Internal method for reducing transverse oxygen gradients in FCCU regeneration

摘要

A minor portion of the regeneration gas used to regenerate spent fluid catalytic cracking catalyst is introduced into the regeneration zone in the localized area of the terminus of the spent catalyst line so as to combust the volatile hydrocarbons in mixture with the spent catalyst being transferred from the reaction zone to the regeneration zone. This serves to reduce and/or minimize transverse oxygen gradients in both the dense phase catalyst bed and in the effluent gases therefrom such that excessive or undesirable afterburning in the dilute catalyst phase can be minimized or eliminated.