复合型高锰酸钾缓释体原位修复土壤中三氯乙烯的中试实验

采用熔化成型法,以环境友好型材料石蜡和硅砂为复合材料制备复合型高锰酸钾缓释体(CRPCs).将制备的缓释体用于渗透反应墙(PRB),通过小型砂槽实验比较缓释体在反应墙中横向、竖直放置对高锰酸钾传质的影响;通过中试砂槽实验研究在连续进水条件下,缓释体在平行于水流和垂直于水流方向上对三氯乙烯(TCE)的去除效果.结果表明:横向放置比垂直放置更有利于复合型高锰酸钾缓释体中活性组分在土壤中的均匀传质;在横向放置渗透反应器中,平行水流对TCE的去除效果稍好于垂直水流,但不论是平行水流还是垂直水流放置,最终出水均未检出TCE.通过25 d的连续进水实验发现:各取样点的去除效果均维持在高去除率,说明复合型高锰酸钾缓释剂可有效地去除土壤中的TCE污染.

Pilot-Scale In-Situ Remediation of TCE in Soil by Controlled-Release Potassium Permanganate Composites

The controlled-release potassium permanganate composites(CRPCs)mixed with paraffin and silica sand were prepared by melting and cooling method. CRPCs were used in permeable reactive barrier(PRB)and the emplace ways of CRPCs in permeable reactive barrier were compared. The experimental results show: CRPCs in horizontal placement could facilitate KMnO₄ transportation more evenly than those in vertical placement. In PRB with horizontal placement of CRPCs, trichloroethylene(TCE)is degraded more effectively in horizontal influent than that in vertical influent, however TCE in effluent doesn’t detected in both horizontal and vertical influent. After running 25 days, TCE removal efficiency > 99%, which indicates that CRPCs obtained by this method could be applied in the remediation of TCE contamination in soil with easy operation and low cost.