Method for operating a combination partial oxidation and steam reforming fuel processor

Abstract

In one aspect, the present invention provides a method for operating a fuel cell system. The system comprises a reactor having one or more catalytic beds and is fed a hydrocarbon fuel along with air and steam. Where more than one catalytic bed is present, such catalytic beds are preferably arranged sequentially such that the outlet from one bed enters the inlet of the next bed. The catalytic beds are the regions where reactions among the hydrocarbon, air, and steam are catalyzed within the reactor. The method comprises supplying a stream of a fuel and air mixture to the reactor which is lean. The mixture is lean in that it has an excess amount of oxygen relative to the stoichiometric amount required for reaction with the fuel. The reactions occurring with the lean mixture heat the reactor. When there is more than one catalytic bed, the hot gases generated from one catalytic bed can be used to heat other catalytic beds. After sufficient heating of the reactor by the lean mixture, a fuel-rich stream is fed to the reactor. This fuel-rich mixture comprises fuel, air, and water in the form of steam. The mixture is rich in that fuel is fed in an excess amount relative to the amount of oxygen for a stoichiometric reaction. The reactions of the fuel-rich stream produce a product comprising hydrogen (H ).