摘要:

The present study investigated the effects of lead on the morphological structure, physical and chemical properties, wastewater treatment performance and microbial community structure of aerobic granular sludge (AGS) in sequencing batch reactors (SBRs). The results showed that at Pb2+ concentration of 1mg/L, the mixed liquid suspended solids decreased, the settling velocity increased and the sludge volume index increased sharply. Meanwhile, AGS began to disintegrate and show an irregular shape. In terms of wastewater treatment in an SBR, the phosphorus removal rate was affected only until the Pb2+ concentration was up to 1mg/L. The NH4+- N removal efficiency began to decline when the Pb2+ concentration increased to 6mg/L, while the removal of chemical oxygen demand increased slightly within the Pb2+ concentration range of 1-6mg/L. Significant changes were observed in the microbial community structure, especially the dominant bacteria. Compared to the Pb2+ accumulation on the sludge, the Pb2+ concentration in the aqueous phase played a more important role in the performance and microbial community of AGS in SBRs.