Erosive degradation of pump impeller when handling slurry of copper tailing

THE PROBLEM
Transportation of slurries in the mining industry requires reliable systems of pipes and tubes to handle three types of slurries. The shape and size of slurry particles is determined by the processes of crushing and milling tuned to the requirements of productivity. The chemical composition of the liquid phase is determined by the conditions of the extraction processes, which ranges from acidic to alkaline. The concentration of the solid phase is often as high as possible in order to economize water. An example of a slurry intensive operation is that of re-processing of a tailing material. Figure 1 shows a tailing deposit from the 1970s, which was found to be sufficiently rich in metal to be processed anew. In order to do so, the tailing is liquefied to form a slurry, which is then sent to a distant processing plant by a system of pumps and pipes. However, the relatively high content of metal ions in the slurry challenges the erosion-corrosion resistance of the metallic elements of the pump.