Exergy analysis of the solar thermochemical cycle for capturing CO_2 from air

摘要

This paper presents exergy analysis of the novel solar thermochemical cycle for CO_2 capture from ambient air. The exergy balance, the degree of the thermodynamic perfection, the influence coefficient and the exergy efficiency are determined for every element of the system. The proposed system has rather low exergy efficiency of 4.8%, mainly owing to the primary purpose of this system to capture CO_2 from air and not to produce energy. On the basis of exergetic analysis, possible ways of improving system performance are identified: increasing solar collector efficiency, pre-heating methane flow before the reforming reaction, recovering heat of the slaking process.