Numerical and experimental analysis of the heat and mass transfer during okara drying

The aim of this study is to model the heat and mass transfer during the okara drying. Okara, containing 77% of moisture content (w.b.), was extruded in the shape of spherical pellets and then dried in a fixed bed dryer until 3% of moisture content (w.b.). During the process, the okara moisture and temperature profiles were experimentally obtained. The governing equations of heat and mass transfer (Fourier and Fick, respectively) were solved by the Implicit Finite Difference Method. The thermophysical properties of okara which were necessary in the numerical model were obtained from correlations that require the okara centesimal composition and some variables measured during the process. The numerical results were compared to the experimental ones, presenting a reasonable adjustment.

► Okara in the shape of spherical pellets was dried in a fixed bed dryer.
► Governing equations of heat and mass transfer were solved by the Implicit Finite Difference Method.
► Thermophysical properties were obtained from correlations using centesimal composition.
► Numerical results when compared to experimental data show good agreement.