ENHANCEMENT OF DRYING RATES FOR SLAB-LIKE MATERIALS IN A FLUIDIZED DESICCANT DRYING MEDIUM

The kinetics of drying of slab-like materials in- mersed in a fluidized bed of silica gel particles at a relatively low temperature, 30 °C, is studied. As a re- sult of desiccant particle action large surface-to-bed moisture fluxes and, consequently, large drying rates are attained. For all examined materials (cardboard, veneer, asbestos and ceramic plates) the drying times in the desiccant fluidized bed are much shorter than those in the empty apparatus with the same air flow, temperature and humidity. A simple, diffusional model of the drying based upon a mean mass capacity concept is developed. The drying curves calculated from the model are in good agreement with the experimental ones.