Comparative study of conventional steam-methane-reforming (SMR) and auto-thermal-reforming (ATR) with their hybrid sorption enhanced (SE-SMR & SE-ATR) and environmentally benign process models for the hydrogen production

Abstract The paper presents a comparison of steam methane reforming (SMR), sorption enhanced steam methane reforming (SE-SMR), auto-thermal reforming (ATR), and sorption enhanced auto-thermal reforming (SE-ATR) in a fixed bed reformer for hydrogen production. A one-dimensional, unsteady-state heterogeneous reactor model for each process which includes mass and thermal dispersion in the direction of flow and axial pressure distribution, has been simulated using gPROMS® 4.0.1 model builder, while CEA and Aspen Plus® have been employed to analyze the equilibrium performance and simulate the process flowsheets of individual process respectively. The performance of the individual hydrogen production process has been analyzed in terms of CH4 conversion (%), H2 yield (wt. % of CH4), H2 purity and CO2 capture under the various operating conditions of temperature (773–1473 K) and pressure (5–40 bar). The simulation results were also compared with the thermodynamic calculations and literature data. An excellent agreement was observed between our reactor modelling outputs and literature data. The operating conditions of 923 K, 30 bar and S/C of 3.0, O2/CH4 of 0.45 have been chosen. At these conditions, the CH4 conversion for SMR, SE-SMR, ATR, and SE-ATR was found to be 32%, 66%, 51%, and 76% respectively while the composition of hydrogen produced on a dry basis was 55%, 87%, 55%, and 92% respectively. It has been concluded that there are significant advantages of both sorption enhanced processes over conventional reforming in terms of CH4 conversion, H2 purity and the amount of H2 energy produced per unit CH4 energy consumed (MJ).