SOLIDS MIXING AND SEGREGATION IN A GAS-LIQUID-SOLID FLUIDIZED-BED

Experiments were conducted to study the solids mixing and segregation behavior in a gas-liquid-solid fluidized bed containing a binary mixture of the particles. Particles with different diameters but similar density were employed in the experiments. Multiple shutter plates were used for bed isolation to determine axial variation of the bed properties including concentrations of particles in the binary mixture, and liquid and gas holdups. A mathematical model which takes into consideration two counteracting mechanisms previously reported for solids mixing and segregation behavior in the liquid-solid fluidized bed system was developed to account for the same behavior in gas-liquid-solid fluidized bed system. An empirical approach established by R. H. Jean and L. -S. Fan was employed in this study to permit solids holdups in the three phase fluidized bed system to be readily predicted based on the equation of J. F Richardson and W. N. Zaki for two phase fluidized bed systems.