PRB技术对地下水中重金属离子的处理研究  

Removal of heavy metal ions from groundwater by permeable reactive barrier

作　　者：杜连柱[1] 张兰英[1] 王立东[2] 房芳[1] 

机构地区：[1]吉林大学环境与资源学院,吉林长春130026 [2]沈阳建筑大学市政与环境工程学院,辽宁沈阳110168

出　　处：《环境污染与防治》2007年第8期578-582,共5页Environmental Pollution & Control

基　　金：国家"973"计划项目(No.2004CB418505)

摘　　要：实验模拟地下环境,以受重金属离子Pb(Ⅱ)、As(Ⅲ)、Cd(Ⅱ)、Cr(Ⅵ)、Fe(Ⅱ)和总Mn污染的地下水为研究对象,利用还原铁粉、铸铁粉、铸铁粉与颗粒活性炭的混合物为可渗透反应墙(PRB)的主要介质,石英砂为辅助介质,设计了3种反应器。在有效孔隙率为60%～65%、水力停留时间为12.0～14.4h的条件下,考察其对污染物的去除效果。结果表明:3种反应器对Pb(Ⅱ)、As(Ⅲ)、Cd(Ⅱ)、Cr(Ⅵ)均有较高的去除效果,去除率达98%以上;总Mn的去除率分别达98%、89%和66%;Fe(Ⅱ)的去除率分别达83%、56%和49%。考察了3种反应器内pH、Eh、DO的关系及对重金属离子去除效果的影响,分析了污染物的去除机理。综合考虑处理效果与成本,笔者认为以铸铁粉与石英砂的混合物为PRB的反应介质,应用PRB技术原位处理受上述重金属离子污染的地下水是可行的。Three permeable reactive barrier（PRB）reactors, filled with a reactive media and quartz sand, were employed to remove heavy metals ions Pb（ Ⅱ ）, As（ Ⅲ ）, Cd（ Ⅱ ）, Cr（ Ⅶ ）, Fe（ Ⅱ） and total Mn from a groundwater sample. These three PRB reactors tested were filled with zero-valent iron powder/sand mixture, cast iron powder/ sand mixture and mixture of sand,cast iron powder and granular activated carbon, respectively. Operating under a void ratio of 60% to 65% and a hydraulic retention time of 12.0 to 14.4 h,the PRB reactors accomplished more than 98% of heavy metals ions removal,while about 98% ,89% ,66% of total Mn and 83% ,56% ,49% of Fe（Ⅱ ） were removed respectively. The removal mechanisms and the effect of pH,redox potential and dissolved oxygen were discussed and compared for the three reactors. Additional experiments were proposed to ensure the PRB process would be cost effective for removing heavy metals from groundwater.

关 键 词：可渗透反应墙(PRB) 重金属离子 铸铁粉 去除机理 

分 类 号：X523[环境科学与工程—环境工程]