Exergy analysis of a hydrogen fired combined cycle with natural gas reforming and membrane assisted shift reactors for CO2 capture

Hydrogen production from fossil fuels together with carbon capture has been suggested as a means of providing a carbon free power. The paper presents a comparative exergetic analysis performed on the hydrogen production from natural gas with several combinations of reactor systems: (a) oxy or air fired autothermal reforming with subsequent water gas shift reactor and (b) membrane reactor assisted with shift catalysts. The influence of reactor temperature and pressure as well as operating parameter steam-to-carbon ratio, is also studied exergetically. The results indicate optimal power plant configurations with CO2 capture, or hydrogen delivery for industrial applications.

► Exergy analysis of NGCC with CCS.
► WGS-MR: exergetically efficient technology for CCS, less than 2% total exergy losses.
► 10% of total exergy dissipation in the ATR.
► Optimization of ATR operation and CO2 stream treatment.