Radial dispersion characteristics of two- and three-phase fluidized beds

Abstract

Radial dispersion coefficients of a continuous liquid phase in two- and three-phase fluidized beds have been studied in a 10.2 cm i.d. column. The coefficients were determined from the radial tracer (KCl) concentration profiles and the use of an infinite space model. Effects of water (4-12 cm/s) and air (0-10 cm/s) velocities and particle size (1.7-6.0 mm) on the radial dispersion coefficient were determined. The mixing intensity of the liquid phase in the radial direction was examined in terms of energy consumption rate. The coefficient increased with the gas velocity and particle size. However, the coefficient exhibited a maximum value at a liquid velocity in two- and three-phase fluidized beds. The coefficient increased with the energy consumption rate in the beds. It was found that the coefficient in terms of the Peclet number is well-represented by the isotropic turbulence model. © 1986 American Chemical Society.