Leaching behaviour of co-disposed steel making wastes Effects of aeration on leachate chemistry and vanadium mobilisation

Leaching behaviour of co-disposed steel making wastes : Effects of aeration on leachate chemistry and vanadium mobilisation

Copyright © 2018 Elsevier Ltd. All rights reserved.

Bibliographische Detailangaben
Veröffentlicht in:Waste management (New York, N.Y.). - 1999. - 81(2018) vom: 01. Nov., Seite 1-10
1. Verfasser: Hobson, Andrew J (VerfasserIn)
Weitere Verfasser: Stewart, Douglas I, Mortimer, Robert J G, Mayes, William M, Rogerson, Mike, Burke, Ian T
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2018
Zugriff auf das übergeordnete Werk:Waste management (New York, N.Y.)
Schlagworte:Journal Article Alkaline wastes Leaching behaviour Steel slag Vanadium Industrial Waste Water Pollutants, Chemical 00J9J9XKDE Steel 12597-69-2
Beschreibung
Zusammenfassung:Copyright © 2018 Elsevier Ltd. All rights reserved.
Steelmaking wastes stored in landfill, such as slag and spent refractory liners, are often enriched in toxic trace metals (including V). These may become mobile in highly alkaline leachate generated during weathering. Fresh steelmaking waste was characterised using XRD, XRF, and SEM-EDX. Batch leaching tests were performed under aerated, air-excluded and acidified conditions to determine the impact of atmospheric CO2 and acid addition on leachate chemistry. Phases commonly associated with slag including dicalcium silicate, dicalcium aluminoferrite, a wüstite-like solid solution and free lime were identified, as well as a second group of phases including periclase, corundum and graphite which are representative of refractory liners. During air-excluded leaching, dissolution of free lime and dicalcium silicate results in a high pH, high Ca leachate in which the V concentration is low due to the constraint imposed by Ca3(VO4)2 solubility limits. Under aerated conditions, carbonation lowers the leachate pH and provides a sink for aqueous Ca, allowing higher concentrations of V to accumulate. Below pH 10, leachate is dominated by periclase dissolution and secondary phases including monohydrocalcite and dolomite are precipitated. Storage of waste under saturated conditions that exclude atmospheric CO2 would therefore provide the optimal environment to minimise V leaching during weathering
Beschreibung:Date Completed 15.07.2019
Date Revised 15.07.2019
published: Print-Electronic
Citation Status MEDLINE
ISSN:1879-2456
DOI:10.1016/j.wasman.2018.09.046