DEVICE FOR INJECTING FLUIDS INTO THE FREE AREA OF A ROTATING FLUIDISED BED

Abstract

Device for injecting fluids into the free area of a rotating fluidized bed revolving in a fixed cyclone chamber, and method using this device, comprising a device for tangentially injecting secondary fluids, enabling rotating rings of fluids to be formed in said free area along the side walls of said cyclone chamber, in order to separate from said side walls fluid flows exiting along said side walls and accelerate their rotation velocity, and thus to improve the retention of the solid particles entrained by said exiting fluid flows

Claims

1. A device for injecting secondary fluids into the free area of a rotating fluidized bed in a fixed cyclone chamber, comprising a peripheral wall (4) surrounded by two side walls (3) and (5); a device for supplying fluid (57) through openings (72) distributed along said peripheral wall, in a mainly tangential direction (73); a device for supplying and discharging solid particles; and at least one central tube (7) for discharging the fluids revolving in said cyclone chamber, characterized in that it comprises: a device for supplying secondary fluids (17) and (17.1) through central supply chambers (15) and (15.1) located along each of said side walls (3) and (5), having injection openings (18) and (18.1) distributed around the axis of cylindrical symmetry, enabling said secondary fluids to be injected in a mainly tangential direction (19) and (19.1), in order to form two rotating rings of secondary fluids revolving around said axis of cylindrical symmetry, along said side walls (3) and (5), within said free area, and in that said devices for supplying said secondary fluids enable said secondary fluids to be supplied at a sufficient pressure to make said rotating rings of secondary fluids revolve at a velocity which is greater than the highest rotation velocity of said fluids revolving in cyclone chamber when the latter is in operation without the device for injecting secondary fluid according to the invention.

2. The device as claimed in claim 1, characterized in that said cyclone chamber has a width smaller than its diameter, and in that the distance between the openings (72) for supplying fluid (59) through said peripheral wall is smaller than its mean radius.

3. The device as claimed in claim 1, characterized in that it comprises at least one said central tube for discharging the fluids from each lateral side of the cyclone chamber.

4. The device as claimed in claim 3, characterized in that it comprises at least one separating wall (53), dividing the cyclone chamber into two transverse sections A and B, said separating wall having at least one passage (39) allowing the passage of solid particles entrained by the fluids along said peripheral wall (4) from one said transverse section to the other, and in that it comprises a device for injecting secondary fluids (17.2) and (17.3) along the two sides of said separating wall, in a mainly tangential direction, into said free areas of said transverse sections.

5. The device as claimed in claim 4, characterized in that it comprises said passages (39) located alternately facing the upstream end of an opening (72) on one side, and facing the downstream end of an opening (72) on the other side, of said separating wall.

6. The device as claimed in claim 1, characterized in that at least one said rotating ring of said secondary fluids is formed behind a guide wall (38) before coming into contact with the fluid flows revolving in said free area of the cyclone chamber.

7. The device as claimed in claim 1, characterized in that at least one device for injecting secondary fluid may supply at least 8% of the flow rate of fluids passing through the cyclone chamber, and comprises at least eight said injection openings distributed in said central supply chamber.

8. The device as claimed in claim 1, characterized in that at least one said central tube (7) terminates in a cylindrically symmetric conduit (21), delimited on one side by the flared surface (20) of the end of said central tube (7), and on the other side by the curved surface (26) of a lateral disk (22) closing said central tube (7); said cylindrically symmetric conduit being closed by a circular wall (23) whose inside width (49) is less than the radius of the inlet of said central tube (7), said circular wall (23) having at least two tangential outlet openings (24) for the tangential discharge of the fluids (28) deflected by said cylindrically symmetric conduit.

9. The device as claimed in claim 8, characterized in that the number of said tangential outlet openings (24) is at least four, and in that the sum of their cross sections is at least twice as small as the cross section of said central tube (7).

10. The device as claimed in claim 1, characterized in that a said device for supplying secondary fluids (17) comprises two said contiguous central supply chambers (15.1) and (14), of which one may be used to supply a secondary gas and the other may be used to supply a secondary liquid.

11. The device as claimed in claim 1, characterized in that it comprises at least one tube (80) concentric with a said central tube (7), penetrating into the cyclone chamber and enabling droplets of a liquid to be atomized in said cyclone chamber.

12. The device as claimed in claim 1, characterized in that the device for discharging the solid particles comprises at least one outlet opening (66) in the peripheral wall (4) of the cyclone chamber, surrounded by a decantation tube (12) for the accumulation and discharge of the solid particles (63) under the effect of their inertia and the force of gravity when the device is operating.

13. Use of the device as claimed in claim 1 by a method for processing fluids and solid particles revolving in a cyclone chamber, comprising the separation of said solid particles and said fluids, characterized in that said fluid flows exiting while entraining solid particles along said side walls are separated from said side walls, and their rotation velocity is accelerated by the injection of said secondary fluids along said side walls.

14. A method for processing solid particles and fluids revolving in a cyclone chamber comprising a device for injecting secondary fluid as claimed in claim 1, characterized in that at least one of said secondary fluids reacts with at least one of said fluid flows exiting along a said side wall or separating wall.

15. The method for processing solid particles and fluids revolving in a cyclone chamber as claimed in claim 14, characterized in that it comprises at least two said contiguous central supply chambers, one injecting a secondary liquid and the other injecting a secondary gas, said secondary liquid reacting with the solid particles entrained by a said fluid flow exiting along a said side wall or separating wall.

16. A method for the combustion of carbonaceous matter revolving in a cyclone chamber as claimed in claim 14, characterized in that the fluids injected tangentially through the circular wall (4) do not contain enough oxygen to provide complete combustion of said carbonaceous matter, and in that at least one said secondary fluid supplied by a device according to the invention contains the necessary oxygen to complete the oxidation of said fluid flows exiting along a side wall.

17. A method for processing fluids and solid particles revolving in a cyclone chamber comprising a device for injecting secondary fluid and divided in two transverse section A and B by a separating wall as claimed in claim 4, characterized in that it comprises an endothermic reaction in one section and an exothermic reaction in the other section, and in that at least one of said secondary fluids reacts with at least one of said exiting fluid flows.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG. 1 shows an axial section through an example of a device for injecting secondary fluids along the side walls in the free area of a rotating fluidized bed in a cyclone chamber and a preferred mode of discharge of the fluids revolving in said cyclone chamber.

[0039] FIG. 2 shows an axial section through another example of a device for injecting secondary fluids, in which said injection openings (18) and (18.1) are located on the outside of the cyclone chamber, along the side walls (3) and (5), and with a central fluid discharge tube on each lateral side of said cyclone chamber.

[0040] FIG. 3.a shows a transverse section through the device for injecting secondary fluids, along the cutting line AA of FIG. 2.

[0041] FIG. 3.b shows a transverse section through the device for central discharge of the fluids revolving in the cyclone chamber, along the cutting line BB of FIG. 2.

[0042] FIG. 4 shows an axial section through another example of the devices for injecting secondary fluids, with a lateral rotating disk (50) near said lateral side (5) of a cyclone chamber.

[0043] FIG. 5 shows an axial section through a cyclone chamber divided into two transverse sections A and B by a separating wall (53) having devices for injecting secondary fluids along its two sides and an injection device with two contiguous central supply chambers (15.1) and (14) for injecting different secondary fluids.

DEFINITIONS

[0044] Cyclone chamber, or turbulence chamber, also called vortex chamber, signifies a chamber of circular, generally cylindrical shape, into which one or more fluids are supplied tangentially in order to make solid particles, supplied with said fluids or separately, revolve rapidly inside said chamber. Said fluids are discharged centrally after being separated by centrifugal force from said solid particles, which are discharged separately. A particular example of a cyclone chamber is a simple cyclonic separator, also called a cyclone. Cyclonic separators are usually very elongated, with a length preferably at least three times their diameter; their axis of cylindrical symmetry is usually vertical, and their lower part usually takes the form of a very elongated cone, at the bottom of which the solid particles are collected by gravitation.

[0045] A cyclone chamber with rotating fluidized bed is a cyclone chamber whose peripheral wall is provided with fluid supply openings, allowing the tangential injection of a fluid that passes through a fluidized bed of solid particles suspended in said fluid and revolving along said peripheral wall. The distance between the two side walls is usually small, preferably being less than the diameter, and even less than the radius, of the peripheral wall. The distance between said fluid supply openings is usually less than the radius, and preferably less than half the radius, of the peripheral wall. The recovery of the solid particles preferably takes place along, or near, the peripheral wall.

[0046] Fluid signifies a liquid or a gas, or a mixture thereof. If the cyclone chamber is equipped with a device for atomizing droplets of a liquid, the other fluids are usually gases.

[0047] Fluid flow is the turbulent flow of fluids, that may entrain solid particles, in approximate mean directions, represented purely for guidance by arrowed lines.

[0048] Toroidal vortex or vortex of the toroidal type refers to complex vortices that revolve both around the axis of cylindrical symmetry (1) and around themselves, that is to say around a central circular area (27) of approximately toroidal shape. The sections of these complex vortices are shown schematically by closed curves, which are a highly simplified representation, purely for guidance, of the complex turbulent circulation of the fluids revolving inside cyclone chambers.

[0049] Free area: if a rotating fluidized bed is formed in a cyclone chamber, the solid particles suspended in the fluid that passes through said fluidized bed are concentrated by centrifugal force in a relatively thin area along the peripheral wall, while the central area, called the free area, contains few solid particles, because the Coriolis force increases the centrifugal force here and retains the solid particles toward the peripheral wall.

[0050] The free surface of the rotating fluidized bed, also called the separation surface, is the surface separating the rotating fluidized bed from the free area. In reality, this surface is ill-defined and turbulent. Its section is represented hereafter by a wavy line (98).

[0051] A mainly tangential direction at any point is a direction of which the component tangential to the circumference centered on the axis of cylindrical symmetry (1) and passing through this point is larger than all the other components added together.

DETAILED DESCRIPTION

[0052] FIG. 1 shows an axial section through a cyclone chamber surrounded by a peripheral wall (4) and two side walls (3) and (5), comprising [0053] a device for supplying solid particles (59), that may be entrained by a fluid, via a tube (64) passing through said peripheral wall and a device for discharging solid particles (63) via a tube (12) passing through the side wall (5) at a certain distance from said peripheral wall; [0054] a device for supplying fluid (57) into a supply chamber (69) surrounding said peripheral wall, via tubes (70), enabling said fluids to be injected through a large number of openings (72), represented in the form of longitudinal slots, in a mainly tangential direction (73), that is to say a direction mainly perpendicular to the plane of the figure, in said peripheral wall, enabling a rotating fluidized bed to be formed; [0055] a device for discharging the fluids (25) via a central tube (7) passing through the side wall (3); characterized in that it comprises: [0056] a device for supplying secondary fluids (17) and (17.1) via the tubes (13) and (13.1) through central supply chambers (15) and (15.1), which are arranged along each side wall (3) and (5), one around said central tube (7) and the other around the axis of cylindrical symmetry (1), and are provided with openings, represented by the slots (18) and (18.1) distributed around said axis of cylindrical symmetry and arranged inside the cyclone chamber in this example, for injecting said secondary fluids (17) and (17.1) in mainly tangential directions (19) and (19.1) along said side walls (3) and (5), inside said free area, in order to form rotating rings of fluid behind guide walls (38) and (38.1).

[0057] When the cyclone chamber is in operation without the device for injecting secondary fluids according to the invention, the centrifugal force of the fluids revolving around the axis of cylindrical symmetry (1) concentrates most of the solid particles (63) in the rotating fluidized bed, the separation surface between said bed and said free area being represented by the wavy line (98) along said peripheral wall. Said solid particles (63) are discharged via the tube (12), the distance of which from said peripheral wall determines the mean distance of said free surface and said peripheral wall, and therefore the mean thickness of the rotating fluidized bed.

[0058] The friction along said side walls reduces the rotation velocity of the fluids around the axis of cylindrical symmetry (1), thereby reducing the centrifugal force and promoting the entrainment of solid particles by the fluid flows (30) and (30.1) exiting along said side walls. The centrifugal force generated by the tangential injection (73) of the fluids is higher at a certain distance from the side walls, and may generate a backflow of fluids (31) toward said peripheral wall, thus forming toroidal vortices (32) and (32.1) of fluids revolving both around the axis of cylindrical symmetry (1) and around a circular area (27) in the center of the axial sections of said toroidal vortices. This backflow of fluid reduces the rotation velocity of the fluids and increases the entrainment of the solid particles toward the central outlet by the fluid flows (30) and (30.1) exiting along the side walls.

[0059] When the device according to the invention supplies said secondary fluids at a sufficient pressure, the centrifugal force generated by the high rotation velocity of said rotating rings of secondary fluids generates a backflow of secondary fluids (35) and (35.1) along said side walls, separating said exiting fluid flows (30) and (30.1) from said side walls and accelerating their rotation velocity, a part, called the retained part (33) and (33.1), of these fluid flows containing most of the solid particles entrained by said exiting fluid flows, is retained toward the middle of said peripheral wall. The other part, called the discharged part (34) and (34.1), which has practically ceased to contain solid particles, is discharged toward the central tube (7) while mixing with the secondary fluid. A small part, called the recycled part (9) and (9.1), attracted by the low pressure generated by the centrifugal force of said rotating rings of secondary fluids, is recycled and mixes with the backflow of secondary fluids (35) and (35.1), thus forming a vortex called the secondary toroidal vortex (36) and (36.1), which revolves both around the axis of cylindrical symmetry (1) and around a circular area (27) inside the axial sections of said secondary toroidal vortex. These sections and these vortices vary in shape. They are shown schematically, purely for guidance.

[0060] The rotation velocity of said retained parts of said fluid flows exiting along the side walls, charged with solid particles, is increased by said secondary toroidal vortices, thereby improving the separation of the solid particles from the fluids passing through the rotating fluidized bed.

[0061] It must be possible for the injection pressure of the devices for supplying secondary fluids to be high enough to enable the injection velocity of the secondary fluids to be higher, and preferably at least one and a half times as high, as the highest rotation velocity of the fluids flowing centrally (6) from said cyclone chamber, when it is in operation without the device according to the invention.

[0062] The kinetic moment of rotation transferred by said secondary toroidal vortices to the exiting fluid flows depends on the injection velocity, and therefore on the injection pressure, as well as on the flow rate of said secondary fluids, and therefore on the total cross section of the injection openings (18). These quantities may be chosen according to the requirements and constraints of the method using this device. If the function of the secondary fluids is solely to improve the quality of separation of the fluids and fine solid particles, a low flow rate, with high injection velocities, and therefore a high injection pressure through injection openings with small cross sections, is preferable. However, the transfer of the kinetic moment of rotation becomes inefficient when the differences in velocity are very large. It is therefore desirable to have a flow rate of said secondary fluids that is sufficiently high, preferably in each of said central supply chambers, being at least 5% and preferably at least 8% of the flow rate of the fluids passing through the cyclone chamber.

[0063] When the fluids are discharged via an ordinary central tube (7), the friction along and the tube and at its end reduces the rotation velocity of the fluids and consequently the centrifugal force inside said central tube, thereby reducing the centrifugal pressure drop along the axis of symmetry and generating a pressure gradient toward said cyclone chamber, and consequently a virtually non-rotating central backflow (41), which reduces the rotation velocity of the fluids in said cyclone chamber.

[0064] The secondary toroidal vortices (36) and (36.1) increase the rotation velocity around the axis of symmetry (1) of the centrally exiting fluids (6) in the central tube (7), and therefore also increase the losses due to friction inside the central tube (7) and the undesirable central backflow (41) toward said cyclone chamber. In order to reduce these losses of rotation velocity, the central tube (7) for discharging the centrally exiting fluids (6) is short, its length preferably being less than the diameter of its inlet. Its outer end is flared and terminates in a cylindrically symmetric conduit (21), delimited on one side by the flared surface (20) of said central tube and on the other side by the curved central surface (26) of a lateral disk (22) closing the axial outlet of said central tube.

[0065] Said cylindrically symmetric conduit (21), for deflecting the centrally exiting fluids (6), called deflected fluids (28), without preventing their rotation around the axis of symmetry (1), by converting their axial velocity (29) to radial velocity, terminates in a circular wall (23), comprising at least two and preferably at least six tangential outlet openings (24) for discharging the fluids (25) in a mainly tangential direction through said circular wall (23). Said curved surface (26) has a conical profile, with a rounded tip (40) and flaring at the base, chosen so that the cross sections of said cylindrically symmetric conduit (21) are smaller than the inlet of said central tube (7), to progressively deflect the exiting fluids without slowing them.

[0066] The inside width (49) of said circular wall (23) is less than the radius, and preferably less than half the radius, of the inlet of said central tube (7), so that the radial outlet velocity of the discharged fluids (25) through said circular wall (23) is relatively high. The sum of the cross sections of said tangential outlet openings (24) is smaller than half the inlet cross section of the central tube (7), and preferably small enough for the outlet velocity of said discharged fluids (25) to be higher than the total mean velocity of the centrally exiting fluids (6) at the inlet of the central tube (7).

[0067] Said tip (40) of said curved surface penetrates into said central tube (7), preferably beyond the inlet of said central tube (7), in order to push the initiation of the central backflow (41) back into the cyclone chamber. Said central backflow (41), virtually non-rotating, is drawn in and recycled (9.1) by the low pressure generated by said secondary toroidal vortex (36.1) which transfers some of its kinetic moment of rotation to it before being discharged via the central tube (7). This transfer of kinetic moment of rotation reduces the negative effect of said central backflow on the rotation velocity of the fluids inside the cyclone chamber.

[0068] The central discharge of the fluids according to the preferred embodiment of the invention, described in this example, thus makes it possible to reduce and even reverse the negative effect of the central fluid discharge tube on the rotation velocity of the fluids inside said cyclone.

[0069] The static pressure drop of the fluids discharged (25) at high velocity may be partially recovered downstream of the tangential outlet openings (24), with the aid of conduits with flared outlets (42), which enable some of their dynamic pressure to be recovered, as shown in FIG. 3.b.

[0070] FIG. 2 shows an axial section through another example of devices for injecting secondary fluids, in which said injection openings (18) and (18.1) are located on the outside of the cyclone chamber, along the side walls (3) and (5), and with a central fluid discharge tube (7) and (7.1) on each lateral side of said cyclone chamber. In this example, the solid particles (59) are supplied through the tube (64) that passes through the middle of the peripheral wall (4). They are entrained in a rotary movement by the fluid (57) injected in a mainly tangential direction (73) into the cyclone chamber. They are added to the solid particles retained in the middle of the cyclone chamber, and are pushed axially by centrifugal force toward the side walls (3) and (5).

[0071] The heavy solid particles are discharged via two decantation tubes (91) located near the side walls (3) and (5). Rotary valves or pairs of valves opening alternately, not shown in the figure, enable the pressure differences to be absorbed without entraining the fluids revolving in the cyclone chamber, and enable the flow rate of the heavy solid particles to be controlled.

[0072] The other solid particles, mainly the finest or lightest ones, are discharged via the outlet tubes (12) which determine the thickness of the rotating fluidized bed whose free surface is represented by the wavy line (98). Said other solid particles and the fluid flow that entrains them in the tubes (12) may be separated by a suitable device such as a cyclone or filter.

[0073] The injection openings (18) and (18.1) of the devices for supplying the secondary fluids (17) and (17.1) are located, in this example, outside the cyclone chamber. Said rotating rings of secondary fluids, formed behind said side walls, penetrate into the cyclone chamber through annular openings (11) and (11.1), which are preferably narrow, between said central tubes (7) and (7.1) and said side walls (3) and (5), which act as the guide walls (38) and (38.1) of FIG. 1. This separation enables said rotating rings of secondary fluids to be made uniform before coming into contact with the fluids revolving in the cyclone chamber, to avoid generating undesirable turbulence.

[0074] The second central tube (7.1) for discharging the fluids is relatively small in this example, so that it mainly discharges the central backflow (41) originating from the virtually non-rotating area that lies along the axis of cylindrical symmetry (1). This central tube (7.1) may be similar to the central tube (7), as in FIG. 5.

[0075] FIG. 3.a shows a transverse section, along the cutting line AA of FIG. 2, through the device for injecting secondary fluids (17) which are supplied under pressure via the supply tubes (13) into the central supply chamber (15) and injected through eight injection openings (18), delimited by eight successive plates (48). These secondary fluids, injected in a mainly tangential direction (19) at high velocity around the central tube (7), form a rotating ring (44) of secondary fluid between said successive plates (48) and said central tube (7) outside the side wall (3), before penetrating into the cyclone chamber. Said rotating ring is represented by the numbers (44.1), (44.2) and (44.3) respectively when it relates to the secondary fluids (17.1), (17.2) and (17.3).

[0076] The centrally exiting fluid flows (6) revolve inside the central tube (7) around the section of the tip (40) of said curved surface of said lateral disk. They are discharged by two outlet tubes (43), which are shown for guidance in the background.

[0077] FIG. 3.b shows a transverse section, along the cutting line BB of FIG. 2, through the device for central discharge of the fluids, according to a preferred embodiment of the invention. The deflected fluids (28) revolve around the curved surface (26) inside the cylindrically symmetric conduit (21), and are discharged at high velocity through six tangential outlet openings (24) with small cross sections, connected to two manifolds (89) by flared conduits (42), whose outlet cross sections are preferably at least three times larger than the cross sections of the tangential outlets (24), in order to recover some of the dynamic pressure of the discharged fluids (25). The decelerated fluids (76) are discharged via the two tubes (43).

[0078] If the cross sections of the tangential outlet openings (24) are small enough, this device makes it possible to maintain, and even increase, the rotation velocity of the deflected fluids (28) and therefore of the centrally exiting fluids (6) in the central tube (7), so as to have a positive effect on the rotation velocity of the fluids in said cyclone chamber.

[0079] The tubes (13) for supplying secondary fluids (17) are shown, for guidance, in the background.

[0080] FIG. 4 shows another example of a cyclone chamber equipped with the devices for injecting secondary fluids, according to the invention, with a rotating lateral disk (50), near the side wall (5), guiding the backflow of secondary fluid (35.1) and supported by a device symbolized by a rotating shaft (51) and ball bearings (52) held by a fixes support (93), enabling said rotating disk to be revolved at a sufficient velocity to accelerate the rotation velocity of the fluids revolving in the cyclone chamber near the rotating disk. The greater centrifugal force generated by the rotating disk also increases the intensity of the toroidal vortex (36.1), which retains the solid particles entrained by the exiting fluid flows (30.1) along the side wall (5). The diameter and rotation velocity of said rotating disk are chosen according to the requirements of the method using this device.

[0081] In this example, a tube (64) supplies solid particles (59) through said peripheral wall, these particles preferably being tangentially entrained by a fluid, near the side wall (5). The fluids (57.1) and (57.2), supplied via the tubes (70) into the supply chambers (69.1) and (69.2) surrounding the cyclone chamber, are injected tangentially via injection openings, such as longitudinal injection slots (72), to make said fluids and said solid particles (63) revolve in the cyclone chamber.

[0082] The coarser solid particles (63.1) are discharged through an outlet opening (66) along the circular wall (4) via a decantation tube (91), preferably located near the other side wall (3), and the lighter particles (63) are preferably discharged via a tube (12) through the side wall (3).

[0083] In this particular example, the central tube (7), passing through the side wall (3) opposite said lateral rotating disk (50), surrounds a concentric tube (80) which penetrates into the cyclone chamber near the lateral rotating disk (50). It may be used for centrally supplying a fluid (86), which may, for example, be atomized in the form of droplets of a liquid used, for example, for cooling the fluids or for impregnating the solid particles revolving in the cyclone chamber.

[0084] This example also comprises an annular separating wall (88) which may be used to reduce the axial flow of the solid particles revolving along the circular wall (4) between said annular separating wall and the side walls (3) and (5), according to the requirements of the method using this device.

[0085] FIG. 5 shows an axial section through another example of an approximately symmetrical cyclone chamber, divided into two transverse sections A and B by a separating wall (53), and having devices for injecting secondary fluids along the two sides of said separating wall.

[0086] The fluids, (57.1) to (57.3), are supplied through three supply chambers, (69.1) to (69.3), surrounding the cyclone chamber. The fluid (57.2) is injected through openings (72) distributed to face the periphery of said separating wall (53), which is located at a short distance from said peripheral wall, leaving a passage (39), which is preferably narrow, allowing the transfer of the solid particles from one said transverse section to the other. Annular separating walls (88.1) and (88.2) may guide the fluid (57.2) on either side of said separating wall, in order to strip the flow of solid particles, transferred from one transverse section to the other, from the fluids that entrain them.

[0087] In this example, the passage (39) covers the whole periphery of said separating wall and the openings (72) for supplying the fluid (69.2) are aligned along said passage (39). The flow of the solid particles between the two transverse sections is generated by the turbulence. This flow may be increased by using multiple passages (39), arranged alternately facing the upstream end of an opening (72) on one side, and facing the downstream end of an opening (72) on the other side, of said separating wall.

[0088] The solid particles (61) are supplied via a supply tube (60) passing through the side wall (5), and the solid particles (63) are discharged via a tube (12) passing through the side wall (3) at a distance from the peripheral wall (4) which determines the mean level of the free surface (98.1) of the rotating fluidized bed revolving in said transverse section A. The mean of the free surface (98.2) of the rotating fluidized bed revolving in said transverse section B is determined by the pressure difference between the free areas of the two transverse sections. A suitable device for controlling the pressure differences, not shown, should enable the free surface (98.2) to be kept at the desired mean level.

[0089] The secondary fluids (17.2) and (17.3) are supplied via the tubes (13.2) and (13.3) which are concentric with the central tubes (7) and (7.1), and are injected via the openings (18.2) and (18.3) in mainly tangential directions (19.2) and (19.3) behind the guide walls (38.2) and (38.3), in order to form rotating rings of secondary fluids that accelerate the rotation velocity and push back the exiting fluid flows (30.2) and (30.3), which entrain solid particles along the surfaces of said separating wall (53), in order to retain toward said peripheral wall said retained parts (33.2) and (33.3) which contain most of the solid particles entrained by said exiting fluid flows (30.2) et (30.3). Said discharged parts (34.2) and (34.3) have practically ceased to contain any solid particles.

[0090] In this example, the device for supplying secondary fluids around the central tube (7.1) passing through the side wall (5) comprises a chamber (14) contiguous to the central supply chamber (15.1), allowing the supply of a different secondary fluid (77), one of which may be gaseous and the other liquid, in order to atomize said liquid inside the cyclone chamber. Said liquid may react chemically and/or physically with the exiting fluids (30.1), which are usually gases, and/or the solid particles that are entrained by said exiting fluids before being retained. The other three devices for supplying secondary fluids may also have such a device in the form of a contiguous central supply chamber.

[0091] The various devices and combinations of devices in the examples described above may be used by methods for processing solid particles reacting in contact with the fluids revolving in a cyclone chamber, such as combustion, gasification, pyrolysis, roasting, drying, encapsulation, surface treatment, impregnation, extraction of volatiles, oxidation and reduction, etc., of solid particles, and for methods for processing fluids revolving in a cyclone chamber in contact with the solid particles which may be catalysts and/or reactants, for example cracking, disproportionation, dehydrogenation, oxidation, oxidation and reduction, polymerization, etc., of fluids revolving in the cyclone chamber, said processing methods comprising the separation of said solid particles and said fluids.

[0092] The use of the device for injecting secondary air and for centrally discharging fluids according to the invention by said methods for processing solid particles and fluids revolving in a cyclone chamber is characterized in that the injection of secondary fluids makes it possible to improve the separation of the solid particles and the exiting fluids, by increasing the rotation velocity of the fluids in the free area of the cyclone chamber, mainly along the side walls and separating walls, without significantly accelerating rotation velocity of said rotating fluidized bed.

[0093] This device is therefore particularly useful for methods in which the desired ratio between the hourly mass flow rate of the fluids and the mass of the rotating fluidized bed is too small to allow a sufficient transfer of kinetic moment of rotation to make the rotating fluidized bed revolve at the necessary velocity to provide good separation between the fluids and the solids, or when the mechanical or physical constraints, for example the abrasion or the sensitivity of the solid particles to friction limit the rotation velocity of said solid particles along said peripheral wall, as in the example of the polymerization of polyethylene powders which is sensitive to the formation of angel hair.

[0094] The invention also relates to methods using the devices for injecting secondary fluids according to the invention, characterized in that at least one of said secondary fluids cools, or reacts chemically with, at least one of said exiting fluid flows that have reacted with the solid particles of the fluidized bed revolving in the cyclone chamber.

[0095] For example, gases resulting from gasification, or from the pyrolysis or roasting or extraction of volatiles from solid particles in suspension in the rotating fluidized bed, may be cooled quickly by the atomization of secondary liquids supplied by contiguous chambers as described in FIG. 5, to avoid undesirable secondary reactions.

[0096] FIG. 2 illustrates an example of a particular two-step method of combustion of carbonaceous, solid or fluid materials, such as coal dust or shredded organic waste, using oxygen-enriched gas, for example, characterized in that partial combustion is initially carried out in the rotating fluidized bed of said cyclone chamber, after which the oxygen of said secondary fluid injected by the injection device according to the invention terminates the combustion of the exiting gas flows (30) and (30.1).

[0097] The use of oxygen-enriched gas makes it possible to reduce the cost of recovering undesirable products such as CO.sub.2. This combustion may be very rapid, while generating very high temperatures contributing to slag formation. Cyclone chambers with rotating fluidized beds enable virtually explosive combustion to be controlled because of the very high ratio of the mass flow rates of the gases to the mass of the solids presents in the rotating fluidized bed, which may be greater than 1000 per hour, owing to a centrifugal force which is higher by more than an order of magnitude than the force of gravity, and also owing to the large surface and thinness of the rotating fluidized bed.

[0098] For guidance, a 1 m.sup.3 cyclone chamber may contain a rotating fluidized bed containing about 100 kg of powder, and may have an hourly mass flow rate of pressurized gas of more than 200 tonnes per hour passing through it, enabling carbon to be partially burnt at about 10 kg per second, with a mixture by mass of about vapor and pure oxygen. If the rotating fluidized bed contains 20% coal dust, the remainder being ashes or inert, oxidizing or catalytic powders, the partial combustion time for the coal dust is about two seconds. The combustion of gases rich in CO may be completed at the time of their exit from the cyclone chamber by the oxygen contained in the secondary fluids, which are injected at high velocity into the free area of the cyclone chamber.

[0099] Carbonaceous matter (59) may, for example, be supplied in suspension, or dissolved in a liquid, for example water, using a high-pressure pump. The mixture may be preheated to a temperature allowing some of the liquid to vaporize, to generate a mixture of solids, liquid and vapor (59) which may be injected tangentially, at high velocity, into the cyclone chamber via the tube (64). A gas containing an insufficient quantity of oxygen to provide complete combustion of all the carbon contained in said carbonaceous matter is supplied by the supply chambers (69.1) and (69.2) into the cyclone chamber which is preheated to a sufficient temperature to burn the carbon, producing a mixture of CO and CO.sub.2. The flow rates may be adjusted to obtain the desired temperature, which is sufficiently high for rapid combustion and sufficiently low to avoid slag formation, being about 650 C. for example, in the peripheral part of the cyclone chamber.

[0100] The heavy ashes (63) may be discharged through said peripheral wall via the decantation tubes (91). The fine or light ashes (87) are discharged via the lateral outlets (12), or are entrained along the side walls (3) and (5) by the exiting fluid flows (30) and (30.1) and retained by the backflows of secondary fluids (35) and (35.1), which form the secondary toroidal vortices (36) and (36.1), toward said peripheral wall.

[0101] The oxygen contained in the secondary fluids (17) and (17.1) may terminate the oxidation of the partially oxidized gases in the central part of the cyclone chamber and in the central tubes, without allowing the heat evolved by this post-combustion to overheat the ashes formed along the circular wall. The light ashes that have been retained by the secondary vortex may be very hot and may form, in the peripheral part of the cyclone chamber, small clusters that may be discharged via the decantation tubes (91).

[0102] Annular separating walls (88), as illustrated in FIGS. 4 and 5, may be added to separate the rotating fluidized bed into a plurality of sections through which fluids having different compositions and/or temperatures pass. For example, water vapor may be injected around the decantation tubes to strip the heavy particles before discharging them.

[0103] The small size of such a cyclone chamber allows operation at very high pressure, and the post-combustion makes it possible to reach the temperatures required for the complete combustion of the undesirable components and the efficient recovery of the combustion energy. The use of pure oxygen and carbonaceous matter in suspension, or dissolved in water, makes it possible to control the temperature of the rotating fluidized bed and to recover the CO.sub.2 at lower cost. Finally, the quality of the separation of the burnt gases and solid particles, due to the central injection of very fast secondary gases, generating a centrifugal force that may be greater by several orders of magnitude than gravity in the central part of the cyclone chamber, may retain the fine solid particles to a sufficient extent to allow a turbine to be supplied directly.

[0104] The device described by FIG. 4, with or without a rotating disk, may be used, for example, for the methods of encapsulation, surface treatment or impregnation. The encapsulation, surface treatment or impregnation liquid (86) may be atomized by the tube (80) onto the rotating disk (50) that revolves at high velocity, or may be sent by means of an atomizer directly into the free area of the cyclone chamber. The liquid may also be injected via atomizers passing through a side wall or the peripheral wall, or by means of a contiguous central supply chamber (14), illustrated in FIG. 5.

[0105] The device according to the invention also relates to methods for processing solid particles such as surface treatment, encapsulation and impregnation, and is characterized in that it comprises at least one contiguous central supply chamber for supplying a secondary liquid that reacts with the solid particles entrained by a said fluid flow exiting along a said side wall or separating wall.

[0106] The centrifugal force pushes the droplets of liquid toward the peripheral wall where they may react with the solid particles in suspension in said rotating fluidized bed. The solid particles then migrate toward the side wall (3), on the other side of the cyclone chamber, along the circular wall (4) through which the gases (57.1) and (57.2) pass. The composition and temperature of these gases are chosen according to the requirements of the method. For example, the gas (57.2) may be cold to retard drying, in order to make a surface treatment uniform, or may be hot in order to accelerate the setting of the surface treatment as the treatment progresses. The solid particles are then discharged via the tube (12) or the decantation tube (91). An annular wall (88) may increase the dwell time of the solid particles in the transverse section on the right of the cyclone chamber.

[0107] The device according to the invention also relates to methods for processing fluids and solid particles comprising the alternating processing of said solid particles in a cyclone chamber divided into two transverse sections according to one of the particular embodiments of the invention, and is characterized in that it comprises an endothermic reaction in one section and an exothermic reaction in the other section, and in that at least one of said secondary fluids reacts with at least one of said exiting fluid flows.

[0108] The device described by FIG. 5 illustrates the methods of alternating processing, for example an oxidation step that regenerates catalytic solid particles and/or generates the heat required for the second step, for example catalytic cracking or gasification or dehydrogenation, which absorbs heat. The solid particles are supplied through the side wall (5) via the tube (68) and are discharged on the other lateral side via the tube (12). They form a rotating fluidized bed through which the fluid (57.3), hydrocarbons for example, passes from one side, while the fluid (57.1), air for example, passes through it from the other side. A separating fluid (57.2), water vapor for example, may be used to strip the solid particles of the fluids that they entrain with them when they pass from one side to the other.

[0109] When the device is in operation, the solid particles form a rotating fluidized bed and flow rapidly from one side of the bed to the other, while transferring their heat and their kinetic moment of rotation, thereby contributing to a substantial reduction in the differences between the temperatures and rotation velocities on the two sides of the rotating fluidized bed. On the other hand, the fluids pass through the rotating fluidized bed very rapidly and are discharged separately via the central discharge device located on their side, without mixing with one another, the separating wall providing suitable separation. The separation fluid (57.2) may be used to improve this separation by preventing the transfer of the other fluids from one side to the other. It may also be injected at very high velocity to increase the rotation velocity of the rotating fluidized bed.

[0110] For example, for a gasification method, the fluids (57.3) and (57.2) may be water vapor and the fluid (57.1) may be air. The carbonaceous particles are introduced through the side wall (5) with other solid particles, such as dolomite, that serve to improve the heat transfers and may also serve to catalyze or prevent the formation of slag.

[0111] The rotating fluidized bed is heated by the combustion of the residual carbonaceous matter in contact with the air in section A of the cyclone chamber. This heat is transferred by the rotating fluidized bed to section B where the carbonaceous particles are introduced, in order to reach the necessary temperature for gasification.

[0112] Another example of a method that may use a device similar to that described in FIG. 5 is the dehydrogenation of hydrocarbons such as ethane or propane to produce olefins, and the dehydrogenation of ethylbenzene to produce styrene by processes of oxidation and reduction, or oxidation, of carbonaceous matter using catalysts containing metallic oxides which are reduced in one section of the cyclone chamber and reoxidized in the other section, through which an oxidizing fluid passes. The heat produced by the oxidation in said other section is transferred by the rotating fluidized bed into the part where the oxygen transfer, which is an endothermic reaction, takes place.