Patent ID: 7435331

Claim:
A method of converting an original FCC unit of side by side configuration to a converted FCC unit for processing light feedstock comprising: replacing an original regenerator with a regenerator, comprising: a regenerator vessel housing a dense phase catalyst bed; a central upright standpipe portion for receiving the spent catalyst to be regenerated; a centerwell receiving a lower end of the standpipe portion and defining an annulus between the standpipe portion and an inside diameter of the centerwell; a valve for introducing spent catalyst through the standpipe portion into the annulus; a fuel distributor for introducing fuel into the centerwell for mixing with the catalyst in the annulus, wherein the fuel distributor is connected to a source of fuel oil; a fluidization distributor for introducing fluidization gas into the centerwell for fluidizing the catalyst in the annulus, wherein the fluidization distributor is connected to a source of a fluidization gas; a radial slot formed in the centerwell below an upper surface of the dense phase bed for introducing the catalyst and fuel mixture from the annulus into the dense phase bed below an the upper surface; an air distributor disposed in the dense phase bed subjacent to the radial slot for introducing combustion air into the dense phase bed; a catalyst discharge outlet in fluid communication with the dense phase bed; and an off gas discharge outlet in fluid communication with a dilute phase above the dense phase bed; introducing a spent catalyst through the standpipe portion into the centerwell; introducing a fuel oil through the fuel distributor into the centerwell; mixing the spent catalyst and the fuel oil within the centerwell; introducing a fluidization gas into the centerwell through the fluidization distributor to provide a fluidized catalyst and fuel mixture; introducing the catalyst and fuel mixture into the dense phase bed through the radial slot; introducing combustion air through the air distributor into the dense phase bed; and combusting at least a portion of the fuel oil and the spent catalyst to provide carbon dioxide and the regenerated catalyst.