Catalyst regeneration with reduced thermal damage.

摘要

Coke-contaminated catalyst particles are regenerated in a manner that achieves better utilization of oxygen and minimizes surface area loss of the catalyst by confining particles in the combustion section of a regeneration zone to a vertically elongated and tapered bed configuration. When catalyst particles move through such a regeneration zone in continuous or semi-continuous flow and simultaneously an oxygen-containing gas is passed through the particle bed in a transverse direction, combustion of the coke deposits takes place along a burn front that extends diagonally through the catalyst bed from the inlet surface of the bed to the outlet surface of the bed. Because the catalyst bed is tapered to reduce the volume of catalyst particles behind the burn wave, gas flow through the upper portion of the bed is increased and exposure of unregenerated catalyst to detrimental high temperature flue gas flowing across the bed from the burn front is minimized.