Evaluating the impact of drying on leaching from a solidified/stabilized waste using a monolithic diffusion model

Copyright © 2023 Elsevier Ltd. All rights reserved.

Bibliographische Detailangaben
Veröffentlicht in:Waste management (New York, N.Y.). - 1999. - 165(2023) vom: 15. Juni, Seite 27-39
1. Verfasser: Chen, Zhiliang (VerfasserIn)
Weitere Verfasser: Zhang, Peng, Brown, Kevin G, van der Sloot, Hans A, Meeussen, Johannes C L, Garrabrants, Andrew C, Delapp, Rossane C, Um, Wooyong, Kosson, David S
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2023
Zugriff auf das übergeordnete Werk:Waste management (New York, N.Y.)
Schlagworte:Journal Article Cast Stone materials Chromium Geopolymer Mass transfer rates Physical retention property Technetium
Beschreibung
Zusammenfassung:Copyright © 2023 Elsevier Ltd. All rights reserved.
The release rates of constituents of potential concern from solidified/stabilized cementitious waste forms are potentially impacted by drying, which, however, is not well understood. This study aimed to identify the impacts of drying on subsequent leaching from Cast Stone as an example of a solidified cementitious waste form. The release fluxes of constituents from monoliths after aging under 100, 68, 40, and 15 % relative humidity for 16, 32, and 48 weeks, respectively, were derived from mass transfer tank leaching tests following EPA Method 1315. A monolithic diffusion model was calibrated based on the leaching test results to simulate the leaching of major and redox-sensitive constituents from monoliths after drying. The reduction in physical retention of constituents (tortuosity-factor) in the unsaturated zone was identified as the primary impact from drying on subsequent leaching. Fluxes of both major (i.e., OH-, Na, K, Ca, Si, and Al) and redox-sensitive constituents (i.e., Tc, Cr, Fe, and S) from monoliths during leaching were well described by the model. The drying-induced reduction of tortuosity-factor and concomitant changes in porewater pH and redox conditions can significantly change the subsequent release fluxes of pH- and redox- sensitive constituents
Beschreibung:Date Completed 25.05.2023
Date Revised 25.05.2023
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1879-2456
DOI:10.1016/j.wasman.2023.04.011