Reproducibility of Aerobic Granules in Treating Low-Strength and Low-C/N-Ratio Wastewater and Associated Microbial Community Structure

Long-term stability of the aerobic granular sludge system is essentially based on microbial community structure biomass. In this study, physicochemical and characteristics wastewater treatment performance were investigated regarding formation, maturation, long-term maintenance granules in two parallel sequencing batch reactors (SBR), R1 R2, under identical conditions. The aim was to explore linkage between granules, their stability, as well reproducibility granulation stability. operated with a COD concentration 400 mg/L chemical oxygen demand nitrogen (COD/N) ratio 4:1 anoxic–oxic It found that although SVI30, size, distributions R2 different, formed, they maintained both for 320 days, implying certain level randomness does not affect N removal. addition, significant reduction richness diversity production observed after converted from inoculum or flocs but did negatively treatment. Among predominant species Zoogloea identified most important bacteria present during whole operation highest abundance, while Thauera genus formation maturation it cannot be due low food-to-microorganisms (F/M) system. some Ohtaekwangia, Chryseobacterium, Taibaiella, Tahibacter proliferate strongly granules. They may play an role These results demonstrate granulation, small influence robustness removal N. Overall, our study contributes significantly understanding low-COD low-COD/N-ratio practice.