A combustion system such as a furnace or boiler includes a perforated reaction holder configured to hold a combustion reaction that produces very low oxides of nitrogen (NOx).

Premixing fuel and oxidizer in a burner to form a flammable mixture is described. The burner is configured to reduce formation of a pollutant when the fuel and the oxidizer are combusted while deterring upstream propagation of the combustion reaction. The burner includes a mixer for premixing fuel and oxidizer to form a flammable mixture to be supplied to a reaction zone for a combustion reaction and a flame arrestor for deterring upstream propagation of the combustion reaction. In some embodiments, the mixer and the flame arrestor include a packing volume. In some embodiments, the mixer and the flame arrestor include at least a first packing volume for containing first packing, a second packing volume for containing second packing, and a packing gap in fluid communication between the first packing volume and the second packing volume.

A combustion system such as a furnace or boiler includes a perforated reaction holder configured to hold a combustion reaction that produces very low oxides of nitrogen (NOx).

The pre-mix burner assembly includes a jet pump comprising a suction chamber, a flue gas inlet, and a combustion air tube with a combustion air nozzle. The combustion air inlet includes a combustion air tube with a tapered nozzle, and it is connected to a combustion air fan. The flue gas inlet is connected to the suction chamber and the combustion air fan. The suction chamber surrounds the combustion air tube, and it has a jet pump nozzle with a discharge. The assembly includes a fuel gas inlet connected to the combustion air tube. The combustion air and fuel gas mixture exits the combustion air nozzle creating a negative pressure in the suction chamber and drawing flue gas into the suction chamber. The assembly includes a mixing tube positioned downstream of the jet pump discharge, and a burner block connected to an outlet of the mixing tube.

A method is disclosed for controlling fuel injection in a reheat combustor of a gas turbine combustor assembly including a combustor casing defining a gas flow channel and a plurality of injection nozzles distributed in or around the gas flow channel; the method includes the step of distributing fuel among the injection nozzles according to a non-uniform distribution pattern.

In a fuel and oxidant combustion system, a flame holder support structure includes a heating element that receives electrical energy from an electrical power source. The heating element is raised to an auto-ignition temperature of a fuel and oxidant mixture directed, along an axis proximate the flame holder support structure, to a flame holder for combustion thereof.

A combustor arrangement for a gas turbine includes a first burner, a first combustion chamber, a mixer for admixing a dilution gas to the gases leaving the first combustion chamber during operation, a second burner, and a second combustion chamber arranged sequentially in a fluid flow connection. These elements of the combustor arrangement are arranged in a row to form a flow path extending between the first combustion chamber and the second burner. The combustor arrangement includes acentral lance body arranged inside the flow path and extending from the first burner through the first combustion chamber into the mixer and into the second burner, wherein the lance body includes a fuel duct for providing fuel for the first burner and/or for the second burner.

A method is disclosed for operating an axially staged mixer arrangement with dilution air or dilution gas injection in connection with a combustion arrangement of a gas turbine engine or turbo machinery, having at least one combustion chamber, at least one mixer arrangement for admixing air or gas portions to the hot gas flow leaving the combustion chamber. The mixer arrangement includes a plurality of injectors for admixing air portions to cool at least the hot gas flow leaving combustion chamber. The spacing between the last injection location of acting injectors and at least one subsequently arranged dilution air injection, inside of the mixer arrangement in the hot gas flow, where there is no node between the injection locations, corresponds to a distance equal or approximating to half of convective wave length.

A method for converting a gas boiler into a liquid-fuel boiler. The gas boiler comprises an enclosure which accommodates a firebox, which forms a combustion chamber and is provided with a supporting wall which supports a burner provided with a combustion head, which protrudes from the supporting wall and has a substantially cylindrical shape with an internal cavity formed axially; the enclosure is provided with a passage in which an atomizing nozzle, connected to a liquid fuel supply duct, and at least one ignition electrode are inserted from the outside; a snorkel-shaped body is also applied to the end of the combustion head that is opposite with respect to the supporting wall and the supply duct is connected supply duct is connected to a pressurized source of liquid fuel.

According to an embodiment, a combustion system is provided, which includes a nozzle configured to emit a diverging fuel flow, a flame holder positioned in the path of the fuel flow and that includes a plurality of apertures extending therethrough, and a preheat mechanism configured to heat the flame to a temperature exceeding a startup temperature threshold.