Abstract: The formation mechanism of nitrogen oxide (NO_x) in catalytic cracking device was preliminarily analyzed, the factors affacting NO_x content in regeneration flue gas were discussed in detail, and the industrial test of the fast-bed - turbulent bed regeneration process was carried out. The interaction of the temperature and component content of the regenerated flue gas was analyzed, and the rule of NO_x formation in the regeneration process was summarized. Effective control of NO_x content in the regeneration flue gas was achieved by changing the process conditions such as O₂ and CO content in the regenerator and the temperature of each section of the regenerator in series. The high-efficiency and low-cost control technology of NO_x content was formed to guide the operation of regeneration process. Under the background of energy saving and emission reduction, it was expected to provide an alternative technology for reducing the pollutant emission from FCC regeneration flue gas.

Key words: catalytic cracking, fast bed-turbulent bed, regeneration process, flue gas, nitrogen oxides