Equipment for preparing ultra-pure nitrogen

Abstract

The invention discloses equipment for preparing ultra-pure nitrogen, which relates to the technical field of dehydrogenation equipment, comprises a lower tower, an upper tower and a dehydrogenation tower, and is used for removing a hydrogen component in high-purity nitrogen. According to the device, pure dry air enters the main heat exchanger and exchanges heat with backflow low-temperature waste gas and product nitrogen in the main heat exchanger, then a part of air returns to the main heat exchanger after being refrigerated by the expansion machine, and the rest of air enters the lower tower after being cooled and is rectified and separated into high-purity nitrogen and oxygen-enriched liquid air; part of liquid air enters a dehydrogenation tower condenser in a throttling manner and returns to the upper tower after being gasified; and the ultra-pure nitrogen is extracted from the bottom of the dehydrogenation tower and is output after being reheated by the main heat exchanger, the low-pressure pure nitrogen at the top of the upper tower is condensed into liquid nitrogen, the part of the low-pressure pure nitrogen flows back to the upper tower, and the part of the low-pressure pure nitrogen is pressurized by a liquid nitrogen pump and enters the lower tower, so that the nitrogen extraction rate is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of dehydrogenation equipment, and more particularly to an equipment for preparing ultrapure nitrogen. Background Art

[0002] A distillation tower is a tower-type gas-liquid contact device for distillation. It utilizes the different volatilities of the components in the mixture, that is, the different vapor pressures of the components at the same temperature, to transfer the light components (low boiling substances) in the liquid phase to the gas phase, and the heavy components (high boiling substances) in the gas phase to the liquid phase, thereby achieving the purpose of separation. Therefore, distillation towers are often used to purify substances in many industrial production.

[0003] For example, a Chinese patent with application number CN202411128477.8 specifically discloses a distillation tower for producing sustainable aviation fuel, including a tower body and a tower plate. An overflow weir is provided on the tower plate. The tower plate, the tower body and the overflow weir form a receiving tank for receiving reflux liquid. A plurality of bubble cap mechanisms are provided on the tower plate. The bubble cap mechanisms include a fixed sleeve and a movable sleeve. The fixed sleeve has an opening at the top and is fixed on the tower plate. The movable sleeve has a closed top and an opening at the bottom and is sealed and slidably assembled in the fixed sleeve in the up-down direction. An elastic member for pulling the movable sleeve downward is provided between the movable sleeve and the fixed sleeve. An air inlet pipe extending into the movable sleeve is provided on the tower plate. The above patent adopts the design of movable bubble and elastic parts, so that the gas is first stored in the bubble mechanism and then contacts with the reflux liquid. Theoretically, this design prolongs the contact time between the gas phase and the liquid phase, creating more favorable conditions for gas-liquid mass transfer. However, in the actual operation process, there are some problems that cannot be ignored. During the gas storage stage, due to the continuous entry of gas, the bubble will move upward under the action of gas pressure. This movement causes the path length of the bubble in the reflux liquid to be greatly shortened, that is, the effective stroke of gas-liquid mass transfer is reduced.

[0004] In addition, when the bubbles are discharged, the gas pre-stored in the bubble is compressed to form high-pressure gas. When the high-pressure gas is discharged, the bubbles are ejected at high speed, which greatly shortens the residence time of the bubbles in the reflux liquid. In the process of gas-liquid heat exchange, the residence time is one of the key factors affecting the exchange effect. If the residence time is too short, the heat exchange between the gas and the liquid cannot be fully carried out. Combining the above factors, the efficiency of separating nitrogen from the mixed gas is ultimately significantly reduced, making it difficult to meet the requirements of efficient separation. Summary of the invention

[0005] In view of the deficiencies of the prior art, the present invention provides a device for preparing ultrapure nitrogen, which solves the problems raised in the above background technology.

[0006] The technical solution of the present invention is as follows: To achieve the above objectives, the present invention is implemented through the following technical solutions: an apparatus for preparing ultrapure nitrogen, comprising a lower tower, an upper tower, a dehydrogenation tower body and a plurality of tower plates axially arranged in the dehydrogenation tower body, wherein the surface of the tower plate close to the top of the dehydrogenation tower body is provided with a plurality of riser pipes for allowing rising gas to enter, the top of the riser pipe is provided with a bubble cap that can move back and forth and rotate along its axial direction, and the riser pipe is provided with a power component that can transmit power to the bubble cap; The power component comprises a driving fan rotatably arranged around the air riser, a driving rod is fixedly connected to the top of the driving fan, a blocking driving component is fixedly connected to the top of the bubble cap, and a plurality of auxiliary driving plates that can be snapped onto the blocking driving component are arranged on the top of the driving rod; A first elastic member capable of causing the bubble cap to return to its original position is arranged on the top of the riser.

[0007] Preferably, a plurality of air inlets adapted to the riser pipes are provided on the horizontal plane of the tower plate.

[0008] Preferably, one end of the first elastic member away from the riser is fixedly connected to a first ring plate, and one end of the first ring plate away from the first elastic member is rotatably connected to the inner top surface of the bubble.

[0009] Preferably, the end of the driving rod close to the driving fan is rotatably connected to a fixing plate, and the outer peripheral surface of the fixing plate is fixedly connected to a plurality of fixing columns, one end of which is arranged on the riser pipe, the middle part of the driving rod is rotatably connected to a screw sleeve, and the bottom of the screw sleeve is fixedly connected to a plurality of fixing rods, one end of which is arranged on the riser pipe; The inner top surface of the bubble cap is fixedly connected with an auxiliary movable barrel, the bottom of the auxiliary movable barrel is movably connected to the screw sleeve, and a convex block which is clamped on the spiral groove of the screw sleeve protrudes from the bottom of the auxiliary movable barrel.

[0010] Preferably, the blocking drive component includes a driving barrel fixedly connected to the top surface of the bubble, a plurality of driving baffles are evenly and fixedly connected to the inner circumference of the driving barrel, the top of the driving rod is connected to an auxiliary positioning cylinder along its axial sliding connection, a plurality of limit rods are vertically arranged on the top of the driving rod, the auxiliary positioning cylinder is rotatably connected to the bottom of the driving barrel, and the top of the driving rod extends into the driving barrel.

[0011] Preferably, an auxiliary circular plate is fixedly connected to the top of the driving rod, and a plurality of limiting grooves are evenly opened on the outer circumference of the auxiliary circular plate. The plurality of auxiliary driving plates are respectively slidably connected in the corresponding limiting grooves, and one end of the auxiliary driving plate away from the inner circumference of the driving barrel is fixedly connected to a second elastic member, and one end of the second elastic member away from the auxiliary driving plate is fixedly connected in the limiting groove.

[0012] Preferably, the bottom of the outer circumference of the bubble is rotatably connected with an auxiliary connecting cylinder, the outer circumference of the auxiliary connecting cylinder is provided with a sliding mounting cylinder that can slide along its axial direction, and the outer circumference of the sliding mounting cylinder is evenly fixedly connected with multiple driving plates.

[0013] Preferably, a floating plate is fixedly connected to the surface of the sliding mounting cylinder away from the tower plate.

[0014] Preferably, one outer surface of the driving plate is an inclined surface.

[0015] Preferably, a plurality of sliding grooves are evenly formed on the outer circumference of the auxiliary connecting cylinder, and a plurality of convex plates are protruded from the inner circumference of the sliding mounting cylinder, and the plurality of convex plates are respectively slidably connected in the corresponding sliding grooves.

[0016] Beneficial Effects The present invention provides a device for preparing ultrapure nitrogen, which has the following beneficial effects: 1. The equipment for preparing ultrapure nitrogen, through the arrangement of a driving fan, a driving rod, an auxiliary driving plate and a blocking driving component, can increase the speed of the driving fan as the rising speed of nitrogen is accelerated, and the gas flow rate increases, thereby increasing the speed of the driving fan. As the speed of the driving fan increases, the auxiliary driving plate is thrown out due to the increase in centrifugal force. When the auxiliary driving plate is clamped on the driving baffle, it will drive the bubble cap to rotate together. Due to the special design of the screw sleeve, the bubble cap will move downward when rotating. In this way, the mixed gas entering the riser from the air inlet will have a longer path to be discharged from the bottom of the bubble cap, and the bubble rising path will also be correspondingly longer, which greatly enhances the effect of nitrogen being separated from the reflux liquid.

[0017] 2. The equipment for preparing ultra-pure nitrogen, through the setting of the dehydrogenation tower body, not only does not need to consider the service life of the adsorbent, but also reduces the subsequent maintenance costs.

[0018] 3. The equipment for preparing ultra-pure nitrogen, through the setting of the driving plate, can cause a series of physical phenomena when the driving plate rotates. On the one hand, it will extend the movement trajectory of the bubbles in the reflux liquid, that is, by increasing the travel path of the bubbles, the interaction between gas and liquid is strengthened; on the other hand, the rotation of the driving plate will produce a shearing and crushing effect on the rising bubbles, breaking large bubbles into multiple small bubbles, greatly increasing the contact area between nitrogen and reflux liquid. This series of action mechanisms can significantly improve the mass transfer efficiency between the liquid phase and the gas phase, thereby greatly improving the conversion efficiency between the flowing liquid and nitrogen.

[0019] 4. The equipment for preparing ultra-pure nitrogen, through the setting of the driving plate, can cause the reflux liquid to generate additional turbulence when the driving plate rotates. This turbulence will form complex eddies and circulations in the liquid, further enhancing the energy exchange between different layers of the liquid. Under the action of this strong turbulence, the originally stratified liquid is difficult to maintain a stable temperature stratification state, and the temperature stratification phenomenon will be significantly destroyed. At the same time, the mechanical energy generated by the stirring of the driving plate will intensify the mixing between the various parts of the reflux liquid. The reflux liquid with a lower temperature close to the tower plate and the reflux liquid with a higher temperature close to the nitrogen will be forced to mix, and the temperature difference will gradually decrease during the mixing process, thereby effectively destroying the stratification phenomenon of liquid ammonia formed due to different temperatures, thereby greatly increasing the conversion efficiency between the reflux liquid and nitrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the process for preparing ultrapure nitrogen according to the present invention; Figure 2 This is a schematic diagram of the structure of the dehydrogenation tower body of the present invention; Figure 3 It is a partial cross-sectional structural schematic diagram of the dehydrogenation tower body of the present invention when viewed from the front; Figure 4 It is a structural schematic diagram of the tower plate of the present invention when viewed from the front; Figure 5 For the present invention Figure 4 The enlarged structural diagram at A in the middle; Figure 6 It is a schematic diagram of the matching structure of the sliding installation cylinder and the driving plate of the present invention; Figure 7 This is a schematic diagram of the structure of the auxiliary connecting tube of the present invention; Figure 8 It is a schematic diagram of the matching structure of the driving rod and the auxiliary positioning cylinder of the present invention; Fig. 9 It is a schematic diagram of the cross-sectional structure of the driving barrel of the present invention when viewed from above.

[0021] In the figure: 1. dehydrogenation tower body; 2. tower plate; 3. riser; 4. bubble cap; 5. drive barrel; 6. drive plate; 7. drive fan; 8. first elastic member; 9. drive rod; 10. drive baffle; 11. auxiliary circular plate; 12. auxiliary drive plate; 13. second elastic member; 14. first ring plate; 15. auxiliary moving barrel; 16. screw sleeve; 17. floating plate; 18. fixing rod; 19. auxiliary connecting cylinder; 20. sliding mounting cylinder; 21. air inlet; 22. slide groove; 23. auxiliary positioning cylinder; 24. limit rod; 25. main heat exchanger; 26. expander; 27. subcooler; 28. lower tower; 29. ​​lower tower condenser evaporator; 30. dehydrogenation tower condenser; 31. dehydrogenation tower evaporator; 32. upper tower; 33. upper tower condenser; 34. liquid nitrogen pump. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Embodiment 1 Ultrapure nitrogen is widely used in the field of electronics and semiconductor manufacturing. It is usually used as a protective gas and carrier gas to ensure the excellence of the process and avoid the influence of impurities. For example, in the chemical vapor deposition (CVD) process, ultrapure nitrogen is used as a carrier gas, a carrier gas for liquid diffusion sources, and a protective gas for devices in high-temperature diffusion furnaces. However, in the field of semiconductor chips, there are very strict requirements on the purity of nitrogen (the oxygen content cannot exceed 1ppm and the hydrogen content cannot exceed 1ppb). Conventional high-purity nitrogen contains hydrogen components and cannot effectively remove hydrogen. High-purity nitrogen obtained by low-temperature deep-cold distillation technology is usually used, and then introduced into a hydrogen removal purification device, and hydrogen is adsorbed and removed by an adsorbent, thereby obtaining ultrapure nitrogen equipment; The existing high-purity nitrogen purification equipment needs to add a hydrogen removal purification device, which not only needs to consider the service life of the adsorbent, but also invisibly increases the subsequent maintenance costs. This embodiment is specially invented to solve the above problems.

[0024] See also Figure 1 The present invention provides a technical solution: an apparatus for preparing ultrapure nitrogen, comprising a lower tower 28, an upper tower 32, a dehydrogenation tower body 1 and a plurality of tower plates 2 axially arranged in the dehydrogenation tower body 1, wherein the apparatus for preparing ultrapure nitrogen also comprises an expander 26, a main heat exchanger 25, a subcooler 27, a lower tower condenser evaporator 29, a dehydrogenation tower condenser 30, a dehydrogenation tower evaporator 31 and an upper tower condenser 33; The pure dry air from which water, carbon dioxide and some hydrocarbons are removed is sent to the main heat exchanger 25, and heat is exchanged with the reflux low-temperature exhaust gas and the product nitrogen through the main heat exchanger 25. A stream is drawn from the middle of the main heat exchanger 25 as expansion air and enters the expander 26 for expansion and refrigeration. After expansion, it directly returns to the bottom of the main heat exchanger 25 for reheating and is sent out of the main heat exchanger 25 for discharge. The remaining air is cooled and enters the bottom of the lower tower 28, and is separated into high-purity nitrogen and oxygen-rich liquid air through distillation. After passing through the cooler 27, a part of the liquid air at the bottom of the tower is throttled into the dehydrogenation tower condenser 30 as a cold source, and after being vaporized, it returns to the upper tower 32 to continue to participate in distillation, and the remaining air is throttled into the lower tower condenser evaporator 29 at the bottom of the upper tower (wherein the lower tower condenser evaporator 29 acts on the lower tower 28 and the upper tower 32 at the same time, condensing on the lower tower 28 and evaporating on the upper tower 32, and the working principle of the lower tower condenser evaporator 29 is the existing technology, so it will not be described in detail) to exchange heat with nitrogen. After condensation, the nitrogen is used as the reflux liquid of the distillation tower, a part of which is refluxed into the lower tower 28, and a part of which is intercepted and enters the dehydrogenation tower body 1. Ultra-pure product nitrogen is extracted from the bottom of the dehydrogenation tower body 1, and is sent out after being reheated by the main heat exchanger 25; The liquid air evaporates into oxygen-rich steam and continues to participate in distillation in the upper tower 32, and finally obtains low-pressure pure nitrogen at the top of the upper tower 32, and then is converted into liquid nitrogen after condensation in the upper tower condenser 33. A part of it flows back to the upper tower 32 as the upper tower reflux liquid, and the other part is pressurized by the liquid nitrogen pump 34 and enters the top of the lower tower, thereby increasing the liquid nitrogen reflux ratio of the lower tower 28 and improving the nitrogen extraction rate of the lower tower 28. At the same time, the oxygen-rich liquid air in the lower tower 28 is pumped into the upper tower 32 as the cold source of the upper tower condenser 33, and the oxygen-rich liquid air is converted into dirty nitrogen.

[0025] The dirty nitrogen gas is led out from the top of the upper tower condenser 33 to the main heat exchanger 25 for reheating to room temperature and then separated, part of which is used as the regeneration gas of the purification system and the rest is released.

[0026] The pure dry air after removing water, carbon dioxide and some hydrocarbons is sent to the main heat exchanger 25, and heat is exchanged with the reflux low-temperature exhaust gas and the product nitrogen through the main heat exchanger 25. Part of the air is condensed into liquid and the rest is still in gaseous state, and is passed into the bottom of the lower tower 28. The lower tower 28 adopts a structured packing tower to achieve full contact between gas and liquid and material exchange. The top of the lower tower 28 is provided with a lower tower condenser evaporator 29. Light components such as (nitrogen, hydrogen) are not easily condensed and rise to the top of the lower tower 28. Part of the air enters the lower tower 28. The liquid air at the bottom of the lower tower 28 is subcooled by the subcooler 27 to reduce the gasification of the liquid air and then throttled into the lower tower condenser evaporator 29 to reduce the temperature, so that the gas rising from the lower tower 28 can be condensed into liquid and refluxed to the top of the lower tower 28. The reflux liquid condenses the heavy components such as oxygen in the gas rising from the lower tower 28 into liquid and gathers at the bottom of the tower. The light components such as nitrogen and hydrogen are not easily condensed and rise along the tower body and gather at the top of the tower. Since the lower tower condenser evaporator 29 is set at the top of the lower tower 28 The rising gas temperature is higher than the temperature of the lower tower condenser evaporator 29, and then the oxygen-rich liquid air is evaporated into gaseous state and passed into the bottom of the upper tower. The upper tower condenser 33 is set at the top of the upper tower. The oxygen-rich liquid air provided by the lower tower condenser evaporator 29 first enters the bottom of the upper tower 32, and then enters the upper tower condenser 33 through throttling. At this time, the oxygen-rich air rising along the upper tower 32 enters the upper tower 32 and is condensed into liquid by the liquid air and refluxes to the top of the upper tower 32. The reflux liquid condenses the heavy components in the rising gaseous state, such as oxygen, into liquid Accumulate at the bottom of the tower, while light components such as nitrogen and hydrogen that are not easily condensed accumulate at the top of the tower. At this time, a portion of liquid nitrogen is extracted from the reflux liquid of the upper tower 32 and pressurized by a liquid nitrogen pump 34, and passed into the top of the lower tower 28 to increase the reflux liquid of the lower tower. Since the upper and lower towers cannot remove the hydrogen component, the working principles and connection relationships of the main heat exchanger 25, expander 26, subcooler 27, lower tower 28, lower tower condenser evaporator 29, upper tower 32 and upper tower condenser 33 are all prior art, so they will not be described in detail. At this time, a dehydrogenation tower body 1 is added. A dehydrogenation tower condenser 30 is arranged on the upper part of the dehydrogenation tower body 1, and a dehydrogenation tower evaporator 31 is arranged at the bottom. First, part of the liquid nitrogen at the top of the lower tower 28 is introduced into the top of the dehydrogenation tower body 1 as reflux liquid. At the same time, the nitrogen extraction part entering the lower tower condenser evaporator 29 at the top of the lower tower 28 enters the dehydrogenation tower evaporator 31 at the bottom of the dehydrogenation tower body 1. The dehydrogenation tower condenser 30 at the top of the dehydrogenation tower body 1 is introduced into the throttled oxygen-rich liquid air. At this time, the dehydrogenation tower condenser 30 reaches -174°C. The bottom dehydrogenation tower evaporator 31, due to the high temperature of the introduced nitrogen -172°C, is used as a heat source to continuously condense liquid nitrogen. The hydrogen component in the liquid nitrogen and part of the nitrogen component rise along the dehydrogenation tower body 1 and enter the upper tower condenser 33. Since the temperature of the oxygen-rich liquid air is relatively low, the nitrogen component is condensed into a liquid and refluxed to the top of the dehydrogenation tower body 1 as a reflux liquid, while the hydrogen component has a relatively low boiling point and is still in a gaseous state, and is directly discharged from the upper tower condenser 33 at the top of the dehydrogenation tower body 1. In the dehydrogenation tower body 1, nitrogen is a heavy component, and hydrogen is a light component. The nitrogen component is condensed into a liquid by the reflux liquid and accumulates at the bottom of the tower, while the light component cannot be condensed by the reflux liquid due to its relatively low boiling point, so the hydrogen component accumulates at the top of the tower, thereby obtaining ultra-pure nitrogen at the bottom of the dehydrogenation tower body 1, and then it is reheated and extracted through the main heat exchanger 25.

[0027] Therefore, by configuring the dehydrogenation tower body 1, it is not necessary to consider the service life of the adsorbent, and the subsequent maintenance cost is also reduced.

[0028] Embodiment 2 Although the problem of later maintenance costs can be solved in the above embodiment, when the hydrogen content in the rising gas (nitrogen) in the dehydrogenation tower body 1 is different, the rising speed of nitrogen will be different, because the density of hydrogen is much lower than that of nitrogen. When the hydrogen content is high, the average density of the mixed gas decreases. Under the action of gravity, the mixed gas with a smaller density is easier to flow upward, which will also accelerate the rising speed of nitrogen. Just like a hydrogen balloon will rise rapidly in the air, a mixed gas containing a large amount of hydrogen will also flow upward more rapidly in the dehydrogenation tower. At the same time, because gas separation mainly depends on the full contact and interaction between nitrogen and the reflux liquid, when the gas rising speed is accelerated, it means that the contact time between the gas and the reflux liquid is greatly shortened. In a limited time, it is difficult for nitrogen to fully dissolve in the reflux liquid and achieve effective separation, resulting in part of the nitrogen escaping rapidly with the rapidly rising gas flow, which ultimately reduces the efficiency of separating nitrogen. This embodiment is specially invented to solve the above problem.

[0029] See also Figure 2-Figure 9On the basis of the above embodiment, the adopted technical solution includes a dehydrogenation tower body 1 and a plurality of tower plates 2 axially arranged in the dehydrogenation tower body 1, a plurality of riser pipes 3 for allowing rising gas to enter are arranged on the surface of the tower plate 2 close to the top of the dehydrogenation tower body 1, a bubble cap 4 which can move back and forth and rotate along its axial direction is arranged on the top of the riser pipe 3, and a power component which can transmit power to the bubble cap 4 is arranged in the riser pipe 3; The power component includes a driving fan 7 rotatably arranged on the inner circumference of the riser 3, and a driving rod 9 is fixedly connected to the top of the driving fan 7, so that when the driving fan 7 rotates, the driving rod 9 can be prompted to rotate with it, and a blocking driving component is fixedly connected to the top of the bubble cap 4, and a plurality of auxiliary driving plates 12 that can be snapped onto the blocking driving component are arranged on the top of the driving rod 9; A first elastic member 8 is disposed on the top of the riser 3 to enable the bubble cap 4 to return to its original position, wherein the first elastic member 8 is a spring.

[0030] A plurality of air inlets 21 adapted to the riser 3 are provided on the horizontal plane of the tower plate 2 , so that rising gas can enter the riser 3 through the air inlets 21 , and the rising flow of the gas can drive the driving fan 7 to rotate.

[0031] One end of the first elastic member 8 away from the riser 3 is fixedly connected to the first ring plate 14, and one end of the first ring plate 14 away from the first elastic member 8 is rotatably connected to the inner top surface of the bubble 4, so when the bubble 4 rotates, the first elastic member 8 will not hinder the bubble 4.

[0032] One end of the driving rod 9 close to the driving fan 7 is rotatably connected to a fixing plate, and the outer peripheral surface of the fixing plate is fixedly connected to a plurality of fixing columns, one end of which is arranged on the riser 3. By setting the fixing plate, the driving rod 9 can be vertically stabilized on the riser 3. At the same time, when the driving fan 7 rotates, the driving rod 9 will also rotate on the fixing plate. The middle part of the driving rod 9 is rotatably connected to a screw sleeve 16, and the bottom of the screw sleeve 16 is fixedly connected to a plurality of fixing rods 18, one end of which is arranged on the riser 3. By setting the fixing rods 18, the screw sleeve 16 can be fixed on the riser 3, so the rotation of the driving rod 9 will not cause the screw sleeve 16 to rotate with it. The inner top surface of the bubble cap 4 is fixedly connected with an auxiliary movable barrel 15, the bottom of the auxiliary movable barrel 15 is movably connected to the screw sleeve 16, and the bottom of the auxiliary movable barrel 15 protrudes with a protrusion that is clamped on the spiral groove of the screw sleeve 16. Therefore, when the bubble cap 4 rotates, the auxiliary movable barrel 15 will also rotate with it. At the same time, when the auxiliary movable barrel 15 rotates, the setting of the protrusion can prompt the bubble cap 4 to move downward.

[0033] The blocking drive component includes a drive barrel 5 fixedly connected to the top surface of the bubble cap 4, a plurality of drive baffles 10 are evenly fixedly connected to the inner circumference of the drive barrel 5, the top of the drive rod 9 is slidably connected to an auxiliary positioning cylinder 23 along its axial direction, a plurality of limit rods 24 are vertically arranged on the top of the drive rod 9, the auxiliary positioning cylinder 23 is rotatably connected to the bottom of the drive barrel 5 through a bearing, and the top of the drive rod 9 extends into the drive barrel 5, wherein the number of the limit rods 24 is four, and the limit rods 24 and the auxiliary positioning cylinder 23 are slidably connected, so when the drive rod 9 rotates, the setting of the limit rods 24 can prompt the auxiliary positioning cylinder 23 to rotate together.

[0034] An auxiliary circular plate 11 is fixedly connected to the top of the driving rod 9, and a plurality of limiting grooves are evenly opened on the outer circumference of the auxiliary circular plate 11. A plurality of auxiliary driving plates 12 are respectively slidably connected in the corresponding limiting grooves. A second elastic member 13 is fixedly connected to one end of the auxiliary driving plate 12 away from the inner circumference of the driving barrel 5, wherein the second elastic member 13 is a tension spring, and one end of the second elastic member 13 away from the auxiliary driving plate 12 is fixedly connected in the limiting groove; Therefore, when the driving rod 9 rotates, the auxiliary circular plate 11 will also rotate with it. When the auxiliary circular plate 11 rotates, the auxiliary driving plate 12 will move away from the auxiliary circular plate 11 due to the centrifugal force. Therefore, when the auxiliary driving plate 12 is clamped on the driving baffle 10, it will rotate with the driving barrel 5, so that the driving barrel 5 causes the bubble cap 4 to rotate together. When the bubble cap 4 rotates, it will also rotate with the auxiliary moving barrel 15. At the same time, when the auxiliary moving barrel 15 rotates, the setting of the protrusion and the screw sleeve 16 can cause the bubble cap 4 to move downward. When the hydrogen content in the rising gas remains constant, the rotation speed of the driving fan 7 will remain stable. Under this stable working condition, the auxiliary driving plate 12 drives the driving barrel 5 to rotate through the driving baffle 10. Since the driving baffle 10 adopts an inclined design, during the continuous downward displacement of the driving barrel 5, the contact state between the driving baffle 10 and the auxiliary driving plate 12 will change until the two are out of contact. At this time, the elastic potential energy of the first elastic member 8 begins to play a role. Under the action of the elastic restoring force of the first elastic member 8, the bubble cap 4 pushes the driving barrel 5 together with the driving baffle 10 to move upward until the driving baffle 10 re-establishes contact with the next auxiliary driving plate 12. After that, the system will repeat the above series of actions to form a periodic dynamic cycle process to maintain the stable operation of the system and the realization of specific functions. When the hydrogen content in the rising airflow decreases, the rotation speed of the driving fan 7 decreases accordingly. The decrease in the rotation speed of the driving fan 7 causes the centrifugal force on the auxiliary driving plate 12 to decrease. At this time, under the elastic restoring force of the second elastic member 13, the auxiliary driving plate 12 is pulled back. As the auxiliary driving plate 12 is pulled back, its blocking effect on the driving barrel 5 is eliminated, and the first elastic member 8 releases its own elastic potential energy to generate an upward driving force, prompting the driving barrel 5 to move upward together with the bubble 4. Through such a mechanical linkage mechanism, the vertical position of the bubble 4 can be accurately controlled according to the dynamic changes of the hydrogen content in the rising airflow.

[0035] The rising gas is nitrogen, but nitrogen contains hydrogen. When the content of hydrogen in nitrogen is different, the rising speed of nitrogen will be different, because the density of hydrogen is much lower than that of nitrogen. When the hydrogen content is high, the average density of the mixed gas decreases. Under the action of gravity, the mixed gas with a smaller density is easier to flow upward, which will also accelerate the rising speed of nitrogen. Just like a hydrogen balloon will rise quickly in the air, a mixed gas containing a large amount of hydrogen will also flow upward more quickly in the dehydrogenation tower. At the same time, because gas separation mainly depends on the full contact and interaction between nitrogen and reflux liquid, when the gas rising speed is accelerated, it means that the contact time between the gas and the reflux liquid is greatly shortened. In a limited time, it is difficult for nitrogen to fully dissolve in the reflux liquid and achieve effective separation, resulting in part of the nitrogen escaping quickly with the rapidly rising gas flow, which ultimately reduces the efficiency of separating nitrogen. When the hydrogen content in nitrogen is high, the rising speed of nitrogen is accelerated, and the increase in gas flow rate further increases the speed of the driving fan 7. As the speed of the driving fan 7 increases, the auxiliary driving plate 12 is thrown out due to the increase in centrifugal force. When the auxiliary driving plate 12 is clamped on the driving baffle 10, it will drive the bubble cap 4 to rotate together. Due to the special design of the screw sleeve 16, the bubble cap 4 will move downward when it rotates. In this way, the mixed gas entering the riser 3 from the air inlet 21 and the path discharged from the bottom of the bubble cap 4 are increased, and the bubble rising path is also correspondingly longer, which greatly enhances the effect of nitrogen being separated by the reflux liquid.

[0036] Embodiment 3 In the above embodiment, the problem of concentration fluctuation of hydrogen in nitrogen is successfully solved. As a key parameter, hydrogen concentration has a significant influence on the rising flow rate of nitrogen, and thus affects the mass transfer and separation efficiency of nitrogen in the process of contacting with the reflux liquid. By optimizing the structural design, the movement distance of nitrogen in the reflux liquid is effectively regulated, and the mass transfer and separation efficiency of nitrogen in the reflux liquid is greatly improved. However, in the dehydrogenation tower body 1, there is a balance between gas and liquid. Factors such as the temperature and composition of the gas phase will affect the temperature of the reflux liquid. The liquid ammonia far away from the tower plate is closer to the gas phase and is more easily affected by the gas phase. It exchanges heat and substances with the gas phase, thereby affecting its temperature. The reflux liquid close to the tower plate 2 mainly interacts with the tower plate 2 and a small amount of liquid above it, and is less directly affected by the gas phase. The temperature change mechanism is different from that of the liquid ammonia far away from the tower plate, and the temperatures of the two will be different. Therefore, this phenomenon will greatly affect the conversion efficiency of the reflux liquid to nitrogen. This embodiment is specially invented to solve the above problem.

[0037] See also Figure 2-Figure 9 On the basis of the above-mentioned embodiment, the adopted technical solution includes that the bottom of the outer peripheral surface of the bubble cap 4 is rotatably connected with an auxiliary connecting cylinder 19, the outer peripheral surface of the auxiliary connecting cylinder 19 is provided with a sliding mounting cylinder 20 which can slide along its axial direction, and the outer peripheral surface of the sliding mounting cylinder 20 is evenly fixedly connected with a plurality of driving plates 6, so when the driving plate 6 is subjected to external force, it will rotate on the auxiliary connecting cylinder 19 with the sliding mounting cylinder 20.

[0038] The surface of the sliding installation cylinder 20 away from the tower plate 2 is fixedly connected with a floating plate 17 .

[0039] One side of the driving plate 6 is an inclined surface. Therefore, when the flowing reflux fluid impacts the multiple driving plates 6, the inclined surface can disperse the force. Figure 6From the perspective of the driving plate 6, the sliding mounting cylinder 20 will be driven to rotate in the clockwise direction. At the same time, due to the setting of the inclined surface, the driving plate 6 will push the liquid at the bottom of the upper surface of the tower plate 2 upward while the driving plate 6 rotates, thereby destroying the temperature stratification phenomenon of the reflux liquid on the tower plate 2 (because the reflux liquid will have a certain flow and mixing on the tower plate, but this flow and mixing may not necessarily make the temperature of the liquid nitrogen layer completely uniform. The part close to the tower plate has a relatively slow flow speed and a relatively weak mixing degree due to factors such as the friction between the liquid and the tower plate surface. The reflux liquid far away from the tower plate is subject to less friction resistance, and will have relatively strong convection and mixing, and the heat exchange with the gas phase is relatively more sufficient, which causes its temperature to be different from that of the liquid ammonia close to the tower plate. At the same time, in the dehydrogenation tower body 1, there is a balance between gas and liquid. Factors such as the temperature and composition of the gas phase will affect the temperature of the reflux liquid. The liquid ammonia far away from the tower plate is closer to the gas phase and is more easily affected by the gas phase, and exchanges heat and substances with the gas phase, thereby Affects its temperature. The reflux liquid near the tower plate 2 mainly interacts with the tower plate 2 and a small amount of liquid above it, and is less directly affected by the gas phase. The temperature change mechanism is different from that of the liquid ammonia far away from the tower plate, and the temperatures of the two will be different. Therefore, this phenomenon will greatly affect the conversion efficiency of the reflux liquid to nitrogen). When the driving plate 6 rotates, the reflux liquid can produce additional turbulence. This turbulence will form complex eddies and circulations in the liquid, further enhancing the energy exchange between different layers of the liquid. The originally stratified liquid is difficult to maintain a stable stratified state under this strong turbulence, and the temperature stratification phenomenon will be significantly destroyed. At the same time, the mechanical energy generated by the stirring of the driving plate 6 will intensify the mixing between the various parts of the reflux liquid. The reflux liquid near the tower plate 2 with a lower temperature and the reflux liquid near the nitrogen with a higher temperature will be forced to mix, and the temperature difference will gradually decrease during the mixing process, thereby effectively destroying the stratification phenomenon formed by the liquid ammonia due to different temperatures, thereby greatly increasing the conversion efficiency between the reflux liquid and nitrogen.

[0040] The outer circumference of the auxiliary connecting tube 19 is evenly provided with a plurality of slide grooves 22, and the inner circumference of the sliding mounting tube 20 is protruded with a plurality of convex plates, which are slidably connected in the corresponding slide grooves 22, respectively, wherein the height of the lower surface of the floating plate 17 is exactly flush with the upper surface of the reflux liquid. Therefore, through the setting of the floating plate 17, the upper and lower positions of the driving plate 6 will not change when the bubble cap 4 moves downward.

[0041] When the driving plate 6 rotates, the rotation of the driving plate 6 will trigger a series of physical phenomena. On the one hand, it will extend the movement trajectory of the bubbles in the reflux liquid, that is, by increasing the travel path of the bubbles, the interaction between gas and liquid will be strengthened; on the other hand, the rotation of the driving plate 6 will produce a shearing and crushing effect on the rising bubbles, breaking the large bubbles into multiple small bubbles, greatly increasing the contact area between nitrogen and reflux liquid. This series of action mechanisms can significantly improve the mass transfer efficiency between the liquid phase and the gas phase, thereby greatly improving the conversion efficiency between the liquid and nitrogen.

[0042] In summary, when the device for preparing ultrapure nitrogen is used, the rising gas enters the riser 3 from the gas inlet 21. In the riser 3, the gas maintains a certain flow rate and pressure to maintain its rising power. Subsequently, the gas enters the reflux liquid inside the bubble cap 4 in the form of bubbles. In the bubble cap 4, the gas and liquid begin to make initial contact and a mass transfer process occurs. Then, the bubbles formed by the gas overflow from the bottom of the bubble cap 4 and pass through the liquid layer on the tower plate 2. In this process, the bubbles are fully in contact with the reflux liquid and heat exchange occurs, that is, a gas-liquid heat transfer process. Finally, the bubbles that pass through the reflux liquid return to the gas phase space of the dehydrogenation tower body 1 again and continue to participate in the gas-liquid separation and conversion process in the tower. At the same time, the reflux liquid will also come into contact with the hydrogen in the rising gas. Although the temperature of the reflux liquid does not reach the condition for liquefying the hydrogen, the reflux liquid can still promote the adsorption of some hydrogen atoms. In this process, the reflux liquid accumulated at the bottom of the dehydrogenation tower body 1 continues to evaporate, and the rising gas is continuously treated by the reflux liquid to achieve continuous removal of hydrogen until the nitrogen purity reaches the preset standard.

[0043] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0044] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An apparatus for preparing ultrapure nitrogen, comprising a lower tower (28), an upper tower (32), a dehydrogenation tower body (1), and a plurality of tower plates (2) axially arranged in the dehydrogenation tower body (1), characterized in that: A plurality of riser pipes (3) are arranged on the surface of the tower plate (2) close to the top of the dehydrogenation tower body (1) so as to allow rising gas to enter, a bubble cap (4) is arranged on the top of the riser pipe (3) and is capable of moving back and forth and rotating along its axial direction, and a power component capable of transmitting power to the bubble cap (4) is arranged inside the riser pipe (3); The power component comprises a driving fan (7) rotatably arranged on the inner circumference of the riser (3), the top of the driving fan (7) being fixedly connected to a driving rod (9), the top of the bubble cap (4) being fixedly connected to a blocking driving component, the top of the driving rod (9) being provided with a plurality of auxiliary driving plates (12) capable of being snapped onto the blocking driving component; A first elastic member (8) capable of causing the bubble cap (4) to return to its original position is arranged at the top of the air riser (3).

2. The device for preparing ultrapure nitrogen according to claim 1, characterized in that: A plurality of air inlets (21) adapted to the air riser (3) are provided on the horizontal surface of the tower plate (2).

3. The device for preparing ultrapure nitrogen according to claim 2, characterized in that: One end of the first elastic member (8) away from the riser (3) is fixedly connected to a first ring plate (14), and one end of the first ring plate (14) away from the first elastic member (8) is rotatably connected to the inner top surface of the bubble cap (4).

4. The device for preparing ultrapure nitrogen according to claim 3, characterized in that: The end of the driving rod (9) close to the driving fan (7) is rotatably connected to a fixing plate, and the outer peripheral surface of the fixing plate is fixedly connected to a plurality of fixing columns, one end of which is arranged on the riser (3); the middle part of the driving rod (9) is rotatably connected to a screw sleeve (16), and the bottom of the screw sleeve (16) is fixedly connected to a plurality of fixing rods (18) one end of which is arranged on the riser (3); The inner top surface of the bubble cap (4) is fixedly connected to an auxiliary movable barrel (15), the bottom of the auxiliary movable barrel (15) is movably connected to a screw sleeve (16), and a protrusion protrudes from the bottom of the auxiliary movable barrel (15) and is clamped on a spiral groove of the screw sleeve (16).

5. The device for preparing ultrapure nitrogen according to claim 4, characterized in that: The blocking driving component comprises a driving barrel (5) fixedly connected to the top surface of the bubble cap (4); a plurality of driving baffles (10) are evenly fixedly connected to the inner circumference of the driving barrel (5); the top of the driving rod (9) is slidably connected to an auxiliary positioning barrel (23) along its axial direction; a plurality of limiting rods (24) are vertically arranged on the top of the driving rod (9); the auxiliary positioning barrel (23) is rotatably connected to the bottom of the driving barrel (5); and the top of the driving rod (9) extends into the driving barrel (5).

6. The device for preparing ultrapure nitrogen according to claim 5, characterized in that: An auxiliary circular plate (11) is fixedly connected to the top of the driving rod (9); a plurality of limit grooves are evenly formed on the outer circumference of the auxiliary circular plate (11); a plurality of auxiliary driving plates (12) are slidably connected in the corresponding limit grooves; an end of the auxiliary driving plate (12) away from the inner circumference of the driving barrel (5) is fixedly connected to a second elastic member (13); an end of the second elastic member (13) away from the auxiliary driving plate (12) is fixedly connected in the limit groove.

7. The device for preparing ultrapure nitrogen according to claim 6, characterized in that: The bottom of the outer peripheral surface of the bubble cap (4) is rotatably connected to an auxiliary connecting cylinder (19), the outer peripheral surface of the auxiliary connecting cylinder (19) is provided with a sliding mounting cylinder (20) that can slide along its axial direction, and the outer peripheral surface of the sliding mounting cylinder (20) is evenly fixedly connected to a plurality of driving plates (6).

8. The device for preparing ultrapure nitrogen according to claim 7, characterized in that: A floating plate (17) is fixedly connected to a surface of the sliding installation cylinder (20) away from the tower plate (2).

9. The device for preparing ultrapure nitrogen according to claim 8, characterized in that: One side of the driving plate (6) has an outer surface which is an inclined surface.

10. The device for preparing ultrapure nitrogen according to claim 9, characterized in that: The outer circumference of the auxiliary connection cylinder (19) is evenly provided with a plurality of slide grooves (22), and the inner circumference of the sliding installation cylinder (20) is provided with a plurality of convex plates, and the plurality of convex plates are respectively slidably connected in the corresponding slide grooves (22).

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