FLUIDIZATION CHARACTERISTICS OF A CENTRIF UGAL FLUIDIZED-BED

The centrifugal fluidized bed is applicable to high - gas velocity flu idization of fine Particles, though a channelling or a partial fluidiz ation takes place due to the low bed height. The fluidization behavior in a centrifugal fluidized bed is discussed theoretically, analyzing the pressure drop profile by a partial - fluidization model. The model assumes that the bed consists of a fluidized zone and a fixed zone. T he calculated pressure profiles are compared with those observed for b eds with partitions on the distributor for the variation of areal rati os, charged masses and rotational speeds. The results calculated from the model showed excellent agreement with the experimental results. Th e process of increasing a fluidized zone in a centrifugal fluidized be d is determined. Comparison of the results for glass beads (good dispe rsibility) with those for CaCO3 (poor dispersibility) shows the diffic ulty of uniform fluidization. Higher gas velocities in a few times of u(mf) are necessary for uniform fluidization. The size and physical pr operties of the particles are shown to affect the fluidization behavio r.