甘肃某难选金铜氧化矿金含量为4.83 g/t，铜含量为1.18%，铜氧化率高达95.87%。铜矿物以难选的硅孔雀石为主，且与脉石矿物关系密切，金与铜矿物呈伴生关系。对原矿工艺矿物学进行了系统的研究，分析了尾矿中铜、金损失的原因。在磨矿细度为-74 μm占80%，Na₂S作硫化剂，CuSO₄作活化剂，丁基黄药、羟肟酸和25号黑药作捕收剂的条件下，采用一次粗选，四次扫选，粗精矿再磨后三次精选硫化浮选工艺流程，可获得金品位为86.65 g/t、金回收率为89.11%，铜品位为16.93%、铜回收率为71.92%，银品位为216.24 g/t、银回收率为87.26%的金铜精矿。金铜精矿可采用热压预氧化—无氰化工艺流程回收金铜，该选冶流程可为金铜氧化矿的开发利用提供借鉴。

Silicon malachite is an extremely refractory copper oxide mineral，and the focus of chrysocolla flotation research is the development of new reagents.However， the selectivity and price factors of new pharmaceuticals restrict their industrial applications.In order to improve the flotation index under the premise of using conventional flotation reagents， it is very important to conduct process mineralogy research on refractory copper oxide ore.A refractory gold-copper oxide ores in Gansu Province contains Au 4.83 g/t and Cu 1.18%. The oxidation rate of Cu is as high as 95.87%.The copper minerals are mainly chrysocolla， which is difficult to select and closely related to gangue minerals.Gold is associated with copper minerals.Based on the study of mineralogy of raw ore process， the causes of copper and gold losses in tailings were analyzed and discussed.Sulfide flotation was adopted.After grinding，the products with fineness less than 74 μm accounted for 80%.Under the conditions of sodium sulfide as curing reagent， copper sulfate as activator， butyl xanthate， hydroxamic acid and No.25 dithiophosphate as collector， the sulfide flotation process adopted is “roughing once，sweeping four times，and regrinding coarse concentrate for three times”.The results show that the gold-copper concentrate with Au grade of 86.65 g/t， Au recovery rate of 89.11%， Cu grade of 16.93%， Cu recovery rate of 71.92%，Ag grade of 216.24 g/t and Ag recovery rate of 87.26% was obtained.Through analysis，it is believed that there are 4 reasons for the loss of copper and gold in tailings.1）The oxidation rate of copper is high， there are many types of copper minerals，and there are differences in floatability，in addition，silicon malachite is the main copper-bearing mineral， and its floatability is not good.2）There is a phenomenon that fine-grained silicon malachite is wrapped in gangue minerals.3） The tailings screening analysis shows that the copper lost in the tailings is of fine grade，therefore， the loss of this part of copper in the tailings is a reasonable loss.4）The gold phase analysis results show that the distribution rate of silicate-coated gold and carbonate-coated gold in the tailings is 76.38%， and the gold lost in the tailings is mainly wrapped in veins stone minerals.Gold-copper concentrates can be pre-oxidized by hot-pressing and non-cyanide to recover gold and copper.This smelting process can provide a certain reference for the development and utilization of gold-copper oxide copper mine.