Article

Modeling and calculation of temperature-concentration polarisation in the membrane distillation process (MD)

Department of Chemical Engineering, Mendeleev Institute, Miusskaja Square 9, Moscow A-190 125190 Russia
Desalination 01/1993; DOI: 10.1016/0011-9164(93)80107-X

ABSTRACT A model for a membrane distillation process in a plate-and-frame unit has been developed. It is based on a mass and energy balance equation for hydrodynamic, temperature and concentration boundary layers. The model takes into account energy interdependence between flow in feed and in permeate channels. A model taking into consideration temperature-concentration polarisation (TCP) predicts temperature and concentration values at the membrane surface. The model consists of an analytical equation and permits simulation or analysis of the influence of various factors to permeate flux.

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