The influence of particle mechanical properties on bubble characteristics and solid mixing in fluidized beds

Abstract

To determine the influence of interparticle forces on the fluid mechanics of large particle fluidized beds, experiments were conducted using particles with different values of the friction coefficient and the coefficient of restitution. The bubble characteristics and particle dispersion within the bed were measured. The bed characteristics were found to be insignificantly influenced by changes in friction and coefficient of restitution, indicating that either interparticle mechanical forces due to direct contact are unimportant or that these forces are only influenced by the particle size, density and velocity. The wake fraction was found to be a strong function of particle size. The upward particle transit velocity is proportional to the mean bubble frequency. Downward transit velocity is proportional to the volumetric flow rate of bubbles and the wake fraction.