CO₂ absorption characteristics in a random packed column with various geometric structures and working conditions

Abstract

CO2 emissions have been continuously increasing in recent years and exacerbating global warming, so CO2 emissions mitigation is of great benefit to the control of climate change. In this work, the computational models of CO2 absorption by aqueous ammonia solution in a random packed column are developed, where the packing porosity obeys the normal, empirical profile, piecewise constant distributions. The hydrodynamic and mass transfer performances, as well as the CO2 removal efficiency, are obtained by means of numerical simulation. The results show that the random packing with porosity following the normal distribution leads to a better mass transfer performance, thus a high CO2 removal efficiency. The height‐to‐diameter ratio of 3 is preferred due to the better CO2 absorption performance. More ammonia solution can form a bigger interfacial area, and thus enhance mass transfer performance. However, the increased CO2 flow rate is unfavorable to the CO2 absorption. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.