Design, development and evaluation of a continuous plug flow fluidized bed dryer

Document Type : Research Paper

Authors

1 Assistant Department of Agricultural Machinery Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran

2 Pro. Department of Agricultural Machinery Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran

Abstract

In this study, a laboratory scale continuous plug flow fluidized bed dryer was designed and constructed. A backward-curved centrifugal fan with a 4 kW electromotor was selected based on the maximum pressure drop in the minimum fluidization state and the ability to produce the velocity required for fluidization of the most granular agricultural materials. The fluidization chamber was a rectangular cuboid with 100, 8, and 40 cm in length, width and height, respectively. The solid feed system was consisted of a bin, a screw conveyor, and an electromotor-gearbox. The uniform fluidization and appropriate drying confirmed that it is possible to develop the industrial prototype of the dryer based on the laboratory one. The decrease of solid moisture content along the dryer length was nonlinear. Increasing the inlet solid mass flow rate at constant inlet gas temperature and weir height increased the solid moisture content at the outlet and along the length of the dryer.

Keywords

Main Subjects

References

Barbosa-C´anovas, G. V., Ortega-Rivas, E., Juliano, P. & Yan, H. (2005). Food powders. New York: Kluwer Academic/Plenum Publishers.
Bizmark, N., Mostoufi, N., Sotudeh-Gharebagh, R. & Ehsani, H. (2010). Sequential modeling of fluidized bed paddy dryer. Journal of Food Engineering, 101, 303-308.
Cnossen, A. G., Jimenez, M. J. & Siebenmorgen, T. J. (2003). Rice fissuring response to high drying and tempering temperatures. Journal of Food Engineering, 59, 61-69.
Food and Agriculture Organization. (2011). Rice production. Retrieved September 10, 2014, from http://faostat.fao.org.
Gupta, C. K. & Sathiyamoorthy, D. (1999). Fluid bed technology inmaterials processing. CRC Press LLC.
Khanali, M. (2012). Modeling and experimental investigation of continuous plug flow fluidized bed drying of rough rice. Ph. D. dissertation, University of Tehran, Teharn, Iran.
Khoshtaghaza, M. H., Sadeghi M. & Amirichayjan, R. (2007). Study of rough rice drying process in fixed and fluidized bed conditions. Journal of Agricultural Sciences and Natural Resources, 14(2). (In Farsi)
Kreith, F. & Raton, B. (1999). Mechanical engineering handbook. CRC Press LLC.
Kunii D. & Levenspiel, O. (1991). Fluidization Engineering. (2nd ed.). Boston: Butterworth-Heinemann.
Mills, D. (2004). Pneumatic conveying design guide. (2nd ed.). Elsevier Butterworth-Heinemann.
Mohsenin, N. N. (1986). Physical properties of plant and animal materials. New York: Gordon and Breach Science Publishers.
Mujumdar, A. S. (2006). Handbook of industrial drying. (3rd ed.). Poland: Taylor and Francis Group, LLC.
Soponronnarit, S., Prachayawarakorn, S. & Sripawatakul, O. (1996). Development of cross-flow fluidized bed paddy dryer. Drying Technology, 14, 2397-2410.
Soponronnarit, S., Yapha, M. & Prachayawarakorn, S. (1995). Cross-flow fluidized bed paddy dryer: prototype and commercialization. Drying Technology, 13, 2207-2216.
Srivastava, A., Goering, C., Rohrbach, R. & Buckmaster, D. (2006). Engineering principles of agricultural machines. (2nd ed.). American Society of Agricultural and Biological Engineers, USA.
Tabatabaeefar, A. & Rafiee, S. H. (2002). Moisture content distribution across a batch-type rough rice dryer. Iranian Journal of Agricultural Sciences, 33(4), 761-775. (In Farsi)
Taechapairoj, C., Dhuchakallaya, I., Soponronnarit, S., Wetchacama, S. & Prachayawarakorn, S. (2003). Superheated steam fluidized bed paddy drying. Journal of Food Engineering, 58, 67-73.
Tirawanichakul, S., Prachayawarakorn, S., Varanyanond, W., Tungtrakul, P. & Soponronnarit, S. (2004). Effect of fluidized bed drying temperature on various quality attributes of paddy. Drying Technology, 22, 1731-1754.
Iranian Journal of Biosystems Engineering
Volume 46, Issue 3 - Serial Number 3
October 2015
Pages 305-313

Files

History

  • Receive Date: 12 January 2015
  • Revise Date: 08 March 2016
  • Accept Date: 21 April 2015

Share

How to cite

Statistics