Enthalpy-Driven Optimization of Intermittent Drying

Several optimization problems pertinent to intermittent drying of biological materials were analyzed and a tool to resolve each optimization problem was developed. As the product quality is related to the particularities of the thermal treatment, an average enthalpy gain of the product weighted by the maximum enthalpy gain was considered as the objective function to be minimized. A diffusion model was used to estimate the objective function, and process simulations were performed for batch drying of grains in the rotating jet spouted bed. The results show that the optimization of intermittent drying improves considerably the energy performance of such a drying process. Moreover, it offers better product quality due to lower enthalpy gain.