FR3054143A1 - COKE ANCHORING DEVICE FOR A WALL OF AN ENCLOSURE OF AN FCC UNIT AND CORRESPONDING CYCLONE. - Google Patents

Abstract

The invention relates to a coke anchoring device (10) for retaining the coke formed on a wall of an enclosure of a fluid catalytic cracking unit. The device (10) includes a hollow tube (101) of predetermined length and a coke anchor (102) integral with the outer surface (101b) of the hollow tube. In particular, the anchoring device is fixed on a double wall to be protected (30), formed of an inner wall (301) and an outer wall (302) defining between them a chamber (303). A plurality of anchoring devices (10) each associated with an orifice (305) of the outer wall (302) are fixed thereto, each orifice (305) being extended by a hollow tube (101) of a device anchor (10). This double wall (30) may form the lower end of a gas evacuation pipe of a mechanical particle separation cyclone suspended in a gaseous fluid, in particular for a fluid catalytic cracking unit.

Description

054 143

57018 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY

COURBEVOIE © Publication number:

(to be used only for reproduction orders)

©) National registration number © Int Cl ⁸ : B 01 J 8/24 (2017.01), B 01 J 19/02, C10G 75/00, 47/28, B 04 C 11/00

A1 PATENT APPLICATION

©) Date of filing: 07.22.16. © Applicant (s): TOTAL REFINAGE CHIMIE Company (© Priority: anonymous— FR. @ Inventor (s): LESAGE ROMAIN. ©) Date of public availability of the request: 26.01.18 Bulletin 18/04. ©) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ® Holder (s): TOTAL REFINAGE CHEMISTRY Company related: anonymous. ©) Extension request (s): © Agent (s): CABINET FEDIT LORIOT.

COKE ANCHORING DEVICE FOR A WALL OF AN ENCLOSURE OF AN FCC UNIT AND CORRESPONDING CYCLONE.

FR 3 054 143 - A1 (ü /) The invention relates to a coke anchoring device (10) intended to retain the coke forming on a wall of an enclosure of a fluid catalytic cracking unit. This device (10) comprises a hollow tube (101) of predetermined length and a coke anchoring element (102) integral with the external surface (101 b) of the hollow tube.

In particular, the anchoring device is fixed to a double wall to be protected (30), formed by an internal wall (301) and an external wall (302) defining between them a chamber (303). A plurality of anchoring devices (10) each associated with an orifice (305) of the external wall (302) are fixed thereto, each orifice (305) being extended by a hollow tube (101) of a device anchor (10). This double wall (30) can form the lower end of a gas discharge pipe from a cyclone for the mechanical separation of particles suspended in a gaseous fluid, in particular intended for a fluid catalytic cracking unit.

201

COKE ANCHORING DEVICE FOR A WALL OF AN ENCLOSURE OF AN FCC UNIT AND CORRESPONDING CYCLONE

The invention relates to a coke anchoring device for a wall of an enclosure of a fluid catalytic cracking unit (FCC "Fluid Catalytic Cracking"). The invention also relates to a cyclone for the mechanical separation of particles suspended in a gaseous fluid equipped with the coke anchoring devices of the invention, and to a fluid catalytic cracking process using such anchoring devices.

In a fluid catalytic cracking unit, cyclones are used to separate the catalyst particles from the gases flowing in the unit. These are devices that use centrifugal force to mechanically separate particles suspended in a gas. Cyclones comprise an enclosure, generally essentially cylindrical-conical, designed to impose a rapid rotation on the gas introduced into the enclosure, for example by bringing the gas tangentially to the circumference of the enclosure, in the vicinity of the wall. Under the effect of the centrifugal force, the solid particles taken in the vortex move towards the wall, lose their speed there by friction and fall in the lower part of the apparatus, before leaving by the apex of the cone. The gas follows the wall to the vicinity of the apex, and once freed of the particles, rises to the upper part to exit via an evacuation pipe, which projects in part inside the enclosure.

The cyclones used in an FCC unit have metal walls, generally made of stainless steel, which are generally covered with a coating intended to protect them mainly from erosion.

Under certain conditions of use, for example in FCC reactors, the formation of coke is observed on the part of the wall of the gaseous fluid discharge pipe located inside the enclosure, more precisely on the surface. external of this wall. During thermal cycles (unit stop / start), it often happens that the coke comes off and falls into the solid particles evacuation pipe (generally called dipleg). This can lead to blockage of the dipleg and therefore to significant losses of solid particles, which is particularly damaging when these particles are catalyst particles. It may then be necessary to stop the unit to:

- unblock the diplegs by removing the coke and catalyst which are blocked there,

- remove the coke which is hung on the gas outlet tube of the cyclones,

- clean a fractionation section located downstream of the reactor, to which catalyst particles could have been sent.

In order to limit the fall of the coke formed, it is known to have anchoring devices on the external surface of the pipes for discharging the gaseous fluid. These are protruding metallic elements (sometimes called “bullnose” or “coke anchor” in English), fixed on the surface of the wall, in particular on the covering which covers it, and on which the coke formed will hang. . These anchoring elements limit the fall of the coke, and, in the event of a fall, limit the size of the loose pieces of coke, thereby reducing the risk of clogging of the dipleg. Document FR 2 910 342 A1 describes anchoring devices of this type.

It is also known to limit the formation of coke by creating a layer of protective gas on the external surface of this wall. Document CN1330428C thus proposes to double this wall with a porous external wall and to inject gas through the porous wall in order to form a film on the external surface of the wall. However, the possible formation of coke can lead to blockage of certain pores of the porous wall, to the detriment of the formation of the protective gas layer. In addition, it is then not possible to cover the porous outer wall with an erosion protection coating, which is essential in an FCC unit.

The invention aims to overcome these drawbacks by proposing a coke anchoring device which makes it possible both to reduce the formation of coke and to retain any coke that may have formed.

To this end, a first object of the invention relates to a coke anchoring device intended to retain the coke forming on a wall of an enclosure of a fluid catalytic cracking unit, said anchoring device comprising a tube hollow of predetermined length and a coke anchoring element secured to the external surface of the hollow tube.

It is thus possible to circulate a gaseous fluid through the hollow tube which can make it possible to form a layer of gas on the surface of a wall, even if the latter is covered with a protective coating. In addition, the presence of the anchoring element ensures the retention of any coke formed.

The anchoring device according to the invention may also have one or more of the following characteristics:

- the anchoring element is fixed to the external surface of the hollow tube by force assembly, by clipping, screwing or welding. It can thus be removable or not. In particular, in particular in the case of fixing by screwing, for example by means of a thread made on the external surface of the hollow tube, it is possible to fix the anchoring element at a chosen position on the hollow tube . One can also consider an anchor made in one piece with the hollow tube.

- the anchoring element comprises a fixing part fixed to the hollow tube and at least one retention element forming an acute angle with a longitudinal axis of the hollow tube. This configuration can favor the retention of coke on a wall, in particular when the opening of the angle is directed in a direction opposite to the wall.

- Said at least one retention element is a metal wire. Preferably, two retention elements defining a V are integral with the fixing part.

Another object of the invention relates to a cyclone for the mechanical separation of particles suspended in a gaseous fluid, in particular intended for a fluid catalytic cracking unit, said cyclone comprising the following elements:

a separation enclosure, in particular shaped to separate the particles from the gaseous fluid, a first pipe opening into the interior of the enclosure for the supply of the gaseous fluid loaded with particles, a second pipe intended for the evacuation of the gaseous fluid, located in the upper part of the enclosure and a lower end of which is situated inside the enclosure, a third pipe intended for the evacuation of particles, located in the lower part of the enclosure, in which the end bottom of the second pipe has a double wall formed by an internal wall and an external wall defining between them a chamber connected to a gas supply pipe, the chamber being in fluid communication with the interior of the enclosure through a multitude of orifices passing through the external wall.

This cyclone comprises a plurality of anchoring devices according to the invention, each associated with an orifice in the external wall, in which each orifice is extended by a hollow tube of an anchoring device extending inside the enclosure.

The chamber is therefore in fluid communication with the interior of the enclosure via the multitude of orifices passing through the external wall and the hollow tubes of the anchoring devices which extend them.

It is thus possible both to create a film of gaseous fluid on the surface of the external wall limiting the formation of coke and to fix to the anchoring elements the coke which would still be formed, further reducing the risks of stopping of unity due to the formation of coke.

The cyclone according to the invention may have one or more of the following characteristics:

- each hollow tube of an anchoring device extends substantially perpendicular or perpendicular to the surface of the external wall,

- one end of each hollow tube of an anchoring device is inserted into the orifice which it extends, for example inserted by force,

the outer wall of the second pipe is covered with a protective coating of predetermined thickness, each hollow tube of an anchoring device projecting from the surface of the outer wall of a length sufficient to pass through the thickness of the covering and the anchoring element being fixed to a part of the hollow tube situated outside the covering. In particular, the protective coating may include a cellular anchoring structure integral with the external wall, the cells of which are filled with composite material, each orifice extended by a hollow tube then being located inside a cell, for example in the center of it. When the cells are hexagonal, an orifice extended by a hollow tube can be provided inside a central cell of each group of seven cells in which six cells share one side with the same central cell.

The invention also relates to a catalytic cracking reactor comprising at least one cyclone according to the invention.

Finally, the invention relates to a fluid catalytic cracking process comprising a reactor according to the invention, comprising:

a step of treatment in said reactor of a hydrocarbon feedstock in the presence of catalytic particles in the fluidized state in order to form gaseous effluents, a step of separation of the gaseous effluents produced and of the catalytic particles in at least one cyclone for mechanical separation of the reactor during which the chamber of each cyclone is supplied with a gaseous fluid which is introduced into the enclosure of the cyclone via the orifices of the external wall and the hollow tubes of the anchoring devices.

Preferably, the gaseous fluid is not likely to react under the reaction conditions. This is for example water vapor or another fluid.

The invention is now described with reference to the accompanying non-limiting drawings, in which:

Figures la, lb and the respectively represent a top view and two side views at 90 ° from one another of an anchoring device according to an embodiment of the invention;

Figure 2 is a schematic representation of a cyclone;

Figure 3 is a sectional view of a double wall of the gas discharge pipe of the cyclone shown in Figure 2 according to one embodiment;

Figure 4 is a sectional view of a double wall of the gas discharge pipe of the cyclone shown in Figure 2 according to another embodiment;

Figure 5 is a front view, laid flat, of the outer wall of the double wall of the discharge pipe covered with a coating;

FIG. 6 is a detail view of FIG. 5.

In the present description, the terms "upper", "lower" refer to a vertical direction, corresponding to the direction of gravity, in a position of use of the cyclone. In this position of use, the longitudinal axis of the cyclone is substantially vertical.

By substantially horizontal, longitudinal or vertical, is meant a direction / plane forming an angle of at most ± 20 °, or even at most 10 ° or at most 5 °, with a horizontal, longitudinal direction / plane or vertical.

By substantially parallel, perpendicular or at right angles, is meant a direction / angle deviating by at most ± 20 °, or even at most 10 ° or at most 5 ° from a parallel, perpendicular or at a right angle.

FIGS. 1a, 1b, represent a coke anchoring device 10 according to an embodiment of the invention. This anchoring device 10 comprises a hollow tube 101 of predetermined length and a coke anchoring element 102 integral with the external surface 101a of the hollow tube 101.

The fixing of an anchoring element 102 to a hollow tube 101 of an anchoring device 10 can be obtained by clipping, screwing or welding, or by force assembly. In the case of a screwing, the external surface 101a of each hollow tube 101 may for example have a thread on which a nut 104 can be threaded, as visible in FIGS. 1b and 1c. In this embodiment, the nut 104 is integral with the anchoring element 102 to which it can be fixed by welding. It is understood that the anchoring element 102 can then be threaded with its nut 104 onto the hollow tube 101 and positioned in the desired position. The installation of another nut on the other side of the anchoring element 102 relative to the nut 104 makes it possible to rigidly fix the anchoring element 102 in the desired position when the nut 104 rests on a surface, as will be described with reference to FIGS. 3 and 4. It is possible to fix the anchoring element 102 to the hollow tube 101 in the same way if the nut 104 is not secured to the anchoring element 102. Note that the nut 104 (or a support washer or the like) could also be welded to the hollow tube 101 to retain the anchoring element 102, or else the thread of the hollow tube may not extend from one end of the hollow tube to the other.

The invention is not limited to a particular method of fixing, provided that the anchoring element 102 can be rigidly fixed to the hollow tube without hindering a circulation of fluid inside the hollow tube 101. One could thus envisage that the anchoring element 102 is itself threaded in order to cooperate with a thread made on the external surface 101a of the hollow tube. Force fitting or clipping of the anchoring element 102 is also possible. Finally, the anchoring element 102 and the hollow tube 101 could also be made in one piece.

In the embodiment shown in Figures la-le, the anchoring element 102 comprises a fixing part 102a fixed to the hollow tube 101 and at least one retention element forming an acute angle with a longitudinal axis 105 of the hollow tube 101.

Here, two retention elements 102b, 102c are provided. In the example shown, the fixing part 102a extends in a first plane (perpendicular to the longitudinal axis 105 of the hollow tube 101), the retention elements 102b, 102c extend in a plane perpendicular to the previously defined plane as shown in Figures la and le. In this plane, which is parallel to the longitudinal axis 105 of the hollow tube 101, the retention elements 102b, 102c are symmetrical with respect to the axis 105 and define a V shape with an angle of the order of 60 ° (figure lb). The fixing part 102a hugs here a part of the periphery of the hollow tube 101 (fig. La), but it could also surround it entirely.

The anchoring element 102 previously described consists of a metal wire. It is therefore very simple to carry out. The invention is not however limited to this type of anchoring element 102 and other forms of retention elements could be used, for example in the form of tongues, ... One or more than two elements of retention could also be expected.

FIG. 2 schematically represents a cyclone 20 located inside a reactor 50 (shown diagrammatically and not to scale). Cyclone 20 includes:

a separation enclosure 201, a first inlet pipe 202 opening into the enclosure 201, a second gas outlet pipe 203 located in the upper part of the enclosure 201 and a third particle outlet pipe 204 located in the lower part of enclosure 201.

The separation chamber 201, generally called the cyclone body, is shaped to separate the particles from the gaseous fluid. It is often cylindrical or sometimes cylindro-conical. In the example shown, the separation enclosure 201 comprises a cylindrical upper part 201a and a conical lower part 201b.

The smaller diameter lower end of this conical lower part 201b is connected to the particle outlet pipe 204, which is in the form of a tube extending in the axis of symmetry X (or longitudinal axis) of the separation enclosure 201. This tube is often called “dipleg” or “leg”.

The inlet pipe 202 receiving the gas / particle mixture, sometimes also called a hole or a horn, is formed of a tube arranged so as to induce a circular movement in the incoming mixture. Thus, the inlet pipe 202 can be tangential to the separation enclosure 201.

Under the effect of this movement, the particles present in the gas entering the cyclone fall into the conical lower part 201b of the separation enclosure 201 before being evacuated by the outlet pipe for the particles 204. The gas leaves as to him at the upper end of the cyclone via the gas outlet pipe 203, also called a chimney. A dust container 205 can be placed between the conical lower part 201b of the separation enclosure 201 and the particle outlet pipe 204.

The example described refers to a cyclone arranged vertically. The invention is however not limited to such an arrangement, nor to this cyclone structure.

The lower end 203a of the second pipe 203 projects inside the separation enclosure 201. This lower end 203a has a double wall 30 formed by an internal wall 301 and an external wall 302 defining therebetween a chamber 303 connected to a pipe 304 for supplying gaseous fluid. In the example, these walls 301 and 302 are concentric. The structure of this double wall 30 is now detailed with reference to FIGS. 3 and 4.

The chamber 303 is in fluid communication with the interior of the enclosure 201 via a multitude of orifices 305 passing through the external wall 302 and each extended by a hollow tube 101 of an anchoring device 10, this hollow tube 101 extending inside the enclosure 201.

An anchoring element 102 of the anchoring device 10 is also fixed to each hollow tube 101 on the side of the enclosure 201. It is noted that each hollow tube 101 projects from the surface 306 of the external wall 302 of a predetermined length, sufficient to allow the fixing of this anchoring element 102.

In the examples shown in Figures 3 and 4, the orifices 305 and the hollow tubes 101 have axes of symmetry combined. These axes are also perpendicular to the surface 306 of the external wall 302. In these examples, the hollow tubes 101 are inserted inside the orifice 305 which they extend, for example by force. They can be fixed to the external wall 302 by welding or any other suitable means. The invention is not however limited to this embodiment and the hollow tubes 101 could be fixed to the surface 306 of the external wall 302 around the periphery of the orifice 305. Other embodiments could be envisaged, provided that the chamber 303 can be in fluid communication with the interior of the enclosure via the orifices 305 and their hollow extension tube 101.

The length of the hollow tubes 101 projecting from the surface 306 of the external wall 302 can be identical for each hollow tube 101 or not.

In order to facilitate their positioning, the anchoring elements 102 are preferably fixed to an external surface 101a of each hollow tube 101, for example as described above with reference to the anchoring device 10.

In Figures 3 and 4, the anchoring device 10 is similar to that described with reference to Figures la-lc. The invention is however not limited to a particular form of anchoring device provided that the latter comprises a hollow tube and a coke anchoring element. It will be noted that the two retention elements 102b, 102c are directed towards the enclosure 201 when the fixing part 102a of the anchoring element is secured to the hollow tube 101. In other words, the acute angle formed by each element of retention 102b, 102c with the axis 105 of the hollow tube is open in a direction opposite to the external wall 302.

In the embodiment shown in FIG. 3, the anchoring element 102 is held tight against the surface 306 of the external wall 302 by means of a nut 106.

In the embodiment shown in FIG. 4, the anchoring element 102 is held on the hollow tube 101 by means of two nuts 104, 106, the anchoring element 102 being interposed between these nuts, the one 104 rests on a surface of the external wall and the other 106 is screwed from the other anchoring element 102.

The invention is not limited to a particular method of fixing provided that the anchoring element 102 can be rigidly fixed to the hollow tube 101, without hindering the communication of fluid between the chamber 303 and the enclosure 201. It will be noted that a fixing with the possibility of adjusting the position of the anchoring element 102 relative to the hollow tube 101 makes it possible to use the same anchoring device for various uses for which it may be desirable not to position the anchoring element 102 in the same position relative to the hollow tube 101.

In the example shown in Figure 4, the surface 306 of the outer wall 302 is covered with a coating 40 of predetermined thickness. This coating 40 protects the outer wall 302 from erosion. It will be noted that each hollow tube 101 projects from the surface 306 of the external wall 302 of a length sufficient to pass through the thickness of the covering 40 and allow the fixing of the anchoring element 102 outside this covering 40. The nut 104 is here in abutment against the surface 404 of the coating. The anchoring element 102 could nevertheless be directly in abutment against the surface 404, as in the example shown in FIG. 3.

In this example, the protective coating 40 comprises an anchoring structure 401 of the cellular type integral with the external wall 306, the cells of which are filled with composite material 402. The anchoring structure 401 is metallic and welded to the external wall 302. The composite material is preferably a material resulting from an assembly of at least two immiscible materials having a high adhesion capacity. Preferably, the composite material is a composite building material such as concrete, in particular concrete suitable for use in a fluid catalytic cracking unit.

Figures 5 and 6 show the wall 302 shown flat for clarity, on which is fixed the anchoring structure 401 (the composite material is not present). In this example, the cellular anchor structure 401 is of the honeycomb type, each cell 403 being of hexagonal shape and surrounded by six other cells also of hexagonal shape to which it is connected by one side. This type of 401 anchor structure can be purchased under the trade name Hexmesh®.

It will be noted that in the example shown, a hollow tube 101 fitted with an anchoring element 102 is located in the central cell 403 of each group of seven cells in which six cells share one side with the same central cell. A regular distribution of the orifices 305 extended by a hollow tube 101 provided with an anchoring element 102 is thus obtained. The anchoring devices 10 are preferably located in the center of the cells 403.

The present invention is not limited to a particular distribution and / or to a particular positioning of the anchoring devices with respect to an anchoring structure 401, nor to a particular form of anchoring structure 401. In particular, any type of anchoring structure can be considered. It is thus possible to use bands in the form of S, K or other geometric shape, extending parallel to the wall, anchored in the wall by a support leg perpendicular to the wall. Such S or K-shaped bands are also called "S bars" or "K bars" in English and are rather used in isolation. Hexagon shaped anchor structures are also used in isolation for anchoring on surfaces with complex geometry. There are also honeycomb type structures with square cells formed by bands linked in pairs by rods forming axes of rotation (Flexmesh®).

A central position of an anchoring device relative to a cell of a honeycomb structure can facilitate the positioning of the anchoring structure and / or the anchoring device.

A regular distribution of the anchoring devices 10 can favor the obtaining of a regular gas layer over the entire external surface of the double wall 30 and / or favor the retention of the coke possibly formed.

The cyclone according to the invention is particularly well suited for use in a fluid catalytic cracking reactor, in particular in an upper zone of the reactor in which the catalytic particles are separated from the gaseous effluents. In this case, a gaseous fluid is injected via the pipe 304 into the chamber 303 in order to exit the external wall 302 via the tubes 101 and to sweep the surface 306 of the external wall or the surface 404 of the coating. Continuous gas scanning limits the clogging of the tubes 101 as well as the formation of coke. When coke is formed, however, it attaches to the anchoring elements 102 or, in the event of a fall, the arrangement of the anchoring elements limits the size of the pieces of coke that come off in order to reduce the risk of clogging of the solid exit from the cyclone.

Claims (12)

1. Coke anchoring device (10) intended to retain the coke forming on a wall of an enclosure of a fluid catalytic cracking unit, said anchoring device (10) comprising a hollow tube (101) of predetermined length and a coke anchor (102) integral with the external surface (101b) of the hollow tube. 2. Anchoring device (10) according to claim 1, characterized in that the anchoring element (102) is fixed to the external surface of the hollow tube (101) by force assembly, by clipping, screwing or welding or in that the anchoring element (102) is made in one piece with the hollow tube (101). 3. An anchoring device (10) according to claim 1 or 2, characterized in that the anchoring element (102) comprises a fixing part (102a) fixed to the hollow tube and at least one retention element (102b , 102c) forming an acute angle with a longitudinal axis of the hollow tube. 4. Anchoring device (10) according to claim 3, characterized in that said at least one retention element (102b, 102c) is a metal wire. 5. Cyclone (20) for mechanical separation of particles in suspension in a gaseous fluid, in particular intended for a fluid catalytic cracking unit, said cyclone comprising the following elements: a separation enclosure (201), a first pipe (202) opening into the interior of the enclosure for supplying the gaseous fluid loaded with particles, a second pipe (203) intended for the evacuation of the gaseous fluid, located in the upper part of the enclosure and a lower end of which is situated inside the enclosure, a third pipe (204) intended for the evacuation of particles, located in the lower part of the enclosure, in which, l the lower end (203a) of the second pipe has a double wall (30) formed by an internal wall (301) and an external wall (302) defining between them a chamber (303) connected to a pipe (304) supply of gaseous fluid, the chamber (303) being in fluid communication with the interior of the enclosure via a multitude of orifices (305) passing through the external wall (302), characterized in that it comprises a plurality of devices anchor (10) according to any one of claims 1 to 4 each associated with an orifice (305) of the external wall (302), in which each orifice (305) is extended by a hollow tube (101) of an anchoring device extending inside the enclosure (201). 6. Cyclone (20) according to claim 5, characterized in that each hollow tube (101) of an anchoring device (10) extends substantially perpendicular to the surface (306) of the external wall. 7. Cyclone (20) according to claim 5 or 6, characterized in that one end of each hollow tube (101) of an anchoring device is inserted into the orifice (305) which it extends. 8. Cyclone (20) according to any one of claims 5 to 7, characterized in that the external wall (302) of the second pipe is covered with a protective coating (40) of predetermined thickness, each hollow tube (101) projecting from the surface (306) of the external wall of a length sufficient to pass through the thickness of the covering (40) and the anchoring element (102) being fixed on a part of the hollow tube (101 ) located outside the covering (40). 9. Cyclone (20) according to claim 8, characterized in that the protective coating (40) comprises a cellular anchoring structure (401) integral with the external wall (302) whose cells (403) are filled with material composite and in that each orifice (305) extended by a hollow tube (101) is located inside a cell (403). 10. Cyclone (20) according to claim 9, characterized in that the cellular anchor structure (401) is of the honeycomb type with hexagonal cells (403) and in that an orifice (305) extended by 'a hollow tube (101) is located inside a central cell (403) of each group of seven cells in which six cells share a side with the same central cell. 11. Catalytic cracking reactor (50) comprising at least one cyclone (20) according to any one of claims 5 to 10. 12. A fluid catalytic cracking process comprising a reactor (50) according to claim 11: a step of treatment in said reactor of a hydrocarbon feedstock in the presence of catalytic particles in the fluidized state in order to form gaseous effluents, a step of separation of the gaseous effluents produced and the catalytic particles, into which the gaseous effluents produced are introduced and the catalytic particles in at least one cyclone (20) for mechanical separation of the reactor via its first line (202), the solid particles are recovered via its third line (204) and the gaseous effluents via its second line (203) and at during which the chamber (203) of each cyclone (20) is supplied with a gaseous fluid which is introduced into the enclosure (201) of the cyclone via the orifices (305) in the external wall (302) of the second pipe ( 203) and the hollow tubes (101) of the anchoring devices (10). 1/3