Single-tower nitrogen making device

Abstract

The utility model discloses a single-tower nitrogen-making device, which comprises an air compressor; a filter assembly; the adsorption tower is provided with a nitrogen-making inlet and a nitrogen-making outlet, a nitrogen-making molecular sieve is arranged in the adsorption tower, and the nitrogen-making inlet is communicated with the filtering assembly; the buffer tank is provided with a buffer inlet and a buffer outlet, and the buffer inlet is communicated with the nitrogen generation outlet; the return pipe is arranged between the adsorption tower and the buffer tank, and a return valve is arranged on the return pipe; the nitrogen storage tank is provided with a nitrogen storage inlet and a nitrogen storage outlet, and the nitrogen storage inlet is communicated with the buffer outlet. According to the single-tower nitrogen-making device, the single adsorption tower is used for adsorbing oxygen to prepare nitrogen, when a single molecular sieve needs to be regenerated, the nitrogen in the buffer tank flows back into the adsorption tower through the return pipe to promote regeneration of the single molecular sieve, meanwhile, the gas use continuity of the rear end is guaranteed, and due to the fact that only the single adsorption tower is arranged, the structure is simplified, and the cost is reduced. And the required number of valves and pipelines is reduced, so that the system cost and the failure rate are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of nitrogen production, in particular to a single-tower nitrogen production device. Background Art

[0002] Nitrogen production equipment uses air as raw material and molecular sieve as adsorbent. It uses the principle of pressure swing adsorption and utilizes molecular sieve to selectively adsorb oxygen and nitrogen to separate nitrogen and oxygen. As a new gas separation technology, it has the characteristics of environmental friendliness, low cost and high efficiency. It separates gas mixtures through the difference in adsorption properties of molecular sieves for different gas molecules, thereby obtaining high-concentration nitrogen.

[0003] In the prior art, Chinese utility model patents such as CN108298509A, CN201500505U, CN212246223U, CN216377489U, and CN220537498U all disclose the technology of using molecular sieves to produce nitrogen. At the same time, a double-tower process is used to produce nitrogen. Since the molecular sieve in the adsorption tower reaches saturation after a period of adsorption, it loses its separation effect and needs to be regenerated. During the regeneration, it switches to another adsorption tower. However, the equipment for producing nitrogen using the double-tower process has a complex structure and program control, and multiple valves need to be set to control the flow direction of the gas, which is costly and increases the failure rate.

[0004] Therefore, it is necessary to improve the nitrogen production equipment in the prior art. Utility Model Content

[0005] The utility model aims to overcome the defects in the prior art and provide a single-tower nitrogen production device with a simplified structure, reduced cost and reduced failure rate.

[0006] In order to achieve the above technical effects, the technical solution of the utility model is: a single-tower nitrogen production device, comprising:

[0007] An air compressor, wherein the input end of the air compressor is connected to the outside world;

[0008] A filter assembly, the filter assembly is connected to the output end of the air compressor to filter out impurities in the air output by the air compressor;

[0009] An adsorption tower, wherein the number of the adsorption tower is one, the adsorption tower is provided with a nitrogen production inlet and a nitrogen production outlet, a nitrogen production molecular sieve is provided in the adsorption tower and is located between the nitrogen production inlet and the nitrogen production outlet, the nitrogen production inlet is connected to the output end of the filter component and is connected to the outside through a first valve;

[0010] A buffer tank, wherein the buffer tank is provided with a buffer inlet and a buffer outlet, and the buffer inlet is connected to the nitrogen production outlet;

[0011] A reflux pipe, the reflux pipe is arranged between the adsorption tower and the buffer tank, and a reflux valve is arranged on the reflux pipe;

[0012] A nitrogen storage tank is provided with a nitrogen storage inlet and a nitrogen storage outlet, and the nitrogen storage inlet is connected to the buffer outlet.

[0013] Preferably, in order to facilitate operation, ensure sealing performance, reduce fluid resistance, and extend the service life of the device, the reflux valve is a ball valve.

[0014] Preferably, in order to simplify the structure and reduce the cost, both ends of the reflux pipe are respectively connected to the nitrogen production outlet and the buffer inlet.

[0015] Preferably, in order to facilitate the detection of nitrogen purity to determine whether the produced nitrogen is qualified, the buffer outlet is connected to a gas purity analyzer, a second valve is provided between the buffer outlet and the nitrogen storage inlet, the buffer outlet is connected to the outside through a third valve, or the buffer outlet is connected to the input end of the air compressor through the third valve.

[0016] Preferably, in order to reduce the load of the nitrogen-producing molecular sieve in the adsorption tower, the buffer outlet is connected to the input end of the air compressor through a third valve.

[0017] Preferably, in order to facilitate the adjustment of the ratio of unqualified nitrogen to air at the air compressor input end, the third valve is a proportional valve.

[0018] Preferably, in order to ensure the stability of system operation and reduce noise, a muffler is connected to one end of the first valve away from the adsorption tower.

[0019] Preferably, in order to ensure the filtering effect and facilitate the discharge of impurities and wastes generated during the filtering, the filtering assembly includes at least two filters connected in sequence, and the filters are connected to a first drain valve.

[0020] Preferably, in order to filter out moisture in the air, the filter assembly further includes a cold dryer, and the cold dryer is connected between two of the filters.

[0021] Preferably, in order to buffer and stabilize the compressed air and reduce the air temperature to reduce the air humidity, an air storage tank is also provided between the output end of the air compressor and the filter assembly.

[0022] In summary, compared with the prior art, the single-tower nitrogen making device of the utility model utilizes a single adsorption tower to adsorb oxygen to prepare nitrogen. When the single molecular sieve needs to be regenerated, the nitrogen in the buffer tank flows back to the adsorption tower through the reflux pipe to promote the regeneration of the single molecular sieve, while ensuring the continuity of gas use at the rear end. Since only a single adsorption tower is provided, the structure is simplified, the number of valves and pipelines required is reduced, thereby reducing system cost and failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of the first embodiment;

[0024] Figure 2 is a schematic structural diagram of a second embodiment;

[0025] Figure 3 is a schematic structural diagram of a fourth embodiment;

[0026] In the figure: 1. air compressor; 101. air compressor valve; 2. filter assembly; 201. filter; 202. first drain valve; 203. cold dryer; 204. filter valve; 3. adsorption tower; 301. first valve; 302. muffler; 4. buffer tank; 5. reflux pipe; 501. reflux valve; 6. nitrogen storage tank; 7. gas purity analyzer; 8. second valve; 9. third valve; 10. dust removal and filtering device; 11. air storage tank; 12. flow meter; 13. second drain valve; 14. collection tank. DETAILED DESCRIPTION

[0027] The following is a further description of the specific implementation of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0028] First embodiment

[0029] like Figure 1 As shown, the single-tower nitrogen production device of the first embodiment of the utility model comprises:

[0030] Air compressor 1, the input end of the air compressor 1 is connected to the outside world;

[0031] The filter assembly 2 is connected to the output end of the air compressor 1 to filter out impurities in the air output by the air compressor 1;

[0032] Adsorption tower 3, the number of adsorption tower 3 is one, the adsorption tower 3 is provided with a nitrogen production inlet and a nitrogen production outlet, the adsorption tower 3 is provided with a nitrogen production molecular sieve located between the nitrogen production inlet and the nitrogen production outlet, the nitrogen production inlet is connected to the output end of the filter component 2 and is connected to the outside through the first valve 301;

[0033] A buffer tank 4 is provided with a buffer inlet and a buffer outlet, and the buffer inlet is connected to the nitrogen production outlet;

[0034] A reflux pipe 5, which is disposed between the adsorption tower 3 and the buffer tank 4, and a reflux valve 501 is disposed on the reflux pipe 5;

[0035] The nitrogen storage tank 6 is provided with a nitrogen storage inlet and a nitrogen storage outlet, and the nitrogen storage inlet is communicated with the buffer outlet.

[0036] In the single-tower nitrogen making device of the present embodiment, only one adsorption tower 3 is provided, and a nitrogen-making molecular sieve (not shown in the figure) is built in the adsorption tower 3. When the nitrogen-making molecular sieve is not saturated with adsorption, the air is transported by the air compressor 1, and the air is filtered out by the filter assembly 2 to remove impurities such as particulate matter and moisture in the air, and then the air is passed into the adsorption tower 3. The nitrogen-making molecular sieve adsorbs oxygen, and after the nitrogen passes through the nitrogen-making molecular sieve, it passes through the buffer tank 4 to adjust the nitrogen flow rate and pressure, and then the nitrogen enters the nitrogen storage tank 6. When the nitrogen is needed, the nitrogen produced is output through the nitrogen storage tank 6.

[0037] When the nitrogen-generating molecular sieve reaches a saturated state, the nitrogen-generating molecular sieve needs to be regenerated, and the reflux valve 501 is opened to allow part of the nitrogen pre-stored in the buffer tank 4 to pass into the adsorption tower 3. During the regeneration process of the nitrogen-generating molecular sieve, the regeneration speed can be accelerated by passing nitrogen, because the regeneration process usually includes steps such as pressure reduction, heating and purging to remove impurities adsorbed on the molecular sieve, and in this process, passing nitrogen can help remove the residual gas on the nitrogen-generating molecular sieve, thereby accelerating the regeneration process.

[0038] Therefore, compared with other double-tower structures, the above-mentioned single-tower nitrogen production device only adopts one adsorption tower 3, and the buffer tank 4 is used to ensure the regeneration of the nitrogen-making molecular sieve in the adsorption tower 3 and the continuity of gas use at the rear end, thereby reducing the number of adsorption towers 3 and related valves, simplifying the structure, and reducing costs and failure rates.

[0039] In the single-tower nitrogen production device of this embodiment, the external air first passes through the air compressor 1. The air compressor 1 can provide stable and continuous compressed air, which is the cornerstone for ensuring efficient and stable operation of the nitrogen production process. The role of the air compressor 1 is manifested in: first, the air compressor 1 ensures the efficiency and continuity of the nitrogen production process. The compressed air it provides is an indispensable step in nitrogen production and is directly related to the optimization of nitrogen production and purity; second, the performance of the air compressor 1 has a direct impact on the overall efficiency, stability and nitrogen purity of the nitrogen production system.

[0040] In order to ensure the continuous output of stable compressed air to the adsorption tower 3, an air storage tank 11 is also provided between the output end of the air compressor 1 and the filter assembly 2, and the output end of the air compressor 1 is connected to the air storage tank 11 through the air pressure valve 101. The compressed air output by the air compressor 1 often has pulsation of air flow pressure, and the air storage tank 11 can eliminate or reduce such pulsation, making the air flow more stable, extending the cycle of "start-stop" or "load-unload" of the air compressor 1, reducing the switching speed of the electrical valve, and preventing the compressed air pipeline from returning gas due to some reasons during the shutdown of the air compressor 1, and backflowing into the air compressor 1 to cause malfunction and damage; in addition, the air storage tank 11 is a cylindrical heat sink with a large area, and the incoming gas swirls and attaches to the wall in the tank, which can not only cool the compressed air, but also help to precipitate the moisture and dust impurities therein, which will fall to the bottom of the air storage tank 11 and precipitate, thereby further achieving the effect of water removal and sewage discharge. Therefore, the air storage tank 11 is arranged at the output end of the air compressor 1, which can play multiple functions such as buffering, cooling, dehumidification, and impurity removal, ensuring the efficient and stable operation of the nitrogen production system.

[0041] After passing through the air storage tank 11, the compressed air is transported to the filter assembly 2, and impurities such as moisture, oil droplets, and particles in the compressed air are filtered out by the filter assembly 2. A further improvement is that the filter assembly 2 includes at least two filters 201 connected in sequence, and the filter 201 is connected to a first drain valve 202. The filter assembly 2 also includes a cold dryer 203, and the cold dryer 203 is connected between two of the filters 201.

[0042] Specifically, in the nitrogen generating device of this embodiment, the filter assembly 2 includes four filters 201, namely a primary filter 201, a secondary filter 201, a tertiary filter 201 and a quaternary filter 201. In addition, the input end and the output end of the cold dryer 203 are respectively connected to the primary filter 201 and the secondary filter 201.

[0043] Among them, the function of the cold dryer 203 is mainly to remove moisture from the compressed air and ensure that the compressed air entering the adsorption tower 3 is dry, which helps the adsorption tower 3 to work better and prolongs the service life of the nitrogen-making molecular sieve; specifically, the cold dryer 203 is a device for treating moisture in the air. By removing moisture from the air, it can prevent moisture from damaging machinery, electronic equipment and other equipment. Since in the single-tower nitrogen making system, keeping the air dry is crucial to the efficiency of the nitrogen making process and the purity of the nitrogen, the cold dryer 203 plays a key role in the single-tower nitrogen making device of this embodiment.

[0044] The four filters 201 are provided to ensure the quality and purity of the compressed air entering the adsorption tower 3; specifically, the first-stage filter 201 is a pre-filter 201, which is mainly used to remove large particles of impurities in the air, such as dust, sand, etc., which helps the normal operation of the subsequent filtering device, prolongs its service life, and reduces the potential damage of impurities to subsequent equipment; the second-stage filter 201 further refines the filtering process, can remove smaller particles and certain specific pollutants, and through the second-stage filtration, can further reduce the impurity content in the air, and provide purer compressed air for the subsequent nitrogen production process; the third-stage filter 201 is usually used to remove oil mist and other organic pollutants to ensure that the air entering the adsorption tower 3 is clean; the fourth-stage filter 201 is used as the final filter 201 to remove any residual impurities and tiny particles to ensure that the compressed air entering the adsorption tower 3 has high purity and quality. The compressed air after the four-stage filtration can meet the high quality requirements of the adsorption tower 3 for the raw gas, thereby improving the nitrogen production efficiency and nitrogen purity.

[0045] A filter valve 204 is provided between the fourth-stage filter 201 and the adsorption tower 3 to control the on-off of the pipeline between the filter assembly 2 and the adsorption tower 3 , that is, after the filter valve 204 is opened, the filtered clean compressed gas can enter the adsorption tower 3 .

[0046] The cold dryer 203 and the four filters 201 are all connected to a first drain valve 202 . The first drain valve 202 is an automatic drain valve, which is convenient for discharging impurities trapped by the filter assembly 2 during the filtering process to ensure the continuous operation of the filter assembly 2 .

[0047] After the clean compressed air enters the adsorption tower 3, the oxygen in the air is adsorbed by the nitrogen-making molecular sieve, and the nitrogen passes through the nitrogen-making molecular sieve, is discharged through the nitrogen-making outlet, and then is transported to the buffer tank 4 through the buffer inlet. The main function of the buffer tank 4 is to stabilize the airflow, reduce the pressure fluctuation of the system, ensure that the gas passes through each component smoothly, and is used to cache part of the nitrogen, which is used to be transported to the adsorption tower 3 through the reflux pipe 5 when the nitrogen-making molecular sieve is regenerated, so as to accelerate the regeneration of the nitrogen-making molecular sieve.

[0048] The buffer outlet is connected to the nitrogen gas storage inlet through the dust removal filter device 10 and the flow meter 12 in turn, so that the nitrogen after passing through the buffer tank 4 is filtered out of impurities in the nitrogen through the dust removal filter device 10, ensuring that the clean nitrogen enters the nitrogen storage tank 6, and the flow meter 12 is used to conveniently detect the nitrogen flow entering the nitrogen storage tank 6. The nitrogen storage tank 6 is connected to an exhaust valve. When nitrogen is needed, the exhaust valve is opened to discharge the clean nitrogen.

[0049] The air storage tank 11, the buffer tank 4, the dust removal and filtering device 10 and the nitrogen storage tank 6 are all connected to a second drain valve 13. The second drain valve 13 is used to conveniently discharge impurities accumulated inside the air storage tank 11, the buffer tank 4, the dust removal and filtering device 10 and the nitrogen storage tank 6 after long-term operation, so as to ensure the long-term and stable operation of the above-mentioned devices.

[0050] A further improvement is that the reflux valve 501 is a ball valve.

[0051] Compared with other valves, the ball valve opens and closes quickly and is easy to operate. Since the opening and closing part of the ball valve is a sphere, it generally only needs to be rotated 90° to quickly open or close. Compared with the stop valve that requires multiple turns of rotation, the operation is faster; and since the sealing surface of the ball valve is a spherical surface, it fits tightly with the valve seat, so its sealing performance is excellent; not only that, the channel design of the ball valve makes the resistance of nitrogen smaller when passing through, which is more conducive to reducing energy consumption and ensuring fluid stability, so that nitrogen can enter the adsorption tower 3; in addition, the ball valve has a simple structure, and the friction between the valve core and the valve seat during the opening and closing process is small, so the service life of the reflux valve 501 can be guaranteed.

[0052] A further improvement is that both ends of the reflux pipe 5 are connected to the nitrogen outlet and the buffer inlet, respectively. With the above structure, it is not necessary to open other pipeline structures on the adsorption tower 3 and the buffer tank 4, which is conducive to simplifying the structure and ensuring the structural strength of the adsorption tower 3 and the buffer tank 4.

[0053] A further improvement is that the buffer outlet is connected to a gas purity analyzer 7 , a second valve 8 is provided between the buffer outlet and the nitrogen gas storage inlet, and the buffer outlet is connected to the outside through a third valve 9 .

[0054] By setting up a gas purity analyzer 7, it is convenient to detect the purity of nitrogen passing through the buffer tank 4, so that nitrogen gas with unqualified purity is discharged to the outside through the third valve 9, while nitrogen with qualified purity is collected in the nitrogen storage tank 6 through the second valve 8.

[0055] A further improvement is that a muffler 302 is connected to one end of the first valve 301 away from the adsorption tower 3 .

[0056] The muffler 302 is arranged at the bottom of the adsorption tower 3, and is mainly used to reduce the noise level. In the nitrogen production process, especially when the nitrogen production molecular sieve in the adsorption tower 3 is regenerated, due to factors such as gas flow and pressure change, a large noise may be generated. By arranging the muffler 302 at the bottom of the adsorption tower 3, the propagation of these noises can be effectively reduced, thereby protecting the hearing of the operator and reducing the noise pollution to the surrounding environment; in addition, reducing the noise can also help improve the operational safety and stability of the nitrogen production system. Excessive noise may interfere with the judgment and operation of the operator and increase the risk of misoperation. The use of the muffler 302 can reduce such interference and improve the work efficiency and safety of the operator.

[0057] Second embodiment

[0058] like Figure 2 As shown, the single-tower nitrogen production device of the second embodiment of the utility model is based on the first embodiment, and the difference is that the buffer outlet is connected to the input end of the air compressor 1 through the third valve 9.

[0059] The nitrogen content in the gas discharged through the third valve 9 is much higher than the nitrogen content in the original air. Therefore, the nitrogen with unqualified purity is introduced into the output end of the air compressor 1, and the nitrogen with unqualified purity is introduced into the adsorption tower 3 for nitrogen production after filtering operation again. Compared with introducing pure air into the adsorption tower 3 for nitrogen production through filtering operation, the nitrogen production efficiency and the purity of the final nitrogen can be significantly improved, and the utilization of raw materials can be reduced.

[0060] Third embodiment

[0061] Although not shown in the figure, the single-tower nitrogen production device of the third embodiment of the present invention is based on the second embodiment, except that the third valve 9 is a proportional valve.

[0062] After adopting the above design, the gas collected at the input end of the air compressor 1 is a mixed gas formed by mixing the outside air and the nitrogen gas with substandard purity, that is, the air compressor 1 compresses the nitrogen gas with substandard purity and the outside air and then delivers them to the air storage tank 11. The third valve 9 adopts a proportional valve, which can adjust the ratio between the outside air and the nitrogen gas with substandard purity. According to the amount of nitrogen gas with substandard purity generated, the amount of gas delivered to the air compressor 1 is adjusted to ensure that the air compressor 1 can continuously collect the above mixed gas, which is conducive to the continuous and stable operation of the nitrogen production system and improves the nitrogen production efficiency.

[0063] Fourth embodiment

[0064] like Figure 3 As shown, the single-tower nitrogen production device of the fourth embodiment of the utility model is based on the third embodiment, but differs in that it further includes a collecting tank 14 , which is connected to the output end of each first sewage valve 202 and the output end of each second sewage valve 13 .

[0065] After adopting the above structure, it is convenient to centrally collect impurities such as oil mist, moisture, and particles filtered out and generated by the nitrogen making device during the nitrogen making process, reduce the cleaning workload of workers, and avoid differences in the discharge positions of the first sewage valve 202 and the second sewage valve 13, which may cause the discharged impurities to pollute the nitrogen making environment.

[0066] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A single-tower nitrogen production device, characterized in that: include: An air compressor (1), wherein an input end of the air compressor (1) is connected to the outside world; A filter assembly (2), the filter assembly (2) being connected to the output end of the air compressor (1) to filter out impurities in the air output by the air compressor (1); An adsorption tower (3), wherein the number of the adsorption tower (3) is one, the adsorption tower (3) is provided with a nitrogen production inlet and a nitrogen production outlet, a nitrogen production molecular sieve is provided in the adsorption tower (3) and is located between the nitrogen production inlet and the nitrogen production outlet, the nitrogen production inlet is communicated with the output end of the filter component (2) and is communicated with the outside through a first valve (301); A buffer tank (4), the buffer tank (4) being provided with a buffer inlet and a buffer outlet, the buffer inlet being in communication with the nitrogen production outlet; A reflux pipe (5), the reflux pipe (5) being arranged between the adsorption tower (3) and the buffer tank (4), and the reflux pipe (5) being provided with a reflux valve (501); A nitrogen storage tank (6) is provided with a nitrogen storage inlet and a nitrogen storage outlet, and the nitrogen storage inlet is communicated with the buffer outlet.

2. The single-tower nitrogen production device according to claim 1, characterized in that: The reflux valve (501) is a ball valve.

3. The single-tower nitrogen production device according to claim 1, characterized in that: Both ends of the reflux pipe (5) are respectively connected to the nitrogen production outlet and the buffer inlet.

4. The single-tower nitrogen production device according to claim 1, characterized in that: The buffer outlet is connected to a gas purity analyzer (7), a second valve (8) is provided between the buffer outlet and the nitrogen gas storage inlet, the buffer outlet is connected to the outside through a third valve (9), or the buffer outlet is connected to the input end of the air compressor (1) through the third valve (9).

5. The single-tower nitrogen production device according to claim 4, characterized in that: The buffer outlet is connected to the input end of the air compressor (1) through a third valve (9).

6. The single-tower nitrogen production device according to claim 5, characterized in that: The third valve (9) is a proportional valve.

7. The single-tower nitrogen production device according to any one of claims 1 to 6, characterized in that: One end of the first valve (301) away from the adsorption tower (3) is connected to a muffler (302).

8. The single-tower nitrogen production device according to any one of claims 1 to 6, characterized in that: The filter assembly (2) comprises at least two filters (201) connected in sequence, and the filter (201) is connected to a first sewage valve (202).

9. The single-tower nitrogen production device according to claim 8, characterized in that: The filter assembly (2) further comprises a cold dryer (203), wherein the cold dryer (203) is connected between two of the filters (201).

10. The single-tower nitrogen production device according to any one of claims 1 to 6, characterized in that: An air storage tank (11) is also provided between the output end of the air compressor (1) and the filter assembly (2).

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