Tag Archives: pumps and pipelines

FLSmidth reflects on KREBS slurry pump dominance in Africa

KREBS® slurry pumps have become leaders in mill discharge applications in Africa, with the latest Ultimate Mill Discharge (UMD) pump leading the way in these heavy-duty applications, according to FLSmidth.

Andre Hall, FLSmidth Regional Product Line Manager — Pumps, Cyclones and Valves, said: “West African gold mines and the copper operations of Zambia and Democratic Republic of Congo are among the areas where these robust pumps dominate.

“Their popularity,” he says, “is based on their long wear life and high efficiency.”

Ghana is a particular success story for UMD pumps, according to Hall, with nearly all gold mines there using the equipment manufacturer’s pumps to discharge slurry from their mills, he added.

“The KREBS UMD is popular at these mines largely because it lowers the total cost of ownership due to the millMax™ proprietary design that eliminates inefficient recirculation and grinding of slurry within the pump,” FLSmidth said.

“Prior to the millMAX wear ring design, slurry pumps experienced two major problems: mechanical grinding of solids between the suction liner and impeller, and flow recirculating back to the impeller eye on the suction side. Both of these problems decrease pump life and increase power consumption.”

The wear ring stops recirculation by closing the suction-side gap, while still allowing for a large clearance between the impeller and the suction liner, according to FLSmidth. This eliminates the grinding of solids. Adjusting the wear ring while the pump is running, meanwhile, restores performance and provides longer wear life and higher continuous efficiency, in all, lowering the total cost of ownership.

Hall says: “The UMD’s casing symmetry also means less inventory for customers. Mines that have pumps rotating in both left-hand and right-hand orientations must stock different casings, liners and impellers, adding to the operational costs.”

The advantage of the UMD is that it uses the same casing, suction liner, wear ring and back liner, which reduces overall net working capital.

The KREBS gravelMAX™ pumps continue to do well in the Mpumalanga coal sector of South Africa, according to FLSmith, where 14 of these pumps recently replaced competitor units on a single site.

Commonly applied in a cyclone feed application within the dense medium separation (DMS) circuit, the pump’s wider passage allows pumping of larger solids.

“We are also active in iron ore in South Africa with pumps in the DMS circuit,” Hall says. “A Lesotho diamond mine also operates KREBS pumps, which have demonstrated a four-fold increase in wear life compared to a competitor’s previous units.”

In sump pumps, FLSmidth has the vMAX™ range, which features a recessed impeller design allowing the pumps to run dry.

The company explains:“When the sump has been emptied of slurry, the recessed impeller allows the slurry to return safely down the discharge pipe without contacting the impeller, ensuring that it does not vibrate when dry.”

Another recent innovation in the KREBS slurryMAX range of pumps is being introduced to the Africa market after an enthusiastic response in the US and Australia, FLSmidth said. With multiple liner and impeller material options, the slurryMAX split-case pump can handle the majority of applications for any plant across multiple industries.

Pleuger pumped up with Collahuasi copper mine contract win

Germany’s Pleuger Industries has installed six robust high-performance pumps at the Anglo American- and Glencore-owned Collahuasi copper mine in Chile, helping the operation continue to produce more than 5,000 tonnes of fine copper every year.

At Collahuasi, two open-pit mines, Rosario and Ujina, provide the necessary copper ores, which are smelted on site into copper concentrate and cathodes. Pleuger’s 10 in pumps come in during the flotation process at Collahuasi, where they help dewater the copper sludge for copper concentrate extraction.

The acceptance of the six pumps, for which the technical management of the mine together with the pump distributor Wellford had travelled from Chile to Hamburg, took a week. “This is not unusual when one considers the significance of the new submersible motor pumps for the processing of copper sulphide,” Pleuger said. “If the pumps fail, the production process comes to a standstill until the pumps are repaired. Reliability, therefore, has top priority.

“The decision in favour of a pump manufacturer is, therefore, less a question of one-time costs than of confidence in the technical know-how of the engineers.”

Wellford, from Chile, Collahuasi’s pump supplier, brought Pleuger into play because the German pump manufacturer has decades of experience in designing pump units for the special requirements of the mining sector, the Germany-based company said. “Pleuger’s engineers have acquired their expertise in various customising projects around the globe, which the Hamburg-based company continuously uses in the construction of its engines.”

Process pumps like the ones used at Collahuasi are placed under extreme operating conditions, Pleuger said.

“Copper… quickly oxidises the materials from which pumps are usually made. In order to counteract this process, the engineers at Pleuger Industries rely on a corrosion protection concept specially adapted to the customer when designing the pumps,” the company said.

“In addition, the new pump systems must be energy-efficient, because Collahuasi’s copper production follows an energy management system based on international standards.”

Metso pumps business area going with the mining flow

Metso used the recent Bauma fair, in Munich, Germany, to showcase several new solutions, including its MDR500 pump for mill discharge applications.

The MDR500 fits on a frame 1400 and is the largest frame for the MD series to benefit from an innovative pump maintenance slide base, Metso’s Director EMEA, Pumps business area, Steve Sedgwick told IM at the event, ahead of the publication of its annual feature on pumps and pipelines.

In terms of routine inspection or repair, this design allows the complete bearing frame and rotating element to be removed as a unit; thus, impeller, complete gland seal component and back liner renewal can be carried out rapidly and safely. The inlet and discharge piping can remain in place, which aids health and safety.

The MD series has been designed speci¬fically for mill discharge, very abrasive applications and cyclone feed duties, offering sustained efficiency and performance, on top of operational reliability and durability, according to Metso.

The company says it uses only high-performance materials for its MD pumps that come with excellent resistance to abrasion and erosion. Special emphasis has also been placed on components able to withstand exceptional wear from coarse heavy solids due to the modern hydraulic design.

“An oversized robust steel shaft and extra thick casings and liners are just some of the heavy-duty components equipped on our MD series pumps,” Metso said.

While the MDR500 on the Metso stand came with a rubber lining, the company also provides an alternative metal lining for coarse feeds (MDM500).

The pump (MDR500), which as the name implies comes with a 500 mm inlet, has a large diameter, slow-running impeller, on top of double adjustment feature ensuring both suction side and gland side impeller clearances can be set perfectly from new, and maintained throughout the wear life of the components.

This specimen on show was, by far, not the largest model available, with Metso saying it can meet most flow and head requirements for the intended applications.

Last year, the company introduced a new pump test rig at its Sala facility, in Sweden, equipped with a 2 MW motor that could accommodate the company’s largest mill discharge pump – the MDM650 and larger. Some of the pumps tested on this new rig have already been dispatched to a mining customer in South America.

Sedgwick said the company had also sold many pumps to miners in several countries in recent years – for base metal and other operations – and was continuing to register good demand from mining companies around the world focused on gold, iron ore and copper.

He said Metso had also recently made a delivery to a company in the CIS where the pump was being used in conjunction with high pressure grinding rollers in a hard-rock comminution circuit.

Metso doesn’t just supply the pumps that go into these heavy-duty applications, though. It has also helped integrate the equipment into the operations they were built for by supplying rubber pipes, valves and other solutions to ensure they operate to their full ability.

A case in point is Boliden’s Aitik mine, just south of Gällivare in the north-central part of Sweden, where an expansion project to take the operation from 36 Mt/y of throughput to 45 Mt/y has been going on for the past few years.

This 25% increase in production – that came with a subsequent rise in the output of copper concentrate – required every part of the Aitik plant to be optimised, Metso said.

Initial investigation showed if concentrate volumes were to step up with this expansion, the mine would run into capacity limitations with the existing tailings from the plant.

The miner needed a proven solution fast in order to achieve its production goals. It also required one that could cope with environments where temperatures could vary from -40°C to 30°C.

This is where Metso suggested a solution consisting of heavy-duty slurry pumps and rubber-lined steel pipes designed for rugged applications.

The company supplied 16 km of natural rubber-lined pipes, ranging in size from DN200 to DN600, with rubber compensators and branch pipes, and the heavy-duty pumps. The pipes offer five times longer wear life compared with a typical polyethylene pipe, according to the company, and were supplied alongside rubber hoses, and rubber bends equipped with thick long-wear rubber and an “ultra-smooth surface” for low flow resistance to increase the tailing capacity.