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 (Impact Factor: 3.96). 08/1993; 93(1-3):245-258. 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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    • "This phenomenon referred as temperature polarisation [23] [24] [25] [26] has been shown to reduce the flux across membranes. We address these issues by functionalising the outer walls of the CNTs with 3-glycidoxypropyltrimethoxysilane (GPTMS) chains. "
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    Journal of Membrane Science 07/2011; 376(1-2):241-246. DOI:10.1016/j.memsci.2011.04.024 · 4.91 Impact Factor
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    • "The first is the temperature polarization across the membrane [12] [13] [14] [15], the second is the resistance to vapor flow through the membrane due to the presence of trapped air in the pores [16] [17] [18], and the third is a conductive heat loss through the membrane [19] [20] [21] [22]. The majority of previous investigations focused on the effects of either temperature polarization or resistance to vapor flow in the pores on the performance of MD. "
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    Journal of Membrane Science 01/2004; 228(1-228):5-16. DOI:10.1016/j.memsci.2003.09.006 · 4.91 Impact Factor
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    • "In [12], correlations for mass transfer in spacer-filled channels, obtained in [13] [14], are written out in terms of heat transfer, and quantitative considerations on temperature polarization are given, as well as in [15]. Models that make use of assumed velocity profiles for the calculation of temperature profiles along the membrane surface [16] and in the liquid phase [17] are also available. In [18], heat and mass transport equations have been solved using the analytical solution of equations for momentum transport in highly viscous fluids with permeation taken into account. "
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