Multi-tower pressure swing adsorption test device and pressure swing adsorption method

Abstract

The present invention relates to the field of gas separation, and specifically to a multi-tower pressure swing adsorption test device and a pressure swing adsorption method, including a gas supply unit, a purification unit, and a regeneration unit; the purification unit includes an adsorption tower, the gas supply unit leads to the bottom of the adsorption tower, a product gas valve is arranged at the top of the adsorption tower, and a decomposition valve is arranged at the bottom of the adsorption tower; the regeneration unit includes a first pressure equalizing tank, a second pressure equalizing tank, and a regeneration device, the first pressure equalizing tank is connected to the top of the adsorption tower, and the second pressure equalizing tank is connected to the bottom of the adsorption tower, the regeneration device can regenerate the adsorption tower, and the pressure swing adsorption method includes the following steps: adsorption, pressure drop, decomposition, regeneration, pressure rise, and final charging. The advantages of the present invention are: this scheme uses an adsorption tower in conjunction with a first pressure equalizing tank and a second pressure equalizing tank to simulate a multi-tower PSA cycle process to purify helium, and while obtaining the same purity and recovery rate, the production cost of multiple towers is greatly reduced.

Description

Technical Field

[0001] The invention relates to the field of gas separation, and in particular to a multi-tower pressure swing adsorption test device and a pressure swing adsorption method. Background Art

[0002] Helium is a precious rare gas with a wide range of applications in industry and research. At present, helium resources mainly rely on separation from natural gas, which contains 1 vol% to 8 vol% helium. The helium content is low, and the extraction is difficult and costly. Therefore, it is urgent to study new solutions to extract low-content helium from natural gas, improve the purity and recovery rate of extracted helium, and reduce the cost of purification equipment. Summary of the invention

[0003] The technical problem to be solved by the present invention is: how to ensure the purity and recovery rate of helium extraction while reducing the cost of the purification device in the prior art.

[0004] The present invention solves the above technical problems through the following technical means: a multi-tower pressure swing adsorption test device, including a gas supply unit, a purification unit, and a regeneration unit;

[0005] The purification unit comprises an adsorption tower, the gas supply unit leads to the bottom of the adsorption tower, a product gas valve is arranged at the top of the adsorption tower, and a desorption valve is arranged at the bottom of the adsorption tower;

[0006] The regeneration unit includes a first pressure equalizing tank, a second pressure equalizing tank, and a regeneration device. The first pressure equalizing tank is connected to the top of the adsorption tower, and the second pressure equalizing tank is connected to the bottom of the adsorption tower. The regeneration device can regenerate the adsorption tower.

[0007] In the actual application of a multi-tower pressure swing adsorption test device in the present invention, the gas supply unit provides the raw gas to enter the adsorption tower, and the adsorption tower undergoes the following processes: adsorption, pressure drop, analysis, regeneration, pressure rise, and final filling. Here, only the adsorption tower undergoes the above process, because the first pressure equalizing tank and the second pressure equalizing tank are simulated adsorption towers, so there is no need to repeat this step. The specific process is as follows:

[0008] Adsorption: The raw gas is adsorbed and separated under a certain working pressure in the adsorption tower. The top product gas valve is opened and pure helium is collected to complete the purpose of gas adsorption separation and purification. The pressure swing adsorption process uses the different adsorption forces of different adsorbents on the adsorbent to achieve gas separation. Compared with other separation technologies such as low-temperature condensation adsorption and membrane separation, it has the advantages of low energy consumption, no need for heating during bed regeneration, simple equipment, easy operation and maintenance, full automation, stability and reliability, etc.

[0009] Pressure drop equalization: After the adsorbent is saturated, the pressure equalization process begins. The connecting pipeline between the second pressure equalizing tank and the bottom of the adsorption tower is closed, and the adsorption tower performs pressure drop equalization on the first pressure equalizing tank. If there are multiple first pressure equalizing tanks, the adsorption tower performs pressure drop equalization on the first pressure equalizing tanks in sequence. Subsequently, the pipeline between the adsorption tower and the first pressure equalizing tank is closed, and the adsorption tower performs pressure drop equalization on the second pressure equalizing tank.

[0010] Analysis: Open the analysis valve at the bottom of the adsorption tower to analyze the adsorbent and reduce the pressure of the adsorption tower to normal pressure;

[0011] Regeneration: Use the regeneration device to fully regenerate the adsorption tower;

[0012] Pressure equalization: After the regeneration work is completed, the adsorption tower performs a pressure equalization process, the pipeline between the adsorption tower and the first pressure equalization tank is closed, and the second pressure equalization tank performs a pressure equalization on the adsorption tower. Then, the connecting pipeline between the second pressure equalization tank and the bottom of the adsorption tower is closed, and the first pressure equalization tank performs a pressure equalization on the adsorption tower. If there are multiple first pressure equalization tanks, the first pressure equalization tanks perform pressure equalization on the adsorption tower in turn, and the order of the pressure equalization of each first pressure equalization tank is opposite to the order of the pressure drop;

[0013] Final filling: Use product helium for final filling to restore the adsorption tower to the working pressure and prepare for the next adsorption work.

[0014] This solution uses an adsorption tower in conjunction with the first and second pressure equalizing tanks to simulate a multi-tower PSA cycle process to purify helium. While obtaining the same purity and recovery rate, the production cost of the multi-towers is greatly reduced. Since each tower in the multi-tower pressure swing adsorption cycle executes the same sequence of steps, but each step differs by only one phase, the single-tower system only needs to execute one sequence of steps. The logical control of the system is simpler than that of the multi-tower process, and different pressure equalizing tanks can be removed to simulate 4-tower, 3-tower and other PSA cycle helium purification processes. The pressure swing adsorption technology is used to achieve gas separation at normal temperature and low pressure. It has the characteristics of miniaturization, low energy consumption, high reliability, full automation and low maintenance cost.

[0015] The optimization also includes a monitoring unit, which can monitor the gas supply unit, the purification unit, and the regeneration unit.

[0016] The monitoring unit is set up to monitor and record all data of the entire system to ensure normal operation.

[0017] Optimally, the gas supply unit includes a helium gas cylinder, a nitrogen gas cylinder, and a methane gas cylinder respectively leading to the bottom of the adsorption tower;

[0018] A first flow controller is arranged between the helium cylinder and the adsorption tower;

[0019] A second flow controller is arranged between the nitrogen cylinder and the adsorption tower;

[0020] A third flow controller is arranged between the methane gas cylinder and the adsorption tower.

[0021] By controlling different gas cylinders through various flow controllers, raw gases with different components can be simulated according to a certain mixing ratio to meet work requirements.

[0022] Optimally, a temperature detection device and a pressure detection device are provided on the adsorption tower.

[0023] Optimally, at least two first pressure equalizing tanks are provided, and all first pressure equalizing tanks are connected in parallel to the top of the adsorption tower.

[0024] The different numbers of the first pressure equalizing tanks can enable the entire system to simulate pressure swing adsorption operations with different numbers of towers, which has a wider range of applications and lower costs than multi-tower pressure swing adsorption with the same number of towers in the prior art.

[0025] Optimally, pressure detection devices are provided on the first pressure equalizing tank and the second pressure equalizing tank.

[0026] Optimally, the regeneration device includes a vacuum pump connected to the bottom of the adsorption tower.

[0027] Optimally, the regeneration device includes a downstream gas buffer tank connected to the top of the adsorption tower.

[0028] Optimized, also includes gas analyzer;

[0029] A first three-way stopcock is arranged between the adsorption tower and the first pressure equalizing tank, and a first flowmeter is arranged between the first three-way stopcock and the gas analyzer;

[0030] A second three-way stopcock is arranged between the adsorption tower and the second pressure equalizing tank, and a second flow meter is arranged between the second three-way stopcock and the gas analyzer.

[0031] The flow meter and gas analyzer can detect the output volume, purity, and composition of the purified impurity gas of pure helium, thereby efficiently obtaining the helium recovery rate.

[0032] The present invention also discloses a pressure swing adsorption method using the multi-tower pressure swing adsorption test device, comprising the following steps:

[0033] A. Adsorption: Control the gas supply unit to provide raw gas into the adsorption tower, where the raw gas is adsorbed and separated. Open the top product gas valve to collect pure helium to complete gas adsorption separation and purification.

[0034] B. Pressure drop: After the adsorbent is saturated, the pressure drop process begins. The connecting pipeline between the second pressure-equalizing tank and the bottom of the adsorption tower is closed, and the adsorption tower performs pressure drop on the first pressure-equalizing tank. If there are multiple first pressure-equalizing tanks, the adsorption tower performs pressure drop on the first pressure-equalizing tanks in sequence. Subsequently, the pipeline between the adsorption tower and the first pressure-equalizing tank is closed, and the adsorption tower performs pressure drop on the second pressure-equalizing tank.

[0035] C. Analysis: Open the analysis valve at the bottom of the adsorption tower to analyze the adsorbent, so that the pressure of the adsorption tower drops to normal pressure;

[0036] D. Regeneration: Use the regeneration device to completely regenerate the adsorption tower;

[0037] E. Pressure equalization: After the regeneration work is completed, the adsorption tower performs a pressure equalization process, the pipeline between the adsorption tower and the first pressure equalization tank is closed, and the second pressure equalization tank performs a pressure equalization on the adsorption tower. Then, the connecting pipeline between the second pressure equalization tank and the bottom of the adsorption tower is closed, and the first pressure equalization tank performs a pressure equalization on the adsorption tower. If there are multiple first pressure equalization tanks, the first pressure equalization tanks perform pressure equalization on the adsorption tower in turn, and the order of the pressure equalization of each first pressure equalization tank is opposite to the order of the pressure drop;

[0038] F. Final filling: Use product helium for final filling to restore the adsorption tower to the working pressure and prepare for the next adsorption work.

[0039] The advantages of the present invention are:

[0040] 1. In the actual application of a multi-tower pressure swing adsorption test device of the present invention, the gas supply unit provides the raw gas to enter the adsorption tower, and the adsorption tower undergoes the following processes: adsorption, pressure drop, analysis, regeneration, pressure rise, and final filling. Here, only the adsorption tower undergoes the above process. Because the first pressure equalizing tank and the second pressure equalizing tank are simulated adsorption towers, there is no need to repeat this step. The specific process is as follows:

[0041] Adsorption: The raw gas is adsorbed and separated under a certain working pressure in the adsorption tower. The top product gas valve is opened and pure helium is collected to complete the purpose of gas adsorption separation and purification. The pressure swing adsorption process uses the different adsorption forces of different adsorbents on the adsorbent to achieve gas separation. Compared with other separation technologies such as low-temperature condensation adsorption and membrane separation, it has the advantages of low energy consumption, no need for heating during bed regeneration, simple equipment, easy operation and maintenance, full automation, stability and reliability, etc.

[0042] Pressure drop equalization: After the adsorbent is saturated, the pressure equalization process begins. The connecting pipeline between the second pressure equalizing tank and the bottom of the adsorption tower is closed, and the adsorption tower performs pressure drop equalization on the first pressure equalizing tank. If there are multiple first pressure equalizing tanks, the adsorption tower performs pressure drop equalization on the first pressure equalizing tanks in sequence. Subsequently, the pipeline between the adsorption tower and the first pressure equalizing tank is closed, and the adsorption tower performs pressure drop equalization on the second pressure equalizing tank.

[0043] Analysis: Open the analysis valve at the bottom of the adsorption tower to analyze the adsorbent and reduce the pressure of the adsorption tower to normal pressure;

[0044] Regeneration: Use the regeneration device to fully regenerate the adsorption tower;

[0045] Pressure equalization: After the regeneration work is completed, the adsorption tower performs a pressure equalization process, the pipeline between the adsorption tower and the first pressure equalization tank is closed, and the second pressure equalization tank performs a pressure equalization on the adsorption tower. Then, the connecting pipeline between the second pressure equalization tank and the bottom of the adsorption tower is closed, and the first pressure equalization tank performs a pressure equalization on the adsorption tower. If there are multiple first pressure equalization tanks, the first pressure equalization tanks perform pressure equalization on the adsorption tower in turn, and the order of the pressure equalization of each first pressure equalization tank is opposite to the order of the pressure drop;

[0046] Final filling: Use product helium for final filling to restore the adsorption tower to the working pressure and prepare for the next adsorption work.

[0047] This solution uses an adsorption tower in conjunction with the first and second pressure equalizing tanks to simulate a multi-tower PSA cycle process to purify helium. While obtaining the same purity and recovery rate, the production cost of the multi-towers is greatly reduced. Since each tower in the multi-tower pressure swing adsorption cycle executes the same sequence of steps, but each step differs by only one phase, the single-tower system only needs to execute one sequence of steps. The logical control of the system is simpler than that of the multi-tower process, and different pressure equalizing tanks can be removed to simulate 4-tower, 3-tower and other PSA cycle helium purification processes. The pressure swing adsorption technology is used to achieve gas separation at normal temperature and low pressure. It has the characteristics of miniaturization, low energy consumption, high reliability, full automation and low maintenance cost.

[0048] 2. The monitoring unit is set up to monitor and record all data of the entire system to ensure the normal operation.

[0049] 3. By controlling different gas cylinders through various flow controllers, raw gases with different components can be simulated according to a certain mixing ratio to meet work requirements.

[0050] 4. The different number of first pressure equalizing tanks can enable the entire system to simulate different numbers of towers for pressure swing adsorption operations, which has a wider range of applications and lower cost than multi-tower pressure swing adsorption with the same number of towers in the prior art.

[0051] 5. The flow meter and gas analyzer can detect the output volume, purity, and composition of the purified impurity gas of pure helium, thereby efficiently obtaining the helium recovery rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a block diagram of the composition of a multi-tower pressure swing adsorption test device in an embodiment of the present invention;

[0053] Figure 2 This is a schematic diagram of a multi-tower pressure swing adsorption test device in Example 1 of the present invention (vacuum regeneration simulation 5 towers);

[0054] Figure 3 Schematic diagram of a multi-tower pressure swing adsorption test device in Example 2 of the present invention (vacuum regeneration simulation 4 towers);

[0055] Figure 4 This is a schematic diagram of a multi-tower pressure swing adsorption test device in Example 3 of the present invention (vacuum regeneration simulation 3 towers);

[0056] Figure 5 Schematic diagram of a multi-tower pressure swing adsorption test device in Example 4 of the present invention (flushing and regeneration simulation 5 towers);

[0057] in,

[0058] Gas supply unit-101, purification unit-102, regeneration unit-103, monitoring unit-104;

[0059] Helium gas cylinder-1, nitrogen gas cylinder-2, methane gas cylinder-3, first flow controller-4, second flow controller-5, third flow controller-6, product gas valve-7, adsorption tower-8, first three-way stopcock-9, first pressure equalizing tank-10, forward discharge buffer tank-11;

[0060] The first flow meter-13, the second flow meter-14, the gas analyzer-15, the computer-16, the second pressure equalizing tank-17, the second three-way stopcock-18, the vacuum pump-19, and the analytical valve-20. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are 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.

[0062] Embodiment 1:

[0063] like Figure 1 As shown, a multi-tower pressure swing adsorption test device includes a gas supply unit 101, a purification unit 102, a regeneration unit 103, and a monitoring unit 104.

[0064] like Figure 2As shown, the gas supply unit 101 includes a helium gas cylinder 1, a nitrogen gas cylinder 2, and a methane gas cylinder 3 which are respectively connected to the bottom of the adsorption tower 8. The gas cylinders of the gas supply unit 101 can be flexibly adjusted to different types according to actual needs to meet actual requirements.

[0065] A first flow controller 4 is arranged between the helium cylinder 1 and the adsorption tower 8 .

[0066] A second flow controller 5 is arranged between the nitrogen cylinder 2 and the adsorption tower 8 .

[0067] A third flow controller 6 is arranged between the methane gas cylinder 3 and the adsorption tower 8 .

[0068] like Figure 2 As shown, preferably, corresponding valves are arranged downstream of the first flow controller 4 , the second flow controller 5 , and the third flow controller 6 , and the first flow controller 4 , the second flow controller 5 , and the third flow controller 6 are all connected to the monitoring unit 104 .

[0069] like Figure 2 As shown, the purification unit 102 includes an adsorption tower 8, on which a temperature detection device and a pressure detection device are arranged. The temperature detection device adopts a thermocouple. In this embodiment, a total of eight thermocouples are arranged from bottom to top in the adsorption tower 8, and the pressure detection device adopts a pressure sensor. Both the thermocouple and the pressure sensor are connected to the monitoring unit 104.

[0070] like Figure 2 As shown, the gas supply unit 101 leads to the bottom of the adsorption tower 8, and a product gas valve 7 is arranged on the top of the adsorption tower 8. The product gas valve 7 adopts a needle valve. The product gas valve 7 is connected to the junction of the helium gas cylinder 1, the nitrogen gas cylinder 2, and the methane gas cylinder 3. A decomposition valve 20 is arranged at the bottom of the adsorption tower 8, and the decomposition valve 20 adopts a needle valve.

[0071] like Figure 2 As shown, the regeneration unit 103 includes a first pressure equalizing tank 10, a second pressure equalizing tank 17, and a regeneration device. The first pressure equalizing tank 10 is connected to the top of the adsorption tower 8. At least two first pressure equalizing tanks 10 are provided. In this embodiment, three first pressure equalizing tanks 10 are provided. All first pressure equalizing tanks 10 are connected in parallel to the top of the adsorption tower 8, and corresponding valves are provided between the junction of the three first pressure equalizing tanks 10 and each first pressure equalizing tank 10.

[0072] like Figure 2As shown, the second pressure equalizing tank 17 is connected to the bottom of the adsorption tower 8, and the first pressure equalizing tank 10 and the second pressure equalizing tank 17 are both provided with a pressure detection device, the pressure detection device uses a pressure sensor, and the pressure sensor is connected to the monitoring unit 104, and the regeneration device can regenerate the adsorption tower 8. In this embodiment, the regeneration device includes a vacuum pump 19 connected to the bottom of the adsorption tower 8.

[0073] like Figure 2 As shown, the monitoring unit 104 can monitor the gas supply unit 101 , the purification unit 102 , and the regeneration unit 103 . In this embodiment, the monitoring unit 104 uses a computer 16 .

[0074] like Figure 2 As shown, the device further comprises a gas analyzer 15 .

[0075] A first three-way stopcock 9 is arranged between the adsorption tower 8 and the first pressure equalizing tank 10, and a first end of the first three-way stopcock 9 is connected to between the product gas valve 7 and the adsorption tower 8, and a second end of the first three-way stopcock 9 is connected to the confluence of the three first pressure equalizing tanks 10, and a first flowmeter 13 is arranged between the third end of the first three-way stopcock 9 and the gas analyzer 15.

[0076] like Figure 2 As shown, a second three-way stopcock 18 is provided between the adsorption tower 8 and the second pressure-equalizing tank 17, and the first three-way stopcock 9 and the second three-way stopcock 18 are preferably pneumatic valves, so as to facilitate intelligent control according to the use requirements of the system. A valve corresponding to the second pressure-equalizing tank 17 is provided between the second three-way stopcock 18 and the second pressure-equalizing tank 17, and the vacuum pump 19 is connected between the second three-way stopcock 18 and the valve, a valve is provided upstream of the vacuum pump 19, and a second flowmeter 14 is provided between the second three-way stopcock 18 and the gas analyzer 15.

[0077] The first flow meter 13 , the second flow meter 14 , and the gas analyzer 15 are all connected to the computer 16 .

[0078] The present invention also discloses a pressure swing adsorption method using the multi-tower pressure swing adsorption test device, comprising the following steps:

[0079] A. Adsorption: Control the gas supply unit 101 to provide the raw gas to enter the adsorption tower 8, the raw gas is adsorbed and separated in the adsorption tower 8, the top product gas valve 7 is opened, and the pure helium is collected to complete the gas adsorption separation and purification;

[0080] B. Pressure drop: After the adsorbent is saturated, the pressure drop process is started, and the connecting pipeline between the second pressure-equalizing tank 17 and the bottom of the adsorption tower 8 is closed. Specifically, the second three-way stopcock 18 is closed, and the first three-way stopcock 9 is opened. The adsorption tower 8 performs a pressure drop on the first pressure-equalizing tank 10. If there are multiple first pressure-equalizing tanks 10, the adsorption tower 8 performs a pressure drop on the first pressure-equalizing tank 10 in sequence, and the first flowmeter 13 records the flow rate. The gas analyzer 15 connected to the rear end records the components of the pressure-equalizing gas. Subsequently, the pipeline between the adsorption tower 8 and the first pressure-equalizing tank 10 is closed, and the adsorption tower 8 performs a pressure drop on the second pressure-equalizing tank 17. Specifically, the first three-way stopcock 9 is closed, and the second three-way stopcock 18 is opened. The second flowmeter 14 records the flow rate, and the gas analyzer 15 connected to the rear end records the components of the pressure-equalizing gas;

[0081] C. Analysis: Open the analysis valve 20 at the bottom of the adsorption tower 8 to analyze the adsorbent, so that the pressure of the adsorption tower 8 drops to normal pressure;

[0082] D. Regeneration: The adsorption tower 8 is completely regenerated by using a regeneration device. Specifically, the vacuum pump 19 is turned on to perform vacuum analysis. The second flow meter 14 records the flow rate of the analysis gas. The gas analyzer 15 connected at the rear end records the components of the analysis gas, so that the adsorbent is completely regenerated and the regeneration of the adsorption tower 8 is completed.

[0083] E. Pressure equalization: After the regeneration work is completed, the adsorption tower 8 performs a pressure equalization process, and the pipeline between the adsorption tower 8 and the first pressure equalizing tank 10 is closed. Specifically, the first three-way stopcock 9 is closed, and the second three-way stopcock 18 is opened. The second pressure equalizing tank 17 performs a pressure equalization on the adsorption tower 8. Subsequently, the connecting pipeline between the second pressure equalizing tank 17 and the bottom of the adsorption tower 8 is closed. Specifically, the second three-way stopcock 18 at the bottom is closed, and the first three-way stopcock 9 is opened. The first pressure equalizing tank 10 performs a pressure equalization on the adsorption tower 8. If there are multiple first pressure equalizing tanks 10, the first pressure equalizing tanks 10 perform pressure equalization on the adsorption tower 8 in turn, and the order of the pressure equalization of each first pressure equalizing tank 10 is opposite to the order of the pressure equalization drop;

[0084] F. Final filling: Use product helium to perform final filling, so that the adsorption tower 8 returns to the working pressure and prepares for the next adsorption work.

[0085] Working principle:

[0086] like Figure 1 , 2 As shown, in actual application of a multi-tower pressure swing adsorption test device in the present invention, the gas supply unit 101 provides raw gas to enter the adsorption tower 8, and the computer 16 controls the first flow controller 4, the second flow controller 5, and the third flow controller 6 to adjust the proportion of different gases entering.

[0087] The adsorption tower 8 undergoes the following process: adsorption, pressure drop, analysis, regeneration, pressure rise, and final charging. Here, only the adsorption tower 8 undergoes the above process. Because the first pressure equalizing tank 10 and the second pressure equalizing tank 17 are simulated adsorption towers, there is no need to repeat this step. The specific process is as follows:

[0088] Adsorption: The raw gas is adsorbed and separated under a certain working pressure in the adsorption tower 8, and the top product gas valve 7 is opened to collect pure helium to achieve the purpose of gas adsorption separation and purification. The pressure swing adsorption process uses the different adsorption forces of different adsorbents on the adsorbent to achieve gas separation. Compared with other separation technologies such as low-temperature condensation adsorption and membrane separation, it has the advantages of low energy consumption, no need for heating during bed regeneration, simple equipment, easy operation and maintenance, full automation, stability and reliability, etc.

[0089] Pressure drop: After the adsorbent is saturated, the pressure drop process begins. The connecting pipeline between the second pressure-equalizing tank 17 and the bottom of the adsorption tower 8 is closed. Specifically, the second three-way stopcock 18 is closed, and the first three-way stopcock 9 is opened. The adsorption tower 8 performs a pressure drop on the first pressure-equalizing tank 10. If there are multiple first pressure-equalizing tanks 10, the adsorption tower 8 performs a pressure drop on the first pressure-equalizing tank 10 in sequence. The first flowmeter 13 records the flow rate, and the gas analyzer 15 connected to the rear end records the components of the pressure-equalizing gas. Subsequently, the pipeline between the adsorption tower 8 and the first pressure-equalizing tank 10 is closed, and the adsorption tower 8 performs a pressure drop on the second pressure-equalizing tank 17. Specifically, the first three-way stopcock 9 is closed, and the second three-way stopcock 18 is opened. The second flowmeter 14 records the flow rate, and the gas analyzer 15 connected to the rear end records the components of the pressure-equalizing gas.

[0090] Analysis: Open the analysis valve 20 at the bottom of the adsorption tower 8 to analyze the adsorbent, so that the pressure of the adsorption tower 8 drops to normal pressure;

[0091] Regeneration: The adsorption tower 8 is completely regenerated by using a regeneration device. Specifically, the vacuum pump 19 is turned on to perform vacuum analysis. The second flow meter 14 records the flow rate of the analysis gas. The gas analyzer 15 connected at the rear end records the components of the analysis gas. The adsorbent is completely regenerated, and the regeneration of the adsorption tower 8 is completed.

[0092] Pressure equalization: After the regeneration work is completed, the adsorption tower 8 performs a pressure equalization process, and the pipeline between the adsorption tower 8 and the first pressure equalizing tank 10 is closed. Specifically, the first three-way stopcock 9 is closed, and the second three-way stopcock 18 is opened. The second pressure equalizing tank 17 performs a pressure equalization on the adsorption tower 8. Subsequently, the connecting pipeline between the second pressure equalizing tank 17 and the bottom of the adsorption tower 8 is closed. Specifically, the second three-way stopcock 18 at the bottom is closed, and the first three-way stopcock 9 is opened. The first pressure equalizing tank 10 performs a pressure equalization on the adsorption tower 8. If there are multiple first pressure equalizing tanks 10, the first pressure equalizing tanks 10 perform pressure equalization on the adsorption tower 8 in turn, and the order of the pressure equalization of each first pressure equalizing tank 10 is opposite to the order of the pressure equalization drop;

[0093] Final filling: Use product helium for final filling, so that the adsorption tower 8 returns to the working pressure and prepares for the next adsorption work.

[0094] This solution utilizes an adsorption tower 8 in conjunction with a first pressure equalizing tank 10 and a second pressure equalizing tank 17 to simulate a multi-tower PSA cycle process to purify helium. While obtaining the same purity and recovery rate, the production cost of the multi-towers is greatly reduced. Since each tower in the multi-tower pressure swing adsorption cycle executes the same sequence of steps, but each step differs by only one phase, the single-tower system only needs to execute one sequence of steps, and the logical control of the system is simpler than that of the multi-tower process. This embodiment can simulate a 5-tower PSA cycle helium purification process, and different pressure equalizing tanks can be removed to simulate 4-tower, 3-tower, and other PSA cycle helium purification processes. The pressure swing adsorption technology is used to achieve gas separation at normal temperature and low pressure. It has the characteristics of miniaturization, low energy consumption, high reliability, full automation, and low maintenance cost.

[0095] Embodiment 2:

[0096] The difference between this embodiment and the first embodiment is that:

[0097] like Figure 3 As shown, in this embodiment, two first pressure equalizing tanks 10 are provided.

[0098] Embodiment three:

[0099] The difference between this embodiment and the first embodiment is that:

[0100] like Figure 4 As shown, in this embodiment, one first pressure equalizing tank 10 is provided.

[0101] Embodiment 4:

[0102] The difference between this embodiment and the first embodiment is that:

[0103] like Figure 5As shown, the regeneration device includes a forward-discharge buffer tank 11 connected to the top of the adsorption tower 8. Specifically, the vacuum pump 19 is eliminated, the forward-discharge buffer tank 11 is connected to the junction between the first three-way stopcock 9 and the three first pressure equalizing tanks 10, and a valve is set at the forward-discharge buffer tank 11.

[0104] This embodiment adopts flushing regeneration, which is different from the vacuum regeneration method in that the adsorption tower 8 undergoes the following processes: adsorption, equal pressure drop, forward placement, reverse placement, flushing, equal pressure increase, and final filling.

[0105] Pressure equalization: After the adsorbent is saturated, the pressure equalization process begins. Close the second three-way stopcock 18 at the bottom, open the first three-way stopcock 9, and the adsorption tower 8 performs one, two, and three pressure equalization drops on the three first pressure equalizing tanks 10 in turn. The first flowmeter 13 connected to the first three-way stopcock 9 records the flow rate, and the gas analyzer 15 connected to the rear end records the components of the pressure equalization gas.

[0106] Then close the first three-way stopcock 9, open the second three-way stopcock 18, and the adsorption tower 8 continues to perform four equalizing pressure drops on the second pressure equalizing tank 17. The second flowmeter 14 connected to the second three-way stopcock 18 records the flow rate, and the gas analyzer 15 connected at the rear end records the components of the pressure equalizing gas.

[0107] Forward discharge, reverse discharge, flushing: Then put the remaining small amount of gas into the forward discharge buffer tank 11, the first flowmeter 13 records the forward discharge flow rate, and the gas analyzer 15 connected at the rear end records the components of the forward discharge gas. Then open the bottom analysis valve 20 to analyze the adsorbent, so that the pressure of the adsorption tower 8 drops to normal pressure, and then put the gas in the forward discharge buffer tank 11 into the adsorption tower 8 for flushing, so that the adsorbent is completely regenerated and the regeneration of the adsorption tower 8 is completed.

[0108] Pressure equalization: After the regeneration work is completed, the adsorption tower 8 performs a pressure equalization process, the first three-way stopcock 9 is closed, the second three-way stopcock 18 is opened, the second pressure equalizing tank 17 performs a pressure equalization on the adsorption tower 8, and then the second three-way stopcock 18 at the bottom is closed, the first three-way stopcock 9 is opened, and the three first pressure equalizing tanks 10 perform a second, three, and four times of pressure equalization on the adsorption tower 8 in turn. The order of the pressure equalization of the three first pressure equalizing tanks 10 is opposite to the order of the pressure equalization.

[0109] Final filling: The product helium is then used for final filling, so that the adsorption tower 8 returns to the working pressure and is ready for the next adsorption work.

[0110] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-tower pressure swing adsorption test device, characterized in that: It comprises a gas supply unit (101), a purification unit (102), a regeneration unit (103), and a monitoring unit (104), wherein the monitoring unit (104) is capable of monitoring the gas supply unit (101), the purification unit (102), and the regeneration unit (103); The purification unit (102) comprises an adsorption tower (8), the gas supply unit (101) leads to the bottom of the adsorption tower (8), a product gas valve (7) is arranged at the top of the adsorption tower (8), and a desorption valve (20) is arranged at the bottom of the adsorption tower (8); The regeneration unit (103) comprises a first pressure-equalizing tank (10), a second pressure-equalizing tank (17), and a regeneration device, wherein the first pressure-equalizing tank (10) is connected to the top of the adsorption tower (8), and the second pressure-equalizing tank (17) is connected to the bottom of the adsorption tower (8), and the regeneration device is capable of regenerating the adsorption tower (8); the regeneration device comprises a vacuum pump (19) connected to the bottom of the adsorption tower (8) and a downstream gas buffer tank (11) connected to the top of the adsorption tower (8); a temperature detection device and a pressure detection device are provided on the adsorption tower (8); The first pressure equalizing tank (10) and the second pressure equalizing tank (17) are both provided with pressure detection devices; they also include a gas analyzer (15); a first three-way stopcock (9) is provided between the adsorption tower (8) and the first pressure equalizing tank (10), and a first flowmeter (13) is provided between the first three-way stopcock (9) and the gas analyzer (15); a second three-way stopcock (18) is provided between the adsorption tower (8) and the second pressure equalizing tank (17), and a second flowmeter (14) is provided between the second three-way stopcock (18) and the gas analyzer (15).

2. The multi-tower pressure swing adsorption test device according to claim 1, characterized in that: The gas supply unit (101) comprises a helium gas cylinder (1), a nitrogen gas cylinder (2), and a methane gas cylinder (3) which are respectively connected to the bottom of the adsorption tower (8); A first flow controller (4) is arranged between the helium cylinder (1) and the adsorption tower (8); A second flow controller (5) is provided between the nitrogen cylinder (2) and the adsorption tower (8); A third flow controller (6) is provided between the methane gas cylinder (3) and the adsorption tower (8).

3. The multi-tower pressure swing adsorption test device according to claim 1, characterized in that: At least two of the first pressure equalizing tanks (10) are provided, and all the first pressure equalizing tanks (10) are connected in parallel to the top of the adsorption tower (8).

4. A pressure swing adsorption method using the multi-tower pressure swing adsorption test device according to any one of claims 1 to 3, characterized in that: The steps include: A. Adsorption: Control the gas supply unit (101) to provide raw gas to enter the adsorption tower (8), the raw gas is adsorbed and separated in the adsorption tower (8), the top product gas valve (7) is opened, pure helium is collected, and gas adsorption separation and purification are completed; B. Pressure drop equalization: after the adsorbent is saturated, the pressure equalization process is started, the connecting pipeline between the second pressure equalizing tank (17) and the bottom of the adsorption tower (8) is closed, and the adsorption tower (8) performs pressure drop equalization on the first pressure equalizing tank (10). If there are multiple first pressure equalizing tanks (10), the adsorption tower (8) performs pressure drop equalization on the first pressure equalizing tanks (10) in sequence, and then the pipeline between the adsorption tower (8) and the first pressure equalizing tank (10) is closed, and the adsorption tower (8) performs pressure drop equalization on the second pressure equalizing tank (17); C. Analysis: Open the analysis valve (20) at the bottom of the adsorption tower (8) to analyze the adsorbent, so that the pressure of the adsorption tower (8) drops to normal pressure; D. Regeneration: using a regeneration device to completely regenerate the adsorption tower (8); E. Pressure equalization: After the regeneration work is completed, the adsorption tower (8) performs a pressure equalization process, the pipeline between the adsorption tower (8) and the first pressure equalization tank (10) is closed, and the second pressure equalization tank (17) performs a pressure equalization on the adsorption tower (8). Subsequently, the connecting pipeline between the second pressure equalization tank (17) and the bottom of the adsorption tower (8) is closed, and the first pressure equalization tank (10) performs a pressure equalization on the adsorption tower (8). If there are multiple first pressure equalization tanks (10), the first pressure equalization tanks (10) perform a pressure equalization on the adsorption tower (8) in sequence, and the order of the pressure equalization of each first pressure equalization tank (10) is opposite to the order of the pressure equalization; F. Final filling: The product helium is used for final filling to restore the adsorption tower (8) to the working pressure and prepare for the next adsorption operation.

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