Pressure buildup device and pressure buildup method for helium low-temperature purification

Abstract

The invention discloses a pressure buildup device and a pressure buildup method for low-temperature purification of helium. The pressure buildup device comprises a flash evaporation unit, a purification unit and a heat regeneration unit which are connected in sequence. According to the invention, through the arrangement of the pressure buildup device, the product gas of the liquid-air separator can be used for carrying out pressure buildup on the adsorber under regeneration pressure buildup in a medium-high pressure working state, so that the adsorber under the regeneration pressure buildup in the working state is prevented from pressurizing the adsorber under the regeneration pressure buildup, and the pressure of the adsorber under the working state is prevented from being lost; due to the fact that the pressure difference between a liquid-air separator and an adsorber under regeneration pressure buildup is large, middle-high pressure impact is prone to causing equipment damage, meanwhile, the pressure buildup process is conducted in the purification process, the time needed by pressure buildup is shortened, after the adsorber in the working state is saturated, pressure buildup of the adsorber in the regeneration state is completed, automatic switching can be achieved, and the efficiency is improved. And the high-purity helium is continuously produced, so that the use requirement of the high-purity helium is met.

Description

Technical Field

[0001] The present invention relates to the technical field of low-temperature purification of helium, and more particularly to a pressure building device and a pressure building method for low-temperature purification of helium. Background Art

[0002] Adsorption technology is a commonly used means of gas separation and purification, and is widely used in natural gas liquefaction, air separation, rare gas refining and environmental protection fields. Low-temperature adsorption, compared with normal-temperature adsorption, refers to the process of placing adsorbents such as molecular sieves, activated carbon and silica gel in a low-temperature environment far below room temperature, reaching 80K or even 20K, for gas impurity adsorption.

[0003] According to the BET multi-layer molecular isothermal adsorption equation, physical adsorption is an exothermic process. Therefore, when most adsorbents adsorb low-boiling gas impurities, their adsorption capacity will increase exponentially with the decrease of temperature. Therefore, compared with normal-temperature adsorption, low-temperature adsorption has the advantages of large adsorption capacity, saving equipment volume, high adsorption limit, good product purity, and the ability to remove stubborn impurities such as low-boiling points.

[0004] With the continuous development of hydrogen liquefaction, helium liquefaction and rare gas refining technologies, the demand for low-temperature adsorption technology is becoming more and more urgent. However, there are few publicly disclosed equalization processes for adsorption and regeneration at home and abroad at present. Simply using means such as nitrogen purging cannot meet the switching of low-temperature purification devices and ensure the high-purity gas required for industries such as semiconductors with a purity of 99.9999% or more. For example, in the patent document with the publication number CN114291791A, nitrogen is used to purge and regenerate the low-temperature adsorber. Summary of the Invention

[0005] The technical problem to be solved by the present invention is how to meet the continuous gas production and use requirements for high-purity gas.

[0006] The present invention solves the above technical problem by the following technical means: A pressure building device for low-temperature purification of helium, including a flash unit, a purification unit, and a heat regeneration unit connected in sequence. The flash unit is connected to the purification unit through a pressure building device. The pressure building device includes a parallel pressure building pipeline 1 and a pressure building pipeline 2. A control valve is provided on the pressure building pipeline 1, and an orifice plate is provided on the pressure building pipeline 2. Control valves are provided upstream and downstream of the orifice plate. The purification unit includes two groups of adsorbers. Each group of adsorbers includes two series-connected adsorbers. The two groups of adsorbers are respectively connected to the raw gas input pipeline connected to the flash unit through the pressure building device.

[0007] As a preferred technical solution, it further includes a heat exchange unit, which is arranged upstream of the flash evaporation unit. A heat exchange unit inlet valve, a heat exchanger, and a raw material gas pressure gauge are successively arranged on the raw material gas input pipeline. Helium output pipelines are connected to both groups of adsorbers. The helium output pipeline exchanges heat with the raw material gas input pipeline through the heat exchanger, and the gas in the helium output pipeline enters the regenerative heat unit after heat exchange.

[0008] As a preferred technical solution, the flash evaporation unit includes a liquid air separator inlet pipeline, and a flash evaporation unit inlet valve, a liquid air separator pressure gauge, and a liquid air separation cylinder successively arranged on the liquid air separator inlet pipeline. The liquid air separation cylinder can flash-separate the impurity gas in the raw material gas and cause the separated raw material gas to enter the purification unit.

[0009] As a preferred technical solution, the regenerative heat unit includes a regenerative heat pipeline, and a regenerative heat unit inlet valve, a regenerative heat unit, and a regenerative heat unit outlet valve arranged on the regenerative heat pipeline.

[0010] As a preferred technical solution, a pressure relief pipeline is further connected to the regenerative heat pipeline upstream of the regenerative heat unit outlet valve. An airbag is connected to the downstream of the pressure relief pipeline, and a pressure relief valve is arranged on the pressure relief pipeline.

[0011] As a preferred technical solution, an analysis unit is further connected downstream of the regenerative heat unit. The analysis unit includes a gas chromatograph inlet valve, a gas chromatograph station, an analysis pipeline, and a controller. The analysis pipeline is connected to the regenerative heat unit. A gas chromatograph inlet valve and a gas chromatograph station are arranged on the analysis pipeline. The gas chromatograph inlet valve and the gas chromatograph station are in telecommunication or communication connection with the controller.

[0012] As a preferred technical solution, the purification unit further includes a liquid nitrogen input pipeline, a liquid nitrogen output pipeline, a second helium output pipeline, and a first helium output pipeline connected to four adsorbers. Valves are arranged on the liquid nitrogen input pipeline, the liquid nitrogen output pipeline, the second helium output pipeline, and the first helium output pipeline.

[0013] As a preferred technical solution, the purification unit further includes a first backfill pipeline and a second backfill pipeline. The raw material gas input pipeline is communicated with the second helium output pipeline through the first backfill pipeline. A first group of backfill valves is arranged on the first backfill pipeline. The raw material gas input pipeline is communicated with the first helium output pipeline through the second backfill pipeline. A second group of backfill valves is arranged on the second backfill pipeline.

[0014] As a preferred technical solution, the purification unit further includes a high-purity nitrogen purge pipeline and a nitrogen discharge pipeline. The high-purity nitrogen purge pipeline is connected to the input end of the adsorber, and the nitrogen discharge pipeline is connected to the output end of the adsorber.

[0015] The present invention also provides a pressure building method for a pressure building device based on the above-mentioned low-temperature purification of helium, including pressurizing an adsorber under regeneration pressure using the product gas of a liquid air separator through the pressure building device in a medium-high pressure working state.

[0016] The beneficial effects of the present invention are as follows:

[0017] (1) In the present invention, through the setting of the pressure building device, it is possible to pressurize the adsorber under regeneration pressure using the product gas of the liquid air separator in a medium-high pressure working state, avoiding the pressurization of the adsorber under regeneration pressure by the adsorber in the working state and losing the pressure of the adsorber in the working state; due to the large pressure difference between the liquid air separator and the adsorber under regeneration pressure, medium-high pressure impact is likely to cause equipment damage. At the same time, the pressure building process is incorporated into the purification process to reduce the time required for pressure building. After the adsorber in the working state is saturated, the pressure building of the adsorber in the regeneration state is completed, and automatic switching can be realized to continuously produce high-purity helium gas, ensuring the satisfaction of the use requirements of high-purity gases.

[0018] (2) In the present invention, heat exchange is carried out between the output of the product gas helium and the input of the raw material gas through a heat exchanger, that is, the process of placing the heat exchange unit in front, making full use of the cold energy of the product gas and reducing the energy consumption in the purification process.

[0019] (3) In the present invention, two sets of purification units are arranged in parallel, and the product gas of one set is used to backfill and displace the other set to ensure the purity of the displacement gas, and the processes of three vacuum extractions and three backfill displacements are carried out to ensure the full and complete displacement of the purification unit.

[0020] (4) In the present invention, through the setting of the liquid air separation cylinder of the flash evaporation unit, components with higher boiling points in the components can be removed in advance, improving the purification efficiency and saving costs; and at the same time, the pressure building device is used to build pressure for the subsequent purification unit in advance to ensure the continuity of the purification process, which has strong applicability to the working conditions with large gas volume and high automation.

[0021] (5) In the present invention, through the setting of the purification unit, the problems of deep de-neon and de-hydrogenation in helium are solved, the problem of the source of the backfill gas in the activation regeneration process is solved, the stability and reliability of the backfill gas are ensured, the thoroughness of the device regeneration is ensured, and thus ultra-high purity helium with a purity of ≥99.9999% is obtained. Description of the Drawings

[0022] Figure 1 is the overall structural schematic diagram provided by the embodiment of the present invention;

[0023] Figure 2 is the structural schematic diagram of the purification unit provided by the embodiment of the present invention;

[0024] Figure 3Schematic structural diagram of the pressure building device provided by the embodiment of the present invention;

[0025] Figure 4 Schematic flow chart provided by the embodiment of the present invention;

[0026] Reference numerals in the attached drawings: 1. Inlet valve of the heat exchange unit; 2. Heat exchanger; 3. Raw gas pressure gauge; 4. Inlet valve of the flash evaporation unit; 5. Pressure gauge of the liquid air separator; 6. Liquid air separation cylinder; 7. Inlet valve of the purification unit; 8. Evacuation valve of purifier A; 9. Evacuation valve of purifier B; 10. Liquid nitrogen valve of purifier A; 11. Liquid nitrogen valve of purifier B; 12. Purifier A; 13. Purifier B; 14. Outlet valve of purifier A; 15. Outlet valve of purifier B; 16. Inlet valve of the regenerative unit; 17. Regenerative unit; 18. Outlet valve of the regenerative unit; 19. Inlet valve of the tube bundle; 20. Inlet valve of the gas chromatograph; 21. Gas chromatography station; 22. Tube bundle; 23. Vacuum pump A; 24. Pressure relief valve; 25. Pressure gauge of purifier A; 26. Pressure gauge of purifier B; 27. Air bag;

[0027] 28. Inlet valve of group I; 29. Inlet valve of group II; 30. Nitrogen inlet valve; 31. Nitrogen purge valve of group I; 32. Nitrogen purge valve of group II; 33. Evacuation valve of IA; 34. Evacuation valve of IIA; 35. Evacuation valve of IB; 36. Evacuation valve of IIB; 37. Inlet valve of vacuum pump A; 38. Inlet valve of vacuum pump B; 39. Liquid nitrogen inlet valve of IA; 40. Liquid nitrogen inlet valve of IIA; 41. Liquid nitrogen inlet valve of IB; 42. Liquid nitrogen inlet valve of IIB; 43. Liquid nitrogen discharge valve of IA; 44. Liquid nitrogen discharge valve of IIA; 45. Liquid nitrogen discharge valve of IB; 46. Liquid nitrogen discharge valve of IIB; 47. Pressure relief valve of group I; 48. Pressure relief valve of group II; 49. Nitrogen outlet valve of IA; 50. Nitrogen outlet valve of IIA; 51. Nitrogen outlet valve of IB; 52. Nitrogen outlet valve of IIB; 53. Backfill valve of group I; 54. Backfill valve of group II; 55. Vacuum pump A; 56. Vacuum pump B;

[0028] 57. Valve 1; 58. Valve 2; 59. Valve 3; 60. Orifice plate; 61. Valve 4; 62. Valve 5; 63. IA helium adsorber; 64. IIA helium adsorber; 65. IB helium adsorber; 66. IIB helium adsorber; 67. Feed gas input pipeline; 68. Liquid air separator inlet pipeline; 69. Purification main pipe; 70. Purification branch pipe 1; 71. Purification branch pipe 2; 72. Regeneration pipeline; 73. Analysis pipeline; 74. Liquid nitrogen pipeline; 75. Pressure build-up pipeline 1; 76. Pressure build-up pipeline 2; 77. Helium output pipeline 1; 78. Helium output pipeline 2; 79. Liquid nitrogen output pipeline; 80. Helium output valve 1; 81. Helium output valve 2; 82. Backfill pipeline 1; 83. Backfill pipeline 2; 84. Pressure relief pipeline; 85. High-purity nitrogen purge pipeline; 86. Nitrogen discharge pipeline; 87. Evacuation pipeline; 88. Nitrogen heater. Detailed implementation manners

[0029] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Apparently, the described embodiments are only a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] Refer to Figure 1 , Figure 2 , a purification system for helium containing nitrogen and neon impurities, comprising a heat exchange unit, a flash evaporation unit, a purification unit, and a regeneration unit connected in sequence, and an analysis unit and a filling unit are connected downstream of the regeneration unit;

[0031] The heat exchange unit includes a heat exchange unit intake valve 1, a heat exchanger 2, and a feed gas pressure gauge 3. The heat exchange unit intake valve 1, the feed gas pressure gauge 3, and the heat exchanger 2 are sequentially provided on the feed gas input pipeline 67. The function of the heat exchanger 2 is to exchange heat between the low-temperature helium gas of the product gas and the feed gas in the feed gas input pipeline to achieve cold utilization;

[0032] The flash evaporation unit includes a flash evaporation unit intake valve 4, a liquid air separator pressure gauge 5, and a liquid air separator inlet pipeline 68. The liquid air separator inlet pipeline is connected to the feed gas input pipeline, and the flash evaporation unit intake valve 4 and the liquid air separator pressure gauge 5 are sequentially provided on the liquid air separator inlet pipeline; the cooled feed gas enters the liquid air separation cylinder 6, and impurity gas flash evaporation separation is carried out in the liquid nitrogen temperature zone, and impurities higher than the boiling point of liquid nitrogen in the feed gas are removed under medium and high pressure. The separated feed gas enters the purification unit;

[0033] The purification unit includes a purification unit inlet valve 7, a purifier A evacuation valve 8, a purifier B evacuation valve 9, a purifier A 12, a purifier B 13, a purifier A outlet valve 14, a purifier B outlet valve 15, a vacuum pump 23, a purifier A pressure gauge 25, and a purifier B pressure gauge 26;

[0034] The purification pipeline includes a main purification pipeline 69, a first purification branch pipeline 70, and a second purification branch pipeline 71. The main purification pipeline is provided with a purification unit inlet valve 7. The main purification pipeline is connected to the purifier A 12 and the purifier B 13 respectively through two first purification branch pipelines 70. The purifier A 12 and the purifier B 13 are respectively heat-exchanged with the heat exchange unit through the second purification branch pipelines 71. After being heat-exchanged by the heat exchange unit, they are connected to the regenerative unit through a regenerative pipeline 72. The two second purification branch pipelines are respectively provided with a purifier A outlet valve 14 and a purifier B outlet valve 15. The purifier A 12 and the purifier B 13 are respectively connected to the vacuum pump 23 through an evacuation pipeline. The two evacuation pipelines are respectively provided with a purifier A evacuation valve 8 and a purifier B evacuation valve 9. The purifier A 12 and the purifier B 13 are respectively connected with a purifier A pressure gauge 25 and a purifier B pressure gauge 26;

[0035] The regenerative unit includes a regenerative unit inlet valve 16, a regenerative unit 17, a regenerative unit outlet valve 18, and a regenerative pipeline 72. The regenerative pipeline is successively provided with a regenerative unit inlet valve 16, a regenerative unit 17, and a regenerative unit outlet valve 18. A pressure relief pipeline 84 is also connected to the regenerative pipeline at the upstream of the regenerative unit outlet valve 18. The downstream of the pressure relief pipeline is connected to an airbag 27. A pressure relief valve 24 is provided on the pressure relief pipeline 84. In fact, two pressure relief valves 24 are set here, namely a group I pressure relief valve 47 and a group II pressure relief valve 48;

[0036] The analysis unit includes a gas chromatograph inlet valve 20, a gas chromatography station 21, an analysis pipeline 73, and a controller. One end of the analysis pipeline 73 is connected to the regenerative pipeline of the regenerative unit. A gas chromatograph inlet valve 20 is provided thereon. The controller is electrically or communicatively connected to the gas chromatograph inlet valve 20 and the gas chromatography station 21;

[0037] The liquid nitrogen filling and discharging unit includes a purifier A liquid nitrogen valve 10, a purifier B liquid nitrogen valve 11, and external liquid nitrogen. The external liquid nitrogen is connected to the purifier A 12 and the purifier B 13 through a liquid nitrogen input pipeline 74. The two liquid nitrogen input pipelines 74 are respectively provided with a purifier A liquid nitrogen valve 10 and a purifier B liquid nitrogen valve 11; the purifier A liquid nitrogen valve 10 corresponds to an IA liquid nitrogen inlet valve 39 and an IIA liquid nitrogen inlet valve 40; the purifier B liquid nitrogen valve 11 corresponds to an IB liquid nitrogen inlet valve 41 and an IIB liquid nitrogen inlet valve 42;

[0038] The filling unit includes a bundle inlet valve 19 and a bundle 22. The bundle 22 is connected to the regenerative pipeline. A bundle inlet valve 19 is provided on the bundle 22;

[0039] in, Figure 1 Purifier A12 in Figure 2 IA helium adsorber 63, IIA helium adsorber 64, Figure 1 Purifier B13 in Figure 2 IB helium adsorber 65, IIB helium adsorber 66;

[0040] It should be noted that two groups of adsorbers are used, each group of adsorbers has two, and adsorption and regeneration are performed in turn to ensure the continuity of the adsorption purification process. In this embodiment, one group of flash units is provided, and two groups of purification units are provided. The flash unit is a common part of the two purification units. The process gas first passes through the flash unit and then switches to the purification unit. The purpose of setting two groups of purification units is that when one group is working, the other group is regenerating and activating. The activation time can be reduced by the pressure building device, ensuring the smooth and reliable operation of the device, and can stably produce high-purity gas with a purity of 99.9999% or above;

[0041] The pressure building device includes a pressure building pipeline 1, a pressure building pipeline 2, and a valve 3 59, an orifice plate 60, a valve 4 61, and a valve 5 62 arranged on the pressure building pipeline 2 in sequence. A valve 1 57 and a valve 2 58 are arranged on the pressure building pipeline 1. The valve 1 57 is used to control the flow rate of process gas. Different opening degrees result in different flow rates. It is a normally open valve. The valve 2 58 is used to control the cut-off and opening and closing of process gas.

[0042] Valve three 59 is an on-off valve to control the process gas switch. The orifice plate 60 functions as a throttling valve to mechanically control the process gas flow rate. It can only control a certain flow rate according to the size of the orifice plate 60 and the corresponding pressure, and cannot be precisely controlled. Valve four 61 functions to precisely control the process gas flow rate. Different openings result in different flow rates. Valve five 62 functions as an on-off valve to control the process gas switch. It can ensure the safe and stable operation of the equipment, and realize continuous and stable gas discharge from the equipment. The pressure building process is carried out in the purification process to reduce the time required for pressure building.

[0043] After the raw gas is purified by low-temperature adsorption in the purification unit, it first enters the heat exchange unit to exchange heat with the raw gas, and then enters the heat recovery unit. After the temperature is recovered, according to the helium purity detection result in the product gas, the impure helium enters the low-purity helium storage tank or the air bag 27, the pure helium enters the helium storage and loading facility, and the pure helium enters the helium filling device. This improvement adopts the setting of interlocking the analysis room and the outlet valve. The analysis room refers to the gas chromatography station 21. The interlocking means that the gas chromatography station 21 detects that the purity of the helium is qualified and opens the tube bundle inlet valve 19. If it is unqualified, the tube bundle inlet valve 19 is not opened, so as to ensure the continuity of the high-purity helium supply, recover the impure helium, and improve the recovery rate of the helium.

[0044] After the purifier A12 finishes its operation, it enters the regeneration mode, and the purifier B13 enters the working state. At this time, the IA helium adsorber 63 and the IIA helium adsorber 64 need to go through processes such as pressure relief, liquid nitrogen drainage, heating, nitrogen purging, vacuum pumping, and pure helium backfilling. After regeneration, liquid nitrogen is filled and the pressure is built up. When the adsorption cylinder of the purification unit is too large, the gas consumption for pressure build-up is very large and the pressure build-up time is very long. In the existing switching process, after the adsorbers are switched, the pressure needs to be built up to the working pressure first. At this time, the equipment is in a state of not discharging gas and is in the pressure build-up state. At the same time, in the working state at high pressure (20 MPa), the IB helium adsorber 65 and the IIB helium adsorber 66 in the working state cannot pressurize the IA helium adsorber 63 and the IIA helium adsorber 64 in the adsorption cylinder during regeneration. The gas demand is large, and directly building the pressure will cause too large a pressure drop in the adsorbers in the working state, making the equipment unable to operate stably and having a great impact on the purity of the product helium. At the same time, the pressure difference between the adsorbers in the working state and the adsorbers that need to build pressure is relatively large, and the high-pressure impact is likely to cause equipment damage. At this time, the product gas (with pressure) of the liquid air separation cylinder 6 of the flash evaporation unit is used to pre-pressurize the IB helium adsorber 65 and the IIB helium adsorber 66, saving the pressure build-up time, enabling the equipment to operate continuously, stably produce gas, and improve the product purity.

[0045] Refer to Figure 2 、 Figure 3 The pressure build-up device is connected to the flash evaporation unit and the purification unit, and two sets are set up, which are respectively connected to the IA helium adsorber 63 and the IIA helium adsorber 64, hereinafter referred to as Group A, and the IB helium adsorber 65 and the IIB helium adsorber 66, hereinafter referred to as Group B;

[0046] Refer to Figure 2, High-purity helium gas is output from the IA helium adsorber 63 and the IIA helium adsorber 64 through the helium output pipeline 77. High-purity helium gas is output from the IB helium adsorber 65 and the IIB helium adsorber 66 through the helium output pipeline 78. A helium output valve 80 and a helium output valve 81 are respectively provided on the helium output pipeline 77 and the helium output pipeline 78. The liquid nitrogen input pipeline 74 is respectively connected to the IA helium adsorber 63, the IIA helium adsorber 64, the IB helium adsorber 65, and the IIB helium adsorber 66. Valves are provided on the four liquid nitrogen input pipelines 74, which are respectively the IA liquid nitrogen inlet valve 39, the IIA liquid nitrogen inlet valve 40, the IB liquid nitrogen inlet valve 41, and the IIB liquid nitrogen inlet valve 42. The four liquid nitrogen output pipelines 79 are respectively connected to the IA helium adsorber 63, the IIA helium adsorber 64, the IB helium adsorber 65, and the IIB helium adsorber 66. An IA liquid nitrogen discharge valve 43, an IIA liquid nitrogen discharge valve 44, an IB liquid nitrogen discharge valve 45, and an IIB liquid nitrogen discharge valve 46 are respectively provided thereon; the raw material gas input pipeline 67 is respectively connected in series with the IA helium adsorber 63 through the IA helium adsorber 64 and connected to the IB helium adsorber 66 through the IB helium adsorber 65. A group I intake valve 28 and a group II intake valve 29 are respectively provided thereon;

[0047] The raw gas input pipeline 67 is connected to the helium output pipeline two 78 through the liquid air separator inlet pipeline 68 and the purification main pipe 69 through the backfill pipeline one 82. A group of backfill valves 53 are provided on the backfill pipeline one 82. The raw gas input pipeline 67 is connected to the helium output pipeline one 77 through the backfill pipeline two 83. A group of backfill valves 54 are provided on the backfill pipeline two 83. Pressure relief pipelines 84 are connected to both the helium output pipeline one 77 and the helium output pipeline two 78. An I group of pressure relief valves 47 and an II group of pressure relief valves 48 are respectively provided on the two pressure relief pipelines 84. Two high-purity nitrogen purge pipelines 85 are also connected to the raw gas input pipeline 67, corresponding to group A and group B respectively. An I group of nitrogen purge valves 31 and an II group of nitrogen purge valves 32 are respectively provided on the two high-purity nitrogen pipelines 85. Nitrogen discharge pipelines 86 are also connected to the IA helium adsorber 63, the IIA helium adsorber 64, the IB helium adsorber 65, and the IIB helium adsorber 66. An IA nitrogen outlet valve 49, an IIA nitrogen outlet valve 50, an IB nitrogen outlet valve 51, and an IIB nitrogen outlet valve 52 are respectively provided on the four nitrogen discharge pipelines 86. The IA helium adsorber 63, the IIA helium adsorber 64, the IB helium adsorber 65, and the IIB helium adsorber 66 are all connected to evacuation pipelines 87. An IA evacuation valve 33, an IIA evacuation valve 34, an IB evacuation valve 35, and an IIB evacuation valve 36 are respectively provided on the evacuation pipelines 87. Two vacuum pumps are provided on the evacuation pipeline, namely vacuum pump A 55 and vacuum pump B 56, one in use and one in reserve. And vacuum pump inlet valves A 37 and vacuum pump inlet valves B 38 are respectively provided at the input ends of the vacuum pump A 55 and the vacuum pump B 56. A nitrogen heater 88 is provided on the high-purity nitrogen purge pipeline 85.

[0048] It should be noted that Figure 2 the helium output pipeline one 77 and the helium output pipeline two 78 in Figure 1 correspond to the purification branch pipe two 71 in

[0049] Working principle:

[0050] Activation steps for group A / B:

[0051] Step 1. Pressure relief: Close the heat exchange unit inlet valve 1, open the flash evaporation unit inlet valve 4, open the purification unit inlet valve 7, open the purifier A outlet valve 14 or the purifier B outlet valve 15, the regenerative heat exchange unit inlet valve 16, and the pressure relief valve 24. Release the pressure gas to the recovery airbag 27. After the pressure relief of the purifier is completed, close the purification unit inlet valve 7, and open the purifier A outlet valve 14, the purifier B outlet valve 15, the regenerative heat exchange unit inlet valve 16, and the pressure relief valve 24;

[0052] Step 2. Drain liquid nitrogen: Open the IA liquid nitrogen discharge valve 43 and the IIA liquid nitrogen discharge valve 44 to empty the liquid nitrogen outlet pipeline; or open the IB liquid nitrogen discharge valve 45 and the IIB liquid nitrogen discharge valve 46 to empty the liquid nitrogen outlet pipeline.

[0053] 1. Heating: The purifiers IA and IIA, namely the IA helium adsorbers 63 and the IIA helium adsorbers 64, are turned on for heating; or the purifiers IB and IIB, namely the IB helium adsorbers 65 and the IIB helium adsorbers 66, are turned on for heating.

[0054] 2. Nitrogen purging: Check that the external nitrogen supply is normal, turn on the nitrogen heater 88, open the Group I nitrogen purging valve 31, the Group II nitrogen purging valve 32, the IA nitrogen outlet valve 49, and the IB nitrogen outlet valve 51; purge for 4 hours to complete the nitrogen purging process, and then close the nitrogen purging valves, namely the Group I nitrogen purging valve 31, the Group II nitrogen purging valve 32, the IA nitrogen outlet valve 49, and the IB nitrogen outlet valve 51. The same applies to Group B.

[0055] Step 3. First vacuum pumping: Open the IA evacuation valve 33 and the IIA evacuation valve 34, turn on the vacuum pump A 55 and the vacuum pump B 56, continuously pump for 3 hours. When the reading of the vacuum gauge is qualified, the first vacuum pumping process is completed. Then close the IA purifier evacuation valve 33 and the IIA evacuation valve 34, and turn off the vacuum pump A 55 and the vacuum pump B 56. The same applies to Group B.

[0056] Step 4. First backfilling: If backfilling is required for Group A, open the product gas path purifier B outlet valve 15 of Group B. When the backfilling pressure reaches 3 - 5 bar, the first backfilling is completed.

[0057] Step 5. Pressure relief: Open the Group I pressure relief valve 47, the Group II pressure relief valve 48, and the pressure relief valve 24 to relieve the pressure gas to the airbag 27. When the pressure relief is completed, close the Group I pressure relief valve 47, the Group II pressure relief valve 48, and the pressure relief valve 24.

[0058] Step 6. The above vacuum pumping, pressure relief, and backfilling steps are carried out three times in sequence.

[0059] The activation is completed. Check that all valves of Group A / Group B are closed.

[0060] Purification steps for Group A / B:

[0061] Step 1. Confirm that the IA liquid nitrogen inlet valve 39 or the IB liquid nitrogen inlet valve 41 and the IIA liquid nitrogen inlet valve 40 or the IIB liquid nitrogen inlet valve 42 of the purifier A12 or the purifier B13 are open. When the liquid level is filled to the predetermined height, close the IA liquid nitrogen inlet valve 39 or the IB liquid nitrogen inlet valve 41 and the IIA liquid nitrogen inlet valve 40 or the IIB liquid nitrogen inlet valve 42 of the purifier A12. When the liquid level is lower than the predetermined height, open the IA liquid nitrogen inlet valve 39 and the IIA liquid nitrogen inlet valve 40.

[0062] Step 2: Open the Group I intake valve 28, the flash unit intake valve 4, the purification unit intake valve 7, the purifier A outlet valve 14 or the purifier B outlet valve 15, and the regenerative unit intake valve 16.

[0063] Step 3: Gradually open the regenerative unit outlet valve 18 to the operating pressure of the equipment. When the gas purity detected by the chromatograph station 21 of the outlet gas is unqualified, open the pressure relief valve 24 to the airbag 27. When the gas purity detected by the chromatograph is qualified, open the regenerative unit outlet valve 18 and the tube bundle valve 19, and the product gas goes to the tube bundle 22;

[0064] Before the purification of Group A / Group B is completed, the already regenerated Group B / Group A is used in advance. Figure 3 The pressure building device builds pressure. After completion, switch to the purification of Group B / Group A and run alternately repeatedly to ensure the continuous and stable operation of the equipment.

[0065] 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 foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A helium low-temperature purification pressure-building device, characterized in that It includes a flash evaporation unit, a purification unit, and a heat regeneration unit connected in sequence. The flash evaporation unit is connected to the purification unit through a pressure building device. The pressure building device includes a parallel pressure building pipeline 1 and a pressure building pipeline 2. A control valve is provided on the pressure building pipeline 1, and an orifice plate is provided on the pressure building pipeline 2. Control valves are provided upstream and downstream of the orifice plate. The purification unit includes two groups of adsorbers. Each group of adsorbers includes two serially connected adsorbers. The two groups of adsorbers are respectively connected to the raw material gas input pipeline connected to the flash evaporation unit through the pressure building device.

2. The helium gas low-temperature purification pressure building device according to claim 1, wherein It further includes a heat exchange unit. The heat exchange unit is provided upstream of the flash evaporation unit. A heat exchange unit inlet valve, a heat exchanger, and a raw material gas pressure gauge are sequentially provided on the raw material gas input pipeline. Helium output pipelines are connected to both groups of adsorbers. The helium output pipeline exchanges heat with the raw material gas input pipeline through the heat exchanger. The gas in the helium output pipeline is input into the heat regeneration unit after heat exchange.

3. The helium low-temperature purification pressure building device according to claim 1, characterized in that, The flash evaporation unit includes a liquid air separator inlet pipeline and a flash evaporation unit inlet valve, a liquid air separator pressure gauge, and a liquid air separation cylinder sequentially provided on the liquid air separator inlet pipeline. The liquid air separation cylinder can flash-separate the impurity gas in the raw material gas and cause the separated raw material gas to enter the purification unit.

4. The helium low-temperature purification pressure building device according to claim 1, characterized in that, The heat regeneration unit includes a heat regeneration pipeline and a heat regeneration unit inlet valve, a heat regeneration unit, and a heat regeneration unit outlet valve provided on the heat regeneration pipeline.

5. The helium low-temperature purification pressure building device according to claim 4, characterized in that, A pressure relief pipeline is further connected to the heat regeneration pipeline upstream of the heat regeneration unit outlet valve. An airbag is connected to the downstream of the pressure relief pipeline. A pressure relief valve is provided on the pressure relief pipeline.

6. The helium gas low-temperature purification pressure building device according to claim 1, characterized in that, An analysis unit is further connected to the downstream of the heat regeneration unit. The analysis unit includes a gas chromatograph inlet valve, a gas chromatograph station, an analysis pipeline, and a controller. The analysis pipeline is connected to the heat regeneration unit. A gas chromatograph inlet valve and a gas chromatograph station are provided on the analysis pipeline. The gas chromatograph inlet valve and the gas chromatograph station are electrically or communicatively connected to the controller.

7. The helium low-temperature purification pressure building device according to claim 1, characterized in that, The purification unit further includes a liquid nitrogen input pipeline, a liquid nitrogen output pipeline, a helium output pipeline 2, and a helium output pipeline 1 connected to the four adsorbers. Valves are provided on the liquid nitrogen input pipeline, the liquid nitrogen output pipeline, the helium output pipeline 1, and the helium output pipeline 2.

8. The helium gas low-temperature purification pressure building device according to claim 7, characterized in that, The purification unit further includes a backfill pipeline 1 and a backfill pipeline 2. The raw material gas input pipeline is communicated with the helium output pipeline 2 through the backfill pipeline 1. A group I backfill valve is provided on the backfill pipeline 1. The raw material gas input pipeline is communicated with the helium output pipeline 1 through the backfill pipeline 2. A group II backfill valve is provided on the backfill pipeline 2.

9. The helium low-temperature purification pressure building device according to claim 1, characterized in that, The purification unit further includes a high-purity nitrogen purging pipeline and a nitrogen discharging pipeline. The high-purity nitrogen purging pipeline is connected to the input end of the adsorber. The nitrogen discharging pipeline is connected to the output end of the adsorber.

10. A pressure building method for a pressure building device using helium cryogenic purification as described in any one of claims 1-9, characterized in that, It includes that in the high-pressure working state, the product gas is used through the pressure building device to build pressure on the adsorber under regeneration and pressure building.

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