Abstract:
The invention relates to a boiler or furnace (10) for combustion of fuel in an air staged combustion mode, comprising an enclosure (12) having walls (16) defining a combustion chamber (14), of which walls (16) at least a part is provided with heat exchanging tubes (18) for generating a heated fluid, at least one burner (22) for combustion of fuel positioned in one (20) of the walls (16) and provided with a fuel supply (26) and a primary air supply (24), and a secondary air supply (32), and an outlet (28) for discharge of flue gas, wherein the secondary air supply (32) is a manifold system comprising an inlet (38; 54) through the wall (20), in fluid communication with a distribution channels (46) positioned internally of the enclosure (12) and the heat exchanging tubes (18) downstream of the at least one burner (22) in a secondary combustion zone.
Abstract:
A method for staged combustion in a combustor assembly includes introducing an oxidant stream and a fuel stream at a first location into a combustion chamber to produce a heated stream. A Liquid water stream and an additional oxidant stream, fuel stream or both are then introduced into the heated stream in at least one location along the heated stream downstream from the first location. The additional oxidant stream, fuel stream or both react in the heated stream to generate additional heat that vaporizes liquid water from the liquid water stream to water vapor.
Abstract:
The present invention relates to a method and furnace for generating straightened flames in a steam methane reformer or ethylene cracking furnace where fuel-staged burners are used. Fuel staging may be used for reducing NOx emissions. Criteria for generating straightened flames are provided. These criteria relate to oxidant conduit geometry and furnace geometry. Techniques for modifying the furnace and/or burners to achieve these criteria are also provided.
Abstract:
A combustor for a gas turbine engine includes outer and inner liners defining a combustion chamber and an igniter mounted to the outer liner. A dome plate is disposed between the outer and inner liners and has a plurality of circumferentially spaced openings formed therein. A fuel-air mixer is disposed in each one of the openings; each fuel-air mixer includes a swirler mounted in the corresponding opening and a fuel nozzle received in the corresponding swirler. Two adjacent ones of the swirlers are low air flow swirlers in general circumferential alignment with the igniter and the rest of the swirlers are higher air flow swirlers. Each one of the fuel nozzles provides a similar amount of fuel so that the two fuel-air mixers having low air flow swirlers produce a local region of increased fuel-to-air ratio in the vicinity of the igniter.
Abstract:
A process and apparatus for cyclonic combustion with ultra-low pollutant emissions and high efficiency wherein a fuel and primary combustion air mixture is tangentially injected into a reducing primary combustion zone of a cyclonic combustor. The primary combustion air is injected into the reducing primary combustion zone in an amount equal to between about 30% and about 90% of a stoichiometric requirement for complete combustion of the fuel. Secondary combustion air is tangentially injected into an oxidizing secondary combustion zone of the cyclonic combustor, in an amount equal to between about 10% and about 90% of the stoichiometric requirement for complete combustion of the fuel. Primary combustion products from the reducing primary combustion zone are mixed with the tangentially injected secondary air for completing combustion within the oxidizing secondary combustion zone. Combustion chamber walls which define the reducing primary combustion zone and the oxidizing secondary combustion zone are water-cooled.
Abstract:
A method comprises providing a combustion apparatus having an outer vessel and an inner conduit. The outer vessel has a first wall that defines an internal volume. The inner conduit is at least partially positioned within the internal volume and provides a fluid passageway that is in communication therewith. The method further comprises introducing oxygen into the internal volume in a manner such that the oxygen swirls within the internal volume and around the inner conduit. Furthermore, the method comprises introducing fuel into the internal volume, and combusting the fuel and oxygen at least partially therewithin. The combustion of the fuel and oxygen produces reaction products and the method further comprises discharging at least some of the reaction products from the internal volume via the fluid passageway of the inner conduit.
Abstract:
Combustion method and apparatus for NOx reduction which are capable of achieving NOx reduction with the value of exhaust NOx under 10 ppm, as well as CO reduction at the same time. The combustion method for fulfilling NOx reduction and CO reduction by suppressing temperature of combustion gas derived from a burner comprises a NOx reduction step for suppressing combustion gas temperature in such a manner that suppression of NOx generation is preferred to reduction of exhaust CO value, thereby keeping NOx value not more than a specified value, and a CO reduction step for thereafter reducing exhaust CO value resulting from the NOx reduction step to not more than a specified value.
Abstract:
A combustor for a gas turbine engine includes outer and inner liners defining a combustion chamber and an igniter mounted to the outer liner. A dome plate is disposed between the outer and inner liners and has a plurality of circumferentially spaced openings formed therein. A fuel-air mixer is disposed in each one of the openings; each fuel-air mixer includes a swirler mounted in the corresponding opening and a fuel nozzle received in the corresponding swirler. Two adjacent ones of the swirlers are low air flow swirlers in general circumferential alignment with the igniter and the rest of the swirlers are higher air flow swirlers. Each one of the fuel nozzles provides a similar amount of fuel so that the two fuel-air mixers having low air flow swirlers produce a local region of increased fuel-to-air ratio in the vicinity of the igniter.
Abstract:
An apparatus is disclosed for reducing the production of NOx in an engine. One embodiment of the apparatus comprises a plurality of mixing cans in which air is drawn into the flow of gaseous fuel therethrough. The gaseous mixture formed by one of the mixing cans is transmitted to the engine at a rate which increases with the load on the engine, and the other mixing cans are serially brought on line after the preceeding mixing cans reach their predetermined rate.
Abstract:
A combustion method which employs highly fuel-rich combustion and highly fuel-lean combustion separately and simultaneously within a combustion zone followed by intermixture of their resulting gases within the combustion zone for further combustion.