Abstract
This paper presents the results of comprehensive studies of the material composition and form of valuable metals in the tailings of lead-zinc mineral processing plants. The tailings showed stable contents of Pb, Zn, Au, and Ag, offering significant potential for secondary mineral processing. The feasibility of producing lead concentrate enriched in gold and silver using enhanced gravity separation with a Falcon L40 concentrator was experimentally confirmed. Varying process parameters resulted in a stable distribution of valuable components in the concentrate with high reproducibility (SD ≈ 0.04-0.08 g). The experimental studies were carried out using a 25-combination design based on the Taguchi L25 structure, with three repetitions of each regime (N = 75). The initial tailings contained 0.82% Pb, 0.44 g/t Au, and 2.8 g/t Ag. Statistical analysis, ANOVA, regression analysis, and response surface modeling (RSM) were used, yielding R 2 = 0.918. The predicted maximum concentrate yield corresponds to a centrifugal acceleration of approximately 110 G and a solid-to-liquid ratio of approximately 1:2.44. The calculated value of 110 G lies between the experimentally studied levels of 100 and 120 G. In this region, experimental results showed high concentrate yields, while further increases in centrifugal acceleration did not lead to a significant increase. The material balance showed a lead concentrate distribution of 92.3% Pb, 94.0% Au, and 90.2% Ag. Preliminary concentration using Falcon L40 allows efficient redistribution of precious metals into the heavy fraction and can be considered a pre-enrichment stage in combined technologies for processing technogenic raw materials.