Heterogeneous reactor modeling for simulation of catalytic oxidation and steam reforming of methane

An autothermal, dual catalyst, fixed-bed reaction system proposed for hydrogen production from methane is mathematically investigated using different catalyst bed configurations and feed ratios. Consecutive placement or physical mixture of the oxidation and reforming catalysts, Pt/delta -Al2O3 and Ni/MgO-Al2O3, respectively, are the two configurations of interest. Reactor operation at different feed ratios is analyzed for both catalyst bed configurations on laboratory scale and industrial scale via a series of simulations by using one-dimensional heterogeneous fixed-bed reactor model. The type of heterogeneous components implemented into the model is decided by checking related criteria. Hydrogen production is predicted to be higher when the catalysts are in a physically mixed state as well as at low methane-to-oxygen and high steam-to-methane ratios, which are in agreement with the experimental results reported for a beach scale integral reactor. The optimum operating conditions for obtaining maximum hydrogen production are also investigated. (C) 2001 Elsevier Science Ltd. All rights reserved.