Cryogenic removal method and device for hydrogen isotope gas in helium
By connecting a primary and a secondary adsorption bed in series with a low-temperature adsorption bed, the problem of removing hydrogen isotope impurities from helium was solved, achieving efficient and low-cost production of high-purity helium.
Patent Information
- Application Number
- CN202511513972.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-22
- Publication Date
- 2026-01-02
AI Technical Summary
Existing technologies are difficult to use efficiently and at low cost to remove high levels of hydrogen isotope impurities from helium. The process is complex and cannot produce high-purity helium continuously for extended periods.
A primary and secondary adsorption bed are connected in series. The primary adsorption bed adsorbs hydrogen isotopes at low temperature, while the secondary adsorption bed further purifies the helium and hydrogen isotope impurities at even lower temperatures, thus achieving the production of high-purity helium.
It achieves efficient and simple hydrogen isotope removal, reduces equipment costs, simplifies operation procedures, and ensures continuous production of high-purity helium.
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Figure CN121243928A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of helium purification, in particular to a method and device for removing hydrogen isotopes from helium. BACKGROUND
[0002] It is relatively mature to use low-temperature rectification or chemical reaction to prepare pure helium in the field of helium purification, but such methods depend on the chemical reactivity of impurity gases, have high requirements for catalysts or adsorbents, and are relatively complex and costly. It is also relatively mature to remove impurity gases such as water, carbon dioxide, carbon monoxide, nitrogen, and methane using adsorbents. However, for raw gas with high hydrogen isotope impurity content, it is difficult to quickly prepare high-purity helium (for example, in a deuterium-tritium fusion device, helium is used as a coolant, and the working conditions require rapid purification), and related process technologies cannot meet the requirements; the continuous production of hydrogen isotope removal schemes through chemical reactions is limited by the chemical reaction limit, and frequent regeneration or replacement is required, impurity substances are difficult to separate and recover, and the process is complex.
[0003] Therefore, developing a process method for efficiently and simply removing hydrogen isotope impurities to obtain high-purity helium is a problem of concern in the relevant industry. SUMMARY
[0004] The present application aims to solve the problem that it is difficult to remove high-content hydrogen isotopes (such as deuterium and tritium) in helium, the process is complex, the operation cost is high, and continuous production cannot be achieved for a long time, and provides a method and device for removing hydrogen isotope gases from helium.
[0005] To achieve the above technical purposes, the technical solution provided by the present application is as follows: A device for removing hydrogen isotope gases from helium, comprising a two-stage adsorption bed and a one-stage adsorption bed connected in sequence by a pipeline, wherein the two-stage adsorption bed is provided with a second low-temperature obtaining and control system, and the one-stage adsorption bed is provided with a first low-temperature obtaining and control system; The second low-temperature obtaining and control system is used for obtaining and maintaining the low temperature of the two-stage adsorption bed. The first low-temperature obtaining and control system is used for obtaining and maintaining the low temperature of the one-stage adsorption bed.
[0006] In a specific embodiment, the first adsorption bed and the second adsorption bed are both sealed containers containing adsorbent material. The first adsorption bed adsorbs helium, hydrogen isotopes and other impurity gases at a temperature below 40 K, and releases a large amount of helium gas when the temperature is raised to 76 K. The second adsorption bed adsorbs hydrogen isotopes and other impurity gases under a second low temperature condition. The gas released from the first adsorption bed is subjected to the second adsorption bed to adsorb residual impurity gases, and high-purity helium gas is obtained and finally filled into a product tank.
[0007] Further, the second low temperature obtaining and control system comprises a second low temperature head connected to the second adsorption bed; and the first low temperature obtaining and control system comprises a first low temperature head connected to the first adsorption bed.
[0008] Further, the second low temperature obtaining and control system further comprises a second temperature control system connected to the first temperature sensor and the second temperature sensor, the first temperature sensor being arranged at the upper end of the second adsorption bed, and the second temperature sensor being arranged at the lower end of the second adsorption bed.
[0009] Further, the second temperature control system is further connected to the second low temperature head.
[0010] Further, the first low temperature obtaining and control system further comprises a first temperature control system connected to the third temperature sensor and the fourth temperature sensor, the third temperature sensor being arranged at the upper end of the first adsorption bed, and the fourth temperature sensor being arranged at the lower end of the first adsorption bed.
[0011] Further, the first temperature control system is further connected to the first low temperature head.
[0012] Further, a product gas tank is further provided, and the product gas tank is provided with a first pressure sensor.
[0013] In a specific embodiment, the product gas tank is further provided with a product gas tank valve.
[0014] Further, a raw material gas tank is further provided, and the raw material gas tank is provided with a second pressure sensor.
[0015] In a specific embodiment, the raw material gas tank is further provided with a raw material gas tank valve.
[0016] The application further provides a method for removing hydrogen isotope gas from helium gas by deep cooling, comprising the following steps: Step 1: first, evacuate the first adsorption bed and the second adsorption bed to better than 10 Pa under a heating temperature of 400-450°C, and close the adsorption bed valve; then place the first and second adsorption beds in a low temperature obtaining and control system, and open a vacuum system to evacuate the entire purification device to 1 Pa; Step 2: fill raw helium gas containing hydrogen isotope gas with different concentrations into a raw material gas tank; Step 3: The cold trap temperature of the primary adsorption bed is reduced to below 40K and the cold trap temperature of the secondary adsorption bed is reduced to 150K to 77K through the first low temperature acquisition and control system. Step 4: Introduce the gas from the raw material gas tank into the primary adsorption bed, and close the gas source valve after the gas adsorption capacity of the primary adsorption bed does not exceed 90% of its maximum adsorption capacity. Step 5: Slowly raise the temperature of the primary adsorption bed to 76K. The raw gas flows into the product tank after being purified by the primary and secondary adsorption beds. Step 6: After the temperature of the primary adsorption bed reaches the target temperature and the pressure does not rise significantly, close the valves of the secondary adsorption bed and the product tank. Step 7: Repeat steps 4-7. After multiple cycles, if the increase in the equilibrium pressure value in the next cycle does not exceed 10% compared to the previous purification operation in step 6, replace the product tank until production is complete. Step 8: When the amount of gas adsorbed by the primary adsorption bed in step 4 drops to about 50% of its maximum adsorption value, the primary adsorption bed and the secondary adsorption bed are reactivated, and steps 1 to 7 are repeated from step 1.
[0017] The activation process of the primary and secondary adsorption beds involves evacuating the primary and secondary adsorption beds to a pressure better than 10 Pa at a heating temperature of 400℃-450℃, and then closing the adsorption bed valves.
[0018] Furthermore, in step 1, the primary and secondary adsorption beds are filled with adsorption material, which is a molecular sieve.
[0019] Molecular sieves include one or more of 4A, 5A, and 13X.
[0020] In a specific embodiment, the helium feedstock gas contains hydrogen isotope gas and may also contain impurity gases such as water, carbon dioxide, carbon monoxide, methane, nitrogen, and oxygen.
[0021] The present invention has the following beneficial effects: 1. The present invention uses a primary adsorption bed and a secondary adsorption bed connected in series to adsorb hydrogen isotope gas step by step: the primary adsorption bed can handle higher concentrations of impurities, and the secondary adsorption bed performs fine treatment to ensure that the hydrogen isotope content in the outlet helium is extremely low, meeting the high purity requirements. 2. The primary adsorption bed first adsorbs a large amount of raw material gas at a temperature of 40K. When the temperature rises to about 76K, it releases a large amount of helium gas, which acts as a pump for the helium gas, eliminating the need for a circulating pump, thus making the equipment cheaper and easier to operate.
[0022] 3. The adsorption bed of the present invention can be regenerated simply by heating and evacuating, without the introduction of additional reactants, and the impurity gas can be released in its original state, which is convenient for collection and post-processing. Due to the simplicity and high reversibility of the process, no additional pumping equipment is required, which is convenient for organizing continuous production. It also has a high tolerance for impurity content and stable product quality. Attached Figure Description
[0023] Figure 1 This is a structural diagram of Embodiment 1 of the present invention; In the diagram: Vacuum pump 11, valve 12, vacuum gauge 13, product gas tank 2, first pressure sensor 21, product gas tank valve 22, raw material gas tank 3, second pressure sensor 31, raw material gas tank valve 32, second cryogenic acquisition and control system 4, second cryogenic head 44, secondary adsorption bed 5, first valve 51, second valve 52, third valve 53, first temperature sensor 42, second temperature sensor 43, first cryogenic acquisition and control system 7, first cryogenic head 74, primary adsorption bed 6, fourth valve 61, third temperature sensor 72, fourth temperature sensor 73 Detailed Implementation
[0024] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0026] Example like Figure 1 As shown, a cryogenic removal device for hydrogen isotope gas in helium includes... Vacuum pump 11, valve 12, and vacuum gauge 13 are connected by pipelines to provide a vacuum environment; A secondary adsorption bed 5 and a primary adsorption bed 6 are connected in sequence; wherein, a second low temperature acquisition and control system 4 is provided in the secondary adsorption bed 5, and a first low temperature acquisition and control system 7 is provided in the primary adsorption bed 6; The second low-temperature acquisition and control system 4 is used for the acquisition and maintenance of low temperature in the secondary adsorption bed 5; The first low-temperature acquisition and control system 7 is used for acquiring and maintaining the low temperature of the primary adsorption bed 6.
[0027] In a specific embodiment, the second low-temperature acquisition and control system 4 includes a second low-temperature head 44, which is connected to the secondary adsorption bed 5; the first low-temperature acquisition and control system 7 includes a first low-temperature head 74, which is connected to the primary adsorption bed 6.
[0028] In a specific embodiment, the second low-temperature acquisition and control system 4 also includes a second temperature control system 41. The second temperature control system 41 is connected to the first temperature sensor 42 and the second temperature sensor 43. The first temperature sensor 42 is disposed at the upper end of the secondary adsorption bed 5, and the second temperature sensor 43 is disposed at the lower end of the secondary adsorption bed 5.
[0029] The purpose of setting the first temperature sensor 42 and the second temperature sensor 43 in the secondary adsorption bed 5 is to measure the temperature at both ends of the adsorption bed. Because the lower end of the adsorption bed is connected to the low temperature head during operation, the temperature drops first and then is transmitted to the upper end. The two temperature sensors are set to monitor the temperature change of the adsorption bed.
[0030] In a specific embodiment, the second temperature control system 41 is also connected to the second cryogenic head 44.
[0031] Similarly, the first low-temperature acquisition and control system 7 also includes a first temperature control system 71, which is connected to a third temperature sensor 72 and a fourth temperature sensor 73. The third temperature sensor 72 is located at the upper end of the primary adsorption bed 6, and the fourth temperature sensor 73 is located at the lower end of the primary adsorption bed 6.
[0032] In a specific embodiment, the first temperature control system 71 is also connected to the first low-temperature head 74.
[0033] In a specific embodiment, a product tank 2 is also included, and a first pressure sensor 21 is provided on the product gas tank 2.
[0034] In a specific embodiment, a raw material gas tank 3 is also included, and a second pressure sensor 31 is provided on the raw material gas tank 3.
[0035] A method for cryogenic removal of hydrogen isotope gas from helium includes the following steps: Step 1: First, evacuate the primary adsorption bed 6 and the secondary adsorption bed 5 to a pressure better than 10 Pa at a heating temperature of 400℃. Then, close valve 61 of adsorption bed 6 and valves 51 and 52 of adsorption bed 5. Next, place the primary and secondary adsorption beds in the low temperature acquisition and control system and turn on the vacuum system to evacuate the entire purification device to 1 Pa. Step 2: Fill the raw material helium gas containing different concentrations of deuterium into the raw material gas tank 3; Step 3: The cold trap temperature of the primary adsorption bed is reduced to (30±10) K by the first low-temperature acquisition and control system; the cold trap temperature of the secondary adsorption bed is reduced to (90±10) K by the second low-temperature acquisition and control system; specifically, the low temperature is obtained by a refrigeration unit, which is existing equipment. Step 4: Open the raw material gas tank valve 32, the third valve 53, and the fourth valve 61 to introduce the gas in the raw material gas tank 3 into the primary adsorption bed 6. After the amount of gas adsorbed by the primary adsorption bed 6 does not exceed 90% of its maximum adsorption capacity, close the raw material gas source valve 32. Step 5: Slowly raise the temperature of the primary adsorption bed to about 76K, open the third valve 53, open the first valve 51 and the second valve 52, and the gas flows into the product gas tank 2 after being purified by the primary adsorption bed and the secondary adsorption bed. Step 6: After the temperature of the primary adsorption bed 6 reaches the target temperature and the pressure does not rise significantly, the first valve 51, the second valve 52, and the product gas tank valve 22 are activated. Step 7: Repeat steps 4-7. After multiple cycles, if the increase in the equilibrium pressure value in the next cycle does not exceed 10% compared to the previous purification operation in step 6, replace the product tank until production is complete. Step 8: When the amount of gas adsorbed by the primary adsorption bed in step 4 drops to about 50% of its maximum adsorption value, the primary adsorption bed and the secondary adsorption bed are reactivated, and steps 1 to 7 are repeated from step 1.
[0036] In a specific embodiment, in step 1, the primary adsorption bed and the secondary adsorption bed are filled with adsorption material, which is 4A molecular sieve.
[0037] The product gas obtained by the above method is shown in Table 1. The purity of the product gas can reach 99.995%.
[0038] Table 1. Product gas obtained after one round of purification treatment of raw gas Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
[0039] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.
Claims
1. A cryogenic removal device for hydrogen isotope gas in helium, characterized in that, include A secondary adsorption bed (5) and a primary adsorption bed (6) are connected sequentially by pipelines; wherein, the secondary adsorption bed (5) is equipped with a second low temperature acquisition and control system (4), and the primary adsorption bed (6) is equipped with a first low temperature acquisition and control system (7). The second low-temperature acquisition and control system (4) is used for the acquisition and maintenance of low temperature in the secondary adsorption bed (5); The first low-temperature acquisition and control system (7) is used for the acquisition and maintenance of low temperature in the primary adsorption bed (6).
2. The cryogenic removal device for hydrogen isotope gas in helium according to claim 1, characterized in that, The second low-temperature acquisition and control system (4) includes a second low-temperature head (44), which is connected to a secondary adsorption bed (5); the first low-temperature acquisition and control system (7) includes a first low-temperature head (74), which is connected to a primary adsorption bed (6).
3. The cryogenic removal device for hydrogen isotope gas in helium according to claim 2, characterized in that, The second low-temperature acquisition and control system (4) also includes a second temperature control system (41), which is connected to a first temperature sensor (42) and a second temperature sensor (43). The first temperature sensor (42) is located at the upper end of the secondary adsorption bed (5), and the second temperature sensor (43) is located at the lower end of the secondary adsorption bed (5).
4. The cryogenic removal device for hydrogen isotope gas in helium according to claim 3, characterized in that, The second temperature control system (41) is also connected to the second cryogenic head (44).
5. The cryogenic removal apparatus for hydrogen isotope gas in helium according to claim 2, characterized in that, The first low-temperature acquisition and control system (7) also includes a first temperature control system (71), which is connected to a third temperature sensor (72) and a fourth temperature sensor (73). The third temperature sensor (72) is located at the upper end of the primary adsorption bed (6), and the fourth temperature sensor (73) is located at the lower end of the primary adsorption bed (6).
6. The cryogenic removal apparatus for hydrogen isotope gas in helium according to claim 5, characterized in that, The first temperature control system (71) is also connected to the first cryogenic head (74).
7. The cryogenic removal apparatus for hydrogen isotope gas in helium according to claim 1, characterized in that, It also includes a product gas tank (2), on which a first pressure sensor (21) is provided.
8. The cryogenic removal apparatus for hydrogen isotope gas in helium according to claim 1, characterized in that, It also includes a raw material gas tank (3), on which a second pressure sensor (31) is provided.
9. The cryogenic removal apparatus for hydrogen isotope gas in helium according to claim 1, characterized in that, It also includes a vacuum pump (11), valves (12), and vacuum gauges (13) connected by pipelines to provide a vacuum environment.
10. A method for cryogenic removal of hydrogen isotope gas from helium using a cryogenic removal apparatus for hydrogen isotope gas in helium as described in any one of claims 1-9, characterized in that, Includes the following steps: Step 1: First, evacuate the primary and secondary adsorption beds to a pressure better than 10 Pa at a heating temperature of 400℃-450℃, and then close the adsorption bed valves; then place the primary and secondary adsorption beds in the low temperature acquisition and control system, and turn on the vacuum pump 11 to evacuate the entire purification device to 1 Pa. Step 2: Fill the raw material helium gas containing different concentrations of hydrogen isotope gas into the raw material gas tank; Step 3: Reduce the cold trap temperature of the primary adsorption bed to below 40K and the cold trap temperature of the secondary adsorption bed to between 150K and 77K. Step 4: Introduce the gas from the raw material gas tank into the primary adsorption bed, and close the gas source valve after the gas adsorption capacity of the primary adsorption bed does not exceed 90% of its maximum adsorption capacity. Step 5: Slowly raise the temperature of the primary adsorption bed to 76K. The raw gas flows into the product tank after being purified by the primary and secondary adsorption beds. Step 6: After the temperature of the primary adsorption bed reaches the target temperature and the pressure does not rise significantly, close the valves of the secondary adsorption bed and the product tank. Step 7: Repeat steps 4-7. After multiple cycles, if the increase in the equilibrium pressure value in the next cycle does not exceed 10% compared to the previous purification operation in step 6, replace the product tank until production is complete. Step 8: When the amount of gas adsorbed by the primary adsorption bed in step 4 drops to about 50% of its maximum adsorption value, the primary adsorption bed and the secondary adsorption bed are reactivated, and steps 1 to 7 are repeated from step 1.
11. The method for cryogenic removal of hydrogen isotope gas from helium according to claim 10, characterized in that, In step 1, the primary adsorption bed and the secondary adsorption bed are filled with adsorption material, which is a molecular sieve, including one or more of 4A, 5A, and 13X.