Exergetic analysis of deep-bed drying of rough rice in a convective dryer

This research work was aimed at a detailed exergy analysis of paddy deep-bed drying process in a laboratory-scale convective dryer. The drying experiments were conducted at different inlet drying air temperatures and flow rates, and exergy loss, exergy destruction, exergy efficiency, improvement potential rate and sustainability index were investigated. Normalized exergy destruction of the process ranged from 1.67 to 7.46. Exergy efficiency of the drying process and drying chamber was specified to be in the ranges of 5.10-29.41% and 32.64-67.75%, respectively. The results indicated that applying higher drying air temperatures resulted in higher exergy efficiencies. The obtained improvement potential rates showed that the process is highly capable of ameliorating exergy performance improvement. The sustainability index of drying process ranged from 1.05 to 1.42, augmenting with the increase in the air temperature.