Highly-efficient nitrogen removal from domestic wastewater based on enriched aerobic/anoxic biological filters and functional microbial Community characteristics

摘要

An enriched aerobic/anoxic biological filter (EABF) filled with iron-based microbial coupling carrier (IBMC) was used for highly efficient biodegradation of nitrogen pollutants in low C/N ratio domestic wastewater. The nitrogen removal efficiency, functional microbiological community of nitrogen cycle, and iron cycle in the EABF based on IBMC, were investigated. The NH4+-N, TN and COD removal efficiency were 97.6%, 86.9% and 85.3%, respectively, in the EABF-filled IBMC with DO of 3.5 mg L-1, HRT of 12 h and reflux ratio of 5.5:1. Furthermore, differences were observed in the microbial communities, and Thiobacillus, Denitratisoma and Saprospiraceae were the dominant genera. Nitrosomonadaceae, Nitrospira, Ferritrophicum and Acidovorax were dominant in the nitrogen and iron-cycle communities. Besides, IBMC significantly affected the microbial compositions. Thus, the developed EABF achieved efficient nutrients removal from low C/N ratio domestic sewage, which is suitable for practical application. (C) 2019 Elsevier Ltd. All rights reserved.