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.