Conventional (anthracite, calcined petroleum coke, and coke) and non-conventional (biochar, and biocokes (3 wt.% torrefied wood, and 3 wt.% petroleum coke + 3 wt.% charcoal)) carbon-bearing sources have been studied for their use in electric arc furnace (EAF)-based steel production. Commonly, for the use of carbon sources in EAFs, one of the important properties is the content of fixed carbon, the release of volatiles as well as the elemental composition of inorganics. The properties of six carbon sources were analyzed by determining the proximate analysis, X-ray fluorescence analysis (XRF), coke reactivity index (CRI), and strength after reaction with CO2 (CSR), Brunauer–Emmett–Teller (BET) specific surface area and Barrett–Joyner–Halenda (BJH) pore size and volume analysis, ash chemical analysis, optical and scanning microscopy, Raman spectroscopy and X-ray diffraction (XRD) analysis. The results indicate biocoke as a promising option to replace conventional carbon-bearing sources. In the sample set, the fixed carbon, volatiles, and ash content of the biocokes were similar despite the total difference in additives. Additionally, the use of additives did not significantly affect the biocoke reactivity indices, but slightly decreased the strength after the reaction with CO2. Carbon-bearing sources have been characterized in terms of their structural properties. XRD analysis revealed that the amount of disordered carbon increased in the order: coke < calcined petroleum coke ~ biocoke (3 wt.% torrefied wood) < biocoke (3 wt.% petroleum coke + 3 wt.% charcoal) < biochar. The results obtained on the physical, chemical, and structural properties of carbon sources are the basis for further research on the behavior of slag foaming.
Bibliographical noteFunding Information:
This research was supported by the scholarship program “Scholarship of the Scholarship Foundation of the Republic of Austria, Postdocs,” [MPC-2022-02241], financed by the Federal Ministry of Education, Science and Research of Austria, which is gratefully acknowledged. Stahl-und Walzwerk Marienhütte GmbH, Graz, Austria; Voestalpine Stahl GmbH, Linz, Austria; and ThyssenKrupp Steel Europe AG, Duisburg, Germany are gratefully acknowledged for providing the sample materials for this research. The authors are also grateful to the reviewers for their insightful comments and efforts in improving the manuscript.
© 2023 by the authors.
- calcined petroleum coke
- EAF-based steel production