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
Nalco technologies empower vigorous and effective mine water management.
Nalco can help you use less, save more, and effectively treat water returned to the environment. Look to the highly skilled Nalco sales engineers who are ready to address your mine water challenges, and reduce your operating costs with economically and environmentally sustainable water management solutions. Call Nalco Africa today.
Nalco Africa Operations Building 14, Ground Floor, Greenstone Hill Office Park Emerald Boulevard, Greenstone Hill, South Africa Tel: +27 10 590 9120 Fax: +27 10 590 9130 nalcoafricareception@nalco.com www.nalco.com/sa Š 2013 Ecolab USA Inc. All rights reserved
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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Does your company have an environmental, analytical or plant operations treatment challenge? Identifying potential problems with water and wastewater is Talbot & Talbot’s area of expertise. Our team of specialists are dedicated to creating and implementing scientifically engineered solutions, that reduce your environmental footprint and conform to legislation. The team is also proactive in maintaining your water or wastewater treatment plant and identifying alternative energy resources that are key to driving down production costs. So if you are looking for solutions, call Talbot & Talbot - it’s a simple choice.
+27 (0) 33 346 1444
t
talbot@talbot.co.za
t
www.talbot.co.za
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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Tel: +27 (0)11 233 2600 Share Call: 086 003 3300 www.3smedia.co.za
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
PO Box 751781 Gardenview 2047 South Africa
Tel.: +27 11 616 7999 Fax: +27 11 616 8355 abeco@icon.co.za
www.abecotanks.co.za
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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