Abstract: A process and apparatus for oxygen-rich combustion wherein a first portion of about 5 to about 40 percent of the total fuel to be cracked and combusted is introduced to a cracking chamber where it is combusted and cracked at a temperature below about 2200.degree. C. to produce a cracked products mixture. Oxygen-rich gas of greater than about 30 volume percent oxygen is introduced to the cracking chamber in about 5 to about 50 percent of the stoichiometric requirement for complete combustion of the first portion of fuel introduced to that chamber. Cracked products mixture, a second remaining portion of fresh fuel and oxidizer having sufficient oxygen for substantially complete combustion of the combustible portion of the cracked products mixture and the fresh fuel is introduced to a combustion chamber wherein the combustible portion of the cracked products mixture and the fresh fuel is combusted.

Abstract: A method for reducing the NO.sub.x content of effluent gas in a coal-dust-fired combustion system comprising establishing at least two vertically adjacent burner planes, in which the burner flame cores are fed with primary air in the core zones in a substoichiometric ratio to the coal dust feed stream and are additionally fed with secondary air comprising recycled flue gas in optional combination with preheated fresh air, and in which the burner mantle zones are fed with tertiary air comprising recycle flue gas and optional fresh air, so that, overall, a substantially stoichiometric combustion air ratio is established in the region of the lower burner plane and, overall, a highly substoichiometric combustion air ratio is established in the region of the upper burner plane. The apparatus employed is an economical primary measure requiring little space and minimal loss of energy, and is easily retrofitted in existing plants.

Abstract: A process and apparatus for the nitric oxide-free reaction of liquid and gaseous fuels with heat in heat generators in a plurality of stages. The reaction is carried out in four successive stages, permitting the combustion of a portion of the fuel with a portion of the combustion air in a cooled annular chamber with a stoichiometric or overstoichiometric ratio. The remaining amount of fuel is mixed in a mixing unit connected downstream. The resulting mixture is catalytically reacted to fission or fuel gas with downstream cooling of the fission gas in a heat exchanger. The fission gas so formed is burned in one part of the cooled annular chamber of the second stage. On mixing of the burned combustion gas with the remainder of the fission gas in the catalyst, downstream cooling of the slightly overstoichiometric flue gas so formed is carried out in a heat exchanger.

Abstract: A method for burning a fuel, containing chemically bound nitrogen, in a two-stage, rich-lean combustion process, including; introducing the fuel and at least one stream of primary air into a primary combustion region at a fuel-air ratio above the stoichiometric ratio and in a manner to intimately mix the fuel and air and establish a stabilized flame adjacent the upstream end of the primary combustion region, maintaining the flame in the primary combustion region for a period of time sufficient to produce a combustion product mixture containing less than a predetermined amount of NO.sub.x pollutants and abruptly terminating the primary combustion region while introducing at least one stream of secondary air into the secondary region in an amount sufficient to reduce the overall fuel-air ratio below the stoichiometric ratio and in a manner to prevent backflow of the secondary air into the primary combustion region.

Abstract: Device for improving the heating of a channel (2) for distribution of glass (1), said device including a cylindrical duct (6) connected at its upstream end to means (7) for feeding a premixture of air and fuel gas and whose downstream end (8) opens inside a cylindrical bore (9) in a refractory block (10) inserted in a wall (11) of the channel, said cylindrical bore (9) extending by means of a coaxial cylindrical duct (12), of smaller diameter than that of said bore, the cylindrical channel (6) being surrounded by a sealing ring (13) which covers the face of the cylindrical bore (9) in which said channel (6) is inserted.

Abstract: A burner and method enabling operation of a post-mixed burner having radially spaced fuel and main oxidant injection points with a stable flame without the need of a separate oxidant annulus proximate the fuel stream characterized by defined relationships enabling passing stabilizing oxidant from the main oxidant stream into the fuel stream upstream of their injection into the combustion zone wherein the stabilizing oxidant velocity decreases from that of the main oxidant and the stabilizing oxidant passage flow area increases at the fuel stream communication with respect to an upstream restriction.

Abstract: A process for thermally converting components of gas currents contaminating the environment and equipment for performing the process. Combustion serving for the primary heat production is performed in the gas current to be converted thermically and in a plurality of places in proper distribution. In such a manner, gas currents next to the flames produced in the course of combustion are heated to high temperatures and by utilizing the secondary heat quantity arising in the course of the thermic conversion taking place quickly in the vicinity of the flames, the process of thermal conversion is further accelerated.

Abstract: A pulverized fuel firing apparatus comprises a first pulverized fuel injection compartment so constructed that the combined amount of primary air and secondary air to be consumed is less than the theoretical amount of air required for the combustion of the pulverized fuel to be fed as mixed with the primary air to a furnace, a second pulverized fuel injection compartment so constructed that the combined primary and secondary air amount is substantially equal to the theoretical air for the pulverized fuel to be fed together with the primary air, and a supplementary air compartment for injecting supplementary air into the furnace. The three compartments are arranged close to one another and control the NOx production upon combustion of the pulverized fuel.

Abstract: A method of reducing the NO.sub.x content in combustion gases by introducing secondary fuel, via a liquid carrier, into the combustion chamber at a location disposed between the supply of fuel and air for the primary combustion, and the supply of secondary air for the complete combustion.

Abstract: Method and apparatus for high temperature heating, melting, refining and superheating of materials, such a steel scrap, metals, ceramics or glass. The invention provides an economizing method of hydrocarbon fluid fuel combustion in an ongoing flame in a liquid cooled combustion chamber by separately supplying streams of fuel and at least two oxidizing gases wherein a first oxidizing gas reacts with the fuel, and a second oxidizing gas is directed about the flame core to further react with the fuel, while controlling the flow of the fuel, the oxidizing gases and cooling liquid to provide the required heat input, combustion product chemistry, temperature, velocity, emissivity and combustion block temperature. Also disclosed are burners for carrying out the invention.

Abstract: A method of spraying additives, in an intensively mixing manner, into a combustion chamber for binding sulfur during the combustion of fuels which contain sulfur. The method includes the steps of spraying the respectively utilized additive into the combustion chamber with at least one spray nozzle at an impulse which is sufficient to intensively mix the additive with the combustion gases, and of spraying the additive into those regions of the combustion chamber which have temperatures in the optimum effective range of the additive for binding the sulfur, yet in which the mixing energy of the combustion gases does not alone ensure a sufficient mixing of the additive.

Abstract: The invention relates to an improved premix burner and a method of its operation for combustion with a minimum of NO.sub.x emissions. The improvement is achieved by combining staged combustion with a premix burner in a manner such that mixing of the secondary air with the flame is delayed.

Abstract: A combustion control method wherein manipulated variables or the amounts of fuel and air in at least one combustion zone of a boiler are regulated so that both the amount of nitrogen oxides and the amount of unburned coal in the ash at an outlet of a burner furnace or at least one of them passes the regulation standards and satisfies the requirements for operating a plant.

Abstract: Method and apparatus for high temperature heating, melting, refining and superheating of materials, such as steel scrap, metals, ceramics or glass. The invention provides an economizing method of hydrocarbon fluid fuel combustion in an ongoing flame in a liquid cooled combustion chamber by separately supplying streams of fuel and at least two oxidizing gases wherein a first oxidizing gas reacts with the fuel, and a second oxidizing gas is directed about the flame core to further react with the fuel, while controlling the flow of the fuel, the oxidizing gases and cooling liquid to provide the required heat input, combustion product chemistry, temperature, velocity, emissivity and combustion block temperature. Also disclosed are burners for carrying out the invention.

Abstract: A method and burner tip for suppressing the production of oxides of nitrogen when burning a fuel in a combustion chamber containing a flame zone are described. The burner tip comprises at least one port for introducing fuel into the combustion zone and at least one port for introducing a control gas into the combustion zone, where both the fuel and control gas are introduced substantially perpendicular to the direction of introduction of combustion gas into the combustion zone. The ports are laterally spaced apart from each other. The control gas is used for controlled localized quenching of the flame zone and/or for controlled atomization of the fuel in the case of the liquid fuel to reduce the emissions of nitrogen oxides (NOx). By proper selection of the size and location of the fuel and control gas ports, and the quantity and velocity of the fuel and control gas introduced into the combustion zone, a stable flame with minimal emission of oxides of nitrogen can be obtained.

Abstract: A method and apparatus for combustion of hydrogen to produce heat, for example to generate steam for power generation. Water is electrolyzed and the hydrogen and a fraction of the oxygen products of electrolysis are passed immediately to a first combustion zone where the immediate combustion of the oxygen products and a function of the hydrogen products is effected. The products from this first combustion zone are immediately passed to a second combustion zone where combustion is again effected with the remaining fraction of the oxygen products of the electrolysis and the remaining hydrogen products from the first combustion zone. The heat generated is thereafter applied to the desired use, for example by passing the products of combustion from the second combustion zone through water to boil the water, the steam thereby produced being used for power generation. Apparatus to carry out this method is also described.

Abstract: A method and apparatus for combusting solid fuel by introducing a mixture of fuel particles and carrier fluid into a reaction chamber near the center of one end of a combustion chamber and injecting oxidizer gas tangentially into the chamber to establish a swirling flow of gas, fuel particles, and combustion products within a region adjacent the chamber walls. The mass flow rates of oxidizer gas and fuel are regulated to maintain a relatively oxygen-rich stoichiometry within an annular region and a relatively fuel-rich stoichiometry within a central region, and to cause flow of the oxidizer gas and combustion products thru the reaction chamber with throughput residence times of the order of a few hundred milliseconds. This combination of a fuel-rich core portion and a relatively oxygen-rich annular zone effects oxidation of most of the carbon content of the fuel before it reaches the walls and avoids reduction of metal compounds in the fuel, all without overall excess-air combustion.

Abstract: To allow liquid and/or gaseous fuels to be burned with decreased NO.sub.x formation, the combustion air is fed in at axial intervals one after the other. The percentage of primary air is higher than that of secondary air. The injector effect of the primary air draws flue gas out of the firebox and supplies it to a flame-initiation point between the primary-air and secondary-air feeds.

Abstract: The process and the equipment for reducing emissions of pollutants in flue gases from furnace installations (1, 6) comprises a first furnace installation (1) operated with an air excess of, for example, 15%, and a second furnace installation (6) in which afterburning within the stoichiometric range is carried out, with consumption of the residual oxygen. The flue gases leaving the second furnace installation (6) no longer contain any free oxygen, but contain unburned hydrocarbons, carbon monoxide, nitrogen oxides, sulphur dioxide and sulphur trioxide as pollutants. The first-mentioned pollutants--unburned hydrocarbons, carbon monoxide and nitrogen oxides--are converted on a multi-functional catalyst into carbon dioxide, water vapor and nitrogen. The sulphur of the flue gas is oxidized by means of an oxidation catalyst (12) to sulphur trioxide which reacts with the water vapor contained in the flue gas to give sulphuric acid.

Abstract: A burner for combustion of nitrogen-containing fuels. The burner includes a core-air tube with centrally arranged oil atomizing lance, a dust tube surrounding the core-air tube, a mantle-air tube which surrounds the dust tube and is provided with an axially shiftable twist-blade ring arranged at the air inlet, as well as a burner opening which expands conically toward the combustion chamber. The core-air tube and the mantle-air tube are supplied from a main air conduit. Air jets or nozzles are provided in a concentric arrangement around the burner opening. These air nozzles are connected with the main air passage by conduits, and the air stream discharging from the air nozzles is regulated by a flap.

Abstract: Process and apparatus for firing a furnace using oxygen or oxygen-enriched air as the oxidant gas, comprising injection into the furnace of a plurality of oxidant jets, through nozzles, in a spaced relationship to a fuel jet, at a velocity sufficient to cause aspiration of furnace gases into the oxidant jets before the latter mix with the fuel jet, in amounts sufficient to lower flame temperature.

Abstract: A method of burning a fuel gas in a low NO.sub.x level in the exhaust gas is disclosed, wherein a radiant tube burner having concentrically arranged outer air flow nozzle, fuel gas nozzles arranged in a circle and inner air flow nozzle and having a particular structure is used and the fuel gas is burnt under a particularly limited condition.

Abstract: A method of controlling combustion in a furnace of a boiler or the like having a burner for a main combustion and a burner for a reducing combustion in order to effect combustion for furnace denitrification. The method comprises the steps of: estimating the NO.sub.x generation amount from data on a flame formed by the main combustion; estimating the reducing agent generation amount from data on a flame formed by the reducing combustion; and controlling the flow rates of fuel and air supplied for the main and reducing combustions so that the amount of NO.sub.x emission as the difference between the NO.sub.x generation amount and the reducing agent generation amount is below a specified value. In practice, each of the NO.sub.x generation amount and the reducing agent generation amount is estimated from the flame pattern, the flame volume, the distance between the outlet of the burner concerned and the root of the flame concerned, etc.

Abstract: An improved process for disposal of chemically bound nitrogen in industrial waste streams is provided wherein a effluent stream containing chemically bound nitrogen, such as ammonia stream, is contacted with an effective amount of oxygen containing gas and a stoichiometric excess of a hydrocarbon, based on the total amount of available oxygen, at a temperature greater than about 2000.degree. F. or less than 3000.degree. F., to provide a combustion effluent. The combustion effluent is thereafter contacted with an effective amount of a gaseous stream containing less oxygen than that which supports flame propagation at a temperature in the range of from about 1600.degree. F. to about 1800.degree. F., to substantially oxidize all combustibles present in the combustion effluent and provide an oxidation effluent substantially free of oxides of nitrogen (NO.sub.x) and combustibles.

Abstract: A method and apparatus for combustion of a sulfur-containing fuel which substantially reduces the amount of gaseous sulfur compounds which would otherwise be emitted.A source of oxygen, a sulfur-containing fuel, and an inorganic alkaline absorbent are reacted under controlled conditions of temperature, stoichiometry, and residence time whereby the inorganic alkaline absorbent reacts with the fuel sulfur to form a mixture of combustion products and desired solid sulfur compounds, the latter being readily removed utilizing conventional filtration equipment. In a preferred embodiment of the invention, the mixture of fuel and combustion products is passed into a nitrogenous compound destruction zone wherein, under controlled conditions, the concentration of nitrogenous compounds present are reduced to a desired level.

Abstract: To minimize NO.sub.x emissions in an intermediate size industrial boiler furnace having two vertically spaced rows of burners, each upper burner has a central fuel nozzle and a main air opening adjacent to the nozzle and communicating with a wind box associated with the furnace. In addition, each upper burner has a plurality of air delivery ports through the wall surrounding said upper burner, such air delivery ports also communicating with the wind box. The air delivery ports can be of different sizes and shapes and can be at different angles with respect to the vertical plane of the wall through which the air delivery ports extend. Control of the air through the main air opening adjacent to the nozzle of each upper burner is achieved by one or more shiftable registers or dampers which operate to close the air flow from the wind box to the air opening.

Abstract: A combustion apparatus for burning liquid fuels has a burner for atomizing and burning the liquid fuels. Oxygen enriched air, obtained by passing normal air through an oxygen permselective membrane, is supplied to the burner as air for combustion.

Abstract: A method and burner tip for suppressing the production of oxides of nitrogen when burning a fuel in a combustion chamber containing a flame zone are described. The burner tip comprises at least one port for introducing fuel into the combustion zone and at least one port for introducing a control gas into the combustion zone, where both the fuel and control gas are introduced substantially perpendicular to the direction of introduction of combustion gas into the combustion zone. The ports are laterally spaced apart from each other. The control gas is used for controlled localized quenching of the flame zone and/or for controlled atomization of the fuel in the case of a liquid fuel to reduce the emissions of nitrogen oxides (NOx). By proper selection of the size and location of the fuel and control gas ports, and the quantity and velocity of the fuel and control gas introduced into the combustion zone, a stable flame with minimal emission of oxides of nitrogen can be obtained.

Abstract: A low NO.sub.x burner for a furnace and a method of operating the burner involving a primary and secondary combustion zone wherein staged fuel and air to both combustion zones is provided. By injection of from about 40 to 60% of the liquid or gaseous hydrocarbon fuel along with about 90% of the total air required to a first reaction zone and injection of the remaining fuel with the remaining 10% of the air to a secondary reaction zone the formation of NO.sub.x is significantly suppressed. Such a burner is useful in minimizing NO.sub.x emissions for a variety of furnace types including both natural draft and forced draft furnaces.

Abstract: NO.sub.x emissions are reduced in the combustion of fuels by carrying out the combustion in at least four serially connected combustion zones, including at least three fuel-rich zones followed by a fuel-lean zone. In accordance with another aspect of the present invention, SO.sub.x emissions are reduced in the burning of a normally solid fuel, containing significant amounts of SO.sub.x precursors, by adding a sulfur scavenger to the fuel and thereafter burning the fuel in at least four serially connected combustion zones, including at least three fuel-rich zones followed by a last fuel-lean zone, and carrying out the combustion of the fuel in at least four combustion zones.

Abstract: NO.sub.x emissions are reduced in the combustion of a fuel, containing significant amounts of NO.sub.x precursors, by carrying out the combustion in at least three, serially connected combustion zones in open communication with one another, including at least two fuel-rich zones and a last fuel-lean zone and in the presence of a combustion catalyst added to the fuel adjacent the upstream end of the first of the fuel-rich zones. SO.sub.x emissions are also reduced when burning a fuel, containing significant amounts of SO.sub.x precursors, by additionally adding a sulfur scavenger to the fuel adjacent the upstream end of the first fuel-rich zone.

Abstract: The present invention relates to the recovery of heat values, including sensible heat and/or combustion heat, from vitiated gaseous mixtures containing oxygen and/or combustibles together with inert diluents in which a supplemental fuel is burned, in a combustion zone or the first stage of a two-stage, rich-lean combustion zone, the vitiated gaseous mixture is mixed with the combustion products at the downstream end of the combustion zone or the first stage of the two-stage combustion zone, as the case may be, and the effluent of the combustion is passed to a heat utiization zone.

Abstract: Nitrogen oxide emissions from burning a gas containing essentially no nitrogen such as natural gas are reduced by burning the gas simultaneously with an alcohol such as methanol.

Abstract: A method an apparatus for combustion with a minimum of NOx emission in various industrial furnaces and boilers. By injecting air for combustion into a furnace through the burner tile or air baffle in the deviated flow pattern asymmetrical with respect to the burner tile or baffle axis, the quick mixing of the air and fuel in early stages of combustion is suppressed to provide for a relatively gentle combustion and allow the burnt gas self-circulation to take place effectively, thereby minimizing the emission of nitrogen oxides.

Abstract: A method for substantially reducing emissions of nitrogenous compounds such as NO.sub.x formed during fuel combustion. The fuel is combusted with an oxygen-containing gas in an amount from about 45 to 75% of the total stoichiometric amount of oxygen required for complete combustion of the fuel. The resulting mixture of fuel and combustion products, including NO.sub.x, is maintained at a temperature of at least 1800.degree. K. for a time sufficient to reduce the NO.sub.x content of the mixture to a desired level. Thereafter, combustion may be completed in one or more additional zones at a temperature within the range of about 1600.degree. to 2000.degree. K. Alternatively, the mixture of combustion products and fuel having a reduced NO.sub.x content may be used for other applications without further combustion. For certain embodiments of the invention, various particulates may be added to the combustion zone so as to enhance the rate at which the NO.sub.x is destroyed.

Abstract: A method for minimizing the amount of nitrogen oxide pollutants produced in a process for firing a furnace using oxygen or an oxygen-enriched gas as the oxidant, in which furnace gases are aspirated into the oxidant jet prior to combustion and in which the furnace is operated using alternating low firing rate and high firing rate periods, by delaying the injection of oxidant at the high rate at the start of the high firing rate period.

Abstract: Disclosed is a process for combusting coal containing more than 1 wt. % sulfur which process comprises (a) providing a coal containing more than 1 wt. % sulfur and containing an organically bound calcium to sulfur ratio of at least about 0.8 to 1, (b) burning the coal to about 80% to 95% carbon conversion at temperatures greater than about 1,100.degree. C. in a first combustion zone in the presence of an oxidizing agent but under reducing conditions such that the equivalence ratio of coal to oxidizing agent is less than 1.5 but greater than or equal to 1.0, (c) separating the resulting solid effluent from the gaseous effluent from the first combustion zone, and (d) burning the gaseous effluent at a temperature from about 1,000.degree. C. to about 1,500.degree. C. in a second combustion zone under oxidizing conditions. A substantial amount of the sulfur of the coal is captured in the resulting solid effluent.

Abstract: An improved process for reducing the concentration of oxides of nitrogen (NO.sub.x) in a waste stream is provided wherein an effluent stream containing oxides of nitrogen (NO.sub.x) is burned at a temperature greater than about 2000.degree. F. and less than about 3000.degree. F. with an effective amount of an oxygen containing gas and a stoichiometric excess of a hydrocarbon, based on the total amount of available oxygen, to provide a combustion effluent. The combustion effluent is thereafter contacted, at a temperature in the range of from about 1600.degree. F. to about 1800.degree. F., with an effective amount of a gaseous stream containing less than 21 volume percent oxygen to substantially oxidize all combustibles present in the combustion effluent and provide an oxidation effluent substantially free of oxides or nitrogen (NO.sub.x) and combustibles.

Abstract: A combustion process for reducing nitrogen oxides in combustors is proposed wherein combustion takes place successively forming an incomplete combustion zone, a reducing combustion zone, and a complete combustion zone, respectively corresponding to primary burners, secondary burners and air ports or after-burners, successively arranged in the direction of gas stream in a furnace. According to the present invention, it is possible to reduce nitrogen oxides by improving a manner of combustion without providing any denitrating apparatuses for exhaust gas.

Abstract: A method and apparatus for combustion of fuel wherein in two mutually perdicular air swirls are used. In the cylindrical section of the combustor, a horizontal swirl with respect to the combustor is set in motion. The conical section in conjunction with the cylindrical section forms a vertical swirl with respect to the combustor. Notably, the combustor is not dependent upon orientation in a gravity field.

Abstract: A method comprising injecting a primary fuel and air into a furnace to burn the fuel and form a first-stage combustion zone, the fuel being diluted with surrounding combustion gas and the air being supplied at a rate in excess of the stoichiometric rate required for the combustion of the fuel, and injecting a secondary fuel into the furnace around or downstream of the first-stage zone at a range approximately equal to the stoichiometric rate required for the consumption of the excess oxygen resulting from the combustion in the first-stage zone the fuel being diluted with surrounding combustion gas and to form a second-stage combustion zone around or downstream of the first-stage zone.

Abstract: Fuels containing fixed-nitrogen chemical species are combusted in a multi-stage process. The process which converts substantially all of the fixed-nitrogen into molecular nitrogen (and thus avoids the formation of significant amounts of nitrogen oxides from the fixed-nitrogen) comprises six steps: (a) mixing the fuel with at least one first oxidizing agent in amounts such that the equivalence ratio of said fuel to said oxidizing agent is at least about 1.4; (b) partially combusting the mixture resulting from step (a) in at least one first stage at a first temperature of about 1750.degree. to about 2150.degree. K., with a residence time of at least 0.03 second to less than 0.2 second; (c) injecting a free radical agent into the partially combusted mixture of said fuel and said first oxidizing agent; (d) reacting the mixture of said free radical agent and said partially combusted mixture of said fuel and said first oxidizing agent for at least about 0.05 second to about 0.

Abstract: A gas and steam generator having at least two interconnected combustion chambers wherein water in combination with combustible materials is utilized for creating power for a work operation, each combustion chamber being provided with a reduced nozzle-type outlet for creating great pressures and temperatures within the respective chambers, and each combustion chamber being arranged for receiving combustible materials therein for burning thereof. The initial combustion chamber preferably receives a fuel-oxygen mixture at the inlet end thereof for ignition, with the products of the combustion being maintained at a high pressure and temperature by the restrictive nozzle-type outlet of the chamber. Steam and additional combustible materials are introduced at the nozzle outlet of the chamber for ignition and passage into a next stage combustion chamber whereby additional heat and force is produced for ultimate delivery of great power for a work operation.

Abstract: An elongated casing forming a combustion chamber and bearing a venturi type jet nozzle at one end and a fuel and compressed air supply at its opposite end, bears one or more radial passages opening to the venturi to permit a secondary fuel to feed into the flame exiting from the burner for reaction with free oxygen which is unburned from the primary fuel and air mixture entering the combustion chamber at said opposite end of the apparatus. The secondary fuel may be acetylene, methyl-acetylene and its compounds with hydrogen.

Abstract: Fuels containing fixed-nitrogen chemical species are combusted in a multi-stage process. The process which converts substantially all of the fixed-nitrogen into molecular nitrogen (and thus avoids the formation of significant amounts of nitrogen oxides from the fixed-nitrogen) consists of four steps: (a) mixing said fuel with at least one first oxidizing agent in amounts such that the equivalence ratio of said fuel to said oxidizing agent is at least about 1.4; (b) partially combusting the mixture resulting from step (a) in at least one first stage at a first temperature of about 1850.degree. to about 2150.degree. K., with a residence time of at least 0.03 second; (c) mixing the combustion products resulting from step (b) with at least one second oxidizing agent in an amount such that the equivalence ratio of combustion products to the total amount of oxidizing agents in the mixture will be about 1.

Abstract: An elongated casing forming an air cooled combustion chamber includes a venturi type jet nozzle at one end and an ignition system spark plug at its opposite end in axial alignment with the nozzle bore. The spark plug includes a first electrode separated from a second electrode by an annular space. A gas having an oxygen content in excess of that of natural air is introduced to the annular space to improve ignition and internal burner start up. Liquid fuel flow is introduced into the region of extended spark within the combustion chamber and downstream of the ends of the first and second electrodes. Compressed air, after initial cooling of the combustion chamber wall and nozzle, enters the end of the combustion chamber housing the spark plug to create with the fuel a combustible mixture. Some of the compressed air is fed to the annular space between first and second electrodes to maintain the extended spark and improved ignition of the fuel/air mixture.

Abstract: Pellets to be fired are treated with high-temperature gases which, before being supplied to the pellets, are heated by combustion of fuel in a combustion chamber to a temperature above the temperature at which the pellets are to be treated and high enough to ensure that slag formed during combustion can be tapped in liquid form. Cooler gases are then admixed to the high-temperature gases outside the combustion chamber and before they are supplied to the pellets to cool the gases to the temperature desired for the treatment.

Abstract: A method of scrubbing reaction products resulting from flame burning of fuels containing impurities such as sulfur compounds, chlorine compounds, and fluorine compounds. The scrubbing is accomplished by the addition to the fire chamber of additives which bind the impurities. The additives are supplied to the burner flame by way of a gaseous and/or liquid carrier medium flow, accompanied by the formation of a veil surrounding the burner flame.

Abstract: A method of burning fuel with lowered emission of nitrogen oxides comprises feeding pulverized fuel to the main burner in a combustion furnace and additionally feeding pulverized fuel to the region of the furnace where the first fuel is about to conclude its combustion, using inert gas with or without a low oxygen content as a conveying fluid, while supplying oxygen or air to a region downstream of the region for fuel addition.

Abstract: A gas burner capable of automatically shutting off the supply of a gas fuel when the content of the oxygen in the air supplied to the gas burner drops to a predetermined level. It incorporates a Smithell's gas burner as a pilot burner which consists of an inner tube and an outer tube formed with an auxiliary air port. The sizes of these inner and outer tubes as well as the diameter and position of the auxiliary air port are so selected that when the contents of the oxygen in the air supplied to the gas burner drops to a predetermined level, the inner flame cone at the mouth of the inner tube is blown off. A sensor is provided which detects the blown off and generates the output signal in response to which a control means such as a solenoid-operated control valve may close the gas supply pipe. The pilot burner is of the general type in that it can burn gas fuels having different heating values.