Gas phase change purification device with wide temperature range selection
By combining a refrigeration unit and a temperature control system, a wide temperature range for gas purification and regeneration is achieved, solving the problems of large equipment size and long desorption time in traditional gas purification devices, and realizing an efficient and safe gas purification and regeneration process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CSIC PRIDE (NANJING) CRYOGENIC TECHNOLOGY CO LTD
- Filing Date
- 2026-01-20
- Publication Date
- 2026-04-14
AI Technical Summary
Traditional gas purification devices require frequent replenishment of liquid nitrogen, have long desorption times, occupy a large area, and can only operate in the 77K liquid nitrogen temperature range, making it difficult to effectively remove impurity gases such as neon.
Using a refrigeration unit as the cold source, combined with a temperature control system, it achieves a controllable step-by-step temperature-controlled purification process from 5K to 200K and a controllable regeneration process from 200K to 330K. The process involves step-by-step heat exchange and cooling through a cylinder heat exchanger and a cold head heat exchanger, followed by regeneration using a heater, which simplifies the process and reduces the equipment footprint.
It achieves gas purification with a simple process, compact equipment, and convenient operation, and can output ultra-high purity helium gas of not less than 6N, shortening desorption time, reducing equipment footprint, and avoiding the dangers of liquid nitrogen.
Smart Images
Figure CN121846831A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to gas separation and purification technology, and more particularly to a gas phase change purification device with a wide temperature range selectivity. Background Technology
[0002] Gases are indispensable substances in modern society. Based on their unique physical and chemical properties (such as combustion-supporting properties, inertness, low temperature, and density), they play a crucial role in human production and daily life, and are widely used in industrial manufacturing, medical and health care, scientific research, and other fields. With the development of technology, the requirements for gas purity are becoming increasingly stringent; therefore, gas separation and purification are particularly important in the field of gas analysis.
[0003] Traditional cryogenic gas purification methods primarily utilize liquid nitrogen as a cold source, employing cryogenic adsorption to remove impurities from helium. This typically involves two purifiers that are switched between each other. During purification, liquid nitrogen must be continuously replenished to the purifiers, and during desorption, the liquid nitrogen must be discharged followed by regeneration through heating. The purification process is quite cumbersome, and the equipment occupies a significant amount of space. Furthermore, because most gas adsorption devices use liquid nitrogen as a cold source, the temperature can only be maintained within the 77K liquid nitrogen temperature range, while some impurities mixed in helium, such as neon, require temperatures below 30K to be adsorbed and removed. Traditional adsorption purification equipment often requires external heat transfer devices for heat transfer during desorption to complete the regeneration process, further increasing space requirements, limiting the equipment's applicability, and resulting in long desorption times. Therefore, there is an urgent need to develop a purification device with a simple process, small footprint, and short desorption time. Summary of the Invention
[0004] Purpose of the invention: To address the shortcomings and defects of existing technologies, this invention provides a gas phase change purification device with a wide temperature range. The device employs stepwise temperature control during purification, with a controllable temperature of 5K-200K, and a controllable temperature of 200K-330K during regeneration. The process is simple, the structure is compact, and the operation is convenient. It can purify multi-component gases such as crude helium and output ultra-high purity helium with a purity of not less than 6N.
[0005] Technical solution: The present invention provides a gas phase change purification device with wide temperature range selection, characterized in that: it includes a refrigerator as a cold source and a temperature control system for stepwise control of the raw gas temperature. After the raw gas enters the two-stage positive pressure chamber, it passes through a cylinder heat exchanger, a cold head, and a cold head heat exchanger for stepwise heat exchange and cooling. The cylinder and the surface of the cold head are both equipped with heat exchangers. The temperature control system includes a temperature controller, a temperature sensor, and a host computer.
[0006] The positive pressure chamber includes a primary positive pressure chamber and a secondary positive pressure chamber.
[0007] The primary positive pressure chamber and the secondary positive pressure chamber are located inside the vacuum chamber.
[0008] The primary positive pressure chamber is equipped with a primary cold head, a primary cylinder heat exchanger, a first heater, and a first temperature sensor, and the primary cold head is equipped with a primary cold head heat exchanger; the secondary positive pressure chamber is equipped with a secondary cold head, a secondary cylinder heat exchanger, a second temperature sensor, and a second heater, and the secondary cold head is equipped with a secondary cold head heat exchanger; the temperature of the primary cold head can be reduced to a minimum of 40K, and the temperature of the secondary cold head can be reduced to a minimum of 5K.
[0009] The first temperature sensor is located at the first-stage cold head and connected to the temperature controller; the second temperature sensor is located at the second-stage cold head and connected to the temperature controller; the first-stage and second-stage cold heads are located at the cooling capacity output end of the refrigeration unit.
[0010] The first heater works with a temperature controller to control the temperature of the first-stage cold head, and the second heater works with a temperature controller to control the temperature of the second-stage cold head; both the first heater and the second heater are connected to the temperature controller.
[0011] The first heater and the second heater serve two purposes: firstly, to control the temperature of the primary and secondary cold heads in conjunction with the temperature controller during the purification process; and secondly, to act as a heat source during the regeneration process.
[0012] The primary cylinder heat exchanger, primary cold head heat exchanger, secondary cylinder heat exchanger, and secondary cold head heat exchanger are made of high thermal conductivity materials; preferably copper.
[0013] The top of the secondary positive pressure chamber is higher than the bottom of the primary positive pressure chamber, and the connection between the two forms a storage tank structure; the refrigeration unit is a GM refrigeration unit, a pulse tube refrigeration unit, or a Stirling refrigeration unit.
[0014] The raw material gas enters the primary positive pressure chamber and the secondary positive pressure chamber through the inlet. The primary positive pressure chamber and the secondary positive pressure chamber are arranged in a vacuum hood. The primary positive pressure chamber and the secondary positive pressure chamber contain a refrigerator. The primary cylinder and the secondary cylinder of the refrigerator are equipped with a primary cylinder heat exchanger and a secondary cylinder heat exchanger. The primary cold head and the secondary cold head are respectively equipped with a first temperature sensor, a second temperature sensor, a first heater, and a second heater. The lower surface of the primary cold head and the secondary cold head is equipped with a primary cold head heat exchanger and a secondary cold head heat exchanger. The processed raw material gas is led from the bottom of the secondary positive pressure chamber to the outlet through a pipeline and discharged.
[0015] Working Principle: During purification, the refrigeration unit acts as the cold source. Heat exchangers are distributed on the primary and secondary cold head cylinders of the refrigeration unit. A first temperature sensor and a first heater are installed at the primary cold head, and a second temperature sensor and a second heater are installed at the secondary cold head. The first and second heaters, in conjunction with a temperature controller, respectively control the temperature of the primary and secondary cold heads, with a temperature control accuracy of ±0.1K. As the raw gas sequentially passes through the primary cylinder heat exchanger, the primary cold head heat exchanger, the secondary cylinder heat exchanger, and the secondary cylinder heat exchanger, its temperature decreases stage by stage. Impurities, whose temperature is below their triple point, solidify and freeze in the heat exchangers, completing the purification process. During regeneration, the first and second heaters act as the heat source, raising the system temperature and causing the solidified impurities to vaporize and be discharged.
[0016] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) The present invention uses a refrigerator instead of liquid nitrogen as a cold source, which is safe to operate and allows the purification process to have a wide temperature range to choose from. With the temperature control system, the temperature can be controlled step by step. At the same time, the temperature can be controlled from 5 to 200K during the purification process and from 200 to 330K during the regeneration process; (2) The purification process of first-stage liquefaction and second-stage solidification is adopted, which increases the running time of the equipment and improves the production efficiency of the equipment; (3) The purification and regeneration processes are completed in one device. During purification, a refrigerator is used instead of liquid nitrogen as a cold source, and during regeneration, a heater is used instead of an external heat-conducting device as a heat source. The structure is compact, the equipment is small, and the process is simple. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of the present invention;
[0018] In the diagram, 1 represents the refrigeration unit; 101 represents the primary cold head; 102 represents the secondary cold head; 201 represents the primary cylinder heat exchanger; 202 represents the secondary cylinder heat exchanger; 3 represents the first heater; 4 represents the first temperature sensor; 5 represents the primary cold head heat exchanger; 601 represents the primary positive pressure chamber; 602 represents the secondary positive pressure chamber; 7 represents the second temperature sensor; 8 represents the second heater; 9 represents the secondary cold head heat exchanger; 10 represents the vacuum chamber; 11 represents the host computer; 12 represents the temperature controller; 13 represents the inlet; and 14 represents the outlet. Detailed Implementation
[0019] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0020] The gas phase change purification device with wide temperature range selection of the present invention includes a refrigerator 1 as a cold source and a temperature control system for stepwise control of the temperature of the raw gas. After the raw gas enters several stages of positive pressure chambers, it passes through a cylinder heat exchanger and a cold head heat exchanger for stepwise heat exchange and cooling. A cold head heat exchanger is provided on the surface of the cold head. The temperature control system includes a temperature controller 12, a temperature sensor, and a host computer 11. After the raw gas passes through the first-stage cylinder heat exchanger and the first-stage cold head heat exchanger, the temperature gradually decreases. Most of the impurity gas liquefies and flows into the storage tank at the junction of the first and second stage positive pressure chambers. The remaining gas continues to flow to the second-stage cold head. After passing through the second-stage cylinder heat exchanger and the second-stage cold head heat exchanger, the remaining impurity gas solidifies and freezes in the second-stage cylinder heat exchanger and the second-stage cold head heat exchanger, thereby completing the purification.
[0021] The positive pressure chamber of this invention includes a primary positive pressure chamber 601 and a secondary positive pressure chamber 602. The primary positive pressure chamber 601 and the secondary positive pressure chamber 602 are located inside a vacuum chamber 10. The primary positive pressure chamber 601 is equipped with a primary cold head 101, a primary cylinder heat exchanger 201, a first heater 3, and a first temperature sensor 4; the primary cold head 101 is also equipped with a primary cold head heat exchanger 5. The secondary positive pressure chamber 602 is equipped with a secondary cold head 102, a secondary cylinder heat exchanger 202, a second temperature sensor 7, and a second heater 8; the secondary cold head 102 is also equipped with a secondary cold head heat exchanger 9. The minimum temperature of the primary cold head 101 can be reduced to 40K, and the minimum temperature of the secondary cold head 102 can be reduced to 5K. The first temperature sensor 4 is located at the primary cold head 101 and connected to a temperature controller 12; the second temperature sensor 7 is located at the secondary cold head 102 and connected to a temperature controller 12; the primary cold head 101 and the secondary cold head 102 are located at the cooling capacity output end of the refrigerator 1. The first heater 3, in conjunction with the temperature controller 12, controls the temperature of the primary cold head 101, and the second heater 8, also in conjunction with the temperature controller 12, controls the temperature of the secondary cold head 102. Both the first heater 3 and the second heater 8 are connected to the temperature controller 12. One function of the first heater 3 and the second heater 8 is to control the temperature of the primary and secondary cold heads 101 and 102 in conjunction with the temperature controller 12 during the purification process; another function is to act as a heat source during the regeneration process. The host computer 11 provides closed-loop control of the temperatures of the primary and secondary cold heads. The primary cold head heat exchanger 5 is fastened between the primary cold head 101 and the primary positive pressure chamber 601.
[0022] The first-stage cylinder heat exchanger 201, the first-stage cold head heat exchanger 5, the second-stage cylinder heat exchanger 202, and the second-stage cold head heat exchanger 9 of the present invention have high thermal conductivity and are preferably made of copper; the top of the second-stage positive pressure chamber 602 is higher than the bottom of the first-stage positive pressure chamber 601, and a storage tank structure is formed at the connection between the two; the refrigeration machine 1 is a GM refrigeration machine, a pulse tube refrigeration machine, or a Stirling refrigeration machine.
[0023] In use, the raw material gas enters the primary positive pressure chamber 601 and the secondary positive pressure chamber 602 through the inlet 13. The primary positive pressure chamber 601 and the secondary positive pressure chamber 602 are arranged in the vacuum shroud 10. The primary positive pressure chamber 601 and the secondary positive pressure chamber 602 contain a refrigerator 1. The primary cylinder and the secondary cylinder of the refrigerator 1 are equipped with a primary cylinder heat exchanger 201 and a secondary cylinder heat exchanger 202. The primary cold head 101 and the secondary cold head 102 are respectively equipped with a first temperature sensor 4, a second temperature sensor 7, a first heater 3, and a second heater 8. The lower surface of the primary cold head 101 and the secondary cold head 102 is equipped with a primary cold head heat exchanger 5 and a secondary cold head heat exchanger 9. The processed raw material gas is led from the bottom of the secondary positive pressure chamber 602 to the outlet 14 through a pipeline and discharged.
[0024] Example: As shown in the figure, the gas purification and regeneration process is carried out in vacuum chamber 10. A refrigerator 1 is used instead of traditional liquid nitrogen as the cold source, allowing for a wide temperature range selection during the purification process and avoiding the dangers of frostbite and suffocation associated with liquid nitrogen. The refrigerator 1 can be a GM refrigerator, a pulse tube refrigerator, or a Stirling refrigerator. Preferably, a two-stage refrigeration system is selected to ensure refrigeration efficiency at deep cryogenic temperatures, especially suitable for gas purification, such as helium purification, which has high requirements for cryogenic technology. The cooling output of the refrigerator 1 includes a primary cold head 101 and a secondary cold head 102. The minimum temperature of the primary cold head 101 can be reduced to 40K, and the minimum temperature of the secondary cold head can be reduced to 5K. Through this "step-by-step pre-cooling" mode, the secondary cold head 102 does not need to be cooled directly from room temperature but rather "relays" the cooling on top of the primary cold head 101, significantly improving the refrigeration efficiency and stability at deep cryogenic temperatures.
[0025] The refrigeration unit 1 is equipped with a primary cylinder heat exchanger 201, a primary cold head heat exchanger 5, a secondary cylinder heat exchanger 202, and a secondary cold head heat exchanger 9. All of these heat exchangers have high thermal conductivity, and the preferred material is copper. The primary cylinder heat exchanger 201, the primary cold head heat exchanger 5, the secondary cylinder heat exchanger 202, and the secondary cold head heat exchanger 9 increase the gas cooling path and improve the cooling efficiency.
[0026] In this embodiment, a temperature control system is used to control the temperature of the primary and secondary cooling heads. A first temperature sensor 4 is installed at the primary cooling head 101, and a first heater 3 is fixed to the primary cooling head 101. Both the first temperature sensor 4 and the first heater 3 are externally connected to a temperature controller 12, which is controlled by a host computer 11. Similarly, a second temperature sensor 7 is installed at the secondary cooling head 102, and a second heater 8 is fixed to the secondary cooling head 102. Both the second temperature sensor 7 and the second heater 8 are externally connected to the temperature controller 12, which is controlled by the host computer 11. Different temperature control temperatures are set on the host computer interface. When the cooling energy is transferred to the first-stage cold head 101, the first temperature sensor 4 transmits the temperature signal to the temperature controller 12. The host computer 11 uses the temperature controller 12 to perform PID closed-loop control on the first temperature sensor 4 and the first heater 3 to control the temperature of the first-stage cold head 101. Similarly, the host computer 11 uses the temperature controller 12 to perform PID closed-loop control on the second temperature sensor 7 and the second heater 8 to control the temperature of the second-stage cold head 102. Since the cold source is provided by the refrigerator 1, the selectable temperature control range is very wide. With the temperature control system, the temperature can be controlled from 5 to 200K during the purification process and from 200K to 323K during the regeneration process. Furthermore, through step-by-step temperature control, the temperature in the positive pressure chamber also changes gradually with the temperature of the refrigerator cold head, that is, it gradually decreases from top to bottom, and the output is ultra-high purity helium with a purity of not less than 6N.
[0027] The raw material gas enters through gas inlet 13 and enters the primary purification chamber. In the primary positive pressure chamber 601, it comes into contact with the primary cylinder and the primary cylinder heat exchanger 201 for the first stage of cooling. The arrangement of the primary cylinder heat exchanger 201 increases the gas flow path and improves the cooling efficiency until it reaches the primary cold head 101. The temperature gradually decreases to the cold head temperature. During this process, most of the impurity gas temperature successively falls below its liquefaction point, and the impurity gas continuously liquefies and flows to the storage tank at the connection between the primary and secondary purification chambers. The remaining gas continues to enter the secondary purification chamber through the primary cold head heat exchanger 5. In the secondary purification chamber, it comes into contact with the secondary cylinder and the secondary cylinder heat exchanger 202 for the second stage of cooling. The arrangement of the secondary cylinder heat exchanger 202 increases the gas flow path. Therefore, during this process, the temperature of the remaining small part of the impurity gas gradually falls below its solidification temperature and continuously solidifies and freezes on the secondary cylinder heat exchanger 202, the secondary cold head 102, and the secondary cold head heat exchanger 9. The processed raw gas meets the ultrapure requirements and flows out of the purification system from the bottom pipeline of the secondary purification chamber to the product gas outlet 14.
[0028] After prolonged operation, impurity gases continuously freeze in the purification chamber, causing blockage. Regeneration is then necessary to enable reusability. The high-temperature regeneration process utilizes the first heater 3 and second heater 8, fastened to the primary and secondary cold heads 101 and 102, to provide heat instead of external heat transfer equipment. This results in a wider and higher temperature range for regeneration, significantly reducing equipment space and regeneration time. Temperature control parameters are set on the host computer 64 interface, controlling the temperature of the primary and secondary cold heads within a range of 200K-323K. After reaching the set temperature, the temperature is maintained for one hour. During this time, the liquefied impurity gases in the primary purification chamber and the frozen impurity gases in the secondary purification chamber continuously vaporize and sublimate, increasing the pressure in the pipeline. The high-pressure impurity gases are discharged from the product gas outlet 14. The regeneration and purification processes are carried out within the same purification equipment, simplifying the workflow, reducing equipment space and regeneration time, and demonstrating high versatility and promotional value.
[0029] This equipment can be used not only for industrial gas purification, but also as experimental equipment. Depending on the experimental needs, the temperature of the primary and secondary cold heads, the type of raw gas, and the inlet flow rate can be changed to verify the effect of different parameters on the purification effect and achieve the experimental purpose.
Claims
1. A gas phase change purification device with wide temperature range selectivity, characterized in that: It includes a refrigeration unit (1) as a cold source and a temperature control system for step-by-step control of the raw gas temperature. After the raw gas enters the two-stage positive pressure chamber, it passes through the cylinder heat exchanger, the cold head, and the cold head heat exchanger for step-by-step heat exchange and cooling. The cylinder and the cold head are both equipped with heat exchangers. The temperature control system includes a temperature controller (12), a temperature sensor, and a host computer (11).
2. The gas phase change purification apparatus with wide temperature range selection according to claim 1, characterized in that: The positive pressure chamber includes a primary positive pressure chamber (601) and a secondary positive pressure chamber (602).
3. The gas phase change purification apparatus with wide temperature range selection according to claim 2, characterized in that: The primary positive pressure chamber (601) and the secondary positive pressure chamber (602) are located inside the vacuum shroud (10).
4. The gas phase change purification apparatus with wide temperature range selection according to claim 2, characterized in that: The first-stage positive pressure chamber (601) is equipped with a first-stage cold head (101), a first-stage cylinder heat exchanger (201), a first heater (3) and a first temperature sensor (4), and the first-stage cold head (101) is equipped with a first-stage cold head heat exchanger (5); the second-stage positive pressure chamber (602) is equipped with a second-stage cold head (102), a second-stage cylinder heat exchanger (202), a second temperature sensor (7) and a second heater (8), and the second-stage cold head (102) is equipped with a second-stage cold head heat exchanger (9); the temperature of the first-stage cold head (101) can be reduced to a minimum of 40K, and the temperature of the second-stage cold head (102) can be reduced to a minimum of 5K.
5. The gas phase change purification apparatus with wide temperature range selection according to claim 4, characterized in that: The first temperature sensor (4) is located at the first-stage cold head (101) and connected to the temperature controller (12); the second temperature sensor (7) is located at the second-stage cold head (102) and connected to the temperature controller (12); the first-stage cold head (101) and the second-stage cold head (102) are located at the cooling output end of the refrigeration unit (1).
6. The gas phase change purification apparatus with wide temperature range selection according to claim 5, characterized in that: The first heater (3) works with the temperature controller (12) to control the temperature of the first-stage cold head (101), and the second heater (8) works with the temperature controller (12) to control the temperature of the second-stage cold head (102); both the first heater (3) and the second heater (8) are connected to the temperature controller (12).
7. The gas phase change purification apparatus with wide temperature range selection according to claim 6, characterized in that: The first heater (3) and the second heater (8) serve two purposes: firstly, to work with the temperature controller (12) to control the temperature of the first-stage cold head (101) and the second-stage cold head (102) during the purification process; secondly, to serve as a heat source during the regeneration process.
8. The gas phase change purification apparatus with wide temperature range selection according to claim 4, characterized in that: The first-stage cylinder heat exchanger (201), the first-stage cold head heat exchanger (5), the second-stage cylinder heat exchanger (202), and the second-stage cold head heat exchanger (9) are made of high thermal conductivity materials.
9. The gas phase change purification apparatus with wide temperature range selection according to claim 2, characterized in that: The top of the secondary positive pressure chamber (602) is higher than the bottom of the primary positive pressure chamber (601), and the connection between the two forms a storage tank structure; the refrigeration machine (1) is a GM refrigeration machine, a pulse tube refrigeration machine or a Stirling refrigeration machine.
10. The gas phase change purification apparatus with wide temperature range selection according to any one of claims 1-9, characterized in that: The raw material gas enters the primary positive pressure chamber (601) and the secondary positive pressure chamber (602) through the inlet (13). The primary positive pressure chamber (601) and the secondary positive pressure chamber (602) are arranged in the vacuum hood (10). The primary positive pressure chamber (601) and the secondary positive pressure chamber (602) contain a refrigerator (1). The primary cylinder and the secondary cylinder of the refrigerator (1) are equipped with a primary cylinder heat exchanger (201) and a secondary cylinder heat exchanger (202). The primary cold head (101) and the secondary cold head (102) are respectively equipped with a first temperature sensor (4), a second temperature sensor (7), a first heater (3), and a second heater (8). The primary cold head (101) and the secondary cold head (102) are equipped with a primary cold head heat exchanger (5) and a secondary cold head heat exchanger (9) on their lower surfaces. The processed raw material gas is led from the bottom of the secondary positive pressure chamber (602) to the outlet (14) through a pipeline and discharged.