Behaviors of the bubble, cloud and emulsion phases in a fluidized bed

Régis Andreux (1) , Jamal Chaouki (2)

1 LGC - Laboratoire de Génie Chimique
2 EPM - École Polytechnique de Montréal

An intrusive bioptical probe provides radial profiles of the PDF (Probability Density Function) of the bubble, the cloud and the emulsion phases behaviors in a fluidized bed of Geldart-A particles. The fluidizing velocity ranges between 0.20 m/s and 0.80 m/s. The bed porosity, the overall averaged bubble chords and velocities are well-predicted by correlations of the literature. The cloud thickness is closely related to the bubble chord. The amount of gas traveling through the bubble phase never exceeds 15-20 % of the total gas flow rate. The averaged porosity of the bubble, the cloud and the emulsion phases is of 88-92 %, 65-70 % and 50-55 %, respectively. The reduced bubble porosity distribution obeys a constant normal law over the fluidizing velocity range. Each distribution of the reduced bubble chord and velocity, and of the reduced cloud thickness obey a constant log normal law over the fluidizing velocity range.

Mots clés: Fluidization; Experiments; Particle; Optical probe; Bubble; Cloud; Emulsion

Domaines: Génie chimique

Régis Andreux, Jamal Chaouki. Behaviors of the bubble, cloud and emulsion phases in a fluidized bed. AIChE Journal, 2008, vol. 54 n° 2., pp. 406 -414 available on : http://oatao.univ-toulouse.fr/104/1/andreux_104.pdf. ⟨10.1002/aic.11390⟩. ⟨hal-00467482⟩