TY - THES

T1 - Hydrometallurgical extraction of valuable metals from electric arc furnace dust originated in stainless steel production

AU - Howard, Thomas Wolfgang

N1 - no embargo

PY - 2024

Y1 - 2024

N2 - Regarding the growing production rates of metals, there is also a direct proportional increase in the accumulation of corresponding by-products like dust. These often contain, as in the case of stainless steel production, valuable metal like Cr, Ni, and Mo, which would be lost if no actions would be taken. To counteract the resulting dependency on imports, material loss, economic and ecological effects, the interest in recycling of those residues has grown in the last decade. Though most industrially applied processes recover these metals from dust by pyrometallurgical means, the research in hydrometallurgical methods to recover metals has gained attention. This is due to the flexibility of such solutions in dealing with inhomogeneous input materials and the ease with which they can be adapted in their design. Therefore, a new hydrometallurgical approach in the extraction of Cr and Ni by dissolving stainless steel dust in five different acids has been conducted in the course of this thesis. Through these leaching experiments, the knowledge of the need for harsher conditions, like higher temperature, longer leaching time and higher acidity has been gained. Simultaneously, an optimized setup for such conditions was developed, that counteracts the disadvantages which were noticed while conducting the experimental campaigns. Based on these results and optimizations, future campaigns with and without pre-treatment of dusts to recover valuable metals by leaching and following precipitation steps, are in development.

AB - Regarding the growing production rates of metals, there is also a direct proportional increase in the accumulation of corresponding by-products like dust. These often contain, as in the case of stainless steel production, valuable metal like Cr, Ni, and Mo, which would be lost if no actions would be taken. To counteract the resulting dependency on imports, material loss, economic and ecological effects, the interest in recycling of those residues has grown in the last decade. Though most industrially applied processes recover these metals from dust by pyrometallurgical means, the research in hydrometallurgical methods to recover metals has gained attention. This is due to the flexibility of such solutions in dealing with inhomogeneous input materials and the ease with which they can be adapted in their design. Therefore, a new hydrometallurgical approach in the extraction of Cr and Ni by dissolving stainless steel dust in five different acids has been conducted in the course of this thesis. Through these leaching experiments, the knowledge of the need for harsher conditions, like higher temperature, longer leaching time and higher acidity has been gained. Simultaneously, an optimized setup for such conditions was developed, that counteracts the disadvantages which were noticed while conducting the experimental campaigns. Based on these results and optimizations, future campaigns with and without pre-treatment of dusts to recover valuable metals by leaching and following precipitation steps, are in development.

KW - Hydrometallurgie

KW - Rückstandsaufbereitung

KW - Gewinnung von Wertmetallen

KW - Elektrolichtbogenofenstaub

KW - Edelstahlwerkstaub

KW - Hydrometallurgy

KW - Residue processing

KW - Extraction of valuable metals

KW - Electric arc furnace dust

KW - Stainless steel mill dust

U2 - 10.34901/mul.pub.2024.096

DO - 10.34901/mul.pub.2024.096

M3 - Master's Thesis

ER -