Study on Comprehensive Recovery and Utilization of a Low-grade Gold-Copper Ore in Fujian

A low-grade gold-copper mixed ore in Fujian contains Au 0.36 g/t, Cu 0.29%, Ag 7.4 g/t, S 4.02%. If it is directly cyanidized, copper enters the gold cyanide leaching system, not only cannot be recovered, It will also worsen the gold selection index and increase production costs.For this low-grade gold-copper mixed ore, a combined flotation and cyanidation process is used for sorting. The flotation operation investigated the influence of the fineness of ore grinding, the amount of lime, the type of collector, and the type of dispersant on the flotation index.The results show that the flotation effect is the best when the grinding fineness is -0.074 mm 60%, the amount of lime is 1500 g/t, when Z-200 is used as a collector, and when water glass is used as a dispersant. The ore contains Au 16.74 g/t, Cu 20.21%, and the gold and copper recovery rates are 61.90% and 87.09%, respectively.The flotation tailings were leached by cyanidation, and the influence of sodium cyanide concentration and cyanidation time on the gold leaching rate was investigated. The results showed that the gold leaching rate was 71.26% after leaching at the initial concentration of sodium cyanide 300 mg/L for 24 hours. The recovery rate of Au in the whole process reached 89.05%, and the recovery rate of Cu reached 87.09%, finally achieving the goal of comprehensive and efficient recovery of gold and copper in the ore, providing technical support for the development of such resources.