processes.

optimising the works.

4. Tertiary treatment processes follow secondary treatment. Tertiary filter processes can be used to remove

The importance of testing

suspended solids. Nutrient removal processes are also

Compliance sampling at the wastewater works is under-

considered to be tertiary treatment processes.

taken by the laboratory using the utmost care to maintain

JANUARY/FEBRUARY 2014

11

LABORATORIES testing for oxygen absorbed as it masks the desired titration end point colour.

3. When conducting the chlorine test on-site using the conventional colorimetric method, chlorine in high concentrations inhibits the reagent from producing a distinct colour change, as the reagent is oxidised almost immediately. Dilutions must be conducted in order to accomplish accurate results.

4. Analysis of elemental metals in wastewater using inductively coupled plasma mass spectrometry (ICP-MS) has made significant improvements in time management, cost efficiency and accuracy of results. The ICP-MS is a type of mass spectrometry capable of detecting elemental metals and several non-metals at concentrations as low as one part per trillion (ppt). Compared to atomic absorption techniques, ICP-MS has greater speed, precision and sensitivity. In addition, the sample the integrity of the samples during sampling and transportation to the laboratory. Samples are taken at different

Compliance sampling

preparation is relatively simple and quick. There are many aspects of maintenance that need to be incorporated by daily, weekly and annual procedures where the

stages in the wastewater treatment process to understand

frequency of maintenance is typically determined by

the operational efficiencies and compliance to the general

the sample volumes and increasing run time that the

effluent standards.

When sampling for analysis of microbiological constituents, it is also very important to adhere to the aseptic sampling procedures. The preservation period of the samples, the correct sampling containers, as well as the appropriate neutralising agent in the sample bottle is imperative in the final determination of these bacteriological components.

Sample sites for this compliance sampling phase includes, but is not limited to, samples from the following process points: • incoming raw water

Flow injection analysis offers many advantages over traditional wet chemistry testing for the determination of nutrients

• settling tanks

Flow injection analysis offers many advantages over traditional wet chemistry testing for the determination of nutrients. The procedure is inexpensive and quick, often producing results within very reasonable turnaround times. The equipment is computer compatible, providing quicker analysis while limiting data entry errors more prevalent in manual testing.

Constraints

in

these

automated

methods

include the sample matrix and samples with an elevated conductivity. This results in additional

• mixed liquor

sample preparation that may include, but is not limited to,

• final effluent.

sample pre-treatment or dilution before analysis.

The results of laboratory testing of the final effluent sam-

5. The COD test is commonly used to indirectly measure

ple are used to determine compliance with the general

the concentration of organic compounds in water, mak-

effluent standards.

ing the test a useful measure of water quality in waste-

Laboratory testing in each instance above may comprise

water management. Some samples contain high levels

a combination of the following tests: ammonia, chemical

of oxidisable inorganic materials, which may interfere

oxygen demand (COD), chloride, conductivity, E. coli, free

with the determination of COD. Chloride is often the

chlorine, heavy metals (where requested), nitrate/nitrite,

most prevalent source of interference. To overcome this

oil and grease, orthophosphate, oxygen absorbed, pH at

challenge, the sample is treated with mercuric sulphate

25° C, suspended solids at 105° C and total alkalinity.

prior to the addition of other reagents to eliminate chlo-

Some of the analytical challenges facing the laboratory

ride interference.

when undertaking testing of wastewater samples includes

These laboratory challenges are overcome with effective

the following:

laboratory management through the implementation

1. Constituents in the incoming raw water, such as oils,

of a suitable quality management system that addresses

fats and inorganic substances that have passed through

the following:

the screens in the treatment process, which affect the

• administrative controls

laboratory analysis. Sample preparation such as filtering

• staff competence

of the samples to eliminate the coarse suspended or

• method development and validation

floating matter will facilitate a more accurate result.

• calibration of equipment

2. During the tertiary stage of treatment, all factors that

12

instrument is subjected to.

• sampling and handling of the sample at the laboratory.

make up the effluent for discharge have to be con-

Talbot & Talbot offers scientifically engineered solutions

sidered. Chlorine either in liquid, solid or the gaseous

that cater to the requirements of operating and manag-

phase is used for final disinfection. High concentrations

ing wastewater treatment plants with the support of an

of this disinfectant and oxidising agent can cause matrix

accredited laboratory in the Talbot Laboratories division

interference in certain test procedures. For example

of the company. The laboratory is accredited to the ISO

chlorine obscures the end point titration values when

17025 standard for water and wastewater testing.

JANUARY/FEBRUARY 2014

LABORATORIES

LEADING THE WAY

SA’s expertise in water analysis It is often said that when one door closes, another one opens. This is especially true in the case of the Mpumamanzi Group, writes Maryke Foulds.

T

HE COMPANY IS THE BRAINCHILD of Thusi Motsepe, analytical chemist, and founder member Rita Botha, who in 2001 decided to form their own laboratory to provide services

to the water sector.

LEFT The water laboratory RIGHT One of Mapumamanzi’s students

black professional graduates ranging from analytical chemists, process technologists, chemical engineers, environmental scientists, geohydrologist and microbiologists. Mpumamanzi is passionate about equitable employment. The Watercare Division in Cape Town is

According to Tony Bowers, who bought into the

run by paraplegic Caroline Bowers, and her expertise

company in 2008, it was difficult getting the company

and dedication has shown all of us that disabled peo-

established. Growing it was even more onerous, but

ple are capable of achieving success if given the space

through funding from the Department of Trade and

to develop and grow.

Industry (dti) and the Small Enterprise Development

As a fully fledged black owned company there are still

Agency (Seda) they are now up and running, and pro-

some challenges, says Bowers. The biggest one facing

viding a crucial service to the water industry.

emerging black professional companies is sustainabil-

Mpumamanzi Laboratory Services was first established in 2001 by Motsepe and Botha, who had previously worked for SA Cyanamid Laboratory. When it closed its doors and withdrew from South Africa, these two entrepreneurs decided to open their own

The primary objective of the business is water and wastewater analysis

ity. A number of factors contribute to this, including too-high salary demands by professionals; lack of skills within designated groupings; strict legislative control in terms of

facility to provide services to the water sector. I joined

quality standards, which requires huge administrative

the company in 2008, having bought Botha out.

input; changing mind sets in terms of the capabilities

Initially, we only focused on the analysis of water and

of black water professionals and competing with

wastewater samples, but have since grown to include

multi-national and established companies with huge

a diverse range of clients, including the mining sector.

financial resources.

Work is focused around four divisions: Laboratory and

With its head office situated in Steve Tshwete

Environment, Water Engineering, Geohydrology and

(Middelburg) in Mpumalanga, it recently procured

Mining, and Watercare.

a state-of-the-art laboratory from BHP Billiton and

The primary objective of the business is water and

the building also houses all divisions except for

wastewater analysis. Initial development was slow due

Watercare, which is situated in the Western Cape. The

to the high cost and maintenance of the equipment.

Laboratory & Environmental Division concentrates

The intervention of Seda was quite substantial and this

on water and wastewater analyses as well as coal

contributed to Mpumamanzi s turnaround. Employees

analysis. Bowers continues:

have increased from six in 2008 to 20 in 2013. 80% are

the most modern equipment and we are currently in

JANUARY/FEBRUARY 2014

Our laboratory houses

13

LABORATORIES

MPUMAMANZI LABORATORY SERVICES CC

the process of preparing for our SANAS accreditation. We are confident that this process will be finalised by July 2014. This division is managed by Wadzanai Matowanyika, who holds an MSc in Environmental Science from Wits University. The Geohydrology & Mining Division concentrates on borehole water monitoring and assessment of underground water as-

Showcasing the best of African skills in water

sociated with the mining sector. This division is managed by

Contributing to the excellence of water quality management in South Africa

Mbinze Akwansioge, who has an MSc in Geohydrology from

Mpumamanzi is the fastest growing wholly-owned – and black managed Water Laboratory in South Africa. Mpumamanzi is supported by SEDA in its development and certification towards a fully-fledged SANAS Laboratory.

engineering projects associated with the application of tech-

Mpumamanzi participates and maintains an acceptable “z” score in terms of both SABS- and NLA performance proficiency schemes.

Our laboratory has a staff compliment of fourteen (14) supported by a highly professional team of comprising of Analytical Chemists, Water Technologist, Environmentalist, Chemical Engineer, Microbiologist and Professional Office Manager.

parency in terms of the Blue Drop Certification programme,

the University of the Free State.

The Water Engineering Division concentrates on all water nologies to improve water quality and minimising bacterial risk. The standard of water in South Africa is very high and based on journal reports and South African s level of transSouth Africa is one of the few countries in the world where people

The group is wholly owned, professionally managed and operated black company

In addition to our laboratory functions we also serve as specialist advisors for: the Blue – and Green Drop Compliances; Environmental issues, Analyses and Interpretation of Water analytical data; Evaluation of applied water treatment chemicals; Asset Management; Serious microbial and viral failures.

can

drink

water directly from the tap. This division is headed by July

Mngidi,

has

a

who

Chemical

Engineering Degree from the Cape Town

University of Technology. The Engineering Division is responsible for a range of water engineering products, varying from the optimisation of water and sewage works, the inspection and auditing of water and sewage works, trouble shooting of waterworks, auditing for blue and green drop compliances and responding to crises in terms of bacterial contamination in reservoirs, JoJo tanks, dams, etc.

The division has a unique chemical disinfectant and equipment that is capable of accessing remote reservoirs and systems that are contaminated. We also clean and certify potable water tanks. Contaminated systems are decontaminated and the water is then certified to drink. The division has been recently called out to successfully decontaminate remote reservoirs in the North West and Mpumalanga.

It has also been appointed by Eskom to monitor the water quality of over 100 JoJo tanks at the Kusile site on a daily basis. Despite the risk associated with water quality management in a dusty area, Eskom has not recorded a single incident related to contamination since the project was implemented four years ago.

The Watercare Division concentrates on the supply of bulk water treatment chemicals to municipalities primarily in the Western Cape region. The chemicals are sourced from various

BBBEE Status: Level 1 Mpumamanzi Laboratory Centre, 6 Newton Rd, Industrial Area, Ex 11, Middelburg, Mpumalanga, 1055 GPS: 250 47” 7.57’ S and 290 29’ 33.62’ E za.linkedin.com/pub/dir/Antonio/Bowers Tel (013) 246 2633/35/36/49 | Fax (013) 246 2692 eFax (086) 629 7360 Senior Partners: Tony Bowers B.Tech, SFWISA: (084) 505 2171 Thusi Motsepe Nat. Dip Anal Chem: (082) 372 8434

14

JANUARY/FEBRUARY 2014

LABORATORIES manufacturers and supplied in bulk to various municipalities and the private sector.

Focusing largely on municipalities, water service institutes, mining houses and the wet industry, it currently operates in the Mpumalanga region, but hopes to expand to the other provinces, particularly the Western Cape, Free State, Eastern Cape and Northern Cape.

When asked what the biggest challenges are facing the water sector, Bowers replies: I would say poorly managed and operated sewage works primarily due to the lack of professional trained process controllers.

However, we are confident that with the publication of the revised R2834, which regulates the management of waterworks would change the Cinderella status of sewage works forever. The outsourcing of wastewater services to unskilled personnel does not help the sector.

Mpumamanzi in a nutshell The group is wholly owned, professionally managed and operated black company. Its buy-in of women stands at 65% and is managed by Motsepe, who is group manager, and Bowers, who is group manager of the legal and strategic departments. The group recently entered the market of coal analysis and is now

ABOVE July Mngidi

equipment to conduct both water and coal analyses.

OPPOSITE Microbiologist Rodney Motsusi

and knowledge transfer of students; however, it does

Mpumamanzi has the capacity to assist in the training not have the funding to accommodate the large number of unemployed graduates who need to gain

looking for an international company to partner with

experience in this sector. Mpumamanzi will provide the

in this highly competitive environment. It recently

transfer of skills freely if there are companies willing to

procured a 15 000 m2 premises with state-of-the-art

sponsor students.

15

JANUARY/FEBRUARY 2014

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WATER TREATMENT

RESEARCH UPDATE

Stellenbosch rivers still in The levels of human excrement and disease-causing pathogens in rivers around Stellenbosch are unacceptable and unsanitary. People who use the rivers for sport and recreation stand a chance of contracting diseases such as diarrhoea, food poisoning and various types of infections.

disease-causing pathogens are able to attach to plant tissue. These can be harmful to humans if the produce is eaten raw and untreated.

According to the South African Department of Water Affairs (DWA) and the World Health Organisation (WHO), levels of less than 1 000 faecal coliforms (bacteria that are present in the intestines of humans and animals) per 100 ml sample of water is considered safe to use for irrigation.

However, higher concentrations of faecal indicators in the Plankenbrug and Mosselbank were found in more than 70% of the samples, and to a lesser extent also in the Eerste and Berg Rivers.

HE WATER OF THE Eerste and Plankenbrug

The Stellenbosch rivers clearly do not meet the min-

rivers regularly do not meet international or

imum guidelines of the WHO or DWA, and are therefore

national standards for the safe irrigation of fresh

not safe to use at all ‒ not for irrigation, consumption,

produce. These are the findings of the first thor-

recreation nor sports, says Britz. There is a high risk of

ough baseline study in more than a decade to quantify the

exposure to human pathogens when water from these

extremely poor microbial state of the two rivers. The study,

rivers is used to irrigate produce that is consumed raw or

published in the Water SA journal, was led by Prof Trevor

without any further processing steps.

T

Britz of the Department of Food Sciences at Stellenbosch

Do not swim in the rivers or drink untreated water, and

University. It focused on the impacts that the polluted

if you are eating fruit or vegetables irrigated from these

rivers have on food safety and human health.

rivers make sure you wash it properly, preferably with a

Britz s research team monitored the types of microbes

mild disinfectant like Miltons added to the water.

and chemicals in the Plankenbrug and Eerste rivers over more than three years across different seasons. The rivers

What was found?

pass through Stellenbosch and are used both upstream

• The researchers reported acceptable levels for irrigation

and downstream of the town to irrigate grapes, pears, citrus

purposes of physicochemical properties such as temperature, acidity and alkalinity levels.

fruit, lettuce, strawberries, peppers, herbs and green beans,

• However, microbial tests show that human excrement

among others, especially during the summer months.

in particular is severely polluting the rivers.

Samples were taken once a month on a Monday morning

• High concentrations of faecal indicators in the

for 42 months, from September 2007 to March 2011.

Plankenbrug and Mosselbank rivers were present in

A high variety and extreme levels of waterborne faecal

more than 70% of the samples, and to a lesser extent in

bacteria, protozoa and viruses were found in the water as well as on produce irrigated from the rivers. Various

16

The Eerste River

the Eerste and Berg Rivers.

JANUARY/FEBRUARY 2014

WATER TREATMENT

dire straits?

• Concentrations of more than 1 million microbes per 100 ml of water were often measured. According to the WHO and DWA guidelines, it points to severe unsanitary conditions.

• More than 30 types of bacteria and 180 phenotypic variations of the bacterium E.coli were found. E. coli generally found in human and animal guts and its presence in a sample means that human or animal faeces is present in the water.

• Other potential pathogens such as Staphylococcus (food poisoning), Klebsiella (respiratory infections), Listeria (listeria infections) and Salmonella (food poisoning, diarrhoea or kidney failure) were also found.

The Kayamandi informal settlement, sewage pipe leaks and the Plankenbrug industrial areas were earmarked as continuous sources of pollution.

Even though the study showed slightly lower measurements than that of a 2004 community health study by Dr Jo Barnes, also of Stellenbosch University, the results are still extremely worrying.

The high counts of Salmonella on their own pose a seri-

Minister of Water and Environment Rejoice Mabudafhasi taking a sample from the Eerste River Source: WRC

fresh produce set by the European Union, nor the health standards of local authorities or the WHO. The national study included rivers such as the Eerste, Plankenbrug, Mosselbank and the Berg rivers in the Western Cape, the Baynespruit River in KwaZulu-Natal, the Mutshedzi River in Limpopo, the irrigation canal from Loskop Dam and the Olifants and Wilge rivers in Mpumalanga, as well as the Skeerpoort, Moses and Klip

ous risk of potential food poisoning, since some residenc-

rivers in North West. These rivers are regularly used to

es on the banks of the Plankenbrug and Eerste Rivers draw

irrigate agricultural produce.

water for gardening or household purposes, Britz says.

The overall findings of the national study were:

Pollution levels were found to be constantly high

• The microbial results showed high concentrations of fae-

throughout the year, irrespective of season or water

cal microorganisms with concentrations reaching 10 mil-

temperature. Extremely high levels were even noted

lion cells and indicate unsanitary conditions. This is ten

after heavy winter rainfalls. This is probably because

thousand times higher than the allowed,

of increased run-off from the informal settlements or churning up by stormwater of bacteria trapped in the river sediment, he notes.

Certain human-based pathogens were also measured in boreholes, which might indicate that underground water sources have now also become contaminated because of seepage from the rivers.

Based on the extremely high levels of contamination shown in the water and on irrigated produce, it is time to seriously put measures in place to prevent serious problems for our agricultural sector and the local population, says Dr Gerhard Backeberg of the Water Research Commission (WRC).

Part of nationwide study The Stellenbosch findings are part of a nationwide study, the results of which were released in July in a four-part report documenting the extent of pollution in many South African rivers that are used for irrigation purposes and the impact this has on food safety and human health.

The national study was led by food scientist Britz and colleagues from Stellenbosch University, the University of Pretoria, the University of KwaZulu-Natal and the University of Venda. Funded by the South African WRC

ABOUT THE NATIONAL STUDY The nationwide study was commissioned in 2007 by the Water Research Commission and the Department of Agriculture, Forestry and Fisheries. It was edited by Prof Trevor Britz and Dr Gunnar Sigge of the Department of Food Science at Stellenbosch and compiled by food scientist Prof Elna Buys and medical virologist Prof Maureen Taylor of the University of Pretoria, microbiologists Prof Stefan Schmidt of the University of KwaZulu-Natal and Prof Natasha Potgieter of the University of Venda.

Reference: Britz, TJ, Sigge GO (ed). Quantitative Investigation into the Link between Irrigation Water Quality and Food Safety, Vol 1-4, WRC Report No. 1773/1/12 The full report can be downloaded at www.wrc.org.za

safe levels set by the WHO and DWA. • In particular, the E. coli concentrations in most cases exceeded the maximum acceptable guidelines of the WHO and DWA. • Other potential pathogens including Staphylococcus, Klebsiella, Listeria and Salmonella,

intestinal

Enterococcus,

faecal coliforms, commensal and diarrhoeagenic E. coli, diarrhoea-causing viruses (NoV GI and GII, and HAV), Cryptosporidium oocysts and Giardia cysts were also measured in many of the rivers. One or more such enteric virus was found in 18% of river water samples and 9% of irrigation canal samples.

The results of the national study clearly show how unacceptable the standard of many of our rivers are, says Britz. There is a high risk of exposure to human pathogens when water from the studied rivers is used to irrigate produce that is consumed raw or without any further processing steps.

and the Department of Agriculture, Forestry and Fisheries, the extensive research project of almost R5 million was launched in 2007 amid growing concerns that South Africa s river water no longer meets exports standards for

The article was written by Prof Trevor Britz and Dr Gunnar Sigge of the Stellenbosch University Department of Food Science, along with postgraduate students in food science Nicola Huisamen, Tshepo Kikine, Marijke Lötter, postdoctoral associate Dr CorneLamprecht and statistician Prof Martin Kidd.

JANUARY/FEBRUARY 2014

17

WATER TREATMENT

SWARTLAND

Membrane bioreactor solves Malmesbury’s water challenges The Malmesbury wastewater treatment works (WWTW) is situated at the southwest end of this fast-growing community.

It treats both domestic and industrial wastewater and discharges the treated effluent into the Diep River.

The final effluent, without further treatment, even satisfies the stringent requirements for European bathwater.

Implementation of the MBR plant at Malmesbury WWTW The site of the treatment works is located in Diep River, which flows into the Milnerton Lagoon and ultimately into the Atlantic Ocean. Apart from the nutrient removal required, the WWTW historically also had problems with sludge that washed from the systems and into the river during high flow.

A

NEW HYBRID membrane bioreactor, which is designed to treat an average flow of 10 000 m3/ day of wastewater, was recently installed at the plant. The construction of the activated sludge

ABOVE The bioreactor during construction

Various options for upgrading the works had been presented. The municipality decided on MBR technology primarily for the following reasons: • If the treatment works was to be upgraded using con-

plant is allowing the Swartland Municipality to set new

ventional activated sludge technology, the maximum

standards in the treatment of wastewater.

treatment capacity that could be accommodated on the current site would have been limited to about

18

Membrane filtration

15 Mℓ/d. According to current flow forecasts, this

The use of membrane filtration in municipal wastewater

meant that an alternative site for a treatment works

treatment has significant beneficial impacts on the treat-

should have been identified within the next decade.

ment process. Despite the reduced footprint of the works,

Using MBR technology, the treatment capacity that

the treated wastewater achieves a quality that cannot be

could be accommodated on the current site could be

attained with a conventional wastewater treatment works.

increased two- to threefold.

JANUARY/FEBRUARY 2014

WATER TREATMENT

• With an MBR plant, the risks of solids carry-over into the environment are virtually eliminated.

• The quality of the effluent will be such that disinfection will normally not be required.

In an MBR plant, the required membrane area is one of the major factors that determine the cost of the treatment works. In areas such as the Western Cape, where the wet weather peak flow can last for extended periods, the required membrane area is directly related to the hydraulic load on the system. If the peak hydraulic load on the plant could be reduced, it would have a direct impact on the capital cost of the plant.

Various means of incorporating the existing Pasveer Ditch basin, as well as the downstream sedimentation tanks, into the upgraded works were considered during the design phase. It was eventually decided to operate the existing biological reactor in parallel with the MBR plant, allowing only the peak flow to effectively flow through the sedimentation tank of the existing works.

The old sewage works

from the works via the membrane train/units. When the flow to the works exceeds the design peak dry weather flow rate, excess flow flows to the secondary

The treatment work consists of an inlet works with

sedimentation tank.

dual screening (50 mm and 5 mm) and grit removal.

There is a third, 1.5 mm fine screen at the bioreactor.

The bioreactor has an UCT-type configuration with four

The membrane activate sludge process

dedicated membrane tanks. A treated wastewater and

Once a bacterium has treated the wastewater biologi-

dewatering units are also provided. Several new pump

cally, it is filtered through the pores of the membranes.

stations were constructed as part of the project. The bi-

With a pore diameter of less than a thousandth of a

oreactors have continuous inflow, but are intermittently

millimetre, these filters retain not only all solid matter,

aerated to achieve nitrogen removal.

There are four membrane tanks and permeate pumps are used to extract treated wastewater through the membrane.

The plant is provided with six positive displacement blowers. Three are for fine bubble diffused aeration and three for coarse scouring of the membranes (all arranged in a two duty, one standby mode).

Each of the four MBR tanks is sized for five membrane units (or packs), but only four have been installed in

In an MBR plant, the required membrane area is one of the major factors that determine the cost of the treatment works

but also virus and pathogenic agents.

At the same time, the bacteria that are responsible for the biological wastewater treatment also remain in the reactor. Since the system makes use of a physical barrier and not sedimentation tanks to separate the sludge from the treated water, the sludge concentration in the MBR systems can be much more concentrated

than in a conventional treatment works.

each tank, with the remainder of the membrane units available for later installation. The current available

This means that the bioreactor s area is approximately

membrane capacity is sufficient for hydraulic design

a third of the size of those to be found in normal con-

capacity of twice the average dry weather flow (ADWF),

ventional wastewater treatment works. In the case of

with an allowance to ultimately increase total peak

Malmesbury WWTW, the membranes in the bioreactors

capacity of the MBR plant by a further 25% of the ADWF with additional membrane units.

Upgraded Malmesbury WWTW flow description

The bioreactor where sewage is treated

are in the form of submerged membranes in the bioreactors and are thus integrated into the biological treatment stage. The membrane filters comprises individual

All flow arriving at the works is split at the end of the inlet works (at the outlet chamber) in a ratio of 85:15 up to a total flow of 20 Mℓ/day, i.e. peak dry water flow of which the smaller fraction is routed to the existing treatment works. All inflow up to a total of 20 Mℓ/day diverted to the existing Pasveer Ditch is pumped back to the MBR plant and all treated effluent from the plant will pass through the membranes. When the total flow into the work exceeds 29 Mℓ/day, the existing clarifiers will become operational and be utilised to settle sludge from all flow more than 20 Mℓ/day. This configuration ensures that, up to the design peak, dry weather flow, all treated with effluent from the upgraded works, flows

JANUARY/FEBRUARY 2014

19

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WATER TREATMENT The pump room, with permeate pumps on the right

far the efficiency of normal sand filtration.

The construction of the membrane plant had minimal impact to the existing plant. The work to convert the existing system into the new configuration was scheduled to start in the low season to minimise the impact of the operation of the current pant. To allow the plant to continue treating wastewater, the MBR plant was commissioned in stages. This allowed the engineers to start hydraulic testing of equipment and commissioning the plant without major impacts on the rest of the treatment units.

modules that are equipped with a large number of fine,

In conclusion, the upgrading of the wastewater treat-

spaghetti-like hollow fibres. The actual filtering pro-

ment plant to a MBR system was a success satisfying

cess takes place on the outer surface of these fibres.

all the objectives set at the planning stage. By utilising

The treated wastewater is drawn through the walls

the existing infrastructure and keeping the existing an-

of the hollow fibres using a slight suction force. The

aerobic digester and Pasveer Ditch tanks, a significant

water, after passing through the membrane is called

cost saving was realised. The upgrade was carried out

permeate. A blockage of the filter is countered through

in a stepwise process and thus interruption to the op-

regular backwashing using the permeate. In addition,

eration of the existing plant was minimised. The system

air is blown into the wastewater below the filter, which

is designed to accommodate seasonal flow variation

then flows over the surface of the filter and sets the

and provide operational flexibility and energy saving.

individual fibres in an oscillating motion. Particles and

The upgrade increases the plant hydraulic capacity to

solid matter that adhere to the surface of the filters are

20 Mâ„“/day, while achieving the effluent requirements

loosened and washed off.

and puts the plant in a position to serve its purpose into

Membrane filtration makes smaller tank volumes pos-

the future.

sible, replaces classical conventional secondary setting tanks, obviates the need for disinfection and exceeds by

Information source: Swartland Municipality & Aurecon

21

JANUARY/FEBRUARY 2014

The Intelligent Choice With a solid track record spanning over half a century, GIBB has established itself as a partner of choice. Backed by a Level 2 BBBEE rating, GIBB provides engineering solutions to a diverse range of markets across the African continent.

1FPQMF t &YQFSUJTF t &YDFMMFODF marketing@gibb.co.za | www.gibb.co.za | +27 11 519 4600

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MEDIA

WATER TREATMENT

Water infrastructure overhaul continues To boost the town’s sewage treatment capacity, the Walvis Bay Municipality recently contracted Aqua Services & Engineering (ASE), a subsidiary of the global Veolia Water Solutions & Technologies, to upgrade existing stone-media biofilters in the company’s flagship trickling filter technology at the local sewage treatment works.

HIS UPGRADE, valued approximately at R15 mil-

T

lion, will significantly improve the quality of final

effluent from this portion of treatment, amounting to about 6.5 Mℓ/day. Existing civil works in the form

of the old trickling filters superstructures were rejuvenated to house the new generation treatment process.

It s the first time in Namibia that the new-generation

An aerial view of the plant showing the new trickling filter media [centre] and the existing stone media [right]

construction three metres below ground level, ASE faced a unique challenge to overcome the presence of groundwater and its high salinity. Normally, we find groundwater to be relatively fresh, but because Walvis Bay is a coastal town, the groundwater level is very shallow and the water very salty, says Stöck.

Due to this and the proximity of existing structures, ASE

trickling filter technology was used to replace old stone

decided to use sheet piling and dewatering pumps to

filter media, says Chris Stöck, managing director at ASE.

excavate for the pump station. The concrete pump station

Trickling filters give far fewer operational problems

was then constructed in situ by conventional methods.

and, with regard to blockages and ponding, are decades

ASE also supplied and installed new stainless steel biofilter

more advanced.

distribution arms to replace the existing biofilter arms,

At full operation, the new polypropylene (PP) media will

which were already in disrepair and not sized for the in-

host the micro-organisms that, in Stage One, remove car-

creased recirculation rate.

bonaceous material such as chemical oxygen demand and

The newly constructed plant and pump station is cur-

biochemical oxygen demand. In Stage Two, the micro-or-

rently receiving in excess of 500 m³/hour of raw sewage

ganisms perform nitrification. The effluent is continuously

at peak flows, and the total continuous recirculation flow

recirculated through the PP media at a high rate, increas-

through the filter media is approximately 1 240 m³/hour.

ing the biofilters aeration by three times which, in turn,

The system is undergoing performance testing to ensure

multiplies the biological treatment s efficacy three-fold.

effluent quality.

With an effective surface area of up to 150 m² per cubic

Walvis Bay is the latest of a series of towns in Namibia

metre, the media is specially designed to facilitate fast

to kick-start a large-scale water infrastructure upgrade,

growth of microorganisms on their surfaces, while the large passage size and cross-flow patterns effectively prevent blockages and ponding.

ASE upgraded two of the three existing biofilters by

Water exiting the trickling filter digestion process

following the construction of a new Swakopmund wastewater treatment plant, for which ASE supplied mechanical works, and an upgrade to the Katima Mulilo plant that will feed drinking water into the Caprivi pipe system.

packing the larger 45 m diameter filter to heights of 3.6 m with new PP media that s designed specifically for stage one processing. The smaller 30 m diameter biofilter was packed 1.8 m high with PP media suitable for stage two processing, for an effective total of 7 000 m³ of PP filter media, says Stöck.

ASE imported the media as individual sheets and, once in place, welded them together using a specially imported German fusion welding machine. The assembled blocks are self-supporting and avoid creating unnecessary pressures on the biofilters side walls, making them ideal for use in older plants.

As part of the upgrade, ASE was also responsible for installing the plant s new recycle pump station. Specified for

JANUARY/FEBRUARY 2014

23

WATER TREATMENT

CHEMICAL SOLUTIONS

Serious about water Protea Chemicals officially opened its new Chlorine Plant and distribution facility on the existing Omnia site in Sasolburg on 23 October 2013. “This new facility was brought into production on budget and on time,” says Protea Chemicals’ project consultant, Peter Leopold.

T

HIS IS A MAJOR INVESTMENT FOR PROTEA ‒ one of the largest the company has made in a production facility. It is a demonstration of the company s commitment to the water treatment

industry in Southern Africa and complements its strong position in the production and marketing of other water treatment chemicals, says Leopold.

Chlorine is used primarily by water authorities and other drinking water producers for the cost-effective sanitisation of potable water. The supply of chlorine is therefore critical to the production of drinking water and the disinfection of sewage. There has, since 2004, been only one plant in South Africa that supplied packed chlorine to this

Approximately 95% of the world's drinking water is disinfected with chlorine

24

industry. The advent of a second supplier ‒ first conceived of in 2009 ‒ gives comfort to the market because there

JANUARY/FEBRUARY 2014

Providing watercare solutions for more than 30 years

For more information contact:

more than just a chemical supplier

Peter Leopold 011 709 8888 pleopold@proteachemicals.co.za

WATER TREATMENT

'HHS DQG DFWLYH

are now two plants that can supply its requirements, according to Leopold. This is a significant change in the strategic supply risk and will therefore have a significant impact. South Africa is also the dominant supplier to Southern Africa.

Chlorine still crucial In spite of the occasional attention attracted by other technologies, it remains true to say that more than 95% of the world s drinking water is disinfected with chlorine. There are no other technologies that provide all the technical and commercial advantages in one chemical or treatment process, explains Leopold.

This does not mean that the production and distribution of chlorine is without challenges. Chlorine is a hazardous chemical so there are ethical and legal aspects related to its safe

KROHNE WATERFLUX meets SANS1529-1:2006 fit for trade metrology – exceeds class D Specifications

production, handling and distribution. Our plant is a new greenfield site and all the equipment, tanks and cylinders are new.

We had no legacy of existing plant or technologies to which we had to adapt, so we were able to source the latest and best of everything, he explains. An example of this is evident in that every tank and cylinder has its own unique RFID tag, so Protea and its customers know where it is at all stages of its life.

As mentioned above, the RFID tracking is a significant innovation because these tanks and cylinders can end up in some really remote places and keeping track of them is a commer-

Direct subsurface installation of water meters? Now it’s possible with the WATERFLUX from KROHNE.

cial and legal requirement. In addition, we have a tank that is filled to a full 1 tonne net weight. This is 8% more than the commonly used mass and enables us to get better filling and transport economics.

WATERFLUX – the new electromagnetic water meter – enormously simplifies the integration of measurement technology in drinking water networks. Thanks to its permanent maintenance-free operation, an above-average service life of 25 years and the special subsurface installation coating, the WATERFLUX can be installed directly in the ground for applications not subject to custody transfer – and all this without a measuring chamber.

The bigger picture Protea is part of the Omnia Group and shares the vision of creating customer wealth by leveraging knowledge , explains Leopold. He adds that chlorine is also not a fundamentally easy product to use; it is hazardous, it is governed by rules and regulations, and it requires the support of a training and safety infrastructure. We believe that by applying our considerable expert knowledge in all these fields, we will be able to make the

The precisely acquired measurement and totaliser values can be conveniently read aboveground on the batteryoperated converter. Optionally, the data can be transmitted cyclically via any number of GSM mobile communications networks to a control system – even from remote areas.

purchase and use of chlorine a more cost-effective experience for our customers.

It is important to see that the chlorine project is a component of Protea s overall presence in water treatment chemicals. The group is already a major player in this industry and its capability

With minimum effort, you can set up an autonomous and fully remotely monitored metering point installed underground – one that is deep and active!

includes Zetachem s well-known production facilities in Durban and Cape Town, as well as major trading operations in all water treatment chemical commodities. The chlorine project therefore is another cornerstone in an already established business sector, concludes Leopold.

KROHNE – Water is our world.

A small section of the new chlorine facility at Omnia

Please see our website for more information ZZZ NURKQH FRP ZDWHUëX[ VHULHV KROHNE South Africa 8 Bushbuck Close Corporate Park South Randtjiespark, Midrand Tel.: +27 113141391 Fax: +27 113141681 Cell: +27 825563934 John Alexander j.alexander@krohne.com www.za.krohne.com

JANUARY/FEBRUARY 2014

25

WATER TREATMENT

DEGRÉMONT

Optimising sludge treatment The steady growth in the volume of sludge generated by water treatment is linked to both demographic changes and an increase in urban sprawl.

T

HIS

SITUATION

puts

additional

stresses

on municipalities and can lead to tighter constraints within the water industry.

Water&Sanitation Africa takes a look at what

Sludge treatment at La Feyssine in France

stabilisation and the recovery of green energy from the sludge in the form of biogas • thermal, mixed or solar drying • destruction through incineration.

Degrémont can offer the industry in terms of sludge management and treatment.

Sludge thickening

A key aspect to the treatment of sludge is to reduce

The thickening is the first step, often unavoidable,

its volume and transform it into a recoverable product.

and aims to reduce the volume of sludge from the

Degrémont Technologies, provider of high-performance

water system. It optimises the steps of conditioning,

water, wastewater and sludge treatment solutions,

stabilisation and dehydration by reducing the sizes

carefully evaluates each project with its design engi-

of structures and operating costs. Processes used are

neers and clients, and looks at the entire treatment line

the gravitational settling thickening (thickening static)

to find ways to improve the final destination of treated

and dynamic thickening (concentration implementing

sewage sludge.

dynamic energies).

According to Remy Jaffray of Degrémont, the compa-

26

ny s ultimate aim is to support local authorities in the

Sludge dewatering

management of sludge and by-products treatment,

Sludge resistance to filtration and compressibility factor

which must be recycled, eliminated or recovered. It

is often too high to ensure an optimal separation of

offers various technical solutions which implement

water and matter. In order to achieve this, one must

proprietary or licensed processes for:

first break the cohesion of colloidal mud and artificially

• sludge thickening and dewatering

increase particle size. This is the purpose of condi-

• sludge digestion ‒ in order to reduce its size and

tioning and the bases of satisfactory operation of the

increase dryness through dewatering, long term

dehydration plant, to achieve the objectives in terms

JANUARY/FEBRUARY 2014

WATER TREATMENT of final dryness, performance and operating costs. Two techniques are available, the first is dewatering by electro-osmosis and the second dewatering by pre-liming before centrifugation.

Sludge digestion generated by water treatment The process of anaerobic digestion offers numerous advantages. These range from the reduction of the sludge quantity, the increase of the dryness in dehydration, the long-term stabilisation leading to a reduction of the nuisances and the valuation in green energy by biogas production.

According to the quantity and nature of the sludge to be treated, various types of digestion can be utilised: • mesophilic digestion at 37° C • Digelis Smart ‒ mesophilic digestion and storage of integrated biogas • thermophilic digestion at 57° C • Digelis Duo ‒ thermophilic digestion at 57° C coupled with mesophilic digestion at 37° C • Digelis Turbo ‒ thermal hydrolysis combined with mesophilic digestion at 37° C.

A diagram of the sludge treatment process

This therefore constitutes an additional commitment for communities seeking sustainable energy solutions thereby contributing to the effective achievement of the objectives similar to those set by Europe, which can be beneficial to South Africa.

As a by-product of water treatment facilities, sludge can contain more than 95% water as well as suspended

Sludge drying Drying is necessary because of the limitations encountered in the mechanical dewatering of sludge.

Sludge has a specific behaviour that influences the thermal drying processes depending on the dryness reached. Generally, heat is transmitted in three ways: conduction, convection and radiation.

These heat transfer modes applied to sludge will result in different technologies including:

A key aspect to the treatment of sludge is to reduce its volume and transform it into a recoverable product

• thermal drying at low temperature by bands • drying the mixed combining a thin-layer dryer and a belt dryer with hot air • solar drying.

solids and other residue. Operators are committed to reducing these water volumes in order to more easily discharge and recover the sludge. To reduce the volume of sludge there are three broad categories of processes depending in the final dryness of sludge required, namely thickening, dewatering and drying.

Degrémont s Dehydris Twist is an innovative mechanical dewatering process holding

both filter press efficiency and centrifugal automaticity.

It combines advanced dewatering technology with ease of operation. Developed for drinking wastewater production and wastewater treatment, it is a multipur-

Digestion: current stakes

pose solution that achieves a 30% reduction in sludge

Europe has undertaken to drastically reduce its green-

mass compared to conventional dewatering. For the

house gas emissions setting a target of producing 20%

ultimate reduction of sludge volume, Degrémont has

of its total energy from renewable sources by 2020.

improved the dryer technology and developed two spe-

Sludge digestion, which was previously considered as

cific processes: Evaporis LT (low temperature dryer) and

a just a sludge treatment technology, is currently per-

Evaporis LE (low energy dryer) to reach a 90% dryness

ceived as an alternative to fossil-based energy sources.

residue and reduce the energy comsumption.

JANUARY/FEBRUARY 2014

27

INDUSTRY NEWS

RURAL COMMUNITIES

Davey signs distribution agreement with SafeQuip South Africa, home to over 51 million people, has seen its fair share of natural disasters. Now another one looms: water shortages can become a reality very soon, writes Malcolm Corns of SafeQuip.

S MORE AND MORE PEOPLE migrate into

What Davey looks for is a partnership that will help

cities from rural villages, the pressure for the

build the brand in such a way that market expectations

city to meet water demands is ever increas-

are met in a sustainable and profitable manner. The

ing. Although South Africa can boast one of

correct partnerships are essential as the manufacturer,

the cleanest water systems in the world, a lack of san-

distributor and client all have to benefit from the rela-

itation and access to adequate water

tionship in order for it to be a success.

A

supply in the rural communities increases the threat of water-

SafeQuip

Brand

Manager

for

Davey

Malcolm

Corns

was

borne disease ‒ a threat that

appointed to develop brand

can potentially affect millions

awareness in South Africa and

of people each day.

to solidify the companies work-

It is for this reason that

ing relationship.

Traditionally,

Australian water treatment,

the Davey Firefighter has been

transfer, conservation and

known as South Africa s lead-

filtration Water has a

specialist

Davey

ing firefighting engine-driven

(Davey)

pump and over the years

established

has become a product with

agreement

a single focus, states Corns.

Products recently

distribution

into the country with local firefighting

Davey s range offers various

equipment

approaches to influence and

wholesaler, distributor and

change the way in which wa-

manufacturer SafeQuip.

Considered

the

ter is transferred, consumed

leading

and used. In other words, the

manufacturer and wholesale

way in which water is con-

distributor

served and used efficiently.

and

of

firefighting

water-related

ment

in

Southern

SafeQuip

has

innovative various

equip-

This requires introducing

Africa,

new, dependable, and inno-

pioneered

solutions

industries

for

vative water solutions when

in

and where people need them,

over

supported by the best service

three decades.

and advice.

With an extensive range of SABS-approved products, SafeQuip delivers a one-stop-shop solution for products for the transfer, conservation, treatment and filtration of water, servicing some of the toughest environmental and climatic conditions on the continent.

Davey s International Business Development manager, Gary Dryden, says: The Australian and South African

The implementation of the agree-

The Aquashield range of equipment

ment is now taking place with business structures being developed to expand the product ranges offered and at the same time building up the level of stock and dedicated support materials. Eight SafeQuip employees have already visited the Davey factory in Australia for product training.

market conditions have many similarities. It has been

28

a strategic focus for the company to grow its footprint

Product range

in this country by entering into a strategic partnership

Dryden says Davey s expectations for the success of

with a distributor that is well-positioned and already

its product range in South Africa are high. There are

operates within key market channels.

enough similarities in the market to suggest that if we

He adds that the SafeQuip management team are

get it right in terms of product quality ‒ supported

prepared to invest in creating product awareness, ware-

by the excellent service offered by SafeQuip with

housing of stock and spare parts, developing product

us supporting their efforts ‒ we will be successful in

support and training for customers as well as staff.

this market.

JANUARY/FEBRUARY 2014

INDUSTRY NEWS

Every year millions of children die from drinking polluted water.

Davey have water disinfection covered.

Our goal at this stage is to get the product support structure cor-

Davey’s AcquaShield water treatment solution

rect. After that, work on getting the other business functions in place will continue.

The product range includes household pressure and booster systems, firefighter pumps, floodfighter pumps, pressure tanks, shallow and deep well jet pumps, sump pumps, water treatment units, rainwater harvesting and purification equipment, as well as pond pumps, submersible borehole pumps and vertical multistage pumps.

Pressure boosters and Torrium 2 The pressure boosting systems are used to increase the pressure of a stored water source being supplied through a pipe and pump system. These products are useful to boost water pressure to households, commercial properties and rural areas such as temporary settlements.

The combination of the high pressures supplied by these systems and constant flow control provided by the Torrium enables consumers to enjoy the benefits of a strong comfortable shower from a pump that does not cycle plus the reliability of adaptive technology.

The pressure boosting products include the Davey HP, Davey HS, Davey HM, Davey XP, Davey XJ and Davey CT, all of which feature the Davey Torrium 2 smart controller. The controller is

Experts in water.

designed to supply pressure-boosted water at a constant flow and also incorporates high-level pump protection.

Other features of the Torrium 2 include: • A quick cut-in for even water pressure: It senses water demand quickly ensuring there is no lag in the supply, cutting in when the pressure has dropped to 80% of the previous top (shut-off ) pressure.

• Great hydraulic performance and dry run protection: It is

Many homes in and around South Africa use water collected from unsecure sources such as rainwater harvesting, rivers and boreholes. All surface water can harbour micro-organisms that are potentially dangerous to your health.

Davey Water Products offer a range of products designed to make drinking water safer. From manual dosing with liquid to point of entry filtration, UV, and water softening systems. It is easy to treat all incoming water into the home to ensure water clarity and safety at every tap.

designed with large pathways and has no moving parts. The design reduces energy waste and ensures the pumps performance is unaffected at high flow rates. Dry run protection prevents damage when the pump runs dry by stopping the pump.

• Auto-retry and adaptive starting: Auto-retry enables the pump to reset itself after a loss of water, reducing system

Email us on davey@safequip.co.za to find out more about the full Davey range or contact any of the SafeQuip branches to find your nearest dealer.

Gauteng: Western Cape: Kwazulu-Natal: Eastern Cape:

011 021 031 041

397 907 579 451

7723 2500 4674 0026

Davey is exclusively distributed by SafeQuip.

JANUARY/FEBRUARY 2014

29

QUALITY FIRE SOLUTIONS

INDUSTRY NEWS

Manage the entire urban water lifecycle

The world’s most comprehensive software solution for urban water infrastructure.

Bentley’s fully-integrated water and wastewater software solution addresses the needs of owner-operators and engineers who manage the urban water infrastructure lifecycle, while saving design, project, and operating costs, and improving safety.

Isn’t it time you learned how Bentley can help improve the performance of your water infrastructure?

For more information, please visit:

www.bentley.com/ZA © 2013 Bentley Systems, Incorporated. Bentley, and the “B” Bentley logo are either registered or unregistered trademarks or service marks of Bentley Systems, Incorporated or one of its direct or indirect wholly-owned subsidiaries. Other brands and product names are trademarks of their respective owners.

3847 Wetpaint Advertising

INDUSTRY NEWS downtime. Adaptive starting adapts to reduce cut-in pressure when a small leak is detected.

Water harvesting An efficient rainwater harvesting system can take advantage of the rainwater that falls on our homes. By harvesting rainwater for toilets and laundry usage, up to 40% of your home s average domestic water usage can be saved.

Davey s RainBank is ideal for metropolitan rainwater harvesting on homes, toilet blocks and garden irrigation. It automat-

Although South Africa can boast one of the cleanest water systems in the world, a lack of sanitation and access to adequate water supply in the rural communities increases the threat of waterborne disease ically switches between rainwater and mains water supply, so there is no need for consumer intervention.

Its unique patented, yet uncomplicated technology, provides a dependable solution to rainwater harvesting, saving valuable water reserves and monthly costs.

Washdown and irrigation pumps Davey also offers washdown and small irrigation water transfer pumps. The washdown pumps are ideal for cleaning agricultural operations or heavy equipment. For washdown applications, the pump provides high pressure while using little water.

The pumps are also great for providing properly pressurised irrigation inside the forestry nursery. The full range includes the Dynaflo 6000, SS series, XF series, CY series and JY series

Manholes that last for more than a lifetime

pumps as well as the Mukmova.

Vertical multistage pumps These versatile pumps can be used individually or together in various applications such as agriculture, turf watering, pressure boosting, high-pressure washing, water treatment, boiler

Future roads will continue to

pressurisation as well as water supply for domestic, rural and

need manhole access to stormwater,

industrial uses.

sewerage and communication pipelines.

The VM series offers a full range of vertical multistage centrifugal pumps with all stainless steel hydraulic parts. The 56

Superb design and leading-edge manufacturing

models provide flow rates from 0.4 m3/hour and pressures up

processes ensure that ROCLA provides truly

to 230 m to suit a full range of domestic, farm and industrial

reliable manhole solutions. ROCLA manholes are

applications. Standards pumps operate at 50 Hz.

maintenance-free and will never require upgrading – if it’s not broken, why fix it? ROCLA manholes

Water treatment

are ready for the future.

Meanwhile, Davey also supplies water treatment and filtration products that can be used to convert stored water into safe drinking water. The filtration products include the

ROCLA is ISO 9001:2008 certified and has the

AcquaShield filtration units and AcquaSafe, a unique product

SABS mark of approval on all applicable products.

formulated to protect stored water from contamination helping to ensure a safe water supply.

SafeQuip s knowledgeable staff are able to provide the best

ROCLA

advice for choosing the correct pumps and water-related products for small to large operations in different industries ranging from agriculture to water conservation.

Corns states: Success in the conservation of water will be

OUR DIFFERENCE IS CONCRETE

determined by the success with which we manage our dayto-day water demands. Water conservation is not a maybe solution, but rather an insurance policy to our survival.

JANUARY/FEBRUARY 2014

31

Contact ROCLA now on Tel: (011) 670-7600 or Fax: 086 675 8985 Web: www.roclaproducts.co.za

INDUSTRY NEWS

WETLAND MANAGEMENT

Award for WRC wetland management tool The Water Research Commission (WRC) received special recognition at the Annual National Wetland Awards, sponsored by Mondi, for funding and publishing the Wet-Management Series.

T

HE AWARDS WERE HELD on 22 October 2013 at the National Wetland Indaba, Cape St Francis. This prestigious event recognised the outstanding contributions and achievements

of those doing wetland work and successfully showcased innovation to the wetland sector and the public.

Bonani Madikizela, a WRC research manager, received

Wetlands are fascinating and dynamic ecosystems Source: Mondi Wetlands Projects

Biodiversity Institute. Other key partners included the Department of Water Affairs, Mondi Wetlands Project, provincial

conservation

Other award recipients included Craig Cowden from GroundTruth, KwaZulu-Natal and Doug Woods, a farmer from Kokstad, KwaZulu-Natal, who were recognised for their Wetland Stewardship and successful wetland rehabilitation projects. Dr Heather Malan from the Freshwater Research Centre, Western Cape, received an award for Wetland Science and Research in recognition of a range of wetland research projects and related scientific publications.

The WET-Management Series is a set of integrated tools specifically developed to help users achieve well-informed and effective wetland management

and

provide

indispensable

ecosystem

services.

Commonly referred to as marshes, swamps, bogs or vleis, they constitute about 2.4%

Wetland loss in South Africa has been significant.

Because wetlands are transitional between aquatic and terrestrial ecosystems, they are vulnerable to impacts on both

of South Africa s surface area , says Madikizela.

They support a range

of specialised plant, insect, bird and mammal life and also supply wild food, grazing, building and craft materials to people. Wetlands play a key role in absorbing flood waters, improving water quality and regulating stream flow, helping to maintain ecosystem functioning downstream.

In

many

parts

of

South

Africa,

wetlands are important sites for small-scale subsistence agriculture.

and rehabilitation. It is the product of the Wetland

Many culturally and economically important species are

Rehabilitation component of the National Wetlands

found in wetlands, including wild food, craft and me-

Research Programme, an initiative of the WRC. This

dicinal plants that are important for rural communities.

component was jointly funded by the WRC and

Wetlands are a source and basis of economic develop-

the

ment and support livelihoods in every aspect; without

former

Department

of

Environmental

Affairs

and Tourism, through the South African National

32

universities

Wetlands are fascinating and dynamic ecosystems that

the award with pride from the Deputy Minister of Water and Environmental Affairs, Rejoice Mabudafhasi.

agencies,

private enterprise.

them there is no water, there is no life.

JANUARY/FEBRUARY 2014

INDUSTRY NEWS According to Madikizela, the challenges of wetland

Dr Stanley Liphadzi, WRC Executive Manager, says:

management and rehabilitation span a range of spatial

Many of South Africa s wetlands are already lost be-

scales and institutional levels, from the national and

cause of agriculture, timber plantations, mining and

provincial to the level of specific wetland sites involv-

urban development. Studies in several major catch-

ing individual landowners. Whereas national policy

ments have revealed that between 35 and 60% of our

and legislation provide clear direction and support for

wetlands, and the benefits they provide, have been lost

rehabilitation, the very complex links between people

or severely degraded. But degradation is not neces-

and wetlands mean that actions aimed at sustainably

sarily permanent, and international and South African

rehabilitating and conserving wetlands will depend on

experience has shown that it is possible to recover

the dedication and commitment of all stakeholders,

some of the health and values of degraded wetlands

especially landowners and wetland users.

through rehabilitation.

When planning rehabilitation, it is therefore necessary

Wetland rehabilitation as a means of addressing past

to consult openly and comprehensively, and to incor-

degradation forms part of an effective wetland con-

porate the contributions of landowners, land users and

servation strategy, as does protection and wise use. In

other key stakeholders such as municipal bodies or pro-

South Africa, wetland conservation is being increasing-

vincial departments who will also beneďŹ t from the reha-

ly addressed through a range of policy and legislative

bilitation. Care must be taken to address both the causes

frameworks, particularly within the environment and

and symptoms of wetland degradation. Clear measurable

water sectors. Furthermore, several multilateral agree-

objectives are required and rehabilitation plans need to

ments which South Africa is party to have incorporated

be developed with a multidisciplinary team that includes

the two-pronged approach to maintaining healthy

expertise in both ecological functioning and the design

wetlands while rehabilitating degraded ones.

of rehabilitation structures.

Why rehabilitate wetlands Wetland loss in South Africa has been significant. Because wetlands are transitional between aquatic and terrestrial (water and land) ecosystems, they are vulnerable to impacts on both. In addition to direct impacts, such as draining for pastures and crops, or the construction of infrastructure such as roads that impede and concentrate water flows, there are also severe ongoing impacts from pollution and erosion in catchments as well as from excessive water abstraction, loss of vegetation cover, climate change and land use change.

JANUARY/FEBRUARY 2014

33

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INDUSTRY NEWS

SEW EURODRIVE

Design challenge winners raise the bar The panel of engineering specialists who gathered together to review entries for the PneuDrive Challenge 2013 Engineering Design Competition, concluded that an elegant design from two students from the Cape Peninsula University of Technology was the best entry.

HIS ANNUAL student engineering competition,

T

initiated in 2008 and sponsored by SEW Eurodrive and Pneumax, takes as one of its starting points the acknowledgement that businesses need to

commit to initiatives that can effectively allow students to demonstrate their academic knowledge on a practical business level. This year, students were asked to explore

PneuDrive Challenge 2013 Winners – CPUT – Gareth Hardman, Christian Mpiana, Francois Hoffman

roads and paths will bring to these areas, they proposed that other possible business interventions around the system could generate job creation. Lecturer Francois Hoffman expressed that his students winning the competition was the highlight of his year.

a Greener Mining theme where they had to review typical problems that mining operations need to control. lems and risks associated with slurry dams, rehabilitating

2nd Place: Tshwane University of Technology ‒ The Dust Buster

mines and how to improve water recycling on mines.

The difference between first and second place was a mere

The problems of extracting and finding a use for mining

3% ‒ the closest margin in the history of the competition.

by-products and controlling dust emissions were also part

However, students Alexander Jansen van Vuuren, Francois

of the problem set.

van Dyk, Myron van Staden and Daniel Posthumus can

Students had to select a specific area such as the prob-

As in previous years, the judging panel was made up of

be proud of the fact that their design won the Innovation

specialists with a wide range of business and engineering

Prize. They submitted a unique design concept that com-

experience. The feedback they provided on the entries

bines the use of low frequency sound waves, extraction

indicates that South Africa s engineering community can

fans and wireless systems to address the problem of

expect to receive a number of energetic and innovative

removing dust in a mining environment. Lecturer Johan

young engineers into their ranks in the near future.

Benade conveyed excitement about the design and felt that it was worthy of attention from potential investors for

1st Place: Cape Peninsula University of Technology ‒ Waste Granite to Cobblestone Machine

further development.

After two intensive days of judging, the panel concluded and agreed that this entry presented the best technical

3rd Place: Wits University ‒ Tailings Dam Water Solar Still

solution for solving a real-life business and environmental

Students Gregory Behrens, Travis Bennett, Paul Hon and

problem. Students Christian Mpiana and Gareth Hardman

Thomas Wyszkowski-Korwin submitted an equally unique

submitted a design that proposes the rehabilitation of

design concept that focused specifically on addressing

abandoned granite mines by turning surplus

water losses in tailings dams. Their automated solar still

waste

design showed how water can be captured on tailings

granite blocks into usable cobblestones. These can then, in turn, be used to develop access roads and walkways in rural areas. In addition to the direct benefit that paved

Judging Panel

dams and then fed back to mining operations for reuse.

This has the advantage of minimising the dependency on fresh water supplies, a challenge that most if not all mines currently face.

A second entry from Wits ‒ a dust emission filtration system ‒ won a prize sponsored by Autodesk for the best use of Autodesk Design Technology. Their submission reflects how well Wits students have taken to the potential of this world-leading 3D design and engineering software.

The winners received a 10-day all-expenses-paid trip to Germany and Italy where they will be hosted by the head offices of the sponsor companies. Furthermore, the winning university receives R100 000 worth of products from SEW Eurodrive and Pneumax, while each participating university is entitled to R40 000 worth of products for completing the competition.

JANUARY/FEBRUARY 2014

35

INDUSTRY NEWS

WATER SUPPLY

Turning the tide on SA’s water management challenges The scarcity and quality of water have emerged as trigger points around this precious life-giving liquid at a major symposium hosted by Unilever. With a proactive outlook to addressing some of the country’s many water management challenges, Unilever brought together leading water experts to interrogate South Africa’s looming water crisis. attended by a host of delegates including Unilever representatives, academics with an interest in water issues, some of the country s leading water players, corporate companies, water boards and members of the media.

Professor Tally Palmer from the Unilever Centre for Environmental Water Quality at Rhodes University elab-

“While SA’s environmental law is progressive, a more permanent solution is required to improve the current state of SA’s water supply” orated on the theme of the symposium: Water conversations ‒ What does People for Water mean in the Vaal , saying: We all live in a water catchment and water issues affect everyone. The livelihoods of most people depend on water in some way. Water matters and you

A

CCORDING TO Unilever s Sustainable Living Plan, water shortages are already affecting

Water quality and scarcity were key topics

many parts of the world. By 2025, 1.8 billion

can participate in our water future. The Unilever water symposium offers a ground-breaking opportunity for a wide range of participants to engage with the water issues of our day.

people will be living in countries or regions

We are asking the question: if government has

with absolute water scarcity and two-thirds of the glob-

pledged to hold water in public trust for the benefit all

al population in water-stressed conditions.

people living South Africa ‒ that is, to provide Water for

Water scarcity and water quality emerged as the focal

People ‒ then how do each of us become People for

points for discussion at the symposium, which was

Water ‒ securing our water future?

Industrial effluents, domestic and commercial sewage, acid mine drainage, agricultural overflows and litter are all contributing factors to the country s deteriorating water supply. Moreover, factors such as climate change and unpredictable rainfall further exacerbate the water situation. It is reported that South Africa has an average

Facilitating a water symposium hosted by Unilever is Tally Palmer, p ‎ rofessor and director at the Unilever Centre for Environmental Water Quality at Rhodes University

36

annual rainfall of 450 mm, compared with a world average of 860 mm.

South Africa faces a large number of water quality problems in rivers and water storage reservoirs. Most of these are the consequences of incomplete or inadequate treatment of wastewater effluents from cities and towns, said Dr Peter Ashton, principal scientist at the Council for Scientific and Industrial Research (CSIR) ‒ Natural Resources and the Environment.

Pollution that emanates from industries and mining activities complicates these issues, especially in the Vaal

JANUARY/FEBRUARY 2014

INDUSTRY NEWS River system. This makes it difficult for local authorities to provide assured supplies of drinking water in both urban and rural areas.

We have seen good improvements in the way that effluent is treated and water is purified in recent years, but many problems still linger on. There is a pressing need for national and local authorities to work together to solve these problems as soon as possible, said Ashton.

As part of the company s Sustainable Living Plan, Unilever has set a bold target to halve the water asso-

Dr Washington Nyabeze, Director at WR Nyabeze and Associates; Justin Apsey, Vice President: Brand Building, Home Care at Unilever and Dr Victor Munnik, Wits. Research Associate

ciated with the consumer use of its products by 2020.

I am proud to be associated with a company that is taking an active stance to inculcate good water management practices both in the product manufacturing process and from a consumer education perspective, said Justin Apsey, vice president: Brand Building, Home Care at Unilever.

We

fully

support

Water

Affairs

Minister

Edna

Molewa s view that a collective effort from government, the business sector and civil society is required to ultimately ensure that every South African benefits from

Justin Apsey, Vice President: Brand Building, Home Care at Unilever during his welcome address at a water symposium hosted by Unilever

equal access to this basic human right.

Meanwhile, if we are to achieve a water-efficient economy and a culture of sustainability together, we need to entrench a social ethic of water conservation in the minds of people each and every day. While South Africa s environmental law is progressive, a more permanent solution is required to improve the current state of South Africa s water supply.

Water scarcity is a growing concern amid a rising population and current economic development rates in water-stressed South Africa.

According to a South African National State of the Environment Report, at the projected population growth and economic development rates, it is unlikely that the projected demand on water resources in South Africa will be sustainable.

The Department of Water Affairs deputy regional director for Integrated Water Resources Management (IWRM) and Catchment Strategies, Petrus Venter, said at the event: The environmental footprint of humans has dramatically increased between 10 and 50 times over the past 100 years.

Dr Marjorie Jobson, National Director, Khulumani Support Group, Grahamstown; Justin Apsey, Vice President: Brand Building, Home Care at Unilever and Tally Palmer, P ‎ rofessor and Director at the Unilever Centre for Environmental Water Quality at Rhodes University

the three pillars of water neutrality, energy efficiency and zero waste to landfill in mind. Unilever applied the three Rs of reduce, reuse and recycle to its water consumption and implemented innovative technologies to minimise water use.

In 2002, global Fast-Moving Consumer Goods giant Unilever South Africa funded the establishment of

To sustain modern civilisation, more that 50 million hectares of vegetation are annually disappearing with diversity plunging to become deserts. With less vegetation, local and regional rain patterns change and less water becomes available. More nutrients also wash to the river and dams as development, field fires and erosion increase.

Vegetation and restoration of land and water courses reintroduce natural nutrient filters and increase diversity with more water available from an increase in precipitation.

The three priority targets for Unilever are: reduce water use in the laundry process, promote easy rinse

the Unilever Centre for Environmental Water

Water scarcity is a growing concern amid a rising population and current economic development rates in waterstressed South Africa

products and products that use less water, and reduce water use in skin cleansing and hair washing.

Unilever s Indonsa plant in Durban is the first green manufacturing plant in South Africa and was built with

Quality within the Institute for Water Research at

Rhodes

University

in

Grahamstown,

South Africa.

The objective of the centre is to contribute to the understanding and sustainable management of water resources in Southern Africa. This is pursued through partnerships with industry, local and national government, water resource management forums, communities and other academic institutions. By 2015 Unilever intends to reach 200 million consumers with products and tools that will help them to use less water while washing and showering.

The company s goal is to reach 400 million consumers by 2020. Although progress remains slow, Unilever is continually improving its understanding of this area.

JANUARY/FEBRUARY 2014

37

TCTA is a state-owned liability management entity responsible for bulk raw water infrastructure development

T

he Trans Caledon Tunnel Authority (TCTA) is proud to contribute towards a system aimed at delivering water to the citizens of South Africa. And as the country celebrates 20 years of democracy, the TCTA continues to work together with the South African government to provide sustainable water infrastructure to propel the country’s economy.

As part of the country’s milestones in the part 20 years, the TCTA recently opened the Spring Grove Dam. The construction of this KwaZulu Natal dam is one of nine TCTA’s projects that aim at ensuring water supply to the KZN region. The dam commenced in 2011 during a sod turning ceremony by the Minister of Water Affairs, Mrs Edna Molewa. On 19 November 2013, the President of South Africa, Mr Jacob Zuma, accompanied by Acting

Mooi-Mgeni Transfer Scheme Phase 2 (MMTS2), Komati Water Scheme Augmentation Project (KWSAP), Olifants River Water Resource Development Project Phase 2 (ORWRDP2) , Mokolo-Crocodile Water Augmentation Project (MCWAP), Metsi Bophelo Borehole Project and the Acid Mine Drainage.

Since 1986, we have played a pivotal role in bringing water to the economic nerve-centre of our country. The from the dams in the mountains of Lesotho, through tunnels to South Africa, giving birth to new enterprises and meeting the critical needs of households and communities.

opened the Spring Grove Dam. Other TCTA projects include: Lesotho Highlands Water Project (LHWP) – South African portion of the Delivery Tunnel North, Berg Water Project (BWP), Vaal River Eastern Subsystem Augmentation Project (VRESAP),

For more information on TCTA visit: www.tcta.co.za or Call +27 12 683 1200

DAMS AND RESER VOIRS

SPRING GROVE DAM

The Mooi-Mgeni Transfer Scheme’s second phase completed The Mgeni Water System in KwaZuluNatal supplies water to approximately five million people, as well as to the industrial sectors in the Durban and Pietermaritzburg regions, the economic hubs of the province.

In

November

2007,

the

Trans-Caledon

Tunnel

Authority (TCTA) received a directive from the Minister of Water Affairs to fund and implement the MMTS-2 through the private sector. TCTA is a statutory body originally established under the National Water Act to finance and construct the South African part of the Lesotho Highlands Water Project.

On 15 June 2009, the Department of Environmental Affairs issued a positive Record of Decision for the project and the following components were approved: • the construction of the Spring Grove Dam, and two measuring weirs (one in the Mooi River and another in the Mpofana River) • the construction of a pumping station and transfer pipeline (including a break pressure tank and the outfall works) from Spring Grove Dam all the way to the Mpofana River • an artificial fish barrier on the Mooi River, upstream of the Inchbrakie Falls on the farm Coldstream.

Two appeals were received against the Record of Decision. The Mooi River Farmers

Association

appealed against the dam as they felt that other strategic water resource options were not considered.

They subsequently withdrew their appeal. The Mziki Homeowners Association raised objections about the EIA process, the lack of alternatives for the routing of the pipeline and the lack of proper assessment of the significant impacts.

The appeal against the pipeline was upheld by the Minister of Justice and Constitutional Development on 28 September 2010. A new EIA process was undertaken for the Water Transfer System to determine the pre-

T

HE GROWTH IN WATER DEMAND and intermittent drought periods since 2003 have made it necessary for the Department of Water Affairs (DWA) to implement Phase 2 of the

Mooi-Mgeni Transfer Scheme (MMTS-2).

Spring Grove Dam during construction phase

ferred pipeline route.

The Spring Grove Dam will provide much-needed water to the municipalities via the transfer of water to Midmar Dam. The MMTS-1 was initially used to transfer water to the Mgeni catchment until the new pipeline became operational.

Phase 1 of the MMTS (MMTS-1) consists of the Mearns

On 19 November 2013, President Jacob Zuma of-

Weir situated at the confluence of the Mooi and Little

ficially launched the Spring Grove Dam as part of the

Mooi rivers, downstream of the Spring Grove Dam. From there water is pumped through a pipeline to the outfall at the Mpofana River, from where the water flows to Midmar Dam on the Mgeni River. This scheme was completed in 2003.

After the decision was made to implement MMTS-2, environmental, social and economic studies were undertaken and supported by subsequent Environmental Impact

Assessment

(EIA)

processes,

which

roll out of government s

The Spring Grove Dam will provide much-needed water to the municipalities via the transfer of water to Midmar Dam

Infrastructure

Build

Programme. In his closing remarks in the speech he delivered to the community in Mooi River, he stated: Even as we continue to raise the numbers of those

went

accessing potable water, we need to remember that

through a number of phases. The EIA started in 1999

every drop counts. We must therefore save water. Not a

and was concluded in January 2009 with the submis-

drop must be wasted, not a drop must be polluted and

sion of the final Environmental Impact Report (EIR) to

all infrastructure must be cared for. Water is Life. Let s

the national and provincial environmental authorities.

conserve it, respect it and enjoy it!

JANUARY/FEBRUARY 2014

39

Bringing water to Africa and the rest of the world for

ELEVATED TANKS: ABECO offers full-service design, manufacture and installation of support towers steelwork. Basic towers consisting of the support steelwork with a caged access ladder to the roof of the tank are offered in the absence of further specification.

Walkways around the base of the tank or rest platforms on access ladders are available on request.

Access is required all around pressed steel tanks to tighten bolts. The recommended minimum space around the four sides and above the roof is 600mm and 450mm beneath the tank

CIRCULAR SECTIONAL STEEL TANKS: In developing sectional steel tanks, ABECO recognised a need for tanks that have the following features: • Low cost hygienic water storage • Rugged and easily transportable • Minimal site preparation and foundations • Quick and easy to install • Can be installed using basic equipment • Durable and long lasting • Can be dismantled and re-erected at new sites.

GROUND LEVEL TANKS: Ground level tanks are commonly supported on reinforced concrete dwarf walls fitted with steel capping strips. The purpose of the capping strip is to spread the load over the full load of the support wall and to provide a level platform on which to erect the tank. For practical reasons concrete cannot be cast with sufficient accuracy of level. The capping strips should be positioned in place before the installation of the tank starts.

Recommended tolerance is ±2mm. Care should be taken to ensure that foundation walls are parallel and square to each other. Foundation walls must protrude beyond the edge of the tank by a recommended distance of 150mm. The tapered top section of the wall assists in providing access for the tools to fasten.

6A Bradford Road Bedfordview 2007 South Africa

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DAMS AND RESER FEATURE VOIRS

NDWEDWE

Bulk water supply investigation under way A planning study for the investigation and assessment of a bulk water supply scheme for the southern Ndwedwe area has been awarded.

energy costs that will be unsustainable in the long term.

The study will seek a balance by locating suitable water sources for the supply of each area so that pumping of water is kept to a minimum.

Following the acceptance by the client of the pre-feasibility recommendations, the second phase detailed study will confirm its findings and elaborate on the base information in terms of suitability, feasibility and

I

N A COMPETITIVE TENDER PROCESS involving

cost structure.

eight bidders, international consulting firm Royal

This study is comprehensive and will need to take

HaskoningDHV has secured an 18-month long

into consideration a wide range of institutional, social,

planning study for the investigation and assess-

technical,

financial,

ment of a bulk water supply scheme for the southern Ndwedwe area in KwaZulu-Natal.

The study area involves communities within the iLembe District and was commissioned by Umgeni Water. A reconnaissance study was conducted in 2007 by iLembe and Umgeni Water to assess the viability of a more reliable water resource to this area, which is home to more than 140 000 people.

A number of water supply options were listed, which will now be investigated at feasibility level to determine

economic

and

environmental

issues, all relevant cadastral and land

"Dominant factors in all our engineering work are to combine technical solutions that are sustainable, costeective and are kind to the environment"

water supply options for the area.

ownership details, technical and environmental issues, regulations and constraints that are likely to impact on the implementation of the preferred solution. We are required to define, evaluate and cost all mitigation measures required to address these impacts.

Dominant factors in all our engineering work are to combine technical solutions that are sustainable, cost-

Regarding the details of the study, Ian Rushton, study

effective and are kind to the environment. In this study

leader of Royal HaskoningDHV, says: The study will be

we are seeking to vastly increase energy efficiencies

conducted in two stages: pre-feasibility and a detailed

through a reduction of pumping costs in rugged terrain,

feasibility leading from the accepted recommendations of the former. Work has already commenced with regards the identified options in light of the external environment as it stands today.

It is our task to identify all the potential project pa-

The study involves communities with the ILembe disctrict

to maximise job creation in an impoverished rural area and, by providing bulk potable water supply, stimulate social and economic development while promoting skills transfer through the interaction with stakeholders, Rushton concludes.

rameters, including a 30-year water demand assessment for the study area, as well as identify potential routes and sites for a dam/weir, water treatment works, pump stations, reservoirs and pipelines, and environmental and geotechnical issues, culminating in a recommendation of the most feasible scheme to supply the area with potable water.

He adds: The area is mountainous with difficult accessibility and spread over numerous catchments, which means that different water supply solutions may need to be found

for

different

catchments.

On the one hand, a single large bulk water supply of treated water would simplify operations. On the other hand, this would involve pumping water up over several watersheds, with associated high

JANUARY/FEBRUARY 2014

41

Pressed Steel Sectional Water Tanks

Pressed Steel Sectional Water Tanks

sustainable and long term Water Storage Solutions

Specialists in the manufacturing of domestic and industrial water storage Prestank tank capacities range from 1 500 litres to 4.2 million litres designed to SANS 10329:2004 guidelines and SANS structural codes.

Our Hot Dipped Galvanising units are easily transported and assembled on even the most remote sites.

Structa Technology’s Prestanks are hygienically safe, cost effective and a reliable way to store water for commercial sectors, private sectors and even for personalized storage. Choose from temporary or permanent erection at mines, powerstations, building sites, hospitals, water affairs,municipalities, rural communities and agriculture.

There is a wealth of water storage applications, for which Prestanks are an answer.

STRUCTA TECHNOLOGY is part of the STRUCTA GROUP of Companies

Structa Technology (Pty)Ltd P.O Box 2538, Vereeniging, 1930 Tel: (016) 362 9100 e-mail: Sales and Marketing: tanks@structa.co.za Estimator: watertanks@structa.co.za Director: rodney@structa.co.za

www.structa.co.za Structa Technology is a Level 3 BBBEE Contributor.

DAMS AND RESER VOIRS

STRUCTA TECHNOLOGY

Mammoth tank for Medupi manufactured Gauteng-based structural steel product manufacturer Structa Technology has successfully undertaken, delivered and commissioned a 4.2 Mℓ fire water tank project for state-owned power utility Eskom’s coal-fired Medupi power station.

This is the largest tank manufactured in South Africa to date.

S

TRUCTA TECHNOLOGY S managing director,

contribute to water storage solutions in South Africa

Hercules Rossouw, says the company is always

and Africa.

extremely pleased to assist Eskom and the

The scope of the company s work included the

water industry with products and services that

design, manufacturing, material selection, corrosion protection, supply, delivery and erection of the tank.

The tank, known as Prestank, is divided into two compartments of more than 2 Mℓ each and consists of 1 092 tank plates, with 35 000 M16 fasteners.

Eskom and engineering company Lesedi Nuclear Services tested the tank in July 2012 for faulty pipe connections and leaks once each tank compartment had been filled. The tank was handed over on completion on time.

The tank panels were fabricated at the Structa Technology factory in Meyerton, Gauteng, using a 1 300 t press and automated punching facilities.

Structa Technology director Rodney Cory, Structa Technology MD Hercules Rossouw and production manager Bertus Booysen in front of the 1 300 t press machine at the company’s facility in Meyerton

MORE ABOUT STRUCTA TECHNOLOGY AND PRESTANK: STRUCTA TECHNOLOGY, a member of the Structa Group of Companies, is based in Meyerton, Gauteng, and manufactures electrical masts, utility poles, lighting masts and pressed steel water storage tanks better known as Prestanks.

The company manufactures and supplies the pressed steel water tanks under the 40-year-old brand Prestank. Prestanks are hygienically safe, cost effective and a reliable way to store water for industrial or potable water storage. The Prestank may be used for various water storage applications from temporary or permanent installations at mines, power stations, building sites, hospitals, water affairs, municipalities, rural communities and agriculture. The tanks are fully customisable, high-quality water storage solutions that are manufactured according to SANS guidelines and meet South African Hot Dipped Galvanising requirements.

There are many benefits of choosing a Prestank: • It facilitates construction of an infinite range of sizes and

•

•

• •

configurations to meet the specifications and needs of the client; handrails, walkways and lightning protection are just a few examples of the features available.

The profile panel sections provide excellent strength properties and are structurally sound for storing water. The stand is designed strictly in accordance with SANS 10160 and SANS 10162 for Structural Steel Work. Tanks mounted on steel towers above ground level have an aesthetically pleasing appearance.

Another major advantage of the sectional tank design is that it makes logistics easier. Handling and transportation over long distances and to remote areas, regardless of the final dimensions of the assembled unit, is easily attainable.

Assembly on-site is quickly achieved without the need for sophisticated tooling methods.

Minimum maintenance is required because the galvanised steel panels resist weathering from the elements, while maintaining the integrity

The 4.2 Mℓ Prestank at Medupi Power Station of the water within from contamination of most forms.

• Access to the water tank can be restricted by means of a lockable, ventilated access cover, providing safety and peace of mind to clients.

Reservoirs constructed from pressed steel sections are used extensively by the mining industry and municipal authorities. Large storage tanks of this design, which are mounted on steel towers, can also be seen at many of Eskom’s power stations. Structa’s

JANUARY/FEBRUARY 2014

pressed steel sectional tanks are hot dip galvanised for corrosion control in accordance with the requirements of the SANS 121 (ISO 1461) galvanising standard.

The purpose is to ensure extended maintenance-free life in situations where water with aggressively corrosive properties is required to be stored.

The Structa Group of companies consist of nine subsidiaries active in the manufacturing and supply of structural steel products for water, infrastructure (electrification and telecommunications), mining, petrochemical and industrial sectors.

43

DAMS AND RESER VOIRS

PUMPS

South African contractor to the rescue After a foreign company abandoned a major engineering contract associated with water supply to the city of Blantyre in Malawi, the contracts division of APE Pumps stepped in to save the day.

N SEPTEMBER, the Blantyre Water Board awarded a €4.1 mil-

I

lion (R55 million) rectifying contract to Wadeville-based APE Pumps, covering the completion of the upgrade of the Walker s Ferry raw water and high-lift pumping stations.

each

Walker s Ferry is located some 40 km north-west of Blantyre on the

transfer

water

at

Part of the pumping station at Chileka

750 m3/h at 550 m head

Shire River. The raw water pumping station transfers water from the

across 26 km through two pipelines to Chileka, where our original

Shire River through the water treatment plant using three pipelines,

contract will pick it up and take it to the city.

to the high-lift station which pumps it 26 km to Chileka, where a further pumping station boosts the water flow all the way to storage tanks in Blantyre.

Chileka is itself a separate R100 million contract that APE Pumps is already managing. Awarded to the company in April, work on this part of Blantyre s water supply comprises the manufacture, installation and commissioning of eight multi-stage pumps with electric motors, all motor controls and associated valves, and civil work, which includes demolishing and rebuilding all concrete plinths and bases in the pump house.

To complete the work at Walker s Ferry, APE Pumps will make use of contract components already delivered to site by the defaulting contractor, combining them with key equipment to be manufactured by APE Pumps itself.

Work has already begun, and APE is busy establishing an on-site workshop with fabrication facilities to support it.

The company will repair or replace non-functional valves and associated actuators, fittings, couplings and pipes, together with all pump sets and related electrical equipment, instrumentation, suction and delivery pipe work and fittings.

New high-voltage devices, including the power feeder, transformer, main distribution boards and all cable connection and control cabinets, will also be installed. These are likely to be manufactured by parent company WPIL in India.

By the time the project is completed around mid-2014, all aspects of the existing water intake works and high-lift pumping station at Walker s Ferry will have been rehabilitated, renewed and commissioned, ensuring a continued supply of water to Chileka.

Approximately four-fifths of the components that APE Pumps will need are already on site, delivered by the failed contractor. However, APE has still to manufacture and deliver raw water motor controls and various high-lift pump station valves and actuators, along with all pipework and manifolds.

APE Pumps managing director Peter Robinson says: The recommissioned pumps at Walker s Ferry high-lift pumping station will

JANUARY/FEBRUARY 2014

45

There is considerable satisfaction in knowing that APE Pumps is now managing all aspects of work at both pump stations.

LEARN FROM THE EXPERTS

TRENCHLESS TRAINING COURSE MARCH 11-13, 2014

Equipment Suppliers (Pty) Ltd. Southern Africa

VERMEER.COM | +27 (011) 608-0893

EXPERT TRAINING STARTS HERE. Vermeer Equipment Suppliers will be conducting a three-day horizontal directional drilling course March 11-13, 2014 in Johannesburg. Topics to be covered include HDD principles, technology capabilities, installation and downhole forces, fluid management and tooling selection.

Practical field demonstrations will be an integral part of this course. Drill operators and owners, consulting and municipal engineers are strongly encouraged to attend. Factory representatives from Vermeer, DCI and Baroid will be in attendance. For more information or to register, please call +27 (011) 608-0893.

Vermeer, the Vermeer logo and Equipped to Do More. are trademarks of Vermeer Manufacturing Company in the U.S. and/or other countries. © 2013 Vermeer Corporation and Vermeer Equipment Suppliers. All Rights Reserved.

TRENCHLESS

6$9( 7,0(

Trenchless solutions go a step further

5('8&( &2676 (/,0,1$7( 7+( 5,6.

2) 75(1&+ ',**,1* '$0$*(

Vacuum extracting unit

Trenchless technology specialist Rescue Rod offers a wide range of products for the industry.

Maryke Foulds finds out what is on offer.

A

Horizontal drilling is a practice of trenchless technology that involves drilling an underground hole, while seamlessly feeding in the necessary drill rods, without ÀUVW KDYLQJ WR GLJ D WUHQFK RU GLWFK DERYH LW

CCORDING TO MANAGING DIRECTOR Bobby Smit, underground construction avoids surface disruptions and provides solutions to overcome environmentally sensitive or challenging terrain conditions

where surface construction or open cut may not be viable or

Our cutting edge directional drilling equipment leaves the ground surface and other infrastructure completely XQGLVWXUEHG WKURXJKRXW D GULOOLQJ SURMHFW 7KH GULOO KHDG LV UHPRWHO\ FRQWUROOHG DQG FDQ DFFXUDWHO\ ERUH KROHV for hundreds of metres in varying diameters to install JUDYLW\ OLQHV SUHVVXUH OLQHV DQG FDEOH VOHHYHV

cost-effective.

Possibly the most well-known trenchless technique for new construction is horizontal directional drilling, which is used to install all types of underground infrastructure. Rescue Rod has years of experience designing and managing horizontal directional drilling projects, says Smit.

Horizontal

A key focus area is the utility and construction industry where safe excavation is done via vacuum

directional

drilling

uses a drill bit and a positive displacement mud motor, which is controlled mechanically and hydraulically

from

a

drill

rig

to drill or bore through soils and rock. Drill fluid is pumped through

drill

pipes

from

the

surface to the mud motor where

Contact us for more information or for a FREE Quotation.

Tel: 010 040 3219 ZZZ UHVFXHURG FR ]D ‡ LQIR#UHVFXHURG FR ]D

JANUARY/FEBRUARY 2014

47

TRENCHLESS flow after it has exited the mud motor and drill bit.

Other services include dealing with pipe bursts or cracking. Smit continues:

During pipe bursting or

cracking, and especially in earthenware pipelines with a large joint displacement, a bursting head is attached to a new pipe, which is then winched or thrusted through an existing pipeline while a hammer produces a pulse that cracks the existing pipe, allowing replacement.

Internal pipeline inspections are another area of specialisation for Rescue Rod. CCTV cameras can inspect and record the status of sewer and stormwater pipelines, usually prior to and after the installation of the trenchless pipeline or rehabilitation.

A key focus area is the utility and construction industry where safe excavation is done via vacuum. Smit explains: Vacuum excavations create airflow and depression vacuum in which previously loosened materials are transported through a hose and deposited into the motor converts hydraulic energy

a spoil collection tank. These materials can be broken

into rotary energy and spins the drill bit. The location of the bit is measured with sensors and the data is transmitted through the surface via a hardwired electrical connection or an electromagnetic signal (or combination of the two). The cuttings are transported in the open borehole from the bit to the surface in the drill fluid

48

up safety prior to removal with either high-pressure air

ABOVE HDD drill mud mixer INSET A stretch of damaged pipeline in Kathlehong

or water, or with traditional hand digging tools. There are several benefits to using these systems within utility companies: large reductions in excavation sizes (up to 50%), reduced costs for infill/backfill, less traffic management and improved H&S with the reduction in cable strikes on buried utilities.

JANUARY/FEBRUARY 2014

The rugged range of Ditch Witch Horizontal Directional Drilling (HDD) equipment and Chain Trenchers gives you the punch you need to drill or dig through some of the toughest landscapes. And with a wide choice of attachments, Ditch Witch lets you triumph over those tough jobs – everytime!

HammerHead® pneumatic piercing tools create a compact hole for almost any underground installation with minimal disruption to landscapes, buildings or normal traffic flow.

The latest “must have” tool for municipalities, electrical, cable/ telecom, sewer, irrigation and plumbing contractors.

HammerHead® Tough and Trusted

For further information on hiring a Ditch Witch please contact ELB Equipment.

ELB HEAD OFFICE: 14 Atlas Road Anderbolt Boksburg (011) 306-0700 • e-mail: Elb@elbquip.co.za • www.elbequipment.com DEALERS & BRANCHES - RSA AND EAST AFRICA: BLOEMFONTEIN: (051) 432-3594 • BRITS: (012) 250-1565 • CAPE TOWN: (021) 933-2383 • DURBAN: (031) 464-6522 EAST LONDON: (043) 748-1469 • GEORGE: (044) 878-0874 • KIMBERLEY: (053) 841-0040 • MIDDELBURG: (013) 246-2312 • NELSPRUIT: (013) 755-1003 NAIROBI: (00254) 20 807 0728 • POLOKWANE (015) 293-1978 • PORT ELIZABETH: (041) 451-0232 • WOLMARANSSTAD: (018) 596-3032 DEALERS - SOUTHERN AFRICA: BOTSWANA: (00267) 240-4320 • LESOTHO: (00266) 2831 3926 • NAMIBIA: (00264) 61-234-052 • SWAZILAND: (00268) 518-5348 ZAMBIA: (00260) 212-210-642 • ZIMBABWE: (00263) 4 485 771/2/3/4 For further information on hiring a Ditch Witch please contact ELB Equipment.

TRENCHLESS

TT INNOVATIONS

Focusing on service delivery This year is a significant year for South Africa and its citizens. It marks four years since the Soccer World Cup was held on local soil and, more importantly, it also ushers in the general elections.

A

S IN THE PAST, each general election has a

Also, in the Somerset West area, a 400 mm diameter

pervading theme throughout: the birth of

effluent main was installed where a large section of

new democracy, economic growth, job crea-

this pipeline traversed a green area which was listed

tion etc. This time around, service delivery is

at the forefront The City of Cape Town, with R19.5 billion worth of assets, which includes approximately 10 438 km of water and 9 021 km of sewer networks, has also sought to address these issues (Water Services Development Plan for the City of Cape Town 2011/12 ‒ 2015/16 Final Report March 2011). The city has implemented a number of innovative projects that showcase the potential

as environmentally sensitive by

The trenchless construction sector is specifically geared towards swift and efficient pipeline replacement, installation and rehabilitation

the appointed environmentalists.

A specialist trenchless contractor

was

appointed

to

install

the 160 m section of 400 mm diameter pipeline by means of horizontal

directional

drilling.

The installation was successfully completed by Jaco van Zyl, site

benefits of municipalities working in conjunction with

manager for the drilling contrac-

the private sector where they are able to implement

tor TT Innovations. He also commented on the recent

innovative construction solutions while providing ser-

turnaround seen by employers and stakeholders who

vice delivery, preserving the natural environment and

appear to be putting the environment first by stating

promoting sustainable growth.

that it s a case of progress versus preservation where

One such project was the upgrade of the existing sew-

growth should not be at the expense of our natural

er pump station near Dunoon. This project required the

heritage ‒ especially if alternative construction meth-

installation of two 600 mm diameter pipelines across a

ods such as trenchless technology exists .

heavily trafficked dual-carriage roadway.

Sustainable growth is enabled through effective

A specialist trenchless subcontractor was elected to

asset management. Here, the City of Cape Town is

install two 1 064 mm diameter steel pipelines to house

FIGURE 1:

making significant strides in upgrading its underground

the 600 mm diameter ductile iron pipelines. Both 56 m

BELOW LEFT View of rammer attached to the steel pipe

assets. Large portions of the water and sewer pipeline

long steel pipelines were installed by means of pipe ramming. The use of this innovative construction technique not only saved local road users from the massive disruption and inconvenience that would have resulted from using open-cut excavation, it also safeguarded the existing road infrastructure from premature deterioration often caused by excavation through the road surface.

BELOW RIGHT The 600 mm diameter ductile iron pipes installed within the steel pipe

networks are being replaced by means of pipe bursting. In brief, this trenchless pipe replacement method uses pneumatic or hydraulic energy to displace and fragment ( burst ) the existing pipeline while simultaneously installing a new HDPE pipeline along the same alignment and grade as the existing route. This form of pipe replacement is highly effective in high-density residential areas where the existing water and sewer infrastructure is at breaking-point due to the design life of the underground assets being exceeded. TT Innovations, one of several contractors appointed by

50

JANUARY/FEBRUARY 2014

TRENCHLESS

the City of Cape Town to undertake pipe replacement by means of pipe bursting, reports that it is able to install up to 300 m of water pipe per day without causing any major disruption to the local residents.

The trenchless construction sector is specifically geared towards swift and efficient pipeline replacement, installation and rehabilitation ‒ all under the guiding principles of preserving the natural environment, reducing disruption and inconvenience, as well as rapid construction. The city has shown intent by utilising this sector for various projects; however, more

FIGURE 2: ABOVE View of the wetland area where 160 m of 400 mm diameter pipe was installed using horizontal directional drilling RIGHT View of the drill rig used for the installation in the wetland area

needs to be done to eradicate the sewer maintenance backlog and stem the flow of water losses if the city wishes to meet its 2015 strategic objectives, namely: to decrease sewer over-flows by 20% and to reduce unaccounted-for water to only 15% (Water Services Development Plan for the City of Cape Town 2010/11 ‒ 2013/14 Executive Summary).

51

JANUARY/FEBRUARY 2014

Trenchless Technology Specialist

Our range of services include: • Pipe Bursting • Horizontal Directional Drilling • Pipe Rehabilitation

• Pipe Ramming • CCTV Inspection • Dewatering

• HDPE Welding • Deep Excavation and Shoring • Underground Service Detection

• Slip Lining

• Industrial Pipe Cleaning

• Close-fit lining: COMPACT PIPE

For more information you can contact us: +27 (0)21 761 3474 F +27 (0)21 797 1151 E info@tt-innovations.co.za www.tt-innovations.co.za

WATER ME TERING

APPS AND MONITORING

Call for intelligent water management solutions Wasting water in a country that’s as dry as South Africa is almost a sin – and a very expensive one at that. But while there’s growing awareness around the need to protect and conserve the country’s water resources, at consumer level, millions of litres are lost every year, as well as millions of rands.

W

HAT S NEEDED IS A NEW and improved do-

Communication is critical, especially in poorer areas. What s

mestic water manage-

also key at this stage

ment and billing model,

is to get buy-in from

according to Larry Symington, CEO of

all consumers and the

MyWater, a specialist manufacturer

only way to do that is

and ICT company.

to have solutions test-

The

present

system

is

letting

ed by those who have

everyone down, he says. It s been

to use them ‒ the con-

in operation since 1947 and is grossly

sumers themselves.

outdated. It s also costly, requires

He

special skills, has not kept pace with

suggests

municipalities

that open

technology developments and is not a

up the billing platform

fair system for an economy as diverse

and encourage entre-

as ours.

Symington says a new model is required to reverse the current trend, where only 10% of consumers accounts are in 30 days, while 80% are 90 days or more in arrears, as recorded in the Local Government Revenue and Expenditure report released by the National Treasury in August 2013.

preneurs to apply their minds

There is growing awareness around the need for water conservation

to the development of workable systems, in line with free market thinking, which allows supply and demand to act as a regulator, rather than government policy.

Symington says it s estimated that between R7 billion and R11 billion worth of water is lost down the drain every year, and that this represents a vast amount of

This situation has a serious impact on the munic-

money that could be made available to entrepreneurs,

ipalities cash flow and hampers service delivery, a

creating employment and enabling them to participate

situation we are constantly reminded of in the press,

in the economy.

he adds. The same report also mentions that suppli-

We need to see systems being developed and test-

ers and creditors stand a 50/50 chance of being paid

ed in conjunction with volunteer consumers and the

on time. This is not a situation that is conducive to

private sector. It s time to open up the platform so that

attracting innovation.

manufacturers

In real terms, 40% more water than is needed is pumped, treated and purified at present. In addition, South Africa is looking to Cuba ‒ a country with its own urban water problems ‒ for engineers and geohydrologists to help it tackle its looming water infrastructure crisis, according to Water Affairs Minister, Edna Molewa.

Many municipalities are trying to tackle these issues on their own, but the lack of specialist technology skills

can

compete

with each other to produce

It’s estimated that between R7 billion and R11 billion worth of water is lost down the drain every year

is placing undue stress on municipal officials who do

solutions based on competitive pricing, service and product reliability ‒ all factors needed to survive in business generally. South Africa is alive with innovators. The municipalities must realise that they will be the biggest beneficiaries of

take an interest, says Symington. Their ability to hold

these advancements, as they

manufacturers accountable is unfortunately hindered

will in time inherit a fully functional and tested system

by supply chain management policies, a system that

accepted by all communities.

also fails many people, as faulty products land up in municipal graveyards, all at ratepayers expense.

The team from MyWater have also developed a water consumption calculator app, which calculates

Symington says that consumer participation is sorely

how much an average household should be spending

needed, as is earlier access to water usage informa-

on water each month. For more information, visit

tion, a modern billing model and communication.

http://waterconsumptioncalc.appspot.com

JANUARY/FEBRUARY 2014

53

SAVING WATER. SAVING LIVES. The only meter that gives the ability to: • Operate as either conventional or prepaid • View your current and previous month water bill • View your remaining free water • View your available credit (Rands) • Purchase credit from your cell phone or convenient stores • Detect your property leaks • Electronically lock your meter

523 Church Street • Provisus Building • 1st Floor • Arcadia • Pretoria t +27 012 440 9885 • f +27 012 440 9751 • email info@lesira.co.za Naphtali Motaung, Executive Sales & Marketing Manager • t 072 736 2995 www.lesira.co.za

WATER ME TERING

PREPAID METERS

Intelligent metering offers tight control Its choice of metering systems for South Africa’s unique demographic is where LesiraTeq comes into its own. Maryke Foulds speaks to Naphtali Motaung of Lesira-Teq to find out what is on offer from this innovative company.

T

HE ABILITY TO CHOOSE which meter is most applicable without having to reprogram or reinstall provides the service provider with tight control over the total system.

Our intelligent water meters offer control over the

total system, including asset management. They can also support systems such as a fixed radio network or a link to other systems. This adaptable computer-based metering technology was developed in South Africa and can operate in different user selectable modes as is supported by a variety of support systems, says Motaung.

A full range of water meters for all South African applications

months by adding the indigent allowance to the system.

After the set number of months, the allowance will fall away. The user will be then have to reapply and should they still qualify, the allowance will be reinstated via the MMS.

The prepay mode has been in operation for a number of

Authorities can set the variables on the MMS. This in-

years and requires the user to purchase credit in advance.

cludes the tariffs, free basic water, emergency water and

Motaung continues:

dates on which it becomes effective.

It offers the service provider a

reduced administrative and financial burden. The service

The post-paid mode allows the user to obtain water

provider receives payment in advance and there are no

on a credit basis up to a set debt limit. Motaung says: In

costs involved in collecting outstanding payments. Bad

this mode the user can freely move between the cheaper

debts are therefore eliminated.

pre-pay mode and the more expensive post-pay mode,

The step tariff used in the system serves to prompt the

without first obtaining permission from the service

user to use water sparingly. With risks and running costs

provider. Each user can set a negative credit. This takes

reduced to a minimum, the service provider can offer

into account his/her credit worthiness and debt allowed

users water at the lowest possible price.

in terms of legislation. When the negative credit limit is

This patented approach, whereby one meter can be

reached, the meter valve will close, preventing an unau-

used in different modes to meet different expectations,

thorised build-up of debt. Under normal circumstances,

is known as the Lesira-Teq Intelligent Meter. With this

there is no requirement for any intervention from the

one meter, different rates can be assigned to cover

service provider, i.e. there is no need for billing. The man-

associated risks and costs as the meters do not have to

agement system electronically monitors the usage and

be removed for reprogramming. Modes are switched by

payments in order to identify any faults or abuse of the

simply changing the setting on the computerised meter

system and notifies the service provider accordingly.

management system (MMS).

Lesira-Teq also supplies conventional meters. Motaung

The prepaid model is available with the following

says: In the conventional mode, the meter operates

variables. The Lifeline valve, which can be retrofitted,

the same as an ordinary meter and a full consumption

means that a client will not be without water when the

and account detail is available to the user via the meter

meter runs out. It works on the principle that when the

at any given time. The user receives an account, which

main valve closes, a valve still permits a measured flow

must be settled within a given time. To compensate for

of about 45 ℓ/hour, which the user must pay for. It thus

the extra administration required and the risk of non-pay-

provides the user with some water essential for personal

ment, the cost per litre is normally more than with the

use during the time the user has to go and purchase ad-

other modes.

ditional water credit. However, should the user abuse the

Lastly, the meter is also available in dispensing mode.

system by not paying, the valve will be manually removed

This is typically used when providing users with a water

from the meter at the expense of the user.

allowance. This can, however, be increased by a set vol-

An Indigent Allowance also allows the standard Free Basic Water allowance to be increased for a set number of

ume against payment. This model is very restrictive and is seen as discriminating.

JANUARY/FEBRUARY 2014

55

WATER ME TERING

TECHNOLOGY

Meter readings can save water The complication of obtaining accurate water meter readings due to restricted access and availability is a recurring problem for developments.

T

HE NEED TO PHYSICALLY ENTER properties

scenarios. Utility man-

to capture water readings for local authorities

agement companies

or utility companies can be onerous ‒ this is

are making use of

where the benefits of smart technology lie.

AMR in this fashion

Basil Bold, managing director of Sensus South Africa,

to combine billing as

says: A common complaint by members of large resi-

well as management

dential or industrial park development is that water bill-

data and often provid-

ings are estimated due to an inability to access either

ing clients/tenants with

the centralised or individual meters. In addition, when

log-ins to web facilitated

the water account suddenly and dramatically increases,

graphic displays of consump-

there are large costs involved as research is undertaken

tions and flow profiling. This al-

to locate a possible leak or burst pipe or incorrect meter

lows for proactive leak detection

reading. Smart technology introduces an element of

and water balance calculation.

proactive maintenance due to its ability to provide near real-time knowledge and measurement. South Africa is facing a water crisis due to unmonitored waste and lack of consumer education. I believe smart meters for utility readings are the most cost effective.

Sensus has enjoyed partnerships with various property developers, utility management companies, in-

Seamless integration into systems Bold continues: Beside the identification of leakage and excessive water consumption, time stamped monitoring in the event of ownership changes allows for accurate cut-offs and reduces the likelihood of disputes.

Smart water meters typically offer an intelligent

dustries, municipalities and private individuals with its

interface

automated meter reading (AMR) applications.

munication

AMR and advanced metering infrastructure data can be split into two parts: billing and management. AMR systems manager, Justin Brown, says: Billing data comprises a unique identification number for the meter as well as a consumption valve read at set periods. Great success has been achieved in typical residential complex environments with the installation of individual

56

Smart technology obviates the need to capture information manually

“Smart technology introduces an element of proactive maintenance due to its ability to provide near real-time knowledge and measurement.” Basil Bold, managing director of Sensus South Africa

to

a

com-

system.

Therefore, the necessary

technical

infra-

structure required for smart

technology

to

operate optimally requires local authorities and

their

delegated

sub-metering ‒ where tenants now pay for the water

utility company to have

they consume and not just a bulk proportioned value

the foresight to implement a changeover

obtained from a single meter. This advantage, coupled

to smart technology and that property

with the accuracy of electronically read data (AMR),

developers embrace it in the develop-

ensures timeous accurate billing and accountability.

ment s planning stages.

Due to the energy crisis we currently face, individual

Worldwide, Sensus is regarded as the

geysers for units within complexes are virtually a thing

smart metering company with major

of the past. Sensus hot water metering/energy meter-

global experience in this field. We provide

ing, coupled with an AMR capability, allows not only for

real world, high-value proven solutions in

the billing of water consumed, but also the ability to bill

the measurement of water, gas, electric

energy utilised.

and heat utilities. It is often said that

Management data is typically read more frequently

to measure is to know , without which

than billing and often focuses on flow profiles over

the current water wastage and billing

time periods, maximums and minimum values as well

confusion will continue to be a burden to

as alarm conditions for possible leakage or burst pipe

property owners, Bold concludes.

JANUARY/FEBRUARY 2014

PROFILE

DESALINATION

Herman Smit of Quality Filtration Systems (QFS)

QUALITY FILTRATION SYSTEMS Fresh water is a finite and vulnerable resource. Population growth, urban sprawl and climate change have resulted in increasing demands for fresh water globally. Herman Smit of Quality Filtration Systems (QFS) gives Maryke Foulds some background on the company as well as the current status of desalination in South Africa.

at a pore size of 0.04 micron.

Reverse osmosis (RO) The RO membrane process removes the dissolved solids and produces water that can be reused. Different RO membranes, at different

ESALINATION of ocean

D

commissioning. Our internal

must be extracted from the

pressures, are implemented,

and brackish water is a

engineering capabilities include

water source. This could be

depending on the amount of

forward-looking solu-

mechanical and electrical

a simple process of diverting

dissolved solids in the water.

tion to global climate change

engineering for integrated

wastewater under pressure or

The cost of desalination is con-

and clean water shortages.

processes, allowing us to

the extremely difficult process

tinually decreasing. Both capital

Pioneering technologies that

provide complete turnkey

of seawater extraction.

costs and operating costs are

are both economically viable

solutions. This means we can

and environmentally sustaina-

customise and design water

Pre-treatment and filtration

technologies and approaches.

ble without jeopardising plant

treatment plants using the

Before the removal of the salts

Energy recovery devices and

being optimised with new

productivity is a key focus area for a number of companies in South Africa. Desalination offers opportunities and profitable growth by reinventing and

low-energy membranes are

Desalination offers opportunities and profitable growth by reinventing and innovating ways of securing an increasingly scarce resource

innovating ways of securing an

some of the developments that are reducing desalination costs.

For the African environment, desalination technologies offer the ability to provide

range of technologies we

(dissolved solids) can be done,

decentralised treatment, with

represent in South Africa. A

the suspended solids must

reduced infrastructure costs.

What is the company s history and involvement with the water industry in South Africa?

wide range of applications ‒

be removed.

This can have an advantage in

QFS was established in 1996

equipment. We have a very

and specialises in providing

strong commissioning team

membrane technology

and only QFS personnel install

solutions to the water industry.

the membrane equipment.

As a technology and equipment

Ancillary equipment like

supplier to the industry, we

tanks, frames and external

stay up to date with the latest

pipework (not critical to the

technology used internationally.

membrane operation) might

We have the capacity to

be subcontracted.

increasingly scarce resource.

from drinking water plants to

Suspended solids, including

acid mine drainage solutions

microorganisms, are mostly

‒ require membrane-based

removed with ultrafiltration

Reverse osmosis equipment installed by QFS in 2012

design, manufacture, install, commission and maintain membrane plants and general water treatment equipment in South Africa.

Our manufacturing plant

Please explain the process of desalination and the costeffectiveness of this on the African continent.

The term desalination describes

is in Cape Town, where we

the process of removal of

manufacture predominantly

dissolved solids in any water

membrane-based water

source ‒ seawater, industrial

treatment equipment.

wastewater, brackish ground

We have coded welders,

water, municipal wastewater,

fitters and engineering staff

etc. The full process

employed to comply to quality

encompasses treatment steps

standards and accreditation.

to achieve the final desalination

Our technology suppliers also

result. These are:

provide engineering support for the technology during

Intake or extraction

design, manufacturing and

The water to be treated

JANUARY/FEBRUARY 2014

57

PROFILE MEMORABLE INSTALLATIONS

Pre-treatment

Pearly Beach – 2.2 Mℓ/day Cape brown water Treatment Plant (2010):

• ultrafiltration

• microfiltration • floatation

• Start-up: August 2010 • Process configuration: Blended water from two dams, pinpoint flock formation with minimal chemical dosing, Memcor ultrafiltration (UF), carbon filters.

• Product water quality: SANS Class I drinking water.

• clarification • precipitation

Final separation • Reverse osmosis • Evaporation and distillation (brine treatment)

Koronga, Malawi – 10 Mℓ/ day lake water treatment plant (2009/10):

What are the main opportunities and challenges in this particular sector?

• Start-up: March 2010 • Process configuration: Water from Lake Victoria screened down to 100 micron and filtered through Memcor UF. • Product water quality: WHO drinking water standards

The pre-treatment portion of the process is critically important to the success of

Steelpoort, Tubatse – 5 Mℓ/ day process water filtration plant (2010):

• Start-up: September 2010 • Process configuration: Waste water from the Samancor facility pre-filter through Memcor (UF membranes as protection for the RO membranes.

• Product water quality: UF permeate NTU < 1

Mossel Bay – 5 Mℓ/day desalination reuse plant (2009/10):

• Start-up: June 2010 • Process configuration: Final effluent from WWTW, Memcor UF membranes as protection for the RO membranes.

• Product water quality: UF permeate NTU < 1.

Beaufort West – 2.3 Mℓ/ day Direct Reclamation Plant (2010):

• Start-up: December 2010 • Process configuration: Memcor UF to remove all TSS, two-staged RO, permeate water treated by ultraviolet light and hydrogen peroxide as an advanced oxidation step.

• Product water quality: SANS Class I drinking water

De Kelders – 1.6 Mℓ/day water treatment plant (2011): • Start-up: December 2011 • Process configuration: Blended water from two borehole sources, iron oxidation by aeration, UF, two-stage brackish water RO, partial blending of RO permeate with UF filtrate.

• Product water quality: SANS Class I drinking water.

Arcelor Mittal – 5 Mℓ/ day wastewater treatment plant (2012):

• Start-up: August 2012 • Process configuration: Water is fed to the plant through a high-rate clarifier, which acts as a high turbidity protection step, two Memcor UF skids and three two-stage RO skids, which are fed from a common manifold.

• Product water quality: Conductivity < 200 μS/cm.

58

the RO membranes. Each application has different water characteristics and requires a unique pre-treatment solution. Understanding these requirements and providing the best quality feed water to the RO membranes will result in

Ultra filtration equipment as pre-treatment to RO installed by QFS in 2012

can they be used further downstream?

more sustainable solutions with lower life cycle costs.

With the separation of the

commonly referred to as the

Can you give an outlook on the water industry in South Africa and how can your products assist with this?

Is there a real need for desalination in South and Southern Africa and what are the real statistics on water shortages?

brine stream. RO systems must

We have seen a move to a

be designed to reduce the

multisource approach to assure

volume of the brine stream.

a sustainable water supply.

The brine stream can be treated

This entails identifying the

further by precipitation or crys-

different water sources from

South Africa is a water-scarce

tallisation of the salts , ending

surface waters (dams and

country and requires a balanced

up with a solid waste that can

rivers), groundwater (boreholes

view when deciding on the

be used for other applications.

and aquifers) and wastewater

use of water sources and the

Understanding the chemistry

to be treated as potable or

treatment processes required.

of the feed water will result in

industrial water.

We cannot be dependent

the correct processing of the

QFS will be instrumental in

on single water sources for a

inorganic minerals for reuse.

the future through the supply

dissolved solids from a salty many areas with limited access

stream it creates a smaller but

to fresh water.

more concentrated stream

sustainable supply of potable

of equipment and sharing of knowledge gained from

Desalination is one of the

Are your products customised to each project?

most energy-intensive water

QFS has a business model that

suppliers. QFS s ability

treatment processes, but it is

starts with a basic design for

to localise world-leading

required for the removal of

the technologies, but allows

technologies for an affordable

dissolved contamination. The

for adaptation for individual

offering will ensure our

popularity and necessity for

applications. This saves a

involvement in the future South

desalination will increase with

tremendous amount of time

African water market.

the increased water shortages

and engineering effort by

The approach taken by QFS

experienced in Southern Africa.

starting with standard pre-

to support the technology and

engineered equipment.

equipment from design phase

and process water.

What are the environmental impacts of desalination?

What happens to the excess salt and minerals, and

As the entire process is

our international technology

through to implementation and

important, QFS provides

commissioning is a business

technology for pre-treatment

model that will benefit the

and final separation processes.

end client.

JANUARY/FEBRUARY 2014

TECHNICAL PAPER

CHP

The installation of CHP at Johannesburg’s Northern WWTW This abridged paper details Johannesburg Water’s challenges and highlights in installing the first South African combined heat and power (CHP) plant at the treatment works, which collects and treats domestic sewage from Alexandra, Sandton, Randburg, the northern areas of Johannesburg, Bedfordview, and portions of Edenvale and Germiston. By Shaun Deacon and Peter Louw

T

HE INCREASES IN ELECTRICITY TARIFFS

for the generation of biogas. In order to reduce its

imposed by Eskom between 2010 and 2012

overall electrical power costs, consideration will be

has had a direct bearing on the operational

given to the installation of additional power factor cor-

expenditure

of

wastewater

treatment

in

Johannesburg and indications are that the annual electrical power costs could treble over the next seven to ten years.

Further increases in electricity costs will place an addition financial burden on Water Service Authorities and could impact on the environment, provision of health services, social activities at water courses and impoundments, the downstream cost of potable

Johannesburg Water manages, operates and maintains five large and one small WWTW on behalf of the City of Johannesburg

rection capacitors and the replacement of power intensive mechanical plant and machinery with more efficient equipment.

Johannesburg Water Johannesburg Water manages, operates and maintains five large and one small WWTW on behalf of the

water treatment and ultimately on certain areas of

City of Johannesburg for the central Gauteng region,

the economy.

which is split into two drainage areas by the continen-

Energy has therefore become a key driver in the mu-

tal divide. Northern and Driefontein WWTWs lie in the

nicipal wastewater services value chain. Johannesburg

northern drainage area and Goudkoppies, Bushkoppie,

has recognised the potential of CHP generation from

Olifantsvlei and Ennerdale WWTWs in the southern

biogas as a means of reducing electricity costs at its

drainage area. On average during 2012, Johannesburg s

wastewater treatment works (WWTWs).

six WWTWs treated 940 Mℓ/day of wastewater and 254

The successful commissioning of three 380 kWe gas engines at Johannesburg s Northern WWTW will provide about 12% of the work s electrical power requirements.

The

Northern Works’ biogas to energy test installation

dry tons per day of sludge, and consumed 16.4 MW of electricity (394 kWh/Mℓ of wastewater treated).

Due to the relatively inexpensive cost of electricity in

installation

will be extended to produce between 50% and 60% of the power requirements once all remaining sludge digesters have been refurbished. It is estimated that the payback period for a greenfields CHP installation generating 55% of the works needs is five years if the future increases in electricity cost do not exceed 8% per annum. However, the payback period could be reduced to about 2.5 years if the proposed Eskom tariff increase of 16% per year over the next five years is implemented.

By 2016, Johannesburg plans to generate about 60% of its wastewater treatment electricity requirements through the CHP process using sewage sludge, cell lysis and waste organic materials

JANUARY/FEBRUARY 2014

59

TECHNICAL PAPER the past, Johannesburg Water did not attempt to investigate the

reducing electrical power consumption at its wastewater treat-

technologies available for CHP generation. Effort was, however,

ment works.

spent on reducing power consumption at the WWTWs through the introduction of power factor correction, power consumption

Outcome of the initial investigations

targets and plant automation.

In March 2006, the revised Guidelines of the Utilisation and

Large increases in electricity costs between 2010 and 2012 mo-

Disposal of Wastewater Sludge were promulgated by the Department of Water Affairs and these guide-

tivated Johannesburg Water to investigate the various methods available for electrical power generation from the biogas produced at its WWTWs and to intensify its search for methods of reducing its existing electrical power demand. Energy has now become a key driver in the wastewater treatment value chain and every effort is being made to produce green

In March 2006, the revised Guidelines of the Utilisation and Disposal of Wastewater Sludge were promulgated

WWTW licence conditions. One of the ten options offered in the guidelines for sludge stabilisation, was mesophilic anaerobic digestion and this option was selected as the most economical and sustainable process for Johannesburg. Besides the process producing a well-stabilised end product, it also produces

energy and reduce power consumption.

It is estimated that by 2020, the cost of electricity for waste-

lines now form part of the Johannesburg

biogas, which can be used as a fuel in the CHP process.

water treatment in Johannesburg would have increased from

In 2009, Johannesburg initiated a feasibility study into

R93 million per annum in 2010 to above R300 million per annum

biogas to electrical energy generation on its wastewater

(excluding the proposed 16% increase per year over the next

treatment works.

five years). The potential burden placed on the Water Service

The first part of the study was to determine the risks associated

Authority s operational budgets could lead to disruption of the

with CHP operations on WWTWs and identify the most common

existing wastewater treatment operations and have a devas-

causes of CHP failure. CHP failure at WWTWs is not readily ad-

tating effect on the environment, provision of health services,

vertised and so information was not easily acquired. The infor-

social activities at water courses and impoundments, the cost of

mation obtained indicated that many CHP failures were due to

downstream potable water treatment and ultimately some areas

the lack of efficient biogas scrubbing and that the presence of

of the economy.

siloxanes in the biogas was one of the common causes of seri-

It was for the above reasons that Johannesburg began inves-

ous damage to prime movers. Siloxanes are probably one of the

tigations into ways of producing electrical power on-site and

most difficult of the biogas contaminants to quantify in the laboratory. Another common problem appeared to be the inability of WWTWs to produce a steady supply of biogas required for the efficient operation of prime movers.

The second part of the study was to determine which contaminants had to be removed from the biogas before it could be used as a fuel in CHP generation. Hydrogen sulphide, moisture, particulates and siloxanes were eventually identified as the most harmful contaminants to prime movers. The various processes available for biogas scrubbing were also thoroughly investigated and the most efficient, cost-effective and sustainable technologies identified.

Biogas sampling and analysis assisted in providing the information required for the selection of the most appropriate biogas scrubbing technologies. The selection of suitable technologies was made by Johannesburg Water and not left to the discretion of the prime mover manufacturer; however, compliance with the manufacturer s biogas quality requirements was essential for retention of the performance guarantees. Efficient scrubbing of biogas has been found to play a major role in increasing the intervals between maintenance and overhaul schedules, increasing the life expectancy of the prime movers and decreasing the number of operational failures.

The third part of the study was to determine the most suitable and cost-effective prime mover for CHP generation. Visits to wastewater treatment works in Germany and Austria, where CHP has been practiced for over 20 years on wastewater treatment works, greatly assisted Johannesburg in identifying the reciprocating engine, specifically designed for use with biogas, as the most appropriate prime mover for their needs. In determining the choice of prime mover, the following factors were taken into consideration: â&#x20AC;˘ the ability of the prime mover to produce both electrical and heat energy

60

JANUARY/FEBRUARY 2014

TECHNICAL PAPER • power efficiency of the prime mover

recommendations was presented to the

• the overall efficiency of the system

Johannesburg Water Board of Directors.

• power to heat ratio

The recommendation that CHP be pur-

• prime mover availability

sued was accepted with the proviso that

• period between overhauls of the prime

the initial installation was proven at one

mover

Africa ’s leader in natural

works before the technology was to be

• maintenance requirements

introduced at other WWTWs.

resource

• capital costs

Procurement of consulting engineering services

• operational and maintenance costs • estimated payback period.

US

The procurement of consulting engi-

Environmental Protection Agency hand-

neering services was achieved through

Information book, CHP

obtained

Catalog

greatly

2008) assisted

in the choice of the most suitable prime mover.

The final

fourth part

of

the

the

of

Technologies

(December

from

and

The appointed consulting engineers were required to draft tender documentation for cell lysis, biogas scrubbing and CHP generation

usual

tender

procedure

using

development

the 90/10 scoring system (45% functionality, 45% price

solutions

and 10% BEE). The consultants, whose tenders were successfully evaluated

the

study was to determine the volume and

for completeness and responsiveness,

quality of biogas produced at Northern

were invited to present their offers to the

WWTW. Handheld biogas monitors were

Tender Evaluation Committee.

procured to measure the quality of the bi-

The

presentations

contributed

15%

ogas produced over a period of time and

of the 45% functionality score and the

the results attained were as follows:

lowest the

Test

and

Concentration

priced

final

tender

short-listed

received

from

tenderers

was

then recommended.

Methane

62% v/v

Carbon dioxide

37% v/v

a Consulting Engineer included:

Nitrogen

0.4 ppmv

• CESA registration of the multi-discipli-

Ammonia

< 3 ppmv

Oxygen

450 ppmv

• an established office in Gauteng

Hydrogen sulphide

700 ppmv

• no commitment to any biogas scrubbing

Moisture

0.3 % v/v

Siloxanes

D3, D4 and D5 present

The functionality criteria for selection of

nary consulting engineering company

or CHP plant manufacturer or supplier • process engineering and control experience of high performance mesophilic

Nitrogen, ammonia and siloxane concen-

sludge anaerobic digesters

trations were determined in the laboratory.

• process engineering and control experi-

On completion of the investigations

ence of the collection, conveyance and

in 2010, a report on the findings and

storage of biogas

Biogas to electrical energy flow diagram

Tel: + 27(0) 11 441 1111 www.srk.co.za

JANUARY/FEBRUARY 2014

61

TECHNICAL PAPER • mechanical engineering knowledge related to CHP generation units

expected hours of operation before refurbishment of the engines was required.

• electrical engineering knowledge related to the synchronisation of an existing power supply and an

CHP contract award

on-site generated power supply

The award of the CHP contract followed the same proce-

• knowledge of the local power tariff system

dure as that for the procurement of consulting engineer-

• knowledge of biogas scrubbing and cell lysis of bio-

ing services. The only difference was that two rounds of

logical sludge • provision of references related to projects associated with mesophilic anaerobic digestion, biogas collection and storage, and the use of biogas for electrical power generation in South Africa or through an

An operations and maintenance contract formed part of the tender conditions

presentations were given to the Tender Evaluation Committee,

the

first

by

the tenderers without the prime mover manufactur-

experienced international consulting engineering

ers being present and the second by the prime mover

company to which the tenderer was associated.

manufacturers alone.

The appointed consulting engineers were required

Since the prime mover manufacturers needed to pres-

to draft tender documentation for cell lysis, biogas

ent their product only once to the Tender Evaluation

scrubbing, CHP generation and connecting into the ex-

Committee and due to the fact they had quoted to more

isting wastewater treatment grid, through to the final

than one tenderer, the presentations were held separate-

commissioning and acceptance of the installations at

ly to avoid favouritism.

all five of Johannesburg s large WWTWs. The tender was drafted as a design, supply, install, operate and maintain document for biogas scrubbing

The contracts for consulting services and the biogas scrubbing and CHP installations at Northern and Driefontein Works were awarded to:

and CHP installations at both Northern and Driefontein Works. While Johannesburg Water retained ownership of the installations, the operation and maintenance functions were required to be undertaken by the successful tenderer.

Three reciprocating engines (one standby unit) were to be installed at Northern Works and two similar engines installed at Driefontein Works. The engines were required to generate a minimum of 300 kW each and housed in soundproofed containers.

Consulting Engineering Services

Zitholele Consulting (RSA)

Main Contractor

WEC Projects (RSA)

Subcontractors Civil

Renniks Construction (RSA)

Electrical

Zest Energy (RSA)

Control and instrumentation

ERTEC (RSA)

Biogas scrubbing

Applied Filter Technology (US)

Reciprocating engines

Dresser Rand – Guascor (Spain)

Biogas scrubbing requirements were based on the following methods of contaminant removal: • hydrogen sulphide removal ‒ wet scrubbing/biological treatment

The successful contractor, WEC Projects, offered the following processes in its tender:

• siloxane removal ‒ activated carbon • moisture removal ‒ refrigeration/chilling.

Biogas scrubbing

Biogas monitoring equipment was to be installed

Biogas is passed through a wet scrubber for hydrogen

upstream and downstream of the biogas scrubbing

sulphide removal followed by coalescing filtration for the

installation and capable of monitoring:

removal of free moisture. The biogas is then passed to a

• gas flow

blower for regulation of the delivery pressure and on to a

• methane content

glycol chiller, where the remaining moisture is removed.

• carbon dioxide content

Thereafter, the temperature of the biogas is raised to en-

• hydrogen sulphide content

sure that condensation does not occur before the biogas

• water vapour.

is passed through an activated carbon filter for siloxane

The presence of siloxanes was to be determined by

removal. The final stage of scrubbing is by passing the bi-

regular sampling and laboratory analysis of the biogas.

ogas through a particulate filter. The quantity and quality

Other information supplied in the tender document

of the biogas is monitored on-line, before and after the

included altitude, ambient temperatures, weather

scrubbing process. See diagram.

conditions, relative humidity, description of the general site conditions and details of the existing power

Reciprocating engines

supply installation.

The tender document required that only reciprocating engines, specifically designed for use with biogas, be offered.

Operations and maintenance contract

Main and alternative offers were received for reciprocating

Due to Johannesburg s lack of operational and maintenance experience in biogas scrubbing and CHP generation, an operations and maintenance contract formed part of the tender conditions. The length of the contract period was determined from several reciprocating engine manufacturers estimations of the

62

engines and the offer accepted was for

This paper has been edited and abridged for publication.

For references or information about the complete paper, please contact the editor at maryke@3smedia.co.za

JANUARY/FEBRUARY 2014

the supply of Dresser-Rand Guascor engines. The accepted offer allowed for a separate step-up transformer for each reciprocating engine and for the engines to be housed in soundproofed containers.

PROFILE

SOFTWARE

Condition monitoring software launched Johannesburg-based Prei Instrumentation represents the most technological advanced products in its field – making it a successful leader in the process, measurement and control industry in South Africa. Maryke Foulds speaks to managing director Steve Herbst, about its latest product offering, Condition Monitoring Software from Setpoint LEFT Metrix Setpoint Vibration monitoring system BELOW The new Digital Probe Driver

Setpoint CMS

pro-

vides users with unparalleled security through a robust, multi-layer

K

EY TO Prei Instrumentation s

comprehensive machinery analysis tools.

model that is considered the best in its

product range is its technical

They are:

class. It is specifically designed to work

support for online, portable and

• PI Process Book, which is an off-the-shelf

with firewalls, data diodes and multi-tiered

laboratory analysers for the po-

application from OSIsoft that is used in

networks to meet industry s most stringent

thousands of applications worldwide.

data security requirements ‒ even those in

table, waste and industrial water markets as well as rotating machinery monitoring, protection, prediction and control.

• CMS Display, which effectively extends the capabilities of PI ProcessBook to view

the nuclear power sector.

In

conclusion,

Herbst

says:

Because

Setpoint Condition Monitoring Software

waveform data and support the special-

Setpoint CMS is built on OSIsoft s PI System,

(CMS) provides an online, continuous

ised plot types useful to machinery diag-

you have the confidence of a system with

collection of vibration and conditioning

nostics, engineers and other tasked with

tens of thousands of installations worldwide

data from connected Setpoint racks, allow-

assessing machinery condition. These

and multiple generations of enhancements.

ing trending, diagnostics and predictive

plot types include orbit, time base, spec-

Most industrial customers rely on the PI

maintenance of monitoring machinery,

trum, Bode, shaft centreline and others.

system for their real-time data and historian

says Herbst.

The PI System infrastructure used by

functions than any other system.

The software uses the OSIsoft PI System as its infrastructure, communicating directly with each Setpoint rack using an open pro-

Prei Instrumentation: new appointments

tocol and storing the data in a process information (PI) database. Both the static and dynamic (waveform) data is captured under a steady-state and transient conditions.

Up to 300 channels of vibration data are supported by a single CMS server. Since a single Setpoint channel can return multiple data types simultaneously, a 300 channel

2

014 IS SET TO BE an exciting year at Prei Instrumentation. Not only has it launched new prod-

ucts, but a planned move to an exciting new premises is also on the cards.

This year also sees some new appointments at the company.

system can correspond to more than 5 000

Previous managing director Dave Cox

distinct static and dynamic data types ‒ all

has been replaced by Steve Herbst,

of which can be captured and archived by

who was previously the group director.

a CMS server.

Herbst has been with Prei for 16 years

LEFT Steve Herbst, managing director RIGHT Cheryll Smith, financial director

Data residing in the CMS Server is viewed

and is a significant shareholder. Cheryll

director and has been with Prei for just

using two applications. These work hand

Smith has been promoted to financial

over 10 years.

in hand with one another to provide

JANUARY/FEBRUARY 2014

63

INTERNATIONAL

Yorkshire Water chooses local company says Stephen Herndlhofer, head of Data Services at Yorkshire Water.

BMA was selected for this seven-year contract, one of the largest business analytics software deals in the UK Utility sector to date, ahead of a wide range of the UK s leading blue chip consulting and technology companies.

We have spent over two years formulating our business analytics strategy, which has included a peer review

by Cranfield University

says Herndlhofer.

BMA was

selected to support the delivery of this strategy due to the uniqueness of its partnering approach, clear focus on value creation and the maturity of its technology.

The independent review and critique of BMA s approach, conducted for Yorkshire Water by their strategic research partner

Business Modelling Associates (BMA) has been appointed as business analytics partner for the development of an integrated Risk and Cost Modelling capability.

B

MA, A LEADING business analytics, supply chain design and solutions development firm with operations in Africa and the UK, announced that it has been selected by Yorkshire Water for

the development of an integrated Risk and Cost Modelling capability. Yorkshire Water, part of the Kelda Group, is one of the UK s largest water utility companies providing water and wastewater services to five million customers in the north of England.

The development of an integrated suite of risk and cost models that accurately represent the business and

ABOVE Yorkshire Water is investing £3.8 billion over the next five years to maintain its network of over 700 clean and waste water treatment works and more than 96 000 kilometres of water and sewerage mains.

Cranfield

University,

concluded:

Yorkshire

Water has an internationally leading approach to risk management and strategic cost modelling that is approaching best in class for the Utility sector.

BMA s co-founder and director, Rod Stout, says: We are very excited to be embarking on this journey with Yorkshire Water to develop a long-term internal business analytics capability that could revolutionise the way the company optimises its operational and strategic decision making processes. After a strenuous international due diligence process, we are delighted that Yorkshire Water has selected BMA as its business analytics partner.

The primary objective of this project is to create a business analytics capability within the Kelda Group. BMA will support the development of expertise throughout the client user community to the extent that the client will ultimately become self-sufficient in the ongoing development and maintenance of the Yorkshire Water integrated modelling suite, says Stout.

BMA will utilise River Logic s next generation business

the context within which we operate will support a

analytics software, Enterprise Optimizer, to build a series

technological and cultural change in the way in which

of bespoke yet integrated models that will allow Yorkshire

we plan and operate our business. Applications for

Water to more accurately determine and forecast risk and

the modelling technology are diverse in nature to the

cost throughout the organisation. This enterprise-wide

extent that we expect considerable consolidation of

integrated modelling framework will help Yorkshire Water

existing bespoke modelling applications and reductions

solve business challenges at the strategic, tactical and

in

operational level.

third-party

modelling

expenditure

over

time,

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