Effect of gravity center position on amine absorber with structured packing under offshore operation: Computational fluid dynamics approach

Abstract

The effect of the center of gravity (CoG) position on the CO2 removal efficiency was investigated for a pilot-scale amine absorber with Mellapak 250.X (M250X) structured packing subject to the pitching motion (i.e., 12s period and 1.57° amplitude). A porous medium Eulerian computational fluid dynamics (CFD) model with porous resistance, drag force between gas and liquid, and dispersion force was used to represent the hydrodynamic properties of M250X. Three CoG positions, namely, bottom of the column (Case 1), vertically under the column (Case 2), and diagonally under the column (Case 3), were considered for two different diameters of the absorber. Case 3 showed the biggest liquid maldistribution because of a long distance between the amine absorber and CoG position. The CO2 removal efficiency was lowest in Case 3 for the absorber having the larger column diameter. However, the difference between the CO2 removal efficiencies of Cases 2 and 3 was not substantial.