Gas distribution plate, fluidized bed reactor, and method for ammoxidation

Abstract

The gas distribution plate (6) includes a metal plate, a central opening, and peripheral openings. The ratio D1 / D1' of the opening diameter D1 of the central opening to the opening diameter D1' of the peripheral opening satisfies the relationship 1.10≧D1 / D1'>1.00. A fluidization device including the gas distribution plate and its use in an oxidation or ammoxidation process are also provided.

Description

Detailed Description of the Invention

[0001] 〔Technical Field〕 The present invention relates to a gas distribution plate, and in particular, to an air distribution plate. Further, the present invention relates to a fluidization device including the gas distribution plate, and an oxidation process or an ammoxidation process using the same.

[0002] 〔Background Art〕 Acrylonitrile is produced worldwide by propylene ammoxidation. In the production process, there are specific requirements for the ratio between raw materials. For example, the ratio of ammonia to propylene is set to 1 to 1.5, and the ratio of air to propylene is set to 8.5 to 10.5. In fact, such ratios are within the explosion limit (flammable limit) range of propylene-ammonia. In this production process, the three raw materials are not introduced into the reaction layer (reaction bed) after mixing, but are introduced into the reaction layer separately. The mixture of propylene and ammonia is introduced into the reaction layer through one distributor, and air is introduced into the reaction layer through another distributor. Propylene, ammonia and air are preferably subjected to an ammoxidation reaction under the action of a catalyst. As a result, the explosion concentration range of the feed gas can be avoided.

[0003] As shown in FIG. 1, in the ammoxidation fluidized bed reactor 1, each component is an air inlet 8, a gas distribution plate (also referred to as an air distribution plate) 6, a propylene-ammonia supply distributor 10, a reactor wall surface 4, and a heat removal water pipe 7. Air is introduced into the reactor through the air inlet 8, passes through the gas distribution plate 6, and is uniformly mixed with the propylene-ammonia feed gas introduced into the reactor through the supply distributor 10, and then passed through the catalyst layer (catalyst bed). Thereby, the ammoxidation reaction can be carried out.

[0004] The gas distribution plate is one of the important internal components of an acrylonitrile fluidized bed reactor. And the quality of the design of the gas distribution plate directly affects the fluidity of the fluidized bed and the operating performance of the reactor. A typical gas distribution plate of an acrylonitrile fluidized bed has the shape of a plate with holes (orifices) and is equipped with short pipes. Specifically, the gas distribution plate comprises a continuous metal plate and gas distribution plate nozzles. Air flows into the nozzles through the holes at the ends of the nozzles, and then flows into the reaction layer through the nozzles of the air distribution plate. The feed gas and air are guided by each nozzle of the gas distribution plate and diffused from the bottom to the top of the reaction layer.

[0005] In the case of an acrylonitrile fluidized bed reactor, the pressure loss of the distributor may be affected by changes in the structure of the gas distribution plate. To ensure a uniform distribution of the gas flow and avoid significant non-uniformities caused by certain fluctuations or load reductions, the distributor is usually required to have a sufficient pressure loss.

[0006] The document "Research on Capacity Expansion and Modification of Acrylonitrile Plants (Contemporary Chemical Industry, volume 34, No. 5)" discloses that the pressure loss of the gas distribution plate is about 60% of the pressure loss of the reaction layer. The pressure loss is considered to result in a uniform gas distribution and an orifice passing velocity that does not cause severe erosion of the catalyst.

[0007] GB1265770A discloses a fluidized bed reactor. In the fluidized bed reactor, the influence of the wall effect can be eliminated by fluidizing the catalyst deposited near the reactor wall together with the fluid by means of an annular distribution pipe arranged on the distribution plate at a position close to the reactor wall and concentric with the distribution plate.

[0008] Disclosure of the Invention The inventors of the present invention have found the following. As the production scale of acrylonitrile increases, the reactor diameter also increases. Nevertheless, when using the pressure loss of the gas distribution plate described in "Research on Capacity Expansion and Modification of Acrylonitrile Plants", the fluidity near the reactor wall deteriorates due to the wall boundary effect, and ultimately the reaction results will be affected. Therefore, the existing pressure loss design parameters of the gas distribution plate are not suitable for the design requirements of large-scale fluidized bed reactors.

[0009] The inventors of the present invention have also found the following. In currently widely used fluidized bed reactors, the supply gas and air are supplied separately, and their uniform mixing is achieved by the supply distributor and the gas distribution plate. Therefore, if the wall effect is removed by blowing air in the opposite direction to the gas distribution plate using the distribution pipe disclosed in GB1265770A, it will inevitably have an adverse effect on the dispersion effect of the gas distribution plate, and ultimately affect the mixing of air and the supply gas. Furthermore, the separate arrangement of the distribution pipes not only increases the equipment cost, but also complicates the internal structure of the reactor and may have an adverse effect on the fluidity.

[0010] The inventors of the present invention have also found the following. In the acrylonitrile fluidized bed, there exist a bubble phase and a particulate phase. In aggregative fluidization, the gas mainly moves upward through the reaction layer in the form of bubbles. And the movement of the bubbles in the reaction layer plays an important role in heat conduction, mass transfer, and chemical reactions. After the gas passes through the distributor, bubbles can be formed. Bubbles are formed at the moment when the gas is introduced into the reaction layer through the openings of the gas distribution plate. The size and shape of the bubbles are related to the properties of the catalyst particles, the properties of the gas, the diameter of the openings, and the flow rate of the gas passing through the openings. The catalyst content in the bubble phase is relatively low and may account for about 1% of the total amount of the catalyst in the reaction layer. There may be an exchange of substances between the gas and the contained catalyst in the bubble phase and the catalyst and the contained gas in the particulate phase. As a result, the gas in the particulate phase may enter the bubbles, while on the other hand, a part of the gas in the bubbles may penetrate through the boundaries of the bubbles and into the catalyst particles. Small bubbles are more favorable for mass transfer than large bubbles.

[0011] The inventors of the present invention have also found the following. Initial bubble formation, which is related to the flow rate of the gas passing through the openings, at a position slightly above the gas distribution plate is important for the good fluidity of the acrylonitrile fluidized bed reactor. A typical gas distribution plate for an acrylonitrile fluidized bed is a perforated metal plate. And it requires the same and smooth velocity of the gas passing through each opening in order to achieve the same fluidity per unit cross-section at a position slightly above the gas distribution plate.

[0012] The inventors of the present invention have also found the following. The fluid velocity between the position near the reactor wall and the reactor center has a certain gradient due to the influence of physical factors such as the viscosity during fluid movement and wall friction. Therefore, the liquid near the reactor wall is in a relatively stationary state, and the catalyst near the reactor wall is in a state of sedimenting downward relative to the catalyst at the center of the reactor. In other words, the catalyst at the center of the reactor has better fluidity than the catalyst near the reactor wall. The fluidity near the reactor wall may be deteriorated by the wall boundary effect. As a result, propylene ammoxidation may not reach the optimal reaction state, and the propylene conversion rate in the region near the reactor wall may decrease, thereby affecting the reaction result of the entire reactor. This result cannot meet the requirement of enlarging the reactor. Therefore, although it may not be possible to reduce the pressure loss of the gas distribution plate, it is possible to reduce the influence of the wall effect on the fluidity near the reactor wall, suppress the decrease in the fluidity of the catalyst near the reactor wall, and develop a gas distribution plate that can meet the requirement of high-speed and uniform mixing of the gas from the distribution plate / distributor at the position near the reactor wall, which is required in this technical field.

[0013] The inventors of the present invention have found the following through extensive research and experiments. The fluidity near the reactor wall can be improved by appropriately reducing the inner diameter of the nozzle near the reactor wall and increasing the flow velocity of the air passing through the opening. As a result, the conversion rate of the raw material at the corresponding position can be increased, and thereby, the yield of acrylonitrile in the entire reaction unit can be increased accordingly.

[0014] The present invention has been achieved based on these findings.

[0015] Specifically, the present invention relates to the following aspects: 1. A gas distribution plate (particularly a flat metal plate), an opening provided in the central region of the metal plate (referred to as a central opening), and an opening provided in the peripheral region of the metal plate (referred to as a peripheral opening), wherein the ratio D1 / D1' of the opening diameter D1 (unit: mm) of the central opening to the opening diameter D1' (unit: mm) of the peripheral opening satisfies the relationship 1.10 ≥ D1 / D1' > 1.00, preferably 1.08 ≥ D1 / D1' > 1.00, more preferably 1.06 ≥ D1 / D1' ≥ 1.01. (Particularly an air distribution plate or an air distribution plate for an ammoxidation fluidized bed reactor).

[0016] 2. The opening diameters D1 of each of the central openings are the same as or different from each other (preferably the same as each other), each being 16 to 60 mm, preferably 20 to 56 mm, more preferably 22 to 52 mm, and / or the opening diameters D1' of each of the peripheral openings are the same as or different from each other (preferably the same as each other), each being 15 to 58 mm, preferably 19 to 54 mm, more preferably 21 to 50 mm. The gas distribution plate according to any one of the foregoing or subsequent aspects.

[0017] 3. The number of the central openings is 16 to 100 (preferably 17 to 64, more preferably 18 to 44) per square meter of the central region, and / or the number of the peripheral openings is 2 to 50 (preferably 3 to 44, more preferably 4 to 25) per square meter of the peripheral region, and / or the number of the central openings is 70% to 99% (preferably 75% to 98%, more preferably 80% to 95%) of the total number of openings of the metal plate. The gas distribution plate according to any one of the foregoing or subsequent aspects.

[0018] 4. The gas distribution plate according to any one of the foregoing or subsequent aspects, wherein the number of the central openings per unit area of the central region is substantially the same.

[0019] 5. The central opening and / or the peripheral opening are arranged in a substantially square, equilateral triangle, regular rhombus, or concentric circle shape, preferably in a substantially square or equilateral triangle shape. The gas distribution plate according to any one of the foregoing or subsequent aspects.

[0020] 6. The distance between any two adjacent said central openings is the same or different from each other (preferably the same as each other), each being 100 to 300 mm, preferably 125 to 285 mm, more preferably 150 to 270 mm, and / or the distance between any two adjacent said peripheral openings is the same or different from each other (preferably the same as each other), each being 100 to 300 mm, preferably 125 to 285 mm, more preferably 150 to 270 mm. The gas distribution plate according to any of the foregoing or subsequent aspects.

[0021] 7. The metal plate is substantially circular, the diameter of the circle is 5 to 29 m, preferably 7 to 20 m, and the thickness is 5 to 40 mm, preferably 10 to 35 mm. The gas distribution plate according to any of the foregoing or subsequent aspects.

[0022] 8. Let the linear distance between any point on the outer periphery of the metal plate and the center point of the metal plate be R (especially the radius), and the region surrounded by all the points on the metal plate at a linear distance r from the center point be the central region, and the region between the central region and the outer periphery be the peripheral region. The value of r / R is 0.2 to 0.99, preferably 0.5 to 0.9, more preferably 0.7 to 0.85. The gas distribution plate according to any of the foregoing or subsequent aspects.

[0023] 9. At least one (preferably all) of the central openings has a nozzle (referred to as a central nozzle), and the central nozzle is a hollow tube with the starting end of the central nozzle inserted into the central opening, vertically connected to the metal plate, coaxial with the central opening, and the end of the central nozzle has a hole (referred to as a central hole), and / or at least one (preferably all) of the peripheral openings has a nozzle (referred to as a peripheral nozzle), and the peripheral nozzle is a hollow tube with the starting end of the peripheral nozzle inserted into the peripheral opening, vertically connected to the metal plate, coaxial with the peripheral opening, and the end of the peripheral nozzle has a hole (referred to as a peripheral hole). The gas distribution plate according to any of the foregoing or subsequent aspects.

[0024] 10. The opening diameters d of each of the central holes are the same as or different from each other (preferably the same as each other), each being 5 to 20 mm, preferably 7 to 18 mm, more preferably 10 to 16 mm, and / or the opening diameters d' of each of the peripheral holes are the same as or different from each other (preferably the same as each other), each being 5 to 20 mm, preferably 7 to 18 mm, more preferably 10 to 16 mm, and / or the opening diameter d of the central hole is the same as or different from the opening diameter d' of the peripheral hole, and / or the gas distribution plate according to any one of the foregoing or subsequent aspects satisfying the relationship of 1.10 ≥ d / d' ≥ 1.00 (preferably 1.04 ≥ d / d' ≥ 1.00).

[0025] 11. The central nozzle and / or the peripheral nozzle has an injection angle α of 2° to 20°, preferably 4° to 17°, more preferably 5° to 14° in the gas distribution plate according to any one of the foregoing or subsequent aspects.

[0026] 12. The length of the central nozzle and / or the peripheral nozzle is 80 to 300 mm, preferably 100 to 270 mm, more preferably 120 to 240 mm in the gas distribution plate according to any one of the foregoing or subsequent aspects.

[0027] 13. When the opening diameter of the central hole is d (unit: mm), the opening diameter of the peripheral hole is d' (unit: mm), the opening diameter of the central opening is D1 (unit: mm), and the opening diameter of the peripheral opening is D1' (unit: mm), then (d' / D1') / (d / D1) ≥ 1, preferably (d' / D1') / (d / D1) = 1 to 1.25, (d' / D1') / (d / D1) = 1 to 1.20, or (d' / D1') / (d / D1) = 1.01 to 1.10 in the gas distribution plate according to any one of the foregoing or subsequent aspects.

[0028] 14. The inner diameter D2 of each of the central nozzles is the same as or different from each other (preferably the same as each other), and is respectively 6 to 50 mm, preferably 10 to 47 mm, more preferably 12 to 44 mm, and / or the inner diameter D2' of each of the peripheral nozzles is the same as or different from each other (preferably the same as each other), and is respectively 5 to 48 mm, preferably 9 to 45 mm, more preferably 11 to 42 mm. The gas distribution plate according to any of the foregoing or subsequent aspects.

[0029] 15. A gas distribution plate comprising a metal plate, a central opening provided in the central region of the metal plate, and a peripheral opening provided in the peripheral region of the metal plate. At least one (preferably all) of the central openings has a nozzle (referred to as a central nozzle). The central nozzle is a hollow tube with the starting end of the central nozzle inserted into the central opening, vertically connected to the metal plate, coaxial with the central opening, and the terminal end of the central nozzle has a hole (referred to as a central hole). At least one (preferably all) of the peripheral openings has a nozzle (referred to as a peripheral nozzle). The peripheral nozzle is a hollow tube with the starting end of the peripheral nozzle inserted into the peripheral opening, vertically connected to the metal plate, coaxial with the peripheral opening, and the terminal end of the peripheral nozzle has a hole (referred to as a peripheral hole). Let the opening diameter of the central hole be d (unit: mm), the opening diameter of the peripheral hole be d' (unit: mm), the opening diameter of the central opening be D1 (unit: mm), and the opening diameter of the peripheral opening be D1' (unit: mm). Then, (d' / D1') / (d / D1) ≧ 1, preferably (d' / D1) / (d / D1) = 1 to 1.25, (d' / D1') / (d / D1) = 1 to 1.20, or (d' / D1') / (d / D1) = 1.01 - 1.10.

[0030] 16. A fluidization device (preferably a fluidized bed reactor) comprising at least one housing, a fluidization device chamber defined by the housing, and a gas distribution plate disposed in the fluidization device chamber, wherein the gas distribution plate is the gas distribution plate according to any of the foregoing or subsequent aspects.

[0031] 17. The fluidization device chamber has a layer of solid particles (preferably catalyst particles), and the pressure loss ΔPd (unit: MPa) of the gas distribution plate is 62 to 120%, preferably 65 to 115%, more preferably 68 to 110% of the pressure loss ΔPb (unit: MPa) of the layer of solid particles. The fluidization device according to any one of the foregoing or subsequent aspects.

[0032] 18. Using the gas distribution plate according to any one of the foregoing or subsequent aspects as an oxidation gas (preferably air or oxygen) distribution plate, or in the fluidized bed reactor according to any one of the foregoing or subsequent aspects, to produce an oxide or an amino oxide (preferably propylene oxide or acrylonitrile), a step of subjecting a feedstock (preferably waste or a hydrocarbon feedstock, more preferably C 2~8 olefin or propylene) to an oxidation reaction or an ammoxidation reaction using an oxidation gas (preferably air or oxygen). An oxidation or ammoxidation method (process).

[0033] 19. A method for distributing a gas, comprising a step of delivering the gas from one side to the other side through the gas distribution plate according to any one of the foregoing or subsequent aspects while making the flow rate of the gas passing through the peripheral opening equal to or higher than the flow rate of the gas passing through the central opening.

[0034] 〔Brief Description of the Drawings〕 FIG. 1 is a schematic diagram of a fluidized bed reactor of the present invention.

[0035] FIGS. 2A and 2B are schematic diagrams of the arrangement of the openings of the gas distribution plate of the present invention.

[0036] FIGS. 3 and 4 are schematic diagrams of the nozzles of the present invention.

[0037] FIG. 5 is a schematic diagram of the pressure monitoring of the gas distribution plate of the present invention.

[0038] 〔Explanation of Reference Numerals〕 1. Fluidized bed reactor 2. Hole of gas distribution plate 3. Nozzle of gas distribution plate 4. Wall of the fluidized bed reactor 5. Pressure measurement port above the distributor plate of the fluidized bed reactor 6. Gas distributor plate 7. Heat removal water pipe 8. Air inlet of the fluidized bed reactor 9. Pressure measurement port inside the conical part of the fluidized bed reactor 10. Propylene-ammonia supply distributor 〔Technical effects〕 By using the gas distributor plate of the present invention, the effect of uniform gas distribution can be achieved.

[0039] By using the fluidization device of the present invention, good fluidity can be achieved.

[0040] By using the gas distributor plate of the present invention, the maximum utilization rate of the catalyst can be obtained, and the reduction of the unused part (dead zone) of the catalyst can be achieved.

[0041] By monitoring the pressure loss ΔPd of the gas distributor plate of the present invention, the operating state of the gas distributor plate can be monitored in real time.

[0042] 〔Detailed description of the invention〕 Hereinafter, the present application will be described in detail with reference to the embodiments of the present application. However, it should be noted that the scope of the present application is defined by the appended claims and is not limited by these embodiments.

[0043] All publications, patent applications, patents, and other references cited in this specification are incorporated by reference in their entirety. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the art. In case of conflict, the content described in this specification including the definitions shall prevail.

[0044] Note that the materials, substances, methods, processes, devices, components, etc. described in this specification are modified by expressions such as "known to those skilled in the art" and "known in the art". The above-mentioned materials, substances, methods, processes, devices, components, etc. include not only those that have been conventionally used in the art at the time of filing of this application, but also those that are not currently commonly used, provided that it is generally known in the art that they are suitable for the same purpose.

[0045] In the context of this specification, the term "flat plate" includes not only what is substantially flat, but also what those skilled in the art would normally understand to be a flat plate.

[0046] In the context of this application, the term "substantially" means that deviations such as within ±10%, within ±5%, within ±1%, within ±0.5%, or within ±0.1% are allowed, which are considered acceptable or reasonable to those skilled in the art.

[0047] In the context of this application, unless otherwise specified, all percentages, ratios, proportions, etc. are expressed by weight, and all given pressures are gauge pressures.

[0048] In the context of this application, any two or more embodiments of this application can be arbitrarily combined, and the resulting technical solution forms part of the initial disclosure of this application and falls within the scope of this application.

[0049] According to one embodiment of the present invention, the present invention relates to a gas distribution plate. Here, as the gas distribution plate, an air distribution plate, particularly an air distribution plate used in an ammonia oxidation fluidized bed reactor or an acrylonitrile fluidized bed reactor, is particularly mentioned. As is known, the gas distribution plate typically has a flat plate shape with holes.

[0050] According to an embodiment of the present invention, the gas distribution plate includes a metal plate, an opening provided in the central region of the metal plate (referred to as the central opening), and an opening provided in the peripheral region of the metal plate (referred to as the peripheral opening). These openings are through-holes that extend through the metal plate from the upper surface to the lower surface of the metal plate, and are provided for introducing gas into the fluidization device or the layer of solid particles. In particular, let the linear distance between any point on the outer periphery of the metal plate and the center point of the metal plate be R, and the region surrounded by all points on the metal plate having a linear distance r from the center point be referred to as the central region, and the region between the central region and the outer periphery be referred to as the peripheral region. Here, when the metal plate is substantially circular, R is the radius of the metal plate and r is the radius of the central region.

[0051] Especially in the case of application to ammoxidation or an acrylonitrile fluidized bed reactor, it is known that the metal sheet is a flat metal sheet. When a flat metal plate is used as the metal plate, a fluid velocity higher than the fluid velocity at the center of the reactor can be obtained in the vicinity of the reactor wall. That is, the flow velocity of the gas passing through the peripheral opening (hereinafter referred to) is equal to or higher than the flow velocity of the gas passing through the central opening (hereinafter referred to). Thereby, the fluidity of the catalyst in the vicinity of the reactor wall can be improved. Here, the velocity is typically characterized by a linear velocity of about 6 m / s to about 25 m / s, but the present invention is not limited thereto. Furthermore, the flow velocity can be easily obtained by directly measuring the gas velocity at the discharge port of the corresponding opening.

[0052] According to an embodiment of the present invention, uniform distribution of gas or air can be achieved by delivering gas from one side to the other side through the gas distribution plate. Here, as described above, the flow velocity of the gas passing through the peripheral opening is equal to or higher than the flow velocity of the gas passing through the central opening.

[0053] According to an embodiment of the present invention, the value of r / R is 0.2 to 0.99, preferably 0.5 to 0.9, more preferably 0.7 to 0.85.

[0054] According to an embodiment of the present invention, the ratio D1 / D1' of the opening diameter D1 (unit: mm) of the central opening to the opening diameter D1' (unit: mm) of the peripheral opening satisfies the relationship of 1.10 ≥ D1 / D1' > 1.00, preferably 1.08 ≥ D1 / D1' > 1.00, and more preferably 1.06 ≥ D1 / D1' ≥ 1.01.

[0055] According to an embodiment of the present invention, the opening diameters D1 of the central openings are the same as or different from each other, preferably the same as each other. And the opening diameter D1 of each central opening is 16 to 60 mm, preferably 20 to 56 mm, and more preferably 22 to 52 mm.

[0056] According to an embodiment of the present invention, the opening diameters D1' of the peripheral openings are the same as or different from each other, preferably the same as each other. And the opening diameter D1' of each peripheral opening is 15 to 58 mm, preferably 19 to 54 mm, and more preferably 21 to 50 mm.

[0057] According to an embodiment of the present invention, the inventors of the present application have found through theoretical calculations and experimental verifications on initial bubbles that the number of central openings per square meter of the area of the central region is 16 to 100, preferably 17 to 64, or 18 to 44. In order to achieve a more uniform introduction of gas, it is preferable that the central region has the same number of central openings per unit cross-sectional area.

[0058] According to an embodiment of the present invention, the number of central openings is 70 to 99% of the total number of openings of the metal sheet, preferably 75 to 98%, and more preferably 80 to 95%.

[0059] According to an embodiment of the present invention, the inventors of the present application have found through theoretical calculations and experimental verifications on initial bubbles that the number of peripheral openings per square meter of the area of the peripheral region is 2 to 50, preferably 3 to 44, or 4 to 25. In order to achieve a more uniform introduction of gas, it is preferable that the peripheral region has the same number of peripheral openings per unit cross-sectional area.

[0060] According to one embodiment of the present invention, the number of central openings per unit area of the central region is substantially the same.

[0061] According to one embodiment of the present invention, the arrangement of the central openings is not particularly limited, but as shown in FIGS. 2A and 2B, it is arranged in a substantially square, equilateral triangle, regular rhombus, or concentric circle shape, preferably in a substantially square or equilateral triangle shape.

[0062] According to one embodiment of the present invention, the arrangement of the peripheral openings is not particularly limited, but as shown in FIGS. 2A and 2B, it is arranged in a substantially square, equilateral triangle, regular rhombus, or concentric circle shape, preferably in a substantially square or equilateral triangle shape.

[0063] Taking an acrylonitrile fluidized bed reactor as an example and referring to the square arrangement shown in FIG. 2A, the inventors of the present application found the following. When the distance between the openings is too large compared to the diameter of the bubbles, the gas released from the four openings flows upward at the center of the square but is insufficient to fluidize the catalyst. The non-fluidized catalyst causes the ammoxidation reaction of the feed gas on the catalyst surface like a small fixed bed, and finally loses its activity due to over-reduction. The catalyst at the center of the square is not involved in the ammoxidation reaction of propylene. This reduces the utilization rate of the catalyst, increases the catalyst load of the reactor, and ultimately has an adverse effect on the reaction results. On the other hand, the distance between the openings should not be made too small. When the distance between the openings is smaller than the diameter of the bubbles, coalescence of the bubbles generated above adjacent openings can easily occur. And since the volume of the coalesced bubbles is larger than the sum of the volumes of the two bubbles before coalescence, more reaction gas can short-circuit through the bubbles and pass through the layer. As a result, the opportunity for contact between the gas and the catalyst particles decreases, the mass transfer efficiency decreases, and ultimately the reaction performance also decreases. Therefore, in order to provide a good initial fluidization state in the fluidized bed, it is desirable that the openings have an appropriate distance. The distance between the openings is preferably slightly larger than the diameter of the initial bubbles generated on the gas distribution plate.

[0064] According to one embodiment of the present invention, the inventors of the present application have found through theoretical calculations and experimental verifications on initial bubbles that the distance between any two adjacent central openings (i.e., the interval between the openings) is the same or different from each other, preferably the same as each other, and is respectively 100 to 300 mm, preferably 125 to 285 mm, more preferably 150 to 270 mm. Here, the interval between the openings is defined as the side length of the pattern of the arrangement of the openings.

[0065] According to one embodiment of the present invention, the inventors of the present application have found through theoretical calculations and experimental verifications on initial bubbles that the distance between any two adjacent peripheral openings (i.e., the interval between the openings) is the same or different from each other, preferably the same as each other, and is respectively 100 to 300 mm, preferably 125 to 285 mm, more preferably 150 to 270 mm. Here, the interval between the openings is defined as the side length of the pattern of the arrangement of the openings.

[0066] According to one embodiment of the present invention, the metal plate is substantially circular, and the diameter of the circle is typically 5 to 29 m, preferably 7 to 20 m.

[0067] According to one embodiment of the present invention, the thickness of the metal plate is typically 5 to 40 mm, preferably 10 to 35 mm.

[0068] According to one embodiment of the present invention, at least one, preferably all, of the central openings have a nozzle (referred to as a central nozzle). Further, at least one (preferably all) of the peripheral openings have a nozzle (referred to as a peripheral nozzle).

[0069] According to an embodiment of the present invention, the central nozzle is a hollow tube. The starting end of the central nozzle is inserted into the central opening, is perpendicularly connected to the metal plate, and is coaxial with the central opening. Preferably, the ending end of the central nozzle has a hole (orifice) (referred to as a central hole (central orifice)). Further, the peripheral nozzle is a hollow tube. The starting end of the peripheral nozzle is inserted into the peripheral opening, is perpendicularly connected to the metal plate, and is coaxial with the peripheral opening. Preferably, the ending end of the peripheral nozzle has a hole (orifice) (referred to as a peripheral hole (peripheral orifice)).

[0070] The inventors of the present invention have found the following. In order to avoid erosion of solid particles such as catalysts by a gas with a high flow rate, the gas introduced from the air inlet 8 into the interior of a fluidized device such as a fluidized bed reactor usually cannot directly pass through the opening of the gas distribution plate. However, instead, as shown in FIG. 3, nozzles 3 are provided on the metal plate of the air distribution plate 6. The plurality of nozzles 3 are arranged on the lower surface of the metal plate and correspond one by one to the openings of the metal plate. The upper end of the nozzle 3 is connected to the opening of the metal plate. The central part as the nozzle body is a cylindrical hollow metal tube. And a hole 2 is provided at the lower end of the nozzle. The nozzle is perpendicular to the metal plate, and the nozzle body, the hole, and the opening are coaxial. That is, a short pipe (i.e., the nozzle) is used for the connection between the opening and the hole, and the opening, the hole, and the nozzle are coaxial. Also, so as to obtain a rectifying effect, the inner diameter D of the nozzle 3 is set to be larger than the diameter d of the hole 2, and at the other end, the diameter of the opening is set to be the same as the outer diameter of the nozzle 3. Regarding the inner diameter D of the nozzle 3, the speed of the gas in the nozzle body is typically set in the range of 8 to 50 m / s, preferably 12 to 40 m / s.

[0071] According to an embodiment of the present invention, the connection between the nozzle and the metal plate is not particularly limited, and conventional connections such as welding or screw connection can be used.

[0072] According to an embodiment of the present invention, the opening diameters d of the respective central holes are the same as or different from each other, preferably the same as each other, and are each 5 to 20 mm, preferably 7 to 18 mm, more preferably 10 to 16 mm.

[0073] According to an embodiment of the present invention, the opening diameters d' of the respective peripheral holes are the same as or different from each other, preferably the same as each other, and are each 5 to 20 mm, preferably 7 to 18 mm, more preferably 10 to 16 mm.

[0074] According to an embodiment of the present invention, the opening diameter d of the central hole is the same as or different from the opening diameter d' of the peripheral hole. Preferably, the relationship 1.10 ≥ d / d' ≥ 1.00, preferably 1.04 ≥ d / d' ≥ 1.00 is satisfied.

[0075] The inventors of the present application have found the following through hydrodynamic research. When the diameter changes in the process of the gas passing through the hole and reaching the nozzle, the flow velocity and direction of the fluid change. Therefore, near the position where the diameter changes, there may be a backflow of a part of the fluid. The backflow may cause a change in the fluid state, such as a change from laminar flow motion to turbulent flow motion at the said position, and the fluid in the turbulent flow region has a disorderly and unstable motion state. The turbulent flow region gradually approaches the pipe wall along the flow direction of the fluid until the turbulent flow region is eliminated. As a result, the motion state of the fluid becomes a gradually stable laminar flow motion along the flow direction. When viewed from the perspective of the flow field of the fluid, in the region from the position where the diameter changes to the position where the turbulent flow region is eliminated, there is a boundary line between the turbulent flow layer and the laminar flow layer. As shown in FIG. 4, the length of the nozzle 3 from the diameter change position to the upper surface of the gas distribution plate is defined as the nozzle length L, and the length of the nozzle 3 from the diameter change position to the position where the turbulent flow region is eliminated is defined as the minimum nozzle length l.

[0076] In this case, the injection angle α can be expressed by the following formula (1): α = 2acrtg(D / 2L) (1) Also, the injection angle β can be expressed by the following formula (2): β = 2 arctan(D / 2l) (2) Here, D represents the inner diameter of the nozzle expressed in mm, L represents the nozzle length expressed in mm, and l represents the minimum nozzle length expressed in mm.

[0077] According to the present invention, as can be seen from the above formulas (1) and / or (2), the smaller the injection angles α and / or β, that is, the smaller the ratio of the inner diameter D of the nozzle to the nozzle length L and / or l, the longer the nozzle length L and / or L are required to be with respect to the fixed inner diameter D of the nozzle. On the other hand, only when the nozzle length L is equal to or greater than the minimum nozzle length l, it is possible to realize a state in which the irregular gas flow generated by the change in diameter becomes a stable linear air flow. As a result, the gas can have a stable flow velocity and a stable air flow direction while passing through the opening.

[0078] According to an embodiment of the present invention, the injection angle α of the central nozzle is 2° to 20°, preferably 4° to 17°, more preferably 5° to 14°. Also, the injection angle α of the peripheral nozzle is 2° to 20°, preferably 4° to 17°, more preferably 5° to 14°.

[0079] According to an embodiment of the present invention, the length of the central nozzle is 80 to 300 mm, preferably 100 to 270 mm, more preferably 120 to 240 mm.

[0080] According to an embodiment of the present invention, the length of the peripheral nozzle is 80 to 300 mm, preferably 100 to 270 mm, more preferably 120 to 240 mm.

[0081] The inventors of the present application have found through a large number of calculations and experiments that in the most preferable state, an optimal rectifying effect can be obtained with an injection angle α of 5° to 14° and a nozzle length of 120 to 240 mm.

[0082] According to one embodiment of the present invention, the opening diameter D1 of the central opening is the same as or different from the opening diameter D1' of the peripheral opening. Preferably, the opening diameter D1 is larger than the opening diameter D1'. In particular, if 1.10 ≧ D1 / D1' > 1.00, the deterioration of fluidity due to the wall effect can be effectively improved. More preferably, the ratio D1 / D1' is set to satisfy 1.08 ≧ D1 / D1' > 1.00, and even more preferably, the ratio D1 / D1' is set to satisfy 1.06 ≧ D1 / D1' > 1.01. When D1 / D1' is larger than 1.10, the flow rectifying effect of the nozzle can be reduced.

[0083] According to one embodiment of the present invention, assuming that the opening diameter of the central hole is d (unit: mm), the opening diameter of the peripheral hole is d' (unit: mm), the opening diameter of the central opening is D1 (unit: mm), and the opening diameter of the peripheral opening is D1' (unit: mm), then (d' / D1') / (d / D1) ≧ 1, preferably (d' / D1') / (d / D1) = 1 to 1.25, (d' / D1') / (d / D1) = 1 to 1.20, or (d' / D1') / (d / D1) = 1.01 to 1.10.

[0084] According to one embodiment of the present invention, the inner diameters D2 of each of the central nozzles are the same as or different from each other, preferably the same as each other, and are respectively 6 to 50 mm, preferably 10 to 47 mm, and more preferably 12 to 44 mm.

[0085] According to one embodiment of the present invention, the inner diameters D2' of each of the peripheral nozzles are the same as or different from each other, preferably the same as each other, and are respectively 5 to 48 mm, preferably 9 to 45 mm, and more preferably 11 to 42 mm.

[0086] According to one embodiment of the present invention, the inner diameter D2 of the central nozzle is the same as or different from the inner diameter D2' of the peripheral nozzle. Preferably, the inner diameter D2 is larger than the inner diameter D2', and more preferably, D2 / D2' satisfies the relationship of 1.10 ≧ D2 / D2' > 1.00, preferably 1.08 ≧ D2 / D2' > 1.00, and more preferably 1.06 ≧ D2 / D2' > 1.01.

[0087] According to an embodiment of the present invention, it relates to a fluidization device, particularly a fluidized bed reactor, more specifically an ammonia oxidation fluidized bed reactor. The fluidization device includes at least a housing, a fluidization device chamber defined by the housing, and a gas distribution plate disposed in the fluidization device chamber. Here, the gas distribution plate is the gas distribution plate in any of the foregoing aspects of the present invention.

[0088] According to an embodiment of the present invention, the method of fixing the gas distribution plate to the fluidization device is not particularly limited, and any connection method conventionally used by those skilled in the art can be adopted.

[0089] According to an embodiment of the present invention, the internal chamber of the fluidization device has a layer (bed) of solid particles, particularly catalyst particles, more specifically ammonia oxidation catalyst particles. Here, the ammonia oxidation catalyst may be any conventionally known ammonia oxidation catalyst and is not particularly limited.

[0090] According to an embodiment of the present invention, the present invention also relates to an oxidation or ammoxidation method including a step of oxidizing or ammoxidizing a feedstock with an oxidation gas to produce an oxide or an ammoxide. Here, specific examples of the feedstock include waste and hydrocarbon feedstocks, particularly C 2~8 olefins or propylene. As the oxidation gas, in particular, air or oxygen can be mentioned. As the oxide or ammoxide, in particular, propylene oxide or acrylonitrile can be mentioned. In addition, the reaction step is carried out using the gas distribution plate according to any of the foregoing aspects of the present invention as the gas distribution plate for the oxidation gas or in a fluidized bed reactor according to any of the foregoing aspects of the present invention.

[0091] The inventors of the present invention have found the following. While the fluidization device is operating, particularly when the reactor is used for the oxidation of propylene and ammonia as an acrylonitrile fluidized bed reactor, the pressure loss ΔP of the gas distribution plate dis an important parameter. A good design of the pressure loss of the gas distribution plate can ensure that the same gas flow rate is supplied to each nozzle of the gas distribution plate, that is, the gas flow rate per unit cross-section of the device is the same. During the process of passing the gas through the holes, local pressure loss occurs. This is the pressure difference between the position indicated by reference numeral 5 and the position indicated by reference numeral 9 in FIG. 5, and the said pressure difference is the pressure loss ΔP of the gas distribution plate d is. The greater the pressure loss ΔP d of the distribution plate in the fluidized bed device, the more uniform the gas distribution becomes.

[0092] The inventors of the present invention have also found the following. There is a correlation between the pressure loss ΔP d of the gas distribution plate, the interval between the openings, the velocity of the gas passing through the openings, and the opening diameter of the holes. In a fluidized bed device such as an acrylonitrile fluidized bed reactor of the same size, when the interval between the openings is the same, the greater the pressure loss ΔP d of the gas distribution plate, the higher the velocity of the gas passing through the openings and the smaller the required hole diameter. However, the hole diameter cannot be set too small. Otherwise, on the one hand, due to the high velocity of the gas passing through the openings, the wear of the holes may deteriorate, and on the other hand, the holes may be easily blocked by foreign matters. Similarly, when the hole diameters are the same, in a device having a higher pressure loss ΔP d of the gas distribution plate, the velocity of the gas passing through the openings is higher and a larger interval between the openings is required. Here too, the interval between the openings cannot be made very large or very small, but should be correlated with the size of the bubbles generated at a position slightly above the distribution plate.

[0093] The inventors of the present invention have further found the following. The current pressure loss ΔP dis typically designed to be 60% of the pressure loss of the bed. However, as the production scale continuously expands, the diameter of fluidized devices such as acrylonitrile fluidized bed reactors also increases. For example, for an acrylonitrile fluidized bed reactor with a diameter larger than 8.5 meters, when the design parameter of the pressure loss of the bed is 60%, a larger pore diameter or a smaller interval between openings will be required compared to the case where the design parameter of the pressure loss of the bed is larger than 60%. If the pore diameter is large, the catalyst is likely to fall into the conical part of the reactor that is not utilized, which is not desirable. Alternatively, if the interval between the openings is small, the number of openings increases, the number of air nozzles increases, and the number of branch pipes and nozzles of the propylene - ammonia distributor corresponding to each air nozzle increases, leading to an increase in the cost of the device. According to the present invention, when comprehensively considering the elements of the pore diameter, the interval between the openings, and the velocity of the gas passing through the openings, the pressure loss ΔP of the gas distribution plate d is 62 - 120% of the pressure loss ΔP of the bed b , preferably 65 - 115% of the pressure loss ΔP of the bed b , more preferably 68 - 110% of the pressure loss ΔP of the bed b d . As a result, the object of providing a uniform gas flow rate per unit cross - section of the device can be better achieved.

[0094] According to a preferred embodiment of the present invention, the gas passing through the gas distribution plate is placed in a state of the same temperature, pressure, etc. in a fluidized device such as an acrylonitrile fluidized bed reactor. To control the pressure loss ΔP of the gas distribution plate d within a preferred range, the parameters corresponding to the pressure loss ΔP of the gas distribution plate described above d are typically selected as follows. P d is designed to be 62 - 120% of the pressure loss ΔP of the bed b , the pore diameter at the lower end of the nozzle of the gas distribution plate is 5 - 20 mm, and the interval between the openings of the gas distribution plate is 100 - 300 mm. Preferably, P d is the pressure loss ΔP of the bed bIt is designed to be 65 to 115% of , the pore diameter is 7 to 18 mm, and the distance between the openings is 125 to 285 mm. More preferably, P d is the pressure loss ΔP of the layer b is designed to be 68 to 110% of , the pore diameter is 10 to 16 mm, and the distance between the openings is 150 to 270 mm. On the other hand, when P d is within the above range, wear of the holes caused by the high-speed gas passing through the openings can be avoided.

[0095] According to one embodiment of the present invention, the ammoxidation treatment can be carried out by any method and any technique conventionally known in the art. Such information is known to those skilled in the art, and a detailed description thereof is omitted here. However, regardless of the above, specific examples of the conditions for the reaction process include the following. The molar ratio of propylene to ammonia to air (calculated based on oxygen molecules) is typically 1:1.1 to 1.3:1.8 to 2.0, the reaction temperature is typically 420 to 440 ° C, the reaction pressure (gauge pressure) is typically 0.03 to 0.14 MPa, and the weight hourly space velocity is typically 0.04 to 0.10 h -1 -1.

[0096] [Examples] Hereinafter, the present application will be described in more detail using examples and comparative examples. However, the present application is not limited to the following examples.

[0097] In the following examples and comparative examples, the single-pass yield of acrylonitrile and the propylene conversion rate can be calculated according to the following formulas: Single-pass yield of acrylonitrile: AN% = C AN / ΣC × 100 Propylene conversion rate: Cc 3 % = (1 - Cc 3out / Cc 3in ) × 100 Here, C AN is the molar amount (mol) of carbon contained in AN in the gas at the outlet of the reactor, ΣC is the total molar amount (mol) of carbon in the gas at the outlet of the reactor, and Cc3out is the molar amount (mol) of carbon contained in C in the gas at the reactor outlet, and Cc 3 is the molar amount (mol) of carbon contained in C in the gas at the reactor inlet. 3in is the molar amount (mol) of carbon contained in C in the gas at the reactor inlet. 3 is the molar amount (mol) of carbon contained in C in the gas at the reactor inlet.

[0098] 〔Comparative Example 1〕 As shown in FIG. 5, the fluidized bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0099] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0100] The number of central openings was 29 per square meter in the central region. The central openings each had an opening diameter D1 of 42 mm, and were evenly arranged in a square shape with a 197 mm interval between the openings. The central holes each had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0101] The number of peripheral openings was 20.5 per square meter in the peripheral region. The peripheral openings each had an opening diameter D1' of 36 mm, and the interval between adjacent peripheral openings was 197 mm. The opening diameter d' of the peripheral holes was 14.3 mm each, and the inner diameter D2' was 30 mm.

[0102] D1 / D1' was 1.17, d / d' was 1, and (d' / D1') / (d / D1) was 1.17.

[0103] The gas phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0104] 〔Comparative Example 2〕 As shown in FIG. 5, the fluidized bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, the reaction temperature is 430 °C, the reaction pressure is 0.04 MPa, and the propylene:ammonia:air ratio is 1:1.2:9.6.

[0105] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0106] The number of central openings was 29 per square meter of the central region. Each central opening had an opening diameter D1 of 42 mm, and the openings were evenly arranged in a square shape with a 197 mm interval between them. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0107] The number of peripheral openings was 20.5 per square meter of the peripheral region. Each peripheral opening had an opening diameter D1' of 42 mm, and the interval between adjacent peripheral openings was 197 mm. The opening diameter d' of each peripheral hole was 14.3 mm, and the inner diameter D2' was 36 mm.

[0108] D1 / D1' was 1.00, D / D' was 1, and (d' / D1') / (d / D1) was 1.00.

[0109] The gas phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0110] [Example 1] As shown in Fig. 5, the fluidized bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, the reaction temperature was 430 °C, the reaction pressure was 0.04 MPa, and the propylene:ammonia:air ratio was 1:1.2:9.6.

[0111] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0112] The number of central openings was 29 per square meter of the central region. Each central opening had an opening diameter D1 of 42 mm, and the openings were evenly arranged in a square shape with a 197-mm gap between them. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm. The velocity of the gas passing through the central openings was 10.6 m / s.

[0113] The number of peripheral openings was 20.5 per square meter of the peripheral region. Each peripheral opening had an opening diameter D1' of 40 mm, and the gap between adjacent peripheral openings was 197 mm. The opening diameter d' of each peripheral hole was 14.3 mm, and the inner diameter D2' was 34 mm. The velocity of the gas passing through the peripheral openings was 11.8 m / s.

[0114] D1 / D1' was 1.05, d / d' was 1, and (d' / D1') / (d / D1) was 1.05.

[0115] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0116] 〔Example 2〕 As shown in Fig. 5, the fluidized-bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0117] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a central region radius r of 7.92 m.

[0118] The number of central openings was 29 per square meter of the central region. Each central opening had an opening diameter D1 of 42 mm, and the openings were evenly arranged in a square shape with a 197-mm gap between them. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0119] The number of peripheral openings was 20.5 per square meter in the peripheral area. Each peripheral opening had an opening diameter D1’ of 39 mm, the distance between adjacent peripheral openings was 197 mm, the opening diameter d’ of the peripheral holes was 14.3 mm each, and the inner diameter D2’ was 35 mm.

[0120] D1 / D1’ was 1.08, d / d’ was 1, and (d’ / D1’) / (d / D1) was 1.08.

[0121] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0122] [Example 3] As shown in Fig. 5, the fluidized bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0123] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a central region radius r of 7.92 m.

[0124] The number of central openings was 13 per square meter in the central region. Each central opening had an opening diameter D1 of 51 mm, and they were evenly arranged in a square shape with a 275 mm interval between the openings. The central holes each had an opening diameter d of 15.1 mm and an inner diameter D2 of 45 mm.

[0125] The number of peripheral openings was 9 per square meter in the peripheral area. Each peripheral opening had an opening diameter D1’ of 48 mm, the distance between adjacent peripheral openings was 275 mm, the opening diameter d’ of the peripheral holes was 15.1 mm each, and the inner diameter D2’ was 42 mm.

[0126] D1 / D1’ was 1.06, d / d’ was 1, and (d’ / D1’) / (d / D1) was 1.06.

[0127] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0128] [Example 4] As shown in Fig. 5, the fluidized bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0129] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0130] The number of central openings was 118 per square meter in the central region. The central openings each had an opening diameter D1 of 25 mm, and were evenly arranged in a triangular shape with a 95 mm interval between the openings. The central holes each had an opening diameter D of 9.6 mm and an inner diameter D2 of 20 mm.

[0131] The number of peripheral openings was 84 per square meter in the peripheral region. The peripheral openings each had an opening diameter D1' of 24 mm, and the interval between adjacent peripheral openings was 95 mm. The opening diameter d' of the peripheral holes was 9.6 mm each, and the inner diameter D2' was 19 mm.

[0132] D1 / D1' was 1.04, d / d' was 1, and (d' / D1') / (d / D1) was 1.04.

[0133] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0134] [Example 5] As shown in Fig. 5, the fluidized bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0135] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0136] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm and was evenly arranged in a square shape with a 197 - mm interval between the openings. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0137] The number of peripheral openings was 20.5 per square meter in the peripheral region. Each peripheral opening had an opening diameter D1’ of 40 mm, the interval between adjacent peripheral openings was 197 mm, the opening diameter d’ of each peripheral hole was 14.1 mm, and the inner diameter D2’ was 34 mm.

[0138] D1 / D1’ was 1.05, d / d’ was 1.01, and (d’ / D1’) / (d / D1) was 1.04.

[0139] The gas - phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0140] 〔Example 6〕 As shown in Fig. 5, the fluidized - bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0141] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0142] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm and was evenly arranged in a square shape with a 197 - mm interval between the openings. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0143] The number of peripheral openings was 20.5 per square meter of the peripheral region. Each peripheral opening had an opening diameter D1’ of 39 mm, the distance between adjacent peripheral openings was 197 mm, the opening diameter d’ of the peripheral holes was 12.7 mm each, and the inner diameter D2’ was 33 mm.

[0144] D1 / D1’ was 1.08, d / d’ was 1.13, and (d’ / D1’) / (d / D1) was 0.96.

[0145] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0146] [Example 7] As shown in Fig. 5, the fluidized bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0147] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a central region radius r of 7.92 m.

[0148] The number of central openings was 29 per square meter of the central region. Each central opening had an opening diameter D1 of 42 mm, and they were evenly arranged in a square shape with a 197 mm interval between the openings. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0149] The number of peripheral openings was 20.5 per square meter of the peripheral region. Each peripheral opening had an opening diameter D1’ of 40 mm, the distance between adjacent peripheral openings was 197 mm, the opening diameter d’ of the peripheral holes was 15.2 mm each, and the inner diameter D2’ was 34 mm.

[0150] D1 / D1’ was 1.05, d / D’ was 0.94, and (d’ / D1’) / (d / D1) was 1.12.

[0151] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0152] Example 8 As shown in Figure 5, the fluidized-bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0153] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0154] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm, and the openings were evenly arranged in a square shape with a 197-mm interval between them. Each central hole had an opening diameter d of 14.3 mm, an inner diameter D2 of 36 mm, and a nozzle injection angle α of 12°.

[0155] The number of peripheral openings was 20.5 per square meter in the peripheral region. Each peripheral opening had an opening diameter D1' of 40 mm, and the interval between adjacent peripheral openings was 197 mm. The opening diameter d' of each peripheral hole was 14.3 mm, the inner diameter D2' was 34 mm, and the nozzle injection angle α was 12°.

[0156] D1 / D1' was 1.05, d / d' was 1, and (d' / D1') / (d / D1) was 1.05.

[0157] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0158] Example 9 As shown in Figure 5, the fluidized-bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0159] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0160] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm, and the openings were evenly arranged in a square shape with a 197 - mm interval between them. Each central hole had an opening diameter d of 14.3 mm, an inner diameter D2 of 36 mm, and a nozzle injection angle α of 3°.

[0161] The number of peripheral openings was 20.5 per square meter in the peripheral region. Each peripheral opening had an opening diameter D1’ of 40 mm, and the interval between adjacent peripheral openings was 197 mm. The opening diameter d’ of each peripheral hole was 14.3 mm, the inner diameter D2’ was 34 mm, and the nozzle injection angle α was 3°.

[0162] D1 / D1’ was 1.05, d / d’ was 1, and (d’ / D1’) / (d / D1) was 1.05.

[0163] The gas - phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0164] Since the injection angle was small, the nozzle length was 687 mm. Although the installation of the device was possible, it was not inexpensive.

[0165] 〔Example 10〕 As shown in Figure 5, the fluidized - bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0166] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0167] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm and was evenly arranged in a square shape with a 197-mm gap between adjacent openings. Each central hole had an opening diameter d of 14.3 mm, an inner diameter D2 of 36 mm, and a nozzle injection angle α of 25°.

[0168] The number of peripheral openings was 20.5 per square meter in the peripheral region. Each peripheral opening had an opening diameter D1' of 40 mm, and the gap between adjacent peripheral openings was 197 mm. The opening diameter d' of each peripheral hole was 14.3 mm, the inner diameter D2' was 34 mm, and the nozzle injection angle α was 25°.

[0169] D1 / D1' was 1.05, d / d' was 1, and (d' / D1') / (d / D1) was 1.05.

[0170] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0171] 〔Example 11〕 As shown in Fig. 5, the fluidized-bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0172] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a central region radius r of 7.92 m.

[0173] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm and was evenly arranged in a square shape with a 197-mm gap between adjacent openings. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0174] The number of peripheral openings was 20.5 per square meter of the peripheral area. Each peripheral opening had an opening diameter D1’ of 41 mm, the interval between adjacent peripheral openings was 197 mm, the opening diameter d’ of the peripheral holes was 12.7 mm each, and the inner diameter D2’ was 35 mm.

[0175] D1 / D1’ was 1.02, d / d’ was 1.13, and (d’ / D1’) / (d / D1) was 0.91.

[0176] The gas phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0177] 〔Example 12〕 As shown in Fig. 5, the fluidized bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0178] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a central region radius r of 7.92 m.

[0179] The number of central openings was 29 per square meter of the central region. Each central opening had an opening diameter D1 of 42 mm, and was evenly arranged in a square shape with a 197 mm interval between the openings. Each central hole had an opening diameter d of 14.3 mm and an inner diameter D2 of 36 mm.

[0180] The number of peripheral openings was 20.5 per square meter of the peripheral area. Each peripheral opening had an opening diameter D1’ of 40 mm, the interval between adjacent peripheral openings was 197 mm, the opening diameter d’ of the peripheral holes was 14.3 mm each, and the inner diameter D2’ was 34 mm.

[0181] The pressure loss ΔP of the air distribution plate d was measured at the total capacity of the apparatus and was 88% of the pressure loss ΔP of the layer. b of the layer.

[0182] D1 / D1’ was 1.05, d / d’ was 1, and (d’ / D1’) / (d / D1) was 1.05.

[0183] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0184] [Example 13] As shown in Fig. 5, the fluidized-bed reactor had a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0185] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0186] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm, and the openings were evenly arranged in a square shape with a 197-mm interval between them. Each central hole had an opening diameter d of 14.9 mm and an inner diameter D2 of 36 mm.

[0187] The number of peripheral openings was 20.5 per square meter in the peripheral region. Each peripheral opening had an opening diameter D1’ of 40 mm, and the interval between adjacent peripheral openings was 197 mm. The opening diameter d’ of each peripheral hole was 14.9 mm, and the inner diameter D2’ was 34 mm.

[0188] The pressure loss ΔP of the air distribution plate d was measured at the total capacity of the apparatus and was 55% of the pressure loss ΔP b of the bed.

[0189] D1 / D1’ was 1.05, d / d’ was 1, and (d’ / D1’) / (d / D1) was 1.05.

[0190] The gas-phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0191] 〔Example 14〕 As shown in Fig. 5, the fluidized bed reactor has a diameter of 9.0 m, a propylene supply rate of 9500 NM 3 / h, a reaction temperature of 430 °C, a reaction pressure of 0.04 MPa, and a propylene:ammonia:air ratio of 1:1.2:9.6.

[0192] The air distribution plate 6 was a circular metal plate with a diameter of 9.0 m, a thickness of 16 mm, and a radius r of the central region of 7.92 m.

[0193] The number of central openings was 29 per square meter in the central region. Each central opening had an opening diameter D1 of 42 mm and was evenly arranged in a square shape with a 197 mm interval between the openings. Each central hole had an opening diameter d of 14.6 mm and an inner diameter D2 of 36 mm.

[0194] The number of peripheral openings was 20.5 per square meter in the peripheral region. Each peripheral opening had an opening diameter D1’ of 40 mm, and the interval between adjacent peripheral openings was 197 mm. The opening diameter d’ of each peripheral hole was 14.6 mm, and the inner diameter D2’ was 34 mm.

[0195] The pressure loss ΔP of the air distribution plate d was measured at the total capacity of the apparatus and was 130% of the pressure loss ΔP b of the layer.

[0196] D1 / D1’ was 1.05, d / d’ was 1, and (d’ / D1’) / (d / D1) was 1.05.

[0197] The gas phase compositions in the central region, wall region, and outlet of the reactor were measured separately, and the results are shown in Table 1.

[0198]

Table 1

[0199] As can be seen from Table 1, by using the gas distribution plate of the present invention, the fluidity of the catalyst near the reactor wall surface can be improved, and the propylene conversion rate and the acrylonitrile yield can be significantly increased.

Brief Description of the Drawings

[0200]

Figure 1

Figure 2A

Figure 2B

Figure 3

Figure 4

Figure 5

Claims

1. A metal plate, a plurality of openings called central openings provided in a central region of the metal plate, and a plurality of openings called peripheral openings provided in a peripheral region of the metal plate, wherein a ratio D1 / D1' of an opening diameter D1 (unit: mm) of the central opening to an opening diameter D1' (unit: mm) of the peripheral opening satisfies a relationship of 1.10 ≥ D1 / D1' ≥ 1.01, a straight-line distance between an arbitrary point on an outer periphery of the metal plate and a center point of the metal plate is denoted as R, a region surrounded by all points on the metal plate at a straight-line distance r from the center point is defined as the central region, a region between the central region and the outer periphery is defined as the peripheral region, and a value of r / R is 0.5 to 0.85, at least one of the central openings has a nozzle called a central nozzle, the central nozzle is a hollow tube with a start end of the central nozzle inserted into the central opening, is perpendicularly connected to the metal plate, is coaxial with the central opening, and a terminal end of the central nozzle has a hole called a central hole, and / or at least one of the peripheral openings has a nozzle called a peripheral nozzle, the peripheral nozzle is a hollow tube with a start end of the peripheral nozzle inserted into the peripheral opening, is perpendicularly connected to the metal plate, is coaxial with the peripheral opening, and a terminal end of the peripheral nozzle has a hole called a peripheral hole, when an opening diameter of the central hole is denoted as d (unit: mm) and an opening diameter of the peripheral hole is denoted as d' (unit: mm), the opening diameter d of the central hole is the same as or different from the opening diameter d' of the peripheral hole, and (d' / D1') / (d / D1) satisfies a relationship of (d' / D1') / (d / D1) ≥ 1, and at the same time, d / d' satisfies a relationship of 1.10 ≥ d / d' ≥ 1.00, a gas distribution plate.

2. An air distribution plate for an ammoxidation fluidized bed reactor, and / or the metal plate is flat, and / or the ratio D1 / D1' satisfies a relationship of 1.06 ≥ D1 / D1' ≥ 1.01, the gas distribution plate according to Claim 1.

3. each of the opening diameters D1 of the central openings is the same as or different from each other and is 16 to 60 mm, and / or each of the opening diameters D1' of the peripheral openings is the same as or different from each other and is 15 to 58 mm, the gas distribution plate according to Claim 1. **Claim 4**: The opening diameters D1 of each of the central openings are the same as or different from each other, each being 22 to 52 mm, and / or the opening diameters D1' of each of the peripheral openings are the same as or different from each other, each being 21 to 50 mm. The gas distribution plate according to claim 3. **Claim 5** The number of the central openings is 16 to 100 per square meter of the central region, and / or the number of the peripheral openings is 2 to 50 per square meter of the peripheral region, and / or the number of the central openings is 70% to 99% of the total number of the openings of the metal plate. The gas distribution plate according to claim 1. **Claim 6**: The number of the central openings is 18 to 44 per square meter of the central region, and / or the number of the peripheral openings is 4 to 25 per square meter of the peripheral region, and / or the number of the central openings is 80% to 95% of the total number of the openings of the metal plate. The gas distribution plate according to claim 5. **Claim 7** The number of the central openings per unit area of the central region is the same. The gas distribution plate according to claim 1. **Claim 8** The central openings and / or the peripheral openings are arranged in a square lattice, a triangular lattice, a rhombic lattice, or a concentric circle pattern. The gas distribution plate according to claim 1. **Claim 9**: The central openings and / or the peripheral openings are arranged in a square lattice or a triangular lattice. The gas distribution plate according to claim 8. **Claim 10** The distances between any two adjacent central openings are the same as or different from each other, each being 100 to 300 mm, and / or the distances between any two adjacent peripheral openings are the same as or different from each other, each being 100 to 300 mm. The gas distribution plate according to claim 1. **Claim 11**: The distances between any two adjacent central openings are the same as or different from each other, each being 150 to 270 mm, and / or the distances between any two adjacent peripheral openings are the same as or different from each other, each being 150 to 270 mm. The gas distribution plate according to claim 10. **Claim 12** The metal plate is circular, the diameter of the circle is 5 to 29 m, and the thickness is 5 to 40 mm. The gas distribution plate according to claim 1. **Claim 13**: The diameter of the circle of the metal plate is 7 to 20 m, and the thickness of the metal plate is 10 to 35 mm. The gas distribution plate according to claim 12.

14. All of the central openings have the central nozzles, and / or, All of the peripheral openings have the peripheral nozzles, the gas distribution plate according to Claim 1.

15. The opening diameters d of each of the central holes are the same as or different from each other, each being 5 to 20 mm, and, The opening diameters d' of each of the peripheral holes are the same as or different from each other, each being 5 to 20 mm, and / or, The opening diameter d of the central holes is the same as or different from the opening diameter d' of the peripheral holes, and / or, the gas distribution plate according to Claim 1, wherein the relationship 1.04 ≥ d / d' ≥ 1.00 is satisfied.

16. The opening diameters d of each of the central holes are the same as or different from each other, each being 10 to 16 mm, and / or, The opening diameters d' of each of the peripheral holes are the same as or different from each other, each being 10 to 16 mm, the gas distribution plate according to Claim 15.

17. The central nozzle and / or the peripheral nozzle has an injection angle α of 2° to 20°, the gas distribution plate according to Claim 15.

18. The length of the central nozzle and / or the peripheral nozzle is 80 to 300 mm, the gas distribution plate according to Claim 15.

19. (d' / D1') / (d / D1) = 1 to 1.25, the gas distribution plate according to Claim 13.

20. (d' / D1') / (d / D1) = 1.01 to 1.10, the gas distribution plate according to Claim 19.

21. The inner diameters D2 of each of the central nozzles are the same as or different from each other, each being 6 to 50 mm, and / or, The inner diameters D2' of each of the peripheral nozzles are the same as or different from each other, each being 5 to 48 mm, the gas distribution plate according to Claim 13.

22. The inner diameters D2 of each of the central nozzles are the same as or different from each other, each being 12 to 44 mm, and / or, The inner diameters D2' of each of the peripheral nozzles are the same as or different from each other, each being 11 to 42 mm, the gas distribution plate according to Claim 21.

23. All of the central openings have the central nozzles, and / or, All of the peripheral openings have the peripheral nozzles, and / or, (d' / D1') / (d / D1) is 1 to 1.25, the gas distribution plate according to Claim 1.

24. A fluidized bed reactor comprising at least one housing, a fluidization device chamber defined by the housing, and a gas distribution plate disposed within the fluidization device chamber, wherein the gas distribution plate is the gas distribution plate according to claim 1.

25. The fluidized bed reactor according to claim 24, wherein the fluidization device chamber has a layer of solid particles, and the pressure loss ΔPd (unit: MPa) of the gas distribution plate is 62 to 120% of the pressure loss ΔPb (unit: MPa) of the layer of solid particles.

26. The fluidized bed reactor according to claim 25, wherein the solid particles are catalyst particles and / or the pressure loss ΔPd is 68 to 110% of the pressure loss ΔPb.

27. Using the gas distribution plate according to claim 1 as the acid gas distribution plate, in order to produce an amino oxide, C ２～８ A method for ammoxidation, comprising the step of subjecting an olefin to an ammoxidation reaction using an acid gas.

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