Limits of mass transfer in parallel-plate dialysers

Abstract

The absolute limits of mass transfer across the membrane in a parallel-plate dialyser set by the flow pattern in both channels were determined on the basis of a mathematical model assuming axially dispersed plug flow. The lower limit corresponds to the case of mass transfer under laminar flow conditions. For determination of the upper limit for the same values of the parameters influencing the flow regime (e.g., flow-rate, mean residence time), plug flow and instant restoration of the transverse concentration uniformity, distrubed by the mass-transfer process, were assumed. This case corresponds to infinitely high Peclet numbers and mass-transfer coefficients (Sherwood numbers) in both chann..