Low-temperature selective catalytic reduction (SCR) fixed bed flue gas denitrification device and method for coal-fired boiler

Abstract

The invention relates to a low-temperature selective catalytic reduction (SCR) fixed bed flue gas denitrification method and a low-temperature SCR fixed bed flue gas denitrification device for a coal-fired boiler. The method comprises the following steps of: introducing flue gas and ammonia gas serving as a denitrification reducing agent into one denitrification reactor, wherein the denitrification device is provided with more than two denitrification reactors; depositing sulfate generated by reacting SO2 in the flue gas with the ammonia gas on a catalyst to inactivate the catalyst; stopping the denitrification work of the denitrification reactor in which the catalyst is inactivated, starting another denitrification reactor for denitrification reaction, introducing regeneration gas into the denitrification reactor in which the catalyst is inactivated to regenerate the catalyst, replacing the denitrification reactor in which the catalyst is inactivated with the denitrification reactor in which the catalyst is regenerated, and recycling; and decomposing the SO2 and the ammonia gas in the regeneration process, and discharging the decomposed gas from the denitrification reactor. In order to overcome the difficulty of the conventional low-temperature SCR technology in practical application, the invention provides the low-temperature SCR device and the low-temperature SCR method for the coal-fired boiler, which are feasible and wide in application range.

Description

technical field [0001] The invention belongs to a boiler flue gas emission treatment device and method, in particular to a coal-fired boiler low-temperature SCR fixed-bed flue gas denitrification device and method. Background technique [0002] In my country's primary energy, the proportion of coal consumption is more than 70%, so coal is the main source of energy in my country. NO produced during coal combustion X is following SO 2 It is one of the important air pollutants that need to be treated urgently. In order to protect the environment and realize the sustainable development of human beings, countries around the world have formulated strict environmental protection regulations, such as the United States, Japan, Germany, etc., have formulated strict emission standards for nitrogen oxides, and stipulated strict implementation reduction plans. On July 29, 2011, China issued GB13223-2011 "Emission Standards of Air Pollutants for Thermal Power Plants", which was officia...

AI Technical Summary

Problems solved by technology

Therefore, it is difficult to achieve the performance of sulfur resistance and water resistance only by the catalyst itself, which is also the main reason why low-temperature SCR technology cannot be applied industrially.

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