Modeling of CO2 Stripping in a Hollow Fiber Membrane Contactor for CO2 Capture

Membrane stripping is a promising method for carbon dioxide (CO 2 ) desorption with low energy demand. We developed a mathematical model to simulate the CO 2 stripping from the CO 2 -rich monoethanolamine (MEA) solvent in a hollow fiber membrane contactor. The modeling results agreed well with literature experimental results. To improve the understanding and facilitate the optimization of the membrane based CO 2 stripping process, we investigated the effects of different operating variables including liquid flow velocity, sweeping gas flow rate, regeneration pressure, and temperature on CO 2 desorption performance. The effects of membrane’s length and diameter of membrane fiber on CO 2 desorption were also studied. Results showed that increasing membrane’s length will improve CO 2 stripping performance, but not infinitely, because of the thermodynamic limitation of absorbent, and shorter membrane module is preferred for thinner membrane. Membranes with a smaller diameter favor CO 2 desorption. To predict the influence of membrane wetting on CO 2 stripping performance, the change of CO 2 lean loading with the wetting ratio was investigated. Membrane wetting significantly deteriorates CO 2 membrane desorption performance, with CO 2 lean loading increasing suddenly once the membrane is wetted.