Energy and exergy analysis of drying of potash particles in a pulsation-assisted fluidized bed

Potash particles exhibit cohesiveness and hygroscopic behavior in the presence of moisture. During the drying of wet potash particles, solid bridges form, and the agglomeration behavior of such particles reduces the efficiency of drying. In this work, pulsed airflow was employed to break agglomeration and eliminate channeling in a fluidized bed with wet potash particles. The effect of different operating conditions including inlet drying gas temperature (40 C-degrees, 50 C-degrees, and 60 C-degrees) and pulsation frequency (1.0 Hz and 2.0 Hz) on the energy and exergy efficiency of fluidized bed drying of potash particles was investigated. A drying model based on the thin-layer theory was employed to correlate the experimental data of drying of potash particles. The results showed that the highest energy and exergy efficiency of potash drying, 28.6% and 27.8%, respectively, was achieved when the fluidized drying of potash particles was operated at lower temperatures and close to the natural frequency of the fluidized bed system.