Mass transfer regimes in reactions with a dispersed phase

Abstract

Equations are formulated which determine the movement of phases and the integral interphase mass transfer in isothermal two-phase reactors. Simple models of extraction which are not accompanied by a change of the specific volume of the phases and the dissolution of gas in the countercurrent columns and apparatuses with a horizontal flow of liquid are discussed. Some conclusions obtained differ considerably from the traditional ideas of the theory of solvent extraction. Mass transfer between the dispersion (continuous) medium and the dispersed (disperse) phase in the presence of relative movement of the phases are considered below. Such processes are realized in practice in various bubbling and atomizing devices (extraction or absorption countercurrent columns, some types of scrubbers, plate and other apparatuses with a horizontal flow of the continuous medium, etc.). Of primary interest is the macroscopic description of mass transfer; the quantities characterizing local mixing in the reactor and momentum and mass transfer between the dispersion medium and a single particle (drop or bubble) of the dispersed phase are assumed to be known functions of the macroscopic parameters.