FLOW CHARACTERISTICS OF THE LIQUID-SOLID CIRCULATING FLUIDIZED-BED

A new fluidization regime, the circulating fluidization regime, is ide ntified for the upwards liquid-solid fluidization operation. This circ ulating fluidization regime is characterized by non-uniform radial dis tribution of liquid velocity, particle velocity and particle hold-up i n the bed, different from the conventional fluidization regime and the transport regime where the radial flow structure is more uniform. Bec ause of the radial non-uniform flow structure, the flow behaviours in the circulating fluidization regime cannot be predicted with the empir ical relationships based upon homogeneous fluidization.