湖南某金矿石选矿试验研究

Beneficiation Experimental Study on a Gold Ore in Hunan

湖南某金矿石Au品位为2.41 g/t,主要载金矿物为毒砂和黄铁矿,主要脉石矿物有高岭土、绿泥石等,金矿物的嵌布粒度极微细,单体金粒量极少,大部分金粒与毒砂连生或包含于毒砂中,少部分金粒包含于黄铁矿中。为确定矿石的适宜选别工艺进行了选矿试验,结果表明,试样在磨矿细度为-0.074 mm78%的情况下采用摇床重选,重选中矿在再磨细度为-0.074 mm 87.77%情况下采用1粗2精、中矿顺序返回闭路浮选流程处理,最终获得了产率为1.84%、Au品位为111.45 g/t、回收率为85.05%的金精矿,金精矿质量满足含毒砂Ⅰ级品质量要求,较好地实现了金的回收。

The Au grade of a gold ore in Hunan is 2.41 g/t,the main gold-bearing minerals are arsenopyrite and pyrite,the main gangue minerals are kaolin,chlorite and so on.The disseminated grain size of gold minerals is very fine,and the amount of single gold particles is very small.Most gold particles are connected with arsenopyrite or contained in arsenopyrite,and a small part of gold particles are contained in pyrite.The beneficiation tests were carried out to determine the suitable separation technology of the ore.The results showed that gravity separation by shaking was applied for the samples when the grinding fineness is-0.074 mm accounting for 78%.Then,the middlings from gravity separation was processed by the closed-circuit flotation process of one roughing and two cleaning and middlings return in sequence when the grinding fineness is-0.074 mm accounting for 87.77%.Finally,the gold concentrate with yield of 1.84%,Au grade of 111.45 g/t and recovery rate of 85.05%was obtained.The quality of gold concentrate met the quality requirements of first grade products containing arsenopyrite,and the gold recovery was well realized.