Modelling and process analysis of post-combustion carbon capture with the blend of 2-amino-2-methyl-1-propanol and piperazine

Recent pilot plant experiments have proved that a novel solvent blend of 2-amino-2-methyl-1-propanol (AMP) and piperazine (PZ) has better performance in energy saving than the traditional solvent monoethanolamine (MEA) for chemical absorption CO2 capture process. This paper presented the systemic study on modeling and process analysis of the CO2 capture process with an AMP + PZ aqueous solvent using Aspen Plus® software. A rate-based steady state process model was developed by updating the thermodynamic model and chemistry reactions with kinetic parameters of the AMP-PZ-H2O-CO2 system. The process model was validated with the experimental data and the results showed an excellent agreement. The process model was then scaled up to match the capacity of an industrial scale coal-fired power plant. A parametric study of the industrial scale model shows that the reboiler duty would be reduced upon lowering the CO2 removal rate, increasing the ratio of AMP in the solvent, and increasing the stripper pressure. Process configuration modifications, including intercooled absorber (ICA), lean vapor compressor (LVC) and rich solvent split (RSS), have been implemented and the energy demand were reduced by 6.7%, 2.7%, and 8.5% accordingly. The combination of ICA + LVC, ICA + RSS, and RSS + LVC modifications obtained an energy saving of 8.5%, 14%, and 9.3%, respectively. The combination of ICA + RSS + LVC reduced the energy demand by 15.2%.