Kinetic modelling of sublimation and vaporization in low-temperature dehydration processes

In this work a kinetic analysis has been carried out under two low-temperature dehydration techniques: freeze-drying and controlled low-temperature va cuum dehydration (CLTVD). The CLTVD process is described as a uniformly retreating ice front (URIF) and a sublimation-vaporization model which considers an additional mechanism for the diffusion of liquid water. A comparative analysis on the basis of mass transfer coefficients according to the proposed model is made. The kinetic parameters obtained were compared and studied in order to deduce conclusions about the convenience of both techniques and the possibilities of each model to describe the process kinetically.