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

Abstract

AbstractBACKGROUNDThe method for capturing carbon dioxide (CO2) with amine solution in a hollow fiber membrane contactor has been identified as a potential large‐scale application technology for capturing CO2 from flue gas. The mass transfer performance of CO2 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.RESULTSThe experimental results showed that the blended potassium glycinate/monoethanolamine solution has better CO2 absorption performance and higher surface tension than the single monoethanolamine solution under the same conditions. Furthermore, the experimental results illustrated that the CO2 absorption flux increases as the gas velocity, CO2 partial pressure and liquid velocity increase, and decreases with the increase of CO2 loading and membrane contactor length; and the CO2 removal efficiency increases as the liquid velocity and membrane contactor length increase, and decreases with the increase of CO2 loading, gas velocity and CO2 partial pressure. Additionally, new correlations for the prediction of the CO2 absorption flux JCO2 and the CO2 removal efficiency ηCO2 are proposed in this work. The calculated data of CO2 absorption flux and CO2 removal efficiency were found to be in satisfactory agreement with experimental results, with absolute average deviation (AAD) lower than 4.42%.CONCLUSIONThe correlations for the prediction of JCO2 and ηCO2 based on the experimental results are of significance for predicting the operating parameters and design of a polytetrafluoroethylene (PTFE) hollow fiber membrane contactor. © 2019 Society of Chemical Industry