Low temperature SCR moving bed flue gas denitration method for coal-fired boiler

Abstract

The invention relates to a low temperature selective catalytic reduction (SCR) moving bed flue gas denitration method for a coal-fired boiler. Boiler flue gas subjected to dust removal and a denitration reducer NH3 are introduced into a denitration reactor respectively; a low temperature SCR catalyst is continuously input from one end of the denitration reactor and continuously output from the other end of the denitration reactor to form a moving bed; the flue gas and the NH3 are in gas-solid contact with the catalyst which moves directionally in a countercurrent or crosscurrent mode in the reactor; NOx and NH3 in the flue gas are reacted with each other and the generated N2 and water vapor are discharged out of the denitration reactor along with the denitrified flue gas; in the process, parts of SO2 and NH3 in the flue gas are reacted with each other and the generated sulfate is deposited on the catalyst; and an inactivated catalyst which is continuously output from the denitration reactor enters a regenerative process, the regenerated catalyst returns to the reactor and the steps are continuously and repeatedly circulated by the method. By continuously regenerating the catalyst, the method solves the problem of catalyst poisoning and improves the denitration efficiency and running stability of a system.

Description

technical field [0001] The invention belongs to the field of air pollution control, and in particular relates to a method and a system for flue gas denitrification of a low-temperature SCR moving bed of a coal-fired boiler. 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 our country. NOx produced during coal combustion is followed by 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. With the promulgation of the domestic "Nitrogen Oxide Prevention and Control Technology Policy for Thermal Power Pla...

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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