Abstract: In a method of operating a multi-stage combustion chamber, having at least one primary burner (110) of the premixing type of construction, the fuel injected via nozzles is intensively mixed with primary combustion air inside a premixing space in advance of the ignition. Secondary combustion air is directed into a secondary combustion space (62) which is arranged downstream of the precombustion space (61). The primary burner (110) is a flame-stabilizing double-cone burner without a mechanical flame retention baffle, which is operated at the lower stability limit. The burnt gas is accelerated between precombustion space (61) and secondary combustion space (62). For the purpose of forming a self-igniting mixture, cooling air from the double-wall combustion-chamber boundary and additional fuel are introduced into the burnt-gas flow leaving the precombustion space.

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: In the process and installation for decontaminating a liquid effluent contaminated by at least one organic substance, a gaseous combustible is burned in a reactor to produce a flame containing hydroxyl free radicals OH.degree. and oxygen O.sub.2 and that flame is centered on the geometrical axis of the reactor. A helical flow of liquid effluent is produced on the inner cylindrical wall of the reactor to cause a direct contact between the hydroxyl free radicals and the organic substance contaminating the liquid effluent. By means of the hydroxyl free radicals, the organic substance is oxidized in liquid phase. The high temperature of the flame enables completion of the oxidation of the organic substance, in liquid phase, by means of the oxygen O.sub.2 present in the flame. At the outlet of the reactor, the liquid and gaseous products are separated; the liquid product is collected while the gaseous product is evacuated.

Abstract: A burner apparatus and method for reducing nitrogen oxides that are formed during combustion of gaseous fuel. Primary gaseous fuel and excess oxidant are premixed to form a fuel/oxidant mixture which is introduced into and combusted within a primary combustion zone. Primary combustion products are introduced into a secondary combustion zone. Secondary gaseous fuel is also introduced into the secondary combustion zone and is preferably mixed with the primary combustion products. The mixture of secondary gaseous fuel and primary combustion products is combusted in a secondary combustion zone. A portion of the secondary combustion products are internally recirculated into the secondary combustion zone. The overall combustion products can be externally recirculated and introduced into the primary combustion zone. A portion of the fuel/oxidant mixture, with or without the recirculated overall combustion products, can be bypassed around the primary combustion zone and introduced into the secondary combustion zone.

Abstract: A staged oxy-fuel burner for producing a generally flat fuel rich flame overlying a highly radiative fuel lean flame, the burner having a fuel passage terminating in a nozzle, the fuel passage and nozzle having a generally elongated cross-section, a housing of complementary shape surrounding the fuel passage, so that when fuel is introduced into the fuel passage and an oxidizer is introduced into the passage defined by a space between the housing and the fuel passage a generally flat fuel rich flame is produced at the nozzle end of the fuel conduit and a staging nozzle for introducing oxidizer underneath and in a shape complementary to said fuel rich flame to produce a highly radiative fuel lean flame under said fuel rich flame.

Abstract: A method and apparatus is disclosed for controlling staged combustion systems of the type used for combusting two reactants wherein at least one reactant is supplied as two flows, the first of which is combusted with the flow of the other reactant in a primary stage and the other of which is combusted with the exhaust of the primary stage in a secondary stage. In the present invention, the respective flows are monitored and controlled to provide a desired equivalence ratio for both the first stage and for the burner overall which is adaptable in response to variable input conditions. By controlling the flows in this way, a calculated energy output or adiabatic flame temperature can be produced. The present invention can also control the reactant flows to each stage in response to measured parameters such as flame temperature or emission levels. In this way, the flows can be varied in order to drive the measured parameters to a desired level.

Abstract: A method and apparatus for controlling NO.sub.x produced by a natural gas fired combustion source includes establishing a control curve for the combustion source for indicating NO.sub.x levels based on steam injection rates and fuel flow rates provided to the burners. The atomizing steam injection flow rate provided to the burner is measured as well as the fuel flow rate. A NO.sub.x level is determined for the combustion source based on the atomizing steam injection flow rate, the firing rate, and the fuel flow rate. NO.sub.x levels are lowered by adding atomized steam to the burners according to the pre-programmed control curve.

Abstract: A combustion method is provided for carrying out combustion with reduced generation of nitrogen oxides. The combustion method involves partially combusting a fluid fuel stream with a low velocity oxidant and thereafter mixing and combusting the resulting product with a secondary oxidant stream diluted with ambient gas. The velocity of the secondary oxidant stream is either increased to reduce the nitrogen oxides emission level or adjusted to provide the desired secondary oxidant/low velocity oxidant ratio which is useful for further decreasing the formation of nitrogen oxides. Normally, increasing the ratio and/or velocity further decreases the nitrogen oxides emission level. When liquid fuel is employed, it is atomized with atomizing fluid in such a manner to produce a liquid fuel stream having a very narrow spray angle. The production of such a stream allows the burner to be operated without water cooling.

Abstract: An oxidant injector for a burner having a nozzle with a surface prescribing a continuous function enabling laminar flow of secondary oxidant over the nozzle surface which functions simultaneously to take heat off, and to prevent exothermic free radical recombinations from occurring proximate, the nozzle surface.

Abstract: An apparatus and method for burning combustible material are provided. The apparatus has a combustion chamber with an intake and an exhaust end, a means for injecting combustible material into the intake end of the chamber, a means for igniting the combustible material to generate a flame front, and a means for providing a variance in pressure in the chamber between the intake end and the ignition means, so that a flame front is held substantially stationary in the chamber adjacent the pressure variance means. In its most preferred mode, the apparatus and method may be used for burning energetic materials which, due to their highly volatile and reactive properties, present unique hazards above and beyond those encountered with less reactive non-energetic combustible materials.

Abstract: In a combustion process permitting reducing the production NO.sub.x, there is ejected via a burner (1) at least one flow of combustible gas, at least one flow of an oxygenated gas supporting combustion and at least one flow (10) of one of these gases in liquid phase. In an oxyburner, one portion (between 13 and 35%) of the oxygen is injected in liquid phase. In an aeroburner for natural gas, one portion (10 to 30%) of this latter is ejected in a coherent liquid jet. Use particularly in glass furnaces and heaters.

Abstract: In the case of a heat generator which essentially consists of a premix burner (100) and a flame tube (1), the hot gases (10) from the combustion in the premix burner (100) are fed into the flame tube (1), and there undergo staged post-combustion. This post-combustion takes place by means of a first post-combustion stage (11) and a second post-combustion stage (12). The air/fuel mixture (11a, 12a) is provided for each post-combustion stage (11, 12) in individual mixers (200, 300). These mixers are arranged axially with respect to the flame tube (1) and work in such a way that injection of the corresponding mixture (11a, 12a) makes it possible to obtain different combustion zones which extend in a staged sequence over the flame tube (1). By virtue of this staged post-combustion mode NO.sub.x emissions can be reduced by a factor of 5 compared to conventional techniques.

Abstract: An acoustically pulsating burner assembly which includes an elongated outer tube, a fuel supply means located within the tube, and utilizes one or more integral axially adjustable Sondhauss thermoacoustic tubular elements to generate pulsations within the burner. The acoustic pulsations are generated inside the axially movable closed end tube element provided within the burner, and these vibrations promote more efficient combustion of the fuel so as to reduce undesired emissions in the combustion products. If desired, multiple thermoacoustic tubular elements of different lengths can be advantageously used to generate pulsations of different frequencies within the burner assembly. The burner assembly is located in a furnace windbox, and can be adapted for combusting gas, oil or particulate fuels such as coal.

Abstract: An oxidant lancing nozzle and lancing method wherein first and second oxidant streams are injected into a combustion zone under defined conditions enabling the lancing of oxygen to augment a main combustion reaction with improved flame stability and unchanged or even reduced NO.sub.x formation.

Abstract: In a premixing burner (1) which essentially consists of a mixing section (3) and a downstream combustion section (13), an ignition zone (9) being placed intermediately between the two sections, a fuel (5) and combustion air (4) are introduced at the head side of the mixing section (3) to form a mixture. At the end of the mixing section (3), the fuel/air mixture (6) ignites in the region of the ignition zone (9), specifically in such a way that no backflow zone is formed on the axis (12) of symmetry. Self-ignition and flashback are prevented by the high velocity of the mixture (6) in the mixing section (3). A conical reaction zone (11) is produced by the temperature differences between wall boundary layer and core of the hot-gas flow (15) inside the combustion section (13).

Abstract: A nozzle and gas injection method using the nozzle wherein the nozzle comprises a section of porous material. Gas passes through one or more passageways running the length of the porous material section and also diffuses through the porous material section exiting across the nozzle face. This gas passing through the face serves to keep deleterious material, such as zone vapors, from contacting and fouling the nozzle.

Abstract: An oxy-fuel burner for producing a generally flat luminous flame, the burner having fuel passage terminating in a nozzle, the fuel passage and nozzle having a generally elongated cross-section, a housing of complementary shape surrounding the fuel passage, so that when fuel is introduced into the fuel passage and an oxidizer is introduced into the passage defined by a space between the housing and the fuel passage a generally flat luminous flame is produced at the nozzle end of the fuel conduit. A precombustor having a cross-sectional shape complementary to that of flame end of the burner can be disposed on the flame end of the burner housing to further enhance combustion and protect the burner from the furnace atmosphere.

Abstract: A burner apparatus and method for reducing nitrogen oxides that are formed during combustion of gaseous fuel. Primary gaseous fuel and excess oxidant are premixed to form a fuel/oxidant mixture which is introduced into and combusted within a primary combustion zone. Primary combustion products are introduced into a secondary combustion zone. Secondary gaseous fuel is also introduced into the secondary combustion zone and is preferably mixed with the primary combustion products. The mixture of secondary gaseous fuel and primary combustion products is combusted in a secondary combustion zone. A portion of the secondary combustion products are internally recirculated into the secondary combustion zone. The overall combustion products can be externally recirculated and introduced into the primary combustion zone. A portion of the fuel/oxidant mixture, with or without the recirculated overall combustion products, can be bypassed around the primary combustion zone and introduced into the secondary combustion zone.

Abstract: A method and apparatus for combustion of a liquid fuel and oxygen which produces a fishtail or fan-shaped flame configuration.

Abstract: A burner apparatus for the combustion of a fuel and an oxidizer includes a burner block having a fuel line for feeding fuel to a fuel port opening into a combustion chamber and a plurality of primary and secondary oxidizer lines positioned around the fuel line for feeding an oxidizer to a primary and secondary oxidizer port to the combustion chamber for combustion with the fuel from the fuel port. The primary and secondary oxidizer lines and ports are spaced around the fuel port so that controlling the oxidizer is used to change the position and shape of the flame in the combustion chamber. First and second oxidizer valves are located in the oxidizer feed lines and vary the amount of oxidizer fed through the oxidizer line so that the first and second oxidizer control valves for each set of oxidizer lines are spaced around the fuel port to allow both the position and the shape of the burner flame to be controlled.

Abstract: Method and apparatus for generating oxy-liquid fuel with lowered NO.sub.x products using low pressure oxygen to atomize liquid fuel and produce an oxy-liquid fuel flame and surrounding the oxy-liquid fuel flame by an oxidizer, confining the oxy-liquid fuel flame and oxidizer in a precombustor for a distance determined by the rate of flame propagation and the diameter of the pre-combustor.

Abstract: A gas barbecue grill has a housing, a grate supported by the housing for supporting food for cooking, and a gas burner for supplying heat. The gas burner includes at least one fluidic burner element centrally located and projecting a heating flame aligned substantially along the centerline and downward. A heat distribution member having an axis aligned with the centerline has at least a pair of downwardly diverging planar elements with the burner projecting a flame along the centerline which heats the center of the distribution member. The heat distribution member has first and second groups of apertures, the first group of apertures being proximate one end of the heat distribution member and spaced from the center of each of said planar elements. A second group of apertures formed proximate the end of heat distribution member opposite the burner end and spaced from the center of the distribution member and in each of the planar elements.

Abstract: A method and apparatus for injecting fuel and oxidant into a combustion burner. At an exit plane of a nozzle, fuel is discharged in a generally planar fuel layer which has an upper boundary and a lower boundary. Also at the exit plane, oxidant is preferably discharged in both a top layer along the upper boundary of the fuel layer and a bottom layer along the lower boundary of the fuel layer. In a downstream flow direction, the fuel and oxidant preferably converge in a generally vertical plane and diverge in a generally horizontal plane. The discharged fuel and oxidant form a fishtail or fan-shaped flame configuration. A refractory manifold can be used to further enhance the fishtail or fan-shaped flame configuration.

Abstract: Method and apparatus for safely combusting a fuel in such manner that very low levels of NO.sub.x and CO are produced. The apparatus comprises an inlet line (12) containing a fuel and an inlet line (18) containing an oxidant. Coupled to the fuel line (12) and to the oxidant line (18) is a mixing means (11,29,33,40) for thoroughly mixing the fuel and the oxidant without combusting them. Coupled to the mixing means (11,29,33,40) is a means for injecting the mixed fuel and oxidant, in the form of a large-scale fluid dynamic structure (8), into a combustion region (2). Coupled to the combustion region (2) is a means (1,29,33) for producing a periodic flow field within the combustion region (2) to mix the fuel and the oxidant with ambient gases in order to lower the temperature of combustion. The means for producing a periodic flow field can be a pulse combustor (1), a rotating band (29), or a rotating cylinder (33) within an acoustic chamber (32) positioned upstream or downstream of the region (2) of combustion.

Abstract: A supersonic flame jet device includes a body having an entry portion of relatively small cross-sectional area, an expanding supersonic nozzle section and a cylindrical duct of extended length connected in series with each other. In using the device, an oxidant at high pressure is introduced into the entry passage wherein the flow is increased to sonic velocity. The sonic velocity flow of oxidant is then introduced into the passage of expanding cross-section in the direction of the gas flow while introducing a fuel to be burned into the flow of the oxidant. The velocity of flow of the oxidant or the oxidant and the fuel is then increased to supersonic velocity prior to entry into the extended duct of constant cross-sectional area where a shock is produced to stabilize flame reactions along the extended duct length whereby a supersonic flame jet will exit the extended duct.

Abstract: A process for combustion in an industrial furnace (1), using at least one burner (2; 3) supplied with combustible (4) and combustion supporting (5) fluids. The flow rate of at least one of the fluids is pulsed at a frequency comprised between 0.1 and 3 Hz. There is provided in the furnace (1) at least one pair of two burners (2A, 2B; 3A, 3B) disposed substantially confronting each other; and the fluid of the burners of a pair is pulsed in offset phase from one burner to the other. The frequency of pulsation is between 0.1 and 1 Hz. The flow rates of fluids are substantially identical for each burner (2A, 2B; 3A, 3B) of the pair. The power of the pair of burners is greater than 300 KW.

Abstract: A burner assembly combines air and fuel to produce a burn firing into a downstream tube. The assembly includes a funnel formed to include an inlet, an outlet, and an air and fuel mixing region therebetween. The funnel also includes a cylindrical intake end at the inlet and a conical side wall mating with the cylindrical intake end and converging from the cylindrical intake end toward the outlet to fire a burn initiated in the mixing region into a tube coupled to the outlet of the funnel. The assembly also includes a system for supplying a gaseous fuel to the mixing region in the funnel and a system for introducing combustion air into the mixing region through the inlet of the funnel. The combustion air mixes with the gaseous fuel in the mixing region to produce a combustible mixture.

Abstract: This invention relates to fuel nozzles of the type that employ an entrainment fuel nozzle for initial, partial premixing of gaseous fuel and air. Such structures of this type, generally, use the gas jet to entrain surrounding air so that the fuel is somewhat diluted prior to injection into the combustor.

Abstract: A process for burning fuel includes the following steps: burning a fuel; putting an inner shell formed in a course of soot formation into contact with other components in a combustion gas to promote a chemical reaction of the other components in the combustion gas prior to the formation of an outer shell; and at the same time, inhibiting the formation of the outer shell around the inner shell. By this process, the discharged NO.sub.x gas is reduced and the amount of discharged soot is decreased.

Abstract: A burning process comprising the steps of emulsifying fuel oil with water and aerating the emulsion in a mixing tank until there is a substantial reduction of its density. The emulsion is then stabilized in a resting tank under adequate temperature and pressure conditions for maintaining an deaerating the emulsion. The stabilized emulsion is conducted to a burner nozzle where it is pulverized into particles by means of abrupt decompression in an environment poor of air.

Abstract: A burning method provides a versatile burner by promoting rapid mixing and a stable flame to reduce NO.sub.x and CO emissions over a wide operating range. The burner includes a primary fuel supply, a combustion air supply arranged to supply combustion air at low pressure, and a swirler for swirling the combustion air. When the primary fuel supply is gaseous fuel, the gaseous fuel is introduced axially into the swirling combustion air. Secondary gas nozzles are arranged at the exit of the burner to supply and mix boost gas for combustion with the combustion air when the gaseous fuel is the primary fuel supply. An atomizer is arranged for atomizing liquid fuel when the primary fuel supply is a liquid fuel.

Abstract: A method and system for Very Low Temperature Ashing (VLTA). In one embodiment, there is provided a method of ashing solid fuel or combusted or partly combusted fuel or any organic and inorganic matrix which contains minerals in a furnace with a partial pressure less than atmospheric pressure including the step of mixing of oxygen and helium with a total pressure less than the atmospheric pressure and producing a plasma in which the mineral components in the samples are not being affected essentially, wherein the proportion of the gas mixture achieve a surface temperature not exceeding 150.degree. C. on the sample. In an alternative embodiment, there is provided a method of ashing solid fuel or combusted or partly combusted fuel or any organic and inorganic matrix which contains minerals in a surface with a plasma including the step of regulating the proportion between oxygen and helium by a reduction of oxygen content, wherein the surface temperature shall not exceed 150.degree. C.

Abstract: A burner (1) is provided, comprising a primary mixture supply conduit (2) and a primary mixture chamber (6) connected with the supply conduit (2), the primary mixture chamber (6) having primary discharge openings (7) for discharging burning mixture into the space surrounding the burner (1). The burner (1), which may be made of a ceramic material, which may be made of a ceramic material, further comprises flame stabilizing means arranged near the primary discharge openings (7). The flame stabilizing means may be vortex strips (14) separating areas (16) of discharge openings (7), or they may be secondary discharge openings (5), discharging burning mixture from a secondary mixture chamber (3) near the primary discharge openings (7).

Abstract: An improved gas burner comprising a gas nozzle having a first flame stabilizer mounted to the front end thereof and a plurality of gas blow apertures arranged circumferentially therein adjacent to the first flame stabilizer, a second flame stabilizer having a plurality of secondary combustion air passages arranged in the circumferential end thereof and a primary combustion air passage arranged in the center thereof which is defined by the outer surface of the gas nozzle, and a burner cone accommodating the second flame stabilizer coupled to the inner wall thereof, said gas burner being improved for reducing unwanted nitrogen oxide and/or uncombusted gas, characterized in the positional relation between the flame stabilizer(s) and the gas blow apertures, the novel construction in which the shape of the flame stabilizer is designed for optimum function with association with its positional relation, the novel arrangement in which the flame stabilizer can be controlled for optimum positioning, and the improved bu

Abstract: In a gas-operated premixing burner for the combustion chamber of a gas turbine, the fuel injected within a premixing space (21) by means of a plurality of nozzles (17) is intensively mixed with the combustion air prior to ignition. The nozzles are arranged around a burner axis (10). In order to influence the fuel profile at outlet from the burner in a specific manner, the fuel concentration in the region of the burner axis is kept greater than the average fuel concentration at the burner outlet plane (22). For this purpose, additional burner nozzles (23) are provided in the region of the burner axis (10). The additional burner nozzles (23) can be supplied via a separate fuel conduit (24).

Abstract: An apparatus and method are provided for reducing NO.sub.x production during combustion in an tangential burner. Air nozzles are arranged tangentially to a fuel/air nozzle and are tilted relative to the fuel air nozzle. Upon operation, spaces are formed between the air flow and the fuel flow which entrain laterally combustion gases thereby delaying mixing of the air and fuel flows. By this delay, NO.sub.x production is reduced.

Abstract: A multi-stage combustion apparatus and method for use with externally fired power plants that allows the temperature of the heat released at any stage to be matched to the thermal characteristics of the working fluid from the power plant.

Abstract: A burner configuration includes approximately concentrically disposed annular conduits for delivering various operating media. A plurality of outlet nozzles admix a gaseous medium or a liquid medium in finely distributed form with an air flow flowing in an approximately conically tapering outer annular-conduit air delivery system. A further annular conduit on an inflow side discharges into the annular-conduit air delivery system above the outlet nozzles.

Abstract: A combustion method wherein high velocity fuel is injected into a cavity recessed from a furnace zone for flow into the furnace zone, low velocity oxidant fluid is injected into the cavity for coaxial flow with the fuel, and the resulting combusting fuel and oxygen has imparted to it an angular component by operation of swirling oxygen flow and/or outwardly angled fuel flow, enabling control of the high velocity flame length.

Abstract: A low NOx gas burner for heating objects having a supply of gas under pressure which is to be mixed to achieve a combustible mixture, gas flow line connecting to said burner to said supply, a burner means for mixing air with said fluid fuel to achieve said combustible mixture, characterized by said burner means includes one or more jet forming means for issuing one or more jets of said gas having a given cross-sectional area and sweeping said one or more jets of gas in ambient air downstream of said burner means to mix air with said gas and achieve said combustible mixture a distance spaced from any physical structure of said burner means whereby a flame front of burning combustible mixture has a broad shape and is spaced a predetermined distance from said burner.

Abstract: A ceramic burner for a hot blast stove has a central gas duct that opens into the central zone of a burner crown and side air ducts on both sides of the gas duct which also open into the central zone. To improve combustion characteristics, there is a central air duct in the gas duct opening out within it. Air is supplied to the central air duct in an upward flow which exits in two opposing directions through side openings.

Abstract: The invention provides a method and apparatus for creating a stable combustion flame from natural gas and an oxygen containing gas which is useful for the pyrometallurgical treatment of finely divided materials such as metal ores. In particular, natural gas and the oxygen containing gas are injected in a manner which forms recirculation zones between the natural gas and oxygen containing gas thereby maintaining the stability of the combustion flame. The apparatus of the invention encourages the formation of the recirculation zones by using a bluff body orifice plate to provide a dead space between the injections of the oxygen containing gas and natural gas. Additional gas injection is used downstream in the combustor to create turbulence and further stabilize the combustion flame.

Abstract: An improved premixed gaseous fuel burner for a metal processing furnace includes an axially adjustable gas supply tube concentrically positioned within the burner body for delivering a flow of oxidant or other gaseous fuel component to the combustion chamber of the furnace. Axial repositioning of the air tube controls the spread of oxidant at the core of the flame, thereby controlling flame temperature and the operating environment of the combustion chamber and furnace. A flow mixer having a pair of helically arranged vanes provided in the annular space between the supply tube and the burner body imparts turbulent swirl to the premixture flow to cause enhanced mixing of the premixture. The gas supply tube is externally adjustable and includes a peep sight for externally viewing the flame in the furnace.

Abstract: A burner system and combustion method for high temperature applications employing a high velocity central fuel stream and a low velocity annular coaxial oxidant stream to carry out stable steady combustion in an expanding combusting stream within a cavity stably attached to the fuel nozzle so as to prevent combustion zone furnace gases from entering the cavity.

Abstract: A method of low-NOx combustion and a burner device for effecting the same, in which a primary fuel is injected in a direction from the periphery of stream of a combustion air towards that same combustion air, effecting a first combustion, so as to create a generally cylindrical primary flame covering the combustion air, whereby a secondary fuel injected towards the combustion air is shielded or intercepted by such primary flame from the combustion air, while causing NOx in the primary flame to be reduced by the secondary fuel, after which, a second combustion is effected by bringing the secondary fuel to contact with a portion of the combustion air penetrating through the primary flame, at a downstream side. This arrangement permits more positive decrease of NOx density in an exhaust gas.

Abstract: A burner assembly combines air and fuel to produce a burn firing into a downstream tube. The assembly includes a funnel formed to include an inlet, an outlet, and an air and fuel mixing region therebetween. The funnel also includes a cylindrical intake end at the inlet and a conical side wall mating with the cylindrical intake end and converging from the cylindrical intake end toward the outlet to fire a burn initiated in the mixing region into a tube coupled to the outlet of the funnel. The assembly also includes a system for supplying a gaseous fuel to the mixing region in the funnel and a system for introducing combustion air into the mixing region through the inlet of the funnel. The combustion air mixes with the gaseous fuel in the mixing region to produce a combustible mixture.

Abstract: A combustion method which employs highly fuel-rich combustion and highly fuel-lean combustion separately and simultaneously within a combustion zone followed by intermixture of their resulting gases within the combustion zone for further combustion.

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.

Abstract: A heating devices for complete intermixing of gaseous fuel and air to allow complete combustion of the gas and air mixture in a mushroom shaped flame. The device includes an element for supplying an axial flow of air and a swirling device in fluid communication with the air supply to turbulently swirl and radially inward direct the air entering from the air supply. The heating device also includes an nozzle element located within a mixing chamber formed by the swirling device. The nozzle forms a plurality of bores to emit the fuel as generally radially outward directed streams into the swirling stream of air exiting from the swirling device to intermixes the fuel and air. A disk connected to the nozzle restrains the gas streams within the mixing chamber to facilitate the mixing of the fuel and air. The intermixed fuel and air is then ignited by an ignition device. A combustion chamber is disposed about an upper first end of the swirling device to contain the generated flame.

Abstract: In a double-cone burner, at least one row of nozzles (10) for a gaseous fuel containing highly reactive components and having a medium calorific value are arranged on the periphery of the partial conical bodies (1, 2) of the burner near the burner outlet at a distance of approximately 30% of the nominal burner diameter. In addition, there is a fuel conduit (11) and a distributing passage (17), placed in the region of the nozzles (10), for the highly reactive fuel. The gaseous fuel (15) containing highly reactive components is injected at high velocity through the nozzles (10), which have a diameter which is smaller than 1% of the nominal burner diameter, into the zones of high air velocity and the penetration depth and the direction of the fuel jets are matched to one another in such a way that ignition only takes place behind the burner, after mixing has occurred.