Mining Institute, Far Eastern Branch of RAS (Khabarovsk, Russia):
Alekseev V. S., Senior Researcher, Candidate of Engineering Sciences, alekseev-vs_83@mail.ru
Banshchikova T. S., Senior Researcher

Against the backdrop of decreasing alluvial gold resources, subsoil users are forced to process refractory placer deposits, often containing significant amounts of fine-grained gold and heavy minerals. Their processing without magnetic separation leads to process machine blockages with heavy washings and increased gold losses both when the feed is processed in the field and during the final treatment of the concentrates in placer gold-concentrating plants. The mineralogical analysis of tailings samples obtained after the final treatment of the sluice concentrate downstream of the placer gold-concentrating plants for the Bolotisty area (in the Khabarovsk Territory) demonstrates that almost 75% of the tailings consist of magnetic and electromagnetic fractions and that the processing circuit must include magnetic separation. Installation of an upgraded magnetic separator allowed significantly reducing the contamination of the concentration table with heavy minerals, largely improving the concentration results. The upgrade is required to minimize the flocculation effects and increase the continuous operation time for the separator. An evaluation of the effectiveness of the magnetic separator demonstrates a reduction in gold losses in the final treatment of concentrates on the concentration table by a factor of 7.8.

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