A system for providing combustion air and fuel gas to a premix burner includes a premix engine, a premix burner in fluid communication with an outlet of the premix engine, an exhaust flue, a flue gas recirculation line in fluid communication with the flue and an inlet of the premix engine, and a fresh air line in fluid communication with a source of fresh air and the inlet of the premix engine. A flue gas flow restrictor is installed in the flue gas recirculation line, and a fresh air flow restrictor is installed in the fresh air line. The flow restrictors are sized so that the premix engine, in operation, draws recycled flue gas and fresh air from the recycled flue gas line and fresh air line, respectively, in a predetermined proportion.

A low NOx combustion method includes steps of injecting reactants into a combustion chamber. A primary reactant stream, including fuel and combustion air premix, is injected from a premix burner port into the combustion chamber. A staged fuel stream is injected into the combustion chamber from a staged fuel injector port adjacent to the premix burner port. A stream of recirculated flue gas is injected into the combustion chamber from a flue gas injector port that is adjacent to the premix burner port and adjacent to the staged fuel injector port. In this manner, the stream of recirculated flue gas is injected into the combustion chamber unmixed with the primary reactant stream and unmixed with the staged fuel stream.

A gaseous fuel-air-flue gas burner is described herein. One device includes a housing having a combustion chamber containing a combustion area in which a combination of fuel, air, and flue gas mix to form a flame, a flame arrester having an outer surface for the flame to form, a supply chamber configured to receive the fuel, air, and flue gas mixture at an inlet and provide the combustion area with the fuel, air, and flue gas mixture at an outlet to produce a flame and a quantity of return flue gas, and a return cavity configured to move return flue gas away from the combustion area and into the inlet of the supply chamber.

A combustion system including a bypass which opens to the open air during two different operating modes (conventional combustion; oxy-combustion), and which has the function, on the one hand, in the two operating modes, when the discharge valve is at least partially open and the recycling valve is closed or open, of allowing air to enter the recycling loop, and which has the function, on the other hand, in the second operating mode, when the discharge valve is closed and the recycling valve is open, of allowing a surplus of the combustion gas produced by the combustion device to be discharged from the recycling loop, the other fraction of the combustion gas produced by the combustion device supplying the mixer.

The invention relates to a device (2) and a method for supplying combustion air and for recirculating exhaust gas for a burner (1) comprising a combustion chamber (10) and to a burner (1) comprising a device (2) for supplying combustion air and for recirculating exhaust gas. Multiple drive nozzles (21) distributed about a central axis (A) are used to supply combustion air to a mixing chamber (22) arranged downstream of the drive nozzles (21) by suctioning exhaust gases out of the combustion chamber (10); the combustion air exiting the drive nozzles (21) is mixed with exhaust gases in the mixing chamber (22) in order to form a combustion air/exhaust gas mixture, said exhaust gases flowing out of the combustion chamber (10) and being backflushed by means of the drive nozzles (21); and the combustion air/exhaust gas mixture is supplied to a reaction zone downstream of the mixing chamber (22).

A burner and methods of using the burner. The burner produces a flame from combustion air and fuel gas. Flue gas, also produced, can be withdrawn and recycled to the burner. A cooling or condition gas, such as ambient air, may be mixed with the flue gas to reduce its temperature. The burner may also utilize a stage injection so that a portion of the produced flue gas is recycled internally.

A recuperative burner having a burner base and a combustion chamber tube in which at least one burner nozzle is positioned. An exhaust gas recirculation device has a jet pump operated by combustion air and comprises a jet nozzle. A jet pump annular gap is provided for the intake of exhaust gases from outside the combustion chamber tube via an annular driving jet. The exhaust gas recirculation device being configured upstream of the mixing plane of the fuel gases flowing into the combustion chamber tube, between the burner base and the combustion chamber tube and comprises at least one endless exhaust gas intake opening and/or a peripheral, self-contained arrangement of a plurality of exhaust gas intake openings, from which at least one flow path leads into the interior of the combustion chamber tube. A recuperator is arranged upstream of the combustion chamber tube and has a heat transfer body.