Apparatus for regeneration of spent cracking catalyst

In apparatus embodying a spent, coked catalyst regenerator as used in combination with a hydrocarbon conversion reactor, each of which can contain a dense phase bed of fluidized catalyst, wherein hydrocarbons can be converted within said reactor at reaction conditions by contact with the dense phase bed of the said catalyst, the catalyst in said reactor becoming gradually deactivated by the formation of coke on the catalyst, and the catalyst transported from the reactor to said regenerator wherein coke is burned from the coked catalyst and reactivated by means which include

• a spent, coked catalyst standpipe through which spent, coked catalyst is conveyed from the reactor to the catalyst regenerator,
• a spent, coked catalyst riser operatively communicated with said spent, coked catalyst standpipe for receipt of coked catalyst therefrom, and into which air is injected to transport said catalyst, and introduce at least a portion of the air requirements into said dense phase fluidized catalyst bed of the spent, coked catalyst regenerator for regeneration of same by burning coke from the catalyst,
• a regenerated catalyst standpipe outlet for recycle of regenerated catalyst via a regenerated catalyst riser to the reactor,
• the improvement comprising
• a conduit communicated with said spent, coked catalyst riser extending into the lower end of said regeneration vessel, the wall of the conduit surrounding said regenerated catalyst standpipe outlet forming an annulus through which spent, coked catalyst and air can be passed into the dense phase fluidized bed of said regenerator,
• disc and doughnut shaped gas distributors circumferentially dispersed about the inside wall of said conduit and along the outside wall of said regenerated catalyst standpipe outlet forming said annulus to aid in creating a more uniform flow of air and catalyst into the dense phase fluidized bed of said regenerator, and
• a radial distributor plate located within said regenerator adjacent to the terminal end of said annulus, the distributor plate lying within the path of the spent, coked catalyst and transporting air entering into the regenerator and against which the spent, coked catalyst and air are impinged and substantially uniformly dispersed outwardly within the dense phase fluidized bed of the regenerator.