title: Biological phosphorus and nitrogen removal in sequencing batch reactors: effects of cycle length, dissolved oxygen concentration and influent particulate matter.
abstract: Removal of phosphorus (P) and nitrogen (N) from municipal wastewaters is required to mitigate eutrophication of receiving water bodies. While most treatment plants achieve good N removal using influent carbon (C), the use of influent C to facilitate enhanced biological phosphorus removal (EBPR) is poorly explored. A number of operational parameters can facilitate optimum use of influent C and this study investigated the effects of cycle length, dissolved oxygen (DO) concentration during aerobic period and influent solids on biological P and N removal in sequencing batch reactors (SRBs) using municipal wastewaters. Increasing cycle length from 3 to 6 h increased P removal efficiency, which was attributed to larger portion of N being removed via nitrite pathway and more biodegradable organic C becoming available for EBPR. Further increasing cycle length from 6 to 8 h decreased P removal efficiencies as the demand for biodegradable organic C for denitrification increased as a result of complete nitrification. Decreasing DO concentration in the aerobic period from 2 to 0.8 mg L(-1) increased P removal efficiency but decreased nitrification rates possibly due to oxygen limitation. Further, sedimented wastewater was proved to be a better influent stream than non-sedimented wastewater possibility due to the detrimental effect of particulate matter on biological nutrient removal.
authors.affiliation: CSIRO Land and Water, Floreat, WA 6014, Australia E-mail: maneesha.ginige@csiro.au.
authors.forename: Maneesha P
authors.initials: MP
authors.lastname: Ginige
authors.forename: Ahmet S
authors.initials: AS
authors.lastname: Kayaalp
authors.forename: Ka Yu
authors.initials: KY
authors.lastname: Cheng
authors.forename: Jason
authors.initials: J
authors.lastname: Wylie
authors.forename: Anna H
authors.initials: AH
authors.lastname: Kaksonen
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D009584:Nitrogen / Q000302:isolation & purification / Q000378:metabolism*; D010100:Oxygen / Q000737:chemistry; D052638:Particulate Matter / Q000737:chemistry; D010758:Phosphorus / Q000302:isolation & purification / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D052638:Particulate Matter; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen; D010100:Oxygen