Modeling spiral-wound membrane modules with applications for gas/vapor permeation

Gas/vapor permeation has become a common method for VOC (volatile organic compound) recovery and CO2 capture. The spiral-wound membrane module, which has high packing density, has been commonly used in gas/vapor permeation. In this study, the model that suits the spiral-wound PDMS (polydimethylsiloxane) membrane is obtained by using an integral transform from an N–S equation (Navier–Stokes) and a mass transfer differential equation. The predicted results indicate that the concentration polarization and spiral-wound membrane structure influence can be neglected. The mass transfer based on the MS–UNIQUAC (MS–U) model is also proposed and compared to that based on the Fick–Henry (F–H) model. The comparison results show that the mass transfer based on the F–H model can only be used in a gas mixture without condensable gas; the MS–U model should be used for a gas mixture that includes condensable gas. The influence of permeate flux and feed-side composition in the spiral-wound membrane at different operation conditions is also investigated using the MS–U model.

► The model that suits for spiral wound membrane based on F–H model is obtained. ► The spiral wound membrane structure and concentration polarization have no effect. ► The model based on MS–U model is obtained and compared with that based on F–H model. ► Different gas mixtures under different operating conditions are predicted by MS–U model.