Abstract: An air distribution nozzle and fluidized bed including said nozzle, the nozzle including a gas inlet pipe and an air distribution cap defining a space inbetween them, first air outlet means allowing air to flow from the gas inlet pipe to the space and second outlet means allowing air to flow from said space to the ambient area, wherein said second outlet means has an outer cross section along the outer surface of the cap that varies in its vertical height along its horizontal extension.

Abstract: A fluidized fuel gas combustor system for a catalytic dehydrogenation process comprising a vessel having a lower portion and an upper portion; a plurality of air injection diffusers located in the lower portion of the vessel; a plurality of fuel gas injection diffusers located on fuel gas distributors disposed in the vessel and spaced apart from and above a plurality of air injection diffusers, wherein the fuel gas diffusers are placed in a manner to maximize even mass distribution of a fuel gas injected through the fuel gas diffusers in the vessel, wherein each fuel distributor comprises a tube having a plurality of fuel gas injection diffusers; and one or more grid assemblies disposed in the vessel spaced above the fuel gas distributors is provided.

Abstract: Processes are provided for producing a diesel fuel product having a sulfur content of 15 wppm or less (e.g., 10 wppm or less) from feed sources that include a biocomponent feedstock. The biocomponent feedstock can be initially co-processed with a mineral feed in a fluidized bed stage, such as an ebullating bed processing stage. Ebullating bed processing can mitigate the impact of the biocomponent feed on other hydrotreatment aspects of a diesel boiling range feed. Challenged biocomponent feeds can be handled by introducing the biocomponent feed into the ebullating bed reactor in a manner that reduces the fouling impact of the feed.

Abstract: This invention describes a two-stage regeneration zone that has a regenerated catalyst circuit such as the one that results from the mixing of a partially regenerated catalyst with a residual coke rate of between 0.3 and 0.7% and a totally regenerated catalyst with a coke rate that is less than 0.15%. All things being equal, this double-population regenerated catalyst enables the maximization of the LCO yield.

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: 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: A system for gas-solid separation and for stripping combined into a single so-called separation/stripping zone that is compact and thus contributes to the quality of the yields of the unit. This system can be applied to FCC units and makes it possible to obtain very good separation effectiveness while reducing the contact time between the gas and the solid at the same time.

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 process is disclosed for discharging and transferring upwardly fluidized particles from a dense fluidizing layer forming section to a high-velocity transferring section having a diameter which is smaller than that of the dense fluidizing fluidized layer forming section, wherein at least one intermediate cylindrical section is provided between the dense fluidizing fluidized layer forming section and the high-velocity transferring section. The process can decrease the degree of changes in the amount of particles to be discharged from the dense fluidizing layer forming section and transferred by the riser, thereby proving a stable and uniform transfer of the fluidized particles.

Abstract: Device that is integrated in a chamber that allows a separation of a mixture that comprises at least one gaseous fraction and one liquid fraction, whereby said mixture is obtained from a zone for bringing into contact a liquid phase, a gaseous phase and solid particles.

Abstract: A slurry phase reactor is designed to treat extra heavy petroleum crude in a combination of thermal-zone and catalytic-zone in a counterflow system where liquid feed is added to the top and hydrogen at the bottom. Feed enters the gas-phase thermal zone, where it passes to a liquid-phase thermal zone. In the liquid-phase thermal zone, the hydrocarbon is thermally cracked and the unreacted liquid is further passed to a catalytic-zone below in communication with the thermal-zone. Catalyst can be added or removed as required in a continuous mode without shutting down the system. The heat generated inside the catalytic cracking zone is distributed to the entire reactor as the gaseous product flows upward. Feed is brought to the reaction conditions by the heat recovered from the gas-phase zone. Reaction temperature could be controlled by feed temperature.

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: The sulfur content of liquid cracking products, especially the cracked gasoline, of the catalytic cracking process is reduced by the use of a sulfur reduction additive comprising a non-molecular sieve support containing a high content of vanadium. Preferably, the support is alumina. The sulfur reduction catalyst is used in the form of a separate particle additive in combination with the active catalytic cracking catalyst (normally a faujasite such as zeolite Y) to process hydrocarbon feedstocks in the fluid catalytic cracking (FCC) unit to produce low-sulfur gasoline and other liquid products.

Abstract: The upstream portion of a reactor (1), contains, between the feeding area of the catalyst flow and the injection area of the charge to be cracked, at least one solid and attached packing element (6, 6′), that extends over all or part of the cross section of the reactor and consists of a network of cells through which pass the catalyst particles. This network makes it possible to create at least one step of division and recombination of the flow of catalyst particles, so as to redistribute the latter in a homogenous manner over the cross section of the reactor.

Abstract: Compositions comprising a component containing (i) an acidic oxide support, (ii) an alkali metal and/or alkaline earth metal or mixtures thereof, (iii) a transition metal oxide having oxygen storage capability, and (iv) palladium promote CO combustion in FCC processes while minimizing the formation of NOx. The acidic oxide support preferably contains silica alumina. Ceria is the preferred oxygen storage oxide.

Abstract: A two-stage process for converting petroleum residua and other low value oils to high valued gasoline blendstocks and light olefins. The first stage is comprised of a thermal process unit containing a reaction zone comprised of a horizontal moving bed of fluidized hot particles operated at temperatures from about 500 to 600° C. and having a short vapor residence time, and the second stage is comprised of a catalytic conversion zone operated at a temperature of about 525° C. to about 650° C., and also having a short vapor residence time, preferably shorter than that of the first stage reaction zone.

Abstract: A method, and a reactor, for hydroprocessing a hydrocarbon feed stream through multistage moving catalyst beds contained within a single onstream reactor vessel, with separate catalyst addition and withdrawal systems for each of the multistages of moving catalyst beds. The reactor contains two or more different and distinct moving catalyst beds for any hydroprocessing application. The method includes serially passing, without leaving the reactor vessel, at least a partially treated hydrocarbon stream from one hydroconversion reaction zone containing a moving catalyst bed with a first set of catalytic characteristics to another hydroconversion reaction zone containing a moving catalyst bed with a second set of catalytic characteristics that differ in catalytic abilities from the first set of catalytic characteristics.

Abstract: A cavitation enhanced atomizing process comprises forming a flowing solution of the liquid to be atomized and a lower boiling cavitating liquid. This flowing solution is then contacted with a pressure reducing means, at a temperature below the bubble point of the cavitating liquid in the solution, to produce cavitation bubbles. These bubbles comprise cavitation liquid vapor and the bubble nucleation produces a two-phase fluid of the bubbles and liquid solution. The two-phase fluid is passed downstream into and through an atomizing means, such as an orifice, and into a lower pressure atomizing zone, in which the bubbles vaporize to form a spray of liquid droplets. The nucleated bubbles also grow in size as the so-formed two-phase fluid passes downstream to and through the atomizing means.

Abstract: A process for the fluid catalytic cracking of heavy feeds under a heat balance regime is described, where one or more catalyst coolers external to the regenerator cool a stream of regenerated catalyst. A portion of said stream returns to the regenerator and a portion of the cooled regenerated catalyst is admixed to the non-cooled regenerated catalyst at a temperature substantially lower than the regenerator temperature, said admixture being brought into contact with the hydrocarbon feed to be cracked. As a result, the control of the catalyst circulation is rendered independent from the heat balance of the unit, with minimization of the thermal cracking, and therefore lower coke and fuel gas products.

Abstract: An FCC feed injection arrangement injects feed transversely from the sides of a restricted opening into a stream of FCC catalyst to provide good feed and catalyst contacting in an arrangement that simplifies external pipe configurations and maintenance of the feed injection system. The invention forms a venturi or restricted opening by forming a generally square opening between two parallel extended chords on opposite sides of the riser. A venturi area may be built out of refractory lining or other abrasion resistant structures. The invention may use horizontally extended pipes that are tangentially positioned apart from each other across from the restricted opening to provide a simple construction for the feed injection arrangement. The pipes are easily inserted and withdrawn from the riser to permit easy maintenance of the nozzles in the highly erosive environment.

Abstract: An arrangement for the controlled production of an essentially linear array of hydrocarbon feed injection jets reduces required clearances and elevation while facilitating modification of the contacting locating a feed distributor containing a linear array of jets at a standpipe junction point to provide choke point for particle flow control. The flow properties of the extended particle layer are controlled by adjusting the density of the particles above the choke point created by the upper part of the standpipe inside diameter and the top of the distributor. Steam or another fluidization medium may be added to the particles directly above the distributor for this purpose. This invention can also modify the particle or feed injection characteristics by changing the projection of the distributor into the standpipe to adjust the flow area over the choke point and by the use of bottom slides or baffles to change the flow area size and configuration.

Abstract: An improved stripper section design is provided for use in fluid catalytic cracking (FCC) units. The stripper section contains means for imparting rotational movement to the FCC cracking catalyst as it traverses the stripping section. In one embodiment the stripper section contains at least one rotation vane that is preferably disposed on the surface of a stripper section tray. The rotation vane provides angular, rotational movement to the cracking catalyst as it traverses the stripper section. Vertical movement is imparted to the cracking catalyst due to gravity and radial movement is imparted to the catalyst due to the slanted nature of the tray. Through the use of the rotation vanes the contact between the catalyst particles and the stripping steam is increased, thereby improving the overall efficiency of the FCC operation.

Abstract: A two-stage process for obtaining a substantial amount of olefinic product from a residua feedstock. The first stage is comprised of a thermal process unit containing a reaction zone comprised of a horizontal moving bed of fluidized hot particles operated at temperatures from about 500.degree. to 600.degree. C. and having a short vapor residence time, and the second stage thermal conversion zone operated at a temperature of about 700.degree. C. to about 1100.degree. C., and also having a short vapor residence time.

Abstract: A two-stage process for obtaining a substantial amount of olefinic product from a residua feedstock. The first stage is comprised of a thermal process unit containing a reaction zone comprised of a horizontal moving bed of fluidized hot particles operated at temperatures from about 500.degree. to 600.degree. C. and having a short vapor residence time, and the second stage thermal conversion zone operated at a temperature of about 700.degree. C. to about 1100.degree. C., and also having a short vapor residence time.

Abstract: This invention makes possible substantially continuous flow of uniformly distributed hydrogen and hydrocarbon liquid across a densely packed catalyst bed to fill substantially the entire volume of a reactor vessel by introducing the fluids as alternate annular rings of gas and liquid (i.e. a mixture of liquid hydrocarbon and a hydrogen-containing gas) at a rate insufficient to levitate or ebullate the catalyst bed. Catalyst are selected by density, shape and size at a design feed rate of liquids and gas to prevent ebullation of the packed bed at the design feed rates. Catalysts are selected by measuring bed expansion, such as in a large pilot plant run, with hydrocarbon, hydrogen, and catalyst at the design pressures and flow velocities. The liquid and gas components of the feed flow into the bed in alternate annular rings across the full area of the bed.

Abstract: A process for deasphalting a residua feedstock by use of a short vapor contact time thermal process unit comprised of a horizontal moving bed of fluidized hot particles. It is preferred that a mechanical means be used to fluidize a bed of hot particles.

Abstract: The subject invention describes a synthetic crystalline aluminosilicate of the pentasil type and method for using the same as a catalyst or a catalyst component in petrochemical processes for the catalytic conversion of hydrocarbons and their derivatives into useful organic compounds and intermediates.

Abstract: An FCC feed distributor mixes fresh catalyst entering the riser with steam to create a dense bubbling bed of catalyst. Fluidized catalyst rises from the dense bed around a conical section supported from the bottom of the riser. The conical section accelerates the catalyst by reducing the flow area into a small width annulus. As fast fluidized catalyst flows to the annulus, a diverter outwardly redirects an axially flowing feed stream to discharge feed radially into the catalyst as it flows by the annular section. A narrow width of the annular section provides good penetration of the catalyst stream by the feed to quickly and completely mix the catalyst and feed. A tapered conical section above the narrow annular section provides an extended region of gradually increasing flow area that controls downstream acceleration of the gas and catalyst mixture by permitting expansion and preventing back mixing over the initial stages of the cracking reaction.

Abstract: A fluidized-bed process for catalytic cracking of a hydrocarbon feedstock where the hydrocarbon feedstock, particularly a feedstock with a high content of basic nitrogen compounds, and a catalyst circulate in the tubular zone co-currently from the top to the bottom, where the catalyst, which is under equilibrium conditions at 150.degree. C., and a pressure of 5 mbar, adsorbs less than 250 micromols, and preferably less than 50 micromols, of pyridine/g, and whose pyridine retention, after heating at 350.degree. C. under vacuum, does not exceed 20%, and preferably not 10%, of the amount adsorbed at 150.degree. C.

Abstract: This FCC process suspends a layer of catalyst in a riser proximate or above the riser outlets. The density at the riser outlets is higher than the flowing density in the riser. The suspended catalyst provides a disengagement zone that enhances the separation of catalyst from product vapors. The riser operates in a manner that prevents any discharge of catalyst from its end. The arrangement also provides a convenient method for vetoing stripping vapors into a closed reactor cyclone system.

Abstract: This invention makes possible substantially continuous flow of uniformly distributed hydrogen and hydrocarbon liquid across a densely packed catalyst bed to fill substantially the entire volume of a reactor vessel by introducing the fluids as alternate annular rings of gas and liquid (i.e. a mixture of liquid hydrocarbon and a hydrogen-containing gas) at a rate insufficient to levitate or ebullate the catalyst bed. Catalyst are selected by density, shape and size at a design feed rate of liquids and gas to prevent ebullation of the packed bed at the design feed rates. Catalysts are selected by measuring bed expansion, such as in a large pilot plant run, with hydrocarbon, hydrogen, and catalyst at the design pressures and flow velocities. The liquid and gas components of the feed flow into the bed in alternate annular rings across the full area of the bed.

Abstract: An FCC feed distributor mixes fresh catalyst entering the riser with steam to cream a dense bubbling bed of catalyst. Fluidized catalyst rises from the dense bed around a conical section supported from the bottom of the riser. The conical section accelerates the catalyst by reducing the flow area into a small width annulus. As fast fluidized catalyst flows to the annulus, a diverter outwardly redirects an axially flowing feed stream to discharge feed radially into the catalyst as it flows by the annular section. A narrow width of the annular section provides good penetration of the catalyst stream by the feed to quickly and completely mix the catalyst and feed. A tapered conical section above the narrow annular section provides an extended region of gradually increasing flow area that controls downstream acceleration of the gas and catalyst mixture by permitting expansion and preventing back mixing over the initial stages of the cracking reaction.

Abstract: Disclosed is a method for fluidizing a dense phase bed of solid particles, preferably a method for fluidizing a dense phase bed of solid catalyst particles. The method includes the steps of continuously supplying a flowing fluid stream in a downward direction within an enclosed volume; contacting an upper surface of a dense phase bed of solid particles resting within the enclosed volume with the downward flowing fluid stream; continuously directing the flowing fluid stream into the dense phase bed of particles to form a continuous fluidized bed of solid particles within the enclosed volume; directing the flowing fluid stream in an upward direction after contacting the upper surface of the dense phase bed; and collecting the flowing fluid stream.

Abstract: This invention makes possible substantially continuous flow of uniformly distributed hydrogen and hydrocarbon liquid across a densely packed catalyst bed to fill substantially the entire volume of a reactor vessel by introducing the fluids as alternate annular rings of gas and liquid (i.e. a mixture of liquid hydrocarbon and a hydrogen-containing gas) at a rate insufficient to levitate or ebullate the catalyst bed. Catalyst are selected by density, shape and size at a design feed rate of liquids and gas to prevent ebullation of the packed bed at the design feed rates. Catalysts are selected by measuring bed expansion, such as in a large pilot plant run, with hydrocarbon, hydrogen, and catalyst at the design pressures and flow velocities. The liquid and gas components of the feed flow into the bed in alternate annular rings across the full area of the bed.

Abstract: An FCC process uses a highly efficient separation device to remove product from the catalyst so that the reactor vessel receives a low volume of feed hydrocarbons and riser by-products. The separation device encloses an upwardly directed outlet end of a ballistic separation device in low volume disengaging vessel that collects disengaged catalyst from the riser in a dense bed. Immediate contact of the dense bed with a stripping fluid minimizes the amount of hydrocarbons that are carried out of the disengaging vessel into the open volume of the reactor vessel.

Abstract: A process is described for ultrapyrolytic upgrading of a heavy hydrocarbon oil feedstock by contacting the feedstock in a confined riser vertical column with finely divided inert solid particles under ultrapyrolysis conditions, the riser forms part of an internally circulating aerated bed reactor with the bottom end of the riser being directly connected to an inlet nozzle feeding the heavy hydrocarbon oil feedstock and the upper end of the riser extending above an annular aerated bed of the finely divided solid particles surrounding the riser. The riser also includes a plurality of orifices in a lower region thereof flow connected to a lower region of the aerated bed for controlled delivery of the particles from the aerated bed into the riser.

Abstract: An FCC feed distributor mixes fresh catalyst entering the riser with steam to create a dense bubbling bed of catalyst. Fluidized catalyst rises from the dense bed around a conical section supported from the bottom of the riser. The conical section accelerates the catalyst by reducing the flow area into a small width annulus. As fast fluidized catalyst flows to the annulus, a ring of small diameter nozzles shoot feed across the narrow annular gap into the moving catalyst. The narrow gap provides good penetration of the catalyst stream to completely mix the catalyst and feed. A gently tapered conical section above the annular gap provides an extended region of gradually increasing flow area that controls downstream acceleration of the gas and catalyst mixture by permitting expansion and preventing back mixing over the initial stages of the cracking reaction.

Abstract: An FCC process decouples the circulation of catalyst on the regeneration side of the process from the circulation of catalyst on the reactor side of the FCC process by mixing the spent and regenerated catalyst from the reactor and regenerator side of the process in a common blending vessel that receives all of the spent and regenerated catalyst from the reactor and regenerator. The blending vessel supplies blended catalyst to raise the solids to oil ratio on the reaction side of the process and regulate catalyst temperatures on the reaction and the regeneration sides of the process. The blending vessel can also retain the majority of the catalyst inventory for both the reactor and regenerator sides of the process. Moreover, by the introduction of a stripping gas into the blending vessel it operates as a hot stripper to remove additional hydrocarbons from the blended catalyst that enters the regeneration zone.

Abstract: A process and apparatus for increasing the coke burning capacity of FCC catalyst regenerators is disclosed. An auxiliary regenerator receives spent catalyst from an FCC stripper and burns some of the coke at turbulent or fast fluidized bed conditions. Partially regenerated catalyst and flue gas enter a low pressure drop cyclone discharging more than 90% of the partially regenerated catalyst down into a bubbling or fast fluidized bed in the primary regenerator. Flue gas from the auxiliary regenerator is discharged into the dilute phase above the bed in the primary regenerator. Catalyst entrainment from the fluidized bed in the primary regenerator may be reduced because less combustion air is needed as a result of partial regeneration in the auxiliary regenerator. Reduced NOx and dust emissions, and/or increased coke burning capacity, may be achieved, especially when a bubbling dense bed primary catalyst regenerator is used.

Abstract: A catalytic cracking unit is disclosed which provides for separation and quenching of a catalytic cracking effluent.

Abstract: FCC process uses an open reactor vessel to house cyclones or other separation devices that reduce the carry through of product gases with the catalyst into the reactor vessel to less than 10 wt. % so that the catalyst in the reactor vessel provides a secondary dealkylation zone. By using a highly efficient separation device to remove product from the catalyst, the environment in the reactor vessel receives a low volume of cracked hydrocarbons from the riser conversion zone and provides a convenient secondary reaction zone that receives a recycled heavy gasoline fraction separated from the riser product stream. Dealkylation in the secondary reaction zone provides additional light gasoline to satisfy T90 requirements.

Abstract: In ebullated bed hydroprocessing of a distillate hydrocarbon feedstock, it has been found that high pressure and low pressure heat exchange can be separated. Both the high pressure heat exchange and the fired heater fuel consumption are reduced. A control system provides for a constant distillate feedstock temperature in cooperation with heat integration.

Abstract: A process for short contact time cracking of heavy feed. A falling, annular curtain of hot regenerated FCC catalyst, or hot inert solids, is formed over a cone shaped plug valve. Hydrocarbons pass from under the cone, or via a hollow stem, in radial in to out flow to contact the falling curtain of solids. After 0.01 to 1.0 seconds of contact time, solids and cracked vapor are separated, preferably in a bell separator beneath the reaction zone. Downflow of reactants into a contiguous upflowing stripper minimizes attrition.

Abstract: This FCC process suspends a catalyst and a riser proximate or above the riser cyclone inlets at a density that is higher than the flowing density in the riser. The suspended catalyst provides a disengagement zone that enhances the separation of catalyst from product vapors. The riser operates in a manner that prevents any discharge of catalyst from its end. The arrangement also provides a convenient method for venting stripping vapors into a closed reactor cyclone system.

Abstract: This invention provides a method of reducing the sulfur oxide emissions from the regenerator of an FCC process that cracks a sulfur containing feedstream. The sulfur oxide emissions are reduced by using an essentially sulfur free lift gas stream to shift the sulfur concentration equilibrium between the product stream from the reaction zone and the flue gas stream from the regeneration zone. Sulfur compounds present in the FCC feed leave the reaction zone as volatile sulfurous gases in the product vapor stream or as adsorbed sulfur compounds on the catalyst. Sulfurous gas in the product vapors is mainly H.sub.2 S. By lowering the concentration of H.sub.2 S that enters the riser with the lift gas the equilibrium reaction of sulfur with hydrogen in the riser is favorably shifted to increase the production of H.sub.2 S and decrease the lay down of sulfur compounds in the coke that forms on the catalyst.

Abstract: Coke formation/deposition within and downstream of catalytic cracking reactors is suppressed by adding a coke suppressing additive to the cracking reactor and/or cracked product vapor. Free radical inhibitors, such as oxygenates, are preferred. The additive addition rate is preferably controlled based on temperature of regenerated catalyst, or a direct or indirect measurement of coke accumulation on the transfer line between the cracking reactor and the main fractionator.

Abstract: In an ebullated bed process, a nominal 1000.degree. F.+ boiling point vacuum residuum is hydrotreated at a first temperature of 750.degree. F. to 875.degree. F. and total pressure of 1900 psig to 3000 psig. Hydrogen partial pressure is controlled by changing total reactor pressure in the range of 1700 psig to 2300 psig to achieve a selected yield of 650.degree. F.- boiling material.

Abstract: A process and apparatus for multi-stage fluidized bed regeneration of spent FCC catalyst in a single vessel. At least two isolated relatively dense phase fluidized beds are disposed beneath a common dilute phase region. Spent catalyst discharged into a primary regeneration stage is regenerated to produce flue gas and partially regenerated catalyst, which preferably overflows into the second stage. Flue gas and entrained catalyst from each fluidized bed are processed in two trains of separation means, preferably cyclones. The inlets of each train are disposed above the isolated fluidized beds, and are effectively separated although sharing an open dilute phase region.

Abstract: An FCC process uses an open reactor vessel to house cyclones or other separation devices that reduce the carry though of product gases with the catalyst into the reactor vessel to less than 5 wt. % so that the catalyst in the reactor vessel can contact a secondary feedstock. By using a highly efficient separation device to remove product from the catalyst the environment in the reactor vessel receives a low volume of feed hydrocarbons and riser by-products. These by products comprise mainly C.sub.2 and lighter gases which are inert to a variety of other feedstreams. Possible secondary feedstreams include hydrotreated heavy naphtha, hydrotreated light cycle oil, light reformate and olefins. It is highly useful to use the secondary feedstream to heat the catalyst in the reactor vessel to facilitate hot stripping of the catalyst. Heat may be introduced in this manner by heating the secondary feedstream or using a feedstream that produces an exothermic reaction in the reactor vessel.