Modelling of H₂ production in a packed bed reactor via sorption enhanced steam methane reforming process

The sorption enhanced steam reforming (SE-SMR) of methane over the surface of 18 wt. % Ni/ Al₂O₃ catalyst and using CaO as a CO₂-sorbent is simulated for an adiabatic packed bed reactor. The developed model accounts for all the aspects of mass and energy transfer, in both gas and solid phase along the axial direction of the reactor. The process was studied under temperature and pressure conditions used in industrial SMR operations. The simulation results were compared with equilibrium calculations and modelling data from literature. A good agreement was obtained in terms of CH₄ conversion, hydrogen yield (wt. % of CH₄ feed), purity of H₂ and CO₂ capture under the different operation conditions such as temperature, pressure, steam to carbon ratio (S/C) and gas mass flux. A pressure of 30 bar, 923 K and S/C of 3 can result in CH₄ conversion and H₂ purity up to 65% and 85% respectively compared to 24% and 49% in the conventional process.