Abstract:
PROBLEM TO BE SOLVED: To provide a method and a device for generating straightened flames in a steam methane reformer or ethylene cracking furnace. SOLUTION: Fuel staging may be used for reducing NOx emissions. Criteria for generating straightened flames are provided. These criteria relate to oxidant pipe geometry and furnace geometry. Techniques for modifying the furnace and/or burners to achieve these criteria are also provided. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a method and a device for low NOx combustion capable of simultaneously realizing a reduction in NOx and and a reduction in CO to lower discharged NOx value to 10 ppm or below. SOLUTION: This low NOx and low CO combustion method capable of realizing a reduction in NOx and a reduction in CO by controlling the temperature of combustion gas from a burner comprises a low NOx step for lowering NOx value to a specified value or below by suppressing the temperature of the combustion gas while preferring the suppression of generation of NOx over a reduction in exhausted CO value and a low CO step for lowering the exhausted CO value in the low NOx step to a specified value or below. COPYRIGHT: (C)2004,JPO
Abstract:
High efficiency processes for producing olefins, alkynes, and hydrogen co-production from light hydrocarbons are disclosed. In one version, the method includes the steps of combusting hydrogen and oxygen in a combustion zone of a pyrolytic reactor to create a combustion gas stream, transitioning a velocity of the combustion gas stream from subsonic to supersonic in an expansion zone of the pyrolytic reactor, injecting a light hydrocarbon into the supersonic combustion gas stream to create a mixed stream including the light hydrocarbon, transitioning the velocity of the mixed stream from supersonic to subsonic in a reaction zone of the pyrolytic reactor to produce acetylene, and catalytically hydrogenating the acetylene in a hydrogenation zone to produce ethylene. In certain embodiments, the carbon efficiency is improved using methanation techniques.
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 method of combusting fuel in the combustor of a gas turbine engine is disclosed which includes injecting fuel and a first predetermined amount of airflow into the combustion chamber to form a fuel-rich, highly mixed, uniform distribution fuel-air spray pattern flowing downstream in the combustion chamber and introducing a second predetermined amount of airflow into the fuel air spray pattern from combustor air inlets positioned at a first predetermined distance downstream from the combustor dome with the first predetermined distance being greater than 0.75 times the dome height and said second predetermined amount of airflow being sufficient to cause rapid mixing and quenching of the rich fuel-air mixture to a lean fuel-air mixture. A combustor for a gas turbine engine is also disclosed which includes sidewalls and a dome wall to form a combustion chamber, a fuel injector/air swirler assembly for injecting a fuel air spray, a first and second array of air inlets for introducing airflow into the combustion chamber sufficient to cause rapid combustion and rapidly resulting lean-fuel air mixture, the first array being positioned a predetermined distance downstream from the dome wall with the predetermined distance being greater than 0.75 times the dome height and the second array of air inlets being positioned downstream from the first array.
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:
In a method of this invention, a first oxidant flow including oxygen and/or air, is injected into an exhaust gas flow from a primary burn zone in a furnace combustion chamber. The first oxidant flow is injected into the exhaust gas flow in a secondary burn zone downstream from the primary burn zone, but inside of the furnace chamber so that heat released from combustion of the first oxidant flow can be used for the purpose to which the furnace is applied. Also, the injection of the first oxidant flow into the secondary burn zone combusts fuel pollutants that might otherwise be released from the furnace into the atmosphere. The method can also include mixing a gaseous hydrocarbon fuel flow with the exhaust gas flow from the secondary burn zone to reduce the NO.sub.x, level in the exhaust gas. Also, the method can include mixing a second oxidant flow including air and/or oxygen, with the exhaust gas, preferably after reducing the NO.sub.x. If the furnace is a regenerative type, the air flow can be mixed with the exhaust gas flow in proximity to the entrance of a regenerator to heat the regenerator. The invention also includes a related system.
Abstract:
In a firing installation which is designed to minimize the pollutant emissions during the use of both a liquid and a gaseous fuel, an annular chamber (12) is arranged downstream of a first combustion stage (1) on the head side of a second combustion stage (2) arranged downstream. The first combustion stage (1) is operated as a lean stage with a burner (100), while the second combustion stage (2) is operated as a near-stiochiometric stage. The wall of the annular chamber (12) has a number of openings (13) for the inflow of a mixture (14) of recycled flue gas (4) and fuel (15). The combustion air (115) for the burner (100) is likewise a mixture (6) of air (3) and recycled flue gas (4). The hot gases from this first combustion stage (1) are moderated before entering the second combustion stage (2), self-igniting combustion taking place in this second combustion stage (2) starting from the annular chamber (12).
Abstract:
High efficiency processes for producing olefins, alkynes, and hydrogen co-production from light hydrocarbons are disclosed. In one version, the method includes the steps of combusting hydrogen and oxygen in a combustion zone of a pyrolytic reactor to create a combustion gas stream, transitioning a velocity of the combustion gas stream from subsonic to supersonic in an expansion zone of the pyrolytic reactor, injecting a light hydrocarbon into the supersonic combustion gas stream to create a mixed stream including the light hydrocarbon, transitioning the velocity of the mixed stream from supersonic to subsonic in a reaction zone of the pyrolytic reactor to produce acetylene, and catalytically hydrogenating the acetylene in a hydrogenation zone to produce ethylene. In certain embodiments, the carbon efficiency is improved using methanation techniques.