Electrolytic groundwater circulation well for trichloroethylene degradation in a simulated aquifer  

作　　者：YUAN SongHu LIU Yang ZHANG Peng TONG Man LIU Hui 

机构地区：[1]State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430074,China

出　　处：《Science China(Technological Sciences)》2021年第2期251-260,共10页中国科学（技术科学英文版）

基　　金：supported by the National Key Research&Development Program of China (Grant No. 2018YFC1802504);the Natural Science Foundation of Hubei Province (Grant No. 2018CFA028);the Fundamental Research Funds for the Central Universities,China University of Geosciences (Wuhan)(Grant No. CUGGC06)。

摘　　要：An in situ groundwater remediation process, termed EGCW, was developed in this study by integrating in-well groundwater electrolysis into groundwater circulation well. Groundwater circulation carries electrolytically generated O2 and H2 into the impacted aquifer for in situ biodegradation of contaminants. In a two-dimensional tank filled with field sandy sediments,simulated trichloroethylene(TCE)-contaminated groundwater was circulated between an injection well with electrodes inside and a pumping well. Results from a 50-day EGCW experiment show that in-well electrolysis oxygenated most region near the injection well, and 10 mg/L TCE was mainly biodegraded aerobically to about 2.7 mg/L(73% removal) by the indigenous microbes. Aerobic TCE degradation was enhanced by the pulsed addition of acetate. Together with the proofs of stable carbon isotope fractionation(enrichment factor:-0.57‰–-1.53‰) and microbial community variation after EGCW treatment, aerobic cometabolism was proposed to be the most likely mechanism for TCE degradation. It is interesting to find that the intrinsic organic carbon in aquifer matrix could fuel the aerobic TCE degradation, particularly at low TCE concentrations. EGCW treatment is advantageous in terms of supplying appropriate dosages of electron acceptor(O_(2)) and donor(H_(2)) for in situ bioremediation because groundwater electrolysis and circulation are expedient and controllable.

关 键 词：electrolytic remediation groundwater circulation wells chlorinated solvents BIODEGRADATION 

分 类 号：X523[环境科学与工程—环境工程]