Tag Archives: chrome

Multotec supplies 38 slurry pumps to Kazakh chrome project

Mineral process equipment specialist Multotec’s global reach has recently been highlighted with the supply of 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,” Hendriksz said. “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 Multotec delivered includes models from the HD25 to the MD300, in metal- and rubber-lined configurations to suit their respective duties.

A turnaround time of just 10 weeks was achieved, with Multotec leveraging its 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, emphasised that a close working relationship with the 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,” Burger said. “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.

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 cu.m/h up to 2,000 cu.m/h.

Total Eren, Chariot and Tharisa to build solar PV plant at PGM mine

Total Eren, a renewable energy independent power producer, and Chariot, an Africa-focused transitional energy company, have signed a Memorandum of Understanding (MoU) with Tharisa plc to develop, finance, construct, own, operate and maintain a solar photovoltaic project for the supply of electricity to the Tharisa PGM mine, in the North West province, South Africa.

The solar PV project is initially anticipated to be 40 MW peak with demand expected to increase over the life of the Tharisa Mine. This MoU is the first step towards implementation of the project and signing of a long-term Power Purchase Agreement for the supply of electricity on a take-or-pay basis, the companies said.

Fabienne Demol, Executive Vice-President & Global Head of Business Development of Total Eren, said: “We are very pleased to be entering into this MoU with Tharisa. Through our partnership with Chariot, we are keen to assist mining companies in Africa to reduce their carbon intensity and energy costs, via implementing renewable power solutions into their operations. We are eager to bring our global expertise in solar generation to Tharisa mine and we look forward to delivering further renewable projects for our mining customers in Africa and worldwide.”

Benoit Garrivier, Chariot Transitional Power CEO, added: “This is a great outcome for Chariot’s Transitional Power division and demonstrates the financial and sustainable benefits that our offering can bring to mining companies operating in Africa. The Tharisa team are very forward looking and understand that the addition of a solar PV project at their mine in South Africa will bring significant benefits to the business. Together with Total Eren, we are excited to start working on the financing and development of the project and we will update the market further on this and other opportunities that we are progressing in due course.”

Tebogo Matsimela, Head of ESG at Tharisa, said: “Tharisa plays a significant part in the global energy transition movement, and we are committed to producing these key metals in a sustainable manner. The solar power solution provided by Total Eren is but one of several steps we are taking to ensure our flagship Tharisa Mine, which has a life of mine of over 50 years, has a reduced carbon footprint.

“Our goal is to reduce our carbon emissions by 30% by 2030 and ultimately become net carbon neutral by 2050.”

Tharisa Minerals produces PGM concentrate and metallurgical- and specialty-grade chrome concentrates from a shallow open-pit mine near Rustenburg, North West province. The Genesis and Voyager plants at the operation have a combined nameplate capacity of 4.8 Mt/y of run of mine.

BME’s achieves another record-breaking blast with AXXIS Titanium electronic detonators

Another record-breaking blast has been notched up by Omnia Group company BME using its latest generation AXXIS Titanium™ electronic detonation system.

The blast of 5,209 detonators was conducted recently at a chrome mine in South Africa’s North West province, according to Tinus Brits, BME’s Global Product Manager – AXXIS. Brits highlighted how the enhanced features of AXXIS Titanium allows mines to respond quickly and easily to raised production demands.

“While a record blast is always an achievement to be celebrated, this was a standard production blast requiring nothing different or extra from the mine,” he said. “The ease-of-use of AXXIS Titanium, the speed at which blasts can be prepared, and its rapid testing features make this possible.”

The dual-voltage basis of the new system means that detonators can be tested while they are logged in, with the logging and testing conducted as a single function. As a result, this record blast could be primed, charged, tied-up, logged, tested and programmed in just two days.

“With AXXIS Titanium, the logger does everything for you,” Brits said. Multiple loggers were used on the blast, with each operator logging a portion of the blast to speed up the process; the log files were then seamlessly combined.

By consuming less energy, AXXIS Titanium allows up to 1,000 detonators to be initiated by each blasting box – reducing the amount of equipment that is needed on site.

“This helps improve the reliability of blasts, as there are fewer items of equipment to communicate with each other,” Brits said. “These high levels of reliability ensure a quality blast with no misfires, even in single-prime blasts – where there is just one detonator per hole – as was the case in this record blast.”

He also emphasised the intuitive fault-finding capacity of the AXXIS Titanium system, which identifies those detonators which have not been logged onto the harness wire. The operator is informed precisely where the relevant detonator is to be found, so it can be quickly logged.

“It also solves the problem of ‘intruders’ – those detonators that were accidentally missed during the logging process,” Brits said. “Again, the operator can speedily fix this issue wherever it occurs, ensuring that there are no misfires in the blast.”

The design of the AXXIS Titanium connector is another important factor, allowing blasters to log and test detonators without the need to open the connector. The gel in the connector that ensures a good seal, therefore, is not disturbed during testing and logging.

“It only gets opened up once you connect it to the surface wire, which is why the sealing of our connectors is so good – eradicating resistance or leakage on the block,” Brits said.

Tharisa kicks off Vulcan ultra-fine chrome recovery and beneficiation plant commissioning

Tharisa, the platinum group metals (PGMs) and chrome co-producer, has announced that cold commissioning of its Vulcan ultra-fine chrome recovery and beneficiation plant has commenced.

The timetable to completion of the new $55 million plant remains firmly on track with initial saleable production due before year end, it says.

Once fully commissioned, the plant is expected to see Tharisa Mine, in South Africa, materially increase its chrome recoveries from circa-62% to circa-82% resulting in increased chrome production of some 20% at low incremental unit operating costs.

The plant, which will process live tailings produced by the independent Voyager (pictured) and Genesis plants, will ensure further beneficiation of the company’s chrome production at the Tharisa Mine, while reducing unit output of carbon emissions, aligned with Tharisa’s recently announced decarbonisation plan, the company says.

The Vulcan plant has a nameplate capacity of 340,000 t/mth of tailings and involves “proprietary ground-breaking use of existing technologies in fine chrome recovery”, the company says. The board initially signed off its construction in 2019, appointing Wood as the engineering, procurement and construction management contractor in the process, with hot commissioning targeted for the December quarter of 2020. This timeline was impacted by COVID-19.

Some final elements of the construction process remain to be completed, yet Tharisa’s engineering team has commenced cold commissioning, with comprehensive testing of the entire circuit, to be completed prior to chrome tailings material entering the plant. Of the total capital expenditure, over 90% was procured locally in South Africa, with up to 1,000 contractors locally sourced and over 100 new permanent jobs created.

Vulcan is, Tharisa says, the first large-scale plant to produce chrome concentrates from chrome ultra-fines. The concept of Vulcan was developed by Arxo Metals Proprietary Limited, a wholly owned subsidiary of the company and housing Tharisa’s in-house R&D team, to extract the ultra-fine chrome from tailings.

With Tharisa Mine near Rustenburg having a 14-year open-pit life remaining, and a further 40 years underground, Vulcan will ensure maximum value extraction and beneficiation of the chrome ore, Tharisa says. The Tharisa Mine has 860 Mt in mineral resource containing 172 Mt in contained Cr2O3 and 42.8 Moz platinum group metals.

Internally funded by Tharisa, Vulcan recommenced construction in October 2020 after the lifting of restrictions by the South African government during the height of the first wave of the COVID-19 pandemic.

Phoevos Pouroulis, CEO of Tharisa, says: “Commissioning of the Vulcan plant perfectly exemplifies two Tharisa philosophies: challenging convention through innovation and delivering on our promise of maximising value through beneficiation of every cube mined.

“Vulcan provides the company with the ability to further beneficiate our product whilst staying on track to meet our decarbonisation targets, thanks to the dedicated work from Arxo Metals, that has not only delivered the Vulcan process but has also delivered further beneficiation opportunities, including metal alloys and PGM products using non-conventional methodologies.

“Vulcan is an important part of our sustainable growth strategy and ensures that Tharisa continues to drive sustainable returns for all of our stakeholders, while simultaneously pushing us even lower on the cost curve.”

Kazchrome achieves chrome tailings flotation breakthrough

Engineers at the Donskoy Ore Mining and Processing Plant of JSC TNC Kazchrome, in Kazakhstan, have successfully completed trials of a first-of-its-kind industrial flotation technology to increase the enrichment of chrome oxide-bearing tailings, Eurasian Resources Group reports.

Kazchrome, the world’s largest high-carbon ferrochrome producer by chrome content with a total resource base of over 200 Mt of chrome ore, is owned by ERG.

The novel technology is part of the group’s R&D efforts to maximise chromite concentrate output and reduce the site’s environmental footprint, the company reports, with the process yielding the recovery of over 55% of chrome oxide and conforming to the applicable requirements for concentrate used in ferrochrome smelting.

As a result of these trials, the flotation technology will be used to construct a new facility to process over 10 Mt of chrome oxide-bearing tailings with a planned annual capacity of 1.7 Mt for 450,000 t/y of chrome concentrate, ERG says.

Benedikt Sobotka, CEO of Eurasian Resources Group, said: “This pioneering technology is a major milestone on our path towards ensuring sustainable and low-cost chromite concentrate supply for our operations in Kazakhstan, and is part of the group’s broader strategy to reinforce our leading position in the global ferrochrome market.”

Sergey Opanasenko, Chairman of the Management Board of ERG R&D Centre, added: “We are very pleased with the results of the flotation trials, particularly considering the complex mineralogy and physical characteristics of our ores. Building on this success, we look forward to working on incorporating this technology into the design of our new tailings processing facility.”

Sedibelo Platinum to expand PPM operations and leverage Kell Technology

Sedibelo Platinum Mines has announced plans to expand its Pilanesberg Platinum Mines (PPM) operation on South Africa’s Bushveld Complex, as well as construct a 110,000 t/y beneficiation plant at PPM employing Kell Technology.

The company plans to mine the three contiguous deposits of Sedibelo Central, Magazynskraal and Kruidfontein – known as the Triple Crown properties – as part of the expansion. These three come with an estimated resource base in excess of 60 Moz of 4PGE.

The predominantly shallow deposits will enable safe and sustainable mining activities for potentially more than 60 years, according to the company. The approved expansion will be funded through Sedibelo’s existing cash resources and future cash flow, with first ounces from Triple Crown expected to be extracted in 2023.

The Triple Crown expansion will be mined simultaneously with ore from the existing open-pit UG2 and Merensky operation, using two separate decline shaft systems, the company said.

The existing PPM concentrator plant has the capacity to be used to process the Triple Crown ore as well as ore from the open pits. With minimal reconfiguration, the Triple Crown UG2 and Merensky ore will be blended and processed through the existing Merensky plant, thereby reducing capital expenditure as well as lowering operating cost significantly, it said.

Speaking of the 110,000 t beneficiation plant, Sedibelo said Kell Technology reduces energy consumption by some 82% with the associated significant reduction in carbon emissions, also improving recoveries and lowering operating costs.

“Benefitting from being robust in operation, Kell is unconstrained by concentrate grade, is insensitive to chrome levels as well as being resistant to other impurities,” it explained. “Hence, using Kell will improve the economic return of the Triple Crown expansion and is an integral part of Sedibelo’s future development.”

As applied to treatment of PGM concentrates, the Kell Process comprises four main unit operations (pressure oxidation, atmospheric leach, heat treatment and chlorination), all of which are conventional and in commercial use in the minerals and metals industry.

Sedibelo shares an interest in Kell South Africa with the Industrial Development Corp and Founder Keith Liddell, through Lifezone.

Arne H Frandsen, Chairman of Sedibelo, said: “Today is a significant day in Sedibelo’s history. We are opening our next door 60 Moz Triple Crown deposit, thereby securing the future of Sedibelo for many decades to come. The construction of our Kell plant will allow us to produce metal and lower our cost profile further. Equally important, it will reduce our carbon footprint and water usage significantly.

“We trust our environmentally friendly platinum group metals will become an important part of future electrification and the ‘green revolution’ used in fuel-cells around the world.”

Keith Liddell, Founder of Kell and CEO of Lifezone, said: “I developed Kell Technology as a cost-efficient alternative to the conventional smelting of PGMs. We are excited to now proceed with the construction of the Kell plant at PPM. The benefit for Sedibelo and the industry will be significant; delivering beneficiation, energy and cost advantages as well as a reduction in CO2 and SO2 emissions.”

TOMRA connects ore sorters to the cloud with TOMRA Insight

After a successful launch in its recycling division, TOMRA is rolling out its cloud-based data platform, TOMRA Insight, to mining customers.

TOMRA Insight enables sorting machine users to improve operational efficiencies through a subscription-based service that turns these machines into connected devices for the generation of valuable process data.

Following a successful launch last year by TOMRA Sorting Recycling, TOMRA is now also being made available to customers of TOMRA Mining and TOMRA Food. For all three industries, the platform is enhanced by new features and functionalities that make TOMRA Insight even more valuable than when it was launched to recyclers in March 2019.

The data from TOMRA Insight is gathered in near real time, stored securely in the cloud, and can be accessed from anywhere and across plants via a web portal available for desktop and mobile devices, according to the company.

Felix Flemming, Vice President and Head of Digital at TOMRA Sorting, said: “By capturing and using valuable data, TOMRA Insight is transforming sorting from an operational process into a strategic management tool. This tool is constantly becoming more powerful as we continuously develop it in response to customers’ needs and priorities. New functionalities and features are released every three weeks – a routine during which TOMRA works closely with customers in pursuit of shared objectives.”

Data captured by TOMRA Insight provides valuable performance metrics that help businesses optimise machine performance.

Operating costs are reduced by simplifying spare part ordering and offering flexible access to data and documentation, according to the company. Downtime is reduced by monitoring machine health and performance in near real time, identifying gaps in production and analysing potential root causes. This allows management to move to predictive and condition-based maintenance, preventing unscheduled machine shutdowns.

Throughput, meanwhile, is maximised by evaluating variations and optimising sorting equipment, accordingly. Sorting to target quality is enhanced by having accurate material composition data to enable decisions to be based on more detailed information.

For the mining and mineral processing industries, TOMRA Insight’s ability to collect detailed data from TOMRA’s sorting machines means that previously hidden information can lead to improvements in efficiencies and profitability.

Data captured by TOMRA Insight is analysed on behalf of customers by TOMRA Mining engineers, and key findings shared in confidential reports supplied to customers on a monthly basis. This arrangement has the advantage of combining objective statistical analysis with the interpretive skills of a service team familiar with the customer’s unique challenges, TOMRA says.

“TOMRA Insight’s data-gathering helps mineral processors in near real time and in retrospect,” the company said. “Machine operators are empowered to take prompt action in response to changes in material composition on the line and managers are empowered to make operational and business decisions based on more complete information.”

Comparisons between multiple sites or lines can now be made more accurately and difficult-to-reach processing operations can be remotely monitored from more convenient locations, the company said. This functionality is especially useful in the face of widespread travel restrictions related to COVID-19.

One early, pre-launch user of TOMRA Insight is the Black chrome mine in South Africa (pictured above), one of two mining projects that form the basis of the Sail Group’s plans for long-term sustainable chrome production. Since TOMRA Insight was connected to sorting machines here at the start of 2020, the data platform has convincingly proven its effectiveness, TOMRA said. Among the gains made so far are improvements in process monitoring and streamlining, more efficient line-feeding and machine running times, and reduced downtime.

Albert du Preez, Senior Vice President and Head of TOMRA Mining, said: “By accessing information, TOMRA Insight is unlocking new opportunities. Mineral processors can now move from making decisions based on experience and local observations to decisions based on experience and hard facts. This means TOMRA Insight can help reduce waste rock and downstream processing costs, enabling processors to earn more dollars per tonne.”

To build on these benefits, TOMRA Mining is working closely with customers to continuously develop TOMRA Insight. The future will bring the addition of more features and functionalities, which customers will automatically receive as part of their Service Level Agreement.

Multotec solution scrubs up well at Ekapa Minerals diamond plant

A revolutionary new concept in fines scrubbing is proving to be a game changer for Ekapa Minerals at its Combined Treatment Plant (CTP) in Kimberley, South Africa.

The innovation, developed by Multotec Wear Linings, is processing both virgin underground kimberlite as well as tailings for retreatment at the CTP. The solution is effectively a pulping chute that scrubs and washes the re-crushed product after it has passed through the high pressure grinding rolls (HPGR) inter-particle tertiary crushing circuit.

The important advantage here, according to Multotec Wear Linings Projects Sales Manager, John Britton, is that it performs the scrubbing action faster and more efficiently than a traditional rotary scrubber would, and at much lower cost.

Multotec commissioned two of these pulping chutes at Ekapa Minerals in late 2019, where they have been operating consistently and in line with expectations. With the use of patented wave generators, the pulping chute uses the gravitational energy from the slurry flow to create a constant turbulent mixing action that releases the mud, clay and slime sticking to the kimberlite particles.

According to Ekapa Minerals CEO, Jahn Hohne, the pulping chutes are a welcome contribution to the company’s cost saving efforts, and a clear demonstration of Multotec’s expertise in developing value-adding solutions in the mining sector.

“The dual chute pulping plant is ideally suited to de-conglomerating the HPGR cake product and is exceeding expectations in efficiency and effectiveness at over 600 t/h, which is a major relief on the existing overloaded pair of CTP scrubbers,” he said. “The net result is a meaningful increase of up to 20% throughput capacity of the entire processing plant which substantially improves the economy of scale of CTP, feeding directly to the bottom line.”

Britton highlighted the efficiency of the system, which is able to aggressively scrub the material in just three to four seconds as it passes through the chute. This represents just a fraction of the usual retention time in a rotary scrubber, which is three to four minutes, according to the company. He also emphasises the drastic reduction in running cost which the pulping chute achieves.

“From our experience of plant layouts and flow diagrams, it is clear that fines scrubbers are significant contributors to a plant’s capital, operating and maintenance costs,” Britton said. “Scrubbers are equipped with large drives with gears and gearboxes to rotate the drum. They are high consumers of power and require mechanical component maintenance which means higher operating costs.”

Substantial structures and supports are also needed for the scrubber and its drive mechanisms. In designing the pulping chute, Multotec sought a simplified solution, Britton says. In addition to improving scrubbing efficiency, the objective included reducing the cost of replacing scrubber liners and the downtime that this demanded. The cost of replacing the steel shell of a scrubber – which is constantly subject to stress, wear and fatigue – was another cost to be considered.

“The pulping chute, by contrast, is a stationery and much simplified innovation, focused on the scrubbing of fines less than 32 mm in size,” the company said. “Slurry deflectors located at the top end of the scrubbing chute direct at least part of the slurry away from the scrubbing chute floor. This curls into an arched form which flows backwards into the approaching flow of slurry, creating the turbulent scrubbing effect.”

Britton said: “We custom-design the chutes to suit the application and can increase chute capacity to up to 800 t/h. This is achieved with no moving parts, bearings, hydraulic packs or girth gears; the only power required is to supply material and water to the receiving chute. These actions are also required to feed the scrubber, then gravity takes over and provides the required energy.”

Maintenance is also streamlined by designing the chute in segments. Should one segment be wearing more than others, it can be quickly removed and replaced – putting the chute back into operation while the original segment is refurbished as a spare.

Britton says the pulping chute has drawn interest from other diamond producers in southern Africa, Australia and Canada. It can also be applied in commodity sectors such as coal, platinum, chrome, iron ore and mineral sands.

TOMRA’s XRT ore sorting aids recoveries, costs at South Africa chrome mine

One of TOMRA’s X-ray Transmission (XRT) sensor-based ore sorters is helping improve recoveries and lower costs at a South Africa chrome operation.

As South Africa chrome mining operations have increased production in the face of rising demand from stainless steel buyers, the cost of using traditional methods for separating low-grade chromite material, such as dense media separation (DMS), cyclones and spirals, has increased. XRT ore sorting, an established technology in physical separation that has proved extremely effective in mining operations for a variety of minerals, including chrome, is another pre-concentration route they are looking into.

“Its benefits are significant: less complexity in the process, considerably lower costs, higher productivity and profitability – and the added advantage of a lower environmental impact,” TOMRA, a supplier of XRT solutions, said.

The X-ray sensor accurately establishes the density of each particle in the feed, and high-speed pneumatic ejectors separate ore with high chromite content from barren or low-grade ore at throughputs between 60-200 t/h. “The resulting output is a high-grade product that is ready to sell, with no need for additional comminution,” the company said. “It is a dry process that requires no water or reagents, and is frugal in its energy consumption, resulting in a fraction of the capital expenditure and running costs of traditional methods, as well as a smaller footprint.”

Engineering and project management company P2E Consulting has first-hand experience of the advantages of TOMRA’s XRT technology in sorting chrome ore at Eastern Chrome mines, in South Africa. It was looking for a solution to improve the efficiency of the sorting plant and turned to TOMRA.

“We have installed TOMRA sorters on diamond and copper plants in the past and we believe their technology is ahead of their competitors,” Craig Meadway, Business Development Executive of P2E Consulting, said.

P2E Consulting commissioned a TOMRA COM XRT 2.0 sorter to replace an existing drum DMS plant.

“The mine used the DMS plant to produce saleable small lumpy product from the mine’s LG6 Chromite run of mine and dumps at a minimum grade of 38%, but it was very inefficient,” Meadway explains. “The TOMRA XRT sorter has resolved this issue. It is used to upgrade under value material with a head grade of 20-28%, to produce a saleable product at a minimum grade of 38% Cr2O3. It does this efficiently and at a low cost of production.”

The TOMRA COM XRT 2.0 sorter has exceeded Meadway’s expectations, with grades being achieved in excess of 40% Cr2O3 and mass recoveries of 25-30% from scalped waste resulting in chrome-in-tails as low as 12%.

“No other technology has given us such a high recovery rate. Not only that, with TOMRA’s XRT there was no water usage at all, and we didn’t need to spend on expensive reagents, so that we are producing small lumpy product for approximately 50% of the cost compared to a DMS plant,” he said.

The environmental benefits of TOMRA’s XRT solution were also an important factor in P2E Consulting’s choice of technology. “We are looking to introduce greener technologies into the mining industry. The fact that no water or chemicals are used is a major advantage,” Meadway said. “Also, South Africa has major power limitations, and the lower energy consumption when compared to DMS is a huge driving force.”

The ease of operation of TOMRA’s XRT sorters proved to be a further advantage: “It is very easy to use: once the sorter and feed system control philosophy is set up correctly, the plant runs with very little input from the operators,” Meadway said.

TOMRA’s collaborative approach and all-round support was also an important factor in P2E Consulting’s decision to turn to them for this project, according to Meadway.

“We knew from our experience in previous projects that the support from TOMRA is very good, and with the installation of this machine in a relatively new application, it was excellent,” he said. “The local team has bent over backwards to help us make this happen.”

Multotec ready for the mineral processing test

Mineral processing specialist, Multotec used a recent media visit to talk up the testing facilities at the heart of its Technology Division.

The South Africa-based company can carry out a range of testwork with its specialised equipment in Spartan, Gauteng, according to Multotec Technology Manager, Faan Bornman.

“Much of our testwork comes from customers who are in the early stages of project development,” Bornman says.

“They need to understand more about how their minerals or material will separate under given conditions. Often there is not a mathematical model that can predict accurately what they can expect.”

Testwork can reduce project risk significantly, providing a solid foundation for the subsequent design and optimisation of process facilities, Multotec says, with Bornman noting that physical testwork is usually the best way of finding out how particles will behave in a process plant.

The equipment available to Multotec customers includes laboratory-scale wet high-intensity magnetic separators, cyclone rigs, filtration equipment, centrifuges, spiral rigs and a screening research rig. There is even capacity to test water purification methods on mine effluent.

“Extensive test work is especially relevant when a customer is wanting to mine and treat less traditional minerals like lithium or graphite,” Bornman says. “As demand grows for commodities like these, we have had customers bring samples to test how our equipment would perform. In these tests, we trial various methodologies and scientifically record and compare the results.”

The R&D laboratory prepares samples and conducts particle size analysis using equipment such as pressure filters, drying ovens, sieves, shakers, sizers and separating funnels. When chemical analysis is required, samples are sent to outside laboratories.

Bornman said his division also receives enquiries from existing customers when they face challenges: “We research the application of different methodologies to customer material, often leading to the development of a new product or improvements to our existing products,” he said.

“In addition to providing a solution for the customer, we are also able to contribute to the efficiency of the industry as a whole, with an updated and commercialised product.”

Screening

When it comes to tests on mineral screening, a test rig – located at Multotec’s Spartan headquarters – delivers two primary benefits, according to Chris Oldewage, Technology Manager at Multotec Manufacturing. First, it facilitates the in-house development process of screening media products. Second, it allows screening media to be tested against customer requirements to ensure the right solution is delivered.

“The ongoing research and development behind our screening media products give the industry opportunities to optimise efficiencies and recoveries,” Oldewage says. “However, changing anything on a plant brings risk of unexpected downtime. Our screening test rig can considerably reduce operational risks by proving any changes before they are implemented on site.”

In the controlled environment provided by the screening test rig, customers can view the actual performance of screening media products with material from their mining operations, Multotec says, with the company’s testing protocols generating the data necessary for detailed process analysis. This facilitates well-informed subsequent decisions, the company said.

The screening rig is made up of three test platforms: a vibrating screen, a sieve bend and a static drain screen platform. The vibrating screen can conduct classification tests, wet and dry dewatering tests, product development tests and plant screen simulations. The static drain screen and sieve bend screening test platforms are wet classification, drainage and dewatering tests.

Multotec Process Engineer, PJ Pieters, said accurate scaling of a customer’s on-mine process is vital for achieving representative and relevant test results.

“We gather a range of key data from customers on our test work questionnaire,” Pieters said. “This includes their material tonnages, volumes of water, screen sizes in operation and aperture sizes on panels among other information.”

This ensures sample sizes are representative and the tests accurately reflect what is taking place in the mine’s processes. Tests, meanwhile, are conducted in triplicate runs to ensure a sound scientific basis for the findings.

Oldewage said: “By removing the risk that mines face in trying new solutions, our testing capability smooths the way for valuable innovation to improve screening performance.”

The screening test facility at Multotec also includes a small Lucotec screen and a small wedgewire trommel screen, both for small-scale verification test work.

Cyclones

Multotec’s large scale cyclone rig, meanwhile, can test the performance of a range of cyclone sizes, up to 450 mm diameter. Tests related to classification, desliming and dewatering, as well as dense medium separation using density tracers, can be conducted.

Among the benefits to customers is the ability to test large volumes of samples, as the rig includes a 1,750 litre sump and a 6/4 pump, Multotec said. Flexibility is provided by a variable speed drive connected to the pump, to vary the flow rates as required by the cyclone size.

Dry samples usually need to be blended before testing, and wet samples may need to be dried before blending. The resulting samples from the test must also be scientifically prepared for particle size and chemical analysis. The precision at each stage is vital, as bulk samples as large as 200 kg may need to be reduced to as little as 100 g.

The rig’s infrastructure also includes two Multotec vezin samplers, which are compliant with the highest design standards to provide reliable samples, according to Multotec. “These help to minimise the common errors of manual sampling and ensure that the integrity of the sample is retained,” the company says.

In addition to using the test rig to analyses the customer’s process flowsheet – with Multotec engineers identifying where its range of classification and other products can add value – the company also uses the cyclone test rig for its own product development.

“This on-going process has resulted in a range of cyclones that are lighter, more cost effective, environmentally-friendly and energy efficient,” the company said. “They all contribute to helping customers lower their cost per tonne in a low footprint, sustainable plant operation.”

Spirals

Multotec says its spiral test rig has been adapted in response to the industry’s need to re-treat chrome dumps and upgrade ultra-fine chrome.

Again, located at the company’s headquarters in Spartan, the rig allows eight to 10 different spirals to be erected at a time.

Jeantelle Rust, R&D Engineer at Multotec Process Equipment, said: “With the drive to process tailings in the chrome sector, we have been running tests on a more compressed spiral with a reduced pitch. This reduces the velocity of the very fine particles.”

This configuration works particularly well when dealing with fine material, hence its application in tailings, Rust said. The spiral could offer a cost-efficient way of separating ultra-fine chrome material and recovering valuable product, according to the company.

Rust said: “Such a solution presents an attractive commercial proposition to industry and will also address environmental concerns presented by tailings dumps.”

Using a “mouth-organ product box”, the material being tested on the spiral rig is split into eight product fractions, not just the usual three for product, middlings and tailings. This helps optimise the mass balance for reporting purposes, according to the company.

The spiral test rig has also been used to evolve designs that deal with coarser material, Multotec said. “Customers were looking for a solution to the ‘beaching’ of coarse coal product on the spiral’s surface, for instance,” it explained.

Rust said: “We were able to modify the angles and diameter of the trough to address this challenge. Our ability to make small adjustments to the equipment, and to test material repeatedly at full scale, is the key to finding practical solutions.”

Multotec has also conducted research for producers of mineral sands where head grades were steadily dropping. This necessitated the treatment of larger tonnages, requiring higher capacity spirals.

“Space constraints on the customer’s site meant that adding spirals to their process was not an option,” Rust said.

“Wider spirals were thus tested for higher throughput, with different angles to minimise losses.”