Application of hydrogen technologies in the process of steel smelting from metal waste and granulated iron

The use of hydrogen technologies in metallurgy, especially in the process of melting steel from metal waste and granular iron, is becoming more and more relevant. Hydrogen can replace carbon as a reducing agent, which significantly reduces carbon dioxide emissions and makes the process more environmentally friendly.

The main advantages of hydrogen use include:

1. Reducing of CO2 emissions: Hydrogen, unlike carbon, emits water, not carbon dioxide, which helps reduce the carbon trace of steel production.
2. Improving efficiency: hydrogen technologies can improve the energy efficiency of the melting process, since hydrogen has high heat intensive ability.
3. The use of secondary resources: metal waste and granular iron can be effectively processed using hydrogen, which contributes to saving natural resources and reducing the cost of raw materials.

These technologies are at the stage of active development and implementation, and many companies are already beginning to use hydrogen in their production processes to achieve a more sustainable and environmentally friendly production of steel.

The article examines the issue of improving the efficiency of the melting process in steel production by using hot briquetted iron (HBI) in the charge, which mainly consists of metallic waste. An analysis of the characteristics of the melting process when using a complex charge composition has been conducted. To activate the boiling of the metal bath, it is recommended to introduce carbon-containing raw materials, such as steel scrap, in a volume of more than 80%. It has been established that the use of HBI practically does not reduce the yield of usable metal, which is due to the high content of metallic waste in the charge composition.

At the same time, an analysis is carried out on the influence of silicon and manganese oxidation processes on the purification of liquid steel during the melting of alloyed waste in an electric arc furnace, where they are used as charge materials. Graphs are presented showing the equilibrium concentrations of oxygen and silicon at different temperatures in the Fe–Si–O system. Additionally, a graph is created illustrating the dependence of manganese oxidation products in liquid iron on temperature and manganese concentration in the MnO–FeO alloy. The equilibrium concentrations of oxygen and silicon are determined, considering the liquefying effect of carbon in both the liquid silicate region and the solid SiO₂ region.

Effective oxidation of silicon and manganese during the melting of steel from metallic waste and hot briquetted iron (HBI) contributes to the maximum purification of liquid steel through metal-slag or metal-gas phases. It has been established that during electric steel production, the silicon content is reduced to minimal levels. Therefore, when metallic waste and HBI are used as charge components in the steelmaking process, the silicon oxidation reaction does not reach equilibrium. In the case of an acidic process, silicon oxidation may be followed by silicon reduction at higher temperatures due to the heat of the electric arc (the silicon reduction process), provided that equilibrium oxidation conditions are achieved.

It is recommended to conduct the primary melting process of the charge, which includes metallic waste and hot briquetted iron, in an electric arc furnace. During this period, the melting process focuses on metal purification, sulfur removal, achieving the required chemical composition of steel, and regulating the process temperature. All these tasks are performed simultaneously throughout the entire refining period. After the complete removal of oxide slag, slag-forming mixtures with fluxes are added to the furnace, introducing new slag (carbide or white slag). As the temperature in the furnace bath increases, the equilibrium constant of manganese decreases. Consequently, in the absence of ferromanganese addition to the bath during the final stage of melting, the interaction of manganese in the bath can be used to assess the metal temperature.

The use of hydrogen technologies in the process of smelting steel we will show in detail in the English version of the article, which will be published in the International Scientific Journal of Hydrogen Energy – IJHE.

1. Gorodets V. G., Gavrilova M. N. Steel production in an electric arc furnace. Moscow: Metallurgy, 1986. – 208 p.

2. Efroimovich Yu. E. Optimum electric modes of electric arc steel-smelting furnaces. Moscow: Metallurgy, 1996. – 158 p.

3. Müller F. Electric steelmaking at the beginning of the 21st century // Steel. – 2004. – Issue. 11. – P. 32-36.

4. Yavoyskiy V. I. Theory of steel production processes. Moscow: Metallurgy, 1993. – 450 p.

5. Production of steel castings: textbook. / Kozlov L. Ya., Kolokoltsev V. M., Vdovin K. N. et al.; L. Ya. Kozlov (ed.). Moscow: «MISiS», 2003. – 352 p.

6. Kudrin V. A. Theory and technology of steel production: textbook. Moscow: «Mir», OOO «AST Publishing House», 2003. - 528 p.

7. Gusovsky V. L., Orkin L. G., Tymchak V. M. Methodical furnaces. - Moscow: Metallurgy, 2010. – 430 p.

8. Processes and machines of electrometallurgical production: monograph / Rakhmanov S. R., Topalov V. L., Gasik M. I., Mamedov A. T., Azimov A. A. Baku-Dnepr: «System technologies». – Publishing house «Sabah», 2017. – 568 p.

9. Dunp E., Pardaens S., Freibnuth A. Fachberichte H. // Metallweiterverarbeitund – 2013. – Vol. 21, Issue 10. – P. 777-782.

10. Knep K., Rommerswinkel H. W. Arch. Eisenhwttenwesen. – 2015. – Issue 8. – P. 492-496.

11. Olett M., Gateller K. Clean Steel // Proceedings of the 2nd International Conference in Balatonfred, 2011. – P. 122-137.

12. Sidorenko M. F., Magidson I. A., Smirnov N. A. Scan Inject // 3rd International Conference on Iron and Steel Beneficiation by Powder Injection. – Lulea, 2013. – P. 7/1-7/36.

13. Trubin K. G., Oix G. N. Metallurgy of Steel. – Moscow: Metallurgy, 1997. – 515 p.

14. Efimov V. A.Casting and crystallization of steel. – Moscow: Metallurgy, 2006. – 550 p.

15. Povolsky D. Ya. Deoxidized steels. – Moscow: Metallurgy, 1992. – 207 p.

16. Kudrin V. A. Steel metallurgy. – Moscow: Metallurgy, 1991. – 488 p.

17. Bigeev A. M. Steel metallurgy. – Moscow: Metallurgy, 2007. – 440 p.

18. Bewar J. Fachber. H. // Metallweiterverarbeiten. – 2011. – Issue 1. – P. 56-61.

19. Yashimura M., Yochikawa S. Mitsubishi sted // Mtg. Techn. Rev. – 2010. – Vol. 14, Issue 1-2. – P. 4-11.

20. Abratis H., Langhammer H. J. Radex Kdsh. – 2011. – Issue 1-2. – P. 437-441.

21. Itskovich G. M. Deoxidation of steel and modification of non-metallic inclusions. – Moscow: Metallurgy, 2011. – 306 p.

22. Trubin K. G., Oyks G. N. Metallurgy of steel. – Moscow: Metallurgy, 2004. – 535 p.