Aplicação de dois modelos difusivos para a descrição da secagem de bagaços de Umbu.

Abstract

This work was carried out with the objective of providing a description of the drying process of umbu bagasse through diffusive models. For this, the Analitical software (Costa et al. 2020) was used to apply the analytical solution for the diffusion equation (geometry of an infinite wall) admitting the boundary conditions of the first and third types. In addition, the Lab Fit program was used to obtain the kinetics and drying rate by adjusting the experimental data based on the use of empirical models. Furthermore, an optimization test was carried out with the numerical solution for the diffusion equation, in order to improve the results. To carry out the experiment, the waste was placed in three galvanized wire baskets with blocks approximately 13.59 mm thick. Before starting the experiment, the baskets (with the residues) were weighed in order to know the value of the initial mass of the samples. Soon after, they went to the drying process in an oven with forced air circulation at temperatures of 70, 80 and 90oC. With the results obtained, it was possible to conclude that of these models the one that best described the experiments was the model with the numerical solution in which the variation of the diffusivity and shrinkage of the product is considered.