水资源与水工程学报2023，Vol.34Issue(6)：210-219,10.DOI:10.11705/j.issn.1672-643X.2023.06.25
黄土中铜铅金属的电动迁移及强化去除机理研究
Electrokinetic remediation of copper and lead contaminated Loess and enhancement mechanisms of combined methods
摘要
Abstract
This study focuses on the use of electrokinetic remediation technology to investigate the migra-tion of copper and lead metal ions in artificially prepared copper and lead contaminated loess.The tech-nology chosen has a higher cost performance and lower risk of secondary pollution.The study also exam-ines the impact of single-component remediation methods such as electrode materials,cation exchange membrane and acid pretreatment on various factors such as current,electroosmotic flow,pH,electrical conductivity,removal efficiency and ion occurrence during the process of electrokinetic remediation.The findings revealled the electrokinetic remediation mechanism of the strengthening methods and further clar-ified the strengthening mechanism of the combination of the three remediation methods.According to the results,the electrokinetic geosynthetics(EKG)electrodes have a higher current than graphite electrodes,while being able to rapidly release more hydrogen ions and hydroxide ions.An acidic environment is pro-vided near the anode to promote the desorption and migration of more heavy metal ions,thereby improving the remediation efficiency,whereas precipitation near the cathode results in lower removal efficiency for this part.The use of cation exchange membrane can improve soil pH regulation near the cathode and aid in the desorption of metal ions.The polarization resulting from concentration differences across the cation exchange membrane and precipitation on its surface can substantially decrease the current and electroos-motic flow,thereby limiting the increase in removal efficiency.The pH value of polluted loess sample can be reduced through acid pretreatment.This leads to a decrease in the original negative charge on the sur-face of clay minerals,hydrated oxides,and organic matter in the loess,and can even make it positive.Such a change is beneficial for the early desorption of heavy metals,and greatly improves the electrical conductivity,therefore enhance the current and electroosmotic flow,which is comparable to the reinfor-cing effect of using a cation exchange membrane,so it is a cost-effective approach to strengthening.The combined use of EKG electrodes,cation exchange membranes and acid pretreatment can effectively en-hance their individual mechanisms and advantages.This combination can increase current flow,lower the pH value of loess,prevent heavy metal precipitation near the cathode,promote the desorption and migra-tion of heavy metal ions and ultimately enhance the electrokinetic remediation removal efficiency.This study further illustrates the effectiveness of electrokinetic removal of heavy metal in copper and lead con-taminated loess and the feasibility of the proposed remediation methods.关键词
电动修复/铜铅重金属污染/电动土工合成材料(EKG)/酸预处理/黄土Key words
electrokinetic remediation/contamination of copper and lead/electrokinetic geosynthetics(EKG)/acid pretreatment/loess分类
资源环境引用本文复制引用
王艺涵,胡文乐,郑文杰,文少杰..黄土中铜铅金属的电动迁移及强化去除机理研究[J].水资源与水工程学报,2023,34(6):210-219,10.基金项目
中共中组部"国家海外高层次人才引进计划"青年项目(2019) （2019）
创新人才推进计划-科技创新团队项目(2020TD-005) （2020TD-005）
