Effects of side-stream ratio on sludge reduction and microbial structures of anaerobic side-stream reactor coupled membrane bioreactors.
An anoxic/oxic membrane bioreactor (AO-MBR) and three anaerobic side-stream reactor (ASSR) coupled MBRs (ASSR-MBR) were operated to investigate effects of side-stream ratio (SR) on sludge reduction and microbial community structure of ASSR-MBRs. The ASSR-MBR achieved efficient COD and ammonium nitrogen removal. SR increased from 0.2 to 1.0 favored nitrogen removal, and increased sludge reduction from 6.0% to 49.7%. The total released COD in the ASSR increased with the rising SR and was inversely proportional to sludge yield of ASSR-MBR. Pyrosequencing analysis showed that phyla Chloroflexi and Armatimonadetes surviving in anaerobic conditions were enriched in the ASSR, while Nitrospirae was dominant in the MBR. Comparison at the genus level revealed that higher SR favored the growth of slow growers, while lower SR enriched hydrolytic and predatory bacteria. The results suggested that SR has a profound effect on nitrogen removal, sludge reduction and microbial community structure in the ASSR-MBR.
College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Cheng
C
Cheng
College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China. Electronic address: zhouzhen@shiep.edu.cn.
Zhen
Z
Zhou
College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Tianhao
T
Niu
College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Ying
Y
An
College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Xuelian
X
Shen
Shanghai Municipal Sewerage Co., Ltd, Shanghai 200233, China.
Wei
W
Pan
Shanghai Municipal Sewerage Co., Ltd, Shanghai 200233, China.
Zhihui
Z
Chen
College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China.
Jin
J
Liu
D064751:Ammonium Compounds / Q000302:isolation & purification; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D041862:Chloroflexi / Q000254:growth & development; D006868:Hydrolysis; D010084:Oxidation-Reduction; D012722:Sewage / Q000032:analysis* / Q000382:microbiology
D064751:Ammonium Compounds; D012722:Sewage
Anaerobic side-stream reactor; Membrane bioreactor; Microbial community; Sludge reduction; Wastewater treatment