A GAUSSIAN-CONVECTION MODEL FOR SOLID DISPERSION IN SLURRY BUBBLE-COLUMNS

The use of a diffusive-type model to represent the behaviour of solid particles in a slurry bubble column has been questioned. In agreement with the observation of Levenspiel and Fitzgerald, a sedimentation-convection model for solid behaviour in slurry bubble columns is presented. With this model, the analytical solution for axial solid concentration for monodispersed particles in a slurry bubble column at steady state for the continuous flow of slurry and gas is derived to be: C(s) = U1C(s)f/(U1 +/- V(p)). The use of the model together with the correlations of Ramachandran and Chaudhari for particle settling velocity in slurry bubble columns has been found to well predict the solid hold-up in the monodispersed solid systems of Bhaga and Weber and also in the polydispersed solid systems operated in both cocurrent and countercurrent mode.