Siberian Federal University (Krasnoyarsk, Russia):

N. V. Vasyunina, Cand. Eng., Associate Prof.
I. V. Dubova, Cand. Eng., Associate Prof.

T. R. Gilmanshina, Cand. Eng., Associate Prof., Head of the Dept. of Technosphere Safety of Mining and Metallurgical Production, e-mail: gtr1977@mail.ru

Elkor JSK (Krasnoyarsk, Russia):
K. E. Druzhinin, Director

Cand. Eng., Associate Prof. A. A. Kovaleva participated in this research.

High-iron Bayer red mud, including more than 30 % Fe, is considered as poor iron ore. Owing to global iron deficiency during last decades, the problem of efficient use of iron which is containing in red mud with high Fe content attracts most and most attention. This research includes development of the technological route for Fe extraction from red mud in cast iron via reduction smelting with consequent accelerated cooling for metal separation from slag. Influence of different experimental parameters (such as temperature, basicity and reduction time) on Fe extraction from red mud was examined in details. The results displayed that separation between metal and slag was complete. Maximal Fe extraction in cast iron was obtained at the temperature 1450 °С and made in average 88.5 % (when using fluxes without soda) and 91.5 % (with soda addition). Microstructure of the samples was determined, it showed the structure of hyper-eutectic white cast iron (ledeburite + graphite). No non-metallic inclusions were revealed in the structure of samples. Optimal experimental results are very important for achievement of large-scale and highefficient red mud recovery.

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