MechChem Africa March 2018
Mech Chem MARCH 2018 AFRICA
Work with the expert Manufacturer of PTFE components South African company supplies to the world market Valve parts for maximum reliability
This month: Five ways solar PV can optimise industrial electricity use
Multiflo pontoon and walkway range for pit dewatering
Promoting transformation in the diamond industry
Storage and disposal requirements for generators of used oil
8
19
24
34
Pump systems, pipes, valves and seals 8 Multiflo pontoon and walkway range for pit dewatering Howard Jones, business development manager for dewatering at Weir Minerals Africa, presents his company’s expanded range of Multiflo ® pontoons and walkways for dewatering mines. 10 Pump systems 101: Training pump-system experts for a measured ROI 13 Pump maintenance is key to efficiency 14 Mines urged to dredge ponds before rains arrive Localisation, manufacturing, production and food processing 16 Promoting transformation in the diamond industry In order to facilitate the growth and transformation of the South African diamond industry, De Beers has embarked on an Enterprise Development Project for Diamond Beneficiators. MechChem Africa talks to Frank Auger. 18 Award-winning mobile bending cell 19 Robor’s world-class pipe mill installed in Elandsfontein Power generation, sustainable energy and energy management 21 First-of-its-kind distributed generation platform developed Cummins Inc and NRG Energy (Next Renewable Generation) of the US have announced a strategic commercial partnership to deploy a resilient, cleaner and more cost-effective distributed generation platform for commercial and industrial customers. 23 WTA oil lab helps avoid transformer failure Petrochemical, oil and gas 24 Skyriders’ five-year contract at petrochemical producer From work at tank farms to power station boiler inspection, Skyriders’ five-year contract at a major petrochemical producer in SouthAfrica has progressed in leaps and bounds indicating the total value-add that a specialist service provider can offer to its customers. 26 A well-trained workforce boosts profits Environmental, waste management and cleaning technologies 28 Storage and disposal requirements for generators of used oil The ROSE Foundation has been championing the responsible collection and removal of used oil for proper recycling since 1994. CEO, Bubele, offers some practical advice. 28 Shortcuts add to SA’s environmental challenges Innovative engineering 34 Five ways solar PV can optimise industrial electricity use DominicWills of SOLA Future Energy outlines how offgrid rooftop solar PV installations can optimise energy use in commercial and industrial buildings. REGULARS 2 Comment: Quality artisan training and the QCTO system 4 On the cover: Proudly SA PTFE manufacturer supplies the world MechChem Africa visits the PTFE facilities of Trident Plastics and talks to operations manager, Louis Botha about the manufacturing process and the company’s niche offering. 6 SAIChE iCHEMe News: Stealing the future: Is SA’s response to climate change appropriate? 30 Product and industry news 36 Back page: New technology uses gravity to store green energy
P U B L I C A T I O N S CR O WN
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: Karen Smith 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
2015CROWN LOGO february.indd 1
Transparency You Can See Average circulation October-December 2017: 4 668
Printed by: Tandym Print, Cape Town
Front cover: Trident Plastics Jet Park, Boksburg +27 11 824 0696 Louis.botha@trident-plastics.co.za
March 2018 • MechChem Africa ¦ 1
Peter Middleton Quality artisan training and the QCTO system I am one of those who believe that practical skills have been neglected and undervalued for far too long, not only in South Africa but also across the globe.
full-blown apprenticeship …which will combine tech- nical education and simulated practical training at the SAIWwith authenticwork experience in a fabricator’s workshop,” says Nell. In order to link training more tightly to indus- trial needs, the biggest number of hours, 2 200, is reserved for workplace modules (WMs), which are interspersed with training-school-based knowledge (KMs) andpractical modules (PMs).Most importantly, however, the practical modules are scheduled by the apprentice’s employer, via a memorandum of under- standing with the training provider, so that every apprentice can be gainfully employed immediately on completing each four- to six-week module at the welding school. In this way, real work experience and formal training become interactive, making training more relevant to the trainee and more useful to the employer. “Right from the start, companies that employ ap- prentices benefit via very cost-effective labour rates with additional benefits including: SETA training grants; SARSTax incentives; B-BBEE score-cardpoints and social responsibility credentials,” says Nell. Nell has done some cost calculations to highlight the real and opportunity costs of training an artisan. Given a total cost for the three year programme of around R510 000 per artisan, of which nearly a third is wages, Nell calculates that the SETA Grant (R165 000), the SARS Allowance (R40 000) and the SARS Employer Training Initiative (R18 000) reduce this total to R287 000. The SAIW Foundation is cur- rently also offering a further R75 000 incentive per apprentice, which reduces the real cost to R212 000. But Nell argues further that the apprentice’s pro- ductivitywhile training not onlymakes this cost disap- pear, but it also reflects as profit from the investment. “If,forthelast18monthsoftheprogramme,weassume that an apprentice is 65%productive but is being paid 32% of his full salary, the employer will be saving the equivalent of R327 000 compared to an artisan that is 100%productive,” arguesNell. This turns a cost, albeit a justifiable one, into a R115 000 benefit. SAIW, through the SAIW Foundation, will commit R1.5-million over two years to subsidise 20 welding apprentices on its QCTO pilot training programme. But it needs buy-in from industry partners willing to recruit apprentices and put them to work on their factory floors. It is sure to be worthwhile, in the short term and the long term. And it may also result in a restora- tion of the deserved status in society of people with practical skills. q
Artisans in industry, althoughhighly trained, skilled and essential to the economy, are seldom ‘hailed’ as pillars of society. Neither do they always enjoy em- ployment security, because the project work they do is cyclical and very sensitive to swings in the economy. Across the world, teaching and nursing are seen as more respectable than plumbing or welding, but are they better paid? I don’t think so. Changing young people’s attitudes towards skills- based technical careers or occupational qualifications remains a huge problem in South Africa. This must begin in schools at a young age, with learners engag- ing in more practical and technical activities such as those specified in the Revised National Curriculum Statements grades R-9 for South African Schools. Here though, it is the quality of the teacher/pupil in- teraction that needs attention so that young learners emerge from the system with a positive and realistic experienceofpracticalwork.Theboring,irrelevantand theoretical technology classroomneeds to become an exciting, meaningful and practical one. For school leavers, however, it is the prospect of real, well-paid jobs attached to career paths and high-status qualifications that is likely to attract them. In the past, artisan training was always directly associated with on-the-job training, with every ap- prentice being allocated to the care and tutorage of a skilled and experienced journeyman, who would already have an official apprenticeship qualification in his trade or craft from a relevant guild – and these journeyman certainly had status. The direct link between a skilled artisan and an apprentice has long been lost, and, in South Africa, apprenticeship programmes themselves were in seri- ous decline following the tepid reception and widely varying quality of unit standards-based Learnership programmes. But we now see a very welcome attempt to revit- alise andmodernise apprenticeships under theQCTO (Quality Council for Trades and Occupations). The SouthernAfrican InstituteofWelding (SAIW), through its training specialist, Etienne Nell, has been part of developingnewthree-yearQCTOartisan trainingpro- grammes, which now include a new SAQA-registered apprenticeship for Welders. Called a dual system apprenticeship, the key prin- cipal, according to Nell is that industry needs to take charge by appointing its own apprentices. This is “a
MechChem Africa is endorsed by:
2 ¦ MechChem Africa • March 2018
Proudly SA PTFE manufacturer supplies the world
MechChem Africa visits the PTFE (polytetrafluorethylene) facilities of Trident Plastics and talks to operations manager, Louis Botha about the manufacturing process and the company’s niche offering.
T rident Plastics is a specialised manufacturer of PTFE products, which are widely used for industrial valve components and other sealing solutions. “We are a Proudly South African company that produces all of our products here in our Boksburg facility and we have been a PTFE specialist in this country since 1998,” says Botha. After having traded in the local market as Hardomid Plastics for many years, Trident Plastics was recently bought out by one of its principal customers and immediately started to expand itsmarket to also includeEuropean OEMs. “Various industries and markets have been supplied by Trident Plastics, but the company’s strongest footprint is in the valve industry where Trident’s products are used to seal industrial valves internally and to at- mosphere according to highest international standards,” says Botha. Trident Plastics supplies both semi-fin- ished components and completely machined PTFEparts. Latest state-of-the-artmachinery is used to manufacture PTFE billets as well as finished components from the smallest micro parts to big and heavy PTFE liners. Recent investments into new production capabilities enable the company to meet
highest international quality demands and to supply the market in very
short lead times. AccordingtoMD, Erich Ermel: “Highest quality supplied with short lead times is our strength and what we strive to constantly improve.” The company’s new Boksburg prem- ises were acquired in order to cope with increasing demand from the market. “Our newpremises allowus to further improve our workflowand, additionally, we have installed fully air conditioned production facilities ac- cording to latest state-of-the-art technology, which sets a new benchmark in the PTFE industry. Trident Plastics keeps a wide range andhighvolumes of PTFEpowders in stock to keep thedelivery reliabilityhighand tobe less dependent on the volatile PTFE rawmaterial market,” says Botha. “The international market demandsmore from a supplier than products. Customers expect us to develop components according to their very specific needs,” he adds. “This is one reason why the company has set up its own design and in-house laboratory
PTFE bellows with metallic flanges to compensate for axial-, radial- and angular displacements of pipelines.
facilities where products can be developed and tested according to exact specified requirements.” Describing the need for PTFE in the valve industry, he explains that PTFE is an ideal contact seal material because of its low fric- tion coefficient, good sealing capabilities and excellent chemical resistance. “Ball valves, butterfly valves, plug valves, safety valves andmany other types of industrial valves use mainly PTFE components for internal and ex- ternalsealsandbothvalvemanufacturersand valve repair companies use our PTFEparts to achieve reliable tightness thatwithstands the chemically corrosive media used in chemical processes,” he explains. Parts manufactured start from simple sealing rings up to large and complicated components where excellent tightness and safety ismandatory. Trident Plastics supplies internationallyrenownedvalveOEMsinlarge quantities “but we also supply small and local valve refurbishment companies who have very specific demands”. On a tour of the Boksburg facility, Botha starts at the rawmaterial store, where sealed boxes of rawmaterials imported fromEurope are stored. “We import different PTFE pow- dermixes. Thewhite PTFE is pure and known as virgin PTFE. It has the best chemical resis- tance in the range,” he says, warning that the powders shouldnever be touchedas even the smallest amount of contamination can impact the material’s properties. As well as virgin PTFE, glass-, carbon-, graphite-, bronze-filled and other powders are also imported, depending on prevailing client needs. “Carbon- and graphite-filled PTFE offer a longer wear life under wet or dry conditions and are suitable for use as high
Ball valve seats and packings in various materials for different applications.
4 ¦ MechChem Africa • March 2018
⎪ Cover story ⎪
temperature bearing materials, particularly when a load bearing capability is required,” Botha explains, adding that glass-fibre-filled PTFE,withglasspercentagesvaryingfrombe- tween5 to40%, offers improvedcompression andwear properties. “Bronze-filled PTFE has better hardness and size stability and is used for tubes and seals in the hydraulics industry and for compressor wear, piston and bearing rings,” Botha informs MechChem Africa . Using one of the hundreds of moulds designed, collected and manufactured by Trident Plastics over the years, powders are then pressed into near-product billet sizes or component blanks. “After inserting the correct mould, the powder is weighed to the exact quantity required and then poured into the mould. It is then cold pressed into billet shapes of anywhere between 20 and 520 mm in diameter,” Botha explains, add- ing that the compression ratio by volume is about or 3:1 under pressures of between 1.5 and 3.0 MPa. “When removed from the press, the ma- terial is un-fused and very brittle. It is then transferred intooneof our ovens for sintering at between360and370°Cand, depending on the size and wall thickness, it takes up to 18 hours to fully ‘cure’ a billet – and some large blanks take 56 hours to cure,” Botha tells MechChem Africa . Botha points at a big billet with a hollow core destined for use in making PTFE skived tape. “This is a skive billet that will be placed on a machine with a shaving knife to produce the ultra-thin skived tape,” he explains. Sintered billets are a key product for Trident Plastics, for use by downstreamvalve and other product manufacturers, which machine the PTFE components they need in their own workshops. “But we also have our ownmachine shop formanufacturing custom designed components, our niche being valve seals and seats,” Botha says, taking us into a machine shop next door where components are being profiled, chamfered, threaded and sized. “We often have to use sophisticated jigs to hold the PTFE blanks for the likes of ball valves. And another factor complicating ma- chining processes for PTFE is temperature. The material is more flexible when hot, so re- sponds differently tomachining, sooneneeds tobe very aware of temperatures –one of the reasons for the air conditioning,” he notes. “While theprocess is simple inprinciple, there aremany subtle complexities that can trip up inexperienced people,” he adds. On the waste side, Botha says that the company strives to keep the blank sizes as near to the finished size as possible to reduce waste, both for cost saving and for environ- mental purposes. “Whilewe don’tmanufacture or assemble
PTFE liners for Butterfly valves.
Machining of PTFE components on multi-axis CNC machines.
valves, some customerswill sendus a stripped down or re-machined ball or butterfly valve for us to take accurate measurements. We will then manufacture a billet and machine a seal to suit the new size. And this service is available to any valve manufacturer and any valve brand,” he assures. Describing its properties, Botha says that PTFE is a thermoplastic, but due to its high viscosity,itcannotbeprocessedusingconven- tional polymer processing techniques. “PTFE has to be first processed cold during shaping/ pressingoperations, followedbyhot sintering to fuse the particles. It can also be welded, though, should a particularly large billet or component be needed.
“Generally, PTFE is a tough, flexible, non- resilient material of average tensile strength but with great thermal properties, a very low friction coefficient andexcellent resistance to chemicals,” he says. “The list of applications of PTFE is almost endless. Its excellent proper- ties lead to its use in numerous everyday applications, from the plate support rings in almost every microwave oven, to pots and pans and even clothing,” he says. “In the industrial spaceTrident Plastics has now become a global specialist in the design and manufacturing of PTFE solutions for parts used in chemical, petrochemical, food and beverage applications, as well as a host ofmachinery seats and seals,” he concludes. q
March 2018 • MechChem Africa ¦ 5
Stealing the future: Is South Africa’s response to climate
Considering the drought in theWestern Cape, Rosalind dos Santos, MSc Eng (Met), BSc Eng (Chem), CEM, evaluates South Africa’s response to climate change.
I s South Africa’s response to reducing greenhouse gas (GHG) emissions jeop- ardising the future of young South Afri- cans? Worldwide, civil society has taken greater action against governments that are perceived tonot be serving their constituents. There is greater social accountability, and in many parts of the world climate change and the link to anthropogenic GHG emissions is clearlyunderstoodanda reduction innational GHG emissions is promoted. In South Africa, however, we have yet to see the same level of social accountability that is apparent in other countries. Populationpyramids producedbyStatsSA, discussing South Africa’s demographic divi- dend, showmost of our population under the age of 35. This young population will feel the first real effects of climate change that result from our inaction. Climate change risk The clear lack of priority given to environ- mental and climate-related risks in South Africa is evident when comparing the World Economic Forum (WEF) Global Risk Report and the Institute of Risk Management South Africa (IRMSA) Risk Report. In the WEF Global RiskReport, ExtremeWeather Events, Natural Disasters and Failure of Climate Change Mitigation and Adaptation risks are consistentlyhigh ranking from2015onwards, making up three of the top five risks in terms of likelihood and impact. On the other hand, the risk of Droughts in Sub-Saharan Africa is the only environmental risk identified in the IRMSA Risk Report. This risk is present in the mid-2016 and 2017 risks, ranking 4 th in the top five risks in terms of likelihood, 1 st in terms of impact in mid-2016 and 3 rd in terms of impact in 2017. In all other years, environ-
mental and climate-related risks are absent from the IRMSA Risk Report. In the latest Intergovernmental Panel on Climate Change Assessment Report 5, the climate change affected areas highlighted for Southern Africa are terrestrial ecosystems, livelihoods, healthand/or economics. Further, there is high confidence that those living in poverty will feel the impacts of climate change, exacerbating other stressors in their lives. This is particularly relevant in South Africa where 56.8% of people live in poverty. Thus, there appears to be environmental, social and economic motivations to act to reduce GHG emissions. The risk reports show that although cli- mate change may be top of mind globally, it is not for South Africa. South Africa’s energy supply and associated economic activity is heavily reliant on its large coal resources. Focusingon reducingGHGemissions inSouth Africa would require a move away from coal, impacting our energy supply and economic activity. As such, there seems to be a financial incentive for SouthAfrica to exploit fossil fuel resources and extend the timeline before climate change is dealt with. An exception to this is renewable power generation, with the cost of solar photovol- taic (PV) and wind energy below the cost of non-renewable energy. Nonetheless, the electricity generation grid remains predomi- nantly coal-fired power generation at 90%of Eskom’s power generation. Whilst South Africa is a developing coun- try, our per capita GHG emissions are higher than the global average (6.249 t of CO 2 e versus 4.936) and much higher than many other developing countries. As mentioned, this is largely due to our dependency on coal for energy, with energy being responsible
for 78.7% of our latest country-level carbon footprint in 2010 (excluding forestry and other land use carbon sinks). Arewe already seeing the result of climate change bearing inmind that a singleweather event does not demonstrate climate change? Water risks, both in terms of availability and quality, came to the fore in 2017 andwill con- tinue to be a key and high-ranking risk over the five-year horizon in many parts of South Africa. Two largemunicipalities are currently declared as disaster areas due to extreme water shortages, and this is one of the key climate change predictions: that Africa will becomedryer.With lower thanworldaverage rainfall, SouthAfrica is alreadywater stressed and the key link of water in the energy sec- tor (for steam production to turn turbines, to generate electricity or in the refining of oil for liquid fuels) should not be overlooked in terms of economic, environmental and social impact. Possible solutions The National Climate Change Response Strategy proposes using emission tra- jectory plans, sector emission reduction outcomes, carbon budgets, economic in- struments and better data and information gathering, but was last published in 2011. Further, the IntendedNationallyDetermined Contribution presented by the SouthAfrican government in Paris was vague in terms of South Africa’s binding commitments. Now in the Nationally Determined Contribution, the emissions targets arewithin the range of 398 to 614 Mt CO 2 e, which is quite a broad target and planned emission reductions are only envisaged from 2020. In addition, our emissions from our last GHG inventory With rainfall lower than the world average, already water stressed South Africa is at risk of being unprepared for the severe water shortages to come.
Rosalind dos Santos Rosalind dos Santos is a qualified chemical engineer and cur- rentlyworks as theHead ofOperational Sustainability inGroup Real EstateServices at Liberty. She is a sustainabilityprofessional with ten years of experience in carbon and climate change-related projects, strategydevelopment andexecution, energyefficiency project oversight andmanagement andwater project plan- ning and development. She is also a founding member of SANEA Young Energy Leadership Forum. The views expressed in this article are her own, in- formedbyexperience,literaturereviewandotherexpert opinion pieces. Please feel free to write to the editor about your thoughts on climate change. q
6 ¦ MechChem Africa • March 2018
⎪ SAIChE IChemE news ⎪
change appropriate?
18 subjects, the University of Pretoria with 15, UKZN with eight, the University of Johannesburg with four and Rhodes University with two subjects. Five of South Africa’s universities per- form strongly in developmental studies, with the subject being the highest-ranked subject at UCT, Stellenbosch, UJ and UKZN. At Wits, the subject is the second strongest subject, after mining and min- eral engineering, whereWits ranks as the 15 th best university in the world for that subject. Wits is also the only university in South Africa ranked for mathematics. The Universities of Pretoria and KwaZulu-Natal, meanwhile, are also the best universities in the country for theo- logical and religious studies, whileRhodes makes its mark in communication and media studies. Source: businesstech.co.za As chemical and metallurgical engineers, thereisagreatopportunitytodesignefficient, environmentally responsible plant, processes and production. We should also be using our knowledge and experience to create aware- ness of these issues in our daily interactions. Over engineering that often comes with excessive energy use should be regularly questioned and challenged. Opportunities to meet design and client briefs in more long term and future forward ways – considering operating costs, emissions and resource use – should be taken wherever possible. Small changes to designs tominimise energy, water and waste will have a large impact over the operating lifetime of the plants andprocesses that we design.We should also look to nature for our contribution to the global problem may be questionable. There may also be more effective market solutions. Renewable energy generation technologies, cost-effective battery technol- ogy and electric vehicles may give forward thinking governments the ability to manage and reduce GHG emissions. The ability to respond in an agile way to these technology disruptors will be an important component for South African climate change mitigation and adaptation. An important positive item to note here, however, is the launch of the South African Risk and Vulnerability Atlas and the accom- panying African lead submission for climate modelling into Assessment Report 6. This speaks volumes for our National Science and Technology; and will hopefully translate into clear and effective climate policy that is not overly detrimental to the economy.
and biomimicry and the many advances that are coming from this field that allow us to make so much more, from less. The scale and impact of climate change is not fullyunderstoodbyall SouthAfricans, and thus there is a potential risk for the country of being unprepared for changed weather patterns and climate.While the SouthAfrican government has some policies and instru- ments in place to mitigate climate change effectsandreduceemissions,wemaybesteal- ing the future fromour youthful populationby failing to act more decisively. Similarly to how South Africans are only now feeling the consequences of the poor planning for the water shortages, so too will the future generations feel the consequences if we do not act now to mitigate the risk of climate change. q
For a list of references see online article www.mechchemafricamagazine. co.za
SAIChE IChemE
are already within the range and it seems likelywe couldmake the 2025 to 2030 target possible without any additional emissions mitigation. The latest development in terms of eco- nomicinstrumentsistheSouthAfricancarbon tax bill that will probably soon be passed. However, whether this is an environmental levy or an instrument to further close the tax gap – estimated at R90-billion for this fiscus – is still in question. Thus, while there are several frameworks that have been conceived and can be rolled out, whether these are enoughand significant
SAIChE Board members: President: C Sheridan Imm. Past President D van Vuuren Honorary Treasurer L van Dyk + Vice President: Honorary Secretary: EMObwaka Vice President: D Lokhat Council member: JJ Scholtz Council member: AB Hlatshwayo Council member: K Harding Council Member: M Low Council member: BK Ferreira Council Member: HMazema Council Member: MChetty Council Member: A de Bondt Council Member: MMabaso Council Member NN Coni Member (co-opted): MD Heydenrych Chair Gauteng: C Sandrock Chair KZN: D Lokhat Chair Western Cape: HMazema Contact details SAIChE PO Box 2125, North Riding, 2162 South Africa
SA universities rank among the best The latest QS World University Rankings has listed all the subjects that South Africa’s top universities excel at in 2018 – ranking them among the top 500 courses in the world.
The report covers 42 subjects in arts and humanities; engineering and technol- ogy; life sciences and medicine; natural sciences; and social sciences. South African universities stand out for their expertise indevelopment studies, QS said, while South Africa’s top-ranked university – the University of Cape Town – ranked within the top 100 globally in 11 subjects. Overall, UCT has 35 subjects ranked within the top 500 universities in the world (all within the top 350), while the University of the Witwatersrand has 21 subjects within the top 500. This is fol- lowed by Stellenbosch University with
Tel: +27 11 704 5915 Fax: +27 86 672 9430 email: saiche@mweb.co.za saiche@icheme.org website: www.saiche.co.za
March 2018 • MechChem Africa ¦ 7
An expanded range of Multiflo ® pontoons and walkways from Weir Minerals is available in Africa and Middle Eastern markets, improving the operating efficiency of dewatering systems and increasing flexibility for mines that advance during the mining process. Howard Jones, business development manager for dewatering at Weir Minerals Africa presents the range and its advantages. Multiflo pontoon and walkway range for pit dewatering
A ccording to Howard Jones, Weir Minerals’ business development manager for dewatering in Africa and theMiddle East, theWeirMin- erals range has evolved out of site-specific requirements over the last seven years. “We have achieved considerable success with thesemining solutions in regions such as Canada andAustralia, andwe have been able to evolve these designs to suit the climatic conditions in our markets,” says Jones. “The growing demand for these products has also seen Weir Minerals Africa apply its capabil- ity to the of design specialised, custom-built pontoons.” He notes that these innovations have allowed mining customers to maintain opti- mal suction conditions during the pumping process, while alleviating the need for costly civil works and static pump stations. “The benefits of mounting equipment on a floating structure play a major role in our global drive to reduce the total cost of own-
ership (TCO) for mines and other industries,” Jones says. “Our commitment to optimise our customers’ processes is always taken into consideration in order to support their operations and profitability.” Thesefloating pump stations are designed to accommodate the whole Weir Minerals product range, including Warman ® submers- ible pumps, end suction centrifugal pumps, Multiflo ® horizontal split case pumps and Floway ® vertical turbine pumps. “While most of these pumps are electri- cally driven, we also have a range of diesel- driven pump sets mounted on pontoons with integral fuel tanks. This allows for extended operating hours,” he explains. He highlights the Multiflo ® MF 420EX pump as amarket leader in high capacity, high head and heavy-duty mine dewatering appli- cations. This, he says, it due to its extremely robust structure, materials of construction and auto vacuum-primed, diesel-driven characteristics.
“These pumps can survive under the toughest operating conditions and in multi- stage applications that function optimally in the world’s open pit mines,” he says. Multiflo pontoon-mounted pumping sta- tions are often used in conjunctionwith skid- mounted pump sets on haul roads, allowing for series pumping in deep pits. “We do, however, also have a range of products that allows us to achieveheads of up to 130 metres with a single stage centrifugal pump,” says Jones. “One of the challenges is accessing pontoons. This is overcome by the design and installation of either fixed or floating walkways, which we custom design to accommodate the varying water levels.” All Weir Minerals’ equipment is built with safety as a priority and in Africa the equip- ment is designed in compliance with the SouthAfricannational standardSANS10162, enabling the structures to withstand wind loads of up to 150 km/hour as well as point loads of 150 kg/m 2 .
Jones emphasises that anchoring systems – along with retractable walkway designs – have become an integral part of the company’s offering to allow safe operation and easy access to pumps, either dur- ing general operation or for major maintenance interventions. “These walkways average about 20 m in length, although we have recently supplied a structure that comprises 180 m of fixed walkways and 60 m of floating walkways. A pontoon at the end of the walk- ways accommodates three electri- cally driven pumps, all of which are mounted at 30° into the water to facilitate consistent priming,” he says. “This method of priming eliminates the need for expensive and sometimes unreliable priming systems.” To allow for convenient access for inspection andmaintenance, the piping and electrical supply cable systems are carefully considered when calculating loads on the walk-
A custom-built pontoon and walkway housing a Warman DWU pump and incorporating Linatex hose.
8 ¦ MechChem Africa • March 2018
⎪ Pump systems, pipes, valves and seals ⎪
ways. LED lighting can also be supplied for safety reasons for operatorswhomust access the equipment in 24-hour operations. “The quality and effectiveness of these products demonstrates the high level of in-house design and structural capabilities that Weir Minerals has to offer,” Jones says. “These customised solutions alsoconsider the environmental and social responsibilities that customers need to fulfil within the regions in which they operate.” For instance, the use of pontoons in lined ponds has become preferable to many cus- tomers, as they minimise the possibility of damaging the pond lining, which could result in pollutants leaching into the groundwater system and becoming an environmental hazard. “Our pontoon designs are generally ap- plicable to non-aggressive water conditions,” says Jones, “but we can accommodate the more demanding environments where pH levels are as low as 2.5. We do this by using specialmaterials and coatings topreserve the pontoon and pump structures.” The standardfloats usedbyWeirMinerals are constructed from rotary moulded low- density polyethylene (LDPE) and are filled with closed cell polyurethane to ensure
A Multiflo ® 420EX diesel-driven pump set on a pontoon. The Multiflo MF 420EX pump is a market leader in high capacity, high head and heavy-duty mine dewatering applications.
andtheunitscanbemovedfromplacetoplace with a bulldozer.” Jones concludes that the overall benefit of barge-mounted pumping solutions is to ensure the safe and optimal dewatering of open pit mines, leading to more profitable operations for customers. q
long-term buoyancy. This also eliminates the possibility of these floats filling with water, which could result in failure. “Wecanalsomanufactureheavydutypon- toons with steel floats to accommodate their relocation within the pit,” he says. “These are designedespeciallyforthesetoughconditions
Weir Minerals launches Multiflo ® RF dewatering pump Weir Minerals has expanded its extensive dewatering solutions portfolio with the global launchof theMultiflo ® RFdewatering pump unit. The new Multiflo RF range sets the benchmark for dewatering pump units, expertlyengineeredinacompactpackageto offer customers a light andflexible solution. The Multiflo RF unit was developed fol- lowingspecificcustomerrequestsforamore compact dewatering pump that couldmove aroundsitewitheasewhile still retaining the same performance, reliability and robust build of our other units. The rangehasbeendeveloped tooperate effectively in a variety of harsh environ- ments and applications, such as mining, quarrying, and water transfer. The small framefootprintallowsforeaseofmovement around the site, while the dirty water capa- bility sets the pump above the competition. The new RF range includes seven new units, each designed to maximise efficiency no matter the application, with the same world class Weir Minerals aftersales ser- vice and support customers expect. The unit provides a wide range of standard inclusions and a comprehensive selectionof optional features to suit customers’ dewater- ing needs. The Multiflo RF Weir Minerals offers an extensive range of mine and process dewatering products, includingdewateringpumps,hydrocyclones, dewatering screens, specialty hose, tailored pontoons and barges. The teamof dewater- ing experts provide operators with a wide range of solutions for their dewatering system in applications all over the world, drawing on their extensive engineering and application expertise. q riety of dewatering solutions for customers, and the newMultiflo RF units complement the overall dewatering offering.
The key to the compact design is the use of close-coupled pumps, which provide the added benefit of accurate pump alignment. The Multiflo RF pump is also designed with built-in skid runners and a bolt-on dozer push-bar option tooffer customers versatil- ity of operating configurations. With a global reputation as a premium supplier of dewatering solutions, built over 40 years, Weir Minerals has moved to the next stage in the evolution of its dewater- ing pumps. The new diesel-driven Multiflo RF pump presents a unit that incorporates the convenience of an auto vacuumpriming system with an inbuilt skid and a compact design.
The benchmark Multiflo ® RF range is a compact package offering customers a light and flexible solution.
range i s t he next generation of dewatering pump units, and d emo n s t r a t e s
the organisation’s renowned attention to detail and focus on delivering a product that is powerful and efficient. Weir Minerals’ dewateringportfoliocovers ava-
March 2018 • MechChem Africa ¦ 9
UNIDO Pump expert Harry Rosen has begun to incorporate UNIDO’s knowledge transfer approach into TAS Online and 2KG pump training courses in South Africa. He talks to MechChem Africa about incorporating practical site-based energy efficiency projects into training so as to create onsite ‘junior’ pump experts. Training pump-system experts for a measured ROI
T AS Online and 2KG Training have been offering pump operation and maintenance courses for plant op- erators, managers, engineers, pump operators and maintenance personnel in process environments for many years. “Our courses apply to the water and wastewater industries, mine dewatering, sugar, pulp and paper and the chemical process industries anddeal with clear liquids fromwater to fuels all the way through to viscous liquids such as bauxite, ash slurries from power stations as well as mill-circuit slurries on mines and the waste slimes being pumped onto the dumps,” begins Rosen. “Traditional training courses always in- clude theory and practice, but they often lack a clear focus as towhat the traineesneed tobe able to do by the end of the course,” he says. “Ideally, training needs to be able to prove a candidate’s competence rather than simply issuing a certificate of attendance. In order to do that, oneneeds tobe able to combine theo- retical coursematerialwith real opportunities for candidates to implement what they have learned in a practical way. And this needs to
bedirectly relevant to theday-to-dayneedsof the plant fromwhich each candidate comes,” Rosen believes. “So, dependingon the industry, weas train- ers need to find a specific practical project to enable trainees toapplyknowledgeandprove competence,” he says. A recently completed2KG training course delivered by Harry Rosen in Secunda has achieved just that. “This training course culminated in an energy efficiency project to reduce the amount of energybeing consumed by the plant’s pumping systems and, as an ultimate measure, to reduce the amount of steamconsumedbytheplant,”Rosenexplains. The Sasol Secunda plant has established plant-wide efficiency targets across its energy-saving projects, which are linked to incentives for all Sasol personnel. Through his experience as a global UNIDO Pump ex- pert, Harry Rosen has been able to use these incentives tobringanewfocus to2KG’sPump Training courses. TheUNIDOenergy efficiency programme promotes sustainable energy savings though a combination of onsite expert training fol-
lowed by implementing improvements to the plant: this while continuously transfer- ring skills to the companies involved so that efficient operation can be sustained. “Expert trainingempowers plant personnel to identify energy savings opportunities and optimise their pumping systems, at the same time fixing site-based problems affecting plant reliability. A major focus is evaluating pump performance and putting in place measures to track and monitor ongoing energy and operational performance,” Rosen says. “After making recommendations, we teach local people how to implement these changes and operate their pumps at the best possible efficiency,” he says, adding that over the years hehas presentednumerousUNIDO knowledge-transfer-based expert training courses in South Africa, as well as further afield in Indonesia, Thailand, Philippines, Malaysia and Russia. Thisapproachisnowbeingintroducedinto 2KG training courses. “During the Secunda Pumps training course, we set as the practical project the identification of opportunities to save additional energy so as to contribute to meeting the plant’s savings targets. “Pumps offer a significant opportunity to save electrical energy on most plants. Some 15 to20%of the energy consumedby electric motors is attributed to pumping, so massive savings opportunities can be identified,” Rosen says. TheSecunda training followeda successful auditing and improvement project at Sasol’s Phenol Solvent plant, where TAS Online was able to immediately implement R2.5-million per year in savings, with a further R8- to R10-millionper year thatwill be realisedonce other measures are implemented. “This proof-of-concept project success- fully convinced plant managers that en- ergy savingswere readily available fromtheir pumping systems. The Phenol Solvent plant pumps gas liquor at temperatures ranging between 80 and 140 °C and was designed some 40 years ago to use a single pump with a second backup on standby. Over the years production rates have increasedand theplant began tousebothpumps inparallel toachieve higher flow rates.
Pump graphs showing the advantage of running a single pump, compared to two pumps in parallel. The pump is 20% more efficient in single pump mode, and its reliability will be dramatically improved.
10 ¦ MechChem Africa • March 2018
⎪ Pump systems, pipes, valves and seals ⎪
“Anyone who has attended a 2KG pump- ing course knows that running two pumps in a system designed for only one causes the friction head to increase and both pumps run at lower flow, which puts the operating point far to the left of the pump curve. Not only did this result in wasting 43% of the energy used by themotors, but the reliability of the pumps is also substantially reduced.” The solution? “Making changes to the system and flow control valve to allow a single pump to be operated on its own. In one system, a 27% efficiency improve- ment was achieved, saving in the region of 600 000 kWh/year. Along with another two systems in the same plant that reduced energy consumption by 32%, total savings of R2.5‑million per year accrued. “This case study formed a central part of the theoretical aspect of the Secunda Pump training course, exemplifying the real value of adopting the practical audit-based approach,” Rosen informs MechChem Africa . Efficiency saving andopportunities identi- fied during training also have a massive addi- tional benefit: better pump efficiency always leads to better pump reliability. Rosenquotes Sasol’s Jurgens Louw, senior engineer – energy efficiency: “Every oppor- tunity identified has the potential to turn into a multi-million rand saving opportunity. Also, the meantime between failure (MTBF) of critical equipment is improved along with reliability and parts availability. “Using a set of measurable KPIs estab- lished at the plant, pump operators and maintenance staff attending the course are enabled to easily indentify opportunities for savings. Running a pump close to its best ef- ficiency typically improves the pumps MTBF from as little as three months to over two years – and pump operators fromthe Sulphur andTar,GasificationandWaterandAshplants can all benefit,” Rosen notes. 2KG courses deliberately cater for the broad spectrum of people engaged in pump systems: process engineers; system design- ers; area managers; fitters; artisans; and maintenance personnel. “It doesn’t help to remove a pump when it breaks, fix it, and put it back into servicewhere itwillmost likely fail again. Inmany cases the problems are caused by the way the pumps are being used in the system. By targeting everyone’s understand- ing of the causes of failure, a fitter who sees a high pressure gauge reading can alert the process engineer to a potential problem. And following a failure, they will ensure that the restored pump is being run at its optimal duty point toavoida repeat occurrence. Long term, all role players need to be involved in order to sustain the efficiency and reliability benefits in the long term,” Rosen says. “Training inSouthAfrica is alsoattracting a
Delegates at the Pump Operation and Maintenance course in Secunda.
of the people involved to be ‘junior pump ex- perts’, whoknowwhenapump isnot being run optimally andwhat to look for when trying to improve the energy efficiency and reliability of a pumping system. This is a far better ap- proach to training than we have adopted in thepast,” concludesRosen, adding: “It ensures that plantmanagers get a real andmeasurable return on their training investments.” q
lotmore focus through thenewB-BBEE legis lation, which requires companies to spend a percentageof their revenueon training previ- ously disadvantaged staff. This can be turned into a major opportunity for companies to both comply with new legislation, as well as address energy efficiency issues and realise cost savings. “We at 2KG are striving to empower all
Dura 5s and 7s advance HPLV hose pumps TheVerderflexDuraisthefirstrealadvance in hose pump technology since the high- pressure hose. The Verderflex Dura 5 and Dura 7 combine a close-coupled pump’s compactnesswith traditional long-coupled pump benefits in superior high-pressure low volume (HPLV) dosing pumps. lime and similar highly abrasive chemicals at pressures of 5 to 8 bar with minimal downtime. Other features of VerderflexDura5and Dura 7 pumps include:
• Carefree dry running capabilities. • No clogging maintenance costs. • Long life, heavy-duty hoses. • True dry priming, eliminating pre- wetting and priming. • Superior secondary containment and viscous performance. In addition to the above advantages, the simple-to-useVerderflexDura5andDura7 provide scalable performance and low maintenance. They are an excellent chemi- cal dosing solution for water-treatment, brewing and food industries with much lower operating costs. q
Unlike traditional high shear pumps that reduce flocculent particle sizes and result in both increased chemical use and higher operating costs, theVerderflexDura5s and Dura 7s bring gentle pumping to sub-litre per hour flow rates. Off-gassing liquids, suchasHypo,oftencausetraditionalpumps to vapour-lock, however, the Verderflex Dura 5 and Dura 7 readily pump these liquids with ease. With no valves or stators to wear, Verderflex Dura 5 and Dura 7 can pump
Verderflex Dura 5 and Dura 7 HPLV dosing pumps bring gentle pumping to sub-litre per hour flow rates.
March 2018 • MechChem Africa ¦ 11
⎪ Pump systems, pipes, valves and seals ⎪
Pump maintenance is key to efficiency
Through a range of pump maintenance solutions, FLSmidth is implementing sustainable productivity-enhancing solutions including lifecycle costing, pump audits, condition monitoring and wear analysis.
S cheduledmaintenanceisasimportant for operational continuity as it is for performance excellence, according to Willie van Wyk, general manager responsible for Krebs pumps at FLSmidth. “Ensuring optimum performance of our pumps is our number one priority at FLSmidth,” says van Wyk. The preventative maintenance carried out on customers’ pumps helps to avoid any unnecessary plant stoppages or premature failures, ensuring an immediate financial benefit to the customer. “The Krebs millMAX™ slurry pump – de- signed for heavy-duty output and abrasive slurries – can be fine-tuned while it runs,” he says. “This feature, which is conducted on the suction-side sealing through an adjustable wear ring, avoids any recirculation and grind- ing of slurry which could lead to power loss.” This fine-tuning means that the pump does not have to speed up tomaintain higher levels of production. By closing the gap between the impeller and suction liner, the flow and head stays constant in the pump. And by avoiding a plant stoppage every time an adjustment is required, efficiency and throughput remains high. FLSmidth can draw on global experts in its Pump Technical Group, who bring their experience in a vast range of applications fromaround the world. VanWyk emphasises that scheduling maintenance interventions at regular intervals allows worn parts to be replaced in time, extending the lifespanof the equipment. An added benefit is that a large inventory of spare parts can be avoided, as change-outs and repairs can be planned. “This also eliminates the need for techni- cians to be called out unexpectedly, or possi- ble stock-outs that could prolong downtime,” he says. “Rather, the scheduling we do with the customer is in line with our aim of pro- viding an overall lower lifecycle cost – which also comes with reliability, reduced cost of ownership and lower power consumption by the equipment.” Througha rangeofmaintenance solutions, FLSmidth can improve sustainability and en- hance productivity. “These include a lifecycle cost focus, pump audits, conditionmonitoring andwear analysis,” says vanWyk. “Customers can choose from a number of options such as performance-based agreements, spare parts agreements,customisedtrainingprogrammes and tailored maintenance packages. “With the lifecycle cost focus, the goal
is for the service teams from both FLSmidth and the customer to devel- op ongoing programmes to improve pump performance and reduced operating costs. “This approach is generally directed at improving performance on a number of fronts, suchasreducingpowerconsumption, increasing bearing life and getting more life out of gland seals,” he adds. The aim of pump audits is to es- tablishabenchmarkforimprovement programmes by measuring system andpumpcharacteristics – suchas in- let and discharge pressure, flow rate andsolids concentration. Particle size is also analysed, along with the wear on individual pump parts. Condition monitoring of pumps is done to eliminate the occurrence of unscheduled maintenance. This is conducted by estimating the con- dition of bearings, evaluating the pump duty operation, documenting any severe vibrations that have been detected, and providing central- ised records for pump maintenance activities. The wear analysis function is to predict the wear life of pump com- ponents, andusually requires a pump to be stripped after a trial period to assess improvements. It would involve observing and correcting any unpredicted or unusual wear patterns, drawing on FLSmidth’s ex- perience in wear analysis. Individual part thickness needs to bemeasured andmonitoredas part of this process. “Our goal is to establish perfor- mance-based agreements with spe- cific measures to document results, andwehavehadahighsuccess rate in this regard,” saysVanWyk. “Webegin by measuring a customer’s existing Total Ownership Cost (TOC) and we use this as a basis for lowering this
A Krebs millMAX pump being used with a Krebs Technequip™ knife gate valve.
A Krebs millMAX pump being assessed by members of the maintenance team. optimal performanceof FLSmidthequipment, helping to build long term customer relation- ships based on FLSmidth’s strong position as a productivity provider. VanWyk emphasises the value of FLSmidth’s customised training programmes offered to customers, and how these improve overall pump knowledge and pump maintenance outcomes at the cus- tomer’s site. q
cost as a long-term customer benefit. Then, we establish key performance indicators to measure and document the results that we find in our trials, and identify the appropriate corrective action,” he says. “We then set goals and objectives for improvement, and report regularly on the progress that is made as we apply this corrective action.” Maintenance programmes impact on the
March 2018 • MechChem Africa ¦ 13
Made with FlippingBook Learn more on our blog