VPSA oxygen production device and oxygen production method thereof

Abstract

The invention belongs to the technical field of oxygen production, and particularly relates to a VPSA oxygen production device and an oxygen production method.The VPSA oxygen production device comprises an air blower, a first adsorption tower, a second adsorption tower, a vacuum pump, a buffer tank, an oxygen compressor and an oxygen storage tank. After the process, the adsorption towers finish a complete'adsorption-regeneration 'cycle, preparation is made for next adsorption, the two adsorption towers alternately work according to a program, nitrogen and oxygen separation of raw material air can be realized through continuous air blowing and continuous vacuum pumping, oxygen production in the process is discontinuous, the purity of product oxygen is regularly changed, and the process is simple and convenient. During design, the oxygen buffer tank with reasonable volume is provided, so that the product oxygen can be uniformly mixed, the balanced product oxygen purity is realized, and meanwhile, the continuity of subsequent oxygen supply is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of oxygen production, in particular to a VPSA oxygen production device and an oxygen production method thereof. Background Art

[0002] VPSA oxygen production uses VPSA special molecular sieves to selectively adsorb impurities such as nitrogen, carbon dioxide and water in the air, and desorbs the molecular sieves under vacuum conditions to circulate and produce high-purity oxygen. Usually, air is extracted by a blower as raw material, and the air is adsorbed, filtered and separated to form the required gas.

[0003] Due to the different principles of oxygen production, it can be divided into molecular sieve principle, polymer oxygen-enriched membrane principle, water electrolysis principle and chemical reaction oxygen production principle. At present, in molecular sieve oxygen production devices, the raw air is pressurized by the compressor and enters the oxygen production device to achieve oxygen production. However, the air pressure in the current oxygen production device is relatively high, the air pressure is unstable, and it is difficult to produce stable and long-lasting oxygen. For this reason, we propose a VPSA oxygen production device and an oxygen production method thereof. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a VPSA oxygen production device and an oxygen production method thereof, which solve the background problem.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0006] A VPSA oxygen production device comprises a blower, a first adsorption tower, a second adsorption tower, a vacuum pump, a buffer tank, an oxygen compressor and an oxygen storage tank, wherein the blower is fixedly connected with the first adsorption tower and the second adsorption tower through pipelines, respectively; a first solenoid valve is installed on the pipeline connecting the blower and the first adsorption tower, a second solenoid valve is installed on the pipeline connecting the blower and the second adsorption tower, the vacuum pump is fixedly connected with the first adsorption tower and the second adsorption tower through pipelines, respectively; a third solenoid valve is installed on the pipeline connecting the vacuum pump and the first adsorption tower, a fourth solenoid valve is installed on the pipeline connecting the vacuum pump and the second adsorption tower, the first adsorption tower, the second adsorption tower and the buffer tank are fixedly connected through pipelines, the oxygen compressor is fixedly connected with the buffer tank through a pipeline, and the oxygen compressor is fixedly connected with the oxygen storage tank through a pipeline.

[0007] As a further feature of the present invention, a fifth solenoid valve is installed on the pipeline connecting the first adsorption tower and the second adsorption tower, and a sixth solenoid valve is installed on the pipeline connecting the second adsorption tower and the buffer tank.

[0008] As a further feature of the present invention, a gas flow valve is installed on the pipeline connecting the second adsorption tower and the buffer tank.

[0009] As a further feature of the present invention, the input end of the blower is fixedly connected to an inlet filter via a pipeline, and multiple groups of air filters are installed inside the inlet filter.

[0010] As a further feature of the present invention, a cooler is installed on the output end pipeline of the blower.

[0011] As a further feature of the present invention, a first connecting pipe is connected between the input end pipe of the blower and the output end pipe of the cooler, and a seventh solenoid valve is installed on the first connecting pipe.

[0012] As a further feature of the present invention, a fluid delivery pipe is fixedly connected between the input end pipe of the vacuum pump and the output end pipe of the vacuum pump, and an eighth solenoid valve is installed on the fluid delivery pipe.

[0013] As a further feature of the present invention, a nitrogen exhaust muffler is connected to the input end pipe of the vacuum pump, a pressure equalizing pipe is connected between the first adsorption tower and the second adsorption tower, a pressure equalizing valve is installed on the pressure equalizing pipe, and the first adsorption tower and the second adsorption tower are fixedly connected with a backwash pipe, and a flushing solenoid valve is installed on the backwash pipe.

[0014] A VPSA oxygen production method, the method comprising:

[0015] S1, turn on the vacuum pump and the fourth solenoid valve, the vacuum pump evacuates the inside of the second adsorption tower, and the vacuum pump and the fourth solenoid valve are turned off after the second adsorption tower reaches a certain pressure;

[0016] S2, adsorption process: open the first solenoid valve, the blower, the fifth solenoid valve and the oxygen compressor. Under the pressurized action of the blower, the air is filtered through the inlet filter 1 and enters the first adsorption tower. Then, it is sent to the subsequent oxygen compressor to be pressurized to the set pressure and then goes out of the boundary area to the user.

[0017] S3, pressure equalization and pressure reduction process: after the S2 adsorption process is completed, the pressure equalization valve installed between the first adsorption tower and the second adsorption tower is opened, and after the air pressure between the first adsorption tower and the second adsorption tower is balanced, the equalization valve is closed;

[0018] S4, vacuuming process: after the pressure equalization and pressure reduction process in S3 is completed, the fourth solenoid valve and the vacuum pump are opened;

[0019] S5, pressure equalization and pressure boosting process: after the vacuuming process in S4 is completed, the pressure equalization valve between the first adsorption tower and the second adsorption tower is opened;

[0020] S6, product gas backwashing process: at the end of the S5 pressure equalization and pressure boosting process, open the flushing solenoid valve on the backwashing pipe to perform gas backwashing;

[0021] Steps S1-S6 are executed cyclically to realize a continuous oxygen production process.

[0022] Beneficial Effects

[0023] The present invention provides a VPSA oxygen production device and an oxygen production method thereof. Compared with the prior art, it has the following beneficial effects:

[0024] 1. The VPSA oxygen production device and its oxygen production method. The oxygen production device undergoes an adsorption process, a pressure-equalizing and pressure-reducing process, a vacuuming process, a pressure-equalizing and pressure-increasing process, and a product gas backwashing process. After the above process, the adsorption tower completes a complete "adsorption-regeneration" cycle and is ready for the next adsorption. The two adsorption towers work alternately according to the program, and can realize continuous blowing and continuous vacuuming to separate nitrogen and oxygen from the raw air. The oxygen production in this process is intermittent, and the purity of the product oxygen changes regularly. During the design, we provide an oxygen buffer tank with a reasonable volume, which can meet the uniform mixing of the product oxygen to achieve a balanced product oxygen purity, while ensuring the continuity of the subsequent oxygen supply.

[0025] 2. The VPSA oxygen production device and oxygen production method thereof have multiple groups of air filters installed inside the inlet filter. The inlet filter can filter impurities in the incoming air to prevent impurities from affecting the preparation of oxygen. The cooler can cool the incoming air to prevent the high temperature of the incoming air from causing low efficiency in the subsequent adsorption tower. The nitrogen exhaust muffler can silence the air extracted by the vacuum pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of a VPSA oxygen production device of the present invention;

[0027] Figure 2 The figure is a schematic diagram of the flow structure of a VPSA oxygen production method of the present invention.

[0028] In the figure: 1. inlet filter; 2. blower; 3. cooler; 4. seventh solenoid valve; 5. first solenoid valve; 6. third solenoid valve; 7. second solenoid valve; 8. vacuum pump; 9. nitrogen exhaust muffler; 10. eighth solenoid valve; 11. fourth solenoid valve; 12. first adsorption tower; 13. fifth solenoid valve; 14. second adsorption tower; 15. sixth solenoid valve; 16. gas flow valve; 17. buffer tank; 18. oxygen compressor; 19. oxygen storage tank. DETAILED DESCRIPTION

[0029] 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.

[0030] See also Figure 1 The present invention provides a technical solution: a VPSA oxygen production device, comprising a blower 2, a first adsorption tower 12, a second adsorption tower 14, a vacuum pump 8, a buffer tank 17, an oxygen compressor 18 and an oxygen storage tank 19, the blower 2 is fixedly connected with the first adsorption tower 12 and the second adsorption tower 14 through pipelines, a first solenoid valve 5 is installed on the pipeline connecting the blower 2 and the first adsorption tower 12, a second solenoid valve 7 is installed on the pipeline connecting the blower 2 and the second adsorption tower 14, the vacuum pump 8 is fixedly connected with the first adsorption tower 12 and the second adsorption tower 14 through pipelines, a third solenoid valve 6 is installed on the pipeline connecting the vacuum pump 8 and the first adsorption tower 12, a fourth solenoid valve 11 is installed on the pipeline connecting the vacuum pump 8 and the second adsorption tower 14, the first adsorption tower 12, the second adsorption tower 14 and the buffer tank 17 are fixedly connected through pipelines, the oxygen compressor 18 is fixedly connected with the buffer tank 17 through pipelines, and the oxygen compressor 18 is fixedly connected with the oxygen storage tank 19 through pipelines.

[0031] A fifth solenoid valve 13 is installed on the pipeline connecting the first adsorption tower 12 and the second adsorption tower 14 , and a sixth solenoid valve 15 is installed on the pipeline connecting the second adsorption tower 15 and the buffer tank 17 .

[0032] A gas flow valve 16 is installed on the pipeline connecting the second adsorption tower 14 and the buffer tank 17 .

[0033] The input end of the blower 2 is fixedly connected to the inlet filter 1 through a pipeline, and multiple groups of air filters are installed inside the inlet filter 1.

[0034] The inlet filter 1 can filter impurities from the incoming air to prevent the impurities from affecting the preparation of oxygen.

[0035] A cooler 3 is installed on the output end pipeline of the blower 2 to cool the incoming air to avoid the high temperature of the incoming air resulting in low efficiency in the subsequent adsorption tower.

[0036] A first connecting pipe is connected between the input end pipe of the blower 2 and the output end pipe of the cooler 3 , and a seventh solenoid valve 4 is installed on the first connecting pipe.

[0037] A fluid delivery pipe is fixedly connected between the input end pipe of the vacuum pump 8 and the output end pipe of the vacuum pump 8 , and an eighth solenoid valve 10 is installed on the fluid delivery pipe.

[0038] A nitrogen exhaust muffler 9 is connected to the input end pipeline of the vacuum pump 8, a pressure equalizing pipe is connected between the first adsorption tower 12 and the second adsorption tower 14, a pressure equalizing valve is installed on the pressure equalizing pipe, the first adsorption tower 12 and the second adsorption tower 14 are fixedly connected with a backwash pipe, and a flushing solenoid valve is installed on the backwash pipe.

[0039] The nitrogen exhaust muffler 9 can silence the air extracted by the vacuum pump 8.

[0040] A VPSA oxygen production method, the method comprising:

[0041] S1, open the vacuum pump 8 and the fourth solenoid valve 11, the vacuum pump 8 evacuates the inside of the second adsorption tower 14, and the vacuum pump 8 and the fourth solenoid valve 11 are closed after the second adsorption tower 14 reaches a certain pressure;

[0042] S2, adsorption process: open the first solenoid valve 5, the blower 2, the fifth solenoid valve 13 and the oxygen compressor 18. Under the pressurized action of the blower 2, the air is filtered through the inlet filter 1 and enters the first adsorption tower 12. The H2O, N2 and other components of the air entering the first adsorption tower 12 are successively adsorbed by various adsorbents in the adsorption tower. This process of adsorbing impurity components in the raw air by the adsorbent as the pressure increases is called the adsorption process. During the adsorption process, product oxygen with a purity ranging from 95.5% to about 85% is obtained from the top of the adsorption tower. After the product oxygen of different purities in the process is mixed in the oxygen buffer tank 17, the product oxygen purity from the output port of the buffer tank 17 is one-step realized to achieve a stable purity product gas of ≥80% O2 (purity fluctuation is less than 0.5%), and then sent to the subsequent oxygen compressor 18 for pressurization to the set pressure and then out of the boundary area to the user;

[0043] S3, equalizing and reducing pressure process: after the S2 adsorption process is completed, the equalizing valve installed between the first adsorption tower 12 and the second adsorption tower 14 is opened. In order to ensure that the oxygen in the adsorption tower is fully recovered and the oxygen yield is increased, the high oxygen-rich gas (gas of <85% O2-20% O2) that does not meet the product gas purity requirement in the adsorption tower is recovered and adsorbed again. That is, the equalizing valve between the two adsorption towers is opened at this time, and the gases inside the first adsorption tower 12 and the second adsorption tower 14 are put into the second adsorption tower 14 which has been regenerated and is under vacuum pressure. In this process, the adsorption tower is in the process of venting from the top of the tower and accompanied by pressure reduction until the pressures of the two towers are basically close. After the air pressure between the first adsorption tower 12 and the second adsorption tower 14 is balanced, the equalizing valve is closed. This process is called the equalizing and reducing pressure process. The pressure change range of the adsorption tower is: +49KPa→-10KPa;

[0044] The equalizing and reducing pressure process not only reduces the gas partial pressure in the adsorption tower, gradually reduces the adsorption capacity of the adsorbent for the nitrogen component, but also recovers part of the oxygen-rich gas in the bed with a higher oxygen content than the raw air and enters another adsorption tower for re-adsorption, which not only ensures the full recovery of oxygen, but also improves the yield of the oxygen component;

[0045] S4, vacuuming process: After the pressure equalization and pressure reduction process in S3 is completed, the fourth solenoid valve 11 and the vacuum pump 8 are opened. In order to completely regenerate the adsorbent, the adsorption bed layer of the second adsorption tower 14 is vacuumed by the vacuum pump 8 in the opposite direction of the adsorption direction, and the partial pressure of the impurity components is further reduced, so that the impurity components adsorbed by the adsorbent are fully and completely desorbed, and the impurity components are extracted from the adsorption tower by the strong external action of the vacuum pump 8. The process in which the adsorbent in the adsorption tower is completely regenerated is called the vacuuming process. The pressure change range of the adsorption tower during the vacuuming process: -10KPa→ -50KPa;

[0046] The main purpose of the vacuuming process is to achieve a better desorption and regeneration process for the various adsorbents in the adsorption tower;

[0047] S5, equalizing and boosting process: After the vacuuming process in S4 is completed, the equalizing valve between the first adsorption tower 12 and the second adsorption tower 14 is opened. At this time, the adsorption tower is in a negative pressure vacuum state (~-50KPa). The equalizing valve between the two adsorption towers is opened. Due to the pressure difference between the two towers, the oxygen-rich gas in one of the adsorption towers in a positive pressure state (~+49KPa) is used to inflate and boost the pressure of the adsorption tower. This process corresponds to the equalizing and depressurizing process of the other adsorption tower. We call this process the uniform boosting process. The pressure change range of the adsorption tower is: -50KPa→-10KPa;

[0048] The uniform pressure-raising process is not only a process of pressure recovery and pressure-raising in the adsorption tower, but also a process for better recovery of oxygen-enriched air (gas with less than 93% O2 ​​to 20% O2) from other towers.

[0049] S6, product gas backwashing process: At the end of the S5 equalization and pressure boosting process, open the flushing solenoid valve on the backwashing pipe. Because the pressure in the adsorption tower cannot reach the oxygen adsorption pressure, and there is still some residual low-oxygen gas in the top of the adsorption tower and the top pipeline during the equalization process that has not come into contact with the molecular sieve, in order to ensure the purity quality when the adsorption tower starts to produce oxygen, we use product oxygen to reversely blow oxygen to the top of the adsorption tower at this time. This process is called the product gas backwashing process. The pressure change range of the adsorption tower is: -10KPa→+15KPa;

[0050] The product gas backwashing process is mainly to ensure that the low oxygen-rich gas in the dead space at the top of the adsorption tower can fully contact the adsorbent for secondary adsorption, to ensure that the product oxygen purity is high in the initial stage of oxygen production, and to ensure that the pressure in the adsorption tower reaches the initial pressure required by the adsorption process;

[0051] Steps S1-S6 are executed cyclically to realize a continuous oxygen production process.

[0052] The working principle of the present invention is as follows: when in use, firstly, the vacuum pump 8 and the fourth solenoid valve 11 are turned on, and the vacuum pump 8 evacuates the inside of the second adsorption tower 14. When the second adsorption tower 14 reaches a certain pressure, the vacuum pump 8 and the fourth solenoid valve 11 are turned off, and then the first solenoid valve 5, the blower 2, the fifth solenoid valve 13 and the oxygen compressor 18 are turned on. Under the pressurized action of the blower 2, the air is filtered through the inlet filter 1 and enters the first adsorption tower 12. The H2O, N2 and other components of the air entering the first adsorption tower 12 are sequentially adsorbed by a variety of adsorbents in the adsorption tower. The product oxygen of different purities in the process is mixed in the oxygen buffer tank 17 and then goes out of the boundary area to the user.

[0053] Then, the pressure equalizing valve installed between the first adsorption tower 12 and the second adsorption tower 14 is opened. At this time, the pressure equalizing valve between the two adsorption towers is opened, and the gases inside the first adsorption tower 12 and the second adsorption tower 14 are transferred along the adsorption mass transfer direction to transfer the oxygen-rich gas with a higher positive pressure in the tower into the second adsorption tower 14 which has been regenerated and is in a vacuum pressure state. In this process, the adsorption tower is in the process of venting gas from the top of the tower and the pressure is reduced until the pressures of the two towers are basically close. After the air pressure between the first adsorption tower 12 and the second adsorption tower 14 is balanced, the equalizing valve is closed;

[0054] After the pressure equalization and pressure reduction process is completed, the fourth solenoid valve 11 and the vacuum pump 8 are opened. In order to completely regenerate the adsorbent, the adsorption bed of the second adsorption tower 14 is evacuated by the vacuum pump 8 in the opposite direction of the adsorption direction to further reduce the partial pressure of the impurity components, so that the impurity components adsorbed by the adsorbent are fully and completely desorbed, and the adsorbent is extracted from the adsorption tower by the strong external action of the vacuum pump 8. The process in which the adsorbent in the adsorption tower is completely regenerated is called the vacuuming process. The main purpose of the vacuuming process is to achieve a better desorption and regeneration process for the various adsorbents in the adsorption tower;

[0055] After the vacuuming process is completed, the pressure equalizing valve between the first adsorption tower 12 and the second adsorption tower 14 is opened. At this time, the adsorption tower is in a negative pressure vacuum state. The pressure equalizing valve between the two adsorption towers is opened. Due to the pressure difference between the two towers, the oxygen-rich gas in one of the adsorption towers in a positive pressure state is used to inflate and pressurize the adsorption tower. This process corresponds to the pressure equalizing and depressurizing process of the other adsorption tower. We call this process a uniform pressure increasing process. The uniform pressure increasing process is not only a pressure recovery and pressurization process of the adsorption tower, but also a process for better recovery of oxygen-rich air from other towers.

[0056] Finally, at the end of the equalizing and boosting process, open the flushing solenoid valve on the backwashing pipe. Because the pressure in the adsorption tower cannot reach the oxygen adsorption pressure, and there is still some residual low-oxygen gas in the top of the adsorption tower and the top pipeline during the equalizing process that fails to contact the molecular sieve, in order to ensure the purity quality when the adsorption tower starts to produce oxygen, we use product oxygen to blow oxygen back to the top of the adsorption tower at this time. This process is called the product gas backwashing process;

[0057] This oxygen production device goes through the adsorption process, pressure equalization and reduction process, vacuum process, pressure equalization and boosting process and product gas backwashing process. After the above process, the adsorption tower completes a complete "adsorption-regeneration" cycle and is ready for the next adsorption. The two adsorption towers work alternately according to the program, which can realize continuous blowing and continuous vacuuming to separate nitrogen and oxygen from the raw air. The oxygen production in this process is intermittent, and the purity of the product oxygen changes regularly. During the design, we provide an oxygen buffer tank with a reasonable volume to meet the uniform mixing of the product oxygen and achieve a balanced product oxygen purity, while ensuring the continuity of the subsequent oxygen supply.

[0058] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A VPSA oxygen production device, comprising a blower (2), a first adsorption tower (12), a second adsorption tower (14), a vacuum pump (8), a buffer tank (17), an oxygen compressor (18) and an oxygen storage tank (19), characterized in that: The blower (2) is fixedly connected to the first adsorption tower (12) and the second adsorption tower (14) through pipelines, respectively; a first solenoid valve (5) is installed on the pipeline connecting the blower (2) and the first adsorption tower (12); a second solenoid valve (7) is installed on the pipeline connecting the blower (2) and the second adsorption tower (14); the vacuum pump (8) is fixedly connected to the first adsorption tower (12) and the second adsorption tower (14) through pipelines, respectively; a third solenoid valve (6) is installed on the pipeline connecting the vacuum pump (8) and the first adsorption tower (12); a fourth solenoid valve (11) is installed on the pipeline connecting the vacuum pump (8) and the second adsorption tower (14); the first adsorption tower (12), the second adsorption tower (14) and the buffer tank (17) are fixedly connected through pipelines; the oxygen compressor (18) is fixedly connected to the buffer tank (17) through a pipeline; and the oxygen compressor (18) is fixedly connected to the oxygen storage tank (19) through a pipeline.

2. A VPSA oxygen generator according to claim 1, characterized in that: A fifth solenoid valve (13) is installed on the pipeline connecting the first adsorption tower (12) and the second adsorption tower (14), and a sixth solenoid valve (15) is installed on the pipeline connecting the second adsorption tower (15) and the buffer tank (17).

3. A VPSA oxygen generator according to claim 2, characterized in that: A gas flow valve (16) is installed on the pipeline connecting the second adsorption tower (14) and the buffer tank (17).

4. A VPSA oxygen generator according to claim 3, characterized in that: The input end of the blower (2) is fixedly connected to an inlet filter (1) via a pipeline, and a plurality of groups of air filter screens are installed inside the inlet filter (1).

5. A VPSA oxygen generator according to claim 4, characterized in that: A cooler (3) is installed on the output end pipeline of the blower (2).

6. A VPSA oxygen generator according to claim 5, characterized in that: A first connecting pipe is connected between the input end pipe of the blower (2) and the output end pipe of the cooler (3), and a seventh solenoid valve (4) is installed on the first connecting pipe.

7. A VPSA oxygen generator according to claim 6, characterized in that: A fluid delivery pipe is fixedly connected between the input end pipe of the vacuum pump (8) and the output end pipe of the vacuum pump (8), and an eighth solenoid valve (10) is installed on the fluid delivery pipe.

8. A VPSA oxygen generator according to claim 7, characterized in that: The input end pipeline of the vacuum pump (8) is connected to a nitrogen exhaust muffler (9); a pressure equalizing pipe is connected between the first adsorption tower (12) and the second adsorption tower (14); a pressure equalizing valve is installed on the pressure equalizing pipe; the first adsorption tower (12) and the second adsorption tower (14) are both fixedly connected to a backwashing pipe, and a flushing solenoid valve is installed on the backwashing pipe.

9. A VPSA oxygen production method, based on a VPSA oxygen production device according to any one of claims 1 to 8, characterized in that: The method comprises: S1, open the vacuum pump 8 and the fourth solenoid valve 11, the vacuum pump 8 evacuates the inside of the second adsorption tower 14, and the vacuum pump 8 and the fourth solenoid valve 11 are closed after the second adsorption tower 14 reaches a certain pressure; S2, adsorption process: open the first solenoid valve 5, the blower 2, the fifth solenoid valve 13 and the oxygen compressor 18, under the pressurized action of the blower 2, the air is filtered through the inlet filter 1 and enters the first adsorption tower 12, and then sent to the subsequent oxygen compressor 18 to be pressurized to the set pressure and then go out of the boundary area to the user; S3, pressure equalization and pressure reduction process: after the S2 adsorption process is completed, the pressure equalization valve installed between the first adsorption tower 12 and the second adsorption tower 14 is opened, and after the air pressure between the first adsorption tower 12 and the second adsorption tower 14 is balanced, the equalization valve is closed; S4, vacuuming process: after the pressure equalization and pressure reduction process in S3 is completed, the fourth solenoid valve 11 and the vacuum pump 8 are opened; S5, pressure equalization and pressure boosting process: after the vacuuming process in S4 is completed, the pressure equalization valve between the first adsorption tower 12 and the second adsorption tower 14 is opened; S6, product gas backwashing process: at the end of the S5 pressure equalization and pressure boosting process, open the flushing solenoid valve on the backwashing pipe to perform gas backwashing; Steps S1-S6 are executed cyclically to realize a continuous oxygen production process.

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