异位土壤淋洗技术修复污染场地的分析--某重金属污染场地土壤修复方案设计

Analysis of remediation of contaminated site by ex-situ soil leaching technology--soil remediation plan design for a heavy metal contaminated site

某地块历史上主要为金属铸造厂,经场地调查与人体健康风险评估确定地块内的土壤受多种重金属污染,污染深度约为2m。该案例结合地块污染情况、场地规划、修复成本与周期、安全性与环境友好度等方面进行修复技术综合比选,选择异位土壤淋洗作为本地块的修复技术。结合小试实验结果进行修复工程实施的深化设计,选择柠檬酸溶液作为淋洗剂,同时确定了土水比、淋洗时间、淋洗次数等关键工艺参数,并对修复过程中的环境管理提出了相关要求。

A certain plot was mainly a metal foundry in history. After site investigation and human health risk assessment, it was determined that the soil in the plot was polluted by various heavy metals, and the pollution depth was about 2 m. In this case, comprehensive comparison and selection of remediation technologies were carried out based on the pollution of the plot, site planning, remediation cost and cycle, safety and environmental friendliness, and selected ex-situ soil leaching as the remediation technology for the local plot. In combination with the results of small-scale experiments, the deepening design of the implementation of the restoration project was carried out, the citric acid solution was selected as the eluent, and the key process parameters such as soil-water ratio, leaching time, and leaching times were determined, and the related requirements for environmental management in the restoration process was proposed.