Abstract: The copper concentrate obtained after separation of a copper ore approximately contains 26 % SiO2,and an excessive SiO2 content can increase subsequent smelting costs.However,increasing the copper grade and reducing the SiO2 content may lower the copper recovery rate.In order to better recover copper and reduce silicon content,experimental research was conducted.The results show that with the increase in regrinding fineness,the SiO2 content decreases,the copper grade increases,and the copper recovery rate first rises and then tends to stabilize.Under the conditions of grinding fineness -0.074 mm accounting for 75 % and regrinding fineness -0.023 mm accounting for 85 %,adopting a closed-circuit test process of one roughing,three cleaning,and three scavenging,a copper concentrate with a grade of 23.40 % and SiO2 content of 12.40 % was obtained,with a copper recovery rate of 89.42 %.