A novel sewage treatment process aimed at achieving successive methanation and low-carbon denitrogenation was configured by integrating anaerobic membrane bioreactors with nitritation-Anammox. The system performance, pollutant removal pathways, and process dynamics were investigated via analysis of pollutant transformations and microbial consortia in each reactor. The results indicated average removal efficiencies of 97.3% and 76.4%, respectively, for chemical oxygen demand and total nitrogen, corresponding to a chemical oxygen demand-to-methane conversion rate of over 83%. Organics removal was achieved mainly in the anaerobic membrane bioreactor, while denitrogenation was attained in the Anammox reactor. Hydrolysis and acidification in the anaerobic membrane bioreactor was attributable mainly to Anaerolineales, Bacteroidales, and Clostridiales. Methanothrix (58.4%) and Methanolinea (30.0%) were the primary contributors to methane production. Almost half of the NH4+-N in the AnMBR effluent was converted into NO2−-N in the nitritation reactor by Nitrosomonas. Ca. Brocadia contributed to further oxidation and removal of the residual NH4+-N using NO2−-N in the Anammox reactor. Overall, upfront methanation and subsequent low-carbon denitrogenation were achieved by integrating anaerobic membrane bioreactors with nitritation-Anammox, which provides a promising technology in the new paradigm of wastewater treatment.
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Environmental Science(all)
- Strategy and Management
- Industrial and Manufacturing Engineering