Abstract: The present invention relates to a process for production of high yield of hydrogen by carrying out the dry reforming of the dry gas generated from the process itself by utilizing the same catalyst for cracking and producing high yield of light olefins such as ethylene, propylene and butylenes from residue feedstocks.

Abstract: The present invention relates to a device and to a process for the fluidized bed catalytic cracking of a hydrocarbon feedstock, in which: a first feedstock (2) is cracked in a dense fluidized bed reactor (1) in the presence of a catalyst (3) to produce a first effluent; and at least one second feedstock (10) is cracked in a transport fluidized bed reactor (4) in the presence of the catalyst (3) supplied by the dense fluidized bed reactor (1) to produce a second effluent, the second feedstock (10) being a heavier feedstock than the first feedstock (2).

Abstract: Processes for upgrading a hydrocarbon. The process can include contacting a hydrocarbon-containing feed with fluidized catalyst particles that can include a Group 8-10 element or a compound thereof disposed on a support to effect one or more of dehydrogenation, dehydroaromatization, and dehydrocyclization of at least a portion of the hydrocarbon-containing feed to produce a coked catalyst and an effluent. The process can also include contacting at least a portion of the coked catalyst particles with an oxidant to effect combustion of at least a portion of the coke to produce regenerated catalyst particles. The process can also include contacting an additional quantity of the hydrocarbon-containing feed with at least a portion of the regenerated catalyst particles to produce additional effluent and re-coked catalyst particles.

Abstract: According to one or more embodiments disclosed herein, a system component of a fluid catalytic reactor system may include a catalyst separation section, a riser, and a reactor vessel. The catalyst separation section may include separation section walls defining an interior region of the catalyst separation section, a gas outlet port, a riser port, a separation device, and a catalyst outlet port. The riser may extend through the riser port of the catalyst separation section and include an external riser section and an internal riser section. The reactor vessel may include a reactor vessel inlet port, and a reactor vessel outlet port in fluid communication with the external riser section of the riser.

Abstract: A process for combusting coke from catalyst in partial burn mode is disclosed. The partial burn regenerator runs deprived of oxygen such that the flue gas will contain a fair amount of carbon monoxide. The oxygen present in the flue gas can burn in the bed before reaching the dilute phase. The catalyst distributor is positioned in the upper chamber of the regeneration vessel for discharging the catalyst.

Abstract: A reaction-regeneration device for catalytic dehydrogenation or/and catalytic cracking of alkanes comprises a reaction device and a regeneration device. The reaction device comprises a reactor and a disengager, and the disengager is located at an upper part of the reactor. The reactor comprises a tapering section, and diameters of cross sections of the tapering section gradually decrease from bottom to top. Secondary conversion of alkenes caused by back-mixing is reduced, and thus the yield and selectivity to alkenes are increased.

Abstract: A reaction-regeneration device for catalytic dehydrogenation or/and catalytic cracking of alkanes comprises a reaction device and a regeneration device. The reaction device comprises a reactor and a disengager, and the disengager is located at an upper part of the reactor. The reactor comprises a tapering section, and diameters of cross sections of the tapering section gradually decrease from bottom to top. Secondary conversion of alkenes caused by back-mixing is reduced, and thus the yield and selectivity to alkenes are increased.

Abstract: A catalyst is provided for production of monocyclic aromatic hydrocarbons having a carbon number of 6 to 8 from feedstock in which a 10 vol % distillation temperature is 140° C. or higher and a 90 vol % distillation temperature is 380° C. or lower. The catalyst contains crystalline aluminosilicate including large-pore zeolite having a 12-membered ring structure, and intermediate-pore zeolite having a 10-membered ring structure.

Abstract: Apparatuses and methods for separating regenerated catalyst are provided. In one embodiment, an apparatus for separating regenerated catalyst includes a regeneration vessel including a catalyst bed section. The apparatus includes a catalyst settler physically separated from the catalyst bed section by a wall extending within the regeneration vessel. The catalyst overflowing the catalyst bed section flows over the wall and enters the catalyst settler. The apparatus further includes a pipe in fluid communication with the catalyst settler and configured to deliver regenerated catalyst from the regeneration vessel to another vessel.

Abstract: A process gas preparation device for an industrial furnace system is disclosed. The gas preparation device includes a preparation reactor having a catalyst. A gas feed line and a gas return line are connected between the industrial furnace and the preparation reactor to form a closed loop. A compressor is situated upstream from the preparation reactor in the feed line. The preparation reactor is also connected with supply lines for hydrocarbon gas and air to be supplied to the preparation reactor. The process gas preparation device also includes a control device with which process gas preparation and return can be regulated and controlled. The gas feed line also has a shut-off valve. The control device can check the functional state of the catalyst by measuring the pressure differential across the catalyst and can initiate a burn-out process therein to clear clogging of the catalyst.

Abstract: Systems and methods for dehumidifying and conditioning air for a commercial building are presented. In one instance, a system involves ventilating a building at a rate higher than the required outdoor airflow rate in order to compensate for the fan being turned off when the compressor is off. Other systems and methods are presented.

Abstract: A fluidized bed gasification furnace includes a control device that identifies a defective fluidization spot of a fluidized bed based on distribution of temperatures detected by a plurality of temperature sensors, temporarily increases an amount of supplied combustion gas to air boxes located below the identified defective fluidization spot, and increases a speed of discharge of noncombustibles and a fluidization medium discharged by an extruder.

Abstract: A water-containing solid fuel drying apparatus that can efficiently dry with low energy consumption by effectively utilizing sensible heat and latent heat of a heating medium for drying, etc. is provided.

Abstract: The invention belongs to energy chemical technical field, especially relates to a fluidized bed reactor and a method for preparation of polyoxymethylene dimethyl ethers from dimethoxymethane and paraformaldehyde. The fluidized bed reactor comprises a gas inlet, a gas distributor, a catalyst inlet, a gas outlet, a fluid inlet, a catalyst outlet, a bottom component and an interstage component, a bottom component related gas upward channel, an interstage component related gas upward channel, a fluid outlet, a bottom downcomer and an interstage downcomer.

Abstract: The present invention relates to a method for the production of ethene, CO, and hydrogen in a reactor with a circulating fluidized bed with two independent sections, from feedstocks that contain hydrocarbons with at least 11 carbon atoms or from feedstocks with a high oxygen content, using a catalyst in particulate form. The method teaches that in one of the sections of the reactor, in the absence of oxygen, a catalyst containing a dehydrogenation metal promotes the cracking of the said feedstocks, facilitating the subsequent endothermic reactions. In the other section, the coke is burned with air and the heating of the catalyst is controlled, for the adjustment of the appropriate amount of energy that the heated catalyst will convey to the section in which the endothermic reactions take place. The total ethene yield of the process according to the present invention is approximately 20% by weight in relation to the feedstock.

Abstract: Hydrocarbon feed to a catalytic reactor can be heat exchanged with flue gas from a catalyst regenerator. This innovation enables recovery of more energy from flue gas thus resulting in a lower flue gas discharge temperature. As a result, other hot hydrocarbon streams conventionally used to preheat hydrocarbon feed can now be used to generate more high pressure steam.

Abstract: The production of light hydrocarbons consisting of ethylene, propylene, butylenes, and of gasoline is enhanced by introducing a heavy oil feedstream derived from an external source into an ancillary downflow reactor that utilizes the same catalyst composition as an adjacent FCC unit for cracking the heavy oil and withdrawing the desired lighter hydrocarbon reaction product stream from the downflow reactor and regenerating the catalyst in the same regeneration vessel that is used to regenerate the spent catalyst from the FCC unit. The efficiency of the recovery of the desired lighter olefinic hydrocarbons is maximized by limiting the feedstream to the downflow reactor to heavy oils that can be processed under relatively harsher conditions, while minimizing production of undesired by-products.

Abstract: A process for mixing regenerated and carbonized catalyst involves obstructing upward flow of catalyst by one or more baffles between a catalyst inlet and a feed distributor. Each catalyst stream may be passed to opposite sides of a riser. Baffles obstruct upward flow to effect mixing of regenerated and carbonized catalyst to obtain a more uniform temperature and catalyst mixture before contacting the feed.

Abstract: In a hybrid vehicle, control is executed to operate an engine with fuel injection being performed, when an unexecuted percentage of catalyst degradation suppression control is equal to or greater than a threshold value of the unexecuted percentage, when a power storage percentage of a battery is equal to or greater than a threshold value of the power storage percentage and the battery is charging, and also when a vehicle speed is equal to or greater than a threshold value of the vehicle speed and a cumulative air amount is equal to or greater than a threshold value of the cumulative air amount, when a catalyst temperature is less than a first threshold temperature and equal to or greater than a second threshold temperature, when the catalyst temperature is equal to or greater than the first threshold temperature, when there is a braking request while the engine is operating.

Abstract: A reactor design and process for the dehydrogenation of hydrocarbons is presented. The reactor design includes a multibed catalytic reactor, where each of the reactor beds are fluidized. The catalyst in the reactor cascades through the reactor beds, with fresh catalyst input into the first reactor bed, and the spent catalyst withdrawn from the last reactor bed. The hydrocarbon feedstream is input to the reactor beds in a parallel formation, thereby decreasing the thermal residence time of the hydrocarbons when compared with a single bed fluidized reactor, or a series reactor scheme.

Abstract: Disclosed is an FCC apparatus and process in which coked catalyst is recycled to the base of the riser to contact fresh feed through a passage disposed within the riser.

Abstract: Disclosed is a catalyst distributor and process for spreading catalyst over a regenerator vessel. Nozzles disposed angular to a header of the distributor spread catalyst throughout a full cross section of the catalyst bed.

Abstract: This invention is directed to a method and apparatus for regenerating a catalyst used in an FCC unit, including providing a spent catalyst into an upper portion of a regenerator, maintaining a calcination phase, a gasification phase, and a combustion phase of fluidized catalyst in the regenerator, combusting carbon in the combustion phase and producing a combustion flue gas, reacting carbon in the gasification phase with the combustion flue gas to form a carbon monoxide rich flue gas, and calcining the spent catalyst with the carbon monoxide rich flue gas.

Abstract: An apparatus and process for partially upgraded heavy oil diluent production. A crude heavy oil and/or bitumen feed is supplied to an FCC unit having a low activity catalyst and low conversion number. A distillate fraction is supplied for use as diluent to end users. The distillate fraction and FCC unit gas oil products can be supplied to a hydrotreater for upgrading and collected as a synthetic crude product stream. An asphaltene fraction can be supplied to a gasifier for the recovery of power, steam and hydrogen, which can be supplied to the hydrotreater or otherwise within the process or exported.

Abstract: A reactor for hydrolytic splitting of cellulose under high pressure and heat has an inlet and outlet each with a cross-sectional area smaller than the cross-sectional area of the reactor. The pressure and heat in the reactor forms a cellulose plug within the inlet and the outlet. The inlet plug stops cellulose from escaping out the inlet. Cellulose begins to breakdown under heat, pressure, and if required an acid or a lubricant. The outlet plug slows downstream movement of cooking cellulose. Cellulose may be pre-treated by the addition of water, a weak acid, a lubricant, or a combination of the foregoing. The outer surface of the plug cooks faster than the inner core of the plug, becomes a liquefied slurry, and slides faster towards the outlet than the inner core.

Abstract: A process and device to optimize the yield of fluid catalytic cracking products through a reactive stripping process are disclosed. One or more hydrocarbon streams (3) are introduced in an intermediary region of the stripper (1) of a fluid catalytic cracking unit (FCC), from a device that allows a homogeneous distribution with adequate dispersion. This/these stream(s) react(s) with the catalyst of FCC, although its activity is reduced due to the adsorption of hydrocarbons in the reaction zone, generating products that improve and/or change the global distribution of products, providing a refinery profile adequate to meet quality demands and requirements.

Abstract: Methods and systems of processing a hydrocarbonaceous feed stock flows are provided. In one aspect, the method includes providing two or more hydroprocessing stages disposed in sequence, each hydroprocessing stage having a hydroprocessing reaction zone with a hydrogen requirement and each stage in fluid communication with the preceding stage. A hydrogen source is provided substantially free of hydrogen from a hydrogen recycle compressor. The hydrocarbonaceous feed stock flow is separated into an portions of fresh feed for each hydroprocessing stage, and then supplying the first portion of fresh feed with hydrogen from the hydrogen source in an amount satisfying substantially all of the hydrogen requirements of the hydroprocessing stages to a first hydroprocessing zone.

Abstract: Disclosed is a process for making middle distillate and lower olefins. The process includes catalytically cracking a gas oil feedstock within a riser reactor zone by contacting under suitable catalytic cracking conditions within the riser reactor zone the gas oil feedstock with a middle distillate selective cracking catalyst that comprises amorphous silica alumina and a zeolite to yield a cracked gas oil product and a spent cracking catalyst. The spent cracking catalyst is regenerated to yield a regenerated cracking catalyst. Within an intermediate cracking reactor such as a dense bed reactor zone and under suitable high severity cracking conditions a gasoline feedstock is contacted with the regenerated cracking catalyst to yield a cracked gasoline product and a used regenerated cracking catalyst. The used regenerated cracking catalyst is utilized as the middle distillate selective catalyst.

Abstract: A method is provided for introducing or reintroducing a gas into a slurry vessel holding a slurry comprising a liquid and solid particles and having a gas distributor for injecting a gas into the slurry, where the gas distributor includes a sparger device comprising an apertured sparger portion inside the slurry vessel, an inlet portion leading into the slurry vessel and an outlet portion leading from the slurry vessel, and a valve, external of the slurry vessel, operable to allow or deny flow from the sparger portion out through the outlet portion of the sparger device. The method comprises operating the valve to allow flow through the outlet portion of the sparger device, flushing the sparger device through the outlet portion to remove settled material which may be present in the sparger device, operating the valve to deny flow through the outlet portion of the sparger device, and introducing or reintroducing the gas into the slurry vessel through the sparger device.

Abstract: A fines injection apparatus, a fluid catalytic cracking (FCC) system having a fines injection apparatus, and a method for using the same are provided. In one embodiment, a FCC system includes a FCC unit, a fines collector, and a fines injector coupled to the fines collector for retuning the fines recovered in the fines collector to the FCC unit. In another embodiment, an apparatus for injecting fines into a FCC system includes a fines separator coupled to an effluent stream and an injection apparatus coupled to a regenerator. A conduit is provided for delivering collected fines from the fines separator to the injection apparatus. In yet another embodiment, a method for injecting fines into FCC system includes collecting fines from a waste stream of a FCC system, automatically transferring the collected fines to a fines injection apparatus, and periodically injecting the transferred fines into the FCC system.

Abstract: Method of metering at least one solid, particulate catalyst into a reactor containing a fluidized bed (11) of particles in an at least partly gaseous medium, in which the catalyst is metered discontinuously at prescribed time intervals into the fluidized bed (11) at at least one metering point (10). According to the present invention, a fluid stream is firstly introduced into the reactor (5) so that a region having a reduced particle density is formed in the fluidized bed (11) around the metering point (10) and the catalyst is subsequently metered into this region. As a result of the prior introduction of a fluid stream (“preblowing”) before the actual introduction of the catalyst, the catalyst can penetrate significantly deeper into the fluidized bed from the metering point due to the reduced particle density and is dispersed better.

Abstract: A dual riser FCC process is disclosed wherein first and second hydrocarbon feeds (5, 6) are supplied to the respective first and second risers (2, 4) to make an effluent rich in ethylene, propylene and/or aromatics. Where the hydrocarbon feeds are different, the respective risers can have different conditions to favor conversion to ethylene and/or propylene. A minor amount of a coke precursor (80, 82) can be added to one or both of the hydrocarbon feeds (5, 6) to reduce or eliminate the amount of supplemental fuel needed to heat balance the system. The different feeds, including the coke precursor and any recycle streams (36, 44) can be segregated by type to improve olefin yields, including an embodiment where the paraffinic feeds are supplied to one riser and the olefinic feeds to the other.

Abstract: Self purging expansion joint can include first annular seal sleeve connecting bellows to first conduit and second annular seal sleeve connecting bellows to second conduit. Flow-restricting orifice(s) can allow a higher pressure external fluid to flow through the annular passage to purge the bellows and into the primary fluid flow passage of the expansion joint containing a lower pressure fluid. Self purging expansion joint can be utilized in a disengager vessel of a fluid catalytic cracking (FCC) unit, for example, between primary and secondary stripping cyclones.

Abstract: A process for upgrading a residua feedstock using a short vapor contact time thermal process unit comprised of a horizontal moving bed of fluidized hot particles. The residua feedstock is preferably atomized so that the Sauter mean diameter of the residua feedstock entering the reactor is less than about 2500 ?m. One or more horizontally disposed screws is preferably used to fluidize a bed of hot particles.

Abstract: A fluidized-bed reactor is disclosed. The fluidized-bed reactor steadies the gas flow through the fluidized bed chamber of the reactor. The swirl chamber of the reactor consists of a conical housing in which a conical insert is also situated. This creates an annular gap between the housing and the insert, which acts as the swirl chamber and which, according to the geometry of the two components, causes a velocity of the gas flow which remains the same along the height, which increases or which decreases. Such a reactor can also be called a constant annular-gap reactor.

Abstract: A stripping apparatus for desorbing gases from solid particles through which flows counter-currently a stripping fluid is described, which comprises a series of sets of at least two parallel, segmented, baffle plates each, with the segmented baffles being oriented so that the rows are offset relative to rows of other levels, where the thickness and separation of said sets of baffles is so dimensioned as to reduce coalescence of the size of the formed bubbles and optimize the hydrocarbons desorption from said fluidized solid particles. The solid particles are mainly spent catalyst particles from a FCC process. The stripping process to be carried out in a fluidized bed comprises contacting the spent catalyst with a stripping fluid that flows upwardly in the fluidized bed in the form of bubbles. Adsorbed hydrocarbons present in the spent catalyst are transferred from the catalyst emulsion that flows downwardly to the upwardly moving bubbles, so as to promote the efficient recovery of cracked products.

Abstract: Disclosed is an apparatus and process for controlling space velocity in a fluidized catalytic conversion reactor. The catalyst flux rate can be adjusted during the process of the reaction to adjust the space velocity and maintain a fast fluidized flow regime therein. The set parameter in the reactor may be pressure drop which is proportional to catalyst density.

Abstract: A cooling method of a hydrotreating plant having a desulfurization section (1) including a furnace (12) for heating liquid to be processed, reactors (14, 15) for hydrotreating sulfur to generate hydrogen sulfide, a hydrogen sulfide absorber (19) for absorbing the hydrogen sulfide generated in the reactors (14, 15), and a compressor (21) for compressing and transferring fluid from the hydrogen sulfide absorber (19) toward the reactors (14, 15), the cooling method comprising the steps of gradually depressurizing the hydrotreating plant at the desulfurization section (1) to a pressure level at which reactor material does not embrittle and gas does not leak due to difference of mechanical thermal expansion in the plant after stopping supply of the liquid to be processed, operating the compressor (21) approximately at the maximum rotation number, and completely extinguishing burners (12A, 12B) in the furnace (12) during plant shutdown operation.

Abstract: A shelf is incorporated into a typical FCC riser that permits the tips of the nozzles to extend past the wall of the riser while preventing the tips from promoting coke build-up and protecting the tips from erosion. The shelf can be part of an angled section that often appears in a transition zone for increasing the internal diameter of the riser to accommodate the volumetric expansion of the feed. The shelf section reduces the non-uniformity in the mixing of the catalyst and feed and minimizes backmixing of the feed injection. The shelf of this invention accomplishes these objectives without recessing the feed injectors into the riser wall which can interfere with the spray pattern.

Abstract: A baffle-style stripper for an FCC process comprising sloped baffles in which a greater volumetric flow rate of stripping medium permeates openings in a bottom section of the baffle than through a top section of the baffle for low catalyst flux stripping operations. When low catalyst flux is used, the catalyst runs from baffle to baffle closer to the bottom edge of the baffle. Hence, more fluidization from stripping medium is concentrated near the lower edge of the baffle. The greater fluidization at the bottom section of the baffle is accomplished by providing greater opening area per baffle area in the lower section of the baffle than in the top section of the baffle.

Abstract: Fluidized catalytic cracking process which process comprises: (a) separating the hydrocarbon product from the spent catalyst by means of one or more gas-solid separation steps; (b) stripping the spent catalyst in a dense phase fluidized stripping zone by introducing a stripping medium in the lower portion of the stripping zone; (c) introducing part of the spent catalyst obtained in step (b) to a regeneration zone wherein the coke is removed from the catalyst by means of combustion; (d) introducing the remaining part of the spent catalyst and part of the hot regenerated catalyst into a lower portion of an elongated dilute phase stripping zone; (e) introducing a stream of a stripping medium into the lower portion of the dilute phase stripping zone to contact the resulting mixture of spent catalyst and regenerated catalyst therein; (f) passing a stream of the spent catalyst mixed with the hot regenerated catalyst and stripping medium in the dilute phase stripping zone; (g) introducing the separated catalyst of s

Abstract: A catalyst regenerator for regenerating spent light FCC catalyst and heating the catalyst to supply heat to an FCC reactor. The regenerator has discharge outlets for catalyst and off gas and a valve for introducing spent catalyst through a central stand pipe portion. The regenerator houses a dense phase catalyst bed. A centerwell receives a lower end of the standpipe portion and defines an annulus therebetween. The spent catalyst is introduced through the standpipe portion into the annulus. A fuel distributor introduces fuel into the centerwell for mixing with the catalyst in the annulus. A fluidization distributor introduces fluidization gas into the centerwell for fluidizing the catalyst in the annulus. A radial slot in the centerwell introduces the catalyst and fuel mixture from the annulus below the upper surface of the dense phase bed. An air distributor located below the radial slot introduces combustion air into the dense phase bed.

Abstract: The present invention provides a catalytic cracking reactor system and process in which a riser reactor is configured to have two sections of different radii in order to produced improved selectivity to propene and butenes as products.

Abstract: This invention provides a method for controlling solids circulation in a gas-solids reaction system. The method entails aerating solid particles in a standpipe. Aeration fluid is injected into the standpipe at the appropriate location to increase apparent density of the solid particles.

Abstract: This invention relates to a process for catalytically upgrading light petroleum hydrocarbons accompanied by low temperature regenerating the catalyst, which comprises injecting the light petroleum hydrocarbons into a catalytic cracking reactor, contacting the light petroleum hydrocarbons with a regenerated catalyst and carrying out the reaction, separating the reaction products regenerating the stripped catalyst for 10 to 50 minutes under the regeneration conditions of a temperature of 400 to 600° C. and a pressure of 0.1 to 0.6Mpa; recycling the regenerated catalyst into the reactor. The process of the present invention can reduce the olefin content of gasoline, increase the cetane number of diesel oils, and decrease the contents of sulfur and nitrogen to some extent.

Abstract: A composition for controlling NOx emissions during FCC processes comprises (i) an acidic oxide support, (ii) cerium oxide, (iii) a lanthanide oxide other than ceria such as praseodymium oxide, and (iv), optionally, an oxide of a metal from Groups Ib and IIb such as copper, silver and zinc.

Abstract: An apparatus comprising a trickle valve positioned at the lower end of a vertical dipleg of a gas-solids separator comprising a pair of co-operable clamshell doors arranged in such a manner that mutual opposite swinging movement between a closed position wherein the doors adjoin along a midline, and an open position wherein the doors swing outwardly around a horizontal axis of rotation, is possible, and wherein either clamshell door is provided with means to press the doors together towards a closed position and at least one clamshell door is provided with an opening.

Abstract: A fluidized particulate solids contacting process for reducing regenerator flue gas NOx emissions and/or permitting operating with an increased equilibrium solids vanadium level, which process may be an FCC process or a fluidized particulate solid hydrocarbon treating process, wherein spent FCC catalyst or other spent solid is in a regenerator with an oxygen-containing regeneration gas under catalyst (solid) regeneration conditions which include a combination of at least a regeneration temperature and an oxygen level in the regeneration gas which is effective to burn off the spent solid a majority of carbonaceous deposits thereon, while substantially preventing the formation of NOx, and thereby produce a regenerated solid having a carbon level reduced from that of the spent solid and a flue gas; maintaining the regenerated solid in a fluidized state with a fluidizing media that substantially prevents any further oxidation or regeneration; and returning the fluidized regenerated solid to the reactor (contactor

Abstract: The operation of fluid catalytic converter (FCC) units can be stabilized through use of tests wherein a first catalyst and a second catalyst are introduced into the FCC unit in at least two different ratios, at two different times, in order to establish the effect of these catalyst ratios on a given operating parameter. This information is used to establish a unit response curve (or unit response envelope) for the catalyst ratios versus the operating parameter. This unit response curve (or envelope) is thereafter used to control the operation of the FCC unit.

Abstract: The production of carbon monoxide as a combustion off-gas is maximized by the use of a hot stripping zone arrangement that provides catalyst mixing to establish a uniform catalyst temperature and thorough contacting of the well-mixed hot catalyst in a confined portion of the hot stripping zone. The hot stripping zone delivers the hot stripped catalyst to a bubbling-bed regeneration zone by an oxygen-starved lift stream that distributes the catalyst to the top of the bubbling-bed in the regeneration zone. The process delivers spent catalyst with about 1 wt % of coke to the reaction zone and a spent combustion gas or flue gas stream having a CO.sub.2 to CO ratio of at least 1. The operation reduces the heat evolution in the regeneration step and allows relatively low temperature operation of the regeneration zone without use of catalyst coolers.