St. Petersburg State University of Architecture and Civil Engineering (St. Petersburg, Russia):

V. Yu. Golubev, Cand. Eng., Associate Prof., Dept. of Building Materials Technology and Metrology, Technical Director of Polyplast North-West LLC, e-mail: vladimirgolubev@list.ru
I. U. Aubakirova, Cand. Eng., Associate Prof., Dept. of Building Materials Technology and Metrology, e-mail: centeririna@yandex.ru
D. A. Panteleev, Cand. Eng., Associate Prof., Dept. of Building Materials Technology and Metrology, e-mail: dm-pant@yandex.ru
K. A. Shumilov, Cand. Eng., Associate Prof., Dept. of Information Technology, e-mail: shkas56@mail.ru

The mining industry is one of the main branches of activity in Russia, and it affects the economy and technical development of our country. In the Northwestern Federal District (NWFD) of Russia, in particular, on the territory of the Murmansk Region alone, there are several large mining and processing plants (MPPs). The challenges posed by the mining industry in general and the mining and processing industry of the Murmansk region in particular require efficient, prompt and cost-effective solutions. One of these tasks was set by the Olenegorsk MPP (JSC «Olkon»). It produces the product of enrichment of iron-containing ore - iron ore concentrate of wet magnetic separation (IOC WMS), while the main goal of the research was to find a new technical solution that could allow to ship wet IOC WMS, reducing its freezing capacity in the cold season, bypassing the drying process. Tested classic antifreeze additives - antifreezes, which are, among other things, solutions of salts that reduce the freezing point of water, in the dosage range of 0.5 ... 3.0 ... 10.0 % of the weight of the iron ore concentrate. The unsatisfactory nature of the test results was established according to the degree of influence of these classical antifreeze additives on the freezing capacity of the concentrate. Taking into account the peculiarities and specifics of the object of research - IOC WMS with the appropriate size / dispersion and moisture content by weight of 7.8 %, in accordance with the terms of reference of JSC «Olkon», an effective product in relatively small dosages, «Polyground Type 3», has been developed. It significantly reduces the freezing capacity of the concentrate in temperature range -20 ˚С… -25 ˚С. Preliminary operating costs for subsequent pilot-industrial tests have been established, ranging from 0.75 % by weight of «Polyground Type 3» per 1 ton of IOC WMS (from 7.5 kg per 1 ton of IOC WMS), an industrial version of application has been proposed.

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