title: Direct phosphorus recovery from municipal wastewater via osmotic membrane bioreactor (OMBR) for wastewater treatment.
abstract: This work reports, for the first time, a new approach to direct phosphorus recovery from municipal wastewater via an osmotic membrane bioreactor (OMBR). In the OMBR, organic matter and NH4(+) were removed by biological activities. PO4(3)(-), Ca(2+), Mg(2+) and unconverted NH4(+) were rejected by the forward osmosis (FO) membrane and enriched within the bioreactor. The resultant phosphorus-rich supernatant was then used for phosphorus recovery. By adjusting the pH to 8.0-9.5, PO4(3)(-) was recovered via precipitation with Ca(2+), Mg(2+) and NH4(+). The OMBR showed up to 98% overall removal of TOC and NH4(+)-N. At pH 9.0, more than 95% PO4(3)(-)-P was recovered without addition of magnesium and calcium. The precipitates were predominantly amorphous calcium phosphate (ACP) with phosphorus content >11.0%. In principal, this process can recover almost all the phosphorus, apart from the portion assimilated by bacteria. The global phosphorus recovery efficiency was shown to be 50% over 84 days.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
authors.forename: Guanglei
authors.initials: G
authors.lastname: Qiu
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore. Electronic address: chetyp@nus.edu.sg.
authors.forename: Yen-Peng
authors.initials: YP
authors.lastname: Ting
mesh_terms: D019149:Bioreactors; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D009997:Osmotic Pressure; D010758:Phosphorus / Q000302:isolation & purification*; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D010758:Phosphorus; D062065:Wastewater
keywords: Amorphous calcium phosphate (ACP); Municipal wastewater; Osmotic membrane bioreactor (OMBR); Phosphorus recovery; Struvite