Electricity production and evolution of microbial community in the constructed wetland-microbial fuel cell
Fei Xu, Fu-qian Cao, Qiang Kong, Lu-luZhou, Qing Yuan, Ya-jieZhu, Qian Wang, Yuan-da Du, Zhi-de Wang
College of Geography and Environment, Collaborative Innovation Center of Human-Nature and Green Development in Universities of Shandong, Shandong Normal University, Jinan 250014, PR China.
Constructed wetlands combined with microbial fuel cell (CW-MFC) could purify the wastewater while using microorganisms to generate electricity. Our study investigated pollutant removal and microorganism evolution in CW and CW-MFC. The average removal rate of total nitrogen (82.46 ± 4.74%) in the CW-MFC was highly significant (p < 0.01) higher than that in the CW. The average removal rate of chemical oxygen demand (82.32 ± 12.85%) and total phosphorus (95.06 ± 5.45%) in the CW-MFC were higher than those in the CW. In the CW-MFC, the average voltage was 265.77 ± 12.66 mV and the highest power density was 3714.08 mW·m−2. The microbial community diversity and richness of the CW-MFC system were higher than those of the CW system. The read number of ammonia oxidizing (149 ± 7), nitrite-oxidizing (144 ± 8, 132 ± 18) and anammox bacteria (281 ± 8) were the highest in the CW-MFC (Anode). The contents of denitrification, dissimilatory nitrate reduction to ammonium, and electrochemically active bacteria in the CW-MFC (Cathode) were significantly (p < 0.05) higher than others.
Keywords: Constructed wetland, Electricity production performance, Microbial diversity, Microbial fuel cell, Wastewater treatment.