Combustion Behavior of Foundry and Metallurgical Cokes to Diversify Solid Fuel in Cupola for Mineral Wool Production

Sun-Joong Kim

doi:10.7844/kirr.2025.34.6.62

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2025 Vol.34, Issue 6 Preview Page Next Page

Research Paper

Combustion Behavior of Foundry and Metallurgical Cokes to Diversify Solid Fuel in Cupola for Mineral Wool Production 미네랄울 제조용 큐폴라로의 고체연료 다각화를 위한 주물용 및 야금용 코크스의 연소 거동

31 December 2025. pp. 62-69

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Abstract

The transition to a sustainable circular economy necessitates the high-value utilization of slag, with slag wool production emerging as a promising approach. This study investigated the combustion behavior of foundry and metallurgical cokes and derived their combustion rate constants as foundational data for modeling temperature distribution inside a cupola furnace. Combustion experiments were conducted at 1273, 1373, and 1473 K, by first purging with N₂ gas at room temperature, followed by thermogravimetric analysis under dried air flows of 500 and 800 ml/min; post-combustion residues were characterized through X-ray diffraction. The combustion rates of both cokes accelerated with an increase in temperature and oxygen flow; the metallurgical coke exhibited higher reactivity, while the foundry coke possessed a higher calorific value. These findings indicate that foundry coke is a suitable heat source for the cupola. The residues mainly comprised SiO₂ and Al₂O₃, with minor phases such as Fe₂O₃ and CaO. Based on kinetic data, combustion rate constants (k_c) were derived as Arrhenius-type functions of temperature for each flow condition, providing key parameters for developing an internal temperature distribution model for the cupola.

Keywords

Cupola

foundry cokes

metallurgical cokes

Combustion behavior

combustion rate constants

지속적인 자원순환 사회 실현을 위해 철강산업 부산물중 슬래그의 고부가가치 활용법으로 슬래그울 제조 연구가 필요하다. 본 연구에서는 주물용 및 야금용 코크스의 연소 거동을 조사하고 연소속도 상수를 도출하여 큐폴라 내부 온도를 예측하기 위한 모델의 기초 연구에 해당한다. 연소 실험은 상온에서 N₂가스로 분위기 치환후 1273, 1373, 1473K 조건에서 Dried Air (500, 800 ml/min) 분위기에서 열중량분석법으로 분석하고, 연소 후 회수된 회분상을 XRD로 확인하였다. 실험 결과 온도 및 산소 유량 증가에 따라 두 코크스 모두 연소속도가 증가하였으며, 야금용 코크스가 반응성이 우수하였으나 발열량은 주물용 코크스가 더 높아 큐폴라 용융로 열원으로서의 활용 가능성을 보였다. 회분은 주로 SiO₂와 Al₂O₃로 구성되었고 Fe₂O₃와 CaO를 함유하는 상도 미량 포함하는 것으로 확인되었다. 또한 반응 속도 실험 데이터를 기반으로 유량 조건에 따라 각각의 연소속도 상수(k_c)를 온도와의 관계식으로 도출하여 큐폴라 내부 온도 분포 모델 개발에 활용할 수 있는 기초 자료를 마련하였다.

키워드

큐폴라

주물용 코크스

야금용 코크스

연소 거동

연소속도상수

References

Korea Iron & Steel Association, Iron making& Steel making Slag Brochure. https://kosa.or.kr/statistics/fileBoard_view.jsp?index=10159 , October 18, 2025.

Jensen, P. G., Belmonte, L., Solvang, M. et al., 2023 : Quantification of high temperature stability of mineral wool for fire-safe insulation, Journal of Non-Crystalline Solids, 622, pp.122680.

10.1016/j.jnoncrysol.2023.122680

Alves, J. O., Espinosa, D. C. R. and Tenorio, J. A. S., 2015 : Recovery of steelmaking slag and granite waste in the production of rock wool, Materials Research, 18(1), pp.204-211.

10.1590/1516-1439.324414

Yap, Z. S., Khalid, N. H. A., Haron, Z., et al., 2021 : Waste mineral wool and its opportunities—a review, Materials, 14(19), pp.5777.

10.3390/ma1419577734640174PMC8510145

Leth-Miller, R., Jensen, A. D., Glarborg, P., et al., 2003 : Application of a mathematical model of a mineral melting cupola, Industrial & Engineering Chemistry Research, 42(26), pp.6872-6879.

10.1021/ie020449w

Leth-Miller, R., Jensen, A. D., Glarborg, P., et al., 2003 : Investigation of a mineral melting cupola furnace. Part II. Mathematical modeling, Industrial & Engineering Chemistry Research, 42(26), pp.6880-6892.

10.1021/ie030770u

Katz, S., 2004 : Cupola Furnace Computer Process Model (No. Cupola Furnace Computer Process Model-Final repor.), S. Katz Associates, Inc, W. Bloomfield, MI; U. Missouri-Rolla, Rolla, MO; U. Antioquia, Medelin, Columbia. pp.8-12.

Ishiwata, N., Iwai, Y., Murai, R. et al., 2011 : Effect of coke diameter and oxygen concentration of blast on cupola operation, ISIJ international, 51(8), pp.1353-1359.

10.2355/isijinternational.51.1353

Linn, N. N. 2017 : Combustion Behavior of Lumpy Coke Particle under Shaft Kiln Conditions, PhD Thesis, Universitatsbibliothek.

Straka, R. and Telejko, T., 2015 : 1D mathematical model of coke combustion, IAENG Int. J. Appl. Math, 45, pp.245-248.

Georgitzikis, K., D`elia, E. and Garbossa, E., Coking coal: Impact assessment for supply security, European Commission, 2022, JRC129975.

Jinsun Carbon, What is the role of coke in metallurgical process?. https://jinsuncarbon.com/what-is-the-role-of-coke-in-metallurgical-process/, October 10, 2025.

Ohno, K. I., Noda, K., Nishioka, K., et al., 2013 : Combustion rate of coke in quasi-Particle at iron ore sintering process, ISIJ International, 53(9), pp.1588-1593.

10.2355/isijinternational.53.1588

Information

Publisher :The Korean Institute of Resources Recycling
Publisher(Ko) :한국자원리싸이클링학회
Journal Title :Resources Recycling
Journal Title(Ko) :자원리싸이클링
Volume : 34
No :6
Pages :62-69
Received Date : 2025-10-20
Revised Date : 2025-11-18
Accepted Date : 2025-11-24
DOI :https://doi.org/10.7844/kirr.2025.34.6.62

Resources Recycling ISSN:2765-3439(Print) 2765-3447(Online) 자원리싸이클링

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