One-Dimensional Two-Fluid Model for Pneumatic Drying Wet Alumina Particle

A mathematical model for mass, momentum and heat transfer based on two-fluid flow theory is proposed. The model was applied to the drying process of wet alumina particles in a vertical pneumatic dryer. The model was based on the one-dimensional balance equations for mass, momentum and energy of the gas and dispersed phase, taking into account variations of properties with humidity as well as temperature during drying. The model permitted to illustrate the complex transport phenomena that occur during the process and the profiles of temperature, pressure, moisture content and velocity developed through the dryer. It was solved using three different empirical correlations under two different operating conditions, and the numerical solution of the model shows that using Ranz-Marshall correlation, the heat and mass transfer rates during the whole drying period were predicted very well.