Cryogenic carbon capture as the bridge for integrating hydrogen production and Liquefaction: Enhancing the sustainability of blue hydrogen Production-to-Storage systems

Hydrogen is one of the promising energy vectors for sustainable energy systems because of its carbon-free combustion and high mass-energy density. However, most hydrogen production processes remain carbon-intensive, and the low volumetric energy density of hydrogen significantly hinders storage efficiency. To reduce carbon emissions during hydrogen production, amine-based chemical absorption methods are commonly employed. However, these methods face challenges, such as low capture efficiency and high energy demands. To improve storage efficiency, hydrogen liquefaction methods have been explored to reduce volume. Nevertheless, liquefaction methods require cryogenic operating temperatures, which result in high power consumption and substantial cost burdens. To address these issues, this study proposes a novel system that integrates hydrogen production and liquefaction processes by introducing cryogenic carbon capture (CCC). In the proposed system, CCC obtains cold energy through integration with the precooling cycle of the hydrogen liquefaction process, eliminating the need for additional refrigeration units. Consequently, the integrated system achieves a 99.99% carbon capture rate, with a 27.5% reduction in overall energy consumption. Moreover, the economic feasibility increased by 7.87%, and the CO₂ avoidance cost decreased by 58.5%. The carbon-techno-economic analysis results revealed that the carbon capture penalty can be offset at 52.5% lower carbon tax rates. Additionally, scenario studies revealed that the proposed system demonstrates 41.9% higher economic performance than liquefied green hydrogen systems while maintaining comparable environmental benefits.