MODELING OF PARTICLE LIQUID HEAT AND MASS-TRANSFER IN MULTIPHASE SYSTEMS WITH THE FILM PENETRATION MODEL

Particle-liquid transport phenomena in multiphase systems were studied by measuring particle-liquid heat and mass transfer coefficients in liquid-solid and gas-liquid-solid fixed and fluidized beds, under the same conditions. The apparent lack of analogy between heat and mass transfers was explained by the film-penetration model. The two parameters of this model, the film thickness and the fractional rate of surface renewal, can be obtained by measuring the mass and heat transfer coefficients. Variations in gas velocity, liquid velocity or radial position have different effects on the film thickness and the fractional rate of surface renewal. The film-penetration model is required for accurate predictions of particle-liquid mass transfer under typical industrial conditions.