A double-cavity mixed double-layer injection process for sncr flue gas denitrification spray gun

Abstract

Provided are an SNCR flue gas denitration spray gun and a double-cavity mixing double-layer injection technology thereof. The spray gun is composed of a central injection pipe, an outer-layer annular injection pipe, a central mixing cavity and an outer-layer mixing cavity. The spray gun is characterized in that the injection technology includes the steps that a reducing agent entering from a reducing agent conveying pipe section and compressed gas entering from a compressed gas conveying pipe section are mixed in a first mixing cavity, and most gas-liquid mixture enters the central injection pipe and is sprayed in flue gas to be treated through a central injection opening; a part of the gas-liquid mixture in the first mixing cavity enters a second mixing cavity through a one-way communicating pipe, a part of compressed air entering from the compressed air conveying pipe section does not pass through the first mixing cavity and enters the second mixing cavity directly through a communicating pipe, and a gas-liquid mixture in the second mixing cavity is sprayed in the flue gas to be treated through the outer-layer annular injection pipe. The SNCR flue gas denitration spray gun and the double-cavity mixing double-layer injection technology of the SNCR flue gas denitration spray gun have the advantages that two gas-liquid mixtures containing the reducing agent and the compressed air can be obtained by the adoption of double-cavity mixing so as to complete different spraying effects, and double layers of sleeves can prevent the two gas-liquid mixtures from influencing mutually.

Description

technical field [0001] The invention belongs to a method for purifying exhaust gas, relates to the technical field of selective non-catalytic reduction denitrification (SNCR), in particular to a double-cavity mixed double-layer injection process for a SNCR flue gas denitrification spray gun. Background technique [0002] Among the air pollutants, nitrogen oxides are a pollutant that has received great attention recently. For nitrogen oxides emitted by the cement industry and circulating fluidized beds, currently feasible technologies include selective non-catalytic reduction denitrification SNCR, selective catalytic reduction denitrification SCR and low-nitrogen burner technologies. Among them, SNCR has become the most widely used technology due to its high denitrification efficiency and low investment. [0003] For the denitrification efficiency of the SNCR process, the main influencing factors include reaction time and reaction degree, and the core process that affects th...

AI Technical Summary

Problems solved by technology

For example, the SNCR swirling atomizing spray gun with a blunt body device (public number: 103230740A), its invention improves the mixing conditions by increasing the swirling area to positively disturb the mixing conditions, and its focus is mainly on improving the mixing effect instead of improving penetration

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