Swirl nozzle, tubular distributor, fluidized bed reaction device, and hydrocarbon ammoxidation method

Abstract

The present invention relates to the technical field of chemical apparatuses. Disclosed are a swirl nozzle, a tubular distributor, a fluidized bed reaction device and a hydrocarbon ammoxidation method. The swirl nozzle comprises: a housing, the housing defining a swirl chamber, the swirl chamber comprising an upper swirl chamber and a lower swirl chamber, a bottom end opening being formed in the bottom end of the lower swirl chamber, and the housing being provided with a nozzle feed port that leads to the upper swirl chamber; and a central column arranged inside the swirl chamber, the bottom end of the central column extending towards the bottom end opening of the lower swirl chamber, the bottom end of the central column being connected to a flow guide, and a nozzle discharge port with an annular gap being formed between the flow guide, the bottom end of the central column and the bottom end opening of the lower swirl chamber. The present invention can enhance the uniform gas distribution performance of tubular distributors, and further improve the yield of ammoxidation products.

Description

Swirl nozzle, tubular distributor, fluidized bed reaction device and hydrocarbon ammoxidation reaction method Technical Field

[0001] The present invention relates to the technical field of chemical equipment, in particular to a swirl nozzle, a tubular distributor, a fluidized bed reaction device and a method for hydrocarbon ammoxidation reaction. Background Art

[0002] Tubular distributors are commonly used in catalytic cracking reactors and hydrocarbon ammoxidation reactors. They feature free ends, which address thermal expansion and multi-stage gas feed issues. They are particularly suitable for large reactors and processes requiring multiple gas feeds. Currently known tubular distributors typically consist of a main pipe, branch pipes, branch pipes, and nozzles.

[0003] Existing tubular distributor nozzles are often simply short tubes connected to branch pipes. When the airflow enters the nozzle from the branch pipe, the sudden change in flow direction can cause severe flow deviation and even cause backflow of materials (such as catalyst) outside the tubular distributor due to localized pressure reduction. While pressure swirl nozzles, a type commonly used in liquid atomization, offer relatively uniform distribution, they also suffer from strong backflow due to central centrifugal pressure reduction, making them difficult to use in reactors containing particulate materials (such as catalyst particles), such as hydrocarbon ammoxidation reactors.

[0004] CN204017797U discloses a feed distributor for an ammonia oxidation reactor. The different sections of the feed distributor used in a commercial ammonia oxidation reactor are conveniently replaced by attaching the various sections of the distributor to each other and the wall of the reactor using airtight quick disconnect fittings. In addition, the diameters of the branch pipes in these distributor sections and the diameters of the feed nozzles attached to these branch pipes are changed to facilitate the uniform flow of the feed gas through these components. The distributor can be subdivided into a plurality of feed distributor sections arranged for better reactor control. Finally, the end cap terminated at the far end of the distributor branch pipe can be provided with a nozzle for removing any ammonia oxidation catalyst that may unintentionally reach the inside of the distributor.

[0005] Generally, as the size of the reactor increases, the problem of uneven flow field in the distributor becomes more serious.

[0006] Therefore, there is still a need for a flow nozzle capable of enhancing the uniform gas distribution performance of a tubular distributor, as well as a tubular distributor and a fluidized bed reaction device comprising such a swirl nozzle.

[0007] SUMMARY OF THE INVENTION

[0008] In order to overcome the problems existing in the prior art, the inventors have discovered through extensive CFD simulations, flow field analysis, and specific experimental studies that a new type of swirl nozzle can enhance the uniform gas distribution performance of a tubular distributor. Thus, provided are the new type of swirl nozzle, a tubular distributor and a fluidized bed reactor comprising the swirl nozzle, and a method for hydrocarbon ammoxidation, catalytic cracking, nitrobenzene hydrogenation, coal gasification, or trichlorosilane cold hydrogenation using the fluidized bed reactor.

[0009] An object of the present invention is to provide a swirl nozzle, comprising:

[0010] A housing, wherein the housing surrounds and defines a swirl chamber, the swirl chamber includes an upper swirl chamber and a lower swirl chamber, the bottom end of the lower swirl chamber forms a bottom end opening, and the housing is provided with a nozzle feed port communicating with the upper swirl chamber;

[0011] A central column is disposed in the swirl chamber, wherein the top end of the central column is connected to the top wall of the shell of the swirl chamber, the bottom end of the central column extends toward the bottom opening of the lower swirl chamber, the bottom end of the central column is connected to a guide body, and a nozzle discharge port with an annular gap is formed between the guide body, the bottom end of the central column, and the bottom opening of the lower swirl chamber;

[0012] The material entering from the nozzle feed port can flow along the inner peripheral wall of the swirl chamber to form a downward swirl around the central column, and the downward swirl is ejected in an umbrella shape through the nozzle discharge port.

[0013] Another object of the present invention is to provide a tubular distributor, which includes a branch pipe and multiple branch pipes connected to the branch pipe, and multiple swirl nozzles described in the present invention are installed on the branch pipe. The connecting ends of the branch pipe and the branch pipe are provided with rectifying components that can enhance logistics distribution.

[0014] Another object of the present invention is to provide a fluidized bed reaction device, which comprises a reaction chamber, wherein a material distributor is provided in the reaction chamber, and the material distributor comprises the tubular distributor described in the present invention.

[0015] Another object of the present invention is to provide the use of the swirl nozzle of the present invention, the tubular distributor of the present invention, or the fluidized bed reaction device of the present invention in ammonia oxidation, catalytic cracking, nitrobenzene hydrogenation, coal gasification, or trichlorosilane cold hydrogenation reaction.

[0016] Another object of the present invention is to provide a method for hydrocarbon ammoxidation, which is carried out using the fluidized bed reactor of the present invention, wherein the material distributor in the fluidized bed reactor comprises at least one of the tubular distributors and a gas distribution plate.

[0017] The method includes:

[0018] The raw materials containing hydrocarbon source and ammonia source are passed through the tubular distributor into the reaction chamber,

[0019] allowing oxygen-containing gas to enter the reaction chamber through the gas distribution plate;

[0020] In the reaction chamber, a raw material containing a hydrocarbon source and an ammonia source is contacted with an oxygen-containing gas in the presence of a catalyst, preferably in a countercurrent manner, to form a reaction effluent.

[0021] Through the above technical solution, the swirl nozzle of the present invention enables the incoming material to flow along the inner wall of the swirl chamber to form a downward swirl around the central column, and is ejected in an umbrella shape through the nozzle discharge port. On the one hand, it can achieve a more optimized material flow distribution effect, and on the other hand, it can eliminate the influence of backflow of materials outside the swirl nozzle caused by local decompression; the rectifying component of the tubular distributor of the present invention can eliminate the gas deviation inside the tubular distributor, so that the gas distribution performance of the distributor is closer to the ideal gas distribution state, and the uniform distribution of the gas flow is enhanced; further, the reaction materials of the fluidized bed reaction device of the present invention are closer to the ideal gas distribution state, so that the reaction materials are fully contacted, and the raw material conversion rate is improved; further, the method of hydrocarbon ammoxidation reaction of the present invention has the effect of improving the yield of ammoxidation products.

[0022] BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic diagram of a fluidized bed reaction apparatus according to some embodiments of the present invention;

[0024] FIG2 is a schematic structural diagram of the tubular distributor in FIG1 ;

[0025] FIG3 is a schematic structural diagram of the branch pipe-branch pipe in FIG2 ;

[0026] FIG4 is a schematic diagram of a branch pipe-branch pipe in a form of FIG2;

[0027] FIG5 is a schematic diagram of another form of branch pipe-branch pipe in FIG2;

[0028] FIG6 is a schematic diagram of the connection between the branch pipe and the branch pipe in FIG2 (top view);

[0029] FIG7 is a schematic diagram of the three-dimensional structure of the swirl nozzle in FIG2;

[0030] FIG8 is a longitudinal sectional view of a swirl nozzle;

[0031] FIG9 is a cross-sectional view of the swirl nozzle at the nozzle feed port;

[0032] FIG10 is a schematic structural diagram of a tubular distributor of the prior art;

[0033] FIG11 is a flow distribution comparison diagram of the distributor using a variable diameter and a rectifying component of the present invention and a conventional distributor.

[0034] In the drawings, the meanings of the various reference numerals are as follows: 1 is a gas collecting chamber; 2 is a reaction chamber; 3 is a heat exchange device; 4 is a tubular distributor; 5 is a hydrocarbon source; 6 is an ammonia source; 7 is a gas distribution plate; 8 is an oxygen-containing gas; 9 is a second material inlet; 10 is a cyclone separator; 11 is a first material outlet; 12 is a main pipe; 13 is a branch pipe; 14 is a branch pipe; 15 is a mainstream direction of logistics; 16 is a rectifying component; 17 is a straight tube shell; 18 is a different-diameter curved tube shell; 19 is a swirl nozzle; 20 is an incoming gas in the branch pipe; 21 is a nozzle feed port; 22 is an upper swirl chamber; 23 is a lower swirl chamber; 24 is a center column; 25 is a nozzle discharge port; 26 is a guide body; 211 is a first inner wall.

[0035] Detailed Description of the Preferred Embodiments

[0036] The following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0037] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0038] In the present disclosure, unless otherwise specified, directional words such as "upper", "lower", "top" and "bottom" are usually used with reference to the directions shown in the drawings, or are used to describe the relative positional relationships of components in the vertical, perpendicular or gravity directions; "inside" and "outside" usually refer to the inside and outside of a cavity relative to an inner cavity or the radial inside and outside relative to the center of a circle.

[0039] 7 and 8 , a first aspect of the present invention provides a swirl nozzle 19 comprising:

[0040] The housing defines a swirl chamber, which includes an upper swirl chamber 22 and a lower swirl chamber 23. The lower swirl chamber 23 is configured as a tapered chamber that tapers downward, with a bottom opening formed at the bottom end. The housing is provided with a nozzle feed port 21 that communicates with the upper swirl chamber 22.

[0041] The center column 24 is disposed in the swirl chamber. The top of the center column 24 is connected to the top wall of the shell of the swirl chamber. The bottom of the center column 24 extends to the bottom opening of the lower swirl chamber 23. The bottom end of the center column 24 is connected to a guide body 26. A nozzle discharge port 25 with an annular gap is formed between the guide body 26, the bottom end of the center column 24 and the bottom opening of the lower swirl chamber 23.

[0042] The material entering from the nozzle feed port 21 can flow along the inner peripheral wall of the swirl chamber to form a downward swirl around the central column 24 , and the downward swirl is ejected in an umbrella shape through the nozzle discharge port 25 .

[0043] As shown in FIG. 8 , the arrangement of the components in the swirl nozzle of the present disclosure enables the entire shell to be sleeved around the center column 24 and the guide body 26 , but not in contact with the guide body 26 .

[0044] The use of the swirl nozzle disclosed herein to convey materials can, on the one hand, achieve a more optimized material flow distribution effect, and on the other hand, eliminate the impact of backflow of materials (such as catalysts) outside the swirl nozzle caused by local decompression.

[0045] In some preferred embodiments, as shown in FIG8 , the flow guide 26 includes a gradually expanding section whose cross-section gradually increases in an axially downward direction. The small end of the gradually expanding section is connected to the bottom end of the center post 24. In some preferred embodiments, the cross-sectional area of ​​the large end of the gradually expanding section is larger than the area of ​​the bottom opening of the lower vortex chamber 23, for example, 1-2.73 times, preferably 1-2.25 times, of the area of ​​the bottom opening of the lower vortex chamber 23.

[0046] It should be noted that, in the present disclosure, the material that flows back into the swirl nozzle 19 is exemplified by catalyst particles, but the present invention is not limited to this. In some exemplary fluidized bed reactors, the catalyst particles will be carried upward by the gas (such as air) fed from the bottom, and the nozzle outlet 25 of the swirl nozzle 19 is located above the gas feed port of the bottom feed, and the nozzle outlet 25 faces the bottom of the fluidized bed reactor. In this way, since the gas velocity at the nozzle outlet 25 is greater, the formation of local decompression will cause the catalyst particles that follow the gas upward to be sucked into the swirl nozzle. The gradually expanding section of the flow guide 26 provided in the present disclosure can effectively prevent the backflow of the catalyst.

[0047] In some embodiments, the gradually expanding section is configured to be in the shape of a truncated cone, and the small end of the truncated cone is connected to the bottom end of the center column 24. The connection surface between the two can be located above, below or flush with the bottom end surface of the conical cavity; the distance in the height direction between the connection surface between the gradually expanding section and the center column 24 and the bottom end surface of the conical cavity is 0-0.1 times the diameter of the bottom end of the center column 24.

[0048] According to the present disclosure, the center column 24 can be a cylindrical column with a constant diameter, or a tapered column with a diameter gradually decreasing from top to bottom. The ratio of the large end diameter to the small end diameter of the tapered column can be in the range of 1-3, such as 1-2 or 1-1.5.

[0049] In some preferred embodiments, a tapered section with a gradually decreasing cross-section along the axial direction is provided below the diverging section. For example, the tapered section can be configured as a cone or a semi-spherical shape. Thus, when the gas fed from below the swirl nozzle 19 carries particulate matter, such as catalyst particles, and passes upward through the conical tapered section, the catalyst particles are dispersed. This not only increases the contact area with the reactants, but also moves the dispersed catalyst away from the nozzle outlet 25, thereby preventing it from being drawn into the nozzle due to a pressure differential.

[0050] In some preferred embodiments, the converging and diverging sections are connected by a buffer section. The converging, diverging, and diverging sections can be integrally formed, with the buffer section being cylindrical or drum-shaped with a central bulge. This results in a longitudinal cross-section of the guide body 26 being roughly elliptical or spindle-shaped. The buffer section in the middle increases the spacing between the converging and diverging sections, allowing particles dispersed through the conical converging section to move further away from the nozzle outlet 25 upon reaching the height of the nozzle outlet 25, thereby preventing them from being drawn into the nozzle 19 and eliminating the effect of backflow.

[0051] In the present invention, the nozzle feed port 21 is connected to the circumferential wall of the housing and communicates with the upper swirl chamber 22. The nozzle feed port 21 extends along the tangential, involute, or helical direction of the inner circumferential wall of the housing, allowing the material to be fed along one of the tangential, involute, or helical directions of the swirl chamber 22. In some embodiments of the present invention, as shown in FIG7 , the nozzle feed port 21 extends along the tangential direction of the inner circumferential wall of the housing.

[0052] In the present invention, as shown in Figure 9, the angle β between the intersection of the first inner wall 211 of the nozzle feed port 21 and the inner circumferential wall of the shell and the line connecting the center of the shell and the inner wall 211 can be in the range of 45°-150°, for example, in the range of 60°-120° or 75°-105°, conveniently 60°, 90° or 120°.

[0053] In the present invention, the normal cross-section of the nozzle feed port 21 in the material flow direction is rectangular, circular or elliptical.

[0054] In the present invention, the upper swirl cavity 22 is a cylindrical or truncated cone-shaped cavity. Preferably, the ratio of the height of the cylindrical cavity and / or truncated cone-shaped cavity to the diameter of the middle circle is in the range of 0.1-10, for example, in the range of 0.2-5.

[0055] When the upper swirl cavity 22 is a truncated cone-shaped cavity, the ratio of the maximum diameter to the minimum diameter of the truncated cone-shaped cavity is preferably 0.1-10, for example, in the range of 0.2-5.

[0056] In the present invention, the top diameter of the conical lower swirl chamber is the same as the diameter of the bottom end of the upper swirl chamber 22, and the ratio of the bottom diameter of the conical chamber to the top diameter is 0.1-10, for example, in the range of 0.2-5. It should be noted that the lower swirl chamber of the nozzle in the present invention is not limited to the downward-conical chamber shown in Figures 7 and 8. According to actual use requirements, it can also be a downward-expanding conical chamber or a cylindrical chamber. In the embodiments of the present invention, only the downward-conical chamber is used as an example to illustrate the advantages of the present invention, but the present invention is not limited to this.

[0057] Referring to Figures 2-6 , a second aspect of the present invention provides a tubular distributor 4 comprising a branch pipe 13 and multiple branch pipes 14 connected thereto. Each branch pipe 14 is equipped with multiple swirl nozzles 19 according to the present invention. Each branch pipe 14 is provided with a flow straightening member 16 at the connection end to the branch pipe 13. The flow straightening member 16 helps eliminate gas flow deviations within the tubular distributor 4, thereby enhancing uniform flow distribution. As shown in Figure 11 , CFD analysis demonstrates that the configuration of these components significantly suppresses flow deviations and turbulence within the distributor, enhancing uniform flow distribution.

[0058] In the present invention, as shown in Figure 3, the tubular distributor 4 has a tree-shaped tubular distribution structure; multiple branch pipes 14 are arranged on both sides of each branch pipe 13, and the multiple branch pipes 14 on both sides can be symmetrically arranged with the branch pipe 13 as the axis, and the length can gradually decrease from the middle of the branch pipe toward the two ends.

[0059] In the present invention, the branch pipes 14 extend radially along the branch pipe 13. One end of each branch pipe 14 is connected to the side of the branch pipe 13 through the rectifying member 16, and the other end is closed. The cross section of the branch pipe 14 can be circular, elliptical, or rectangular.

[0060] In some preferred embodiments, along the mainstream direction 15 of the feed flow, the branch pipe 13 is a tapered pipe with a continuous or gradually decreasing lumen cross-section. This design can more evenly distribute the gas flow of the branch pipe 13 into each branch pipe 14. Preferably, the branch pipe 13 is a tube with a circular cross-section at each location, wherein the ratio of the minimum cross-sectional diameter to the maximum cross-sectional diameter of the tube is 0.1-0.9. More preferably, the branch pipe 13 is composed of multiple sections of circular tubes of different diameters connected end to end. Further preferably, the ratio of the length of each section of the circular tube to the total length of the branch pipe 13 is 0.05-0.95. As shown in Figure 2, in the present invention, the tubular distributor 4 also includes a main pipe 12, and a plurality of branch pipes 13 are radially arranged, preferably evenly arranged on the side of the main pipe 12, and one end of the branch pipe 13 is connected to the main pipe 12, and the other end is set to be closed.

[0061] By providing the main pipe 12 and the plurality of branch pipes 13, the gas raw material enters from the main pipe 12, is distributed to the plurality of branch pipes 13, and finally is distributed to all the branch pipes 14. This can greatly increase the ventilation capacity, increase the chemical reaction output, and help reduce the unit cost of the device operation and improve economic efficiency.

[0062] In some preferred embodiments, the flow straightening member 16 is a section of tapered pipe. As shown in Figures 4-6 , the larger end of the flow straightening member 16 radially connects to the branch pipe 13, while the smaller end connects to the branch pipe 14. The flow straightening member 16 and the branch pipes can have various shapes. For example, as shown in Figures 4 or 5 , the flow cross-section of the flow straightening member 16 can be circular, elliptical, or rectangular to connect with the corresponding circular or square branch pipes. While the embodiments of the present invention use circular branch pipes as an example to illustrate the advantages of the present invention, the present invention is not limited thereto.

[0063] In some preferred embodiments, the tubular shell forming the flow-regulating member 16 can be axially configured as consisting of a straight tubular shell 17 and a curved tubular shell 18. Specifically, the straight tubular shell 17 and the curved tubular shell 18 located below the straight tubular shell 17 together form the variable-diameter tubular cavity of the flow-regulating member 16. The radial cross-section of the curved tubular shell 18 is a concave arc, as shown in FIG6 . The diameter of the concave arc gradually decreases along the flow direction within the flow-regulating member 16 until the cross-sectional area of ​​the tubular cavity formed by the straight tubular shell 17 is equal to the cross-sectional area of ​​the branch pipe 14. In one specific embodiment, viewed in the longitudinal cross-section of the flow-regulating member 16, the profile of the curved tubular shell 18 along the flow direction within the flow-regulating member 16 is one of a circular arc, an elliptical arc, or a parabola. The straight tubular shell 17 and the curved tubular shell 18 are connected by a smooth radial transition to reduce resistance to airflow flowing through the flow-regulating member 16.

[0064] In some preferred embodiments, the angle α between the outer contour of the straight tube shell 17 and the main flow direction 15 of the branch pipe 13 can be 90°-175°, for example, 105°-165° or 120°-150°; along the flow direction in the rectifying component 16, the profile of the different-diameter curved tube shell 18 is one of a circular arc, an elliptical arc or a parabola.

[0065] A third aspect of the present invention provides a fluidized bed reaction device, which is characterized by comprising a reaction chamber 2 and a material distributor disposed in the reaction chamber 2, wherein the material distributor comprises the tubular distributor 4 of the present invention.

[0066] In the present invention, preferably, the material distributor includes at least one tubular distributor 4 and a gas distribution plate 7. Preferably, the ratio of the vertical distance between the gas distribution plate 7 and the adjacent tubular distributor 4 to the height of the reaction chamber 2 is 0.01-0.15, for example, 0.01-0.10 or 0.015-0.09.

[0067] The fluidized bed reaction apparatus of the present invention is particularly suitable for ammonia oxidation reaction. In such a case, the fluidized bed reaction apparatus also includes some structures included in conventional ammonia oxidation reaction apparatuses in the prior art, such as the gas collecting chamber 1, the cyclone separator 10 and the heat exchange device 3 as shown in Figure 1.

[0068] In some embodiments of the present invention, as shown in FIG1 , the fluidized bed reaction apparatus comprises:

[0069] Gas collecting chamber 1

[0070] Reaction chamber 2;

[0071] A tubular distributor 4 and a gas distribution plate 7 are provided in the reaction chamber 2;

[0072] A first material inlet 27, a second material inlet 9, and a first material outlet 11 are connected to the reaction chamber 2, wherein the first material inlet 27 is in fluid communication with the tubular distributor 4 and is used to deliver gas feeds 5 and 6;

[0073] A heat exchange device 3 disposed in the reaction chamber 2; and

[0074] The cyclone separator 10 is connected to the air collecting chamber 1.

[0075] In one embodiment, the first material outlet 11 is provided at the top of the fluidized bed reactor and communicates with the gas collecting chamber 1. Generally, a constricted section is formed at the bottom of the reaction chamber, the bottom end of which extends downward to form a second material outlet 28, which is equipped with a control valve.

[0076] In the fluidized bed reactor of the present invention, gaseous feedstocks 5 and 6 enter the reaction chamber 2 through the tubular distributor 4 via the first material inlet 27 and react with gaseous feedstock 8, which enters the reactor through the second material inlet 9 and passes through the gas distribution plate 7, in the presence of fluidized catalyst particles, to form a reaction effluent. The majority of the catalyst particles fall back into the reaction zone. The gaseous reaction effluent, which carries some catalyst particles, passes through a cyclone separator 10 to separate the majority of the entrained catalyst particles, enters the gas collection chamber 1, and is then discharged through the first material outlet 11. In the embodiment of the present invention shown in Figure 1, the first material inlet 27 is arranged below the cyclone separator 10, the first material inlet 27 is connected to the main pipe 12 of the tubular distributor 4, and the nozzle outlet 25 of the swirl nozzle 19 of the tubular distributor 4 is toward the bottom space of the reaction chamber 2; the second material inlet 9 is arranged below the first material inlet 27, and is arranged to be a pipe radially penetrating the cavity wall of the necking section, and the pipe located in the reaction chamber is bent downward, so that the gas entering through the second material inlet 9 is reflected by the cavity wall of the necking section and dispersed upward through the gas distribution plate 7 arranged above the second material inlet 9 to be distributed upward again; the gas distribution plate 7 is arranged below the tubular distributor 4, so that the material of the first material inlet is in countercurrent contact with the material of the second material inlet and fully reacts.

[0077] A fourth aspect of the present invention provides the use of the swirl nozzle of the present invention, the tubular distributor of the present invention, or the fluidized bed reaction device of the present invention in hydrocarbon ammoxidation, catalytic cracking, nitrobenzene hydrogenation, or coal gasification.

[0078] A fifth aspect of the present invention provides a method for hydrocarbon ammoxidation, which is carried out in a fluidized bed reactor of the present invention, wherein the material distributor in the fluidized bed reactor includes at least one tubular distributor 4 and a gas distribution plate 7.

[0079] Preferably, the method of the present invention comprises: a raw material containing a hydrocarbon source and an ammonia source enters the reaction chamber 2 through a tubular distributor 4, and an oxygen-containing gas enters the reaction chamber 2 through a gas distribution plate 7; in the reaction chamber, the raw material containing a hydrocarbon source and an ammonia source contacts the oxygen-containing gas in the presence of a catalyst, preferably, the raw material containing a hydrocarbon source and an ammonia source contacts the oxygen-containing gas in reverse to form a reaction effluent.

[0080] According to the present invention, the feedstock containing a hydrocarbon source and an ammonia source is ejected from the tubular distributor 4 through the swirl nozzle 19, mixed with an oxygen-containing gas, and subjected to an ammoxidation reaction under the action of a catalyst. This method improves the uniformity and utilization of the feedstock, thereby increasing the yield of the ammoxidation product.

[0081] In the present invention, the unevenness of the flow discharged from the tubular distributor 4 can be as low as 0-0.35, wherein the unevenness calculation formula is: Where n is the number of swirl nozzles 19, u i is the discharge flow of the swirl nozzle 19, is the average flow rate sprayed from the swirl nozzle 19. According to the present invention, for example, n can be 400-2400.

[0082] According to the present invention, in the specific implementation process, only the main inlet flow rate is controlled (generally it can be controlled to 5×10 3 -1.4×10 5 m 3 / h), and the flow rate of each nozzle can be naturally formed by setting the device of the present invention. i The range is 0.8-580m 3 / h, The range is 1-350m 3 The unevenness of the spray flow rate of the tubular distributor 4 can be reduced to 0-0.35, for example, lower than 0.10, lower than 0.08, or even lower than 0.05.

[0083] According to some embodiments of the present invention, a catalyst may be pre-loaded above gas distribution plate 7. Oxygen-containing gas entering from the second bottom material inlet carries the catalyst and contacts and mixes with the hydrocarbon and ammonia source feedstock, producing a reaction effluent containing nitrile products. The reaction effluent enters cyclone separator 10 for separation. The gas stream from which the catalyst has been separated enters gas collection chamber 1. The catalyst separated from cyclone separator 10 falls back through the feed leg into the reaction zone bed.

[0084] In the present invention, the molar ratio of the hydrocarbon source calculated as hydrocarbon, the ammonia source calculated as ammonia and the oxygen-containing gas calculated as oxygen molecules is preferably 1:(1-10):(10-40).

[0085] In the present invention, the hydrocarbon source preferably includes hydrocarbons and / or hydrocarbon derivatives, and more preferably includes at least one of toluene, p-chlorotoluene, o-chlorotoluene, o-xylene, m-xylene, p-xylene, dichlorotoluene, trichlorotoluene or 4-nitro-o-xylene.

[0086] The present invention has no special requirements for the ammonia source and the oxygen-containing gas. For example, the ammonia source is ammonia or a mixed gas containing ammonia. For example, the oxygen-containing gas is oxygen or a mixed gas containing oxygen, such as air.

[0087] In the method of the present invention, preferred contact conditions include: reaction temperature of 300-500° C., pressure of 0.01-0.2 MPa, and gas superficial linear velocity of 0.1-0.8 m / s.

[0088] In the method of the present invention, the catalyst may be a catalyst commonly used in the prior art for hydrocarbon ammoxidation reaction, such as NC-III or other vanadium-chromium series silica-supported particle catalysts. Example

[0089] The present invention is further described below using examples, but the present invention is not limited thereto.

[0090] In the following examples, air is used as an example of oxygen-containing gas, ammonia is used as an example of ammonia source, and NC-III catalyst is used as an example of catalyst (the present invention has no special requirements for the catalyst, and catalysts commonly used in the art can be applied to the present invention).

[0091] The following examples were conducted in the fluidized bed reactor shown in Figures 1-8 . The fluidized bed reactor comprises a reaction chamber 2, within which is disposed a heat exchanger 3 and a tubular distributor 4. A first material outlet 11 is provided at the top of the reaction chamber, communicating with a gas collection chamber 1, which in turn communicates with a cyclone separator 10. Below the cyclone separator 10 is a first material inlet 27 communicating with the tubular distributor 4. The nozzle outlet 25 of the swirl nozzle 19 of the tubular distributor 4 faces the bottom space of the reaction chamber 2. A gas distribution plate 7 is provided below the tubular distributor 4. Below the gas distribution plate 7 is a second material inlet 9.

[0092] The tubular distributor 4 comprises a main pipe 12, with multiple branch pipes 13 radially and evenly arranged on the sides of the main pipe 12. Each branch pipe 13 has one end connected to the main pipe 12 and the other end sealed. The branch pipes 13 are composed of multiple sections of circular pipes of varying diameters, connected end to end. Multiple branch pipes 14 extend radially along the branch pipe 13. Each branch pipe 14 has one end connected to the side of the branch pipe 13 via a straightening member 16, and the other end sealed. The straightening member 16 is a section of pipe with a variable diameter. The larger end of each straightening member 16 is radially connected to the branch pipe 13, while the smaller end is connected to a branch pipe 14. The pipe shell forming the straightening member 16 consists of a straight pipe shell 17 and a curved pipe shell 18 with a different diameter. The straight pipe shell 17 and the curved pipe shell 18 are connected by a smooth transition along the radial direction. The curved pipe shell 18 has a parabolic profile along the flow direction within the straightening member 16.

[0093] The swirl nozzle 19 includes: a shell, which defines a swirl chamber, which includes an upper swirl chamber 22 and a lower swirl chamber 23, the lower swirl chamber 23 is configured as a tapered chamber that tapers downward, and the bottom end of the tapered chamber is formed with a bottom opening, and the upper swirl chamber 22 is provided with a nozzle feed port 21; a central column 24 arranged in the center of the swirl chamber, the top of the central column 24 is connected to the shell top wall of the swirl chamber, the bottom end of the central column 24 extends to the bottom opening of the lower swirl chamber 23 and is connected to a guide body 26, and a nozzle discharge port 25 with an annular gap is formed between the guide body 26, the bottom end of the central column 24 and the bottom opening of the lower swirl chamber 23; the guide body 26 includes, from top to bottom, a truncated cone-shaped expanding section, a drum-shaped or cylindrical buffer section and an inverted conical tapered section, and the small end of the truncated cone-shaped expanding section is connected to the bottom end of the central column 24.

[0094] The method for hydrocarbon ammoxidation reaction includes: introducing a feedstock containing a hydrocarbon source 5 and an ammonia source 6 into a first material inlet, and introducing air 8 into a second material inlet; the feedstock containing the hydrocarbon source 5 and the ammonia source 6 is contacted with the air 8 carrying an NC-III type catalyst in a reaction chamber 2 to form a reaction effluent containing nitrile products; the gaseous reaction effluent, after natural separation from the fluidized catalyst, enters a cyclone separator 10, where the gas is separated from the entrained solid catalyst, and the separated catalyst is returned to the reaction zone. The gas stream enters a gas collection chamber 1 and is then discharged from a first material outlet 11.

[0095] In the following examples 1-6, the tubular distributor 4 has four branch pipes 13, each branch pipe 13 is connected to 14 branch pipes 14, 1112 nozzles are set, and the inlet flow rate of the main pipe 12 is 3.08×10 4 m 3 The unevenness data in the examples are obtained by computational fluid dynamics (CFD) analysis using the operating conditions and structural dimensions of the tubular distributor given in each example.

[0096] Example 1

[0097] Each branch pipe 13 of the tubular distributor 4 is composed of three sections of circular pipes with different diameters connected together. Along the flow direction in the pipe, the diameter ratio of the three sections of circular pipes is 1:0.75:0.35, and the corresponding three sections of pipes account for the total length of the branch pipe 13 in the ratio of 0.8:0.1:0.1 respectively; the branch pipe 14 is connected to the branch pipe 13 through a rectifying component 16; the angle α between the outer contour of the straight tube shell 17 and the main flow direction 15 of the branch pipe 13 is 160°, the outer contour line of the rectifying component's different diameter curved tube shell is an arc, and the cross-section of the internal flow channel of the rectifying component is elliptical; swirl nozzles are installed at equal intervals on the branch pipe 14, wherein the nozzle feed port 21 is along the inner side of the shell. The circumferential wall extends in the involute direction, has a square cross-section, and an angle β of 60°. The height and diameter of the cylindrical upper swirl chamber of the nozzle are the same, the top diameter of the lower swirl conical chamber is the same as the bottom end of the upper swirl chamber, and the ratio of the bottom diameter to the top diameter is 0.25; the central column 24 of the swirl nozzle is a cylinder of equal diameter, and the connection surface between the central column of the swirl nozzle and the guide body is flush with the lower end surface of the lower swirl conical chamber. The ratio of the diameter of the central column 24 to the bottom diameter of the swirl chamber is 0.71. The longitudinal cross-section of the guide body 26 is spindle-shaped, and the ratio of its height to maximum diameter is 1.5; the ratio of the vertical distance between the tubular distributor 4 and the gas distribution plate 7 to the height of the reaction chamber 2 is 0.03.

[0098] The reaction raw materials in the fluidized bed reactor are m-xylene, ammonia and air in a molar ratio of 1:5.8:23.4, the reaction temperature is 415°C, the pressure is 0.05 MPa, the gas superficial velocity is 0.4 m / s, the heterogeneity is 0.033, and the yield of isophthalonitrile is 83.1%.

[0099] Example 2

[0100] The branch pipe 13 of the tubular distributor 4 is composed of three sections of circular pipes with different diameters. Along the flow direction in the pipe, the ratio of the diameters of the three sections of circular pipes is 1:0.75:0.25. At the same time, the ratio of the three sections of pipes to the total length of the branch pipe 13 is 0.7:0.15:0.15. The branch pipe 14 is connected to the branch pipe 13 by a rectifying component 16. The angle α between the outer contour of the straight pipe shell 17 and the main flow direction 15 of the branch pipe 13 is 135°. The outer contour line of the rectifying component's different diameter curved pipe shell is an elliptical arc. The flow path inside the flow component has an elliptical cross-section. Swirl nozzles are evenly spaced on the branch pipe 14. The nozzle feed port 21 extends along the spiral line of the inner circumferential wall of the shell, has a square cross-section, and an angle β of 120°. The height and diameter of the nozzle's cylindrical upper swirl chamber are the same, and the top diameter of the lower swirl conical chamber is the same as the bottom of the upper swirl chamber, with a bottom-to-top diameter ratio of 0.25. The swirl nozzle's central column is a tapered column with a ratio of the large-end diameter to the small-end diameter of 1.25. The connection surface between the central column and the guide body is 0.05 times the bottom diameter of the central column at the lower end of the lower swirl conical chamber. The guide body 26 has a spindle-shaped longitudinal cross-section. The ratio of the vertical distance between the tubular distributor 4 and the gas distribution plate 7 to the height of the reaction chamber 2 is 0.06.

[0101] The reaction raw materials in the fluidized bed reactor are m-xylene, ammonia and air in a molar ratio of 1:5.5:22.1, the reaction temperature is 415°C, the pressure is 0.05 MPa, the gas superficial velocity is 0.4 m / s, the heterogeneity is 0.04, and the yield of isophthalonitrile is 82.8%.

[0102] Example 3

[0103] The branch pipe 13 of the tubular distributor 4 is composed of three connected circular tubes of varying diameters. Along the flow direction within the pipe, the diameters of the three sections are in a ratio of 1:0.75:0.35. The corresponding lengths of the three sections relative to the total length of the branch pipe 13 are 0.8:0.1:0.1, respectively. The branch pipe 14 is connected to the branch pipe 13 via a flow straightening member 16. The outer contour of the straight tube shell 17 forms an angle α of 120° with the main flow direction 15 of the branch pipe 13. The outer contour of the flow straightening member's curved tube shell is an arc. The flow path within the flow straightening member is elliptical in cross-section. Swirl nozzles 19 are arranged at equal intervals on the branch pipe 14. The nozzle inlet is square in cross-section and extends tangentially to the inner circumferential wall of the shell. The height and diameter of the cylindrical upper swirl chamber of the nozzle are the same, the top diameter of the lower swirl conical chamber is the same as the bottom end of the upper swirl chamber, and the ratio of the bottom diameter to the top diameter is 0.25; the central column of the swirl nozzle is a cylinder of equal diameter, and the connection surface between the central column of the swirl nozzle and the guide body is flush with the lower end surface of the lower swirl conical chamber. The ratio of the diameter of the central column 24 to the bottom diameter of the swirl chamber is 0.71. The longitudinal cross-section of the guide body 26 is spindle-shaped, and the ratio of its height to maximum diameter is 1.5; the ratio of the vertical distance between the tubular distributor 4 and the gas distribution plate 7 to the height of the reaction chamber 2 is 0.09.

[0104] The reaction raw materials in the fluidized bed reactor were toluene, ammonia and air in a molar ratio of 1:3.5:12.5, the reaction temperature was 405°C, the pressure was 0.1 MPa, the gas superficial velocity was 0.5 m / s, the heterogeneity was 0.03, and the yield of benzonitrile was 84.5%.

[0105] Example 4

[0106] Unlike Example 1, the branch pipe 13 of the tubular distributor 4 is composed of two connected circular tubes of different diameters. Along the flow direction within the tube, the diameter ratio of the two tubes is 1:0.45; The corresponding length ratio of the two tubes to the total length of the branch pipe is 0.7:0.3. The connection surface between the central column 24 of the swirl nozzle and the flow guide 26 is lower than the lower end surface of the lower swirl conical cavity by 0.05 times the diameter of the central column's bottom end. The included angle β is 130°.

[0107] The reaction raw materials in the fluidized bed reactor are m-xylene, ammonia and air in a molar ratio of 1:7:25.4, the reaction temperature is 415°C, the pressure is 0.05 MPa, the gas superficial velocity is 0.4 m / s, the heterogeneity is 0.05, and the yield of isophthalonitrile is 81.6%.

[0108] Example 5

[0109] The difference from Example 1 is that the branch pipe 14 of the tubular distributor 4 is a circular pipe directly connected to the branch pipe 13 without passing through the rectifying component 16 but directly connected to each other vertically; the unevenness is 0.062, and the yield of isophthalonitrile is 79.5%.

[0110] Example 6

[0111] The difference from Example 1 is that the branch pipe 13 of the tubular distributor 4 is a circular pipe with a constant diameter; the unevenness is 0.073, and the yield of isophthalonitrile is 78.4%.

[0112] Comparative Example 1

[0113] The difference from Example 1 is that the tubular distributor 4 does not use the nozzle of the present invention but uses a standard tubular insert nozzle in the prior art; the unevenness is 0.092, and the yield of isophthalonitrile is 76.1%.

[0114] Comparative Example 2

[0115] The difference from Example 1 is that, as shown in FIG10 , a tubular distributor in the prior art is used, wherein the branch pipes and the branch pipes are all circular pipes and are vertically connected to each other, and standard tubular insert nozzles are arranged at equal intervals on the branch pipes.

[0116] The reaction raw materials in the fluidized bed reactor are m-xylene, ammonia and air, the heterogeneity is 0.13, and the yield of isophthalonitrile is 73.5%.

[0117] Comparative Example 3

[0118] The difference from Example 3 is that, as shown in FIG10 , a tubular distributor in the prior art is used, wherein the branch pipes and the branch pipes are all circular pipes and are vertically connected to each other, and standard tubular insert nozzles are arranged at equal intervals on the branch pipes.

[0119] The reaction raw materials in the fluidized bed reactor are toluene, ammonia and air, the heterogeneity is 0.096, and the yield of benzonitrile is 77.5%.

[0120] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention may be subjected to various simple modifications, including combining the specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A swirl nozzle, characterized in that: The swirl nozzle (19) comprises: A shell, wherein the shell defines a swirl chamber, the swirl chamber comprises an upper swirl chamber (22) and a lower swirl chamber (23), a bottom end of the lower swirl chamber (23) is formed with a bottom end opening, and the shell is provided with a nozzle feed port (21) communicating with the upper swirl chamber (22); A central column (24) is arranged in the swirl chamber, the bottom end of the central column (24) extends toward the bottom opening of the lower swirl chamber (23) and is connected to a guide body (26), and a nozzle discharge port (25) with an annular gap is formed between the guide body (26), the bottom end of the central column (24) and the bottom opening of the lower swirl chamber (23); The material entering from the nozzle feed port (21) can flow along the inner peripheral wall of the swirl chamber to form a downward swirl around the central column (24), and the downward swirl is ejected through the nozzle discharge port (25).

2. The swirl nozzle according to claim 1, characterized in that: The guide body (26) comprises a gradually expanding section whose cross section gradually increases in the axial downward direction, and the small end of the gradually expanding section is connected to the bottom end of the central column (24); Preferably, the gradually expanding section is configured to be truncated cone-shaped, and the connection surface between the gradually expanding section and the center column (24) is located above, below or flush with the bottom end surface of the lower vortex chamber (23), and the distance between the connection surface and the bottom end surface of the lower vortex chamber (23) in the height direction is 0-0.1 times the diameter of the bottom end of the center column (24).

3. The swirl nozzle according to claim 2, characterized in that: A tapered section whose cross section gradually decreases axially downward is provided below the gradually expanding section; the tapered section is preferably provided in a conical shape; Preferably, a buffer section is provided between the gradually contracting section and the gradually expanding section, and the buffer section is preferably cylindrical or drum-shaped with a raised center.

4. The swirl nozzle according to claim 1, characterized in that: The nozzle feed port (21) is connected to the peripheral wall of the shell and communicates with the upper swirl chamber (22), and the nozzle feed port (21) extends along the tangent direction, involute direction or helical direction of the inner peripheral wall of the shell; and / or An angle β between a first inner wall (211) of the nozzle feed port (21) and an inner peripheral wall of the shell and a line connecting the center of the shell and the first inner wall (211) is 60°-120°; and / or The normal cross-section of the nozzle feed port (21) in the material flow direction is one of rectangular, circular or elliptical; and / or The upper swirl chamber (22) is a cylindrical or truncated cone-shaped chamber; Preferably, the ratio of the height of the cylindrical cavity and / or the truncated cone cavity to the diameter of the circle at the middle position is 0.1-10; More preferably, the ratio of the maximum diameter to the minimum diameter of the truncated cone cavity is 0.1-10; and / or The lower swirl chamber (23) is configured as a conical chamber, the bottom end of the conical chamber is formed with the bottom end opening, the top end diameter of the conical chamber is the same as the bottom end diameter of the upper swirl chamber (22), and the ratio of the bottom end diameter to the top end diameter of the conical chamber is 0.1-10.

5. A tubular distributor, characterized in that: The tubular distributor (4) comprises a plurality of branch pipes (13) and a plurality of branch pipes (14) connected to each branch pipe (13), and each branch pipe (14) is provided with a plurality of swirl nozzles (19) according to any one of claims 1 to 4.

6. The tubular distributor according to claim 5, characterized in that: The connecting end between the branch pipe (14) and the branch pipe (13) is provided with a rectifying component (16) capable of strengthening the distribution of the flow.

7. The tubular distributor according to claim 5 or 6, characterized in that: The tubular distributor (4) has a tree-shaped tubular distribution structure; a plurality of branch pipes (14) are arranged on both sides of each branch pipe (13); Preferably, the branch pipe (14) is arranged to extend radially along the branch pipe (13), one end of the branch pipe (14) is connected to the side of the branch pipe (13) through a rectifying component (16), and the other end is arranged to be closed; and / or The cross section of the branch pipe (14) is circular, elliptical or rectangular.

8. The tubular distributor according to claim 5 or 6, characterized in that: Along the main flow direction (15) of the logistics, the branch pipe (13) is a tapered pipe with a gradually decreasing lumen cross section; Preferably, the branch pipe (13) is a round pipe, and the ratio of the diameter of the small end to the diameter of the large end of the round pipe is 0.1-0.9; More preferably, the branch pipe (13) is composed of multiple sections of circular pipes with different diameters connected end to end; Further preferably, the length of each section of the circular tube accounts for 0.05-0.95 of the total length of the branch tube (13); And / or the ratio of the minimum diameter to the maximum diameter of the branch pipe (13) is 0.1-0.

9.

9. The tubular distributor according to any one of claims 5 to 8, characterized in that: The tubular distributor (4) further comprises a main pipe (12), a plurality of branch pipes (13) are provided, and the plurality of branch pipes (13) are radially arranged on the side of the main pipe (12), and one end of the branch pipe (13) is connected to the main pipe (12), and the other end is set to be closed.

10. The tubular distributor according to claim 5 or 6, characterized in that: The rectifying component (16) is a pipe with a variable diameter, the large end of the rectifying component (16) is radially connected to the branch pipe (13), and the small end is connected to the branch pipe (14); Preferably, the tube shell surrounding the rectifying member (16) is composed of a straight tube shell (17) and a different-diameter curved tube shell (18); More preferably, The outer contour of the straight tube shell (17) is aligned with the main flow direction (15) of the branch pipe (13). The angle α is 90°-175°; and / or Along the flow direction in the rectifying component (16), the profile of the different-diameter curved tube shell (18) is in the shape of a circular arc, an elliptical arc or a parabola.

11. A fluidized bed reaction device, characterized in that: The fluidized bed reaction device comprises a reaction chamber (2), a material distributor is arranged in the reaction chamber (2), and the material distributor comprises a tubular distributor (4) according to any one of claims 5 to 10; Preferably, The material distributor comprises at least one of the tubular distributors (4) and a gas distribution plate (7); More preferably, the ratio of the vertical distance between the gas distribution plate (7) and the adjacent tubular distributor (4) to the height of the reaction chamber (2) is 0.01-0.

1.

12. Use of the swirl nozzle according to any one of claims 1 to 4, the tubular distributor according to any one of claims 5 to 10, or the fluidized bed reaction device according to claim 11 in hydrocarbon ammoxidation, catalytic cracking, nitrobenzene hydrogenation, coal gasification, or trichlorosilane cold hydrogenation reaction.

13. A method for ammoxidation of hydrocarbons, characterized in that: The method adopts the fluidized bed reaction device according to claim 11, wherein the material distributor comprises at least one of the tubular distributors (4) and a gas distribution plate (7); Preferably, the method comprises: The raw material containing the hydrocarbon source and the ammonia source enters the reaction chamber (2) through the tubular distributor (4), and the oxygen-containing gas enters the reaction chamber (2) through the gas distribution plate (7); In the reaction chamber, the raw material containing the hydrocarbon source and the ammonia source is contacted and reacted with the oxygen-containing gas. Preferably, the raw material containing the hydrocarbon source and the ammonia source is contacted and reacted with the oxygen-containing gas in reverse direction.

14. The method according to claim 13, wherein: The unevenness of the ejection flow rate of the tubular distributor (4) is 0-0.35; and / or The molar ratio of the hydrocarbon source in terms of hydrocarbon groups, the ammonia source in terms of amino groups and the oxygen-containing gas in terms of oxygen molecules is 1:(1-10):(10-40); Preferably, the hydrocarbon source comprises hydrocarbons and / or hydrocarbon derivatives, more preferably comprises at least one of toluene, p-chlorotoluene, o-chlorotoluene, o-xylene, m-xylene, p-xylene, dichlorotoluene, trichlorotoluene and 4-nitro-o-xylene; and / or The ammonia source is ammonia gas; and / or The contact conditions include: reaction temperature of 300-500° C., pressure of 0.01-0.2 MPa, and gas superficial velocity of 0.1-0.8 m / s.

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