Evaluation of Energy Aspects of Apple Drying in the Hot-Air and Infrared Dryers
Seyed Hashem Samadi and Issa Loghmanieh
DOI : 10.3844/erjsp.2013.30.38
Energy Research Journal
Volume 4, 2013
Drying is an energy-intensive process. In general, heating and evaporation require large quantities of energy. This study has been conducted to evaluate analysis for dying apple slices in two drying systems including hot-air convection and infrared drying. The apple samples were dried at temperatures of 90, 120 and 150°C and radiation intensity of 0.22, 0.31 and 0.49 W/cm2 in the hot-air and infrared dryer, respectively. The results showed that the minimum energy consumed for drying apple slices in infrared dryer was 1 kW h while minimum energy consumption in hot air dryer was 7.02 kW h. Also, the specific energy consumption in IR dying was about 82-86% shorter than that of hot-air drying. The value of SEC of apple under IR and hot air drying was ranged from 110.35 to 71.78 kWh/kgwater and 635.53 to 501.15 kWh/Kgwater, respectively. The calculated value of moisture diffusivity varied from 3.499×10-7-4.746×10-7 m2/sec and 3.671×10-7-5.101×10-7 m2/sec and the value of energy activation were found to be 140.1 and 94.62 kJ moL-1 for IR and hot air drying, respectively. Therefore,one way to improve drying operations is to use infrared energy.
© 2013 Seyed Hashem Samadi and Issa Loghmanieh. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.