Abstract: Methods and apparatus for combustion of a hydrocarbon fuel in a combustion chamber of a furnace or boiler are presented, the combustion normally using only air as an oxidant, part of the air entering the combustion chamber through one or more burners, and a remaining portion of air entering the combustion chamber at a plurality of locations downstream of the burners. The methods comprise injecting oxygen-enriched gas through a plurality of lances into the combustion chamber at a plurality of downstream locations, the oxygen-enriched gas injected at a velocity ranging from subsonic to supersonic, and the oxygen-enriched gas being present in an amount sufficient to provide an oxygen concentration of no more than 2% on a volume basis greater than when air is used alone as oxidant.

Abstract: A retrofit technology for air-fuel fired, vertical glass furnace for oxygen firing or boosting to provide additional heat to the process to increase furnace production capacity. The additional firing using oxygen is strategically controlled to enable enhanced radiation from oxygen flame for the spheroidizing process without negative effects on the overall process. With proper implementation, an increased production from 50% to 200%, depending on the size of the spheres, can be achieved while maintaining acceptable product quality. Processes in accordance with the present invention can be performed using one of a number of methods of oxygen boosting.

Abstract: Methods and apparatus for combustion of a hydrocarbon fuel in a combustion chamber of a furnace or boiler are presented, the combustion normally using only air as an oxidant, part of the air entering the combustion chamber through one or more burners, and a remaining portion of air entering the combustion chamber at a plurality of locations downstream of the burners. The methods comprise injecting oxygen-enriched gas through a plurality of lances into the combustion chamber at a plurality of downstream locations, the oxygen-enriched gas injected at a velocity ranging from subsonic to supersonic, and the oxygen-enriched gas being present in an amount sufficient to provide an oxygen concentration of no more than 2% on a volume basis greater than when air is used alone as oxidant.

Abstract: Methods and apparatus for combustion of a hydrocarbon fuel in a combustion chamber of a furnace or boiler are presented, the combustion normally using only air as an oxidant, part of the air entering the combustion chamber through one or more burners, and a remaining portion of air entering the combustion chamber at a plurality of locations downstream of the burners. The methods comprise injecting oxygen-enriched gas through a plurality of lances into the combustion chamber at a plurality of downstream locations, the oxygen-enriched gas injected at a velocity ranging from subsonic to supersonic, and the oxygen-enriched gas being present in an amount sufficient to provide an oxygen concentration of no more than 2% on a volume basis greater than when air is used alone as oxidant.

Abstract: An oxy-fuel burner generates a long, luminous, stable and adjustable flame temperature profile flame by incorporating separate, fuel and oxygen jets oriented in a unique geometry. In one preferred embodiment, the fuel is injected horizontally at medium injection velocity (50-200 m/s) while primary oxygen is injected underneath the fuel jet at supersonic velocity (300-500 m/s). The supersonic velocity oxygen jet (20 to 50% required for stoichiometric combustion) entrains fuel and furnaces gases in it's core for the primary flame development over the furnace load. The subsequent mixing of the fuel, primary oxygen and entrained furnace gases establish a low NOx, stable, long and luminous primary flame. The secondary oxidant, preferably air or low purity oxygen (50 to 80% of stoichiometric needs), is injected above the flame using one or more oxygen jets to create an oxy-fuel flame with adjustable flame characteristics.

Abstract: Methods and apparatus for combusting a fuel with an oxidant are described, the apparatus comprising a ceramic burner block, the burner block having a back face and a front face. The burner block has at least one oxidant cavity in an upper portion of the burner block, and at least one fuel cavity in a lower portion of the burner block, each cavity extending from the back face to the front face. The at least one oxidant cavity has positioned therein a fuel supply conduit, the fuel supply conduit having a fuel supply conduit exit positioned a sufficient distance from the front face to allow combustion of at least a portion of fuel exiting the fuel supply conduit exit with at least some of the oxidant traversing the oxidant cavity, and the least one fuel cavity having connected thereto, near the back face, an oxidant conduit, thereby allowing mixing of a minor portion of the oxidant with the fuel.

Abstract: An oxy-fuel burner generates a long, luminous, stable and adjustable flame temperature profile flame by incorporating separate, fuel and oxygen jets oriented in a unique geometry. In one preferred embodiment, the fuel is injected horizontally at medium injection velocity (50-200 m/s) while primary oxygen is injected underneath the fuel jet at supersonic velocity (300-500 m/s). The supersonic velocity oxygen jet (20 to 50% required for stoichiometric combustion) entrains fuel and furnaces gases in it's core for the primary flame development over the furnace load. The subsequent mixing of the fuel, primary oxygen and entrained furnace gases establish a low NOx, stable, long and luminous primary flame. The secondary oxidant, preferably air or low purity oxygen (50 to 80% of stoichiometric needs), is injected above the flame using one or more oxygen jets to create an oxy-fuel flame with adjustable flame characteristics.

Abstract: Methods and apparatus for combustion of a hydrocarbon fuel in a combustion chamber of a furnace or boiler are presented, the combustion normally using only air as an oxidant, part of the air entering the combustion chamber through one or more burners, and a remaining portion of air entering the combustion chamber at a plurality of locations downstream of the burners. The methods comprise injecting oxygen-enriched gas through a plurality of lances into the combustion chamber at a plurality of downstream locations, the oxygen-enriched gas injected at a velocity ranging from subsonic to supersonic, and the oxygen-enriched gas being present in an amount sufficient to provide an oxygen concentration of no more than 2% on a volume basis greater than when air is used alone as oxidant.

Abstract: A retrofit technology for air-fuel fired, vertical glass furnace for oxygen firing or boosting to provide additional heat to the process to increase furnace production capacity. The additional firing using oxygen is strategically controlled to enable enhanced radiation from oxygen flame for the spheroidizing process without negative effects on the overall process. With proper implementation, an increased production from 50% to 200%, depending on the size of the spheres, can be achieved while maintaining acceptable product quality. Processes in accordance with the present invention can be performed using one of a number of methods of oxygen boosting.

Abstract: Methods and apparatus for combusting a fuel with an oxidant are described, the apparatus comprising a ceramic burner block, the burner block having a back face and a front face. The burner block has at least one oxidant cavity in an upper portion of the burner block, and at least one fuel cavity in a lower portion of the burner block, each cavity extending from the back face to the front face. The at least one oxidant cavity has positioned therein a fuel supply conduit, the fuel supply conduit having a fuel supply conduit exit positioned a sufficient distance from the front face to allow combustion of at least a portion of fuel exiting the fuel supply conduit exit with at least some of the oxidant traversing the oxidant cavity, and the least one fuel cavity having connected thereto, near the back face, an oxidant conduit, thereby allowing mixing of a minor portion of the oxidant with the fuel.

Abstract: A high-speed jet of liquid oxygen (21) with a speed higher than 100 meters per second is delivered into the tuyeres of a blast furnace of cupola furnace together with pulverised carbon. The jet reaches the opposite wall of the cavity (9) formed at the outlet of the tuyere (6) in the mass of material contained in the shaft. Supplying oxygen to the bottom of the cavity improves the burning of the remaining coal, whereby higher injection levels may be achieved. The shape of the cavity may also be altered, and, in particular, faster reactions may be achieved in the axial region of the shaft.

Abstract: A process for thermal debinding and sintering of a workpiece made by molding a mixture of a binder and a powder, the process entailing the steps of injection molding a workpiece entailing at least 30% vol. of binder, the binder containing from about 70% to about 90% wt. of at least one wax and from about 10% to 30% wt. of high molecular weight polymer, introducing the molded workpiece in an enclosure at ambient temperature, injecting an atmosphere of at least 95% vol. hydrogen and less than 5% vol. water vapor, heating the enclosure and/or the workpiece until reaching a temperature between about 150.degree. C. to about 200.degree. C., maintaining the temperature during a period of time sufficient to substantially decompose all the waxes in the binder, then heating again the enclosure and/or the workpiece to reach a temperature of about 700.degree. C.

Abstract: A process for controlling the carbon content in a metallic piece molded by injection or other process comprising,a) heating the shaped piece under a 100% hydrogen atmosphere up to about 200.degree. C.,b) replacing the 100% H.sub.2 atmosphere by a substantially 100% nitrogen atmosphere and heating the pieces from 200.degree. C. to 450.degree. C.,c) maintaining the temperature in the enclosure at substantially 450.degree. C. while subjecting the pieces to an atmosphere comprising from 15% to 100% vol. hydrogen, the complement being nitrogen, thend) replacing the atmosphere by a substantially 100% nitrogen ande) heating the pieces from 450.degree. C. to substantially 700.degree. C. in order to further eliminate the remaining binder.

Abstract: A process is provided for preparing carbon-containing substantially oxide-free iron powders or iron-based powders or both wherein oxygen impurities from an iron powder are removed without substantial decarburization, by heating the iron powder or iron-based powders or both under a substantially pure hydrogen atmosphere from ambient temperatures to a first intermediate temperature in an enclosure, then replacing the substantially pure hydrogen atmosphere by a substantially pure nitrogen atmosphere in the enclosure and then heating the powder to a second temperature which is higher that the first intermediate temperature, then cooling down the powder under an inert atmosphere to at least a temperature where substantially no more oxidation of the powder occurs, then removing the powder from the enclosure, the first and second temperatures being sufficient to reduce substantially all oxide impurities in the powder without substantial decarburization.