MOK Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, PR China; Industrial Technology Office, Ministry of Environmental Protection Center for Foreign Cooperation, Beijing, 100035, PR China.
School of Civil Engineering, Tangshan University, Tangshan, 063000, PR China.
Chemosphere. 2022 Dec;308(Pt 1):136262. doi: 10.1016/j.chemosphere.2022.136262. Epub 2022 Aug 30.
In this research, a comprehensive study was carried out on the removal of carbon tetrachloride (CT) in the anaerobic co-metabolism (ACM) reactor. The experiments showed that when the hydraulic retention time (HRT) was 36 h, pH was 7, and influent CT was 2.5mg/L, the average removal efficiency reached 82.45 ± 2.56% in the glucose co-metabolism substrate reactor, exhibiting a dramatic excellent difference in reaction performance from the other two reactors (p < 0.05) and a favorable tolerance on the CT shock loading. The content of extracellular polymeric substances (EPS) and volatile fatty acids (VFA) demonstrated that glucose could supply more energy to protect the microorganisms, which was the appropriate external energy source. Moreover, microbial community structure and biostatistics analysis demonstrated that Pseudomonas was the most important dechlorination bacteria in ACM reactors, which might via dehalogenation process mediate the transformation of CT. The succession of methanogenic bacteria further demonstrated that CT degradation using co-digestion require to destroy hydrogenotrophic methane generation pathway and the external energy substances could make up the lack of hydrogen in the treatment of CT. The change of intermediate products hinted that anaerobic dechlorination process of CT in an ACM reactor was a sequential dechlorination process, and major transformation products measured were CF. Overall, this study has improved our understanding of the roles of CT degradation process in ACM reactors.
在这项研究中，我们对四氯化碳（CT）在厌氧共代谢（ACM）反应器中的去除进行了全面研究。实验表明，当水力停留时间（HRT）为 36 小时、pH 值为 7、进水 CT 为 2.5mg/L 时，葡萄糖共代谢基质反应器中的平均去除效率达到 82.45±2.56%，与其他两个反应器相比，反应性能有显著的差异（p<0.05），并且对 CT 冲击负荷有良好的耐受性。胞外聚合物物质（EPS）和挥发性脂肪酸（VFA）的含量表明，葡萄糖可以提供更多的能量来保护微生物，这是合适的外部能源。此外，微生物群落结构和生物统计学分析表明，假单胞菌是 ACM 反应器中最重要的脱氯菌，它可能通过脱卤化作用介导 CT 的转化。产甲烷菌的演替进一步表明，共消化处理 CT 需要破坏产氢甲烷生成途径，并且外部能源物质可以弥补处理 CT 中氢的缺乏。中间产物的变化表明，ACM 反应器中 CT 的厌氧脱氯过程是一个顺序脱氯过程，测量到的主要转化产物是 CF。总的来说，本研究提高了我们对 CT 降解过程在 ACM 反应器中的作用的认识。
