title: The Relevance of Phosphorus and Iron Chemistry to the Recovery of Phosphorus from Wastewater: A Review.
abstract: The addition of iron is a convenient way for removing phosphorus from wastewater, but this is often considered to limit phosphorus recovery. Struvite precipitation is currently used to recover phosphorus, and this approach has attracted much interest. However, it requires the use of enhanced biological phosphorus removal (EBPR). EBPR is not yet widely applied and the recovery potential is low. Other phosphorus recovery methods, including sludge application to agricultural land or recovering phosphorus from sludge ash, also have limitations. Energy-producing wastewater treatment plants increasingly rely on phosphorus removal using iron, but the problem (as in current processes) is the subsequent recovery of phosphorus from the iron. In contrast, phosphorus is efficiently mobilized from iron by natural processes in sediments and soils. Iron-phosphorus chemistry is diverse, and many parameters influence the binding and release of phosphorus, including redox conditions, pH, presence of organic substances, and particle morphology. We suggest that the current poor understanding of iron and phosphorus chemistry in wastewater systems is preventing processes being developed to recover phosphorus from iron-phosphorus rich wastes like municipal wastewater sludge. Parameters that affect phosphorus recovery are reviewed here, and methods are suggested for manipulating iron-phosphorus chemistry in wastewater treatment processes to allow phosphorus to be recovered.
authors.affiliation: †Wetsus, European Centre Of Excellence for Sustainable Water Technology, Oostergoweg 7, 8911 MA Leeuwarden, The Netherlands.|‡Dept. Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Philipp
authors.initials: P
authors.lastname: Wilfert
authors.affiliation: †Wetsus, European Centre Of Excellence for Sustainable Water Technology, Oostergoweg 7, 8911 MA Leeuwarden, The Netherlands.|‡Dept. Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Prashanth Suresh
authors.initials: PS
authors.lastname: Kumar
authors.affiliation: †Wetsus, European Centre Of Excellence for Sustainable Water Technology, Oostergoweg 7, 8911 MA Leeuwarden, The Netherlands.
authors.forename: Leon
authors.initials: L
authors.lastname: Korving
authors.affiliation: †Wetsus, European Centre Of Excellence for Sustainable Water Technology, Oostergoweg 7, 8911 MA Leeuwarden, The Netherlands.|‡Dept. Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Geert-Jan
authors.initials: GJ
authors.lastname: Witkamp
authors.affiliation: ‡Dept. Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
authors.forename: Mark C M
authors.initials: MC
authors.lastname: van Loosdrecht
mesh_terms: D006812:Humic Substances; D007501:Iron / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry* / Q000302:isolation & purification*; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification
chemical_list: D006812:Humic Substances; D007501:Iron; D010758:Phosphorus; D062065:Wastewater