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Environmental beneficiation of Kalmakyr Copper-Molybdenum ore by Pre-flotation Gold-Silver Gravity Recovery

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Author Affiliations

  • 1Department of Engineering Communication, Tashkent University of Architecture and Civil Engineering, Tashkent, Uzbekistan
  • 2Department of Mining, Almalyk State Technical Institute, Almalyk, Uzbekistan
  • 3Department of Mining, Almalyk State Technical Institute, Almalyk, Uzbekistan

Int. Res. J. Environment Sci., Volume 15, Issue (4), Pages 66-74, October,22 (2026)

Abstract

Improving recovery of valuable metals before tailings generation is an important component of resource-efficient mineral processing. This study evaluates the environmental significance of pre-flotation gravity recovery from Kalmakyr copper-molybdenum ore, Uzbekistan, by comparing a laboratory 30-KS shaking table with an FLSmidth Knelson KC-MD3 centrifugal concentrator. The assessment combines metallurgical performance with screening indicators relevant to environmental management: concentrate mass pull, gold and silver recovery, metal upgrading, and preservation of copper in the downstream flotation feed. Grinding for 20 min produced 70.3% material finer than 0.074 mm. The best tested shaking-table condition, 110 min-1 at 10 mm amplitude, recovered 21.91% Au and 24.60% Ag into 1.20% of the feed mass and preserved 99.55% of Cu in the gravity tailings. The 65 G Knelson condition recovered 24.94% Au and 20.80% Ag into 0.92% of the feed mass while preserving 99.27% of Cu. Gold upgrade ratios were 18.3 for the shaking table and 27.1 for the Knelson concentrator; corresponding silver upgrade ratios were 20.5 and 22.6. Thus, a small pre-flotation concentrate captured approximately one-fifth to one-quarter of the gravity-responsive precious-metal inventory without substantial copper diversion. This result indicates a resource-conservation opportunity and a potential reduction of valuable-metal loading to final tailings. Because electricity, water, reagent consumption, and final flotation-tailings quality were not measured, the study presents an environmental screening rather than a complete life-cycle assessment.

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