A burner sub-system, a furnace comprising the same, a fuel combustion process and steam cracking process carried out in the furnace. The burner sub-system comprises a barrier wall segment between the burner tip and the flue-gas recirculation (FGR) duct, effectively blocking direct gas flow between the burner tip and the FGR duct opening, but without encircling the whole burner tip. The presence of the partial barrier wall has the advantage of preventing the temperature inside the FGR duct from becoming too high, while achieving low NOx emissions from the combustion process without overheating the burner tip because of reduced amount of heat reflection to the burner tip compared to an annular barrier wall. The invention is particularly useful in furnaces where hydrogen-rich fuel gas is combusted.

A fuel-fired burner includes a combustion air inlet for receiving combustion air coupled to a combustion air nozzle at an input to a second chamber within a burner housing spaced apart from a third chamber within the second chamber. The combustion air nozzle directs the combustion air into the third chamber. A fuel inlet coupled to a burner nozzle secured to a burner mounting plate has a recycle port for receiving hot exhaust gas provided to an exhaust gas path. A jet pump located entirely inside the burner housing is configured to receive the hot exhaust gas from the exhaust gas path. The jet pump operates by flowing the combustion air through the combustion air nozzle which suctions in the hot exhaust gas through the recycle port into the exhaust gas path then into a gas mixing zone for mixing the hot exhaust gas and the combustion air.

A burner sub-system, a furnace comprising the same, a fuel combustion process and steam cracking process carried out in the furnace. The burner sub-system comprises a barrier wall segment between the burner tip and the flue-gas recirculation (FGR) duct, effectively blocking direct gas flow between the burner tip and the FGR duct opening, but without encircling the whole burner tip. The presence of the partial barrier wall has the advantage of preventing the temperature inside the FGR duct from becoming too high, while achieving low NOx emissions from the combustion process without overheating the burner tip because of reduced amount of heat reflection to the burner tip compared to an annular barrier wall. The invention is particularly useful in furnaces where hydrogen-rich fuel gas is combusted.

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 refractory apparatus may include a refractory bock comprising a heat shield. The refractory block can include a group of flue gas ports that acts as a gateway for flue gas produced due to combustion downstream of a burner. A suction created in the burner drives the flue gas into the burner through the flue gas ports. A group of staged risers can be housed within the refractory block. The staged risers are protected in staged fuel riser housings in the refractory block. A discharge cone is located in the refractory block for flame stabilization in the burner.

A flame stabilization apparatus with fuel injection upstream of a torpedo, includes a flame stabilization plate that incorporates spokes that stabilize a flame over a range of operations of a burner. The spokes surrounds a fuel plenum with respect to the burner. A first group of fuel ports can be located in a fuel tube upstream of the torpedo and a second group of fuel ports can be located in the flame stabilization plate. A discharge cone includes a discharge zone for the burner, wherein the flame with respect to the flue gas is stabilized at an end of the burner in the discharge zone.

A method and device for reducing emissions of nitrogen oxides and for increasing heat transfer in a fired process heater is disclosed herein. The invention relates generally to the combustion of fuel using some proportion of air as the oxidant which leads to the production of oxides of nitrogen, and more particularly to a method and device that reduces the production of nitrogen oxides from combustion, promotes the appropriate distribution of temperature to reduce fouling of the process tubes in a fired heater, and increases the efficiency of heat transfer to the same process tubes.

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 modular boiler system for implementing fuel combustion is provided. The system includes a first boiler and a second boiler of a plurality of boilers, an oxygen input unit, a fuel input unit, a recycled flue gas input unit, and a flue gas separator. The first boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and recycled flue gas from the recycled flue gas input unit. The first boiler outputs intra-system flue gas. The flue gas separator separates the intra-system flue gas into a first and second flue gas stream, transfers the first flue gas stream to the second boiler, and transfers the second flue gas stream to a gas cleaning system. The second boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and the first flue gas stream from the flue gas separator.

The present invention relates to methods and systems for controlling a combustion reaction and the products thereof. One embodiment includes a combustion control system having an oxygen supply stream and a high concentration carbon dioxide stream, mixing the streams to form an oxygenation stream substantially comprising oxygen and CO2 and having an oxygen to CO2 ratio, then mixing the oxygenation stream with a combustion fuel stream and combusting in a combustor to generate a combustion products stream having a temperature detected by a temperature sensor, the data from which is used to control the flow a carbon dioxide diluent stream to produce a desired temperature of combustion. The system may also include a control system configured to regulate the flow of the oxygen supply stream based on the flow rate and composition of the combustion fuel stream. The system may also include a gas turbine with an expander and having a load and a load controller in a feedback arrangement. Other embodiments include a hydrocarbon analyzer and multiple fuel streams that may be combined to form the combustion fuel stream.