Modularized dry coal beneficiation technique based on gas-solid fluidized bed

Abstract

A 40–60 t/h modularized dry coal beneficiation process with a novel method to control the bed was designed around a gas-solid fluidized bed separator. Furthermore, the hydrodynamics of medium-solids consisting of wide-size-range magnetite powder (0.3–0.06 mm) and <1 mm fine coal were numerically studied. The simulation results show that the fluidization performance of the wide-size-range medium-solid bed is good. The separation performance of the modularized system was then investigated in detail using a mixture of <0.3 mm magnetite powder (mass fraction of 0.3–0.06 mm particles is 91.38 %) and <1 mm fine coal as solid media. The experimental results show that at separation densities of 1.33 g/cm³ or 1.61 g/cm³, 50–6 mm coal can be separated effectively with probable error, E, values of 0.05 g/cm³ and 0.06 g/cm³, respectively. This technique is beneficial for saving water resources and for the clean utilization of coal.

Keywords

dry coal beneficiation / modularization / gas-solid fluidized bed / wide-size-range medium-solids

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