Abstract: Aiming at the problems of high proportion of fine-grained tailings (-0 .025 mm content≥ 90%)and difficult recovery of molybdenum from a molybdenite concentrate tailings in Henan Province，cy⁃ clone-static microbubble flotation column was used to carry out fine-grained enhanced recovery test and industrial application research.The suitable process parameters were determined by single factor condition test in the laboratory:flotation time was 13 min，circulation pressure was 0.10 MPa，foam layer height was 25 cm，self-priming air inflow was 0.3 m3/h (opening 2/3)，copper inhibitor TT-1 dosage was 20 g/t.Un⁃ der this condition，the grade of molybdenum concentrate was 1.94%and the recovery rate was 79.65%. Based on Box-Behnken design，a quadratic regression model of molybdenum recovery rate was estab ⁃ lished.Variance analysis showed that the model was significant.The influence weight of factors is circulat⁃ ing pressure>foam layer height>flotation time.The average recovery rate of molybdenum obtained by the op ⁃ timization verification test was 80.62%，which was in good agreement with the predicted value.The results of 14 consecutive shifts in the industrial test showed that after the optimization of the flotation column pro ⁃ cess，the molybdenum grade of the molybdenum concentrate tailings decreased from 0.470%to 0.165%， the actual recovery rate increased to 88.15%，and the crude recovery rate of molybdenum sulfide reached 89.63%.This technology provides a feasible solution for the efficient recovery of fine-grained refractory mo ⁃ lybdenite and has a good application prospect.

Key words: molybdenite, cyclonic-static micro-bubble flotation column, industrial application, regression model