Tag Archives: Multotec


Screen media is a critical part of the metallurgical process, and it is therefore essential that the appropriate screen panel or screen panel combinations are selected, not only to improve efficiencies, but also to lower the overall cost of operation.  

This is according to Gerrit van den Heever, sales director at Multotec, who says that when it comes to procurement of screen media, few end users, and their procurement teams, ever think about the bigger picture – total cost of ownership (TCO), which considers not only the initial cost of the consumable, but also the cost of operation and maintenance.

“Although a screen panel is a relatively low priced component in a processing plant, there is often a big focus on this cost, at the expense of TCO, which in my view is a flawed procurement practice,” he says. “Incorrect media selection can result in the screen not being able to handle the duty requirements. Consequently, the impact on the bottom line can be severe”

In a dense media separation (DMS) plant, the cost of the ferro silicone or magnetite is significant. Effective screening can result in improved medium recoveries and huge savings. The other obvious benefit to effective screening is the avoidance of valuable product losses.

A range of factors should be considered when selecting a screen panel for the application. One of the principle parameters is whether the screening application is wet or dry. “In a wet application, the supplier should establish whether blinding, pegging and scaling are a problem. In a dry screening application, check whether impact and pegging are issues of concern. These parameters are key in selecting the right material, with the relevant physical properties,  in which the screen panel should be manufactured .”

Different materials of construction need to be considered with the most appropriate being selected for a given application. The company has invested in a substantial range of material compound manufacturing capabilities to meet different customer needs. These include 21 different types of injection moulded polyurethane compounds, 17 types of hand caste polyurethane compounds, 17 types of compression moulded rubber compounds, and 18 types of injection moulded rubber compounds (e.g. fire-retardant)

All screen panels are manufactured with tapered, self-relieving apertures, resulting in the unrestricted downward movement of any sized particle, reducing pegging and blinding.

Rubber screen panels – which absorb impact, reduce pegging and blinding, and improve wear life in coarse and heavy-duty applications – are suitable for both high moisture and dry applications. Wedgewire screen media is suitable for filtration, solid/liquid separation, classification, dewatering and concentration in mineral processing applications.

“It is important to deal with a reputable screen media manufacturer that can assess these application requirements and recommend the most appropriate screen panels and screen deck configurations for the application at hand,” says van den Heever.

Not only does Multotec offer a variety of compounds, but also various aperture sizes and configurations  to meet different customer needs. Overall, the company has over 1 000 apertures available to choose from. “If we cannot assist a customer out of this range, we will tailor a solution to suit the application,” concludes van den Heever.


The global reach of mineral process equipment specialist Multotec has been highlighted by the recent supply of its South African-manufactured slurry pumps to a chrome project in Kazakhstan.

According to Gerhard Hendriksz, general manager responsible for slurry pumps at Multotec, an order of 38 slurry pumps was delivered in mid-December 2021 through a collaboration of Multotec’s international business team and the company’s distributor in Kazakhstan.

“The pumps were produced according to the specifications provided by  Multotec’s distributor, ensuring the units will deliver the required duty for the end-customer,” says Hendriksz. “This includes being designed to withstand highly abrasive operating conditions.”

Certain chrome deposits in Kazakhstan boast some of the world’s highest concentrations of chrome oxide (Cr₂O₃) – up to 62% content – making the slurry particularly abrasive. The pump range that Multotec delivered includes models from the HD25 to the MD300, in metal and rubber-lined configurations to suit their respective duties.

An impressive turnaround time of just 10 weeks was achieved, with Multotec leveraging its trusted local supply chain that included foundry work, machining and other suppliers as well as collaboration with Multotec’s technical partner, 7D based in Perth, Australia.

Andre Burger, production manager responsible for pumps at Multotec, also emphasises that a close working relationship with end user and Multotec’s Russian-speaking business team ensured smooth preparation and delivery.

“Our distributor has in-depth knowledge of the customer’s applications and has the engineering expertise to ensure optimal product specification and performance,” says Burger. “Multotec will support the products with aftersales and support services, including availability of spare parts.”

Despite the trade disruptions related to the Covid-19 pandemic, Multotec has continued to perform strongly on the export front. Last year, it earned a place in the Exporter of the Year Awards – presented by the South African Capital Equipment Export Council (SACEEC).

Multotec supplies a complete range of pumps for medium and heavy duty slurry applications, including cyclone feed, spirals feed, mill discharge, tailings disposal, filter feed, effluent discharge and spillage. The range caters for flow rates from around 15 m3/hr up to 2,000 m3/hr.


With its latest sampling system that aligns with metallurgical accounting standards, minerals processing equipment leader Multotec now offers unprecedented levels of accuracy for effective plant optimisation.

The company’s Realtime Automated Metallurgical Accounting (RAMA™) system promises to deliver significant value by unlocking higher mineral content through improved grade control and recovery, as well as by optimising the consumption of reagents. The system essentially brings three sampling disciplines – metallurgical accounting slurry sampling, sub-sampling, preparation and analysis – into one solution.

“By integrating our advanced samplers with a sample preparation system that meets metallurgical accounting standards, we can feed online analysers with a fully representative and accurate sample,” says Modisaotsile Nyokong, process manager at Multotec. “While analysers can be accurate instruments, they cannot provide meaningful results if they are fed with inaccurate samples.”

Nyokong highlights that the RAMA™ online analysis feed preparation system extracts regular and full sample increments from slurry flow streams according to AMIRA P754 metal accounting standards, best practice standard and Theory of Sampling. This eliminates more than 80% of the total sampling error, and allows real time process control to be conducted to the highest standard.

“Samples are extracted from the production flow using automated mechanical samplers which are Theory of Sampling (TOS) compliant,” he says. “This is achieved by taking full cross-cut samples that are representative of the flow stream.”

The analysed slurry is therefore unbiased, presenting an accurate reflection of all the key parameters such as particle size, slurry density, settling velocity and mineral grade. He explains that process control samplers – including pressure pipe, poppet and shark fin type samplers – have traditionally been used to feed online analysers. However, these primary samplers do not comply with the TOS, with the result that poorly represented samples are analysed with high levels of precision – which is a futile exercise. 

“Our advantage with the RAMA™ system lies with feeding representative samples to online analysers, using correct sampler designs,” says Nyokong. “This produces real time results that represent the flow stream and are free of error or statistically significant bias.”

Multotec’s slurry sample preparation solution prepares and treats each analysis stream in its own line, making it ideally suited to analysers that deal with streams individually – avoiding cross-contamination. Where multiple streams are analysed through the same analyser source and detectors, some cross contamination of streams can occur with different grades or mineral properties – undermining the accuracy of the result. 

Over an analyser multi-stream cycle, the RAMA™ system can collect composite samples for each stream, says Willem Slabbert, sampling and magnetics product specialist at Multotec. This means that the analyser does not measure the instantaneous off-take stream ‘sample’ from the traditional in-line continuous discharge like process control samplers – which is only done about 30 minutes apart. 

“Rather, it measures the performance of each stream through multiple composite samples taken over the 30 minute interval,” says Slabbert. “This reduces the grade or quality variability per flow stream, and gives the plant manager a more representative monitoring of minimum and maximum process conditions – with precise values.”

The problem with ‘snapshot’ sampling of process control samplers is that stream properties can fluctuate before and after the analysis. This fluctuation is therefore not captured in the results. By contrast, the RAMA™ system’s composite sample accounts for all process variations over the analysis period.

Slabbert reiterates that sample analysis results are only as good as the sample presented for analysis, pointing out that this applies as much to online analysers for process control as it does to conventional laboratory analysis for metallurgical accounting.

“RAMA™ is also a cost saving solution, as separate process control samplers are no longer required,” he says. “The samplers’ purpose in our system is doubled up for both metal accounting and for process control – without the need for any compromise.”

Configured in a containerised and modular design, RAMA™ is a compact and mobile system. This allows for easy installation and retrofitting into any plant operation – where it can feed any type of online analyser. It can also be readily transported and commissioned, with flexibility for expansion where necessary. Layout options are available for plants which have primary and secondary sampling with a subsequent containerised sample preparation stations, as well as for those with primary sampling only and separate secondary sampling preparation. 

The RAMA™ system allows analysers, for the first time, to be fed with representative samples taken from the production flow stream. The innovative combination of existing equipment with proven track record into a modular, containerised solution will bridge the gap between metallurgical accounting accuracy and accurate process control. 

“The advantages of this novel combination of sampling global best practices into process control applications will unlock value for both analyser calibration as well as optimal, dynamic process performance,” Slabbert concludes.


Using its extensive in-house testing facility for material from a South African manganese producer, Multotec has defined a solution that will upgrade the quality of saleable concentrate while reducing the content of manganese in tailings. 

According to Faan Borman, technology manager : research and development at Multotec’s technology division, the customer had specific targets they wanted to reach. These targets aim to optimise revenue from recovered minerals and also improve environmental performance, as a level of more than 10% manganese in the tailings would require the dump to be classified as hazardous. 

“The test work we conducted was to improve recovery of ultra-fine material from the thickener underflow,” says Borman. “The financial benefit of better recoveries is to produce a richer concentrate, but it is also to reduce the metal content in tailings – so that it would not be regarded as hazardous waste.”

Two sets of test work were designed and conducted. In the first set, stockpile material with a metal grade of 16% was tested using Multotec’s UX7 ultra-fine spiral concentrator for the roughing and scavenging phases, while its SC21 five-turn spiral was used for the cleaning stage. This allowed the target saleable grade of 32% to be achieved, he says, but there was still some work to be done to reach the tailings target grade. 

“This required some out-of-the-box thinking for the second set of tests, where we ran the material over the wet high-intensity magnetic separator (WHIMS) with a vertical ring,” he says. “At the highest intensity, this was able to downgrade the spiral tailings material from 13 to 14% right down to 7% manganese – a significant improvement.”

He highlighted that for process plants to achieve the most viable solutions they must optimise the use of cost effective equipment and strategies. Given the higher cost of applying WHIMS technology, the testing procedure using spirals was able to remove gangue minerals and reduce the volume of bulk material before being treated by the WHIMS.

“Another benefit of this process was that about a third of the material sent to the WHIMS in this process could be returned to the spiral circuit for further upgrade to meet specifications,” he notes. “This considerably reduces tailings volumes, potentially cutting down the footprint of the tailings storage facility and extending its lifespan.”

Bornman says that the cost of managing tailings facilities in a compliant manner, and the tightening regulations and policies on tailings dams, are encouraging a trend to re-process them. Technology improvements in metal recovery over the years now makes these re-treatment efforts commercially attractive.

“We have had considerable success in applying the spirals together with the WHIMS, as it is key to ensure sufficient bulk reduction up front,” he says. “The process can be applied across a range of commodities, and we have also seen good results in minerals including chrome, iron ore, lithium and mineral sands.”


In the face of worldwide logistical and supply chain challenges, leading South African minerals processing original equipment manufacturer (OEM) Multotec has had a stellar export year – emerging as a co-winner in the large business category of the 2021 Exporter of the Year Awards last month.

Hosted by the South African Capital Equipment Export Council (SACEEC), the awards recognise exceptional achievement by manufacturers in the capital equipment sector in terms of value, volumes and export destinations.

“As a proud South African OEM for almost 50 years, we greatly appreciate this recognition, especially given the local and global headwinds that all businesses are currently facing,” says Jaco du Toit, managing director of Multotec International. “Local operational challenges include unreliable power supply and incidents of labour unrest in the country, while international logistical capacity remains severely disrupted by the Covid-19 pandemic.”

Lead times in some transportation segments such as ocean freight (port-to-port) have increased by around 35% while costs have doubled. Du Toit notes that Multotec has overcome these challenges and met their export targets for the year – continuing the journey of growing the group’s international presence. 

Having initiated its internationalisation strategy some 20 years ago, Multotec now earns about 55% of its revenues from exports. With about half of these exports going into sub-Saharan African countries, the group is also active in Europe, the Americas, Australia, China and the Commonwealth of Independent States (CIS), especially Russia, Belarus and Ukraine.

“The key to our success in exports has been our ability to maintain productivity and stability of our manufacturing operations, which embrace 60% local content,” he emphasises. “We have never deviated from our commitment to building our economy through innovation and expertise; we believe fundamentally in the power of local business to transform our country for the better.”

Multotec employs about 1,9000 people at its various sites around Spartan and elsewhere, and supports a large range of local suppliers and subcontractors in generating its wide product offering. It also invests heavily in skills development and SED projects. He explains Multotec’s export strategy is speed to market by as getting closer to customers wherever they are based, plus its ability to deliver a quality product on time at a competitive prices anywhere in the world.

“Underpinning our export success has therefore been our global network of strategically located subsidiaries in certain countries, supported by agents in others,” says Du Toit. “In Africa north of South Africa, for instance, we have companies in Botswana, Mozambique, Zambia and Ghana with strategic partners in Namibia, Zimbabwe, Democratic Republic of Congo, Guinea, Sierra Leone and Mauritania.”

This allows not only the export of equipment but facilitates an ongoing field service maintenance relationship and after-sales service to ensure the technology continues to add value on customer sites. The same approach has been applied in Canada through Multotec Canada, with about 60% of the supply line into that country being sourced from South Africa. The 14,300 m2 Spartan facilities also manufacture most of Multotec’s equipment supplied to Australia, Europe and the CIS.

“Having weathered a difficult couple of years since the outbreak of the pandemic, we have succeeded in our aim of not shedding any jobs,” he says. “As the mining sector surges ahead, we are now reaping the rewards of that achievement. At Multotec, we aspire to grow a truly South African brand to become a respected name in all mining sectors in the world.”


Innovation in Multotec’s proven hammer samplers allows two consecutive samples to be taken from the product stream in quick succession, ensuring two sets of accurate results – one for the mine and one for the customer.

“A single sample increment cannot simply be divided into roughly two equal parts,” says Refilwe Makgae, senior application engineer at Multotec. “This can result in up to five of the nine sampling errors occurring in a single step.”

She emphasises that each consecutive increment must instead be carefully diverted to its own bin, so that successive increments do not contaminate each other. Multotec has therefore developed a reliable flopper gate that is easy to operate and gives feedback about the flopper positioning.

“This ensures that a good seal is achieved, preventing sample cross-contamination,” says Makgae. “For existing operations where this new requirement is imposed, this innovation can be easily retrofitted.”

She notes that high levels of precision in sampling can only be achieved with fine design tolerances for each application. For this purpose, Multotec has developed software integration models across AutoCAD Inventor and programming code, to automate parts of the design. This process uses pre-programmed design logic and interpolates from the company’s data library which covers a worldwide footprint of over 800 hammer samplers in the field. 


In a crowning recognition of his career contributions to mining, Multotec business development executive Roy Roche was recently named Multotec’s Coal Person of the Year. 

This coveted award – presented each year by the Southern African Coal Processing Society – puts him among industry greats like David Horsfall, Johan de Korte, Dr Brian Stewart and Johann Engelbrecht, who he has always revered. 

“Having so looked up to these leaders in our field, and greatly respecting their influence on the development of coal processing, receiving this award is for me indeed very humbling,” says Roche. He feels proud to be associated with this rich lineage of expertise seeking to make coal a cleaner and more efficient driver of economic development. 

Roche highlights the innovative thinking of coal processing experts over the years, and the results achieved by transcending traditional disciplinary silos. As metallurgists have worked in greater collaboration environmental scientists, civil engineers and geologists, the processing of coal has transformed considerably to what it is today. 

His long career in coal processing began differently to most, he notes. Having studied zoology and botany in a natural sciences degree, he had in fact started work as a researcher in De Beers’ research laboratory. He then began a graduate programme with Anglo American, diving straight into shift work at Bank Colliery to learn everything about process plants from the ground up. 

“The technical and managerial foundation that this gave me was remarkable – and really gave me the best possible start to my career,” he says. “I was soon immersed in the world of processing coal, and realised what a vital role this work played in developing our economy while reducing our environmental footprint.”

By the tender age of just 27, he was already the assistant plant superintendent at Goedehoop Colliery – in charge of about 200 staff in a facility that produced over 10 million tonnes of coal a year. In 1988 came his big move to Multotec, where he has spent more than 30 years pushing the boundaries of mineral processing technologies and equipment. 

“After joining Multotec, I was soon involved in introducing our technical advancements to the coal processing industry, especially equipment like our screen panels, samplers, spirals and cyclones,” he says. “These and other technologies were an important part of improvements in plant efficiencies over the years to come.”

Coal processing has always comprised an important focus for Multotec, which has two branches – in Mpumalanga and Limpopo – servicing South Africa’s coal mining sector. He highlights the impact that Multotec has continued to have in the field of dense medium cyclones in cleaning coal while improving recoveries and dewatering. There is also ongoing evolution of the company’s coal spirals, and new standards set in sampling. 

“These innovations have had a significant effect on the coal industry not just in South Africa but globally as we took these developments into countries like Australia, Chile and Canada,” he says. 

Roche reflects on how far processing technology has come in the past three decades, particularly in reducing the environmental impact of coal. It has advanced the separation efficiency of coal from impurities, so that each element can be treated separately. 

“Filter presses, for example, have been able process thickener underflow, eliminate slimes dams, and control water quality so that anything discharged into the environment is sufficiently clean to meet the required standards,” he says. “Pollution control around the dumps and in the plants has also improved considerably; when I was working in plants, this was already a key concern where management wanted to see progress.”

This led to the ability to treat and recover fine coal, while removing discards and gangue material so that boilers in power plants can be better controlled and more efficient. There are also ongoing advancements toward the dry processing of coal. 


Responding to the rising demand, Multotec has added to its facilities two new rubber vulcanisation presses at its extensive local manufacturing facility in Spartan, Gauteng – raising quality levels while reducing lead times for customers.

The new additions have improved both the production capacity of the facility as well as the dimensional capability in the production of lifter bars, shell plates, head plates and grate plates for mill linings. 

According to Thando Makhoba, managing director of Multotec Rubber, the new hydraulic presses have larger daylight openings to accommodate higher throughput and larger dimensions of products.

One of the new presses, the largest yet installed by Multotec, is among the largest in South Africa’s wear lining industry. With a 2.7 m long platen size, it is 1.9 m wide and boasts a 1.1 m daylight and the press has a 3,600 tons pressing capacity.  

“This enables us to produce lifter bars up to 400 mm wide, with advanced human-machine interface (HMI) software and a locally developed PLC control system,” says Makhoba. “It also means we can improve our production rates, so that we reduce the lead time on these items for customers.”

He also highlights the safety benefits of the new units, with the HMI hardware and software allowing operators to have less physical engagement with the machines during production. Adding to efficiency on one of the presses are two stripping tables – one directly in front of the press to pull the mould out of the daylight – and a side stripping table to pull out the first mould to make space for the second. This allows semi-automated loading and unloading, further accelerating the process. 

Technical manager at Multotec Rubber, Waldo Verster, says the new presses allow Multotec to press more units per cycle, with one press capable of pressing between seven and 14 lifter bars at a time. 

“These presses also improve our ability to service the demand for integrated liners, allowing us to integrate up to two lifter bars and two shell plates – or two lifter bars and two head plates – into a single liner,” says Verster. 

“For the customer, these integrated liners are quicker to install, so they reduce mill re-lining time. And they are also safer, as they can be installed by a mill liner handler operated from outside the mill.”

A further opportunity for the new equipment is the market demand for larger lifter bars, as few companies can produce lifter bars measuring 400 mm in wide and 350 mm high. Makhoba notes that the installations demonstrate Multotec’s commitment to taking a technological lead in its sector, to optimise the operations of customers. 

“This allows us to deliver high local content in our products, in line with the aims of the Mining Charter,” he says. “To the best of our knowledge, we are the only mill lining supplier in the country with a local content certification from the South African Bureau of Standards.” 


Sustainability has become a key driver for leading minerals processing equipment specialist Multotec, promoted by its efforts in range of environmental, social and governance (ESG) initiatives.

Johan Robbertse, group financial director at Multotec, highlights that its ‘Our Multotec Way’ guides the culture and vision of the business in various aspects of sustainability. This approach reflects in the way that the company nurtures its people and conserves resources like energy and water, says Robbertse.

“In recent years, as global awareness about energy efficiency has grown, Multotec started looking at renewable energy sources,” he says. “This led two years ago to our first solar panel installation of over 400 kWh at our manufacturing facilities in Spartan, followed by a second project to take our self-generation capacity to 800 kWh.”

The company is planning a third solar installation at its facilities in East Rand and Tshwane to raise its capacity to 1,4 MW, which will provide about a quarter of the company’s electricity needs. Already, the positive environmental impact of Multotec’s solar facilities amounted to the removal of some 250 tonnes of carbon dioxide emissions. This is the equivalent of planting 7,000 trees. In addition, LED lighting and other initiatives in the workshops also save on power consumption.

“We also support our customers in the mining and power generation sectors to operate cleaner,” he says. “Our samplers, for instance, help to improve the quality of coal going into power stations, so output is more efficient with less emissions.”

Water quality and conservation is also in Multotec’s spotlight, with a mineral recovery range of equipment that generates cleaner water for mines. Multotec also assists customers in removing brine so that on-site process water resources can be retained in a closed loop, or discharged in a clean state. 

“Our social contribution includes our commitment to skills development and creating a culture of diversity,” he says. The company has supported over 350 learnerships since 2016, with special focus on women and people with disabilities. This has led to the training of 60 disabled learners, a number of which have been absorbed into the business. 

Economic transformation is another aspect of sustainability that Multotec has prioritised. In addition to its BEE compliant company status in terms of the Mining Charter, , the company recently created a 51% broad-based black-owned entity for its services operations. With almost 300 people employed in a country-wide branch network, this company supports the Mining Charter goals and promotes the local economy in the regions around key mining hotspots.

“The importance of local manufacture cannot be overstated when considering the long-term sustainability of our mining sector,” says Robbertse. “So we have taken an active role in working with industry bodies to advance the necessary certification frameworks for recognising local manufacture.” 

Already ahead of the pack, Multotec recently had its SABS certification as a supplier of South African manufactured goods renewed for another five years.


New mines or expansions rely on accurate test work to know how best to recover the minerals in an ore body; mineral processing specialist Multotec not only provides the processing solutions, but can also test material to inform clients’ financial and operational planning.

In a recent presentation to the South African Institute of Mining and Metallurgy (SAIMM), Multotec process engineer PJ Pieters and R&D engineer Jeantelle Rust outlined how the company’s extensive test work capability was put to use by industry.

“The process starts with accurate sampling – a field in which Multotec has developed a depth of expertise and a dedicated product range,” says Rust. “We prepare samples from clients with techniques such as filtration, drying, particle size distribution analysis and laboratory-scale float and sink analysis. We can also conduct sample splitting and packaging before the analysis takes place.”

Serving an international client base, Multotec has done test work on minerals including but not limited to gold, coal, lithium, mineral sands, copper, iron ore and tin. The work is carried out and supported by experienced metallurgists and product specialists. 

“Our expertise in physical separation allows us to test the samples using selected products from our portfolio, and ensures that the client gets the most effective solution,” she says. 

Test capabilities include gravity concentration using spirals as well as cyclones, magnetic separation, solid-liquid separation and water treatment related to metals recovery. 

“Accurate screening is also important, so our test facilities include Vibramech and LuCoTec vibrating screens to identify the best solutions to increase plant capacity, reduce wear and energy consumption, and optimise reagents,” says Pieters. 

There is also a trommel screen testing facility to provide insight into sizing or the removal of oversize material. Screening deck optimisation using deck maps helps clients find the best combination of open area and durability. The breadth of capability has led to many interesting tests being run, he says. 

While most test work is conducted at Multotec’s dedicated research and testing facilities, the company is also able to take certain equipment to a client’s operation for on-site testing to be done.

“This is a convenient way to conduct testing under normal plant operating conditions,” he says. “This kind of test work adds confidence to the client’s decision to invest in a specific solution.”

“These tests range from liners for bauxite and magnetic separation for wollastonite, to using cyclones to separate cow manure from grass and grit for use as a biofuel,” Rust says. “Testing with spirals has also helped clients find the best separation methods for material as varied as tantalite, wolframite and crushed computer components.”

Multotec’s test work feeds valuably into product development, continuously and cost effectively improving the company’s offerings based on its own R&D combined with client requests. The solutions can often be turned around much quicker than expected, using rapid prototyping with 3D printing and CNC machining powered by specialised modern software.

“Our test work has allowed us to modify cyclones, for instance, for innovative applications like removing plastic from sand or to vary cyclone inlet head geometries and ratios,” she says . “It has recently led to solid-liquid separation developing a South African-manufactured filter press.”