Consideration of a nitrogen-selective membrane for postcombustion carbon capture through process modeling and optimization

• A nitrogen-selective membrane was evaluated for postcombustion carbon capture.
• Energy consumption and membrane surface area were simultaneously minimized.
• All process designs achieved 90% CO2 capture and 95% product purity.
• The lowest energy consumption was found to be 1.1 GJ/tonne CO2 in a hybrid system.

The potential of a nitrogen-selective membrane for postcombustion CO2 capture from a coal-fired power plant was investigated in this study. Bi-objective optimization was performed using the nondominated sorting genetic algorithm II (NSGA-II) to simultaneously minimize energy consumption and membrane surface area requirement with targets of >90% CO2 capture and 95% purity. The properties of the nitrogen-selective membrane used in the calculation are based on measurements of nitrogen and hydrogen transport in vanadium at high temperatures (ca. 600 °C). The lowest energy consumption was found to be 1.1 GJ/metric ton CO2 with a hybrid nitrogen- and CO2-selective membrane system.