MechChem Africa January-February 2022

MechChem JAN-FEB 2022 AFRICA

champions of ecological transformation

This month: Mine ventilation and the VUMA simulation advantage

Mobile power for a cooler and cleaner environment

Vibrating screen designs informed by fundamentals

Mobile HVAC: busting the perception of over-engineering

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CONTENTS Maintenance solutions and asset management 6 Werner Pumps’ SA-manufactured boiler tube cleaning equipment Sebastian Werner, MD at Werner Pumps, talks about the role played by his company’s cleaning equipment in keeping boiler tubes in peak working condition. 7 WearCheck embraces communication tech 8 thyssenkrupp’s condition-based maintenance solution 9 Ultra-reliable lubrication from SKF Water, wastewater and pumping solutions 10 Ten years on, the Warman DWU pump remains a ‘local hero’ In the competitive world of pumps, gaining the technological edge is not easy; but ten years ago the South Afri- can engineering team at Weir Minerals Africa achieved just this – and the results are being enjoyed worldwide. 13 Tough conditions call for Grindex drainage pumps 14 StitchWise and ZebraTube: a local dewatering success story Minerals processing and materials handling 16 Vibrating screen designs informed by fundamental parameters MechChem Africa speaks to Kenny Mayhew-Ridgers of Kwatani about the holistic design approach for vibrating screens. 18 Pressure on cement, mining for sustainable production 20 Dust control vital to miners’ health 22 MineARC’s ChemSAFE Safe Havens: the gold standard Heating ventilation and air conditioning 24 BBE Consultants and the VUMA simulation advantage The BBE Group has released the 2021 version of its flagship mine ventilation simulation software, VUMA-network, which is being offered free to the mining industry. MechChemAfrica talks to Russell Hattingh, MD of BBE Consulting and Hannes Potgieter, Senior Ventilation Consultant. 26 Booyco mobile HVAC systems: busting the perception of over-engineering PowerGen, PetroChem and sustainable energy management 28 Zest WEG supplies SA’s new helium gas project Zest WEG is supplying locally manufactured transformers, switchgear and substations to South Africa’s exciting onshore natural gas and helium project, Tetra4, which is being developed by Renergen near Virginia in the Free State province. 31 IdentiQ digital twin for sustainable, flexible and secure power grids Corrosion control and coatings 32 Cooling tower water treatment – understanding the options JP Thyse, technical manager at Allmech, talks about how to protect cooling towers, evaporative condensers and hot and cold water-treatment systems from scale, corrosion and microbiocides. Local manufacturing and food processing 34 SEW-Eurodrive’s build strategy: the pride of Africa MechChemAfrica talks to SEW-Eurodrive’s, Raymond Obermeyer and Jonathan McKey about the strategy that has enabled growth in difficult times and their modern 26 000 m 2 facility in Johannesburg. Innovative engineering 38 Mobile power innovation for a cooler and cleaner environment Atlas Copco’s David Stanford talks about some the innovative solutions emerging from the company’s Power Technique business line, driven by the global group’s commitments to help meet the UN’s sustainability develop- ment goals(SDGs) and the Paris Agreement. Regulars 2 Peter’s comment: Davos, Klaus Schwab and the multi-stakeholder sustainable future 4 On the cover: Water reuse and ecological transformation: MechChem Africa talks to Miles Murray, about Veolia’s expertise in water and resource reuse and the role the company plays in delivering ecological transformation. 36 Products and industry news 40 Back page: Mechanised machinery training enters virtual age

Published bimonthly by Crown Publications (Pty) Ltd 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 Editor: Peter Middleton Design: Katlego Montsho 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. e-mail: peterm@crown.co.za Advertising: Elmarie Stonell e-mail: elmaries@crown.co.za

Transparency You Can See Average circulation Jan to Jun 2021: 7 196 Printed by: Tandym Print, Cape Town

Front cover: Veolia Services Southern Africa (VSSA) Contact: Veronica Stevens Tel: +27 11 663 3618 veronica.stevens@veolia.com www.veolia.co.za

January-February 2022 • MechChem Africa ¦ 1

Davos, Klaus Schwab and the multi-stakeholder sustainable future

Peter Middleton

I write this during the first week of Davos 2022, the annual meeting ofWorld Economic Forum (WEF). My perceptionof the event in thepast has been somewhat cynical, just another talk shop involving the powerful and rich striving to prove that they really, really are trying make the world a better place. During this week, the Forum is again launching several initiatives: to accelerate the race to net- zero emissions; to ensure economic opportunity of nature-positive solutions; to create cyber resilience; to strengthen global value chains; to build economies in fragile markets through humanitarian investing; to bridge the vaccinemanufacturing gap; and to use data solutions to prepare for the next pandemic. All verynobleandrelevant, but cananyof the ‘initia- tives’, nomatter how passionately argued, change the politically expedientwaywe are ledor the entrenched financial systems that drain wealth from the poor and advantage the super-rich? “Everyone hopes that, in 2022, the COVID-19 pandemic and the crises that accompanied itwill finally begin to recede,” writes Klaus Schwab, founder of the World Economic Forum in the introduction to Davos 2022. Yes, I guess we all do. I wondered who Klaus Schwab really was, so I looked him up. First off, I note he is a professor, a positive in my biased view of humanity. Then I read that he founded the WEF in the same year as he wrote a book called, in English, ‘Modern Enterprise Management in Mechanical Engineering’. So he is also an engineer! Written back in 1971, this book argued that, to achieve long-term growth and prosperity, the man- agement of a modern enterprise must serve not only shareholders but all stakeholders. Schwab’s ‘champi - oning’ of the multi-stakeholder concept, I read, was at the heart of the WEF’s inception, and the Forum is now the world’s foremost platform for public-private cooperation. Also under his leadership, the Forum has been a driver for political reconciliation in different parts of the world. One of these brought NelsonMandela and FWde Klerk to the 1992 Davos meeting to jointly ad - dress assembled world leaders. Klaus Schwab’s role in promoting South Africa’s peaceful transition had begun several years earlier, however, with planning and networking to identify and nurture future South African leaders. The 1990 announcement byFWdeKlerkof theunbanningof the ANC, the Communist Party, the PAC and the release of many of South Africa’s other leaders from Robben Islandwasfirst heardbymore than1000of theworld’s top business and political leaders and thinkers in the

concourse of that year’s Davos conference. “Butmajor global challenges await us, fromclimate change to rebuilding trust and social cohesion. To ad- dress them, leaders will need to adopt new models, look long term, renewcooperation and act systemical - ly,” Schab continues in his introduction toDavos 2022. And his intentions now start to strike me as credible. One of the presentations on the Davos 2022 Agenda (January 20) is entitled ‘ESG Metrics for a SustainableFuture’. “Weare transitioning toanewtype of capitalism, melding the creation of prosperity, serv- ing society and caring for the planet,” reads the blurb. Environmental, social and governance (ESG) met- rics have been unveiled by theWEF for use in business reporting to provide a common set of ‘disclosures’. Developed in collaboration with the four major ac - counting firms, Deloitte, EY, KPMG, and PwC, as well as representatives fromcorporations, investors, stan- dard-setters, non-governmental and international or- ganisations such as the Climate Disclosure Standards Board, the metrics are centred on four pillars: Principles of governance, which reflect a company’s purpose, strategy and accountability, and include criteria that measure risk and ethical behaviour. • Planet, to highlight a company’s dependencies and impacts on the natural environment. It in- cludesmetrics such as greenhouse gas emissions, land protection and water use. • People, which features the company’s equity and its treatment of employees and includes in- formation about diversity, wage gaps and health and safety. • Prosperity, which details how a company affects the financial wellbeing of its community through measures such as employment and wealth gen- eration, taxespaidand researchanddevelopment expenses. Our cover story for this issue from Veolia Services SouthAfrica is about water reuse and resource recov- ery. While describing the technologies and successful projects involved, MilesMurray outlines Veolia’s core purpose: delivering ecological transformation and the UN’s Sustainable Development Goals (SDGs). The global Veolia Group has recently released its multi-faceted performance ‘compass wheel’ to guide the course of the company in the long-term. It sum- marises a shared progress approach that involves all Veolia employees and benefits all stakeholders, with a view tomakingVeolia amodel company for delivering ecological transformation. It is heartening to see the work Klaus Schwab and the WEF has done over the years delivering some real impact.

Comment

MechChem Africa is endorsed by:

2 ¦ MechChem Africa • January-February 2022

Water reuse and ecological transformation

MechChemAfrica talks to Miles Murray, director of business development for Veolia Services SouthernAfrica (VSSA), about water reuse and the local roleVeolia is playing in delivering on the global Group’s core purposes, ecological transformation and the UN’s Sustainable Development Goals (SDGs).

up this water reuse project frombeing purely about industrial water provisioning to being a full-on reuse project toprovide potablewater and sanitation to the municipality,” he says. In principle, he says, the current project is probably only twomembrane-based process - es short of being able to produce potable wa - ter. “We simply need to add an ultra-filtration (UF) and a reverse osmosis (RO) treatment process to produce drinking water compliant with SA’s SANS 241 standard,” he informs MechChem Africa. “We remaindetermined toensure that this flagship project remains successful and con - tinues to fly the Veolia brand. We will, there - fore, doeverything inourpower toensure that

it continues to run smoothly,” he adds. Globally, to promote ecological trans - formation across the planet, Veolia’s first priority is to implement as many of the UN’s SDGs as possible, and 13 of these goals are being explicitly targeted. “This means that everything we do is aligned to these long- termobjectives andwewill never allowshort term gains to tarnish our brand. Veolia is a truly international entity that is committed to protecting the future for our children’s children,” Murray says. “This is not all about delivering advanced technologies. Ourmandate is to also focus on employment, for example, which is another of theSDGs. Sohere inSouthAfrica, we continu -

“W e spent thefirstweekof 2022preparing tenders for ongoingwater reuse projects, in anticipation of their renewable and possible expansion,” beginsMilesMurrayofVeoliaServices South - ern Africa (VSSA). One of Veolia’s historic flagship projects hasbeen treatingwastewater andsupplying it for reuse to local industries inKwaZulu-Natal for the past 20 years. The project was one of the firstwater related public private partner - ship (PPP) of its kind and the first to adopt a newcontractual model for financing new infrastructure. The municipal owner

didn’t have tofind theupfront capital to get the project up and running, and the project is estimated to have freeduppotablewater for use by 400 000 people in the

area, while actually reduc - ing the need for municipal investment in new water treatment infrastructure in the area. The private industries

using the water benefit - ted from a saving of 52% in water tariffs by reduc - ing the amount of potable municipal water consumed; the municipality and the local community benefitted from the freeing up of scarce potable resources for human use; and the municipality be - came known as an early adopt - er of sustainable water-resource development. “We are currently still contracted to ‘sell’ high quality (nearly potable) water to manufacture fine paper, and refinery process water,”Murray tells MechChemAfrica, adding that the new tender includes the additional supply of potable water for the local com - munity. “This is very exciting.We are stepping

By embracing a shared and responsible approach for the benefit of the planet, society, its clients, employees and shareholders, Veolia’s core purpose is to deliver ecological transformation.

4 ¦ MechChem Africa • January-February 2022

⎪ Cover story ⎪

bills and valorised biogas and the recovery of other resources. “Financiers are often willing to fund the capex, while Veolia can put a deal together based on a monthly service fee to operate and maintain the plant for the duration of the contract. This ensures that clients benefit from the financial and environmental values while demonstrating responsible resource management,” Murray points out. “This is pretty much what we have been piloting inKZN for the past 20 years.Without having to go to high-end technologies, we are now in a far better position to implement efficiency optimisation improvements and monitoring systems to give early warnings of changes to the inflow, TDS loads or system filtration efficiencies. When wastewater of an unexpected quality enters a treatment system, the fouling on downstream mem- branes and such can quickly become hugely problematic and expensive. Careful monitor- ing and management can help to avert such problems,” he explains. Making sure that water is fit-for-purpose can reduce scaling, fouling of pipes and cor- rosion. Citing a success in the gold mining industry he says a refinery was able to save around tens of millions per year by reducing the corrosion damage on its pumps. “Each pump was costing in the region of R8-million and the mine was having to replace up to six pumps a year. By getting the water quality right, only two pumps had to be refurbished in the following year, which saved on both the pump replacement costs and on associated downtime,” he says. “Veolia Services is an environmental com- pany that, as well as water, looks at energy and solid waste management. Underpinning all of these services, we strive to deliver the SDGs by embracing a shared and respon - sible approach for the mutual benefit of the planet, society, our clients, employees and shareholders. “We believe this makes Veolia a model company fordeliveringecological transforma- tion,” Murray concludes. q

Veolia’s Memthane ® technology uses anaerobic biological treatment and membrane separation to provide potable water, biogas and a sludge suitable for fertiliser.

ally strive tofind improvementson traditional, well-known treatment technologies.”

thewastewater treatment requirements from end toend. Clients come touswithaneffluent andaskuswhatwe candowith it.Wewill then analyse the treatment needs and identify the offtakes, their potential value and the residue disposal costs. From a water perspective, we canmake thewater environmentally friendly and safe at many levels: for direct use as grey water in the factory, for discharging back into the environment as surface water, or we can treat it for use at any quality level required,” Murray informs MechChem Africa . In addition, issues such as pipe bursts can causewater dependent businesses tocome to a grinding halt for two to three days. Properly managed reuse systems can significantly reduce these risks. While water reuse is gaining traction in South Africa, Murray says that water costs are still reasonably cheap compared to inter- national standards, whichmakes investments harder to justify. “We are responding to this challenge by putting funding mechanisms in place to make it easier for users to invest in reuse systems such as these,” he notes. Options include securing finance for an eight to ten year repayment period on capex, which can make a business case quite strong with respect to returns. “We are happy to consider co-funding of such systems or success-based models that are funded via shared savings accrued from reduced water

Water reuse in the food and beverage industry

Another area of increasing demand forwater reuse technologies in South Africa is inwater challenged areas such as the Eastern Cape, where businesses are coming under pres- sure to reduce their offtake from the local municipalities. “We are currently running a resource recovery project inMossel Baywith a dairy producer, for example, withwastewa- ter volumes that contain organicmatter from milk, yoghurt and cheese residues,” Murray continues. Using Veolia’s Memthane ® technology, which combines anaerobic biological treat- ment andmembrane separation, the company can provide an innovative and environmen- tally friendly waste water processing system that produces a methane rich fuel gas from organic solids, while alsodelivering highqual- ity potable water for reuse in the process. In Mossel Bay, themethane gas is stored inpres- surised tanks for use in the factory’s boilers and even the sludge that remains is reused by the local farming community as a fertiliser. This project is currently converting a minimumof 60%of thewastewater topotable standards. This is combinedwith the incoming municipal stream on the factory side of the water meter, reducing demand and associ- ated costs. “If a producer is paying R34/m 3 for water and the water recycling costs are between R18 and R22/m 3 , then installing a wastewater treatment plant can be very cost effective as well as environmentally friendly. “While the company gets kudos for reduc - ing its offtake and for reducing municipal ef - fluent treatment requirements, we estimate thepaybackperiodbasedonthecurrent reuse rate to be in the region of eight years – and this doesn’t include the cost reductions due to expenses and fines associated with having to safely dispose of these effluents, which can ratchet up very quickly. “Going forward, we seek to take care of

One of Veolia’s flagship projects has been treating wastewater and supplying it for reuse to local industries in KwaZulu-Natal for the past 20 years.

January-February 2022 • MechChem Africa ¦ 5

Werner Pumps’ SA-manufactured boiler tube cleaning equipment Sebastian Werner, MD at Werner Pumps, talks about the importance of regular cleaning of ash build-up and slag deposits that form on boiler tubes and the role played by his company’s range of trailer-mounted high-pressure cleaning equipment in keeping boiler tubes in peak working condition.

F or over 30 years, Werner South Africa Pumps & Equipment has been designing, manufacturing, supplying and maintaining special- ist high-pressure jetting equipment. The company has built a reputation as a local industry leader through its focus on deliv- ering high-quality, low-maintenance, 100% South African manufactured products that last, all while considering clients’ budgets. “To keep power plants and other equip - ment operating efficiently, it’s important to undertake regular cleaning of the boil - ers. Over time, ash build-up forms slag deposits on the boiler tubes, which act like a layer of insulation over them. This means more and more fuel is required to get the boilers up to temperature and to produce the same output. It also results in higher carbon emissions because of additional fuel usage,” explains Sebastian Werner, MD at Werner Pumps. A key offering in this regard is Werner Pump’s range of trailer-mounted high-pres- sure cleaning equipment to help power - and other - utilities and their contractors keep their boiler tubes in peakworking condition. “Our 1 000 bar and 1 200 bar, V8 trailer units are ideal for scale and slag build-up cleaning applications,” continues Werner. “Water pressure jet cleaning is also used for condenser applications, often used in under- groundmines. Using our high-volume pumps and jets, we can reach the full distance of the boiler/condenser tubes,” he says. In a recent Hendrina power uti l ity cleaning application, the boiler tubes were over 9.0 m long with an inside diameter of roughly 23 cm. “Our units were able to run for more than an hour at a go, for what is known as ‘online cleaning’, which is cleaning while the boiler is in operation. Although this is a delicate operation, it means that no plant downtime is necessary. We were also thrilled to hear from the contractor that our 100% locally manufactured equipment was able to run longer and more efficiently than previously used equipment on the market. It’s always gratifying to see our equipment stand up to the test, and to have a satisfied customer,” he adds. Werner says that scale deposits on firetubes are often worsened by burn-

Werner Pump’s range of trailer-mounted high-pressure cleaning equipment helps to keep boiler tubes in peak working condition.

Water pressure jet cleaning using 1 000 and 1 200 bar V8 trailer units is ideal for scale and slag build-up cleaning applications and it can also be used for condenser cleaning applications in underground mines.

ing lower-quality fuels or by incinerating materials that don’t burn cleanly. He cites medical waste incineration applications as an example. “It’s important to clean tubes regularly for optimum heat transfer,” he continues. “Our units can be ordered as electric or diesel driven versions. They can be skid-, trolley- or trailer- mounted, depending

on the customer’s preferences. We stock a range of specialist nozzles to ensure we provide the best solution for each specific application.” The same type of equipment can also be used for cleaning rubber lining frompipelines, while the larger 2800barWerner Pumps unit is ideal forpaint andrust removal applications. www.wernerpumps.com

6 ¦ MechChem Africa • January-February 2022

⎪ Maintenance and asset management ⎪

WearCheck embraces communication tech

Using current technological innovations, condition monitoring specialistWearCheck is now able to use the company’s sophisticated online system to send customers oil analysis and equipment condition reports viaWhatsApp, giving more immediate and convenient access to users of WearCheck services.

M anagingdirectorNeilRobinson says WearCheck constantly explores how technology can enhance the customer experi- ence and continuously improves condition monitoring techniques. WearCheck’s ITmanager, Eddie Perumal, explains why WhatsApp is currently be- ing used in this regard: “WhatsApp has proven its convenience as an integral part of everyone’s daily life, and it adds value by allowing us to communicate in real-time with maintenance teams who may be on the factory floor with their mobile phones, rather than waiting until they are sitting behind a desk checking emails. Therefore, we felt it was fitting to incorporate the op- tion of communicating with our customers via WhatsApp,” he says. Cus tomers can se l ect f rom three WhatsApp message options – a one page report, a two page report or a summary status. These include fleet information, problem type and diagnosis, and apply to critical and urgent samples.

Another power fu l repor t i ng too l i s WearCheck Online, a web-based system that allows customers to view their sample report and fleet information, as well as submit their sample registration details and feedback. WearCheck Online comes with a variety of features to assist customers to manage their oil analysis programme. Some of these include: • Current samples list, which shows unread reports. • Print sampling labels using A4 self- adhesive labels. • Trend-based graphs, problem-type graphs and pivot tables. • Component analysis, enabling view- ing of the results of one or more com- ponents in a single graph. • Basic user information for staff in the reporting hierarchy, including reports read, sample submissions and feed- back entered. Various search options and filters are also available, including sample history and equipment or component searches.

An extens ion to the onl ine system – WearCheck ’ s mobi le app , whi ch was pioneered four years ago – has been well received in the marketplace. It offers simi lar features to the onl ine system, with the option to ‘Ask a diagnostician’, where the customer can enquire about a specific sample. Customers can also use their mobile devices to quickly scan their sample barcodes. Ma n y i n d u s t r i e s b e n e f i t f r om WearCheck ’ s serv i ces , among them mining, earthmoving, industrial , trans- port , shipping, aviation and electrical operations. As optimal machine condi- tion is critical in all these industries, and the WhatsApp service enables real-time maintenance issues to be shared, enabling instant decision-making, the new service will add enormous value to our condition monitoring services,” Robinson concludes. To sign up for WearCheck’s WhatsApp service, the company’s customer services division can assist via email or telephone. www.wearcheck.co.za

In South Africa, WearCheck performs oil analyses from laboratories in Durban, Johannesburg, Middelburg and Cape Town.

January-February 2022 • MechChem Africa ¦ 7

thyssenkrupp’s condition-based maintenance solution

Francois de Villiers, area manager for thyssenkrupp Industrial Solutions for the Western Cape and Namibia, talks about the company’s condition-based maintenance approach, citing some successful refurbishments that highlight the advantages of this service solution.

was also replaced with an energy chain. Although thyssenkrupp is the original equipmentmanufacturer (OEM) of these two shiploaders, it does not mean the company’s expertise and capabilities are limited to its own equipment. In fact, thyssenkrupp is close to completing a condition-based refurbish- ment project ona Stacker/Reclaimer thatwas manufactured by a third party. De Villiers attributes a number of factors to the success of thyssenkrupp’s condition- based refurbishments. “First, our highly skilled team of design and field service engi - neers and experiencedprojectmanagerwork alongside our customers, combining all the findings and reports in a working document. This forms the backbone of our condition- based maintenance strategy. Second, the end-user experience and practical, hands-on, involvement must never be underestimated. Subsequently, we always liaise with the customer’s maintenance team and consult breakdown reports when the scope of work is defined,” he explains. “Also playing a key role in the successful deployment of condition-based refurbish- ments is the expertise of our highly accom- plished team and its in-depth pool of know- ledge,” affirms De Villiers. “This enables us to assist customers irrespective of the size of their maintenance or refurbishment require- ments. Moreover, asmany of our design engi- neers have been involved in the initial design and manufacture of our machines, they are equipped with the necessary know-how and skill sets to implement new improvements andupgradesduringrefurbishments,”headds. The involvement of thyssenkrupp’s field service engineers in the complete value chain of condition-based refurbishments ensures that realistic schedules as well as detailed method statements are prepared to ease planning for site activities and tomitigate risk during maintenance. “We believe in strong teamwork between customer and contractor, and we are flex- ible to the structure- and responsibility-split that best suits the customer: be that on a consultancy basis, taking responsibility for a turnkey solutionor providingon-the-job skills training,” concludes De Villiers. www.thyssenkrupp-industrial-solu- tions.com

A refurbishment by thyssenkrupp Industrial Solutions has extended the service life of these two 20-year old shiploaders at Saldanha Bay by a further 10 years.

W hile there canbenoargument against the crucial role that maintenanceplays inoptimis- ingoverall plant performance, adopting the correct maintenance strategy is equally important. Although preventative and corrective maintenance can add value, they alsohave limitations: Preventativemain- tenance supports maintenance teams by enabling the advanced planning of mainte- nance activities, but it can also lead to over- maintenance, placing a burden on labour and maintenance costs. Corrective maintenance, on the other hand, is not ideal in a high performance pro- duction environment where machine avail- ability is crucial or, more specifically, where capital outlay for spares and redundancy is restricted. “The solution therefore is to extract the best of both through a condition-based maintenance strategy that combines the advantages of preventative and correc- tive maintenance into a win-win solution,” says Francois de Villiers of thyssenkrupp Industrial Solutions. “The implementation of acondition-basedmaintenancestrategyhelps to avoid potential conflict between produc - tion and maintenance engineering teams by aligning the teams’ respectivescopesofwork.” De Villiers points out that a condition- based maintenance approach also helps to cultivate a healthy culture within an organisation. thyssenkrupp Industrial Solutions, as a

market leader and employer of choice for materials handling equipment in the mining industry, has been expertly supporting cus- tomers with condition-based maintenance solutions for the past decade. The company recently completed a mid-life refurbishment on two 10 000 t/h shiploaders operating at Saldanha Bay, which has extended the life of these 20-years-old machines by a further ten years. According to De Villiers, owing to the ex - treme environmental conditions on the quay where the shiploaders are in operation, ex- tensive structural repairsweredone together with the application of a three-coat corrosion protection. Unpacking the scope of work, De Villiers explains that all themechanical drives on the shuttle inside the boom, on the slew system and the travel bogies were replaced as were the respective variable speed drives (VSDs), as these items were obsolete with limited support from the manufacturers. Latest technology safety sensors were installed to ensure a safe environment for personnel and equipment. No limitations were applied to the scope or detail thyssen- krupp executed, from software upgrades; to themachine’s control system; to replacing the hydraulic luffing cylinders on themain boom; and thecooling systems for themainconveyor belt gearboxes. Consultation with the end-user mainte- nance team prior to the refurbishment lead to improvements to the design of transfer chutes, which were replaced; a cable festoon

8 ¦ MechChem Africa • January-February 2022

⎪ Maintenance and asset management ⎪

Ultra-reliable lubrication from SKF Eddie Martens, SKF product manager for Mapro, introduces the SKF System 24 TLSD single point automatic lubricator Series, which offers perfect lubrication solutions for seamlessly meeting both constant and while-running lubrication requirements.

L ubrication requirements are deter- mined by type of application and operating conditions. While certain applications need constant lubrica- tion, others may require lubrication only when equipment is running. Irrespective of the type of application and the lubrica- tion requirements of machine compo- nents, extreme reliability and accuracy are pre-requisites because under- and over-lubrication can result in cata- strophic and costly equipment failure and subsequent production stoppages. “The SKF System 24 TLSD Series has the perfect lubrication solution to seamlessly meet both application requirements,” saysEddieMartens, SKF Product Manager, Mapro. “There are two different types of lubricators in the TLSD Series – the electro-mechanical single point and cabled single point au- tomatic units. These TLSD lubricators deliver ultra-reliable lubrication and are ideal for applications that require additional monitoring.” Theelectro-mechanical singlepoint automatic lubricator is ideal for critical applications that demand constant lu- brication. Performing optimally under variable temperatures, this lubrication unit is also suitable for remote installation in restrictive and hazardous locations, as well as for applications where high volumes of lubricant are required. The lubrication set is supplied complete with drive unit, battery

and compressors. The lubricator canbe set to deliver the correct quantity of lubricant over a set time period andwhen the equipment or machine is running. Offering an alternative to the battery powered drive unit, this cabled drive unit has a cable to connect the direct power supply and signal transfer lines. The cabled single point automatic lubrica- tor is based on the proven single point automatic lubricator TLSDseries. The main differentiators are the direct power supply from the machine’s control panel and thewired signal line to themachine’s PLC. The lubricator’s output signals can be used and stored within the equipment’s PLC. “Because the lubricator is powered from an ex- ternal power supply, it can be switched on and off when necessary,” notes Martens. “This allows improved ac- curacy of lubricant supplied compared to traditional manual re-lubrication techniques.” TLSD lubricators are suitable for direct and remote installationandhave a maximum discharge pressure of 5.0 bar over the whole dispensing period. Thereplaceablecartridgesarefilledwith 125 m ℓ or 250 m ℓ of SKF lubricant (grease or oil) that has been especially developed for bearing applications. The transparent cartridge reservoir allows fast, easyvisual inspection.Multipleaccessoriesare available for both TLSD lubricators. www.skf.com

pack, filled lubricant cartridge and matching support plate, making it ready for use. The cabled single point automatic lubri- cator has been specially developed for ap- plications that do not run continuously and is ideal for industrial equipment, elevators

The SKF System 24 TLSD electro-mechanical and cabled single point automatic lubricators can prevent under- and over-lubrication, which can both result in catastrophic and costly equipment failure and production stoppages.

January-February 2022 • MechChem Africa ¦ 9

Ten years on, theWarman DWU pump remains a ‘local hero’ In the competitive world of pumps, gaining the technological edge is not easy; but ten years ago the South African engineering team at Weir Minerals Africa achieved just this – and the results are being enjoyed worldwide.

J ust over a decade ago in September 2011, the first Warman ® DWU (dirty water unit) pump was sold to a mining customer inPhalaborwa inSouthAfrica. “The product was not necessarily a startling breakthrough,” saysWeirMinerals Africa head ofengineeringChristianStehle, “butwasrather an innovativeevolutionof anexistingproduct– as almost all technical advances are. “This high-lift dirty water pump was the perfect solutionforagap inthemarket thathad notbeenfullyrecognised,” saysStehle. “It really reflected the value of Weir Minerals’ long his - tory in pumps, working closely with customers and understanding their changing needs.” Developed locally from the design of its Envirotech ® pump range, to this day the Warman ® DWU pump remains fully manufac - tured in SouthAfrica. In addition to its enthusi- astic customer base in Africa, it has also found regular markets through the Weir Minerals

footprint abroad, he says.

“Having joined Weir Minerals Africa in 2004, I became very involved in the development of theWarman DWU pump concept fromthe time of the initial request

around 2007,” he says. “So the range is very close to my heart, and as a team we are extremely proud of its local and global success.” Filling the gap Critical modifications allowed the dirty water pump to essentially fill the gap between twowell-serviced market segments: theslurrypump – built for high levels of solids sus- pended in liquid – and clear water pumps. Theproblemofdirtywaterariseswhen the suspended solids in the pumped medium causeexcessivecomponentwearratesandpre-

maturemechanical failure. “TheWarmanDWU pump addresses this challenge, accounting in largepart for itssuccess.Therearemanypumps

A Warman DWU installed on a Multiflo pontoon barge. Designed to achieve relatively high heads while running reliably over long periods, the pump can easily accommodate pumping over long distances.

10 ¦ MechChem Africa • January-February 2022

⎪ Water, wastewater and pumping solutions ⎪

the pump could do, says Stehle. The perfor- mance of the first unit indeed lived up to its promise, and the customer was quick to order further units. Within a few years, the sales numbers rose steadily as the reputation of the Warman ® DWUpump spreadwidely. “This was quite a new experience for us in the mining sector, where purchasing decisions are usually quite conservative and must be basedlargelyonpastperformance,” he notes. Awareness of the pump was also disseminated through the WeirMinerals global network, and the Warman ® DWU pump found its place in the global product line-up. Today, there are loyal customers inregionsas far apart as Australia andCanada. More choice With time, customers came to Weir Minerals Africa with particular require- ments that could suit the demands of their applications. This led to a wider range of construction materials being introduced in themanufacture of theWarman ® DWUpump. For instance, stainless steel was offered as an option, and a whole range is now available in stainless steel and hard-wearing materials for

acidic applications. Whileitwasdevelopedinitiallywiththecon- ventional gland seal arrangement, there were soon requests for mechanical seals, which are nowastandardoptiononallpumps intherange. “Thenwecame toconsider centrifugal seals or expellers, which required us to implement some design modifications,” Stehle says. “So additional components were added to assist with shaft sealing and we have recently made the whole range available with this centrifu- gal seal option. This allows our customers to eliminatetheuseofcleanwaterwhenoperating the pumps, contributing to our sustainability strategy.” Stehle pays tribute to the expertise of his design team and the power of modern soft- ware design tools, allowing the application of Computational Fluid Dynamics (CFD) to improve performance and increase energy ef- ficiency. The 3D modelling of complex shapes, inconjunctionwith3Dprintingtechnology,now alsoopensopportunities for intricatemanufac- turing results. Combined with the company’s advanced material technology, the wear life of theWarman ® DWUpump canbe continuously improved, and its reliability and sustainability enhanced. www.minerals.weir

The locally designed Warman DWU is also fully manufactured and assembled at the Weir Minerals facility in South Africa.

that deal with either slurry or clear water, but few that address those ‘in-between’ applications,” he

says. “Our design therefore sets out to combinethewear resistance, robustnessand longevityof theslurrypumpwiththeefficiency features of clear water pumps.” The Weir Minerals Africa design team targeted applications such as emptying min- ing ponds and dewatering from underground, where the specific gravity (SG) was up to 1.05. At the same time, the units have to achieve relatively high heads, while running reliably over long periods. “We wanted a high-pressure rating, with the ability to run the pumps in series,” he says. “Pump operators can usually achieve a high head while pumping over long distances and most multi-stage pumps on offer can meet distance and height requirements, but not whenpumpingdirty liquids. Sothisbecameour differentiating factor.” A satisfied first customer Such was the need in the market that our first customer needed little convincing about what

Weir Minerals’ Warman DWU pump was designed specifically for dirty water requirements.

January-February 2022 • MechChem Africa ¦ 11

12 ¦ MechChem Africa • January-February 2022

⎪ Water, wastewater and pumping solutions ⎪

Tough conditions call for Grindex drainage pumps

The ideal drainage pump is one that performs reliably in the toughest of conditions, so operators do not need to waste time checking constantly on its performance. The Grindex range from Integrated Pump Technology offers this, and more. T ough pumping applications, such as on mine and construction sites, need a proven range of drainage pumps that are heavy-duty but

offer low total cost of ownership. These characteristics have been well proven in Grindex units. The Grindex range of drainage pumps handles water with abrasive solids up to 12 mm in size, and with high pH values from five toeight. Distributed locally by authorised southern African agent Integrated Pump Technology, Grindex submersiblepumps have a heritage going back over 60 years – with more than 400 000 pumps delivered. Drainage pumps are most suitable when users need to pump large quantities of dirty water, but still need to achieve heads of up to 200 m, or flow rates of up to 350 ℓ/s. These Grindex pumps deliver all that, and conve- nience besides. This is according to Integrated Pump Technology sales manager Jordan Marsh, who says the unique valve on Grindex drain- age pumps enables air cooling of the motor so they can run dry without a problem – and therefore don’t need babysitting. On the small end of this pump range, the Micro, Milli andMini models are all compact, lightweight and ultraportable. The Micro model’s lowpower consumptionmakes it ideal when running on a generator. The Milli looks similar to theMicro, but enables low suction, down to only a fewmillimetres, thanks to the unique non-return valve. Inthemediumsectionof theGrindex range are theMinex, Minette, Minor, Major, Master and Matador. Their revolutionary hydraulic design ensures high wear resistance, which dramatically reduces any performance drop that may result from long-termwear. “With their internal starter, SMARTmotor protector and optional level regulator, these pumps provide fully automatic protection and control without the need for an external starter,” Marsh says. “The soft starter means smoother motor acceleration, thereby pro- tecting the pump while reducing equipment wear and mechanical stress.” There are also two large Grindex drain- age pumps – the Magnum and the Mega. The Magnum, with its high quality and reliable design combinedwith ease ofmaintenance, is relied on for the toughest jobs. Made of cast

Grindex drainage pumps offer heavy-duty performance at low total cost of ownership.

Left: In the medium section of the Grindex range are the Minex, Minette, Minor, Major, Master and Matador, which offer high wear resistance to dramatically reduce the performance drop from long-term wear. Right:With its internal starter, SMART motor protector and optional level regulator, the Grindex Minex pump provides fully automatic protection and control.

iron, the Mega is ideal for operating in deep excavations where very high-head pumping is needed. Designed to handle pH levels from

six to 13, it can also be fittedwith zinc anodes for additional protection. www.pump-technology.com

January-February 2022 • MechChem Africa ¦ 13

StitchWise and ZebraTube: a local dewatering success story

MechChem Africa visits the manufacturing facilities of ZebraTube and StitchWise in Carletonville, South Africa, and talks to StitchWise managing director, Vincent Prior (right) and Carien Spagnuolo (left), the general manager of ZebraTube.

ZebraTube. Describing typical aboveground use of these bags, Spagnuolo says that most projects tend to be emergencies. “The ma- terials we use are specifically designed for retaining solids such as silt and sand while enabling water to filter through. They are now widely used for dredging the wastewa- ter storage dams at mining facilities, which get silted up over time and generally require cleaning every year to restore their water storage capacity. “Mixed slurries from slimes and waste- water dams are pumped into our ZebraTube geotextile tubes, which hold the solids while slowly, over a few weeks, allowing the water to drain back into the dam. Once filled and dry, the tubes are broken open so the dry solids can be loaded onto trucks for safe disposal,” she explains. “Sometimes, the slurry hasmineral value,” continues Prior, “in which case geotextile bags will be used which, once dry, can be lifted into trucks and easily transported to a reprocessingplant,” he says, adding that these bags are certified to be able to contain 5.0 t. of solids while being lifted. Using geotextiles for dewatering is a pas- sive alternative tomechanical solutions such as filter or belt presses, horizontal belt filters or centrifuges. “Mechanical solutions all use much more energy and are far more capital intensive. Since a lot of our work is for tem - porary dewatering applications, clients are reluctant to invest in permanent mechanical

S titchWise has its origins in themanu- facture of geotextile dewatering and backfill bags that support thehanging walls of some of the deepest mines in the world. “We have more than two decades of experience in retaining solids andpercolat- ing liquids through our woven and stitched geotextile bags,” begins Vincent Prior, MD of StitchWise and a director of ZebraTube. These backfill dewatering bags and tubes are manufactured from woven geotextile sheets locallymanufactured by Spilo in Cape Town. “Spilofirst extrudes polypropylene pel - lets into different grades of tape. The tape is thenwoven into continuous lengths of sheet-

ing for use in agriculture, mining, civil and outdoor applications. Many different weave patterns, strengths and widths are available, whichmakes thismaterial ideal for manufac - turingour extensive rangeof dewateringbags and tubes,” he tells MechChem Africa. While StitchWise’s focus remains mostly on the manufacture of bags for the un- derground mining and backfill market, ZebraTube ® was formed back in 2016 with a strong focus on above-ground dewatering. “We are a sister company formed as a 50- 50 partnership between Spilo, our textile manufacturer, and StitchWise, our bag and tubemanufacturer,” saysCarienSpagnuoloof

Currently, 4.0-million m 2 of geotextile material goes through StitchWise’s Carletonville factory every year.

14 ¦ MechChem Africa • January-February 2022

⎪ Water, wastewater and pumping solutions ⎪

solutions. By far the most economical way of dredging a silted up dam, for example, is to use geotextile bags or tubes,” explains Spagnuolo. “Since geotextile bags are consumable, this also enables the costs to be justified as an operational expense, as opposed to hav- ing to seek capex approval for an expensive machine,” she adds. “We have a number of different geotex- tile options in terms of filtration rates and strengths,” Prior continues. “Wherewe know the particles are relatively large, we can of- fer high-flow rate textile that enables the water to drain very quickly – and we have an onsite laboratory to test the solid retention and flowrate options for any slurry sample,” he notes. At theother extremeareultra-fines,which require a completely different weave to ad- equately retain the solids while still enabling dewatering. “Our smaller square bags used for recoveryare typicallymanufacturedusing this geotextile, which has a weave density of between 250 and 280 g/m 2 . ZebraTube’s geotextile weave patterns for dewatering are not widely known inter - nationally, but, with extensive experience in South Africa, Australia, Middle East and across Africa, the company has come to un- derstand how to solve a broad range of slurry dewatering problems. “Carien’s knowledgeof water and theadditional surface technologies that are needed, we believe, can compete with any of the imported products that some people believe to be superior,” notes Prior. “We are able to go to site and establish a customer’s exact needs,” he continues. “If, for example, a customer only has space for a 28.5 m geotextile we can manufacture that exact length so it can be delivered and placed on site quickly and easily, without the need to modify an imported standard length that is too long or too short. “We can easily adjust bag lengths or place additional anchor points so that boulders can be avoided or we can move the spout to best suit the outlet pipes of the pumps. None of this is possible if clients choose to use im- ported geotextile products,” adds Spagnuolo. Manufacturing: the local advantage “Because our entire manufacturing chain is local, we have the ability to respond to emergencies very quickly,” continues Prior. “In terms of delivering custom made dewa-

Each of the stitchers at the Carletonville facility of StitchWise can produce 2.5 km of seams per day.

tering solutions in an emergency, our lead times are shorter than any other geotextile manufacturer,” he asserts. “Plus , we have product ion capac- ity. Each of our stitchers can produce 2.5 km of seams per day and currently, 4.0-million m 2 of geotextile material goes through our Carletonville factory every year. When we get a call to make 10 000 bags in 10 days, we have an additional expansion facility and over 100 sewing machines to help deliver the order on time,” he informs MechChem Africa. Not only is it unnecessary for South African clients to look overseas for solutions, but ZebraTube’s export sales have more than doubled in the past year, proving that the company can deliver directly to over- seas plants – in Africa, the Middle East and Australia – in emergency timescales. “Even for the Australian market, our lead times are extremely short andwe offer a very high degree of flexibility. If we need to turn an export order around in three days, we can make it happen. The longest lead time is shipping and, in an emergency, we can fly the order to the client, which means that dewa- tering can often start within five or six days of an order being placed,” he says. Prior tells of a current order for a client in the Middle East: “Initially, this client was very keen on our customisation capabil - ity and came to us wanting to know exactly where and how our ZebraTube dewatering solutions were manufactured. For current orders, this client gives us five days to get the bags stitched, boxed, crated, palletised and

sent to OR Tambo International Airport for flying to site. The mere fact that this client is willing to bear the cost of flying our product out of South Africa proves that he sees our pricing as highly competitive compared to other global geotextile manufacturers,” he points out. Locally, ZebraTube operates its own fleet of trucks to rapidly service mining and wastewater facilities in South Africa. “When clients require a quick solution for a dewater - ing taskwith a small laydown area, we supply our geotextile bags, whichwe hold in stock to ensure we can respond rapidly. These bags are also used as an interim emergency solu- tion while we manufacture the dewatering tubes needed to complete the task. “Large tubes are almost always custom made to order in another of our facilities on this site,” he adds. Becausewe are flexible, we can adopt a fit-for-purpose approach, making sure that the solutions we put onto a site will meet the needs specified by our clients without being overdesigned or unnecessarily costly,” says Prior. WeareaSouthAfricanmanufacturingand employment success story. The geotextile material we used ismanufactured in Paarl by our partner company, Spilo, and we employ 145 people in Carletonville to custom stitch the geotextile bags. As well as servicing South Africa’s mining industry and mitigat- ing against environmental harm, ZebraTube products are nowalso being exported, which generates foreign revenue for our country,” Spagnuolo concludes. zebratube.co.za

January-February 2022 • MechChem Africa ¦ 15