Experimental Study of a Heat Pump Assisted General Purpose Tray Dryer with Backup Heater

Nidhin A R, M A College of Engineering, Kothamangalam; Dr. Jeoju M Issac ,M A College of Engineering, Kothamangalam; Gokul G Nair ,M A College of Engineering, Kothamangalam; Swagath V Mohan ,M A College of Engineering, Kothamangalam; Feizal Fidus ,M A College of Engineering, Kothamangalam

Heat Pump, Tray Dryer, Drying Uniformity, Drying Rate, Drying Time

Drying is probably one of the oldest methods of food preservation. The tray dryer is widely used in a variety of applications because of its simple design and capability to dry products at high volume. A drying system incorporating the HP (heat pump) was designed and constructed, along with necessary instrumentation to gather data on the properties of process air as well as real-time weight of the material being dried (mango slices). Drying was carried out in three different temperatures 50, 55 and 600C. The design of the system allowed for conducting drying with recirculation of air as well as use of backup electrical heaters. Comparisons of all three cases were made and it was found that drying time decreases with increase in temperature. Also drying rate increases with temperature. In terms of energy consumption, the process of HP assisted drying is more expensive, but drying time justifies its cost.
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Paper ID: GRDJEV02I060024
Published in: Volume : 2, Issue : 6
Publication Date: 2017-06-01
Page(s): 30 - 35