Juckamas Laohavanich

pp. 343 - 348

Abstract

Wet Paddy (KDML 105 variety) was dried under different process conditions applying a pilot scale experimental gas-fired infrared dryer. The infrared radiation is expressed in terms of peak wavelength of infrared emitter, and the initial moisture content of paddy were varied to study the drying behavior. Five existing mathematical models describing thin layer
drying have been investigated. The experimental results were compared considering their goodness of fit in terms of coefficient of determination, R², root mean square deviation, RMSD, and Chi-square, χ². The available thin layer drying models were fitted to the drying data resulting in the Modified Page Model being chosen, with a high average value of R² =0.9952. This model was considered to be best fitted over other models, because it gave the lowest RMSD and χ² values, which were compared between the observed and predicted moisture ratios. A combined regression equation was developed to predict the drying parameters k and n, which gave a good fit, with R²=0.9635 (k) and R²=0.9328 (n). 

Keywords

• gas-fired infrared
• paddy drying
• modeling