A SOFC system having a fuel reformer for reforming a gaseous hydrocarbon stream and steam into a hydrogen rich gas, a solid oxide fuel cell stack including an anode and a cathode for electrochemically reacting the hydrogen rich gas and a cathode air stream to produce electricity, an anode exhaust stream and a cathode depleted air stream. The anode exhaust stream and the cathode depleted air stream are kept separate, a burner for combusting a mixture of the anode exhaust stream and a fresh air stream to complete combustion and produce heat for the reformer control unit and a blower are also provided. The control unit controlling the blower for controlling the mass flow rate of the fresh air stream to provide heat to the reformer to reform the gaseous hydrocarbon stream and to produce a burner exhaust stream.

An object of the present invention is to provide a fuel cell system for preventing carbon deposition in a fuel cell stack to be supplied with reformed gas. A fuel cell system 10A of the present invention includes a partial oxidation reformer 22 for partially oxidizing raw fuel to produce carbon monoxide and hydrogen, a shift reactor 23 for shift reacting the carbon monoxide with steam to produce carbon dioxide and hydrogen, a fuel cell stack 20 for generating electric power by electrochemical reaction between oxidant gas and the hydrogen which is produced in at least one of the partial oxidation reformer 22 and the shift reactor 23, and an exhaust gas recirculation pipe P6 for supplying steam contained in exhaust gas of the fuel cell stack 20 to the shift reactor 23.

Disclosed are methods, systems, and computer-readable mediums for determining the composition of gaseous fuel. An initial gaseous fuel stream is provided that includes methane, non-methane hydrocarbons, and inert gases. Air is mixed into the initial fuel stream upstream of a first catalyst. The first catalyst oxidizes only the non-methane hydrocarbons of the initial fuel stream to produce a resultant fuel stream comprising methane and inert gases. Air is mixed into the resultant fuel stream downstream of the first catalyst and upstream of a second catalyst. The second catalyst oxidizes only the methane hydrocarbons of the resultant fuel stream to produce an output fuel stream. Mole ratios of the methane, the non-methane hydrocarbons, and the inert gases of the initial fuel stream are each determined.

Disclosed are methods for accommodating changes in the conditions of partial oxidation of hydrocarbonaceous feedstock by changing characteristics of the hot oxygen used in the partial oxidation.

Disclosed is methodology for controlling the H2:CO ratio of the product produced in a partial oxidation reactor, by adjusting the properties of the product formed in the partial oxidation.

A fuel cell system and method for using a peak shaving gas, the system including: a fuel inlet configured to receive fuel from a fuel source; a catalytic partial oxidation (CPOx) reactor configured to at least partially oxidize the fuel during startup of the system; a blower configured to provide air to the CPOx reactor; a gas analyzer configured to determine a composition of fuel provided to the CPOx reactor from the fuel inlet; an oxidation catalyst configured to reduce an O.sub.2 content of fuel received from the CPOx reactor; a reforming catalyst configured to partially reform fuel received from the oxidation catalyst; and a stack of fuel cells configured to generate electricity using fuel received from the reforming catalyst.

When a product gas producing operation is stopped, a purge operation is executed in which steam purge processing and product gas purge processing are sequentially performed. The steam purge is supplying, instead of a source gas, a product gas from a product gas tank to a reformer using a compressor, and supplying a reformed gas from a reforming processing unit to a plurality of adsorption towers, which perform a pressure swing adsorption operation, while the reformer is heated by a heating burner and steam is supplied to the reformer. The product gas purge is supplying the product gas from the product gas tank to the reformer using the compressor, and supplying the product gas from the reforming processing unit to the plurality of adsorption towers, which perform the pressure swing adsorption operation, while the supply of the steam is stopped and the heating of the reformer is maintained.

A method of maintaining a syngas composition ratio during an upset condition, including detecting a reduction in the import carbon dioxide flow rate with a carbon dioxide import stream flow sensor, evaluating the reduction in carbon dioxide flow rate or carbon dioxide pressure in a controller, performing one or more predetermined corrective actions as instructed by the controller. Wherein the predetermined corrective actions are chosen from the following: opening a CO2 import stream flow valve, opening a hydrocarbon and steam stream feed valve, opening a CO2 backup stream control valve, opening a syngas backup letdown valve, and starting a composition adjustment unit.

The device (100) for hybrid production of synthetic dihydrogen and/or synthetic methane comprises: an inlet (105) for a synthesis gas stream preferably comprising at least CO and H.sub.2, a catalytic conversion reactor (110), the following alternative configurations: a first configuration in which the operating conditions of the reactor promote a Sabatier reaction, so as to produce an outlet gas comprising mainly methane, or a second configuration in which the operating conditions of the reactor promote a water gas shift reaction, so as to produce an outlet gas comprising mainly dihydrogen; an outlet (115) for synthetic dihydrogen and/or synthetic methane and a control system (120) comprising a means (121) for selecting a configuration for operating the reactor and a control means (122) according to the selected configuration, the reactor being configured to operate according to a command.

This gas production system includes: a gas production device having a reactor forming a flow path for a treatment target gas, a first electrode and a second electrode to which voltage is applied, and a catalyst layer provided in the flow path and containing a catalyst; voltage generation means for generating voltage to be applied to the first electrode and the second electrode; and gas supply means for supplying the treatment target gas to the gas production device. The voltage generation means has frequency setting means for setting the frequency of the voltage in accordance with the treatment target gas, plasma generated between the first electrode and the second electrode is applied to the catalyst layer, and the treatment target gas is reformed to obtain a product gas.