COMPARATIVE ANALYSIS OF COAL BENEFICIATION PERFORMANCE IN GAS-SOLID FLUIDIZED SEPARATION BEDS WITH DIFFERENT BED STRUCTURES

Fluidization characteristics and separation properties of fluidized beds with different bed structures were studied. The stability of fluidized beds with different structures decreases with the increase of bed height. The uniformity and stability of density of rectangular fluidized bed is better than that of square and circular fluidized bed at the same bed height. The influence of fine coal content on the density distribution of fluidized bed has little relation with the bed structure. Separation results showed that ash segregation degrees of the three fluidized beds were generally high and the separation effects were good when the static bed height was 130 mm, the fluidization number was 1.5, and the fine coal content was 10%. The rectangular gas-solid fluidized bed has the best separation effect: the lowest ash content of cleaned coal is 20.11% and the probable error Ep is 0.11g/cm3. Its Ep value is significantly better than that of square fluidized bed (Ep=0.155 g/cm3) or circular fluidized bed (Ep=0.16 g/cm3).