Kinetics and capacity of phosphorus extraction from solid residues obtained from wet air oxidation of sewage sludge
Copyright © 2019 Elsevier Ltd. All rights reserved.
| Publié dans: | Waste management (New York, N.Y.). - 1999. - 89(2019) vom: 15. Apr., Seite 275-283 |
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| Auteur principal: | |
| Autres auteurs: | , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2019
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| Accès à la collection: | Waste management (New York, N.Y.) |
| Sujets: | Journal Article Acidic leaching Kinetic model Phosphorus recovery Sewage sludge Wet air oxidation residue Fertilizers Sewage Phosphorus 27YLU75U4W |
| Résumé: | Copyright © 2019 Elsevier Ltd. All rights reserved. Solid residues from thermal treatments of sewage sludge (SS) represent a valuable source of phosphorus (P) for the fertilizer production. This study aims at evaluating the P recovery potential from solid residues obtained from wet air oxidation of SS under subcritical water conditions (WAO residues). A series of P extraction experiments was performed by acidic and alkaline leaching at different liquid to solid ratios. Hot chemical extractions and P fractionations were also carried out to characterize the chemical composition of the WAO residues. The main objectives of this work were to determine the best operating conditions for P extraction, and to describe and understand the kinetics and the main mechanisms leading to P release. The results obtained in this study indicate that 1 M citric acid and 1 M HCl at the liquid to solid ratio of 10 L/kg can extract 61% and 65% of the total P content after 2 h of contact time at room temperature, thus giving P extraction capacities of 81 and 86 g P/kg WAO residues, respectively. The analysis of kinetic data indicates that P extraction with 1 M HCl is faster, but 1 M citric acid can give higher P extraction efficiencies at the equilibrium. The molar ratios of Ca to P of the leachates suggest that P extraction from WAO residues was primarily due to the dissolution of a mixture of various Ca-P complexes |
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| Description: | Date Completed 12.09.2019 Date Revised 12.09.2019 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1879-2456 |
| DOI: | 10.1016/j.wasman.2019.04.024 |