Coke oven flue gas denitration process and system

Abstract

The invention discloses a coke oven flue gas denitration process and system. The process comprises the following steps: making coke oven flue gas come into contact with an NO catalytic oxidant to oxidize a part of NO into NO2; mixing mixed gas of ammonia vapor and the air with the coke oven flue gas being subjected to catalytic oxidation; making the mixed coke oven flue gas come into contact witha low-temperature NH3-SCR denitration catalyst, and performing a catalytic reaction on NH3, O2 and NOx to generate N2 and H2O. The system comprises an NO catalytic oxidation tower, a gas mixing systemand a denitration and ammonia removal tower, wherein the coke oven flue gas enters the NO catalytic oxidation tower, and a part of NO is oxidized into NO2; the gas mixing system firstly mixes ammoniavapor with the air, and then mixes the mixed gas with the coke oven flue gas which is subjected to catalytic oxidation and is discharged out of the NO catalytic oxidation tower; the mixed coke oven flue gas is fed into the denitration and ammonia removal tower for denitration and ammonia removal. The process has the advantages of low cost, high efficiency, simple process flow and the like. The system has the advantages of simple structure, low energy consumption, low maintenance cost and the like.

Description

technical field [0001] The invention belongs to the technical field of flue gas purification, and in particular relates to a coke oven flue gas denitrification process and a coke oven flue gas denitrification system. Background technique [0002] In recent years, smog has frequently appeared in most areas of our country. The country has paid more and more attention to environmental protection (air pollution), and the emission standards have become more and more stringent. The emission standards of coke ovens in some areas have required: SO 2 Less than 30mg / Nm 3 ;NOx less than 150mg / Nm 3 ; Dust less than 15mg / Nm 3 . Current SO in coke oven 2 , NOx content can not meet the emission requirements, so adding coke oven flue gas denitrification device is a problem that coking units must consider. [0003] At present, my country's denitrification devices are mainly used in power plants, which are mainly divided into in-combustion denitrification and post-combustion denitrificat...

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Problems solved by technology

[0010] b) If it is arranged after desulfurization, the temperature of the flue gas is low and cannot meet the temperature requirements of the alum-based catalyst, so it needs to be heated up and equipped with a heating furnace, and the energy consumption is high

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