A New Integrated System for Carbon Capture and Clean Hydrogen Production for Sustainable Societal Utilization

Hydrogen production and carbon dioxide removal are considered two of the critical pieces to achieve ultimate sustainability target. This study proposes and investigates a new variation of potassium hydroxide thermochemical cycle in order to combine hydrogen production and carbon dioxide removal, synergistically. An alkali metal redox thermochemical cycle developed where the potassium hydroxide is considered by using a nonequilibrium reaction. Also, the multigeneration options are explored by using two stage steam Rankine cycle, multi-effect distillation desalination, Li-Br absorption chiller, which are integrated with potassium hydroxide thermochemical cycle for hydrogen production, carbon capture, power generation, water desalination, and cooling purposes. A comparative assessment under different scenarios is carried out. The energy and exergy efficiencies of the hydrogen production thermochemical cycle are 44.2% and 67.66% when the hydrogen generation reaction is carried out at 180°C and the separation reactor temperature set at 400°C. Among the multigeneration scenarios, a trigeneration option of hydrogen, power and water indicates the highest energy efficiency as 66.02%.