liquid diffusion model for thin-layer drying of rough rice

• Published in: European food research & technology 2008-02, Vol.226 (4), p.787-793
• Main Authors: Hacihafizoğlu, Oktay, Cihan, Ahmet, Kahveci, Kamil, de Lima, Antonio G. B
• Format: Article
• Language: English
• Subjects: Agriculture; Air temperature; Analytical Chemistry; Biological and medical sciences; Biotechnology; Cereal and baking product industries; Cereals; Chemistry; Chemistry and Materials Science; Diffusion coefficient; Drying; Food engineering; Food industries; Food Science; Forestry; Fundamental and applied biological sciences. Psychology; General aspects; Geometry; Grain; Humidity; Liquid diffusion; Moisture content; Original Paper; Physicists; Power supply; Prolate spheroid; Rice; Simulation; Steel pipes; Studies; Temperature; Thin-layer; Velocity
• ISSN: 1438-2377; 1438-2385
• DOI: 10.1007/s00217-007-0593-0

In this study, the drying behavior of single-layer rough rice with a moisture content of between 22 and 24% on the dry basis was simulated by means of a liquid diffusion model, based on a prolate spheroid geometry. For this purpose, the solution of liquid diffusion equation was fitted to the experimental moisture ratios for drying air temperatures between 40 and 60 °C and velocity 1.5 m s-¹. In order to make a comparison, the predictions of liquid diffusion equations for a spherical and finite cylindrical geometry were also fitted to the experimental results. Modeling was performed by selecting the diffusion coefficients in diffusion equations in such a manner as to minimize the sum of the squared differences between the experimental results and the theoretical predictions. It was found that the liquid diffusion model, based on a prolate spheroid geometry, explains single-layer drying behavior of rough rice well. It was also found that the model, based on a prolate spheroid geometry, has better agreement with the experimental results than the other geometries.