A Comparative Study on Exergetic Efficiencies of Two Different Drying Processes
Makaleler > Tam Makale · 2008
Yazarlar: Filiz İÇİER, Neslihan ÇOLAK, Zafer Erbay, Ebru Hancioğlu, Arif Hepbaşlı
\n Volume: 4, Issue: 3\n 279-284\n \n, Uluslararası, 2008, cilt 4, ss 279-284
Özet
Food drying is an energy-intensive process. Its energy consumption accounts for 7-15% of the total energy consumption in all industries in developed countries and its thermal efficiency generally varies from 25 to 50%. In this context, studies conducted have focused on improving the efficiencies of processes and drying equipment. Exergy analyses can reveal whether or not and by how much it is possible to design more efficient thermal systems by reducing the sources of existing inefficiencies. In this study, two different food drying systems, tray dryer and fluid-bed dryer systems, were analyzed and compared using energy and exergy analysis methods for performance evaluation purposes. Since the drying of medical and aromatic plants has gained a big importance in the recent years, parsley was selected as the drying material. Drying temperature was in the range of 40-60°C, while drying air velocity varied from 0.5 to 1.5 m/s in the tray drier, and 1.7 to 3.7 m/s in the fluid bed drier. Although fluid bed drying was faster than tray drying for parsley, the exergy efficiency of tray drying was higher than that of fluid bed drying for each temperature and air velocity values studied. Higher temperature and lower velocity led to higher exergy and energy efficiencies in both drying methods. It may be concluded that exergy analysis method may be applied as the effective tool in assessing the performance of various drying processes similar to energy analysis.