Abstract: A method and apparatus for producing a synthesis gas product having one or more oxygen transport membrane elements thermally coupled to one or more catalytic reactors such that heat generated from the oxygen transport membrane element supplies endothermic heating requirements for steam methane reforming reactions occurring within the catalytic reactor through radiation and convention heat transfer. A hydrogen containing stream containing no more than 20 percent methane is combusted within the oxygen transport membrane element to produce the heat and a heated combustion product stream. The heated combustion product stream is combined with a reactant stream to form a combined stream that is subjected to the reforming within the catalytic reactor. The apparatus may include modules in which tubular membrane elements surround a central reactor tube.

Abstract: A method and apparatus for producing heat used in a synthesis gas production process is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the steam reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5.

Abstract: A method and apparatus for producing a synthesis gas product having one or more oxygen transport membrane elements thermally coupled to one or more catalytic reactors such that heat generated from the oxygen transport membrane element supplies endothermic heating requirements for steam methane reforming reactions occurring within the catalytic reactor through radiation and convention heat transfer. A hydrogen containing stream containing no more than 20 percent methane is combusted within the oxygen transport membrane element to produce the heat and a heated combustion product stream. The heated combustion product stream is combined with a reactant stream to form a combined stream that is subjected to the reforming within the catalytic reactor. The apparatus may include modules in which tubular membrane elements surround a central reactor tube.

Abstract: An interconnect element for electrically connecting an anode and a cathode in adjacent fuel cells in a fuel cell stack, wherein said interconnect element has at least one featured surface including dimples, bosses, and/or pins arranged in a two-dimensional pattern. Preferably, both surfaces are featured, as by mechanical dimpling, embossing, or chemical etching, so that protrusions of the interconnect surface extend into either or both of the adjacent gas flow spaces to make electrical contact with the surfaces of the anode and cathode. This permits conduction of heat from the anode. The protrusions create turbulence in gas flowing through the flow spaces, which increases hydrogen consumption at the anode and hence electric output of the cell.

Abstract: An emergency shutdown apparatus for a solid-oxide fuel cell system, including a fuel cell stack, comprises a reservoir containing a reducing fluid, a valve enabling or preventing flow of the reducing fluid from the reservoir to the fuel cell stack, a timing circuit operating and controlling the valve, and a battery powering the timing circuit. The apparatus for an emergency system shutdown is able to operate independently of the main power plant and does not require any active control from the solid-oxide fuel cell system. The disclosed apparatus is entirely a stand-alone component that may be added to any conventional solid-oxide fuel cell system. The apparatus in accordance with the invention can be recharged, allowing the same hardware to be used over and over, however, a disposable unit could be used if found to be desirable.

Abstract: An SOFC fuel cell stack system in accordance with the invention including a recycle flow leg for recycling a portion of the anode tail gas into the inlet of an associated hydrocarbon reformer supplying reformate to the stack. The recycle leg includes a controllable pump for varying the flow rate of tail gas. Preferably, a heat exchanger is provided in the leg ahead of the pump for cooling the tail gas via heat exchange with incoming cathode air. A low-wattage electrical reheater is also preferably included between the heat exchanger and the pump to maintain the temperature of tail gas entering the pump, during conditions of low tail gas flow, at a drybulb temperature above the dewpoint of the tail gas.

Abstract: An improved multiple-tube catalytic reformer comprising a tubular body containing a radiator core having a plurality of longitudinal cells for low-pressure flow-through of combustion gases, the core being formed preferably either by winding of corrugated metal or as an extruded metal monolith. A plurality of reformer tubes, preferably non-cylindrical, containing hydrocarbon catalyst are arrayed in longitudinal openings within the radiator core and preferably are brazed thereto to maximize heat transfer from the radiator core to the reformer tubes. During manufacture, the metal radiator core is economically bored by laser cutting to form the openings to admit the reformer tubes for brazing. Preferably, the reformer tubes are numbered, sized, shaped, and arrayed to minimize the longest conduction path in the radiator core to the center of any reformer tube.

Abstract: A method for fueling a solid oxide fuel cell stack is provided. The method includes passing a first portion of hydrocarbon fuel through a catalytic hydrocarbon reformer to generate a first reformate. The first reformate is passed through a hydrocarbon cracker to generate a second reformate such that a portion of any non-reformed hydrocarbon fuel in the first reformate is converted to methane. The second reformate is supplied to the fuel cell stack.

Abstract: In an SOFC stack system, wherein a CPOx reformer supplies reformate to the stack, a portion of the anode tail gas is recycled directly into the anode inlet of the stack, such that the fuel reaching the anodes is a mixture of fresh reformate and recycled anode tail gas and is present at a sufficiently high temperature that endothermic reforming of residual hydrocarbons from the CPOx reformer occurs within the stack. Preferably, an amount of secondary non-reformed fuel is also added to optimize the fuel mixture presented for internal reforming. The anode tail gas is hot, at the stack temperature of 750-800° C., which allows for the mixture of anode tail gas and secondary fuel to be mixed and reacted in a clean-up catalyst to react higher hydrocarbons in the secondary fuel, without additional oxygen, prior to being mixed with reformate and sent to the stack.

Abstract: A method, device, and apparatus for tracing a conductive line and locating any concealed surveillance devices coupled to the line uses a signal generator to produce a test signal having a fundamental frequency which is coupled to the line under test. The test signal flowing through the line under test creates electromagnetic waves that propagate through the atmosphere away from the line. A portable locator probe is used to detect the radiated signal and thus the conductive line by detecting the magnitude of the radiated signal. As the locator probe is moved closer to the line, the amplitude of the detected signal increases. In addition, the portable locator probe detects harmonic signals radiated from nonlinear junctions coupled to the line at harmonic frequencies of the fundamental test signal.

Abstract: A housing rotatably supports a desiccant wheel, Ambient air passes through one part of the housing and hot exhaust air passes through the other part. As the wheel rotates, it absorbs moisture from the ambient air in part of the housing and desorbs moisture into the exhaust air in the other part. A fuel cell system supplies the hot exhaust air directly to the desiccant wheel, The dry ambient air is directed to an evaporative cooler and divided between dry channels and wet channels, The air passing through the dry channels cools to be directed to a conditioned space. The air passing through the wet channels evaporates water in the channels facilitating heat transfer and adding moisture to that air. The air from the wet channels is optionally added back into the air from the dry channels to provide appropriate humidity.

Abstract: An improved multiple-tube catalytic reformer comprising a tubular body containing a radiator core having a plurality of longitudinal cells for low-pressure flow-through of combustion gases, the core being formed preferably either by winding of corrugated metal or as an extruded metal monolith. A plurality of reformer tubes, preferably non-cylindrical, containing hydrocarbon catalyst are arrayed in longitudinal openings within the radiator core and preferably are brazed thereto to maximize heat transfer from the radiator core to the reformer tubes. During manufacture, the metal radiator core is economically bored by laser cutting to form the openings to admit the reformer tubes for brazing. Preferably, the reformer tubes are numbered, sized, shaped, and arrayed to minimize the longest conduction path in the radiator core to the center of any reformer tube.

Abstract: A solid-oxide fuel cell stack assembly comprising a plurality of sub-stacks, preferably two sub-stacks each containing one-half the total number of fuel cells. Cathode air and fuel gas are passed through the first sub-stack, wherein they are partially reacted and also heated. The exhaust cathode air and the exhaust fuel gas from the first sub-stack are directed to the respective inlets of the second sub-stack, becoming the supply cathode air and fuel gas therefor. A first heat exchanger in the flow paths between the sub-stacks and a second heat exchanger ahead of the sub-stacks can help to balance the performance of the two stacks. The result of dividing the number of cells into a plurality of sub-stacks, wherein the exhaust of one sub-stack becomes the supply for the next sub-stack, is that fuel efficiency and utilization are improved, thermal stresses are reduced, and electrical power generation is increased.

Abstract: An emergency shutdown apparatus for a solid-oxide fuel cell system, including a fuel cell stack, comprises a reservoir containing a reducing fluid, a valve enabling or preventing flow of the reducing fluid from the reservoir to the fuel cell stack, a timing circuit operating and controlling the valve, and a battery powering the timing circuit. The apparatus for an emergency system shutdown is able to operate independently of the main power plant and does not require any active control from the solid-oxide fuel cell system. The disclosed apparatus is entirely a stand-alone component that may be added to any conventional solid-oxide fuel cell system. The apparatus in accordance with the invention can be recharged, allowing the same hardware to be used over and over, however, a disposable unit could be used if found to be desirable.

Abstract: In a solid-oxide fuel cell system, a fuel/air manifold conveys air and tail gas fuel from the anodes in a fuel cell stack assembly to a tail gas combustor, producing a heated combustor exhaust having the highest mass flow in the system. The exhaust is passed through a heat exchanger to warm incoming cathode reaction air, and the exhaust is partially cooled by the exchange. From the heat exchanger, the exhaust gas is passed through a tempering jacket space surrounding the fuel cells in the stack. During start-up of the system, the exhaust gas is hotter than the stack and so the warm-up period is shortened. During normal operation of the system, the exhaust gas is cooler than the operating temperature and therefore cooling of the stack is assisted by contact with the exhaust gas.

Abstract: In an SOFC stack system, a reformer supplies reformate to the stack. An anode tail gas portion is recycled into the reformer. An inline flowmeter indicates an apparent recycle flow rate. A map of anode tail gas composition as a function of fuel utilization efficiency U, reformer oxygen/carbon ratio O:C, and recycle percentage R is generated on a laboratory test bed at various recycle rates and fuel utilization rates. Compositions are sent through a flowmeter and a Coriolus mass flowmeter provide a Coriolus flow and sensor voltage function across the various compositions and flow rates to create an average curve and an average (reference) voltage at a given flow. A scale factor Z is calculated and used to determine a scaled sensor voltage X for use in an average flow polynomial curve fit equation to calculate tail gas mass flow rate at any flow value indicated by the flow meter.

Abstract: In a solid-oxide fuel cell system, the fuel cell stacks, the fuel reformer, tail gas combuster, heat exchangers, and fuel/air manifold, are contained in a “hot zone” within a thermal enclosure. A separate and larger structural enclosure surrounds the thermal enclosure, defining a “cool zone” outside the thermal enclosure for incorporation of “cool” components such as the air supply system and the electronic control system. To prevent unwanted temperature rise in the cool zone during shutdown, from residual heat escaping from the hot zone through the thermal enclosure, the structural enclosure is provided with vents through the lower and upper walls thereof to permit thermal convective circulation of air through the enclosure. The vents are baffled to prevent entry of splash and other contaminants, and the lower vent is provided with a float valve to prevent flooding of the enclosure in event of immersion of the SOFC system.

Abstract: In a fuel cell assembly, nickel-based anodes are readily oxidized when exposed to oxygen as may happen through atmospheric invasion of the assembly during cool-down following shutdown of the assembly. Repeated anode oxidation and reduction can be destructive of the anodes, leading to cracking and failure. To prevent such oxygen migration, oxygen getter devices containing oxygen-gettering material such as metallic nickel are provided in the fuel passageways leading to and from the anodes. Oxidation of the oxygen-gettering material is readily reversed through reduction by fuel when the assembly is restarted.

Abstract: In a solid-oxide fuel cell system, an integrated air supply system provides oxygen for the fuel cell cathode reaction via a first air flow through a heat exchanger and a second air flow bypassing the heat exchanger, at least one of the first and second flows being throttled by a control valve responsive to a fuel cell control system, the flows subsequently being combined to provide air to the cathodes at a desired temperature.

Abstract: In a solid-oxide fuel cell system, a catalytic reformer unit provides reformate fuel for use by the cells in generating electricity. Both the reformer and the fuel cells require elevated temperatures for satisfactory operation. The reformer unit is provided with a combustion chamber and igniter ahead of the catalytic reformer plates such that, during start-up, fuel/air mixture normally destined for reformation may be ignited in the combustion chamber to provide a hot combustion exhaust which is fed through the catalytic reformer and the anode reformate flow spaces to assist in rapidly bringing the fuel cell system to operating temperature.