Study on the Drying Characteristics of Agricultural Products During Fluidized Bed Drying - Drying Characteristics of Green Onion and Onion During Fluidized Bed Drying -

농산물의 유동층 건조특성 연구 - 파 및 앙파의 유동층 건조특성 -

  • Lee, G.H. (Division of Agricultural Engineering, Kangwon National University)
  • Published : 2006.10.25


Drying characteristics of green onion and onion during fluidized and fixed bed drying were investigated and compared. Sliced peen onion and onion were dried at drying air temperature of 45, 55, and $65^{\circ}C$. Drying air velocity during fluidized bed drying was adjusted with drying time at each drying temperature. Drying time to reach a given final moisture content was shorten in fluidized bed drying than in fixed bed drying - for drying temperature of 45, 55, and $65^{\circ}C$, the differences were 60, 60, and 50 min for green onion and 360, 180, and 60 min for onion. Drying constant (K) was greatly affected by drying method and drying temperature. Terminal velocity under fluidized bed drying was decreased exponentially for green onion and linearly (or onion with increase of drying temperature. Also, terminal velocity had linear relationship with moisture content for both green onion and onion.


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