Practically Achievable Process Performance Limits for Pressure-Vacuum Swing Adsorption-Based Postcombustion CO2 Capture

• Published in: ACS sustainable chemistry & engineering 2021-03, Vol.9 (10), p.3838-3849
• Main Authors: Pai, Kasturi Nagesh, Prasad, Vinay, Rajendran, Arvind
• Format: Article
• Language: English
• ISSN: 2168-0485; 2168-0485
• DOI: 10.1021/acssuschemeng.0c08933

Practically achievable limits for pressure-vacuum swing adsorption (PVSA)-based postcombustion carbon capture are evaluated. The adsorption isotherms of CO2 and N2 are described by competitive Langmuir isotherms. Two low-energy process cycles are considered and a machine learning surrogate model is trained with inputs from an experimentally validated, detailed PVSA model. Several case studies are considered to evaluate two critical performance indicators, namely, minimum energy and maximum productivity. For each case study, the genetic algorithm optimizer that is coupled to the machine learning surrogate model searches tens of thousands of combinations of isotherms and process operating conditions. The framework pairs the optimum materials properties with the optimum operating conditions, hence providing the limits of achievable performance. The results indicate that pressures < 0.2 bar may be required to achieve process constraints for feeds with low CO2 compositions (