Drying Characteristics of Fine Powders in an Inert Medium Circulating Fluidized Bed

摘要

The effects of inlet gas velocity(1.53-1.75 m/s),inlet gas temperature(50-80°C),mass ratio between fine powder and inert particle(F/I ratio,0.05-0.2)and initial water content(8.5-31.6 wt%,wet basis)on the drying rate were determined in an inert medium circulating fluidized bed(0.085 m ID X 1.0 m high).Glass beads(d_p=327.5 nu m,rho_s=2,500 kg/m3)as inert particles and poly methyl methacrylate(PMMA)beads(d_p=12.5 mu m,rho_s=1,190 kg/m3)as fine powders were used.The drying rate increases with increasing inlet gas temperature,gas velocity and the F/I ratio.The effect of initial water content on the drying rate was negligible compared with the other variables.The obtained drying rate data have been correlated with inlet gas temperature,gas velocity,F/I ratio,and the initial water content.