Denitration device between kiln tail smoke chamber of cement kiln and decomposing furnace

Abstract

The invention discloses a denitration device between a kiln tail smoke chamber of a cement kiln and a decomposing furnace. A re-combustion area is arranged between the kiln tail smoke chamber and the decomposing furnace, the reduction combustion retention time of pulverized coal in the re-combustion area is 1-2 s, a top end opening of the re-combustion area shrinks inwards and forms a temperature control necking opening, and the air speed passing through the temperature control necking opening is 14-22 m / s. The reduction combustion retention time of the re-combustion area is obviously prolonged, and the retention time of reduction combustion of a conventional staged combustion system is generally less than 0.4 s. The temperature control necking opening can effectively prevent upper materials from entering the re-combustion area, and the situation that the temperature of the area is reduced after the materials enter the re-combustion area, and consequently the reduction reaction efficiency is reduced is avoided. A lower material pipe and a middle material pipe serving as an alternative scheme are also beneficial to accurately controlling the temperature of the re-combustion area, it is guaranteed that the situations of local high temperature and skinning do not occur in the area, the working temperature is as high as possible, and the NOx reduction efficiency is improved easily.

Description

Technical field: [0001] The invention relates to a denitrification device between a cement kiln tail smoke chamber and a decomposition furnace. Background technique: [0002] The staged combustion denitrification system is to reduce the NOx emission of the cement kiln through the control of the combustion process. 2 and CH i and other gas components to form a strong reducing atmosphere, which can reduce NOx in the exhaust gas of the kiln tail flue chamber to N 2 . [0003] The residence time of reducing combustion in the oxygen-deficient combustion zone of the existing staged combustion denitrification system is generally less than 0.4s. The reduction combustion residence time is short, and the materials in the decomposition furnace are easy to enter the oxygen-deficient combustion zone, which reduces the efficiency of the reduction reaction. Invention content: [0004] The present invention provides a denitrification device between the tail smoke chamber of a cement ki...

AI Technical Summary

Problems solved by technology

[0003] The residence time of reducing combustion in the oxygen-deficient combustion zone of the existing staged combustion denitrification system is generally less than 0.4s. The reduction combustion residence time is short, and the materials in the decomposition furnace are easy to enter the oxygen-deficient combustion zone, which reduces the efficiency of the reduction reaction.

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