Experimental Measurement and Modeling Prediction of Mass Transfer in a Hollow Fiber Membrane Contactor Using Tertiary Amine Solutions for CO2 Absorption

A poly(tetrafluoroethylene) hollow-fiber membrane contactor was used for CO2 absorption in tertiary amine solutions. Several influential factors were studied including the flow rate, concentration, temperature, CO2 loading of the absorbent and CO2 partial pressure, and velocity of mixed gas. Based on the finite elemental analysis method, a two-dimensional steady-state mathematical model was established using COMSOL Multiphysics simulation software to calculate CO2 mass transfer flux (JCO2) and CO2 concentration distribution in the hollow-fiber membrane contactor under nonwetting and partial-wetting conditions. Results show that the mass transfer was severely reduced in the partially wet membrane, and the predicted JCO2 under 15% membrane wetting agreed well with the experimental value. In addition, a dimensionless equation was developed to predict the liquid phase, gas phase, and membrane phase mass transfer coefficients and JCO2. The calculated JCO2 values are in good agreement with the experimental values with an average absolute relative deviation (AARD) of 9.4%.