Gas flow pulsation was employed to improve the drying of porous pharmaceutical granules in a cylindrical fluidized bed. In our approach, a fraction of the total flow was oscillating intermittently and periodically, typically at 3 Hz during 2 min and remaining constant during the other 2 min of each 4 min cycle. It was found that such pulsation-assisted fluidization not only shortened the total drying time but also enhanced homogeneity. A transition in fluidization behavior, reflected by a distinct transition in the bed dominant frequencies, was observed.

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