Patent ID: 7077949

Claim:
A fluidized catalytic cracking reactor vessel comprising an upper end, a lower end and a side wall, wherein the upper end comprise: means to separate catalyst particles from an effluent of a dilute phase fluidized catalytic cracking reactor riser to produce cleaned effluent, which separation means are fluidly connected to the reactor riser at a downstream location, fluidly connected with means to discharge the cleaned effluent from the vessel and fluidly connected to means to discharge the separated catalyst to the lower end of the vessel; and, the lower end comprises: means to discharge catalyst from the reactor vessel wherein: (a) between the side wall of the vessel and the separation means a shield is preset, resulting is an exterior space between the vessel wall and the shield and an interior space within the shield, wherein the interior space is in open communication with the lower end of the reactor vessel at its lower end and wherein the exterior space and interior space are fluidly connected by means of one or more openings; and (b) means are present to supply a gas poor in coke precursors to the exterior space.