Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia

A. S. Kharchenko, Dr. Eng., Associate Prof., Head of the Dept. of Metallurgy and Chemical Technologies, e-mail: as.mgtu@mail.ru
S. V. Yudina, Postgraduate Student, Dept. of Metallurgy and Chemical Technologies, e-mail: yudinasv1478@mail.ru
S. K. Sibagatullin, Dr. Eng., Prof., Dept. of Metallurgy and Chemical Technologies, e-mail: 10tks@mail.ru

Magnitogorsk Iron and Steel Works, Magnitogorsk, Russia

A. V. Pavlov, Cand. Eng., Head of the Blast Furnace Shop

The operation of a blast furnace of Magnitogorsk Iron and Steel Works, equipped with a conical charging device, was studied when the equivalent surface coke size changed. An increase in coke size was achieved by increasing the content of classes 60–80 and +80 mm. In the base periods, the equivalent surface coke size averaged 53.0 mm, in the experimental periods - 54.7 mm. An increase in the equivalent coke size was ensured under constant loading conditions. Analysis of the research results showed that an increase in the equivalent surface size of coke, in addition to an increase in its cold and hot strength indicators, was accompanied by: improvement of the drainage capacity of coke in the furnace hearth in terms of DMI (increased on average from 163 to 165.5) and carbon solubility in cast iron (decreased on average from 97.5 to 97.4 %); spontaneous redistribution of coke along the throat radius - the ratio of CO₂ content in the central part of the furnace to the ore ridge zone decreased by 21.9 % while the ratio of CO₂ content in the peripheral zone of the furnace to the axial zone increased by 7.0 %. As a result, every 1 % (rel.) increase in the equivalent surface size of coke in the range from 53.0 to 54.7 mm was accompanied by a decrease in specific coke consumption by an average of 0.13 % and a decrease in furnace productivity by 0.59 %. To increase the positive effect of coke size on the results of blast furnace smelting, it is advisable to simultaneously use accompanying measures aimed at realizing the benefits of increasing its gas permeability, one of which may be an increase in the load of the peripheral zone with iron ore raw materials.
The article was prepared with the support of the grant of the President of the Russian Federation No. MD-1064.2022.4.

1. Muchnik D. A., Trikilo A. I., Lyaluk V. P., Kassim D. A. Assessment of the quality of coke as a component of blast furnace smelting technology. Koks i khimiya. 2018. No. 1. pp. 15–21.
2. Gu K., Wu Sh., Kou M., Zhou H. et al. Influence of coke quality on main technical indexes of blast furnace. TMS 2018: 9th International Symposium on High-Temperature Metallurgical Processing. The Minerals, Metals & Materials Series. 2018. pp. 745–752.
3. Schmoe P., Peters M. Coke quality and blast furnace performance. Chernye Metally. 2013. No. 11. pp. 48–57.
4. Kurunov I. F., Emel'yanov V. L., Titov V. N., Kakunin V. V. Effect of coke quality on blast-furnace performance indices. Metallurgist. 2007. Vol. 51, Iss. 11-12. pp. 644–648.
5. Bahgat M., Abdel Halim K. S., El-Kelesh H. A., Nasr M. I. Blast furnace operating conditions manipulation for reducing coke consumption and CO2 emission. Steel Research International. 2012. Vol. 83, Iss. 7. pp. 686–694.
6. Huatao Z., Minghua Z., Ping D. et al. Uneven distribution of burden materials at blast furnace top in bell-less top with parallel bunkers. ISIJ International. 2012. Vol. 52, Iss. 12. pp.2177–2185.
7. Muchnik D. A., Trikilo A. I., Lyaluk V. P. et al. The influence of coke quality on the efficiency of blast furnace smelting in furnaces of different volumes. Koks i khimiya. 2018. No. 7. pp. 23–29.
8. Berkutov N.K., Stepanov Yu.V., Popova N.K. et al. On the relationship between coke quality and the main technological indicators of blast furnace smelting. Stal. 2007. No. 5. pp. 10–13.
9. Dmitriev A. N. Formation of coke quality by changing the composition of the coal charge for coking, the influence of coke quality on its consumption in blast furnace and productivity. Chernaya metallurgiya. Byulleten nauchno-tekhnicheskoy i ekonomicheskoy informatsii. 2018. No. 4 (1420). pp. 40–45.
10. Filatov S. V., Kurunov I. F., Titov V. N., Loginov A. M. Analysis of the influence of coke strength after reaction (CSR) on the blast furnace performance. Stal. 2014. No. 10. pp. 10–14.
11. Sibagatullin S. K., Kharchenko A. S. Use of coke nut in blast furnaces. Magnitogorsk : Nosov Magnitogorsk State Technical University, 2014. 162 p.
12. Kuzin A. V., Khlaponin N. S. Experience in preparing coke for blast furnace smelting. Part 1. Metallurg. 2019. No. 1. pp. 10–16.
13. Kuzin A. V., Khlaponin N. S. Experience in preparing coke for blast furnace smelting. Part 2. Metallurg. 2019. No. 2. pp. 12–18.
14. Kuzin A. V. Use of coke nut in a blast furnace. Metallurg. 2023. No. 1. pp. 21–25.
15. Sibagatullin S. K., Kharchenko A. S., Logachev G. N. The rational mode of nut coke charging into the blast furnace by compact trough-type charging device. The International Journal of Advanced Manufacturing Technology. 2016. Vol. 86, Iss. 1-4. pp. 531–537.
16. Minin S. I., Mironov K. V., Koshkarov D. A. et al. Taking into account the influence of the particle size distribution of coke on its metallurgical value. Koks i khimiya. 2022. No. 9. pp. 10–14.
17. Sibagatullin S. K., Kharchenko A. S., Chevychelov A. V. et al. The influence of coke nut on the filtration of liquid smelting products in a blast furnace hearth. Vestnik Magnitogorskogo gosudarstvennogo tekhnicheskogo universiteta imeni G. I. Nosova. 2010. No. 4 (32). pp. 28–30.
18. Vinogradov E. N., Kalko A. A., Karunova E. V. et al. Characteristics of coke loaded into Severstal`s blast furnaces and features of its behavior in the process of iron smelting. Chernaya metallurgiya. Byulleten nauchno-tekhnicheskoy i ekonomicheskoy informatsii. 2015. No. 7 (1387). pp. 40–45.
19. Park T. Ju., Ko K. H., Lee J. H. et al. Coke size degradation and its reactivity across the tuyere regions in a large-scale blast furnace of Hyundai steel. Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science. 2020. Vol. 51, Iss. 3. pp. 1282–1288.
20. Sibagatullin S. K., Kharchenko A. S., Polinov A. A. et al. Results of joint use of coke nut in a blast furnace while simultaneously improving the quality of skip coke. Vestnik Magnitogorskogo gosudarstvennogo tekhnicheskogo universiteta imeni G. I. Nosova. 2010. No. 2 (30). pp. 24–27.
21. Sibagatullin S. K., Kharchenko A. S. Metallurgical properties of iron ore raw materials: textbook. Magnitogorsk : Nosov Magnitogorsk State Technical University, 2018. 150 p.
22. Vegman E. F., Zherebin B. N., Pokhvisnev A. N., Yusfin Yu. S. et al. Metallurgy of iron. Moscow : Akademiya, 2004. 774 p.