초록 ▼

Temperature rise during the exothermic reduction of nitrogen oxides contained in a carbon dioxide-rich gas stream to nitrogen by contacting the gas stream with ammonia in a reactor containing a reduction catalyst is controlled by recycling a portion of the gaseous effluent from the reactor to the ga

Temperature rise during the exothermic reduction of nitrogen oxides contained in a carbon dioxide-rich gas stream to nitrogen by contacting the gas stream with ammonia in a reactor containing a reduction catalyst is controlled by recycling a portion of the gaseous effluent from the reactor to the gas stream prior to its introduction into the reactor, thereby cooling the reactor contents without diluting the carbon dioxide in the effluent.

대표청구항 ▼

[ What is claimed is:] [1.] In a process for removing NOX from a gas stream containing the NOX as an impurity comprising contacting the gas stream and ammonia in a reaction zone containing a catalyst which effects the reaction of NOX with ammonia to produce a product gas containing nitrogen and wate

[ What is claimed is:] [1.] In a process for removing NOX from a gas stream containing the NOX as an impurity comprising contacting the gas stream and ammonia in a reaction zone containing a catalyst which effects the reaction of NOX with ammonia to produce a product gas containing nitrogen and water vapor, the improvement comprising continuously recycling a portion of the product gas to the gas stream thereby diluting the NOX in the gas stream sufficiently to prevent the temperature of the gas stream in the reaction zone from rising to the point at which significant deactivation of the catalyst occurs at any time during the process.