Document Type : Research Paper

Abstract

Several methods are used to decrease seed drying time and enhance the quality of dried seeds. In
fluidization methods, good aeration occurs during the drying process. In this research, conditioned seeds
with 20% d.b. moisture content were dried at 30°, 40°, 50° and 60°C using three bed conditions (fixed,
minimum fluidized, fluidized). All experiments were done using a batch-type fluidized bed dryer and three
replications. Temperature and bed changes in the dryer on canola seed drying kinetics were investigated.
The cultivating properties of dried seeds, such as final germination percentage, emergence percentage,
seedling leaf area index and seedling dry mass percentage were compared with naturally dried seeds as a
control. Experimental results showed that temperature and seed bed changes had significant influences on
the canola seed drying process. Suitable aeration was observed during and after minimum fluidized bed
drying, which may save energy during the drying process. The fluidized seed bed decreased drying time
more than 23% over the fixed bed. The fluidized resulted in about an 8% increase in drying time over the
semi-fluidized seed bed. When the use of high temperature is limited for drying, fluidization at moderate
temperatures can a suitable alternative for drying heat-sensitive materials. Drying at 30° and 40°C using
semi-fluidized beds is a good choice for drying canola seeds. It did not have harmful effects on the canola
seed cultivation properties and kept them within standard limits.

Keywords

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