用TCLP和形态法评估含磷物质修复铅锌矿污染土壤的效果及其影响因素  

Evaluation of Phosphate-Containing Amendments on Remediation Effect and Influential Factors in a Lead/Zinc Mining Tailings Contaminated Soil Using TCLP and Forms

作　　者：陈建军[1,2] 俞天明[1] 王碧玲 谢正苗[1,2] 

机构地区：[1]杭州电子科技大学环境科学与工程系,杭州310018 [2]浙江大学环境与资源学院,杭州310029 [3]泉州市委办公室,泉州362400

出　　处：《环境科学》2010年第1期185-191,共7页Environmental Science

基　　金：国家自然科学基金项目(40771100);浙江省重大科技专项(2008C13009);环境修复与生态健康教育部重点实验室基金项目(050202)

摘　　要：在温室模拟条件下,以P/Pb摩尔比分别为0、0.6、1.2、1.8、3.0、4.0等6个P水平,进行了含磷物质修复铅锌矿污染土壤的试验.采用毒性淋溶提取法(TCLP)、水溶态和交换态提取法评估了过磷酸钙(SSP)和磷酸二氢钾(MPP)对铅锌矿污染土壤中Pb、Zn的修复效果.结果表明,SSP和MPP都显著(p<0.05)降低土壤交换态和TCLP态Pb含量,降低TCLP态含量的幅度大小顺序是:MPP(66%～93%)>SSP(26%～69%).MPP处理的P水平在0.6、SSP处理的P水平在1.2～1.8区间时,足以把土壤中TCLP Pb的含量降低到国际限制标准(5 mg.L-1)以下.MPP对土壤中Zn的TCLP态含量无显著影响,而SSP在显著降低了交换态含量的同时,微量增加了TCLP态含量,但都远低于国际限制标准(25 mg.L-1).各种形态Zn(TCLP、水溶性、交换态)的含量均与土壤pH显著负相关,说明即使添加了含P物质处理,土壤中Zn的活性主要还是受土壤pH控制.上述结果进一步说明了含P物质具有显著降低铅锌矿污染土壤的环境风险的作用.A pot experiment was conducted to evaluate the effects of phosphate-containing（P） amendments on the toxicity and bioavailability of Pb and Zn in a soil contaminated by mining tailings using toxicity characteristic leaching procedure（TCLP） and water soluble,exchangeable leaching procedures in order to find out the appropriate P application rates to reduce the soil TCLP extractable Pb to below the USA EPA＇s regulatory limit levels.The results showed that TCLP extractable Pb concentrations were significantly decreased by up to 93.3% for MPP treatments and up to 68.5% for SSP treatments after P application.The dose required to reduce leachable Pb below the EPA＇s regulatory limit level was found to be around the molar ratio of vP/Pb = 0.6 for MPP and 1.8 for SSP.It was also found both MPP and SSP could reduce the exchangeable Pb and Zn concentrations that all bio-available Zn forms including water soluble,exchangeable,and TCLP extractable forms in soil were significantly and negatively cor.related to soil pH values,indicating that the content of Zn in the soil was mostly controlled by soil pH value even after P application.These results suggest that P as MPP and SSP could successfully decrease the toxicity and bioavailability of Pb and Zn in the contaminated soil.

关 键 词：毒性淋溶提取法(TCLP) 磷 铅 锌 土壤修复 

分 类 号：X53[环境科学与工程—环境工程]