Sensitivity analysis of the rate-based CO2 absorber model using amine solutions (MEA, MDEA and AMP) in packed columns

Abstract

The modeling and simulation of CO2 capture processes with amine solutions are considered as important developments toward the detailed study and analysis of these processes. In the literature, the application of rate-based models for the modeling of CO2 capture processes by amine solutions has been proved superior to equilibrium-stage models. The results of rate-based models, however, depend strongly on the selection of model parameters such as physical properties, transport properties, kinetic models, and mass transfer correlations. In this study, sensitivity analysis was performed to investigate the effect of mass transfer correlations in combination with kinetic models on the performance of an absorber column. The reason for this investigation is to establish appropriate correlations that can be used for design of the CO2 capture process. Sensitivity analysis was performed using a rate-based model for capture of CO2 in monoethanolamine (MEA), methyldiethanolamine (MDEA), and 2-amino-2-methyl-1-propanol (AMP) solutions in packed columns containing structured and random packing. The model was successfully validated by comparison of obtained results with published experimental data. The sensitivity analysis revealed that the mass transfer correlations developed by Hanley and Chen (2012) to simulate a structured packing absorption column, obtained the best results in comparison with the other tested and analyzed correlations in this study. For a randomly packed column, the correlations suggested by Onda et al. (1968) exhibited the best results. The kinetic models tested and examined in this study had a determinant role in the results of the sensitivity analysis in a manner that reflected the assumptions used in development of the model such as the temperature and amine concentration ranges. Therefore, careful selection of the mass transfer correlations and kinetic models to be used in the rate-based absorber model is required for modeling of the CO2 capture process. Otherwise, serious errors in design of the CO2 capture process may result.