In the paper, results of investigations of the drying of microspherical capillary-porous particles are presented. Experiments were carried out in a spouted bed wryer with a draft tube. Kinetics of drying of the investigated material was determined. The falling drying rate period is described using Fick's diffusion equation. In this paper, results obtained from the analytical solution of the model are compared with a numerical solution as well as with classic equation and with experimental data.