Information Derivation from Vapor-Liquid Equilibria Data: A Simple Shortcut to Evaluate the Energy Performance in an Amine-Based Postcombustion CO2 Capture

Evaluation of amine absorbents is crucial for the development of a technically and economically feasible CO2 capture process. However, the capture performance estimation usually requires a load of experiments, which is time-consuming and labor-intensive. The present study proposed a simple but effective shortcut that employs the fewest experimental data, i.e., vapor-liquid equilibria (VLE) data only, to estimate the CO2 capture performance by developing a validated chemical VLE model and a simple shortcut approach. The reliability of the proposed method was validated by the excellent agreement with the results from the laboratory and pilot plant experiments, and rigorous rate based MEA model in Aspen Plus. We demonstrated that this approach can reliably predict the important capture performance indicators, such as CO2 solubility, heat of CO2 reaction, lean/rich CO2 loadings and heat requirement of absorbent regeneration. Moreover, this shortcut approach can provide guidance for process modification to achieve the minimum regeneration energy. The extended application of this approach to other amines, i.e., piperazine (PZ), 2-amino-2-methyl-1-propanol (AMP), and blended PZ and AMP (PZ/AMP), also showed the good consistency with the published experimental and simulation results, further indicating the reliability of the shortcut approach to estimate the energy performance of amine processes. It is anticipated that the proposed method would simplify the evaluation of CO2 capture performance using VLE data only, providing an efficient and effective shortcut for screening and evaluating amine-based CO2 capture.