Engineering company TOREX, Yekaterinburg, Russia

V. V. Bragin, Cand. Eng., Technical Director, e-mail: v.bragin@torex-npvp.ru

University of Science and Technology “MISIS”, Moscow, Russia
A. M. Bizhanov, Cand. Eng., Leading Expert, e-mail: abizhanov@jcsteele.com

Engineering company TOREX, Yekaterinburg, Russia¹ ; Ural Federal University named after of the first President B. N. Yeltsin, Yekaterinburg, Russia²
I. S. Bersenev, Cand. Eng., Associate Prof.², Head of Dept.¹, e-mail: i.bersenev@torex-npvp.ru

Lomonosov Moscow State University, Moscow, Russia
M. S. Chernov, Cand. Geol.-Miner., Researcher, e-mail: chernovms@my.msu.ru

Nowadays, production of the iron ore briquettes is becoming one of the rapidly developing process trend of pelletizing which is substantiated by advantages from the perspective of reduction of greenhouse gases and harmful emissions when using briquettes. Metallurgical properties of iron ore feedstock are being determined by its porous structure, therefore study on modifying the briquette porosity under reduction is a relevant issue which is eventually an objective of this paper. The briquettes produced from pellets fines have been introduced as the subject of research, alongside with a liquid glass, polymer and DR pellets. It was revealed that the value of briquette porosity accounts for 35-37 %, while the corresponding value of reduced pellets accounts for 37-43 %; porosity of oxidized pellets is 24 % and the reduced pellets are comparable with reduced briquettes. In the course of reduction, a proportion of pores less than 10 μm (by 10 % and higher) is getting reduced due to consolidation of voids and rise of pore proportion with the size of 10-100 μm. Max size of pores in the briquettes is smaller than ones in the pellets. The maximum size of the pores during the reduction of the pellets is getting smaller and in the course of the briquette reduction - it’s getting bigger. Polymer binder facilitates an increase in porosity of briquettes which helps to increase its reducibilityThe reduced briquettes and pellets have a similar porosity, therefore it’s anticipated to get similar values in terms of strength in the shaft furnace. Briquettes are not supposed to deteriorate a pellet bed structure in the metallization shaft furnace.

1. Kapelyushin Yu. E. Comparative review on the technologies of briquetting, sintering, pelle tizing and direct use of fines in processing of ore and technogenic materials. CIS Iron and Steel Review. 2023. Vol. 26. pp. 4–11.
2. Kurunov I. F., Chizhikova V. M., Bizhanov A. M. Best available techniques in the production of agglomerated raw materials for blast furnaces. Chernaya metallurgiya. Byulleten nauchnotekhnicheskoy i ekonomicheskoy informatsii. 2018. No. 1 (4). pp. 62–66.
3. Lotosh V. E., Okunev A. M. Non-roasting agglomeration of ores and concentrates. Moscow : Nauka, 1980. 216 p.
4. Levchuk K. Vale intends to launch production of “green” briquettes in 2023. Available at: https://gmk.center/news/vale-namerena-v-2023-godu-zapustit-proizvodstvo-zelenyh-briketov/ (accessed: 06.12.2024).
5. Magdziarz A., Kuźnia M., Bembenek M., Gara P. Briquetting of EAF dust for its utilisation in metallurgical processes. Chemical and Process Engineering. 2015. Vol. 36, Iss. 2. pp. 263–271.
6. Bizhanov A., Pavlov A., Chadaeva O., Dalmia Y. et al. High temperature reduction of the stiff vacuum extrusion briquettes under the ITmk3 conditions. ISIJ International. 2014. Vol. 54, Iss. 6. pp. 1450–1452.
7. Alvarez F. J. R., Nuevo F. P., Sanchez F. J. P., Tulipanes F. Patent of USA, No. 10815548. Method for producing briquettes from pellet fines, DRI sludge, DRI fines and dust from DRI dedusting systems, for industrial use in direct-reduced iron production processes. Applied: 21.09.2017. Published: 27.10.2020.
8. Official website of Vale: Iron Ore Briquettes. Available at: https://vale.com/iron-ore-briquettes (accessed: 06.12.2024).
9. Babanin V. I., Eremin A. Ya., Bezdezhskii G. N. Development and introduction of a new technology for briquetting finely divided materials with sodium silicate. Metallurgist. 2007. Vol. 51. pp. 66–71.
10. Reinisch G. Vale’s cold iron ore briquettes an innovative solution. Arab Steel Summit and International Iron and steel Exhibition, Doha, Qatar, 14-15.10.2024. Available at: https://events.aisusteel.org/wp-content/uploads/2024/10/Guilherme_VALE.pdf (accessed: 06.12.2024).
11. Mousa E., Ahmed H., Söderström D. Potential of alternative organic binders in briquetting and enhancing residue recycling in the steel industry. Recycling. 2022. No. 7. p. 21.
12. Somerville M. A. The strength and density of green and reduced briquettes made with iron ore and charcoal. Journal of Sustainable Metallurgy. 2016. No. 2. pp. 228–238.
13. Wen Y., Tichang S., Zhenzhen L., Jue K. et al. Effects of particle sizes of iron ore and coal on the strength and reduction of high phosphorus oolitic hematite-coal composite briquettes. ISIJ International. 2014. Vol. 54, No. 1. pp. 56–62.
14. Han H., Duan D., Yuan P. Binders and bonding mechanism for RHF briquette made from blast furnace dust. ISIJ International. 2014. Vol. 54. No. 8. pp. 1781–1789.
15. Korchevsky A. N., Zvyagintseva N. A. Experimental studies of the technology of briquetting iron-containing waste from metallurgical production. Gorny informatsionno-analiticheskiy byulleten. 2019. No. 9. pp. 122–130. DOI: 10.25018/0236 1493-2019-09-0-122-130
16. Ying Li, Yonggang Zang et al. Effect of briquetting pressure on the properties, reduction behavior, and reduction kinetics of cold-bonded briquette prepared from return fines of sinter. Metallurgical and Materials Transactions B. 2022. Vol. 54, Iss. 1. pp. 1–15.
17. Manyuchi M., Mbohwa Ch., Muzenda E. Value addition of coal fines and sawdust to briquettes using molasses as a binder. South African Journal of Chemical Engineering. 2018. Vol. 26. pp. 70–73.
18. Rizos V., Tuokko K., Behrens A. The circular economy: A review of definitions, processes and impacts. Available at: https://www.ceps.eu/ceps-publications/circular-economy-reviewdefinitions-processes-and-impacts/ (accessed: 06.12.2024).
19. Wu Sh., Chang F., Zhang J., Lu H. et al. Cold strength and high temperature behaviors of selfreducing briquette containing electric arc furnace dust and anthracite. ISIJ International. 2017. Vol. 57, Iss. 8. pp. 1364–1373.
20. Cavaliere P. et al. Hydrogen direct reduction and reoxidation behaviour of high-grade pellets. International Journal of Hydrogen Energy. 2024. Vol. 49. Part C. pp. 1235–1254.
21. Aaro L.-E. LKAB performance in ironmaking. Chernye Metally. 2015. No. 12. pp. 61–62.
22. Tran Thi Thu Hien, Tran Ngoc Hung, Tran Trung Hai. Effect of binders on reduction degree of iron ore pellets. Materials Today: Proceedings. 2022. Vol. 66. Part 5. pp. 2844–2848. DOI: 10.1016/j.matpr.2022.06.527
23. Cavaliere P., Sadeghi B., Dijon L., Laska A. et al. Three-dimensional characterization of poro sity in iron ore pellets: A comprehensive study. Minerals Engineering. 2024. Vol. 213. 108746.
24. Gruzdev A. I., Bersenev I. S., Chernov M. S. et al. Study of the structure of the pore space of iron ore pellets using computer tomography. Stal. 2024. No. 11. pp. 2–11.
25. Wang J., Ma P., Meng H., Cheng F. et al. Investigation on the evolution characteristics of bed porous structure during iron ore sintering. Particuology. 2023. Vol. 74. pp. 35–47. DOI: 10.1016/j.partic.2022.05.005
26. Tang K., Wang Y., Niu Y., Honeyands T. A. et al. Particle classification of iron ore sinter green bed mixtures by 3D X-ray microcomputed tomography and machine learning. Powder Technology. 2023. Vol. 415. pp. 118–151. DOI: 10.1016/j.powtec.2022.118151
27. Bersenev I. S., Vokhmyakova I. S., Borodin A. V. et al. Formation of structure and metallurgical properties of partially reduced pellets. Stal. 2022. No. 10. pp. 2–6.
28. Bizhanov A. M. Models of optimal packaging in problems of determining the porosity of agglomerated products. Metallurg. 2024. No. 8. pp. 91–96.
29. Reed S. J. B. Electron microprobe analysis and scanning electron microscopy in geology. Moscow : Tekhnosfera, 2008. 232 p.
30. Trofimov V. T., Korolev V. A., Voznesensky E. A., Golodkovskaya G. A., et al. Soil Science. 6th edition revised and enlarged. Moscow : Izdatelstvo MGU, 2005. 1024 p.
31. Sokolov V. N., Yurkovets D. I., Razgulina O. V., Melnik V. N. Study of solids microstructure characteristics using computer analysis of SEM images. Izvestiya RAN. Seriya fizicheskaya. 2004. Vol. 68. No. 9. pp. 1332–1337.
32. Bulygina L. G., Sokolov V. N., Chernov M. S. et al. Analysis of soil structure using a scanning electron microscope – X-ray computed microtomograph (SEM-μCT) complex. Geoekologiya. Inzhenernaya geologiya, gidrogeologiya, geokriologiya. 2014. No. 5. pp. 457–463.
33. GOST 17212–84. Iron ores, agglomerates and pellets. Method for determination of reductibility. Introduced: 01.01.1986.
34. Ji G., Xiao C., Gao Xu, Zhou Y. et al. Migration behavior of iron and phosphorus during gas-based reduction for high-phosphorus iron ore. Minerals Engineering. 2024. Vol. 213. 108765. DOI: 10.1016/j.mineng.2024.108765
35. Bhatti S. A., Qiao X. Synergistic effect of carbothermal reduction and sodium salts leaching in the process of iron recovery from copper slag. Process Safety and Environmental Protection. 2025. Vol. 193, Iss. 1. pp. 170–182.
36. Vitikka O., Iljana M., Heikkil A. et al. Cold compressive strength of iron ore pellets in distinct reduction stages. Powder Technology. 2025. Vol. 451. 120478. DOI: 10.1016/j.powtec.2024.120478
37. Geeders M., Chaigneau R., Kurunov I. et al. Modern blast furnace ironmaking: an Introduction. Moscow : Metallurgizdat, 2016. 280 p.
38. Gorbachev V. A., Shavrin S. V. Nucleation in the oxide reduction processes. Responsible editor E. A. Pastukhov. Moscow : Nauka, 1985. 134 p.
39. Bersenev I.S., Bragin V. V., Gruzdev A. I. et al. Features of the iron ore pellets structure depending on the concentrate enrichment degree. Steel in Translation. 2023. Vol. 53. No. 4. pp. 328–335.
40. Karabasov Yu. S., Chizhikova V. M. Physicochemistry of iron reduction from oxides. Moscow : Metallurgiya, 1986. 199 p.