Nitrile production method with improved ammonia absorption effect

Abstract

A nitrile production method with an improved ammonia absorption effect, comprising a reaction step of carrying out ammoxidation of a hydrocarbon raw material to produce a nitrile-containing reaction product, and a cooling step of introducing the reaction product to an absorption device through a gas inlet and spraying a spray liquid to the reaction product by means of a spraying device in the absorption device to cool the reaction product and form an absorption atmosphere, wherein when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorption atmosphere is 0.004-0.02 m-1. According to the method, the spray liquid is atomized to increase the contact area with ammonia, thereby improving the ammonia absorption effect.

Description

A method for producing nitrile with improved ammonia absorption effect Technical Field

[0001] The present invention relates to the technical field of gas absorption, and more particularly to a method for producing a nitrile with improved ammonia absorption effect. Background Art

[0002] Ammoniation or ammoxidation process generates the process route of nitriles accordingly. In order to convert unstripped gases such as hydrocarbons as much as possible, generally unstripped gas ammonia is excessive, i.e., ammonia and unstripped gas hydrocarbons mol ratio is greater than 1. As in propylene ammoxidation, the ammonia ratio (ammonia and propylene mol ratio) is 1.10-1.35. As in aromatic hydrocarbon ammoxidation, the ammonia ratio (ammonia and aromatic hydrocarbon mol ratio) is 4-8. Therefore, unreacted ammonia must be contained in the reactor outlet tail gas. On the one hand, as in the acrylonitrile production process, acrylonitrile etc. are easily polymerized under alkaline conditions in the reaction gas. Even if a small amount of unreacted ammonia escapes, it is also easy to cause pollution to the environment. Therefore, in ammoniation or ammoxidation process, it is necessary to utilize absorption unit (generally referred to as ammonia absorber or quench tower) to remove the unreacted ammonia in the gas phase with acid or water. This process is very necessary.

[0003] With the advancement of production technology, production loads are constantly increasing. Larger and more scalable plants are the future trend. The higher the plant load, the larger the equipment, including the absorption unit, becomes. It is known that in the absorption unit, circulating liquid (spraying liquid) is dispersed through the spraying device into the absorption unit, where it comes into countercurrent contact with the ammonia-containing gas and absorbs it, thereby removing excess ammonia from the gas phase.

[0004] Patent CN105425849 removes excess ammonia by adjusting the pH of the absorber effluent and adding acid. Patent CN1199940 improves gas-liquid two-phase mass and heat transfer by adding internal components to the bottom of the absorber, essentially addressing the problem of uniform distribution of the ammonia-containing gas phase. However, ammonia breakthrough is still inevitable in the absorber, meaning that a small amount of ammonia still escapes, leading to product loss in subsequent refining and separation units or causing environmental pollution.

[0005] In the ammonia absorption method of the prior art, after the absorption device has been running for a long period of time, the ammonia content in the absorbed tail gas increases significantly compared to the initial stage of operation.

[0006] Summary of the Invention

[0007] Inside the ammonia absorption tower, a spray liquid is pumped to the nozzles. Due to its high pressure, the liquid enters the nozzle cavity through a tangential inlet, acquiring a rotational motion. After passing through a specially designed nozzle, the spray liquid is ejected at high speed, breaking into countless small droplets. Most of the droplets, influenced by gravity and the centrifugal force of the rotational motion, move downward, where they encounter the upward-moving gas. However, a small number of droplets are entrained by the gas and move upward. The tower is equipped with multiple layers of spraying devices, each containing dozens or even hundreds of nozzles evenly distributed across its cross-section. During operation, the airflow weights the spray area within the tower, filling it with countless droplets. These droplets significantly attenuate both visible and infrared signals. Measuring the extinction coefficient of the droplets within the tower using infrared spectroscopy or forward scattering allows for a comprehensive assessment of droplet size, quantity, and distribution. Generally speaking, if the droplets are large and the number of droplets is small, the absorption of light is small, the light transmittance is high, and the extinction coefficient is small, and vice versa.

[0008] The inventors of the present invention have discovered that this problem can be solved by setting the extinction coefficient of the absorbing atmosphere within a specific numerical range. The present invention has been completed based on this discovery.

[0009] Specifically, the present invention relates to the following aspects.

[0010] 1. A method for producing a nitrile, comprising the steps of causing a hydrocarbon feedstock to undergo an ammoxidation reaction to produce a reaction product containing a nitrile (referred to as a reaction step), and introducing the reaction product into an absorption device through a gas inlet and spraying a spray liquid onto the reaction product in the absorption device through a spray device to cool the reaction product and form an absorption atmosphere (referred to as a cooling step), wherein the extinction coefficient of the absorption atmosphere is 0.004-0.02 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 (Preferably 0.006-0.018m -1 ).

[0011] 2. The manufacturing method according to any one of the preceding or following aspects, wherein the average diameter D of the droplets of the absorption atmosphere when measured at a vertical distance of 3000 mm above the gas inlet is 32 is 400-2600 microns (preferably 600-2400 microns), and / or, when measured at a vertical distance of 3000 mm above the gas inlet, the droplet size distribution D of the absorption atmosphere is 10 150-1500 microns, D 50 700-3000 microns, D 90 1400-3600 microns (preferably D 10 250-1400 microns, D50 800-2800 μm, D 90 is 1600-3500 microns).

[0012] 3. The manufacturing method according to any of the preceding or following aspects, wherein the extinction coefficient of the absorbing atmosphere is 0.001-0.004 m / s when measured at a vertical distance of 8500 mm above the gas inlet. -1 (Preferably 0.0015-0.0035m -1 ), and / or, when measured at a vertical distance of 8500 mm above the gas inlet, the average diameter D of the droplets of the absorption atmosphere 32 is 200-1400 microns (preferably 400-1000 microns), and / or, when measured at a vertical distance of 8500 mm above the gas inlet, the droplet size distribution D of the absorption atmosphere is 10 100-1000 microns, D 50 300-1800 μm, D 90 500-2200 microns (preferably D 10 200-600 microns, D 50 400-1400 μm, D 90 is 600-1800 microns).

[0013] 4. The manufacturing method described in any of the preceding or following aspects, wherein the spraying device includes a spray liquid inlet, a first spray pipe fluidically connected to the spray liquid inlet, a plurality of (e.g., 10-26, preferably 12-22) second spray pipes fluidically connected to the first spray pipe and extending perpendicularly to the first spray pipe on both sides thereof, a plurality of (e.g., 4-26, preferably 6-22) third spray pipes fluidically connected to the second spray pipe and extending perpendicularly to the second spray pipe on both sides thereof, and a nozzle located at the end of the third spray pipe and fluidically connected thereto.

[0014] 5. The manufacturing method according to any of the preceding or following aspects, wherein, on two adjacent second spray pipes, the straight-line distance M between the end of any third spray pipe on one second spray pipe and the end of any third spray pipe on the other adjacent second spray pipe is not less than 320 mm (preferably not less than 350 mm), and / or, the nozzles are the same or different, and the spray liquid spray rate is independently 0.5-7.5 t / h (preferably 0.9-6.5 t / h), and / or, the nozzles are the same or different, and the spray liquid spray rate at the nozzle outlet is 0.5-7.5 t / h (preferably 0.9-6.5 t / h). The pressure is independently 0.03-0.85 MPaG (preferably 0.04-0.65 MPaG), and / or the spray liquid input pressure of the spray liquid inlet is controlled at 0.06-1.00 MPaG (preferably 0.12-0.90 MPaG, more preferably 0.18-0.80 MPaG), and / or the difference (absolute value) between the spray liquid input pressures of any two spraying devices at the spray liquid inlets is less than 0.024 MPa (preferably less than 0.018 MPa, more preferably less than 0.012 MPa).

[0015] 6. The manufacturing method described in any of the preceding or following aspects, wherein a plurality (e.g., 2-10, preferably 4-8) of the spraying devices are layered inside the absorption device at predetermined vertical intervals along the central axis of the absorption device, and / or the vertical interval between two adjacent spraying devices (measured by the vertical interval of the spray liquid inlets of the spraying devices) is 650-1350 mm (preferably 750-1200 mm).

[0016] 7. The manufacturing method described in any of the preceding or following aspects, wherein when the absorption device is cut across in a direction perpendicular to the central axis of the absorption device to obtain a cross section, the projections of at least one (preferably all) of the first spray pipe, the second spray pipe and the third spray pipe selected from one of the multiple spray devices and another of the multiple spray devices on the cross section basically coincide.

[0017] 8. The manufacturing method described in any of the preceding or following aspects, wherein the projections of all nozzles of the one spraying device and the other spraying device on the cross section substantially overlap, and / or the two nozzles whose projections substantially overlap have the same spray diameter, and / or the two nozzles whose projections substantially overlap have the same spray liquid rotation direction.

[0018] 9. The manufacturing method described in any of the preceding or following aspects, wherein the vertical distance between the gas inlet and the spray liquid inlet of the spraying device (when there are multiple spraying devices, it refers to the spraying device closest to the gas inlet) is 800-6000 mm (preferably 1000-5000 mm), and / or the inner diameter of the gas inlet is 800-1900 mm (preferably 900-1700 mm), and / or the linear velocity of the reaction product in the absorption device is 0.6-1.5 m / s (preferably 0.7-1.3 m / s), and / or the mass flow rate ratio of the spray liquid to the reaction product is 15-25:1.

[0019] 10. The manufacturing method described in any of the above or following aspects, wherein the internal space of the absorption device between the gas inlet and the spraying device (when there are multiple spraying devices, it refers to the spraying device closest to the gas inlet) does not have any mechanical components that can substantially affect the flow of the gas.

[0020] 11. The manufacturing method according to any one of the preceding or following aspects, wherein the angle between the projections of the spray liquid inlets of the one spray device and the other spray device on the cross section is 180°.

[0021] 12. The absorption device according to any of the preceding or following aspects, wherein among all the spraying devices, the angle between the projections of the spray liquid inlets of any two odd-numbered spraying devices on the cross section is 0°, the angle between the projections of the spray liquid inlets of any two even-numbered spraying devices on the cross section is 0°, and the angle between the projections of the spray liquid inlets of any odd-numbered spraying device and any even-numbered spraying device on the cross section is 180°.

[0022] 13. The absorption device according to any one of the preceding or following aspects, wherein the nozzle comprises a nozzle inlet, a rotation chamber and a nozzle outlet, wherein the rotation chamber is constructed so that the spray liquid entering from the nozzle inlet leaves the nozzle outlet in a rotating manner after passing through the rotation chamber.

[0023] 14. The absorption device according to any one of the preceding or following aspects, wherein on at least one (preferably all) of the second spray pipes, two adjacent (preferably all) nozzles located on the same side of the second spray pipe are constructed so that the spray liquid is sprayed in the same rotation direction.

[0024] 15. The absorption device according to any one of the preceding or following aspects, wherein all nozzles on opposite sides of two adjacent second spray pipes are constructed so that the spray liquid is sprayed in opposite rotation directions.

[0025] 16. The absorption device described in any of the preceding or following aspects, wherein on at least one (preferably all) of the second spray pipes, at least one (preferably all) nozzles located on one side of the second spray pipe are constructed so that the spray liquid is sprayed in a rotation direction A, and at least one (preferably all) nozzles located on the opposite other side of the second spray pipe are constructed so that the spray liquid is sprayed in a rotation direction B, wherein the rotation direction A is opposite to the rotation direction B.

[0026] 17. The absorption device described in any of the preceding or following aspects, wherein among all the nozzles of the spraying device, the number of nozzles spraying the spray liquid in the rotation direction A is equal to or substantially equal to the number of nozzles spraying the spray liquid in the rotation direction B.

[0027] 18. The manufacturing method described in any of the preceding or following aspects, wherein the plurality of second spray pipes extend perpendicularly to the first spray pipe and substantially parallel to its opposite sides along the horizontal direction, and / or the plurality of third spray pipes extend perpendicularly to the second spray pipe and substantially parallel to its opposite sides along the horizontal direction.

[0028] 19. The manufacturing method according to any of the preceding or following aspects, wherein the inner diameter of the first spray pipe is 160-480 mm (preferably 200-450 mm) and the length is 4500-11500 mm (preferably 4800-10500 mm), and / or the multiple second spray pipes are the same or different from each other, and the inner diameters are each independently 30-150 mm (preferably 40-120 mm) and the lengths are each independently 1200-5750 mm (preferably 1800-5250 mm), and / or the multiple third spray pipes are the same or different from each other, and the inner diameters are each independently 10-60 mm (preferably 15-50 mm) and the lengths are each independently 160-325 mm (preferably 175-300 mm).

[0029] 20. The manufacturing method described in any of the preceding or following aspects, wherein the nozzles are the same or different from each other, the inner diameter (referring to the nozzle outlet) is independently 3-20 mm (preferably 6-14 mm), the diameter of the rotating chamber is independently 10.0-55.0 mm (preferably 13.0-45.0 mm), and the spraying angle is independently 65-120° (preferably 70-100°).

[0030] 21. The manufacturing method according to any of the preceding or following aspects, wherein on the first spray pipe, the horizontal spacing between two adjacent second spray pipes is 640-1300 mm (preferably 700-1200 mm), and / or, on the same second spray pipe, the horizontal spacing between two adjacent third spray pipes is 320-650 mm (preferably 350-600 mm).

[0031] 22. The production method according to any one of the preceding or following aspects, wherein in the cooling step, the spraying liquid contacts the reaction product in a countercurrent manner.

[0032] 23. The production method according to any one of the preceding or following aspects, wherein the inner diameter of the absorption device is 4.5-11.5 m (preferably 4.8-10.5 m).

[0033] 24. The manufacturing method according to any one of the preceding or following aspects, wherein the gas inlet is located below the spraying device along the central axis of the absorption device.

[0034] 25. The production method according to any of the preceding or following aspects, wherein in the reaction step, the hydrocarbon feedstock is propylene, the molar ratio of propylene / ammonia / air (calculated as molecular oxygen) is 1:1.1-1.3:1.8-2.0, the reaction temperature is 420-440°C, the reaction pressure (gauge pressure) is 0.03-0.14 MPa, and the catalyst weight hourly space velocity is 0.06-0.15 h -1 Alternatively, the hydrocarbon feedstock is isobutylene, the molar ratio of isobutylene / ammonia / air (as molecular oxygen) is 1:1.3-1.6:2.2-2.8, the reaction temperature is 395-420°C, the reaction pressure (gauge pressure) is 0.03-0.14 MPa, and the catalyst weight hourly space velocity is 0.08-0.17 h -1 .

[0035] 26. The manufacturing method of any of the preceding or following aspects, wherein during the cooling step, the spraying liquid cools the temperature of the reaction product from 195-235°C to 81-86°C, and / or, during the cooling step, the spraying liquid reduces the ammonia content of the reaction product to below 150 ppm.

[0036] 27. The absorption device according to any one of the preceding or following aspects, wherein the rotation direction A is clockwise and the rotation direction B is counterclockwise.

[0037] Technical Effects

[0038] According to the present invention, even if the operation is carried out for a long period (such as continuous operation for 18 months or even longer), the ammonia content in the absorbed exhaust gas does not increase significantly compared with the initial operation period, and a good ammonia absorption effect can be maintained for a long period of time, thereby reducing ammonia escape.

[0039] According to the present invention, even in long-term operation (such as continuous operation for 18 months or even longer), the total acid consumption can still be maintained at a low level with a small increase (such as below 3%).

[0040] According to the present invention, ammonia gas is evenly distributed in the absorption tower, which is beneficial to ammonia absorption.

[0041] According to the present invention, the gas-liquid contact is sufficient, the ammonia absorption effect is good, and the amount of acid used can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1 is a schematic front view of an ammonia absorption tower in the prior art.

[0043] FIG2 is a schematic front view of an ammonia absorption tower in the prior art.

[0044] 3a and 3b are schematic front views of the ammonia absorption tower of the present invention.

[0045] 4A and 4B are schematic front views of an ammonia absorption tower according to the present invention.

[0046] FIG5 is a schematic top view of the spraying device of the present invention.

[0047] 6A and 6B are schematic top views of the spraying device of the present invention.

[0048] FIG7 is a schematic top view of the spraying device of the present invention.

[0049] 8A and 8B are schematic top views of comparative spraying devices.

[0050] 9A and 9B are schematic top and front views of a nozzle in the prior art.

[0051] 10A and 10B are a schematic top view and a detailed top view of a spraying device in the prior art.

[0052] Figure 11A is a schematic diagram of the top view and front view of the nozzle of the present invention in two rotation modes. Figure 11B is a schematic diagram of the top view of the spraying device.

[0053] Figure 11C is a detailed view of a top view of a spraying device according to the present invention. Figure 11D is a detailed view of a top view of another spraying device according to the present invention. Figure 11E is a detailed view of a top view of another spraying device according to the present invention.

[0054] Explanation of the accompanying drawings: 1: Ammonia absorption tower 2: Ammonia absorption tower internal component demister 3: Ammonia absorption tower internal component spraying device, 3a-3f are spraying devices 4: Ammonia absorption tower internal component gas distributor 5: Ammonia absorption tower internal component spraying device, 5a-5b are spraying devices 6: Upper section circulating pump 7: Lower section circulating pump 8: Ammonia-containing gas feed 9: Ammonia absorber gas phase discharge 10: Upper section water replenishment 11: Lower section wastewater discharge 12: Upper section ammonium salt solution discharge 13: Lower section circulating liquid 14: Upper section circulating liquid 15: Acid-containing solution 16: Circulating liquid 17: Circulating pump 18: Spraying device inlet 19: Spraying device first spray pipe 20a, 20b: Spraying device second spray pipe 21: Spraying device third spray pipe 22: Spraying device atomizing nozzle 23: Gas distributor P1, P2, P3, P4, P5, P6: Spraying device spray liquid inlet pressure. DETAILED DESCRIPTION

[0055] The specific embodiments of the present invention are described in detail below. However, it should be noted that the protection scope of the present invention is not limited by these specific embodiments, but is determined by the claims in the appendix.

[0056] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In the event of conflict, the definitions in this specification will prevail.

[0057] When this specification uses the prefix "well known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, the objects introduced by the prefix include those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become generally recognized in the art to be suitable for similar purposes.

[0058] In the context of this specification, by substantially it is meant that the deviation does not exceed 10%, preferably does not exceed 5% or 2%.

[0059] In the context of this specification, the method for measuring the extinction coefficient is forward near-infrared scattering spectroscopy. In the strong radiation area of ​​the visible light range, a near-infrared LED light source is used to irradiate a sample volume of about 100 ml, and the scattered light intensity I(θ) in the forward range of 25°-45° is measured. The extinction coefficient σ is then calculated using the formula σ=I(θ) / k, where k is the scattering extinction ratio, which can be calibrated by a high-precision transmissometer.

[0060] In the context of this specification, the average droplet diameter D 32The measurement method is based on laser imaging to measure the plane droplet size, and obtain the 2D spatially resolved average particle size D from the droplet image information. 32 To measure the global droplet size, it is necessary to simultaneously record the laser-induced fluorescence (LIF) signal and the Mie-type scattering (MIE) image of the droplet being measured. The two-dimensional Schad average particle size is calculated by the ratio of these two image signals. The LIf image represents the volume of the droplet, and the MIE light is basically proportional to the total amount of the droplet.

[0061] D 32 = Total droplet volume / Total droplet area=LIf signal / MIE signal.

[0062] In the context of this specification, the droplet size distribution is measured as the average droplet diameter D 32 The measurement method is the same, based on laser imaging to measure the droplet size distribution, and obtain the 2D spatially resolved particle size distribution D from the droplet image information. 10 、D 50 、D 90 wait.

[0063] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this specification are based on weight and pressure is gauge pressure.

[0064] In the context of this specification, any two or more embodiments of the present invention may be arbitrarily combined, and the technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the scope of protection of the present invention.

[0065] In the context of this specification, all technical details not mentioned are directly applicable to relevant information known in the art.

[0066] According to one embodiment of the present invention, it relates to a method for producing a nitrile, in particular a method for producing (meth)acrylonitrile.

[0067] According to one embodiment of the present invention, the manufacture method of the nitrile comprises making hydrocarbon feedstock generation ammoxidation reaction and manufacturing the step (referred to as reaction step) of the reaction product comprising nitrile and introducing the reaction product into an absorption device through a gas inlet and spraying a spray liquid to cool the reaction product and forming an absorption atmosphere in the absorption device by a spraying device. In the art, the absorption device is generally also referred to as an ammonia absorber or a quench tower.

[0068] According to the present invention, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.004-0.02 m -1 (Preferably 0.006-0.018m -1). The inventors of the present invention have discovered that, since the droplets produce strong attenuation of both visible light and infrared signals, by measuring the attenuation of light and calculating its extinction coefficient, it can be used to comprehensively evaluate the dispersion effect of the liquid after being ejected at high speed through the nozzle. For equal amounts of liquid that are broken up into several small droplets after passing through the nozzle, generally, the larger the droplet size, the smaller the number of droplets, the smaller the absorption of light, the higher the light transmittance, and the smaller the extinction coefficient, and vice versa. A small extinction coefficient means that the droplet size is large and the number is small, and the total surface area of ​​these droplets is relatively small. Due to the insufficient area of ​​contact with gaseous ammonia, the ammonia absorption efficiency decreases, resulting in more ammonia penetration. Conversely, a large extinction coefficient means that the droplet size is small and the number is large, and these droplets with too small a particle size are entrained by the gas and move upward, and are easily taken away from the tower. In the ammonia absorption tower, the ammonium salts contained in the droplets are carried by the gas to the subsequent process, which will increase the environmental burden, which is also to be avoided as much as possible.

[0069] According to a preferred embodiment of the present invention, when measured at a vertical distance of 3000 mm above the gas inlet, the average diameter of the droplets of the absorption atmosphere D 32 The average particle size of the droplets is preferably 400-2600 microns (preferably 600-2400 microns). The inventors of the present invention have discovered that the moment the liquid is ejected from the nozzle, the liquid film is torn into small droplets. When the small droplets collide with other droplets during their fall, they may separate, aggregate, or break. The average particle size of the droplets can be measured optically. When the average particle size of the droplets is greater than 2600 mm, on the one hand, due to the effect of gravity, the faster the droplets move downward, the significantly shorter the droplet residence time in the tower is, which can easily lead to a decrease in absorption efficiency due to insufficient contact time with the gas. On the other hand, of two droplets of the same volume, the surface area of ​​a large-particle droplet is smaller than the surface area of ​​the two small-particle droplets. That is, relative to the two small droplets, a large-particle droplet has less opportunity to contact the gas, which can also lead to a decrease in absorption efficiency. When the average droplet size is less than 400 mm, the upward lifting force of the gas on the droplets overcomes the gravity of the droplets themselves, making the droplets more easily entrained. At the same time, more power is required, such as the inlet pressure of the spraying device, so that the liquid is torn smaller when it is sprayed through the nozzle.

[0070] According to a preferred embodiment of the present invention, when measured at a vertical distance of 3000 mm above the gas inlet, the droplet size distribution of the absorption atmosphere is D 10 150-1500 microns, D 50 700-3000 microns, D 90 1400-3600 microns (preferably D 10 250-1400 microns, D 50 800-2800 μm, D 90The inventors of the present invention have discovered that after a liquid is ejected from a nozzle, it is torn into numerous small droplets of varying sizes. Furthermore, during the collision of two droplets, the particle sizes may increase due to aggregation, decrease due to fragmentation, or remain unchanged. In a specific embodiment, the circulating liquid is an acid-containing liquid, and the absorption atmosphere is an ammonia-containing gas. The acid in the droplets absorbs ammonia in the gas phase to form ammonium salts that exist in the droplets. If the droplet D 10 and / or D 50 and / or D 90 Smaller, which means that the droplet D 32 Small droplets containing ammonium salts are easily entrained by gases and escape from the tower, which brings new problems to the subsequent process. For example, if the circulating liquid contains sulfuric acid, SO2-containing gas will be generated in the incineration of wastewater. If the circulating liquid contains phosphoric acid, P2O5 will be produced. These are all unfriendly to the environment and should be avoided as much as possible.

[0071] According to a further preferred embodiment of the present invention, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.001-0.004 m -1 (Preferably 0.0015-0.0035m -1 The inventors of the present invention found that the measurement position is located above the spray device of the absorption tower. The droplets in this area are entrained by gas. Compared with the droplet size at the aforementioned measurement position, the droplet size in this area is relatively small, and the amount of gas entrainment is also within a controllable range. When the extinction coefficient of the absorption atmosphere is less than 0.001m -1 When the droplet size in the spraying device area is too large, the upward thrust of the gas is less than its gravity, resulting in a small amount of droplet entrainment. The droplet size in the spraying device area is too large, the gas-liquid contact is insufficient, and it is easy to cause the absorption atmosphere (such as ammonia) to penetrate. When the extinction coefficient is greater than 0.004m -1 When the droplet size is normal, it means that the number of droplets entrained by the gas is large, and there is a possibility that the gas passes through the tower at a high speed. The gas does not stay in the tower for enough time, resulting in incomplete absorption and low efficiency, causing the absorption atmosphere (such as ammonia) to penetrate.

[0072] According to a preferred embodiment of the present invention, when measured at a vertical distance of 8500 mm above the gas inlet, the average diameter of the droplets of the absorption atmosphere D 32 More preferably, when measured at a vertical distance of 8500 mm above the gas inlet, the droplet size distribution of the absorption atmosphere is D 10 100-1000 microns, D 50 300-1800 μm, D 90500-2200 microns (preferably D 10 200-600 microns, D 50 400-1400 μm, D 90 The inventors of the present invention found that the average diameter of the droplets measured at the measuring position D 32 and the droplet size distribution and the average droplet diameter D in the spraying device area 32 It is closely related to the droplet size distribution. Usually the average droplet diameter D in the spraying device area is 32 Large, the average diameter of the droplets in this area is D 32 The droplet size distribution is also relatively large. When the average droplet diameter and droplet size distribution are below the lower limit, it means that the droplets in the spraying device area are too small and the droplets are easily entrained. Conversely, when the average droplet diameter and droplet size distribution are above the upper limit, the droplets in the spraying device area are too large, the gas-liquid contact is insufficient, and the absorption efficiency is reduced.

[0073] According to one embodiment of the present invention, the spraying device includes a spray liquid inlet, a first spray pipe fluidically connected to the spray liquid inlet, a plurality of (e.g., 10-26, preferably 12-22) second spray pipes fluidically connected to the first spray pipe and extending perpendicularly to the first spray pipe on both sides thereof, a plurality of (e.g., 4-26, preferably 6-22) third spray pipes fluidically connected to the second spray pipe and extending perpendicularly to the second spray pipe on both sides thereof, and a nozzle located at the end of the third spray pipe and fluidically connected thereto.

[0074] The present invention does not specifically limit the connection method between the spray pipes and between the third spray pipe and the nozzle, and conventional connection methods in the art may be used. For example, a fixed connection or a detachable connection may be used, preferably a threaded connection, or other detachable connection methods are not specifically limited.

[0075] According to one embodiment of the present invention, the spraying liquid is water or an acidic aqueous solution. Preferably, the ammonia-containing gas contacts the acidic aqueous solution serving as the spraying liquid from bottom to top in reverse, with the acidic H+ contained in the aqueous solution reacting with the ammonia to neutralize and remove the ammonia. Here, the acidic aqueous solution is an aqueous solution of an acidic substance. The acidic substance may be an inorganic acid such as hydrochloric acid, sulfuric acid, or phosphoric acid; an organic acid such as acrylic acid or acetic acid; or an acidic salt such as ammonium sulfate, without specific limitations.

[0076] According to one embodiment of the present invention, in the cooling step, the spraying liquid contacts the reaction product in a countercurrent manner.

[0077] According to one embodiment of the present invention, in the cooling step, the spray liquid input pressure at the spray liquid inlet is controlled at 0.06-1.00 MPaG (preferably 0.12-0.90 MPaG, more preferably 0.18-0.80 MPaG). The inventors of the present invention found that the circulating liquid enters the spray device from the spray device inlet, passes through the first spray pipe, the second spray pipe, the third spray pipe, and is transported to the absorption tower through the nozzle at the end of the third spray pipe. Generally, the larger the droplet size, the weaker the droplet's absorption of light, and the extinction efficiency will also decrease. The droplet size is inversely proportional to the pressure. Since the pressure gradually decreases along the direction of fluid travel, the droplet size continues to increase along the direction of circulation of the circulating liquid fluid. The droplet size D formed at the atomizing nozzle far away from the spray inlet in the direction of fluid travel is smaller than the droplet size D. 32 Greater than the droplet size D formed at the atomizing nozzle near the spray inlet in the direction of fluid travel 32 , which results in the ammonia absorption efficiency at the far end of the fluid flow direction from the spray inlet being lower than the ammonia absorption efficiency at the near end of the fluid flow direction from the spray inlet. The spray liquid input pressure at the spray liquid inlet is controlled within the aforementioned specified range to meet the sufficient pressure at the distal nozzle, meet the average droplet particle size and particle size distribution requirements required by the device, and ensure the atomization effect. In addition, as the device runs for a long time, the polymer with a certain viscosity produced during the reaction and the ammonium salt mixed in the circulating liquid adhere to the wall of the spray pipe, resulting in a continuous increase in the resistance of the pipe side. In particular, after the device has been running for 18 months, the increase in the resistance of the pipe side is more obvious, and the pressure at the distal nozzle is further reduced, resulting in larger droplet size at the distal nozzle, and the droplet particle size distribution becomes wider and more uneven, and the atomization effect is worse. According to the present invention, by controlling the spray liquid input pressure at the spray liquid inlet within the aforementioned specified range, even after a long period of continuous operation, sufficient pressure at the distal nozzle can be met to ensure the atomization effect.

[0078] According to one embodiment of the present invention, the plurality of second spraying pipes extend perpendicularly to the first spraying pipe and substantially in parallel along a horizontal direction toward opposite sides thereof.

[0079] According to one embodiment of the present invention, the plurality of third spraying pipes extend perpendicularly to the second spraying pipe and substantially in parallel along a horizontal direction toward opposite sides thereof.

[0080] According to one embodiment of the present invention, the inner diameter of the first spray pipe is 160-480 mm (preferably 200-450 mm), and the length is 4500-11500 mm (preferably 4800-10500 mm).

[0081] According to one embodiment of the present invention, the plurality of second spray pipes are the same as or different from each other, and each has an independent inner diameter of 30-150 mm (preferably 40-120 mm) and an independent length of 1200-5750 mm (preferably 1800-5250 mm).

[0082] According to one embodiment of the present invention, the plurality of third spray pipes are the same as or different from each other, and each independently has an inner diameter of 10-60 mm (preferably 15-50 mm) and a length of 160-325 mm (preferably 175-300 mm).

[0083] According to one embodiment of the present invention, the nozzle includes a nozzle inlet, a rotation chamber, and a nozzle outlet, wherein the rotation chamber is configured such that the spray liquid entering from the nozzle inlet exits the nozzle outlet in a rotating manner after passing through the rotation chamber. According to the present invention, the rotation chamber can adopt any structure known in the art, as long as the spray liquid exits the nozzle outlet in a rotating manner after passing through the rotation chamber, without particular limitation.

[0084] According to one embodiment of the present invention, the nozzles are identical or different from each other, and the inner diameter (referring to the nozzle outlet) is independently 3-20 mm (preferably 6-14 mm), the diameter of the rotating chamber is independently 10.0-55.0 mm (preferably 13.0-45.0 mm), and the spraying angle is independently 65-120° (preferably 70-100°). According to the present invention, the rotating chamber can adopt any structure known in the art, as long as the spray liquid can leave the nozzle outlet in a rotating manner after passing through the rotating chamber, and there is no particular limitation.

[0085] According to one embodiment of the present invention, on the first spray pipe, the horizontal distance between two adjacent second spray pipes is 640-1300 mm (preferably 700-1200 mm).

[0086] According to one embodiment of the present invention, on the same second spraying pipe, a horizontal distance between two adjacent third spraying pipes is 320-650 mm (preferably 350-600 mm).

[0087] According to one embodiment of the present invention, on two adjacent second spray pipes, the straight-line distance M between the end of any third spray pipe on one second spray pipe and the end of any third spray pipe on the other adjacent second spray pipe (as shown in Figures 6A and 6B) is not less than 320 mm, and preferably not less than 350 mm. The inventors of the present invention have discovered that in order to improve the ammonia absorption efficiency, generally, at any position on the cross-section of the tower, at least two or more conical liquid surfaces formed with the nozzle as the center overlap, including at the tower wall. If the distance between the two spray pipe ends is too large, due to the limitations of the nozzle structure, it is difficult for any position on the tower wall to meet the requirement of overlapping liquid surfaces sprayed by two or more nozzles. In other words, the number of droplets in the tower is reduced, which is manifested as a decrease in the droplet's light absorption rate and a weakened extinction ability, thereby increasing the probability of ammonia escaping from the "gap". If the distance between the two spray pipe ends is too small, in order to ensure the atomization quality of the spray liquid, the circulating liquid volume in the ammonia absorption tower will inevitably increase, that is, the energy consumption of the pump will increase. In addition, as shown in FIG6A and FIG6B , if the upper and lower multi-layer spraying devices are overlapped in upper and lower projections, only the upper spraying device and the spraying liquid inlets facing each other can be seen.

[0088] According to one embodiment of the present invention, the nozzles are the same as or different from each other, and the spraying liquid spraying rate of each nozzle is independently 0.5-7.5 t / h (preferably 0.9-6.5 t / h).

[0089] According to a preferred embodiment of the present invention, the nozzles are identical or different, and the spray liquid discharge pressure at the nozzle outlet is independently 0.03-0.85 MPaG (preferably 0.04-0.65 MPaG). The inventors of the present invention have discovered that for the atomizing nozzles of the ammonia absorber, pressure is one of the main factors that prompt the liquid to form droplets. Within a certain pressure range, the size of the droplet particle size increases as the pressure decreases. Compared with large atomized droplets, small atomized droplets are generally considered to have better mass and heat transfer efficiency. Generally, the smaller the droplets, the narrower the particle size distribution, the greater the light absorption, and the stronger the extinction energy. When the spray pressure at the nozzle outlet is less than 0.03 MPaG, the acidic circulating fluid is poorly atomized after passing through the spray device, and the droplet size is large, indicating insufficient contact with ammonia. When the spray pressure at the nozzle outlet is greater than 0.85 MPaG, although the acidic circulating fluid is well atomized after passing through the spray device, the droplet size is too small, and the liquid is easily entrained out of the ammonia absorber by gas, and the ammonium salt dissolved in the liquid causes unnecessary trouble to subsequent processes. In addition, as the device operates for a long time, the viscous polymers produced during operation also adhere to the nozzle cavity, increasing the nozzle resistance and causing a decrease in pressure at the nozzle outlet. For example, after 18 months of continuous operation, dirt adheres to the nozzle cavity, changing the movement of the spray liquid in the nozzle and, in particular, increasing the instability of the atomization of the distal nozzle. This instability becomes more prominent as the device operates for a longer time. According to the present invention, by controlling the spraying pressure of the spray liquid at the nozzle outlet within the aforementioned specified range, the atomization condition of the distal nozzle can be kept stable and the atomization effect can be guaranteed even after a long period of continuous operation.

[0090] According to one embodiment of the present invention, in the cooling step, the spraying liquid contacts the reaction product in a countercurrent manner.

[0091] According to one embodiment of the present invention, in the cooling step, the mass flow ratio of the spraying liquid to the reaction product is 15-25:1.

[0092] According to one embodiment of the present invention, the cooling step is carried out in the absorption device, and a plurality of (such as 2-10, preferably 4-8) spraying devices are layered inside the absorption device at predetermined vertical intervals along the central axis direction of the absorption device.

[0093] According to one embodiment of the present invention, when the absorption device is cut perpendicularly to its central axis to obtain a cross-section, the projections of at least one (preferably all) of the first, second, and third spray pipes of one of the plurality of spray devices and another of the plurality of spray devices on the cross-section substantially overlap. That is, the projections of the nozzles (cone centers) of each layer on the cross-section overlap, thereby ensuring uniform distribution of ammonia in the gas passage.

[0094] According to one embodiment of the present invention, the projections of all nozzles of the one spraying device and the other spraying device on the cross section substantially overlap. The inventors of the present invention discovered that the multiple spraying devices in the absorption device are both relatively independent individuals and an organic whole. The circulating liquid is transported to the nozzles of each spraying device through the first, second, and third spraying pipes of each spraying device, and a hollow conical liquid surface is formed with the nozzle as the center. The gas and the circulating liquid come into contact in reverse. The gas can only come into contact with the conical liquid surface formed by the upper spraying device after passing through the conical liquid surface formed by the lower spraying device. At the moment the gas passes through the conical liquid surface, the ammonia in the gas and the acid in the liquid undergo a neutralization reaction. As the ammonia-containing gas passes through the multiple hollow conical liquid surfaces of the multiple spraying devices, it is eventually completely neutralized by the acid in the circulating liquid. The area between the hollow conical liquid surfaces of the upper and lower spraying devices can be regarded as a gas rising channel. Since each section is required to have an independent liquid phase circulation spraying device, the rising gas channel has a certain height. The projections of at least one (preferably all) of the first spray pipe, the second spray pipe and the third spray pipe on the cross section basically overlap, that is, the projections of the nozzles (center of the cone) of each layer on the cross section overlap, so that ammonia is evenly distributed in the gas channel, the fusion with the droplets is more complete, and the extinction efficiency is more consistent. If the projections of the upper layer nozzle and the lower layer nozzle on the cross section do not overlap, since the hollow cone liquid levels of the upper and lower layers are not in the same position, the gas channel of the rising gas is changed. After the rising gas passes through the gas channel, due to the different extinction efficiencies on different channels, there is a problem of uneven gas distribution between the gas channels, which reduces the ammonia absorption effect. According to one embodiment of the present invention, the vertical spacing between two adjacent spray devices (measured by the vertical spacing of the spray liquid inlet of the spray device) is 650-1350mm, preferably 750-1200mm.

[0095] The inventors discovered that if the cross-sectional projections of the upper and lower nozzles do not overlap, the hollow conical liquid surfaces of the upper and lower layers are not in the same position, which alters the gas path of the rising gas. Some channels become wider, while others become narrower. A wider channel also means fewer droplets flow through it, reducing extinction efficiency. Conversely, a narrower channel increases extinction efficiency. As the rising gas passes through gas channels at different heights, the varying residence times within the channels can lead to uneven gas distribution. This means that as the ammonia-containing gas passes through the hollow conical liquid surface, some areas of the liquid surface may have excess acid, while others, lacking acid, allow ammonia to penetrate, reducing ammonia absorption.

[0096] The inventors of the present invention have also discovered that if the cross-sectional projections of the nozzles in the upper and lower layers do not overlap, the spray liquids from the upper and lower layers of nozzles will collide more frequently. When two droplets collide, they may separate, coalesce, or break apart. The inventors have discovered that when the cross-sectional projections of the nozzles in the upper and lower layers do not overlap, the droplets produced by the upper and lower layers of nozzles are more likely to coalesce during collision, forming larger droplets. This also reduces the number of droplets, resulting in a decrease in extinction efficiency, which is detrimental to ammonia absorption.

[0097] The inventors of the present invention further discovered that as the circulating fluid of each spray device flows along the first spray pipe, the second spray pipe, the third spray pipe, and finally the nozzle, the fluid is affected by the resistance of the pipe wall during flow, and the pressure continuously decreases along the way. The pressure at the nozzle far from the spray liquid inlet is lower than the pressure at the nozzle near the spray liquid inlet. Because the pressure at the farthest nozzle is relatively low, the average particle size of the droplets here is relatively large, the droplet size distribution is wider, the droplet absorption efficiency is the lowest, and the atomization effect is also the worst. This leads to insufficient gas-liquid contact at the farthest nozzle, which easily causes ammonia escape. As the operating cycle of the device increases, such as the device operates continuously for 18 months or even longer, solid impurities and heavy components with higher viscosity in the pipeline adhere to the pipe wall, further increasing the pipe wall resistance, further reducing the droplet absorption efficiency, that is, the extinction efficiency, and further reducing the atomization effect at the far nozzle, causing more ammonia escape. If the spray liquid inlets of the multi-layer spray devices are on the same side, since the distal nozzles of the spray devices of each layer are on the same side, the gas-liquid contact in this area is weakest, and ammonia in the gas phase is more likely to escape from the ammonia absorption tower from this area.

[0098] Based on these findings, according to one embodiment of the present invention, the angle between the projections of the spray liquid inlets of the one spray device and the other spray device on the cross section is 180°. In the initial stage of device operation, since the spray device pipeline is relatively clean, the distal nozzle of the spray device is sufficient to atomize the spray liquid into droplets of appropriate size. After the device has been in continuous operation for 18 months or even longer, although ammonia escapes from the distal nozzle of one spray device due to poor nozzle atomization and poor gas-liquid contact due to poor nozzle atomization effect, the escaped ammonia is captured by the spray liquid at the proximal nozzle of the upper spray device and undergoes a neutralization reaction to generate corresponding salts. The average droplet size and droplet size distribution in the inlet end position area of ​​the upper and lower opposing spray devices are similar, that is, the extinction efficiency is similar. Usually, multiple layers of spraying devices are set in the ammonia absorption tower, such as 3 layers, 4 layers, 5 layers or more layers. The projected angle between the spraying liquid inlet of the upper (or second) layer of spraying device and the spraying liquid inlet of the lower (or second) layer of spraying device on the cross section is 180°, which can absorb ammonia to a greater extent, thereby reducing ammonia escape and also reducing acid consumption to a greater extent.

[0099] According to one embodiment of the present invention, the two nozzles whose projections substantially coincide with each other have the same spray diameter.

[0100] According to one embodiment of the present invention, among all the spray devices, the angle between the projections of the spray liquid inlets of any two odd-numbered spray devices on the cross section is 0°, the angle between the projections of the spray liquid inlets of any two even-numbered spray devices on the cross section is 0°, and the angle between the projections of the spray liquid inlets of any odd-numbered spray device and any even-numbered spray device on the cross section is 180°. The inventors of the present invention have discovered that this arrangement can ensure the most uniform distribution of ammonia in the gas phase in the gas channel.

[0101] According to one embodiment of the present invention, two nozzles with substantially overlapping projections have the same spray liquid rotation direction. The inventors of the present invention discovered that when the spray liquids ejected from the nozzles of the two spraying devices with overlapping projections collide downward, the droplet states of each nozzle are different. Relatively speaking, two nozzles with overlapping projections but opposite rotation directions are more likely to cause droplets to break into several small droplets than two nozzles with the same rotation direction, thereby enhancing light absorption and extinction efficiency. However, if the droplets are too small, they are easily entrained by gas and escape.

[0102] According to one embodiment of the present invention, on at least one (preferably all) of the second spray pipes, two adjacent (preferably all) nozzles located on the same side of the second spray pipe are constructed so that the spray liquid is sprayed in the same rotational direction. The inventors of the present invention discovered that the spray liquid enters the rotating nozzle from the tangential direction of the nozzle and forms a hollow cone with the nozzle outlet as the vertex after passing through the nozzle outlet. In order to ensure the uniformity of the spray liquid in the tower, the nozzle outlets of the two adjacent nozzles are required to be equidistantly distributed in the cross-section of the tower, that is, the spray liquid enters the nozzle from the same tangential direction. Therefore, the spray liquid on the same side of the second spray pipe is sprayed in the same rotational direction, while the spray liquid on opposite sides of the second spray pipe is sprayed in opposite rotational directions. In this way, after the spray liquid sprayed from the nozzles on the same second spray pipe intersects and collides, more droplets remain in the same light absorption state and continue to move downward in the original direction.

[0103] According to one embodiment of the present invention, all nozzles on the opposite sides of two adjacent second spray pipes are configured to spray liquid in opposite rotational directions. Here, "adjacent to each other" refers to being on the same side of the first spray pipe and adjacent to each other, while "opposite sides" refers to the sides of one second spray pipe and the other second spray pipe facing each other, as shown in Figure 11C. After the spray liquid ejected from two adjacent nozzles of the adjacent second spray pipes collides during their downward movement, the droplets can maintain their original state and move downward. The droplets are unlikely to aggregate and grow larger, nor are they likely to break into smaller droplets.

[0104] According to one embodiment of the present invention, on at least one (preferably all) of the second spray pipes, at least one (preferably all) nozzles located on one side of the second spray pipe are configured to spray the spray liquid in a rotation direction A, and at least one (preferably all) nozzles located on the other opposite side of the second spray pipe are configured to spray the spray liquid in a rotation direction B, wherein the rotation direction A is opposite to the rotation direction B.

[0105] According to one embodiment of the present invention, the rotation direction A is clockwise, and the rotation direction B is counterclockwise.

[0106] According to one embodiment of the present invention, among all the nozzles of the spraying device, the number of nozzles that spray the spray liquid in the rotation direction A is equal to or substantially equal to the number of nozzles that spray the spray liquid in the rotation direction B. As mentioned above, the premise of uniform spraying is that the nozzles are evenly distributed in the tower, and usually an axisymmetric distribution is preferred. Therefore, the inventors of the present invention found that the rotation directions of the nozzles appear in pairs with axisymmetry. If the rotation directions of the paired nozzles are all in the same direction, it means that the rotation directions of all nozzles are the same, which easily causes the spray liquid sprayed from two adjacent nozzles to rotate and descend. The droplet collision becomes larger, the extinction efficiency becomes weaker, and the ammonia absorption efficiency is reduced due to the reduction of the total effective contact area with the gaseous ammonia.

[0107] According to one embodiment of the present invention, on at least one (preferably all) of the second spray pipes, two adjacent (preferably all) nozzles located on the same side of the second spray pipe are configured so that the spray liquid is sprayed in opposite rotational directions. A third spray pipe is perpendicular to the second spray pipe and extends horizontally parallel to both sides thereof. All nozzles on the same horizontally parallel extension line of the second spray pipe are configured so that the spray liquid is sprayed in the same rotational direction. This is shown in Figure 11E.

[0108] According to one embodiment of the present invention, on at least one (preferably all) of the second spray pipes, one nozzle located in the second spray pipe is configured to spray the spray liquid in a rotational direction A, and at least another nozzle adjacent on one side is configured to spray the spray liquid in a rotational direction B. At least one (preferably all) nozzles located on the opposite other side of the second spray pipe are configured to spray the spray liquid in a rotational direction A, wherein the rotational direction A is opposite to the rotational direction B.

[0109] According to one embodiment, the nozzle includes a nozzle inlet, a nozzle cavity, and a nozzle outlet. The cavity has a special structure that allows the spray liquid entering the nozzle inlet to form droplets after passing through the cavity and exiting the nozzle outlet. As shown in Figure 9, the cavity can adopt any structure known in the art, as long as it can allow the spray liquid to exit the nozzle outlet and form droplets, and there are no specific limitations.

[0110] According to one embodiment, the spray liquid enters the cavity from above the nozzle and forms a solid cone with the nozzle outlet as the vertex after passing through the nozzle outlet. Usually, two adjacent nozzles are equidistantly distributed in the cross section of the tower, and the projections of the nozzles of multiple spraying devices basically overlap. After the spray liquids sprayed from two adjacent nozzles collide in their respective downward processes, the droplets can still maintain their original state and move downward.

[0111] According to one embodiment of the present invention, the vertical spacing between two adjacent spraying devices (measured by the vertical spacing of the spraying liquid inlet of the spraying device) is 650-1350 mm (preferably 750-1200 mm). The inventors of the present invention have found that when the vertical spacing between two adjacent spraying devices is less than 650 mm, for an ammonia absorption tower with the same number of spraying devices, due to insufficient contact time between the rising ammonia-containing gas and the descending circulating liquid, the gas-liquid fusion becomes poor, the extinction efficiency decreases, and part of the ammonia in the gas phase directly passes through the hollow conical liquid surface formed by the circulating liquid, resulting in poor ammonia absorption efficiency. Although sufficient gas-liquid contact time can be met by increasing the number of spraying devices to achieve complete absorption of ammonia in the gas phase, the total amount of circulating liquid will increase, and the energy consumption of the pump will increase, which is obviously uneconomical. When the vertical spacing between two adjacent spraying devices is greater than 1350 mm, under the condition of the same spraying device, the height of the tower will increase, that is, the equipment investment cost will increase, and in addition, the difficulty of maintenance will be increased.

[0112] According to one embodiment of the present invention, the difference (absolute value) in the spray liquid input pressure at the spray liquid inlets of any two of the spray devices is less than 0.024 MPa (preferably less than 0.018 MPa, more preferably less than 0.012 MPa). The inventors of the present invention have discovered that the size of the circulating liquid droplets after atomization is closely related to the pressure at the nozzle. Excessive or insufficient pressure is detrimental to the operation of the device. The nozzle pressure starts from the spray liquid input pressure at the spray liquid inlet. Theoretically, it is desirable that the spray liquid input pressures at the spray liquid inlets be the same. However, in reality, due to the vertical arrangement of the multi-layer spray devices, the circulating pump suffers from pressure drop loss when transporting the circulating liquid to the spray devices on each layer. Therefore, the difference in spray liquid input pressure at the spray liquid inlets of any two spray devices should be as low as possible so that all nozzles of the top and bottom spray devices meet the optimal pressure conditions, and the average droplet diameter and droplet size distribution on the longitudinal cross-section of the device are similar, that is, the extinction efficiency in the longitudinal direction of the device is also the same.

[0113] According to one embodiment of the present invention, the inner diameter of the absorption device is 4.5-11.5 m (preferably 4.8-10.5 m).

[0114] According to one embodiment of the present invention, the absorption device further comprises a housing and a gas inlet. According to the present invention, the spraying device is disposed inside the housing of the absorption device. In addition, the reaction product is fed into the absorption device through the gas inlet.

[0115] According to one embodiment of the present invention, the gas inlet is located below the spraying device along the central axis of the absorption device.

[0116] According to one embodiment of the present invention, the vertical distance between the gas inlet and the spray liquid inlet of the spraying device (when there are multiple ones, it refers to the spraying device closest to the gas inlet) is 800-6000mm (preferably 1000-5000mm). The inventors of the present invention found that the gas enters the tower from the inlet along the semicircular inlet pipe that bends downward toward the bottom of the tower, and then moves from bottom to top. Relatively speaking, the gas concentration is highest at the inlet pipe. While the gas is going up, due to the difference in gas concentration, the gas diffuses to the surrounding area, and finally the gas concentration on the cross section of the tower reaches a uniform level. If the vertical distance is less than 800mm, the gas concentration is prone to insufficient diffusion, the concentration is inconsistent, the gas-liquid separation is uneven, which affects the uneven extinction efficiency and easily causes incomplete local ammonia absorption and excessive local acid. If the vertical distance is too large, on the one hand, the tangent height of the ammonia absorption tower is too high, which increases equipment investment. On the other hand, during the rotating and falling spray, the colliding droplets may separate, aggregate, and break up. Aggregation forms larger droplets, while breakup forms smaller droplets. The longer the droplet spray distance, the more likely it is to aggregate or break up, resulting in a wider droplet size distribution and a potential decrease in extinction efficiency, which is also detrimental to ammonia absorption.

[0117] According to one embodiment of the present invention, the inner diameter of the gas inlet is 800-1900 mm (preferably 900-1700 mm).

[0118] According to one embodiment of the present invention, the linear velocity of the gas inside the shell is 0.6-1.5m / s (preferably 0.7-1.3m / s). The inventors of the present invention have found that the operating speed inside the shell affects the gas diffusion speed. The greater the operating speed inside the shell, the stronger the turbulent effect, the more entrained droplets, the higher the extinction efficiency, and the diffusion of the gas. Therefore, the diffusion distance is also shorter. When the speed inside the shell is lower than 0.6, relatively speaking, it takes a long time for the gas to diffuse uniformly, that is, the distance from the inlet to the first layer of spraying device increases. However, when the linear velocity inside the shell is higher than 1.5m / s, since the droplets of the spraying liquid of the spraying device are usually in the shape of droplets, these droplets are easily entrained by the gas. The greater the speed inside the shell, the more serious the entrainment phenomenon is, resulting in more droplets containing ammonium salts being taken away from the ammonia absorption tower by the gas.

[0119] According to one embodiment of the present invention, the internal space of the absorption device between the gas inlet and the spraying device (if multiple are present, the spraying device closest to the gas inlet) is free of mechanical components that could substantially affect the flow of the gas, such as mechanical components that disturb the gas flow, particularly baffles, trays, and packing. The inventors of the present invention have discovered that while it is possible to uniformly disperse the gaseous ammonia across the cross-section before contact with the first layer of spray liquid by adding internal components, any type of mechanical component will increase the system pressure of the device, ultimately manifesting as an increase in reaction pressure and a reduction in the yield of the target product. The smaller the droplet size, the larger the contact surface between the droplet and the gaseous ammonia, and the better the absorption effect; conversely, the smaller the droplet size, the worse the ammonia absorption effect. Gases are relatively easy to diffuse. Even if the gaseous ammonia is not completely dispersed and uniform at the first spraying position, resulting in slightly poor extinction efficiency, the gaseous ammonia will continue to diffuse during its ascent and will be captured and absorbed by the spray liquid of the subsequent spraying devices. Therefore, although adding components here meets the purpose of rapid and uniform dispersion of gaseous ammonia, the vertical distance from the first layer of spraying device to the inlet is 800-6000mm, preferably 1000-5000mm, which can meet the efficient reaction of the previous reaction section, the extinction efficiency of this tower, and the absorption efficiency of ammonia, which is more economical for the entire device.

[0120] According to one embodiment of the present invention, in the reaction step, the hydrocarbon feedstock is propylene, the molar ratio of propylene / ammonia / air (as molecular oxygen) is 1:1.1-1.3:1.8-2.0, the reaction temperature is 420-440°C, the reaction pressure (gauge pressure) is 0.03-0.14 MPa, and the catalyst weight hourly space velocity is 0.06-0.15h -1 Alternatively, the hydrocarbon feedstock is isobutylene, the molar ratio of isobutylene / ammonia / air (as molecular oxygen) is 1:1.3-1.6:2.2-2.8, the reaction temperature is 395-420°C, the reaction pressure (gauge pressure) is 0.03-0.14 MPa, and the catalyst weight hourly space velocity is 0.08-0.17 h -1 .

[0121] According to one embodiment of the present invention, depending on the different reaction steps, the composition of the reaction product is generally C 1-4 Nitriles (such as acrylonitrile, etc.) account for about 10-20wt%, C 1-4The oxygen-containing compound (such as acrolein) accounts for approximately 0.1-5% by weight, O₂ accounts for approximately 0.1-5% by weight, ammonia accounts for approximately 0.1-2% by weight, and other impurities are the remainder, calculated relative to the total weight of the reaction product as 100% by weight. After preliminary cooling, the reaction product generally has a temperature of 195-235°C and a pressure of 0.03-0.14 MPaG. According to the present invention, the aforementioned technical effects of the production method of the present invention are particularly excellent for this specific reaction product.

[0122] According to one embodiment of the present invention, in the cooling step, the spraying liquid cools the temperature of the reaction product from 195-235° C. to 81-86° C. In addition, preferably, the spraying liquid reduces the ammonia content of the reaction product to below 150 ppm.

[0123] A specific embodiment of the present invention is described in detail below by way of example with reference to the accompanying drawings.

[0124] For example, as shown in FIG4A , according to the present invention, the reaction gas with a temperature of 225°C and unreacted ammonia enter the ammonia absorption tower 1 from the ammonia-containing gas feed port 8, and the circulating liquid is extracted from the bottom of the tower and sent to the multi-layer spraying device 3a-spraying device 3f via the circulating pump 17. The spraying devices 3a-3f are arranged in sequence from top to bottom in the tower, wherein the spraying devices 3a\3c\3e are on the same side, and the spraying devices 3b\3d\3f are on the opposite side to the spraying devices 3a\3c\3e. The vertical distance between the ammonia-containing gas feed port 8 and the spraying device 3f is 1800 mm; the spraying liquid input pressures of the spraying liquid inlets of the spraying devices 3a\3c\3e are 0.327 MPaG, 0 The spray liquid input pressures at the spray liquid inlets of spray devices 3a, 3c, and 3e are 0.327 MPaG, 0.330 MPaG, and 0.334 MPaG, respectively. Sulfuric acid is added to the circulating pump outlet pipeline from the acid solution port 15. The circulating liquid passes through the spray device 3 and enters from the inlet 18 of the spray device 3. It then flows along the fluid direction through the first spray pipe 19, the second spray pipe 20a (20b), and the third spray pipe 21 to the atomizing nozzle 22. The circulating liquid is sprayed from the nozzle 22 to form an acid mist layer in the ammonia absorption tower, which absorbs the gaseous ammonia from the gas feed port 8. The tail gas is discharged from the ammonia absorption tower through the gas phase discharge port 9. The tail gas temperature at the top of the tower is 84°C. The projections of the ends of the third spray pipes of spray devices 3a-3f on the tower cross section overlap, as shown in Figure 5.

[0125] For further example, as shown in FIG4B , according to the present invention, reaction gas at a temperature of 225° C. and unreacted ammonia enter the ammonia absorber 1 from the ammonia-containing gas feed port 8. Circulating liquid is extracted from the bottom of the tower and sent to spray devices 3a-3f via a circulating pump 17. Spray devices 3a, 3c, and 3e are on the same side, and spray devices 3b, 3d, and 3f are on the opposite side of the spray devices 3a, 3c, and 3e. Acidic liquid is added to the circulating pump outlet pipeline from the acid solution port 15. The circulating liquid passes through the spray device 3 and enters from the inlet 18 of the spray device 3. It flows along the fluid direction through the first spray pipe 19, the second spray pipe 20a (20b), and the third spray pipe 21 to the atomizing nozzle 22. The atomizing nozzle rotates leftward and rightward at a ratio of 1:1. The circulating liquid is sprayed from the nozzle 22 to form an acid mist layer in the ammonia absorber, which absorbs the gaseous ammonia from the gas feed port 8. The tail gas is discharged from the ammonia absorber via the gas phase discharge port 9. The tail gas temperature at the top of the tower is 84°C. The projections of the ends of the third spray pipes of the spraying devices 3a-3f on the cross section of the tower overlap, as shown in Figure 6A. The schematic diagram of the nozzle structure of the spraying device and the top view of the spraying device are shown in Figures 11C and 11B.

[0126] Example

[0127] The present invention is further described in detail below with reference to examples, but the present invention is not limited to these examples.

[0128] In the following examples and comparative examples, the residual ammonia concentration in the tail gas can be measured by offline analysis. Specifically, a certain volume (V) of gas is collected from the top of the ammonia absorber. The gas is absorbed by a certain amount of water. The ammonia content in the water is analyzed and converted to the volume of gaseous ammonia (v). The residual ammonia concentration in the tail gas is calculated as v / V. In addition, acid consumption is measured by an acid meter entering the ammonia absorber.

[0129] Example 1

[0130] The ammonia absorption tower adopts the two-stage structure of Figure 3b. The inner diameter of the absorption tower is 7200 mm. No gas distributor 23 is provided in the tower. The linear velocity of the reaction gas in the tower is 1.1 m / s. The acid added to the circulating liquid is sulfuric acid. The acid-containing circulating liquid is delivered to the absorption tower through the upper circulation pump through four spraying devices. The fluid directions in the first spraying pipes of the spraying devices 3a and 3c and 3b and 3d are opposite, that is, the projected angle between the two adjacent spraying liquid inlets is 180°. The spraying devices are shown in Figure 11B from above and in Figure 11C from below. The spray liquid input pressures at the spray liquid inlets of spray devices 3a(b) and 3c(d) are 0.440 MPaG and 0.446 MPaG, respectively, and the spray liquid discharge pressure is 0.051 MPaG. Adjacent spray devices are spaced 1200 mm apart. Each spray device has 16 secondary spray pipes, and each secondary spray pipe is equipped with 11 to 18 tertiary spray pipes. The tertiary spray tip projections of the spray devices overlap and rotate in the same direction. All nozzles on the same side of the secondary spray pipe rotate in the same direction, while nozzles on opposite sides of the secondary spray pipe rotate in opposite directions. Furthermore, the number of nozzles on the opposite sides of two adjacent secondary spray pipes with the same rotation direction is 480 and 480, respectively. The first spray pipe of the spraying device has an inner diameter of 250 mm and a length of 7000 mm. The second spray pipes are spaced 820 mm apart, have an inner diameter of 100 mm, and range in length from 2100 mm to 3450 mm. The third spray pipes are spaced 410 mm apart, have an inner diameter of 40 mm, and are 205 mm long. The spraying device has a total of 960 nozzles, with the ends of two adjacent third spray pipes 580 mm apart, as shown in Figure 6B. The nozzle outlet diameter is 11.5 mm, the nozzle rotation chamber diameter is 40 mm, and the nozzle spray angle is 75°. The vertical distance from the gas feed port 8 to the spraying device 3d is 4000 mm, and the feed port inner diameter is 1300 mm. The reaction product gas entering through the feed port contains approximately 0.71 wt% ammonia, 13.2 wt% acrylonitrile, and the remainder is impurities such as O2, acrolein, and nitrogen. Its temperature is 225°C and its pressure is 0.06 MPaG. Each nozzle discharges 4.8 t / h of spray liquid, and the weight ratio of spray liquid to reaction product gas entering through the gas inlet is 20. Initially, the residual ammonia concentration in the tail gas from the reactor outlet was 41 ppm. After 24 months of operation, the residual ammonia concentration in the tail gas from the reactor outlet was 52 ppm. The acid consumption for 24 months of operation / 1 month of operation was 1.02.

[0131] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.011 m -1 , average droplet diameter D 32is 1130 microns, and the droplet size distribution is D 10 625 μm, D 50 1328 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0021 m -1 , average droplet diameter D 32 is 462 microns, and the droplet size distribution is D 10 406 μm, D 50 593 μm, D 90 It is 894 microns.

[0132] Example 2

[0133] The ammonia absorption tower adopts the one-stage structure shown in Figure 4B . The absorption tower has an inner diameter of 7200 mm and is not equipped with a gas distributor 23. The linear velocity of the reaction gas within the tower is 1.1 m / s. Sulfuric acid is added to the circulating liquid, and the acid-containing circulating liquid is delivered to the absorption tower via a circulation pump through six spraying devices. The flow directions in the first spray pipes of spraying devices 3a, 3c, and 3e are opposite to those in the first spray pipes of 3b, 3d, and 3f, meaning that the angle between the projected spray inlets of two adjacent spraying devices is 180°. A top view of the spraying devices is shown in Figure 11B , and a detailed top view of the spraying devices is shown in Figure 11C . The spray liquid input pressures at the spray liquid inlets of spray devices 3a(b), 3c(d), and 3e(f) were 0.425 MPaG, 0.430 MPaG, and 0.435 MPaG, respectively, and the spray liquid discharge pressures were 0.055 MPaG. The vertical spacing between two adjacent spray devices was 880 mm. Each spray device had 14 secondary spray pipes, and each secondary spray pipe was equipped with 6 to 14 tertiary spray pipes. The tertiary spray tip projections of the spray devices overlapped and rotated in the same direction. All nozzles on the same side of the second spray pipe rotated in the same direction, while nozzles on opposite sides of the second spray pipe rotated in opposite directions. The number of nozzles on the opposite sides of two adjacent second spray pipes with all nozzles rotating in opposite directions and with the same rotation direction was 456 and 456, respectively. The first spray pipe of the spraying device has an inner diameter of 200 mm and a length of 7000 mm. The second spray pipes are spaced 1000 mm apart, have an inner diameter of 100 mm, and range in length from 1850 mm to 3450 mm. The third spray pipes are spaced 500 mm apart, have an inner diameter of 40 mm, and are 250 mm long. The projected ends of the third spray pipes overlap, and the distance between the ends of two adjacent third spray pipes is 500 mm, as shown in Figure 6A. The spraying device has a total of 912 nozzles, with an outlet diameter of 11.7 mm, a nozzle rotation chamber diameter of 36 mm, and a spray angle of 80°. The vertical distance from the gas feed port 8 to the spraying device 3f is 1500 mm, and the vertical distance from the gas feed port 8 to the spraying device 3d is 4000 mm. The feed port has an inner diameter of 1200 mm. The reaction product gas entering through the feed port contains approximately 0.71 wt% ammonia, 13.2 wt% acrylonitrile, and the remainder is impurities such as O2, acrolein, and nitrogen. Its temperature is 225°C and its pressure is 0.06 MPaG. Each nozzle discharges 5.1 t / h of spray liquid, and the weight ratio of spray liquid to reaction product gas entering through the gas inlet is 20. Initially, the residual ammonia concentration in the tail gas from the reactor outlet was 27 ppm. After 24 months of operation, the residual ammonia concentration in the tail gas from the reactor outlet was 34 ppm. The acid consumption for 24 months of operation is 1.01 times the acid consumption for one month of operation.

[0134] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0128 m -1 , average droplet diameter D 32 is 1054 microns, and the droplet size distribution is D 10 832 μm, D 50 1242 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0019 m -1 , average droplet diameter D 32 is 412 microns, and the droplet size distribution is D 10 386 μm, D 50 574 μm, D 90 It is 878 microns.

[0135] Example 3

[0136] The same as Example 2, the only difference is that the spray liquid input pressures at the spray liquid inlets of the spray devices 3a (b), 3c (d) and 3e (f) are 0.152 MPaG, 0.160 MPaG, and 0.168 MPaG, respectively, and the spray liquid discharge pressures are 0.04 MPaG, respectively. The nozzle outlet diameter of the spray device is 11.9 mm. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 72 ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 98 ppm.

[0137] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0058 m -1 , average droplet diameter D 32 is 2226 microns, and the droplet size distribution is D 10 1298 μm, D 50 2384 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0013 m -1 , average droplet diameter D 32 is 542 microns, and the droplet size distribution is D 10 427 μm, D 50 671 μm, D 90 It is 914 microns.

[0138] Example 4

[0139] The same as Example 2, the only difference is that the spray liquid input pressures at the spray liquid inlets of the spray devices 3a (b), 3c (d) and 3e (f) are 0.838 MPaG, 0.844 MPaG, and 0.85 MPaG, respectively, and the spray liquid discharge pressures are 0.42 MPaG, respectively. The nozzle outlet diameter of the spray device is 12.1 mm. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 84 ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 92 ppm.

[0140] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.018 m -1 , average droplet diameter D 32 is 726 microns, and the droplet size distribution is D 10 422 μm, D 50 989 microns, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0035 μm. -1 , average droplet diameter D 32 is 321 microns, and the droplet size distribution is D 10 267 μm, D 50 389 μm, D 90 It is 543 microns.

[0141] Example 5

[0142] The same as Example 2, the only difference is that the spray liquid input pressures at the spray liquid inlets of the spray devices 3a (b), 3c (d) and 3e (f) are 0.950 MPaG, 0.954 MPaG, and 0.959 MPaG, respectively, and the spray liquid discharge pressures are 0.42 MPaG, respectively. The nozzle outlet diameter of the spray device is 11.1 mm. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 105 ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 116 ppm.

[0143] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.01925 m -1 , average droplet diameter D 32 is 432 microns, and the droplet size distribution is D 10 392 μm, D 50 750 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0038 μm. -1 , average droplet diameter D32 is 280 microns, and the droplet size distribution is D 10 159 μm, D 50 345 μm, D 90 It is 511 microns.

[0144] Example 6

[0145] The same as Example 2, the only difference is that the spray liquid input pressures at the spray liquid inlets of the spray devices 3a (b), 3c (d) and 3e (f) are 0.098 MPaG, 0.103 MPaG, and 0.108 MPaG, respectively, and the spray liquid discharge pressures are 0.04 MPaG, respectively. The nozzle outlet diameter of the spray device is 12.3 mm. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 132 ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 181 ppm.

[0146] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0042 m -1 , average droplet diameter D 32 is 2426 microns, and the droplet size distribution is D 10 1398 μm, D 50 2434 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0012 m -1 , average droplet diameter D 32 is 692 microns, and the droplet size distribution is D 10 547 μm, D 50 682 μm, D 90 950 microns.

[0147] Example 7

[0148] The same method as in Example 2 differed in that the vertical spacing between two adjacent spraying devices was 1200 mm, and the distance between the ends of two adjacent third spraying pipes, as shown in FIG6B , was 707 mm. The nozzle outlet diameter of the spraying device was 11.8 mm, and the spray liquid discharge rate of each nozzle was 5.8 t / h. Initially, the residual ammonia concentration in the tail gas from the reactor outlet was 68 ppm. After 24 months of operation, the residual ammonia concentration in the tail gas from the reactor outlet was 96 ppm.

[0149] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.005 m -1 , average droplet diameter D 32 is 1623 microns, and the droplet size distribution is D10 1189 μm, D 50 2148 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0021 m -1 , average droplet diameter D 32 is 432 microns, and the droplet size distribution is D 10 387 μm, D 50 601 μm, D 90 It is 914 microns.

[0150] Example 8

[0151] The same as Example 2, except that the vertical spacing between two adjacent spraying devices is 1200 mm, each spraying device has 18 second spraying pipes, and the second spraying pipes are equipped with 7 to 20 third spraying pipes. The spacing between the second spraying pipes of the spraying device is 670 mm, the inner diameter of the second spraying pipe is 80 mm, and the distance between the ends of two adjacent third spraying pipes is 335 mm as shown in Figure 6A. The spraying device has a total of 2000 nozzles, the nozzle outlet diameter of the spraying device is 11.3 mm, the nozzle rotation chamber diameter is 30 mm, the spray angle is 65°, and the spray liquid discharge rate of each nozzle is 2.64 t / h. In the initial operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet was 86 ppm. After 24 months of operation, the residual ammonia concentration in the tail gas from the reaction outlet was 105 ppm.

[0152] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0078 m -1 , average droplet diameter D 32 is 1814 microns, and the droplet size distribution is D 10 1075 μm, D 50 2184 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0015 μm. -1 , average droplet diameter D 32 is 460 microns, and the droplet size distribution is D 10 437 μm, D 50 651 μm, D 90 It is 893 microns.

[0153] Example 9

[0154] The same method as in Example 2 differed in that the spray liquid input pressures at the spray liquid inlets of spray devices 3a(b), 3c(d), and 3e(f) were 0.376 MPaG, 0.380 MPaG, and 0.385 MPaG, respectively; the spray liquid discharge pressures were 0.045 MPaG, respectively; the vertical spacing between two adjacent spray devices was 550 mm, and the distance between the ends of two adjacent third spray pipes, as shown in Figure 6B, was 707 mm. Initially, the residual ammonia concentration in the tail gas from the reactor outlet was 120 ppm. After 24 months of operation, the residual ammonia concentration in the tail gas from the reactor outlet was 162 ppm.

[0155] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0042 m -1 , average droplet diameter D 32 is 2154 microns, and the droplet size distribution is D 10 1096 microns, D 50 2628 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0011 m -1 , average droplet diameter D 32 is 367 microns, and the droplet size distribution is D 10 316 microns, D 50 484 μm, D 90 It is 616 microns.

[0156] Example 10

[0157] The same as Example 2, except that the vertical spacing between two adjacent spraying devices is 1200 mm, each spraying device has 24 second spraying pipes, and the second spraying pipes are equipped with 9 to 24 third spraying pipes. The spacing between the second spraying pipes of the spraying device is 580 mm, the inner diameter of the second spraying pipe is 80 mm, and the distance between the ends of two adjacent third spraying pipes as shown in Figure 6A is 290 mm. The spraying device has a total of 2640 nozzles, the nozzle outlet diameter of the spraying device is 9.1 mm, the nozzle rotation chamber diameter is 30 mm, the spray angle is 65°, and the spray liquid discharge rate of each nozzle is 2.0 t / h. In the initial operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet was 146 ppm. After 24 months of operation, the residual ammonia concentration in the tail gas from the reaction outlet was 185 ppm.

[0158] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0059 m -1 , average droplet diameter D 32 is 1934 microns, and the droplet size distribution is D 101738 μm, D 50 2128 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0013 m -1 , average droplet diameter D 32 is 347 microns, and the droplet size distribution is D 10 284 μm, D 50 482 μm, D 90 It is 615 microns.

[0159] Example 11

[0160] The same as Example 2, except that the spray liquid discharge rate of each nozzle is 8.5t / h, and the weight ratio of the spray liquid to the reaction product gas entering from the gas inlet is 32; after the device has been in operation for 1 month, the residual ammonia concentration in the tail gas at the reaction outlet is 85ppm, and after the device has been in operation for 24 months, the residual ammonia concentration in the tail gas at the reaction outlet is 99ppm, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.03.

[0161] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0016 m -1 , average droplet diameter D 32 is 1712 microns, and the droplet size distribution is D 10 1138 μm, D 50 2324 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0014 μm. -1 , average droplet diameter D 32 is 787 microns, and the droplet size distribution is D 10 556 μm, D 50 832 μm, D 90 It is 1042 microns.

[0162] Example 12

[0163] The same as Example 2, except that the spray liquid discharge rate of each nozzle is 1.5 t / h, and the weight ratio of the spray liquid to the reaction product gas entering from the gas inlet is 11; after the device has been in operation for 1 month, the residual ammonia concentration in the tail gas at the reaction outlet is 145 ppm, and after the device has been in operation for 24 months, the residual ammonia concentration in the tail gas at the reaction outlet is 178 ppm, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.05.

[0164] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.005 m -1 , average droplet diameter D 32 is 469 microns, and the droplet size distribution is D 10 409 μm, D 50 772 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0012 m -1 , average droplet diameter D 32 is 348 microns, and the droplet size distribution is D 10 159 μm, D 50 393 μm, D 90 It is 604 microns.

[0165] Example 13

[0166] The same as Example 2, the only difference is that the inlets of the spraying devices 3a-3f are arranged at different positions of the equipment, the projections of the first spraying pipes of the spraying devices 3a-3f on the cross section overlap, and the projections of the second spraying pipe, the third spraying pipe and the nozzle on the cross section do not overlap. After the device has been in operation for 1 month, the residual ammonia concentration of the exhaust gas at the reaction outlet is 137 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the exhaust gas at the reaction outlet is 148 ppm.

[0167] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0063 m -1 , average droplet diameter D 32 is 1852 microns, and the droplet size distribution is D 10 1593 μm, D 50 1882 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.001 m -1 , average droplet diameter D 32 is 430 microns, and the droplet size distribution is D 10 392 μm, D 50 575 μm, D 90 It is 783 microns.

[0168] Example 14

[0169] The same as Example 2, except that the nozzle diameter on the 1st to 11th second spray pipes of the first spray pipe along the fluid direction is 36 mm, and the nozzle diameter on the 12th to 14th second spray pipes of the first spray pipe is 32 mm; after the device has been in operation for 1 month, the residual ammonia concentration in the exhaust gas at the reaction outlet is 63 ppm, and after the device has been in operation for 24 months, the residual ammonia concentration in the exhaust gas at the reaction outlet is 99 ppm.

[0170] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0127 m -1 , average droplet diameter D 32 is 824 microns, and the droplet size distribution is D 10 598 μm, D 50 1198 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0018 m -1 , average droplet diameter D 32 is 411 microns, and the droplet size distribution is D 10 375 μm, D 50 586 μm, D 90 It is 880 microns.

[0171] Example 15

[0172] The same as Example 2, the only difference is that the vertical spacing between two adjacent spraying devices is 1250 mm, the residual ammonia concentration of the tail gas from the reaction outlet is 77 ppm at the initial operation of the device, the residual ammonia concentration of the tail gas from the reaction outlet is 85 ppm after the device has been in operation for 24 months, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.04.

[0173] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0094 m -1 , average droplet diameter D 32 is 1408 microns, and the droplet size distribution is D 10 1009 μm, D 50 2083 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0016 m -1 , average droplet diameter D 32 is 469 microns, and the droplet size distribution is D 10 372 μm, D 50 579 μm, D 90 It is 880 microns.

[0174] Example 16

[0175] The same as Example 2, the only difference is that the vertical spacing between two adjacent spraying devices is 720 mm, the residual ammonia concentration of the tail gas from the reaction outlet is 111 ppm at the initial operation of the device, the residual ammonia concentration of the tail gas from the reaction outlet is 129 ppm after the device has been in operation for 24 months, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.07.

[0176] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0143 m -1 , average droplet diameter D 32 is 935 microns, and the droplet size distribution is D 10 616 μm, D 50 1323 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0015 μm. -1 , average droplet diameter D 32 is 420 microns, and the droplet size distribution is D 10 389 μm, D 50 480 μm, D 90 It is 632 microns.

[0177] Example 17

[0178] The same as Example 2, the only difference is that the vertical spacing between two adjacent spraying devices is 1650 mm, the residual ammonia concentration of the tail gas from the reaction outlet is 177 ppm at the initial operation of the device, the residual ammonia concentration of the tail gas from the reaction outlet is 195 ppm after the device has been in operation for 24 months, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.05.

[0179] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0053 m -1 , average droplet diameter D 32 is 2215 microns, and the droplet size distribution is D 10 1295 μm, D 50 2489 μm, D 90 In addition, when measured at a vertical distance of 10350 mm above the gas inlet (above the spraying device), the extinction coefficient of the absorbing atmosphere is 0.0011 m -1 , average droplet diameter D 32 is 580 microns, and the droplet size distribution is D 10 319 μm, D50 645 μm, D 90 It is 711 microns.

[0180] Example 18

[0181] The same as Example 2, except that the vertical spacing between two adjacent spraying devices is 550 mm, the device is operated for 1 month, the residual ammonia concentration of the reaction outlet exhaust gas is 129 ppm, the device is operated for 24 months, the residual ammonia concentration of the reaction outlet exhaust gas is 145 ppm, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.04.

[0182] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0187 m -1 , average droplet diameter D 32 is 895 microns, and the droplet size distribution is D 10 566 μm, D 50 1129 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0011 m -1 , average droplet diameter D 32 is 350 microns, and the droplet size distribution is D 10 219 μm, D 50 445 μm, D 90 It is 511 microns.

[0183] Example 19

[0184] The same as Example 2, the only difference is that the spray liquid input pressures at the spray liquid inlets of the spray devices 3a (b), 3c (d) and 3e (f) are 0.405 MPaG, 0.421 MPaG, and 0.435 MPaG, respectively. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 65 ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 89 ppm.

[0185] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0135 m -1 , average droplet diameter D 32 is 992 microns, and the droplet size distribution is D 10 735 μm, D 50 1112 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0025 μm. -1 , average droplet diameter D32 is 402 microns, and the droplet size distribution is D 10 366 μm, D 50 580 μm, D 90 It is 808 microns.

[0186] Example 20

[0187] The same as Example 2, the only difference is that the spray liquid input pressures at the spray liquid inlets of the spray devices 3a (b), 3c (d) and 3e (f) are 0.327 MPaG, 0.352 MPaG, and 0.376 MPaG, respectively. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 112 ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 145 ppm.

[0188] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0094 m -1 , average droplet diameter D 32 is 1432 microns, and the droplet size distribution is D 10 1032 μm, D 50 1789 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0012 m -1 , average droplet diameter D 32 is 497 microns, and the droplet size distribution is D 10 452 μm, D 50 620 μm, D 90 It is 913 microns.

[0189] Example 21

[0190] The same as Example 1, the only difference is that the vertical distance from the gas inlet to the spraying device 3f is 6000 mm. At the initial stage of the device operation, the residual ammonia concentration of the tail gas from the reaction outlet is 77 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the tail gas from the reaction outlet is 85 ppm.

[0191] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0093 m -1 , average droplet diameter D 32 is 1132 microns, and the droplet size distribution is D 10 932 μm, D 50 1248 μm, D 90In addition, when measured at a vertical distance of 13500 mm above the gas inlet (above the spraying device), the extinction coefficient of the absorbing atmosphere is 0.0016 m - 1 , average droplet diameter D 32 is 372 microns, and the droplet size distribution is D 10 416 μm, D 50 491 μm, D 90 It is 638 microns.

[0192] Example 22

[0193] The same as Example 2, the only difference is that the vertical distance from the gas inlet to the spraying device 3f is 8000 mm. At the initial stage of the device operation, the residual ammonia concentration of the tail gas from the reaction outlet is 90 ppm. After 24 months of operation, the residual ammonia concentration of the tail gas from the reaction outlet is 106 ppm.

[0194] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0062 m -1 , average droplet diameter D 32 is 1520 microns, and the droplet size distribution is D 10 1249 μm, D 50 1742 μm, D 90 In addition, when measured at a vertical distance of 16000 mm above the gas inlet (above the spraying device), the extinction coefficient of the absorbing atmosphere is 0.0015 m - 1 , average droplet diameter D 32 is 326 microns, and the droplet size distribution is D 10 291 μm, D 50 485 μm, D 90 It is 794 microns.

[0195] However, as the total height of the tower equipment increases, the equipment investment cost increases, and at the same time, the difficulty of maintenance of the device is increased.

[0196] Example 23

[0197] The same as Example 2, the only difference is that the vertical distance from the gas inlet to the spraying device 3f is 900 mm. At the initial stage of the device operation, the residual ammonia concentration of the tail gas from the reaction outlet is 125 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the tail gas from the reaction outlet is 142 ppm.

[0198] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0055 m -1, average droplet diameter D 32 is 1220 microns, and the droplet size distribution is D 10 749 μm, D 50 1468 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0016 m -1 , average droplet diameter D 32 is 486 microns, and the droplet size distribution is D 10 419 μm, D 50 685 μm, D 90 It is 898 microns.

[0199] Example 24

[0200] The same as Example 2, the only difference is that the vertical distance from the gas inlet to the spraying device 3f is 500 mm. At the initial stage of the device operation, the residual ammonia concentration of the tail gas from the reaction outlet is 182 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the tail gas from the reaction outlet is 219 ppm.

[0201] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0043 m -1 , average droplet diameter D 32 is 1143 microns, and the droplet size distribution is D 10 648 μm, D 50 2163 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0018 μm. -1 , average droplet diameter D 32 is 402 microns, and the droplet size distribution is D 10 284 μm, D 50 575 μm, D 90 It is 969 microns.

[0202] Example 25

[0203] The same as Example 2, the only difference is that a gas distributor 23 is provided in the tower. As shown in FIG4B , the residual ammonia concentration of the tail gas from the reaction outlet is 35 ppm. After the gas distribution internals are added, the pressure of the ammonia absorption tower kettle increases by 10 kPa, resulting in an increase in the reaction pressure of the ammonia absorption tower pre-system by 10 kPa, and the yield of the target product nitrile decreases by 1.5%.

[0204] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0127 m-1 , average droplet diameter D 32 is 1068 microns, and the droplet size distribution is D 10 790 μm, D 50 1222 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.002 m -1 , average droplet diameter D 32 is 398 microns, and the droplet size distribution is D 10 376 μm, D 50 572 μm, D 90 It is 864 microns.

[0205] Example 26

[0206] The process was identical to Example 2, except that the linear velocity of the reaction gas within the tower was 0.6 m / s and the spray rate of each nozzle was 2.8 t / h. The residual ammonia concentration in the tail gas from the reactor outlet was 82 ppm at the initial stage of operation. After 24 months of operation, the residual ammonia concentration in the tail gas from the reactor outlet was 99 ppm.

[0207] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.009 m -1 , average droplet diameter D 32 is 1254 microns, and the droplet size distribution is D 10 895 μm, D 50 1405 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0016 μm. -1 , average droplet diameter D 32 is 486 microns, and the droplet size distribution is D 10 385 μm, D 50 568 μm, D 90 It is 880 microns.

[0208] Example 27

[0209] The same as Example 2, the only difference is that the linear velocity of the reaction gas in the tower is 1.4 m / s, the spray liquid discharge of each nozzle is 5.1 t / h, the weight ratio of the spray liquid to the reaction product gas entering from the gas inlet is 17, and the residual ammonia concentration of the tail gas from the reaction outlet at the initial operation of the device is 132 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the tail gas from the reaction outlet is 154 ppm.

[0210] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0191 m -1 , average droplet diameter D 32 is 954 microns, and the droplet size distribution is D 10 595 μm, D 50 1389 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0029 m -1 , average droplet diameter D 32 is 390 microns, and the droplet size distribution is D 10 336 μm, D 50 564 μm, D 90 It is 882 microns.

[0211] Example 28

[0212] The process was identical to Example 2, except that the linear velocity of the reaction gas within the tower was 0.4 m / s and the spray rate of each nozzle was 2.0 t / h. The residual ammonia concentration in the tail gas from the reactor outlet was 173 ppm at the initial stage of operation. After 24 months of operation, the residual ammonia concentration in the tail gas from the reactor outlet was 195 ppm.

[0213] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.006 m -1 , average droplet diameter D 32 is 1350 microns, and the droplet size distribution is D 10 985 μm, D 50 1549 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.001 m -1 , average droplet diameter D 32 is 416 microns, and the droplet size distribution is D 10 385 μm, D 50 581 μm, D 90 It is 872 microns.

[0214] Example 29

[0215] The same as Example 2, the only difference is that the linear velocity of the reaction gas in the tower is 1.9 m / s, the spray liquid discharge of each nozzle is 6.2 t / h, the weight ratio of the spray liquid to the reaction product gas entering from the gas inlet is 15, and the residual ammonia concentration of the tail gas from the reaction outlet at the initial operation of the device is 182 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the tail gas from the reaction outlet is 199 ppm.

[0216] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.02 m -1 , average droplet diameter D 32 is 890 microns, and the droplet size distribution is D 10 522 μm, D 50 1234 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0039 m -1 , average droplet diameter D 32 is 361 microns, and the droplet size distribution is D 10 306 microns, D 50 514 μm, D 90 It is 847 microns.

[0217] Example 30

[0218] The ammonia absorption tower was identical to Example 2, except that it employed the one-stage structure shown in FIG4A . The flow directions within the first spray pipes of spray devices 3a, 3b, and 3c were opposite to those of spray devices 3d, 3e, and 3f. This meant that the projections of the spray inlets of the upper three layers of spray devices 3a, 3b, and 3c substantially overlapped, as did the projections of the spray inlets of the lower three layers of spray devices 3d, 3e, and 3f. Furthermore, the angle between the projections of the spray inlets of the upper and lower three layers was 180°. After one month of operation, the residual ammonia concentration in the exhaust gas from the reaction outlet was 42 ppm. After 24 months of operation, the residual ammonia concentration in the exhaust gas from the reaction outlet was 61 ppm. The acid consumption for 24 months of operation was divided by the acid consumption for one month of operation by 1.03.

[0219] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0118 m -1 , average droplet diameter D 32 is 934 microns, and the droplet size distribution is D 10 698 μm, D 50 1367 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0019 m -1, average droplet diameter D 32 is 417 microns, and the droplet size distribution is D 10 392 μm, D 50 584 μm, D 90 It is 898 microns.

[0220] Example 31

[0221] The same as Example 2, the only difference is that the projections of the first spray pipes of the spray devices 3a, 3c, 3e and 3b, 3d, 3f on the cross section overlap, while the projections of the second spray pipe, the third spray pipe and the nozzle on the cross section do not overlap. As shown in Figure 7, after the device has been in operation for 1 month, the residual ammonia concentration of the reaction outlet exhaust gas is 78ppm, and after the device has been in operation for 24 months, the residual ammonia concentration of the reaction outlet exhaust gas is 95ppm. The acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.05.

[0222] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0103 m -1 , average droplet diameter D 32 is 1146 microns, and the droplet size distribution is D 10 790 μm, D 50 1742 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.002 m -1 , average droplet diameter D 32 is 442 microns, and the droplet size distribution is D 10 401 μm, D 50 612 μm, D 90 It is 934 microns.

[0223] Example 32

[0224] The same as Example 2, except that the nozzle rotation chambers on opposite sides of the eight second spray pipes on each spray device were oriented in opposite directions, while the nozzle rotation chambers on opposite sides of the other eight second spray pipes were oriented in the same direction. After the device operated for one month, the residual ammonia concentration in the exhaust gas at the reaction outlet was 90 ppm. After the device operated for 24 months, the residual ammonia concentration in the exhaust gas at the reaction outlet was 105 ppm. The acid consumption for the 24-month operation of the device / the acid consumption for the one-month operation of the device was 1.04.

[0225] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0103 m -1 , average droplet diameter D 32 is 1231 microns, and the droplet size distribution is D 10778 μm, D 50 1692 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0018 m -1 , average droplet diameter D 32 is 449 microns, and the droplet size distribution is D 10 420 μm, D 50 643 μm, D 90 It is 946 microns.

[0226] Example 33

[0227] The same as Example 2, the only difference is that the projections of the third spraying ends of the spraying devices overlap and the rotation directions of the nozzles of adjacent spraying devices with overlapping projections are opposite. After the device has been in operation for 1 month, the residual ammonia concentration of the exhaust gas at the reaction outlet is 85 ppm. After the device has been in operation for 24 months, the residual ammonia concentration of the exhaust gas at the reaction outlet is 110 ppm. The acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.05.

[0228] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0100 m -1 , average droplet diameter D 32 is 1327 microns, and the droplet size distribution is D 10 808 μm, D 50 1700 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0018 m -1 , average droplet diameter D 32 is 452 microns, and the droplet size distribution is D 10 424 μm, D 50 656 μm, D 90 It is 989 microns.

[0229] Example 34

[0230] The same as Example 2, except that the two adjacent nozzles on one side of the second spray pipe of the spray device rotate in opposite directions, while all nozzles on the same horizontal parallel extension line of the second spray pipe rotate in the same direction. A top view of the spray device is shown in Figure 11B, and a detailed top view of the spray device is shown in the schematic diagram of Figure 11E. After one month of operation, the residual ammonia concentration in the reaction outlet exhaust gas was 106 ppm. After 24 months of operation, the residual ammonia concentration in the reaction outlet exhaust gas was 125 ppm. The acid consumption of the device in 24 months of operation / the acid consumption of the device in one month of operation was 1.05.

[0231] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0074 m -1 , average droplet diameter D 32 is 1291 microns, and the droplet size distribution is D 10 728 μm, D 50 1702 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.00145 μm. -1 , average droplet diameter D 32 is 519 microns, and the droplet size distribution is D 10 436 μm, D 50 672 μm, D 90 It is 1046 microns.

[0232] Example 35

[0233] The same as in Example 2, except that all nozzles on opposite sides of two adjacent second spray pipes of the spraying device sprayed liquid in the same direction of rotation, while the nozzles on both sides of the same second spray pipe sprayed liquid in opposite directions of rotation. After the device operated for one month, the residual ammonia concentration in the exhaust gas at the reaction outlet was 108 ppm. After the device operated for 24 months, the residual ammonia concentration in the exhaust gas at the reaction outlet was 121 ppm. The acid consumption of the device in 24 months of operation / the acid consumption of the device in one month of operation was 1.04.

[0234] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0072 m -1 , average droplet diameter D 32 is 1345 microns, and the droplet size distribution is D 10 723 μm, D 50 1726 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.00143 m -1 , average droplet diameter D 32 is 503 microns, and the droplet size distribution is D 10 438 μm, D 50 699 μm, D 90 It is 1167 microns.

[0235] Example 36

[0236] The same as Example 2, except that the two adjacent nozzles on one side of the second spray pipe of the spray device rotated in opposite directions, and the nozzles on opposite sides of the same second spray pipe rotated in opposite directions. After the device operated for one month, the residual ammonia concentration in the exhaust gas at the reaction outlet was 125 ppm. After the device operated for 24 months, the residual ammonia concentration in the exhaust gas at the reaction outlet was 148 ppm. The acid consumption for 24 months of operation / one month of operation was 1.05.

[0237] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0064 m -1 , average droplet diameter D 32 is 1446 microns, and the droplet size distribution is D 10 723 μm, D 50 1825 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.00141 m -1 , average droplet diameter D 32 is 513 microns, and the droplet size distribution is D 10 420 μm, D 50 739 μm, D 90 It is 1190 microns.

[0238] Example 37

[0239] The same as Example 1, except that the rotation chamber directions of all nozzles of the spraying device are all the same, the device is operated for 1 month, the residual ammonia concentration of the tail gas from the reaction outlet is 129 ppm, the device is operated for 24 months, the residual ammonia concentration of the tail gas from the reaction outlet is 149 ppm, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.06.

[0240] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0052 m -1 , average droplet diameter D 32 is 1586 microns, and the droplet size distribution is D 10 723 μm, D 50 1825 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0012 m -1 , average droplet diameter D 32 is 545 microns, and the droplet size distribution is D 10 430 μm, D 50 780 μm, D 90It is 1254 microns.

[0241] Example 38

[0242] The same as Example 2, except that the distance between adjacent third spray pipes is 300 mm, and the distance between the ends of two adjacent third spray pipes (as shown in Figure 6A) is 300 mm. The residual ammonia concentration in the tail gas at the reactor outlet is 76 ppm.

[0243] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0051 m -1 , average droplet diameter D 32 is 1620 microns, and the droplet size distribution is D 10 1182 μm, D 50 2145 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0022 m -1 , average droplet diameter D 32 is 430 microns, and the droplet size distribution is D 10 382 μm, D 50 604 μm, D 90 It is 924 microns.

[0244] Example 39

[0245] The same as Example 2, except that the distance between the ends of two adjacent third spray pipes is 340 mm as shown in FIG6A . The residual ammonia concentration of the tail gas at the reaction outlet is 105 ppm.

[0246] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0079 m -1 , average droplet diameter D 32 is 1821 microns, and the droplet size distribution is D 10 1077 μm, D 50 2180 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.00156 m -1 , average droplet diameter D 32 is 461 microns, and the droplet size distribution is D 10 427 μm, D 50 654 μm, D 90 It is 883 microns.

[0247] Example 40

[0248] The same as Example 2, except that the nozzle outlet diameter on the 1st to 11th second spray pipes of the first spray pipe along the fluid direction is 11.7 mm, and the nozzle outlet diameter on the 12th to 14th second spray pipes of the first spray pipe is 11.9 mm; after the device has been in operation for 1 month, the residual ammonia concentration in the tail gas at the reaction outlet is 85 ppm, and after the device has been in operation for 24 months, the residual ammonia concentration in the tail gas at the reaction outlet is 99 ppm, and the acid consumption of the device in 24 months of operation / the acid consumption of the device in 1 month of operation is 1.03.

[0249] In this embodiment, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.00161 m -1 , average droplet diameter D 32 is 1722 microns, and the droplet size distribution is D 10 1128 μm, D 50 2310 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0014 m -1 , average droplet diameter D 32 is 777 microns, and the droplet size distribution is D 10 536 μm, D 50 841 μm, D 90 998 microns.

[0250] Comparative Example 1

[0251] The same as Example 1, except that the ammonia absorption tower adopts the two-stage structure of Figure 1, the spray liquid input pressures of the spray liquid inlets of the spray devices 3a, 3b, 3c, and 3d are 0.04MPaG, 0.044MPaG, 0.046MPaG, and 0.051MPaG, respectively, the spray liquid discharge pressure is 0.02MPaG, the nozzle outlet diameter is 14.2mm, and at the initial stage of the device operation, the residual ammonia concentration in the tail gas from the reaction outlet is 400ppm. After the device has been in operation for 24 months, the residual ammonia concentration in the tail gas from the reaction outlet is 529ppm.

[0252] In this comparative example, the extinction coefficient of the absorbing atmosphere is 0.0033 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 , average droplet diameter D 32 is 2976 microns, and the droplet size distribution is D 10 1298 μm, D 50 3174 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0008 m -1, average droplet diameter D 32 is 742 microns, and the droplet size distribution is D 10 523 μm, D 50 882 μm, D 90 is 1050 microns.

[0253] Comparative Example 2

[0254] The same as Example 2, except that the ammonia absorber adopts the one-stage structure of Figure 2, spraying devices 3a, 3b, 3c, 3d, 3e and 3f, the spray liquid input pressures at the spray liquid inlet are 1.202MPaG, 1.205MPaG, 1.209MPaG, 1.214MPaG, 1.217MPaG, and 1.220MPaG, respectively, and the spray liquid discharge pressure is 0.076MPaG. At the initial stage of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 85ppm. After 24 months of operation of the device, the residual ammonia concentration in the tail gas from the reaction outlet is 96ppm. However, 1.5% ammonium sulfate was detected in the tail gas condensate at the outlet of the ammonia absorber.

[0255] In this comparative example, when measured at a vertical distance of 3000 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0263 m -1 , average droplet diameter D 32 is 369 microns, and the droplet size distribution is D 10 232 μm, D 50 550 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0052 m -1 , average droplet diameter D 32 is 231 microns, and the droplet size distribution is D 10 149 μm, D 50 315 μm, D 90 It is 436 microns.

[0256] Comparative Example 3

[0257] The same as Example 1, the only difference is that the spray inlets 18 of spray devices 3a, 3c and 3b, 3d are on the same side of the ammonia absorber, that is, the flow direction in the first spray pipe is the same, the spray inlet projections of spray devices 3a, 3b, 3c and 3d basically overlap, (as shown in Figure 1), and the cross-sectional projections of the nozzles at the end of the third spray pipes of spray devices 3a, 3c and 3b, 3d overlap (as shown in Figure 5). After the device operated for one month, the residual ammonia concentration in the reaction outlet exhaust gas was 85 ppm. After the device operated for 24 months, the residual ammonia concentration in the reaction outlet exhaust gas was 253 ppm. The acid consumption of the device in 24 months of operation / the acid consumption of the device in one month of operation was 1.13.

[0258] In this comparative example, the extinction coefficient of the absorbing atmosphere is 0.0038 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 , average droplet diameter D 32 is 1386 microns, and the droplet size distribution is D 10 523 μm, D 50 1725 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0008 μm. -1 , average droplet diameter D 32 is 545 microns, and the droplet size distribution is D 10 130 μm, D 50 680 μm, D 90 It is 1454 microns.

[0259] Comparative Example 4

[0260] The same as Example 2, the only difference is that the spray inlets 18 of spray devices 3a, 3c, 3e and 3b, 3d, 3f are on the same side of the ammonia absorber, that is, the flow direction in the first spray pipe is the same, the spray inlet projections of spray devices 3a, 3b, 3c, 3d, 3e, 3f basically overlap, (as shown in Figure 2), and the cross-sectional projections of the nozzles at the end of the third spray pipes of spray devices 3a, 3c and 3b, 3d overlap (as shown in Figure 5). After the device was operated for one month, the residual ammonia concentration in the reaction outlet exhaust gas was 73ppm. After the device was operated for 24 months, the residual ammonia concentration in the reaction outlet exhaust gas was 223ppm. The acid consumption of the device in 24 months of operation / the acid consumption of the device in one month of operation was 1.13.

[0261] In this comparative example, the extinction coefficient of the absorbing atmosphere is 0.0039 m / s when measured at a vertical distance of 3000 mm above the gas inlet. -1 , average droplet diameter D 32 is 1356 microns, and the droplet size distribution is D 10 521 μm, D 50 1856 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0008 μm. -1 , average droplet diameter D 32 is 536 microns, and the droplet size distribution is D 10 137 μm, D 50 649 μm, D 90 It is 1450 microns.

[0262] Comparative Example 5

[0263] This is the same as Example 2, differing only in that the spray inlets 18 of spray devices 3a, 3c, and 3e, and 3b, 3d, and 3f, project at a 30° angle on the cross section. That is, the flow directions of the corresponding first spray pipes of the spray devices are oriented at a 30° angle, and the projections of the ends of the third spray pipes of the spray devices do not overlap, as shown in FIG8B . After one month of operation, the residual ammonia concentration in the exhaust gas at the reaction outlet was 130 ppm. After 24 months of operation, the residual ammonia concentration in the exhaust gas at the reaction outlet was 343 ppm. The acid consumption for 24 months of operation / one month of operation was 1.15.

[0264] In this comparative example, the extinction coefficient of the absorbing atmosphere is 0.0034 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 , average droplet diameter D 32 is 1672 microns, and the droplet size distribution is D 10 540 μm, D 50 1738 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0008 m -1 , average droplet diameter D 32 is 436 microns, and the droplet size distribution is D 10 189 μm, D 50 649 μm, D 90 It is 1550 microns.

[0265] Comparative Example 6

[0266] This is the same as Example 2, except that the spray inlets 18 of spray devices 3a, 3c, and 3e, and 3b, 3d, and 3f, project at a 90° angle on the cross section. That is, the flow directions of the corresponding first spray pipes of the spray devices are 90°, and the projections of the ends of the third spray pipes of the spray devices do not overlap. After one month of operation, the residual ammonia concentration in the exhaust gas at the reaction outlet was 110 ppm. After 24 months of operation, the residual ammonia concentration in the exhaust gas at the reaction outlet was 293 ppm. The acid consumption for 24 months of operation / one month of operation was 1.10.

[0267] In this comparative example, the extinction coefficient of the absorbing atmosphere is 0.0035 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 , average droplet diameter D 32 is 1582 microns, and the droplet size distribution is D 10 640 μm, D 50 1714 μm, D 90In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0009 m -1 , average droplet diameter D 32 is 461 microns, and the droplet size distribution is D 10 259 μm, D 50 618 μm, D 90 It is 1489 microns.

[0268] Comparative Example 7

[0269] This is the same as Example 2, differing only in that the spray inlets 18 of spray devices 3a, 3c, and 3e, and 3b, 3d, and 3f, project at a 120° angle on the cross-section. This means that the flow directions of the corresponding first spray pipes of the spray devices are 90°, and the projections of the ends of the third spray pipes of the spray devices do not overlap, as shown in Figure 8B. After one month of operation, the residual ammonia concentration in the exhaust gas at the reaction outlet was 132 ppm. After 24 months of operation, the residual ammonia concentration in the exhaust gas at the reaction outlet was 353 ppm. The acid consumption for 24 months of operation / one month of operation was 1.15.

[0270] In this comparative example, the extinction coefficient of the absorbing atmosphere is 0.0032 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 , average droplet diameter D 32 is 2522 microns, and the droplet size distribution is D 10 678 μm, D 50 2924 μm, D 90 In addition, when measured at a vertical distance of 8500 mm above the gas inlet, the extinction coefficient of the absorbing atmosphere is 0.0006 m -1 , average droplet diameter D 32 is 491 microns, and the droplet size distribution is D 10 259 μm, D 50 876 μm, D 90 It is 1573 microns.

Claims

1. A method for producing a nitrile, comprising the steps of causing a hydrocarbon feedstock to undergo an ammoxidation reaction to produce a reaction product containing a nitrile (referred to as a reaction step), and introducing the reaction product into an absorber through a gas inlet and spraying a spray liquid on the reaction product in the absorber through a spray device to cool the reaction product and form an absorption atmosphere (referred to as a cooling step), wherein the extinction coefficient of the absorption atmosphere is 0.004-0.02 m when measured at a vertical distance of 3000 mm above the gas inlet. -1 (Preferably 0.006-0.018m -1 ).

2. The manufacturing method according to claim 1, wherein the average diameter D of the droplets of the absorption atmosphere when measured at a vertical distance of 3000 mm above the gas inlet is 32 400-2600 microns (preferably 600-2400 microns), and / or, when measured at a vertical distance of 3000 mm above the gas inlet, the droplet size distribution of the absorption atmosphere is D 10 150-1500 microns, D 50 700-3000 microns, D 90 1400-3600 microns (preferably D 10 250-1400 microns, D 50 800-2800 μm, D 90 is 1600-3500 microns).

3. The manufacturing method according to claim 1, wherein the extinction coefficient of the absorbing atmosphere is 0.001-0.004 m / s when measured at a vertical distance of 8500 mm above the gas inlet. -1 (Preferably 0.0015-0.0035m -1 ), and / or, when measured at a vertical distance of 8500 mm above the gas inlet, the average diameter D of the droplets of the absorption atmosphere 32 200-1400 microns (preferably 400-1000 microns), and / or, when measured at a vertical distance of 8500 mm above the gas inlet, the droplet size distribution of the absorption atmosphere is D 10 100-1000 microns, D 50 300-1800 μm, D 90 500-2200 microns (preferably D 10 200-600 microns, D 50 400-1400 μm, D 90 is 600-1800 microns).

4. The manufacturing method according to claim 1, wherein the spraying device comprises a spray liquid inlet, a first spray pipe fluidically connected to the spray liquid inlet, a plurality of second spray pipes fluidically connected to the first spray pipe and extending perpendicularly to the first spray pipe to both sides thereof, a plurality of third spray pipes fluidically connected to the second spray pipe and extending perpendicularly to the second spray pipe to both sides thereof, and a nozzle located at the end of the third spray pipe and fluidically connected thereto.

5. The manufacturing method according to claim 4, wherein on two adjacent second spray pipes, the straight-line distance M between the end of any third spray pipe on one second spray pipe and the end of any third spray pipe on another adjacent second spray pipe is not less than 320 mm (preferably not less than 350 mm), and / or, the nozzles are the same or different, and the spraying amount of the spray liquid is independently 0.5-7.5 t / h (preferably 0.9-6.5t / h), and / or, the nozzles are the same or different, and the spray liquid spraying pressure at the nozzle outlet is independently 0.03-0.85MPaG (preferably 0.04-0.65MPaG), and / or, the spray liquid input pressure at the spray liquid inlet is controlled at 0.06-1.00MPaG (preferably 0.12-0.90MPaG, more preferably 0.18-0.80MPaG), and / or, the difference (absolute value) in the spray liquid input pressure of any two spraying devices at the spray liquid inlet is less than 0.024MPa (preferably less than 0.018MPa, more preferably less than 0.012MPa).

6. The manufacturing method according to claim 1, wherein a plurality (e.g., 2-10, preferably 4-8) of the spraying devices are layered inside the absorption device along the central axis direction of the absorption device at a predetermined vertical spacing, and / or the vertical spacing between two adjacent spraying devices (measured by the vertical spacing of the spraying liquid inlets of the spraying devices) is 650-1350 mm (preferably 750-1200 mm).

7. The manufacturing method according to claim 4, wherein when the cross section is obtained by cross-cutting the absorption device in a direction perpendicular to the central axis of the absorption device, the projections of at least one (preferably all) of the first spray pipe, the second spray pipe and the third spray pipe selected from one of the multiple spray devices and another of the multiple spray devices on the cross section substantially coincide.

8. The manufacturing method of claim 7, wherein the projections of all nozzles of the one spraying device and the other spraying device on the cross section substantially overlap, and / or the two nozzles whose projections substantially overlap have the same spray diameter, and / or the two nozzles whose projections substantially overlap have the same spray liquid rotation direction.

9. The manufacturing method according to claim 1, wherein the vertical distance between the gas inlet and the spray liquid inlet of the spraying device (when there are multiple spraying devices, it refers to the spraying device closest to the gas inlet) is 800-6000 mm (preferably 1000-5000 mm), and / or the inner diameter of the gas inlet is 800-1900 mm (preferably 900-1700 mm), and / or the linear velocity of the reaction product in the absorption device is 0.6-1.5 m / s (preferably 0.7-1.3 m / s), and / or the mass flow ratio of the spray liquid to the reaction product is 15-25:

1.

10. The manufacturing method of claim 1, wherein the internal space of the absorption device between the gas inlet and the spraying device (when there are multiple spraying devices, it refers to the spraying device closest to the gas inlet) is not provided with a mechanical component that can substantially affect the flow of the gas.

11. The manufacturing method according to claim 7, wherein the angle between the projections of the spray liquid inlets of the one spray device and the other spray device on the cross section is 180°.

12. The absorption device of claim 11, wherein among all the spray devices, the angle between the projections of the spray liquid inlets of any two odd-numbered spray devices on the cross section is 0°, the angle between the projections of the spray liquid inlets of any two even-numbered spray devices on the cross section is 0°, and the angle between the projections of the spray liquid inlets of any odd-numbered spray device and any even-numbered spray device on the cross section is 180°.

13. The absorption device of claim 11, wherein the nozzle comprises a nozzle inlet, a rotation chamber, and a nozzle outlet, wherein the rotation chamber is configured such that the spray liquid entering from the nozzle inlet leaves the nozzle outlet in a rotating manner after passing through the rotation chamber.

14. The absorption device according to claim 11, wherein on at least one (preferably all) of the second spray pipes, two adjacent (preferably all) nozzles located on the same side of the second spray pipe are configured so that the spray liquid is sprayed in the same rotation direction.

15. The absorption device according to claim 14, wherein all nozzles on opposite sides of two of the second spray pipes adjacent to each other are constructed so that the spray liquid is sprayed in opposite rotation directions.

16. The absorption device according to claim 14, wherein on at least one (preferably all) of the second spray pipes, at least one (preferably all) nozzles located on one side of the second spray pipe are constructed so that the spray liquid is sprayed in a rotation direction A, and at least one (preferably all) nozzles located on the other side of the second spray pipe are constructed so that the spray liquid is sprayed in a rotation direction B, wherein the rotation direction A is opposite to the rotation direction B.

17. The absorption device according to claim 16, wherein among all the nozzles of the spraying device, the number of nozzles spraying the spray liquid in the rotation direction A is equal to or substantially equal to the number of nozzles spraying the spray liquid in the rotation direction B.

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