废铁屑修复汞污染土壤的实验研究  

Laboratory study on remediation of mercury contaminated soil by iron chips

作　　者：张瑞华[1] 孙红文[2] 燕启社[2] 孙会芳[2] 

机构地区：[1]天津科技大学理学院,天津300457 [2]南开大学环境科学与工程学院,天津300071

出　　处：《生态环境》2007年第2期437-441,共5页Ecology and Environmnet

基　　金：天津科技大学基金项目(20040220)

摘　　要：应用工厂废弃物—铁屑做原料,探讨不同铁屑投加量对修复不同土壤类型、不同程度汞污染土壤的能力,并与修复水体汞污染作了对比;另外,首次将淋滤法与国际上新兴的土壤、地下水修复技术-PRB技术结合,研究其修复土壤汞污染的效果。结果表明,废铁屑可很快去除水体中的汞,去除率可达93%;在铁屑存在下,能一定程度预防和修复土壤汞污染,在相同水体汞污染程度条件下,时间是影响土壤汞污染程度的主要因素;在CaCl2淋洗液作用下的模拟PRB实验中,土壤有效汞含量降低,同时淋洗液中汞质量浓度低于1μg·L-1。因此,用废铁屑能有效预防和修复土壤汞污染,且将淋滤法与PRB技术联用,与将铁屑直接撒入土壤中相比效果好得多,且不会引起后续的水体二次污染,是一种很有应用潜力、值得深入研究的土壤修复方法。With the heavy metal contaminated soil increasing, the requirement ofremediation and control technology becomes urgent. Although iron chips has been used widely as a soil amender and as an active material of permeable reactive barrier （PRB）, there are few reports for remedy heavy metal contaminated soil especially for mercury contaminated soil. In this paper, the remediation of mercury contaminated soil by waste iron chips is studied, and the effects of the iron and soil ratio, the type of soil and the contamination degree are discussed. In addition, for the purpose of providing a new way to control and remedy mercury contaminated soil, flushing and PRB, which is a new remediation technology of soil and groundwater, are combined to remedy mercury contaminated soil for the first time. The results indicates that 93% of the mercury in water can be removed quickly by iron chips, with the presence of iron chips, the soil can be remedied or be prevented from contamination to a certainty degree, and time is the primary factor for soil contamination. The combination of flushing and PRB experiment indicates that the soil available mercury has been reduced and the mercury concentration in the filter solution has become less than 1 μg·L^-1. So iron chips can prevent and remedy mercury contaminated soil effectively, the combination of flushing and PRB is a better pattern to remedy mercury contaminated soil than direct scattering iron chips into soil, and it is without second pollution for water system, hence it is a worth while study and a potential technology of soil remediation.

关 键 词：铁屑 汞 土壤污染 土壤修复 重金属污染 

分 类 号：X53[环境科学与工程—环境工程]