Abstract: A variable-direction burner tip is coupled to a first actuator that, when actuated, alters a firing direction of the respective burner tip. A respective flexible hose may couple a fuel input to each burner tip to accommodate rotation of the respective burner tip. In a burner incorporating one or more variable-direction burner tips, the burner includes a burner throat having one or more burner throats therein, the burner throats being sized and shaped to accommodate variation in firing direction by at least one burner tip positioned within each of the burner throats.

Abstract: A low NOx burner for installation on a furnace wall has an elongated tube connected to a combustion air supply, the furnace side end of which mounts a combustion air spinner that is spaced from the furnace wall. A plurality of air ports extend through the wall into the combustion chamber. Downstream ends of the air ports are spaced from the furnace wall as well as from the spinner, and they are configured to bias the discharged air flow towards the spinner. A plurality of first fuel gas spuds with fuel gas discharge orifices arranged about the spinner and discharges fuel gas into the combustion chamber downstream of the spinner. A second fuel gas spud is disposed in pockets between adjacent pairs of air ports which are closed against the furnace wall so that no combustion air flows through the pockets. The third gas spuds are placed inside the air ports.

Abstract: A burner assembly that produces very low NOx emissions includes a plurality of furnace gas openings for receiving a portion of furnace gasses back into a combustion cylinder. The burner assembly includes the combustion cylinder, a plurality of combustion air inlet conduits that extend into the cylinder and a plurality of fuel gas discharge nozzles that also extend into the cylinder. The burner assembly is mounted within a combustion chamber of a furnace, wherein the walls of the combustion chamber are provided with or are made up of heat transfer pipes.

Abstract: A method and apparatus for preheating a furnace during a warm-up phase of furnace operation. The furnace has main burners with a tubular fuel supply surrounded by a main combustion air duct defining an annular space between the supply and the duct that extends in an axial direction of the main burner. A pilot nozzle in the annular space extends in an axial direction of the burner towards an interior of the furnace and discharges readily ignitable fluid fuel jets through orifices in the nozzle toward the interior of the furnace. Combustion air from the duct is directed past the nozzle and is mixed with the fuel discharged from the orifices to form an ignitable mixture that is ignited to form the furnace heating pilot flame downstream of the nozzle.

Abstract: A burner assembly that produces very low NOx emissions includes a plurality of furnace gas openings for receiving a portion of furnace gasses back into a combustion cylinder. The burner assembly includes the combustion cylinder, a plurality of combustion air inlet conduits that extend into the cylinder and a plurality of fuel gas discharge nozzles that also extend into the cylinder. The burner assembly is mounted within a combustion chamber of a furnace, wherein the walls of the combustion chamber are provided with or are made up of heat transfer pipes.

Abstract: A burner for installation in a furnace having a combustion chamber defined by at least a furnace front wall, two side walls, a top wall and a bottom wall as well as heat transfer pipes through which a heat transfer medium flows and which are arranged on at least one of the top, bottom and side walls. A burner assembly is mounted to the furnace front wall and has a tubular member with an open distal end that is located inside the combustion chamber. The other end of the tubular member is attached to the furnace front wall. Several combustion air ports extend into the tubular member from the other, proximal end thereof and are coupled to a source of combustion air. Several fuel gas discharge nozzles also extend into the tubular member from the other end thereof and are coupled to a fuel source.

Abstract: A low NOx burner for installation on a furnace wall. The burner has an elongated tube connected to a combustion air supply, the furnace side end of which mounts a combustion air spinner that is spaced a substantial distance from the furnace wall. A plurality of typically six elongated air ports extend through the wall from the windbox of the furnace into the combustion chamber and supply most of the required combustion air. Downstream ends of the air ports are spaced from the furnace wall as well as from the spinner, and they are configured to bias the discharged air flow towards the spinner. A plurality of first fuel gas spuds with fuel gas discharge orifices is arranged about the spinner and discharges fuel gas into the combustion chamber downstream of the spinner. A second fuel gas spud is disposed in pockets between adjacent pairs of air ports which are closed against the furnace wall so that no combustion air flows through the pockets.

Abstract: A burner assembly that produces very low NOx emissions includes a plurality of furnace gas openings for receiving a portion of furnace gasses back into a combustion cylinder. The burner assembly includes the combustion cylinder, a plurality of combustion air inlet conduits that extend into the cylinder and a plurality of fuel gas discharge nozzles that also extend into the cylinder. The burner assembly is mounted within a combustion chamber of a furnace, wherein the walls of the combustion chamber are provided with or are made up of heat transfer pipes.

Abstract: Embodiments of the present invention are directed to a low NOx duct burner or heater for efficiently heating turbine exhaust gases (TEG) in a less polluting manner. In one embodiment, a heater for heating a gaseous stream flowing in a downstream direction through a duct comprises a heating gas supply pipe extending at least partially across the duct. The heating gas supply pipe includes a plurality of spaced-apart gas pipe outlets to discharge a portion of a heating gas into the duct generally in the downstream direction. A flame shield extends from a location at or near the heating gas supply pipe at least partially across the duct. A plurality of gas supply spuds are disposed upstream of the flame shield. The gas supply spuds include a plurality of gas spud outlets to discharge another portion of the heating gas into the duct.

Abstract: Heat is extracted from an oxidizable component in an anode gas generated by a fuel cell. A heat exchanger is in fluid communication with the fuel cell, and the anode gas flows through a first portion of the heat exchanger. The heat exchanger is further in fluid communication with a source of an oxygen-containing gas, such as air, and has a second portion through which the air flows, so that the temperatures of the anode gas and the oxygen-containing gas tend to equalize in the heat exchanger. A downstream end of the heat exchanger is in fluid communication with a space where the anode gas and the air mix and form a mixture of anode gas and air. A first burner located upstream of the heat exchanger heats the air. A catalytic oxidizer is in fluid communication with the space and oxidizes the mixture. The catalytic oxidizer emits a heated effluent that is directed back to the fuel cell. A second burner heats the effluent during at least portions of the time during the operation.

Abstract: A heat recovery system includes an upstream superheater section and a duct burner arranged to provide improved performance. The upstream superheater section and duct burner are arranged to reduce the negative effects of heat extraction by the upstream superheater section on the duct burner operation. The arrangement provides a downstream flow from the upstream SH section that is temperature stratified and positions the duct burner elements in the areas of maximum temperature. The tubes of the upstream superheater section and the duct burner elements are arranged in a variety of ways to provide temperature stratification, for example, in the horizontal or vertical directions.

Abstract: A low NO.sub.x burner includes a refractory lined plate with a refractory side facing a combustion chamber. A multiplicity of combustion air passages extend through the plate toward the combustion chamber. A multiplicity of spaced-apart primary fuel nozzles each have a discharge opening being surrounded by one of the combustion air passages for directing fuel therethrough to mix with combustion air passing through the air passages. A multiplicity of anchor fuel nozzles project through the plate for directing fuel into the combustion chamber. The anchor fuel nozzles are spaced apart from each other and from the combustion air passages. The flows of fuel and combustion air through the primary and anchor nozzles and the air passages into the combustion chamber are controlled to generate a flame. In applications that require low excess air, such as boiler applications, the burner is modified by providing a secondary fuel and flue gas injection assembly to form a two-stage burner.

Abstract: An industrial fuel gas burner fired with a mixture of combustion air having up to about 45% flue gas which flows in a downstream direction along an annular combustion air conduit disposed about an axially movable core of the burner that terminates in an end cone that faces the combustion chamber of the furnace. Within the conduit and upstream of a discharge end thereof is a fuel gas discharge header formed by concentric, radially inner and outer tubular ring-shaped fuel gas headers which are concentrically disposed about an axis of the burner and in fluid communication with a source of pressurized fuel gas. The headers have a multiplicity of fuel gas discharge orifices which form three-dimensionally oriented gas streams directed into the combustion air-flue gas flow in the annular conduit. The orifices have a diameter of at least about 0.1 inch.

Abstract: A low NO.sub.x burner includes a primary air and fuel discharge assembly which, in turn, includes a burner plate having a plurality of slots from which fuel gas jets and combustion air are discharged. The slots are arranged such that the width of the recirculation zones between adjacent slots substantially varies between the central region of the burner plate and its perimeter. With this construction, the local ignition patterns vary such that local oscillations of flame front occur at different frequencies so that vibrations are greatly dampened and resonance problems in the furnace minimized or eliminated. In applications where high excess air is not desirable, such as boiler applications, the burner is modified by providing a secondary fuel and flue gas injection assembly to form a two stage burner. In the preferred embodiment, the secondary injection assembly includes a plurality of discrete fuel and flue gas injection tubes arranged around the primary air and fuel gas discharge assembly.

Abstract: A low NO.sub.x burner includes a burner plate having a plurality of slots from which fuel gas jets and combustion air are discharged. A plurality of fuel tubes are aligned with the slots for discharging the fuel gas therethrough. The fuel tubes are spaced from the slots so that combustion air, provided by a wind box, also can flow through the slots. The fuel gas and combustion air are discharged at high velocity, thereby generating very high turbulence in the combustion chamber downstream from the burner. The slots are arranged such that the width of the recirculation zones between adjacent slots substantially varies between the central region of the burner plate and its perimeter. With this construction, the local ignition patterns vary such that local oscillations of flame front occur at different frequencies and are not synchronized so that vibrations are greatly dampened and resonance problems in the furnace minimized or eliminated.

Abstract: A cooling system including a cooling duct adjacent to the hot air duct of an air heater. The cooling duct includes a first wall and a second wall spaced from the first wall such that a passageway is formed therebetween. A wire mesh sheet is arranged in the duct passageway. The wire mesh sheet comprises a plurality of layers of wire mesh and has an undulate configuration which together with its density prevents substantial heat radiation from the first wall of the cooling duct to the second wall without significantly impeding airflow through the cooling duct. Cooling air introduced into the cooling duct flows through the duct, removes heat, radiated by the first wall and absorbed by the wire mesh sheet, and carries that heat away from the duct as it exits through the outlet opening. In this way, the system cools the first wall and prevents any significant heat transfer to the second wall of the cooling duct and elements in the vicinity thereof.

Abstract: A burner suitable for use in conjunction with an air heater. The burner has a burner plate including a plurality of slots. The burner plate slots are aligned with and spaced from fuel supply tubes. The tubes have spaced apart orifices that discharge fuel gas in conical patterns and direct the gas jets through the slots in the burner plate and into the combustion chamber downstream from the burner. A baffle plate is positioned above the fuel supply tubes and extends across an air supply plenum. The baffle plate includes air discharge orifices through which the air from the plenum enters the burner in substantially uniform flow. The baffle plate orifices direct the air toward the burner plate for cooling. The air heated by the burner plate eventually flows toward and through the burner plate slots where it forms a layer between the fuel gas jets and the perimetrical surfaces and edges of the burner plate slots and, thus, maintains the fuel gas spaced from these surfaces and edges.