Extraction efficiency of phosphate from pre-coagulated sludge with NaHS

The recovery of phosphorus from sewage and sludge treatment systems is particularly important because it is a limited resource and a large proportion of the phosphorus currently used in Japan must be imported. We have been experimentally evaluating recovery methods with sulphide. In this study, we f...

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Bibliographische Detailangaben
Veröffentlicht in:Water science and technology : a journal of the International Association on Water Pollution Research. - 1986. - 54(2006), 5 vom: 23., Seite 119-29
1. Verfasser: Kato, F (VerfasserIn)
Weitere Verfasser: Kitakoji, H, Oshita, K, Takaoka, M, Takeda, N, Matsumoto, T
Format: Aufsatz
Sprache:English
Veröffentlicht: 2006
Zugriff auf das übergeordnete Werk:Water science and technology : a journal of the International Association on Water Pollution Research
Schlagworte:Journal Article Chlorides Ferric Compounds Phosphates Sewage Sulfides Iron E1UOL152H7 sodium bisulfide FWU2KQ177W mehr... ferric phosphate N6BAA189V1 ferric chloride U38V3ZVV3V
Beschreibung
Zusammenfassung:The recovery of phosphorus from sewage and sludge treatment systems is particularly important because it is a limited resource and a large proportion of the phosphorus currently used in Japan must be imported. We have been experimentally evaluating recovery methods with sulphide. In this study, we focussed on the extraction of phosphate from the sludge, and sought to achieve a greater extraction efficiency and to validate the extraction mechanism. We conducted three experiments, i.e. a sludge-type experiment, a coagulant ratio of pre-coagulated sludge experiment, and a concentration of pre-coagulated sludge experiment. Phosphate was extracted not with normal sewage sludge but with pre-coagulated sludge and FePO4 reagent at S/Fe = 1.0-2.0. A coagulant ratio of 23mg Fe L(-1) was required in the precoagulation process to effectively extract phosphate. A high concentration of pre-coagulated sludge was required for the phosphate extraction. The mass balance was calculated, and 44.0% of phosphorus was extracted to supernatant, and 98.5% of iron and 98.3% of sulphur (44.1% of sulphur was sulphide). Thus, phosphate can be selectively separated from iron by the phosphate extraction method with NaHS, and phosphorus and iron can be recovered and reused at sewage treatment plants using ferric chloride as a coagulant
Beschreibung:Date Completed 01.02.2007
Date Revised 17.09.2019
published: Print
Citation Status MEDLINE
ISSN:0273-1223