固定化菌体吸附矿山废水中重金属的研究

研究了固定化菌体对矿山废水重金属的吸附性能.结果表明,固定化菌体对重金属有良好的富集性能,投加15g·L-1的固定化菌体,对100 mg·L-1 Cu、50 mg·L-1 Zn的去除率分别可达94.4%、80.6%.废水pH、菌体投加量对固定化菌体的处理效果影响较大,其最佳值分别为3.5、15 g·L-1.经4轮吸附-解吸循环实验,显示固定化菌体可重复利用3次,固定化菌体在使用第3次时,对100 mg·L-1 Cu、50mg·L-1 Zn的去除率分别为67.4%、46.5%.用固定化菌体的流化床工艺处理废水最佳参数为曝气量4.02 L·min-1,处理2h.用固定化菌体的流化床工艺处理矿山废水取得了较好的效果,对于浓度低于10 mg·L-1的重金属,去除率达到了100%,对浓度为579.2 mg·L-1 Fe的去除率也达到了56.6%,表明该工艺具有较好的工业化前景.

Biosorption of heavy metals from mine wastewater by immobilized bacteria

The utility of immobilized bacteria as a biosorbent for heavy metals from mine wastewater was investigated. The experimental results showed that heavy metals could be efficiently accumulated by the immobilized bacteria with removal efficiencies of 94.4% and 80.6% for 100 mg·L^-1 Cu and 50mg·L^-1 Zn, respectively, at a strain dose of 15g·L^-1. The biosorption efficiency was strongly influenced by the pHof the mine wastewater (optimal pH3.5) and strain dose (optimal value 15 g·L^-1). Immobilized bacteria regeneration studies were carried out over four sorption-desorption cycles. Removal efficiencies of 67.4% and 46.5% for 100 mg·L^-1 Cu and 50mg·L^-1 Zn were still attained in the third cycle. An immobilized bacteria based fluidized bed technique was developed to handle the mine wastewater. Optimal operation conditions for the fluidized bed were 4.02L·min^-1 aeration and 2h treatment time. The immobilized bacteria fluidized bed effectively treated mine wastewater, removing 100% of all heavy metals with concentrations lower than 10mg·L^-1 and 56.6% of Fe, initially present at 579.2mg·L^-1, thus this process is a promising technique for future applications.