Systems and methods are described for a screen assembly for gas-air mixers in HVAC systems, such as for furnaces. A screen assembly can comprise a mesh screen, a housing, and a pressure tap. The mesh screen can allow for the intake of an air supply while also blocking unwanted foreign matter such as dust or leaves. The housing can receive the air supply and direct it into a gas-air mixer or other component. The pressure tap can be coupled to a gas valve or regulator in order to modulate the flow of gas when air flow is restricted.

The invention is directed to a method for reducing NOx emission from an industrial process furnace comprising a firebox containing a burner and a tube, which method comprises subjecting an oxidant gas and/or a fuel gas (1) to humidification, thereby obtaining a humidified gas; and pre-heating the humidified gas with an external waste heat stream (20) before feeding the gas to the burner.

The invention is directed to a method for reducing NOx emission from an industrial process furnace comprising a firebox containing a burner and a tube, which method comprises subjecting an oxidant gas and/or a fuel gas (1) to humidification, thereby obtaining a humidified gas; and pre-heating the humidified gas with an external waste heat stream (20) before feeding the gas to the burner.

A combustion system includes an ionizer configured to eject charges (or accept charges) for uptake by a combustion reaction to cause a combustion reaction to carry a majority charge or voltage. The ionizer includes an inner electrode, a dielectric body surrounding the inner electrode, and one or more conductive or semi-conductive inner electrodes disposed on the surface of the dielectric body. The inner and outer electrodes are configured to be in a capacitive relationship.

A combustion system includes an ionizer configured to eject charges (or accept charges) for uptake by a combustion reaction to cause a combustion reaction to carry a majority charge or voltage. The ionizer includes an inner electrode, a dielectric body surrounding the inner electrode, and one or more conductive or semi-conductive inner electrodes disposed on the surface of the dielectric body. The inner and outer electrodes are configured to be in a capacitive relationship.

An oxygen-fuel combustor and a method for injecting oxygen and fuel. The oxygen-fuel combustor includes a discharge head unit coupled to a heating furnace and a central supply unit in which, among fuel and primary oxygen, at least the fuel is supplied to the heating furnace. An oxygen supply unit supplies secondary oxygen to the heating furnace. The fuel is injected through a central nozzle unit. Secondary oxygen supplied from the oxygen supply unit is injected through an oxygen nozzle unit. The oxygen nozzle unit includes an accommodation cone part is recessed to decrease in diameter from an entrance. An inclined injection hole part passes through at an incline from the accommodation cone part toward an exit such that the injection direction of the fuel and injection direction of the secondary oxygen cross each other in front of the discharge head unit.

An apparatus for firing and combusting syngas is described. The apparatus comprises a vessel having a first chamber with an inlet for receiving syngas from a gasifier, an ignition chamber provided with an auxiliary burner to ignite the diluted syngas; a combustion chamber provided with an inlet for introducing a combustion agent for combusting the ignited syngas and a retention chamber for retaining the resulting combustion products for a predetermined residence period, the retention chamber being provided with an outlet for withdrawing said combustion products. The first chamber is configured to receive a diluent fluid to dilute the syngas to a predetermined composition below a lower explosive limit (LEL). Preferably the diluent fluid is an oxygen-containing gas.

An apparatus for firing and combusting syngas is described. The apparatus comprises a vessel having a first chamber with an inlet for receiving syngas from a gasifier, an ignition chamber provided with an auxiliary burner to ignite the diluted syngas; a combustion chamber provided with an inlet for introducing a combustion agent for combusting the ignited syngas and a retention chamber for retaining the resulting combustion products for a predetermined residence period, the retention chamber being provided with an outlet for withdrawing said combustion products. The first chamber is configured to receive a diluent fluid to dilute the syngas to a predetermined composition below a lower explosive limit (LEL). Preferably the diluent fluid is an oxygen-containing gas.

A combustion system includes a premix blower system and the premix blower system includes an additional air inlet with an adjustable opening which includes an additional reversibly pluggable air intake. The adjustable opening of the additional air inlet can be opened at higher elevations to compensate for thinner air.

A forced air supply combustion apparatus sucks combustion air from an air supply port. An air filter for collecting foreign matters in the air is mounted on an air-supply-port-formed plate in an insertable and drawable manner. A filter frame is arranged to be brought into close contact with a peripheral part of the air supply port in a state of having mounted the air filter in position. The air-supply-port side edge parts are provided with retaining pieces to clamp a filter side frame part in the Z-axis direction against the side edge parts. A distance in the Z-axis direction between the air-supply-port side edge parts, and the retaining pieces is set larger than a dimension, in the Z-axis direction, of the filter side frame part, and is set smaller than a sum of the dimensions to be obtained by adding to said dimensions the projection height of the projections provided in a projecting manner.