FR2540402A1 - DEVICE AND ASSEMBLY FOR DISTRIBUTING FLUID IN A BOILER BED REACTOR - Google Patents

Abstract

THE INVENTION RELATES TO GAS-LIQUID MIXING DISTRIBUTION DEVICES FOR REACTORS. IT RELATES TO A DISTRIBUTION DEVICE IN WHICH A NOZZLE16 TRANSMITS THE MIXTURE OF GAS AND LIQUID TO A CHAMBER12 UNDER PRESSURE WHICH SUPPLIES A BOILING BED20 THROUGH A SUPPORT GRILLE18. NOZZLE 16 INCLUDES SEVERAL DEFLECTOR PLATES WHICH ARE INCLINED WITH RESPECT TO THE AXIS OF THE SUPPLY DUCT 10 AND WITH RESPECT TO THE AXIS OF THE REACTOR. MOST OF THE MIXTURE ENTERS NEAR THE BOTTOM AND PREVENTS THE FORMATION OF STAGNING ZONES. APPLICATION TO THE FEEDING OF REACTORS FOR LIQUEFACTION OF COAL AND CATALYTIC TREATMENT OF HYDROCARBON MATERIALS.

Description

The present invention relates to a device

  distribution of a fluid stream, as well as an

  appears to introduce a uniformly charged feed stream and fluid stream into a pressure chamber and a bubbling bed

  of catalyst from a reactor.

  to bind a fluid distribution assembly for processing

  oil currents, coal suspensions in an oil and gas, so that they are distributed

  in a virtually uniform manner in a broth bed-

catalyst.

  Experiments with installation implementation

  Industrial reactors and processes used in the "H-Oil" and "H-Coal" processes have shown that an unsuitable realization of the distribution of the current at the inlet to the pressure chamber of the reactor could create

  operational difficulties, such as the forma-

  tion of coke in the pressure chamber, a bad

  current distribution in the catalyst bed, a

  localized bedding of the catalyst bed, and the formation

  de-coke in bed These problems have reduced the use of

  catalyst and required frequent shutdowns of the reactor, so that the operating periods

have been shortened.

  The prior art apparently does not know

  no suitable solution to the problem of

  Thus, U.S. Patent No. 3,197,288 discloses a catalytic reactor configuration having simple coils for introducing the feedstock and recycled liquid into the fluidized bed reactor.

  pressure chamber of the reactor, and the United States Patent

  United States No. 3,202,603 represents the use of double dabblers at the lower end

  In addition, the United States patent of

  No. 3,540,995 generally describes the implementation of

  implementation of a process for the treatment of coal by

  using a bubbling catalyst bed reactor in which the charge and

  recycled liquid are introduced into the chamber under pres-

  However, the introduction of the gas and liquid streams into a reactor pressure chamber at high speed requires more specific provisions for the currents to allow a higher flow rate. For this reason, improved fluid flow distribution devices have been developed to provide advantageously uniform flow diagrams.

  in the pressure chamber of the reactor.

  The present invention relates to a fluid distribution device and a distribution assembly for the introduction of hydrocarbon liquids and suspensions and a gas in a uniform manner into the pressure chamber and a bubbling catalyst bed of a reactor L The invention thus relates to a device for distributing a stream of a liquid-gas mixture in an ebullated bed reactor, the distribution device being placed in a pressure chamber of the reactor, this chamber being defined by a distribution grid and by the lower end and the walls

  bottom of the reactor, below the grid

  Positive distribution has a nozzle with deflection

  and placed at the inner end of a penetra-

  trant in the chamber under pressure so that a fluid

  hydrocarbon extracted at least in part from a reaction

  killed in the bubbling bed, is recycled, the baffle nozzle having at least two deflectors separated from one another and rigidly attached to the inner end of the conduit, the inner baffle being formed of a solid plate, another at least one deflector having a central orifice and being placed upstream of the deflector formed by the solid plate, so that the baffle nozzle mixes a gas and a liquid material transmitted by the conduit to

  inside the chamber under pressure, and it is

  It is arranged in such a way that, in combination with the distribution grid, it ensures a substantially uniform distribution of the liquid-gas mixture stream which rises in the bedbug.

  The invention also relates to a set of

  uniformly a current of a fluid material in a

  bubbling bed of a reactor, this set of

  comprising a pressure chamber formed at the bottom of the reactor and defined by the side walls and the lower end of the reactor and

  by a grid of distribution placed under the bed bouil-

  lonnant in the reactor, a duct opening into the chamber under pressure so that it carries the material

  fluid in the pressure chamber, and a deflection nozzle

  rigidly attached to the inner end of the duct, this nozzle having at least two remote deflectors one

  on the other hand, the internal deflector being

  than full, another deflector at least having a

  this central and being placed upstream of the deflector formed by the solid plate, so that the nozzle mixes a gas and a liquid material transmitted through the conduit in the vacuum chamber, and, in combination with the distribution grid, it ensures a substantially uniform distribution of the gas-liquid mixture introduced into the bubbling bed. The invention is particularly useful for the treatment of hydrocarbon feed streams such as oil and coal suspensions which must be uniformly distributed with hydrogen gas in a catalyst bed reactor.

  the term "gas-liquid mixture" also refers to the

  mixture of a gas and a suspension in a liquid containing

fine solid particles.

  Other features and advantages of the

  will be better understood when reading the description of

  following examples of embodiment and with reference to the accompanying drawings in which

  FIG. 1 is a vertical section of the section

  lower part of a bubbling bed reactor-implementing the invention,

  FIG. 2 is a vertical section of a device

  current distribution system with baffle nozzle;

  FIG. 3 is a section of a variant of FIG.

  positive device according to the invention, wherein the charging and recycled currents are introduced by separate circulation devices; and FIG. 4 represents another embodiment of

  invention, similar to that of FIG.

  In accordance with the present invention, the flow stream of, for example, a mixture of a slurry in a liquid, derived from coal, and hydrogen, flows through a conduit and a disc and ring type deflector nozzle dispensing device, into a c 1 chamber under pressure placed at the lower end of a reactor The device

  distributor usually contains a series of

  substantially parallel and distant deflectors,

  at an angle of 45 to 900 with the central axis of the former

  internal tremity of the conduit, the device ensuring the lateral or radial outflow of the current in the pressure chamber. In addition, the central axis of the deflector nozzle distributor device makes an angle of 0 to 60 with the central axis of the room under

  pressure and reactor vessel.

  of the inlet stream into the pressure chamber of the fluidized bed reactors, comprising

  solids and a gas-liquid mixture, constitutes a

  tif without clogging ensuring the dispersion of the kinetic energy of the fluid currents transmitted in the chamber

  under pressure The dispensing device prevents the

  "jets" with the stream of gas and recycled liquid

  introduced into the pressure chamber and disperses

  formally the liquid flow in this chamber.

  Depending on the operating conditions of the reaction

  tor and the available space in the pressure chamber, _

  the dispensing device can have various configurations

  It may consist of at least two deflector plates

  Preferably in the case of a location of a vertical nozzle in the chamber, these deflector plates are usually equally spaced from one another. The upper plate of the device distributor is full and deflects the inlet stream laterally to prevent liquid shock to the underside of

  the plate forming the grid The other plates of disper-

  sion or deflection of the device have

  traux whose dimensions are such that parts

  of the liquid stream are intercepted and deflected laterally.

  Normally or radially outwardly in the pressure chamber The flow paths of these side streams are directed to sweep the bottom of the chamber under pressure and eliminate stagnant areas while ensuring a good mixing of the gas and liquid (or

  suspension in a liquid and gas), with a

  substantially uniform upwards by the ori-

  these of the distribution grid, in the bubbling bed.

  The percentage of the total amount of material flowing radially outwardly from the space between the deflector plates may vary depending on the dimensions of the dispensing device, but

  a larger percentage of the current is emitted

  by the lower space In an example of

  baffle, 40 to 45% of the introduced liquid flow is deflected by the first plate, 25 to 35% by the middle plate and the rest is deflected radially outwards by the upper plate In the case of a configuration

  nozzle inserted into the chamber from one side, the

  The deflectors are usually oriented with an inclination of between 0 and 100 approximately with respect to the adjacent deflector plate so that the distribution of the flow of liquid and recycled gas is uniform.

in the pressure chamber.

  In the case of small diameter reactors,

  having internal diameters of less than 1.5 m, the

  lange of gas and charge liquid flows with

  the recycled liquid from the reactor outside of that

  ci, before the uniform distribution of the combined mixture in

  the pressure chamber of the reactor with the aid of

  As shown in FIG. 1 and described hereinafter, it is usually convenient. In the case of reactors having a diameter greater than about 1.8 m, the introduction of the mixture of gas and liquid feed into the chamber under reactor pressure is

  usually performed in a desirable manner by the

  For example, a perforated circular ring of splashing is

  usually placed in the upper part of the room

  under pressure and can be used for uniform distribution of the gas-liquid

  section of the pressure chamber of the reactor

  uniformly small bubbles and liquid charge is formed by creating, in the bubbler, a loss

  charge and direction of gas-gas mixing currents

  liquid from the bubbler downwards so that the energy

  The kinetics of the current dissipate almost

  This kinetic energy is used to increase the mixing intensity by returning liquid to the pressure chamber. The pressure drops at the bubble ring openings are usually between 0.07 and 0.07. 1 bar, in the case of heavy liquefaction of coal

  and improving the quality of crude oil.

  In a variant of the invention, the spill duct of the recycled liquid of the reactor can pass through

  center of the dispensing device which advantageously comprises

  The reactor's recycled liquid enters the pressure chamber through its annular zone between the weir and the inlet nozzle. The central orifices of the first plate and the central plate have dimensions such that

  the liquid stream is laterally and uniquely dispersed

  in a radial outward direction, in particular

  the chamber under pressure, and sweeps the bottom of the chamber by eliminating the stagnant areas The solid top plate prevents the direct impact of the liquid against the face

bottom of the grid.

  This inlet flow deflector nozzle splitter is used upstream of the reactor distribution grid with which it provides an improved flow distribution assembly for a bubbling bed reactor.

  of catalyst The loss of charge in the device

  Baffle nozzle splitter, for the nominal flow rate, is usually between 5% and 25% of the total load loss of the splitter and the grid Although the grid may be formed of a perforated plate, it preferably contains many

  tubes each having a cap at its upper end.

  This distribution set ensures excellent contact

  gas-liquid and an excellent gas mixture in the chamber.

  under pressure, eliminates the undesirable direct impact of the fluid streams on the grate, and minimizes the formation of coke in the pressure chamber and

in the catalyst bed.

  The invention is now described by reference

  in FIG. 1, which shows an inlet duct 10 penetrating

  trant in a chamber 12 under pressure of a reactor 14

  which may be coated with refractory insulation 15.

  The conduit comprises a distribution device 16 of cou-

  and a deflector nozzle or ring, generally upwardly oriented to transmit a mixture of gas and liquid into the pressure chamber, the fluid rising uniformly through the orifices 19 of the nozzle.

  the grid 18 of current distribution to the bed boil-

  The catalyst liquid is

  pulled up the top of the catalyst bed and goes down through the

  central duct 24 to a recycling pump (not re-

  presented) from which the liquid is returned

  with a new charge of gas and liquid, through the

  The pressure chamber 12 preferably has a height of 5 to 10 times the internal diameter of the inlet pipe and the distributor device 16.

  1-0, and the distribution grid 18 has

  a diameter of 4 to 12 times the internal diameter

duct 10.

  As indicated in more detail in FIG. 2, the current distribution device 16 comprises at least one annular plate 30 having a central orifice 31 which is upstream of a solid circular plate 32.

  the plates being retained by three rods 33 regularly

  distributed around the circumference and which are preferably

  placed on the outer edges of the deflector plates

  Usually, an additional annular plate

  34, having a smaller central hole 35, is

  placed between the plates 30 and 32 so that the

  The distribution device provides a radial distribution of the current from the conduit. A larger percentage of the flow is preferably emitted from the space.

  the lowest given the greater distance of

  placing the fluid in the chamber 12 before it

  ring the grid 18 In the case of a distributed device

  Advantageously having three plates, the dimensions of the plates are preferably chosen so that approximately 40 to 45% by volume of the fluid flow is deflected radially outwards by the first deflector.

  About 30 to 25% by volume are deflected out

  by the second deflector 44 and the rest is deflected

  radially by the upper plate 32.

  The three remote deflector plates are

  45 b 900 inclined to the central axis of the ex-

  In addition, the axis of the deflector nozzle makes an angle α between 0 and 600 with the central axis of the chamber 12 and the reactor 14. In addition, if necessary, the deflector plates can make an angle from 0 to 10 with adjacent baffle plate

  so that the gas-liquid mixture is uniformly dispersed

in room 12.

  FIG. 3 represents a variant configuration of a fluid distribution assembly according to the invention, in which the distribution device 16 is placed in the center, at the bottom of the chamber 12 under pressure, under

  grid 18, and is arranged above the bottom of the chamber.

  The gate 18 preferably contains a plurality of vertical tubes 26 having an internal diameter of 19 to 38 mm and protruding under the grid on a pressure gauge between 1.0 and 2.5 times the internal diameter of the inlet duct. distance 4 to 10 times the internal diameter of the tubes The tubes 26 protrude above the gate by a distance of the order of 1.5 to 4 times the internal diameter of the tube A cylindrical cap 28 is disposed above the upper end of each tube 26 away from the tube and is rigidly supported by the tube with suitable support members (not shown) The orientation of the cap 28 is such that the solid particles of the catalyst 22 from the bubbling bed can not enter the tubes 26, when no fluid updraft

  circulates in the tubes, for example during disturbances

  operating conditions or when shutting down the

  A circular bubbling ring 40 having

  Fits uniformly spaced 41 at its underside is placed above the distributor device 16 so that it evenly distributes the flow of liquid and gas

  in the upper part 12a of the pressure chamber.

  The sparger device 40 surrounds the weir 24 and is particularly useful in the case of large diameter reactors, for example exceeding approximately 2.4 m in internal diameter. The orifices 41 have a dimension such that they create a uniform pressure drop. and they are arranged in such a way that they direct the current down, the latter dissipating practically all of its kinetic energy whereas the mixture by return of gas and

  liquid in the pressure chamber is increased.

  In another embodiment of the invention,

  As shown in FIG. 4, weir 44 passes to the center of the baffle distribution device 46.

  This distribution device comprises three annular plates

  nulars supported by the duct 44 and receiving a cou-

  A solid upper plate 47 is fixed rigidly, for example

  by sounding at line 44 and is substantially perpendicular

  The intermediate plate 48 is fixed to the plate 47 by three regularly spaced rods 53 and at an annular orifice 49. The lower plate 50 has an annular orifice 51 which, to some extent, is greater than the orifice 49 formed in the intermediate plate.

  Thus, the distribution device 46 has a function

  similar to that of the device 16, a part of the total updraft of fluid flowing radially

  outwards by the spaces separating the plates.

  The circular bubbler device 60 also has a pressurized chamber 12 and is centrally located above the distributor device 46, as in the case of

configuration of Figure 3.

  The effectiveness of using the configuration of the input current divider is indicated by the following examples which should be considered

  purely illustrative and not limiting.

EXAMPLES

  In a coal hydrogenation plant implementing the "-Coal" process for liquefying coal and having a bubbling bed reactor of

  1.5 m internal diameter catalyst (reactor of the

  Catlettsburg "H-Coal" pilot plant of 180 t / day), the gas and the coal feed suspension are mixed with the stream of liquid recycled to boiling, outside the reactor The total combined current is then distributed by a nozzle penetrating laterally and having

  three inclined deflector plates as described in

  1 to the embodiment of FIG. 1 After placing the distribution nozzle in the chamber under

  pressure, coking in the bubbling bed of cata-

  lyseur, caused by a poor distribution of the current,

is virtually eliminated.

  In an industrial reactor using the "H-Coal" process (16,000 t / day) having an internal diameter of 3 × 3 m, the pressure chamber contains a

  nozzle penetrating laterally and having three deflector plates

  Including an inclined flow-through ring for dispersing the liquid suspension recycle stream and a circular bubble ring for distributing the gas and slurry in an industrial reactor employing the "H-Oil" process (5,600 m 27 d) having an internal diameter of 3 m, the set-of distribution of the input current in the pressure chamber of the reactor is formed of a vertical nozzle having three horizontal plates for dispersing the recycled ebullating liquid stream and a ring bubbling for distributing the current

  liquid and feed gas.

  Of course, various modifications may be made by those skilled in the art to the devices which have just been described as examples only.

  non-limiting without departing from the scope of the invention.

Claims (16)

  1 Dispatcher device for a current of a   liquid-gas mixture in a bubbling bed of a reactor, the distribution device being placed in the pressure chamber (12) of the reactor, this chamber being delimited by a distribution grid (18) and by the   lower walls and the lower end of the reaction   under the gate, said distribution device comprises   a deflector nozzle (16) located at the inner end of a conduit (10) penetrating into the chamber   pressure (12) and for recycling a hydrocarbon fluid   derived at least in part from a reaction carried out in the bubbling bed the nozzle (16) having at least two baffles (30, 32, 34) spaced from each other and fixed rigidly to the inner end of the duct, the deflector internal <32) being in the form of a solid plate, at least one other deflector (30, 34) having a central orifice and being placed upstream with respect to the deflector in the form of a solid plate, so that   the nozzle (16) mixes a gas and a liquid trans-   put in the duct inside the chamber under pres-   sion, and it is carried out in such a way that, in combination   with the grid (18) of distribution, it ensures a distribution   substantially uniform formation of the gas-liquid mixture in the bubbling bed.   2 Device according to claim 1, characterized in that the remote deflectors (30, 32, 34) make a   angle of 45 to 90 with the central axis of the end dull of the duct (10).   3 Device according to claim 1, characterized in that the nozzle (16) has an axis which is at an angle of 0 to 600 with the central axis of the pressure chamber (12) and the reactor.   4 Device according to claim 1, characterized in that it comprises three circular deflector plates (30, 32, 34), the lower plate (30) having a central orifice, the intermediate plate (34) having a central orifice smaller than that from the bottom plate, and   the upper plate (32) being full.   Device according to claim 4, characterized   in that the lower first (30) has a central orifice   tral whose diameter is between 0.6 and 0.75 times   the internal diameter of the duct (10), and the internal plate   medial (34) has a central orifice whose diameter is   between 0.4 and 0.5 times the internal diameter of the con- duit (10).   Device according to claim 1, characterized   in that the deflector plates (30, 32, 34) are separated   with a distance of between 0.3 and 0.5 times the internal diameter of the duct.   7 Device according to claim 1, characterized in that each deflector plate (30, 32, 34) makes   an angle of 0 to 100 with the adjacent baffle plate.   8 Device according to claim 1, characterized in that the pressure drop of the fluid in the dispensing device is between 5 and 25% of the total pressure drop of the fluid in the device and in the distribution grid.   9 Set of uniform distribution of a current   of a fluid material in a bubbling bed of a reaction   the said set being characterized in that it comprises   takes (a) a pressure chamber (12) formed in the lower part of the reactor and defined by side walls and the lower end of the reactor and by a distribution grid (18) placed beneath the bubbling bed formed in the reactor, (b) a conduit (10) entering the pressure chamber to transmit fluid material therein, and (c) a baffle nozzle (16) rigidly attached to the inner end of the chamber conduit (10) and having at least two remote deflectors (30, 32, 34), the inner deflector (32) being formed by a solid plate, and at least one other deflector (30, 34) having a central orifice and being positioned upstream of the deflector in the form of a solid plate, so that the nozzle (16) mixes a gas and a liquid material transmitted by the conduit into the pressure chamber and is arranged so that, in combination with the distribution grid it provides a sense uniformly uniform gas mixture   and liquid in the bubbling bed.   An assembly according to claim 9, characterized in that the remote deflectors (30, 32, 34) form an angle of 45 to 9 Q O with the axis of the inner end duct.   11 assembly according to claim 9, characterized in that the axis of the nozzle (16) is an angle of 0 to 60 with the central axis of the pressure chamber <12) and of the reactor.   12 assembly according to claim 9, characterized in that the nozzle (16) comprises three circular deflector plates (30, 32, 34), the first lower plate   (30) having a central orifice, the second plate   medial (34) having a central orifice smaller than that of the first lower plate, and the third   upper plate (32) being full.   13 An assembly according to claim 9, characterized in that the first lower plate (30) has a central orifice whose diameter is between 0.6 and 0.75 times the internal diameter of the conduit (10), and the intermediate plate {34) has a central orifice whose diameter is between 0.4 and 0.5 times the internal diameter duct (10).   Assembly according to Claim 9, characterized   in that the deflector plates (30, 32, 34) are separated   trimmed with a distance between 0.3 and 0.5 times the internal diameter of the duct.   Assembly according to Claim 9, characterized   in that a bubbling device (40) of annular shape   is placed in the pressure chamber under the   distribution grid (18) and above the nozzle.   Assembly according to claim 9, characterized in that the baffle nozzle (16) protrudes above the bottom of the pressure chamber (12) of the reactor by a distance between 1.0 and 2.5 times the diameter. internal duct (10). Assembly according to Claim 9, characterized in that the pressure chamber (12) has a height   between 5 and 10 times the internal diameter of the con- duit (10).   Assembly according to Claim 8, characterized in that the distribution grid (18) has a diameter   between 4 and 12 times the internal diameter of the con- duit (10).   19 Uniform distribution of a material   fluid in a bubbling bed of a reactor, said reactor   it seems to be characterized in that it comprises (a) a pressure chamber (12) formed in the lower part of the reactor and delimited by the side walls and the lower end of the reactor and by a distribution grid (18) placed under the bubbling bed formed in the reactor, (b) a weir (44) passing vertically through the distribution grid (18) and the pressure chamber (12) to transfer recycled fluid from the bed   bubbling to the chamber under pressure.   (c) a conduit entering the vacuum chamber for transmitting a fluid material into the chamber, and (d) a deflector nozzle (46) rigidly attached to the inner end of the conduit, which nozzle has   least two deflectors (47, 48, 50), the deflec-   internal reactor (47) being in the form of a solid plate and at least one other deflector (48, 50) having a central orifice and being placed upstream of the deflector in the form of a solid plate, so that the nozzle (46 ) with baffles mixes a gas and a liquid material transmitted through the conduit into the pressure chamber and is disposed of 2540402-   in combination with the distribution grid   it ensures a substantially uniform distribution   gas-liquid mixture in the bubbling bed.   Assembly according to claim 19, characterized in that the weir (44) is placed in the center of the pressure chamber and passes vertically through the grid and the pressure chamber, and the nozzle is disposed outside the weir and concentrically to this one.