Effect of pulsation period and microwave power on paddy drying

In this study, the influence of different microwave powers (90, 270, and 450 W) and pulsation periods, i.e., On/Off times (30/60 and 30/120 ss-1) on drying rate and seed breakage of “Nemat” and “Hashemi” paddy varieties” was investigated. According to the results, the Midilli et al.'s model showed the best prediction accuracy for drying rate of the "Nemat" variety in the pulsation period of 30/60. Furthermore, the two-term model was found as the best model for "Hashemi" variety in the pulsation periods of 30/60 and 30/120 and for "Nemat" variety in the pulsation period of 30/120.The 270 W microwave power and 30/120 pulsation period can be recommended as a final conclusion of this study for drying “Hashemi” paddy variety. The breakage percentage at this condition was 19.1%. Breakage percent of the Nemat variety was more than 40% at all of the conducted measurements, indicating that this variety is not suitable for microwave drying. The final concluding massage of this study is that a pre-test should be conducted before applying the microwave for paddy drying.