Modeling of moisture diffusivity, activation energy and specific energy consumption of high moisture corn in a fixed and fluidized bed convective dryer

R. Amiri Chayjan, J. Amiri Parian, M. Esna-Ashari

Abstract


Thin layer drying characteristics of high moisture corn under fixed, semi fluidized and fluidized bed conditions with high initial moisture content (66.82% wb) in a laboratory fluidized bed convective dryer was studied at air temperatures of 50, 65, 80 and 95°C. In order to find a suitable drying curve, seven thin layer-drying models were fitted to the experimental data of moisture ratio. Among the applied mathematical models, Midilli et al. model was the best for drying behavior prediction in corn thin layer drying. This model presented high values for correlation coefficient (R2). Fick´s second law was used to compute moisture diffusivity with some simplifications. Computed values of moisture diffusivity varied at the boundary of 4.87 × 10–11 – 2.90 × 10–10 m2 s–1 and 1.02 × 10–10 – 1.29 × 10–9 m2 s–1 during the first and second drying falling-rate, respectively. Values of effective moisture diffusivity for corn were also increased as input air temperature was increased. Value of activation energy varied from a minimum of 18.57 to a maximum of 50.74 kJ mol–1 from 50 to 95°C with drying conditions of fixed to fluidized bed. Specific energy consumption (SEC) for thin-drying of high moisture corn was found to be in the range of 0.33 × 106 – 1.52 × 106 kJ kg–1 from 50 to 95°C with drying condition of fluidized and fixed bed, respectively. Increase in air temperature in each air velocity caused decrease in SEC value. These corn properties would be necessary to design the best dryer system and to determine the best point of drying process.


Keywords


drying; maize; Midilli et al. model; semi fluidized

Full Text:

PDF

References


Aghbashlo M., Kianmehr M.H., Samimiakhijahani H., 2008. Influence of drying conditions on the effective moisture diffusivity, energy of activation and energy consumption during the thin-layer drying of beriberi fruit (Berberidaceae). Energy Conv Manage 49, 2865-2871. http://dx.doi.org/10.1016/j.enconman.2008.03.009

Aghbashlo M., Kianmehr M.H., Khani S., Ghasemi M., 2009. Mathematical modeling of thin-layer drying of carrot. Int Agrophysics 23, 313-317.

Akpinar E.K., Bicer Y., 2005. Modeling of the drying of eggplants in thin layer. Int J Food Sci Technol 40, 273-281. http://dx.doi.org/10.1111/j.1365-2621.2004.00886.x

Akpinar E., Midilli A., Bicer Y., 2003. Single layer drying behavior of potato slices in a convective cyclone and mathematical modeling. Energy Conv Manage 44, 1689-1705. http://dx.doi.org/10.1016/S0196-8904(02)00171-1

Arumuganathan T., Manikantan M.R., Rai R.D., Anandakumar S., Khare V., 2009. Mathematical modeling of drying kinetics of milky mushroom in a fluidized bed dryer. Int Agrophysics 23, 1-7.

Asae, 2007. ASAE Standard S352.2: moisture measurement-unground grain and seeds, 54th ed. ST Joseph, MI, USA.

Babalis S.J., Belessiotis V.G., 2004. Influence of drying conditions on the drying constants and moisture diffusivity during the thin-layer drying of figs. J Food Eng 65, 449-58. http://dx.doi.org/10.1016/j.jfoodeng.2004.02.005

Brooker D.B., Bakker-Arkema F.W., Hall C.W., 1992. Drying and storage of grains and oilseeds. Van Nostrand Reinold. 443 pp.

Chhinnman M.S., 1984. Evaluation of selected mathematical models for describing thin layer drying of in-shell pecans. T ASAE 27, 610-615.

Crank J., 1975. Mathematics of diffusions. Oxford University Press, London. 414 pp.

Demir V., Gunhan T., Yagcioglu A. K ., Degirmencioglu A., 2004. Mathematical modelling and the determination of some quality parameters of airdried bay leaves. Biosyst Eng 88, 325-335. http://dx.doi.org/10.1016/j.biosystemseng.2004.04.005

Demirel M., Turhan M., 2003. Air drying behavior of dwarf cavendish and gross michel banana slices. J Food Eng 59, 1-11. http://dx.doi.org/10.1016/S0260-8774(02)00423-5

Di Matteo M., Cinquanta L., Galiero G., Crescitelli S., 2000. Effet of novel physical pre-treatment process on the drying kinetics of seedless grapes. J Food Eng 46, 83-89. http://dx.doi.org/10.1016/S0260-8774(00)00071-6

Doymaz I., 2004. Effect of pre-treatments using potassium metabisulphite and alkaline ethyl oleate on the drying kinetics of apricots. Biosyst Eng 89, 281-287. http://dx.doi.org/10.1016/j.biosystemseng.2004.07.009

Doymaz I., Pala M., 2002. The effects of dipping pretreatments on air-drying rates of the seedless grapes. J Food Eng 52, 413-417. http://dx.doi.org/10.1016/S0260-8774(01)00133-9

Erenturk S., Erenturk K., 2007. Comparison of genetic algorithm and neural network approaches for the drying process of carrot. J Food Eng 78, 905-912. http://dx.doi.org/10.1016/j.jfoodeng.2005.11.031

Erenturk S., Gulaboglu M.S., Gultekin S., 2004. The thin layer drying characteristics of rosehip. Biosyst Eng 89, 159-166. http://dx.doi.org/10.1016/j.biosystemseng.2004.06.002

Faostat, 2008. World maize (corn) production. Available in: http://www.geohive.com/charts/ag_maize.aspx.

Foster G.H., Peart R.M., Baker K.D., 1980. Drying grain with heat from solar energy and crop residue. ASAE Publications 1, 137-141.

Goyal R.K., Kingsly A.R.P., Manikantan M.R., Ilyas S.M., 2007. Mathematical modeling of thin layer drying kinetics of plum in a tunnel dryer. J Food Eng 79, 176-180. http://dx.doi.org/10.1016/j.jfoodeng.2006.01.041

Henderson S.M., 1974. Progress in developing the thin layer drying equation. T ASAE 17, 1167-1172.

Khoshtaghaza M.H., Sadeghi M., Amiri Chayjan R., 2007. Study of rough rice drying process in fixed and fluidized bed conditions. J Agric Sci Natural Res 14(2), 127-137.

Kingsly A.R.P., Goyal R.K., Manikantan M.R., Ilyas S.M., 2007. Effects of pretreatments and drying air temperature on drying behaviour of peach slice. Int J Food Sci Technol 42, 65-69. http://dx.doi.org/10.1111/j.1365-2621.2006.01210.x

Kunii D., Levenspiel O., 1991. Fluidisation engineering. Butterworth-Heinemann. 491 pp.

Li H., Morey R.V., 1984. Thin layer drying of yellow dent corn. T ASAE 27(2), 581-585.

Liu Q., Bakker-Arkema F.W., 1997. Stochastic modelling of grain drying: model development. J Agric Eng Res 66, 275-280. http://dx.doi.org/10.1006/jaer.1996.0145

López A., Iguaz A., Esnoz A., Vireda P., 2000. Thinlayer drying behavior of vegetable waste from wholesale market. Drying Technol 18, 995-1006. http://dx.doi.org/10.1080/07373930008917749

Madamba P.S., Driscoll R.H., Buckle K.A., 1996. The thin layer drying characteristic of garlic slices. J Food Eng 29, 81-88. http://dx.doi.org/10.1016/0260-8774(95)00062-3

Midilli A., Kucuk H., Yapar Z., 2002. A new model for single-layer drying. Drying Technol 20(7), 1503-1513. http://dx.doi.org/10.1081/DRT-120005864

Ozdemir M., Devres Y., 1999. The thin layer drying characteristics of hazelnuts during roasting. J Food Eng 42, 225-233. http://dx.doi.org/10.1016/S0260-8774(99)00126-0

Pahlavanzadeh H., Basiri A., Zarrabi M., 2001. Determination of parameters and pretreatment solution for grape drying. Drying Technol 19, 217-226. http://dx.doi.org/10.1081/DRT-100001363

Pala M., Mahmutoglu T., Saygi B., 1996. Effects of pretreatments on the quality of open-air and solar dried products. Food 40, 137-141.

Pathare P.B., Sharma G.P., 2006. Effective moisture diffusivity of onion slices undergoing infrared convective drying. Biosyst Eng 93, 285-291. http://dx.doi.org/10.1016/j.biosystemseng.2005.12.010

Piga A., Pinna I., Ozer K.B., Agabbio M., Aksoy U., 2004. Hot air dehydration of figs (Ficus carica L.): drying kinetics and quality loss. Int J Food Sci Technol 39, 793- 99. http://dx.doi.org/10.1111/j.1365-2621.2004.00845.x

Ramesh M.N., Wolf W., Tevini D., Jung G., 2001. Influence of processing parameters on the drying of spice paprika. J Food Eng 49, 63-72. http://dx.doi.org/10.1016/S0260-8774(00)00185-0

Rapusas R.S., Driscoll R.H., 1995. The thin layer drying characteristics of white onion slices. Drying Technol 13, 1905-1931. http://dx.doi.org/10.1080/07373939508917056

Sarsavadia P.N., Sawhney R.L., Pangavhane D.R., Singh S.P., 1999. Drying behaviour of brined onion slices. J Food Eng 40, 219-226. http://dx.doi.org/10.1016/S0260-8774(99)00058-8

Soponronnarit S., Pongtornkulpanich A., Prachayawarakorn S., 1997. Drying characteristics of corn in fluidized bed dryer. Drying Technol 15(5), 1603-1615. http://dx.doi.org/10.1080/07373939708917311

Suárez C., Loncin M., Chirife J.A., 1984. Preliminary study on the effect of ethyl oleat dipping treatment on drying rate of grain corn. J Food Eng 49, 236-238.

Tarigan E., Prateepchaikul G., Yamseangsung R., Sirichote A., Tekasakul P., 2006. Drying characteristics of unshelled kernels of candle nuts. J Food Eng 79, 828-833. http://dx.doi.org/10.1016/j.jfoodeng.2006.02.048

Togrul I.T., Pehlivan D., 2002. Mathematical modelling of solar drying of apricots in thin layers. J Food Eng 55, 209-216. http://dx.doi.org/10.1016/S0260-8774(02)00065-1

Wang C.Y., Singh R.P., 1978. Use of variable equilibrium moisture content in modelling rice drying. ASAE Paper No. 78-6505. ASAE Press, St Joseph, MI, USA.

Yaldiz O., Ertekin C., Uzun H.I., 2001. Mathematical modelling of thin layer solar drying of sultana grapes. Energy 26, 457-465. http://dx.doi.org/10.1016/S0360-5442(01)00018-4

Zhang Q., Litchfield J.B., 1991. An optimization of intermittent corn drying in a laboratory scale thin layer dryer. Drying Technol 9, 383-395. http://dx.doi.org/10.1080/07373939108916672

Zhang Q., Yang S.X., Mittal G.S., Yi S., 2002. Prediction of performance indices and optimal parameters of rough rice drying using neural network. Biosyst Eng 83(3), 281-290.




DOI: 10.5424/sjar/20110901-077-10