Projekter pr. år
Abstract
Phosphorus recycling from secondary materials like sewage sludge ashes offers an interesting alternative to imported mineral phosphates. However, a separation of P from the bulk ash is normally required, due to its low plant availability and the presence of heavy metals. More than 80% of P was recovered from incineration sewage sludge ashes in the past using a two-compartment electrodialytic cell. In contrast, the recovery was below 30% for ashes from low-temperature gasification using the same setup, due to the high presence of Al- and Fe(III)-P bindings. In the present study, an electrodialytic process combining sequentially a pair of two-compartment cells allowed a recovery of up to 70% of phosphorus from these ashes. The use of a second cell, where the ashes were treated in an alkaline pH, allowed the P solubilisation from aluminium and ferric phosphates and its separation from most metals as they became insoluble. Furthermore, the ratio of Al, Fe, Mg and most heavy metals to P was comparable to wet process phosphoric acid. Therefore, this sequential process was found to be suitable to recycle P and potentially use it in the production of common fertilizers like diammonium phosphate.
Bidragets oversatte titel | Sequential electrodialytic recovery of phosphorus from low-temperature gasification ashes of chemically precipitated sewage sludge |
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Originalsprog | Engelsk |
Tidsskrift | Waste Management |
Vol/bind | 60 |
Sider (fra-til) | 211-218 |
Antal sider | 7 |
ISSN | 0956-053X |
DOI | |
Status | Udgivet - 2017 |
Projekter
- 1 Afsluttet
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Fuel-Flexible, Efficient and Sustainable Low Temperature Gasification
Hauggaard-Nielsen, H. (Projektdeltager)
01/04/2012 → 01/09/2016
Projekter: Projekt › Forskning