HEAT AND MASS TRANSFER CHARACTERISTICS OF INTERMITTENT PADDY RICE DRYING:EXPERIMENTAL AND THEORETICAL STUDY
Intermittent drying of paddy rice is fully investigated both theoretically and experimentally.A model was developed to represent simultaneous heat and mass transfer for drying stages and mass transfer for tempering one.The model is considered for both cylindrical and spherical coordinates assuming non-constant paddy rice physical properties.Further,a set of experiments are designed and carried out in a lab-scale fluidized bed dryer to estimate the moisture diffusivity of rice and to evaluate the effects of different parameters.The model estimates show good agreement with experimental data.Cylindrical model slightly better fits the experimental results specially after tempering stage.Simulation results reveal that thermal equilibrium is rapidly reached within the first two minutes.Air velocity shows to have no significant effect on drying rate when fluidization condition is prevailed.In addition,drying rate is drastically improved after applying tempering stages as a result of moisture gradient removal.
paddy rice intermittent dying coupled model concentration profile
M.Assar M.Golmohammadi M.Rajabi-Hamane S.J.Hashemi
School of Chemical Engineering,College of Engineering,University of Tehran P.O.B.11155-4563,Tehran,Iran
国际会议
The 18th International Drying Symposium Conference(第十八届国际干燥学术大会(IDS2012))
厦门
英文
1-9
2012-01-11（万方平台首次上网日期，不代表论文的发表时间）