Fluidized binary mixtures

Chiba S, Nienow AW, Chiba T, Kobayashi H. Fluidized binary mixtures in which the dense component may be flotsam. Powder Technol, 26 1-10, 1980. 

Figure 52 plots the dimensionless subsidence time for the six sets of Group A-A and Group B-A binary mixtures for different fractions of fines, Xp showing that the improvement of fluidizing characteristics by addition of fine particles increases monotonically with increasing percentage of the fines. 

The simplest case for polydisperse systems is a binary mixture of a coarse and a fine size fraction of the same material, each considered to be uniform in size. The generalized fluidization equation for the coarse particles, with subscript 1, is (Kwauk, 1975 Huang et at., 1982)... 

The nonideal nature of G/S fluidization, shown as the bulging curve for zero solids flow in the voidage-velocity plot of Fig. 60, is considered to be caused by gas aggregation at low velocities and solids aggregation at high velocities. Alternately, the G/S system may be visualized to be equivalent to a binary mixture of the aggregated gas bubbles with a volume fraction of (e — 0) on the one hand, and of the aggregated solid particles in the form of clusters with a volume fraction of (1 — e) on the other. At low gas velocities,... 

Cheung, L., Nienow, A. W., and Rowe, P. N., Minimum Fluidization Velocity of a Binary Mixture of Different Sized Particles, (Shorter Commun.) Chem. Eng. Sci. 29, 1301-1303 (1974). 

Gidaspow, D., Huilin, L. and Magner, E. (1996), Kinetic theory of multiphase flow and fluidization validation and extension to binary mixture, 19th Int. Congress on Theoretical and Applied Meek, Kyoto, Japan, pp. 25-31. 

Gidaspow D, Huilin L, Manger E (1996) Kinetic theory of multiphase flow and fluidization Validation and extension to binary mixtures. In Nineteenth Int Cong of Theoretical and Appl Mech, August, Kyoto, Japan, pp 25-31 Grad H (1949) On the kinetic theory of rarified gases. Comm Pure and Appl... 

Figure 7. Comparison of theoretical particle distribution over the fluidized bed height (solid curves) with experimental data in reference [73] elicited while fluidizing binary glass ball mixtures (diameters 0.2 and 0.4 cm) by paraphine oil (v = 0.1 cmVs, u = 7.3 cm/s) and water (v = 0.01 cm /s, u = 25.4 cm/s) (a and b respectively) dashed curves describe partial volume concentrations ( ), and ( )j.

The selective adsorption by NaX of benzene from n-heptane and cyclohexane has also been demonstrated by Tryapina, Seidova, and Agapova. The use of a fluidized bed of NaX for the adsorption of binary mixtures is described by Kvasha et and an extensive review of the adsorption of hydrocarbons from a liquid phase by zeolites had been published by Samoilov and For-minykh. The adsorption properties of Linde 5 A molecular sieve seem to differ markedly from those of NaX. According to Gupta, Kunzru, and Saraf n-pentane, n-hexane, n-heptane, and n-octane are all preferentially adsorbed from mixtures with benzene. The effect of temperature and concentration on the adsorption was studied. 

Lu H, GidaspowD, Manger E Kinetic theory of fluidized binary granular mixtures, Phys Rev E 64 8, 2001. 

The reported minimum fluidization velocities for binary systems in the literature are probably the velocities of either (C/mf)M or (C/n,f)j. For binary systems of small particle size and density difference, these two minimum fluidization velocities may be taken to be similar. Some of the equations proposed for calculating the minimum fluidization velocity of a binary mixture are summarized below. 

Goossens et al. (1971) modified the equation by Wen and Yu (1966b) on the minimum fluidization velocity for single particle size systems by substituting with the mixture particle density, pp, and the mixture particle size, d , of a binary mixture as follows ... 

They found that the Wen and Yu equation as modified could be applied to binary mixtures different in both size and density for the minimum fluidization velocity,... 

Cheung L, Nienow AW, Rowe PN. Minimum fluidization velocity of a binary mixture of different sized paticles. Chem Eng Sci 29 1301-1303, 1974. 

Goossens WRA, Dumont GL, Spaepen GL. Fluidization of binary mixtures in laminar flow region. Chem Eng Prog Symp Ser 67(116) 38-45, 1971. 

Uchida S, Yamada H, Tada I. Minimum fluidization velocity of binary mixtures. J Chinese Inst Chem Eng 14 257-264, 1983. 

Younis HF, Glicksman LR, H5re MR. Measurement and prediction of the hydrodynamics of binary mixtures in a cold model pressurized circulating fluidized bed. In Werther J, ed. Circulating Fluidized Bed Technology VI. Frankfurt DECHEMA, 1999, pp 39 5. 

Jean R-H, Fan L-S. On the criteria of soHds layer inversion in a liquid-solid fluidized bed containing a binary mixture of particles. Chem Eng Sci 41 2811-2821, 1986. 

Because in several applications of three-phase fluidized beds a size distribution is commonly encountered. Fan et al. [75] analyzed the conditions of particle mixing and particle stratification using a binary mixture of solids. Using a 7.62 cm. diameter plexiglass column and two types of binary solid mixtures - 3mm and 4 mm glass particles, and 3 mm and 6 mm glass particles three possible mixing states were observed. These three states... 

Formisani B, Girimonte R, Longo T (2008) The fluidization pattern of densitysegregating binary mixtures. Chem Eng Res Des 86 344-348... 

Lu H, Liu W, Bie R, Yang L, Gidaspow D (2000) Kinetic theory of fluidized binary granular mixtures with unequal granular temperature. Physica A Stat Mech Appl 284 265-276... 

Trujillo, L., Alam, M., and Herrmann, H.J. (2003). Segregation in a fluidized binary granular mixture Competition between bouyancy and geometric forces. Europhys. Lett., 64, 190-196. 

Feng YQ, Yu AB Microdynamic modelling and analysis of the mixing and segregation of binary mixtures of particles in gas fluidization, Chem Eng Sci 62 256—268, 2007. 

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