Kiln tail flue gas purification system and method for novel dry-process cement kiln

Abstract

The invention discloses a kiln tail flue gas purification system and method for a novel dry-process cement kiln, the kiln tail flue gas of the cement kiln first enters a preheater for heat exchange and then enters a gas conveying pipeline, a denitration reducing agent is arranged in a reducing agent storage tank, the denitration reducing agent passes through a reducing agent conveying device and ahydrolyzing device to generate ammonia gas, the ammonia gas enters the gas conveying pipeline, the flue gas discharged by the preheater enters a bag-type dust removal reactor along with the ammonia gas, and is in contact with the denitration reducing agent covering the surface of a filter bag to generate a catalytic reduction reaction when passing through the filter bag, NOx in the flue gas is reduced to N2 and H2O, the concentration of the NOx in the flue gas meets the ultra-low emission requirement, and finally the flue gas passes through a kiln tail fan and is discharged through a kiln tail chimney. The bag type dust removal reactor is used for removing dust and NOx at one time, the emission concentration reaches the ultra-low emission requirement; the operation resistance of the system is reduced by more than 50% compared with other process routes.

Description

technical field [0001] The invention relates to the field of flue gas purification, in particular to a novel dry-process cement kiln tail flue gas purification system and purification method. Background technique [0002] With the increasing environmental protection requirements, the reduction of dust and nitrogen oxides in the cement industry has become more and more important. Most of the dust problems at the kiln tail of cement plants are controlled by bag-type dust removal reactors, and the emission concentration can stably meet the ultra-low emission requirements. [0003] At present, NOx in the cement industry is mainly controlled through the SNCR process. The NOx emission concentration is much higher than the ultra-low emission requirement. In order to control the NOx emission concentration, the SNCR system will use excessive reducing agent control during actual operation. This operation mode brings many problems. , such as excessive ammonia escape, corrosion of pipe...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a kiln tail flue gas purification system and purification method of a new dry process cement kiln, which solves the discharge of pollutants such as NOx and dust in the kiln tail flue gas of a new dry process cement kiln in a large cement plant Failure to meet ultra-low emission requirements

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