South Ural State University, Chelyabinsk, Russia:

V. E. Roshchin, Dr. Eng., Professor, Chief Researcher, “Hydrogen Technologies in Metallurgy” Laboratory, e-mail: roshchinve@susu.ru
A. D. Drozin, Dr. Eng., Professor, Leading Researcher, “Hydrogen Technologies in Metallurgy” Laboratory
P. A. Gamov, Cand. Eng., Associate Prof., Acting Head of the “Hydrogen Technologies in Metallurgy" Laboratory
K. I. Smirnov, Researcher, “Hydrogen Technologies in Metallurgy” Laboratory

The inevitability of restructuring the existing steel production scheme is substantiated not only under the pressure of environmental requirements for decarbonization, but also by the need to bring steelmaking technologies in line with the level of modern science. It is shown that the electronic theory of oxidation/reduction can become a scientific basis for new technologies for the reduction of metals, which allows to consider the thermodynamic and kinetic conditions of processes from a unified standpoint with partial or complete replacement of fossil carboncontaining reducing agents with hydrogen. Comparison of two well-known options for technologies with zero carbon dioxide emissions – reduction of iron by “green” hydrogen or its production by ore electrolysis – shows a multiple advantage of electrolysis in terms of energy costs and more favorable kinetic conditions for its implementation. It is concluded that when developing an industry development strategy, priority should be given not to the production and use of "green" hydrogen, but to the electrolysis of ore. The use of hydrogen as a reducing agent can be justified in the selective extraction of iron from complex ores in units such as plasma shaft furnaces, plasma reactors, or suspension reduction reactors, in which, along with reduction, nitriding would also take place to convert soft iron into steel.
A. V. Roshchin, Dr. Eng., Associate Prof., Chief Researcher, Dept. of Pyrometallurgical and Foundry Technologies, took part in the work.

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