地下水高浓度三氯乙烯厌氧生物降解的进展

Review of Anaerobic Dechlorination of High Concentrated Trichloroethylene in Groundwater

三氯乙烯是工业中普遍使用的有机溶剂,是土壤和地下水中普遍存在的污染物,而高浓度三氯乙烯污染更具有持久性。本文从高浓度三氯乙烯脱氯降解的可行性入手,分析其厌氧还原脱氯的降解途径和降解机制的重要要素:电子供体和微生物。同时,讨论了pH值及各种抑制因素对脱氯程度和速率的影响,着重综合比较了常用的还原降解动力学模型,并对今后的研究发展趋势进行了展望。在试验方面,耐高浓度氯代乙烯的脱氯菌株的筛选和培养,以及电子供体基质的效果需要进一步研究;在数值模拟方面,生物反应、水文地球化学反应和地下水物理流动、多组分溶质运移相耦合的模型仍较缺乏,此外模型中的诸多反应类参数仍缺少系统的实验验证,这些都需要进一步研究。

Trichloroethylene （TCE） is an organic solvent widely used in industry and commonly exists in soil and groundwater, while high concentrated TCE may lead to persistent pollution. Based on the feasibility of the degradation of high concentrated TCE, the pathway of anaerobic reductive dechlorination and the main factors influencing degradation, i.e., electron donor and microorganism, were reviewed in this paper. Meanwhile, we discussed the impact of pH and various restricting factors on the degree and the rate of reduetive dechlorination. Commonly used kinetic models for the reductive degradation kinetics were listed and compared. The trend of future research was discussed. In experiment, selecting and cultivating of deehlorination bacterium which can survive in source zones with high concentrated chlorinated ethene and the effect of electron donor substrates need further study. In numerical simulation, models are required for comprehensive simulation of biological reaction, hydrogeochemical reaction, as well as physical flow and multi-species transport in groundwater. Moreover, parameters in these models lack verification, which need further study.