A method for burning primary fuel (F1), wherein the primary fuel (F1) comprises at least a first compound containing nitrogen and a second compound comprising sulfur. The method comprises producing primary combustion gas (G1) having a temperature of at least 450° C. and comprising oxygen; feeding the primary fuel (F1) and the primary combustion gas (G1) to a primary process zone (Z1) of a furnace (200); feeding tertiary combustion gas (G3) to a secondary process zone (Z2) of the furnace (200); letting the primary fuel (F1), the primary combustion gas (G1), and/or their reaction products to move from the primary process zone (Z1) via the secondary process zone (Z2) to a tertiary process zone (Z3) of the furnace (200); and feeding quaternary combustion gas (G4) comprising oxygen to the tertiary process zone (Z3) of the furnace (200). An embodiment comprises collecting the primary fuel (F1) from a pulp process. A corresponding system.

A method of melting a charge in a double-pass tilt rotary furnace having a door, including operating a first burner at a first firing rate, the first burner being mounted in a lower portion of the door and producing a first flame having a length; operating a second burner at a second firing rate, the second burner being mounted in an upper portion of the door and producing a second flame having a length, the second flame being distal from the charge relative to the first flame; in an initial phase when the solids in the charge impede the first flame, controlling the second firing rate to be greater than the first firing rate; and in an later phase after melting of the solids in the charge sufficiently that the first flame is not impeded, controlling the first firing rate to be greater than the second firing rate.

A thermophotovoltaic generator incorporating a two-stage combustor for providing heat to a thermophotovoltaic cell. Combustor parts include a partial oxidation reactor, which functions catalytically to convert a hydrocarbon fuel and a first supply of an oxidant into a gaseous partial oxidation product; and further include downstream thereof, a deep oxidation reactor including a premixer plenum fluidly connected to a heat spreader comprising a porous matrix, such as a ceramic foam. Functionally, the deep oxidation reactor converts the gaseous partial oxidation product and a second supply of oxidant into complete combustion products. Heat produced by the two-stage combustor generates radiative energy from a photon emitter, which is directly converted to electricity in a photovoltaic diode cell.

The present invention relates to a combustion heater (100) for providing controlled heat (H) to an endothermic reaction process. The combustion heater comprises an integrated burner (20) to yield a hot burner exhaust gas (35) flow from burning a first fuel. The burner exhaust gas mixed with oxidant flows to a flue gas outlet along a flue gas flow path (FGP). Provided to the combustion chamber at a position outside a direct reach of flames from the burner is a secondary fuel conduit (30) with a plurality of nozzles (31) from which a second fuel (32) is transferred into a flow along the said flue gas flow path (FGP). The resulting combustion of the second fuel can be used to provide controlled heat to the to endothermic reaction operated in a reaction conduit (40) that is in thermal heat exchange with the combustion chamber.

A method for operating a combustion chamber is provided. The method includes introducing a fuel into the combustion chamber via a plurality of nozzles, each nozzle having an associated stoichiometry for an output end of the nozzle. The method further includes measuring the stoichiometry of each nozzle via one or more sensors to obtain stoichiometric data, and determining that at least one of a frequency and an amplitude of spectral line fluctuations derived from the stoichiometric data has exceeded a threshold. The method further includes adjusting the stoichiometry of at least one of the nozzles based at least in part on the stoichiometric data so as to maintain a flame stability of the combustion chamber.

A burner and methods of using the burner. The burner utilizes bypass conduits to separate the combustion air that is passed to the primary combustion zone into two or more portions. The two portions are injected into the primary combustion zone at different points so as to reduce the flame temperature. A NOx reducing medium may be mixed with the combustion air in the bypass conduit. The NOx reducing medium may be flue gases from a combustion chamber having the primary combustion zone.

The present invention relates to the supplying power to burners for oxy-fuel combustion glass melting furnaces, including a fuel injecting means and a hot oxygen power supplying means, the dispensing of oxygen being carried out so as to develop a staged combustion, a fraction of the oxygen being concurrently injected into the fuel, said oxygen being supplied essentially without heating prior to the supplying thereof into the fuel injecting means.

A burner assembly for and method of producing ethylene having a mechanism to inject either primary fuel, staged fuel, or both by premix methods before combustion in a furnace. The burner assembly has at least one premix injection assembly for either exclusively primary fuel or exclusively staged fuel injection paired with a nozzle mix injection or injection means for primary and staged fuel both by premix methods. The primary fuel premix assembly associates with a burner tile that consists of multiple inlets and outlets connected by venturi channels to direct and combine combustion air and staged fuel coming from staged fuel orifice spuds. Primary fuel and combustion air are mixed in a premix assembly and directed inside the furnace, and above the burner tile to complete the reaction with the staged fuel and combustion air mixture in a combustion zone inside of the furnace.

A system and method for synchronized oxy-fuel boosting of a regenerative glass melting furnace including first and second sets of regenerative air-fuel burners, a first double-staged oxy-fuel burner mounted in a first wall, and a second double-staged oxy-fuel burner mounted in a second wall, each oxy-fuel burner having a primary oxygen valve to apportion a flow of oxygen between primary oxygen and staged oxygen and a staging mode valve to apportion the flow of staged oxygen between an upper staging port and a lower staging port in the respective burner, and a controller programmed to control the primary oxygen valve and the staging mode valve of each of the first and second oxy-fuel burners to adjust flame characteristics of the first and second oxy-fuel burners depending on the state of operation of the furnace.

A device heating a fluid and usable in a rocket launcher to pressurize a liquefied propellant. The device includes a first burner performing first combustion between a limiting propellant and an excess propellant; a first heat exchanger in which first burnt gas from the first combustion transfers heat to the fluid; at least one second burner into which both the first burnt gas and some limiting propellant are injected to perform second combustion between the limiting propellant and at least a portion of unburnt excess propellant present in the first burnt gas. The second burnt gas from the second combustion flows through a second heat exchanger to transfer heat to the fluid. Burnt gas from each combustion flows in respective burnt gas tubes within a common overall heat exchanger including the heat exchange units, the gas transferring heat to the fluid, the fluid flowing between the burnt gas tubes.