电动力学可渗透反应屏障耦合修复Cd污染土壤的试验研究  

Experimental study on remediation of Cd-contaminated soil by electrokinetic permeable reaction barrier coupling

作　　者：柴肇云[1] 李健[1] 贺利霞 闫珂 李亚男 CHAI Zhaoyun;LI Jian;HE Lixia;YAN Ke;LI Yanan(Key Laboratory of In-Situ Property-Improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan Shanxi 030024,China;College of Civil Engineering,Taiyuan University of Technology,Taiyuan Shanxi 030024,China)

机构地区：[1]太原理工大学原位改性采矿教育部重点实验室,山西太原030024 [2]太原理工大学土木学院,山西太原030024

出　　处：《矿业科学学报》2025年第2期338-350,共13页Journal of Mining Science and Technology

基　　金：国家自然科学基金(52274091)。

摘　　要：电动力学可渗透反应屏障耦合修复技术能有效去除煤矿区污染土壤中的重金属离子。以Cd污染土壤为研究对象,开展EK-PRB耦合修复的物理模拟试验,系统研究电解液和土壤pH值、Cd^(2+)去除率、电流以及总电能消耗等的演化规律。结果表明:修复过程中电解液pH值和电流呈周期性变化,周期内阳极pH值降低,阴极pH升高,电流先增后降;修复后污染土壤pH值和Cd^(2+)富集指数从阳极至阴极依次升高;柠檬酸+NaCl混合液作电解液时,电流和Cd^(2+)去除率显著提高,修复效率最佳;蒙脱石作PRB活性填充材料可有效降低阴极电解产生的OH^(-)浓度和迁移速率,Cd^(2+)去除率更高,电能消耗更低,修复效率最佳;电压梯度与Cd^(2+)去除率和电能消耗正相关。综合考虑Cd^(2+)去除率、电能消耗以及修复成本等因素,电压梯度为2.5 V/cm时修复效率最佳。Coupled remediation by electrodynamic permeable reaction barrier(EK-PRB)could effectively remove heavy metal ions from contaminated soil in coal mine areas as this technology combines the advantages of both electrokinetic remediation and permeable reaction barrier.Taking Cd-contaminated soil as the research object,this study conducted physical simulation experiment of EK-PRB coupled remediation to investigate the evolution patterns of pH value of electrolyte and soil,Cd^(2+)removal efficiency,current and total electric energy consumption in coupled remediation.We found that the pH value of the electrolyte and current exhibited cyclic variations during the remediation process:the pH value of anode decreased while that of cathode increased,the current first increased and then decreased within the cycle.After remediation,the pH value and Cd^(2+)enrichment index of contaminated soil increased successively from anode to cathode.When a mixture of citric acid and NaCl was used as elec-trolyte,Cd^(2+)removal efficiency and current increased significantly,demonstrating maximum remedia-tion efficiency.Montmorillonite as PRB active filling material could effectively reduce the OH^(-)concen-tration and migration rate produced by cathodic electrolysis,showing higher removal efficiency of Cd^(2+),lower electric energy consumption,and maximum remediation efficiency.The voltage gradient is posi-tively correlated with Cd^(2+)removal efficiency and electric energy consumption.Given factors such as Cd^(2+)removal efficiency,electric energy consumption and cost-effectiveness,the remediation efficiency reaches its maximum when the voltage gradient is 2.5 V/cm.

关 键 词：电动力学 可渗透反应屏障 重金属 修复效果 吸附机制 

分 类 号：X752[环境科学与工程—环境工程] X171.1