Rectification equipment for preparing high-purity methylhydrazine

Abstract

The application relates to a rectification equipment for preparing high-purity methylhydrazine and relates to the technical field of rectification equipment; the rectification equipment for preparing high-purity methylhydrazine comprises a rectification kettle and a rectification tower, a gas outlet is further arranged at the top of the rectification tower, a gas outlet pipe is arranged at the gas outlet, a water sprinkling mechanism is further arranged at the top of the rectification tower, the water sprinkling mechanism comprises a water passing pipe and a water sprinkling disc, one end of the water passing pipe is used for connecting a water source, the other end of the water passing pipe extends into the top of the rectification tower and is communicated with the water sprinkling disc, and a plurality of water sprinkling nozzles are arranged at the bottom of the water sprinkling disc. The application has the effect of reducing the concentration of 1,1-dimethylhydrazine at the gas outlet of the rectification tower, thereby improving the preparation safety.

Description

Technical Field

[0001] This application relates to the field of distillation equipment technology, and in particular to a distillation apparatus for the preparation of high-purity methylhydrazine. Background Technology

[0002] Methylhydrazine, also known as monomethylhydrazine, is a hydrazine derivative and an important intermediate in the fields of pharmaceuticals, chemicals, biochemicals, and pesticides. It is also often combined with oxidants such as nitrogen tetroxide to form binary liquid propellants used in the monitoring systems of space shuttles, spacecraft, and satellites.

[0003] In the production of methylhydrazine, the crude methylhydrazine solution is generally distilled through a distillation kettle and a distillation column to separate the methylhydrazine from various hydrazine derivatives such as 1,1-dimethylhydrazine, 1,2-dimethylhydrazine, and 1,1,2-trimethylhydrazine contained in the crude methylhydrazine solution, and then discharged from the gas outlet at the top of the distillation column to obtain high-purity methylhydrazine.

[0004] Regarding the aforementioned technologies, since 1,1-dimethylhydrazine has the lowest boiling point in the crude methylhydrazine solution, it will vaporize first during the distillation process in the distillation column. After leaving the solution, it will rise to the outlet at the top of the distillation column, causing the concentration of 1,1-dimethylhydrazine at the outlet to gradually increase. Since 1,1-dimethylhydrazine has a low flash point, excessively high concentrations can easily react with oxygen at high temperatures and spontaneously explode. This means that excessively high concentrations of 1,1-dimethylhydrazine are prone to reacting and exploding upon contact with oxygen leaking into the air through the outlet gaps, increasing the probability of an explosion in the distillation column and reducing the safety of the preparation process. Therefore, improvements are needed. Summary of the Invention

[0005] To improve the safety of the preparation process, this application provides a distillation apparatus for preparing high-purity methylhydrazine.

[0006] This application provides a distillation apparatus for preparing high-purity methylhydrazine, which adopts the following technical solution:

[0007] A distillation apparatus for preparing high-purity methylhydrazine includes a distillation kettle and a distillation column. The top of the distillation column is provided with a gas outlet and a gas outlet pipe. The top of the distillation column is also provided with a water spraying mechanism, which includes a water pipe and a water spraying tray. One end of the water pipe is used to connect to a water source, and the other end extends into the top of the distillation column and connects to the water spraying tray. The bottom of the water spraying tray is provided with several water spray nozzles.

[0008] By adopting the above technical solution, compared with the prior art, the 1,1-dimethylhydrazine that vaporizes first rises to the gas outlet at the top of the distillation column after leaving the solution, thus gradually increasing the concentration of 1,1-dimethylhydrazine at the gas outlet and increasing the probability of the distillation column exploding. This application, through the setting of the water spraying mechanism, allows the water pipe to pass water from the water source into the water spraying tray, so that the water sprayed by the water spraying head can, after contacting the vaporized 1,1-dimethylhydrazine, drive the vaporized 1,1-dimethylhydrazine downward, diluting the 1,1-dimethylhydrazine near the gas outlet, thereby effectively reducing the concentration of 1,1-dimethylhydrazine at the gas outlet of the distillation column, reducing the probability of 1,1-dimethylhydrazine reacting with oxygen leaking into the air at the gas outlet and exploding, effectively reducing the probability of the distillation column exploding and improving the safety of the preparation.

[0009] Preferably, one end of the gas outlet pipe extends into the distillation column via the gas outlet port. A sealing mechanism is also provided on the end of the gas outlet pipe located inside the distillation column. The sealing mechanism includes a sealing frame and a rotating assembly. The sealing frame is rotatably connected to the gas outlet pipe. The sealing frame is used to close the opening at the corresponding end of the gas outlet pipe. The rotating assembly is used to drive the sealing frame to rotate.

[0010] By adopting the above technical solution and setting the sealing mechanism, the rotating component can drive the sealing frame to rotate, thereby sealing the end of the gas outlet pipe located inside the distillation column, further reducing the probability of air leaking in through the gas outlet entering the distillation column, thus effectively reducing the probability of 1,1-dimethylhydrazine reacting with oxygen in the leaked air, effectively reducing the probability of the distillation column exploding, and ensuring the safety of this application.

[0011] Preferably, the water spraying mechanism further includes an extension frame and a sliding assembly. The extension frame is located on the side of the water spraying disc near the closed frame. One end of the extension frame extends into the water spraying disc and is slidably connected to the water spraying disc. The sliding direction is towards the closed frame. An extension nozzle is provided at the bottom of the extension frame and is connected to the water spraying disc. The sliding assembly is used to drive the extension frame to slide.

[0012] By adopting the above technical solution, the extension frame and sliding assembly are configured such that when the closure frame rotates to close the end of the air outlet pipe, the sliding assembly can drive the extension frame to slide, causing the extension frame to gradually approach the closure frame. This allows the extended nozzles on the extension frame to spray water on the empty space between the water spray tray and the closure frame, thereby reducing the concentration of 1,1-dimethylhydrazine in that empty space and achieving dilution of the 1,1-dimethylhydrazine in that empty space.

[0013] Preferably, the sliding assembly includes an active frame and a transmission frame, both of which are located inside the sprinkler disc. The active frame is slidably connected to the sprinkler disc, and the sliding direction is the axial direction of the water pipe. One end of the transmission frame is rotatably connected to the active frame, and the other end is rotatably connected to the extension frame.

[0014] By adopting the above technical solution, the arrangement of the active frame and the transmission frame allows the active frame to move downwards under the scouring of the water flow when water is introduced into the sprinkler tray through the water pipe. This causes the transmission frame to drive the extension frame to slide, thereby driving the extension frame to slide. This replaces the active device that drives the extension frame to slide, effectively ensuring the smooth sliding of the extension frame and ensuring the smooth progress of this application.

[0015] Preferably, the active frame extends a sliding part on the side away from the water pipe. The sliding part is slidably connected to the inner wall of the sprinkler disc. A return spring is also sleeved on the sliding part. One end of the return spring abuts against the active frame, and the other end of the return spring abuts against the inner wall of the sprinkler disc.

[0016] By adopting the above technical solution and setting the return spring, when the water pipe stops supplying water to the sprinkler tray, the active frame can return to its initial position under the elastic force of the return spring, thereby allowing the extension frame to return to its initial position, thus reducing the impact of the extension frame on the rotation of the enclosure frame and effectively ensuring the smooth rotation of the enclosure frame.

[0017] Preferably, the top of the active frame is used to close the connection between the water pipe and the sprinkler plate. The top wall of the active frame is also provided with several water channels. One end of each water channel is located directly below the connection between the water pipe and the sprinkler plate, and the other end extends to the end of the active frame.

[0018] By adopting the above technical solution and setting up the water channel, when the water pipe stops supplying water to the sprinkler tray, the residual water at the bottom of the water pipe can flow into the sprinkler tray through the water channel when the active frame returns to its initial position under the elastic force of the return spring, thereby reducing the water accumulation in the water pipe.

[0019] Preferably, the rotating assembly includes a linkage frame, one end of which is rotatably connected to the extension frame, and the other end of which is rotatably connected to the enclosure frame.

[0020] By adopting the above technical solution and setting the linkage frame, when the extension frame is displaced, the extension frame can drive the linkage frame to displace as well, thereby causing the linkage frame to move away from the end of the extension frame and drive the sealing frame to rotate, thus realizing the linkage between the extension frame and the sealing frame. This effectively replaces the main component that drives the sealing frame to rotate, effectively ensuring the smooth rotation of the sealing frame and ensuring the sealing effect of the sealing frame on the air outlet pipe.

[0021] Preferably, a cooling mechanism is provided at one end of the extension frame near the closed frame. The cooling mechanism includes a rotating frame, a cooling nozzle, and a linkage component. The rotating frame is rotatably connected to the extension frame. The cooling nozzle is disposed on the rotating frame and communicates with the water spray plate. The linkage component is used to drive the cooling nozzle to rotate, so that the cooling nozzle faces the closed frame.

[0022] By adopting the above technical solution and configuring the cooling mechanism, when the enclosure rotates, the linkage component can drive the rotating frame to rotate, thereby causing the rotating frame to drive the cooling nozzle to rotate together. This causes the water outlet of the cooling nozzle to face the rotated enclosure, thereby cooling the enclosure. This allows 1,1-dimethylhydrazine near the enclosure to flow downwards after contacting the enclosure, further reducing the 1,1-dimethylhydrazine near the air outlet.

[0023] Preferably, the linkage assembly includes two linkage gears, one of which is connected to the linkage frame and the other is connected to the rotating frame, and the two linkage gears mesh with each other.

[0024] By adopting the above technical solution and setting the linkage components, the extension frame drives the closed frame to rotate through the linkage frame, thereby causing the linkage frame to rotate relative to the extension frame. During this process, the linkage frame can drive one of its linkage gears to rotate, which in turn causes another linkage gear to drive the rotating frame to rotate, thus driving the rotating frame. This effectively realizes the linkage between the closed frame, the extension frame, and the rotating frame, replacing the active device that drives the rotating frame to rotate and ensuring the smooth rotation of the rotating frame.

[0025] Preferably, a pressure stabilizing mechanism is also provided on one side of the distillation column. The pressure stabilizing mechanism includes a nitrogen tank and a pressure stabilizing pipe. The nitrogen tank is used to store nitrogen, and one end of the pressure stabilizing pipe is connected to the nitrogen tank and the other end is connected to the distillation kettle.

[0026] By adopting the above technical solution and configuring the pressure stabilizing mechanism, when the gas pressure in the distillation kettle and distillation column decreases, nitrogen from the nitrogen tank can be introduced into the distillation kettle through the pressure stabilizing pipe, thereby increasing the gas pressure in the distillation kettle and distillation column, ensuring the stability of the gas pressure in the distillation kettle and distillation column, and thus reducing the probability that outside air will enter the distillation column through the air inlet due to excessively low gas pressure in the distillation column, thereby reducing the probability that 1,1-dimethylhydrazine will react with oxygen in the introduced air.

[0027] In summary, this application includes at least one of the following beneficial technical effects:

[0028] The water spraying mechanism is designed so that the water pipe can deliver water from the water source into the spraying tray. This allows the water sprayed from the sprinkler head to come into contact with the vaporized 1,1-dimethylhydrazine, causing the vaporized 1,1-dimethylhydrazine to move downwards. This dilutes the 1,1-dimethylhydrazine near the gas outlet, effectively reducing the concentration of 1,1-dimethylhydrazine at the gas outlet of the distillation column. This reduces the probability of 1,1-dimethylhydrazine reacting with oxygen leaking into the air at the gas outlet and causing an explosion, thus effectively reducing the probability of an explosion in the distillation column and improving the safety of the preparation process.

[0029] The sealing mechanism is designed so that the rotating component can drive the sealing frame to rotate, thereby sealing the end of the gas outlet pipe located inside the distillation column. This further reduces the probability of air leaking into the distillation column through the gas outlet, thus effectively reducing the probability of 1,1-dimethylhydrazine reacting with oxygen in the leaked air, effectively reducing the probability of the distillation column exploding, and ensuring the safety of this application.

[0030] The cooling mechanism is designed so that when the enclosure rotates, the linkage component can drive the rotating frame to rotate, which in turn causes the cooling nozzle to rotate as well. This causes the water outlet of the cooling nozzle to face the rotated enclosure, thereby cooling the enclosure. This allows 1,1-dimethylhydrazine near the enclosure to flow downwards after contacting the enclosure, further reducing the 1,1-dimethylhydrazine near the air outlet. Attached Figure Description

[0031] Figure 1 This is a schematic diagram illustrating the overall structure of the distillation equipment for preparing high-purity methylhydrazine in the embodiments of this application.

[0032] Figure 2 This is a schematic diagram illustrating the structure of the active frame in the embodiments of this application.

[0033] Figure 3 This is a schematic diagram illustrating the cooling mechanism in the embodiments of this application.

[0034] Explanation of reference numerals in the attached drawings: 1. Distillation vessel; 2. Distillation column; 21. Gas outlet; 3. Gas outlet pipe; 31. Gas outlet valve; 4. Sprinkler mechanism; 41. Water pipe; 42. Sprinkler tray; 421. Sprinkler nozzle; 43. Water storage tank; 44. Water pump; 45. Extension frame; 451. Drive unit; 46. Sliding assembly; 461. Active frame; 4611. Sliding unit; 462. Transmission frame; 47. Return spring; 5. Water trough; 6. Extension nozzle; 61. Connecting hose; 7. Sealing mechanism; 71. Sealing frame; 72. Rotating assembly; 721. Linkage frame; 8. Cooling mechanism; 81. Rotating frame; 82. Cooling nozzle; 83. Linkage assembly; 831. Linkage gear; 9. Pressure stabilizing mechanism; 91. Nitrogen tank; 92. Pressure stabilizing pipe; 93. Gas valve. Detailed Implementation

[0035] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0036] This application discloses a distillation apparatus for the preparation of high-purity methylhydrazine. (Refer to...) Figure 1 and Figure 2 The distillation equipment for preparing high-purity methylhydrazine includes a distillation kettle 1 and a distillation column 2. The top of the distillation column 2 is also equipped with a gas outlet 21, and a gas outlet pipe 3 is installed at the gas outlet 21. A water spraying mechanism 4 is also installed at the top of the distillation column 2. The water spraying mechanism 4 includes a water pipe 41 and a water spraying tray 42. One end of the water pipe 41 is connected to a water source, and the other end extends into the top of the distillation column 2 and connects to the water spraying tray 42. Several water spray nozzles 421 are installed at the bottom of the water spraying tray 42.

[0037] Reference Figure 1 The distillation vessel 1 is placed on the ground, and its top is connected to the bottom of the distillation column 2 via a pipe. The distillation vessel 1 is used to heat the crude methylhydrazine solution, thereby causing various hydrazine derivatives such as 1,1-dimethylhydrazine, 1,2-dimethylhydrazine, and 1,1,2-trimethylhydrazine in the crude methylhydrazine solution to volatilize sequentially according to their different boiling points. The distillation column 2 is used to achieve gas-liquid equilibrium of the introduced gas and to further separate the gas.

[0038] Reference Figure 1 and Figure 2 One end of the vent pipe 3 extends into the vent outlet 21 and is pressed against the inner wall of the vent outlet 21 to ensure a sealed connection between the vent pipe 3 and the vent outlet 21. The other end of the vent pipe 3 is connected to the waste gas treatment device or reflux device in the methylhydrazine preparation process to discharge the gas volatilized during the heating process outside the distillation column 2. A vent valve 31 is also provided on the vent pipe 3 to control whether the vent pipe 3 is connected or not.

[0039] Reference Figure 1 and Figure 2The sprinkler system 4 also includes a water storage tank 43, which stores water for spraying. The bottom of the water storage tank 43 is connected to the end of the water pipe 41 away from the distillation column 2. A water pump 44 is also installed at the end of the water pipe 41 connected to the water storage tank 43 to pump water out of the water storage tank 43. The other end of the water pipe 41 extends downward from the top of the distillation column 2 into the distillation column 2 and extends into the top of the chamber in the sprinkler plate 42.

[0040] Reference Figure 2 and Figure 3 The water spray plate 42 is fixedly installed at the top of the inside of the distillation column 2 by bolts. Each water spray head 421 is fixedly installed on the bottom of the water spray plate 42, and the water outlet is set vertically downward. The water inlet of each water spray head 421 is connected to the chamber inside the water spray plate 42, so that the water in the water spray plate 42 can enter the water spray head 421.

[0041] Reference Figure 2 and Figure 3 The sprinkler mechanism 4 also includes an extension frame 45 and a sliding assembly 46. The sliding assembly 46 includes an active frame 461 and a transmission frame 462. Both the active frame 461 and the transmission frame 462 are located within the cavity of the sprinkler disc 42. The top of the active frame 461 abuts against the inner top wall of the sprinkler disc 42 and is located directly below the top of the water pipe 41. A sliding part 4611 extends vertically downward from the bottom of the active frame 461. The sliding part 4611 passes through the bottom of the sprinkler disc 42 and abuts against the inner wall of the sprinkler disc 42, thereby slidingly connecting with the inner wall of the sprinkler disc 42, and making the sliding direction vertical.

[0042] Reference Figure 2 and Figure 3 A return spring 47 is also fitted on the sliding part 4611. In this embodiment, the return spring 47 is configured as a compression spring. One end of the return spring 47 abuts against the bottom of the active frame 461, and the other end abuts against the inner bottom wall of the inner cavity of the sprinkler plate 42, so that the return spring 47 can be compressed when the active frame 461 slides downward, thereby storing elastic potential energy.

[0043] Reference Figure 2 and Figure 3 The top outer side of the active frame 461 is also bent downwards to form an incomplete spherical surface at the top of the active frame 461. The distance from the outer side of the active frame 461 to its own axis is greater than the radius of the water pipe 41, so that when the active frame 461 abuts against the inner top wall of the sprinkler plate 42, it can seal the opening at the connection between the water pipe 41 and the sprinkler plate 42.

[0044] Reference Figure 2 and Figure 3The top of the active frame 461 is also provided with several water channels 5. One end of each water channel 5 extends from the center of the top of the active frame 461 to the side end close to the active frame 461, so that when the active frame 461 closes the top of the water pipe 41, the water at the top of the water pipe 41 can flow along the water channel 5 to the cavity of the sprinkler plate 42.

[0045] Referring to the figure, the extension frame 45 is located on the side of the sprinkler disc 42 near the air outlet pipe 3. The extension frame 45 is slidably connected to the bottom of the sprinkler disc 42 via a slide rail, and the straight line of the sliding direction passes through the location of the air outlet pipe 3. The extension frame 45 is also provided with a drive unit 451, which is integrally formed with the extension frame 45. The drive unit 451 extends from the side wall of the sprinkler disc 42 into the cavity of the sprinkler disc 42 and abuts against the inner wall of the sprinkler disc 42 for slidable connection.

[0046] Reference Figure 2 and Figure 3 In this embodiment, two transmission frames 462 are provided, located on opposite sides of the drive unit 451. One end of each transmission frame 462 is rotatably connected to the bottom of the corresponding drive frame 461 via a pin, and the other end is rotatably connected to the drive unit 451 via a pin, so that when the drive frame 461 slides downward, the drive frame 461 can drive the extension frame 45 to slide closer to the air outlet pipe 3 via the transmission frame 462.

[0047] Reference Figure 2 and Figure 3 Several extension nozzles 6 are fixedly installed at the bottom of the extension frame 45, with the water outlet of each extension nozzle 6 facing vertically downwards. The extension frame 45 has several internal chambers, and the water inlet of each extension nozzle 6 communicates with a chamber within the extension frame 45. Several connecting hoses 61 are also provided on the extension frame 45. One end of each connecting hose 61 communicates with the bottom of a chamber within the sprinkler disc 42, and the other end communicates with a corresponding chamber on the extension frame 45, allowing water from the sprinkler disc 42 to enter the extension nozzle 6 via the connecting hoses 61.

[0048] Reference Figure 2 and Figure 3 A sealing mechanism 7 is also provided at one end of the outlet pipe 3 located inside the distillation column 2. The sealing mechanism 7 includes a sealing frame 71 and a rotating assembly 72. The rotating assembly 72 includes a linkage frame 721. In this embodiment, the number of linkage frames 721 is set to two, and they are respectively located on opposite sides of the extension frame 45. The top of the sealing frame 71 is rotatably connected to the distillation column 2 by a pin. The cross-sectional area of ​​the sealing frame 71 is larger than the cross-sectional area of ​​the end of the outlet pipe 3, so that the sealing frame 71 can fully seal the end of the outlet pipe 3.

[0049] Reference Figure 2 and Figure 3 One end of each linkage frame 721 is rotatably connected to the end of the extension frame 45 near the air outlet pipe 3 via a pin, and the other end of each linkage frame 721 is rotatably connected to the middle of the enclosure frame 71 via a pin, so that the extension frame 45 can drive the enclosure frame 71 to rotate through the linkage frame 721.

[0050] Reference Figure 2 and Figure 3 Initially, the top of the active frame 461 is in contact with the inner top wall of the sprinkler plate 42, and the extension frame 45 is located at the end of its sliding path away from the air outlet pipe 3. At this time, the closed frame 71 is in the open state. When the concentration of 1,1-dimethylhydrazine near the air outlet 21 is too high, the water pump 44 draws water from the water storage tank 43 into the water pipe 41. When the water pipe 41 flows water into the sprinkler plate 42, the active frame 461 slides downward under the force of the water flow. At this time, the active frame 461 drives the drive unit 451 to slide through the transmission frame 462, thereby causing the extension frame 45 to gradually approach the air outlet pipe 3.

[0051] Reference Figure 2 and Figure 3 During this process, the extension frame 45 drives the sealing frame 71 to rotate and approach the end of the air outlet pipe 3 through the linkage frame 721, so that when the sealing frame 71 rotates and comes into contact with the end of the air outlet pipe 3, it seals the end of the air outlet pipe 3.

[0052] Reference Figure 2 and Figure 3 When the 1,1-dimethylhydrazine near the air outlet 21 drops to the specified standard, the water pipe 41 stops supplying water to the sprinkler plate 42. At this time, the active frame 461 returns to its initial position under the action of the return spring 47, thereby causing the sealing frame 71 to rotate, releasing the seal on the air outlet 3, so that 1,1-dimethylhydrazine can be discharged again through the air outlet 3.

[0053] Reference Figure 2 and Figure 3 A cooling mechanism 8 is also provided at one end of the extension frame 45 near the air outlet pipe 3. The cooling mechanism 8 includes a rotating frame 81, a cooling nozzle 82, and a linkage assembly 83. The two ends of the rotating frame 81 extend out of the end of the extension frame 45 near the air outlet pipe 3 along its own length direction and are rotatably connected to the extension frame 45. In this embodiment, the number of linkage assemblies 83 is set to two, and they are arranged one-to-one with the two linkage frames 721.

[0054] Reference Figure 2 and Figure 3Each linkage assembly 83 includes two linkage gears 831. One linkage gear 831 is fixedly connected to the end of the corresponding transmission frame 462 away from the closed frame 71 by welding, and its axis is the same as the rotation axis of the corresponding transmission frame 462 and the extension frame 45. The other linkage gear 831 is fixedly sleeved on the corresponding end of the rotating frame 81 that extends out of the extension frame 45. The two linkage gears 831 in each linkage assembly 83 are meshed together.

[0055] Reference Figure 2 and Figure 3 The number of cooling nozzles 82 is set to several, and they are all fixedly installed on the rotating frame 81. The water outlet of each cooling nozzle 82 faces the bottom of the rotating frame 81, and the water inlet is connected to the chamber inside the water spray plate 42 through a hose, so that the water in the water spray plate 42 can flow to the cooling nozzle 82 through the hose.

[0056] Reference Figure 2 and Figure 3 Initially, when the extension frame 45 is located at the end of its sliding path away from the closed frame 71, the water outlet of the cooling nozzle 82 is not facing the closed frame 71. As the extension frame 45 slides closer to the closed frame 71, each linkage frame 721 rotates relative to the extension frame 45. During this process, the linkage frame 721 drives the corresponding linkage gear 831 to rotate, which in turn drives the linkage gear 831 meshing with it to rotate, thereby causing the rotating frame 81 to rotate. This causes the water outlet of the cooling nozzle 82 on the rotating frame 81 to gradually face the side of the closed frame 71 closer to the extension frame 45, allowing the water sprayed from the cooling nozzle 82 to fall onto the closed frame 71 and cool it down.

[0057] Reference Figure 1 A pressure stabilizing mechanism 9 is also provided on one side of the distillation column 2. The pressure stabilizing mechanism 9 includes a nitrogen tank 91 and a pressure stabilizing pipe 92. The nitrogen tank 91 is used to store nitrogen. One end of the pressure stabilizing pipe 92 is connected to the top of the nitrogen tank 91, and the other end is connected to the bottom of the distillation kettle 1, so as to deliver nitrogen into the distillation kettle 1, thereby ensuring the stability of the gas pressure in the distillation kettle 1 and the distillation column 2. A vent valve 93 is also provided on the pressure stabilizing pipe 92 to control the opening and closing of the pressure stabilizing pipe 92. In this embodiment, the vent valve 93 is a solenoid valve.

[0058] The implementation principle of the distillation apparatus for preparing high-purity methylhydrazine in this embodiment is as follows: When the concentration of 1,1-dimethylhydrazine at the outlet 21 is too high, the water pump 44 draws water from the water storage tank 43 into the water pipe 41, and the water enters the water spray tray 42 through the water pipe 41 and is then discharged through the water spray nozzle 421. This allows the water sprayed from the water spray nozzle 421 to come into contact with the vaporized 1,1-dimethylhydrazine, causing the vaporized 1,1-dimethylhydrazine to move downwards, diluting the 1,1-dimethylhydrazine near the outlet 21, thereby effectively reducing the concentration of 1,1-dimethylhydrazine at the outlet 21 of the distillation column 2.

[0059] During this process, the active frame 461 slides, which in turn drives the extension frame 45 to slide via the transmission frame 462. This causes the extension frame 45 to rotate via the linkage frame 721, thereby closing the air outlet pipe 3. When the 1,1-dimethylhydrazine near the air outlet 21 drops to the specified level, the water pipe 41 stops supplying water to the sprinkler tray 42. At this point, the active frame 461 returns to its initial position under the action of the return spring 47, causing the closing frame 71 to rotate and release the seal on the air outlet pipe 3, allowing the 1,1-dimethylhydrazine to flow out again through the air outlet pipe 3.

[0060] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A rectification device for preparing high-purity methylhydrazine, comprising a rectification kettle (1) and a rectification tower (2), a gas outlet (21) is further arranged at the top of the rectification tower (2), and a gas outlet pipe (3) is arranged at the gas outlet (21), characterized in that: The top of the rectifying tower (2) is also provided with a sprinkling mechanism (4), which comprises a water pipe (41) and a sprinkling disc (42). One end of the water pipe (41) is used for connecting a water source, the other end extends into the top of the rectifying tower (2) and communicates with the sprinkling disc (42). The bottom of the sprinkling disc (42) is provided with a plurality of sprinkling nozzles (421). One end of the air outlet pipe (3) extends into the rectifying tower (2) through the air outlet (21). The end of the air outlet pipe (3) in the rectifying tower (2) is also provided with a closing mechanism (7). The closing mechanism (7) comprises a closing frame (71) and a rotating assembly (72). The closing frame (71) is rotatably connected with the air outlet pipe (3). The closing frame (71) is used for closing the opening of the corresponding end of the air outlet pipe (3). The rotating assembly (72) is used for driving the closing frame (71) to rotate. The sprinkling mechanism (4) also comprises an extension frame (45) and a sliding assembly (46). The extension frame (45) is located on the side of the sprinkling disc (42) close to the closing frame (71). One end of the extension frame (45) extends into the sprinkling disc (42) and is slidably connected with the sprinkling disc (42). The sliding direction is the direction close to the closing frame (71). The bottom of the extension frame (45) is provided with an extension nozzle (6). The extension nozzle (6) communicates with the sprinkling disc (42). The sliding assembly (46) is used for driving the extension frame (45) to slide. The sliding assembly (46) comprises a driving frame (461) and a transmission frame (462). The driving frame (461) and the transmission frame (462) are both located in the sprinkling disc (42). The driving frame (461) is slidably connected with the sprinkling disc (42). The sliding direction is the axis direction of the water pipe (41). One end of the transmission frame (462) is rotatably connected with the driving frame (461). The other end is rotatably connected with the extension frame (45). The side of the driving frame (461) away from the water pipe (41) further extends a sliding part (4611). The sliding part (4611) is slidably connected with the inner wall of the sprinkling disc (42). A return spring (47) is further sleeved on the sliding part (4611). One end of the return spring (47) abuts against the driving frame (461). The other end abuts against the inner wall of the sprinkling disc (42). The top of the driving frame (461) is used for closing the communication between the water pipe (41) and the sprinkling disc (42). A plurality of water grooves (5) are formed in the top wall of the driving frame (461). One end of each water groove (5) is located directly below the communication between the water pipe (41) and the sprinkling disc (42). The other end extends to the end of the driving frame (461). The extension frame (45) is further provided with a cooling mechanism (8) near one end of the closing frame (71), the cooling mechanism (8) comprises a rotating frame (81), a cooling nozzle (82) and a linkage assembly (83), the rotating frame (81) is rotatably connected with the extension frame (45), the cooling nozzle (82) is arranged on the rotating frame (81) and communicates with the water tray (42), and the linkage assembly (83) is used for driving the cooling nozzle (82) to rotate, so that the cooling nozzle (82) faces the closing frame (71).

2. The rectification apparatus for producing high-purity methylhydrazine according to claim 1, characterized by: The rotating assembly (72) comprises a linkage frame (721), one end of the linkage frame (721) is rotatably connected with the extension frame (45), and the other end of the linkage frame (721) is rotatably connected with the closing frame (71).

3. The rectification apparatus for producing high-purity methylhydrazine according to claim 2, characterized by: The linkage assembly (83) comprises two linkage gears (831), one of the linkage gears (831) is connected with the linkage frame (721), and the other linkage gear (831) is connected with the rotating frame (81), and the two linkage gears (831) are engaged.

4. The rectification apparatus for producing high-purity methylhydrazine according to claim 1, wherein: One side of the rectifying tower (2) is further provided with a pressure stabilizing mechanism (9), the pressure stabilizing mechanism (9) comprises a nitrogen tank (91) and a pressure stabilizing pipe (92), the nitrogen tank (91) is used for storing nitrogen, one end of the pressure stabilizing pipe (92) communicates with the nitrogen tank (91), and the other end of the pressure stabilizing pipe (92) communicates with the rectifying kettle (1).

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