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Microwave Drying of Sawdust for Pellet Production: Kinetic Study under Batch Mode

  • Bhattarai, Sujala (Department of Biosystems Engineering, Kangwon National University) ;
  • Oh, Jae-Heun (Forest Practice Research Center, Korea Forest Research Institute) ;
  • Choi, Yun Sung (Department of Biosystems Engineering, Kangwon National University) ;
  • Oh, Kwang Cheol (Department of Biosystems Engineering, Kangwon National University) ;
  • Euh, Seung Hee (Department of Biosystems Engineering, Kangwon National University) ;
  • Kim, Dae Hyun (Department of Biosystems Engineering, Kangwon National University)
  • Received : 2012.10.03
  • Accepted : 2012.12.23
  • Published : 2012.12.31

Abstract

Purpose: Drying characteristics of sawdust was studied under batch mode using lab scale microwave dryer. The objective of this study was to investigate the effect of material load and microwave output power on drying characteristics of sawdust. Methods: Material load and microwave output power were varied from 23 to 186 g and 530 to 370 W respectively. Different kinetic models were tested to fit the drying rates of sawdust. Similarly, the activation energy was calculated by employing the Arrhenius equation. Results: The drying efficiency increased considerably, whereas the specific energy consumption significantly decreased with increase in material load and microwave output power. The cumulative energy efficiency increased by 9%, and the specific energy consumption decreased by 8% when the material load was increased from 23 to 186 g. The effective diffusivity increased with decrease in material load and increase in microwave output power. The previously published model gave the best fit for data points with $R^2$ and RMSE values of 0.999 and 0.01, respectively. Conclusions: The data obtained from this study could be used as a basis for modeling of large scale industrial microwave dryers for the pellet production.

Keywords

References

  1. Araszkiewicz, M., A. Koziol, A. Oskwarek and M. Lupinski. 2004. Microwave drying of porous materials. Drying Technology 22(10):2331-2341. https://doi.org/10.1081/DRT-200040014
  2. Bushbeck, E., E. Keiner and J. Klinner. 1967. Trocknungsphysikalische and warmetechnische Untersuchung zur Trocknung von Pfefferminze. [Physical and thermal properties effecting drying characteristics of peppermint.] Archiv fur Landtechnik 2:163-200.
  3. Chen, D., Y. Zheng and X. Zhu. 2012. Determination of effective moisture diffusivity and drying kinetics of popular sawdust by thermo gravimetric analysis under isothermal condition. Bioresource Technology 107: 451-455. https://doi.org/10.1016/j.biortech.2011.12.032
  4. Crank, J. 1975. The mathematics of Diffusion, 2nd Ed., Clarendon Press, Oxford, UK.
  5. Dadali, G., E. Demirhan and B. Ozbek. 2007. Microwave heat treatment of spinach, Drying kinetics and effective moisture diffusivity. Drying Technology 25(10):1703- 1712. https://doi.org/10.1080/07373930701590954
  6. FAO, 1990. Energy conservation in the mechanical forest industries.
  7. Filbakk, T., G. Skjevrak, O. Dibdiakova and J. Jirjis. 2011. The influence of storage and drying methods for Scots pine raw material on mechanical pellet properties and production parameters. Fuel Processing Technology 92:871-878. https://doi.org/10.1016/j.fuproc.2010.12.001
  8. Gomez, K.A. and A. A. Gomez. 1984. Statistical procedures for agricultural research. John Wiley and Sons, Inc., NY, USA.
  9. Henderson, S.M. and S. Pabis. 1961. Grain drying technology: 1. Temperature effect on drying coefficient. Journal of Agricultural Engineering Research 6(3): 169-74.
  10. Hayes, G. D. 1987. Food Engineering Data Handbook. Longman Scientific and Technical, England.
  11. Jia, D. H. and M.T. Afzal. 2007. Modeling of moisture diffusion in microwave drying of hardwood. Drying Technology 25(1):449-454. https://doi.org/10.1080/07373930601183843
  12. Kaya, A. and O. Aydin. 2009. An experimental study on drying kinetics of some herbal leaves. Energy Conversion and Management 50:118-24. https://doi.org/10.1016/j.enconman.2008.08.024
  13. Khraisheh, M., A. M. Cooper and T. J. R. Magee. 1997. Microwave and air drying I. Fundamental consideration and assumptions for the simplified thermal calculations of volumetric power absorption. Journal of Food Engineering 33:207-219. https://doi.org/10.1016/S0260-8774(97)00050-2
  14. Kim, D.H., B.M. Jenkins, T.R. Rumsey, M.W. Yore and N.J. Kim. 2007. Simulation and model validation of a horizontal shallow basin solar concentrator. Solar Energy 81:463-475. https://doi.org/10.1016/j.solener.2006.08.007
  15. Little, T.M. and F. J. Hills. 1978. Agricultural experimentation: design and analysis. John Wiley and Sons, Inc., NY, USA.
  16. Lix, J., B. G. Zang and W.J. Li. 2008. Microwave-vaccum drying of wood model formulation and verification. Drying Technology 26(10):1382-1387. https://doi.org/10.1080/07373930802333551
  17. Lu, L., J. Tang and L. Liang. 1998. Moisture Distribution in Spherical foods in Microwave Drying, Drying Technology 16 (3-5):503-524. https://doi.org/10.1080/07373939808917421
  18. Maskan, M. 2000. Microwave/air and microwave finish drying of banana. Journal of Food Engineering 44:71-78. https://doi.org/10.1016/S0260-8774(99)00167-3
  19. Metaxas, A.C. and R.J. Meredith, 1993. Industrial Microwave Heating. Peter Peregrinus, Ltd. London, UK. pp. 375.
  20. Midilli, A., H. Kucuk and Z. Yapar. 2002. A new model for single layer drying. Drying Techonology 20(7):1503- 1513. https://doi.org/10.1081/DRT-120005864
  21. Mousa, N. and M. Farid. 2002. Microwave vacuum drying of banana slices. Drying Technology 20(10):2055-2066. https://doi.org/10.1081/DRT-120015584
  22. Muller, J., G. Reisinger and W. Mühlbauer. 1989. Trocknung von Heil-und Gewürzpflanzen mit Solarenergie im Folienge wächshause [Drying of medicinal and aromatic plants in a greenhouse solar dryer]. Landtechnik, 2:58-65.
  23. O'Callaghan. J.R., D. J. Menzies and P.H. Bailey. 1971. Digital simulation of agricultural dryer performance. Journal of Agricultural Engineering Research 16:223- 244. https://doi.org/10.1016/S0021-8634(71)80016-1
  24. Olsson, M. 2001. Trapellets som smaskaligt biobransle. Report Chalmers Univerisity of Technology, Goteborg and STEM.
  25. Ozbek, B. and G. Dadali. 2007. Thin layer drying characteristic and modeling of mint leaves undergoing microwave treatment. Journal of Food Engineering 83:541-9. https://doi.org/10.1016/j.jfoodeng.2007.04.004
  26. Page, G. 1949. Factors influencing the maximum rates of air drying shelled corn in thin layers. MSc thesis, Purdue University, Indiana, USA.
  27. Rodrigues, R., J. Lombrana, M. Kamel and C. Elvira. 2005. Kinetics and quality study of mushroom drying under microwave and vacuum. Drying Technology 23 (9-11): 2197-213. https://doi.org/10.1080/07373930500212685
  28. Schiffmann, R.F. 1997. Principles of industrial microwave and RF heating. In Microwaves: Theory and Application in Materials Processing IV (D.E. Clark, W.H. Sutton and D.A. Lewis, eds.) pp. 41-60, The American Ceramic Society, Westerville, OH.
  29. Soysal, Y. and S. Oztekin. 2001. Technical and economic performance of tray dryer for medicinal and aromatic plants. Journal of Agricultural Engineering Research 79(1):73-79. https://doi.org/10.1006/jaer.2000.0668
  30. Soysal, Y., S. Oztekin and O. Eren. 2006. Microwave drying of parsley: Modelling, Kinetics, and Energy Aspects. Biosystems Engineering 93(4):103-413.
  31. Taira, H. and T. Matsui. 2008. High capacity microwave drying of monolithic refractories in Nippon steel corporation, Drying Technology 28(2):143-149.
  32. Wang, C.Y. and R.P. Sing. 1978. A single layer drying equation for rough rice. ASAE Paper No 78-3001, ASAE, St. Joseph, MI.
  33. White, J.R. 1973. Why materials heat. Trans. IMPI 1, paper No 4, 40-65.
  34. Yagcioglu A., A. Degirmencioglu and F. Cagatay. 1999. Drying characteristics of laurel leaves under different drying conditions. Proceedings of the 7th international Congress on Agricultural Mechanization and Energy in Agriculture, pp 565-569. Adana, Turkey, 26-27 May.
  35. Yongsawatdigul, J. and S. Gunasekaran. 1996. Microwavevacuum drying of cranberries:- Part I: energy use and efficiency. J. Food process. Pres. 20:121-143. https://doi.org/10.1111/j.1745-4549.1996.tb00850.x
  36. Yu, L., L. Ying, Z. Li-bo, P. Jin-hui and L. Chang-long. 2011. Microwave drying characteristics and kinetics of ilmenite, Transactions of nonferrous metals society of China, 202-207.
  37. Zang, M., J. Tang, As. Mujumdar and S.S. Wang. 2006. Trends in microwave related drying of fruits and vegetables. Trends in Food Science and Technology 17:524-34. https://doi.org/10.1016/j.tifs.2006.04.011

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