Axial mixing and segregation of multicomponent coarse particles fluidized by concurrent gas-liquid flow

Abstract

Multicomponent solid particles were fluidized by upward concurrent flows of air and water in vertical columns of 7 cm diameter and 4.85 m height, and of 15 cm diameter and 2.7 m height. Solid particles used were sieved glass beads (2.2, 3.1 and 4.65 mm) and mixtures thereof. Axial changes in holdups of gas and solids were determined by sectioning the whole column simultaneously with horizontal plates. The solid holdup of coarse particles was more strongly affected by the liquid velocity than was that of fine particles. A one-dimensional sedimentation-dispersion model was applied to describe the axial holdup profile of each solids component. Calculated results were in agreement with experimental ones over an entire column consisting of dense and dilute regions. Parameters used in the calculation were correlated as experimental equations.