Minimum Fluidization Velocities of Binary-Solid Mixtures: Model Comparison

An accurate prediction of the minimum fluidization velocity is a crucial hydrodynamic aspect of the design of fluidized bed reactors. Common approaches for the prediction of the minimum fluidization velocities of binary-solid fluidized beds are first discussed here. The data of our own careful experimental investigation involving a binary-solid pair fluidized with water is presented. The effect of the relative composition of the two solid species comprising the fluidized bed on the bed void fraction at the incipient fluidization condition is reported and its influence on the minimum fluidization velocity is discussed. In this connection, the capability of packing models to predict the bed void fraction is also examined.

Authors:

• Mohammad Asif

Keywords:

• Bed void fraction
• Binary solid mixture
• Minimumfluidization velocity
• Packing models

References:

[1] N. Epstein, "Applications of Liquid-Solid Fluidization," Int. J. of Chem.
Reactor Eng., vol. 1, R1, 2003.
[2] K. Adham, "Classify particle using fluidized beds," Chem. Eng.
Prog., vol. 9, pp. 55-57, 2001.
[3] X. Hu and J.M. Calo, "Plastic particle separation via liquid-fluidized
bed classification," A.I.Ch.E. J., vol. 52, pp. 1333-1342, 2005.
[4] I. Narvaez, I., A. Orio, M.P. Aznar and J. Corella, Ind. Eng. Chem. Res.,
vol. 35, pp. 2110-2120, 1996.
[5] A. Olivares, M.P. Aznar, M.A. Caballero, J. Gil, E. Frances and J.
Corella, Ind. Eng. Chem. Res., vol. 36, pp. 5220-5226, 1997.
[6] F. Berruti, A.G. Liden and D.S. Scott , Chem Eng. Sci., vol. 43, pp. 739-
748, 1988.
[7] A. Ajbar, K. Alhumaizi, A.A. Ibrahim and M. Asif, "Hydrodynamics of gas
fluidized beds with mixture of group D and B particles," Can. J. Chem.
Eng, vol. 80, pp. 281-288, 2002..
[8] A. Ajbar, K. Alhumaizi and M. Asif, "Improvement of the fluidizability of
cohesive powders through mixing with small proportions of Group A
particles," Can. J. Chem. Eng., vol. 83, pp. 930-943, 2005
[9] S. Ergun, Chem. Engng. Prog., vol. 48, pp. 88-94, 1952.
[10] B. Formisani, Powder Technol., vol. 66, pp. 259-264, 1991.
[11] Z. Li, N. Kobayashi, A. Nisjimura and M. Hasatani, Chem. Eng.
Comm., vol. 192, pp. 918-932, 2005.
[12] T. Stovall, F. De Larrad and M. Buil, Powder Technol., vol. 48, pp. 1-
12, 1986.
[13] A.B. Yu and N. Standish, Powder Technol., vol. 55, pp. 171-186, 1988.
[14] A.B. Yu and N. Standish, Ind. Eng. Chem. Res., vol. 30, pp. 1372-1385,
1991.
[15] A.B. Yu, R.P. Zou and N. Standish, "Modifying the linear packing
model for predicting the porosity of non-spherical particle mixtures,"
Ind. Eng. Chem. Res., vol. 35, pp. 3730-3741, 1996.
[16] N. Ouchiyama and T. Tanaka, Ind. Eng. Chem. Res., vol. 28, pp. 1530-
1536, 1989.
[17] A.E.R. Westman, "The packing of particles: Empirical equations for
intermediate diameter ratios," J. Am. Ceram. Soc., vol. 19, pp. 127-129,
1936.
[18] A.B. Yu, N.Standish and A.McLean, "Porosity calculation of binary
mixture of nonspherical particles," J. Am. Ceram. Soc., vol. 76, pp.
2813-2816, 1993.
[19] H.J. Finkers and A.C. Hoffmann, "Structural ratio for predicting the
voidage of binary particle mixture," A.I.Ch.E..J., vol. 44, pp. 495-498,
1998.
[20] A.R. Otero and J. Corella, Anales de la RSEFQ, vol. 67, pp. 1207-1219,
1971.
[21] E. Obata, H. Watanbe and N. Endo, J. Chem. Eng. Japan, vol. 15, pp.
23-28, 1982.
[22] J. Rincon, J. Guardiola, A. Romerero and G. Ramos, J. Chem. Eng.
Japan, vol. 27, pp. 177-181, 1994.
[23] M. Asif and A.A. Ibrahim, "Minimum fluidization velocity and
defluidization behavior of binary-solid liquid-fluidized beds,". Powder
Technol., vol. 126, pp. 241-254, 2002.
[24] L. Cheung, A.W. Nienow and Rowe, P.N., Chem. Eng. Sci., vol. 29, pp.
1301-1303, 1973.