title: Understanding the impact of influent nitrogen concentration on granule size and microbial community in a granule-based enhanced biological phosphorus removal system.
abstract: To better understand the effect of influent nitrogen concentration on granule size and microbial community in a granule-based enhanced biological phosphorus removal system, three influent nitrogen concentrations were tested while carbon concentration was an unlimited factor. The results show that although ammonium and phosphate were well removed in the tested nitrogen concentration range (20-50 mg L(-1)), granule size, the amount of phosphate accumulating organisms (PAOs) and microbial activity were affected significantly. A possible mechanism for the effect of influent nitrogen concentration on granule size is proposed based on the experimental results. The increase in proteins/polysaccharides ratio caused by high influent nitrogen concentration plays a crucial role in granule breakage. The small granule size then weakens simultaneous nitrification-denitrification, which further causes higher nitrate concentration in the effluent and lower amount of PAOs in sludge. Consequently, phosphate concentration in the anaerobic phase decreases, which plays the secondary role in granule breakage.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Jinte
authors.initials: J
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China; UNEP-Tongji Institute of Environment for Sustainable Development, Shanghai 200092, People's Republic of China. Electronic address: liyongmei@tongji.edu.cn.
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Lili
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Ruyi
authors.initials: R
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
mesh_terms: D000332:Aerobiosis / Q000187:drug effects; D000693:Anaerobiosis / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development*; D001426:Bacterial Proteins / Q000032:analysis; D001673:Biodegradation, Environmental / Q000187:drug effects; D001704:Biopolymers / Q000737:chemistry; D019149:Bioreactors / Q000382:microbiology; D058440:Denitrification; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000494:pharmacology*; D010100:Oxygen / Q000032:analysis; D010316:Particle Size; D010758:Phosphorus / Q000302:isolation & purification*; D011135:Polysaccharides, Bacterial / Q000737:chemistry; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology*; D014865:Waste Disposal, Fluid
chemical_list: D001426:Bacterial Proteins; D001704:Biopolymers; D011135:Polysaccharides, Bacterial; D012722:Sewage; D010758:Phosphorus; D009584:Nitrogen; D010100:Oxygen
keywords: Enhanced biological phosphorus removal (EBPR); Granule size; Influent nitrogen concentration; Microbial community; Proteins/polysaccharides (PN/PS) ratio