Mixing and Segregation Characteristics of Binary Granular Material in Tapered Fluidized Bed: A CFD Study

DOI: 10.4236/eng.2012.44029   PDF   HTML     5,167 Downloads   8,510 Views   Citations


The particle flow pattern, mixing and granule segregation in a tapered fluidized bed have been studied along with the hydrodynamics. At first the bed of varying total mass and granule fractions is fluidized then the bed is defluidized to freeze the composition, the bed is sectioned to layers and the composition in each layer is determined by sieving. Materials used in the present study are dolomite and glass beads with different B.S.S Sizes. A series of unsteady, three fluid CFD simulations were performed using FLUENTTM 6.2. Simulation parameters viz. solution technique, grid, maximum packing fraction and operating conditions like gas velocity were investigated for relative effects on particle mixing and segregation. Good arrangement of solid volume fraction profile was obtained between the experimental results and simulation results for regular particles.

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H. Sutar and C. Das, "Mixing and Segregation Characteristics of Binary Granular Material in Tapered Fluidized Bed: A CFD Study," Engineering, Vol. 4 No. 4, 2012, pp. 215-227. doi: 10.4236/eng.2012.44029.

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The authors declare no conflicts of interest.


[1] Y. F. Shi, Y. S. Yu and L. T. Fan, “Incipient Fluidization Con-dition for a Tapered Fluidized Bed,” Industrial & Engineering Chemistry Fundamental, Vol. 23, No. 4, 1984, pp. 484-489. doi:10.1021/i100016a018
[2] Y. Peng and L. T. Fan, “Hy-drodynamic Characteristics of Fluidization in Liquid-Solid Tapered Beds,” Chemical Engineering Science, Vol. 52, No. 14, 1997, pp. 2277- 2290. doi:10.1016/S0009-2509(97)00061-4
[3] F. Depypere, J. G. Pieters and K. Dewettinck, “Expanded Bed Height Determina-tion in a Tapered Fluidized Bed Reactor,” Journal of Food Engineering Vol. 67, 2005, pp. 353-359. doi:10.1016/j.jfoodeng.2004.04.039
[4] H. G. Kim, I. O. Lee, U. C. Chung and Y. H. Kim, “Fluidization Characteristics of Iron Ore Fines of Wide Size Distribution in a Cold Tapered Gas-Solid Fluidized Bed,” ISIJ International, Vol. 40, No. 1, 2000, pp. 16-22. doi:10.2355/isijinternational.40.16
[5] S. H. Schaafsma, T. Marx and A. C. Hoffmann, “Investigation of the Particle Flow Pattern and Segregation in Tapered Fluidized Bed Granulators,” Chemical Engineering Science, Vol. 61, No. 14, 2006, pp. 4467-4475. doi:10.1016/j.ces.2006.01.040
[6] C. D. Scott and C. W. Hancher, “Use of Tapered Fluidized Bed as a Continuous Bio-reactor,” Biotechnology and Bioengineering, Vol. 18, No. 10, 1976, pp. 1393-1403. doi:10.1002/bit.260181006
[7] S. P. Babu, S. Leipsiger, B. S. Lee and S. A. Wiel, “Solids Mixing in Batch Operated Tapered Bed and Non-Tapered Gas Fluidized Beds,” Fluidized Bed Fundamentals and Application, AIChE Symposium Series, Vol. 69, 1973, pp. 49-57.
[8] H. Toyohara and Y. Kawamura, “Core Type Segregation in a Tapered Fluidized Bed of Binary Particle Mixtures,” Kagaku Kogaku Ronbunshu, Vol. 17, No. 1, 1992, pp. 172-178. doi:10.1252/kakoronbunshu.17.172
[9] S. K. Agarwal and G. K. Roy, “Packed Bed Pressure Drop and Incipient Fluidization Condition in a Conical Bed of Spherical Particles—A Mathematical Model,” Indian Chemical Engineer, Vol. 30, No. 3, 1998, p. 3.
[10] T. Maruyama and T. Koyanagi, “Slugging Fluidized Bed in Tapered Vessels,” Chemical Engi-neering Journal, Vol. 52, 1993, p. 9.
[11] G. Kwant, W. prins and W. P. M. Van swaaij, “Particle Mixing and Separation in a Binary Solids Floating Fluidized Bed,” Powder Technology, Vol. 82, No. 3, 1994, pp. 279-291. doi:10.1016/0032-5910(94)02937-J
[12] S. Chiba, A. W. Nie-now, T. Chiba and H. Kobayashi, “Fluidized Binary Mixtures in Which the Denser Component May Be Flotsam,” Powder Technology, Vol. 26, No. 1, 1980, pp. 1-10. doi:10.1016/0032-5910(80)85001-7
[13] P. N. Rowe and A. W. Nienow, “Minimum Fluidization Velocity of Multi-Component Particle Mixtures,” Chemical Engineering Science, Vol. 30, No. 11, 1975, pp. 1365-1369. doi:10.1016/0009-2509(75)85066-4
[14] L. G. Gibilaro and P. N. Rowe, “A Model for Segregating Fluidized Bed,” Chemical Engineering Science, Vol. 29, No. 6, 1974, pp. 1403-1412. doi:10.1016/0009-2509(74)80164-8
[15] J. C. Williams, “Mixing and Segregation in Powders,” In: M. Rhodes, Ed., Principles of Powder Technology, Wiley, 1990, Lon-don.
[16] G. P. Hartholt, A. C. Hoffmann and L. P. B. M. Janssen, “Visual Observation of Individual Particle Behavior in Gas and Liquid Fluidized Beds,” Powder Technology, Vol. 88, No. 3, 1996, pp. 341-345. doi:10.1016/S0032-5910(96)03139-7
[17] P. N. Rowe, A. W. Nienow and A. J. Agbim, “A Preliminary Quantitative Study of Particle Segregation in a Gas Fluidized Beds-Binary Systems of Near Spherical Particles,” Transactions of the Institution of Chemical Engineers, Vol. 50, 1972, pp. 324-333.
[18] H. Tanimoto, S. Chiba, T. Chiba and H. Kobayashi, “Jetsam De-scent Induced by a Single Bubble Passage in Three Dimen-sional Gas Fluidized Beds,” Journal of Chemical Engineering of Japan, Vol. 14, No. 4, 1981, pp. 273-276. doi:10.1252/jcej.14.273
[19] J. C. Bosma and A. C. Hoffmann, “On the Capacity of Continuous Powder Classification in a Gas Fluidized Bed with Horizontal Baffles,” Powder Technology, Vol. 134, No. 1-2, 2003, pp. 1-15. doi:10.1016/S0032-5910(03)00097-4
[20] A. C. Hoffmann and E. J. Romp, “Segregation in Fluidized Powder of a Con-tinuous Size Distribution,” Powder Technology, Vol. 66, No. 2, 1991, pp. 119-126. doi:10.1016/0032-5910(91)80093-X
[21] R. Clift, J. P. K.Seville, C. Moore and C. Chavarie, “Comments on Buoyancy in Fluidized Beds,” Chemical Engineering Science, Vol. 42, No. 1, 1987, pp. 1991-1996. doi:10.1016/0009-2509(87)80228-2
[22] K. Ridgway, “Ta-pered Fluidized Bed—A New Processing Tool,” Chemical and Process Engineering, Vol. 46, 1965, pp. 317-326.
[23] H. To-yohara and Y. Kawamura, “Fluidization of Tapered Bed of Binary Particle Mixture,” International Chemical Engineering, Vol. 32, No. 1, 1991, p. 164.
[24] T. M. Gernon, M. A. Gilbertson and R. S. J. Sparks, “Particle Segregation in Tapered Fluidized Beds,” The 13th International Conference on Fluidi-zation—New Paradigm in Fluidization Engineering, Vol. RP6, 2010, Article 91.

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