Efficiency of magnetic separation in reduction of concentrate yield after float-and-sink separation at the Nakyn diamond-bearing placers

As a result of work of specialists at the Mirny–Nyurba GOK with regard to data of the production procedure design, it is found that in the current operating conditions, the yield of the gravity concentrate after float-and-sink separation of diamond-bearing placer material sent from concentrating mill no. 15 to a refinement workshop at concentrating mill no. 16 exceeds the allowable values by 2.5–3 times. This study describes the comparative estimate of possible upgrading scenarios for the process flowsheet adopted at concentrating mill no. 15, implemented by specialists of the Yakutniproalmaz Institute. The reference scenario was adopted as the current flowsheet, and the alternative scenarios were the tested upgraded processes: magnetic separation of the concentrate of mill no. 15, refinement of the concentrate of mill. no. 15 using drying, X-ray and X-ray luminescence separators; primary treatment of original material on a universal high-production separator with the control of tailings on analogous separators. Based on the obtained results, for the reduction of the load ratio at the refinement workshop of mill no. 16, two-stage magnetic separation is proposed for the concentrate of mill no. 15, which allows: the reduced intake of the concentrate at mill no. 16 by 3.5 times owing to removal of 70% of diamond-bearing material from the sink; the maintained recovery of diamonds (96.64%) at the design level (96,60%).

Nikitina Yu. N., Dvoichenkova G. P., Timofeev A. S. Efficiency of magnetic separation in reduction of concentrate yield after float-and-sink separation at the Nakyn diamondbearing placers. MIAB. Mining Inf. Anal. Bull. 2026;(9):21-39. [In Russ]. DOI: 10.25018/0236_1493_2026_9_0_21.

Yu.N. Nikitina, Researcher, Yakutniproalmaz Institute Joint Stock Company ALROSA (Public Joint Stock Company), 678174, Mirny, Russia,
G.P. Dvoichenkova¹, Dr. Sci. (Eng.), Assistant Professor, Chief Researcher; Professor, Polytechnic Institute (branch) of North-Eastern Federal University named after M.K. Ammosov», 678174, Mirny, Russia, e-mail: dvoigp@mail.ru, ORCID ID: 0000-0002-0940-3880,
A.S. Timofeev¹, Cand. Sci. (Eng.), Senior Researcher, e-mail: Timofeev_ac@mail.ru, ORCID ID: 0000-0002-3382-6007,
¹ Institute of Comprehensive Exploitation of Mineral Resources of Russian Academy of Sciences, 111020, Moscow, Russia.

A.S. Timofeev, e-mail: Timofeev_ac@mail.ru.

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