Vol. 9, No. 2 (May 1996) 1-7   

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E. N. Wami

Department of Chemical/Pertrochemical Engineering
Rivers State University of Science and Technology
Port Harcourt, Nigeria


Abstract    Fluidization of initially segregated binary mixtures has been investigated for particle systems of the same material. This paper reports experiments conducted in 0.055m diameter fluidizes bed for binary mixtures composed of sands whose sizes ranged from 450 to 1450mm. An empirical relationship, Utf = 0.95 UF (dR)0.87, was derived in terms of the minimum fluidization of the smaller particle, UF , and particle diameter ratio, dR , for predicting the velocity at commencement of total fluidization. This expression was found also suitable for estimating the take-over velocity or equidensity binary systems which enables good prediction of mixing behaviour. The corresponding exprrision for pressures drop at the commencement of total fluidization was = exp(1.7 UF(dR)0.13)


Keywords    Fluidization, Fluidized Bed, Minimum Fluidizing Velocity, Take-over Velocity



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