National University of Science and Technology “MISIS”, Moscow, Russia

N. A. Maslennikov, Assistant Professor, Department of Mineral Processing and Industrial Waste Recycling, masl.nik2000@gmail.com
D. V. Zinoveev, PhD (Eng.), Associate Professor, Department of Mineral Processing and Industrial Waste Recycling, dmitry@zinoveev.ru
Yu. V. Konyukhov*, Dr. Sci. (Eng.), Head of Department of Mineral Processing and Industrial Waste Recycling, ykonukhov@misis.ru

Wai Zin Kyaw, PhD Student, Department of Mineral Processing and Industrial Waste Recycling, waizinkyaw.yo@gmail.com

A. A.Baikov Institute of Metallurgy and Materials Science, Russian Academy of Sciences, Moscow, Russia
M. A. Fedotov, Senior Researcher, Laboratory of New Metallurgical Processes and Alloys, Mikle_fed@mail.ru

Branch of National Research University “MPEI” in Tashkent, Tashkent, Uzbekistan
M. V. Kravchenko, PhD (Eng.), Director, Kravchenkomv@mpei.ru

*Corresponding author

The production of high-quality iron concentrates suitable for the metallurgical industry from low-grade hematite ores is a challenging scientific and technical task. This paper presents the results of beneficiation of a low-grade hematite ore using a flowsheet based on hydrogen magnetizing roasting at 375 °C, followed by wet magnetic separation and reverse flotation. Furthermore, the effectiveness of using a vortex layer apparatus for grinding the magnetized ore is demonstrated. A concentrate with an iron content of 64.93 % and a recovery of 98 % was obtained. The proposed flowsheet can be used to produce high-quality iron concentrates via roasting-magnetic beneficiation from low-grade hematite ores and iron-rich wastes, aiming to reduce overall carbon dioxide emissions across the steel production chain.
This research was funded by the Russian Science Foundation (project No. 24-29-00672).

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