Combined Recovery Technology of Stirred Leaching/Heap Leaching-Extraction-Electrodeposition for a Low-grade Oxidized Copper Mine in Congo (DRC)

A mining area in Congo (DRC) contains a large number of low-grade copper oxide ore resources, with a copper grade of 1.74%. The ore has a low recovery rate by flotation, high ore powder content, and poor ore permeability, so it is impossible to directly use the heap leaching process to recover copper metal. The results show that when the ore crushing particle size is 60 mm, the ore is washed and classified, 32% of the -1 mm ore enters the stirring leaching, the copper leaching rate is 91.96%, and the consumption of copper acid per ton is 5.23 tons, and 68% of the +1 mm ore enters the heap leaching, the copper leaching rate is 80.33%, and the copper acid consumption per ton is 4.33 tons. The comprehensive recovery rate of the combined process is 81.79%, and the comprehensive cost is \4 088 per ton of copper. When the unit price per ton of copper is \5 000 and \10 000, the net profit per ton of copper is \178 and \3 401, respectively.