Counter-current flow of dispersed and continuous phase—I: Discrete polydispersed model

A discrete mathematical model has been proposed of the counter-current gravitational flow of a continuous and a polydispersed phase in vertical column contactors. Allowances have been made for particle entrainment, newly defined back flow of particles in relation to the back flow of the continuous phase, particle dispersion and coalescence. Appropriate solutions enable profiles to be obtained of local hold-up of the dispersed phase as well as those of particle size distribution along the contactor's length. The model with the parameters distributed with respect to particle size has served to derive in turn a lumped parameter modification whose limits of applicability have been shown.