MechChem Africa June 2018

Waste management for environmental peace of mind Mech Chem JUNE 2018 AFRICA

This month: Warman pumps: 80-years of continuous development

Turbo machines and reverse engineering

Biorefinery facility to address waste challenges

Are hydrogen-powered trains the future of rail?

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Pump systems, pipes, valves and seals 8 Warman pumps: 80-years of continuous development

P U B L I C A T I O N S CR O WN

In celebration of the 80 th anniversary of Charles HaroldWarman’s first Warman ® Pump, Pieter Jordaan,Weir Minerals Africa Sales Director for Africa and the Middle East, talks about the history and evolution of the Warman slurry pump.

10 Slurry pumps for University of Pretoria laboratory 12 Pumps systems 101: Landlords and pumping systems 14 The liquid ring vacuum pump 15 Stainless steel submersible pumps added to rental fleet Localisation, manufacturing, production and food processing 16 Turbo machines and reverse engineering

Published monthly by Crown Publications cc Cnr Theunis and Sovereign Streets Bedford Gardens 2007 PO Box 140, Bedfordview, 2008 Tel: +27 11 622 4770 e-mail: mechchemafrica@crown.co.za www.mechchemafricamagazine.co.za Editors: Peter Middleton e-mail: peterm@crown.co.za Glynnis Koch e-mail: glynnisk@crown.co.za Advertising: Brenda Karathanasis e-mail: brendak@crown.co.za Design: Darryl James Publisher: Karen Grant Deputy publisher: Wilhelm du Plessis Circulation: Brenda Grossmann The views expressed in this journal are not necessarily those of the publisher or the editors. P U B L I C A T I O N S CR O WN P U B L I C A T I O N S CR O WN 2015/02/10 01:17:09PM

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MechChemAfrica visitsACTOMTurbo Machines in Sasolburg,a division ofACTOM (Pty) Ltd and talks to Mark Gulbis,project engineer, about his division’s expertise in the maintenance repair and reverse engineering of high-speed rotating machines. 19 SA-manufactured mine winder for Canada 20 Food safety: Winning consumer confidence Power generation, sustainable energy and energy management 22 Electrical heat tracing for energy conservation Dirk Venter from eltherm South Africa, a heat-tracing specialist, highlights the energy savings and reliability advantages of using electrical heat tracing (EHT) solutions to maintain fluids at an optimum viscosity. 24 Towards a sustainable energy mix for Africa Petrochemical, oil and gas 26 Biorefinery facility to address waste challenges The South African government, through the CSIR has launched a R37.5-million biorefinery facility in Durban to enable extraction of maximum value from biomass resources. MechChemAfrica talks to the CSIR’s Bruce Sithole, the chief scientist and manager of the facility. 28 Oil & gas industry poised for revenue growth 29 On-site oil treatment saves transformers Environmental, waste management and cleaning technologies 30 The evolution of recycling processing equipment A new range of small, mobile crushers and screens from EvoQuip, distributed in South Africa through ELB Equipment, is about to represent a big opportunity for businesses to explore new opportunities in processing, especially in the areas of recycling and waste management. 31 ROSE Foundation – protecting our dwindling water resources Innovative engineering 38 Are hydrogen-powered trains the future of rail? A hydrogen-powered train that uses off-gas from industrial processes could hold the key for sustainable transport of the future: writes Robin Whitlock for World Steel. REGULARS 2 Comment: Raising food-processing standards 4 On the cover: Best practice waste management for environmental peace of mind MechChem Africa talks to EnviroServ CEO, Dean Thompson, about responsible waste management, the company history and some successes. 6 SAIChE IChemE News: Biomimicry: learning from evolution in nature 32 Product and industry news: Nadjar expands beyond grinding 40 Back page: Robot car leaps towards automatic driving

Transparency You Can See Average circulation January-March 2018: 4 815

Printed by: Tandym Print, Cape Town

Front cover: EnviroServ +27 800 192 783 annemaried@enviroserv.co.za www.enviroserv.co.za

June 2018 • MechChem Africa ¦ 1

Peter Middleton Raising food-safety standards A s a result of the ‘world’sworst ever’ listerio- sis outbreak earlier this year, Tiger Brands has completely shut down four of its plants: the Value Added Meat Product facility in Pretoria; the Enterprise Foods factories inPolokwane and Germiston; and its Clayville abattoir.

Herewehave ten ‘random’ causes of contamination tragedies, listeriosis being an11 th , and the list does not offer any easy way to predict the next incident. Tiger Brands CEO, Lawrence MacDougall, is cur- rently calling a food safety council to be set up and for the government to establish newsafety standards. “In a post listeriosis environment, youwould probably havehoped therewere industry standards and that the department of health and industry was collaborating closer to keep pacewith developments in the industry and within immune deficient individuals,” he told City Press’ Justin Brown. MacDougall is calling for a change in the current standard, which sets limits of less than 100 colony- forming units (cfus) of viable bacteria per 100 grams of product. Less than 10 cfus in 25 grams of product is the next step up, but MacDougall points out that, internationally,Canada,AustraliaandNewZealandare suggestingthatthisnumbershouldhavetobeachieved “at the end of the shelf life for that particular product, not during production”. After the horse has bolted, perhaps, but it is good to see a food-industry captain championing improved standards. In this issue, we include a food-processing feature in which Afrox’s Hendrik Pretorius talks about how consumer demand is driving the food industry to- wards offering fresher and healthier food products. This is changing food packaging and the entire cold chain, where it is now possible to safely package and preserve fresh food for much longer and to transport it directly to supermarkets from farms and abattoirs. While Afrox’s contribution is in the development of gas atmospheres that best prevent the deterioration of different food products, Pretorius acknowledges that it is the power of the consumer that is driving food producers towards healthier and safer options. Perhaps a South African food contamination in- cident was inevitable and Tiger Brands’ Polokwane factory was a random weakest link. But let’s not limit the solution to cleaning up one company. Wemust all raiseour standards: at farms, packaging plants; transport depots; in trucks; at abattoirs; and at all of our food and beverage processing plants. And as consumers, we should be more proactive in keeping our food safety officers and all of the beneficiaries of our supermarket-spend more ac- countable, by insisting on transparency and favouring those that place food safety standards and our health above profit. q

There have been 978 cases of listeriosis and over 200 confirmed deaths across the country. The source has been tracedback topolonymade at theEnterprise Foods factory in Polokwane – the other Tiger plants having been shut down for “precautionary measures” while the company grapples with root causes and consequences. “While all facilities have halted production, our people are at work assisting with various other func- tions within the factories, predominantly related to deep-cleaningprotocols and routinehygiene activities that are still required for food production facilities,” said Tiger Brands spokesperson Nevashnee Naicker. Todate,theoutbreakhasofficiallycostthecompany R415.2-million,whichdoesnotincludetradinglossesor potential litigations settlements –and the factories are not expected to reopen before October, 2018. Also affected is the local pork industry. ‘ThePeople First Piggery in the gritty South African mining city of Rustenburg used to slaughter 150 pigs each month. It’s now down to zero,’ reads a June article on Fin24 , which goes on to report that the industry has cut at least 2 000 jobs, pork prices have dropped to four- year lows (down 40%) and small farmers are at risk of closing down. Although the listeriosis outbreak is undoubtedly tragic, I find it remarkable that the ‘worst ever’ tag can be applied to the case. I found an article published in 2013 entitled ‘10 Worst Food Contamination Incidents Ever’ which lists a 1974 incident involving wheat con- taminated with charmac seeds in Afghanistan as the worst. Over two years, this led to around1600deaths and affected up to 7 800 people in total. A reoccur- rence in 2008 killed a further ten people – which has got to be much less forgivable. Completing the worst 10 list are: mustard oil con- tamination in Delhi (1998); toxic alcohol in Bengal (2011); dried milk poisoning and mercury poisoning in Japan (1955 and 1956); a melamine-contaminated powderedbabymilkscandalinChina(2008);Aflatoxin- contaminatedmaize (2004); imported grain (from the US and Mexico) contaminated with a mercury-based fungicide in Iraq (1971); arsenic contaminated beer in England (1900); and toxicoil syndrome inSpain (1981).

MechChem Africa is endorsed by:

2 ¦ MechChem Africa • June 2018

Best practice waste management for environmental peace of mind

EnviroServ is SouthAfrica’s oldest and most respected waste management solutions provider. MechChem Africa talks to the company’s CEO, Dean Thompson, profiles the company and highlights some successes.

S ince EnviroServ opened its doors in 1979 it has pioneered many waste management solutions, some of which are still recognised as best practice today. “We strive to look for bet- ter ways of doing things. From our forward thinking founderswhohadsocial consciences, this has become deeply embedded in our culture – and these are the kinds of people we still employ,” says Dean Thompson, the company’s CEO. Today, EnviroServ serves all nine prov- inces of South Africa and several African countries across all industries. “But we started out on a much smaller scale, as a privately-owned door-to-door waste collec- tion and disposal service with a willingness to tackle difficult operational conditions and to service disadvantaged black townships during turbulent political times,” Thompson tells MechChem Africa . In 1990, the company commissioned its first industrial waste disposal site at Holfontein in Johannesburg, which was es- tablished inaccordancewith theDepartment of Water Affairs’ Minimum Requirements. Today, the Holfontein Hazardous Waste Disposal Site treats and disposes of high- hazard wastes in compliance with a waste management licence issued in terms of

the National Environmental Management: Waste Act, 2008. Holfontein provides an integrated, full- service waste management facility that can receive, store, re-use, recycle, recover and treat Type 1 (high risk) to Type 4 (inert) wastes, as well as provide for the final dis- posal of both general and hazardous wastes in sites with the appropriate containment barrier design. Turning back to the company’s legacy, Thompson says that the acquisition of Waste-Tron in 1996 began EnviroServ’s expansion in South Africa, giving the com- pany a strong foothold in KwaZulu-Natal. Further acquisitions include: Waste-tech in 1997, which firmly established EnviroServ’s formidable national presence; ConquipHire, which specialises in compaction plant and equipment and now operates as an internal EnviroServ company at its landfill facilities and on contract for clients; the 2003 acquisi- tion of Abzorbit, an emergency high-risk spill response company; and EnviroServ Tailings, a company specialising in the construction and management of tailings dams for mines. Among the waste streams accepted by landfill sites such Holfontein are industrial chemicals, condemned foodstuffs, contami- nated soils and general household waste.

These sites are classified as H:h – Class A landfill for the safe disposal of high-risk chemical substances – and they are licensed by the Department of Environmental Affairs, which specifies the types of waste that can be processed. Where needed, EnviroServ has also se- cured Waste Management Licences to oper- ate on-site effluent treatment plants, for the treatment of leachate, for example, which is done according to legally prescribed rules governing thequantityandqualityof leachate than can be processed and disposed. EnviroServ is required to conduct regular internal audits, pay for external audits by an independent company, and allowaccess to its sites at any time for the Department to con- duct any audit or inspection as it chooses. In addition, EnviroServ itself conducts routine surveillance in the following areas: ground and surface water monitoring; occupational health monitoring; air quality monitoring; worker exposuremonitoring; and landfill gas monitoring. Some of these are license or legal requirements. All 11 owned or managed landfill sites in South Africa and Africa are run according to international best-practice standards with the aimofminimising risk to the environment through responsible management practices. Minimum impact to the environment is the company’s primary goal, with reduction, reuse, recycling, and recovery being some of the tools used to achieve this. The landfill facilities aredesigned toexact- ing specifications by civil engineers, and are operated andmonitoredby expert engineers, scientists and other industry specialists who are tasked with ongoing geo-technical assessments of soil and ground structures, geo-hydrological assessments of ground

Before waste can be disposed of by EnviroServ, it is assessed by the company’s laboratory in Johannesburg, which was the first in South Africa to receive SANAS accreditation.

4 ¦ MechChem Africa • June 2018

⎪ Cover story ⎪

Above: As a company whose waste management strategy includes diverting waste from landfill, EnviroServ has a number of initiatives that ensure the reuse, recycling and reduction of waste. Right: A company’s waste plan needs to consider strategic placement of collection containers as well as staff and logistics to empty full containers or assemble full containers at bulk transfer areas. Below right: EnviroServ’s Industrial Cleaning Services has a fleet of vacuum trucks to offer industrial services such as sump desludging to large, medium and smaller-sized customers. water, and scientific testing of the nature of waste that is disposed of. The structure of the landfill cells conforms to industry regulation specifications, and all cells are built with double composite liners that includeplastic high-densitypolyethylene (HDPE)membraneswithnaturallycompacted clay liners (CCL). BeforewastecanbedisposedofbyEnviro­ Serv, it is assessed by the company’s labora- tory in Johannesburg. In February 2012, this waste laboratory became the first in South Africa to receive SANAS accreditation. It is accredited according to the ISO/IEC 17025 standard for waste analysis and is able to of- fer expert advice on the testing and handling of hazardous waste materials. The laboratory offers a full range of environmental testing services to assess solid, liquid and sludge waste. The work of the laboratory can also guide decisions on waste processing options – whether re-use, recycling or recovery are suitable or pos- sible in any particular instance, for example. It is also able to guide decisions on the safe transportation, handling, storage, treatment and disposal of the waste. EnviroServ is certified and compliant with international standards such as ISO9001 for quality and 14001 for environmental man- agement; the OHSAS 18001 safety standard as well as the Chemical & Allied Industries Association Responsible Care and Safety & Quality Assessment System (SQAS). “We also take responsibility for rehabilita- tion and post-closure monitoring of all our

end-of-life sites after they have been decom- missioned,” says Thompson. “Our services, products and solutions are comprehensive, enabling us to offer customers full turnkey or specially tailored options relevant to their specific operations and industries, including: waste assessments, analysis and classification, including onsite wastemanagement; collection, treatment and disposalofawidecategoryofwaste;industrial cleaning,includingtheapplicationofappropri- ate absorbent spill control products to deal withspillscausedbychemicalsandmarineand aquatic incidents; and tailings management.

“From being the first and only company to tackle some of the most difficult waste management issues in South Africa, we’ve come to understand that sustainable waste management is not a finite concept. It evolves with society’s needs, habits, and awareness of health and environmental prosperity,” says Thompson. “As a result, EnviroServ is continuously improving. New lifestyles, new technologies, newwaste, largerwaste volumes, new legisla- tion and newwaste management thinking all create fresh possibilities and challenges,” he concludes. q

June 2018 • MechChem Africa ¦ 5

Biomimicry: learning from evolution in nature Following the SAIChE IChemE AGM on April 10, 2018, the Gauteng member group held its annual dinner at the Wanderers Club in Johannesburg. MechChem Africa attends and highlights the presentation by biomimicry practitioner and chemical engineer, Yuma Langenbach.

“ H umans are clever, but without intending to, we have cre- ated massive sustainability problems for future genera- tions. Fortunately, solutions to these global challenges are all around us. Biomimicry is an approach to innovation that seeks sustainable solutions to human challenges by emulating nature’s time-tested pattern,” begins Langenbach. She says that the classic process engi- neering development cycle involves putting materials through a process to produce a product. It’s a linear model, with some ad- ditional complications, such as optimising the use of energy and the activation conditions for specialised processes. “But almost all of our engineering process endeavours are inef- ficient and produce undesirable waste along with the intended product,” she says. Combined global production is currently too much for the environment to sustain. Industrial processes are intensive with re- spect tomaterials, energy and environmental pollutants, all of which puts our planet at risk. “Clearly, we need more dramatic and innova- tive solutions to ensure a safer environment,” Langenbach says. Returning to her biomimicry theme, she says that humans have been living on Earth for around 200 000 years, but the first living cells date back some 3.8-billion years and, over this time, thesehavedeveloped themost sustainable and efficient ways of surviving.

“What better model, therefore, than the naturalworld to learnabout efficient and long lasting solutions?” she asks. Shecitesvariousbiomimicryopportunities that havealreadyemerged fromstudies of the bio diverse natural world: • Wetland eco-systems are teaching us about filtration and water treatment. • The structures andenergyflows in tropical forests are inspiring cities of the future. • Leaves and plants capture energy every day, inspiring more efficient renewable energy solutions. • Termite mounds and how they regulate temperature are being mimicked to im- prove the energy efficiency of buildings. • The way the coral reefs are built from car- bon dioxide and calcium is being imitated to improve cement-production processes by capturing the CO 2 emissions and reus- ing it to produce calcium carbonate. • Mushroomfungi havebeen found tobreak down hydrocarbons, which makes them ideal for oil spill remediation. Another innovative example Langenbach presentedwas amaterial developed tomimic the skin of a shark. “Shark skin is made up of countless overlapping scales called dermal dentilswithgroovesrunningdowntheirlength to align with the water flow. These grooves disrupt the formationof turbulence, while the roughshapealsodiscouragesbacterial biofilm growth, which cannot form on this surface. “This has been replicated for use in swim- suits and for the bottom of boats – and the technique is now being used in to create sur-

facesinhospitalsthatresistbacteria,”shesays. She goes on to describe the Lily impeller developed by PAXScientific, which replicates nature’s spiral flow pattern to significantly improve the performance and energy usage when mixing water in storage tanks. This Lily-inspired impeller is only 21 cm long, yet it is capable of circulating millions of gallons of water with the same energy footprint as three100W light bulbs. “Naturenevermoves in a straight line. It always prefers a spiral path, which turns out to be the path of least resistance/fluid friction,” Langenbach says. “All these naturally occurring processes occur at ambient temperatures and pres- sures,” she notes, adding: “The number one thing we can learn from nature is that life involves changing conditions. Sunflowers trackthesunduringthedayandplantsalltend to seek ways of stabilising themselves when the climate changes. And the way organisms on forest floors pass on their waste for use by other organisms can teach us a lot about how to create and manage a more circular economy,” she argues. “We humans are a social species,” she says. “We need to work together to innovate solutions for our current survival, for that of the environment and for future generations. “Biomimicry innovations are the future. Bio-architecture and -structures; biomimicry in textile and chemical manufacturing; new power and transportation systems; and a host of waste management solutions are just a fewareas that are enthusiastically adopting biomimicry principles,” she concludes. q

The proprietary Sharklet TM surface technology has replicated the advantages of sharkskin for use in swimsuits, the bottom of boats and to create surfaces in hospitals that resist bacterial growth.

6 ¦ MechChem Africa • June 2018

⎪ SAIChE IChemE news ⎪

National AGM and president’s report activity happens,” Sheridan says.

T he SAIChE IChemE annual general meeting was held on 10 April 2018 at theWanderers in Illovo, Gauteng, startingwith the association’s presi- dent, Craig Sheridan, welcoming attendees, going through the minutes and the agenda, before delivering his Annual Report for the 2017 year. SAIChE IChemE is small voluntaryassocia- tionofprofessionalsandassuchcannotafford a full-time executive with support staff to manage and run the institution as some of the larger professional associations do. It relies on volunteers and voluntary committees to handle its activities. “What we are pleased to note is that SAIChE IChemE has not had any radical or negative changes. We have remained a stable entity, offering our niche suite of services to our profession, which at a personal level culminates ingetting chartered as a full member,” reported Sheridan. “Bronwynne Ferreira, our CPD expert, is leaving and we offer our gratitude for her services over the years in getting courses accredited. Fortunately, she is still an active member. In her place, we welcome Albert de Bondt and HamiedMazema who are actively developing new policies towards improving the CPD service,” he continued. The South African Journal of Chemical Engineers continues to attract and publish high quality papers through its peer review process and publication on the ScienceDirect platform. This is a fully open-access jour- nal, which means that anyone, including all SAIChE IChemE members, can down- load papers for free. “We wish to thank ProfessorMilanCarsky for his on-going hard work as Editor-in-Chief, and we welcome Professor ThokoMajozi in his role as deputy editor-in-chief.” Sheridan said that he was pleased to an- nounce that planning has begun for SACEC 2020. The conference will be staged as an international conference, to be held at the University of the Witwatersrand, Johannesburg. “Elly Obwaka continues to assist with the membership committee. As part of the servic- es we offer, corporate members still get free CPS accreditation. Michelle Low continues to serve as the head of the communications portfolio. She maintains the Facebook page, and does an excellent job of herding and ral- lying everyone to provide photos of events, and to keep in touch with MechChem Africa ,” he continued. “The branches remain active and repre- sent SAIChE IChemE at a regional level. We wish to offer a special word of thanks to the branches, since they arewheremost Institute

“To all our members, many thanks for your support and I would like to encourage all to get more involved in SAIChE IChemE activities. Above all, SAIChE IChemEcares for your professional development and security,” Sheridan concluded. q

“SAIChE IChemE remains financially sound as a going concern and continues to be a vibrant institution in fulfilling itsmission. Themembership remained steady andwe are continuously building to grow the institution.

Japie Scholtz is awarded Honorary Fellow membership of SAIChE IChemE and thanked for his contribution to chemical engineering and the Institution by its president, Craig Sheridan.

The SAIChE IChemE annual general meeting was held on 10 April 2018 at the Wanderers Club in Illovo.

SAIChE IChemE Gauteng Branch AGM and dinner 2018 For the second year in a row, the Gauteng branch AGM 2018 was held directly after the national AGM at the Wanderers Club with some members electing to attend both events. products. Therewasmuch discussion after the talk about a wide-ranging number of topics, including questions by members about the current regulatory environment for engineers. The 2018/2019 Gauteng branch com-

Attendance of the branch AGM was good andwe electedKasturie Premlall as a newmember while Zita Harber and Jefrey Pilusa have stepped down at the end of their terms. The chair, Carl Sandrock, gave a summary of the previous year’s events, noting that attendancehadbeen improving as the schedule of the events becamemore regular. The speaker, Yuma Langenbach, gave a very interesting talk on biomim- icry, relating natural artefacts to designed

mittee members are: Chair: Carl Sandrock

Vice Chair: Danielle Bearman Secretary: Doctor Tshikotshi Treasurer: Linda Jewell Public Relations: Qasim Fakir Catering: John Bewsey

IChemE Contact: Nirvanna Ramparsad Unassigned portfolio: Shaan Oosthuizen, Michael Daramola, Celo Mausse

June 2018 • MechChem Africa ¦ 7

In celebration of the 80 th anniversary of Charles Harold Warman’s first Warman ® Pump, Pieter Jordaan, Weir Minerals Africa sales director for Africa and the Middle East, talks about the history and evolution of the Warman slurry pump. Warman pumps: 80-years of continuous development

D r Charles Harold (CH) Warman started his career as a young engineer in the gold mines of Kalgoorlie in Western Australia in 1934. “While working on the mine, CH Warman came upwith the concept of a slurry pump with replaceable liners,” says Jordaan, “the ideabeing that, whilematerial will always wear away, if a liner is used thewornmaterial can easily be replaced,” he adds. Charles Warman also realised that by engineering a pump with individual compo- nents that are easily replaceable, he could extend the life span of the pump. “That way, a long life can be achieved from each set of wear components aswell as the pump casing,” Jordaanexplains, adding that, indesign terms, this is calledmaximising thewear tostructural material ratio. “If thewear to structural materials ratio is low, thematerial available forwearwill have a relativelyhighercost,asalargerportionofthe component will not be utilised for wear but rather for structural purposes. Using a higher ratio of wearmaterial, therefore, reduces the total cost of ownership of the pump,” Jordaan tells MechChem Africa .

“This was CH Warman’s revolutionary idea. He invented the concept and, in 1938, used it to build the first ever slurry pumpwith replaceable liners. “From there, he started a business called Warman Equipment, which attracted inter- est from mines all over the world, including Africa. Then in 1969, Charles Warman sold a portion of Warman Equipment to the min- ing company Peko-Wallsend, while Charles Warman himself kept the CHWarman Pump Group portion of the company as an exclusive operation forAfrica and theMiddleEast. “The reason he kept it was because of the aggres- siveoresfoundinAfrica.CharlesWarmanwas passionate about R&D and he believed that if he could develop pumps for African ores, then these would be better suited to mining operation everywhere else in the world,” Jordaan explains. In 1999, the UK-based Weir Group acquired what was then called Warman International. The CHWarman Pump Group in South Africa remained independent, until 2007, when it too was brought into the Weir fold. “And, along with Envirotech, which has been part of theWeir Group since 1996, this

now constitutes the current pump offering of Weir Minerals Africa,” Jordaan informs MechChem Africa .

Continuous improvement Early development by Charles Warman quick- ly led to the develop- ment of the Warman ® AH centrifugal slurry

pump range, which has been the leading Warman pump for over half a century. “Using feedback

f r om ou r cus - tomers and data from engineers, we have contin- ued to upgrade and improve this heavy duty pump over the years, by targeting important issues such as wear life, hydraulic design

and the material composition of the liners. “At the starting point of pump develop- ment is hydraulics, to keep the transfer of kinetic energy tofluidflowas efficient as pos- sible. Impeller design, internal profiles and the positioning of the wear materials to reduce wear rates and ensure themaximumpossible wear life are all critical design considerations. “In principle, we are always striving to achieve the longest possible period between liner replacements. The longer this period can be stretched, the lower the operational costs of the pumping operations will be. Both the hydraulic efficiency and the materials used are critical in achieving this,” he explains. “Some applications work very well with rubber liners, but others need metal liners – and if these are swapped around, the results may be disastrous. Today we have numerous different material options, hard-chrome metal, corrosion-resistant steel, natural and synthetic rubbers, polyurethanes – and we even offer some ceramic liner components,” Jordaan tells MechChem Africa .

A Warman AH 14/12 pump installed at a dredging plant.

8 ¦ MechChem Africa • June 2018

⎪ Pump systems, pipes, valves and seals ⎪

Above:

® slurry pump with replaceable

liners.

Right: A Warman MCR 550 installed in a mill discharge operation. Since the wear rate increases exponentially with speed, the larger MC/MCR pumps are designed to meet the duty requirements at reduced speeds.

Left: The WRT impeller and throatbush upgrade for Warman AH pumps, due to the enhanced hydraulics involved, results in significant improvements in the wear life of the AH pump range. “All of these are carefully chosen and tested for use in specific applica- tions to get optimal wear from the liners for each client’s slurry pumping application,” he assures, adding: “While energy efficiency is always a driver, slurry pumping is not a

adjustment of the gap between the impeller and the throat bush tominimise recirculation and associated wear,” he explains. “We have also applied the same principles to our vertical spindle pumps, and the WBV range was introduced a few years ago. One of the unique features of this pump is that it creates agitation flowunderneath the impel- ler to disturb thick settled mud so that it can be easily pumped as slurry. We used to use mechanical agitators for this, but the new WBV relies on hydraulic agitation,” he notes. Also, recently released is the Warman ® DWU range of dewatering pumps for pump- ing lightly contaminated water typical of the dewateringduties.“Thisisabespokepumpfor dewatering pits and shafts when some solids are present. Using materials of construction from our slurry pump experience, the DWU range offers high-headoptions of up to130m per stage. And a newone-piece bearing frame has been designed for optimum alignment of the bearings, seal and impeller with the front liner. This further reduces wear rates and lowers stockholding,” he adds. “Also, we have theWarman ® MCandMCR pumps, which are purpose designed mill- circuit pumps, designed for the aggressive wear associated with milling. The particles involved in mill-circuit slurries typically have sharp, freshly broken and coarse edges that are highly abrasive and often have high den- sity – and mill-circuit pumps are usually the biggest pumps on a plant. “This is such a different application that it really pays for a customer to be using a be- spoke pump tailored for mill duty. The larger MC/MCR pumps are designed to perform the duty at reduced speeds. The wear rate of impellers and liners increases exponentially with pump speed. So by selecting a larger pump that can run at a slower speed to meet the production requirements, the wear rate

can be significantly reduced,” Jordaan tells MechChem Africa . “Across the life of a mill pump, there is always a balance between the wear compo- nent costs and the initial capital or purchase costs. If one looks at the ratio of these costs, the initial capital cost will amount to around 10%of the total. Soup to90%of the total cost of ownership is taken up in replacementwear liners and spares. “Shifting that balance a little by increasing thepump’s capital cost canhaveahuge impact on the cost of the wear components across the lifetime of themine,” he notes, adding that this does not take intoaccount anydowntime, because a whole mill circuit may have to be taken offline while the pump is refurbished. “If a bigger pump results in one less shutdown over a period, the uptime and cost of spares savings that accruewill far outweigh the initial cost of the larger pump,” he argues. Jordaan says that Weir Minerals has achieved some significant successes with their lined mill-circuit pumps. “Through our Integrated Solutions offering, we investigate entire mill circuits and recommend process changes. By introducing theMC/MCR pump, adjusting the pump and pipe lining materi- als and rightsizing downstream equipment such as hydrocyclones, we are often able to prove very significant total cost of owner- ship savings, along with significant process improvements. In cases where a mine’s production has been increased from its design duty point, Integrated Solutions has achieved significant savings byoptimising thewear lifeon themill- circuit equipment,” Jordaan says. “At the heart of a host of mill-circuit and mine pumping applications all over the world are the descendants of an 80-year old Warman slurrypumpwith replaceable liners,” he concludes. q

one-solution technology. Youhave to match the whole pump to the medium being pumped and to the conditions that apply on each mine.” In recent times, Wear Reduction Techno­ logy (WRT) has been introduced to the AH slurry pump range. “WRT is a series of enhancements to our AH pumps – and the technology is backward-compatible with our AH pump casings. Due to the enhanced hydraulics involved, applied in the same liner materials, we have seen significant improve- ments inwear lifeonAHpumps that havehad WRT incorporated into them,” says Jordaan. Inevitably, however, Weir Minerals also realised that the AH pump would need to be replaced by a new-generation pump, hence the releaseof theWarman ® WBHrange. “The Warman WBH slurry pump range, while still based on the original concept of replaceable liners, is a completely new design,” Jordaan continues. “The hydraulics are upgraded, along with the mechanical end and the bear- ings and a number of enhanced features have been incorporated: an adjustable front end, for example, that enables single-point

June 2018 • MechChem Africa ¦ 9

KSB Pumps for University of Pretoria laboratory KSB Pumps andValves has assisted the University of Pretoria (UP) in the construction of a large controlled-temperature test unit, which will form the backbone of ongoing research into heat transfer, fluid mechanics and thermodynamics.

A n impressive new liquid tem- perature control unit at UP allows students to plug directly into hot, moderate or chilled liquids to use on research projects and will shave approxi- mately50%off students’ overall project build- up time, thereby allowing more time to carry out actual research. In addition, it is expected to save considerable costs in future. Chairman of the School of Engineering and Head of Mechanical and Aeronautical Engineering, Professor JosuaMeyer, says the multi-millionRandprojectwaspart-fundedby theUniversity, withdonations from industrial companies such as KSB Pumps and Valves of funds, equipment and the construction of the system. About the centralised temperature-con- trolled unit, the Meyer explains that the sys- I n stark contrast to the previous pump sets at the Navachab Gold Mine, which operated a mere 4-6 weeks between breakdowns in the aggressive wear environment with resultant stoppages and production losses, tenKSBLSAslurrypumps have now been in continuous operation for nearly a year. KSBPumps andValves’ AndreasGremels says that when the mine’s management be- gan to seek alternative solutions from new suppliers; KSBwas able to convince themof the LSA-series’ technical superiority. “We have now backed up this recommendation with actual on-the-job proof. Our pumps have proven that they can work reliably and efficientlywhere others simply cannot,” says Gremels. He adds that the hard metal design and additional high-pressure glandwater system is less prone to component wear. KSB LSA pumps make use of a unique high-pressure gland water system and gland service pack- age that pressurises the stuffing-box with

non-slurry laden water to prevent particle ingress that can cause wear of components. Hard metal linings and specially designed impellers further contribute to the hard- wearing nature of the pumps. “This goes to show that specifying the right pump for a technical application is critical to the success of pumpingoperations. In the case of the Navachab Gold Mine, the additional performance gains and reliability werecomplementedbytheoutstandingwork done by the technical teams of the owners, QKR Namibia. They designed and managed theinstallationoftheentireproject,including monitoring systems, andworkedcloselywith our KSB technical team to ensure optimal performance and longevity of the pumps and the entire installation,” reports Andreas. QKRNamibiaProjectsEngineer,duPreez Calitz, confirms the success of the project. “The pumpswere selectedbased on the long termwear simulations done by KSB and the full life cycle cost analysis presented during the tender evaluation process. We have temrelies on temperaturemonitoring of flow loopswherewater is conditioned through the relevant heat pumps and chilling units at near boiling or lower temperatures, as well as at subzero glycol temperatures down to -20˚C. “The user demand within each loop is controlled using a system of pumps, variable speed drives, pressure transducers and spe- cial valves to allow up to eight experiments to plug-in simultaneously, without affecting either the flow rate, working pressure or temperature of the unit. This calls for abso- lute reliability and requires the best possible equipment to be used to avoid downtime that may impede any of the research pro- grammes,” says Danie Gouws, Technologist of the laboratory. “In the research laboratory, reliability is of the utmost importance and means that the

not looked back since then! In fact, an open inspection of the pumps recently revealed a much lowerwear rate than initiallyexpected, which has resulted in lower operating and maintenance costs as foreseenover the total lifecycle of the pumps. TheseKSBLSA slurry pumps have certainlymet and exceeded our expectations and the solid technical input and support of the companyhas been superb from the outset.” Echoing the sentiment, AKRoux, projects and asset management manager for QKR Namibia, adds that thenewpump stationhas now run more than 5 000 hours without a single breakdown. He added that the project teamplaced specific focus on the evaluation of the full life cycle cost of the operation and maintenance of the pumps during the design of the newpump station and the selection of equipment. This resulted in a pump installation that consumes 18% less power under similar op- erationconditions than thepreviously instal- lation, while themaintenance requirements over thefirst 5000hours of operationswere limited to the repacking of the glands and the checking of bearing assembly oil levels. KSB Pumps and Valves slurry pumps manager, Rob Bond, says the rural nature University cannot compromiseonqualityand, therefore, procures the best, most suitable equipment that money can buy.” Through its learned-team, the University specified five Etanorm50/32/250 pump sets with 3.0, 2.2, and 1.5 kW motors, respec- tively, selected to deliver the flow rates, pressures and other requirements. With their proven reliability and unwavering performance, Etanorm pumps were seen as

Slurry pumps push the boundaries of reliability KSB Pumps and Valves has busted the ‘slurry pumps have short lifespans’ myth with the ongoing success of its Navachab Gold Mine installation in Namibia, where ten of its LSA slurry pumps have operated for nearly a year without incident.

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⎪ Pump systems, pipes, valves and seals ⎪

Left: Professor Josua Meyer, Chairman of the School of Engineering and Head of Mechanical and Aeronautical Engineering of the University of Pretoria, with the department’s new liquid temperature control unit. Right: Etanorm pumps form the backbone of the system. The Intricate design ensures that researchers have the right temperature fluids at their disposal at any time.

safety as well as micro and power-related electronics, heat exchange tubes and clean energy studies, among others being carried out by ten staff and 30 full time students in- cluding tenPhDstudents, aswell as a number of Master’s students. KSB Pumps and Valves’ external sales representative, Dylan Mitchell, says the companywas initially approached by Ascend Consulting Engineers to obtain data on the pumps. The company later revealed that a project was being undertaken for the University and that sponsorships were be- ing sought. “In this regard we are always ready to assist educational institutions and gave the thumbs-up to the project. Wherever techni- cal assistance was required we were happy toweigh-inwith our expertise, butmust com- mend the University, consulting engineers and the contractors whoworked tirelessly to deliver a world-class installation. “As a result, we are proud to be associated with this prestigious projectwhich lends itself to assisting future engineers to change the face of tomorrow. This is another feather in the KSB cap,” says Mitchell. With the system up and running, Meyer says that the project is already proving to be a great success with numerous research projects already plugged-in. “We are thankful for the ongoing support of companies for our students, their projects and theUniversity. Considering heat transfer isafundamentalsubjectforallundergraduate engineering studies and that the University of Pretoria produces between a quarter and a third of the country’s engineers, we believe that this kind of support is essential. It can be viewed as a strategic investment in engineer- ing for all of South Africa,” he concludes. q

ideal for the pumping requirements of this complex system. PLC-controlensurethatallparametersare checked and balanced to ensure the system delivers fluid at the right temperature set points and flow conditions, 24-hours per day, regardless of the number of students using

the facility. It also ensures that ongoing and larger-scale research projects can be under- taken, including some cutting-edge research that is already being done in collaboration with other international Universities. These include valuable research concern- ing concentrated solar power (CSP), nuclear

Ten KSB LSA-series’ tailings slurry pumps at the Navachab Gold Mine in Namibia are disproving the myth that slurry pumps have short lifespans.

of this, and other mines in Namibia, makes it imperative that the pumps are manufac- tured fromthehighest qualitymaterials and manufactured to the highest international standards. Correct pump selection is also important, making it essential to work with the best technical teams available such as those of KSB Pumps and Valves. “The success of our slurry pumps in

tough Namibian conditions is important to us as it gives us leverage to introduce our slurry pumps to other mines in the region. We are already one of the top suppliers of water pumps to mines in Namibia and the addition of our ultra-reliable slurry pumps enables us to become a multi-faceted solu- tionsprovidertotheindustryinNamibiaand elsewhere in southernAfrica,” says Bond. q

June 2018 • MechChem Africa ¦ 11

Pumping systems 101: Landlords and pumping systems In this month’s Pumping system 101 column, Harry Rosen of TAS Online and 2KG Training, compares his experience of getting his landlord to refund overbilled utility expenses with the approach that needs to be taken to optimise a pumping system.

A t the beginning of every pump training session, I include a couple of slides that compare the costs of owning a vehicle with the lifecycle costs of operating a pumping system. This makes the issues easier to relate to for del- egates who either own a car or know a fair bit about the costs associated with running a vehicle. When purchasing a car, about 55% of the lifecycle cost is related to energy. This is a relatively large portion of the pie, thus we make a conscious decision to purchase a vehicle that has lower ongoing costs (fuel and maintenance), and are often willing to pay more as a result. An example of this would be opting for a diesel engine, which costs more to purchase than the petrol equivalent, but has far greater fuel consumption. Therefore the long term running costs are lower. This is a conscious decision to spendmore capital up front, in return for ensuring long-term energy savings. In the caseof apumping system, total costs over five years are completely dominated by the costs of energy. Even in its first year of use, the operating costs of a newpump amount to almost four times the purchasing cost. And

over the five-year life of the pump, energy costs amount to nearly 90% of the total cost of ownership. In spite of this fact, however, most compa- niespurchasethecheapestpumptheycanand continue to strive for the best discount, even though the operating costs are going to be far higher over the life of the pump. Why does this happen? One reason at the designor purchase stage is that the initial pur- chasecostiscoveredunderthecapitalbudget, whereas the future energy and maintenance costs fall under operating expenses. The de- sign consultants or purchasing departments are tasked with reducing costs in their area, and do not see the benefit of reduced energy or maintenance costs. Once the plant has been built or new equipment commissioned, the energy cost of running the pump is hid- den from the user, buried away in the plant’s monthly bills. However the ongoing costs of operatingour car areonly tooapparent, when we fill up at the petrol pump, or are forced to take an additional bondon our house to cover a repair bill. Which bringsme to landlords and another real world example that might help people better relate to the problems and opportuni-

ties when optimising a pumping system. We moved offices recently, one of the major reasons being the appalling lack of service fromour landlord/managing agents. After nearly 18 months of continual fights, dozens of emails back and forth, and hours and hours of wasted time, we have finally been refunded a portion of what has been incorrectly chargedover theyears, although the fight to get back all that is owed still has while to go. So what has this to do with pumping systems? Looking back, I can see that I have subconsciously taken a similar approach to investigating our billing issues as I would when optimising a pumping system. Here is an outline of the approach: Step One: sourcing and analysing the relevant data, or lack of visibility In the case of our landlords: The monthly rental bills did not have the level of detail required to check whether the charges were correct or not. It took almost a year of requesting this information before I had sufficient detail to pick up the inconsisten- cies and mistakes in their monthly billing.

R200 000 car cost

R200 000 pump cost

Miscellaneous 1%

Miscellaneous 2% Purchase 4%

Maintenance 6%

Energy 33%

Purchase 42%

Energy 88%

Maintenance insurance 24%

For a R200 000 car that consumes 12 km/ ℓ of fuel and is used to travel 32 000 km/year, the fuel cost for the first year is R32 000 and across its five- year life, fuel will account for 33% of the total costs.

On a 75 kWpump with an initial cost of R200 000 and maintenance cost of R60 000, the energy cost in the first year amounts to R770 000, while over the pump’s five year, the energy costs will account for 88% of the total lifecycle costs.

12 ¦ MechChem Africa • June 2018

⎪ Pump systems, pipes, valves and seals ⎪

This included detailed water and electricity consumption reports, as well as information about the system such as the rentable area of the office, common use charges for utili- ties, etc. Pumping systems: The biggest obstacle to improving energy efficiency isminimal instru- mentation on the pumps. Or where there are suctionanddischargepressuregaugesorflow meters installed, theseareoften inaccurateor not working. Electricity consumption figures are only broken down intomajor areas of the plant, which also includes many other non- pumpingusesof electricity. It is rarelypossible to get individual energy consumption figures for pumps. Often, the only option is to install portable instrumentation and power meters yourself and then to independently collect the data needed. Landlords: Now you have all the data at your fingertips, thenext step is prettyeasy. Identify and quantify all billing errors and start count- ing the rands and cents that should soon be coming your way. Pumping systems: This is the hard part. It requires a thoroughunderstandingof the sys- tem and the intimate workings and operation of your pumps. I have investigated well over 50 pumping systems over the last 12 years and I amstill learningnewways to saveenergy everyday.Essentially,theideaistofindwaysto reduce the losses in thepumping systems and/ ortochangetheoperatingpointsofthepumps in order make the pumps run as efficiently as possible within the operating system. Landlords: Convince the landlord of their billing errors and get them to refund these charges. In most cases the only response you will get is deathly silence, but with a bit of perseverance (and possibly the threat of legal action thrown in), you should finally be seeing the fruits of your labour in terms of a substantial refund on your rental bill. Step Three: Implement recommendations Step Two: Identify cost-saving opportunities:

Suction and discharge pressure gauges and flow meters are essential in order to determine accurate energy consumption figures for pumps.

Pumping systems: There is no point go- ing to all the time and effort to identify and quantify these opportunities if they never get implemented. Start with the low hanging fruit – simple, inexpensive changes to the operation of the pumps or system that lead to substantial savings inenergy. These savings can then be used to fund the longer term and more expensive capital projects. Inboth cases we will need the buy-in and active support of bothmanagement and shopfloor personnel in ordertoimplementthesechanges,andensure the system doesn’t slip back to its inefficient state over time. In our consulting engineering business, rent, water, electricity, etc make up a sub- stantial portion of our operating costs and, in the end, all the time and effort was worth it. To datewe have been refunded over R80000 in incorrect billing, with another R125 000

still in the pipeline. This, for a moderate size office in a large commercial office block, is a substantial savings in operating cost, andwill ultimately help keep us in business and pos- siblyeven inflateour profits for theyear.Most people give up in frustration and abandon the project long before achieving any monetary reward – something the landlords out there are counting on. So when comparing landlords and pump- ing systems, the ultimate goal is the same – to reduce unnecessary costs and improve the profitability of our businesses. For clientswithpumping systems, electric- ity and maintenance costs are one of the big- gest components of ongoing operating costs. Saving money on your pumping system will go a long way to making your business more profitable, ensuring you are around for many years to come. q

Even in its first year of use, the operating costs of a new pump amount to almost four times the purchasing cost. And over the five-year life of the pump, energy costs amount to nearly 90% of the total cost of ownership.

June 2018 • MechChem Africa ¦ 13