I. V. Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials of the Russian Academy of Sciences (Kola Science Center), Apatity, Russia:

A. A. Smirnov, Expert, e-mail: smirnov@chemy.kolasc.net.ru
P. V. Ikkonen, Engineer

JSC “TEKhNOINVEST ALYaNS”, Moscow, Russia:
A. V. Koznov, Chief Executive Officer
V. D. Sokolov, Managing Director — Head of a Project

The paper conveys the results of radiation assessment of a comprehensive rare-metal ores processing scheme (the Zashikhinsk ore deposit, Irkutsk region, Russia). The paper thus presents the radiation-hygienic characteristics of the processed products, including final concentrates and tailings, as well as their classification in terms of natural radio-nuclide (NRN) content. It was determined that, according to the material classification, the feed ore is classified as Class III, whilst the zircon and columbite concentrates are classified as Class IV, and final tailings are classified as Class I of NRNcontaining industrial wastes. As the feed ore, and practically all the processed products, including the zircon and columbite concentrates, are classified as materials with an abnormal NRN-content, a consideration was given to the assurance of radioactive safety in further management of the considered products, which is envisaged by normative and legal acts in the sphere of sanitary and epidemiological welfare. Each radionuclide’s contribution to an effective specific activity was assessed.
The work was carried out in the course of large-scale pilot ore processing tests in 2014–2015, as ordered by JSC “TEKhNOINVEST ALYaNS”, within the scopes of R&D activities “The development of industrial technology for producing rare metal and rare earth metal oxides from a collective concentrate in the Zashikhinsk ore deposit, in accordance with the State contracts No. 13411.0924800.05.023 of 18.11.2013 (code “Kolumbit”) and No. 13411.0924800.05.020 of 18.11.2013 (code “Pentaksid”). The tests data were used for a development of technological regulations for designing an industrial processing plant as an integrated part of a mining and processing company.

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