Mass transfer and concentration boundary layer in a particulate fluidized bed

The aim of this study was to analyze the concentration boundary layer for a comprehensive description of the mass transfer in systems with fluidized particles. Mass transfer from the wall of the column to the fluid in the presence of inert fluidized particles was experimentally investigated using the dissolution method. Experiments were carried out in a column 34 mm in diameter, divided by height into six segments. In all runs, mass transfer rates were determined in the presence of fluidized spherical glass particles 1.10 mm, 1.94 mm and 2.98 mm in diameter, using water as the fluidized medium. The analysis of the boundary layer shows the effect of particles presence on mass transfer in fluidized systems. The theoretical model was established based on boundary layer theory, and the impact of particles on the shortening of the boundary layer length, due to their collision with the wall of the column. The theoretically derived model was compared with experimentally obtained data and with data calculated from available literature correlations. Very good agreement was found between the model, experimental data, and published correlations (especially the correlation by Pickett et al. 12])