FCC REGENERATION PROCESS AND APPARATUS FOR REDUCING NOX

摘要

Oxides of nitrogen (NO x) emissions from an FCC regenerator are reduced by forcing the regenerator to operate intermediate full and partial CO burn mode. Operating with less than 1 mole % O2, and up to 1 or 2 % in the flue gas, creates conditions which oxidize nitrogen compounds in coke on spent catalyst to NO x, and simultaneously convert NO x in the regenerator to nitrogen. A downstream CO boiler can burn this low CO flue gas without producing large amounts of NO x. Most NO x emissions can be eliminated. An apparatus, with the regenerator air:coke ratio controlled by both CO and O2 analyzers monitoring regenerator flue gas, is also disclosed.