Modeling and Optimization of Rough Rice Drying under Hot Air-infrared Radiation in a Laboratory Scale Vibratory Bed Dryer

A practical model including a parameter as a function of drying condition were introduced to predict the effect of far-infrared radiation (FIR) in a combined rough rice drying process. Tests were conducted in three replication for four levels of FIR (0, 0.1, 0.2 and 0.3 Wcm-2) and three levels of inlet air temperature (30, 40 and 500C). The results obtained from the simulation of the proposed model demonstrated that the models were capable satisfactorily express the characteristics of drying rough rice in combined dryer. Also due to the effects of combination of hot air and FIR drying technique on drying rates, cracking enhancement ratio (CER), required breaking energy for grain, specific energy consumption (SEC) and optimal method was presented. Combination of hot air at temperature of 40 0C and FIR at intensity of 1000 W.m-2 is the best way to have lowest SEC and highest grain quality point of view.