TY - JOUR

T1 - Investigation of the Impact of Biochar Application on Foaming Slags with Varied Compositions in Electric Arc Furnace-Based Steel Production

AU - Kieush, Lina

AU - Schenk, Johannes

N1 - Funding Information: Support 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, is gratefully acknowledged. Additionally, Voestalpine Stahl GmbH, Linz, Austria, is gratefully acknowledged for providing samples for this research. The support from Heng Zheng (Montanuniversitaet Leoben) during this research is gratefully appreciated. Publisher Copyright: © 2023 by the authors.

PY - 2023/8

Y1 - 2023/8

N2 - This paper investigates the influence of biochar, either as an individual component or in combination with high-temperature coke, on the slag foaming behavior. High-temperature coke serves as a reference. Three scenarios were considered to study the slag foaming behavior, each characterized by different slag chemical compositions. The results indicate that biochar can promote steady foaming for specific slags when the basicity (CaO/SiO2) falls within a range of 1.2 to 3.4. Experimental findings also reveal that stable foaming can be achieved when a mixture containing biochar and coke with a ratio of 1:1 is employed, with a minimum slag basicity of 1.0 and FeO content of 25 wt.%. The foaming range obtained using different FeO contents (15 wt.% to 40 wt.%) in the mixture surpasses the range observed with the individual application of coke or biochar. The X-ray diffraction (XRD) analysis showed that unrelated to the carbon source applied, the general pattern was that the phases larnite (Ca2SiO4) or dicalcium silicate were detected for slag foams with high basicity. Monticellite (CaMgSiO4) and magnesium iron oxide (Fe2MgO4) were predominant in slag foam samples, with the highest MgO content. The presence of monticellite and merwinite (Ca3MgSi2O8) occurred in samples with the lowest basicity. Eventually, the application of the mixture of coke and biochar showed the potential to obtain stable foaming across a wide range of slag compositions.

AB - This paper investigates the influence of biochar, either as an individual component or in combination with high-temperature coke, on the slag foaming behavior. High-temperature coke serves as a reference. Three scenarios were considered to study the slag foaming behavior, each characterized by different slag chemical compositions. The results indicate that biochar can promote steady foaming for specific slags when the basicity (CaO/SiO2) falls within a range of 1.2 to 3.4. Experimental findings also reveal that stable foaming can be achieved when a mixture containing biochar and coke with a ratio of 1:1 is employed, with a minimum slag basicity of 1.0 and FeO content of 25 wt.%. The foaming range obtained using different FeO contents (15 wt.% to 40 wt.%) in the mixture surpasses the range observed with the individual application of coke or biochar. The X-ray diffraction (XRD) analysis showed that unrelated to the carbon source applied, the general pattern was that the phases larnite (Ca2SiO4) or dicalcium silicate were detected for slag foams with high basicity. Monticellite (CaMgSiO4) and magnesium iron oxide (Fe2MgO4) were predominant in slag foam samples, with the highest MgO content. The presence of monticellite and merwinite (Ca3MgSi2O8) occurred in samples with the lowest basicity. Eventually, the application of the mixture of coke and biochar showed the potential to obtain stable foaming across a wide range of slag compositions.

KW - biochar

KW - coke

KW - electric arc furnace

KW - slag foaming

KW - X-ray diffraction analysis

UR - http://www.scopus.com/inward/record.url?scp=85170552659&partnerID=8YFLogxK

U2 - 10.3390/en16176325

DO - 10.3390/en16176325

M3 - Article

AN - SCOPUS:85170552659

VL - 16.2023

JO - Energies

JF - Energies

SN - 1996-1073

IS - 17

M1 - 6325

ER -