A wide abundance helium-3 enrichment system
By utilizing the principle of dilution refrigeration and low-temperature phase separation technology, combined with gas purity analysis, efficient and stable enrichment of helium-3 was achieved. This solved the problems of low helium-3 abundance and complex and uncontrollable devices in existing technologies, achieving a helium-3 enrichment rate of over 95%.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 粤港澳大湾区(广东)量子科学中心
- Filing Date
- 2025-08-21
- Publication Date
- 2026-07-31
AI Technical Summary
Existing helium-3 enrichment systems cannot achieve helium-3 enrichment with a wide range of abundance, and existing methods have problems such as low helium-3 abundance or complex and uncontrollable devices.
Employing the principle of a dilution refrigeration unit, this system combines a precooling device, an evaporation chamber, a heat exchanger, and a mixing chamber. By utilizing the phase separation phenomenon of mixed gases at low temperatures, helium-3 is separated and replenished within the evaporation chamber. Combined with a gas purity analysis and measurement device to control the gas intake valve, the system ensures that the helium-3 abundance is maintained at a high level.
Stable enrichment of helium-3 abundance was achieved, with an enrichment rate of over 95%. The system operated stably, the helium-3 abundance remained essentially unchanged, the inflow of helium-4 was avoided, and the device structure was simplified.
Smart Images
Figure CN224573224U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of gas separation, and in particular to a wide-abundance helium-3 enrichment system. Background Technology
[0002] Helium-3 gas plays a crucial role in fields such as neutron detection and quantum computing. However, with the increasingly tense international situation, my country's imports of helium-3 are dwindling. Helium-3 is vital for national defense security, and currently, my country relies entirely on imports for its high-purity helium-3.
[0003] Current domestic research mainly focuses on methods such as superleafing and thermal flushing. The principle of enriching helium-3 via superleafing is as follows: when the temperature of helium-4 drops below 2.17 K, it transforms into superfluid helium. Superfluid helium has no viscosity and can pass through devices with extremely small apertures, while helium-3, due to its viscosity, cannot pass through the superleaf. However, not all superfluid helium-4 will pass through the superleaf; this depends on the chemical potentials across the superleaf. When the chemical potentials across the superleaf reach equilibrium, the superfluid helium-4 can no longer flow through the entropy filter, and separation reaches its limit. Currently, the helium-3 enrichment achieved by this method is generally no higher than 4%. The principle of enriching helium-3 via thermal flushing is as follows: when the temperature of helium drops to 2.17 K, it transforms into superfluid helium. Superfluid helium consists of two fluids: a superfluid and a normal fluid. The superfluid has almost no viscosity, while the normal fluid has properties similar to ordinary fluids and is viscous. Helium-3 generally moves with the normal fluid. When heat is introduced at a point in superfluid helium, the superfluid moves towards the heated end, while the normal fluid and helium-3 move towards the cold end. Ultimately, helium-3 accumulates at the cold end. However, in this process, helium-3 remains in the superfluid helium-4; removing helium-3 also removes superfluid helium-4, making it difficult to control the abundance of helium-3 in the extracted gas. Currently, no system can achieve helium-3 enrichment with a wide range of abundance.
[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 broad abundance helium-3 enrichment system, which aims to solve the problem that the existing helium-3 enrichment system cannot obtain broad abundance helium-3 enrichment.
[0006] The technical solution of this utility model is as follows: A wide-abundance helium-3 enrichment system includes a raw gas conveying mechanism, a precooling device, an evaporation chamber, a heat exchange device, a mixing chamber, and a product collection mechanism. The evaporation chamber includes a first liquid inlet, a first liquid outlet, a second liquid inlet, and a gas outlet. The first liquid outlet and the second liquid inlet are spaced apart at the bottom of the evaporation chamber, and the gas outlet is located at the top of the evaporation chamber. The heat exchange device includes heat exchange channel one and heat exchange channel two; The mixing chamber includes an inlet and an outlet, and a conduit extending through the outlet toward the bottom wall of the mixing chamber is provided inside the mixing chamber; One end of the precooling device is connected to the raw gas conveying mechanism and the other end is connected to the first liquid inlet of the evaporation chamber. One end of the heat exchange channel of the heat exchange device is connected to the first liquid outlet and the other end is connected to the inlet of the mixing chamber. One end of the heat exchange channel of the heat exchange device is connected to the outlet of the mixing chamber and the other end is connected to the second liquid inlet. The air outlet is connected to the raw gas conveying mechanism and the product collection mechanism, respectively.
[0007] Optionally, the precooling device includes a first precooling heat exchanger, a second precooling heat exchanger, and a third precooling heat exchanger connected sequentially along the air intake direction.
[0008] Optionally, the broad-abundance helium-3 enrichment system further includes a flow resistance located between the precooling device and the first inlet.
[0009] Optionally, the broad abundance helium-3 enrichment system further includes a gas purity analysis and measurement device and a gas sampling valve located between the gas outlet and the product collection mechanism.
[0010] Beneficial Effects: This invention liquefies the helium mixture by inputting it entirely into a pre-cooling device, then introduces it into an evaporation chamber. The temperature of the evaporation chamber is set at 0.5-1.5K. The helium-3 abundance in the solution within the evaporation chamber is approximately 1%, and the helium-3 abundance in the vapor is approximately 95% or higher. Finally, the vapor from the evaporation chamber is drawn from the outlet into a product collection mechanism, achieving a broad-abundance enrichment of helium-3. This is because when the temperature is below 0.87K, the mixed gas in the mixing chamber undergoes phase separation: the upper layer is a dense phase, mainly composed of helium-3; the lower layer is a dilute phase, mainly composed of helium-4. During the refrigeration process, helium-3 continuously flows from the dense phase to the dilute phase, and helium-3 from the dilute phase continuously enters the evaporation chamber through a conduit, replenishing the helium-3 in the evaporation chamber. Therefore, even though helium-3 is continuously removed from the evaporation chamber, the helium-3 concentration remains essentially constant, thus maintaining a high helium-3 abundance (e.g., above 95%) in the vapor within the evaporation chamber. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the structure of Example 1. Detailed Implementation
[0012] This invention provides a broad-abundance helium-3 enrichment 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 of this invention and are not intended to limit it.
[0013] 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.
[0014] Currently available helium-3 enrichment systems are suitable for helium-3 abundances of approximately 1 ppm, with a theoretical enrichment efficiency of about 5%, making it impossible to enrich helium-3 at higher abundances. While higher abundance helium-3 enrichment can theoretically be achieved through methods such as cryogenic distillation, these methods involve complex experimental setups and uncontrollable experimental results. No domestic research has yet demonstrated their ability to enrich helium-3 across a wide range of abundances.
[0015] Based on this, this embodiment provides a broad-abundance helium-3 enrichment system, such as... Figure 1 As shown, it includes a raw gas conveying mechanism 1, a pre-cooling device 2, an evaporation chamber 3, a heat exchange device 4, a mixing chamber 5, and a product collection mechanism 6. The evaporation chamber 3 includes a first liquid inlet 3-1, a first liquid outlet 3-2, a second liquid inlet 3-3, and a gas outlet 3-4. The first liquid outlet 3-2 and the second liquid inlet 3-3 are spaced apart at the bottom of the evaporation chamber 3, and the gas outlet 3-4 is located at the top of the evaporation chamber 3. The heat exchange device 4 includes a heat exchange channel 4-1 and a heat exchange channel 4-2; The mixing chamber 5 includes an inlet 5-1 and an outlet 5-2, and a conduit 5-3 is provided inside the mixing chamber 5, which passes through the outlet 5-2 and extends toward the bottom wall of the mixing chamber 5; One end of the precooling device 2 is connected to the raw gas conveying mechanism 1 and the other end is connected to the first liquid inlet 3-1 of the evaporation chamber 3. One end of the heat exchange channel 4-1 of the heat exchange device 4 is connected to the first liquid outlet 3-2 and the other end is connected to the inlet 5-1 of the mixing chamber 5. One end of the heat exchange channel 4-2 of the heat exchange device 4 is connected to the outlet 5-2 of the mixing chamber 5 and the other end is connected to the second liquid inlet 3-3. The air outlets 3-4 are respectively connected to the raw gas conveying mechanism 1 and the product collection mechanism 6.
[0016] It should be noted that this embodiment is based on the principle of a dilution refrigerator, enriching helium-3 with an abundance of 10% to 20% to obtain helium-3 gas with an abundance of approximately 99%. The 10% to 20% helium-3 is transported from the raw gas conveying mechanism 1 into the system, then enters the pre-cooling device 2, and subsequently passes through the evaporation chamber 3, the heat exchange device 4, and the mixing chamber 5. Because the temperature is below 0.87K, the mixed gas in the mixing chamber will exhibit phase separation: the upper layer is a dense phase, mainly composed of helium-3; the lower layer is a dilute phase, mainly composed of helium-4. During the refrigeration process, helium-3 continuously moves from the dense phase to the dilute phase, and helium-3 in the dilute phase continuously enters the evaporation chamber along the conduit 5-3, replenishing the helium-3 in the evaporation chamber. Therefore, even though helium-3 is continuously removed from the evaporation chamber, the helium-3 concentration in the evaporation chamber remains essentially unchanged, thus maintaining the vapor helium-3 abundance in the evaporation chamber at a high level, such as above 95%. Furthermore, the lower part of the evaporation chamber contains a helium-mixed solution, while the upper part contains vapor. The helium-3 concentration in the vapor is very high. During stable operation of the dilution refrigeration unit, the product collection mechanism 6 removes the gas from the upper part of the evaporation chamber. Controlling the intake and extraction rates ensures a stable system cycle. As vapor is removed from the evaporation chamber, the helium-3 in the evaporation chamber solution continuously evaporates, and helium-3 from the mixing chamber flows into the evaporation chamber to replenish it. During this process, the helium-3 abundance in both the solution and vapor in the evaporation chamber remains essentially constant until most of the helium-3 from the mixing chamber has been replenished to the evaporation chamber, and most of the helium-3 in the evaporation chamber has been removed. When the abundance of removed helium-3 falls below 95%, the gas extraction valve is closed, and the remaining gas is recovered to the original gas delivery mechanism for gas circulation. Helium-3 flows from the dilute phase to the evaporation chamber driven by osmotic pressure. Because helium-3 in the evaporation chamber continuously evaporates, it is constantly replenished. Meanwhile, helium-4 in the evaporation chamber hardly evaporates, and its chemical potential and other parameters remain almost constant. Without a chemical potential difference to drive helium-4 flow, no helium-4 flows in.
[0017] It should be noted that all of the above connections are gas connections, which can be made through conduits.
[0018] It should be noted that the lower end of the conduit 5-3 is positioned below the phase separation line, and preferably slightly above the bottom wall. The conduit can be welded to the inner wall of the mixing chamber 5.
[0019] Preferably, the heat exchange device can be a counter-current heat exchanger, a shell-and-tube heat exchanger, or a silver powder heat exchanger.
[0020] In one embodiment, the precooling device 2 includes a precooling heat exchanger 2-1, a precooling heat exchanger 2-2, and a precooling heat exchanger 2-3 connected sequentially along the air intake direction.
[0021] Preferably, the precooling heat exchanger 2-3 is a JT heat exchanger or a 1K liquid tank.
[0022] In one embodiment, the broad abundance helium-3 enrichment system further includes a flow resistance 7 disposed between the precooling device 2 and the first liquid inlet 3-1.
[0023] In one embodiment, the broad abundance helium-3 enrichment system further includes a gas purity analysis and measurement device 8 and a gas sampling valve 9 disposed between the gas outlet 3-4 and the product collection mechanism 6.
[0024] The gas purity analysis and measurement device 8 can select to open or close the gas sampling valve 9 based on the abundance of helium-3 measured by the gas purity analysis and measurement device 8. When the abundance of helium-3 extracted is less than 95%, the gas sampling valve 12 is closed.
[0025] Example 1 This embodiment provides a broad-abundance helium-3 enrichment system, such as Figure 1 As shown, it includes a raw gas conveying mechanism 1, a pre-cooling device 2, an evaporation chamber 3, a heat exchange device 4, a mixing chamber 5, and a product collection mechanism 6. The evaporation chamber 3 includes a first liquid inlet 3-1, a first liquid outlet 3-2, a second liquid inlet 3-3, and a gas outlet 3-4. The first liquid outlet 3-2 and the second liquid inlet 3-3 are spaced apart at the bottom of the evaporation chamber 3, and the gas outlet 3-4 is located at the top of the evaporation chamber 3. The heat exchange device 4 is a counter-current heat exchanger, which includes heat exchange channel 4-1 and heat exchange channel 4-2. The mixing chamber 5 includes an inlet 5-1 and an outlet 5-2, and a conduit 5-3 is provided inside the mixing chamber 5, which passes through the outlet 5-2 and extends toward the bottom wall of the mixing chamber 5; One end of the precooling device 2 is connected to the raw gas conveying mechanism 1 and the other end is connected to the first liquid inlet 3-1 of the evaporation chamber 3. One end of the heat exchange channel 4-1 of the heat exchange device 4 is connected to the first liquid outlet 3-2 and the other end is connected to the inlet 5-1 of the mixing chamber 5. One end of the heat exchange channel 4-2 of the heat exchange device 4 is connected to the outlet 5-2 of the mixing chamber 5 and the other end is connected to the second liquid inlet 3-3. The air outlets 3-4 are respectively connected to the raw gas conveying mechanism 1 and the product collection mechanism 6.
[0026] In this embodiment, the conduit 5-3 can be welded onto the outlet 5-2 and suspended in the mixing chamber 5.
[0027] The precooling device 2 described in this embodiment includes a precooling heat exchanger 2-1, a precooling heat exchanger 2-2, and a precooling heat exchanger 2-3 connected sequentially along the air intake direction.
[0028] In this embodiment, the precooling heat exchanger 3-2-3 is a JT heat exchanger or a 1K liquid tank.
[0029] In this embodiment, the heat exchange temperature of precooling heat exchanger 1 (2-1) is approximately 40K, the heat exchange temperature of precooling heat exchanger 2 (2-2) is approximately 4K, the heat exchange temperature of precooling heat exchanger 3 (2-3) is approximately 1K, the heat exchange temperature of evaporation chamber 3 is 0.3-1.5K, and the heat exchange temperature of mixing chamber (5) is approximately 10-500mK. Different types of dilution refrigeration machines have different temperatures. In this embodiment, the key temperature to compare is the temperature of the evaporation chamber.
[0030] The broad abundance helium-3 enrichment system described in this embodiment also includes a flow resistance 7 located between the precooling device 2 and the first liquid inlet 3-1.
[0031] The broad abundance helium-3 enrichment system described in this embodiment also includes a gas purity analysis and measurement device 8 and a gas sampling valve 9 located between the gas outlet 3-4 and the product collection mechanism 6.
[0032] The evaporator chamber has a cooling temperature range of 0.3K-1.5K.
[0033] The gas purity analysis and measurement device 8 can select to open or close the gas sampling valve 9 based on the abundance of helium-3 measured by the gas purity analysis and measurement device 8. When the abundance of helium-3 extracted is less than 95%, the gas sampling valve 12 is closed.
[0034] In this embodiment, the raw gas is a gas with a helium-3 abundance of approximately 20%. The helium-3 abundance in the gas is detected and measured by the gas purity analysis and measurement device 8. The helium-3 detection result during the collection process shows that the helium-4 purity is 1.995%, and the calculated helium-3 purity is 98%.
[0035] 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 broad-abundance helium-3 enrichment system, characterized in that, It includes a raw gas conveying mechanism, a pre-cooling device, an evaporation chamber, a heat exchange device, a mixing chamber, and a product collection mechanism; The evaporation chamber includes a first liquid inlet, a first liquid outlet, a second liquid inlet, and a gas outlet. The first liquid outlet and the second liquid inlet are spaced apart at the bottom of the evaporation chamber, and the gas outlet is located at the top of the evaporation chamber. The heat exchange device includes heat exchange channel one and heat exchange channel two; The mixing chamber includes an inlet and an outlet, and a conduit extending through the outlet toward the bottom wall of the mixing chamber is provided inside the mixing chamber; One end of the precooling device is connected to the raw gas conveying mechanism and the other end is connected to the first liquid inlet of the evaporation chamber. One end of the heat exchange channel of the heat exchange device is connected to the first liquid outlet and the other end is connected to the inlet of the mixing chamber. One end of the heat exchange channel of the heat exchange device is connected to the outlet of the mixing chamber and the other end is connected to the second liquid inlet. The air outlet is connected to the raw gas conveying mechanism and the product collection mechanism, respectively.
2. The broad-abundance helium-3 enrichment system according to claim 1, characterized in that, The precooling device includes three precooling heat exchangers connected sequentially along the air intake direction: precooling heat exchanger one, precooling heat exchanger two, and precooling heat exchanger three.
3. The broad-abundance helium-3 enrichment system according to claim 1, characterized in that, The broad-abundance helium-3 enrichment system also includes a flow resistance located between the precooling device and the first inlet.
4. The broad-abundance helium-3 enrichment system according to claim 1, characterized in that, The broad abundance helium-3 enrichment system also includes a gas purity analysis and measurement device and a gas sampling valve located between the gas outlet and the product collection mechanism.