title: Phosphorus removal from municipal wastewater by hydrous ferric oxide reactive filtration and coupled chemically enhanced secondary treatment: part II--mechanism.
abstract: The removal mechanism of a hydrous ferric oxide (HFO) reactive filtration (RF) process with coupled chemically enhanced secondary treatment (RECYCLE) for phosphorus removal from municipal wastewater (HFO-RF-RECYCLE) was examined. A 0.95-ML/d (0.25-mgd) demonstration of HFO-RF-RECYCLE was performed at a municipal wastewater treatment plant equipped with oxidation ditches and secondary clarifiers. Influent to the plant averaged 6.0 mg/L phosphorus, with a 3-month tertiary effluent average of 0.011 mg/L phosphorus. In addition to aqueous geochemical modeling, experiments with surface charge, scanning electron microscopy, adsorptive capacity, thermal desorption, and most probable number of iron(III)-reducing bacteria were performed on samples from the system, to determine the major phosphorus-removal pathways. Results suggest that, in addition to filtration of particulate phosphorus, the low tertiary effluent total phosphorus result was achieved by adsorption.
authors.affiliation: University of Idaho, Moscow 83844-1052, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Newcombe
authors.forename: D G
authors.initials: DG
authors.lastname: Strawn
authors.forename: T M
authors.initials: TM
authors.lastname: Grant
authors.forename: S E
authors.initials: SE
authors.lastname: Childers
authors.forename: G
authors.initials: G
authors.lastname: Möller
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D019149:Bioreactors; D002947:Cities; D005290:Ferric Compounds / Q000737:chemistry; D005374:Filtration / Q000379:methods*; D006801:Humans; D007501:Iron / Q000737:chemistry / Q000378:metabolism; D010758:Phosphorus / Q000737:chemistry / Q000493:pharmacokinetics; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide; D010758:Phosphorus; D007501:Iron