铬污染土壤的还原稳定化修复  

Experimental research onstabilization remediation of chromium contaminated soil

作　　者：张辉[1] 付融冰[2] 郭小品[1] 宋召凤 陈小华[1] 

机构地区：[1]上海市环境科学研究院,上海200233 [2]环境科学与工程学院,污染控制与资源化研究国家重点实验室,同济大学,上海200092

出　　处：《环境工程学报》2017年第11期6163-6168,共6页Chinese Journal of Environmental Engineering

基　　金：上海市自然科学基金资助项目(07ZR14090);上海市环保科研重大项目(沪环科(2013-04));上海市环保科研青年基金项目(沪环科(2015-105));上海领军人才项目(011)

摘　　要：以湖南某工业场地的铬污染土壤为修复对象,投加不同比例的Fe SO4·7H2O、Fe SO4·7H2O和Ca(OH)2混合物及Na HSO3,通过测定土壤及浸出液中六价铬、总铬以及铬的形态,比较3种稳定剂对该污染土壤的还原稳定化作用。结果表明,Fe SO4·7H2O和Na HSO3对铬污染土壤的还原稳定效果都较好,可以有效还原土壤中六价铬并能降低土壤中总铬的浸出浓度。当Fe SO4·7H2O投加量为2%时,土壤六价铬和总铬浸出浓度降幅分别达到99.0%和57.5%;当Na HSO3投加量为0.8%时,六价铬和总铬浸出浓度降幅分别达到97.7%和42.2%,与前二者相比,Fe SO4·7H2O和Ca(OH)2混合物还原稳定化效果较差。投加Fe SO4·7H2O能够将土壤中活性大的可交换态和碳酸盐态铬转化为稳定的有机态和残渣态铬;而Na HSO3主要将可交换态和碳酸盐态铬转化为相对稳定的铁锰氧化态铬,其稳定化效果要差于Fe SO4·7H2O。Different proportions of FeSO4 ·7H2O, mixture of FeSO4· 7H2O and Ca（OH）2 and NaHSO3, were added in the chromium polluted soil collected from an industrial area in Hunan Province. The efficiencies of 3 different stabilizers on the remediation of chromium contaminated soil were compared based on the contents of hexavalent chromium, total chromium and chromium of different forms in soil and leaching liquids. The results show that both FeSO4 ~ 7H2Oand NaHSO3can effectively reduce the leaching concentration of hexavalent chromi- um and total chromium. When dosing quantity of FeSO4 · 7H2O was 2% , reduction of hexavalent chromium and total chromium in the leaching liquid of the contaminated soil were 99.0% and 57.5% , respectively. When do- sing quantity of NaHSO3 was O. 8% , reduction of hexavalent chromium and total chromium in the leaching liq- uids of the contaminated soil were 97.7% and 42.2% , respectively. Compared with the former two stabilizers, stabilization effect of the mixture of FeSO4·7H2O and Ca（OH）2was poor. FeSO4·7H/O can transform the ac- tive exchangeable and carbonate chromium to the stable organic and residual chromium; NaHSO3 can mainly transform exchangeable and carbonate chromium to the relatively stable manganese-iron combination state, which is the reason why its stabilization efficiency is worse than FeSO4·7H2O.

关 键 词：铬 六价铬 稳定化 重金属形态 

分 类 号：X703.5[环境科学与工程—环境工程]