生物淋滤电动修复湖泊底泥中的铬

Hybrid Technology of Bioleaching and Electrokinetics to Remediate Chromium Contaminated Sediments

该文采用生物淋滤电动复合技术修复底泥,经生物淋滤后底泥中铬形态发生了改变,可交换离子态、碳酸盐结合态的铬含量比例明显增加,而铁锰氧化物结合态、硫化物及有机结合态以及残渣态的比例含量明显下降(可为电动修复底泥时铬的迁移提供有利条件)。单纯电动修复铬的去除率为32.6%,单纯生物淋滤铬的去除率为25.1%,淋滤去除率与底泥的pH值和氧化还原电位紧密相关。经生物淋滤电动复合处理后,铬的去除总量可达53.4%。生物淋滤电动复合技术对可交换的离子态、碳酸盐结合态、硫化物及有机结合态的铬去除率较高,特别是对碳酸盐结合态的铬去除率达到61.1%。实验表明电动生物淋滤技术具有协同作用,适合湖泊底泥铬污染治理。

Sediment pollution is quite a serious problem in the whole world.Hybrid technology of bioleaching and electrokinetics was adopted to remediate the polluted sediments.The speciation of chromium in sediments had significant changes during bioleaching remediation.The exchangeable and carbonate-bound portion were increased significantly,whereas Fe/Mn oxide-bound,organic matter/sulfide-bound or residual fraction were decreased significantly(It can provide favorable conditions for the migration of chromium during electrokinetics remediation).The remove rate of chromium was 32.6%by electrokinetic remediation method.The leaching rate of chromium in sediment was 25.1%,which was closely related to pH value and redox potential of sediments.In the comparison of bioleaching-electrokinetic and electrokinetic remediation,the average removal rate of total chromium was up to 53.4%after bioleaching-electrokinetic remediation.Experiments show that the hybrid technology of bioleaching and electrokinetic remediation has synergistic effects and is suitable for chromium pollution control in sediments.