Most oilseed crushing industries use solvent extraction with commercial hexane to produce crude oils. Desolventization with steam in a desolventizer-toaster (DT) is used to remove the residual solvent from oilseed meals. In this study, a mathematical model is developed to simulate the desolventizing process and analyze the influence of operating variables in continuous equipment. Mass transfer phenomena are outlined to take into account different retention and transport mechanisms. Solvent diffusion through pores from the solid to the vapor phase is analyzed and the contribution of axial dispersion along the bed is evaluated. The final equations describing solvent flow in meal particles and through the desolventizer are solved by numerical techniques. The influence of processing variables such as desolventizing temperature and residence time as well as the effect of some process parameters, like particle size, oil content and void fraction in the bed, on the meal residual solvent is simulated by the model. (C) 2002 Elsevier Science Ltd. All rights reserved.