某难选次生富集带含铜硫铁矿综合回收试验研究

Experimental Study on Comprehensive Recovery of Copper-bearing Pyrite in a Refractory Secondary Enrichment Zone

某次生富集带硫铁矿含S 28.73%、Cu 0.61%。该矿金属矿物以黄铁矿和白铁矿为主,含少量的铜蓝、辉铜矿、蓝辉铜矿、黄铜矿、黝铜矿、斑铜矿等含铜矿物;脉石矿物以石英和方解石为主。对该矿进行铜物相分析,铜矿物以硫酸铜为主,其次为次生硫化铜及少量原生硫化铜。硫酸铜遇水易溶解,产生大量铜离子,在浮选过程中会活化黄铁矿造成铜硫分离困难。同时次生铜矿物不仅易于过磨而增加铜在尾矿中的损失,而且容易罩盖在黄铁矿表面造成铜硫分离更加复杂。为了更好地回收该矿中的铜,试验采取水洗+铜优先浮选的方案,通过水洗优先回收硫酸铜中的铜,再对水洗浸渣进行铜优先浮选,回收硫化铜矿物。研究结果表明:(1)对该矿进行水洗试验,能有效地回收硫酸铜中的铜,铜回收率为47.30%;(2)水洗浸渣在磨矿细度为-0.074 mm占70%、石灰用量为3 000 g/t、硫化钠用量为3 000 g/t、水玻璃用量为3 000 g/t、亚硫酸钠用量为1 800 g/t、BK404用量为30 g/t的条件下,进行闭路浮选流程处理,最终获得铜精矿Cu品位14.45%,Cu回收率46.94%;硫精矿S品位46.10%,S回收率96.22%。通过试验研究,该矿铜硫矿物均得到合理回收,研究结果为该类型铜矿资源的有效回收提供了借鉴。

A pyrite ore which in the secondary enrichment zone contains sulfur of 28. 73% and copper of 0. 61%. The metal minerals of the ore are mainly pyrite and marcasite,and a small amount of copper bearing minerals such as cuprune,chalcoxene,blueschalcoxene,chalcopyrite,tetrahedrite,bornite,etc. The gangue minerals are mainly quartz and calcite. The copper phase analysis shows that copper sulfate is the main copper mineral,followed by secondary copper sulfide and a small amount of primary copper sulfide. Copper sulfate is easily soluble in water,producing a large amount of copper ions,which activates the pyrite in the flotation process and affects the separation effect of copper and sulfur. At the same time,the secondary copper minerals are not only easy to over-grind,which increases the copper lossing in the tailings,but also easy to cover the surface of the pyrite,which makes the separation of copper and sulfur more complicated. In order to better recover the copper in the ore,the experiment adopts the scheme of water washing and copper preferentially flotation. The copper in the copper sulfate is preferentially recovered by water washing,and then copper preferentially flotation is carried out on the leaching slag in water washing to recover the copper sulfide minerals. The results showed that:(1) the copper in copper sulfate can be effectively recovered by washing test,and the copper recovery rate is 47. 30%.(2) In the conditions of grinding fineness of-0. 074 mm accounting for 70%,the dosage of lime of 3 000 g/t,the dosage of sodium sulfide of 3 000 g/t,the dosage of sodium sulfite of 3 000 g/t,the dosage of sodium sulfite of 1 800 g/t,the dosage of BK404 of 30 g/t,the copper grade of the copper concentrate obtained in the closed-circuit flotation section is 14. 45%,and the recovery rate is 46. 94%. The sulphur grade of the sulphur concentrate obtained in the closed-circuit flotation section is 46. 10%,and the recovery rate is 96. 22%. Through the experimental study,the copper and sulfur minerals in this mine have been recovered reasonably,and the research results provide a reference for the effective recovery of this type of copper resources.