Abstract:Due to the maturity of technology, the activated sludge process has been applied in the treatment of high ammonia nitrogen wastewater. With continuous development, many new activated sludge-based processes have also become research hotspots. Partial nitrification (PN) has gradually emerged as a representative. Partial nitrification can achieve the purpose of purifying sewage efficiently; and the hydroxylamine, one of the metabolites in the reaction, also has a vital influence on the microbial community and the reaction products. The microbial community structure and dynamics of activated sludge in PN reactors are closely related with nitrifying process. Exploring the microbial community structure can help bio-enhancement, optimizing parameters and improve nitrogen removal efficiency. This review mainly summarized the recent advances on microbial community composition and structure of the activated sludge for partial nitrification/half partial nitrification and their relationships with reactor performances, as well as the effect of hydroxylamine metabolism on partial nitrification. These results have reinforced our understanding of microbial community structure and wastewater treatment processes, but the path to fully exploiting biological information and improving process efficiency remains challenging. It is also necessary to use a variety of biotechnology methods to conduct comprehensive research on partial nitrification and provide a solid theoretical basis for practice.
