A NATURAL CONVECTION SOLAR DRYER FOR ROUGH RICE | ||||
| Misr Journal of Agricultural Engineering | ||||
| Article 12, Volume 28, Issue 1, January 2011, Page 201-215 PDF (714.22 K) | ||||
| Document Type: Original Article | ||||
| DOI: 10.21608/mjae.2011.105394 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
| A. M. Kishta1; M. A. Tawfik2; H. M. El-Shal2 | ||||
| 1Assistant prof. Dept. of Agric. Eng., Fac. of Agric. Zagazig Univ., Egypt. | ||||
| 2Lecturer, Dept. of Agric. Eng., Fac. of Agric. Zagazig Univ., Egypt. | ||||
| Abstract | ||||
| A solar drying system was constructed and tested to dry rough rice grains for seeding under Zagazig city prevailing weather conditions. The system consists of two integrated units, a solar collector with total area of 1.8 m2 attached to a drying chamber. The system is classified as a natural convection indirect passive cabinet type without any moving parts. The study parameters included varying the air inlet area from 244 to 732 cm2, testing three levels of initial moisture contents (20, 22, and 25% w.b.), and two different grain layer thicknesses of 5 and 10 cm. The system was operated from 8 AM to 5 PM under Zagazig local conditions (Latitude 30.5° N) for 2 weeks during the rice harvesting season of 2009. The results showed that the smallest air inlet area of 244 cm2 gave the highest collector thermal efficiency, the highest temperature difference between ambient air and heated air inside the collector, and highest drying rate. Also the initial moisture content of 20% w.b. gave the highest drying rate and fastest drying time. Same results were found using layer thickness of 5 cm. So the combination of 244 cm2 air inlet area, 5 cm layer thickness, and 20% initial moisture content is recommended for the best thermal performance and highest drying rate. | ||||
| Keywords | ||||
| solar energy; indirect passive cabinet; rough rice; natural convection; drying rate; thermal efficiency | ||||
| References | ||||
|
Awady, M. N.; M. A. El-Nono; E. A.El-Sahhar and A. J. Aboud. 2003. Application of solar energy for drying animal wastes. The 11th annual conference of MSAE, 15-16 Oct., 2003.
Awady, M. N.; S. A. Mohamed; El-Sayed, S. A. and A. A. Hassanain. 1993. Utilization of solar energy for drying process of agricultural products. Misr J. Agric. Eng. 10(43): 794-804.
Brooker, D. B.; F. W. Bakker-Arkema and C. W. Wall. 1978. Drying cereal grains. AVI publishing Co., Wesport, Connecticut, USA.
Farhang, A.; A. Hosinpour, H. Darvishi; M. H. Khoshtaghaza and T. Tavakolli Hashtjin, 2010. Accelerated drying of alfalfa (Medicago sativa L.) by microwave dryer. Global Veterinarians, 5(3): 158-163.
Green, G.M and D. Schwarz.2001.Solar Drying Technology for Food Preservation (GTZ-GATE), August, 8 pp.
Simate, I. N. 2001. Simulation of the mixed-mode natural-convection solar drying of maize, Drying Technology, 19(6) 1137–1155.
Inprasit, C.; A.Noomhorm. 2001. Effect of drying air temperature and grain temperature of different types of dryer operation on rice quality. Drying Technology 19 (1), 389–404.
Zaman, M. A. and B. K. Bala.1989. Thin layer solar drying of rough rice, Sol. Energy, 42 167–171.
Miramare, T. 1997.Design and measured performance of a solar chimney for natural-circulation solar-energy dryers, Renewable Energy, 10(1) 81–90. | ||||
|
Statistics Article View: 132 PDF Download: 290 |
||||
