Abstract: A lead-zinc sulfide ore from Sichuan is a low-grade,high-calcium refractory ore,with lead and zinc grades of 1.41% and 8.12%,Respectively;Lead and zinc mainly occur as sulfides.Due to the low lead grade and high content of calci um-bearing gangue minerals,conventional flotation cannot achieve effective separation and recovery of lead and zinc.To achieve efficient development and utilization of this ore,flotation separation tests were carried out.A preferential flotation process was a dopted,with self-developed YTH as the collector and zinc sulfate and sodium sulfite as combined depressants.The process flowsheet and reagent regime were determined through flotation condition tests.The results showed that a full-process closed circuit test using the flowsheet of "preferential lead flotation and zinc flotation from lead flotation tailings",in which both lead and zinc flotation adopted one roughing,one scavenging,and three cleaning stages,yielded a lead concentrate with a lead grade of 63.57%,a lead recovery of 75.52%,and a calcium content of 0.19%,as well as a zinc concentrate with a zinc grade of 57.37%,a zinc recovery of 73.62%,and a calcium content of 0.74%.This process achieved the effective development and u tilization of low-grade,high-calcium lead-zinc sulfide ore and can provide guidance for the industrial production of similar ores.

Key words: sulfide lead-zinc ore,high-calcium ore,flotation separation,preferential flotation,calcium-bearing gangue, YTH