Wilde and Broqueville [13] reported their experimental investigations of rotating fluidized bed in a static geometry. The fluidization gas was tangentially injected via multiple gas inlet
slots in a cylindrical outer wall; this induced a rotating motion. Radial fluidization of the solids was created by introducing a radially inwards motion of gas towards a centrally positioned chimney, through which it exited finally. They reported that stable rotating fluidization was obtainedwhensolids loading was sufficiently high. In a multi-stage vortex combustor for burning rice husk, Eiamsaard et al.