Helium isotope low-temperature adsorption separation system and method

Abstract

The invention provides a helium isotope low-temperature adsorption separation system and method, and relates to the technical field of isotope separation. The helium isotope low-temperature adsorption separation system comprises an adsorption column, a low-temperature control unit, an adsorbent regeneration unit, a helium isotope gas outlet control unit, a helium isotope gas inlet and recovery control unit and a system purging replacement unit, the low-temperature control unit comprises a refrigerating machine, a vacuum cover, a first-stage cold screen, a second-stage cold screen, a first-stage anti-radiation screen, a second-stage anti-radiation screen, an air inlet pipe and an air outlet pipe, the first-stage anti-radiation screen is arranged in the vacuum cover, the first-stage cold screen is arranged at an opening of the first-stage anti-radiation screen, and a mounting hole is formed in the first-stage cold screen. The helium isotope low-temperature adsorption separation system provided by the invention has the characteristics of accurate temperature control in a wide temperature area, accurate adsorption pressure control, high rewarming desorption speed, high adsorption efficiency and gas recoverability, is simple in structure and convenient to operate, and has great significance in separation research of helium isotopes.

Description

Technical Field

[0001] The present invention relates to the technical field of isotope separation, and in particular to a helium isotope low-temperature adsorption separation system and method. Background Art

[0002] There are two relatively stable isotopes of helium: 3 He and 4 He. Helium-3( 3 He) is a rare stable helium isotope, whose abundance in nature is much lower than that of helium-4 ( 4 He). Despite its relative scarcity, helium-3 has attracted much attention due to its unique physical properties and application potential. In particular, the demand for high-purity helium-3 isotopes is increasing in the fields of low-temperature physics, superfluid research, nuclear fusion reactors, and medical imaging (such as magnetic resonance imaging, MRI).

[0003] In recent years, the scientific community has seen a surge in demand for high-purity helium-3, which plays a key role in a variety of high-tech applications. For example, in nuclear fusion experiments, helium-3 can be used as a fuel to promote cleaner and safer energy production. In cryogenic technology, a mixture of helium-3 and helium-4 exhibits superfluid behavior, which provides an important platform for the study of basic physics.

[0004] However, due to the extremely low natural abundance of helium-3, traditional methods of obtaining it often cannot meet the demand for high-purity helium-3. Therefore, it is particularly important to develop effective helium-3 separation technology. 4 He cooled standard cold traps can easily remove 4 All impurities except He. 4 He impurities are usually 3 He - 4 He mixture is distilled to remove. However, this method 4 The He consumption is very high, and the equipment required for this process is also very difficult to produce and operate. Summary of the invention

[0005] The present invention provides a helium isotope cryogenic adsorption separation system to solve the problems of complex operation and liquid separation in the existing separation system. 4 The problem of high He consumption.

[0006] The present invention provides a helium isotope low-temperature adsorption separation system, comprising: Adsorption column; A low-temperature control unit, comprising a refrigerator, a vacuum cover, a primary cold screen, a secondary cold screen, a primary radiation shield, a secondary radiation shield, an air inlet pipe and an air outlet pipe, wherein the primary radiation shield is arranged inside the vacuum cover, the primary cold screen is arranged at the opening of the primary radiation shield, and the primary cold screen is provided with a mounting hole; the secondary radiation shield is arranged inside the primary radiation shield, the secondary cold screen is arranged at the opening of the secondary radiation shield, and the secondary cold screen is provided with a mounting hole; the refrigerator sequentially penetrates the mounting holes of the primary cold screen and the secondary cold screen, the adsorption column is arranged on the inner surface of the secondary cold screen, the air inlet pipe is communicated with the inlet of the adsorption column, and the air outlet pipe is communicated with the outlet of the adsorption column; an adsorbent regeneration unit, the adsorbent regeneration unit being used to store the desorbed gas; A helium isotope gas outlet control unit is connected to the outlet pipe and the adsorbent regeneration unit, and the helium isotope gas outlet control unit is used to contain the separated and purified helium isotope gas; A helium isotope gas intake and recovery control unit is connected to the intake pipe and the adsorbent regeneration unit, and the helium isotope gas intake and recovery control unit is used to store the raw gas to be separated and recover the gas after the experiment; The system purge replacement unit is connected to the helium isotope gas outlet control unit, the adsorbent regeneration unit and the helium isotope gas inlet and recovery control unit, and is used to evacuate the helium isotope low-temperature adsorption separation system and perform purge replacement.

[0007] According to a helium isotope low-temperature adsorption separation system provided by the present invention, the air inlet pipe is provided with an adsorption column inlet valve, and the air outlet pipe is provided with an adsorption column outlet valve.

[0008] According to a helium isotope low-temperature adsorption separation system provided by the present invention, the helium isotope gas outlet control unit comprises a plurality of helium isotope gas outlet control components, a first pipeline, a second pipeline and a first vortex dry pump, the plurality of helium isotope gas outlet control components are arranged in parallel between the first pipeline and the second pipeline, the helium isotope gas outlet control component comprises a purification tank, a first pressure gauge, a first sampling tank, a purification gas tank inlet valve and a purification gas tank outlet valve, the inlet of the purification tank is connected to the first pipeline through the purification gas tank inlet valve, the outlet of the purification tank is connected to the first end of the second pipeline through the purification gas tank outlet valve, the first pressure gauge is connected to the purification tank through the first pressure gauge side valve, the first sampling tank is connected to the purification tank through the first sampling valve; the first pipeline is connected to the outlet pipe through the first vortex dry pump, and the second end of the second pipeline is connected to the adsorbent regeneration unit and the system purge replacement unit.

[0009] According to a helium isotope low-temperature adsorption separation system provided by the present invention, the helium isotope gas outlet control unit also includes a vortex dry pump outlet valve, a vortex dry pump inlet valve, a bypass valve and a first drain valve, the vortex dry pump outlet valve is arranged at the outlet of the first vortex dry pump, the vortex dry pump inlet valve is arranged at the inlet of the first vortex dry pump, the inlet of the bypass valve is connected to the inlet of the vortex dry pump inlet valve, and the outlet of the bypass valve and the inlet of the first drain valve are both connected to the outlet of the vortex dry pump outlet valve.

[0010] According to a helium isotope low-temperature adsorption separation system provided by the present invention, the adsorbent regeneration unit includes a desorption gas tank, a second pressure gauge, a second sampling tank, a desorption gas tank outlet valve, a desorption gas tank inlet valve, a second vortex dry pump and a heating resistor, the inlet of the desorption gas tank is connected to the outlet of the second vortex dry pump through the desorption gas tank inlet valve, the inlet of the second vortex dry pump is connected to the outlet pipe through the desorption branch, and the second end of the second pipeline is connected to the inlet of the second vortex dry pump; the outlet of the desorption gas tank is connected to the second pipeline through the desorption gas tank outlet valve, the second pressure gauge is connected to the desorption gas tank through the second pressure gauge side valve, the second sampling tank is connected to the desorption gas tank through the second sampling valve, and the heating resistor is arranged on the adsorption column.

[0011] According to a helium isotope low-temperature adsorption separation system provided by the present invention, a first desorption branch valve is provided at one end of the desorption branch close to the second scroll dry pump, and a second desorption branch valve is provided at one end of the desorption branch away from the second scroll dry pump.

[0012] According to a helium isotope cryogenic adsorption separation system provided by the present invention, the system purge replacement unit comprises a vacuum pump, 4 He gas cylinder, a first helium purge branch, a second helium purge branch, a third helium purge branch, a helium purge main valve and a vacuum branch, wherein the first end of the first helium purge branch and the second helium purge branch are connected to the vacuum branch through the helium purge main valve. 4 The gas outlet of the He gas cylinder is connected, the second end of the first helium purge branch is connected to the first pipeline, and the second end of the second helium purge branch is connected to the inlet of the second vortex dry pump; the second helium purge branch is connected to the adsorption column inlet valve through the third helium purge branch, and the third helium purge branch is provided with a flow controller, an air intake control valve and a third helium purge branch valve; the first end of the vacuum branch is connected to the vacuum cover, the second end of the vacuum branch is connected to the third helium purge branch, and the vacuum pump is connected to the vacuum branch through the vacuum main valve.

[0013] According to a helium isotope low-temperature adsorption separation system provided by the present invention, the vacuum branch between the vacuum main valve and the vacuum cover is provided with a first vacuum branch valve, the vacuum branch between the vacuum main valve and the third helium purge branch is provided with a third vacuum branch valve, and the vacuum branch between the vacuum main valve and the third vacuum branch valve is connected to the first helium purge branch through a second vacuum branch valve.

[0014] According to a helium isotope low-temperature adsorption separation system provided by the present invention, the helium isotope gas intake and recovery control unit comprises a raw gas tank, a third pressure gauge, a third sampling tank, a second drain valve, a first recovery trunk valve, a second recovery trunk valve, a raw gas tank inlet and outlet valves and a recovery trunk, the third pressure gauge is connected to the raw gas tank through a third pressure gauge side valve, and the third sampling tank is connected to the raw gas tank through a third sampling valve; the first end of the recovery trunk is connected to the inlet of the raw gas tank through the raw gas tank inlet and outlet valves, the second end of the recovery trunk is connected to the second drain valve, the recovery trunk between the raw gas tank inlet and outlet valves and the second drain valve is connected to the outlet of the second vortex dry pump and the third helium purge branch, the first recovery trunk valve is arranged on the recovery trunk between the raw gas tank inlet and outlet valves and the second drain valve, and the second recovery trunk valve is arranged at the second end of the second pipeline.

[0015] The present invention also provides a helium isotope cryogenic adsorption separation method, the separation method is based on any of the above-mentioned helium isotope cryogenic adsorption separation systems, the separation method comprising: Step S10, performing leak detection operations on various components and pipelines of the separation system, and assembling the separation system; Step S20, open all valves except the first drain valve, the second drain valve, the first vacuum branch valve and the helium purge main valve, control the vacuum pump to start, vacuumize the interior of the separation system to 10Pa, and then close the vacuum main valve; open the helium purge main valve to allow high-purity 4He to enter the separation system, when the air pressure inside the separation system is 90Kpa, close the helium purge main valve, open the vacuum main valve to vacuumize the interior of the separation system to 10Pa, and then close all valves except the first pressure gauge side valve, the second pressure gauge side valve, and the third pressure gauge side valve; Step S30, controlling the first scroll dry pump and the second scroll dry pump to start, and opening the scroll dry pump outlet valve, the scroll dry pump inlet valve, the first drain valve, the second desorption branch valve, the second drain valve, the first desorption branch valve, the helium purge main valve, and the second helium purge branch valve to allow high-purity helium to enter the separation system for purge, and replace the interior of the scroll dry pump; after the predetermined purge time, controlling the first scroll dry pump, the second scroll dry pump, and the valve to close; Step S40, after repeating step S30 for a first predetermined number of times, closing all valves except the first pressure gauge side valve, the second pressure gauge side valve, and the third pressure gauge side valve; Step S50, opening the vacuum main valve and the first vacuum branch valve to evacuate the vacuum cover, and when the pressure in the vacuum cover is lower than 1.0E-1, controlling the refrigerator to start to cool down; Step S60, when the adsorption column reaches a predetermined temperature, the inlet valve of the first purified gas tank, the bypass valve, the inlet valve of the adsorption column, the outlet valve of the adsorption column, the air intake control valve and the inlet and outlet valves of the raw gas tank are opened, and the gas flow rate and the adsorption pressure of the adsorption column are controlled by the flow controller, so that the raw gas enters the first purified gas tank after being adsorbed and separated by the adsorption column; when the pressure inside the first purified gas tank is stable, the inlet valve of the first purified gas tank, the bypass valve, the air intake control valve and the inlet and outlet valves of the raw gas tank are closed, and the inlet valve of the second purified gas tank, the outlet valve of the vortex dry pump, the inlet valve of the first purified gas tank, the outlet valve of the second vortex dry pump ... A vortex dry pump and a vortex dry pump inlet valve are provided to pump the residual gas in the adsorption column and the pipeline into the second purified gas tank. When the pressure inside the second purified gas tank is stable, the second purified gas tank inlet valve is closed, and the third purified gas tank inlet valve and the air intake control valve and the raw gas tank inlet and outlet valves are opened; when the pressure inside the third purified gas tank is stable, the third purified gas tank inlet valve, the adsorption column inlet valve, the adsorption column outlet valve, the vortex dry pump outlet valve, the first vortex dry pump, the vortex dry pump inlet valve and the air intake control valve and the raw gas tank inlet and outlet valves are closed; Step S70, opening the first sampling valves of the first purified gas tank, the second purified gas tank and the third purified gas tank to perform sampling, and closing the first sampling valves of the first purified gas tank, the second purified gas tank and the third purified gas tank and the refrigerator after the sampling is completed; Step S80, opening the adsorption column outlet valve, the second desorption branch valve, the first desorption branch valve and the desorption gas tank inlet valve, and controlling the second vortex dry pump and the heating resistor to turn on, desorbing the adsorbent of the adsorption column, and pumping the desorbed gas into the desorption gas tank; when the pressure inside the desorption gas tank is stable, closing the adsorption column outlet valve, the second desorption branch valve, the first desorption branch valve, the desorption gas tank inlet valve, the second vortex dry pump and the heating resistor; Step S90, opening the second sampling valve to sample the gas inside the desorption gas tank, and closing the second sampling valve after the sampling is completed; Step S100, opening the first purified gas tank outlet valve, the second purified gas tank outlet valve, the third purified gas tank outlet valve, the desorption gas tank outlet valve, the first recovery trunk valve, the second recovery trunk valve and the raw gas tank inlet and outlet valves, and controlling the second vortex dry pump to start, pumping the gas inside the first purified gas tank, the second purified gas tank, the second purified gas tank and the desorption gas tank into the raw gas tank, and after the pressure inside the raw gas tank is stable, closing the first purified gas tank outlet valve, the second purified gas tank outlet valve, the third purified gas tank outlet valve, the desorption gas tank outlet valve, the first recovery trunk valve, the second recovery trunk valve, the raw gas tank inlet and outlet valves and the second vortex dry pump; Step S110, opening the third sampling valve to sample the gas inside the raw gas tank, and closing the third sampling valve after the sampling is completed; Step S120, after repeating step S30 for a second predetermined number of times, all valves except the first pressure gauge side valve, the second pressure gauge side valve, and the third pressure gauge side valve and the vacuum pump are closed.

[0016] The helium isotope low-temperature adsorption separation system provided by the present invention has the characteristics of precise temperature control in a wide temperature range, precise control of adsorption pressure, fast re-temperature desorption speed, high adsorption efficiency, and gas recovery. It has a simple structure and is easy to operate, and is of great significance for the separation research of helium isotopes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic structural diagram of the helium isotope low-temperature adsorption separation system provided by the present invention.

[0019] Reference numerals: 1. First sampling valve; 2. First sampling tank; 3. First pressure gauge; 4. First pressure gauge side valve; 5. Third purification gas tank inlet valve; 6. Second purification gas tank inlet valve; 7. First purification gas tank inlet valve; 8. Third purification gas tank outlet valve; 9. Second purification gas tank outlet valve; 10. First purification gas tank outlet valve; 10a. First pipeline; 10b. Second pipeline; 11. Third purification gas tank; 12. Second purification gas tank; 13. First purification gas tank; 14. Helium replacement valve; 15. Vortex dry pump outlet valve; 1 6. First vortex dry pump; 17. Inlet valve of vortex dry pump; 18. Bypass valve; 19. First exhaust valve; 20. Inlet valve of adsorption column; 21. Outlet valve of adsorption column; 22a. Desorption branch; 22. Second desorption branch valve; 23. Refrigerator; 23a. Inlet pipe; 24a. Outlet pipe; 24. Temperature controller; 25. Vacuum cover; 26. First-level cold screen; 27. First-level radiation shield; 28. Second-level cold screen; 29. ​​Second-level radiation shield; 30. Adsorption column; 31. Heating resistor; 32. Flow controller; 33. Desorption gas tank ; 33a, second pressure gauge; 33b, second pressure gauge side valve; 33c, second sampling tank; 33d, second sampling valve; 34, desorption tank outlet valve; 35, desorption tank inlet valve; 36, second emptying valve; 37, second vortex dry pump; 38, first desorption branch valve; 39, intake control valve; 40, first recovery trunk valve; 40a, recovery trunk; 41, second recovery trunk valve; 42, third helium purge branch valve; 43, raw gas tank inlet and outlet valves; 44, raw gas tank; 44a, third pressure pressure gauge; 44b, third pressure gauge side valve; 44c, third sampling tank; 44d, third sampling valve; 45, vacuum pump; 45a, first helium purge branch; 45b, second helium purge branch; 45c, third helium purge branch; 45d, vacuum branch; 46, vacuum main valve; 47, first vacuum branch valve; 48, second vacuum branch valve; 49, third vacuum branch valve; 50, first helium purge branch valve; 51, helium purge main valve; 52, second helium purge branch valve; 53, 4 Heating cylinders. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings 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.

[0021] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0022] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0023] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0024] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0025] like Figure 1As shown, the helium isotope low-temperature adsorption separation system includes an adsorption column 30, a low-temperature control unit, an adsorbent regeneration unit, a helium isotope gas outlet control unit, a helium isotope gas inlet and recovery control unit and a system purge replacement unit. The low-temperature control unit includes a refrigerator 23, a vacuum cover 25, a primary cold screen 26, a secondary cold screen 28, a primary radiation shield 27, a secondary radiation shield 29, an inlet pipe 23a and an outlet pipe 24a. The adsorption column 30 is mainly used to contain the adsorbent. The adsorption column 30 is provided with two channels, one outlet and one inlet. The adsorbent inside the adsorption column 30 includes a single component or a multi-component mixture of zeolite molecular sieves, activated carbon, coconut shells, metal organic frameworks (MOFs), and covalent organic frameworks (COFs).

[0026] The primary radiation shield 27 is arranged inside the vacuum cover 25, the primary cold shield 26 is arranged at the opening of the primary radiation shield 27, and the primary cold shield 26 is provided with a mounting hole; the secondary radiation shield 29 is arranged inside the primary radiation shield 27, the secondary cold shield 28 is arranged at the opening of the secondary radiation shield 29, and the secondary cold shield 28 is provided with a mounting hole; the refrigerator 23 passes through the mounting holes of the primary cold shield 26 and the secondary cold shield 28 in sequence, and the adsorption column 30 is arranged on the inner surface of the secondary cold shield 28. Since the adsorption column 30 is located on the inner surface of the secondary cold shield 28, the loss of cold can be reduced through the two-stage radiation shield. The air inlet pipe 23a is connected to the inlet of the adsorption column 30, and the air outlet pipe 24a is connected to the outlet of the adsorption column 30; the adsorbent regeneration unit is used to store the desorbed gas, and the air inlet pipe 23a is heat-settled at the connection with the primary cold shield 26 to reduce external heat interference.

[0027] The helium isotope gas outlet control unit is connected to the outlet pipe 24a and the adsorbent regeneration unit, and the helium isotope gas outlet control unit is used to accommodate the separated and purified helium isotope gas. The helium isotope gas intake and recovery control unit is connected to the intake pipe 23a and the adsorbent regeneration unit, and the helium isotope gas intake and recovery control unit is used to store the raw gas to be separated and recover the gas after the experiment.

[0028] The system purge replacement unit is connected with the helium isotope gas outlet control unit, the adsorbent regeneration unit and the helium isotope gas inlet and recovery control unit. The system purge replacement unit is used to evacuate the helium isotope low-temperature adsorption separation system and perform purge replacement.

[0029] Furthermore, the primary cold screen 26, the secondary cold screen 28 and the adsorption column 30 are all provided with temperature sensors, and the low temperature control unit also includes a temperature controller 24. The above temperature sensors are all electrically connected to the temperature controller 24, and the controllable temperature range of the temperature controller 24 is 4.2K-300K.

[0030] The helium isotope low-temperature adsorption separation system provided by the present invention has the characteristics of precise temperature control in a wide temperature range, precise control of adsorption pressure, fast re-temperature desorption speed, high adsorption efficiency, and gas recovery. It has a simple structure and is easy to operate, and is of great significance for the separation research of helium isotopes.

[0031] In one embodiment of the present invention, the air inlet pipe 23a is provided with an adsorption column inlet valve 20, and the air outlet pipe 24a is provided with an adsorption column outlet valve 21. Specifically, the adsorption column inlet valve 20 is located at one end of the air inlet pipe 23a away from the adsorption column 30, and the adsorption column outlet valve 21 is located at one end of the air outlet pipe 24a away from the adsorption column 30.

[0032] In one embodiment of the present invention, a helium isotope gas outlet control unit includes a plurality of helium isotope gas outlet control components, a first pipeline 10a, a second pipeline 10b and a first vortex dry pump 16. The plurality of helium isotope gas outlet control components are arranged in parallel between the first pipeline 10a and the second pipeline 10b. The helium isotope gas outlet control components include a purification tank, a first pressure gauge 3, a first sampling tank 2, a purification gas tank inlet valve and a purification gas tank outlet valve. The purification gas tank is used to contain the separated and purified helium isotope gas. The first vortex dry pump 16 is used to provide power to the system pipeline. The inlet of the purification tank is connected to the first pipeline 10a through the purified gas tank inlet valve, the outlet of the purification tank is connected to the first end of the second pipeline 10b through the purified gas tank outlet valve, the first pressure gauge 3 is connected to the purification tank through the first pressure gauge side valve 4, and the first sampling tank 2 is connected to the purification tank through the first sampling valve 1; the first pipeline 10a is connected to the outlet pipe 24a through the first vortex dry pump 16, and the second end of the second pipeline 10b is connected to the adsorbent regeneration unit and the system purge and replacement unit.

[0033] In a specific embodiment of the present invention, the helium isotope gas outlet control unit includes three helium isotope gas outlet control components. Of course, the number of helium isotope gas outlet control components is not limited thereto, and two, four or more can also be set. For the convenience of description, the purification gas tanks of the three helium isotope gas outlet control components are respectively recorded as: the first purification gas tank 13, the second purification gas tank 12, and the third purification gas tank 11. Similarly, the purification gas tank inlet valves of the three purification gas tanks are respectively recorded as: the first purification gas tank inlet valve 7, the second purification gas tank inlet valve 6, and the third purification gas tank inlet valve 5. The purification gas tank outlet valves of the three purification gas tanks are respectively recorded as: the first purification gas tank outlet valve 10, the second purification gas tank outlet valve 9, and the third purification gas tank outlet valve 8.

[0034] In one embodiment of the present invention, the helium isotope gas outlet control unit also includes a vortex dry pump outlet valve 15, a vortex dry pump inlet valve 17, a bypass valve 18 and a first drain valve 19. The vortex dry pump outlet valve 15 is arranged at the outlet of the first vortex dry pump 16, and the vortex dry pump inlet valve 17 is arranged at the inlet of the first vortex dry pump 16. When the vortex dry pump outlet valve 15 and the vortex dry pump inlet valve 17 are opened at the same time, the first vortex dry pump 16 is connected to the system pipeline, the inlet of the bypass valve 18 is connected to the inlet of the vortex dry pump inlet valve 17, the outlet of the bypass valve 18 and the inlet of the first drain valve 19 are both connected to the outlet of the vortex dry pump outlet valve 15, and the bypass valve 18 is used to control the conduction and closing of the bypass pipeline.

[0035] In one embodiment of the present invention, the adsorbent regeneration unit includes a desorption gas tank 33, a second pressure gauge 33a, a second sampling tank 33c, a desorption gas tank outlet valve 34, a desorption gas tank inlet valve 35, a second vortex dry pump 37 and a heating resistor 31, the desorption gas tank 33 is used to contain the desorption gas, the inlet of the desorption gas tank 33 is connected to the outlet of the second vortex dry pump 37 through the desorption gas tank inlet valve 35, the second vortex dry pump 37 is used to provide power to the system pipeline, and the inlet of the second vortex dry pump 37 is connected to the desorption branch 2 2a is connected to the outlet pipe 24a, and the second end of the second pipeline 10b is connected to the inlet of the second vortex dry pump 37; the outlet of the desorption gas tank 33 is connected to the second pipeline 10b through the desorption gas tank outlet valve 34, the second pressure gauge 33a is connected to the desorption gas tank 33 through the second pressure gauge side valve 33b, and the second sampling tank 33c is connected to the desorption gas tank 33 through the second sampling valve 33d. The heating resistor 31 is arranged on the adsorption column 30, and the heating resistor 31 is used to heat the adsorption column 30 and thereby increase the adsorbent regeneration rate.

[0036] In one embodiment of the present invention, a first desorption branch valve 38 is provided at one end of the desorption branch 22a close to the second scroll dry pump 37, and a second desorption branch valve 22 is provided at one end of the desorption branch 22a away from the second scroll dry pump 37. The first desorption branch valve 38 cooperates with the second desorption branch valve 22 to control the conduction and closing of the desorption branch 22a. When the first desorption branch valve 38 and the second desorption branch valve 22 are both in an open state, the desorption branch 22a connects the inlet of the second scroll dry pump 37 with the outlet pipe 24a.

[0037] In one embodiment of the present invention, the system purge replacement unit includes a vacuum pump 45, 4 The first ends of the first helium purge branch 45a and the second helium purge branch 45b are connected to the vacuum branch 45d through the helium purge main valve 51.4 The gas outlet of the He gas bottle 53 is connected, the second end of the first helium purge branch 45a is connected to the first pipeline 10a, and the second end of the second helium purge branch 45b is connected to the inlet of the second vortex dry pump 37; the second helium purge branch 45b is connected to the adsorption column inlet valve 20 through the third helium purge branch 45c, and the third helium purge branch 45c is provided with a flow controller 32, an air intake control valve 39 and a third helium purge branch valve 42; the first end of the vacuum branch 45d is connected to the vacuum cover 25, the second end of the vacuum branch 45d is connected to the third helium purge branch 45c, and the vacuum pump 45 is connected to the vacuum branch 45d through the vacuum main valve 46, and the vacuum pump 45 is used to evacuate the system pipeline to avoid contamination by impurity gases; 4 The He gas cylinder 53 is used for purging and replacing after the system is vacuumed, and the flow controller 32 is used to control the gas flow rate and thus the adsorption pressure.

[0038] In one embodiment of the present invention, the vacuum branch 45d between the vacuum main valve 46 and the vacuum cover 25 is provided with a first vacuum branch valve 47, the vacuum branch 45d between the vacuum main valve 46 and the third helium purge branch 45c is provided with a third vacuum branch valve 49, and the vacuum branch 45d between the vacuum main valve 46 and the third vacuum branch valve 49 is connected to the first helium purge branch 45a through the second vacuum branch valve 48.

[0039] Furthermore, a first helium purge branch 45a valve is provided at the first end of the first helium purge branch 45a, a helium replacement valve 14 is provided at the second end of the first helium purge branch 45a, and a second helium purge branch 45b valve is provided at the second end of the second helium purge branch 45b.

[0040] In one embodiment of the present invention, the helium isotope gas intake and recovery control unit includes a raw gas tank 44, a third pressure gauge 44a, a third sampling tank 44c, a second drain valve 36, a first recovery trunk valve 40, a second recovery trunk valve 41, a raw gas tank inlet and outlet valves 43 and a recovery trunk 40a, the raw gas tank 44 contains raw gas to be separated, the third pressure gauge 44a is connected to the raw gas tank 44 through a third pressure gauge side valve 44b, and the third sampling tank 44c is connected to the raw gas tank 44 through a third sampling valve 44d; the recovery The first end of the trunk line 40a is connected to the inlet of the raw gas tank 44 through the raw gas tank inlet and outlet valves 43, the second end of the recovery trunk line 40a is connected to the second exhaust valve 36, the recovery trunk line 40a between the raw gas tank inlet and outlet valves 43 and the second exhaust valve 36 is connected to the outlet of the second vortex dry pump 37 and the third helium purge branch 45c, the first recovery trunk line valve 40 is arranged on the recovery trunk line 40a between the raw gas tank inlet and outlet valves 43 and the second exhaust valve 36, and the second recovery trunk line valve 41 is arranged at the second end of the second pipeline 10b.

[0041] The present invention further provides a helium isotope cryogenic adsorption separation method, the separation method is based on the helium isotope cryogenic adsorption separation system described in any one of the above embodiments, and the separation method comprises: Step S10, performing leak detection operations on various components and pipelines of the separation system, and assembling the separation system; The steps of leak testing the components and pipelines of the separation system and assembling the separation system include: Step S11, before the separation operation, the first purified gas tank 13, the second purified gas tank 12, the third purified gas tank 11, the desorption gas tank 33 and the raw gas tank 44 need to be leak tested, and the above tanks are respectively connected to a helium leak detection mass spectrometer, and the tank welds and the pipeline KF connection are leak tested by spraying helium in a vacuum mode. If the leakage rate is lower than 1.0E-9 after spraying helium, it means there is no leakage; Step S12, perform leak detection on all external pipelines in sections. It should be noted that the pipeline of the adsorption column 30 is leak detected at room temperature to avoid bending the gas pipeline when installing components such as the refrigerator 23. After the leak detection is completed, the separation system is assembled.

[0042] Step S20, open all valves except the first evacuation valve 19, the second evacuation valve 36, the first vacuum branch valve 47 and the helium purge main valve 51, control the vacuum pump 45 to start the separation system to evacuate the interior to 10Pa, and then close the vacuum main valve 46; open the helium purge main valve 51 to allow high-purity 4He to enter the separation system, when the air pressure inside the separation system is 90Kpa, close the helium purge main valve 51, open the vacuum main valve 46 to evacuate the interior of the separation system to 10Pa, and then close all valves except the first pressure gauge side valve 4, the second pressure gauge side valve 33b, and the third pressure gauge side valve 44b; Step S30, controlling the first scroll dry pump 16 and the second scroll dry pump 37 to start, and opening the scroll dry pump outlet valve 15, the scroll dry pump inlet valve 17, the first drain valve 19, the second desorption branch valve 22, the second drain valve 36, the first desorption branch valve 38, the helium purge main valve 51, and the second helium purge branch valve 52 to allow high-purity helium to enter the separation system for purge, and replace the interior of the scroll dry pump; after the predetermined purge time, controlling the first scroll dry pump 16, the second scroll dry pump 37 and the valves to close; It should be noted here that the scheduled time is 2-3 minutes. Of course, the range of the scheduled time is not limited thereto and is determined according to actual needs.

[0043] Step S40, after repeating step S30 for a first predetermined number of times, close all valves except the first pressure gauge side valve 4, the second pressure gauge side valve 33b, and the third pressure gauge side valve 44b; It should be noted here that the first predetermined number of times is 2-3 times. Of course, the range of the first predetermined number of times is not limited thereto and is determined according to actual needs.

[0044] Step S50, opening the vacuum main valve 46 and the first vacuum branch valve 47 to evacuate the vacuum cover 25, and when the pressure in the vacuum cover 25 is lower than 1.0E-1, controlling the refrigerator 23 to start cooling; It should be noted that during the vacuuming process, when the resistance gauge of the vacuum pump 45 shows that the pressure is lower than 1.0E-1, the molecular pump and the ionization gauge are turned on, and when the ionization gauge shows that the pressure is lower than 1.0E-3, the refrigerator 23 can be turned on for cooling.

[0045] Step S60, when the adsorption column 30 reaches a predetermined temperature, the first purified gas tank inlet valve 7, the bypass valve 18, the adsorption column inlet valve 20, the adsorption column outlet valve 21, the air intake control valve 39 and the raw gas tank inlet and outlet valves 43 are opened, and the gas flow rate and the adsorption pressure of the adsorption column 30 are controlled by the flow controller 32, so that the raw gas enters the first purified gas tank 13 after being adsorbed and separated by the adsorption column 30; when the pressure inside the first purified gas tank 13 is stable, the first purified gas tank inlet valve 7, the bypass valve 18, the air intake control valve 39 and the raw gas tank inlet and outlet valves 43 are closed, and the second purified gas tank inlet valve 6, the vortex dry pump outlet valve 1 are opened. 5. The first vortex dry pump 16 and the vortex dry pump inlet valve 17 are used to pump the adsorption column 30 and the residual gas in the pipeline into the second purified gas tank 12. When the pressure inside the second purified gas tank 12 is stable, the second purified gas tank inlet valve 6 is closed, and the third purified gas tank inlet valve 5 and the air intake control valve 39 and the raw gas tank inlet and outlet valves 43 are opened; when the pressure inside the third purified gas tank 11 is stable, the third purified gas tank inlet valve 5, the adsorption column inlet valve 20, the adsorption column outlet valve 21, the vortex dry pump outlet valve 15, the first vortex dry pump 16, the vortex dry pump inlet valve 17, the air intake control valve 39 and the raw gas tank inlet and outlet valves 43 are closed; Step S70, opening the first sampling valve 1 of the first purified gas tank 13, the second purified gas tank 12 and the third purified gas tank 11 to perform sampling, and after the sampling is completed, closing the first sampling valve 1 of the first purified gas tank 13, the second purified gas tank 12, the third purified gas tank 11 and the refrigerator 23; Step S80, open the adsorption column outlet valve 21, the second desorption branch valve 22, the first desorption branch valve 38 and the desorption gas tank inlet valve 35, and control the second vortex dry pump 37 and the heating resistor 31 to open, desorb the adsorbent of the adsorption column 30, and pump the desorbed gas into the desorption gas tank 33; when the pressure inside the desorption gas tank 33 is stable, close the adsorption column outlet valve 21, the second desorption branch valve 22, the first desorption branch valve 38, the desorption gas tank inlet valve 35, the second vortex dry pump 37 and the heating resistor 31; Step S90, opening the second sampling valve 33d to sample the gas inside the desorption gas tank 33, and closing the second sampling valve 33d after the sampling is completed; Step S100, open the first purified gas tank outlet valve 10, the second purified gas tank outlet valve 9, the third purified gas tank outlet valve 8, the desorption gas tank outlet valve 34, the first recovery trunk valve 40, the second recovery trunk valve 41 and the raw gas tank inlet and outlet valves 43, and control the second vortex dry pump 37 to start, pump the gas inside the first purified gas tank 13, the second purified gas tank 12, the second purified gas tank 12 and the desorption gas tank 33 into the raw gas tank 44, and after the pressure inside the raw gas tank 44 is stable, close the first purified gas tank outlet valve 10, the second purified gas tank outlet valve 9, the third purified gas tank outlet valve 8, the desorption gas tank outlet valve 34, the first recovery trunk valve 40, the second recovery trunk valve 41, the raw gas tank inlet and outlet valves 43 and the second vortex dry pump 37; Step S110, opening the third sampling valve 44d to sample the gas inside the raw gas tank 44, and closing the third sampling valve 44d after the sampling is completed; Step S120, after repeating step S30 for a second predetermined number of times, all valves and the vacuum pump 45 are closed except the first pressure gauge side valve 4, the second pressure gauge side valve 33b, and the third pressure gauge side valve 44b.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. 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 helium isotope cryogenic adsorption separation system, characterized in that: include: Adsorption column (30); A low-temperature control unit, comprising a refrigerator (23), a vacuum cover (25), a primary cold screen (26), a secondary cold screen (28), a primary radiation shield (27), a secondary radiation shield (29), an air inlet pipe (23a) and an air outlet pipe (24a), wherein the primary radiation shield (27) is arranged inside the vacuum cover (25), the primary cold screen (26) is arranged at an opening of the primary radiation shield (27), and the primary cold screen (26) is provided with a mounting hole; the secondary radiation shield (29) is arranged at the primary Inside the radiation shield (27), the secondary cold shield (28) is arranged at the opening of the secondary radiation shield (29), and the secondary cold shield (28) is provided with a mounting hole; the refrigerator (23) sequentially passes through the mounting holes of the primary cold shield (26) and the secondary cold shield (28), the adsorption column (30) is arranged on the inner surface of the secondary cold shield (28), the air inlet pipe (23a) is communicated with the inlet of the adsorption column (30), and the air outlet pipe (24a) is communicated with the outlet of the adsorption column (30); an adsorbent regeneration unit, the adsorbent regeneration unit being used to store the desorbed gas; a helium isotope gas outlet control unit, which is in communication with the outlet pipe (24a) and the adsorbent regeneration unit, and is used to contain the separated and purified helium isotope gas; a helium isotope gas intake and recovery control unit, which is in communication with the intake pipe (23a) and the adsorbent regeneration unit, and is used to store the raw gas to be separated and to recover the gas after the experiment; The system purge replacement unit is connected to the helium isotope gas outlet control unit, the adsorbent regeneration unit and the helium isotope gas inlet and recovery control unit, and is used to evacuate the helium isotope low-temperature adsorption separation system and perform purge replacement.

2. The helium isotope cryogenic adsorption separation system according to claim 1, characterized in that: The air inlet pipe (23a) is provided with an adsorption column inlet valve (20), and the air outlet pipe (24a) is provided with an adsorption column outlet valve (21).

3. The helium isotope cryogenic adsorption separation system according to claim 2, characterized in that: The helium isotope gas outlet control unit comprises a plurality of helium isotope gas outlet control components, a first pipeline (10a), a second pipeline (10b) and a first scroll dry pump (16); the plurality of helium isotope gas outlet control components are arranged in parallel between the first pipeline (10a) and the second pipeline (10b); the helium isotope gas outlet control components comprise a purification tank, a first pressure gauge (3), a first sampling tank (2), a purification tank inlet valve and a purification tank outlet valve; the inlet of the purification tank is connected to the first purification tank via the purification tank inlet valve. The first pipeline (10a) is connected to the purification tank, the outlet of the purification tank is connected to the first end of the second pipeline (10b) through the purified gas tank outlet valve, the first pressure gauge (3) is connected to the purification tank through the first pressure gauge side valve (4), and the first sampling tank (2) is connected to the purification tank through the first sampling valve (1); the first pipeline (10a) is connected to the air outlet pipe (24a) through the first vortex dry pump (16), and the second end of the second pipeline (10b) is connected to the adsorbent regeneration unit and the system purge replacement unit.

4. The helium isotope cryogenic adsorption separation system according to claim 3, characterized in that: The helium isotope gas outlet control unit further comprises a vortex dry pump outlet valve (15), a vortex dry pump inlet valve (17), a bypass valve (18) and a first drain valve (19); the vortex dry pump outlet valve (15) is arranged at the outlet of the first vortex dry pump (16); the vortex dry pump inlet valve (17) is arranged at the inlet of the first vortex dry pump (16); the inlet of the bypass valve (18) is connected to the inlet of the vortex dry pump inlet valve (17); and the outlet of the bypass valve (18) and the inlet of the first drain valve (19) are both connected to the outlet of the vortex dry pump outlet valve (15).

5. The helium isotope cryogenic adsorption separation system according to claim 3 or 4, characterized in that: The adsorbent regeneration unit comprises a desorption gas tank (33), a second pressure gauge (33a), a second sampling tank (33c), a desorption gas tank outlet valve (34), a desorption gas tank inlet valve (35), a second vortex dry pump (37) and a heating resistor (31); the inlet of the desorption gas tank (33) is connected to the outlet of the second vortex dry pump (37) via the desorption gas tank inlet valve (35); the inlet of the second vortex dry pump (37) is connected to the outlet pipe (24a) via the desorption branch (22a); The second end of the second pipeline (10b) is connected to the inlet of the second vortex dry pump (37); the outlet of the desorption gas tank (33) is connected to the second pipeline (10b) via the desorption gas tank outlet valve (34); the second pressure gauge (33a) is connected to the desorption gas tank (33) via a second pressure gauge side valve; the second sampling tank (33c) is connected to the desorption gas tank (33) via a second sampling valve (33d); and the heating resistor (31) is arranged on the adsorption column (30).

6. The helium isotope cryogenic adsorption separation system according to claim 5, characterized in that: A first desorption branch valve (38) is provided at one end of the desorption branch (22a) close to the second scroll dry pump (37), and a second desorption branch valve (22) is provided at one end of the desorption branch (22a) away from the second scroll dry pump (37).

7. The helium isotope cryogenic adsorption separation system according to claim 6, characterized in that: The system purge replacement unit comprises a vacuum pump (45), 4 A He gas cylinder (53), a first helium purge branch (45a), a second helium purge branch (45b), a third helium purge branch (45c), a helium purge main valve (51) and a vacuum branch (45d), wherein the first ends of the first helium purge branch (45a) and the second helium purge branch (45b) are connected to the helium purge main valve (51) through the helium purge main valve (51). 4 The first helium purge branch (45a) is connected to the gas outlet of the He gas bottle (53); the second end of the first helium purge branch (45a) is connected to the first pipeline (10a); the second end of the second helium purge branch (45b) is connected to the inlet of the second vortex dry pump (37); the second helium purge branch (45b) is connected to the adsorption column inlet valve (20) through the third helium purge branch (45c); the third helium purge branch (45c) is provided with a flow controller (32), an air intake control valve (39) and a third helium purge branch valve (42); the first end of the vacuum branch (45d) is connected to the vacuum cover (25); the second end of the vacuum branch (45d) is connected to the third helium purge branch (45c); the vacuum pump (45) is connected to the vacuum branch (45d) through the vacuum main valve (46).

8. The helium isotope cryogenic adsorption separation system according to claim 7, characterized in that: The vacuum branch line (45d) between the vacuum main line valve (46) and the vacuum cover (25) is provided with a first vacuum branch line valve (47), the vacuum branch line (45d) between the vacuum main line valve (46) and the third helium purge branch line (45c) is provided with a third vacuum branch line valve (49), and the vacuum branch line (45d) between the vacuum main line valve (46) and the third vacuum branch line valve (49) is connected to the first helium purge branch line (45a) via a second vacuum branch line valve (48).

9. The helium isotope cryogenic adsorption separation system according to claim 8, characterized in that: The helium isotope gas intake and recovery control unit comprises a raw gas tank (44), a third pressure gauge (44a), a third sampling tank (44c), a second drain valve (36), a first recovery trunk valve (40), a second recovery trunk valve (41), a raw gas tank inlet and outlet valves (43) and a recovery trunk (40a); the third pressure gauge (44a) is connected to the raw gas tank (44) via a third pressure gauge side valve (44b); the third sampling tank (44c) is connected to the raw gas tank (44) via a third sampling valve (44d); the first end of the recovery trunk (40a) is connected to the raw gas tank inlet and outlet valves (44b) via the third pressure gauge side valve (44b); the third sampling tank (44c) is connected to the raw gas tank (44) via a third sampling valve (44d); the first end of the recovery trunk (40a) is connected to the raw gas tank inlet and outlet valves (44d); 3) is connected to the inlet of the raw gas tank (44), the second end of the recovery trunk line (40a) is connected to the second drain valve (36), the recovery trunk line (40a) between the raw gas tank inlet and outlet valves (43) and the second drain valve (36) is connected to the outlet of the second vortex dry pump (37) and the third helium purge branch line (45c), the first recovery trunk line valve (40) is arranged on the recovery trunk line (40a) between the raw gas tank inlet and outlet valves (43) and the second drain valve (36), and the second recovery trunk line valve (41) is arranged on the second end of the second pipeline (10b).

10. A method for the cryogenic adsorption separation of helium isotopes, the separation method being based on the helium isotope cryogenic adsorption separation system according to any one of claims 1 to 9, characterized in that: The separation method comprises: Step S10, performing leak detection operations on various components and pipelines of the separation system, and assembling the separation system; Step S20, opening all valves except the first evacuation valve (19), the second evacuation valve (36), the first vacuum branch valve (47) and the helium purge main valve (51), controlling the vacuum pump (45) to start evacuating the interior of the separation system to 10 Pa, and then closing the vacuum branch valve (46); opening the helium purge main valve (51) to allow the high-purity 4 He enters the separation system. When the air pressure inside the separation system reaches 90 kPa, the helium purge main valve (51) is closed, and the vacuum main valve (46) is opened to evacuate the interior of the separation system to 10 Pa, and then all valves except the first pressure gauge side valve (4), the second pressure gauge side valve (33b), and the third pressure gauge side valve (44b) are closed; Step S30, controlling the first scroll dry pump (16) and the second scroll dry pump (17) to start, and opening the scroll dry pump outlet valve (15), the scroll dry pump inlet valve (17), the first drain valve (19), the second desorption branch valve (22), the second drain valve (36), the first desorption branch valve (38), the helium purge main valve (51), and the second helium purge branch valve (52) to allow high-purity helium to enter the separation system for purge and replace the interior of the scroll dry pump; after the purge time is predetermined, controlling the first scroll dry pump (16), the second scroll dry pump (17), and the valves to close; Step S40, after repeating step S30 for a first predetermined number of times, closing all valves except the first pressure gauge side valve (4), the second pressure gauge side valve (33b), and the third pressure gauge side valve (44b); Step S50, opening the vacuum main valve (46) and the first vacuum branch valve (47) to evacuate the vacuum cover (25), and when the pressure in the vacuum cover (25) is lower than 1.0E-1, controlling the refrigerator (23) to start cooling; Step S60, when the adsorption column (30) reaches a predetermined temperature, the first purified gas tank inlet valve (7), the bypass valve (18), the adsorption column inlet valve (20), the adsorption column outlet valve (21), the air intake control valve (39) and the raw gas tank inlet and outlet valves (43) are opened, and the gas flow rate and the adsorption pressure of the adsorption column (30) are controlled by the flow controller (32) so that the raw gas enters the first purified gas tank (13) after being adsorbed and separated by the adsorption column (30); when the pressure inside the first purified gas tank (13) is stabilized, the first purified gas tank inlet valve (7), the bypass valve (18), the air intake control valve (39) and the raw gas tank inlet and outlet valves (43) are closed, and the second purified gas tank inlet valve (6), the vortex dry pump outlet valve (15), the first purified gas tank inlet valve (7), the bypass valve (18), the air intake control valve (39) and the raw gas tank inlet and outlet valves (43) are opened. a vortex dry pump (16) and a vortex dry pump inlet valve (17) to pump the adsorption column (30) and the residual gas in the pipeline into the second purified gas tank (12); when the pressure inside the second purified gas tank (12) is stabilized, the second purified gas tank inlet valve (6) is closed, and the third purified gas tank inlet valve (5) and the air intake control valve (39) and the raw material gas tank inlet and outlet valves (43) are opened; when the pressure inside the third purified gas tank (11) is stabilized, the third purified gas tank inlet valve (5), the adsorption column inlet valve (20), the adsorption column outlet valve (21), the vortex dry pump outlet valve (15), the first vortex dry pump (16), the vortex dry pump inlet valve (17), the air intake control valve (39) and the raw material gas tank inlet and outlet valves (43) are closed; Step S70, opening the first sampling valves (1) of the first purified gas tank (13), the second purified gas tank (12) and the third purified gas tank (11) to perform sampling, and after the sampling is completed, closing the first sampling valves (1) of the first purified gas tank (13), the second purified gas tank (12), the third purified gas tank (11) and the refrigerator (23); Step S80, opening the adsorption column outlet valve (21), the second desorption branch valve (22), the first desorption branch valve (38), and the desorption gas tank inlet valve (35), and controlling the second vortex dry pump (37) and the heating resistor (31) to open, desorbing the adsorbent of the adsorption column (30), and pumping the desorbed gas into the desorption gas tank (33); when the pressure inside the desorption gas tank (33) is stabilized, closing the adsorption column outlet valve (21), the second desorption branch valve (22), the first desorption branch valve (38), the desorption gas tank inlet valve (35), the second vortex dry pump (37), and the heating resistor (31); Step S90, opening the second sampling valve (33d) to sample the gas inside the desorption gas tank (33), and closing the second sampling valve (33d) after the sampling is completed; Step S100, opening the first purified gas tank outlet valve (10), the second purified gas tank outlet valve (9), the third purified gas tank outlet valve (8), the desorption gas tank outlet valve (34), the first recovery trunk line valve (40), the second recovery trunk line valve (41), and the raw gas tank inlet and outlet valves (43), and controlling the second scroll dry pump (37) to start, pumping the gas inside the first purified gas tank (13), the second purified gas tank (12), the second purified gas tank (12), and the desorption gas tank (33) into the raw gas tank (44), and after the pressure inside the raw gas tank (44) is stabilized, closing the first purified gas tank outlet valve (10), the second purified gas tank outlet valve (9), the third purified gas tank outlet valve (8), the desorption gas tank outlet valve (34), the first recovery trunk line valve (40), the second recovery trunk line valve (41), the raw gas tank inlet and outlet valves (43), and the second scroll dry pump (37); Step S110, opening the third sampling valve (44d) to sample the gas inside the raw gas tank (44), and closing the third sampling valve (44d) after the sampling is completed; Step S120, after repeating step S30 for a second predetermined number of times, all valves except the first pressure gauge side valve (4), the second pressure gauge side valve (33b), and the third pressure gauge side valve (44b) and the vacuum pump (45) are closed.

Images