Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
  • B01J8/24—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique
  • B01J8/38—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique with fluidised bed containing a rotatable device or being subject to rotation or to a circulatory movement, i.e. leaving a vessel and subsequently re-entering it
  • B01J8/384—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique with fluidised bed containing a rotatable device or being subject to rotation or to a circulatory movement, i.e. leaving a vessel and subsequently re-entering it being subject to a circulatory movement only
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/16—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with particles being subjected to vibrations or pulsations
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/08—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles
  • B01J8/14—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with moving particles moving in free vortex flow apparatus
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
  • B01J8/1881—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles with particles moving downwards while fluidised
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
  • B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
  • B01J8/24—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique
  • B01J8/36—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique with fluidised bed through which there is an essentially horizontal flow of particles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/00002—Chemical plants
  • B01J2219/00027—Process aspects
  • B01J2219/0004—Processes in series
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/18—Details relating to the spatial orientation of the reactor
  • B01J2219/182—Details relating to the spatial orientation of the reactor horizontal
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2219/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
  • B01J2219/18—Details relating to the spatial orientation of the reactor
  • B01J2219/185—Details relating to the spatial orientation of the reactor vertical

Definitions

• the present invention relates to a rotating fluidized bed device and a fluid injection device in this rotating fluidized bed, within a fixed circular reaction chamber, and to catalytic polymerization, drying and drying processes. , impregnating, coating or other treatments of solid particles suspended in the rotating fluidized bed, or cracking, dehydrogenation or other catalytic conversion of fluids using this device.
• the centripetal pressure exerted by the fluid which flows radially through the fluidized bed can be substantially higher and therefore its flow rate and speed difference with that of Solid particles can be substantially higher, which improves the contact between the fluid and the solid particles and substantially increases the volume of fluid that can pass through the fluidized bed and thus also its ability to cool, heat and / or dry the solid particles.
• the rotating fluidized bed is supported by a fixed cylindrical wall along which it must slide, the pressure exerted by the solid particles against this fixed cylindrical wall brakes all the more these solid particles as the thickness, the density and the speed of rotation of the fluidized bed are large. The latter will decrease rapidly if the kinetic moment of rotation is not maintained by means of rotating mechanical means, with the problems related to the presence of mobile equipment inside a reactor, and / or by the injection of fluid, at high speed, in the direction of rotation of the fluidized bed.
• the amount of fluid that must be injected to transfer the required kinetic momentum to the solid particles is very large and can prevent the formation of a thick and dense fluidized bed and good separation of fluid and solid particles. Indeed, when a fluid is injected at high speed, tangentially to the cylindrical wall and perpendicular to the axis of symmetry of a cylindrical chamber through which a central chimney comprises evacuation openings for the evacuation of this fluid , the fluid can perform several turns around this central chimney before entering, if the evacuation openings are narrow. But, as soon as solid particles are introduced into this cylindrical chamber, they further inhibit the fluid as the ratio of the specific mass of the solid particles and the fluid is large.
• the evacuation of the fluid becomes more direct, which can even lead to a reversal of the flow of fluid along the central stack, downstream of the evacuation openings, and cause turbulence which causes the solid particles to exit. , thus limiting the possibility of forming a thick and dense fluidized bed within the cylindrical chamber.
• the formation of a rotating fluidized bed inside a reactor has various problems. It is an object of the present invention to provide an improved rotative fluidized bed device, and more particularly a rotary fluidized bed device which at least partially solves the aforementioned problems.
• the present invention aims to provide a rotating fluidized bed device in which the injection of one or more fluids is corrected, and wherein the formation of the fluidized bed is improved.
• the present invention provides a rotating fluidized bed device in which the injection of one or more fluids is improved by providing a fluid injection device adapted to inject one or more fluids into successive layers in said rotating fluidized bed. More particularly, the invention relates to a device with a rotating fluidized bed comprising: a cylindrical reactor comprising at least one cylindrical chamber, a device for supplying one or more fluids, gaseous or liquid, arranged around the circular wall said cylindrical chamber, a device for discharging said fluid or mixture of fluids, a device for feeding solid particles to one side of said cylindrical chamber and a device for evacuating said solid particles from the opposite side of said cylindrical chamber; said cylindrical chamber, characterized in that: o said device for discharging said fluid or mixture of fluids ⁇ mprends a central chimney passing longitudinally or penetrating inside said cylindrical chamber, the wall of said central chimney comprising at least one discharge opening allowing evacuating centrally, by said central chimney, the fluid or mixture of fluids from said cylindrical chamber; said feed device for said fluid or mixture
• the present invention provides the use of injectors, distributed around the circular wall of a cylindrical chamber (also called 'circular reaction chamber'), which inject one or more fluids, along the circular wall, in successive layers to form a succession of layers of fluid which are superimposed by rotating rapidly inside the reaction chamber, around a central chimney which penetrates or crosses along its central axis and which is provided with one or more discharge openings through which the fluid can be discharged centrally.
• injectors distributed around the circular wall of a cylindrical chamber (also called 'circular reaction chamber'), which inject one or more fluids, along the circular wall, in successive layers to form a succession of layers of fluid which are superimposed by rotating rapidly inside the reaction chamber, around a central chimney which penetrates or crosses along its central axis and which is provided with one or more discharge openings through which the fluid can be discharged centrally.
• the circular reaction chamber is traversed by a stream of solid particles which are fed from one of its sides and discharged from the opposite side and which are driven by the fluid in a fast rotational movement whose centrifugal force makes it possible to concentrate them before their exit from the circular reaction chamber, in a dense rotating fluidized bed, which is at least partially supported by the centripetal pressure of these successive layers of fluid which run along the circular wall and which act as fluid cushions, reducing the friction of the solid particles against this wall.
• the fluid is fed by a supply device which may comprise a fluid supply chamber surrounding the circular reaction chamber, the pressure difference, preferably greater than the average pressure due to the centrifugal force of the rotating fluidized bed against the circular wall, between the feed device and the central chimney and the flow rate of the fluid or fluids for supporting and rotating the fluidized bed at a speed generating a substantial average centrifugal force, preferably greater than three times the force of gravity .
• a supply device which may comprise a fluid supply chamber surrounding the circular reaction chamber, the pressure difference, preferably greater than the average pressure due to the centrifugal force of the rotating fluidized bed against the circular wall, between the feed device and the central chimney and the flow rate of the fluid or fluids for supporting and rotating the fluidized bed at a speed generating a substantial average centrifugal force, preferably greater than three times the force of gravity .
• the invention provides a rotating fluidized bed device in which the formation of the fluidized bed is further improved by adapting the internal dimension of the reactor, without losing capacity.
• the present invention provides in particular for dividing reactor in a succession of cylindrical chambers interconnected.
• the invention relates to a rotating fluidized bed device according to the invention, characterized in that it comprises hollow discs, perpendicular to the axis of symmetry of said reactor and fixed against the cylindrical wall of said reactor, dividing said reactor into a succession of cylindrical chambers interconnected by passages arranged through said hollow discs, allowing said solid particles in suspension in said rotary fluidized beds to pass from said cylindrical chamber to the other, and characterized in that said device for discharging said fluids or said includes said so-called hollow discs which are each provided with at least one central opening around said axis of symmetry and at least one lateral opening connected to at least one collector outside the reactor for discharging said fluids through said hollow discs and regulate the outlet pressures of said ch cylindrical amber.
• a cylindrical reactor is divided into a succession of cylindrical chambers by a succession of flat cylinders or hollow discs fixed against its side wall.
• These hollow discs include openings in their center to suck the fluid through each chamber by rotating quickly, and openings in their side wall to evacuate outside the reactor.
• These hollow discs are traversed by appropriately profiled passages to allow the solid particles in suspension in the fluid, rotating rapidly, to pass from one cylindrical chamber to another.
• the invention also provides a device with a rotating fluidized bed in which the injection of one or more fluids is further improved by providing an injection device to improve the efficiency of the transfer. of energy and momentum of said fluid to solid particles suspended in said rotating fluidized bed.
• the present invention provides at least one deflector capable of delimiting inside said rotating fluidized bed a space around one or more jets of said fluid directed in the direction of rotation of said rotating fluidized bed.
• the invention relates to a device with a rotating fluidized bed according to the invention, characterized in that the device for feeding one or more fluids comprises a device for injecting fluid into the interior of said bed.
• rotary fluidized fluidizer which fluid injection device comprises at least one deflector defining inside said rotating fluidized bed a space around one or more jets of said fluid directed in the direction of rotation of said rotating fluidized bed, from one or more injectors of said fluid, said baffle being arranged to delimit between said injector or injectors and said baffle, a passage or passageway to a flow of said solid particles suspended in the said fluidized rotating bed, from the upstream of said injector, to enter the said space in order to mix with the said fluid jets or said fluid, said space being long enough to perm said or said fluid jets yielding a substantial portion of their kinetic energy to said solid particles before reaching the exit of said space.
• the present invention to improve the efficiency of momentum transfer and of kinetic energy between a fluid jet and solid particles suspended in a rotating fluidized bed, comprises baffles, inside the rotating fluidized bed, suitably shaped and arranged near the injectors of the fluid, to allow mixing injected fluid with a limited amount of solid particles, while channeling it, to prevent or reduce its expansion in the reactor before it has transferred a significant amount of its kinetic energy to these solid particles.
• This device makes it possible to use much lighter fluids than solid particles and to inject it at high speed into the reactor without losing a large part of its kinetic energy because of its expansion in the reactor.
• a device according to the present invention can advantageously be used in different methods. Therefore, the present invention also relates to methods for catalytic polymerization, drying, impregnation, coating or other treatments of solid particles suspended in the rotating fluidized bed, or cracking, dehydrogenation or other catalytic transformations of fluids using this device.
• the invention relates to a process for the catalytic polymerization, drying or other treatments of solid particles suspended in a rotating fluidized bed or of catalytic conversion of fluids passing through said rotary fluidized bed, characterized in that comprises the steps of injecting one or more fluids, in successive layers, into a cylindrical chamber of a reactor, and evacuate them centrally by a central chimney flowing or penetrating into said cylindrical chamber, according to the present invention, at a flow rate and an injection pressure causing said solid particles at a mean rotational speed generating a centrifugal force at least three times greater than the force of gravity.
• the present invention also relates to a process for the catalytic polymerization, drying or other treatments of solid particles suspended in rotating fluidized beds or of catalytic transformation of fluids passing through rotating fluidized beds, characterized in that it comprises the steps which comprise injecting into a horizontal cylindrical reactor according to the present invention, a fluid or mixture of fluids at a rate and a flow rate giving said solid particles an average speed of rotation greater than the square root of the product of the reactor diameter and which is the acceleration due to gravity.
• the present invention also relates to a process for catalytic polymerization, drying or other treatments of solid particles suspended in rotary fluidized beds or catalytic conversion of fluids passing through rotating fluidized beds, characterized in that it comprises the steps of injecting into a vertical cylindrical reactor according to the present invention, a fluid or mixture of fluids at a speed and at a flow rate generating in the said rotating fluidized bed a centrifugal force greater than gravity, the said solid particles being transferred from a said chamber cylindrical to the other downward of said reactor.
• Another method according to the present invention relates to a method of catalytic polymerization, drying or other treatments of solid particles suspended in rotating fluidized beds or catalytic conversion of fluids through rotating fluidized beds, characterized in that it comprises the steps of injecting into a vertical cylindrical reactor according to the present invention, a fluid or mixture of fluids at a speed and a flow rate giving said solid particles an average speed of rotation greater than the speed they can acquire by falling from the top to the base of said cylindrical chambers and their allowing to pass from said lower cylindrical chamber to said upper cylindrical chamber by at least one passage arranged in said hollow disc separating them and oriented in the direction causing said solid particles to rise.
• the present invention also relates to the use of a device described in the present invention in a polymerization process.
• the present invention also relates to the use of a device described in the present invention in a process for catalytic transformation of a fluid or mixture of fluids passing through a rotating fluidized bed whose solid particles are catalysts.
• the present invention also relates to the use of a device described in the present invention in a process for drying or extraction of volatile components of said solid particles.
• a device according to the present invention may also be used in a process for impregnating or coating said solid particles.
• the present invention thus provides an improved rotary fluidized bed device, in which the injection of one or more fluids, and wherein the formation of the fluidized bed has been improved through various technical modifications, applied as such or in combination with each other, including inter alia, the use of injectors adapted to inject one or more fluids in successive layers in the reactor, the division of the reactor into several successive reaction chambers, and / or the use of an injection device provided with one or more deflectors.
• the present invention makes it possible to pass through a dense rotating fluidized bed, with a good separation between the solid particles and the fluid, by a very large amount of fluid and to rotate it rapidly to obtain a high centrifugal force, without the use of rotating mechanical means inside the reactor, even if the density of the fluid is low. It allows easy recycling, after appropriate treatment, fluid and / or solid particles, whose residence time can be adapted to the needs. It is particularly advantageous for processes which require a very good contact between the fluid and the solid particles, such as fast drying of solid particles in a compact reactor, and / or a large heat transfer capacity for controlling the temperature.
• very exothermic catalytic reactions such as the catalytic polymerization of ethylene or very endothermic catalysts such as the catalytic dehydrogenation of ethylbenzene or the catalytic cracking of light gasolines. It also allows regeneration of the catalyst particles at the desired rate and the high rotational speed of these solid particles reduces the likelihood that they will form agglomerates or adhere to the reactor surface. The presence of fluid cushions between the solid particles and the reactor surface also reduces the attrition of these solid particles and reactor walls.
• This method allows residence times of the particles in the reactor, short or long, depending on the size of the passages between the cylindrical chambers, and the resistance to rotation of the fluidized bed can be low because the injection of the fluid into thin films along the side wall of the reactor reduces the friction of the solid particles on this wall.
• This method is particularly advantageous when the volume of the circulating fluid is very high, because the central evacuation devices of the fluid by hollow discs can allow very large flow of the fluid with a minimum of resistance and the distributors and collectors of the fluid, being outside the reactor, can have large diameters without reducing the space available for the fluidized bed inside the reactor.
• This method is also particularly advantageous when the pressure inside the reactor is lower than atmospheric pressure, because the hollow discs can support the cylindrical wall of the reactor, which makes it possible to have thin walls, cut longitudinally, to form slots through which the fluid can be injected and to facilitate disassembly.
• the distributors, the collectors and the reactor can form a compact, easily transportable assembly.
• this process allows the construction of light, compact, transportable and efficient units, for example for the drying of cereal seeds. It is also suitable for catalytic modifications of low pressure fluids, such as cracking of light olefins or dehydrogenation of ethylbenzene which, being highly endothermic, require intermediate reheating and regeneration of the catalyst. It can also be used for the catalytic copolymerization, bi or multimodal, particles suspended in a succession of active fluids of different compositions. Other features and examples of devices according to the present invention are described below in a nonlimiting manner.
• FIG. 1 shows a schematic longitudinal section of a cylindrical reactor according to the invention comprising three concentric walls.
• FIG. 2 shows a schematic cross section, along the plane of the axes (y) and (z), of a cylindrical reactor according to the invention.
• Figure 3 shows the schematic cross section of an area around a fluid injector, illustrating how a small modification of the circular wall downstream of a fluid injector changes the orientation of the plane of its outlet.
• FIG. 4 shows the schematic transverse section, along the plane of the axes (y) and (z) of a reactor whose feeders and evacuation devices of the fluid or fluids of the reaction chamber have been modified.
• FIG. 5 shows an enlargement of the area around two fluid injectors.
• FIG. 6 shows the schematic longitudinal section, in the plane of the axes (x) and (z), the axis of (z) being vertical and coinciding with the axis of rotation (OO 1 ) of the fluidized beds, of the connection two sections of superimposed circular chambers.
• FIG. 7 shows a diagram adapted to the drying of solid particles introduced from a side of one of two circular reaction chambers placed in series.
• FIG. 8 represents the schematic diagram of a schematic longitudinal section of a reactor similar to that of FIG. 1, but whose axis of rotation of the fluidized bed is vertical or strongly inclined and whose central chimney ends at a certain distance above the lower side.
• FIG. 9 shows the diagram of a longitudinal section of a reactor similar to that of FIG. 1, comprising at each end of the central stack a centrifugal compressor.
• FIG. 10 represents an embodiment of the invention in which the feed chamber and the central stack of a cylindrical reactor according to the invention are divided into four sections.
• FIG. 11 shows a schematic view of a section of a vertical cylindrical reactor whose section of its cylindrical side wall is seen on each side of its cylindrical axis of symmetry.
• Figure 12 shows a cross section of a cylindrical reactor for viewing a preferred embodiment of a fluid injection device according to the invention.
• Figure 13 is an axonometric projection of a portion of the side wall of a reactor to better visualize fluid injection devices according to the invention.
• Figure 14 is the projection of a half cross section of a cylindrical chamber.
• Figure 15 shows the section of a particle transfer passage from one zone of a reactor to another zone.
• Figure 16 is a transverse flow diagram of the solid particles along a half longitudinal section of a cylindrical chamber similar to that shown in Figure 14, without the side and central baffles.
• Figure 17 illustrates a simplified diagram, similar to Figure 11, slightly modified to allow for bimodal or multimodal co-polymerization.
• FIG. 18 illustrates a simplified diagram, similar to that of FIG. 17, slightly modified to allow the catalytic conversion of a fluid or mixture of fluids in a rotating fluidized bed containing solid catalyst particles.
• Figure 19 shows the longitudinal section of a horizontal reactor, which can work at a pressure slightly lower than atmospheric pressure.
• FIG. 20 represents the view of a section crossing a hollow disk, along the plane AA 'of FIG. 19, for a reactor having two distributors and two collectors and forming therewith a compact assembly that is easily transportable and designed to be easily removable.
• Fig. 21 is an enlargement of the fluid injection device shown in Figs. 19 and 20.
• Figure 22 shows the view of a section along the plane BB 'perpendicular to Figure 20, the nozzle connecting a hollow disk to a collector.
• the present invention relates to an improved fluidized bed device.
• a device generally comprises a cylindrical reactor containing one or more circular reaction chambers.
• the terms "circular reaction chamber” and “cylindrical chamber” are used in some embodiments of the present invention as synonymous and refer to a chamber within the cylindrical reactor.
• the terms "circular wall” and “cylindrical wall” indicating the wall of the circular reaction chamber or the cylindrical chamber are used in some embodiments of the present invention as synonyms.
• the present invention relates to a rotating fluidized bed device comprising a fluid injection device, capable of injecting one or more fluids in successive layers, inside a fixed circular reaction chamber. , and processes for catalytic polymerization, drying, impregnation, coating or other treatments of solid particles suspended in the rotating fluidized bed, or cracking, dehydrogenation or other catalytic conversion of fluids using this device.
• the present invention relates to a fluid injection device in successive layers in a rotating fluidized bed and catalytic polymerization process, drying or other solid particle treatment or catalytic transformation of fluids, where a succession of injectors distributed around the fixed circular wall of a circular reaction chamber, injecting along this wall, in successive layers, one or more fluids, which entrain the solid particles, passing through this chamber, in a rotational movement This centrifugal force concentrates these particles along this wall, thus forming a fluidized bed rotating around a central chimney, through which the fluids are evacuated.
• injectors distributed around the circular wall of a circular reaction chamber, inject one or more fluids, along the circular wall, in successive layers, in order to form a succession of layers of fluid which superimposed by rotating rapidly inside the reaction chamber, around a central chimney that penetrates or crosses along its central axis and which is provided with one or more discharge openings through which the fluid can be evacuated centrally.
• the circular reaction chamber is traversed by a stream of solid particles which are fed from one of its sides and discharged from the opposite side and which are driven by the fluid in a fast rotational movement whose centrifugal force makes it possible to concentrate them before their exit from the circular reaction chamber, in a dense rotating fluidized bed, which is at least partially supported by the centripetal pressure of these successive layers of fluid which run along the circular wall and which act as fluid cushions, reducing the friction of the solid particles against this wall.
• the fluid is fed by a supply device which may comprise a fluid supply chamber surrounding the circular reaction chamber, the pressure difference, preferably greater than the average pressure due to the centrifugal force of the rotating fluidized bed against the circular wall, between the feed device and the central chimney and the flow rate of the fluid or fluids allowing the support and rotating the fluidized bed at a rate generating a substantial average centrifugal force, preferably greater than three times the force of gravity.
• a supply device which may comprise a fluid supply chamber surrounding the circular reaction chamber, the pressure difference, preferably greater than the average pressure due to the centrifugal force of the rotating fluidized bed against the circular wall, between the feed device and the central chimney and the flow rate of the fluid or fluids allowing the support and rotating the fluidized bed at a rate generating a substantial average centrifugal force, preferably greater than three times the force of gravity.
• the present invention relates to a rotating fluidized bed device comprising a circular reaction chamber, a device for supplying one or more fluids, arranged around the circular wall of said circular reaction chamber, a device for discharging said fluid or fluids, a device for feeding solid particles to one side of said circular reaction chamber and a device for discharging said solid particles on the opposite side; of said circular reaction chamber, characterized in that said device for discharging said fluid or said fluid includes a central duct passing longitudinally or penetrating inside said reaction chamber, the wall of said central duct comprising at least one evacuation opening enabling said fluid chamber (s) to be evacuated centrally through said central chimney; circular reaction; said feeder of said fluid or fluids comprises fluid injectors distributed around said circular wall for injecting said fluid or said fluids into a succession of layers which follow said circular wall by turning around said chimney central and driving said solid particles in a rotational movement whose centrifugal force pushes them towards said circular wall; said centrifugal force is, on average,
• each annular slice of the reaction chamber there be at least one fluid injector every 90 °, ie 4, and preferably at least seven, the most preferred being at least 11 and therefore the number of successive layers of fluid is high, or the distance between these injectors is small, preferably less than the average radius of the circular chamber, to limit the amount and concentration of the solid particles which come into contact with this circular wall after having passed through the layer of fluid which has been injected by the injector situated upstream, before reach the fluid layer injected by the injector located downstream.
• the profile of the injectors is designed so as to be able to inject the fluid at a sufficient speed, preferably at least twice the desired rotation speed for the solid particles in the fluidized bed, and in thin layers, with a thickness at the moment of their injection preferably less than one twentieth of the average radius of the chamber of reaction, in a direction forming an acute angle, preferably less than 30 °, with the circular wall, and that the planes of the outlet openings of the fluid injectors form with the side of the circular wall located downstream preferably included angles between 60 ° and 120 °, so that the thrust of the fluid or fluids at the time of their exit from the injectors is more tangential than radial or centripetal.
• the circular wall may be cylindrical, but it may also have different radii of curvature or be flat between the fluid injectors. In the latter case the circular wall is polygonal and its sides located on either side of the injectors form an angle all the closer to 180 ° as the number of injectors is high.
• the present device is in one embodiment, characterized in that the directions of injection of the layers of said fluid or said fluid injectors form an angle less than 30 ° with said circular wall of the side located downstream of said fluid injectors.
• the device according to the present invention is characterized in that the planes of the outputs of said fluid injectors form angles between 60 ° and 120 ° with said circular wall on the side downstream of said fluid injectors.
• the device according to the present invention is characterized in that each annular slice of said circular wall contains at least one said fluid injector every 90 °.
• the present device is characterized in that the distance between two so-called consecutive fluid injectors is preferably less than the average radius of said circular wall.
• the device according to the present invention is characterized in that the outputs of said fluid injectors are thin, preferably of a width less than one twentieth of the average radius of said reaction chamber.
• the present invention also relates to a device characterized in that the surface of said circular wall between two said consecutive injectors is flat, the circular wall being polygonal.
• no cross section of the central chimney comprises more than one fluid discharge opening, and that these openings are narrow, arranged longitudinally, preferably of an average width less than half the average distance between the central chimney and the circular wall and that the sum of the sections of the discharge openings is preferably less than twice the sum of the sections of the outlet openings of the fluid injectors, which is itself preferably less than half the longitudinal section of the circular reaction chamber, and that the planes of these discharge openings form with the wall of the chimney It preferably has an angle of between 60 ° and 120 °, this wall progressively deviates from the circular wall of the reaction chamber from its side downstream of the discharge openings to the opposite side, thereby taking the appearance of a spiral.
• the device according to the present invention is characterized in that the or said evacuation openings are disposed longitudinally and that their average width is less than half the mean distance between said wall of said central chimney and said circular wall.
• the device according to the present invention is characterized by in that the sum of the sections of said evacuation openings is less than twice the sum of the output sections of said fluid injectors.
• the device according to the present invention is characterized in that the planes of said evacuation openings form angles between 60 ° and 120 ° with the wall of said central chimney.
• the device according to the present invention is characterized in that no cross section of said central chimney passes through more than one said discharge opening.
• the present invention may comprise at least one deflector, wing-shaped, longitudinally passing through the reaction chamber, near the wall of the central chimney, having its leading edge upstream of the evacuation opening or openings of the fluid and its trailing edge downstream of these fluid discharge openings, in order to reintroduce into the reaction chamber the solid particles, generally the finest, which have entered the space between the baffle and the wall of the central fireplace.
• the inlet section of this space is preferably larger than the sum of the sections of the exhaust openings and the distance between the trailing edge and the wall of the central stack is preferably less than half the distance between this edge and the circular wall.
• This deflector may be hollow and provided with fluid injectors arranged along its trailing edge, in order to inject at a high speed, a thin layer of fluid, approximately parallel, preferably more or less than 30 °, to the wall of the central chimney, downstream of the discharge openings, to prevent these solid particles to go up along the wall of the central chimney downstream of the discharge opening. Therefore, in another embodiment, the device according to the present invention is characterized in that said reaction chamber is traversed longitudinally by at least one deflector, wing-shaped, close to said central chimney upstream of at least one of said evacuation openings and extending beyond the said evacuation openings.
• the device according to the present invention is characterized in that said deflector is hollow and is supplied with fluid by said fluid supply device and is provided with at least one fluid injector along its trailing edge for injecting said fluid in a thin layer along the wall of said central chimney downstream of said discharge opening.
• the device according to the present invention is characterized in that the distance between said edge located downstream of said hollow deflector and the wall of said central chimney located downstream of said evacuation opening is less than half the distance between said edge and said circular wall.
• the present invention may comprise at least one control transverse ring, which is placed near the exit of the solid particles, the outer edge of which runs along and is fixed to the circular wall and whose inner edge surrounds and is at an average distance from the central chimney, preferably greater than a quarter of the mean distance between the central chimney and the circular wall, in order to allow the solid particles to pass from one side of the fluidized bed to the other without too close to the evacuation openings of the central fireplace.
• This regulation ring makes it possible to prevent or slow down the transfer of the solid particles situated upstream of this ring downstream, as long as the fluidized bed has not reached the desired thickness upstream.
• This The ring may comprise a passage along the circular wall, to allow a minimum passage sufficient to gradually empty the circular reaction chamber when the supply of solid particles is stopped.
• the device according to the present invention is characterized in that said circular reaction chamber contains, near the side of said device for discharging said solid particles, a control ring. whose outer edge runs along and is fixed to said circular wall, and whose inner edge is at an average distance from said central chimney greater than a quarter of the average distance between said central chimney and said circular wall, said particles suspended solids in said rotating fluidized bed to pass into the space between said inner edge and said central chimney to pass from one side of said control ring to the other side.
• the device according to the present invention is characterized in that said regulation ring comprises at least one passage, located against said circular wall, for the transfer of said solid particles located on one side of the said separation ring to the other side without having to go through the space between said inner edge and said central chimney.
• the present invention may comprise a set of helical coils, whose outer edges run along and are fixed to the circular wall and whose inner edges surround and are at an average distance from the central stack, preferably greater than one quarter of the average distance between the central chimney and the circular wall, in order to allow the solid particles which move longitudinally in one direction, as they run along these helical turns, to move in the other direction in the space between these helical coils and the central chimney without getting too close to the openings of the central chimney.
• helical coils which can form a continuous helical helix or discontinuous or be fragmented into a set of fins, make it possible to pass the solid particles from one side to the other of the circular reaction chamber many times and / or to raise them longitudinally, if the axis of rotation of the fluidized bed is inclined or vertical. Similar devices are described in Applications Nos. 2004/0186 and 2004/0612 of Belgian patents, filed on April 14 and December 12, 2004 in the name of the same inventor.
• the device according to the present invention is characterized in that said circular reaction chamber contains a set of turns or fraction of helical turns whose outer edge runs along and is fixed to the said circular wall, and whose inner edge is at an average distance from said central chimney greater than a quarter of the average distance between said central chimney and said circular wall.
• the axis of rotation of the fluidized bed can be horizontal, inclined or vertical. If it is horizontal or inclined less than 45 °, preferably less than 30 °, the average velocity of the solid particles, their concentration and the pressure they exert on the thin layers of fluid are higher in the bottom of the reaction chamber. It is therefore preferable to divide the outer distribution chamber into several longitudinal sectors by longitudinal separation walls in order to be able to differentiate the fluid injection pressure in the different fluid injectors as a function of their position in the reaction chamber.
• separation rings surrounding the central chimney at a distance from it, preferably less than one third of the average distance between the circular wall and the central chimney to allow the solid particles to pass into this space without too close to the discharge opening of the central chimney, can be fixed against the circular wall to prevent the rapid fall of the solid particles.
• the pressure exerted by these solid particles against the upper surface of these separation rings will slow them down not only in their fall, but also in their rotational movement. This can be compensated, if necessary, if these rings are hollow and provided with fluid injectors for injecting a fluid in thin layers along their upper surface in the direction of rotation of the solid particles.
• these separating rings may be replaced by helical coils, which may also be hollow and which may form a continuous helical helix or discontinuous or be broken up into fins, fixed against the circular wall, the orientation of the slope of the turns or fins driving up the solid particles, which rotate rapidly along the circular wall, and the average distance between the inner edge of the turns and the central chimney, preferably greater than a quarter of the average distance between the circular wall and the central chimney, allowing the solid particles, which are mounted along the upper surface of these turns, to fall into this space without too close to the discharge opening of the central chimney.
• This makes it possible to feed the solid particles into the bottom of the circular reaction chamber and to evacuate them at the top.
• Similar devices are described in Applications Nos. 2004/0186 and 2004/0612 of Belgian patents, filed on April 14 and December 12, 2004 in the name of the same inventor.
• the device according to the present invention is characterized in that the axis of rotation of said fluidized bed forms an angle less than 45 ° with the vertical and in that said central chimney crosses the side upper of said circular reaction chamber and ends at a distance from the opposite side, the cross section of said central chimney gradually decreasing from the top down.
• the device according to the present invention is characterized in that the average radius of said circular reaction chamber decreases gradually from the top downwards.
• the device according to the present invention is characterized in that the axis of rotation of said fluidized bed forms an angle less than 45 ° with the vertical and in that said circular reaction chamber comprises separating rings, dividing the said fluidified rotating bed into several annular sections, the outer side of said separation rings running along and being fixed to said circular wall and their inner edge being at an average distance from said central stack greater than a quarter of the mean distance between said central chimney and said circular wall, said solid particles suspended in said rotating fluidized bed to pass into the space between said inner edge and said central chimney to pass from one side of said one of the so-called separation rings on the other side.
• the device according to the present invention is characterized in that said separation rings are hollow and are supplied with fluid by said supply device, said fluid being injected in a succession of layers along the upper surfaces said rings in the direction of rotation of said rotating fluidized bed.
• the device according to the present invention is characterized in that the said separation rings comprise at least one passage, situated against the said circular wall, allowing the passage of the said solid particles situated above said separation rings down without having to pass through the space between said inner edges and said central chimney.
• the device according to the present invention is characterized in that said separation rings are spiral turns or fraction of helical turns, whose slope is oriented upwards.
• the device according to the present invention is characterized in that the axis of rotation of said fluidized bed forms an angle greater than 45 ° with the vertical and in that the or said evacuation openings is or are located on the side of the lower longitudinal portion of said circular reaction chamber.
• the device according to the present invention is characterized in that the axis of rotation of said fluidized bed forms an angle greater than 45 ° with the vertical and in that the leading edge of said deflector is located on the side of the lower longitudinal portion of said circular reaction chamber.
• the central chimney may pass only one side of the circular reaction chamber, preferably the upper side if the axis of rotation of the fluidized bed is vertical or inclined, and terminate before reaching the side. opposite.
• the cross section may gradually decrease and its end located in the circular reaction chamber may be open or closed.
• the wall of said central chimney is flared at at least one of its two ends and in that it comprises a discharge tube of said fluid, concentric and at a distance from said flared wall, and a discharge tube against said flared wall separately discharging said solid particles which have been entrained in said central chimney and which are pushed by the centrifugal force along the said flared wall.
• the distribution chamber can be divided into successive annular sections by transverse annular separation walls in order to be able to differentiate the quality and the quantity of the fluids which are fed into the different sections and which cross the corresponding section of the fluidized bed.
• the device according to the present invention is characterized in that said feeder said fluid or said fluid comprises a fluid supply chamber surrounding said circular wall, the difference pressure between said fluid supply chamber and said central chimney being maintained by said devices for supplying and discharging said fluid (s) at more than once the pressure mean centrifuge exerted by said fluidized bed on said circular wall.
• said feed chamber is divided into longitudinal sectors by longitudinal walls for feeding said injectors corresponding to said longitudinal sectors at different pressures. your.
• the device according to the present invention is characterized in that said feed chamber is divided into successive annular sections by transverse annular walls for separately feeding the said injectors corresponding to each of said sections successive annular and thus to cross the corresponding annular sections of said rotating fluidized bed with fluids of compositions and / or at different temperatures and / or injection rates.
• the device according to the present invention is characterized in that said device for supplying one or more fluids comprises at least one ejector penetrating into a discharge pipe of said fluid or fluids and by where said one or more feed fluids are injected at a very high speed and mixed with the fluids discharged into said exhaust duct for recycling into said circular reaction chamber.
• a plurality of circular reaction chambers can be put in series by connecting the solid particle outlet of a chamber to the inlet of the solid particles of the next chamber, and the solid particles can be recycled after being regenerated. if they are catalytic, by a suitable device after having spent a longer or shorter time, as needed, in the circular chamber or chambers of reaction.
• the device according to the present invention is characterized in that the said circular reaction chamber is connected to another similar chamber by a transfer conduit which makes it possible to transfer the said solid particles from the said circular chamber of reaction to the said similar chamber and whose inlet is located near the said circular wall of the said circular reaction chamber, the opposite side to said supply device of said solid particles, and whose output is located near of said central chimney of said similar chamber on the opposite side to said device for discharging said solid particles from said similar chamber.
• a transfer conduit which makes it possible to transfer the said solid particles from the said circular chamber of reaction to the said similar chamber and whose inlet is located near the said circular wall of the said circular reaction chamber, the opposite side to said supply device of said solid particles, and whose output is located near of said central chimney of said similar chamber on the opposite side to said device for discharging said solid particles from said similar chamber.
• the device according to the present invention is characterized in that said central chimney is divided transversely by transverse walls in sections connected to discharge tubes disposed inside said central chimney allow separately evacuate the fluids from said sections of said central stack and recycle and treat separately in a corresponding section or another section of said circular reaction chamber.
• the device according to the present invention is characterized in that said circular reaction chamber is divided into annular sections corresponding to said sections of said central chimney, by annular walls fixed between said circular wall and said central chimney, said annular walls comprising at least one passage against said circular wall.
• the device according to the present invention is characterized in that it comprises a device for recycling the fluid or said fluids evacuated by said device for discharging said fluid (s) towards said device. supply of said fluid or fluids, said recycling device comprising a treatment device of said recycled fluids for adjusting the temperature and / or the composition of said recycled fluids.
• the device according to the present invention is characterized in that it comprises a device for recycling said solid particles discharged by said evacuation device of said solid particles for recycling in said chamber circular reaction by said feeding device of said solid particles.
• the device according to the present invention is characterized in that said solid particles are catalysts and in that said device for recycling said catalytic particles comprises a device for regenerating said catalytic particles.
• the device according to the present invention is characterized in that the one or more said fluids are gases and in that it comprises a device for injecting a liquid, passing through said central chimney. , for spraying said liquid into fine droplets on at least a portion of the surface of said fluidized bed.
• FIG. 1 shows the schematic longitudinal section, in the plane of the axes (x) and (z), the axis (x) coinciding with the axis of rotation of the fluidized bed (00 ') and the axis (z), directed upwards, coinciding with the vertical, a cylindrical reactor comprising three concentric walls, the outer wall (1), the central wall, called the circular wall (2) and the central wall (3), called the wall of the central chimney, the space between the outer wall and the central wall being closed by two annular side walls (4.1) and (4.2).
• the space (5) between the outer wall and the circular wall is the supply chamber of the fluid or fluids
• the space (6) between the circular wall and the central wall is the circular reaction chamber
• the space to the interior of the central wall is the central chimney (7).
• Tubes (8) make it possible to introduce the fluid or fluids, symbolized by the arrows (9) through the outer wall (1) or the annular lateral walls (4.1) and (4.2), inside the the feed chamber (5) and the tubes (10) make it possible to evacuate the fluid or fluids, symbolized by the arrows (11), from the central chimney (7).
• the tangential component of their speed is much greater than the radial component, but it is not visible because it is perpendicular to the plane of the figure.
• a conduit (16) is used to introduce solid particles, symbolized by small circles (17), through the side wall (4.1).
• the solid particles are driven by the fluid in a rotational movement and the centrifugal force holds them along the circular wall (2) where they form an approximately cylindrical surface fluidized bed (18).
• a conduit (19) discharges the solid particles (17) through the opposite annular sidewall (4.2).
• Annular walls (20) can divide the distribution chamber (5) into annular sections (A), (B) and (C) in order to be able to supply different qualities and / or pressures to the fluid (s).
• the tubes (10) for discharging the fluid or fluids can penetrate inside the central chimney (3) which widens at its two ends, thus forming a kind of cyclone.
• the solid particles, which have been able to penetrate inside the central chimney and which turn rapidly, are concentrated along the conical walls (24), and are evacuated by the tubes (25) and possibly recycled.
• the fluidized bed may be divided by a regulating ring (26) optionally provided with one or more passages (27) against the circular wall allowing the solid particles to pass from one side to the other. If the feed rate of the solid particles (17) through the conduit (16) is higher than the transfer rate of the solid particles through the passages (27), the thickness (28) of the fluidized bed upstream of the The control ring (26) will increase until it is sufficient for the particles to overflow through the center of this ring to pass to the other side. And if the output rate of the solid particles through the conduit (19) is greater than the feed rate, the thickness (29) of the fluidized bed downstream of the regulating ring (26) will decrease until that the rarefaction of the solid particles automatically adjusts the output flow rate with the input flow rate of these particles.
• This device makes it possible to maintain the volume of the fluidized bed upstream of the control ring (26), preferably located near the outlet (19), approximately constant if the feed rate of the solid particles is sufficiently high.
• the passages (27) also make it possible to evacuate all the solid particles from the circular reaction chamber when the feeding of the solid particles is stopped. Since the reactor is horizontal, the effect of the force of gravity generates a difference in thickness of the fluidized bed and / or concentration of the solid particles between the top (28) and the bottom (30) of the circular reaction chamber.
• the outlet (14) is preferably in the bottom of the reactor because the speed and the concentration of the particles is maximum, and therefore the thickness of the fluidized bed is minimum, which reduces their probability of being driven into the central stack (7).
• the circular wall (2) is cylindrical in this illustration, and therefore its radius (33) is constant, while the radius of curvature of the wall of the central chimney (3) is variable. It is minimum (34) upstream of the output (14) and maximum (35) downstream.
• the width (36) of the discharge opening (14) can be maximum in the middle of the reaction chamber and minimum near the annular side walls (4.1) and (4.2) so that the cross section of the central chimney is more raised at its ends, to facilitate the evacuation of the fluid (11). It should be noted that this width (36) is preferably zero against these walls, to prevent the solid particles slowed by these walls are driven into the central chimney.
• the reactor can be slightly inclined to increase the flow of particles to their outlet and thus reduce their residence time inside the reaction chamber.
• the surface of the fluidized bed is slightly conical depending on the importance of the inclination and the ratio between the force of gravity and the centrifugal force.
• FIG. 2 shows the schematic cross-section along the plane of the axes (y) and (z) of the reactor of FIG. 1, in which the annular distribution chamber (5) is replaced by four tubular distribution chambers (5.1). ) to (5.4), each connected to an injector or set of fluid injectors (12). This arrangement may be preferred when the number of injectors is low.
• the radius of curvature (35) of the wall (3) of the central chimney is smaller (34) on its part upstream of the discharge opening (14), giving it the appearance of a spiral, and that the width (31) of the circular chamber is preferably smaller downstream than upstream (32), because the flow rate of the fluid rotating around the chimney increases as and when it approaches the evacuation opening (14).
• the surface (37) schematizes the section of a zone of turbulence generated by the possible inversion of the flow of the fluid, shown schematically by the arrows (38), downstream of the outlet (14) of the central chimney.
• This turbulence can cause the evacuation of solid particles, usually the finest, through the discharge opening (14).
• the force of gravity which adds to the centrifugal force in the bottom of the reactor and which increases the speed of the solid particles and therefore the centrifugal force, generates a higher pressure against the circular wall, this may justify a higher injection pressure in the tubular distribution chamber (5.3).
• the numerical simulation shows that it is possible, in a cylindrical chamber 40 cm in diameter with 4 fluid injectors, injecting air at atmospheric pressure in a direction forming an angle of 30 ° with the cylindrical wall, distributed, at a rate of one every 90 °, around each annular slice of the cylindrical chamber, to form a rotating fluidized bed dense.
• a large quantity of solid particles passes through the thin layers of fluid and is braked along the circular surface upstream of the injection slots, where their concentration approaches the theoretical maximum, which increases the resistance to the rotation of the fluidized bed.
• injectors can locally generate a strong centripetal thrust, which can project the solid particles to the discharge opening if the strong thrust is upstream of the discharge opening and thus lead to losses of solid particles.
• the injectors and the circular wall a shape that minimizes the centripetal thrust of the fluid and promote its tangential thrust.
• the planes of the outlet openings of the injectors are almost identical with the planes parallel to the circular surface which is cylindrical, which favors the centripetal thrust due to the pressure of the fluid on the solid particles even if the angle fluid injection is small.
• FIG. 3 shows the schematic cross section of the zone around a fluid injector, illustrating how a small modification of the circular wall (2.2) downstream of a fluid injector (12), which becomes flat and tangential.
• in (B) at the extension of the circular wall (2.3), changes the orientation of the plane of its outlet, which therefore forms an angle (40) of about 90 ° with the plane wall (2.2).
• the thrust generated by the high pressure of the fluid (13.1) on the upstream side of its outlet, in (A), is therefore more directed tangentially to the circular wall.
• the solid particles, highly concentrated, symbolized by small circles (17), form a compact assembly that slides along the circular wall (2.1) in the direction (41.1) upstream of the injector (12.1).
• the pressure of the fluid in the space (43) between the wall (2.2) and the flow line (41.2) of the solid particles must be sufficient to prevent the solid particles from clogging the outlet of the fluid and thus to deflect them according to this flow line (41.2).
• This illustration shows how the solid particles braked by the curved wall of the reaction chamber and, encountering the obstacle constituted by the injection of a jet of fluid, can form a compact assembly which substantially slows the normal sliding of these particles. solid particles and how the arrangement and orientation of the injector outlet opening and the fluid injection direction can minimize this braking and the centripetal pressure exerted by the fluid on the solid particles upstream of its outlet .
• FIG. 4 shows the schematic cross-section along the plane of the axes (y) and (z) of a reactor whose feed and discharge devices for the fluid or fluids of the reaction chamber have been modified to improve the proportion between the transfer of tangential and centripetal kinetic momentum of the fluid to the solid particles and to reduce the amount of solid particles escaping through the discharge opening (14) of the central chimney.
• the feed chamber is preferably delimited by a cylindrical wall (1) surrounding the circular wall (2) and is divided into longitudinal sectors of (5.1) to (5.4), by longitudinal walls (49), to allow to supply the different fluid injectors (12) at different pressures.
• the circular wall is flat between two injectors (12). It is therefore polygonal.
• the fluid is injected parallel to this surface, according to the diagram described in FIG. 5, in order to facilitate the sliding of the solid particles along the latter and to reduce their concentration upstream of the injection slots and thus to reduce the resistance. to advancement.
• the turbulence zone (37) which can develop along the leading edge (54) of the deflector (50) can cause solid particles in this space (53).
• the distance (51) being preferably greater than the thickness (36) of the discharge opening (14), the speed of the fluid (52), which accelerates these solid particles, increases gradually and the centrifugal force pushes them along the curved inner wall (55) of the hollow baffle (50).
• the trailing edge (56) of the deflector located at the distance (57) from the wall of the central chimney (3), is provided with one or more fluid injectors for injecting a thin layer of fluid at high speed. (58) more or less parallel, preferably within 30 °, to the wall of the central chimney (3), producing a suction effect which leads back into the chamber of reaction (6), beyond the discharge opening (14), the solid particles which run along the inner wall (55) of the deflector.
• a turbulence zone (59.1) can develop between the thin fluid layer (58) and the wall of the central chimney (3) and generate a flow reversal which brings part of these particles back to the outlet (14) .
• the pressure drop in the space (53) is small and therefore that the quantity of solid particles that the fluid stream (52) must accelerate is small and that the distance (57) is small, preferably less than half the distance (60) between the trailing edge and the circular wall.
• Another turbulence zone (59.2) may develop between the fluid jet (58) and the circular wall and cause a reversal of the fluid flow which increases the resistance to rotation of the fluidized bed upstream of this zone.
• the injection of the thin layer of fluid (58) is parallel or slightly directed towards the wall of the central chimney (3).
• Figure 5 shows an enlargement of the area around the two injectors (12.1) and (12.2).
• the solid particles form a barrier, which acts as a more or less permeable deflector depending on their concentration, and they confine the fluid between the flow line (42.2) and the polygonal wall (2.2) and the medium which keeps a high average speed, because it is confined in a narrow space, loses energy and therefore pressure as it transfers it to the solid particles along the flow line (41.3), accelerating them and thus decreasing their concentration. and their permeability increases, allowing the flow line (42.3) to move away from the wall (2.2) and thus the fluid, which has lost a lot of its energy, to slow down.
• the flow line (41.4) of the solid particles finished along the wall (2.2), along which they slide, slow down and their concentration increases before reaching the next injector (12.2). And so on ...
• the concentration of the flow of solid particles upstream of the injectors is even greater than the distance between the fluid injectors (12.1) and (12.2) is large and therefore their number is small, and if the surface of the plane wall (2.2) were curved like the walls (2.1) and (2.3) in Figure 3, it would exert on the flows of solid particles (41.1) and (41.4) an additional pressure which would slow them down and which This would increase their concentration and the resistance to rotation of the fluidized bed.
• the angle of deflection (66) between two injectors is smaller as the number of injectors is high, which decreases the deflection of the solid particle streams (41.2) and (41.3) and thus the pressure exerted on them. on the fluid flows (13.1) and (13.2) and therefore also the amount of solid particles that can be concentrated along the polygonal circular wall after passing through these fluid flows and thus also the resistance to rotation of the fluidized bed.
• the angle (40) formed by the plane of the outlet of the injector (12.1) and the polygonal circular wall (2.2) is approximately 90 °, which makes it possible to inject the fluid (13.1) in a direction almost parallel to this wall (2.2) and thus to increase the amount of tangential kinetic momentum transferred to the solid particles.
• the circular reaction chamber can be connected in series with other similar chambers, the outlet (19) of the solid particles of the upstream chamber being connected to the inlet (16) of the next chamber.
• These circular reaction chambers can be side by side, in the extension of one another or superimposed. They can be inclined or vertical.
• FIG. 6 shows the schematic longitudinal section, in the plane of the axes (x) and (z), the axis of (z) being vertical and coinciding with the axis of rotation (OO 1 ) of the fluidized beds, of the connection two sections of superimposed circular chambers. Since the surfaces (18) of the fluidized beds are conical, the fluidized beds of the reaction chambers (6) are subdivided into annular sections by separation rings (80) which support the portion of the fluidized bed directly above them. These are hollow and connected to the fluid distribution chambers (5) through openings (81) so that they can be injected by injectors (82) more or less parallel to the plane of the axes (x) and (y) and perpendicularly. at the axis of rotation (00 '), fluids, symbolized by the arrows (83), in thin layers, which support and rotate the solid particles which rest on the upper part of the separating rings (80 ).
• the separation ring (85) at the bottom of the reaction chambers is extended to the wall of the central chimney (3), while the other separation rings (80) have a wide central opening, preferably greater than a quarter of the average distance between the circular wall and the central chimney, to allow the solid particles to pass through while remaining at a certain distance from the wall of the central chimney (3) so as not to be dragged into the chimney central through the discharge opening (14).
• the fluid flows (11) are evacuated from the central chimneys (7) by one or more conduits (93).
• the pressure at the inlet of the transfer duct (91), located inside the fluidized bed , close to the circular wall is greater than the pressure at its outlet, situated outside the fluidized bed, near the wall of the central chimney, which facilitates the transfer of the solid particles from one reactor to the other, even when the reactors are horizontal and located at the same height.
• the separation rings (85) can be replaced by helical turns.
• the solid particles that rotate along the circular wall and a helical turn will rise if the slope of the coil is in the upward direction. In this case it is possible to transfer the solid particles from the lower chamber to the upper chamber, if the lower part of the transfer duct (91) is located along the circular wall where the pressure is highest and the upper part this duct (91) is located against the central chimney where the pressure is the lowest. Particles that are not transferred or removed from the top of the circular reaction chamber may fall back into the central space between the inner edge of the turns and the central stack.
• the helical coils may also be hollow and fed with fluid which is injected along their upper surface into the circular reaction chamber. They may form a continuous or discontinuous helical helix or be fragmented into a fraction of turns, similar to fixed fins, oriented in the ascending direction.
• FIG. 7 shows a diagram adapted to the drying of solid particles introduced by the tube (16) on one side of one of the two circular reaction chambers placed in series and exiting through the tube (19) placed at the end opposite of the second chamber, the transfer of these particles from one reactor to another is via the transfer conduit (91).
• the fresh and dry gas (100) is introduced through the tube (8.1) feeding the annular section (F) of the feed chamber located on the side of the outlet (19) of the solid particles. It is heated in contact with the hot solid particles that it cools while completing drying before their exit through the tube (19). This gas is then sucked by the compressor (101.1) through the outlet tube (11.1). It is recycled through the treatment units (102.1) and (102.2), for example heat exchangers and / or condensers, through the tubes (8.2) and (8.3) in the annular sections (E) and (D). .
• the solid particles may be catalysts that catalyze the chemical transformation of the fluid that passes through the fluidized bed.
• the fluid is progressively transformed. It is in contact during its first passage in the reactor with a used catalyst which can be regenerated and recycled by suitable devices, and during its last passage with a fresh or regenerated catalyst and the treatment units of (102.1) to ( 102.5) can also be used to evacuate an undesirable component, for example by absorption or condensation.
• FIG. 8 shows the diagram of the schematic longitudinal section of a reactor similar to that of FIG. 1, but whose axis of rotation of the fluidized bed is vertical or strongly inclined and whose central chimney (7) ends at a certain distance above the lower side (4.2).
• the bottom of the central chimney can be closed, as shown in Figure 8, or opened.
• the solid particles that enter the central chimney can be removed from the bottom during stops, but during operation, vortices can cause the solid particles that accumulate in the bottom of the circular reaction chamber. .
• This configuration can be advantageous when the amount of fluid to be evacuated is not too high.
• the circular chamber (2) may also be conical to reduce this difference and / or the amount of fluid injected into the lower part of the circular reaction chamber may be increased, for example by increasing the number and / or the section of the fluid injectors and / or the pressure in the annular section (C) of the distribution chamber.
• FIG. 8 also includes, by way of illustration, the diagram of an ejector fluid supply system for recycling a fraction of this fluid without the use of a compressor.
• This scheme is useful when the fluid needs to be recycled once or twice and the use of compressors is difficult, for example because of the corrosivity of the fluid or very high temperatures, for example for the dehydrogenation of the fluid.
• FIG. 9 shows the diagram of the longitudinal section of a reactor similar to that of FIG. 1, comprising at each end of the central stack a centrifugal compressor, (108.1) and (108.2), symbolized by the propellers (109.1) and (109.2), which are driven by a common motor (110) through the drive shaft (111) which passes through the central chimney.
• the fresh fluid (112) is fed by the tube (8.1) located on the side of the outlet (19) of the solid particles, possibly passing through a processing unit (113), such as for example a moisture condenser. It is then recycled a number of times, successively by the compressors (108.1) and (108.2) through the tubes (8.2) and (8.3) and the processing unit (102), such as for example a heater, before to be evacuated.
• a processing unit such as for example a moisture condenser
• Fluid streams may be recycled in the same annular sections, for example to polymerize the catalyst particles suspended in mixtures of active fluids containing the monomer or monomers and may have compositions and / or temperatures different from one section to the next. other to obtain multimodal polymers and / or broad molecular distribution.
• Figure 10 illustrates a diagram that can be used for this type of application.
• the feed chamber and the central chimney are divided into four sections, respectively from (A) to (D) and from (A °) to (D °), by the transverse walls of (20.1) to (20.3) and (115.1) to (115.3).
• annular transverse walls of (116.1) to (116.3) can be extended by the annular transverse walls of (116.1) to (116.3) so as to also separate the circular reaction chamber into four annular sections corresponding to the four sections of the feed chamber and the central stack for better separating the fluids from one section to the other, provided that passages (117.1) to (117.3) are provided in these annular transverse walls, from (116.1) to (116.3), along the circular wall, to allow the transfer of the solid particles from one annular section to the other and from the passages (118.1) to (118.3) against the central chimney or inside thereof to allow the passage of fluid in order to equalize the pressures between the different sections of the central chimney.
• the fluids are gases, it is possible to spray fine droplets (120) of a liquid on at least a portion of the surface of the fluidized bed by one or more tubes (121) passing through the central stack.
• the fluid after being slowed down by the solid particles, the fluid must maintain a medium tangential speed sufficient to avoid significant reflux. For example it must perform an average of more than a half turn before exiting the reaction chamber in the diagrams described above which contain only one outlet opening (14) per section and where the fluid is injected more or less uniformly along the circular wall.
• the first condition can be written, for an annular slice of the reaction chamber, in an approximate manner, neglecting the effect of the presumed low pressure variations on the specific mass of the fluid:
• Ke which may be greater than 1 when the fluid which has just been injected is confined between a "wall" of solid particles and the circular wall making it possible to convert a fraction of its kinetic energy and / or its pressure into kinetic momentum, is a variable coefficient of transfer efficiency of the Tangential kinetic moment of the fluid towards the particles, m, Vi, and Vt are respectively the averages of the specific mass, the injection and tangential velocity of the fluid,
• Ei is the sum of the thicknesses (widths) of the outlet openings of the injectors passing through the annular slice
• Cc and M are the average concentration and the specific mass of the solid particles
• E and R are the average thickness (width) and the radius of the reaction chamber
• Kf is a variable coefficient of friction representing the% of kinetic moment that must receiving the solid particles per unit time to reach and maintain the average rotation speed Vp.
• Equation (2) allows to write:
• the estimated average tangential velocity of the solid particles and that of the gas varies from about 4.6 to 4 m / s and from 5.5 to 5 m / s respectively and the coefficient X and the product of Cc * Kf / Ke vary only from 0.9 to 1 and from 7% to 8% / s, when the concentration of the solid particles is progressively increased by 10 to 30%, confirming that the efficiency of the kinetic momentum transfer from the fluid to the solid particles improves when the concentration of the solid particles, and thus the "walls" of solid particles channeling the fluid, increases.
• the losses of solid particles from the central stack appear and increase rapidly when the average concentration of solid particles approaches 28% and the coefficient X is close to 1.
• the fluid rotates about 5 times faster by completing on average more than 2 revolutions around the central chimney before entering and the centrifugal force is about 25 times higher.
• This therefore makes it possible to increase the concentration of the solid particles and / or to reduce the injection speed of the fluid and / or to increase the diameter of the reaction chamber while keeping a very good separation of the fluid and the solid particles.
• the performance can also be improved if the coefficient of friction, Kf, is smaller and if the kinetic moment transfer efficiency coefficient, Ke, is greater, which can be obtained by increasing the number of injectors of the fluid. and improving the profile of the injectors and the circular chamber.
• the fluid is a slightly lighter fluid than the solid particles, its number of revolutions, rotational speed, and centrifugal force increase further, which allows for an acceptable separation of fluid and solid particles, even if the critical velocity Vc is much smaller because of the small difference in specific masses.
• the present invention relates to a rotating fluidized bed device in a succession of cylindrical chambers for the catalytic polymerization, drying, impregnation, or other treatments of solid particles, suspended in the fluidized rotating beds, passing from one chamber to another, by a fluid or mixture of fluids, or for cracking, dehydrogenation or other catalytic transformations of a fluid or mixture of fluids, passing through the rotating fluidized beds, composed of solid catalytic particles passing from one cylindrical chamber to another.
• the invention relates to a device with a rotating fluidized bed and a process for the catalytic polymerization, drying or other treatments of solid particles or for the catalytic transformation of fluids, in which a cylindrical reactor, in which fluids are injected tangentially to its cylindrical wall is divided into a succession of cylindrical chambers by hollow discs, which are fixed to its cylindrical wall, which have central openings through which the fluids circulating by turning inside the cylindrical chambers are sucked up, which have lateral openings through which these fluids are discharged through the cylindrical wall of the reactor and which have passages for the transfer of solid particles suspended in the rotating fluidized bed from one chamber to another through these disks.
• a cylindrical reactor is divided into a succession of cylindrical chambers by a succession of flat cylinders or hollow disks fixed against its side wall.
• These hollow discs include openings in their center to suck the fluid through each chamber by rotating quickly, and openings in their side wall to evacuate outside the reactor.
• These hollow discs are traversed by appropriately profiled passages to allow the solid particles in suspension in the fluid, rotating rapidly, to pass from one cylindrical chamber to another.
• the present invention thus relates to a device with rotating fluidized beds comprising: a cylindrical reactor; a device for feeding solid particles into said reactor and a device for discharging said solid particles from said reactor for discharging said solid particles suspended in said rotary fluidized beds; a device for supplying gaseous or liquid fluids, designed to inject said fluid or mixture of fluids into said rotary fluidized beds, regularly distributed along the cylindrical wall of said reactor, in approximately directions; tangential to said cylindrical wall and approximately perpendicular to the axis of symmetry of said reactor, for rotating said rotating fluidized beds at a speed producing a centrifugal force pushing said solid particles towards said cylindrical wall; a device for discharging said fluid or fluid mixture, centrally, along the axis of symmetry of said reactor; characterized in that it comprises hollow discs, perpendicular to the axis of symmetry of said reactor and fixed against the cylindrical wall of said reactor, dividing said reactor into a succession of cylindrical chambers interconnected by passages arranged through said hollow discs,
• the fluid or mixture of fluids is injected tangentially along the cylindrical wall of the reactor, generally in thin films, and, while rotating, passes radially through the reactor, from its side wall towards its center, where it is evacuated through the central openings of the hollow discs.
• the injection speed of the fluid and its flow rate are sufficient to rotate the solid particles in suspension in a rotating fluidized bed at a rotation speed producing a centrifugal force away from the central openings of the hollow discs through which the fluid is discharged and allowing to transfer them from one cylindrical chamber to another, through the passages in the hollow discs, despite the slight slight difference in pressure between these cylindrical chambers.
• the fluid is fed by one or distributors outside the reactor, in order to distribute it properly to the injectors located in the different chambers.
• cylindrical It is then evacuated, through the hollow discs, by one or more fans or compressors, which suck it through one or more collectors, outside the reactor and connected together, in order to regulate the pressures inside the fans.
• different cylindrical chambers The fluid can then be recycled, after a suitable treatment, for example cooled or heated, by the same distributors or other distributors, in the same or subsequent cylindrical chambers. It can be recycled several times in the same cylindrical chambers or in successive cylindrical chambers.
• the solid particles are generally introduced at one end of the reactor and then transferred from one cylindrical chamber to the other, thanks to their rotational speed and to the profile of the passes through the hollow discs. They are usually discharged at the opposite end of the reactor.
• a device for recycling solid particles may be provided outside the reactor.
• the present invention may comprise, for improving the efficiency of the energy transfer between the fluid and the solid particles, adequately shaped baffles and disposed near the injectors of the fluid, to allow mixing of the fluid with a limited amount of particulate. the solids and in order to channel the fluid to prevent or reduce its expansion in the reactor before it has transferred a significant amount of its kinetic energy to these solid particles.
• This device makes it possible to use fluids that are much lighter than solid particles and to inject it at high speed into a large reactor without losing much of its kinetic energy because of its expansion in the reactor.
• Such a device is described in the application for a Belgian patent in the name of the same inventor and filed on the same day as the present application.
• the present invention may comprise sets of helical coils or transverse fins, inclined or helically wound and secured along the cylindrical wall of the cylindrical chambers, to utilize a portion of the rotational kinetic energy of the solid particles to make them climb along this wall, to reduce the difference in thickness between the top and bottom of the fluidized bed.
• This device makes it possible to increase the height of the cylindrical chambers without having to increase the thickness of the fluidified bed at its base. Such a device is described in application No. 2004/0186 of a Belgian patent, filed on April 14, 2004 in the name of the same inventor.
• the reactor can be horizontal.
• the rate of injection of the fluid into the reactor and its flow rate must be sufficient to rotate the fluidized bed at a rotation speed producing sufficient centrifugal force so that its thickness in the upper part of the reactor is close to its thickness.
• in the lower part of the reactor and the openings normally provided in the center of the hollow discs may be slightly offset downwards in order to better center them with respect to the approximately cylindrical surface of the fluidized bed.
• This method makes it possible to increase the speed difference between the solid particles and the fluid without reducing the density of the fluidized bed by virtue of the centrifugal force and thus to improve the contact and the heat transfer between them. It also makes it possible to significantly increase the volume of fluid passing through the fluidized bed and thus significantly reduce the residence time of the fluid in the fluidized bed.
• the invention relates to a device, characterized in that said feeder of said fluid or mixture of fluids is equipped with lateral baffles, arranged near the fluid injectors so as to allow mixing of the fluid.
• said fluid or mixture of fluids with a part of said solid particles rotating in said cylindrical chambers and accelerate them in the spaces delimited by said lateral deflectors, suitably shaped to allow said fluid to transfer a large part of its energy to said solid particles before leaving said delimited spaces and said solid particles to transfer the momentum acquired to other so-called solid particles rotating in said cylindrical chambers after their exit from said defined spaces.
• the invention relates to a device characterized in that said central openings of said hollow discs are equipped with one or more central deflectors, which longitudinally pass through said cylindrical chambers, and which have curvatures delimiting one or more central access slots through which said fluid or mixture of fluids is sucked toward said central openings, said bends and said access slots being arranged to reduce the probability that said solid particles can penetrate in said openings of said hollow discs.
• the device according to the present invention is characterized in that at least one of said hollow disks contains one or more partition walls for separating said fluid or mixture of fluids which enters said hollow disk and which comes from said cylindrical chambers. driques separated by this said hollow disk.
• the device according to the present invention is characterized in that at least one of said hollow disc allows the passage of an injector capable of spraying fine droplets of a secondary fluid on the surface of at least one said fluidized rotating bed of at least one of said cylindrical chambers, at least one of said other fluids being gaseous.
• the device according to the present invention is characterized in that said reactor comprises an outlet in the side wall of each said cylindrical chamber to allow complete evacuation of said solid particles contained in each said cylindrical chamber.
• the device according to the present invention is characterized in that it comprises a device for recycling said fluid or mixture of fluids, after appropriate treatment, for recycling in said cylindrical chambers, by said device fluid supply, said fluid or mixture of fluids evacuated by said device for discharging said fluid or mixture of fluids.
• the device according to the present invention is characterized in that said device for feeding said solid particles feeds said cylindrical chamber located at one end of said reactor and said evacuation device of said solid particles evacuate said solid particles from said cylindrical chamber located at the other end of said reactor.
• the device according to the present invention is characterized in that said device for feeding said solid particles in said chamber cylindrical is slaved to a device for detecting the surface of said rotating fluidized bed of said chamber, said slaving to maintain said surface at the desired distance from the cylindrical wall of said chamber.
• the device according to the present invention is characterized in that said device for discharging said solid particles from a said cylindrical chamber is slaved to a device for detecting the surface of said rotary fluidized bed of said chamber, said servo to maintain said surface at the desired distance from the cylindrical wall of said chamber.
• the device according to the present invention is characterized in that it comprises said passages which are profiled in order to facilitate the transfer of said solid particles from one said cylindrical chamber to the other towards one end.
• said reactor and which are located at the desired distance from said central openings of said hollow discs, in order to stabilize said surfaces of said rotating fluidized beds, the flow rate of the particles transferred to said end increasing or decreasing according to said passages are more or less immersed in said rotating fluidized beds.
• the device according to the present invention is characterized in that it comprises said passages which are located along said cylindrical wall of said reactor and which are profiled in order to facilitate the transfer of said solid particles. a said cylindrical chamber to the other in a direction that allows to fill or empty gradually said solid particles all of said cylindrical chambers of said reactor.
• the device according to the present invention is characterized in that it comprises said secondary passages, which are located along said cylindrical wall of said reactor and which are profiled to facilitate the transfer of said solid particles of a said cylindrical chamber to the other in the opposite direction to that of said other passages in order to ensure a preferential reflux of said heavier solid particles.
• the device according to the present invention is characterized in that said feeder of said fluid or mixture of fluids in at least one of said cylindrical chambers is slaved to a detector of the surface of said bed fluidized rotary of said cylindrical chamber, said servo to maintain said surface at the desired distance from said side wall of said chamber.
• the device according to the present invention is characterized in that said feeder of said fluid or mixture of fluids comprises long longitudinal slits passing through said side wall, parallel to the axis of symmetry of the said reactor, said long longitudinal slots being connected to at least one fluid distributor external to said reactor and for regulating the inlet velocities of said fluid or mixture of fluids injected into said reactor by said long slots.
• the present device is characterized in that the said long longitudinal slots pass through the said side wall from one end to the other of the said reactor, making it possible to separate the said cylindrical wall of the said reactor from minus two cylin- der fractions.
• the device according to the present invention is characterized in that said device for discharging said fluid or mixture of fluids comprises transverse slots, perpendicular to the axis of symmetry of said reactor and passing through its said cylindrical wall along said lateral openings of said hollow discs, said so-called transverse slots being connected to at least one fluid collector external to said reactor and making it possible to regulate the outlet pressure of said fluid or mixture of fluids discharged from said reactor by said transverse slits.
• the device according to the present invention is characterized in that it comprises two said distributors and two said collectors which are tubes along said cylindrical wall of said reactor, these four tubes forming with said reactor a compact assembly that can be contained in a rectangular parallelepiped.
• the device according to the present invention is characterized in that it forms a compact, removable and transportable assembly.
• the present device is also characterized in that said reactor is horizontal. According to a preferred embodiment the present device is characterized in that said reactor is tilting to increase or decrease the transfer of said solid particles through said passages to said evacuation device without the volume of said fluidized bed varies significantly. According to another particularly preferred embodiment, the present device is characterized in that the said central access slot or slots are arranged in the upper half of the said reactor to reduce the probability of entry of the said solid particles into the said hollow disks during stops.
• the device according to the present invention is characterized in that said reactor is vertical and that said hollow discs each comprise only one said central opening located on their lower wall.
• the device according to the present invention is characterized in that said reactor is vertical and that said central openings of the upper walls of said hollow discs are extended by vertical tubes to reduce the probability that said particles solids rotating in said cylindrical chambers fall into said central openings during stops.
• the device according to the present invention is characterized in that the cylindrical walls of said cylindrical chambers are equipped with transverse fins or helical spirals allowing said solid particles to use part of their rotational kinetic energy for mounting therealong, to reduce the pressure and thickness differences of said rotatable fluidized beds between the top and bottom of said cylindrical chambers.
• the device according to the present invention is characterized in that it comprises a transfer column or a tube outside said reactor for recycling said solid particles discharged from said cylindrical chamber at one end of the said reactor in said cylindrical chamber located at the other end of said reactor.
• the device according to the present invention is characterized in that it comprises at least two sets of said successions of said chambers cylindrical and at least one said passage for transferring said solid particles from one said assembly to the other said together, and in that said devices for supplying and discharging said fluid or mixture of fluids allow supplying said fluid or mixture of fluids discharged from one of said sets into the other said set.
• the device according to the present invention is characterized in that it comprises at least two sets of said successions of said cylindrical chambers and at least one said passage for transferring said solid particles of a said set at the other said together, and in that said devices for supplying and discharging said fluid or mixture of fluids can separately evacuate said fluid or mixture of fluids of each of said sets and the recycle in the same said set.
• the present invention for improving the efficiency of momentum transfer and kinetic energy transfer between a fluid jet and solid particles suspended in a rotating fluidized bed, also comprises deflectors, within the rotary fluidized bed, suitably profiled and arranged near the fluid injectors, to allow mixing of the injected fluid with a limited amount of solid particles, while channeling it, to prevent or reduce its expansion in the reactor before he transferred a significant amount of his kinetic energy to these solid particles.
• the device according to the invention is provided with a device for supplying one or more fluids, which comprises a device for injecting fluid into the interior of said rotating fluidized bed, which device for injecting fluid comprises at least one deflector delimiting inside said rotated fluidized bed a space around one or more jets of said fluid directed in the direction of rotation of said rotating fluidized bed, coming from one or more injectors said fluid, said deflector being arranged to delimit between said injector (s) and said deflector, a passage or corridor to access a flow of said solid particles suspended in said rotating fluidized bed, from the upstream of said injector, to enter the said space to mix with the said fluid jets or said fluid, said space being long enough to allow this or said fluid jets to yield a pa of their kinetic energy to said solid particles before reaching the exit of this space.
• the present invention therefore also relates to a device for injecting a fluid or mixture of fluids, liquid or gaseous, inside a rotating fluidized bed to increase the amount of movement and energy that the fluid can transfer to solid particles rotating in a rotating fluidized bed in order to increase the speed of rotation.
• This device makes it possible to use fluids that are much lighter than solid particles and to inject it at high speed into the reactor without losing a large part of its kinetic energy because of its expansion in the reactor.
• the invention relates to a device for injecting fluids into a rotating fluidized bed where the fluid jets are oriented in the direction of rotation of the fluidized bed and surrounded by at least one deflector delimiting around these jets a generally convergent space and then diverging and upstream of these jets passages through which the particles in suspension in the rotating fluidized bed can penetrate in order to mix with the jets of fluids which transfer to them part of their kinetic energy before leaving this space.
• the present invention provides a device for injecting fluid with the interior of a rotating fluidized bed for improving the efficiency of the transfer of energy and momentum of said fluid to the solid particles suspended in said rotary fluidized bed, characterized in that it comprises at least a baffle delimiting inside the said rotating fluidized bed a space around one or more jets of said fluid directed in the direction of rotation of said rotary fluidized bed, coming from one or more injectors of said fluid, said deflector being arranged so as to delimit between said injector (s) and said deflector, a passage or corridor of access to a flow of said solid particles suspended in said rotating fluidized bed, coming from the upstream of said injector, to enter the said space to mix with the said fluid jets or said fluid, said space being long enough to allow this or said fluid jets to yield a substantial portion of their kinetic energy to said solid particles before reaching the exit of this said space.
• the present fluid injection device inside a rotating fluidized bed is characterized in that the said space defined by the said deflector and surrounding the said fluid jet or jets is first converge then diverge.
• the present fluid injection device inside a rotating fluidized bed is characterized in that said space defined by said deflector and surrounding said fluid jet (s) is constant section.
• the fluid injection device is characterized in that the section of said fluid injector (s) is elongated in order to inject said fluid in the form of one or more thin films along the cylindrical wall of the reactor containing the said fluidized rotating bed and that the said deflector in the form of a fin delimiting with said cylindrical wall of said reactor said space, through which passes or said films not thick of said fluid.
• the fluid injection device is characterized in that said space is at least twice as narrow as the average thickness of said rotating fluidized bed.
• the fluid injection device is characterized in that it comprises rings or fraction of transverse rings fixed along the cylindrical wall of the reactor containing said fluidized bed and delimiting with said deflector and said cylindrical wall of said reactor said space through which pass said fluid jets.
• the fluid injection device is characterized in that said ring fractions are transverse fins inclined with respect to the central axis of said reactor in order to cause the said solid particles to be suspended in suspension. said fluidified rotating bed along said cylindrical wall of said reactor.
• the fluid injection device is characterized in that said rings or ring fractions are helical turns oriented so as to raise said solid particles in suspension in said rotary fluidized bed. along said cylindrical wall of said reactor.
• the fluid injection device according to the present invention is characterized in that the section of said passage or access passage is greater than the section of said injector or injectors.
• the fluid injection device according to the present invention vention is characterized in that the section of said output of said converging space then diverging is equal to or greater than the sum of the sections of said injectors and said passage or access corridor.
• the fluid injection device is characterized in that said fluid is a gas of much lower density than the density of said solid particles and that it is injected into speeds at least 3 times higher than the average rotational speed of said solid particles suspended in said rotating fluidized bed.
• the fluid injection device according to the present invention is characterized in that the length of said space is sufficiently short for said fluid to still have a speed substantially greater than the speed of said solid particles. leaving the said space.
• the present invention can also be applied to a horizontal reactor.
• the rate of injection of the fluid into the reactor, its flow rate and the efficiency of the transfer of its kinetic energy must be sufficient to give a rotational speed to the fluidized bed producing sufficient centrifugal force to hold it against the cylindrical wall from the top of the reactor.
• FIGS 11 to 22 illustrate embodiments of a rotating fluidized bed device according to the invention wherein the circular reaction chamber is divided into a succession of cylindrical chambers.
• FIG. 11 shows a schematic view of a section of a vertical cylindrical reactor whose section of its cylindrical side wall (201) is seen on each side of its cylindrical axis of symmetry (202).
• a series of hollow discs with hollow sections (203) divide the reactor into a succession of chambers or cylindrical zones Z1 to Z3.
• the fluid (204) is supplied by the distributor (205) in sets of tubes (206) distributed around the reactor and connected to sets of injectors (207) distributed inside the reactor and designed to inject the fluid , generally in thin films, horizontally and tangentially to the reactor wall, that is to say perpendicular to the plane of the figure. While rotating, the fluid passes through the fluidized bed which contains solid particles in suspension, symbolized by the black dots.
• the fluid (210) penetrates into the central openings of the hollow discs (203), which can be surmounted by tubes (211) to prevent the solid particles do not penetrate during stops and that can be widened (212) around their central openings to facilitate the entry of the fluid.
• the fluid (213) is then evacuated through the openings (214) of the side edges of the hollow discs which can be widened (215) around these openings (214) to facilitate the outlet of the fluid by the tube assemblies (216).
• the injection speed of the fluid is influenced by the hydrostatic pressure generated by the weight of the fluidized bed in each zone.
• the slots (207) through which the fluid is injected can be adequately profiled, as symbolized by their trapezoidal shape, and they can be equipped with obstacles distributed appropriately to reduce the injection speed in their upper part.
• Control valves (222) can also be used to adjust the velocity and the proportion of the fluid (223) injected at the different levels of the cylindrical chambers.
• a control valve (224) can also adjust the fluid output flow (220).
• the introduction of the solid particles (225) can be done in the bottom of the reactor by the tube (226) by suitable means, such as gravity, a helical screw or a jet of fluid.
• the reactor being divided by the hollow discs into several cylindrical chambers, from Z1 to Z3, they rise from one chamber to the next, through the passages (227) which are arranged through the hollow discs. They are removed from the last cylindrical chamber, Z3, at the top of the reactor, at (229), by the tube (230) by appropriate means.
• Other outlets (230.1) may be provided, for example in the bottom of each chamber, to be able to empty the reactor quickly.
• the amount of particles transferred depends on the rotational speed of these particles, which must be sufficient to overcome the hydrostatic pressure of the fluidized bed above the passage.
• a control valve 222
• the energy injected into the top of this chamber is increased and thus the rotation speed solid particles and thus their transfer to the upper zone.
• these valves By slaving these valves to level detectors on the surface of the fluidized beds of each chamber, these surfaces can be stabilized between the passages and the central entrance of the hollow disks. This makes it possible to locate these passages against the side wall of the reactor, where the concentration of the particles is highest and thus to reduce the amount of fluid entrained with these solid particles.
• the amount of solid particles transferred from one zone to another may also vary depending on whether the passages are more or less immersed in the fluidized bed of the lower cylindrical chamber, which makes it possible to stabilize the surface of the fluidized bed at the top of each cylindrical chamber along these passages.
• the fluidized bed may be thicker or thinner as a function of the distance of these passages from the lateral edge of the reactor.
• the reactor can be emptied by lateral outlets at the bottom of each zone and its initial filling can be done from below, by closing the supply of fluid through the tubes (206) of the upper cylindrical chambers that are not filled during the filling of the reactor. a lower cylindrical chamber, to prevent most of the fluid from passing through the empty chambers. It can also be done through the tubes of supply of the recycled fluid, if the dimension and the nature solid particles allow it or from above if the orientation of at least one hollow disk passage allows it.
• the thin film of fluid emerging from the injectors has a tendency to expand very rapidly and therefore to slow down before it has been able to transfer enough rotational kinetic energy to the solid particles.
• properly shaped side baffles may be attached more or less parallel to the reactor sidewall, near the outlets of the injectors, to mix a small volume of solid particles with the fluid injected into the spaces or corridors between these side baffles and the reactor wall.
• These lateral deflectors prevent the fluid from expanding, and therefore slowing down, before it has transferred a sufficient portion of its kinetic energy to the solid particles, inside these spaces or corridors, which must have a profile and a length adapted to the objectives.
• Figure 12 is a cross section of a reactor for viewing a fluid injection device. It shows the section (301) of the cylindrical wall of a cylindrical reactor of radius (233), the sections (302) of width (303) of fluid injectors (304), penetrating tangentially in the reactor, and the section (305) of lateral deflectors, arranged longitudinally (perpendicular to the plane of the figure) at a small distance from the cylindrical wall of the reactor, opposite the injectors, in order to channel the fluid jets into the spaces or corridors (306) , generally convergent then divergent, located between the baffles and the cylindrical wall of the reactor. It also shows the circular section of the surface of the fluidized bed of radius (235). The solid particles are schematized by the small arrows (312), indicating their direction of movement.
• These lateral deflectors define with the injectors passages or corridors width access (307), whereby flows (308) of solid particles suspended in the rotating fluidized bed can enter these spaces (306) and mix with the jets fluids (304). Concentrated flows of solid particles, symbolized by the arrows (308), penetrate into these spaces or corridors, generally converging and then diverging, by passages or corridors of access, width (307), located between the wall of the injectors (302) and the side baffles (305) at a rate which is about the average rotational speed of the solid particles in the reactor.
• the convergence or divergence limited by the deflectors in the first part of these spaces (306) prevents or limits the expansion of the fluid jets whose pressure can decrease to maintain a good part of their speed while they accelerate the flows ( 308) of solid particles.
• the fluid flows (309) then slow down in the divergent portion of these spaces or corridors (306) and their pressure can rise to reach the reactor pressure. Thanks to their inertia the solid particles are less slowed down and can have a tangential exit velocity close to and even greater than that of the fluids which will have given them a large part of their kinetic energy.
• the pressure injection and therefore their energy must increase to allow fluids to escape through the outlet (311), despite the strong slowdown caused by solid particles.
• This pressure increase is reflected in the access passages or corridors (307) and decreases the entry speed of the solid particles, whose concentration increases and the flow rate decreases, thus decreasing the amount of energy that they can absorbing, in order to find an equilibrium of the energy transfer dependent on the dimensions of these spaces (306), velocities and densities of the solid particles and fluids.
• the length of these spaces (306) must be shorter as the ratios between the width (303) or section of the injectors and the width (307) or section of the access passages are small, so that the fluids still have a speed substantially greater than that of the particles at the outlet (311).
• the amount of energy transferred to the solid particles will be greater if these section ratios are small and the length of these spaces (306) is large, the optimum depending on the operating conditions and objectives.
• This diagram also shows the section (311) of the surface of the rotating fluidized bed, the solid particles symbolized by small arrows (312) indicating their direction of movement, the section of central baffles (313) defining longitudinal slots allowing Centrally aspirating the fluids (314), for their evacuation from the reactor, the curvature (315) of these central deflectors ensuring the separation between the solid particles and the fluid before suction.
• the access tubes to the hollow discs not shown, are connected by central deflectors, perpendicular to the plane of the figure, of section (313), of curvature (315), delimiting slots by which the fluid (314) is sucked towards the central openings of the hollow discs, and to better separate the fluid particles.
• these spaces or corridors are first convergent, to reach a minimum width (310), and then divergent, to reach the output width (311). They can also have a constant width. In this case, the fluid is slowed down as the solid particles and the fluid that accompanies them accelerate. In general, the dimensions of these spaces or corridors must be established according to the operating conditions and the objectives of kinetic energy transfer.
• transverse deflectors perpendicular to the cylindrical wall of the reactor, such as rings, can divide the space delimited by the fins and the side wall of the reactor, to guide the fluid and the particles in the desired direction , generally horizontal or inclined upwards, until the fluid is mixed with the particles, as shown in Figure 13.
• Figure 13 is an axonometric projection of a portion of the side wall (301) of a reactor to better visualize the fluid injection devices.
• Injectors are shown schematically in (316), or their longitudinal section (317) with their side deflectors (319) and rings (320), serving as transverse deflectors preventing the fluid to rise along the wall of the reactor. It also shows, in dashed line, the entries of the fluid supply tubes (318) located behind the side wall of the injectors, and, hatched, the sections of the injector outlets (317), at the foreground.
• the arrows (304) and (321) respectively indicate the directions of the fluid flows and solid particles penetrating or exiting the converging and diverging spaces between the side baffles (319) and the side wall (301) of the reactor.
• the injectors are separated by rings or transverse ring fractions (320) along the side wall (301) of the reactor and the side baffles (319) are inserted between these rings, leaving an access corridor to the solid particle streams , symbolized by the black arrows (321).
• the transverse deflectors illustrated by large rings (320), may be hollow, forming a kind of circular nozzles and connected to the outside of the reactor by one or more feed tubes to distribute the fluid to a succession of injectors arranged along them, to reduce the number of tubes passing through the reactor wall, necessary for feeding the injectors, which may be desirable when the pressure in the reactor is high.
• These rings or ring fractions may be transverse fins or helical coils oriented so as to raise the solid particles along the side wall of the reactor. They can also be hollow and serve as a fluid distributor to the injectors connected thereto.
• rings or ring fractions can also be successions of helical turns, forming an upward spiral, continuous or discontinuous, at the same time.
• Figure 15 shows the section of a passage (227). It shows the section (203) of the two parallel plates forming the hollow disk and its inner space (250) through which the fluid passes radially, that is to say perpendicular to the plane of the figure, to exit the reactor.
• Solid particles are represented by black dots moving in the direction of the arrows (251). They pass through the hollow disc along the inclined walls (252) of the passage. They are extended by baffles (253) on each side of the hollow disk to facilitate the transfer of particles from bottom to top, in the direction of their rotational speed. These deflectors (253) can be extended by spirals whose section (246) is seen, in order to facilitate the ascent of the solid particles.
• Figure 16 is a transverse flow diagram of the solid particles along a half longitudinal section of a cylindrical chamber similar to that shown in Figure 4, without the side and central baffles.
• the section (201) of the reactor wall, its cylindrical axis of symmetry (202), the feed tubes (206) of the fluid (204) in the section injectors (207), the sections (246) are recognized. of the beginning of the quarter turns of helical turns along the side wall of the cylindrical chamber, located below the sections (246.1) of the end of the quarter of helical turns located in the quarter of the cylindrical chamber in the foreground of the figure.
• Another way of adjusting the level of the fluidized bed is to slave the fluid injection rate in the upper part of the chamber to a particle detector, which can be placed along the bottom wall of the hollow disk and which , depending on the position of the surface of the fluidized bed, increases or decreases this flow rate and therefore the rotational speed of the solid particles and therefore the amount of solid particles transferred through the passage (227s).
• the pressure difference between the top and the bottom of the cylindrical chamber can cause differences in injection speeds of the fluid as a function of the height of their injection. These differences generate differences in rotational speeds of the solid particles.
• the difference in pressure between the two faces of the hollow discs and more particularly between the inlet and the outlet of the passages through these hollow discs and the friction slow down the solid particles which are transferred from one chamber to the other and therefore slow down the speed of rotation of the solid particles in the bottom of the next cylindrical chamber.
• the lower rotational speed of the solid particles and therefore of the centrifugal force in the bottom of the cylindrical chambers causes both a slight decrease in the pressure along the side wall and a slight increase in the thickness of the fluidized bed.
• the solid particles are slowed down by the friction and the increase of their potential energy while climbing along the upper surface of the helical turns, which causes the same type of internal circulation between the sets of helical turns.
• These successive slowdowns in the speed of rotation of the solid particles and their internal circulation increase the amount of energy that the fluid must transfer to the particles, requiring an efficient transfer of momentum and a very high fluid flow, which is well suited to this process. .
• Approximately the internal circulation can be estimated by dividing the fluidized bed into rings, which are assumed to have mean rotational velocities, and determining the pressure and thickness deviations between these rings to deduce the importance of this circulation, and then apply conservation. the amount of motion to determine by successive approximations the average equilibrium rotation speed of these rings.
• the fluid can yield to the solid particles almost all of its available kinetic energy.
• the fluid can still yield to the solid particles more than 80% of its kinetic energy with much lower velocity ratios vf / vp.
• the optimum, more precise dimensions, depending on the objectives, can be determined, taking into account all the parameters, by numerical simulation and by experiment in pilot units.
• the injection of the fluid all along an injection slot being at the same height, from a distributor which standardizes the injection pressure, its injection speed is approximately uniform. On the other hand it can vary from one slot to another, if these slots are not arranged at the same height in the reactor. It is lower for slots in the bottom of the reactor. If the difference is too large and it is necessary to place injection slots in the bottom of the reactor, it may be necessary to have separate distributors, to inject the fluid at different pressures.
• the energy transferred to the particles by the fluid passing through the fluidized bed is equal to the energy lost by the fluidized bed, due to friction and turbulence, and to the energy lost by the particles during their transfer through the passages in the hollow discs due to the friction and the change of orientation of the particle velocity during these transfers or, for the first zone, the energy to be acquired by the particles injected into this zone, dependent their injection speed.
• FIG. 20 schematizes the half-section of a zone of a vertical reactor, in order to visualize the internal circulation and its influence on the surface of the fluidized bed.
• R1 ', R1 and R1 "; v', v and v" are defined as being respectively the radius of the surface of the fluidized bed and the average speed of rotation of the particles, perpendicular to the plane of the figure, in the n-1, n and n + 1 slices.
• the injection of the fluid is then at reduced speed in the middle part of the zone.
• the speed of rotation of the solid particles gradually slows down there, v '> v> v ", and the internal circulation, Fi, slows down there and can even be reversed if this part is sufficiently high.
• the increase or decrease of the internal circulation energy from one slice to the other is equal to the energy received by the dynamic slope and pressure deviation minus the energy loss due to turbulence and friction. The latter is
• the internal circulation, Fi whose sum is zero, is added to the circulation, Fp, particles passing from one area to another through the passages (227) through the hollow discs (203). They cause rotational energy transfers of the particles between the different slices, Et 'and Et ", thus reducing the differences between their rotational speeds.
• the fluid injection speeds vf ", vf and vf, respectively in the n + 1, n and n-1 slices depend on the pressure difference between the distributor and the inside edge of the reactor, which varies by one slice. To the other, that is to say, as a first approximation, for small pressure variations, the square of the injection speed of the fluid in the slice n is: vP ⁇ vf 2 + 2g.X.dh-2X.E.
• the pressure difference, dPp, through this passage is approximately: dPp ⁇ Dp. [(H + Ed) + Lp. (V 2 -v ' 2 ) / Rg], where v is the average speed of rotation of the particles at the base of the zone considered.
• the equilibrium equation of energy across the passages is: Dp. (Kp 2 .vpe 2 -vps 2 ) / 2 ⁇ dPp.g, which allows to estimate vps if the lower zone is similar to the zone considered.
• the device of the present invention can be applied to industrial processes of catalytic polymerization, drying, impregnation, coating, roasting or other treatments of solid particles suspended in a fluidized bed or cracked, dehydrated - Generation or other catalytic transformations of fluids or fluid mixtures passing through a fluidized bed.
• the present invention relates to a method of catalytic polymerization, drying or other treatments of solid particles suspended in a rotating fluidized bed or catalytic transformation of fluids passing through said rotary fluidized bed characterized in that it comprises the steps of injecting one or more fluids, in successive layers, into a circular reaction chamber, and evacuating them centrally through a central chimney passing through or into said chamber circular, according to the present invention, a flow and injection pressure causing said solid particles at a mean speed of rotation generating a centrifugal force at least three times greater than the force of gravity.
• the present invention relates to a process for the catalytic polymerization, drying or other treatment of solid particles suspended in a rotating fluidized bed or catalytic conversion of fluids passing through said rotary fluidized bed, characterized in that that it includes the step of recycling the said fluid or fluids.
• the present invention relates to a method of catalytic polymerization, drying or other treatments of solid particles suspended in a rotating fluidized bed or catalytic conversion of fluids passing through said rotating fluidized bed, characterized in that it comprises the step of recycling said solid particles.
• the present invention also relates to a process for catalytic polymerization, impregnation, coating or other treatments of solid particles in suspension in a rotating fluidized bed, characterized in that it comprises the steps of spraying a liquid into fine droplets on said solid particles and chemically reacting said liquid impregnating or surrounding said particles with said one or more gaseous fluids passing through said rotating fluidized bed.
• the present invention relates to a process for the catalytic polymerization, drying or other treatments of solid particles suspended in rotating fluidized beds or catalytic conversion of fluids passing through rotating fluidized beds, characterized in that it comprises the steps of injecting into a horizontal cylindrical reactor, preferably comprising a succession of connected cylindrical chambers according to the present invention, a fluid or mixture of fluids at a rate and a flow rate giving said solid particles a higher average speed of rotation at the square root of the product of the reactor diameter and g which is the acceleration due to gravity.
• the present invention also relates to a process for the catalytic polymerization, drying or other treatments of solid particles suspended in rotating fluidized beds or of catalytic conversion of fluids passing through rotating fluidized beds, characterized in that it comprises the steps of injecting into a vertical cylindrical reactor, preferably comprising a succession of connected cylindrical chambers according to the present invention, a fluid or mixture of fluids at a rate and flow rate generating in said bed rotary fluidified a centrifugal force greater than gravity, said solid particles being transferred from one said cylindrical chamber to the other downward of said reactor.
• the method of catalytic polymerization, drying or other treatments of solid particles suspended in rotating fluidized beds or of catalytic transformation of fluids passing through rotating fluidized beds comprises the steps which comprises injecting into a vertical cylindrical reactor, preferably comprising a succession of connected cylindrical chambers according to the present invention, a fluid or mixture of fluids at a speed and a flow rate giving said solid particles an average rotational speed greater than the speed they can acquire by falling from the top to the base of said cylindrical chambers and allowing them to pass from said lower cylindrical chamber to said upper cylindrical chamber by at least one passage in said hollow disk separating them and oriented in the sense of raising said ground particles ideas.
• the present invention also relates to a process for the catalytic polymerization of solid particles suspended in rotating fluidized beds or of catalytic transformation of fluids flowing through rotating fluidized beds, characterized in that it comprises the steps of injecting into a tube or a transfer column, according to the invention, a fluid regenerating the catalysts contained in said solid particles recycled in said reactor.
• said method for the catalytic polymerization of solid particles suspended in rotating fluidized beds or of catalytic transformation of fluids passing through rotating fluidized beds is characterized in that it comprises the steps of injecting into a tube or a transfer column according to the invention, a fluid purging said solid particles recycled in said reactor undesirable fluids that are driven by said solid particles.
• the invention provides a process for the catalytic polymerization of solid particles suspended in rotating fluidized beds, characterized in that it comprises the steps of recycling in at least two sets of successions of cylindrical chambers according to the invention, said fluids or mixture of fluids, separately evacuated from said sets, containing active fluids of different compositions from one set to another, to produce bi or multimodal polymers.
• the invention provides a process for catalytic polymerization of solid particles suspended in rotating fluidized beds, characterized in that it comprises the steps of spraying fine droplets of a comonomer on the surface said rotating fluidized bed of at least one said cylindrical chamber by an injector according to the invention.
• the invention relates to a polymer process catalytic conversion of solid particles suspended in rotary fluidized beds, characterized in that it comprises the steps of spraying on the surface of said fluidized bed of at least one said cylindrical chamber by an injector according to the invention, a liquid for cooling said solid particles.
• the present invention also includes the use of a device described in the present invention in a polymerization process.
• the present invention relates to the use of a device described in the present invention in a process for the polymerization of solid particles suspended in a rotating fluidized bed.
• the present invention relates to the use of a device described in the present invention in a polymerization process, characterized in that at least one of said fluids contains alpha olefins.
• the present invention may also include the use of a device described in the present invention in a process for the catalytic conversion of a fluid or fluid mixture passing through a rotating fluidized bed whose solid particles are catalysts.
• the present invention relates to the use of a device described in the present invention in a catalytic conversion process, characterized in that said fluid or mixture of fluids contains olefins, for example light olefins. and that said catalytic conversion involves changing the molecular weight distribution of said olefins, for example, light olefins.
• the present invention relates to the use of a device described in the present invention in a catalytic conversion process, characterized in that said fluid or mixture of fluids contains ethylbenzene and that the This catalytic transformation involves its dehydrogenation to turn it into styrene.
• the present invention relates to the use of a device described in the present invention in a catalytic conversion process, characterized in that said solid particles contain components that can react with hydrogen from said dehydrogenation, to reduce its concentration in said fluid or fluid mixture, said components being regenerable outside of said circular reaction chamber.
• the present invention also relates to the use of a device described in the present invention in a method for drying or extracting volatile components of said solid particles.
• the invention relates to the use of the device described in the present invention, is particularly characterized in that at least one of said hollow disc allows the passage of an injector capable of spraying fine droplets a secondary fluid on the surface of at least one said rotating fluidized bed of at least one of said cylindrical chambers, at least one of said other fluids being gaseous in a process for impregnating said solid particles with said fluid secondary.
• the present invention also provides the use of a device described in the present invention in a process for impregnating or coating said solid particles.
• the present invention relates to the use of a device described in the present invention in a drying, extraction, impregnation or coating process, characterized in that the said solid particles are grains, powder or other fragments of agricultural origin.
• a device according to the present invention can therefore adapt to different schemes, according to different methods.
• Some examples of methods are illustrated in which a device according to the invention can be applied.
• these different methods can be illustrated by numerical examples.
• the mathematical formulas mentioned in these examples relate to the aforementioned equations.
• the rotational speeds of the particles depending on a set of factors such as turbulence and viscosity of the fluidized bed, which depend on the nature of the solid particles and the aerodynamics inside the cylindrical chambers, the examples which are given for information only.
• the cylindrical reaction chamber illustrated in FIG. 8 may have, for information only, 1 m in diameter, 4.5 m in length and 0.23 m in thickness (width), which gives it a volume of approximately 2.5 m 3 .
• the fluid (100) consisting of preheated cracking gasolines at a high temperature, a specific gravity, at the injection temperature and pressure, of about 5 kg / m 3 , is injected at high speed.
• the catalyst powder which is fed by the tube (16) is driven by the fluid at an average rotation speed, Vp, of about 13 m / s, giving a centrifugal force of 35 times the gravity, generating a pressure on the cylindrical wall of about 30 000 Pa and allowing the fluid to pass through the fluidized bed at a speed of more than 2 m / s .
• the catalyst powder is discharged through the tube (19) and can be easily recycled after regeneration, with a cycle time ranging from a few minutes to many hours.
• this air (11.2) is sucked by the compressor or centrifugal fan (108.2) through the pipe (10.2) and recycled into the reactor via the pipe (8.3) after having been reheated by the heater ( 102). After being recycled again a few times, this moisture-laden and grain-cooled air, which is fed through the pipe (16) and has been reheated, is discharged at (114).
• the pressure in the reactor is lower than the atmospheric pressure, which is favorable for drying and mechanical means can easily transfer the dried grains for storage at atmospheric pressure.
• the air can be injected into the drying chamber at the same rate of 23 m 3 / s of the above example, or about 100 tons per hour. If it is recycled 5 to 10 times, this gives a quantity of fresh air from
• the quantity of grains in the drying chamber can be about 500 kg, which gives an average residence time of 90 seconds for the drying of 20 tons per hour, which may be sufficient given the high speed and the low air pressure and the possibility of working at higher temperatures thanks to the short residence time and the cooling of the grains before leaving the reactor.
• This assembly can be made compact and easily transportable, which shows the advantage of being able to pass through a dense fluidized bed by a very large amount of fluid at high speed through the centrifugal force.
• EXAMPLE 3 COPOLYMERIZATION OF METHYLENE AND GAS-PHASE DOCTENES USING A DEVICE FOLLOWING THE INVENTION
• the copolymerization of ethylene and octene is possible in the gas phase only if the pressure in the reactor is low, at most a few times the atmospheric pressure, since the partial pressure of the octene is limited to about 0, 2 atmospheres at 70 ° C. At these pressures, the amount of calories produced by these highly exothermic reactions can be removed only by using little active catalysts or by diluting the active gas mixture with an inactive gas to slow down the rate of reaction, which increases the cost of the installation, or by passing through the fluidized bed by such a quantity of gas that it requires a rotating fluidized bed, for example according to the diagram described in FIG.
• the octene can be sprayed into fine droplets (120) in the reaction chamber through the tube (121) which passes through the central stack and / or fed in the gaseous form together with the fresh ethylene (119) and the fluid recycled by one or more of the tubes of (8.1) to (8.4).
• the cylindrical reaction chamber may, for example, have a diameter of 1.6 m; 10 m long and 0.32 m thick, comprising 29 injection slots 0.005 m thick, allowing the injection of approximately 50 m 3 / s of active fluids, if the injection speed of fluid is 35 m / s.
• the flow of recycled active fluids is about 700 tons per hour, which allows to evacuate the polymerization heat of about 10 to 20 tons per hour of polymer.
• the amount of polymer in the reaction chamber having a volume of about 12 m 3 is about 3 tons, giving a residence time of the polymer particles in the reaction chamber of 10 to 15 minutes, allows the use of very active catalysts.
• the rotational speed of the polymer particles can be about 11 m / s, which gives a centrifugal force of about 16 times the gravity, which allows to pass through the fluidized bed with a radial velocity of more than 1.5 m / s in about 0.2 seconds.
• This reactor can be put in series, for example following another reactor that can work at much higher pressures without comonomer or with lighter comonomers, in order to obtain multimodal polymers. It also makes it possible to progressively vary the composition and / or the temperature of the fluid passing through the rotating fluidized bed.
• EXAMPLE 4 IMPREGNATION OR COATING OF WELD PARTICLES USING A DEVICE FOLLOWING THE INVENTION
• the diagram of FIG. 10 can also be used for the impregnation or coating of solid particles.
• the impregnating or coating fluid may be sprayed as fine droplets (120) into the portion of the reaction chamber which is located on the solid particle supply side by the tube (16). These particles are then dried in the successive annular sections of the circular reaction chamber and the components used for impregnation or coating of the solid particles can even be fired, if the temperature of the recycled fluid is sufficiently high and the particles solids can be recycled by a suitable device, if it is necessary to apply several layers of coating.
• Figure 17 illustrates a simplified diagram, similar to Figure 11, slightly modified to allow for bimodal or multimodal co-polymerization of solid particles as a catalyst, suspended in fluids or mixtures of active fluids, containing the monomer and the comonomer (s), such as, for example, the bimodal catalytic copolymerization of ethylene with hexene.
• the reactor (201), its cylindrical axis of symmetry (202), the hollow sections of the hollow discs (203) separating the reactor into two sets of two successive cylindrical chambers from Z1 to Z2 and Z3 to Z4 are recognized therein.
• the polymer particles, symbolized by the black dots, emerging from the top of the reactor through the tube (230) are introduced into a recycling tube which may be a purification column (261), through which the fluid injected in (204.1) passes. fluidising the polymer particles which form a surface fluidized bed (262), the fluid escaping at (266) through the particle separator (267) for recycle by the compressor (218).
• the polymer particles are then recycled through the tube (226) to the bottom of the reactor. After having traversed a certain number of cycles, they (229) are evacuated by tubes (230.1), which can be arranged along the side walls of the various cylindrical chambers.
• the feed of fresh monomer, such as ethylene can be introduced: partly (204.1), at the bottom of the purification column and be recycled to the upper part of the reactor after purging the polymer particles of the copolymer.
• excess monomer like hexene, which they contain; partly in (204.2), to facilitate the recycling of the polymer particles, although the hydrostatic pressure of the fluidized bed of the column (261), determined by the equilibrium level of its surface (262), may be sufficient and partly in the pressure balancing tube (245) to prevent pressure equalization between the upper and lower cylindrical chambers from causing undesirable transfers of fluids between these sets.
• the co-monomer (263), such as hexene, can be sprayed into fine droplets on the surface of the fluidized beds of one or more upper cylindrical chambers by injectors (264), which pass through the hollow discs and the catalyst can be introduced by a suitable device (265) into one of the cylindrical chambers.
• injectors such as hydrogen
• Other active components such as hydrogen, and other monomers can be introduced into one of the recycle circuits, and their excess can be removed in the other recycle circuit, for example by absorption in recirculating absorbers. generable.
• additional non-active cooling fluids such as propane or isobutane, may be sprayed into fine droplets on the fluidized beds in the same manner as the comonomer.
• This scheme makes it possible to limit the unwanted transfers of fluids from one assembly to the other, to the fluids not eliminated by the purification column (241) and to the fluids accompanying the polymer particles in the passage or passages (227) which connect the cylindrical chambers Z2 and Z3, and whose size can be limited according to the polymerization objectives.
• the accessories of controls, purifications, etc. including the possibility of cooling the hollow discs, the purification column and other surfaces arranged inside the chambers, are not described. They can be defined according to the polymerization objectives by the people controlling the fluidized bed polymerization processes.
• FIG. 18 illustrates a simplified diagram, similar to that of FIG. 17, slightly modified in order to allow the catalytic conversion of a fluid or mixture of fluids, in a rotating fluidized bed containing solid catalytic particles, for example, cracking. catalytic light olefins.
• the fluid to be converted (204) is injected, preheated if necessary, into the distributor (s) (205) which feeds the set of lower cylindrical chambers, Z1 and Z2. It is evacuated from these chambers by the collector (s) (217), to be reheated in the heater (219), and recycled by the distributor (s) (205.1) into the set of upper cylindrical chambers, Z3 and Z4, d. where it is sucked through the collector (s) (217.1) by a single compressor (218) to be transferred (220) to suitable processing units.
• the fresh or recycled catalyst powder is fed into the cylindrical chamber Z1 of the bottom of the reactor through the tube (226) and slowly rises from one chamber to the other, to the top of the reactor where it is evacuated by the tubes (230) to a regeneration column (261).
• a regeneration fluid (204.1) for example a mixture of air and water vapor, fluidifies the catalyst powder in the regenerator, while regenerating it. It is evacuated in (266) through a particle separator (267).
• the equilibrium level of the surface (262) of the fluidized bed of the column (261) is that which gives a hydrostatic pressure sufficient to allow the regenerated catalyst powder to be recycled to the desired flow rate. This recycling can be facilitated by the injection of a driving fluid, (204.2), such as water vapor.
• the series supply of the two sets of cylindrical chambers causes a significant pressure difference between the chamber Z2 and the chamber Z3, which will accelerate the catalyst particles and the fluid that accompanies them in the passage (227) connecting them.
• the ratio between the density of the fluidized bed and the fluid is very high, it is necessary not only a very high fluid flow, but also a high injection speed, it is desirable to use a suitable energy transfer device and amount of fluid movement to the catalytic particles, before the fluid has lost a substantial portion of its velocity due to its expansion in the open space of the cylindrical chambers.
• the number of rooms and sets may vary.
• the accessories of controls, purifications, etc .... are not described. They can be defined according to the objectives, by those who master fluidized bed catalytic transformation processes.
• the outgoing fluid coming from the upper set of cylindrical chambers is at a lower pressure, which is generally favorable for the conversion of the fluid, but it is in contact with the catalyst that must be regenerated, which is unfavorable. and requires cycle times between two shorter regenerations.
• This can be avoided by adding a second compressor before the heater (219) to equalize the pressures in the two sets of cylindrical chambers, which allows to reverse the flow of the fluid, ie to feed the fluid to be transformed in the upper set and remove the transformed fluid from the lower set.
• the drying of solid particles, such as cereal seeds can be done with air at a pressure close to atmospheric pressure, it is possible, thanks to this process, to make it in light units, compact and easily transportable, as described in Figures 19 to 22.
• Figure 19 shows the longitudinal section of a horizontal reactor, which can work at a pressure slightly lower than atmospheric pressure. It shows the section (201) of its wall, its cylindrical axis of symmetry (202) and the hollow sections (203) of the hollow discs which separate the reactor into five successive cylindrical chambers, from Z1 to Z5.
• the distributor (205) is traversed by a longitudinal slot, symbolized by the thin line (269) and is connected by plates, replacing the tubes (206) and schematized by the rectangle (270), with long longitudinal slots over the entire reactor length, symbolized by the rectangle (207), dividing the cylindrical wall of the reactor into two half cylinders and designed to inject the fluid (204) perpendicularly to the plane of the figure, that is to say tangentially in the reactor. While rotating, the fluid passes, at a radial velocity (208), the fluidized bed, whose surface
• the thickness of the fluidized bed is less and therefore the axis of symmetry (202.1) of the surface of the fluidized bed is slightly lower than the axis of symmetry (202) of the reactor.
• the distance between these two axes, ⁇ which is approximately equal to half the difference in thickness between the top and bottom of the fluidized bed, is approximately ⁇ E.
• the fluid (210) then enters through the central openings of the hollow discs (203), widened (212) around them.
• the fluid (213) exits the reactor through the openings (214), in fine lines, which are long transverse slits cut into the side wall of the hollow discs which are widened (215) around them and it enters through the nozzles (216) in the section manifold (217) and is sucked by a fan (218).
• Tubes (271) passing through the ends or covers of the reactor, can also evacuate the fluid centrally. Then part of the fluid is discharged to (220) through a control valve (224). Its flow is approximately equal to the flow fluid supplied with (204).
• the remainder of the fluid is treated, for example, dried with a condenser and / or heated, at (219), and then recycled (223) through the opposite end of the dispenser (205).
• the fluid can be recycled on average several times before being discharged, if the flow rate of the recycle fluid (223) is several times greater than the feed rate (204). and therefore also the discharge rate (220), but, because of its mixing in the fan (218) a small fraction of the fluid will be removed from its first passage in the reactor. This can be avoided by using a second fan, (218.1) as shown in the diagram of Figure 11.
• the solid particles (225) are introduced into the reactor through the tube (226) by suitable means and are transferred from one chamber to another through the passages (227).
• the particles will first fill the first cylindrical chamber, Z1, until the level of the surface (209) of the fluidized bed reaches the level of the first passage (227). Then the particles can begin to fill the second cylindrical chamber and so on until the level of the last cylindrical chamber, Z5, arrives at the exit opening of the particles (229) through the tube (230). allowing their exit from the reactor.
• secondary passages (227.1) must be provided, located against the side wall of the reactor to allow a gradual and more or less uniform filling of all the cylindrical chambers to prevent large differences in fluid flow rates in the injection slits from transferring the energy required to rotate the solid particles in the filling areas.
• the transfer rate depends on the rotational speed of the solid particles, the dimensions of the passages and their profile and the differences in level of the surface of the fluidized bed from one chamber to another. The latter can be accentuated or diminished by tilting the reactor. Particle rotation is ensured by the transfer of momentum from the fluid to the particles, in order to compensate for energy losses due to turbulence, friction and their transfers in the reactor and from one chamber to another . This amount of movement can be increased by placing side deflectors, (not shown in this figure) adequately profiled in front of the injectors. Energy losses can be minimized by taking care of the internal aerodynamics of the cylindrical chambers.
• the emptying of the reactor in case of malfunction, can be provided by openings arranged in the bottom of each zone and a filter or particle separator can be installed upstream of the fan (218) or the outlet (220) to avoid send solid particles downstream of the installation.
• the central openings of the hollow discs can be connected by central deflectors, such as those (313) described in FIG. 12, and their inputs can be located in the upper part of the reactor to minimize the risk of particle aspiration, especially during untimely stops.
• FIG. 20 represents the view of a section crossing a hollow disk, along the plane AA 'of FIG. 19, for a reactor having two distributors and two collectors and forming with these It is a compact package that is easily transportable and designed to be easily dismantled. It shows the section (201) of the side wall of the reactor, the section (205) of two distributors, their longitudinal slots (269), perpendicular to the plane of the figure, and plates (270) for injecting the fluid (204) through the slots (207) passing longitudinally (perpendicular to the plane of the figure) the reactor wall, dividing it into two half cylinders.
• They are preferably arranged at approximately the same height on each side of the reactor, so that the flow rate of the fluid passing through them is not affected by differences in hydrostatic pressure inside the fluidized bed. They are framed by the plates (273), which are welded or extend the side wall (201) of the reactor and which are releasably connected to the plates (270) of the distributors (205) by the fasteners (274). Their spacing is maintained by inserts (275) arranged regularly along these longitudinal slots and profiled adequately to minimize their resistance to the flow of fluid that is injected into the reactor. This device opens the reactor by lifting its upper part.
• the widening (212) of the hollow disc around its central opening is delimited by two circles (276), in fine lines, and the two enlargements (215) at the periphery of the disc, around its lateral openings, are delimited by the curves (277), in fine lines.
• the interior of the hollow disk being apparent, one can see the section (278) of longitudinal members connecting its two parallel walls to maintain the spacing, to increase the rigidity of the assembly and to guide to the openings in its side wall (279) the fluid (280) which rotates rapidly as it enters the hollow disk.
• the fluid (213) then leaves the hollow disc and enters the two section manifolds (217) through the nozzles, which is seen a face (216) and whose end (281), fine line, is welded to the manifold (217) and whose other end, which enters the transverse slot of the reactor, is welded to the side wall of the reactor and enters the interior of the hollow disc through the slots in its side wall (279).
• the circular end (282) of the nozzle (216) is pressed against the bottom wall of the hollow disk and the lateral sides of the nozzles, whose sections (283) are seen, are folded at their end (284) to facilitate their insertion. in the openings of the side wall of the hollow disc, during assembly of the reactor.
• Triangular spars (285) connect the opposing walls of the nozzles to increase their rigidity and their suitably profiled ends (286) penetrate the hollow disc to guide these nozzles inside the disc when assembling the two parts of the disc. reactor.
• the ends (282) and (284) of the nozzles (216) have dimensions that allow them to fit easily and sufficiently tightly into the side openings of the hollow discs.
• the passages which allow the transfer of particles from one zone of the reactor to the other through the hollow disk are arranged, for example, along the edges of the hollow disk, (227.1), and closer to its center, ( 227.2). They are delimited by the walls (287) perpendicular to the plane of the figure and the inclined walls (252) which guide the solid particles moving in the direction (289) from the area of one side of the disc to the area of the 'other side. If a transfer of the solid particles in both directions is desirable to obtain a reflux, for example heavier particles, some passages, for example near the reactor wall, may be inclined in the contrary.
• FIG. 21 is an enlargement of the fluid injection device shown in FIGS. 19 and 20. It shows, in hatched form, a piece of the section (201) of the side wall of the reactor, the distributor (205), the plates (270) and (273) connecting the longitudinal slot (207), perpendicular to the plane of the figure, in the wall of the reactor to the longitudinal slot (269) of the fluid distributor (205) (204), and in lines thin, the fastener (274) which allows to assemble the lower part of the reactor, on the left of the figure, with its upper part, on the right, and the section of the insert (275) which ensures the spacing of the plates (273) one of which is an extension of the wall (201) of the upper part of the reactor, on the right, and the other is welded to the lower part of the reactor, on the left.
• the side wall (279) of the hollow disk and a passage (227.1) along the side edge of the hollow disk, defined by a side wall (287) and inclined walls (288) which guide the particle streams (289) of the area below the hollow disk at the area above the hollow disk are also visible in this figure.
• Figure 22 shows the view of a section along the plane BB 'perpendicular to Figure 20, the nozzle connecting a hollow disk to a collector. It shows the outer surface of the collector (217), the inner surface of the lateral side (279) of a hollow disc and the section (203) of its two parallel walls, the two circular ends (282) and the ends (284).
• a unit of industrial size may, for example, have cylindrical chambers of 3 m diameter and 1.8 m high. If the ethylene pressure is about 25 atmospheres and the concentration of the particles in the fluidized bed is about 35%, the ratio of fluidized bed and fluid density is about 11.
• Central openings of 0.8 m diameter hollow discs make it possible to easily evacuate a recycled ethylene flow rate of 5 ⁇ Wsec per cylindrical chamber, ie approximately 500 tonnes per hour. If the polymer particles are transferred from one chamber to the other at a rate of 125 liters per second, or about 150 tons per hour and a little more if the profile of the passages is designed to increase the concentration of particles in order to reduce unwanted fluid transfers from one chamber to another, an average fluid injection rate of about 20 m / sec and an efficient transfer of the momentum of the fluid to the polymer particles can make it possible to do so rotate at an average speed of more than 6 m / s, sufficient to obtain a fluidized bed vertical rotary.
• the thickness at their bases may be about 0.9 m, giving a fluidized bed volume of nearly 7 m 3 per cylindrical chamber, or about 2.3 tons of polyethylene.
• the use of helical spirals or other suitable means makes it possible to increase the thickness at the tops of the chambers while decreasing it at their bases, which can allow a volume of the fluidized bed of 7.5 m 3 or 2.5 tons of polyethylene, while reducing the differences in pressures, velocities and residence time of the fluid in the fluidized bed between their bases and their vertices.
• the average residence time of the polymer particles in each cylindrical chamber is about 1 minute and that of the fluid in the fluidized bed is 1.5 seconds.
• the reactor comprises 10 cylindrical chambers, which can be grouped into two or more sets having separate recycling circuits, to obtain a composition of the bi or multimodal polymer particles, the total volume of recycled fluid is 50 m 3 / sec, approximately 5,400 tonnes per hour, which makes it possible, without the aid of refrigerant fluids, to cool a production of at least 50 tonnes of polymer per hour with an average residence time of the particles of 30 minutes, allowing them about 3 complete cycles on average, which ensures a reasonable homogeneity of the polymer particles, while limiting the transfer of undesirable fluids between the different parts of the reactor.
• the amount of polymer particles transferred from one chamber to another can be increased by increasing the dimensions of the passages, which also increases the quantity of polymer particles. unwanted fluids transferred from one set of chambers to another and can therefore reduce their differentiation.
• the volume of ethylene supplying the reactor is approximately 0.5 m 3 / sec, ie approximately 6 times the volume of fluid transferred with the particles from one chamber to another and therefore also in the purification column (61 ), it is easy to purge the particles of this hexene-containing fluid using a part of this ethylene in this column, given the possibility of having a lower concentration of hexene in the upper cylindrical chamber, if hexene is sprayed only in the lower cylindrical chambers of the upper assembly.
• the lower set of cylindrical chambers contains a high concentration of hydrogen to decrease the molecular weight of the high density polyethylene produced therein, a small amount of this hydrogen is transferred to the upper set (s) of the reactor together with the polymer particles.
• a hydrogen absorber which can be inserted in the fluid recycling circuit (s) of the at least one higher assembly. It is the surface of the fluidized bed of about 12 m 2 per chamber, ie 120 m 2 in all, for an average thickness of the fluidized bed of about 0.6 m and the centrifugal force, which allow a flow of fluid as well. high and a residence time of the fluid in the fluidified bed so short.
• the catalytic cracking of gasoline olefins from catalytic crackers is carried out at high temperature and at low pressure, close to atmospheric pressure. It is very endothermic, which justifies working in two successive passes with intermediate reheating, which requires the circulation of considerable fluid volume.
• the catalyst is progressively coated with carbon, and all the more quickly that the fluid to be cracked is heavier, which justifies a circulation of the catalyst with continuous regeneration.
• the average cycle time between two regenerations depends on the working conditions. It can be less than an hour to several hours.
• an industrial reactor can have cylindrical chambers of 1, 6 m diameter and 1, 5 m high. If the ratio of the fluidized bed and fluid density is 150, a recycled fluid flow rate of 2.4 m 3 / sec, injected at an average velocity of 50 m / sec, can cause the catalyst particles to rotate rotation speed greater than 4 m / sec, sufficient to obtain a vertical rotating fluidized bed. As the differences in the rotational speeds of the particles, the pressures and the thicknesses of the fluidized bed between the top and the bottom of the chambers can be quite high, it is desirable to equip them with ascending helical spirals or other devices making it possible to reduce them. .
• the reactor has two sets in series of four cylindrical chambers each, which gives it a height of more than 12 meters, given the thickness of the hollow discs necessary for the evacuation of the fluids, it can crack about 200 tons per day. hour, if the density of the heated fluid is 6 gr / liters.
• the pressure difference between the inlet and the outlet of each set of cylindrical chambers, necessary to compensate for the hydrodynamic pressure of the fluidized bed and to inject the fluid at the desired speeds, may be less than a quarter of the atmospheric pressure. If the pressure drop in the heating furnace is sufficiently low, the supply of the two parts of the reactor being in series, the pressure difference between these two parts may be less than 50% of the atmospheric pressure, compared to the pressure hydrostatic fluidized bed in the recycle column (61), which can be close to atmospheric pressure for a height of 11 m, which is sufficient to recycle the regenerated catalyst particles.
• One of the advantages of this series configuration is the lower pressure of the fluid in the outlet reactor, which favors its conversion.
• a horizontal reactor as described in Figures 19 to 22, forming with these accessories a set the size of a container easily transportable, can be 1, 8 m in diameter and be divided into 6 cylindrical chambers 0.5 m wide.
• the wet grains (225) are introduced through the tube (226) into zone Z1. They are heated and dried by recycled air, which is heated by the exchanger (219) and possibly dried, if necessary, by a condenser not shown.
• the grains are transferred from one cylindrical chamber to the other until the last chamber, Z6, where they are cooled by the fresh air (206) which they preheat while completing their drying before going out (229) by the tube (230).
• the air is reheated, dried and recycled in the other zones, a number of times equal to the ratio of the total flow of the fan and the flow of the exhaust air in (220).
• the displacement of the fluid inside the fluidized bed being substantially parallel to the surface of the fluidized bed and the centrifugal force allowing a radial velocity perpendicular to this relatively high surface, the difference in speed between the air and the grains and the air flow can be relatively high, which reduces the time required for drying.
• the grains being cooled by fresh air before leaving the reactor and their residence time in the reactor being relatively short, they can be heated to slightly higher temperatures than in a conventional dryer.
• the moist air being slightly cooled by the grains it preheats before leaving the reactor, the use of calories is very effective.
• This efficiency can be improved by using a second, smaller fan, which directly discharges the air leaving the first cylindrical chamber, which served to preheat the grains and which can be isolated by a separation in the first hollow disk, without it is mixed with the air coming from the other cylindrical chambers.
• small side passages (227.1) along the side wall of the reactor can provide a preferential transfer of the heavier grains, and therefore the more difficult to dry in the opposite direction, in order to increase their residence time in the reactor.
• the ratio of this density and the ambient air is about 230, which requires an air flow and a very high injection speed.
• an airflow of 2 m 3 / sec per chamber, ie more than 9 tons per hour per chamber, injected at about 40 m / sec and an efficient transfer of momentum from the air to the grains can give grain rotation speeds of more than 6 m / sec, giving a difference in thickness between the top and bottom of a fluidized bed of average thickness of 30 cm, less than 12 cm.
• the total air flow rate of 12 m 3 / sec can be supplied by a fan in two 0.65 m diameter distributors and discharged via two 0.7 m diameter collectors, the central openings of the hollow discs being be less than 0.6 m in diameter. This makes it possible to contain the assembly formed by the reactor, its distributors and collectors in a square of 2.5 m side, corresponding to the size of a standard container.
• the volume of the fluidized bed is about 700 liters per chamber, or 4.2 m 3 in all, for a surface of more than 11 m 2 . If the grain transfer from one chamber to another is 20 liters per se- about 20 tons per hour, their average residence time in the dryer is about 3.5 minutes. Their degree of drying depends on the degree of humidity and the temperature of the air which can be warmed, among others, by the cooling of the fan motor, and can pass through a condenser, but in a general way it is faster than in an ordinary dryer, given the great difference in velocities between air and grains, obtained thanks to their tangential direction and centrifugal force.

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