THE FINE PARTICLES RESIDENCE IN A POWDER-PARTICLE FLUIDIZED-BED

Residence time distribution of fine particles in a powder-particle fluidized bed was measured by using batch feeding of the fine particles. The effects of the initial fine particle concentration and the size of fine particles on the residence time distribution and on the amount of fine particles remaining in the bed were described. When the initial fine particles concentration was greater than a definite critical value, the initial elutriation rate of fine particles remained constant and equal to a certain limit value. For particles as small as 1 mum, almost all fine partices remained in the bed after 1h operation.