硫酸盐还原菌修复四川某典型铜矿选冶渣复合重金属污染研究

Study on the Remediation of Composite Heavy Metal Pollution of Slag in a Typical Copper Minein Sichuan Using Sulfate-reducing Bacteria

为实现铜矿选冶渣复合重金属污染的修复治理,以四川某铜矿选冶渣为研究对象,采用硫酸盐还原菌为固化/稳定化微生物,探讨了其生长特性、溶液中重金属离子变化规律及修复效果。结果表明,硫酸盐还原菌在修复铜矿选冶渣时生长迅速,适合作为修复复合重金属污染的微生物;由于铁、锌、铜、铅等重金属活性差异较大,因此其固化效果亦有显著差异;修复30 d时,重金属Cu、Pb、Zn、Fe的最佳接种量分别为5%、10%、15%和15%,生物有效性降低率分别为72.36%、98.37%、43.01%和79.31%;随着固化时间的增加,溶液中重金属离子的浓度先增后减,但并不影响其修复效果。因此,硫酸盐还原菌可同时修复多种重金属离子,有效解决某铜矿选冶渣中铁锌铜铅的复合重金属污染。

In order to realize the remediation and treatment of composite heavy metal pollution of copper ore dressing and smelting slag,this study focuses on a typical copper smelting slag site in Sichuan,China.Sulfate-reducing bacteria(SRB)were employed as the bioremediation agent to investigate their growth characteristics,the variation of heavy metal ions in solution and the remediation effects.The results demonstrate that SRB can proliferate rapidly during the remediation process,making them suitable for the treatment of composite heavy metal pollution.Due to the significant activity differences among heavy metals such as iron,zinc,copper and lead,their stabilization effects also vary considerably.Within 30 days,the optimal inoculation rates for the four heavy metals of Cu、Pb、Zn、Fe were 5%,10%,15%,and 15%,respectively,with the bioavailability reduction rates of 72.36%,98.37%,43.01%and 79.31%.As the stabilization period increased,the concentration of heavy metal ions in the solution initially increased and then decreased,but this did not affect the remediation effect.Therefore,SRB can simulta-neously remediate multiple heavy metals,effectively addressing the composite heavy metal pollution of iron,zinc,copper,and lead in the typical copper smelting slag in Sichuan.