Improved CO2 Absorption in a Gas–Liquid Countercurrent Column Using a Ceramic Foam Contactor

Abstract

Solid foams are porous, monolithic materials with higher specific surface areas than the random packings that are commonly used in amine-based CO2 capture processes. In this work, the hydrodynamic characteristics (e.g., pressure drop, flooding point, and liquid holdup) and CO2 absorption performance of α-Al2O3 ceramic foam packings of different porosities were investigated experimentally in a gas–liquid countercurrent column. With a 30 wt % diglycolamine (DGA) solvent as the CO2 absorbent, the foams allowed higher flow rates of gas and liquid than a random packing before undesirable flooding was reached. Ceramic foams with lower porosities have larger operating capacities than those with higher porosities. A parametric study of a one-dimensional flow model was performed by investigating the effects of gas velocity, liquid velocity, and CO2 solvent loading on the CO2 removal performance. Lower gas velocities and higher liquid velocities increased the CO2 removal efficiency. The CO2 removal efficiency decre...