Conventional and intermittent drying modeling of agricultural products: A review

The purpose of this article is to present a discussion about recent technologies applied to processes involving intermittent drying of agricultural products, in addition to verifying the adjustment of mathematical models, both for conventional and intermittent drying, based on recent research in the literature. It was found that new mathematical models are being studied to describe the drying kinetics, one of which is the generalized Lewis model. Regarding intermittent drying, mathematical models are generally based on mass and energy balances. Furthermore, to obtain the mathematical modeling of intermittent drying for intermittent products, some researchers employ the effective diffusivity technique to describe all possible mechanisms of moisture movement, being estimated by Fick's second law of diffusion. Energy savings were also analyzed for different raw materials, ranging from 6% to 75%. It has been shown that the tempering time, and the conditions of the samples under study, affect energy consumption.