Abstract: A tube heat exchange reactor for carrying out an endothermic catalytic reaction. The tube heat exchange reactor includes: an outer tube with a first and a second end, where the first end is an inlet end and where the second end is a closed end, an inner tube coaxially arranged within the outer tube and spaced apart from the outer tube, where at least a part of the inner tube holds a bed of catalyst material susceptible for induction heating and where the inner tube has an inlet end and an outlet end, an induction coil placed within the annular space confined between the outer and the inner tube, and a power source arranged to supply alternating current to the induction coil in order to generate an alternating magnetic field within at least a part of the inner tube.

Abstract: The present invention describes a type of inclined bed reactor which permits a small quantity of catalyst to be employed. Application of the reactor to a regenerative reforming process.

Abstract: Disclosed herein is a catalyst dumping spool assembly for unloading used catalyst from an inside of a reactor, comprising: a reactor, and a catalyst dumping spool comprising a first end operatively connected to the reactor, the first end having a catalyst inlet through which the used catalyst is introduced into, a second end having a catalyst discharge outlet whereby the used catalyst exits the catalyst dumping spool, wherein a first device for controlling used catalyst transfer into the catalyst inlet is positioned proximate the first end, and a second device for controlling the used catalyst transfer from inside the catalyst inlet through the catalyst discharge outlet is positioned proximate the second end, and further wherein the catalyst dumping spool further comprise a gas fluidization inlet and a water fluidization inlet located between the first and second devices.

Abstract: Apparatuses and methods are disclosed for contacting radially flowing fluids with solid particles (e.g., catalyst) with reduced tendency for fluidization of the particles, and especially a sealing portion of the particles at the top of a particle retention zone disposed between screens at upstream and downstream positions relative to radial fluid flow. Fluidization is reduced or eliminated by offsetting openings of the screens in the axial direction, such that upstream openings in the upstream screen are above highest downstream openings in a downstream stream. The offset in openings imparts a downward flow component to radially flowing fluid, thereby reducing solid particle fluidization without the need to induce a specific pressure drop profile along the entire axial direction of the screens.

Abstract: An apparatus for contacting a bed of particulate material with a cross flowing fluid, which maintains the bed of particulate material within a retention volume. The apparatus includes partitions for retaining particles, with apertures disposed within the partitions. The apertures are covered by louvers that extend above the edges of the apertures to prevent solid particles from spilling through inlet apertures.

Abstract: A method of separating a mixture of liquid and insoluble solids in a filter press may comprise: pumping the mixture into a chamber between two filter plates in the filter press to form a filter cake, wherein the chamber is lined by filter cloths, and wherein, during the pumping, filtrate is forced through the filter cloths and out of the chamber; heating the filter cake in the chamber, wherein, during the heating, filtrate is forced through the filter cloths and out of the chamber, and wherein the heating is by radio frequency irradiation of the filter cake in the chamber; and releasing dried filter cake from the chamber.

Abstract: One exemplary embodiment can include a hydrocarbon conversion process. Generally, the process includes passing a hydrocarbon stream through a hydrocarbon conversion zone comprising a series of reaction zones. Typically, the hydrocarbon conversion zone includes a staggered-bypass reaction system having a first, second, third, and fourth reaction zones, which are staggered-bypass reaction zones, and a fifth reaction zone, which can be a non-staggered-bypass reaction zone, subsequent to the staggered-bypass reaction system.

Abstract: One exemplary embodiment can include a hydrocarbon conversion process. Generally, the process includes passing a hydrocarbon stream through a hydrocarbon conversion zone comprising a series of reaction zones. Typically, the hydrocarbon conversion zone includes a staggered-bypass reaction system having a first, second, third, and fourth reaction zones, which are staggered-bypass reaction zones, and a fifth reaction zone, which can be a non-staggered-bypass reaction zone, subsequent to the staggered-bypass reaction system.

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 horizontal chemical reactor comprises at least one catalytic bed (5a-5d) arranged horizontally in the reactor and comprising a lower gas-permeable wall (6) for gas outlet, and a holding element (2) of the at least one catalytic bed.

Abstract: A process for contacting a bed of particulate material, usually catalyst, with a transverse flow of fluid is disclosed. The particulate material moves or is prevented from not moving, while the fluid passes through the bed at a rate greater than the stagnant bed pinning flow rate. This invention is applicable to hydrocarbon conversion processes and allows for higher fluid throughput rates compared to prior art processes.

Abstract: An apparatus for mixing a fluid feed stock, such as a heavy oil, and particles of a catalyst for gasifying the heavy oil in a reactor, comprises the reactor having in the upper portion a circular port through which the particles are fed, a moving bed-forming section disposed on and in communication with the reactor for forming the particles into an annular or cylindrical high-velocity moving bed by dropping the particles downwardly into the reactor, while dispersing the particles radially, an external fluid feed section located so as to spray the feed stock over the entire upper outer periphery of the annular or cylindrical moving bed passing through the reactor, and an internal fluid-feed section located so as to spray the fluid over the entire upper inner periphery corresponding to the outer periphery of the annular moving bed.

Abstract: An apparatus for mixing a fluid feed stock, such as a heavy oil, and particles of a catalyst for gasifying the heavy oil in a reactor, comprises the reactor having in the upper portion a circular port through which the particles are fed, a moving bed-forming section disposed on and in communication with the reactor for forming the particles into an annular or cylindrical high-velocity moving bed by dropping the particles downwardly into the reactor, while dispersing the particles radially, an external fluid feed section located so as to spray the feed stock over the entire upper outer periphery of the annular or cylindrical moving bed passing through the reactor, and an internal fluid-feed section located so as to spray the fluid over the entire upper inner periphery corresponding to the outer periphery of the annular moving bed.

Abstract: An arrangement for the controlled production of an essentially linear array of hydrocarbon feed injection jets maintains stable and reliable jets by passing individual piping for each jet through a support shroud that is located in a contacting vessel. Controlled atomization is provided by independently injecting a uniform quantity of gas medium into each of the plurality of uniformly created feed injection streams upstream of a discharge nozzle that separately discharges each mixed stream of hydrocarbons and gas medium into a stream of catalyst particles at or about the inner end of the support shroud. The feed injection jets are suitable for positioning in an inner location of large contacting vessel. Uniformity of distribution is obtained by dividing the hydrocarbons streams from an oil header into an individual oil conduit for each spray injection nozzle.

Abstract: A process for contacting reactants with a particulate catalyst while indirectly contacting the reactants with a heat exchange medium amid simultaneous exchange of catalyst particles by an operation that sequentially restricts reactant flow while moving catalyst through reaction stacks in which the reactant flow has been restricted. The process permits a change out of catalyst in a channel type reactor arrangement that would normally restrict catalyst flow during operation. Moving catalyst through a heat exchange type reactor having reactant and heat exchange channels permits control of catalyst activity as well as temperatures.

Abstract: A method for replacing particles in a process that transfers particles is disclosed. This invention employs a seal zone which is in communication with two zones of the process and in which particles that are being added to the process are purged. This invention allows particles to be replaced without reducing the normal rate of particle transfer through the process, which results in a savings in downtime costs. This invention is adaptable to a multitude of processes for the catalytic conversion of hydrocarbons in which deactivated catalyst particles are regenerated.

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: This invention makes possible substantially continuous flow of uniformly distributed hydrogen and hydrocarbon liquid across a densely packed catalyst bed which substantially fills the entire volume of a reactor vessel. Catalyst are selected to be essentially the same density, shape and size at a design feed rate of liquids and gas to prevent ebullation of the packed catalyst bed at the design feed rates. The liquid and gas components of the hydrocarbon feed stream flow into the bed of catalyst and a quenching medium, which is preferably a liquid, is injected into the bed of catalyst. Injection of a liquid quench reduces the gas component of the hydrocarbon feed stream while simultaneously increasing the residence time and reducing the liquid velocity of the liquid component of the hydrocarbon feed stream within the substantially packed bed of catalyst.

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 method and apparatus for replacing particles in a process that transfers particles is disclosed. This invention employs a seal zone which is in communication with two zones of the process and in which particles that are being added to the process are purged. This invention allows particles to be replaced without reducing the normal rate of particle transfer through the process, which results in a savings in downtime costs. This invention is adaptable to a multitude of processes for the catalytic conversion of hydrocarbons in which deactivated catalyst particles are regenerated.

Abstract: This invention makes possible substantially continuous flow of uniformly distributed hydrogen and hydrocarbon liquid across a densely packed catalyst bed which substantially fills the entire volume of a reactor vessel. Catalyst are selected to be essentially the same density, shape and size at a design feed rate of liquids and gas to prevent ebullation of the packed catalyst bed at the design feed rates. The liquid and gas components of the hydrocarbon feed stream flow into the bed of catalyst and a quenching medium, which is preferably a liquid, is injected into the bed of catalyst. Injection of a liquid quench reduces the gas component of the hydrocarbon feed stream while simultaneously increasing the residence time and reducing the liquid velocity of the liquid component of the hydrocarbon feed stream within the substantially packed bed of catalyst.

Abstract: On-stream catalyst replacement hydroprocessing method wherein an upstream mixture of hydrogen and hydrocarbon liquid counter flows through a downwardly moving bed of hydroprocessing catalyst in a reactor vessel. The mixed feed stream of hydrogen and liquid hydrocarbon components enters a surge zone between the lower end of the reactor and a plenum zone to form a common pool under a conical support for the lower end of the downflowing catalyst bed. The mixed feed enters the plenum chamber through a plurality of passageways extending downwardly from the plenum zone to the same depth adjacent the lower end of the surge zone so that the liquid component normally prevents hydrogen from establishing independent paths before entering the plenum zone. Separation of the hydrogen and hydrocarbon liquid components from the mixed feed is thus assured to occur in the plenum zone directly below the pervious conical support to form a plurality of stepped concentric local reservoir rings under the conical support.

Abstract: Apparatus for regenerating spent hydrocarbon conversion catalyst. Catalyst particles in a vertically-elongated movable tapered bed are contacted with a hot oxygen-containing gas stream in order to remove, by means of combustion, coke which accumulated on the catalyst particles while they were used in a hydrocarbon conversion zone. Catalyst moves downward under the influence of gravity. The catalyst bed is tapered such that the thickness of the bed, in a dimension which is transverse to the direction of catalyst movement, varies from a minimum at the top of the tapered bed to a maximum at the bottom of the tapered bed. Gas passes through the tapered bed in a direction which is substantially transverse to the direction of catalyst movement. Substantially, all of the catalyst in the bed is in contact with the flowing gas.

Abstract: Method for effecting contact of a gas with light particles of solid matter, where the particles are retained within particle retention screens to form a bed of particles and the particles move downward in plug flow by means of gravity. When the particles are light, that is, of relatively small size and low density, the velocity of the gas may be sufficiently high that downward movement of particles is hindered by the horizontal forces exerted on the particles by the flowing gas. This invention provides that gas flows through the bed of particles in a downwardly sloping direction instead of in a horizontal direction, so that the force exerted on a particle has a horizontal component and a downward vertical component. The vertical component of the force resulting from gas flow, along with the gravity force on a particle, is sufficient to overcome the frictional resistance to downward movement of a particle which results from the horizontal component of the flowing gas force.

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 at a rate insufficient to levitate the bed and with catalyst selected by a density, shape and size at a design feed rate of liquids and gas to prevent ebulation of the packed bed at the design feed rates. Catalysts are selected by measuring bed expansion 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 improved method of controlling catalyst inventory in the reactor of an ebullated bed process has been discovered. Pressure differentials are measured to calculate a catalyst inventory characterization factor. Aged catalyst is withdrawn and fresh catalyst added in an amount to reestablish the value of the factor.The catalyst to oil ratio is maintained despite changes in bed ebullation, gas and liquid holdups and oil residence time changes.

Abstract: Method and apparatus for effecting treatment needed to regenerate spent hydrocarbon conversion catalyst. The invention may be termed a variable gas flow catalyst bed. Catalyst particles in a vertically-elongated movable bed are contacted with a hot oxygen-containing gas stream in order to remove, by means of combustion, coke which accumulated on the catalyst particles while they were used in a hydrocarbon conversion zone. The catalyst particles are confined in the bed by means of catalyst retention screens. The catalyst retention screens are configured such that gas flow through the bed varies from a maximum at the top of the bed to a minimum at the bottom of the bed. The variation in gas flow is accomplished by varying the size of gas flow apertures in the retention screens from a maximum at the top of the bed to a minimum at the bottom of the bed.

Abstract: A method for regenerating coke-contaminated catalyst particles achieves better utilization of oxygen and minimizes surface area loss of the catalyst by confining particles in the combustion section of a regeneration zone to a tapered bed configuration. In this method, catalyst particles move through the regeneration zone in continuous or semi-continuous flow and are formed into a vertically elongated bed of particles in the regeneration zone. An oxygen-containing gas is passed through the particle bed in a transverse direction and initiates combustion of the coke deposits along a burn front that extends diagonally through the catalyst bed from the inlet surface of the bed to the outlet surface of the bed.

Abstract: The invention concerns a process for withdrawing catalyst, particularly from a moving bed.The device is characterized in that fins (4) (see FIG. 1A), shaped as corner-plates, are arranged, on a plate (6) which supports the catalyst bed radially around each vertical duct for catalyst withdrawal, so that the flow of catalyst particles converges towards the withdrawing ducts.The apparatus is useful for example in hydroconversion reactions, particularly in hydrotreatments of heavy oil cuts.

Abstract: A system is disclosed for circulating an ancillary hydrogen-rich gas stream through a part of a moving bed hydrocarbon conversion process. The gas stream may be employed in lockhopper systems, catalyst transfer equipment and catalyst treating zones as for reducing the catalyst. The used ancillary gas is discharged into a partitioned vapor-liquid separation vessel. The partially condensed reaction zone effluent stream is discharged into a different chamber of the same vessel. The net off gas stream is withdrawn from the chamber receiving the used ancillary gas to prevent contamination of a recycle gas stream, which is drawn off the other chamber.

Abstract: The present invention relates to a continuous process for the catalytic treatment of a hydrocarbon oil and an apparatus for carrying out such process, by passing said oil through one or more catalyst beds within a reactor wherein catalyst is withdrawn from the bottom of the reactor and fresh catalyst is supplied to the top thereof, said catalyst being withdrawn through a discharge funnel contained in the bottom of said reactor, which funnel allows for separation of product from the catalyst via a first main screen located in the funnel upstream of the exit end of said funnel, the withdrawal of product being effected via a product outlet, in which process use is made of a second screen forming part of the discharge funnel system, located between the main screen of the funnel and the product outlet and having a larger mesh size.

Abstract: The present invention relates to a movable catalyst bed reactor provided with catalyst bed supporting and guiding means in the shape of one or more downwardly converging conical surfaces with one or more vertical outlet channels connected to the lower end(s) of the conical surface(s), the supporting and guiding means comprising one or more screen sections for withdrawal of reactor effluent from the catalyst, and separate outlet means for reactor effluent and catalyst, wherein the vessel is further provided with conduit means for forming a protecting layer of substantially spherical particles along the surface(s) of the screen section(s) facing catalyst, which layer is movable along the screen section(s).

Abstract: A method is disclosed for regenerating particulate catalyst used in a hydrocarbon conversion process such as catalytic reforming. The method is especially applicable to moving bed reactor systems. The catalyst being regenerated slowly moves downward as a dense bed which is contacted with different gas streams at different elevations within the regeneration zone. The invention involves employing a portion of relatively hot combustion gas as a heating gas stream, with the remainder of the combustion gas being cooled and recycled to the combustion zone. This eliminates the need to employ a heater to provide a suitable heating gas stream.

Abstract: An improved moving bed continuous catalytic cracking process for cracking hydrocarbon feedstocks, such as gas oil, in the absence of added hydrogen, which includes the use of a minute amount of dispersed platinum supported directly on a cracking catalyst. The trace of platinum induces a substantial increase in the heat efficiency with which coke on catalyst is converted to CO.sub.2 in the regenerator section with minimal or no detriment to the cracking reaction.

Abstract: A multiple stage hydrocarbon conversion system wherein a hydrogen-hydrocarbonaceous feedstock reaction mixture is processed serially through a plurality of reaction zones, each of which contains a particulate catalyst disposed as an annular-form bed movable downwardly through the reaction zone, and wherein said reaction mixture is processed in radial flow through said annular-form bed. Pinning of the catalyst particles within the annular-form bed is substantially obviated by the combined effect of charging only a portion of the total hydrogen to the first reaction zone, charging the balance of the total hydrogen to a subsequent reaction zone, and restricting the effluent flow of at least one reaction zone.

Abstract: A multiple stage hydrocarbon conversion system wherein a hydrogen-hydrocarbonaceous feedstock reaction mixture is processed serially through a plurality of reaction zones, each of which contains a particulate catalyst disposed as an annular-form bed movable downwardly through the reaction zone, and wherein said reaction mixture is processed in radial flow through said annular-form bed. Pinning of the catalyst particles within the annular-form bed is substantially alleviated by the device of charging only a portion of the total hydrogen to the first reaction zone, and charging the balance of the total hydrogen to a subsequent reaction zone.

Abstract: A catalytic reaction chamber for contacting a reactant stream with catalyst particles which are disposed as an annular-form bed and are downwardly movable therethrough via gravity-flow. The annular catalyst bed is spaced between a catalyst-retaining screen and a scalloped, perforated centerpipe. A plurality of vertically-positioned catalyst-transfer, or withdrawal, conduits are circumferentially-disposed substantially adjacent the outer surface of the scalloped centerpipe and extend the entire length of the catalyst bed. These contain a first plurality of apertures which face into the bed of catalyst particles and which are sized to permit catalyst particles to flow therethrough. A second plurality of apertures is disposed opposite the first plurality of apertures, and sized to inhibit the flow of catalyst particles therethrough.

Abstract: Catalyst regeneration process and apparatus wherein air introduced to a midsection of a downwardly-moving mass of catalyst particles is taken off at the top and at the bottom of said bed through provided outlets and a third outlet is provided at the bottom portion of the said bed adapted to be controlled responsive to change in the flows through the top outlet and first mentioned bottom outlet to maintain substantially constant the total upward and downward flows through said bed. In an embodiment in which coke laydown on a hydrocarbon treated catalyst is burned off flue gases flow upwardly and out from the bed, e.g., through a carbon monoxide or flue gas burning boiler while downwardly flowing flue gas is taken off through a pressure control outlet or opening on which suction is taken by a blower passing flue gases to a boiler, a third outlet also flow controlled is operated responsive to change in the desired upward and downward flows of the flue gases.

Abstract: A catalytic reaction chamber for contacting a reactant stream with catalyst particles which are disposed as an annular-form bed and are downwardly movable therethrough via gravity-flow. The annular bed is spaced between a catalyst-retaining screen and a perforated centerpipe. A plurality of vertically-positioned catalyst-transfer, or withdrawal, conduits are circumferentially-disposed substantially adjacent the outer surface of the centerpipe and extend the entire length of the catalyst bed. These contain a first plurality of apertures which face into the bed of catalyst particles and which are sized to permit catalyst particles to flow therethrough. A second plurality of apertures is disposed substantially 180.degree. opposite the first plurality of apertures, and sized to inhibit the flow of catalyst particles therethrough.

Abstract: A catalytic reaction chamber for contacting a reactant stream with catalyst particles which are disposed as an annular-form bed and are downwardly movable therethrough via gravity-flow. The annular bed is formed between a catalyst-retaining screen and a perforated center-pipe. A plurality of vertically-positioned catalyst-transfer, or withdrawal, conduits are circumferentially-disposed substantially adjacent the outer surface of the centerpipe and extend the entire length of the catalyst bed. These contain a plurality of apertures which face into the bed of catalyst particles and which are sized to permit catalyst particles to flow therethrough. The use of these perforated catalyst-transfer conduits serves to alleviate the problems associated with the occurrence of stagnant catalyst areas which result from catalyst particles being "pinned" against the perforated centerpipe within the reaction zone, and unable to assume a downward flow pattern.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbonaceous charge stock and hydrogen flow serially through a plurality of catalytic reaction zones in each of which the catalyst particles are downwardly movable via gravity-flow. The flow of the product effluent from at least one reaction zone is restricted, as is the flow of the hydrogen-rich vaporous phase separated from the effluent from the last reaction zone and recycled to the first reaction zone. This technique increases the density of the reaction zone feed and the pressure drop within the entire reactor circuit, and thus serves to alleviate the problems associated with the occurrence of stagnant catalyst areas as a result of catalyst particles being "pinned" within the reaction zone and thus unable to assume a downward, gravity-flow pattern. Flow restriction may be effected either before, or after the inter-reaction zone heaters, preferably the former.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbonaceous charge stock and hydrogen flow serially through a plurality of catalytic reaction zones in each of which the catalyst particles are movable via gravity-flow. The flow of the product effluent from at least one reaction zone is restricted. This technique increases the pressure drop within the entire reactor circuit, and serves to alleviate the problems associated with the occurrence of stagnant catalyst areas as a result of catalyst particles being "pinned" within the reaction zone and thus unable to assume a downward gravity-flow pattern. Flow restriction may be effected either before, or after the inter-reaction zone heaters, preferably the former.

Abstract: A startup method for moving-bed reactors used in hydrocarbon conversion processes wherein the reactor is brought on-stream at full capacity while it contains less than a full loading of catalyst, and quantities of catalyst are intermittently added to the reactor while the hydrocarbons are being processed. Catalyst removal is then begun at a rate lower than the rate of catalyst addition and adjusted when the catalyst retention volume of the reactor becomes filled. The method is specifically adaptable to the hydrogenation of olefinic materials, the desulfurization of petroleum fractions and the production of liquid products from coal.

Abstract: An improved radial flow moving bed reactor, or other type of fluid-solid contacting vessel, in which stagnant catalyst volumes are reduced. The improvement results from the placement of a plurality of catalyst collection scoops or a single discoid cover plate just above the catalyst withdrawal conduits in a manner which directs the removal of catalyst through an annular opening adjacent the inner catalyst retention screen.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbonaceous charge stock and hydrogen flow serially through a plurality of catalytic reaction zones in each of which the catalyst particles are movable via gravity-flow. The reaction product effluent from each zone, in admixture with added hydrogen is heated prior to the introduction thereof into the succeeding reaction zone. The proportions of added hydrogen (portions of a recycled hydrogen-rich phase) are such that (i) vapor density decreases, and, (ii) lateral pressure drop across the catalyst bed increases in the direction of reactant stream flow through the plurality of reaction zones. The disclosed technique alleviates problems associated with the occurrence of stagnant catalyst areas as a result of catalyst particles being "pinned" within the reaction zone and thus unable to assume a downward gravity-flow pattern. In addition, the technique allows utilization of excess heater capacities before and between reaction zones.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbonaceous charge stock and hydrogen flow serially through a plurality of catalytic reaction zones, in each of which the catalyst particles are downwardly movable via gravity-flow. At least three reaction zones are utilized, with the fresh feed and hydrogen reactant stream being split between the first and second. The flow of that portion introduced into the second zone is restricted. Effluent flow from the first reaction zone is also restricted and combined with the effluent from the second reaction zone; the mixture is introduced into a third reaction zone. Where the catalytic conversion system consists of four reaction zones, the flow of effluent from the third is restricted prior to the introduction thereof into the fourth reaction zone.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbonaceous charge stock is reacted in a plurality of stacked catalytic reaction zones through which catalyst particles flow downwardly via gravity-flow. The charge stock, in the absence of added, or recycle hydrogen, is reacted first in the lowermost reaction zone, from which deactivated catalyst particles are withdrawn from the system. Resulting reaction zone effluent is further reacted in the uppermost reaction zone, through which fresh, or regenerated catalyst particles are introduced into the system, and serially in one or more subsequent, lower reaction zones. Product effluent from the reaction zone immediately above the lowermost zone is separated to recover the desired normally liquid product.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbon charge stock is countercurrently reacted in a plurality of catalytic reaction zones, in all of which the catalyst particles are downwardly movable via gravity-flow. The charge stock, in the absence of added, or recycled hydrogen, is reacted serially in the reaction zones in the order of increasing catalyst loading, the product ultimately being recovered from the effluent emanating from that reaction zone (1) into which fresh, or regenerated catalyst particles are introduced and, (2) which contains the greatest quantity of catalyst particles. Catalyst particles are transferred from one reaction zone to another in the order of decreasing catalyst loading, ultimately being withdrawn from the system through the reaction zone containing the least amount of catalyst particles.

Abstract: A multiple-stage catalytic conversion system in which a hydrocarbonaceous charge stock is reacted in a plurality of catalytic reaction zones, through all of which the catalyst particles flow downwardly via gravity-flow. The charge stock, in the absence of added, or recycled hydrogen, is reacted in the last reaction zone, from which deactivated catalyst particles are withdrawn for regeneration. The reaction product effluent emanating therefrom is further reacted in an intermediate reaction zone. Additional reaction of the product effluent, from the intermediate zone, is effected in the first reaction zone, through which fresh, or regenerated catalyst particles are introduced into the system. The effluent from the first reaction zone is separated to recover the intended product. The system may comprise three or more reaction zones in side-by-side relationship, with the catalyst particles being transported from the lower end of one zone to the upper end of the next succeeding reaction zone.

Abstract: An improved moving bed continuous catalytic cracking process for cracking hydrocarbon feedstocks, such as gas oil, in the absence of added hydrogen, which includes the use of a minute amount of dispersed platinum supported directly on a cracking catalyst. The trace of platinum induces a substantial increase in the heat efficiency with which coke on catalyst is converted to CO.sub.2 in the regenerator section with minimal or no detriment to the cracking reaction.