Cement kiln decomposing furnace with low-nitrogen type on-line rotational flow prechamber

Abstract

The invention relates to a cement kiln decomposing furnace with a low-nitrogen type on-line rotational flow prechamber. The cement kiln decomposing furnace comprises a decomposing pipeline and a feed-end chamber which are vertically arranged, wherein the rotational flow prechamber is arranged between the decomposing pipeline and the feed-end chamber; the rotational flow prechamber is connected and communicated with the decomposing pipeline and the feed-end chamber; the rotational flow prechamber is of an involute volute shape; an air inlet is formed in the side face of the rotational flow prechamber; the air inlet is connected and communicated with the upper part of the decomposing pipeline by a tertiary air shunting device; at least two pulverized coal spray guns are also arranged on the rotational flow prechamber; and nozzles of the at least two pulverized coal spray guns stretch into an inner cavity of the rotational flow prechamber and are oppositely arranged. The invention provides the cement kiln decomposing furnace capable of effectively reducing NOx concentration in cement production waste gas.

Description

technical field [0001] The invention relates to a cement kiln decomposition furnace with a low-nitrogen on-line swirl precombustion chamber, belonging to the technical field of cement clinker calcination in a rotary kiln. Background technique [0002] During the cement production process, about 40% of the coal powder is sprayed from the burner of the rotary kiln head into the kiln for high-temperature combustion. The material melting and mineral recrystallization will only occur when the temperature of the material exceeds 1400 ° C. Usually, the kiln head The flame temperature of the burner is controlled at 1800-2200°C, so thermal NOx and fuel NOx are formed in the kiln, both of which have a relatively high proportion, of which thermal NOx is the main one. The traditional cement production waste gas denitrification technology is mainly to divert the combustion air of pulverized coal at the kiln tail to form a reduction zone in some areas of the calciner. Due to the low initi...

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Problems solved by technology

The traditional cement production waste gas denitrification technology is mainly to divert the combustion air of pulverized coal at the kiln tail to form a reduction zone in some areas of the calciner. Due to the low initial temperature, poor dispersion of coal powder and the heat absorption of raw meal powder, the It is difficult to ignite the internal pulverized coal, and the initial combustion is slow, resulting in insufficient reducing atmosphere, which is not effective in reducing the concentration of NOx in the exhaust gas, and also leads to incomplete combustion of the calciner, which increases the heat consumption of the system

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