Research on pesticide treatment efficiency of constructed wetland-microbial fuel cell coupling system

Abstract:

In this study, a constructed wetland-microbial fuel cell system was constructed to treat pesticides represented by Atrazine, and to understand the pesticide treatment efficiency and treatment mechanism of the system. The results show that the system has a good treatment performance for Atrazine. When the concentration of Atrazine is less than 4 mg/L, the treatment performance of the system remains stable above 85%. Under the condition of Atrazine concentration of 4 mg/L, the system has the best power generation performance. At this time, the average daily voltage, maximum power density and current density of the system output are 284.4 mV, 19.64 mW/m3 and 46.09 mA/m3, respectively. Pesticides have a significant impact on the microbial diversity of the system, but have no significant impact on microbial gene function, and have less impact on system bacteria than the electric field. The dominant bacteria phylum of the system includes the Proteobacteria, and the dominant electrochemically active bacteria includes the Bacteroides and Firmicutes, while the dominant bacteria phylum degrading pesticides includes the Actinobacteria, the dominant bacteria classes includes Alphaproteobacteria and Actinobacteria, and the dominant bacteria genus includes Christensenellaceae_R-7_group.