Abstract: Fuel such as coal is combusted in a staged combustion device in a method comprising feeding into a first combustion stage of said furnace said fuel and gaseous oxidant containing more than 21 vol. % oxygen, and preferably 21.8 to 29 vol. % oxygen, at a stoichiometric ratio below that which, if the stage were operated with air as the only oxidant, would produce the same amount of NOx, and combusting said fuel with said gaseous oxidant in said combustion stage to produce combustion products and unburned fuel.

Abstract: NOx formation in the combustion of solid hydrocarbonaceous fuel such as coal is reduced by obtaining, from the incoming feed stream of fuel solids and air, a stream having a ratio of fuel solids to air that is higher than that of the feed steam, and injecting the thus obtained stream and a small amount of oxygen to a burner where the fuel solids are combusted.

Abstract: A furnace that combusts fuel, such as coal, of a given minimum energy content to obtain a stated minimum amount of energy per unit of time is enabled to combust fuel having a lower energy content, while still obtaining at least the stated minimum energy generation rate, by replacing a small amount of the combustion air fed to the furnace by oxygen. The replacement of oxygen for combustion air also provides reduction in the generation of NOx.

Abstract: NOx emissions from combustion are reduced, NOx reduction efficiency by SNCR is improved, and other efficiencies are realized, by injecting oxygen into a fuel-rich combustion zone under controlled conditions.

Abstract: A method for atomizing a fluid wherein a gas is heated with the heating facilitating the acceleration of the gas to a high velocity. The accelerated gas contacts the fluid transferring shear, pressure and inertial forces and heat to the fluid effecting efficient atomization of the fluid.

Abstract: Improved operational characteristics such as improved fuel efficiency, reduction of NOx formation, reduction of the amount of unburned carbon in the ash, and lessened tendency to corrosion at the tube wall, in a multi-burner furnace are obtained by reducing the flow rate of combustion air to the burners and selectively individually feeding oxidant to only some of the burners.

Abstract: A method and system is provided for combusting a fuel having application to a heat consuming device such as a boiler or furnace or a reactor. An oxygen-containing stream is introduced into one or more oxygen transport membranes subjected to a reactive purge or a sweep gas. The oxygen transport membrane(s) can advantageously be subjected to a reactive purge or a sweep gas passing in a cross-flow direction with respect to the membranes to facilitate separation of the oxygen. In case of a reactive purge, temperature control of the oxygen transport membrane(s) is effectuated by the use of a suitable heat sink. Further, the oxygen transport membranes can be arranged in a row and be connected in series such that retentate streams of ever lower oxygen concentrations are passed to successive oxygen transport membranes in the row. The fuel or sweep gas can be introduced in a direction counter-current to the bulk flow of the retentate streams.

Abstract: Fuel such as coal is combusted in a staged combustion device in a method comprising feeding into a first combustion stage of said furnace said fuel and gaseous oxidant containing more than 21 vol. % oxygen, and preferably 21.8 to 29 vol. % oxygen, at a stoichiometric ratio below that which, if the stage were operated with air as the only oxidant, would produce the same amount of NOx, and combusting said fuel with said gaseous oxidant in said combustion stage to produce combustion products and unburned fuel.

Abstract: A system for combusting difficult to combust fluid such as waste fluid wherein fuel and gaseous oxidant combust in a hot combustion gas chamber to form a hot combustion gas mixture which is accelerated to a high speed and at a steady, i.e. non-pulsing, flow is then used to atomize and then combust the fluid.

Abstract: Fuel such as coal is combusted in a staged combustion device in a method comprising feeding into a first combustion stage of said furnace said fuel and gaseous oxidant containing more than 21 vol. % oxygen, and preferably 21.8 to 29 vol. % oxygen, at a stoichiometric ratio below that which, if the stage were operated with air as the only oxidant, would produce the same amount of NOx, and combusting said fuel with said gaseous oxidant in said combustion stage to produce combustion products and unburned fuel.

Abstract: A method for atomizing a fluid wherein a gas is heated with the heating facilitating the acceleration of the gas to a high velocity. The accelerated gas contacts the fluid transferring shear, pressure and inertial forces and heat to the fluid effecting efficient atomization of the fluid.

Abstract: An oxygen separation and combustion apparatus such as a boiler or a nitrogen generator in which a plurality of fluid passages and oxygen transport membranes are located within a combustion chamber. The oxygen transport membranes separate oxygen from an oxygen containing gas, thereby to provide the oxygen within the combustion chamber to support combustion of a fuel and thereby to generate heat. The fluid passages are positioned to allow a portion of the heat to be transferred from the combustion to the oxygen transport membranes to heat said oxygen transport membranes to an operational temperature and a further portion of the heat to be transferred from the combustion to the fluid, thereby to heat the fluid and also, to help stabilize the operational temperature of said oxygen transport membranes. Fuel is introduced into the combustion chamber by injection or as a mixture with circulated flue gas.

Abstract: A method and system is provided for combusting a fuel having application to a heat consuming device such as a boiler or furnace or a reactor. An oxygen-containing stream is introduced into one or more oxygen transport membranes subjected to a reactive purge or a sweep gas. The oxygen transport membrane(s) can advantageously be subjected to a reactive purge or a sweep gas passing in a cross-flow direction with respect to the membranes to facilitate separation of the oxygen. In case of a reactive purge, temperature control of the oxygen transport membrane(s) is effectuated by the use of a suitable heat sink. Further, the oxygen transport membranes can be arranged in a row and be connected in series such that retentate streams of ever lower oxygen concentrations are passed to successive oxygen transport membranes in the row. The fuel or sweep gas can be introduced in a direction counter-current to the bulk flow of the retentate streams.

Abstract: An oxygen separation and combustion apparatus such as a boiler or a nitrogen generator in which a plurality of fluid passages and oxygen transport membranes are located within a combustion chamber. The oxygen transport membranes separate oxygen from an oxygen containing gas, thereby to provide the oxygen within the combustion chamber to support combustion of a fuel and thereby to generate heat. The fluid passages are positioned to allow a portion of the heat to be transferred from the combustion to the oxygen transport membranes to heat said oxygen transport membranes to an operational temperature and a further portion of the heat to be transferred from the combustion to the fluid, thereby to heat the fluid and also, to help stabilize the operational temperature of said oxygen transport membranes. Fuel is introduced into the combustion chamber by injection or as a mixture with circulated flue gas.

Abstract: A method and system to separate oxygen from air for producing oxygen to support combustion of a fuel, thereby to produce heat in a heat consuming device. In accordance with the method and system a heated and compressed air stream is introduced into a ceramic membrane system having one or more oxygen-selective, ion conducting membranes to produce an oxygen permeate stream which is used to support combustion of the fuel. The compressed air stream is heated within the heat consuming device itself which can be, for instance, a furnace or a boiler, through indirect heat exchange with flue gases or by radiant heat within a radiant heat exchange zone thereof. An oxygen lean retentate stream, produced through separation of oxygen from the compressed and heated air stream, can be expanded with the performance of work to produce an expanded air stream. The work of expansion can be applied to the compression of the incoming air stream. The expanded air stream can be used to preheat the compressed and heated air stream.

Abstract: A system for combusting difficult to combust fluid such as waste fluid wherein fuel and gaseous oxidant combust in a hot combustion gas chamber to form a hot combustion gas mixture which is accelerated to a high speed and at a steady, i.e. non-pulsing, flow is then used to atomize and then combust the fluid.

Abstract: A method for providing reagent to a remote reaction zone wherein reagent preferably is mixed with carrier gas and maintained within the carrier gas as it is passed as a coherent jet through a distance to the reaction zone. The jet passes the leading edge of a confining flame envelope, loses its coherency and delivers the reagent to the reaction zone for reaction therein.

Abstract: A method for reducing the NOx content of combustion gases from combustion in a commercial furnace wherein hot oxygen and carbonaceous fuel such as pulverized coal react to form a fuel-rich gas phase mixture which is then used to reduce NOx to nitrogen gas.