中高温混合菌浸出永平低品位铜矿石的研究

采用包括中高温嗜热铁质菌、喜温嗜酸硫杆菌和嗜热硫氧化硫化杆菌的混合菌群在45℃条件下浸出永平低品位铜矿石,并对矿浆浓度、转速和pH值等工艺因素进行了优化,在最佳浸出条件下对混合菌的浸出行为进行了研究。结果表明:该混合菌群在矿浆浓度150 g/L、转速190 r/min、pH=2.0时,浸出第6 d时铜的浸出率达到94.26%,浸出第24 d铜浸出率达到99.79%。研究还发现中高温混合菌可以有效消除钝化膜的生成,影响浸出率的主要因素是矿浆浓度。

Study on Bioleaching of Low-grade Copper Ore by Moderate Thermophilic Bacterial Mixture

The mixed culture including ferroplasma thermophilium,acidithiobacillus caldus and sulfobacillus thermosulfidooxidans was used to bioleach the low-grade copper ore in Yongping Copper Mine at 45 ℃.The orthogonal design was performed to optimize bioleaching condition,such as initial pulp density,rotating speed and pH value.Results showed that the bioleaching rate could reach 94.26% on the sixth day and 99.79% on the twenty-fourth day with initial pulp density of 150 g/L,rotating speed of 190 r/min and pH value of 2.0.It is also found that the mixed culture can effectively prevent the formation of passivation layer and pulp density is the main factor influencing the leaching rate.