South Ural State University (National Research University) (Chelyabinsk, Russia)

K. I. Smirnov, Researcher, Lab. of Hydrogen Technologies in Metallurgy, e-mail: smirnovk@susu.ru
P. A. Gamov, Cand. Eng., Associate Prof., Acting Head of the Lab. of Hydrogen Technologies in Metallurgy
V. E. Roshchin, Dr. Eng., Prof., Chief Researcher, Lab. of Hydrogen Technologies in Metallurgy, e-mail: roshchinve@susu.ru

The results of theoretical analysis and experimental studies of selective solid-phase Fe reduction from an ilmenite concentrate by carbon or hydrogen are presented. It is shown that hydrogen reduces Fe with a higher rate at a relatively low (900 °C) temperature, what allows to obtain soft iron and titanium dioxide concentrate, which are easily separated by melting and are commercial products. Hydrogen is practically not dissolved in solid iron, and is easily removed from the unit due to the gaseous state, what eliminates titanium reduction and formation of its lower oxides when the temperature rises at the stage of separation of the reduction products. Fe reduction by carbon at an acceptable rate and at a higher (above 1100 °C) temperature is accompanied by reduction of titanium to lower oxides, while energy consumption for reduction increases by 2.25 times. The scheme is proposed for processing of ilmenite concentrate in a non-agglomerated form – selective reduction of iron with hydrogen in a multi-hearth furnace, with consequent separation of reduction products into soft iron and titanium dioxide concentrate in a plasma furnace.
The study was supported by the Russian Science Foundation (grant no. 23-29-10119, https://rscf.ru/project/23-29-10119/).

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