Method for regenerating fluidizable solid particles employed in hydrocarbon conversion

Claim 1

In a fluid catalyst operation comprising conversion of hydrocarbons to lower and higher boiling products and regeneration of catalyst employed in said hydrocarbon conversion, the method for regenerating catalyst particles comprising carbonaceous material deposits which comprises passing spent catalyst into an annular catalyst regeneration zone about the periphery of an inner concentric catalyst regeneration zone, admixing hot freshly regenerated catalyst particles obtained from said concentric zone with said spent catalyst in said annular zone in an amount sufficient to raise the temperature of said spent catalyst to a temperature promoting the combustion of carbonaceous material in the presence of oxygen containing regeneration gas, causing said mixture of spent and regenerated catalyst to flow as a suspension in combustion supporting gases generally upwardly through vertical sections of said annular zone during combustion of carbonaceous material with controlled amounts of introduced combustion supporting gas, discharging the suspension from the top of said annular zone through an annular passageway into a dispersed phase of catalyst above said concentric catalyst regeneration zone for flow generally downwardly therethrough as a dense flowing bed of catalyst and countercurrent to rising regeneration gas, introducing combustion supporting regeneration gas to a bottom portion of said concentric downwardly flowing bed of catalyst beneath the inlet of a regeneration catalyst withdrawal zone, passing regenerated catalyst from a lower portion of said concentric bed through said withdrawal zone to a hydrocarbon conversion zone, separating particles of catalyst from combustion gases in said dispersed phase above said concentric bed of catalyst, withdrawing said combustion gases and passing catalyst separated in said dispersed phase into said concentric bed.