Eco-techno-economic analysis of onboard membrane carbon capture and storage systems considering CO2/N2 and CO2/O2 selectivity improvements

The shipping industry aims to achieve net zero emissions, and compact-sized membrane-based onboard carbon capture and storage systems can be a feasible solution. However, most previous studies have overlooked the importance of CO 2 /O 2 separation performance, leading to higher energy consumption and operating expenditures. In this study, a three-stage membrane carbon capture system was integrated with a precooled Linde–Hampson liquefaction process to minimize CO 2 avoidance costs while adhering to the FuelEU Maritime regulations. Two case studies assessed the impact of CO 2 /N 2 and CO 2 /O 2 selectivity improvements: one with a fixed greenhouse gas intensity target (62.90 g CO2eq /MJ, 2040–44 target) and another with varying targets. The results show that enhancing selectivity for not only CO 2 /N 2 but also CO 2 /O 2 is essential for developing cost-effective and energy-efficient onboard membrane carbon capture and storage systems, making it a feasible solution.