A continuous operating parallel type helium-3 distillation system

Abstract

This invention relates to the field of gas separation technology, and more particularly to a continuously operating parallel helium-3 distillation system. The continuously operating parallel helium-3 distillation system includes a refrigeration unit, a raw gas inlet pipe connected to the inlet of the refrigeration unit, and further includes a first helium-3 distillation circuit system and a second helium-3 distillation circuit system connected in parallel to the outlet of the refrigeration unit, a first gas cylinder for recovering low helium-3 abundance, and a second gas cylinder for recovering high helium-3 abundance. This invention can achieve efficient and wide-abundance enrichment of helium-3 in a single-stage distillation system, and by employing a parallel distillation circuit system, long-term continuous operation of the helium-3 distillation process can be achieved through switching of the distillation circuit systems.

Description

Technical Field

[0001] This utility model relates to the field of gas separation technology, and in particular to a continuously operating parallel helium-3 distillation system. Background Technology

[0002] The main technical routes for helium-3 enrichment include: cryogenic distillation / deep cryogenic distillation (approximately 0.7–4 K), superfluid "superleak" membrane separation, low-temperature adsorption / chromatography (TSA / PSA pre-concentration of activated carbon and zeolite), physical separation such as gas centrifugation and thermal diffusion, cutting-edge schemes such as low-temperature membrane quantum sieving and laser isotope separation, and separation chains combined with tritium aging and recovery. Among these, cryogenic distillation utilizes the slight differences in vapor pressure and boiling point between helium-3 and helium-4 at low temperatures to achieve relative volatility separation, and is the most mature and easily scaled up for engineering.

[0003] Currently, most methods for separating helium-3 by distillation employ a single distillation system or unit, which can only perform a single separation operation on a specific volume of gas. After the entire distillation process is completed, the condensation and liquefaction processes need to be restarted. Furthermore, the superfluid helium climbing membrane suppression effect is poor, and the temperature distribution control is inadequate, resulting in poor distillation efficiency and low helium-3 abundance values ​​obtained from a single distillation.

[0004] Therefore, existing technologies still need to be improved and developed. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a continuously operating parallel helium-3 distillation system, which aims to solve the problem that the entire distillation process cannot be operated continuously for a long period of time through the parallel scheme.

[0006] This utility model is achieved through the following technical solution:

[0007] A continuously operating parallel helium-3 distillation system includes a refrigeration device, a raw gas inlet pipe connected to the inlet of the refrigeration device, a first helium-3 distillation circuit system and a second helium-3 distillation circuit system connected in parallel to the outlet of the refrigeration device, a first gas cylinder for recovering low helium-3 abundance, and a second gas cylinder for recovering high helium-3 abundance.

[0008] A first inlet pipe and valve assembly are provided between the inlet of the first helium-3 distillation circuit system and the outlet of the refrigeration device, and a second inlet pipe and valve assembly are provided between the inlet of the second helium-3 distillation circuit system and the outlet of the refrigeration device.

[0009] The first helium-3 distillation circuit system has a first high-abundance recovery pipe and valve assembly, and a first low-abundance recovery pipe and valve assembly at its outlet. The second helium-3 distillation circuit system has a second high-abundance recovery pipe and valve assembly, and a second low-abundance recovery pipe and valve assembly at its outlet.

[0010] The first high-abundance recovery pipe and valve assembly and the second high-abundance recovery pipe and valve assembly are respectively connected to the second gas cylinder, and the first low-abundance recovery pipe and valve assembly and the second low-abundance recovery pipe and valve assembly are respectively connected to the first gas cylinder.

[0011] Optionally, the first helium-3 distillation circuit system further includes a first countercurrent heat exchanger, a first liquid helium evaporation chamber, a first extraction pipe, a first circulating pump group, a first high-abundance recovery pipe and valve assembly, and a first low-abundance recovery pipe and valve assembly;

[0012] The second helium-3 distillation circuit system also includes a second countercurrent heat exchanger, a second liquid helium evaporation chamber, a second extraction pipe, a second circulating pump set, a second high-abundance recovery pipe and valve assembly, and a second low-abundance recovery pipe and valve assembly;

[0013] The first countercurrent heat exchanger includes a first inlet pipe and a first outlet pipe. One end of the first inlet pipe is connected to the outlet of the refrigeration device through a first inlet pipe and a valve assembly, and the other end of the first inlet pipe is connected to the first liquid helium evaporation chamber. One end of the first outlet pipe is connected to the first liquid helium evaporation chamber, and the other end of the first outlet pipe is connected to one end of the first extraction pipe. The other end of the first extraction pipe is connected to a first circulation pump group. The first circulation pump group is connected to a first gas cylinder and a second gas cylinder through a first high abundance recovery pipe and a valve assembly and a first low abundance recovery pipe and a valve assembly, respectively.

[0014] The second countercurrent heat exchanger includes a second inlet pipe and a second outlet pipe. One end of the second inlet pipe is connected to the outlet of the refrigeration device through a second inlet pipe and a valve assembly, and the other end of the second inlet pipe is connected to the second liquid helium evaporation chamber. One end of the second outlet pipe is connected to the second liquid helium evaporation chamber, and the other end of the second outlet pipe is connected to one end of the second extraction pipe. The other end of the second extraction pipe is connected to a second circulation pump group. The second circulation pump group is connected to the first gas cylinder and the second gas cylinder through a second high abundance recovery pipe and a valve assembly and a second low abundance recovery pipe and a valve assembly, respectively.

[0015] Optionally, the refrigeration device includes a refrigeration unit, a primary heat exchanger, a secondary heat exchanger, and a tertiary heat exchanger that are thermally connected to the refrigeration unit. The primary heat exchanger, the secondary heat exchanger, and the tertiary heat exchanger are connected in sequence. The first inlet pipe and valve assembly and the second inlet pipe and valve assembly are connected in parallel at the outlet of the tertiary heat exchanger.

[0016] Optionally, the continuously operating parallel helium-3 distillation system further includes a vacuum enclosure, a primary cold shield, a secondary cold shield, and a tertiary cold shield, wherein the tertiary cold shield...

[0017] The three-stage cold shield is installed outside the first countercurrent heat exchanger, the first liquid helium evaporation chamber, the second countercurrent heat exchanger, and the second liquid helium evaporation chamber.

[0018] The secondary cold shield is installed outside the tertiary heat exchanger.

[0019] The primary cold shield is installed outside the secondary heat exchanger.

[0020] The vacuum enclosure is placed outside the first-stage heat exchanger.

[0021] Optionally, the continuously operating parallel helium-3 distillation system further includes a precooling system, which includes a primary heat exchanger, a secondary heat exchanger, a precooling liquid pool, a third extraction pipe, a third circulating pump set, an inlet valve, a precooling gas cylinder, and an outlet valve.

[0022] The second primary heat exchanger is located inside the vacuum enclosure and outside the first primary cold shield; the second secondary heat exchanger is located inside the first primary cold shield and outside the second secondary cold shield; and the precooling liquid pool is located inside the second secondary cold shield and outside the third primary cold shield.

[0023] The precooling gas cylinder is connected to the first-stage heat exchanger 2 via an inlet valve. The first-stage heat exchanger 2, the second-stage heat exchanger 2, and the precooling liquid pool are connected in sequence. One end of the third exhaust pipe is connected to the outlet of the precooling liquid pool, and the other end is connected to the third circulation pump group. The other end of the third circulation pump group is connected to the precooling gas cylinder via an outlet valve.

[0024] Beneficial effects: This invention can achieve efficient and wide-abundance enrichment of helium-3 in a single-stage distillation system. At the same time, it adopts a parallel distillation circuit system, and the long-term continuous operation of the helium-3 distillation process can be achieved by switching the distillation circuit system. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of Example 1.

[0026] Figure 2 This is a schematic diagram of the structure of Example 2.

[0027] Figure 3 This is a schematic diagram of the structure of Example 3.

[0028] Figure 4 Example 4: Structural diagram. Detailed Implementation

[0029] This invention provides a continuously operating parallel helium-3 distillation system. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the following provides a more detailed description. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this invention.

[0030] In the description of this utility model, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, in the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] Example 1

[0032] like Figure 1 As shown, a continuously operating parallel helium-3 distillation system of this embodiment includes a refrigeration device 5, a raw gas inlet pipe 1 connected to the gas inlet of the refrigeration device 5, a first helium-3 distillation circuit system 2 and a second helium-3 distillation circuit system 3 connected in parallel to the gas outlet of the refrigeration device 5, a first gas cylinder 10-1 for recovering low helium-3 abundance, and a second gas cylinder 10-2 for recovering high helium-3 abundance.

[0033] A first inlet pipe and valve assembly 2-1 are provided between the inlet of the first helium-3 distillation circuit system 2 and the outlet of the refrigeration device 5; a second inlet pipe and valve assembly 3-1 are provided between the inlet of the second helium-3 distillation circuit system 3 and the outlet of the refrigeration device 5.

[0034] The first helium-3 distillation circuit system 2 has a first high-abundance recovery pipe and valve assembly 2-6 and a first low-abundance recovery pipe and valve assembly 2-7 in the outlet direction, and the second helium-3 distillation circuit system 3 has a second high-abundance recovery pipe and valve assembly 3-6 and a second low-abundance recovery pipe and valve assembly 3-7 in the outlet direction.

[0035] The first high-abundance recovery pipe and valve assembly 2-6 and the second high-abundance recovery pipe and valve assembly 3-6 are respectively connected to the second gas cylinder 10-2, and the first low-abundance recovery pipe and valve assembly 2-7 and the second low-abundance recovery pipe and valve assembly 3-7 are respectively connected to the first gas cylinder 10-1.

[0036] It should be noted that in the initial state: the first inlet pipe and valve assembly 2-1 are opened to start the distillation process of the first helium-3 distillation circuit system 2, and the first low abundance recovery pipe and valve assembly 2-7 are opened to recover the small amount of gas initially evaporated into the first gas cylinder 10-1.

[0037] High abundance recovery state: After the temperature drops below 0.8K and the abundance of He-3 vaporized gas in the pipeline reaches a high level, generally set to >80%, close the first low abundance recovery pipe and valve assembly 2-7, open the first high abundance recovery pipe and valve assembly 2-6, and recover the high abundance of He-3 vaporized gas into the second gas cylinder 10-2.

[0038] Residual low abundance recovery of the first helium-3 distillation circuit system 2: As the abundance of helium-3 in the first helium-3 distillation circuit system 2 continues to decrease, the temperature continues to rise until the temperature rises again to above 0.8K. After the abundance of helium-3 vaporized gas in the system gradually decreases to a low level, generally set to <70%, the first high abundance recovery pipe and valve assembly 2-6 are closed, and the first low abundance recovery pipe and valve assembly 2-7 are opened to recover the low abundance of helium-3 vaporized gas to the first recovery cylinder 10-1.

[0039] The second helium-3 distillation circuit system 3 begins liquefaction: while recovering the residual low abundance from the first helium-3 distillation circuit system 2, the first inlet pipe and valve assembly 2-1 are closed, the second inlet pipe and valve assembly 3-1 are opened, and then the above steps are repeated from the second helium-3 distillation circuit system 3.

[0040] Example 2

[0041] like Figure 2 As shown, the first helium-3 distillation circuit system 2 in this embodiment also includes a first countercurrent heat exchanger 2-2, a first liquid helium evaporation chamber 2-3, a first extraction pipe 2-4, a first circulating pump group 2-5, a first high abundance recovery pipe and valve assembly 2-6, and a first low abundance recovery pipe and valve assembly 2-7;

[0042] The second helium-3 distillation circuit system 3 also includes a second countercurrent heat exchanger 3-2, a second liquid helium evaporation chamber 3-3, a second extraction pipe 3-4, a second circulating pump group 3-5, a second high-abundance recovery pipe and valve assembly 3-6, and a second low-abundance recovery pipe and valve assembly 3-7;

[0043] The first countercurrent heat exchanger 2-2 includes a first inlet pipe 2-2-1 and a first outlet pipe 2-2-2. One end of the first inlet pipe 2-2-1 is connected to the outlet of the refrigeration device 5 through a first inlet pipe and valve assembly 2-1, and the other end of the first inlet pipe 2-2-1 is connected to the first liquid helium evaporation chamber 2-3. One end of the first outlet pipe 2-2-2 is connected to the first liquid helium evaporation chamber 2-3, and the other end of the first outlet pipe 2-2-2 is connected to one end of the first extraction pipe 2-4. The other end of the first extraction pipe 2-4 is connected to the first circulation pump group 2-5. The first circulation pump group 2-5 is connected to the first gas cylinder 10-1 and the second gas cylinder 10-2 through a first high abundance recovery pipe and valve assembly 2-6 and a first low abundance recovery pipe and valve assembly 2-7, respectively.

[0044] The second countercurrent heat exchanger 3-2 includes a second inlet pipe 3-2-1 and a second outlet pipe 3-2-2. One end of the second inlet pipe 3-2-1 is connected to the outlet of the refrigeration device 5 through a second inlet pipe and valve assembly 3-1, and the other end of the second inlet pipe 3-2-1 is connected to the second liquid helium evaporation chamber 3-3. One end of the second outlet pipe 3-2-2 is connected to the second liquid helium evaporation chamber 3-3, and the other end of the second outlet pipe 3-2-2 is connected to one end of the second extraction pipe 3-4. The other end of the second extraction pipe 3-4 is connected to the second circulation pump group 3-5. The second circulation pump group 3-5 is connected to the first gas cylinder 10-1 and the second gas cylinder 10-2 through a second high abundance recovery pipe and valve assembly 3-6 and a second low abundance recovery pipe and valve assembly 3-7, respectively.

[0045] It should be noted that when the first inlet pipe and valve assembly 2-1 are opened, the first helium-3 distillation circuit system 2 is used for distillation. When the second inlet pipe and valve assembly 3-1 are opened, the second helium-3 distillation circuit system 3 is used for distillation. The raw gas enters the first countercurrent heat exchanger 2-2 for cooling and liquefaction, and then enters the first liquid helium evaporation chamber 2-3 until the first liquid helium evaporation chamber 2-3 is almost completely filled with liquid. Then the first circulation pump group 2-5 is turned on to start the distillation process.

[0046] Example 3

[0047] like Figure 3 As shown, the refrigeration device in this embodiment includes a refrigeration unit 5-1, a primary heat exchanger 5-2, a secondary heat exchanger 5-3, and a tertiary heat exchanger 5-4 that are thermally connected to the refrigeration unit 5-1. The primary heat exchanger 5-2, the secondary heat exchanger 5-3, and the tertiary heat exchanger 5-4 are connected in sequence. The first inlet pipe and valve assembly 2-1 and the second inlet pipe and valve assembly 3-1 are connected in parallel at the outlet of the tertiary heat exchanger 5-4.

[0048] Optionally, the continuously operating parallel helium-3 distillation system further includes a vacuum enclosure 6, a primary cold shield 7, a secondary cold shield 8, and a tertiary cold shield 9, wherein the tertiary cold shield 9...

[0049] The three-stage cold shield 9 is installed outside the first counter-current heat exchanger 2-2, the first liquid helium evaporation chamber 2-3, the second counter-current heat exchanger 3-2, and the second liquid helium evaporation chamber 3-3.

[0050] The secondary cold shield 8 is installed outside the tertiary heat exchanger 5-4.

[0051] The primary cold shield 7 is installed outside the secondary heat exchanger 5-3.

[0052] The vacuum casing 6 is installed outside the primary heat exchanger 5-2.

[0053] Example 4

[0054] like Figure 4 As shown, the continuously operating parallel helium-3 distillation system described in this embodiment also includes a precooling system 4, which includes a first-stage heat exchanger 4-1, a second-stage heat exchanger 4-2, a precooling liquid pool 4-3, a third extraction pipe 4-4, a third circulation pump group 4-5, an inlet valve 4-6, a precooling gas cylinder 4-7, and an outlet valve 4-8.

[0055] The first-stage heat exchanger 4-1 is located inside the vacuum casing 6 and outside the first-stage cold shield 7; the second-stage heat exchanger 4-2 is located inside the first-stage cold shield 7 and outside the second-stage cold shield 8; and the precooling liquid pool 4-3 is located inside the second-stage cold shield 8 and outside the third-stage cold shield 9.

[0056] The precooling gas cylinder 4-7 is connected to the first-stage heat exchanger 4-1 via an inlet valve 4-6. The first-stage heat exchanger 4-1, the second-stage heat exchanger 4-2, and the precooling liquid pool 4-3 are connected in sequence. One end of the third exhaust pipe 4-4 is connected to the outlet of the precooling liquid pool 4-3, and the other end is connected to the third circulation pump group 4-5. The other end of the third circulation pump group 4-5 is connected to the precooling gas cylinder 4-7 via an outlet valve 4-8.

[0057] It should be noted that in this embodiment, the helium gas in the pre-cooling cylinders 4-7 can be pre-cooled to a certain temperature, which will not cause waste and can provide a pre-cooling temperature below 0.5K or below 1.2K.

[0058] It should be understood that the application of this utility model is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A continuously operating parallel helium-3 distillation system, comprising a refrigeration unit and a raw gas inlet pipe connected to the inlet of the refrigeration unit, characterized in that, The continuously operating parallel helium-3 distillation system also includes a first helium-3 distillation circuit system and a second helium-3 distillation circuit system connected in parallel at the outlet of the refrigeration unit, a first gas cylinder for recovering low helium-3 abundance, and a second gas cylinder for recovering high helium-3 abundance. A first inlet pipe and valve assembly are provided between the inlet of the first helium-3 distillation circuit system and the outlet of the refrigeration device, and a second inlet pipe and valve assembly are provided between the inlet of the second helium-3 distillation circuit system and the outlet of the refrigeration device. The first helium-3 distillation circuit system has a first high-abundance recovery pipe and valve assembly, and a first low-abundance recovery pipe and valve assembly at its outlet. The second helium-3 distillation circuit system has a second high-abundance recovery pipe and valve assembly, and a second low-abundance recovery pipe and valve assembly at its outlet. The first high-abundance recovery pipe and valve assembly and the second high-abundance recovery pipe and valve assembly are respectively connected to the second gas cylinder, and the first low-abundance recovery pipe and valve assembly and the second low-abundance recovery pipe and valve assembly are respectively connected to the first gas cylinder.

2. The continuously operating parallel helium-3 distillation system according to claim 1, characterized in that, The first helium-3 distillation circuit system also includes a first countercurrent heat exchanger, a first liquid helium evaporation chamber, a first extraction pipe, a first circulating pump group, a first high-abundance recovery pipe and valve assembly, and a first low-abundance recovery pipe and valve assembly; The second helium-3 distillation circuit system also includes a second countercurrent heat exchanger, a second liquid helium evaporation chamber, a second extraction pipe, a second circulating pump set, a second high-abundance recovery pipe and valve assembly, and a second low-abundance recovery pipe and valve assembly; The first countercurrent heat exchanger includes a first inlet pipe and a first outlet pipe. One end of the first inlet pipe is connected to the outlet of the refrigeration device through a first inlet pipe and a valve assembly, and the other end of the first inlet pipe is connected to the first liquid helium evaporation chamber. One end of the first outlet pipe is connected to the first liquid helium evaporation chamber, and the other end of the first outlet pipe is connected to one end of the first extraction pipe. The other end of the first extraction pipe is connected to a first circulation pump group. The first circulation pump group is connected to a first gas cylinder and a second gas cylinder through a first high abundance recovery pipe and a valve assembly and a first low abundance recovery pipe and a valve assembly, respectively. The second countercurrent heat exchanger includes a second inlet pipe and a second outlet pipe. One end of the second inlet pipe is connected to the outlet of the refrigeration device through a second inlet pipe and a valve assembly, and the other end of the second inlet pipe is connected to the second liquid helium evaporation chamber. One end of the second outlet pipe is connected to the second liquid helium evaporation chamber, and the other end of the second outlet pipe is connected to one end of the second extraction pipe. The other end of the second extraction pipe is connected to a second circulation pump group. The second circulation pump group is connected to the first gas cylinder and the second gas cylinder through a second high abundance recovery pipe and a valve assembly and a second low abundance recovery pipe and a valve assembly, respectively.

3. The continuously operating parallel helium-3 distillation system according to claim 1, characterized in that, The refrigeration device includes a refrigeration unit, a primary heat exchanger, a secondary heat exchanger, and a tertiary heat exchanger that are thermally connected to the refrigeration unit. The primary heat exchanger, the secondary heat exchanger, and the tertiary heat exchanger are connected in sequence. The first inlet pipe and valve assembly and the second inlet pipe and valve assembly are connected in parallel at the outlet of the tertiary heat exchanger.

4. A continuously operating parallel helium-3 distillation system according to claim 3, characterized in that, The continuously operating parallel helium-3 distillation system also includes a vacuum enclosure, a primary cold shield, a secondary cold shield, and a tertiary cold shield. The tertiary cold shield... The three-stage cold shield is installed outside the first countercurrent heat exchanger, the first liquid helium evaporation chamber, the second countercurrent heat exchanger, and the second liquid helium evaporation chamber. The secondary cold shield is installed outside the tertiary heat exchanger. The primary cold shield is installed outside the secondary heat exchanger. The vacuum enclosure is placed outside the first-stage heat exchanger.

5. A continuously operating parallel helium-3 distillation system according to claim 4, characterized in that, The continuously operating parallel helium-3 distillation system also includes a precooling system, which comprises a primary heat exchanger, a secondary heat exchanger, a precooling liquid pool, a third extraction pipe, a third circulating pump set, an inlet valve, a precooling gas cylinder, and an outlet valve. The second primary heat exchanger is located inside the vacuum enclosure and outside the first primary cold shield; the second secondary heat exchanger is located inside the first primary cold shield and outside the second secondary cold shield; and the precooling liquid pool is located inside the second secondary cold shield and outside the third primary cold shield. The precooling gas cylinder is connected to the first-stage heat exchanger 2 via an inlet valve. The first-stage heat exchanger 2, the second-stage heat exchanger 2, and the precooling liquid pool are connected in sequence. One end of the third exhaust pipe is connected to the outlet of the precooling liquid pool, and the other end is connected to the third circulation pump group. The other end of the third circulation pump group is connected to the precooling gas cylinder via an outlet valve.

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