Life cycle assessment of a novel production route for scandium recovery from bauxite residues

Type
01A - Journal article
Editors
Editor (Corporation)
Supervisor
Parent work
Cleaner Waste Systems
Special issue
DOI of the original publication
Link
Series
Series number
Volume
7
Issue / Number
100129
Pages / Duration
Patent number
Publisher / Publishing institution
Elsevier
Place of publication / Event location
Edition
Version
Programming language
Assignee
Practice partner / Client
Abstract
Scandium (Sc) has various technological applications, but the concentrations of Sc in ores are low. Both, the mining of low concentrated Sc and the production of industrial-grade Sc are a heavy burden on the environment. Bauxite residue (BR) from alumina production represents one of the major sources of Sc in Europe (Ochsenkühn-Petropulu et al., 1994). The goal of this study is to assess the environmental impacts from cradle to gate of a novel production route developed in the Scandium Aluminium Europe project (SCALE) to extract Sc at concentrations <100 ppm from BR, to concentrate and upgrade it to pure ScF3 and Sc2O3 and ultimately to refine it to an aluminium scandium master alloy with 2 % Sc mass fraction (AlSc2 %). Results show that the global warming potential (GWP), measured in CO2-eq per kg Sc2O3, generated with the novel route is about half the GWP of the state-of-the-art Sc2O3 production from rare earth tailings when applying equal allocation principles. The initial process step to dissolve BR and extract Sc consumes elevated amounts of acid and energy and is responsible for at least 80 % of the route’s total environmental impact. The amount of the generated filter cake (FC) is equal to the amount of the BR input and is a potential resource for cement clinker production. The ecotoxicological study indicates that both FC and BR are slightly ecotoxic.
Keywords
Resource assessment, Secondary raw materials, Bauxite residue, Life cycle assessment, Scandium
Project
Event
Exhibition start date
Exhibition end date
Conference start date
Conference end date
Date of the last check
ISBN
ISSN
2772-9125
Language
English
Created during FHNW affiliation
Yes
Strategic action fields FHNW
Publication status
Published
Review
Peer review of the complete publication
Open access category
Gold
License
'https://creativecommons.org/licenses/by/4.0/'
Citation
Hengevoss, D., Misev, V., Feigl, V., Fekete-Kertész, I., Molnár, M., Balomenos, E., Davris, P., Hugi, C., & Lenz, M. (2024). Life cycle assessment of a novel production route for scandium recovery from bauxite residues. Cleaner Waste Systems, 7(100129). https://doi.org/10.1016/j.clwas.2024.100129