title: Simultaneous phosphorus uptake and denitrification by EBPR-r biofilm under aerobic conditions: effect of dissolved oxygen.
abstract: A biofilm process, termed enhanced biological phosphorus removal and recovery (EBPR-r), was recently developed as a post-denitrification approach to facilitate phosphorus (P) recovery from wastewater. Although simultaneous P uptake and denitrification was achieved despite substantial intrusion of dissolved oxygen (DO >6 mg/L), to what extent DO affects the process was unclear. Hence, in this study a series of batch experiments was conducted to assess the activity of the biofilm under various DO concentrations. The biofilm was first allowed to store acetate (as internal storage) under anaerobic conditions, and was then subjected to various conditions for P uptake (DO: 0-8 mg/L; nitrate: 10 mg-N/L; phosphate: 8 mg-P/L). The results suggest that even at a saturating DO concentration (8 mg/L), the biofilm could take up P and denitrify efficiently (0.70 mmol e(-)/g total solids*h). However, such aerobic denitrification activity was reduced when the biofilm structure was physically disturbed, suggesting that this phenomenon was a consequence of the presence of oxygen gradient across the biofilm. We conclude that when a biofilm system is used, EBPR-r can be effectively operated as a post-denitrification process, even when oxygen intrusion occurs.
authors.affiliation: CSIRO, Land and Water Flagship, Floreat, Western Australia 6014, Australia E-mail: kayu.cheng@csiro.au; School of Pathology and Laboratory Medicine, University of Western Australia, Nedlands, Western Australia 6009, Australia.
authors.forename: Pan Yu
authors.initials: PY
authors.lastname: Wong
authors.affiliation: CSIRO, Land and Water Flagship, Floreat, Western Australia 6014, Australia E-mail: kayu.cheng@csiro.au.
authors.forename: Maneesha P
authors.initials: MP
authors.lastname: Ginige
authors.affiliation: CSIRO, Land and Water Flagship, Floreat, Western Australia 6014, Australia E-mail: kayu.cheng@csiro.au; School of Pathology and Laboratory Medicine, University of Western Australia, Nedlands, Western Australia 6009, Australia.
authors.forename: Anna H
authors.initials: AH
authors.lastname: Kaksonen
authors.affiliation: School of Engineering and Information Technology, Murdoch University, Perth, Western Australia 6150, Australia.
authors.forename: Ralf
authors.initials: R
authors.lastname: Cord-Ruwisch
authors.affiliation: School of Pathology and Laboratory Medicine, University of Western Australia, Nedlands, Western Australia 6009, Australia.
authors.forename: David C
authors.initials: DC
authors.lastname: Sutton
authors.affiliation: CSIRO, Land and Water Flagship, Floreat, Western Australia 6014, Australia E-mail: kayu.cheng@csiro.au; School of Engineering and Information Technology, Murdoch University, Perth, Western Australia 6150, Australia.
authors.forename: Ka Yu
authors.initials: KY
authors.lastname: Cheng
mesh_terms: D000332:Aerobiosis; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology; D058440:Denitrification; D008962:Models, Theoretical; D009566:Nitrates / Q000032:analysis* / Q000302:isolation & purification; D010100:Oxygen / Q000737:chemistry*; D010758:Phosphorus / Q000032:analysis* / Q000302:isolation & purification; D062065:Wastewater / Q000737:chemistry; D018508:Water Purification / Q000379:methods*
chemical_list: D009566:Nitrates; D010100:Oxygen; D010758:Phosphorus; D062065:Wastewater