Bahavior of Powders in a Packed Bed with Lateral Inlets

This study is to clarify the flow characteristics and hold up behavior of powders in a packed bed with lateral inlets through which gas and powders are injected. The experiments were carried out for two kinds of the packed particles and powders. Longitudinal and radial distributions of powder hold up as well as longitudinal distribution of pressure in the packed bed were measured. It was found that more powders deposited in the lower part, especially in the lower central part of the packed, bed and that the total hold up of powders increased with the increase in the diameter of the packed particles. No blockade occurred for powders of 98 and 175μm under the experimental conditions. The gas and powder two-phase flow in the packed bed was simulated by a two-dimensional mathematical model considering gravitational force, the interaction forces between gas and the packed particles, gas and powders, and powders and the packed particles. The effect of static hold up of powders on the voidage of the packed bed was reflected in computations through the trial and error approach according to the experimental data of total hold up of powders. The pressure distribution computed by the mathematical model has good agreement with the observed one, and so that the static and dynamic hold ups of powders obtained are reasonable.