Air separation equipment

Abstract

The present invention relates to the technical field of air separation, and specifically discloses an air separation device, including an air filter, an air compressor unit, a precooling system, a purification system, a fractionation tower, a liquid oxygen storage system, a liquid nitrogen storage system and a liquid argon storage system, wherein the precooling system includes a first cooling tower, a spray chamber is arranged in the first cooling tower, a first spray assembly and a second spray assembly are arranged in the spray chamber, the first spray assembly is connected to a first water supply pipeline, the second spray assembly is connected to a second water supply pipeline, the bottom of the spray chamber is connected to a circulation pipeline, the circulation pipeline is connected to a circulation water pool, the first water supply pipeline and the second water supply pipeline are both connected to the circulation water pool, and a cooling mechanism for cooling the cooling water inside the pipeline is installed on the second water supply pipeline. An air separation device of the present invention can enable the precooling system to improve the cooling effect of high-temperature air, reduce the use of cooling water, and reduce production costs.

Description

Technical Field

[0001] The present invention relates to the technical field of air separation, and in particular to an air separation device. Background Art

[0002] In the prior art, air separation is referred to as air separation, which refers to the process of separating oxygen and nitrogen from the air, or extracting rare gases such as helium and argon at the same time, by using the different physical properties of the components in the air, using methods such as deep freezing, adsorption, and membrane separation. The air separation process is generally as follows: first, the air in the external environment is initially filtered through a filter to remove large impurities; second, it is compressed through an air compressor to obtain air at a higher pressure; then, the air is allowed to enter a cooling tower for pre-cooling to obtain air at a lower temperature; then, the air is passed through a purification system to remove moisture and other gas impurities in the air; finally, the high-pressure, pure air is sent to a distillation tower for separation to obtain liquid oxygen, liquid nitrogen, and liquid argon. At present, cooling towers usually use spraying to cool the air. During the spraying, the spray water is only used for initial cooling in a circulating water pool and then repeatedly sprayed. The cooling effect on high-temperature air is poor. Therefore, in order to cool the air to the required temperature, multiple spray pipes need to be set up to use a large amount of cooling water for cooling, which increases the use of cooling water, wastes a lot of water resources, and increases production costs. Summary of the invention

[0003] The present invention aims to solve at least one of the above-mentioned technical problems and provide an air separation device, which can improve the cooling effect of the precooling system on high-temperature air, reduce the use of cooling water, and reduce production costs.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present invention is: an air separation device, comprising an air filter, an air compressor unit, a precooling system, a purification system, a fractionation tower, a liquid oxygen storage system, a liquid nitrogen storage system and a liquid argon storage system, the precooling system comprising a first cooling tower, the bottom and top of the first cooling tower are respectively provided with an air inlet and an exhaust port, the air inlet is connected to a first gas pipeline, and the exhaust port is connected to a second gas pipeline, a spray chamber is provided in the first cooling tower, a first spray assembly and a second spray assembly are sequentially arranged in the spray chamber from bottom to top, the first spray assembly and the second spray assembly are arranged between the air inlet and the exhaust port to spray cool the air entering the spray chamber, the first spray assembly is connected to a first water supply pipeline, the second spray assembly is connected to a second water supply pipeline, the bottom of the spray chamber is connected to a circulation pipeline, the circulation pipeline is connected to a circulation pool, the first water supply pipeline and the second water supply pipeline are both connected to the circulation water pool, wherein a cooling mechanism for cooling the cooling water inside the pipeline is installed on the second water supply pipeline.

[0005] Preferably, the second water supply pipeline is also provided with a second cooling tower for preliminarily cooling the cooling water, a cooling chamber is provided inside the second cooling tower, a third spray assembly is provided at the upper part of the cooling chamber, the third spray assembly is connected with the circulating water pool through a connecting pipe, the second water supply pipeline is connected with the bottom of the cooling chamber, and further includes a nitrogen delivery pipeline, the nitrogen delivery pipeline is connected with the middle part of the cooling chamber so as to introduce nitrogen into the cooling chamber for cooling the cooling water, and a gas outlet for discharging nitrogen is provided at the top of the second cooling tower.

[0006] Preferably, a first water storage cavity is provided at the bottom of the cooling chamber, a first liquid level detection device is provided in the first water storage cavity, a first control valve for controlling the on-off of the pipeline is provided on the connecting pipeline, the first liquid level detection device is connected to the first control valve, and controls the opening and closing of the first control valve according to the detected liquid level signal.

[0007] Preferably, a second water storage cavity is provided at the bottom of the spray chamber, the circulation pipeline is connected to the second water storage cavity, and a second drainage pipeline is also provided at the bottom of the second water storage cavity.

[0008] Preferably, a second control valve is provided on the second drainage pipeline, a first pump body is provided on both the first water supply pipeline and the second water supply pipeline, a pressure detection device is provided on the second gas pipeline, and the pressure detection device is connected to a controller. The controller can control the operation of the second control valve and the first pump body respectively according to the pressure signal detected by the pressure detection device.

[0009] Preferably, a second liquid level detection device is installed in the second water storage cavity, and a third control valve for controlling the on-off of the circulation pipeline is provided on the circulation pipeline. The second liquid level detection device is connected to the third control valve and controls the opening and closing of the third control valve according to the detected liquid level signal.

[0010] Preferably, it further comprises a nitrogen circulation system, the nitrogen circulation system comprising a heat exchanger, a circulating nitrogen compressor, a high-temperature expander, a low-temperature expander, a first booster aftercooler, a second booster aftercooler, a first connecting pipeline, a second connecting pipeline and a third connecting pipeline, the bottom chamber of the fractionation tower is provided with a connected gas outlet and a gas return port, the top chamber of the fractionation tower is provided with a reflux port, the high-temperature expander has a high-temperature expansion end and a high-temperature boosting end, and the low-temperature expander has a low-temperature expansion end and a low-temperature boosting end;

[0011] One end of the first connecting pipeline is connected to the air outlet, and the other end passes through the heat exchanger, the circulating nitrogen compressor, the high-temperature booster end, the first booster aftercooler, the low-temperature booster end, the second booster aftercooler in sequence, and then passes through the heat exchanger to be connected to the return air port;

[0012] One end of the second connecting pipeline is connected to the first connecting pipeline between the heat exchanger and the return air port, and the other end is connected to the first connecting pipeline between the heat exchanger and the circulating nitrogen compressor after passing through the low-temperature expansion end;

[0013] One end of the third connecting pipeline is connected to the first connecting pipeline between the circulating nitrogen compressor and the high-temperature boost end, and the other end passes through the heat exchanger and the high-temperature expansion end in sequence, and then passes through the heat exchanger to be connected to the first connecting pipeline between the heat exchanger and the circulating nitrogen compressor.

[0014] Preferably, it also includes a temperature regulating pipeline, one end of which is connected to the first connecting pipeline between the second connecting pipeline and the return air port, and the other end is connected to the second connecting pipeline, a temperature detection device is provided on the second connecting pipeline, and a first regulating valve connected to the temperature detection device is provided on the temperature regulating pipeline, and the temperature detection device controls the opening of the first regulating valve by detecting a temperature signal.

[0015] Preferably, a gas-liquid separation tank is arranged on the second connecting pipeline between the low-temperature expansion end and the heat exchanger, the bottom of the gas-liquid separation tank is connected to the reflux port through the reflux pipeline, the second connecting pipeline is respectively connected to the middle and top of the gas-liquid separation tank, a third liquid level detection device is arranged in the gas-liquid separation tank, and a second regulating valve connected to the third liquid level detection device is arranged on the reflux pipeline, and the third liquid level detection device controls the opening and closing of the second regulating valve by detecting the liquid level signal.

[0016] Preferably, the top of the fractionation tower is connected to the second cooling tower through a nitrogen delivery pipeline so as to introduce nitrogen into the second cooling tower.

[0017] The beneficial effect is: compared with the prior art, an air separation device of the present invention passes high-temperature air from the air inlet into the spray chamber of the first cooling tower, cools it by spraying, and then discharges it through the exhaust port, thereby achieving pre-cooling of the air. When cooling, the air is firstly sprayed and cooled by normal temperature cooling water through the first spray component, and then the cooling water on the second water supply pipeline is cooled and cooled into low-temperature cooling water through the cooling mechanism, and then the air is further cooled and cooled by the second spray component. The spray cooling method combining normal temperature and low-temperature cooling water is adopted, which improves the cooling effect of high-temperature air. When achieving the same cooling effect, the number of spraying is reduced, thereby reducing the amount of cooling water used and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 A schematic diagram of the connection structure of an air separation device of the present invention;

[0020] Figure 2 for Figure 1 A schematic diagram of the structure of the precooling system;

[0021] Figure 3 for Figure 2 A schematic diagram of the structure of the first cooling tower;

[0022] Figure 4 for Figure 2 A schematic diagram of the structure of the second cooling tower;

[0023] Figure 5 for Figure 1 Schematic diagram of the nitrogen circulation system in FIG. DETAILED DESCRIPTION

[0024] 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.

[0025] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may be a central component at the same time. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component at the same time. When a component is referred to as being "set in the middle", it does not only mean being set in the middle, as long as it is not set at both ends within the range defined by the middle. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] like Figures 1 to 4As shown, an air separation device includes an air filter 1, an air compressor unit 2, a precooling system 3, a purification system 4, a fractionating tower 5, a liquid oxygen storage system 6, a liquid nitrogen storage system 7 and a liquid argon storage system 8. The precooling system 3 includes a first cooling tower 9. The bottom and top of the first cooling tower 9 are respectively provided with an air inlet and an exhaust port. The air inlet is connected to a first gas pipeline 10 to pass the high-temperature and high-pressure air compressed by the air compressor unit 2 into the first cooling tower 9. The exhaust port is connected to a second gas pipeline 11, and the cooled air is output to the purification system 4. A spray chamber is provided in the first cooling tower 9. The first spray assembly 12 and the second spray assembly 13 are sequentially arranged in the spray chamber from bottom to top. The first spray assembly 12 and the second spray assembly 13 are arranged at the air inlet and the exhaust port. In order to spray and cool the air introduced into the spray chamber, the first spray assembly 12 is connected to the first water supply pipeline 14, and the second spray assembly 13 is connected to the second water supply pipeline 15. The cooling water is respectively transported to the first spray assembly 12 and the second spray assembly 13 through the first water supply pipeline 14 and the second water supply pipeline 15. Specifically, the first spray assembly 12 and the second spray assembly 13 both include a spray pipe fixedly installed in the spray chamber, and a plurality of nozzles are arranged on the spray pipe. The bottom of the spray chamber is connected to a circulation pipeline 16, and the circulation pipeline 16 is connected to a circulation pool 17. The first water supply pipeline 14 and the second water supply pipeline 15 are both connected to the circulation pool 17, wherein the second water supply pipeline 15 is installed with a cooling mechanism 18 for cooling the cooling water inside the pipeline. Specifically, the cooling mechanism 18 can adopt a chiller commonly used in the current air separation system.

[0028] In the process of air separation, the atmosphere is filtered by the air filter 1 and compressed by the air compressor unit 2 to become high-temperature and high-pressure air. The high-temperature air is passed into the spray chamber of the first cooling tower 9 from the air inlet, and is sprayed and cooled by the first spray component 12 and the second spray component 13 in turn. Then, it is transported to the purification system 4 through the exhaust port for drying and impurity removal, and then fractionated by the fractionation tower 5. Finally, the fractionated liquid oxygen, liquid nitrogen and liquid argon are stored in the liquid oxygen storage system 6, the liquid nitrogen storage system 7 and the liquid argon storage system 8 respectively. During cooling, the air is firstly sprayed and cooled by the first spray assembly 12 using cooling water at room temperature, and then the cooling water on the second water supply pipeline 15 is cooled and cooled by the cooling mechanism 18 to become low-temperature cooling water, and then the air is further cooled by the second spray assembly 13. By adopting a spray cooling method combining normal temperature and low-temperature cooling water, the cooling effect of high-temperature air is improved. When the same cooling effect is achieved, the number of spraying is reduced, thereby reducing the amount of cooling water and reducing production costs. At the same time, the cooling water after spraying flows into the circulating water pool 17 through the circulating pipeline 16 at the bottom of the cooling chamber for cooling, and can continue to be passed into the first water supply pipeline 14 and the second water supply pipeline 15 for recycling, so as to achieve the purpose of circulating water.

[0029] In one preferred embodiment, a second cooling tower 19 for preliminarily cooling the cooling water may be provided on the second water supply pipeline 15. After the cooling water is preliminarily cooled by the second cooling tower 19, it is further cooled by the cooling mechanism 18, which can further improve the cooling effect of the cooling water.

[0030] Specifically, a cooling chamber may be provided inside the second cooling tower 19, a third spray assembly 20 is provided at the upper part of the cooling chamber, the third spray assembly 20 is connected to the circulating water pool 17 through a connecting pipe 24, and the second water supply pipeline 15 is connected to the bottom of the cooling chamber, wherein a nitrogen delivery pipeline 21 is also included, the nitrogen delivery pipeline 21 is connected to the middle part of the cooling chamber, so as to introduce nitrogen into the cooling chamber for cooling the cooling water, and a gas outlet for discharging nitrogen is provided at the top of the second cooling tower 19. Specifically, the third spray assembly 20 also includes a spray pipeline and a gas outlet provided in the spray pipeline. The plurality of nozzles on the cooling chamber are fixedly installed on the top of the cooling chamber and connected with the connecting pipe 24. After the nitrogen is introduced into the cooling chamber, the nitrogen flows upward. By setting the spray pipe, the cooling water can be sprayed from the top of the cooling chamber by spraying, and after being fully contacted and cooled with the nitrogen flowing upward, it flows into the second water supply pipeline 15. The cooling water and the nitrogen can be fully contacted by spraying, thereby improving the cooling effect of the nitrogen on the cooling water. After the nitrogen cools the cooling water, it can be discharged through the gas outlet at the top of the second cooling tower 19. Specifically, the nitrogen in this embodiment includes not only clean nitrogen but also dirty nitrogen.

[0031] Furthermore, a first water storage cavity 22 may be provided at the bottom of the cooling chamber, and the cooled cooling water may be stored in the first water storage cavity 22. An overflow pipe may be provided at the top of the first water storage cavity 22. When the cooling water in the first water storage cavity 22 exceeds the set storage capacity, it may be directly discharged into the ditch through the overflow pipe.

[0032] Furthermore, a first liquid level detection device 23 can be arranged in the first water storage cavity 22, and a first control valve 25 for controlling the on-off of the pipeline is arranged on the connecting pipe 24. The first liquid level detection device 23 is connected to the first control valve 25, and controls the opening and closing of the first control valve 25 according to the detected liquid level signal. Specifically, when the first liquid level detection device 23 detects that the liquid level of cooling water in the water storage cavity exceeds the set liquid level, the first liquid level detection device 23 controls the first control valve 25 to close, thereby stopping the water supply to the second cooling tower 19.

[0033] More preferably, the bottom of the first water storage cavity 22 can be connected to a first drainage pipe. Specifically, a drain port is provided at the bottom of the first water storage cavity 22, the first drainage pipe is connected to the drain port, and a valve body for controlling its pipe channel is provided on the first drainage pipe. By providing the first drainage pipe, when the interior of the second cooling tower 19 is cleaned, it is convenient to discharge the cleaning waste water and debris sediment.

[0034] In a more preferred embodiment, a second water storage cavity 26 can be provided at the bottom of the spray chamber, and the circulation pipeline 16 is connected to the second water storage cavity 26. The cooling water after spray cooling of the high-temperature air is collected through the second water storage cavity 26, and then discharged into the circulating water pool 17 through the circulation pipeline 16. A second drainage pipeline 27 is also provided at the bottom of the second water storage cavity 26. By providing the second drainage pipeline 27, when the interior of the first cooling tower 9 is cleaned, the discharge of cleaning waste water and debris sediment is facilitated.

[0035] Furthermore, a second control valve 28 may be provided on the second drainage pipeline 27, and the on-off of the second drainage pipeline may be controlled by the second control valve 28. A first pump body 29 is provided on both the first water supply pipeline 14 and the second water supply pipeline 15, and the first pump body 29 provides power so that the cooling water in the first water supply pipeline 14 and the second water supply pipeline 15 is respectively delivered to the first spray assembly 12 and the second spray assembly 13. A pressure detection device 30 is provided on the second gas transmission pipeline 11, and the pressure detection device 30 is connected to a controller 31. The controller 31 detects the pressure of the first gas transmission pipeline 11 and detects the pressure of the second gas transmission pipeline 11. The pressure signal detected by the force detection device 30 can control the operation of the second control valve 28 and the first pump body 29 respectively. Since the cooling water needs to be transported through the air pressure in the circulation pipeline 16, when the air pressure is low, it will affect the transportation of cooling water. Therefore, when the pressure detection device 30 detects that the air pressure in the second output pipeline is low, the first pump body 29 is controlled to stop working, thereby stopping the transportation of cooling water to the first cooling tower 9, and the second control valve 28 is controlled to open to discharge the cooling water in the second water storage cavity 26.

[0036] Furthermore, a spare pipeline can be connected in parallel to the side of the first pump body 29, and a second pump body is arranged on the spare pipeline. When the first pump body 29 is not faulty, cooling water is transported through the first pump body 29. When the first pump body 29 fails, the power for transporting cooling water is provided by the second pump body, thereby ensuring normal production.

[0037] Furthermore, a second liquid level detection device 32 may be installed in the second water storage cavity 26, and a third control valve 33 for controlling the on-off of the circulation pipeline 16 is provided. The second liquid level detection device 32 is connected to the third control valve 33, and the opening and closing of the third control valve 33 are controlled according to the detected liquid level signal. Specifically, when the second liquid level detection device 32 detects that the liquid level in the second water storage cavity 26 exceeds the set value, the third control valve 33 is controlled to open, thereby discharging the cooling water in the second water storage cavity 26; when the second liquid level detection device 32 detects that the liquid level in the second water storage cavity 26 is lower than the set value, the third control valve 33 is controlled to close.

[0038] like Figure 1 and Figure 5 As shown, the air separation device in this embodiment may also include a nitrogen circulation system 54, the nitrogen circulation system 54 includes a heat exchanger 34, a circulating nitrogen compressor 35, a high-temperature expander 36, a low-temperature expander 37, a first booster aftercooler 38, a second booster aftercooler 39, a first connecting pipeline 40, a second connecting pipeline 41 and a third connecting pipeline 42, the bottom chamber of the fractionation tower 5 is provided with a connected gas outlet and a gas return port, and the top chamber of the fractionation tower 5 is provided with a reflux port. The fractionation tower 5 in this embodiment is an existing structure, and will not be described in detail. It can be used to fractionate the purified air to separate oxygen, nitrogen and argon, etc. The high-temperature expander 36 and the low-temperature expander 37 are both turbine expanders, the high-temperature expander 36 has a high-temperature expansion end 43 and a high-temperature boosting end 44, and the low-temperature expander 37 has a low-temperature expansion end 45 and a low-temperature boosting end 46;

[0039] Among them, one end of the first connecting pipeline 40 is connected to the gas outlet, and the other end passes through the heat exchanger 34, the circulating nitrogen compressor 35, the high-temperature boost end 44, the first booster aftercooler 38, the low-temperature boost end 46, the second booster aftercooler 39 in sequence, and then passes through the heat exchanger 34 again, and is connected to the return port, so that the nitrogen in the fractionation tower 5 flows out from the gas outlet, passes through the first connecting pipeline 40, and then flows back into the fractionation tower 5 through the return port to form a gas loop;

[0040] One end of the second connecting pipeline 41 is connected to the first connecting pipeline 40 between the heat exchanger 34 and the return air port, and the other end is connected to the first connecting pipeline 40 between the heat exchanger 34 and the circulating nitrogen compressor 35 after passing through the low-temperature expansion end 45;

[0041] One end of the third connecting pipeline 42 is connected to the first connecting pipeline 40 between the circulating nitrogen compressor 35 and the high-temperature boost end 44, and the other end passes through the heat exchanger 34 and the high-temperature expansion end 43 in sequence, and then passes through the heat exchanger 34 to be connected to the first connecting pipeline 40 between the heat exchanger 34 and the circulating nitrogen compressor 35.

[0042] During the nitrogen circulation process, the low-temperature nitrogen separated from the fractionation tower 5 releases coldness in the heat exchanger 34 through the first connecting pipeline 40, and the temperature rises. Then, it is compressed by the circulating nitrogen compressor 35, so that the pressure increases and the temperature rises. Then, it is divided into two routes for transportation: one of the nitrogen routes continues to be transported along the first connecting pipeline 40, and is successively preliminarily pressurized at the high-temperature boosting end, preliminarily cooled by the first booster aftercooler 38, further pressurized at the low-temperature boosting end, and further cooled by the second booster aftercooler 39 to become high-pressure nitrogen. The high-pressure nitrogen passes through the heat exchanger 34 again for absorption. After the temperature of the collected cold is lowered, a part of it flows back to the distillation tower 5 from the return port through the first connecting pipeline 40, and the other part flows into the second connecting pipeline 41, expands through the low-temperature expansion end 45 to store the cold, and then releases the cold through the heat exchanger 34, the temperature rises and flows to the first connecting pipeline 40; another nitrogen flows into the third connecting pipeline 42, the temperature drops after absorbing the cold through the heat exchanger 34, and then expands through the high-temperature expansion end 43 to store the cold, and then releases the cold through the heat exchanger 34, the temperature rises, and finally flows to the first connecting pipeline 40. After the nitrogen is expanded through the high-temperature expansion end 43 and the low-temperature expansion end 45, the nitrogen obtains cold energy, and the cold energy in the nitrogen is released through the heat exchanger 34 to obtain the cold energy required in the air separation process. During use, the cold energy can be obtained by connecting other pipelines requiring cold energy in the air equipment to the heat exchanger 34. The pipeline is reasonably arranged, and the nitrogen in the air separation process is fully utilized. The nitrogen can be recycled and the production cost is reduced. At the same time, the nitrogen is pressurized twice by the high-temperature boosting end and the low-temperature boosting end, so that higher pressure nitrogen can be obtained to prepare for the subsequent high-pressure expansion to produce excess cold energy.

[0043] In a more preferred embodiment, a temperature regulating pipeline 47 may also be included, one end of which is connected to the first connecting pipeline 40 between the second connecting pipeline 41 and the return air port, and the other end is connected to the second connecting pipeline 41, so as to adjust the temperature of the nitrogen in the second connecting pipeline 41. Specifically, after the first connecting pipeline 40 releases heat through the heat exchanger 34, a part of it continues to flow into the first connecting pipeline 40, and the other part flows into the second connecting pipeline 41. The temperature of the nitrogen flowing into the first connecting pipeline 40 is lower than the temperature of the nitrogen in the second connecting pipeline 41. The nitrogen in the first connecting pipeline 40 with a lower temperature is transported to the second connecting pipeline 41 through the temperature regulating pipeline 47, thereby achieving the adjustment of the temperature of the nitrogen in the second connecting pipeline 41. Specifically, a temperature detection device 48 is provided on the second connecting pipeline 41, and a first regulating valve 49 connected to the temperature detection device 48 is provided on the temperature regulating pipeline 47. The temperature detection device 48 controls the opening of the first regulating valve 49 by detecting a temperature signal. The temperature detection device 48 can detect the nitrogen temperature in the second connecting pipeline 41. When the detected temperature signal is higher than the set value, the temperature detection device 48 can control the first regulating valve 49 to open, thereby inputting nitrogen with a lower temperature into the second connecting pipeline 41 to reduce the temperature of the nitrogen in the second connecting pipeline 41, and the degree of opening of the first regulating valve 49 can be controlled according to the detected temperature. The higher the detected nitrogen temperature, the greater the opening degree of the first regulating valve 49.

[0044] In another preferred embodiment, a gas-liquid separation tank 50 is provided on the second connecting pipeline 41 between the low-temperature expansion end 45 and the heat exchanger 34. The bottom of the gas-liquid separation tank 50 is connected to the reflux port through the reflux pipeline 51. The second connecting pipeline 41 is respectively connected to the middle and top of the gas-liquid separation tank 50. After the nitrogen in the second connecting pipeline 41 is expanded through the low-temperature expansion end 45, part of the liquid nitrogen will be generated. By introducing the nitrogen and liquid nitrogen from the middle of the gas-liquid separation tank 50, the liquid nitrogen is stored at the bottom of the gas-liquid separation tank 50, and the nitrogen flows out through the top of the gas-liquid separation tank 50 to the second connecting pipeline 41 for continuous transportation. The liquid nitrogen stored at the bottom of the gas-liquid separation tank 50 can be transported to the top of the distillation tower 5 through the reflux port through the reflux pipe 51. Furthermore, a third liquid level detection device 52 can be provided in the gas-liquid separation tank 50, and a second regulating valve 53 connected to the third liquid level detection device 52 is provided on the reflux pipe 51. The third liquid level detection device 52 controls the opening and closing of the second regulating valve 53 through the detected liquid level signal. When the third liquid level detection device 52 detects that the liquid nitrogen in the gas-liquid separation tank 50 exceeds the set liquid level, the second regulating valve 53 can be controlled to open automatically, thereby transporting the liquid nitrogen to the top of the distillation tower 5.

[0045] In a more preferred embodiment, the top of the distillation tower 5 can be connected to the second cooling tower 19 through a nitrogen delivery pipeline 21, and part of the low-temperature nitrogen separated in the distillation tower 5 can be passed into the second cooling tower 19 through the nitrogen delivery pipeline 21, thereby cooling the cooling water in the second cooling tower 19 to prepare cooling water, thereby achieving full utilization of nitrogen and achieving the purpose of reducing production costs.

[0046] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Any modification or equivalent substitution that does not depart from the spirit and scope of the present invention shall be included in the scope of the technical solution of the present invention.

[0047] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Any modification or equivalent substitution that does not depart from the spirit and scope of the present invention shall be included in the scope of the technical solution of the present invention.

Claims

1. An air separation device, comprising an air filter (1), an air compressor unit (2), a precooling system (3), a purification system (4), a fractionation tower (5), a liquid oxygen storage system (6), a liquid nitrogen storage system (7) and a liquid argon storage system (8), characterized in that: The precooling system (3) comprises a first cooling tower (9), wherein the first cooling tower (9) is provided with an air inlet and an air outlet at the bottom and the top, respectively, the air inlet is connected to a first air pipeline (10), and the air outlet is connected to a second air pipeline (11), a spray chamber is provided in the first cooling tower (9), and a first spray assembly (12) and a second spray assembly (13) are provided in the spray chamber in order from bottom to top, and the first spray assembly (12) and the second spray assembly (13) are provided between the air inlet and the air outlet. The air inlet is arranged between the spray chamber to spray and cool the air introduced into the spray chamber, the first spray assembly (12) is connected to a first water supply pipeline (14), the second spray assembly (13) is connected to a second water supply pipeline (15), the bottom of the spray chamber is connected to a circulation pipeline (16), the circulation pipeline (16) is connected to a circulation pool (17), the first water supply pipeline (14) and the second water supply pipeline (15) are both connected to the circulation pool (17), wherein the second water supply pipeline (15) is provided with a A cooling mechanism (18) is provided for cooling cooling water inside the pipeline. A second cooling tower (19) is also provided on the second water supply pipeline (15) for preliminarily cooling the cooling water. A cooling chamber is provided inside the second cooling tower (19). A third spray assembly (20) is provided at the upper part of the cooling chamber. The third spray assembly (20) is connected to the circulating water pool (17) through a connecting pipe (24). The second water supply pipeline (15) is connected to the bottom of the cooling chamber. A nitrogen delivery pipeline (21) is also provided. The nitrogen delivery pipeline (21) is connected to the middle part of the cooling chamber so as to introduce nitrogen into the cooling chamber for cooling the cooling water. A gas outlet for discharging nitrogen is provided at the top of the second cooling tower (19). A second water storage cavity (26) is provided at the bottom of the spray chamber. The circulating pipeline (16) is connected to the second water storage cavity (26). A second drainage pipeline (27) is also provided at the bottom of the second water storage cavity (26).

2. An air separation device according to claim 1, characterized in that: A first water storage cavity (22) is provided at the bottom of the cooling chamber, a first liquid level detection device (23) is provided in the first water storage cavity (22), a first control valve (25) for controlling the on-off of the connecting pipe (24) is provided on the connecting pipe (24), the first liquid level detection device (23) is connected to the first control valve (25), and controls the opening and closing of the first control valve (25) according to a detected liquid level signal.

3. An air separation device according to claim 1, characterized in that: The second drainage pipeline (27) is provided with a second control valve (28), the first water supply pipeline (14) and the second water supply pipeline (15) are both provided with a first pump body (29), and the second gas transmission pipeline (11) is provided with a pressure detection device (30), the pressure detection device (30) is connected to a controller (31), and the controller (31) can control the operation of the second control valve (28) and the first pump body (29) respectively according to the pressure signal detected by the pressure detection device (30).

4. An air separation device according to claim 1, characterized in that: A second liquid level detection device (32) is installed in the second water storage cavity (26); a third control valve (33) for controlling the on-off of the circulation pipeline (16) is provided on the circulation pipeline (16); the second liquid level detection device (32) is connected to the third control valve (33), and the opening and closing of the third control valve (33) are controlled according to the detected liquid level signal.

5. An air separation device according to claim 1, characterized in that: The invention also comprises a nitrogen circulation system (54), wherein the nitrogen circulation system (54) comprises a heat exchanger (34), a circulating nitrogen compressor (35), a high-temperature expander (36), a low-temperature expander (37), a first booster compressor aftercooler (38), a second booster compressor aftercooler (39), a first connecting pipeline (40), a second connecting pipeline (41) and a third connecting pipeline (42); the bottom chamber of the fractionating tower (5) is provided with a gas outlet and a gas return port which are connected to each other; the top chamber of the fractionating tower (5) is provided with a reflux port; the high-temperature expander (36) has a high-temperature expansion end (43) and a high-temperature boosting end (44); and the low-temperature expander (37) has a low-temperature expansion end (45) and a low-temperature boosting end (46); One end of the first connecting pipeline (40) is connected to the air outlet, and the other end passes through the heat exchanger (34), the circulating nitrogen compressor (35), the high-temperature boost end (44), the first booster aftercooler (38), the low-temperature boost end (46), the second booster aftercooler (39), and then passes through the heat exchanger (34) to be connected to the air return port; One end of the second connecting pipeline (41) is connected to the first connecting pipeline (40) between the heat exchanger (34) and the gas return port, and the other end is connected to the first connecting pipeline (40) between the heat exchanger (34) and the circulating nitrogen compressor (35) after passing through the low-temperature expansion end (45); One end of the third connecting pipeline (42) is connected to the first connecting pipeline (40) between the circulating nitrogen compressor (35) and the high-temperature boosting end (44), and the other end passes through the heat exchanger (34) and the high-temperature expansion end (43) in sequence, and then passes through the heat exchanger (34) before being connected to the first connecting pipeline (40) between the heat exchanger (34) and the circulating nitrogen compressor (35).

6. An air separation device according to claim 5, characterized in that: The temperature control system further comprises a temperature control pipeline (47), one end of the temperature control pipeline (47) being connected to the first connecting pipeline (40) between the second connecting pipeline (41) and the air return port, and the other end of the temperature control pipeline (47) being connected to the second connecting pipeline (41), the second connecting pipeline (41) being provided with a temperature detection device (48), the temperature control pipeline (47) being provided with a first regulating valve (49) connected to the temperature detection device (48), and the temperature detection device (48) controlling the opening of the first regulating valve (49) by means of a detected temperature signal.

7. An air separation device according to claim 5, characterized in that: A gas-liquid separation tank (50) is arranged on the second connecting pipeline (41) between the low-temperature expansion end (45) and the heat exchanger (34); the bottom of the gas-liquid separation tank (50) is connected to the reflux port via the reflux pipeline (51); the second connecting pipeline (41) is respectively connected to the middle and top of the gas-liquid separation tank (50); a third liquid level detection device (52) is arranged in the gas-liquid separation tank (50); a second regulating valve (53) connected to the third liquid level detection device (52) is arranged on the reflux pipeline (51); the third liquid level detection device (52) controls the opening and closing of the second regulating valve (53) by detecting a liquid level signal.

8. An air separation device according to claim 5, characterized in that: The top of the fractionation tower (5) is connected to the second cooling tower (19) via a nitrogen delivery pipeline (21) so that nitrogen can be introduced into the second cooling tower (19).

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