Remediation of contaminated soil by red mud and paper ash

JOURNAL OF CLEANER PRODUCTION

卷:256

Article

Oprckal, P.¹  Mladenovic, A.¹  Zupancic, N.²  Scancar, J.^3,4  Milacic, R.^3,4  Serjun, V. Zalar¹ 

[1] Slovenian Natl Bldg & Civil Engn Inst, Dimiceva 12, Ljubljana 1000, Slovenia

[2] Univ Ljubljana, Fac Nat Sci & Engn, Dept Geol, Askerceva 12, Ljubljana 1000, Slovenia

[3] Jozef Stefan Inst, Dept Environm Sci, Jamova 39, Ljubljana 1000, Slovenia

[4] Jozef Stefan Int Postgrad Sch, Jamova 39, Ljubljana 1000, Slovenia

关键词: Red mud;    Paper ash;    Contaminated soil;    Potentially toxic elements;    Geotechnical composites;   

DOI  :  10.1016/j.jclepro.2020.120440

来源: Elsevier

【 摘 要 】

Remediation of contaminated soil can be performed by using various techniques, which must be adequately tailored for each specific case. The aim of this research is to critically evaluate the potential use of red mud and paper ash and a combination of the two as immobilization additives for the remediation of contaminated soil from one of the most polluted sites in Slovenia. The proposed procedure involves the preparation of geotechnical composites made from contaminated soil and mixed with 25 wt% of immobilization additives and an optimal quantity of water to achieve consistency, at which maximum compaction according to the Proctor Compaction Test procedure can be achieved. The results reveal a positive, time-dependent trend for the immobilization of potentially toxic elements in the composite with paper ash, because of the formation of the new hydration products with potentially toxic elements. In a composite containing only red mud, potentially toxic elements were immobilized by sorption mechanisms with no general time-dependent trends. The composite with a combination of additives demonstrates the remediation characteristics of both red mud and paper ash. Using this approach excavated contaminated soil, red mud and paper ash can be successfully recycled in the proposed composites, which can be beneficially used in situ for rehabilitation of contaminated sites. Nevertheless, mobilization of some potentially toxic elements at high pHs may represent a limiting factor and has to be taken into the consideration when a combination of red mud and paper ash is used as immobilization additive. (C) 2020 The Authors. Published by Elsevier Ltd.

【 授权许可】

Free