title: A novel post denitrification configuration for phosphorus recovery using polyphosphate accumulating organisms.
abstract: Enhanced biological phosphorus removal (EBPR) has been widely used to remove phosphorus (P) from wastewater. In this study we report a novel modification to the EBPR approach, namely enhanced biological phosphorus removal and recovery (EBPR-r) that facilitates biological recovery of P from wastewater using a post denitrification configuration. The novel approach consists of two major steps. In the first step, a biofilm of phosphorus accumulating organisms (PAOs) is exposed to a wastewater stream in the absence of active aeration, during which P is taken up by the biofilm using nitrate and residual dissolved oxygen as electron acceptors. Thus, P and nitrogen (N) removal from wastewater is achieved. During the second step, the P enriched biofilm is exposed to a smaller recovery stream supplemented with an external carbon source to facilitate P release under anaerobic conditions. This allows P to be recovered as a concentrated liquid. The EBPR-r process was able to generate a P recovery stream four time more concentrated (28 mg-P/L) than the wastewater stream (7 mg-P/L), while removing nitrate (denitrification) from the wastewater stream. Repeated exposure of the biofilm (10 P-uptake and release cycles) to a recovery stream yielded up to 100 mg-P/L. Overall, EBPR-r is the first post denitrification strategy that can also facilitate P recovery during secondary wastewater treatment.
authors.affiliation: CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; School of Pathology and Laboratory Medicine, University of Western Australia, Nedlands, WA 6009, Australia.
authors.forename: Pan Yu
authors.initials: PY
authors.lastname: Wong
authors.forename: Ka Yu
authors.initials: KY
authors.lastname: Cheng
authors.forename: Anna H
authors.initials: AH
authors.lastname: Kaksonen
authors.forename: David C
authors.initials: DC
authors.lastname: Sutton
authors.forename: Maneesha P
authors.initials: MP
authors.lastname: Ginige
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology; D003365:Costs and Cost Analysis; D058440:Denitrification; D004583:Electrons; D007700:Kinetics; D009584:Nitrogen / Q000302:isolation & purification; D010758:Phosphorus / Q000302:isolation & purification*; D011122:Polyphosphates / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology; D012995:Solubility
chemical_list: D011122:Polyphosphates; D012722:Sewage; D010758:Phosphorus; D009584:Nitrogen
keywords: Denitrifying polyphosphate accumulating organisms; Enhanced biological phosphorus removal; Phosphorus recovery; Phosphorus removal; Polyphosphate accumulating organisms; Post denitrification; Wastewater treatment