Modeling and Simulation of an Autothermal Reformer

The steady–state operation of the autothermal reformer is simulated as two reactors in series by means of a detailed mathematical model. An input-output model is selected to describe the upper combustion chamber. The possible occurrence of homogeneous steam reforming and watergas-shift (WGS) reactions is considered. The catalyst bed is represented through a one-dimensional heterogeneous model, which allows calculating the axial variations of composition, temperature and pressure of the process gas stream. The strong intraparticle diffusional limitations are taken into account by rigorous solution of the mass balances inside the catalyst particle. The gas-solid heat-transfer resistances are also evaluated. An intrinsic kinetics is used for the steam reforming and WGS reactions. Heat losses to the environment are considered. The influence of the main operating variables on the reactor performance is studied. The proposed mathematical has been checked successfully against data available in the open literature.