Mass transfer enhancement of hollow fiber membrane deoxygenation by Dean vortices

Abstract

This paper reports a modeling and experimental study of the mass transfer enhancement of water deoxygenation by using a helical hollow fiber membrane (HHFM) to enable Dean vortices. Experiments demonstrated that the HHFM deoxygenating rate was doubled compared with straight hollow fiber deoxygenation. A new model to describe the HHFM deoxygenation mass transfer was derived combining the helical coordinate system mass continuity equation on the lumen side and a modified dusty gas model for the mutual gaseous diffusion in the porous membrane. The model simulation showed that Dean vortices induce transverse fluid disturbance in the fiber, which significantly promotes lumen side mass transfer. The key parameters influencing the strength of Dean vortices are the Reynolds number of the lumen side and the curvature of HHFM. Operating and membrane structure parameters were optimized for HHFM deoxygenation design. The new model could be employed to describe quantitatively the mass transfer behavior of all types of HHFM gas-phase separation processes.