Fig. 2 compares the fluidization mechanism in a
rotating fluidized bed with that in a conventional fluidized
bed. In a conventional fluidized bed, the air distributor is
mounted horizontally and the powder samples are introduced
onto the distributor. Powders are lifted up by a
vertical airflow (drag force and buoyancy against the
gravity force). In a rotating fluidized bed, powder samples
are introduced inside the air distributor and are forced to
the wall by centrifugal force due to the rotation of the
distributor. Air flows radially inward through the air