Beneficiation Test of a Low-grade Lead-Zinc Ore Containing Silver

The lead and zinc contents of a lead-zinc sulfide ore are 2.25% and 1.96% respectively. The associated silver content is 13.20 g/t. The main lead-zinc minerals are galena and sphalerite. Their symbiotic relationship is close and their distribution is complex. In order to recover and utilize the resource efficiently and comprehensively, the beneficiation test was carried out. The results show that the process of preferential flotation of lead and zinc accounted for 65.00% of the grinding fineness of raw ore at -74 micron, with lime as pulp pH regulator, zinc sulfate as inhibitor, ethyl sulfide nitrogen as collector, lead was concentrated twice after one roughing, two sweeping-lead concentrate regrinding to -37 micron accounting for 82.70% and lime as tailings. The lead concentrates with 66.43% lead grade, 309.71 g/t silver grade, 95.97% lead recovery, 74.87% silver recovery, 53.35% zinc grade and 90.35% zinc recovery were obtained by primary, secondary and secondary cleaning of zinc with pH regulator, copper sulfate as activator and butyl xanthate as collector.

The main valuable elements recoverable from a lead-zinc ore in Yunnan Province are lead and zinc with contents of 2.25% and 1.96% respectively, and associated silver with content of 13.20g/t; lead in the form of sulphide accounts for 94.71% of total lead, zinc in the form of sulphide accounts for 93.25% of total zinc; lead mainly occurs in galena and lead in galena. The content of zinc is 2.604%. Zinc mainly occurs in sphalerite, and the mineral content is 2.924%. 2) The preferential flotation process is adopted, in which the grinding fineness of raw ore is -74 micron accounting for 65.00%. Lime is used as pulp pH regulator, zinc sulfate is used as inhibitor and ethyl sulfur nitrogen is used as collector. After one roughing, two sweeping and second grinding to -37 micron accounting for 82.70%, lead is concentrated twice. Lime is used as pulp regulator and copper sulfate is used as tailings. For activator and butyl xanthate as collector, lead concentrate with 66.43% lead grade, 95.97% lead recovery, 53.35% zinc grade and 90.35% zinc recovery were obtained by one roughing, two sweeping and two concentrating of zinc. Silver was mainly concentrated in lead concentrate with a grade of 309.71 g/t and a recovery of 74.87%.