Investigation on effective factors in drying time Iranian rice varieties in fluidized bed dryer

ABSTRACT: Inthisresearch effect of threefactors,dryer temperature,rice varietyandfinalmoisture was investigated ondryingtime of different rice varieties. Experimentswere performed byusingafluidized bed dryerthat hadability to control thetemperature anddischargeofinlet airtothedryerchamber. drying of three paddy varieties, Tarom-domsiah, Hashemi and Shirudi, was performed respectively from primary moisture content of 19/38%, 18% and 18% to three levels moisture of 8-10%, 10-12% and 12-14% on dry basis with four temperatures 40, 45, 50 and 55°C.Thedryerinlet airvelocitywas constantly considered 4m/s. Experiments were performedin acompletely randomized design and factorial experiment.The results indicated thatdrying timewith temperature andfinalmoisture contentvaries inverselyand byincrease temperature and final, drying time is reduced.The lowest drying time was obtained by Tarom-domsiah variety among all varieties so that time spent at 40°C was 8.25 hours. Variance analysisofrice varieties, temperature and final effect on drying time showed that treatments and their interaction have significant effect on drying time.