The development of NOx reduction strategy

the fluid catalytic cracking (FCC) regeneration process and the formation and conversion of NOx are summarized. O2 is a strong inhibiter of the reaction of NO reduction by CO. It should be an efficient NOx reduction way by controlling O2 concentration of the regenerator. A new type of a multi-layer multi-zone with oxidation zone and reduction zone NOx reduction technology is proposed. This new regeneration process could have characteristics of low carbon content

short regeneration time

high burning intensity

and counter-current contact with catalyst and air. In view of NOx reduction

regeneration temperature should be less than 700℃

CO concentration in regenerator no less than 4% and O2 concentration in regenerator less than 1% at least. This novel FCC regenerator technology is a highly efficient and economical NOx reduction technology

which has been demonstrated in the FCC plant of PetroChina Dagang Petrochemical Company

and might be applied to other FCC process or coal combustion for NOx reduction.