地下水中三氯乙烯—苯酚的好氧共代谢的实验研究

Experimental Study on Trichloroethylene Aerobic Cometabolic Degradation with Phenol in Groundwater

以苯酚作为三氯乙烯(TCE)降解的共代谢基质,用瓦勃氏微量呼吸测压仪(简称瓦呼仪)作为测试手段,分析了经苯酚驯化后的混合微生物对苯酚、TCE的降解特性;并讨论了以苯酚作为共代谢基质时TCE降解的可能性。实验结果表明:未驯化的活性污泥不能降解TCE;经苯酚驯化后的活性污泥,当TCE的质量浓度为50μg/L时其降解效果较好,TCE的氧化率达33.69%;TCE的质量浓度为100μg/L时其降解效果较差,其氧化率仅为3.2%;苯酚和TCE共代谢降解时,苯酚的存在促进了TCE的降解,当苯酚质量浓度为40 mg/L、TCE质量浓度为50μg/L时共代谢降解效果最好,TCE的氧化率为79.11%。

The biodegradability of TCE and phenol was studied by the microorganisms acclimated with phenol, and was expressed by oxygen consumption of microorganisms measured with Warburg respirometer. The study also examined the feasibility of TCE degradation using phenol as cometabolic substrate. The results showed that TCE couldn＇t be degraded in unacclimated activated sludge. It was also demonstrated that TCE could be efficiently degraded by phenol-acclimated activated sludge at TCE concentration of 50 μg/L and the bio-oxidation ratio was 33.69% , whereas the efficiency was low at 100 μg/L with the ratio of 3.2% only. In presence of phenol and TCE, phenol enhanced TCE transformation rate. When the initial concentrations of phenol and TCE were up to 40 mg/L and 50 μg/L respectively, the maximum cometabolic degradation efficiency of TCE was obtained, up to 79. 11% in the study.