Abstract: A fuel processor for rapid start and operational control. The fuel processor includes a reformer, a shift reactor, and a preferential oxidation reactor for deriving hydrogen for use in creating electricity in a plurality of H2—O2 fuel cells. A heating and cooling mechanism is coupled to at least the shift reactor for controlling the critical temperature operation of the shift reactor without the need for a separate cooling loop. This heating and cooling mechanism produces or removes thermal energy as a product of the temperature of the combustion of air and fuel. Anode effluent and cathode effluent or air are used to control the temperature output of the heating mechanism. A vaporizer is provided that heats the PrOx reactor to operating temperature.

Abstract: A preferential oxidation reactor is provided including a plurality of reactor sections. The reactor sections are individually optimized for operating at a preferred reaction temperature. In one embodiment, each reactor subsection includes a respective coolant flow for manipulating the operating temperature of the respective subsection. In another embodiment, a first section includes a lower temperature catalyst substrate, a second reactor section includes a higher temperature (i.e. normal) catalyst substrate and a third reactor section includes a lower temperature catalyst substrate. Yet another embodiment includes modifying the catalyst substrates of the respective subsections through the inclusion of promoters. Still another embodiment includes varying a density of the catalyst substrate across the reactor sections. Each of the embodiments enable quick light-off of the reactor, while limiting a reverse water-gas shift reaction.

Abstract: An improved fuel processor thermal management system for use with a fuel cell is disclosed. The process includes supplying an air stream and a fuel stream into a auto thermal reactor (ATR) and forming reformate gas therein. Then, preferentially oxidizing the reformate gas and the air stream in the preferential oxidizer reactor (PrOx). The temperature of the preferential oxidizer reaction is controlled with a water stream by vaporizing the water stream to form a first portion of vaporized water. Then, reacting the air stream with the reformate gas exiting the PrOx is reached in a fuel cell to form an anode exhaust stream which is subsequently combined with the air stream to heat the water stream to form a second portion of vaporized water. The first portion of vaporized water and the second portion of vaporized water form a steam fluid.

Abstract: A stand-alone fuel processor (10) for producing hydrogen from a hydrocarbon fuel for a fuel cell engine in a vehicle. The fuel processor (10) includes a primary reactor (14) that dissociates hydrogen and other by-products from the hydrocarbon fuel as a reformate gas. The reformate gas is applied to a WGS reactor (48) to convert carbon monoxide and water to hydrogen and carbon dioxide. The WGS reactor (14) may include an adsorbent for adsorbing carbon monoxide. The reformate gas from the WGS reactor (48) is then sent to a rapid-cycle PSA device (12) for adsorbing the undesirable by-products in the gas and generates a stream of pure hydrogen. A liquid water separator (70) separates water from the reformate gas before it is applied to the PSA device (12). The PSA device (12) uses a portion of the separated hydrogen as a desorbing gas to purify the adsorbent in the PSA device (12). The by-products of the reformate gas can be used as a fuel in a combustor (30) that generates heat for the primary reactor (14).

Abstract: A fuel processor control system for a fuel cell stack includes water and fuel metering devices that control water and fuel provided to the fuel processor. An air flow rate sensor generates an air flow rate signal based on air flowing from a compressor to the fuel processor. A valve is located between the fuel processor and the fuel cell stack. A controller controls the valve and the water and fuel metering devices based on the air flow rate sensor. Other feedback signals such as stack voltage, stack cell voltage variation, pressure differential across the valve, and mass flow rate between the valve and the fuel cell stack can augment or be substituted for the air flow rate feedback signal. The fuel processor can be a partial oxidation reformer a steam reforming reactor, an auto thermal reformer or any combination thereof. The system may also include a water as shift reactor and a preferential oxidation reactor for carbon monoxide reduction.

Abstract: A catalytic combustor contains multiple sections for catalytically combusting an anode effluent. The anode effluent is divided into a plurality of portions with each portion routed to a different section or stage of the combustor. The proportioning of the anode effluent allows the combustor to be operated so that the flows combusted do not autoignite and various heat loads placed on the different stages of the combustor can be met. Additionally, the proportioning of the anode effluent allows the temperature within the various components of the combustor to be controlled so that a useful life of the combustor can be increased.

Abstract: A primary reactor for a fuel processor system that employs steam and air to convert a liquid hydrocarbon fuel into a hydrogen-rich gas stream. The liquid fuel and an air-steam mixture are mixed in a mixing region within the reactor. The fuel mixture is then directed through an electrically heated catalyst region that heats the mixture to the operation temperature of a light-off catalyst at system start-up. The heated fuel mixture is then directed through a light-off catalyst monolith where the hydrocarbon fuel is dissociated. Once the fuel mixture is heated to the operating temperature of the light-off catalyst, the electrically heated catalyst region is turned off because the exothermic reaction in the light-off catalyst monolith generates the heat necessary to sustain the catalytic reaction.

Abstract: A catalytic combustor contains multiple sections for catalytically combusting an anode effluent. The anode effluent is divided into a plurality of portions with each portion routed to a different section or stage of the combustor. The proportioning of the anode effluent allows the combustor to be operated so that the flows combusted do not autoignite and various heat loads placed on the different stages of the combustor can be met. Additionally, the proportioning of the anode effluent allows the temperature within the various components of the combustor to be controlled so that a useful life of the combustor can be increased.

Abstract: A fuel processor system includes first and second reactors each having an inlet that receives fuel from a fuel supply and an outlet that discharges a reformate containing hydrogen. The reactors are operable to reform the fuel to form the reformates. The second reactor is coupled in parallel with the first reactor with the reformates produced by each combining to form a reformate flow. The first reactor can be an autothermal reforming reactor and the second reactor can be a steam reforming reactor. The first and second reactors are controlled differently to provide quick startup and transient capability while providing improved overall efficiency under normal operation.

Abstract: An autothermal reformer is provided for a fuel cell system utilizing one volume and a plurality of inlets for both start-up and normal operation. In start-up mode, thermal combustion is employed for heating the catalyst reformation section of the reformer. Two inlets are used to feed air and fuel into the system, which are mixed and ignited in the common volume. Once the catalyst has reached light-off temperature, a second set of inlets provide air, steam and fuel into the common volume. The mixture then passes into the catalytic reformation system.

Abstract: A compact autothermal (partial oxidation and steam reforming) fuel reactor is provided for implementation with a fuel cell system. The reactor includes a premixing chamber for premixing a volume of air, steam and fuel into an effluent, a thermal POX reactor, a first stage reforming segment, a post-premix chamber, and a second stage reforming segment. Further provided are a water/fuel vaporizer for supplying steam and fuel as a gas to the premix chamber and an airflow cavity disposed about the reactor for pre-heating air supplied to the premix chamber. The thermal POX segment operates during an initial start-up period for pre-heating the other components of the reactor. Once the other components achieve an operation temperature, the first and second stage reforming segments catalytically reform the effluent. The premix and post-premix chambers enable variance in the O/C and S/C ratios to be achieved as the effluent is reformed through the multiple stages.

Abstract: A catalytic combustor contains multiple sections for catalytically combusting an anode effluent. The anode effluent is divided into a plurality of portions with each portion routed to a different section or stage of the combustor. The proportioning of the anode effluent allows the combustor to be operated so that the flows combusted do not autoignite and various heat loads placed on the different stages of the combustor can be met. Additionally, the proportioning of the anode effluent allows the temperature within the various components of the combustor to be controlled so that a useful life of the combustor can be increased.

Abstract: The present invention provides a combustor for a fuel processor which integrates a burner and a catalyst. The burner is utilized to quickly heat the catalyst to a light-off temperature to prepare it for normal operation. The heated catalyst is then used to react anode exhaust with air or cathode exhaust under normal operation.

Abstract: A preferential oxidation reactor is provided including a plurality of reactor sections. The reactor sections are individually optimized for operating at a preferred reaction temperature. In one embodiment, each reactor subsection includes a respective coolant flow for manipulating the operating temperature of the respective subsection. In another embodiment, a first section includes a lower temperature catalyst substrate, a second reactor section includes a higher temperature (i.e. normal) catalyst substrate and a third reactor section includes a lower temperature catalyst substrate. Yet another embodiment includes modifying the catalyst substrates of the respective subsections through the inclusion of promoters. Still another embodiment includes varying a density of the catalyst substrate across the reactor sections. Each of the embodiments enable quick light-off of the reactor, while limiting a reverse water-gas shift reaction.

Abstract: A method for designing a fuel processor having an optimized size (i.e., volume and mass) for use in a fuel cell system which provides electrical power in a plurality of power ranges. The method includes maximizing water availability in the fuel cell system and sizing the first CO reduction reactor to provide for peak fuel cell system operational efficiency in a most-used power range while sizing the second CO reduction reactor to ensure the fuel processor can components to operate at a desired maximum power. The method allows development of a fuel processor that has significantly lower total mass and volume, and shorter start-up time, than conventionally designed processors, yet can perform at a desired maximum power.

Abstract: A vaporizer is provided for vaporizing liquid in a fluid stream. The vaporizer includes at least two heat exchangers serially arranged in a direction of flow of the fluid stream through the vaporizer for vaporizing liquid in the fluid stream in stages. The heat exchangers each comprise a first plurality of thermally conductive flow channels through which the fluid stream flows and a second plurality of thermally conductive flow channels through which a heating stream flows and which are in heat exchange relationship with the first plurality of thermally conductive flow channels. A liquid supply means is provided for adding liquid to a downstream heat exchanger. The added liquid mixes with the vaporized stream exiting an upstream heat exchanger for vaporization in the downstream heat exchanger.

Abstract: The present invention relates to controlled staged rich combustion throughout a fuel processing system in order to improve start up performance. Multiple stages of air injection are used to burn rich combustion products within each component to provide direct heating thereof. During the start up cycle, the fluid temperature entering each reactor is increased and each component is heated to its operating temperature in parallel. The controlled staged rich combustion eliminates the load imposed upon a combustor within the system during the start up cycle. Thus, each of the components within the fuel processing system may be optimized for an operational mode rather than a start up mode.

Abstract: A fuel processor system capable of circulating fuel processor system gases, such as reformate, anode exhaust, and/or combustor exhaust, through the fuel processor to provide a number of distinct advantages. The fuel processor system having a plurality of fuel cells discharging an H2-containing anode effluent and an O2-containing cathode effluent. A fuel processor is also provided for converting a hydrogen-containing fuel to H2-containing reformate for fueling the plurality of fuel cells. A catalytic combustor is positioned in series downstream from the plurality of fuel cells and a vaporizer reactor is coupled to the catalytic combustor. A bypass passage is finally provided that interconnects an outlet of at least one of the group consisting of the fuel processor, the plurality of fuel cells, the catalytic combustor, and the vaporizer reactor to the inlet of the fuel processor. The bypass passage is operable to circulate a fuel processor system gas to the inlet of the fuel processor.

Abstract: The present invention provides a combustor for a fuel processor which integrates a burner and a catalyst. The burner is utilized to quickly heat the catalyst to a light-off temperature to prepare it for normal operation. The heated catalyst is then used to react anode exhaust with air or cathode exhaust under normal operation.

Abstract: A fuel processor control system for a fuel cell stack includes water and fuel metering devices that control water and fuel provided to the fuel processor. An air flow rate sensor generates an air flow rate signal based on air flowing from a compressor to the fuel processor. A valve is located between the fuel processor and the fuel cell stack. A controller controls the valve and the water and fuel metering devices based on the air flow rate sensor. Other feedback signals such as stack voltage, stack cell voltage variation, pressure differential across the valve, and mass flow rate between the valve and the fuel cell stack can augment or be substituted for the air flow rate feedback signal. The fuel processor can be a partial oxidation reformer a steam reforming reactor, an auto thermal reformer or any combination thereof. The system may also include a water as shift reactor and a preferential oxidation reactor for carbon monoxide reduction.