Tag Archives: Multotec

Multotec’s SX10 low density spiral opens up coal separation options

Multotec Gravity Division says its new SX10 low density spiral further extends the benefits this innovation offers in fine coal beneficiation, with the technology able to produce both thermal and coking coal on one spiral.

The Multotec SX10 low density spiral’s reduced cut point of 1.55 g/cm3 delivers considerable advantages over the cut points of between 1.6 and 1.8 g/cm3 typically achieved in the coal industry today, according to Multotec Technology Manager, Faan Bornman.

The result, he says, is cleaner coal with less waste being achieved in a single stage. This helps achieve savings on capital costs as no further spiral stages are required for cleaning down the line.

“The approach taken with the Multotec SX10 spiral is to remove the gangue, or mineral containing particles, from the trough in two off-takes,” Multotec said.

The first off-take removes ash, opening up the available separation surface of the spiral and allowing the remaining material to separate more easily. This separates clean coal from less-clean coal.

“The low density spiral is essentially a primary and secondary stage on one centre column,” Bornman said. “Rejects are discarded into the centre column and the remaining product is re-pulped before being sent to a secondary off-take.”

Facilitating the two off-takes is a longer spiral on the Multotec SX10. This increases the residence time and gives the particles sufficient time to separate, according to the company.

Depending on the setting of the product box splitters, this new spiral has the ability to produce both thermal coal and coking coal on one spiral, Multotec claimed. Bornman said this was proven through test work done in the US where the two offtakes enable the removal of most of the gangue leaving a middlings and cleaner coal products to be collected at the dart splitters.

Experimental work was carried out using coal from two South Africa collieries as well as doing site test work in the US. Promising results were obtained leading to the first order for Multotec SX10 spirals from a North America-based mine, it said.

Multotec trommel solution hits the right note at Tronox’s Namakwa Sands

Original equipment manufacturer, Multotec says it has won a tender from Tronox’s Namakwa Sands to replace a trommel at the mine’s Primary Concentration Plant East (PCPE) at its Brand se Baai site, in South Africa.

Greta Mantell, Technical Sales Representative at Multotec Manufacturing, said the scope of supply included the trommel screen, screen panels and ancillary equipment which formed part of the installation at the PCPE.

Mantell said: “What was essential on this particular project was that the new Multotec trommel would replicate the exact process functionality of the old unit and provide the same level of operational performance and reliability as the old screen had for the past 12 years.”

In this application, the Multotec trommel screen is used to classify East mine run-of-mine (ROM) by size and discharge the oversize to the tailings conveyor. The undersize is processed as normal.

“Significantly, this screen is the only piece of equipment operating in the ROM processing circuit for which there is no standby or bypass alternative,” Multotec said.

Tronox’s PCPE uses sea water for its processes and this, together with operating in the harsh west coast environment, meant corrosion protection was a priority on the trommel. It has been supplied with replaceable polyurethane shell protectors as well as a high performance corrosion protection paint on all the non-rubberised surfaces. The trommel screen is fitted with Spalto polyurethane panels selected to ensure optimum throughput and wear life, according to Multotec.

With a focus on improving total cost of ownership, Multotec implemented its one-side fitting of screen panels on the trommel, and Mantell said this will facilitate quicker panel changeouts, saving on costs. As panel maintenance now only needs to be executed from the inside, safety will also be enhanced during this activity, the company said.

The new Multotec trommel is 7.2 m long and has a diameter of 2.5 m. The total mass of the trommel, including panels, is 12.5 t.

The new trommel was delivered on time and installation was done by the mine with Multotec handling the commissioning, the company said. Mantell said that after trouble-free installation, the trommel screen immediately operated at 95% of its design capacity and one day later full feed of 1,000 t/h was maintained.

Mato Products makes its mark on conveyor belt cleaning market

Mato Products, a Multotec company, says it has expanded its bulk handling equipment reach into the design of innovative belt cleaning systems for a number of mineral and metals markets.

The company has long been a household name in clip fasteners for conveyor belts, especially in the underground coal sector. It company operates one of only three high production Mato machines in the world, and significantly the only one outside of Germany.

After over 30 years of operation, this Mato unit was overhauled in 2016 in an intense six-month refurbishment. It was upgraded from 180 t to 360 t capacity, speeding up production and ensuring both ongoing cost-effectiveness and reliability of supply for customers, according to the company.

Mato said: “The company’s exciting line of belt cleaning equipment has for some time now been gathering momentum. Its popularity has extended well beyond the coal sector into other materials handling and mineral processing applications, even in diamond mining.”

According to Benjamin Sibanda, Managing Director of Mato Products, over-feeds at transfer points often lead to material build-up on the inside of a belt.

“As mines and other industrial facilities raise their environmental standards, they want to avoid problems like duff heaps under conveyors, which can cause pollution,” Sibanda said.

The Mato MCP3-S primary cleaner, installed at the head pulley is designed to be an aggressive head pulley cleaner, yet friendly to the conveyor belt surface and suitable for use with mechanical fasteners, the company said.

“It offers a high level of cleaning due to its blade profile, and the spring tensioning system ensures the blade is in constant contact with the belt for the life of the blade while achieving up to a maximum of 75% cleaning.”

Sibanda said: “The secondary Mato MUS2 belt cleaner is one of our latest design belt cleaners and offers an M-TRAK slide on cushion and blade for easy installation and maintenance.”

The M-TRAK is designed to eliminate lengthy maintenance downtime and ensures blade alignment is 100% true across the entire conveyor belt width, according to the company. Blade replacement is simple with the design of the slide-on and slide-off principle, eliminating the need for special tools or training when maintenance is performed, Mato said.

Sibanda continued: “The unique design of our MUS2 cushion is based on the principle of a parallelogram whereby the cushion also stays true to the conveyor belts surface ensuring the angle of attack is maintained. This cleaner’s primary duty is to remove fines and duff, to almost zero carry-back.”

Blades on the cleaners come in a range of materials suited to different applications, including polyurethane and tungsten.

While the application in South Africa was initially mainly underground, equipment variations for surface have now also been developed and introduced to market, Mato said. The plant tail-end cleaner is based on the same concept but is mounted on channels rather than on stringer pipes.

“This product includes innovative blade stoppers,” Sibanda said. “When the blade is worn to a certain level, the mounted flat plate does not touch the belt, for better protection.”

Mato has also engineered closer integration between its fastener clips and the belt cleaners.

“For instance, we have added a profile to the clip which optimises the life of both the clip and the tungsten tip on our secondary belt cleaner,” Sibanda said. “The skiving process embeds the clip slightly into the belt ensuring the mechanical splice is on the same surface as the conveyor belt thereby minimising the impact on the tungsten tip as well as lowering noise levels. Longer life of both means less downtime for the customer and greater reliability.”

Sibanda said all the offerings in Mato’s conveyor belt systems range helps to improve the lifespan of equipment at loading points. The energy of ore transfer is absorbed, and wear resistance is increased by Multolag ceramic products.