Study on density distribution characteristics and fine coal separation of magnetically fluidized beds of microfine particles

Abstract

ABSTRACT In this paper, the characteristics of the axial and the radial density distribution and the density stability of a gas-solid fluidized bed formed by microfine magnetite powder were studied under different fluidizing gas velocities and magnetic field intensities, and the separation experiments of −6 mm fine coal were carried out. The experimental results show that the axial density of the bed with magnetic field applied is lower than that without magnetic field applied under different gas velocities. The density fluctuation of the gas-solid fluidized bed with magnetic field is smaller than that of the ordinary gas-solid fluidized bed, and the stability of the bed density decreases with the increase of the fluidization number. The experimental results of separation of −6 mm fine coal show that the Ep value increases with the increase of fluidization number. Under the same fluidization number, the Ep value of −6 + 3 mm coal is smaller than that of −3 + 0.5 mm coal. When the fluidization number is 1.1, the Ep value of −6 + 3 mm coal is 0.0375 g/cm3, and the Ep value of −3 + 0.5 mm coal is 0.0475 g/cm3. This shows that the magnetically fluidized bed of microfine particles has a good separation effect for −6 mm coal.