FR3063233A1 - DEVICE WITH REMOVABLE CERAMIC ELEMENT FOR THE INTRODUCTION OF A LIQUID INSIDE AN INJECTOR, AND CORRESPONDING INJECTOR. - Google Patents

Abstract

The invention relates to a device for introducing (30) a liquid inside an injector shaped to atomize said liquid into droplets by means of a gas, said introduction device comprising an orifice (32) on which traversing through, characterized in that it comprises: - an inner portion (34) of ceramic material, an inner surface (34i) defines said through-hole (32) over its entire length, - an outer portion (36) of metal material surrounding at least part of the inner part (34), - the outer and inner parts respectively having an inner surface (36i) and an outer surface (34e) of complementary shapes provided with fastening elements (40, 42) cooperating to releasably secure said inner and outer portions. The invention also relates to a liquid injector equipped with said introduction device.

Description

063 233

51529 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(to be used only for reproduction orders)

©) National registration number

COURBEVOIE © Int Cl ⁸ : B 01 J 19/26 (2017.01), B 01 J 8/08, 19/02, B 05 B 1/00, C 10 G 11/18

A1 PATENT APPLICATION

©) Date of filing: 27.02.17. (© Priority: © Applicant (s): TOTAL REFINAGE CHIMIE— FR. @ Inventor (s): LESAGE ROMAIN. ©) Date of public availability of the request: 31.08.18 Bulletin 18/35. ©) List of documents cited in the preliminary search report: See the end of this booklet (© References to other related national documents: ® Holder (s): TOTAL CHEMICAL REFINING. ©) Extension request (s): © Agent (s): CABINET FEDIT LORIOT.

DEVICE WITH REMOVABLE CERAMIC ELEMENT FOR THE INTRODUCTION OF A LIQUID INSIDE AN INJECTOR, AND CORRESPONDING INJECTOR.

FR 3 063 233 - A1

Q /) The invention relates to a device for introducing a liquid (30) inside an injector shaped to atomize said liquid into droplets by means of a gas, said introduction device comprising an orifice ( 32) crossing it right through, characterized in that it comprises:

an internal part (34) of ceramic material, an internal surface (34i) of which defines said through orifice (32) over its entire length,

an external part (36) made of metallic material at least partially surrounding the internal part (34),

- The external and internal parts respectively having an internal surface (36i) and an external surface (34e) of complementary shapes provided with fixing elements (40, 42) cooperating to detachably fix said internal and external parts.

The invention also relates to a liquid injector equipped with said introduction device.

DEVICE WITH REMOVABLE CERAMIC ELEMENT FOR THE INTRODUCTION OF A LIQUID INSIDE AN INJECTOR,

AND CORRESPONDING INJECTOR

The invention relates to a device for introducing a liquid inside a liquid injector, in particular a charge injector of a fluid catalytic cracking unit (FCC "Fluid Catalytic Cracking" in English). This introducer has a removable ceramic element.

The charge of an FCC unit can be charged with solid particles, especially in the case of recycling of "slurry" produced by the unit. This slurry contains fines from the FCC unit.

The advantage of recycling slurry is multiple: help with the heat balance, or elimination of slurry. This practice may be at the origin of the erosion of the charge injectors, in particular if the slurry recycle is durable, and more particularly of the charge admission orifice inside the injectors, in particular of impactor or double impact type.

This erosion can be limited by the use of injectors made entirely of ceramic, as described in document W02016016090-A1. Although these injectors can be produced in several parts assembled together, it may prove difficult, if not impossible, to separate them in order to change them, in particular depending on the nature of their assembly: it is then necessary to completely change the injector, in particular when it is necessary to modify one of the parts according to the operating conditions of the process implemented. The use of these injectors in an existing unit also requires the replacement of the complete injectors of this unit.

There is therefore a need for an erosion-resistant liquid intake orifice which can be easily installed on the charge injectors, in particular of the impactor type, without having to replace the complete injector with a ceramic model.

To this end, the object of the invention relates to a device for introducing a liquid inside an injector shaped to atomize said liquid into droplets by means of a gas, said introduction device comprising a orifice passing right through it, characterized in that it comprises:

an internal part made of ceramic material, an internal surface of which defines said through orifice over its entire length,

an external part made of metallic material at least partially surrounding the internal part,

- the external and internal parts respectively having an internal surface and an external surface of complementary shapes allowing a displacement of the internal part with respect to the external part in a direction parallel to an axis of the through passage, said internal and external surfaces being provided with fasteners cooperating to reversibly fix said internal and external parts.

In other words, the fastening elements ensure a non-final (removable) fixing of the internal and external parts. This makes it possible to easily change the internal part defining the through hole, making it possible to adapt the latter to the operating conditions of the process in which the injector provided with the introduction device is to be used.

Advantageously, the external surface of the internal part and the internal surface of the external part can be surfaces of revolution having an axis of revolution coincident or parallel to the tax of the through orifice. This facilitates the production of the internal and external parts and simplifies the design of the fastening elements.

The fastening elements can then comprise lugs or notches cooperating respectively with grooves or ribs of suitable shape to allow the displacement of the external and internal parts between a state of fixation and a state released following translational movements in a parallel direction. to Tax of revolution and rotation around Tax of revolution.

The fixing of the internal and external parts and their disassembly can then be carried out in a very simple manner by successive movements of translation and rotation, respectively of rotation and translation. In its simplest design, this type of attachment can then be similar to a bayonet type attachment. In a more complex design, this type of attachment can provide a "polarizing" function during assembly, or even prohibit the assembly of an unsuitable internal part.

Whatever the shape of the fastening elements of the internal and external parts, an elastic element can be arranged between the internal and external parts so as to be compressed in a direction parallel to the axis of the through orifice when the internal and external are fixed. This can improve the fixation between the inner and outer parts. This elastic element may be a spring, a compressible polymeric material, or the like.

The external part may have an external surface intended to be fixed, in particular definitively, to an orifice of the injector receiving the introduction device according to the invention.

However, advantageously, an external surface of the external part can comprise fixing elements shaped to ensure non-definitive fixing to this orifice. This can make it possible to completely separate the introducer from the charge injector, for example to replace or modify it.

For example, these fasteners may include a thread.

The external part is made of metallic material, for example a metal or an alloy, preferably a stainless steel, or a carbon steel.

The ceramic material of the internal part of the introduction device according to the invention can be chosen from silicon carbide SiC, boron carbide ELC, silicon nitride S13N4, aluminum nitride AIN, boron nitride BN , alumina AI2O3, or mixtures thereof.

Advantageously, the ceramic material is silicon carbide SiC or comprises silicon carbide SiC, preferably in a majority amount, for example in a content of 60% to 99.9% by weight. Silicon carbide has the advantage of having good mechanical and physical properties at a reasonable manufacturing cost.

As a variant or optionally in combination, the ceramic material may comprise a ceramic matrix chosen from silicon carbide SiC, boron carbide B4C, silicon nitride S13N4, aluminum nitride AIN, boron nitride BN, alumina

AI2O3, or mixtures thereof, ceramic matrix into which are incorporated fibers selected from carbon fibers and ceramic fibers, or mixtures thereof.

The ceramic material is then a composite material. Such a composite material can be advantageous for injectors subjected to stretching and shearing stresses. In particular, the fibers can be arranged in a random (pseudo-isotropic) or anisotropic manner. Anisotropic distribution of the fibers can be advantageous in particular zones, for example the end zones intended to be assembled with another material or with another part of the same material or in the case of zones subjected to a stretching stress / significant shear. When present, these fibers can represent from 0.1 to 10% by weight of the composite material.

The carbon fibers can be carbon fibers with the graphitic planes oriented along the fiber.

The ceramic fibers can be chosen from crystalline alumina fibers, mullite fibers (3AI2O3, 2S1O2), crystalline or amorphous silicon carbide fibers, zirconia fibers, silica-alumina fibers, or mixtures of these.

Preferably, the composite ceramic material comprises a matrix of silicon carbide SiC, comprising fibers of the aforementioned type. Preferably, the fibers are silicon carbide fibers.

Advantageously and in a nonlimiting manner, the ceramic material can be a sintered ceramic material. This can in particular facilitate the production of the internal part of the introduction device.

In this case, the internal part of the introduction device can be formed for example by molding or by extrusion, followed by firing, under conventional operating conditions adapted to the type of ceramic produced. The cooking step may be preceded by a drying step.

Advantageously, the internal and / or external walls of the internal part of the introduction device can be smooth, in other words, they can have a low surface roughness. Such smooth walls can make it possible to increase the speeds in service inside the internal part of the introducer.

Such a smooth wall can be obtained when the ceramic material is a sintered ceramic material.

Advantageously and in a nonlimiting manner, the internal part of the introduction device can be obtained from a relatively fine sintering powder, for example with an average grain diameter less than or equal to 500 nm, which can lead to relatively smooth surfaces.

Alternatively or in addition, the internal part of the introduction device can be obtained by adding to the main material, for example SiC, an additive, chosen from boron B, silicon Si and carbon C, or mixtures thereof, for example in a proportion varying from 0.3% to 2% by weight. In the case of an SiC material obtained by powder sintering, such an addition of additive can make it possible to reduce the porosity and consequently the roughness.

Advantageously and without limitation, the additive can comprise a mixture of boron B, silicon Si and carbon C. It can thus form additional SiC, which clogs the pores and thus reduces roughness.

Alternatively or in addition, it is possible for example to provide an additional SiC deposition step by chemical vapor deposition or CVD (from the English "Chemical Vapor Deposition").

The invention also relates to a liquid injector shaped to atomize a liquid into droplets by means of a gas, comprising a hollow body having:

at least a first gas inlet port intended to be connected to a gas supply conduit, at least a second liquid inlet port intended to be connected to a liquid supply conduit, at least a contact chamber formed inside the hollow body and into which open said inlet orifices, at least one outlet orifice for the evacuation of the atomized liquid from the hollow body.

The second inlet orifice may or may not protrude inside the contact chamber from an internal wall thereof.

According to the invention, said at least one second inlet orifice is provided with an introduction device according to the invention.

It is thus possible to modify the device for introducing the charge inside the injector by replacing its internal part. When the fasteners fixing the introduction device to the injector are removable, the entire introduction device can be replaced.

In particular, said at least one second inlet orifice may be provided with fastening elements cooperating with fastening elements of an external surface of the external part of said introduction device.

The charge injector can be an “impact” type injector. It can then be an impactor injector which comprises a single second inlet port with a radial axis and a target located inside the body opposite the second inlet port. It can also be a double-impact injector, which comprises at least two second radial-axis inlet orifices arranged so that the liquids leaving said orifices come into contact inside the body.

The invention finally relates to a reactor provided with at least one injector according to the invention. This reactor is for example a tubular type reactor with upward or downward flow intended to be used in a fluid catalytic cracking unit.

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

Figure 1 illustrates a schematic sectional representation of an injector according to one embodiment;

Figure 2 illustrates a schematic sectional representation of an injector according to another embodiment;

Figure 3 shows a sectional view of an introduction device according to one embodiment;

Figure 4 shows a sectional view of an introduction device according to another embodiment;

5 shows a sectional view of Figure 3 along the line A-A.

FIG. 1 schematically represents an injector 10 which has a hollow body 12, here cylindrical.

This hollow body 12 has:

a first gas inlet orifice 14, intended to be connected to a gas supply conduit, a second liquid inlet orifice 16, intended to be connected to a liquid supply conduit, an orifice outlet 18 for the evacuation of the atomized liquid, a contact chamber 20 formed inside the hollow body 12 and into which the inlet orifices 14, 16 open.

The injector 10 shown in FIG. 1 is commonly called of the “impactor” type. Here, the contact chamber 20 is in the form of a rectilinear internal pipe connecting the first inlet orifice 14 to the outlet orifice 18 in an axial direction of said body. The contact chamber 20 has a substantially constant internal diameter.

The injector notably comprises a target 22 extending from an internal wall 24 of the contact chamber 20 opposite the orifice 16 for introducing the liquid and through the gas passage.

The liquid is projected against the target 22 as soon as it enters the contact chamber 20 through the orifice 16. The jet of liquid explodes and is carried in the form of droplets by a stream of atomizing gas introduced through the orifice 14 to high speed. The atomization of the liquid in this type of injector 10 is carried out in two stages. A first part of the atomization occurs at the level of the target 22 by a burst of the jet of liquid. The second part of the atomization occurs at the outlet 18 of reduced diameter, where the narrowing of the diameter accelerates the fluids.

FIG. 2 represents another type of injector 110. The latter comprises a hollow body 112, which has:

a first gas inlet port 114, intended to be connected to a gas supply conduit, two second liquid inlet ports 116, 117, intended to be connected to one or two gas supply conduits liquid, an outlet orifice 118 for discharging the atomized liquid, a contact chamber 120 formed inside the hollow body 112 and into which the inlet orifices 114, 116, 117 open.

The injector 110 is also of the "impactor" type, but the jet of liquid does not impact on a target but on another jet of liquid.

Thus, the second orifices 116, 118 are arranged opposite one another so that the jets of liquid leaving them impact inside the contact chamber 120, substantially facing the orifice d gas inlet 114. In this embodiment, the contact chamber 120 is also in the form of a rectilinear internal pipe connecting the first inlet port 114 to the outlet port 118 in an axial direction of said body , with a substantially constant internal diameter.

The invention is not however limited to a particular type of liquid injector, provided that this injector receives a liquid to be atomized via one or more orifices.

According to the invention, the second orifice 16 of the injector 10 or the second orifices 116, 117 of the injector 110 are provided with a device 30 for introducing the liquid. These introduction devices 30 are represented diagrammatically by dotted lines in FIGS. 1 and 2. They are described in more detail with reference to FIGS. 3 to

5.

In the embodiment shown in Figure 3, the introduction device 30 comprises an orifice 32 passing through it right through and intended for the passage of the liquid to be introduced into the injector for atomization.

This introduction device 30 includes:

an internal part 34 made of ceramic material,

an external part 36 made of metallic material at least partly surrounding the internal part 34.

The materials that can be used are those previously described.

The internal part 34 has an internal surface 34i and an external surface 34e. The internal surface 34i defines the through hole 32 over its entire length.

The external part 36 has an internal surface 36i and an external surface 36e. The external surface 36e is here provided with first fastening elements 38 shaped to cooperate with fastening elements of a second orifice 16, respectively 116, 117 of the injectors 10 and 110. Note that this external surface 36e could be integral with the second orifice. In particular, the external part could be part of the opening.

The internal surface 36i of the external part 36 and the external surface 34e of the internal part 34 are furthermore of complementary shapes allowing a displacement of the internal part 34 relative to the external part in a direction parallel to the axis X of the through hole 32. These internal 36i and external 34e surfaces are provided with second fastening elements cooperating to reversibly fix the internal parts 34 and external 36. It is thus possible to separate these parts in order to change one or the other of the parties.

In the example shown in FIG. 3, the external surface 34e of the internal part 34 and the internal surface 36i of the external part 36 are surfaces of revolution having an axis of revolution coincident with the axis X of the through orifice 32. The external surface 36e of the external part 36 also has a symmetry of revolution with respect to this axis X. The first fixing elements 38 are here a thread cooperating with a thread (not shown) internal to the second orifices 16, 116, 117 allowing thus a screwing of the external part 36 inside the orifices 16, 116, 117. It is thus possible to fix in a non-definitive manner the introduction device 30 to the injector 10 or 110.

In the example shown in Figure 3, the second fastening elements comprise lugs or notches cooperating respectively with grooves or ribs of suitable shape to allow the external and internal parts to be moved between a state of fixing of the external and internal parts, in which these elements are integral with, and a state freed from these elements in which they can be separated from each other. The transition from one state to the other takes place following translational movements in a direction parallel to the axis of revolution X and of rotation about the axis of revolution X.

More specifically, in this example, the external part 36 has lugs 40 which project from its internal surface 36i perpendicular to the axis of revolution X, in the direction of the latter (radially). These lugs 40 cooperate with grooves 42 formed in the external surface 34e of the internal part 34. These grooves 42 have for example an L shape, a part of which extends parallel to the axis X from the edge of the orifice 32 , authorizing the insertion of the internal part 34 inside the external part 36 along a translation of axis X, the end of the groove 42 branching off at right angles so as to allow the internal part 34 to rotate by relative to the external part 36 and its blocking. FIG. 5 represents a cross-sectional view of the internal and external parts, before rotation of the internal part.

The invention is not limited to this particular embodiment: the pins 40 could be part of the internal part and the grooves be made on the external part. One could also consider replacing the lugs with notches cooperating no longer with grooves but with ribs parallel to the X axis, the length of which is chosen so that the rotation of the parts relative to each other allows support from the end of the ribs on the periphery without notch of the other part. The invention is also not limited to a particular number of ribs / grooves and notches / lugs.

Note that in the example of Figure 3, the outer part 36 is supported on a flange 35 of the internal part 34. This flange 35 thus forms a stop.

The example shown in FIG. 4 differs from that of FIG. 3 essentially by the shapes of the internal surface 36i of the external part 36 and of the external surface 34e of the internal part 34 and by the position of the pins 40. Consequently , the same elements are designated by the same references.

In this embodiment, an elastic element 44 is disposed between the internal 34 and external 36 parts so as to be compressed in a direction parallel to the axis X of the orifice 32 when the internal and external parts are fixed.

In the example, the elastic element 44 is in the form of a spring housed in an annular housing 46 with a U-section formed in the internal surface 36i. This elastic element 44 bears on the external surface 34e of the internal part 34 and is compressed when the lugs 40 are blocked in the corresponding grooves of the internal part. The elastic element 44 thus makes it possible to maintain the internal 34 and external 36 parts in position in the fixing state despite the vibrations, displacements and other movements transmitted by the injector.

The invention is not limited to the embodiments described, which can be combined.

The invention is particularly suitable for the injection of a hydrocarbon feedstock, in particular in an FCC unit, but could be adapted for the injection of any liquid feedstock to be atomized capable of eroding an injector.

Claims (10)

1. Device for introducing a liquid (30) inside an injector (10, 110) shaped to atomize said liquid into droplets by means of a gas, said introduction device comprising an orifice (32 ) crossing it right through, characterized in that it comprises: an internal part (34) of ceramic material, an internal surface (34i) of which defines said through orifice (32) over its entire length, an external part (36) made of metallic material at least partially surrounding the internal part (34), - the external and internal parts respectively having an internal surface (36i) and an external surface (34e) of complementary shapes allowing a displacement of the internal part with respect to the external part in a direction parallel to an axis of the through passage, said surfaces internal and external being provided with fastening elements (40, 42) cooperating to reversibly fix said internal and external parts. 2. Introducer (30) according to claim 1, characterized in that the external surface (34e) of the internal part (34) and the internal surface (36i) of the external part (36) are surfaces of revolution having an axis of revolution (X) coincident or parallel to the tax of the through orifice (32). 3. introduction device (30) according to claim 2, characterized in that the fastening elements comprise lugs (40) or notches cooperating respectively with grooves (42) or ribs of suitable shape to allow the movement of the parts external and internal between a state of fixation and a state released following movements of translation in a direction parallel to Taxe de revolution (X) and rotation around Taxe de revolution (X). 4. Introducer (30) according to any one of claims 1 to 3, characterized in that an elastic element (44) is disposed between the internal and external parts so as to be compressed in a direction parallel to the axis of the through hole when the internal and external parts are fixed. 5. Introducer (30) according to any one of claims 1 to 4, characterized in that an external surface (36e) of the external part (36) comprises fixing elements (38) intended to cooperate with an inlet orifice (16, 116, 117) of the injector (10, 110) and shaped to ensure a non-final fixing. 6. Introducer (30) according to claim 5, characterized in that the fastening elements (38) of the external surface of the external part comprise a thread. 7. Introducer (30) according to any one of claims 1 to 6, characterized in that the ceramic material is chosen from silicon carbide SiC, boron carbide EUC, silicon nitride S13N4, nitride aluminum AIN, boron nitride BN, alumina AI2O3, or mixtures thereof. 8. Introducer (30) according to any one of claims 1 to 6, characterized in that the ceramic material comprises a ceramic matrix chosen from silicon carbide SiC, boron carbide B4C, silicon nitride S13N4 , aluminum nitride AIN, boron nitride BN, alumina AI2O3, or mixtures thereof, ceramic matrix in which are incorporated fibers chosen from carbon fibers and ceramic fibers, ceramic fibers for example selected from crystalline alumina fibers, mullite fibers, crystalline or amorphous silicon carbide fibers, zirconia fibers, silica-alumina fibers, or mixtures thereof. 9. Liquid injector (10, 110) shaped to atomize a liquid into droplets by means of a gas, comprising a hollow body (12, 112) having: at least a first gas inlet port (14, 114) intended to be connected to a gas supply pipe, at least a second liquid inlet port (16, 116, 117) intended to be connected to a liquid supply conduit, at least one contact chamber (20, 120) formed inside the hollow body and into which said orifices open 5 inlet, at least one outlet port (18, 118) for the evacuation of the atomized liquid out of the hollow body, characterized in that said at least one second inlet port (16, 116, 117) is provided an introduction device (30) according to one 10 any of claims 1 to 8. 10. Reactor provided with at least one injector according to claim 9. 1/1