Tag Archives: Multotec

SUCCESS FOR NEW CERADOX HIGH IMPACT SCREEN PANEL

Combining decades of experience with its leading R&D and manufacturing capability, Multotec has developed a high-impact screen panel that cuts plant downtime and boosts mine productivity.

The Ceradox panel – incorporating both Hardox blocks and alumina ceramic tiles – boasts more than double the wear life of traditional rubber panels. The innovation was developed during 2019 in response to a request from an iron ore mining customer in Australia’s Pilbara region. Three months of testing delivered results that exceeded expectations, said Multotec screening product manager Shawn Faba.

“The customer needed a panel with an extended wear life, so that they only needed to conduct replacements during the regular maintenance shut-down every 12 weeks,” says Faba. “Our testing demonstrated that the panels were lasting 24 weeks and longer.”

Through a close collaboration between Multotec South Africa, Multotec Australia and the customer, an innovative solution was developed and proved for a demanding application on scalper screens.

“Designed for the impact area of the scalper screen, the Ceradox panel must withstand the impact of material up to 300 mm in size, falling from a discharge height of up to three metres,” he says. “It must also resist high levels of abrasion from the ore.”

The resulting design leverages the impact strength of the Hardox blocks and the abrasion resistance of the ceramic tiles, embedded in Multotec’s proprietary rubber formulation which helps absorb the energy of the falling material. The panels are manufactured locally at Multotec’s high-volume facilities in Gauteng, which include a rubber mixing plant run by experienced rubber specialists.

Faba notes that the 305 mm square Ceradox panels can be manufactured to different thicknesses from 50 mm to 100 mm.

“With our local manufacturing capability, we can achieve short lead-times and deliver to anywhere in the world,” he says. Multotec already supplies about 35% of the screening media to the iron ore mines in the Pilbara area.

ON-SITE TESTWORK AT REFINERY PAVES WAY TO QUALITY BOOST

On-site testwork at a South African base metal refinery allowed Multotec to prove its sievebend solution for improving the quality of the customer’s product to market.

According to PJ Pieters, process engineer at Multotec, the refinery was looking for the most efficient way to reduce impurities to less than 200 parts per million in the product stream.

“As the contaminants were found mainly in a specific size fraction, the aim was to remove this fraction by classification using a sievebend,” says Pieters. “To test this proposal, we used our mobile sievebend test unit which we could take onto the customer’s site and link up to one of the product streams in the plant.”

This provided a convenient way to conduct testing under normal plant operating conditions. It also meant there was no need to remove any valuable mineral product from the site, which could demand onerous security compliance procedures. The tests took only a week to conduct, after the mobile units were installed.

“The tests were conducted to reduce impurities and to measure the effect of the sievebend on the downstream screen scroll centrifuge,” he says. “We managed to achieve the product quality goal, while also maintaining optimal centrifuge performance in terms of the customer’s product moisture requirement.”

The addition of a sievebend to the process will not increase the energy costs as the machine is operated under normal gravity conditions and is compact enough to fit inline between existing process equipment.

To withstand the highly corrosive application, the sievebend and its housing were manufactured in stainless steel. By using appropriate sampling techniques, the testwork was able to deliver very representative results. This gave the customer an accurate expectation of the precise results that a full-scale installation would deliver.

“This kind of testwork adds confidence to the customer’s decision to invest in a specific solution,” Pieters says. “It is also part of Multotec’s contribution to continually improve customers’ process efficiency; we work to provide the customer with the best knowledge and products to optimise their plants.”

Another element of the valued added by the sievebend, says Pieters, is that the refinery is likely to save on potential penalties arising from impurity levels in the saleable product. Multotec also provides after-sales optimisation and support to ensure on-going benefit from the innovations applied.

MULTOTEC PLEDGES CUSTOMER SUPPORT DURING COVID-19 PANDEMIC

While respecting Covid-19 lockdown and other regulations, Multotec has assured customers globally of its technical and sales support, especially to operations declared as essential services.

As a global company serving six continents, Multotec has operations in Canada, Chile, Australia, Europe, China, Ghana, Zambia, Botswana, Mozambique and South Africa.

“We certainly find ourselves in challenging times and the global Covid-19 pandemic is giving us the opportunity of modifying the way we do business across the world,” says Multotec CEO Thomas Holtz.

With South Africa currently in lockdown, Multotec is producing only ‘essential services’ products there, but expects to return to full production at the end of the lockdown on 17 April 2020, says Holtz.

“Our manufacturing facilities in China are fully operational, while our facilities in Canada, Chile and Australia are in various stages of operational capacity,” he says. “We have committed to working on weekends and over public holidays over the next months to ensure any order backlogs are caught up and there is the least possible disruption.”

Holtz highlights that where some countries’ mining and power generation operations have been declared by their governments as essential services, Multotec is providing full product and service support from its local bases in these locations.

“The safety of our staff and customers is an absolute priority and every precaution is being taken to ensure the continued health of all our stakeholders,” he says. “At the same time, please be assured that – as far as possible and using various means – we continue to provide full technical and sales support to all our customers, wherever they may be.”

Multotec has taken the worldwide travel restrictions as an opportunity to run online training workshops in multiple languages with many customers in remote locations. There are also informative training videos available on the company’s YouTube channel.

MULTOTEC CENTRIFUGE EXCELS IN FOOD SECTOR

Well known in the mining sector for dewatering and other mineral processing solutions, Multotec Process Equipment has also been growing its footprint in food and chemical applications.

A recent installation by the South Africa-based original equipment manufacturer (OEM) successfully assisted a salt producer in Namibia in reducing moisture content in its product. According to Multotec Process Equipment senior process engineer Khathutshelo Mutshinyalo, a fit-for-purpose vibrating centrifuge was the answer in this application.

“The customer had a specific requirement to achieve a low moisture level in their coarse salt application,” Mutshinyalo says. “However, we also needed to prove upfront that our solution would deliver the correct result.”

With its experience and its in-house testing facilities, Multotec was able to define a test work method to meet the customer’s precise needs. It was also able to draw on the capabilities of its state-of-the-art Centrilab technology – developed by sister-company Siebtechnik Tema. The Centrilab tests the separability of suspensions in the centrifugal field, by simulating the particular centrifuge operating conditions.

“This allowed us to specify the optimal machine for the customer, and prove the results before the order was placed,” he says. “The vibrating centrifuge we specified features a maximised area inside the housing, to optimise the dewatering process.”

The result was that Multotec’s centrifuge achieved a moisture content 10% better than the customer’s expectation. Achieving better than the desired moisture content ensures that there is minimal to no formation of lumps in the product, which saves the customer potential penalties.

“By testing to ensure the right solution, and deploying a product specialist and technician on site, we could commission the centrifuge outside South Africa within a week,” he says. He notes that Multotec’s footprint with this technology includes companies in South Africa, Botswana, and Kenya using it for similar applications.

CUSTOM CYCLONE SOLUTION SOLVES ZAMBIAN TSF CHALLENGE

An innovative hydrocyclone solution from Multotec is allowing a large Zambian copper mine to develop a safe and cost effective tailings storage facility (TSF).

The TSF faced a number of specific challenges, according to Frikkie Enslin, senior applications engineer responsible for cyclones at Multotec,  including its extensive planned capacity and the area’s flat topography. The mine’s process plant pumps some 10,000 m3 per hour of tailings to the TSF, requiring its final circumference to reach about 19 km.

“The flat area around the mine meant there was no suitable topography to provide a natural dam,” Enslin says. “It was therefore vital to create strong walls to retain the slurry from the plant, so that the integrity of the TSF could be assured.”

Simple gravity separation and sun-drying had proved unable to create material firm enough to constitute walls. In the early days of the plant’s operation, it was shown that material being deposited by means of plain spigoting could still not be walked on even after a month of drying in the sun. By contrast, Multotec’s 250 mm GV hydrocyclones were able to deliver an underflow discharge that could be walked on in just two days. After a week, the material could withstand the weight of an excavator.

The sheer volume of slurry being pumped into the TSF, however, created its own challenge. The hydrocyclones had initially been mounted on metal cradles, which were inundated within a couple of hours. Extracting the cyclone and cradle from the mud for the next placement was difficult and very time consuming.

“The customer needed a solution that would keep the cyclone above the slurry level for longer, and would be easier to move,” he says. “To do this, we designed a cyclone cradle that could be attached to a long wooden pole, giving much greater height, allowing the customer to leave the cyclones in the same position for a much longer time.”

With Multotec’s experience and facilities for custom design and manufacture, the hydrocyclones were then modified to be lighter. This made them easier to handle and manoeuvre.

“Constructed with a lighter metal, these tailormade units are industry leaders in terms of lightweight and are rubber-lined to ensure long wear life,” he says. “We also made some innovative improvements to the vortex finders and the cone sections, which are now metal spun.”

Other changes were made to speed up the changing of a spigot, and the moving of the hydrocyclones from one point on the TSF wall to the next. The design now includes a threaded spigot coupling and quick-release connections on the cyclone.

The solution has been so successful to date that over 250 of Multotec’s modified GV hydrocyclones have already been installed.

“Just as we collaborated closely with the customer in developing this solution, so we continue our partnership in monitoring the performance of our hydrocyclones as the project goes on,” Enslin says. “An expert applications engineer from our Johannesburg head office visits the site regularly, while our Zambia office in Chingola offers solid technical and field service support. We don’t just sell process equipment, but rather process solutions.”

FILTER PRESS SAVES WATER, REDUCES IMPACT

A Limpopo chrome mine faced various risks in disposing of its tailings and called Multotec for a solution.

The chrome operation was aware of the challenges that a traditional tailings storage facility (TSF) could create, according to Multotec Process Equipment senior process engineer Khathutshelo Mutshinyalo. These include the large footprint of a tailings dam, the expense of lining the tailings dam and the environmental and social impacts.

“The mine management was keen to conserve scarce water resources by avoiding evaporation,” Mutshinyalo says. “They also wanted to prevent any potential groundwater contamination that might result from solution seepage. There was also the local community to consider, to which a normal TSF could present a risk.”

Multotec was able to explore the full range of its dewatering solutions before recommending the most suitable one for this application, he says.

The filter press technology was the chosen option, as it was shown to meet the duty requirements in the most cost effective manner. As a well-proven mechanical dewatering strategy, the filter press was able to immediately recover about 80% of the clean water in the slurry.

“The cake that is left from the tailings after water removal is then easily moved by conveyor to a dump area,” Mutshinyalo explains. “This dump is much simpler and safer to manage than a tailings dam.”

The solution facilitates short cycle times, less wear on consumables and lower power consumption. The cakes are also easily released from the cloth and leave little residue behind on the cloth. He highlights that the process of reaching the selected solution was driven by thorough investigation, extensive test work, and many years of experience in the field. It always begins with a detailed understanding of the conditions that exist at the site, as well as the customer’s priorities.

“With the support of the research team at our testing facilities in Spartan, we were able to test the behaviour of the customer’s slurry samples with various Multotec solutions,” Mutshinyalo says. “This allowed us to confirm not only the best technology for the application, but also to innovate our equipment for optimal results.”

In this case, the abrasive impact of the tailings material was one of the key factors to be accommodated. While the filter press was proven to be the most effective solution, there was still considerable wear experienced by the filter cloth in the press.

“Combining our field experience and metallurgical expertise, we looked more closely at possible innovations for this aspect of the equipment,” he says. “We developed an improvement that would better protect the high-wearing areas of the filter cloth and deliver longer wear life.”

The detailed preparation behind this solution, and Multotec’s practical expertise in installing and maintaining its equipment, meant that final commissioning on site could be done without delay.

Mutshinyalo notes another recent application of filter press technology was in coal tailings, this time for a coal mine in the Mpumalanga area. Test work was again effectively used to find the solution best suited to the application.

“Here, we needed the filter press to operate in demanding conditions including a high tonnage throughput,” he says. “Once again, the focus was on innovation where we customised the filter cloth to improve its rigidity and life.”

The result was that the cycle life per cloth was doubled based on typical tailings applications – a considerable improvement in the wear life. Apart from the robustness of the filter press, the feed arrangement and process control were optimised to suit the process.

In addition to these applications, Multotec has also applied filter press solutions to copper sulphide, copper oxide and gold sludge applications. The company’s range of equipment and depth of technical expertise allows turnkey solutions which include the various items of auxiliary equipment around the filter press.

“Our branch infrastructure and network around the country gives us a quick response capability with our customers,” he says. “We are always mindful that – alongside the optimal solution – customers need quick action by all partners to keep operations running smoothly.”

MATO EXPANDS FACILITIES AS IT GROWS MARKET

The growing popularity of the MATO Products’ expanded offering has led the company to boost its service and repair facilities.

Andrew Frank, operations manager at MATO Products, highlights the recent completion of the new spray-painting booth, which has doubled the firm’s capacity to finish refurbished items. Well known as a leader in conveyor belt lacing, the Multotec subsidiary also offers a range of belt cleaning solutions.

“To keep up with market demand, we have expanded our spray booth significantly in terms of size and throughput capability,” Frank says. “It can now accommodate components up to a length of 2,2 metres and provide a more productive environment for operators.”

This now allows for all repair and finishing work – even on the longer diagonal belt cleaners – to be spray-painted in-house, he says. Importantly, this improves turnaround time, quality control and cost to customer.

“We pride ourselves on the functionality and longevity of our products,” he says. “We base this on our technical quality in repairing and refurbishing equipment to ‘as-new’ specifications. Upgrading our facilities ensures that we continue doing this as cost effectively as possible, as our customer base grows.”

Complying with the highest standards of health and safety, the new spray booth is equipped with the latest filtration technology. This ensures that fumes and chemicals are filtered before air is expelled from the building. A powerful fan unit enables an extraction capacity of 18,000 cubic metres per hour.

“Health and safety are key imperatives in the Multotec Group, and we have ensured that the new system consistently improves our working environment. Spray painting is associated with several health and safety factors which must be considered, and our new spray booth is fully compliant to these regulations and has been certified for use at Mato Products by our local fire department,” Frank says.

“The better ergonomics of the new facility – with more space, light and updated equipment – has been well received by employees.”

He notes that the quality of work on MATO Products’ equipment ensures reliability and value-for-money, while saving customers on costly downtime in their operations.

MULTOTEC EXPERTISE CUTS WEAR AT PHOSPHATE PLANT

In one of its largest scrubber installations to date, a phosphate mine in Morocco is benefitting from Multotec Rubber’s depth of expertise and experience in the field of scrubber liners.

The scrubbers measure 6,5 metres in diameter and 11 metres in length – large dimensions necessitated by the process plant throughput of 12 million tonnes per annum. The installation, conducted during the first quarter of 2019, was done in response to a serious challenge faced by the customer. The existing head plates were wearing out at double the rate of the shell plates. This was leading to additional maintenance shutdowns during the life of the liners, with the associated extra costs.

According to Mohamed Trabelsi, senior sales engineer at Multotec Rubber, the collaboration with the customer included sending a highly competent Multotec team to site to first assess the situation. Multotec already had a longstanding relationship with the customer at this process plant, with Multotec trommel screens having operated successfully at plant for over three years.

“Our team of engineers were on site to gather vital operating information including throughput tonnages, particle size, charge levels and rotational speed,” says Trabelsi. “We also assessed the variable speed drive system.”

This data was processed using the latest simulation software – Rocky DEM – in which Multotec Rubber has made a significant investment. Leveraged by well qualified engineers, this software can simulate the full lifecycle of liners and predict when the scrubber will no longer perform efficiently.

“By combining our experience and expertise with the results of Rocky DEM, we are able to provide the industry with fit-for-application solutions,” he says.

Rocky DEM allows engineers to accurately simulate all operating parameters in the scrubber. These include the shape and size of ore particles in the slurry being fed into the scrubber slurry, the charge level, the linings, attrition rates, particle trajectories and the scrubber’s rotational speed.

“We can therefore simulate the actual operating conditions of the scrubber, as well as the performance of the head and shell liners,” he says. “Upon our assessment of the results, it was found we needed a different configuration of liners to the previous one in this application. In fact, the solution was a uniquely designed liner configuration – quite different to what is traditionally used.”

He notes that, in Multotec’s experience of high throughput scrubber applications, it is critical to lift the material away from the head plate, thereby alleviating the sliding abrasion which causes excessive wear.

“Our objective was to ensure optimum wear life with the lowest total operating costs,” says Trabelsi. “Efficiency was enhanced by ensuring that the liner profile configuration was suited to the specific operating conditions. By doing this, the wear life in this application has been improved.”

Since installation, the liners have been performing in line with the customer’s expectations and are expected to have a lifespan of over five years. These lifecycle predictions also allowed the payback period to be accurately determined, assisting the customer in making the best operational and financial decision.

The liners are locally manufactured at Multotec Rubber’s world class ISO 9001:2015 facility near Johannesburg, which has benefitted from continued investment in technology over the years.

“Our quality manufacturing facility expedites the production of liners engineered for individual applications,” he says. “The entire process from design stage to installation took just 12 weeks – in response to the urgency resulting from the premature failure of the previous scrubber lining installation.”

Trabelsi also notes that – even after finding an appropriate solution – mines must constantly anticipate changing conditions in their process plants.

“As mines develop, the ore body changes; this brings changes to their throughput capacities and mill operating parameters,” he says. “If a process plant has liners that have run for ten years, it is not necessarily a given that this liner configuration is still suitable for the application.”

He emphasises that it is critical to conduct an assessment exercise in every application, before quoting on a replacement liner. Most importantly, the liners should be engineered in accordance with the current operational parameters on the mine.

“This is why Multotec Rubber considers it so important that our engineers go to site and assess the actual mill operating data for themselves,” he says. “This makes it possible for us to gain access to the information from the plant operating system, so that the best solution can be engineered for the mine.”

He highlights that correctly designed liners will offer greater energy efficiency and reduce media consumption. This is significant, as energy input and media consumption account for around 80% of the grinding costs in the plant – depending on the application.

“The more we are able to simulate, the more accurate information becomes available,” says Trabelsi. “We are then able to accurately predict the savings and payback period that could be expected at the plant – as a result of improved efficiency and reduced power consumption per ton.”

SAG MILL TROMMEL SCREEN PROVIDES SIMPLE MECHANISM TO CLASSIFY LARGE VOLUMES OF MILL PRODUCT

The global mining industry has become more discerning about equipment selection for process plant applications, driven by the need to increase throughput and reduce downtime. The SAG mill trommel is one example that delivers on both fronts. With large volume capabilities and a robust and simple structure, it is considered a viable alternative to vibrating screens in SAG mill scalping applications.

Many designers and mill operators believe that the benefits of simplicity and the ability to handle throughputs in excess of 3 500 tons per hour of solids make trommels the preferred equipment for this application.

“A key component ensuring optimal performance of SAG mill trommels is the screen panel, which enables this equipment to classify large volumes of mill product,” says Francois Fouche, senior screening specialist at Multotec.

The company has developed a special range of rubber compounds that are used to manufacture the compression moulded rubber screen panels which are considered the highest wearing items in the trommel.

“We have achieved excellent results from our compression moulded screen panels with wear life extending over six months in 4 500 tons per hour SAG mill applications,” Fouche states.

Multotec has nearly four decades of experience supplying locally manufactured trommel screens and today has the process capability to size SAG mill trommel screens with diameters up to 5.5 metres. The company also designs its trommel screens to suit each customer’s unique requirements and confidently offers process and mechanical guarantees.

“Considering the size and complexity of large SAG mill trommel frames, Multotec is able to apply the latest Finite Element Analysis techniques during the design phase to ensure we reduce fatigue stresses and ensure structural integrity,” Fouche points out.

Given the arduous duty, Multotec covers all frame surfaces that are exposed to the milled product with a wear resistant material, typically rubber.

Fouche says that the operational performance of a SAG mill trommel is another key consideration for Multotec. “As adequate retention time is required for the efficient removal of the fine fraction we need to reduce the high velocity of the slurry that exits SAG mills. We are able to achieve this with various configurations of weir bars. The design of a set of scrolls is an integral part of the design process as these regulate the flow of solids through the trommel screen,” he says.

Multotec has supplied a number of trommel screens for 38 to 40-foot SAG mills that required 500 to 600 mm high weir bars to create sufficient retention time.

Multotec can also supply a range of rubber shell plates and lifter bars to protect the SAG mill trunnion against wear.

“Providing long term customer support is one of the major advantages that Multotec offers,” Fouche says. “Our experienced competent field service crews maintain the screening media and provide condition monitoring on the trommels.”

The Multotec field service maintenance crews can also focus on wear rate indication and monitor the wear resistant lining of the steel structure, and in doing so provide a complete maintenance solution.

NEW AGENT IN TURKEY TO BOOST MULTOTEC PRESENCE

Mineral processing specialist Multotec has appointed Istanbul-based Turbo Ltd as its new agent in Turkey, according to Bart Malan, Multotec’s international business development manager for Eurasia.

Malan says that while Multotec is not a newcomer to Turkey, having supplied a range of equipment over the past 19 year, there is a renewed focus on this region with the intention to expand its product footprint significantly.

“Over the years, Multotec equipment has been installed in the chrome, gold and coal sectors, and through the appointment of Turbo Ltd we will be able to extend our reach and include a larger range of proven Multotec solutions to the mining and minerals processing industry in Turkey.”

He says Turbo Ltd, an established company of 30 years’ standing, has a strong technical foundation underpinned by the requisite facilities to support its wide customer base. “Having skilled and qualified engineers as well as a strong support team and well-resourced technical capability was a critical consideration when appointing an agent in this important region as this we believe this is what is required to provide the level of support to Multotec customers,” he says.

“We also plan to collaborate with Turbo Ltd in setting up a fully operational laboratory in Turkey,” he continues. “This will give us the advantage of offering mineral test work and sampling for customers.”

Malan highlights that this facility will assist Turbo Ltd in their plant flow designs, supporting customers in maximising the efficiency of their mineral processing operations. While Multotec has historically marketed mainly cyclones and spiral concentrators in Turkey, the future will see a growing range of equipment include samplers, screening systems, flotation components, pumps and magnetic separators.

Turbo Ltd is active in the mining, metallurgy, construction, petroleum and natural gas sectors. With its head office in Istanbul and a branch office in Ankara, it also has a subsidiary in the UK and a logistic supply bureau in the US. The company has a strong focus on high quality aftersales service, and its Istanbul workshop is certified by the Turkish Standards Institute.

“We believe the Turkish market holds considerable potential for Multotec and we will work closely with our new agent to grow our market share,” Malan concludes.