铅污染土壤电动淋洗联合异位修复实验

电动修复技术是一种非常具有潜力的重金属污染土壤修复技术.实验针对某工业污染场地中的铅污染土壤,采用电动和淋洗相结合的方法对其进行修复;采用高电压梯度直流电场（40.3 V/cm）以提高土壤温度,促进铅的解析,同时提高离子的电迁移速度;解析后的铅离子在直流电场作用下从上往下迁移,随淋洗液流出,在微负压条件下进入收集瓶;实验通电时间80 min,耗电337 kWh/m3,土壤中的铅浓度由原来的410±16 mg/kg降至252± 10 mg/kg,低于重庆市土壤健康风险评估阈值,实现了修复目标;结果显示淋洗可以有效阻止铅在阴极聚集形成聚焦带,提高修复效果.

Electrokinetic and flushing jointed ex-situ remediation of Pb-contaminated soil

The electrokinetic remediation contaminated soil. This research combined the （EKR） is a promising technique which is effective on the metal- EKR with a flushing method to remediate the lead-contaminated soil excavated from a factory site. This experiment used a high potential gradient direct electric field （40.3V/cm） to raise the soil temperature to promote the desorption and migration of lead ions. The desorbed lead ions migrated from top to bottom under the direct electric field and flew into the collection bottle with the eluent in a condition of slight negative pressure. The power consumption was 337 kWh/m3 in 80 minutes. The soil lead concentration decreased from 410±16 mg/kg to 252±10 mg/kg, below the Chongqing soil health risk assessment threshold, meeting the remediation demand. Meanwhile, the experiment result also shows that flushing method also effectively eliminated the focusing girdle accumulated and formed in the soil near the cathode to improve the remediation effect