University of Hull logo

Sustained bauxite residue rehabilitation with gypsum and organic matter 16 years after initial treatment

Bray, Andrew W.; Bray, Andrew William; Stewart, Douglas I.; Courtney, Ronan; Rout, Simon; Rout, Simon P.; Humphreys, Paul N.; Mayes, William M.; Burke, Ian T.

Authors

Andrew W. Bray

Andrew William Bray

Douglas I. Stewart

Ronan Courtney

Simon Rout

Simon P. Rout

Paul N. Humphreys

Ian T. Burke



Contributors

Abstract

Bauxite residue is a high volume by-product of alumina manufacture which is commonly disposed of in purpose-built bauxite residue disposal areas (BRDAs). Natural waters interacting with bauxite residue are characteristically highly alkaline, and have elevated concentrations of Na, Al, and other trace metals. Rehabilitation of BRDAs is therefore often costly and resource/infrastructure intensive. Data is presented from three neighbouring plots of bauxite residue that was deposited twenty years ago. One plot was amended 16 years ago with process sand, organic matter, gypsum, and seeded (fully treated), another plot was amended 16 years ago with process sand, organic matter, and seeded (partially treated), and a third plot was left untreated. These surface treatments lower alkalinity and salinity, and thus produce a substrate more suitable for biological colonisation from seeding. The reduction of pH leads to much lower Al, V and As mobility in the actively treated residue and the beneficial effects of treatment extend passively 20-30 cm below the depth of the original amendment. These positive rehabilitation effects are maintained after 2 decades due to the presence of an active and resilient biological community. This treatment may provide a lower cost solution to BRDA end of use closure plans and orphaned BRDA rehabilitation.

Journal Article Type Article
Publication Date Jan 2, 2018
Journal Environmental Science & Technology
Print ISSN 0013-936X
Electronic ISSN 1520-5851
Publisher American Chemical Society
Peer Reviewed Peer Reviewed
Volume 52
Issue 1
Pages 152-161
Institution Citation Bray, A. W., Stewart, D. I., Courtney, R., Rout, S. P., Humphreys, P. N., Mayes, W. M., & Burke, I. T. (2018). Sustained bauxite residue rehabilitation with gypsum and organic matter 16 years after initial treatment. Environmental Science and Technology, 52(1), 152-161. doi:10.1021/acs.est.7b03568
DOI https://doi.org/10.1021/acs.est.7b03568
Keywords General chemistry; Environmental chemistry
Publisher URL http://pubs.acs.org/doi/10.1021/acs.est.7b03568
Copyright Statement This document is the Accepted Manuscript version of a Published Work that appeared in final form in Environmental Science & Technology, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/10.1021/acs.est.7b03568

Files

Article (801 Kb)
PDF

Copyright Statement
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Environmental Science & Technology, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/10.1021/acs.est.7b03568


Article (1.7 Mb)
PDF

Copyright Statement
ACS AuthorChoice - This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.



You might also like


Downloadable Citations