Modeling of autothermal methane steam reforming. Comparison of reactor configurations

In the present work, two systems for the coupling of methane steam reforming and methane combustion have been studied and compared. In the first system considered, the two reactions are thermally coupled but take place in separate volumes. Particular attention has been placed on the choice of operating conditions in order to maximize the efficiency and safety of the process. The second system considered consists in a modification of the process of autothermal reforming, distributing the oxygen feed to the reactor along its axis. The results obtained have been compared with the performance of a reactor in which the oxidation reaction is carried out by injecting oxygen in different points along the reactor. The performance of the two systems has been compared with that of an autothermal reformer, in which the entire oxygen feed is mixed with steam and methane entering the reactor. The analysis of the different systems has focused on the temperature profiles that develop within the reactors, the amount of hydrogen produced per mole of methane fed, and the possibility of carrying out the process without entering flammability limits.