Study on key factors affecting separation performance of aerated fluidized bed

Abstract

ABSTRACT Although extensive research has been done on improving the separation performance of coarse coal in the minerals processing industry, there is still a gap between the current recovery of the coarse coal and the optimal separation performance. We developed a lab-scale aerated fluidized bed in this paper to investigate the effects of slurry concentration, superficial water velocity, aeration rate, concentration of frother and concentration of collector on the separation performance of coarse coal (1–0.125 mm). The aerated fluidized bed has an inside diameter of 0.15 m, a total height of 0.85 m, and a cross-sectional area of 0.018m2. The test result showed that the ash separation degree increased initially and then decreased with the increase of slurry concentration, aeration rate, superficial water velocity, concentration of frother and concentration of collector, respectively. The optimal separation performance was achieved in an aerated fluidized bed under the conditions of 500g/L slurry concentration, 30mm/s superficial water velocity, 0.36 m3/h aerated rate, 0.06285mmol/L concentration of frother, and 200g/t-coal concentration of collector. Compared to the conventional liquid-solid fluidized bed, the use of the aerated fluidized bed in this study produced a much higher yield of clean coal, reduced tailings, and achieved 29.12% higher recovery of coarse particles.