A correlation of the elutriation rate constant for adhesion particles (group C particles)

The elutriation of fine particles (groups C or A particles) from a fluidized bed of fine–coarse particle mixtures was investigated at steady state. FCC and alumina particles were used as fines, Alumina, FCC, PVC, SiC and silica sand particles (groups A or B particles) were used as coarse particles, respectively. The elutriation rate constant of group C particles (adhesion particles) decreased with increases in the mean diameter of bed particles and with decreases in the size of elutriated particles under the condition of a constant superficial gas velocity. This finding is quite different from that of elutriation of groups A or B particles. The elutriation rate constant of group C particles was hardly affected by the density of coarse particles in the bed. To correlate the elutriation rate constant for adhesion particles, the particle size coefficient (Cps) is introduced. Empirical equations of elutriation rate constant for cohesive particles were obtained. The proposed correlation well predicts the values of elutriation rate constant of cohesive particles.