title: Effect of sludge retention time on continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.
abstract: The effect of sludge retention time (SRT) on the continuous-flow system with enhanced biological phosphorus removal (EBPR) granules at different COD loading was investigated during the operation of more than 220days. And the results showed that when the system operated at long SRT (30days) and low COD loading (200mg·L(-1)), it could maintain excellent performance. However, long SRT and high COD loading (300mg·L(-1)) deteriorated the settling ability of granules and the performance of system and resulted in the overgrowth of filamentous bacteria. Meanwhile, the transformation of poly-β-hydroxyalkanoates (PHAs) and glycogen in metabolism process was inhibited. Moreover, the results of pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading and long SRT. The PAOs specious of Candidatus_Accumlibater and system performance increased obviously when the SRT was reduced to 20days at high COD loading.
authors.affiliation: Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China. Electronic address: lidong2006bjuteducn@163.com.
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.affiliation: Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Lv
authors.affiliation: Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China.
authors.forename: Huiping
authors.initials: H
authors.lastname: Zeng
authors.affiliation: Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100123, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006003:Glycogen / Q000378:metabolism; D059014:High-Throughput Nucleotide Sequencing; D010758:Phosphorus / Q000302:isolation & purification*; D054813:Polyhydroxyalkanoates / Q000378:metabolism; D011122:Polyphosphates / Q000378:metabolism; D012722:Sewage / Q000382:microbiology*; D013997:Time Factors
chemical_list: D054813:Polyhydroxyalkanoates; D011122:Polyphosphates; D012722:Sewage; D010758:Phosphorus; D006003:Glycogen
keywords: COD loading; Continuous-flow system; EBPR granules; High-throughput pyrosequencing; Sludge retention