Fluidization characteristics of iron ore powder in fluidized bed

Abstract

The fluidization characteristics of iron powder were studied on a self-made cold fluidized bed in the laboratory. The pressure distributed in the axial inside the lifting pipe of a fluidized bed gradually decreases to a constant value from underbody to roof. As the gas flow rate in the fluidized bed increases, the pressure on each axial section first increases and then decreases. When the inflation numbers are fixed, as the operating gas speed increases, the pressure on the same height segment decreases. When the operating gas speed of a fluidized bed is constant, the pressure increases with the increase of inflation numbers. The pressure at different bed heights is affected differently by the operating air speed: at the underbody of the bed, the pressure rapidly decreases with increasing operating airspeed. As the cross-sectional height increases, the influence of operating gas speed on pressure gradually decreases. As the charge increases, the pressure at the underbody of the fluidized bed rises rapidly, while the pressure at the roof changes gently. When iron ore fine powder is fluidized, distribution in axes of particle concentration shows an uneven distribution of upper dilute and lower dense. Under a certain loading number, increasing the operating airspeed will reduce the average concentration of granules in each axial section of the entire bed, and the particle concentration distribution in that section will become uniform. As the number of charges increases, the average concentration of granules in the riser increases, and the difference in particle concentration between the underbody and roof parts of the riser decreases.