Abstract: A low oxygen vortex burner is provided. With the use of exhaust gas discharged from a combined boiler internal combustion engine as a supply source of air for re-combustion, it is possible to have the exhaust gas discharged in a state of complete combustion and to suppress the pollution of the natural environment due to the exhaust gas.

Abstract: A process for treating an exhaust stream which includes high levels of noxious compounds containing chemically bound nitrogen, to produce an effluent stream that is extremely low in oxides of nitrogen and environmentally safe for discharge into the atmosphere. A source of oxygen and fuel is added to the exhaust stream to create a fuel-rich mixture, the quantity of fuel being sufficient to react with the available oxygen. The fuel-enriched stream is provided to a thermal reactor and reacted to provide a heated oxygen-depleted stream which includes quantities of by-product NO.sub.x, which stream is then cooled to 800.degree. to 1000.degree. F. Conversion oxygen is added to the cooled stream which is then passed over a first catalyst bed under overall reducing conditions, the quantity of conversion oxygen added being in stoichiometric excess of the amount of NO.sub.x in the stream, but less than the amount of combustibles, whereby the NO.sub.x is first oxidized to NO.sub.2, and then the NO.sub.

Abstract: A process and system for low NO.sub.x cogeneration to produce electricity and useful heat. Fuel and oxygen are provided to an internal combustion engine connected to drive an electric generator, to thereby generate electricity. An exhaust stream is recovered from the engine at a temperature of about 500.degree. to 1000.degree. F. which includes from about 6 to 15 percent oxygen. Fuel is added to the exhaust stream to create a fuel-rich mixture, the quantity of fuel being sufficient to react with oxygen and reduce the NO.sub.x in said exhaust stream. The fuel-enriched stream is provided to an afterburner, and the fuel, NO.sub.x and available oxygen are reacted to provide a heated oxygen-depleted stream. The oxygen-depleted stream is cooled in a first heat exchanger. Conversion oxygen is admixed with the cooled stream which is then passed over a catalyst bed under overall reducing conditions. NO is converted to NO.sub.2 at the forward end of the bed, and the NO.sub.

Abstract: A method and corresponding system are provided for reducing quantities of oxides of nitrogen, including N.sub.2 O, that are generated in a coal-fired fluidized bed boiler, the exhaust stream from the fluidized bed boiler being at a temperature of about 600.degree.-650.degree. F. and including from about 3 to 6% oxygen, from about 50 to 500 ppmv of NO.sub.x and from about 50 to 300 ppmv of N.sub.2 O. Pursuant to the invention, the exhaust stream is flowed through a thermal reaction zone at which fuel and air are burned, to provide a modified heated stream which includes small quantities of combustibles and of oxygen. The modified heated stream is passed over a first catalyst bed under overall reducing conditions, the quantity of oxygen in the stream being in stoichiometric excess of the amount of NO.sub.2 O and NO.sub.x, but less than the amount of said combustibles; whereby the N.sub.2 O and NO.sub.x are first oxidized to NO.sub.2, and then the NO.sub.2 is reduced by the excess combustibles.

Abstract: Apparatus for controlled low NO.sub.x combustion. First and second combustion zones are provided, each filled with a porous high temperature resistant matrix, the void spaces of which provide sites at which substantially all of the combustion occurs. The second zone is downstream of the first zone. Means are provided for mixing fuel and a gaseous source of oxygen and providing the resultant combustible mixture to the input end of the first combustion zone to establish fuel-lean conditions therein; and means for feeding the combustion products from the first zone to the second zone and augmenting same with further oxygen and sufficient additional fuel to create fuel-rich burning conditions therein to complete the oxidation of the products from the first zone.

Abstract: Burner apparatus for use in controlled low NO.sub.x combustion. Mixing and flow-directing means receive and mix fuel and air provided thereto and form a flow of the resulting combustible mixture. A combustion zone defined by a porous high temperature-resistant matrix includes an input end for receiving the combustible flow. Cooling means are mounted in proximity to the input end of the combustion zone, for maintaining the temperature of the flowing combustible mixture proximate the input end below ignition temperature, thereby limiting the flame produced by combustion in the porous matrix to the downstream side of the cooling means. The method for controlled low NO.sub.x combustion is also disclosed and claimed.

Abstract: Low NO.sub.x combustion is effected by a method wherein a fuel, e.g., natural gas, and a source of oxygen, e.g., air, are mixed and the mixture is combusted in at least two successive combustion zones filled with a porous matrix, the void spaces of which provide sites at which substantially all of the said combustion occurs; viz. a first zone wherein the mixture is fuel-rich, and a second zone wherein the mixture is fuel-lean. Preferably, the method utilizes an additional combustion zone which precedes or is upstream of the first zone and is filled with a said porous matrix, wherein the mixture is fuel-lean. Apparatus for low NO.sub.

Abstract: A process and system for low NO.sub.x cogeneration to produce electricity and useful heat. Fuel and oxygen are provided to an internal combustion engine connected to drive an electric generator, to thereby generate electricity. An exhaust stream is recovered from the engine at a temperature of about 500.degree. to 1000.degree. F. which includes from about 6 to 15 percent oxygen. Fuel is added to the exhaust stream to create a fuel-rich mixture, the quantity of fuel being sufficient to react with the oxygen and reduce the NO.sub.x in said exhaust stream. The fuel-enriched stream is provided to an afterburner, and the fuel, NO.sub.x and available oxygen are reacted to provide a heated oxygen-depleted stream. The oxygen-depleted stream is cooled in a heat exchanger. Conversion oxygen is admixed with the cooled stream which is then passed over a catalyst bed under overall reducing conditions. NO is converted to NO.sub.2 at the forward end of the bed, and the NO.sub.

Abstract: A process for low NOX incineration which involves incinerating hazardous waste to produce a gaseous stream, adding combustible material to produce a combustible gas stream having combustible material in excess of the oxygen in the combustible gas stream, incinerating the combustible gas stream in a reducing atmosphere to produce a heated oxygen-depleted gaseous stream, converting at least a portion of the heat in the oxygen depleted stream into steam, adding air to the oxygen depleted stream to produce a stoichiometric excess of oxygen in the resultant stream relative to combustible material present in the resultant stream, passing the resultant stream over an oxidizing catalyst to produce an oxidized gaseous stream, removing heat from the oxidized stream, and venting the resultant cooled stream. A system for carrying out the foregoing process is also provided.

Abstract: A process for low NOX combustion which involves combusting an oxygen-containing combustible gas stream having fuel material in excess of the oxygen in the combustible gas stream, whereby the combustible gas stream is combusted in a reducing atmosphere to produce a heated oxygen-depleted gaseous stream, converting at least a portion of the heat in the oxygen-depleted depleted stream into steam, adding air to the oxygen-depleted stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel material present in the resultant stream, passing the resultant stream over the oxidizing catalyst to produce an oxidized gaseous stream, optionally removing heat from the oxidized stream, and venting the resultant cooled stream. A system for carrying out the foregoing process is also provided.

Abstract: A process for low NOX cogeneration to produce electricity and heat which involves combusting fuel to produce a gaseous stream of combustion products, passing the gaseous stream through a turbine to generate electricity, and to produce a gaseous exhaust stream, adding additional fuel to the exhaust stream, to provide a fuel-rich gas stream having fuel in excess of the oxygen in the combustible gas stream, treating the fuel-rich gas stream in a reducing atmosphere to produce a heated oxygen-depleted gaseous stream, converting at least a portion of the heat in the oxygen depleted stream into steam, adding air to the oxygen-depleted stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel present in the resultant stream, passing the resultant stream over an oxidizing catalyst to produce an oxidized gaseous stream, removing heat from the oxidized stream, and venting the resultant cooled stream, the process further providing for cycling to the combusting step at least some of the

Abstract: A process for low NOX cogeneration to produce electricity and heat which involves combusting fuel to produce a gaseous stream of combustion products, passing the gaseous stream through a turbine to generate electricity, and to produce a gaseous exhaust stream, adding additional fuel to the exhaust stream, to provide a gas stream having fuel in excess of the oxygen in the fuel-rich gas stream, catalytically treating the gas stream in a reducing atmosphere to produce a treated gaseous stream, converting at least a portion of the heat in the treated stream into steam, adding air to the treated stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel present in the resultant stream, passing the resultant stream over an oxidizing catalyst to produce an oxidized gaseous stream, removing heat from the oxidized stream, and venting the resultant cooled stream. An apparatus system for carrying out this process is also provided.

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: 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.