A method for reducing emissions of nitrogen oxide tail gas

Abstract

The invention provides a nitrogen oxide tail gas emission reduction method. The method is characterized in that during a nitric acid production process, a Raschig ring catalyst is arranged between a platinum net and a bottom superheater of an oxidation furnace, such that nitrogen oxide in mixed gas is decomposed into nitrogen and oxygen; and the gases are cooled in subsequent processes and are applied in absorption stations. With the method provided by the invention, tail gas nitrogen oxide during the nitric acid production process can be effectively decomposed and recycled, such that environment pollution can be reduced, and a product ammonium nitrate can be recovered. The decomposition catalyst is tested and the effect thereof is analyzed. With the catalyst, NOX in nitric acid tail gas can be decomposed into nitrogen and oxygen. The environment is not polluted after nitrogen and oxygen are produced.

Description

technical field [0001] The invention relates to a method for reducing emission of nitrogen oxide tail gas, in particular to a method for reducing emission of nitrogen oxide tail gas in the production process of nitric acid. Background technique [0002] Nitric acid plant produces nitrogen oxides NO in the production process X The gas, commonly known as laughing gas, cannot be converted into useful nitrogen dioxide under normal production conditions, nor can it be absorbed by water, but is directly discharged into the atmosphere. Nitrogen oxides are one of the most powerful greenhouse gases that cause climate change. The potential value of the greenhouse effect is 310 times that of carbon dioxide. The damage to the ozone layer is more serious than Freon. It can persist in the atmosphere for 150 to 170 years. Once formed, it is not easy to disappear. . The contribution rate to global warming is 6%, and the concentration in the atmosphere has increased rapidly in recent years...

AI Technical Summary

Problems solved by technology

However, there are problems in the solution absorption method that the absorption liquid needs to be regenerated or disposed of.

[0005] The adsorption separation method is to use an adsorbent to adsorb nitrogen oxides, and then perform harmless treatment of the adsorbed nitrogen oxides. However, this method has problems such as regeneration of the adsorbent and harsh conditions for the adsorption environment.

[0006] In addition, the direct catalytic decomposition of nitrogen oxides into nitrogen and oxygen is an ideal choice, but it is difficult to find suitable catalysts to increase the reaction rate in industry

In addition, conventional catalysts are not durable to the water vapor content that often exists in industrial processes

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