Decomposition of pollutants from domestic sewage with the combination systems of hydrolytic acidification coupling with constructed wetland microbial fuel cell

Abstract

In this research, three highly efficient combination systems, including constructed wetland microbial fuel cell (CWMFC), hydrolytic sludge acidification coupling with constructed wetland microbial fuel cell (HSA-CWMFC) and hydrolytic filler acidification coupling with constructed wetland microbial fuel cell (HFA-CWMFC), were applied to the removal of pollutants from domestic sewage. The three combination systems could effectively treat domestic sewage and generate clean energy. The power generated by CWMFC, HSA-CWMFC, and HFA-CWMFC was 0.36 W/m2, 0.40 W/m2, and 0.43 W/m2, respectively. The results indicated that the removal rates of chemical oxygen demand (COD), total organic carbon (TOC), total phosphorus (TP), ammonia nitrogen (NH3–N), and nitrate nitrogen (NO3−-N) in HFA-CWMFC could achieve the optimal values of 91.01%, 90.63%, 95.35%, 86.11%, and 91.01%, respectively. In addition, HFA-CWMFC produced more organic acids than HSA-CWMFC, which was beneficial to the follow-up reaction. Through qualcomm sequencing analysis, it could be seen that Firmicutes, which could enhance power generation capacity and increase removal rates of pollutants, played an important role in HFA-CWMFC. The results demonstrated that the three combined systems had excellent application prospects for sewage treatment and energy generation.