CO2 Chemical Absorption with NH3 in Bubble Column and Packed Bed System: Modeling and Experiments

The chemical absorption of CO2 from a flue gas with aqueous NH3 is investigated both experimentally and theoretically. An equilibrium-based approach is proposed to model the reactions between the dissolved CO2 and NH3 in the liquid phase. Such an approach was then integrated into two different sets of balance equations for packed bed and bubble column systems, respectively. To validate the models, two sets of experimental campaigns were carried out under different operating conditions. The good agreement between computational and experimental results confirmed the effectiveness of the models, whose results might be useful to properly design, optimize and control the CO2 capture and the sorbent regeneration, whose energy demand depends on the chemical composition of the sorbent that can be suitably predicted by the developed models.