The competitive relationships of PAOs-GAOs in simultaneous partial nitrification-endogenous denitrification and phosphorous removal (SPNED-PR) systems and their nutrient removal characteristics
WANG Xiao-xia1,2, WANG Shu-ying1, ZHAO Ji1, DAI Xian1, PENG Yong-zhen1
1. National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China;
2. Department of Environmental Engineering, Qingdao University, Qingdao 266071, China
In order to analyze the nitrogen (N) and phosphorus (P) removal characteristics of simultaneous partial nitrification-endogenous denitrification and phosphorus removal (SPNED-PR) systems and to elucidate the contribution and competitive relationships between phosphorus and glycogen accumulating organisms (PAOs and GAOs) in the nutrient removal, an extended anaerobic (150min)/low aerobic (180min, dissolved oxygen (DO) concentration for 0.5~0.7mg/L) operated sequencing batch reactor (SBR) fed with domestic wastewater (C/N:around 4) was studied by investigating the effects of different DO (0.5~2.0mg/L), nitrite (4.7~39.9mg/L) and nitrate (5.0~40.0mg/L) concentrations on the nutrient removal and intracellular carbons transformation. Results showed that DO had barely effects on the aerobic metabolisms of both PAOs and GAOs, and almost no PAOs-GAOs competition was detected at various DO concentrations. GAOs had a competitive advantage over PAOs at the presence of nitrite, and nitrite was mainly removed by GAOs (about 58%); GAOs had a greater tolerance to nitrite than PAOs, which alleviated the nitrite inhibition on PAOs at high nitrite concentrations (26.2~39.9mg/L) and assured the nutrient removal in the SPNED-PR system. PAOs had a competitive advantage over GAOs when nitrate was present, and it contributed to about 61.2% of total nitrate removal. Additionally, PAOs preferred to utilize DO over nitrite and nitrate for P uptake (PURDO > PURnitrate > PURnitrite), which assured the efficient P removal at low aerobic conditions. Highly active GAOs ensured the efficient N removal in the SPNED-PR system via endogenous nitrite denitrification.
王晓霞, 王淑莹, 赵骥, 戴娴, 彭永臻. SPNED-PR系统内PAOs-GAOs的竞争关系及其氮磷去除特性[J]. 中国环境科学, 2018, 38(2): 551-559.
WANG Xiao-xia, WANG Shu-ying, ZHAO Ji, DAI Xian, PENG Yong-zhen. The competitive relationships of PAOs-GAOs in simultaneous partial nitrification-endogenous denitrification and phosphorous removal (SPNED-PR) systems and their nutrient removal characteristics. CHINA ENVIRONMENTAL SCIENCECE, 2018, 38(2): 551-559.
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