Three-dimensional printing – otherwise known as ‘additive manufacturing’ – gives minerals processing equipment solutions leader Multotec a new string to its bow, enabling rapid and effective technology innovation for optimal customer benefit.

While computer-aided design (CAD) software has, for many years, allowed manufacturers to test new or improved products by simulating their behaviour on-screen, there comes a point at which it is quicker and easier to build a prototype of the product to elicit user feedback on the design and its functionality.

Multotec invested in 3D printing technology to improve its efficiency in creating and testing these prototypes, thereby improving the speed to market of its newly developed products.
There are already several examples of how successfully the group has done this, both here in South Africa and for its customers abroad.

In one case, a Multotec Canada customer had a specific requirement for its unique spiral application and wanted the concentrate splitter to cut the flow in a specific location. To do this, a spiral flow diverter was designed that would attach to the spiral’s working surface in front of the product box.
A prototype unit was 3D-printed in-house, and trial-tested and refined in South Africa.

To minimise the lead time, a digital model of the prototype was sent to Multotec Canada, who was able to have the item 3D-printed in Canada within 48 hours – showing how rapid prototyping could create a customer-specific solution in just a short timeframe, almost anywhere in the world.

Similar success was achieved in developing a quick-release spigot holder and coupling for a cyclone, following feedback received from customers. The customers had noted that the process of changing out the spigots was taking a considerable amount of time and effort, as all the bolts to the spigot holder had to be removed to replace the spigot.

The solution pursued allowed the spigot holder to be screwed apart rather than unbolted; the prototype was 3D-printed in-house by Multotec and presented to the cyclones division – giving experts the ability to see and feel the product before any investment in tooling was made.

The screw spigot holder and coupling are now being injection-moulded, which has further reduced the component’s mass, as well as the cost and time it takes to manufacture.

In another example, a Multotec customer requested a solution to completely block material flow from the sliding splitters to the concentrate gully of their spirals.
After a solution was designed, 3D-printed and successfully tested, a silicon rubber mould could be produced from the 3D-printed component. This mould was then used for casting polyurethane and producing a final product which met the customer’s needs, speeding up the time to market and cost of production.

Multotec’s 3D printing capabilities have also allowed the company to study the concentrate flow in a spiral, by using a 3D-printed spiral off-take prototype that fits to the profile and slope of the spiral. Research is underway to ascertain what the different grades are that exist within the concentrate section of the flow, so that equipment and processes can be continually optimised for customers – thereby enhancing plant efficiency and the overall cost per ton.


Leveraging digital technologies in its range of mineral processing equipment will again allow Multotec to display new product developments at Electra Mining Africa that optimise recoveries and reduce cost of ownership for mineral processing plants.

“Technologies such as smart panels and 360˚ virtual reality video can make a valuable contribution to pioneer greater efficiencies, by helping predict and schedule equipment maintenance,” says Multotec group CEO Thomas Holtz. “This assists planning at plant level and means less unexpected downtime as a result of equipment failure; every step we can take on this innovation journey gets us closer to a more sustainable mining sector.”

Inspired by the philosophy ‘think global and act local’, Multotec can draw from its experience around the world to feed into its ongoing research and development programme that continuously improves its wide range of offerings from screen media and wear solutions, to solid-liquid separation and mill linings.

“Retaining the technological edge is one important way that South Africa can sustain and grow its local manufacturing capability,” says Holtz. “As a Level 4 B-BBEE company with a 26% black shareholding, we are fully supportive of the emphasis that the Mining Charter places on local content, and especially about the plans for formal verification of local content.”

According to the Manufacturing Circle – in which Multotec is an active member – the country’s percentage of local manufacture as a percentage of GDP has dropped from 24% in 1994 to just 12% today, with the difference going to imported products.

“If we want to drive a local manufacturing agenda and create jobs in the manufacturing sector, we must have an effective way of verifying local content in manufacturing activity,” says Holtz.

He says the company is already participating in the engagement process with the South African Bureau of Standards about how such a verification system could be designed and implemented, as an auditing authority, such as the SABS, would be required to make the system work.

“Equipped with the right framework and incentives, the mining sector could improve its already substantial contribution to stimulating local manufacture and technology development,” he says.

With 45 years of specialised experience in its field, Multotec also provides skills development through its in-house training facility, constantly raising the expertise in its extensive network of branches around South Africa and the rest of Africa.
Its innovation even goes beyond product development, to evolving new service models – such as its ‘cents per tonne’ model in which customers pay a monthly invoice based on process tonnages to maintain their process equipment.

Multotec can be found in Hall 6A22 and outside OSP20.


Multotec hydrocyclones and spiral concentrators are being applied in Europe to address the growing demand for the rehabilitation of contaminated land. The application of the solution is via Multotec’s European agent of 25 years’ standing, Bernd Bohle, Dipl. –Ing of Bohle Ing. Beratung.

According to Bohle, pollution and soil contamination have become leading environmental issues for most European countries in recent years, with well over 300,000 sites thought to be affected by this problem.

In a recent application, Multotec commissioned its equipment in a modern soil washing plant in the Italian speaking part of Switzerland. This also involved the training of staff in both German and Italian, through collaboration with Bohle Ing. Beratung and Italian partner SST/4Sep sagl., Manual Nava.

“Treatment methods in Europe vary from the conventional engineering techniques to the use of alternative technologies for decontamination that use physical, chemical and biological reactions,” says Bohle. “These latter technologies – such as biological remediation, thermal treatment, vitrification, vacuum extraction, and soil washing – are growing in demand.”

He highlights that many of these technologies, especially soil washing, have been successfully demonstrated and applied on an industrial scale in countries like Germany, Switzerland and the Netherlands.

“The largest markets – accounting for over 50% of the European Union total – are Germany and Switzerland,” he says. “The Netherlands and the UK are also significant, while the French and Italian markets are expected to grow rapidly by the end of the decade.”

The pressure is coming from more stringent regulations, he explains, which trigger the need for land decontamination when there is any planned development of a site, or where the spread of contamination is detected.

“Most of the soil cleaning techniques require on-site soil washing, where the material is treated to separate the contaminants from the soil before further naturalisation can take place,” he says.

It is here that the Multotec cyclones and spiral concentrators have come into their own. In particular, the spirals have been steadily incorporated into the process, for the separation of light and heavy fractions.

“In many instances, spills of contaminated hydrocarbons in industrial areas have been adsorbed over a period of time into the carboniferous phases of the soil. This is often a combination of coal, lignite, charcoal, tar and organic detritus,” says Bohle. “In such cases, removal of this material by physical means can allow the separation of the contaminated hydrocarbon fraction into a low density product for further treatment or disposal.”

In these applications, the use of spiral concentrators, with their flat angles as in large diameter coal spirals, can remove the low density material from the soil bulk. Other important applications include the removal of metallic matter, oxides, sulphides, carbonates and slags from contaminated soils in industrial sites such as former automobile scrapyards. Here, heavy mineral spirals with their pitch angles of 21 degrees can remove metallic matter from the soil.

At the BSH-TIB Mezzovico soil washing plant in Switzerland, Multotec’s large diameter coal spirals and its heavy mineral spirals are supporting the decontamination process at a rate of up to 70 tonnes per hour of solids.

The installation allows between 27 tonnes and 40 tonnes per hour of pre-screened material sized from zero to 1,8 mm to be pumped to a VV350-15-1 stacker cyclone with a capacity of up to 170 m3 per hour. The re-diluted underflow is fed by gravity to a spiral bank for lights decontamination. The heavy sand product is then pumped to a stacker cyclone of the same specification, with the re-diluted underflow reporting to a spiral bank for heavy particle removal.


Leading mineral process company, Multotec Process Equipment, will be providing a continuous ion exchange (Clean-iX®) metals processing scavenging equipment to a customer in the Democratic Republic of Congo.

The equipment, using Clean-iX® ion exchange technology from Melbourne-based metals recovery and industrial water treatment specialists Clean TeQ, will treat up to 20 million litres a day of a raffinate stream, removing contaminant metals and improving the quality and environmental rank of the raffinate before it is processed further.

The technology is built on the foundations of batch ion exchange, a process that has been used in the industry for over 50 years. The Clean-iX® process allows the extraction of metals from clarified leach liquors using a ‘moving packed bed’ column, maximising adsorption; this method of extraction has higher efficiency than conventional technologies.

As a leading provider of high-quality mineral processing equipment and solutions to the mining, mineral processing, petrochemical and power generation industries, Multotec has an exclusive technology distribution agreement with Clean TeQ for the African continent.

Carien Spagnuolo, senior process engineer at Multotec Process Equipment, says the group leverages its extensive sales and service network in African countries to bring customers leading edge technologies from around the world, especially for niche applications or difficult to treat waters.

“The DRC contract confirms the rapidly increasing global interest in the application of continuous ion exchange technology for metallurgical scavenging and water purification,” she says. “The installation is expected to offer another valuable reference for the efficacy and cost effectiveness of the process, for which there is a large potential market.”

In metals recovery and purification, Multotec is able to draw on Clean TeQ’s Clean-iX® technology. There is also a suite of water purification technology from Clean TeQ that includes Continuous Ionic Filtration (CIF®), DeSALx® for desalination and sulphate reduction, and HiROx® for high recovery reverse osmosis.

The DRC project is the second contract awarded in the past 12 months in which Multotec has applied Clean TeQ’s technology offering. Multotec is also currently implementing a proprietary continuous ionic filtration wastewater treatment solution at a mineral processing plant in the Middle East. Multotec was the principal bidder with overall responsibility for delivering the complex wastewater management and effluent treatment systems for the pyro-metallurgical mineral processing facility.


The correct time to change mill liners is when the efficiency of the mill drops and not when you think the lining is completely worn. Spike Taylor, managing director of Multotec Rubber, explains that the efficiency of the mill liner relates directly to recovery efficiency of the downstream equipment, and that plant operators need to adopt a far more proactive approach in this regard.

“A further ramification of waiting too long to change out the mill lining is that the fresh feed rate will decrease significantly because of the higher recirculating load, and this will have an obvious impact on production throughput in a plant,” Taylor says.

One of the major costs associated with operating a minerals processing plant is the cost of power or kW.hr/t, and this is significant because when the efficiency of the closed circuit mill is reduced it means that the material is essentially being treated more than once. This is a major additional cost factor, but often one that is not apparent.

Sam Hearn, global sales and business development manager at Multotec Rubber says that often when speaking to plant operators, a hurdle that needs to be jumped is the misconception that the mill liner is an expensive purchase.

“Once we have engaged with the plant engineers and drawn to their attention that the liners only cost between 10 to 20% of the operating cost of a mill, and that the cost of power is far greater we have their attention,” Hearn says. Power is a monthly expenditure for a plant and in most cases is not directly allocated to the mill’s operating costs, yet power accounts for about 60% of the total operating cost for that mill.

Hearn says that if it is accepted that the power cost is 60% and the liner cost is 10%, then the balance of the mill’s operating costs can be attributed to the grinding media. “This is an area which can be adversely affected by liner profile and charge trajectory so Multotec takes special care to ensure the design is correct,” he explains.

Worn liners allow more slippage of the charge and this results in an acceleration of the wear rate which can lead to the predicted life not being achieved with sudden replacement requirements so more frequent liner measurements need to be taken as the liners near the end of their life.

Multotec Rubber has a sound reputation with its customers where the use of its MultoScan system has been implemented. Using the MultoScan measurements and the SCADA data that the company receives from customers, it is possible to generate an accurate report on the performance of the mill. This enables Multotec’s technical team to engage with the mill operator directly in terms of mill performance and costs.

“In many instances, it is possible to make recommendations based on this data motivating for an earlier mill liner change out as this can dramatically reduce operating costs and increase overall plant efficiency,” Hearn explains.

What is most important in this scenario is Multotec’s ability to use the data generated to accurately determine the actual payback period for the new lining. As an example, Hearn talks about one customer where Multotec found that by replacing the mill lining ahead of the plant’s replacement schedule it was possible to increase the efficiency of the entire plant with a payback period of only days. In this instance, using available data it was easy to distinguish that even though the lining appeared to have an acceptable remaining life, the efficiency of the milling circuit was well below plant design requirements.

“Achieving these increased efficiencies is what is attracting our customers as they can clearly see the advantage in replacing the mill linings at the most cost advantageous stage. And being able to assist our customer using accurate data to make informed decision such as this is a major differentiator for us and them,” Taylor concludes.

The introduction of MultoScan several years ago made it possible for plants to accurately measure mill liner profiles. Using this information end users can easily and accurately predict the lifespan of the liner and the point at which the mill will become inefficient. The automatic measurement and display of the charge level is valuable in confirming that the operation of the mill is correct and this value is essential in calculating the trajectory.

Highly skilled technicians take the data acquired by MultoScan and leverage Multotec’s Hawkeye proprietary programme to interpret and analyse the data. Significantly there is no time lag on the information analysis which makes the level of responsiveness possible unprecedented, and allows customers immediate feedback on the condition of the liners and any immediate issues can be addressed on the spot.

Another very important advantage is the repeatability of the results which is considered an enormous benefit as there is virtually no room for human error. MultoScan also reduces the time spent in the mill taking readings, decreasing mill stoppage time, another significant cost saving for mines.

Having access to accurate information on the liner profile will allow maintenance crews to set the trigger point for the liner inventory. This will, in turn, allow plants to reduce the liner stockholding drastically optimising the inventory; another cost saving.


Being locally registered in Mozambique and well-staffed with 26 highly trained and qualified Mozambican nationals, Multotec Services Mozambique Limitada has secured supply contracts for processing equipment with some of the country’s major role players.

“We were the first mineral processing company to establish a facility in Tete province – back in 2011,” says Thinus Kruger, Multotec’s regional manager for east Africa. “We now have a solid presence with our full range of mineral processing solutions, as well as maintenance and fabrication services.”

Kruger emphasises that the company’s global strategy is to be located close to customers, not just in-country but as near to operational sites as possible.

“Our branch is situated within 20 to 100 kilometres of all our major customers, making for fast response times in terms of maintenance and support services and for the delivery of emergency spares,” he says.

Multotec Services Mozambique’s customer base now includes four major coal players, a graphite mine and a heavy minerals mine, as well as mineral separation plants and harbours. So well equipped is the branch that it is also used as a base for servicing customers in Zimbabwe and Madagascar. Among the full fleet of vehicles to enhance customer service is an eight-tonne crane truck for collection and deliveries, a personnel transporter, double-cab vehicles for service support, two forklifts, an equipped standby trailer, and a rugged HDPE welding trailer for overland installations of HDPE pipes.

Situated just off the main road between Tete and Moatize, the Multotec facility is just 10 km from the airport and 15 km from customs, and boasts a 1,000 square metre fabrication workshop with a bending break, guillotine, pedestal drill, power saw and a variety of welding machines.

“Leveraging the local team’s combined 60 years of experience in mineral processing, our company in Mozambique offers long term maintenance contracts, supply contracts and fixed price agreements to suit customer requirements,” says Kruger. “We also conduct small to medium-scale steel fabrication and specialise in the manufacturing of steel chutes, launders, steel pipes and general fabrication work, including carbon steel, stainless steel, aluminium and welding and installation of HDPE pipes.”

The range of work carried out for customers encompasses service exchanges and refurbishment on cyclones, the retro-fitting of belt cleaners, samplers and cyclone clusters, and preventative or reactive maintenance of screening and other process equipment.

Quality of services is ensured by ongoing investment in local employees through training on-site and advanced training in Multotec’s South Africa-based training centre, which hones employees’ skills in installing and maintaining Multotec products, as well as in the ceramic lining of equipment.

Refurbishment of cyclones forms part of Multotec Services Mozambique’s market offering.

This focus on skills has allowed the company to develop a depth of expertise that – in addition to a commercial manager, accountant and human resources officer – also includes a metallurgical process specialist, an engineering and fabrication specialist, ten artisans or technicians, four HDP pipe welders and nine artisan assistants and installers. The company’s capacity is enhanced by technical support from the Multotec head office in South Africa.

“We regularly fly our Multotec equipment specialists to Mozambique to assist with on-site training for our customers, as well as to conduct audits on their installed Multotec equipment,” says Kruger.

He expects that employment numbers in the company are likely to rise over the coming year as business grows, and a full bursary is being provided for a local university student in the field of teaching education.