National Research Tomsk State University, Tomsk, Russia:

I. V. Amelichkin, Junior Researcher
P. S. Shcherbakov, Junior Researcher, e-mail: xcrbgc@gmail.com
V. S. Soloviev, Engineer

National Research Tomsk Polytechnic University, Tomsk, Russia:

D. A. Biryukov, Undergraduate Student

This paper describes a comprehensive study that looked at the zircon concentrate produced by Obukhovsky GOK located in Northern Kazakhstan. The study examined the elemental composition and the size distribution of the primary ore and zircon concentrate. The authors examined possible optimization of the concentrate quality, as well as the applicability of dry magnetic separation. The study proved the efficiency of dry magnetic separation for separation of magnetic impurities. The concentration of zirconium in the concentrate increased up to 39 wt.% (53 wt.% expressed as ZrO₂), whereas zirconium losses were about 4%. The process of magnetic separation was carried out using the EVS-10/5 magnetic separator by Mekhanobr-Tekhnika at the magnetic induction of 1.7 Tesla and the feed rate of 5 g/min. The authors examined the applicability of the flotation process for the separation of non-magnetic components from Obukhovsky GOK’s zircon concentrate. The study was carried out on the laboratory flotation unit FML 1 by Mekhanobr-Tekhnika with oleic acid used as the flotation reagent. The elemental composition of the ore and concentrates was analyzed using the sequential X-ray fluorescence spectrometer XRF-1800. Techniques were examined that help recover zirconium dioxide from Obukhovsky GOK’s zircon concentrate. Sintering techniques were tested when zircon concentrate was sintered with alkali metal fluorides, soda ash and sodium hydroxide. Sodium hydroxide sintering proved to deliver the best recovery rate, with an almost 100% recovery of zirconium into the solution. The sodium carbonate sintering delivered a 56% recovery, while a 7.5% recovery was reached when sintering with sodium and potassium fluorides.
The authors who contributed to this paper include V. I. Sachkov, R. A. Nefedov, R. O. Medvedev, A. S. Sachkova, O. V. Nefedova, D. A. Biryukov.
The authors would like to thank the Tomsk Regional Centre of Shared Knowledge for their support of this research work.

This research was funded by the Ministry of Education and Science of the Russian Federation under the Governmental Assignment no. FSWM-2020-0028.

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