Catalysts and Batteries Recycling to Produce Ferroalloys and High‐Speed Steel. Issue 4 (23rd September 2022)

• Record Type: Journal Article
• Authors: Rocabois, Philippe; Dufour, Jean-Pierre; Dimet, Arnaud; Baret, Raphaël; Chorlet, Stéphane
• Other Names: Asnafi Nader guestEditor.
• Is Part Of: Steel research international. Volume 94:Issue 4(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-23
• Subjects: batteries -- catalysts -- high-speed steel -- recycling; Steel -- Periodicals; Steel -- Metallurgy -- Periodicals; 669.142
• DOI: 10.1002/srin.202200384
• Languages: English
• ISSNs: 1611-3683

Abstract

Abstract : To decrease its CO2 emission and environmental footprint, Erasteel produces its high‐speed steel using 90% recycled materials and targets to increase this ratio even further. The remaining 10% are mainly metallic oxides (V2 O5, MoO3 ), ferroalloys (FeW, FeCr, FeSi), and cobalt. The total life assessment shows that producing from 100% recycled material leads to reducing CO2 emission by 96%. The high‐value metallic alloys are sourced from spent catalysts, scraps, metallic oxides, or carbides. Used catalysts contain Mo, W, and Co elements that are directly used as raw material in high‐speed steel containing cobalt. The metals contained in the spent catalyst (Ni, Co, Mo) are recycled with specific equipment: a patented roaster to eliminate the sulfur and hydrocarbides, submerged electrodes electric furnace to separate metals and minerals and to obtain ferroalloys, an argon oxygen decarburization reactor to remove impurities and reduce oxides by aluminum or ferrosilicon additions. The elements contained in the batteries: Ni, Mn, and Zn, are separated by pyrometallurgy in an electric arc furnace to produce ZnO powder, MnO‐rich slag, and ferronickel alloys, the three of them used as raw material by metallurgical industries. Abstract : To produce high‐speed steel and ferronickel for the stainless‐steel industry (photo), recycling uses catalysts and batteries by pyrometallurgy leading to the reduction of CO2 emission by more than 80%, compared to primary alloy production. The recycled yield is the highest obtained: over 90% for the high‐value alloying elements such as Mo, Ni, Co, or Zn.