Fluid catalytic cracking process with substantially complete combustion of carbon monoxide during regeneration of catalyst

Claim 2

IN A PROCESS FOR CATALYTICALLY CRACKING PETROLEIUM FEEDSTOCK WHEREIN FLUIDIZABLE CRACKING WHICH HAS BEEN DEACTIVATED WITH COKE DEPOSITS IN WITHDRAWN FROM THE CRACKING REACTION ZONE STRIPPED OF VOLATILE MATERIAL, PASSED TO A REGENERATION ZONE, AND RECYCLED AFTER REGENERATION TO THE REACTION ZONE, THE METHOD COMPRISING: . CONTACTING DEACTIVATED, COKED CATALYST PARTICLES WITH OXYGEN-CONTAINING REGENERATION GAS TO PROVIDE AN EXCESS OF OXYGEN IN A REGENERATION ZONE AND BURNING SUBSTANTIALLY ALL OF THE COKE FROM THE CATALYST PARTICLES AT REGENERATION TEMPERATURES, B. INITIATING SUSTAINING COMBUSTION OF CARBON MOMOXIDE PRODUCE BY SAID BURNING THROUGH CONTACT WITH OXYGENCONTAINING GAS IN THE REGENRATION ZONE AT A TEMPERATURE SUFFICIENT TO COMBUST SUBSTANTIALLY ALL OF THE CARBON MONOXIDE IN THE REGENERATION ZONE BUT NOT SO HIGH THAT SAID CRACKING CATALYST IS THERMALLY DEACTIVATED, C. PROVIDING A SUFFICIENT AMOUNT OF CATALYST IN THE REGENERATION ZONE TO ABSORBED A MAJOR PORTION OF THE HEAT OF COMBUSTION IBERATED BY SAID COMBUSTION OF CARBON MONOXIDE AND TO MAINTAIN SAID CARBON MONOXIDE COMBUSTION TEMPEATURE, D. CONDUCTING SAID SUBSTANTIALLY COMPLETE COMBUSTION OF CARBON MONOXIDE IN THE REGENERATION GASES UNDERGOING COMBUSTION, WITH THE VELOCITY OF GASES IN HE REGENERATION ZONE BEING SUCH TO PROVIDE CONTACT OF SAID REGENERATION GASES WITH FLUIDIZED CRACKING CATALYST PARTICLES IN AN AMOUNT SUFFICIENT TO ABSORB A MAJOR PORTION OF THE HEAT OF COMBUSTION LIBERATED BY SAID COMBUSTION OF CARBON MONOXIDE, AND TO MAINTAIN SAID CARBON MONOXIDE COMBUSTION TEMPERATURE, E. ABSORBING SAID MAJOR PORTION OF THE HEAT OF COMBUSTION OF CARBON MONOXIDE IN SAID FLUIDIZED CRACKING CATALYST PARTICLES IN DIRECT HEAT-EXCHANGING CONTACT WITH REGENERATION GASES UNDERGOING COMBUSTION IN SAID REGENRATION ZONE AND THEREBY MAINTAINING SAID TEMPERATURE FOR COMBUSTING SUBSTANTIALLY ALL OF THE CARBON MONOXIDE IN THE REGENERATION ZONE, F. WITHDRAWING FROM THE REGENERATION ZONE EFFLUENT GAS HAVING A LOW CONTENT OF CARBON MONOXIDE, AND G. WITHDRAWING FROM HE REGENERATION ZONE REGENERATED CATALYST PARTICLES HAVING A LOW CONTENT OF RESIDUAL COKE FOR PASSAGE TO SAID REACTION ZONE.

Claim 3

The process of claim 1 wherein said cracking catalyst comprises silica, alumina and crystalline aluminosilicate.

Claim 4

The process of claim 1 wherein said combustion of carbon monoxide is at a temperature of about 1250*F. to about 1450*F.

Claim 5

The process of claim 3 wherein said withdrawn regeneration zone effluent gas contains no more than about 0.2 volume % carbon monoxide and said withdrawn regenerated catalyst particles contain no more than about 0.05 weight % coke.

Claim 6

The process of claim 4 wherein regeneration gases undergoing combustion are in contact with an amount of fluidized cracking catalyst particles sufficient to absorb greater than about 80% of the heat of combustion liberated by said combustion of carbon monoxide.

Claim 7

The process of claim 5 wherein said cracking catalyst comprises silica, alumina and crystalline aluminosilicate.

Claim 8

The process of claim 6 wherein the cracking reaction zone is in a cracking reaction vessel of the transport type.

Claim 9

IN A PROCESS FOR CATALYTICALLY CRACKING PETROLUEM FEEDSTOCK WHEREIN FLUIDIZABLE CRACKING CAALYST WHICH HAS BEEN DEACTIVATED WITH COKE DEPOSITS IS WITHDRAWN FROM THE CRACKING REACTION ZONE, STRIPPED OF VOLATILE MATERIAL, PASSED TO A REGENREATION ZONE, AND RECYCLED AFTER REGENERATION TO THE REACTION ZONE , METHOD COMPRISING: A. CONTACTING DEACTIVATED, COKED CATALYST PARTICLED WITH OXYGEN-CONTAINING REGENERATION GAS TO PROVIDE AN EXCESS OF OXYGEN IN A LOWER DENSE-PHASE CATALYST SECTION OF THE REGENERATION ZONE AND BURNING THEREIN SUBSTANTIALLY ALL OF THE COKE FROM THE CATALYS PARTICLES AT REGENERATION TEMPERATURES, B. INITIATING AND SUSTAINING COMBUSTION OF CARBON MONOXIDE PRODUCED BY SAI BURING THROUGH CONTACT WITH OXYGENCONTAINING GAS IN AN UPPER DILUT-PHASE SECTION OF THE REGENERATION ZONE TO COMBUST SUBSTANTIALLY ALL OF THE CARBON MONOXIDE REGENERATION ZONE, C. CIRCULATING FLUIDIZED REGENERATED CRACKING CATALYST PARTICLES UPWARDLY FROM SAID LOWER DENSE-PHASE SECTION INTO SAID UPPER DILUTE-PHASE SECTION IN AN AMOUNT SUFFICIENT INTO ABSORB A MAJOR PAORTION OF THE HEAT OF COMBUSTION LIBERATE BY SAID COMBUSTION OF CARBON MONOXIDE, D. ABSORBING SAID MAJOR PORTION OF THE HEAT OF COMBUSTION OF CARBON MONOXIDE IN SAID CIRCULATED FLUIDIZED REGENERATED CRACKING CATALYST PARTICLES IN DIRECT HEAT-EXCHANGING CONTACT IN SAID UPPER DILUTE-PHASE SECTION WITH SAID REGENERATION GAS, E. WITHDRAWING FROM THE REGENERATION ZNE EFFLUENT GAS HAVING A LOW CONTENT OF CARBON MONOXIDE, AND F. WITHDRAWNING FRON THE REGENERATION ZONE REGENERATED CATALYST PARTICLES HAVING A CONTENT OF RESIDUAL COKE FOR PASSAGE TO SAID REACTION ZONE

Claim 10

IN A PROCESS FOR CATALYTICALLY CRACKING PETROLUEM FEEDSTOCK WHEREIN FLUIDIZABLE CRACKING CAALYST WHICH HAS BEEN DEACTIVATED WITH COKE DEPOSITS IS WITHDRAWN FROM THE CRACKING REACTION ZONE, STRIPPED OF VOLATILE MATERIAL, PASSED TO A REGENREATION ZONE, AND RECYCLED AFTER REGENERATION TO THE REACTION ZONE , METHOD COMPRISING: A. CONTACTING DEACTIVATED, COKED CATALYST PARTICLED WITH OXYGEN-CONTAINING REGENERATION GAS TO PROVIDE AN EXCESS OF OXYGEN IN A LOWER DENSE-PHASE CATALYST SECTION OF THE REGENERATION ZONE AND BURNING THEREIN SUBSTANTIALLY ALL OF THE COKE FROM THE CATALYS PARTICLES AT REGENERATION TEMPERATURES, B. INITIATING AND SUSTAINING COMBUSTION OF CARBON MONOXIDE PRODUCED BY SAI BURING THROUGH CONTACT WITH OXYGENCONTAINING GAS IN AN UPPER DILUT-PHASE SECTION OF THE REGENERATION ZONE TO COMBUST SUBSTANTIALLY ALL OF THE CARBON MONOXIDE REGENERATION ZONE, C. CIRCULATING FLUIDIZED REGENERATED CRACKING CATALYST PARTICLES UPWARDLY FROM SAID LOWER DENSE-PHASE SECTION INTO SAID UPPER DILUTE-PHASE SECTION IN AN AMOUNT SUFFICIENT INTO ABSORB A MAJOR PAORTION OF THE HEAT OF COMBUSTION LIBERATE BY SAID COMBUSTION OF CARBON MONOXIDE, D. ABSORBING SAID MAJOR PORTION OF THE HEAT OF COMBUSTION OF CARBON MONOXIDE IN SAID CIRCULATED FLUIDIZED REGENERATED CRACKING CATALYST PARTICLES IN DIRECT HEAT-EXCHANGING CONTACT IN SAID UPPER DILUTE-PHASE SECTION WITH SAID REGENERATION GAS, E. WITHDRAWING FROM THE REGENERATION ZNE EFFLUENT GAS HAVING A LOW CONTENT OF CARBON MONOXIDE, AND F. WITHDRAWNING FRON THE REGENERATION ZONE REGENERATED CATALYST PARTICLES HAVING A CONTENT OF RESIDUAL COKE FOR PASSAGE TO SAID REACTION ZONE

Claim 11

A cyclic, continuous process for fluid catalytic cracking of petroleum hydrocarbons and catalyst regeneration, wherein active, fluidizable cracking conversion catalyst particles become spent while cracking a petroleum hydrocarbon feedstock within a cracking reaction zone, spent catalyst particles containing coke are continuously withdrawn from the reaction zone and stripped in an inert gas stream, stripped spent catalyst particles are thereafter reactivated by burning coke therefrom in a fluidized regeneration zone having a lower dense-phase section and an upper dilute-phase section, maintained at a regeneration temperature sufficiently high to effect substantially complete burning of coke, and hot regenerated cracking catalyst particles are recycled to said cracking reaction zone for use in said fluid catalytic cracking, comprising the steps of: a. introducing spent cracking catalyst particles, after stripping of residual volatile petroleum material, into a lower dense-phase section of a fluidized regeneration zone contained within a regeneration vessel and maintained at regeneration temperature; b. introducing into the lower section of said regeneration zone an oxygen-containing regeneration gas stream in an amount in excess of that required for complete combustion of the coke contained in the spent Catalyst particles and at an upward velocity sufficiently high to effect fluidization of said cracking catalyst particles; c. burning coke from the spent cracking catalyst particles in contact with said oxygen-containing regeneration gas stream in said lower section of said regeneration zone at said regeneration temperature while maintaining said catalyst particles in a dense-phase fluidized state by the upward flow of said oxygen-containing gas stream, to provide a mixture comprising fluidized regenerated cracking catalyst particles, together with oxygen, carbon monoxide and carbon dioxide; d. substantially completing the combustion of carbon monoxide in said regeneration gas stream to carbon dioxide in an upper dilute-phase section of said regeneration zone at a temperature sufficiently high to support combustion of carbon monoxide; e. circulating fluidized regenerated cracking catalyst particles upwardly from said lower section into said upper section in an amount sufficient to absorb a major portion of the heat of combustion liberated by said combustion of carbon monoxide; f. absorbing said major portion of the heat of combustion of carbon monoxide in said circulated fluidized regenerated cracking catalyst particles in direct heat-exchange contact in said upper section with said regeneration gas stream; g. separating a spent regeneration gas stream, containing carbon dioxide, excess oxygen and any unconverted carbon monoxide, from entrained catalyst particles and discharging the spent regeneration gas stream from the regeneration vessel; h. withdrawing regenerated cracking catalyst particles, substantially free of coke and conserving the absorbed heat of combustion of said carbon monoxide, from said regeneration zone and introducing said withdrawn regenerated cracking catalyst particles into the cracking reaction zone; and i. cracking a petroleum hydrocarbon feedstock with said regenerated cracking catalyst particles in said cracking reaction zone under fluidizing conditions.

Claim 12

A cyclic, continuous process for fluid catalytic cracking of petroleum hydrocarbons and catalyst regeneration, wherein active, fluidizable cracking conversion catalyst particles become spent while cracking a petroleum hydrocarbon feedstock within a cracking reaction zone, spent catalyst particles containing coke are continuously withdrawn from the reaction zone and stripped in an inert gas stream, stripped spent catalyst particles are thereafter reactivated by burning coke therefrom in a fluidized regeneration zone having a lower dense-phase section and an upper dilute-phase section, maintained at a regeneration temperature sufficiently high to effect substantially complete burning of coke, and hot regenerated cracking catalyst particles are recycled to said cracking reaction zone for use in said fluid catalytic cracking, comprising the steps of: a. introducing spent cracking catalyst particles, after stripping of residual volatile petroleum material, into a lower dense-phase section of a fluidized regeneration zone contained within a regeneration vessel and maintained at regeneration temperature; b. introducing into the lower section of said regeneration zone an oxygen-containing regeneration gas stream in an amount in excess of that required for complete combustion of the coke contained in the spent Catalyst particles and at an upward velocity sufficiently high to effect fluidization of said cracking catalyst particles; c. burning coke from the spent cracking catalyst particles in contact with said oxygen-containing regeneration gas stream in said lower section of said regeneration zone at said regeneration temperature while maintaining said catalyst particles in a dense-phase fluidized state by the upward flow of said oxygen-containing gas stream, to provide a mixture comprising fluidized regenerated cracking catalyst particles, together with oxygen, carbon monoxide and carbon dioxide; d. substantially completing the combustion of carbon monoxide in said regeneration gas stream to carbon dioxide in an upper dilute-phase section of said regeneration zone at a temperature sufficiently high to support combustion of carbon monoxide; e. circulating fluidized regenerated cracking catalyst particles upwardly from said lower section into said upper section in an amount sufficient to absorb a major portion of the heat of combustion liberated by said combustion of carbon monoxide; f. absorbing said major portion of the heat of combustion of carbon monoxide in said circulated fluidized regenerated cracking catalyst particles in direct heat-exchange contact in said upper section with said regeneration gas stream; g. separating a spent regeneration gas stream, containing carbon dioxide, excess oxygen and any unconverted carbon monoxide, from entrained catalyst particles and discharging the spent regeneration gas stream from the regeneration vessel; h. withdrawing regenerated cracking catalyst particles, substantially free of coke and conserving the absorbed heat of combustion of said carbon monoxide, from said regeneration zone and introducing said withdrawn regenerated cracking catalyst particles into the cracking reaction zone; and i. cracking a petroleum hydrocarbon feedstock with said regenerated cracking catalyst particles in said cracking reaction zone under fluidizing conditions.

Claim 13

The process of claim 9 wherein the combustion of carbon monoxide is substantially completed by controlling the temperature in the upper section of the regeneration zone at a level higher than that maintained in the lower section of the regeneration zone, while sustaining the combustion of carbon monoxide with oxygen, at least in part by adjusting the rate of curculation of regenerated cracking catalyst particles from the lower section of the regeneration zone.

Claim 14

The process of claim 9 wherein the oxygen-containing regeneration gas stream comprises air or oxygen-enriched air, flowing upwardly to provide fluidization of the lower dense-phase section of the regeneration zone, the regeneration temperature within the lower section of the regeneration zone is maintained within the range from about 1150* to about 1400*F., and the temperature within the upper section of the regeneration zone is maintained within the range from about 1200* to about 1500*F.

Claim 15

The process of claim 9 wherein the cracking catalyst particles comprise silica and alumina together with crystalline aluminosilicate.

Claim 16

The process of claim 9 wherein the cracking reaction zone is a fluidized catalytic cracking reaction zone, supplied with petroleum cracking catalyst consisting essentially of 35-89 wt. % silica, 10-50 wt. % alumina and 1-15 wt. % crystalline aluminosilicate.

Claim 17

The process of claim 9 wherein the regenerated cracking catalyst particles contain no more than about 0.05 wt. % coke and the spent regeneration gas stream contains no more than about 0.2 vol. % carbon monoxide.

Claim 18

The process of claim 9 wherein additional regenerated cracking catalyst particles are circulated upwardly from the lower dense-phase section of the regeneration zone into the upper section of the regeneration zone and dispersed within said upper section, in an amount sufficient to absorb substantially all of the evolVed heat of combustion and in response to the temperature of the dilute-phase zone.

Claim 19

The process of claim 9 wherein at least about 80% of the evolved heat of combustion of carbon monoxide is absorbed in the regenerated cracking catalyst particles and transferred therein to the cracking reaction zone.

Claim 20

The process of claim 9 wherein the burning of carbon monoxide within the upper section of the regeneration zone initiated by burning sufficient torch oil within the dense-phase zone, while additionally introducing to said zone sufficient oxygen-containing gas to afford complete combustion of the torch oil, to provide a partially spent regeneration gas passing upwardly into said upper section at a temperature sufficiently high to sustain combustion of carbon monoxide, and thereafter ceasing the combustion of torch oil.

Claim 21

The process of claim 9 wherein the burning of carbon monoxide within the upper section of the regeneration zone is initiated by momentary actuation of a spark-ignition means situated within and near the bottom of said upper section, and thereafter ceasing the spark ignition.

Claim 22

The process of claim 9 wherein the withdrawn regenerated cracking catalyst particles are introduced into the cracking reaction zone at a temperature of at least about 1,200*F.

Claim 23

The process of claim 9 wherein the regenerated cracking catalyst particles are returned to the cracking reaction zone at substantially the temperature maintained in the lower dense-phase section of the regeneration zone.

Claim 24

The process of claim 9 wherein the cracking reaction zone is contained within a cracking reaction vessel of the transport type.

Claim 25

The process of claim 9 wherein the cracking of petroleum hydrocarbon feedstock with regenerated cracking catalyst particles is effected in said cracking reaction zone under fluidizing conditions providing a cracking reaction time within the range from about 3 to about 10 seconds.

Claim 26

A cyclic, continuous process for fluid catalytic cracking of petroleum hydrocarbons and catalyst regeneration, wherein coke is burned from spent cracking catalyst particles in contact with an excess of an oxygen-containing regeneration gas stream in a fluidized dense-phase lower section of a regeneration zone and carbon monoxide from said burning of coke is further burned to carbon dioxide in a dilute-phase upper section of said regeneration zone in contact with sufficient catalyst particles to absorb most of the heat of combustion of said carbon monoxide, comprising the step of circulating additional catalyst particles into the upper section of the regeneration zone through an eductor tube situated within the regenerator vessel, said eductor tube extending substantially vertically from near the bottom of the dense-phase lower section to near the top of the dilute-phase upper section of the regeneration zone and terminating in a distributing head, the eduction of catalyst being effected with a jet stream of a gas directed upwardly into a bottom section of the eductor tube, whereby the additional catalyst particles are lifted and dispersed substantially uniformly into a top portion of the upper section of the regeneration zone.

Claim 27

A cyclic, continuous process for fluid catalytic cracking of petroleum hydrocarbons and catalyst regeneration, wherein coke is burned from spent cracking catalyst particles in contact with an excess of an oxygen-containing regeneration gas stream in a fluidized dense-phase lower section of a regeneration zone and carbon monoxide from said burning of coke is further burned to carbon dioxide in a dilute-phase upper section of said regeneration zone in contact with sufficient catalyst particles to absorb most of the heat of combustion of said carbon monoxide, comprising the step of circulating additional catalyst particles into the upper section of the regeneration zone through an eductor tube situated within the regenerator vessel, said eductor tube extending substantially vertically from near the bottom of the dense-phase lower section to near the top of the dilute-phase upper section of the regeneration zone and terminating in a distributing head, the eduction of catalyst being effected with a jet stream of a gas directed upwardly into a bottom section of the eductor tube, whereby the additional catalyst particles are lifted and dispersed substantially uniformly into a top portion of the upper section of the regeneration zone.

Claim 28

The process of claim 9 wherein spent catalyst particles and the oxygen-containing gas are introduced separately into a bottom section of the lower dense-phase section of the regeneration zone and regenerated catalyst particles are withdrawn from a top section of the lower dense-phase section of the regeneration zone.

Claim 29

The process of claim 9 wherein spent catalyst particles are first contacted with an excess of an oxygen-containing regeneration gas in the lower dense-phase section of the regeneration zone maintained at a temperature within the range from about 1,150* to about 1,400*F., and carbon monoxide is thereafter substantially completely burned to carbon dioxide within the upper dilute-phase section of the regeneration zone, at a temperature maintained within the range from about 1,200* to about 1,450*F.

Claim 30

The process of claim 25 wherein regenerated catalyst particles are withdrawn from the regeneration zone at a point near the top of the lower dense-phase section of the regeneration zone and at a temperature of about 1,250*F.

Claim 31

A cyclic, continuous process for fluid catalytic cracking of petroleum feedstock and catalyst regeneration, comprising the steps of: a. continuously feeding petroleum feedstock and regenerated fluidizable cracking catalyst particles, said catalyst particles being at a temperature of at least about 1,200*F., to a bottom section of a fluid catalytic cracking reaction vessel in weight proportions selected to provide a catalyst-oil ration within the range from about 2 to about 10; b. mixing the fluidizable cracking catalyst particles with the petroleum feedstock in said bottom section of the cracking reaction vessel, whereby the petroleum feedstock is substantially completely vaporized at a mixing temperature of about 1000*F. to provide a fluidized mixture of catalyst particles and petroleum vapors; c. passing the fluidized mixture of catalyst particles and petroleum vapors upwardly through the cracking reaction vessel at a fluidizing velocity within the range from about 20 to about 60 feet per second, whereby the cracking reaction is effected and the cracking reaction time is controlled within the range from about 3 to about 10 seconds; d. continuously withdrawing a fluidized mixture of spent catalyst particles having carbonaceous material deposited thereon and petroleum vapors, including cracked petroleum vapor products, from a top section of the cracking reaction vessel at a temperature of about 950*F., rapidly separating said spent cracking catalyst particles from said petroleum vapors, including cracked petroleum vapor products, and stripping said separated spent catalyst particles in an inert gas atmosphere at a stripping temperature of about 950*F.; e. continuously feeding stripped spent cracking catalyst particles into a lower section of a fluidized catalyst regeneration zone, contained within a catalyst regeneration vessel, together with an oxygen-containing regeneration gas in excess over the amount required for the complete combustion of the carbonaceous material deposited upon the spent cracking catalyst particles, said gas flowing at a fluidizing velocity upwardly through the regeneration zone, said fluidizing velocity being within the range from about 0.5 to about 3 feet/second; f. burning a major portion of the carbonaceous material from the spent cracking catalyst particles within the lower section of the fluidized catalyst regeneration zone at a temperature maintained within the range from about 1150* to about 1400*F., to provide a partially spent regeneration gas containing carbon monoxide; g. burning substantially all of the remaining carbonaceous material from the catalyst particles in the presence of the partially spent regeneration gas within an upper section of the fluidized catalyst regeneration zone at a temperature maintained within the range from about 1,200* to about 1, 450*F.; h. simultaneously burning substantially all of the carbon monoxide contained in the partially spent regeneration gas within the upper section of the fluidized catalyst regeneration zone at a temperature within the range from about 1,200* to about 1,450*F.; i. circulating fluidized regenerated cracking catalyst particles upwardly from said lower section into said upper section in an amount sufficient to absorb at least about 80% of the heat of combustion liberated by said burning of carbon monoxide; j. absorbing said major portion of the heat of combustion of carbon monoxide in said circulated fluidized regenerated cracking catalyst particles in direct heat-exchange contact in saiD upper section with said regeneration gas stream; k. discharging substantially spent regeneration gas, containing no more than about 2000 ppm carbon monoxide together with from about 1.0 to about 3.0 vol. % oxygen, upwardly from the fluidized regeneration zone; l. withdrawing regenerated fluidizable cracking catalyst particles, containing no more than about 0.05 wt. % carbonaceous material, from the catalyst regeneration zone at a temperature of at least 1,200*F.; and m. returning said regenerated fluidizable cracking catalyst particles, conserving at least 80% of the heat of combustion of carbon monoxide, at said temperature of at least about 1,200*F. to the bottom section of the fluid catalytic cracking reaction vessel.

Claim 32

A cyclic, continuous process for fluid catalytic cracking of petroleum feedstock and catalyst regeneration, comprising the steps of: a. continuously feeding petroleum feedstock and regenerated fluidizable cracking catalyst particles, said catalyst particles being at a temperature of at least about 1,200*F., to a bottom section of a fluid catalytic cracking reaction vessel in weight proportions selected to provide a catalyst-oil ration within the range from about 2 to about 10; b. mixing the fluidizable cracking catalyst particles with the petroleum feedstock in said bottom section of the cracking reaction vessel, whereby the petroleum feedstock is substantially completely vaporized at a mixing temperature of about 1000*F. to provide a fluidized mixture of catalyst particles and petroleum vapors; c. passing the fluidized mixture of catalyst particles and petroleum vapors upwardly through the cracking reaction vessel at a fluidizing velocity within the range from about 20 to about 60 feet per second, whereby the cracking reaction is effected and the cracking reaction time is controlled within the range from about 3 to about 10 seconds; d. continuously withdrawing a fluidized mixture of spent catalyst particles having carbonaceous material deposited thereon and petroleum vapors, including cracked petroleum vapor products, from a top section of the cracking reaction vessel at a temperature of about 950*F., rapidly separating said spent cracking catalyst particles from said petroleum vapors, including cracked petroleum vapor products, and stripping said separated spent catalyst particles in an inert gas atmosphere at a stripping temperature of about 950*F.; e. continuously feeding stripped spent cracking catalyst particles into a lower section of a fluidized catalyst regeneration zone, contained within a catalyst regeneration vessel, together with an oxygen-containing regeneration gas in excess over the amount required for the complete combustion of the carbonaceous material deposited upon the spent cracking catalyst particles, said gas flowing at a fluidizing velocity upwardly through the regeneration zone, said fluidizing velocity being within the range from about 0.5 to about 3 feet/second; f. burning a major portion of the carbonaceous material from the spent cracking catalyst particles within the lower section of the fluidized catalyst regeneration zone at a temperature maintained within the range from about 1150* to about 1400*F., to provide a partially spent regeneration gas containing carbon monoxide; g. burning substantially all of the remaining carbonaceous material from the catalyst particles in the presence of the partially spent regeneration gas within an upper section of the fluidized catalyst regeneration zone at a temperature maintained within the range from about 1,200* to about 1, 450*F.; h. simultaneously burning substantially all of the carbon monoxide contained in the partially spent regeneration gas within the upper section of the fluidized catalyst regeneration zone at a temperature within the range from about 1,200* to about 1,450*F.; i. circulating fluidized regenerated cracking catalyst particles upwardly from said lower section into said upper section in an amount sufficient to absorb at least about 80% of the heat of combustion liberated by said burning of carbon monoxide; j. absorbing said major portion of the heat of combustion of carbon monoxide in said circulated fluidized regenerated cracking catalyst particles in direct heat-exchange contact in saiD upper section with said regeneration gas stream; k. discharging substantially spent regeneration gas, containing no more than about 2000 ppm carbon monoxide together with from about 1.0 to about 3.0 vol. % oxygen, upwardly from the fluidized regeneration zone; l. withdrawing regenerated fluidizable cracking catalyst particles, containing no more than about 0.05 wt. % carbonaceous material, from the catalyst regeneration zone at a temperature of at least 1,200*F.; and m. returning said regenerated fluidizable cracking catalyst particles, conserving at least 80% of the heat of combustion of carbon monoxide, at said temperature of at least about 1,200*F. to the bottom section of the fluid catalytic cracking reaction vessel.

Claim 33

The process of claim 27 wherein the fluid catalytic cracking reaction vessel is of the transport type.

Claim 34

The process of claim 27 wherein the cracking reaction time is controlled within the range from about 3 to about 7 seconds.