title: Extraction of raw sewage sludge containing iron phosphate for phosphorus recovery.
abstract: The objective of the present study was to establish an alkali extraction technology for FePO(4)-containing sewage sludge obtained from a wastewater treatment system that includes phosphorous removal by iron electrolysis. By clarifying the extraction properties of phosphorous, organic matter, and inorganic matter, conditions for alkali extraction were optimized. As a result, it was suggested that unheated phosphorous extraction would be superior for FePO(4)-containing sewage sludge. And, extraction methods and sewage sludge properties were also compared, and the noteworthy result that extraction of metals can be suppressed to extremely low amounts with alkali extraction as compared with acid extraction was obtained. A new insight was also gained that, as compared with the use of incinerated ash reported in previous studies, alkali extraction was more efficient when raw sewage sludge was used.
authors.affiliation: Environmental Restoration and Conservation Technology Section, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan. sano.akira@nies.go.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Sano
authors.forename: Makoto
authors.initials: M
authors.lastname: Kanomata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Inoue
authors.forename: Norio
authors.initials: N
authors.lastname: Sugiura
authors.forename: Kai-Qin
authors.initials: KQ
authors.lastname: Xu
authors.forename: Yuhei
authors.initials: Y
authors.lastname: Inamori
mesh_terms: D003247:Conservation of Natural Resources / Q000379:methods; D005290:Ferric Compounds / Q000032:analysis* / Q000737:chemistry; D010758:Phosphorus / Q000032:analysis* / Q000737:chemistry; D012722:Sewage / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D010758:Phosphorus; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical; C035885:ferric phosphate