蓝辉铜矿的细菌氧化浸出研究

Bioleaching of Digenite Concentrate

研究了紫金山铜矿中主要目的矿物之一的蓝辉铜矿细菌浸出的过程和影响因素,考察了蓝辉铜矿纯矿物的浸出特性。实验室条件下细菌浸出蓝辉铜矿纯矿物的适宜参数为:接种量50%;培养基中Fe2+氧化量为60%。20 d浸出周期内蓝辉铜矿浸出率可达80%以上。通过向纯矿物浸出体系中添加黄铁矿探讨其强化浸出效果。结果表明:以1∶2或1∶1重量比添加黄铁矿能明显加快蓝辉铜矿的细菌浸出速率。通过对蓝辉铜矿和黄铁矿在浸出介质中静电位的测定表明,添加黄铁矿后能在浸出体系中形成较强的原电池效应,促进目的矿物的溶解。

The influential factors of bioleaching of digenite concentrate collected from Zijinshan copper mine with bacteria were investigated.The optimal parameters of bioleaching of digenite concentrate were determined,which were concentration of inoculum 50% and oxidation ratio of Fe2＋ in culture 60%.Within 20 d,the copper recovery rate reached above 80%.In order to enhance the redox potential level in the process of bioleaching,pyrite was added in the leaching solution.The results showed that the addition of pure pyrite could effectively raise the Eh of bioleaching process.It could quicken the leaching process of digenite and enhance the final copper recovery through addition of pyrite by 1∶1 or 1∶2 ratio of digenite concentrate to pyrite.Electrostatic potential of digenite and pyrite were determined,which indicated that galvanic cell was composed by the copper sulfide and pyrite while the pyrite was added in the leaching solution,and the copper sulfide mineral was accelerated to be dissolved.