Highly-efficient nitrogen removal from domestic wastewater based on enriched aerobic/anoxic biological filters and functional microbial community characteristics. (20th November 2019) - Hu, Zhifeng
Abstract: 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. Highlights: A biological filters achieved efficient nutrients removal from domestic sewage. Dissolved oxygen, hydraulic retention time and reflux ratio influence the process. Aerobic and anoxic microbial communities reflecting different composition. Functional microbial community of nitrogen and iron cycle were investigated.