Abstract: A gas burner has a perforated, hollow body around and defining a combustion chamber. Gaseous fuel is fed to one side of the body, combustion occurs on the other side and the perforations provide a spatial connection between the fuel feed side and the combustion side. The new burner reduces exhaust gas emissions and offers a wide range of performance in the amount of heat energy provided, in the permissible range of gas pressure and in the range of fuels and fuel/air mixtures that can be used with it.

Abstract: Flame outlet rail for a gas burner of the atmospheric, pre-mix type. The rail includes a shell defining a plenum closed at one end and open at another end to receive an air/fuel mixture and having a length between the ends. The shell has a longitudinal orifice extending along the length of the shell. A grid made of sheet metal pierced by a series of rectangular slits is positioned over the longitudinal orifice of the shell and communicates an interior of the shell with the exterior thereof to permit the air/fuel mixture to flow therethrough so as to form a flame front upon ignition. The grid has a longitudinal axis in parallel with the longitudinal orifice and a length. The slits which extend perpendicular to the longitudinal axis, are distributed on either side of the longitudinal axis and form a sinusoid extending over the entire length of the grid, which increases a length of the flame front. The slits (2) are spaced apart by a distance, e, constant along the longitudinal axis (3) of the flame outlet grid.

Abstract: This invention concerns a combustible gas atmospheric burner of the so-called "small-ramp type", comprising at least a body (1) consisting of two half-shells in a vertical plane of symmetry, configured in the lower part as a venturi tube (4), wherein the mixture of combustible gas and air is introduce by way of a nozzle (18). In its upper part it has a head made of high-temperature resisting material where the combustion takes place. The upper part of the burner body has portions of different cross-section so that the mixture exits from the said head in such a manner that its output is essentially uniform and of a laminar nature along the entire longitudinal dimension, which gives rise to a reduction in the noise emitted by the burner, as compared with similar arrangements of a known type.

Abstract: A combined log set and gas burner system comprises a plurality of reinforced ceramic fiber burner elements formed in the shape of artificial logs and or glowing embers or a non-porous bed of coals. The burner elements are formed with a gas passageway in the interior of the element and a plurality of gas jets are made which connect the surface of the burner elements to the gas passageway in the burner elements. A source gaseous fluid is connected to the passageways to complete the combination burner system which eliminates the need for a separate burner apart from the log system.

Abstract: A catalytic combustion type heater set so as to reduce the exhaust emission at the time of ignition and the time of extinguishment by, at the time of ignition, providing a precombustion period and making the amounts of the fuel and air fed larger than the air-fuel ratio of the steady combustion period to prevent incomplete combustion and by, at the time of extinguishment, stopping the feeding of fuel and feeding only air in an amount lower than that before the fuel stops being fed so as to completely burn the remaining fuel, then feeding purging air.

Abstract: A gas catalytic heater having an improved temperature distribution is disclosed which includes a body having an open end in which is disposed a porous catalytically active layer containing a catalyst such as platinum metal. A sealed plenum chamber is disposed below the catalytically active layer and has a gas-permeable wall portion facing toward the active layer and a gas inlet orifice for introducing a fuel gas into the chamber. The gas-permeable wall portion may comprise a perforated metal plate having a plurality of tiny apertures the total open area of which is significantly less than that provided by perforated plates used in catalytic heaters of the prior art.

Abstract: In an evaporation burner with a combustion chamber (1) for a heater or the like with a peripheral boundary wall (29), a front boundary wall (6) and an air-supply nozzle (8) projecting coaxially into the combustion chamber (1) with radial air outlets (9) through the nozzle wall, a guiding device (32) for a whirling air supply is fitted at or upstream of the air supply nozzle (8) of the combustion chamber (1), in which said air supply nozzle has a diaphragm (10) for axial back-flow (R) of the exhaust gas or the air at the center of turbulence of the whirling air supply (L). In an axial extension of the combustion chamber may be fitted a coaxial flame pipe (20), which together with the peripheral boundary wall (2), may constitute a one-piece (deep-drawn) sheet-metal component and the rest of the combustion chamber may be a cast component.

Abstract: A gas fired infrared radiation emitter which contains a back-body provided with a distributor, a primary radiator having a combustion surface, and frame which contains four receptacles, each of which is integrally connected to the frame. A screen is removably attached to the frame receptacles by means of two bars, each of which is disposed within the receptacles and is free to move within the receptacles in either direction for a distance of at least about 0.15 inches. Stop surfaces are provided, however, for limiting the amount of longitudinal movement of the bars within the receptacles. The bars each have a length which does not exceed the length of the frame; and they can readily be removed from the receptacles.

Abstract: A burner apparatus for gas-fired appliances, such as gas furnaces. The burner apparatus includes an improved flame holder structure for controlling the shape and contour of the flame, and burner housing and plenum configurations for enhancing the characteristics of the flame.

Abstract: A burner apparatus for gas-fired appliances, such as gas furnaces. The burner apparatus includes an improved flame holder structure, with a contoured surface, for controlling the shape and contour of the flame, and burner housing and plenum configurations for enhancing the characteristics of the flame.

Abstract: The present invention relates to porous mat gas fired radiant burner panels utilizing improved reverberatory screens. The purpose of these screens is to boost the overall radiant output of the burner relative to a burner using no screen and the same fuel-air flow rates. In one embodiment, the reverberatory screen is fabricated from ceramic composite material, which can withstand higher operating temperatures than its metallic equivalent. In another embodiment the reverberatory screen is corrugated. The corrugations add stiffness which helps to resist creep and thermally induced distortions due to temperature or thermal expansion coefficient differences. As an added benefit, it has been unexpectedly discovered that the corrugations further increase the radiant efficiency of the burner. In a preferred embodiment, the reverberatory screen is both corrugated and made from ceramic composite material.

Abstract: A portable catalytically heatable appliance is provided. The appliance includes a catalyst support structure to flamelessly combust liquid or gaseous fuel and thereby provide a lower temperature heat source than a heat source that combusts fuel via flame. The fuel is ignited inside the catalytic support structure by a spark electrode. The ignition of the fuel inside the structure obviates the need for separate flame arresters. The ignition system includes a piezoelectric device that causes a voltage potential to form between the electrode and the catalytic support structure. A spark jumps from the electrode to an interior surface of the structure and ignites the fuel inside the structure, causing a flame to propagate. The flame heats the catalytic structure to an activation temperature, after which the fuel is combusted flamelessly on the surface of the catalytic structure.

Abstract: A gas premix burner in which gas and air are mixed in a suction region of an impeller to form a combustion mixture. The impeller is associated with a blower housing and an electronic control circuit board, all of which are arranged upstream in a blower chamber having at least one flame separating wall. The arrangement prevents the gas and the combustion mixture from reaching the motor landings or the printed circuit board.

Abstract: A fuel-fired water heater is provided with a flame spreader-type fuel burner assembly that reduces the operating NOx emissions of the water heater. The assembly includes a radial port gas burner coaxially disposed in a facing relationship with a generally inverted dish-shaped flame spreader which intercepts and is impinged on its concave side by the burner flames. In various disclosed embodiments of the flame spreader, during operation of the burner the burner flames pass through spaced series of openings extending through the flame spreader body inwardly of its outer edge periphery instead of being deflected horizontally outwardly past such periphery before passing upwardly beyond the flame spreader. The passage of the previously generated burner flames through these various openings serves to materially reduce the burner NOx emissions compared to a burner having an associated flame spreader with a conventional imperforate construction.

Abstract: A premix gas burner has a flat, composite burner plate formed by a rear flat plate having a first set of apertures and a forward flat and thinner plate having a second set of apertures of less diameter than the first set of apertures. The plates are connected to form a composite burner plate at the front end of a burner tube. A pilot tube extends through the burner tube and a pilot flame ignitor includes an insulated center electrode and a spirally wrapped grounding electrode electrically engaging the I.P. of the pilot tube to form an electrical ground. The electrodes spark to ignite a pilot flame which in turn ignites the larger burner flame.

Abstract: A low emission combustion system for use in a fuel-fired apparatus includes a fuel-fired burner (30) operative for generating a flame extending substantially axially outwardly from the outlet of the burner, a heat transfer tube (40) opposed to the outlet of the burner whereby the flame extending from said burner passes into a flame inlet section (48) of the gas flow conduit (46) of the heat transfer tube, a radiator body (50) disposed within the flame inlet section of the gas flow conduit of the heat transfer tube, and a catalytic converter (60) for oxidizing carbon monoxide to carbon dioxide. The radiator body (50) has a thermal mass sufficient to reduce peak flame temperatures in the flame inlet section to less than 2800 F. The catalytic converter is disposed within the gas flow conduit at a location downstream of the radiator body.

Abstract: A drying apparatus comprising a cylindrical drum (1) for drying, on the outside surface of the drum (1), pulp-shaped and viscous substances, such as for instance coffee milk powder, or band-shaped products, such as for instance paper, cardboard or textile, the apparatus comprising means for heating the drum (1) from the inner space of the drum (1), the means for heating the drum from the inner space of the drum (1) comprising a number of gas burners (2) juxtaposed in axial direction of the drum and controllable independently of one another. In furher elaboration of the invention, the gas burners are radiant burners.

Abstract: The invention concerns a two-stage catalytic burner (1) with at least one feed (3) for a hydrogen or hydrocarbon-containing fuel gas and at least one feed (17) for a combustion gas such as oxygen or air, two combustion stages (15, 16), the second (16) of which is a monolithic burner through which the mixture of gases leaving the first stage (15) passes, and a heat exchanger (8) connected to the burner (1). The first combustion stage (15) is a diffusion burner in which a chamber (6) containing fuel gas is separated from the chamber (7) containing combustion gas by a catalytic layer (burner element 4) which is permeable to the fuel gas. The burner element (4) is made of highly porous catalytically active material with a porosity of >50% and pore size of 0.001 to 100 .mu.m and has a thickness of 0.05 to 10 mm. The fuel gas is fed into chamber (6) and the combustion gas into chamber (7).

Abstract: A porous silicon carbide insert is located in the burner and defines the burner head. This provides a larger area for the flame to attach to the burner head since the porous insert causes the gas/air mixture to flow from the entire burner head. A more stable flame results and the flame is unable to travel back into the burner venturi through the insert.

Abstract: A porous surface radiant burner assembly provided with a porous burner substrate having a surface including a layer of zircon and an overlying layer of zirconia formed in situ upon exposing the zircon layer to radiant burner operating conditions. The porous surface burner substrate can be in the form of a mat of randomly oriented fibers coated with zircon, a solid parted plate of zircon or a different ceramic provided with a coating layer of zircon, or a reticulated foam comprising either zircon or a different ceramic material coated with zircon. Preferably in the method of making the porous burner substrate, the zircon layer is merely exposed to the intended operating conditions of the radiant burner wherein during the initial degradation of the zircon layer, a continuous, adherent layer of zirconia is formed in overlying relationship to the layer of zircon to resist further degradation.

Abstract: The fuel in the fuel rich inner cone of the flame is catalyzed by a partial oxidation catalyst into carbon monoxide and hydrogen which have a lower peak flame temperature thereby reducing thermal NO.sub.x. The insert is heated and radiates heat with a further reduction of peak flame temperature.

Abstract: The method of combusting lean fuel-air mixtures comprising the steps of:a. obtaining a gaseous admixture of fuel and air, said admixture having an adiabatic flame temperature below a temperature which would result in any substantial formation of nitrogen oxides but above about 800.degree. Kelvin,b. contacting at least a portion of said admixture with a catalytic surface and producing reaction products,c. passing said reaction products to a thermal reaction chamber, thereby igniting and stabilizing combustion in said thermal reaction chamber.

Abstract: The method of combusting lean fuel-air mixtures comprising the steps of:a. obtaining an admixture of fuel and air, said admixture having an adiabatic flame above about 900.degree. Kelvin;b. passing least a portion of said admixture into contact with one or more mesolith combustion catalysts operating at a temperature below the adiabatic flame temperature of said admixture thereby producing reaction products of incomplete combustion; andc. passing said reaction products to a thermal reaction chamber;thereby igniting and stabilizing combustion in said thermal reaction chamber.

Abstract: The method of combusting lean fuel-air mixtures comprising the steps of:a. obtaining a gaseous admixture of fuel and air, said admixture having an adiabatic flame temperature below a temperature which would result in any substantial formation of nitrogen oxides but above about 800.degree. Kelvin,b. contacting at least a portion of said admixture with a catalytic surface and producing reaction products,c. passing said reaction products to a thermal reaction chamber, thereby igniting and stabilizing combustion in said thermal reaction chamber.

Abstract: A multilayer matrix burner which has exceptionally low NO.sub.x emissions can be operated over a broad turndown range. The burner is, in effect, a three-dimensional matrix of spaced apart emissive layers. There is a first three-dimensional porous layer which acts to distribute a fuel/air mixture. There is a wider gap (which may be adjustable) between the distributive layer and one or more two-dimensional porous emissive layers. An exemplary emissive layer is a refractory wire screen. Preferably, there are multiple such emissive layers with a narrower gap between successive layers. Preferably, the porosity increases in each successive layer downstream from the preceding layer. This arrangement provides a stable flame wherein most of the combustion occurs adjacent to successive incandescent emissive layers. Preferably the successive layers in the downstream direction have a large open area for transmitting radiant energy from preceding emissive layers. Such high intensity burners, e.g. 1,500,000 BTU/h.multidot.

Abstract: A non-abrading gasket assembly comprised of an upper ceramic fiber gasket having a generally rectangular configuration. The upper ceramic gasket has a hollow opening within joined long edges and short edges thereof. A lower ceramic fiber gasket has a generally rectangular configuration. The lower ceramic gasket has a hollow opening within joined long edges and short edges thereof. The lower ceramic fiber gasket and the upper ceramic fiber gasket have identical dimensions. The device contains an interior steel gasket having a generally rectangular configuration. The steel gasket has a plurality of apertures formed therethrough inwardly around a peripheral edge thereof. The steel gasket has a downwardly extending aperture formed through a central portion thereof. The interior steel gasket is dimensioned to be coupled between the upper ceramic fiber gasket and the lower ceramic fiber gasket.

Abstract: A gas burner of the type in which a inflammable mixture is caused to flow out of a diffuser, is formed of a plurality of parallel slots separated by grid elements, and distributed into a pair of grids separated by an elongate screen extending between the two grids. The burner includes at least one elongate slot extending perpendicular to said screen along the width of said grid pair, perpendicular to the screen, near the grids, and adapted to take up relative dimensional variations of said screen and the grid elements brought about by differential heatings of the screen and the burner walls surrounding the diffuser.

Abstract: A method and apparatus for producing a gas-fired flame which simulates a wood-burning flame. The apparatus includes an elongated slot which is port loaded to produce a buoyancy controlled flame which flickers and closely resembles a wood-burning flame.

Abstract: Gas phase combustion producing lower emissions in gas turbines is stabilized in a lean pre-mixed combustor, by flow of the fuel/air mixture through a catalyst which is heated by contact with recirculated, partially reacted combustion gases.

Abstract: The method of combusting lean fuel-air mixtures comprising the steps of:a. obtaining an admixture of fuel and air, said admixture having an adiabatic flame above about 900.degree. Kelvin;b. passing least a portion of said admixture into contact with one or more mesolith combustion catalysts operating at a temperature below the adiabatic flame temperature of said admixture thereby producing reaction products of incomplete combustion; andc. passing said reaction products to a thermal reaction chamber;thereby igniting and stabilizing combustion in said thermal reaction chamber.

Abstract: Unusually strong and highly perforated plates are formed by pressurized filtration of a suspension of chopped ceramic fibers in an aqueous dispersion of colloidal alumina or colloidal silica through a mold having a perforated filter base and a pin support base having pins that extend through and beyond the perforations of the filter base. Pressurized filtration is preferably conducted by applying vacuum on the down stream side of the mold. When the layer of chopped fibers deposited on the perforated filter base has the desired thickness, filtration is stopped. The perforated filter base and pin support base are moved apart to retract the pins from contact with the perforated layer of chopped fibers which is transferred to a drier operating at a temperature not exceeding 650.degree. F., for conversion into a strong perforated plate.

Abstract: A metal body for the gas burner of an infrared radiant heater appliance, the body (1) being generally elongate in shape having an open front that receives a plate (25) for generating infrared radiation and itself being made up of two sheet metal parts (2, 3) that are cut out, stamped, folded, and assembled together. The parts comprise: a U-shaped back part (2) having an elongate main face (4) with a longitudinally elongate depression (5) shaped to form half of a tubular Venturi shape; and a dish-shaped front part (3) with an elongate bottom to the dish-shape that presents a longitudinally elongate depression (18) shaped to constitute half of a tubular Venturi, a portion of the bottom of the dish-shape situated beyond the outlet from the Venturi being cut out and folded towards the inside of the dish-shape so as to define an opening (23) through which the gas mixture passes into the dish-shape, said portion constituting a deflector (21) suitable for distributing the gas mixture inside the dish-shape.

Abstract: The method of combusting lean fuel-air mixtures comprising the steps of:a. obtaining a gaseous admixture of fuel and air, said admixture having an adiabatic flame temperature below a temperature which would result in any substantial formation of nitrogen oxides but above about 800.degree. Kelvin,b. contacting at least a portion of said admixture with a catalytic surface and producing reaction products,c. passing said reaction products to a thermal reaction chamber, thereby igniting and stabilizing combustion in said thermal reaction chamber.

Abstract: An infrared ray emitter with catalytic burner including a box having an opening covered by a catalytic structure and wherein a supply of combustion gas is applied adjacent the catalytic structure and a supply of recirculating gas is introduced into the box by a fan driven by a motor which extends exteriorly from a furnace in which the emitter is mounted. Brackets are provided to mount the box within a furnace in such a manner that the emitter may be angularly adjusted with respect to the support brackets.

Abstract: A combustion catalyst is disclosed which is composed of a durable support containing a plurality of mutually partitioned and independent combustion gas flow paths and an active catalyst formed mainly of palladium and/or palladium oxide and deposited in the form of a coating on the inner wall surfaces of the combustion gas flow paths and characterized in that the deposition of the active catalyst in the form of a coating on all the inner wall surfaces is omitted in part of the whole of the combustion gas flow paths. The mutually partitioned and independent combustion gas flow paths which are provided for the durable support jointly form an aggregate of opening parts in the pattern of gratings and these opening parts have a square, rectangular, triangular, or hexagonal cross section. Thus, the durable support constitutes a so-called honeycomb structure.

Abstract: In a gas burner device having a first burner having a first fire hole formed therein and a second burner having a second fire hole arranged therein, the fire hole is disposed around the first fire hole of a first burner to straddle the first fire hole. The second burner has a common suction hole through which a fuel gas and primary air are supplied to the second fire hole independent of fuel gas and primary air supplied to the first burner.

Abstract: A premixed gas burner has a hollow body including a closed end and an entry end into which a combustible gas and air mixture may flow. The body has a multiplicity of apertures through which the mixture may pass from the hollow interior. A burner portal deck is positioned in superposed relationship over the apertures for permitting the gas air mixture to form a controlled flame. A porous woven fabric formed from ceramic fiber having high thermal insulation properties is located above the deck and separates the deck from the flame front formed when the mixture is ignited. The fabric insulates the deck from excessive temperatures, prevents flash back, allows use of conventional stainless steel for the deck and body components and makes possible the manufacture of long burner sections. A long burner section has a number of decks in side-by-side relationship with an insulating fabric mat over the decks for not only providing insulation, but also forms a gasket between the adjacent decks.

Abstract: The present invention intends to provide a surface combustion burner which can permit high intensity combustion at the burner surface by preventing the occurrence of a lift phenomenon of flames due to whirling of air from the peripheral portion of the surface combustion burner. To this end, a mixing chamber positioned rearwardly of a porous member having its front surface constituting a combustion surface is divided by a partition wall into a first mixing chamber positioned at a central portion and a second mixing chamber positioned to surround the first mixing chamber so that fuel gas mixtures at different air ratios are supplied to the first and second mixing chambers, respectively, and/or the porous member having its front surface serving as the combustion surface has a resistance against the flow velocity of fuel gas mixture which is higher at a peripheral edge nearby region than at the remaining region.

Abstract: An atmospheric gas burner produces improved turndown by separating a small number of the burner ports for simmer service. The burner has an internal baffle which includes a cup section having four outwardly-extending channels. Each one of the channels aligns with a separate one of the ports. The burner also includes a first fuel nozzle arranged to provide fuel to all of the ports in conventional fashion and a second fuel nozzle which provides fuel to the four simmer ports only. The second fuel nozzle has an injection orifice with a smaller cross-sectional area than the injection orifice of the first fuel nozzle. Preferably, the second orifice is sized to provide the same input rate at a maximum pressure that the first orifice does at a minimum pressure. By using a small number of ports for simmer service, the gas velocity through these ports is increased and improved turndown is achieved. In another embodiment, the baffle divides each port into upper lower sections, instead of separating some of the ports.

Abstract: A gas-fired infrared radiator comprising a closed housing which includes a combustion chamber, with a side of the radiator that is to be directed towards an object being a radiation plate which forms a boundary of the combustion chamber, and comprising at least one burner, wherein the or each burner is a high-speed burner adapted for combustion in two combustion stages, with the second combustion stage taking place in the combustion chamber, the or each high-speed burner is arranged in such a manner that a flame formed by the or each high-speed burner is directed at the radiation plate, and gas guiding means are provided for partly recirculating flue gas which has been passed along the radiation plate, to the first or second combustion stage.

Abstract: Discloses a heat-insulating structure for combustion equipment of such a type that a burner element of combustion equipment is insertedly disposed at an installation opening of thermal equipment such as a boiler, with a view to simplified structure and enhanced workability. In combustion equipment (B) having a burner element (20) insertedly disposed at the installation opening (1) of the thermal equipment (A) via the support frame (30) a thermal insulator (50) flush with the burner element (20) on the thermal equipment (A) side is disposed between the installation opening (1) and the outer side face of the support frame (30).

Abstract: A self-cleaning gas-fueled oven for cooking with a flameholder and door which permit self-cleaning at temperatures exceeding 900.degree. F. The flameholder has a grille divided into two opposed, substantially flat portions, each of which contains an array of ports of two distinct sizes. The smaller-sized ports are tapered, increasing in cross-sectional area in the direction of gas flow through the grille. The oven door has a lip extending substantially perpendicularly from the door's sidewalls so as to overlap the periphery of the door's inner panel.

Abstract: Lean fuel--air mixtures having an adiabatic flame above about 900.degree. Kelvin are combusted by passing at least a portion of the admixture into contact with a mesolith combustion catalyst operating at a temperature below the adiabatic flame temperature, to produce reaction products of incomplete combustion. The incomplete combustion products are then ignited in a reaction chamber, thereby stabilizing combustion.

Abstract: An aspirated wick atomizer nozzle device having a nozzle body and a screen wire wick sandwiched between the an outlet surface of the nozzle body and the inside surface of a nozzle cap. A liquid entering the nozzle body through a fuel inlet passes by a wicking action of the screen wire wick to a fuel and air exit port where it is entrained and atomized by a gas exiting the nozzle body through an air outlet orifice.

Abstract: A gaseous fuel burner and method in which a high-firing rate (blue/non-surface radiant) zone is created between two lower firing rate (red/surface radiant) combustion zones. The method of the invention can be achieved by selective perforation of porous sintered fiber mat burner surfaces to achieve improved burner performance and relatively low NO.sub.x emissions.

Abstract: Combustion methods and burners reduce the emission of pollutants such as CO and NO.sub.2 by promoting the completion of combustion reactions by at least temporarily separating ambient air from hot products of combustion.

Abstract: A two stage, atmospherically supplied burner which produces reduced levels of NO.sub.x in applications such as residential water heaters or light commercial applications. A novel, perforated plate first stage burner is disclosed for first stage combustion. A variety of embodiments disclose various approaches to supplying atmospheric to support second stage combustion. A conventional first stage burner is also disclosed with modifications to achieve two-stage, atmospherically supplied combustion.

Abstract: In a gas-fired stove or oven, gas is burned in a porous ceramic surface combustion burner which generates selective emissive radiation in a narrow band. The high temperature surface of the burner includes a narrow band quantum emitting substance such as rare earth metal oxide. Relatively shorter wavelength radiation from this quantum emitting surface illuminates process targets having an absorption spectrum nearly matched to the emission spectrum of the burner surface, for a variety of applications such as cooking. The selected emission may be passed through a glass top stove to heat a pot with an absorptive bottom or may pass on through a glass pot to heat the food directly.

Abstract: The invention is directed to a heatable appliance, in particular a curling iron (10), including a device (18) for flameless combustion of a fuel/air mixture and an associated activation device (20, 21) for initiating the flameless combustion action, wherein the device (18) comprises a carrier means coated with a catalytically active material. According to the present invention, the carrier means is configured as a stable carrier structure (28) comprised in particular of a metal foil provided with perforations (32) or a wire lattice. At least one metal wire (36) preferably catalytically coated is arranged on the carrier structure (28) to serve as a starter catalyst (34). By this means, the activating ability of the catalytically coated carrier structure (28) is promoted.

Abstract: In a method of combustion designed to achieve a further reduction in harmful emissions, especially of NOx and CO, which is viable at advantageously reduced noise levels and lower cost with any burner of a type comprising a slotted or pierced diffuser of thin sheet metal in receipt of fully or partly mixed gas and air supplies, typically in appliances comprising a heat exchanger such as the boilers of central heating systems, the essential steps are: a) supplying a uniform flow of fuel-air mixture to the slots; b) discharging the mixture from a pierced surface of substantially doughnut geometry comprising a slotted peripheral area (Ap) and an essentially solid central area (Ac) of prescribed proportions; c) bringing combustion to completion in a slender lamellar flame; d) regulating the rate of aeration to a value between 0.9 and 1.4, or e) to values less than 1.6; f) effecting a recycle of post-combustion gases.