The effects of liquid and gas velocities and particle size on the individual phase holdups, bed porosity, pressure fluctuations and energy dissipation rate in two- and three-phase fluidized beds have been determined in a 0.376 m-ID x 2.1 m high Plexiglas column.
The gas phase holdup increases with gas velocity but decreases with liquid velocity in two- and three-phase fluidized beds.
The liquid phase holdup and bed porosity increase with an increase in liquid velocity but decrease with an increase in gas velocity in two- and three-phase fluidized beds.
The bed porosity exhibits a minimum value with an increase in gas velocity in the beds of 1.0 and 2.3 mm glass beads but, it increases in the beds of 3.0 mm glass beads.
The standard deviation of pressure fluctuations and the energy dissipation rate increase with an increase in gas and liquid velocities but they decrease in the radial direction of the column in two- and three-phase fluidized beds. However, the effect of liquid velocity on the pressure fluctuation and the energy dissipation rate in two-phase bubble column has been to be insignificant.
The liquid phase holdup and bed porosity in three-phase fluidized beds have been correlated with the experimental variables. The energy dissipation rates in two- and three-phase fluidized beds have been correlated with the dimensionless groups.