从炼铜厂炉渣中回收铜铁的研究

Recovery of copper and iron in the converter slag from a copper smelter

针对铜转炉渣中铜铁硅矿物紧密共生、呈细粒不均匀嵌布及渣硬度高、难磨的特点,进行了多种磨矿与选别流程组合的对比试验,最后选用磨矿(-0.043mm79.6％)-浮选-磁选-浮选中矿与磁性矿合并再磨(-0.040mm 99.32％)-再浮-再磁的阶段磨矿阶段选别的流程,其中第一段磁选精矿再磨是铁硅单体分离获得合格铁精矿的关键,在转炉渣含铜1.58％(硫化铜和金属铜占78.68％)、含铁53.54％(磁性氧化铁占28.53％)的情况下,获得铜精矿品位19.82％,回收率85.48％的选铜指标,同时综合回收了渣中磁性氧化铁,得到铁品位62.525％、回收率35.02％、含SiO_29.94％的合格铁精矿。

In the light of the close intergrowth and fine uneven dissemination of copper, iron, and silicon minerals in copper converter slag as well as the high hardness and difficult re- grinding of the slag, grinding and separating under different grinding fineness are tested. Fi- nally a stage grinding and stage separation flowsheet, which comprises grinding (--0. 043 mm up to 79. 6%), flotation, magnetic separation, regrinding for flotation middling and magnetic mineral together (--0. 040 mm up to 99. 32%), re--flotation, and re--rnagnetic sepa- ration, is adopted to treat the slag. Regrinding for magnetic rough concentrate is important for separation of iron and silicon. The feed of the converter slag contains 1. 58% Cu, of which copper sulphide, and copper metal amounts to 78. 68%, and 53. 54% Fe, of which magnetic iron oxide amounts to 28. 53%. As a result, the grade of copper concentrate is 19. 82% with the recovery of 85. 48%. In the meantime, magnetic iron oxide is also recov- ered. Iron concentrate contains 62. 525% Fe and 9. 94% SiO_2, with the iron recovery being 35. 02%.