Modeling of CO2 absorption into 4-diethylamino-2-butanol solution in a membrane contactor under wetting or non-wetting conditions

Abstract

In this work, 4-diethylamino-2-butanol (DEAB) as a new type of alkanolamine solvent is used for CO2 capture in a hollow fiber membrane contactor (HFMC). A model describing the gas and liquid reactions and transport inside the membrane contactor under the wetting or non-wetting conditions was built. The countercurrent flow of natural gas and solvent was considered in the model. To investigate the influence of solvent type on decarburization efficiency, DEAB was used and compared with other common solvents such as potassium carbonate (K2CO3), triethylamine (TEA) and diethanolamine (DEA). Under the same operating conditions, the impact of parameters such as humidity, gas flow rate, liquid concentration, membrane length on the decarburization performance was examined. The results indicate that DEAB solvent has the best overall performance especially under the wetting conditions. It was noted that increasing liquid concentration, membrane length and decreasing gas flow rate enhance decarburization.