Drying kinetics of pineapple agro-industrial residues: a new approach

Drying kinetics of pineapple agro-industrial residues was studied using thin-layer of product at 40°C, 50°C, 60°C and 70°C, and airflow rate of 1.5 m/s. The diffusion model was modified and fitted to experimental data of moisture ratio of pineapple residue to estimate the diffusion coefficient as function of temperature, and a good fitting of Arrhenius equation was obtained, with a variance explained of 99.98 %. Values of diffusion coefficients varied in the range from 4.82 × 10−10 m2⁄s to 11.17 × 10−10 m2⁄s, approximately. A modification was implemented in the Page’s equation to include the diffusion effects explicitly, leading to a less empirical and simpler model to describe drying kinetics of pineapple residue. The model presented in this work proved to be adequate to predict drying ratio of pineapple residue, if the material layer thickness is 1.0 cm, under the drying conditions used.