摘要
针对垃圾渗滤液渗漏严重威胁地下水水质的问题,以过碳酸钠(sodium percarbonate,SPC)为固体氧化剂来构建地下水的原位修复技术,采用单因素法,以受污染的高COD地下水为处理对象,通过实验研究了n(SPC):n(FeSO_(4)·7H_(2)O)、药剂投加量、反应时间对SPC/Fe^(2+)体系去除COD的影响和SPC/Fe^(2+)体系的反应机理。结果表明:n(SPC):n(FeSO_(4)·7H_(2)O)和SPC的投加量显著影响COD的去除效能;在初始pH值为7.22、 n(SPC):n(FeSO_(4)·7H_(2)O)=1:2.75、 SPC投加量为48 mmol·L^(-1)以及反应30 min的最佳实验条件下,COD的去除率可达82.09%;SPC/Fe^(2+)体系通过降解类蛋白有机物和腐殖酸实现高COD地下水的有效处理,主要活性物种HO·能够有效减小腐殖质分子量及其分子间聚合度,同时降低芳香性构化程度。由此可知,SPC作为固体氧化剂有应用于实际渗透性反应格栅(PRB)工程的潜力。本研究结果可为PRB在修复受垃圾渗滤液污染地下水的实际工程提供参考。
Landfill leachate leakage is a serious threat to groundwater quality. Sodium percarbonate(SPC) was used as a type of solid oxidant to build the in-situ remediation technology of groundwater. The single factor method was used to study the remediation test on the treatment object: the polluted groundwater with high COD.The effects of n(SPC):n(FeSO_(4)·7H_(2)O), chemical dosage and reaction time on COD removal and the corresponding reaction mechanism of SPC/Fe^(2+)system were studied. The results showed that n(SPC):n(FeSO_(4)·7H_(2)O) and SPC dosages significantly affected the removal efficiency of COD;under the optimal experimental conditions of initial pH 7.22, n(SPC):n(FeSO_(4)·7H_(2)O) of 1:2.75, SPC dosage of48 mmol·L^(-1)and reaction time of 30 min, the removal rate of COD could reach 82.09%;the SPC/Fe^(2+)system achieved the effective treatment of high-COD groundwater by degrading proteinoid organics and humic acid.The main active species HO· could effectively decrease the molecular weight of humus and its intermolecular polymerization degree, as well as the degree of aromatization. SPC as solid oxidant had a potential for its application in permeable reactive barrier(PRB) engineering. The results of this study can provide a reference for the practical engineering of PRB in the remediation of groundwater contaminated by landfill leachate.
作者
张楠
刘忠义
向鑫
王佳林
张洪志
刘菲
ZHANG Nan;LIU Zhongyi;XIANG Xin;WANG Jialin;ZHANG Hongzhi;LIU Fei(Beijing Key Laboratory of Water Resources and Environmental Engineering,School of Water Resources and Environment,China University of Geosciences(Beijing),Beijing 100083,China;Heilongjiang Institute of Ecological Geological Survey,Harbin 150056,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2023年第1期103-112,共10页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金面上基金资助项目(42072275)。
关键词
地下水
垃圾渗滤液
过碳酸钠
化学耗氧量
groundwater
landfill leachate
sodium percarbonate
chemical oxygen consumption
