The effect of breakup and coalescence of bubbles on mass transfer in a fluidized bed (Q1072883)

The mechanics of interpenetrating and mutually reacting continua is used to study a plane problem, modelling the motion of the solid and liquid phase and mass transfer to bubbles during their breakup and coalescence. It is assumed that the interphase resistance is described, as in the Davidson model [\textit{J. F. Davidson} and \textit{D. Harrison}, Fluidized particles, Cambridge Univ. Press (1963)], by Darcy's law, with the concentration of solid phase outside the bubbles remaining constant. The phase velocity field and pressure field of the liquid phase are constructed and, the conditions for the existence and form of the cloud circulation of the fluid are determined near two intersecting or mutually touching circular bubbles. A solution of the problem of diffusive material flow to the cloud surface is given and the mass transfer coefficient between the bubbles and the continuous phase of the fluidized bed is determined. The results obtained enable the influence of the breakup and coalescence of the bubbles and the presence of a rigid wall near the bubble and of bubble deformation on the intensity of the mass transfer process, to be assessed.