The effects of liquid(0.03-0.12m/s) and gas(0.04-0.20m/s) velocities, and particle size(0-0.8mm) on the volumetric mass transfer coefficients at the grid zone have been determined in a 0.152m-I.D. 1.8m high Plexiglas column.
The volumetric mass transfer coefficient in the grid zone increases with increasing gas velocity and particle size. However, the coefficient exhibits a maximum value at an optimum bed porosity condition.
The volumetric mass transfer coefficients in terms of the Sherwood number in three-phase fluidized beds have been correlated with the Schmidt number and particle Reynolds number which is related to the energy dissipation rate in the beds based on the local isotropic turbulence theory. Also, the coefficient has been correlated with the experimental variables.