Mass transfer performance and correlations for CO₂ absorption into aqueous blended PG/MEA in PTFE membrane contactor

Abstract

BACKGROUND:The method for capturing carbon dioxide (CO 2 ) with amine solution in a hollow fiber membrane contactor has been identified as a potential large-scale application technology for capturing CO 2 from flue gas. The mass transfer performance of CO 2 relies in large extent on the operating conditions, the types of absorbents and the properties of membrane materials. Therefore selecting the appropriate absorbent and studying the effect of operating parameters on the mass transfer performance become of paramount importance. RESULTS:The experimental results showed that the blended potassium glycinate/monoethanolamine solution has better CO 2 absorption performance and higher surface tension than the single monoethanolamine solution under the same conditions. Furthermore, the experimental results illustrated that the CO 2 absorption flux increases as the gas velocity, CO 2 partial pressure and liquid velocity increase, and decreases with the increase of CO 2 loading and membrane contactor length; and the CO 2 removal efficiency increases as the liquid velocity and membrane contactor length increase, and decreases with the increase of CO 2 loading, gas velocity and CO 2 partial pressure. Additionally, new correlations for the prediction of the CO 2 absorption flux J CO2 and the CO 2 removal efficiency CO2 are proposed in this work. The calculated data of CO 2 absorption flux and CO 2 removal efficiency were found to be in satisfactory agreement with experimental results, with absolute average deviation (AAD) lower than 4.42%. CONCLUSION:The correlations for the prediction of J CO2 and CO2 based on the experimental results are of significance for predicting the operating parameters and design of a polytetrafluoroethylene (PTFE) hollow fiber membrane contactor.

Geometry effect on membrane absorption for CO2 capture. Part I: A hybrid modeling approach

“…In the past decades, extensive lab‐scale studies have been reported on membrane absorption (MA) for CO 2 capture using various membrane materials, such as polypropylene (PP) 4 and polytetrafluoroethylene (PTFE), 5–8 and chemical solvents, such as monoethanolamine (MEA), 4 and 4‐diethylamino‐2‐butanol (DEAB) 9 . In addition, some effective approaches are used to reduce the mass transfer resistance of membrane element, such as preparing membranes with notable hydrophobicity (to prevent membrane wetting) 10 and with asymmetric structure (to increase permeability) 11 .…”