Intermittent Drying of Soybeans in Conical Spouted Beds: Modeling Approach

Intermittentdrying is a promising methodology to conventionaldrying which offers benefits related to energy and better-qualityproducts. However, modeling of this technique remains a challenge.Thus, this study aims to propose a fully predictive model for intermittentdrying in conical spouted bed dryers. A single-phase model is usedto account for the heat and mass transfer on the soybean surface andtheir inside, and the predictions are compared with the experimentalresults. The proposed model provides physically consistent resultsand is coherent with the experimental data, mainly for drying undermoderate air temperatures with moderate and long resting periods.As the average moisture content and the average particle temperatureare estimated based on the spatial discretization used in the numericalsolution, as well as on the boundary conditions adopted, the internalgradients of moisture and temperature are also estimated by the model,thus providing a physically consistent representation of the internalgradient behavior. Therefore, this study describes the successfulapplication of an accurate model for continuous and intermittent drying.Accordingly, it contributes to obtain optimal drying parameters inorder to minimize drying costs and improve product quality.