Azerbaijan Technical University (Baku, Azerbaijan)

A. T. Mammadov, Dr. Eng., Prof., Advisor of the Dept. “Metallurgy and Materials Technology”, e-mail: ariff-1947@mail.ru
S. N. Namazov, Dr. Eng., Prof., Dept. “Metallurgy and Materials Technology”, e-mail: subhan.namazov@aztu.edu.az
A. I. Babayev, Cand. Eng., Associate Prof., Head of the Dept. “Metallurgy and Materials Technology”, e-mail: aqil.babayev@aztu.edu.az
M. Ch. Huseynov, Cand. Eng., Associate Prof., Dept. “Metallurgy and Materials Technology”, e-mail: muxtar.53@mail.ru, muxtar.huseynov@aztu.edu.az

This paper examines innovative processes for the direct reduction of sponge iron (DRI) and its use in electric steelmaking production. The primary raw material for iron reduction is iron ore from the Dashkesan deposit in the Republic of Azerbaijan. The chemical composition of Dashkesan iron ore is presented, along with the degree of metallization of this raw material. Data are provided on the extent of carbon, phosphorus, sulphur, and non-ferrous metal removal from the ore. It was found that in the process using a gaseous reductant, “sooty” carbon is deposited from the gas phase onto the developed surface of the DRI. The removal of phosphorus during direct reduction is not feasible; therefore, before this operation, deep beneficiation of ores intended for direct reduction is necessary. The main source of sulphur in DRI is the reductant. When using a solid reductant, the sulphur content is high, so in this case, flux (limestone, dolomite) must be added to the charge. When using a gaseous reductant, the sulphur content in the product is low. The content of non-ferrous metals, nitrogen, and hydrogen in metallized pellets is low. A relationship between the apparent density and porosity of briquettes, ores, and pellets has been established. High porosity is observed in pellets, which is related to the porosity of the initial iron ore and the reduction in oxide volume during reduction. The quality of the steel produced is greatly affected by the secondary oxidation of DRI. Due to its highly developed surface and high porosity, DRI is prone to secondary oxidation during transportation and storage. Therefore, studies were conducted to reduce the level of secondary oxidation, and a passivation technology was developed to protect the iron from further oxidation.

The authors declare that they have no conflict on interest in relation to this research, whether financial, personal, authorship or otherwise, that could affect the research and its results presented in this paper This work was supported by the Azerbaijan Science Foundation – Grant № AEF-MCG-2023-1(43)-13(01)1-M-01.

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