中文关键词氯代烃1,2-二氯乙烷(1,2-DCA)地下水微米零价铁(mZVI)生物碳源 英文关键词chlorinated hydrocarbon1,2-dichloroethane (1,2-DCA)groundwatermicron zero valent iron (mZVI)biological carbon source

作者	单位	E-mail
吴乃瑾	轻工业环境保护研究所, 工业场地污染与修复北京市重点实验室, 北京 100089	wujin310@126.com
宋云	轻工业环境保护研究所, 工业场地污染与修复北京市重点实验室, 北京 100089	liepi_song@163.com
魏文侠	轻工业环境保护研究所, 工业场地污染与修复北京市重点实验室, 北京 100089
王海见	轻工业环境保护研究所, 工业场地污染与修复北京市重点实验室, 北京 100089
孙仲平	轻工业环境保护研究所, 工业场地污染与修复北京市重点实验室, 北京 100089

中文摘要 1，2-二氯乙烷（1，2-DCA）是一类地下水中常见的难降解饱和氯代烃，为探究厌氧条件下零价铁（ZVI）协同生物作用对其降解规律，采集北京市某氯代烃污染场地地下水及含水层土壤，利用微宇宙实验体系，通过添加由微米级零价铁（mZVI）、生物碳源及营养组成的复合药剂，考察不同条件下1，2-DCA的去除效果，并对地下水理化参数的变化进行长期监测.结果表明：复合药剂添加量为3%时，恒温、避光、匀速振荡的反应条件下，15 d内地下水中的1，2-DCA即可降至低于检出限.中性pH及SO₄^2-的存在更有利于1，2-DCA的脱氯降解.30 d后仅检测到体系中明显的乙烯产生，推测双脱氯消除为1，2-DCA在该体系内的主要降解途径.此外，复合药剂加入后，地下水可长时间维持较低的氧化还原电位（-100~-300 mV）、溶解氧（<0.5 mg·L^-1）以及适宜的pH值（6.5~7.5），利于厌氧微生物活性的维持及脱氯反应的进行. 英文摘要 In order to explore the degradation mechanism of 1,2-dichloroethane (1,2-DCA), which is one of the refractory saturated chlorinated hydrocarbons, the groundwater and aquifer soil from a chlorinated hydrocarbon contaminated site in Beijing were collected to carry out microcosm experiments under anaerobic conditions using zero-valent iron (ZVI) coupled with biological action. The removal rate of 1,2-DCA under different conditions was investigated by adding a composite agent consisting of micron zero-valent iron (mZVI), a biological carbon source, and a few nutrients. Changes of the groundwater physical and chemical parameters were monitored. The results showed that, when the dosage of the composite agent reached 3%, the concentration of 1,2-dichloroethane could be reduced to below the detection limit within 15 days. Neutral pH and the presence of SO₄^2- were more conducive to the dechlorination of 1,2-DCA. After 30 days, an obvious increase in the ethene concentration was detected (0.17-0.52 mg·L^-1) and no significant vinyl chloride, chloroethane, or ethane was observed in the microcosms, illustrating that the dihaloelimination was the main degradation pathway of 1,2-DCA in the system. In addition, the groundwater could maintain a low oxidation-reduction potential (-100 to -300 mV), dissolved oxygen (<0.5 mg·L^-1), and a suitable pH value (6.5-7.5) for a long time under the synergy of mZVI and a biological carbon source. This was beneficial to the activity of anaerobic microorganisms and to the dechlorination reaction.

PDF全文下载地址:

https://www.hjkx.ac.cn/hjkx/ch/reader/create_pdf.aspx?file_no=20190332&flag=1&journal_id=hjkx&year_id=2019