Method and apparatus for removing sulfur oxides and/or nitrogen oxides from catalytic cracking regeneration flue gas

Abstract

The invention relates to a method and an apparatus for removing sulfur oxides and / or nitrogen oxides from catalytic cracking regeneration flue gas. The method comprises that in a catalytic cracking regenerator, a desulfurization and denitration auxiliary agent and a catalytic cracking catalyst contact flue gas at a temperature of 650-750 DEG C to remove sulfur oxides and nitrogen oxides from the flue gas; one part of the mixture after the reaction is introduced into a catalytic cracking reactor; the other part of the mixture after the reaction is introduced into an auxiliary agent regenerator,and reacts with reducing gas at a temperature of 450-650 DEG C so as to be regenerated; and the gas-solid stream in the auxiliary agent regenerator is subjected to gas-solid separation, the separatedgas phase is subjected to further subsequent treatment, and the separated regenerated desulfurization and denitration auxiliary agent and the catalytic cracking catalyst return to the catalytic cracking regenerator so as to be recycled. According to the present invention, with the method, the regeneration depth of the spent desulfurization and denitration auxiliary agent is enhanced by the auxiliary agent regenerator so as to ensure the flue gas treatment effect and prolong the service life of the auxiliary agent; and compared with the newly constructed flue gas treatment device, the apparatus of the present invention can simplify the process, easily improve the utilization efficiency of heat energy and pressure, and save the equipment investment.

Description

technical field [0001] The invention relates to a method for removing pollutants in industrial flue gas, more specifically, relates to a method for removing sulfur oxides in industrial flue gas at high temperature, and belongs to the technical field of flue waste gas comprehensive treatment. Background technique [0002] The methods to control the sulfur emission from fluidized catalytic cracking regeneration flue gas mainly include the selection of high-quality crude oil, raw material pretreatment, flue gas treatment and sulfur oxides (SO for short). x ) transfer technology. [0003] Based on source and cost considerations, refineries have little choice for crude oil; raw material pre-hydrogenation and flue gas treatment need to increase equipment construction costs, high energy consumption, high operating costs, but strong applicability, good investment economy, suitable for processing High sulfur crude oil; the use of sulfur oxide transfer agent can control SO in FCC flu...

AI Technical Summary

Problems solved by technology

[0005] Due to the mixed use, the sulfur transfer agent goes through the same path as the catalytic cracking catalyst, which is tested in the cycle between oxidizing atmosphere and reducing atmosphere: the sulfate formed on the sulfur transfer agent in the regenerator with high temperature and oxidizing atmosphere needs to have Good stability; when the mixture enters the reducing atmosphere, the reaction involving sulfate is only one of the many reactions involving multi-carbon number hydrocarbon cracking, isomerization, condensation, polycondensation, etc., involving sulfate and The reduction reaction of metal sulfide is not complete, and the result of long-term accumulation will lead to the failure of the sulfur transfer agent and the dosage of the transfer aid

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