초록 ▼

The method of removing NO and NO2 from a stream of hydrocarbon combustion products at elevated temperature includes the steps: (a) removing NO from the combustion products in a first zone, and removing NO and NO2 from the combustion products in a second zone spaced downstream from the first zone, (b

The method of removing NO and NO2 from a stream of hydrocarbon combustion products at elevated temperature includes the steps: (a) removing NO from the combustion products in a first zone, and removing NO and NO2 from the combustion products in a second zone spaced downstream from the first zone, (b) the removal of NO at the first zone being effected by dispersing reagent ammonia or ammonia radical into the stream of combustion products to convert NO into N2 and H2O, and (c) the removal of NO and NO2 at the second zone being effected by providing a catalyst for contacting the stream, the catalyst effecting conversion of NO and NO2 to N2 and H2O. A natural draft heater tower is typically employed to contain the two zones.

대표청구항 ▼

The method of removing NO and NO2 from a stream of hydrocarbon combustion products at elevated temperature, the steps that include (a) providing an upright housing forming a first zone and removing NO from the combustion products flow in said first zone, and providing a stack on the housing to form

The method of removing NO and NO2 from a stream of hydrocarbon combustion products at elevated temperature, the steps that include (a) providing an upright housing forming a first zone and removing NO from the combustion products flow in said first zone, and providing a stack on the housing to form a second zone and removing NO and NO2 from the combustion products flowing in said second zone spaced downstream from said first zone, (b) the removal of NO at said first zone being effected by dispersing sufficient reagent ammonia or ammonia radical into the stream of combustion products at stream temperature between 1,300°F. and 2,000°F. to convert NO into N2 and H2O, and to provide excess unreacted reagent dispersed in said stream and carried to the second zone, (c) the removal of NO and NO2 at said second zone being effected by providing a catalyst for contacting the stream, the catalyst and excess reagent effecting conversion of NO and NO2 to N2 and H2O at stream temperatures between 400°F. and 850°F. (d) and providing first and second heat exchangers respectively in the housing and in the stack, in the flow paths of the hot combusting products, the heat exchangers operated to control said stream temperatures between 400°F. and 850°F. as aforesaid.