石灰和粉煤灰固化修复六价铬污染土试验研究  

Experimental Study of Lime and Fly Ash for Solidification Remediation of Hexavalent Chromium Contaminated Soil

作　　者：刘玲[1] 刘海卿[1] 张颖[1] 吴佳欢[1] 薛淋丹 金群林 王袁[1] 

机构地区：[1]辽宁工程技术大学建筑工程学院,阜新123000

出　　处：《硅酸盐通报》2015年第11期3361-3365,共5页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金项目(51304106);辽宁省大学生创新性实验计划项目(201410147051)

摘　　要：为解决受污染土壤中六价铬浸出和渗透到地下水带来的环境污染问题,以沈阳铬渣堆场污染土壤为研究对象,进行石灰和粉煤灰联合修复铬污染土试验研究,分析石灰和粉煤灰不同剂量、养护龄期对污染土六价铬浸出的影响,分析了两者联合修复机理。研究结果表明:在固化修复0.4%Cr(VI)污染土中,组合添加10%~15%生石灰和25%~35%粉煤灰养护28 d有较好效果,浸出液铬离子浓度均在规定界限5 mg·L^(-1)以下;主要修复机理为较高的基质p H值促进了Cr(VI)与粉煤灰表面的物理-化学相互作用,以及生石灰与粉煤灰的火山灰反应。In order to solve the environmental pollution problem arising from the leaching and the seepage of Cr（ Ⅵ ） from soil to groundwater, taking the chromite ore processing residue contaminated soil of Shenyang as a research object, experiments on remediation of lime/fly ash solidified/stabilized Cr（Ⅵ） contaminated soil were conducted. The contrasts of hexavalent chromium concentration in filtrate from leaching experiments of lime/fly ash solidified/stabilized Cr （VI） contaminated soils were discussed in different curing period. The reaction mechanism existing in the repair of the curing agents was analyzed. The result shows that leach ability reduction is effective with synchronous addition 10wt% -15wt% of lime and 25wt%-35wt% of fly ash to soils contaminated with 0. 4wt% of Cr （Ⅵ）, and the leaching concentration of Cr（Ⅵ） is below the limit for chromium of 5 mg/L after 28 d of curing. Pointed out that hydration gel surface adsorption and the formation of metal hydroxide precipitation is the main reason affecting the leaching characteristics of soils. The main repair mechanism is that the physical-chemical interaction with Cr（VI） on pore surface of fly ash and the pozzolanic reactions of lime and fly ash is promoted in a solid matrix with high pH.

关 键 词：六价铬 污染土 地下水污染 土壤修复 稳定化 

分 类 号：X705[环境科学与工程—环境工程]