Contact drying of mechanically agitated particulate material in the presence of inert gas

Abstract A model permitting the calculation of drying rates during contact drying of mechanically agitated particulate material in the presence of inert gas is introduced. The so-called penetration theory is used to calculate the heat transfer from the heating surface to the bed. The mixing intensity is described with an empirical parameter, the mixing number N mix . Calculated drying rate curves are compared with drying rates measured in three different disc dryers.