Low temperature gas separation device and low temperature gas separation method

Abstract

The present application relates to a low-temperature gas separation device and a low-temperature gas separation method, and belongs to the technical field of rare gas separation. The low-temperature gas separation device includes: a raw gas container, which is used to store a first mixed gas including a target gas and a plurality of impurity gases; a first gas separator, which has a first separation chamber for accommodating gas, the first separation chamber is connected to the raw gas container, and is used to receive the first mixed gas flowing into the raw gas container, and control the temperature to between a first preset temperature and a second preset temperature; a second gas separator, which has a second separation chamber for accommodating gas, the second separation chamber is connected to the first separation chamber, and is used to receive the second mixed gas flowing into the first gas separator, and control the temperature to between a third preset temperature and a fourth preset temperature; the third preset temperature is higher than the fourth preset temperature, and the third preset temperature is lower than the second preset temperature. The technical solution of the present application has the characteristics of more controllable separation and low cost.

Description

Technical Field

[0001] The present application relates to the technical field of rare gas separation, and in particular to a low-temperature gas separation device and a low-temperature gas separation method. Background Art

[0002] The tail gas of special industries (such as nuclear industry) contains a certain amount of rare gases (such as helium, krypton, xenon, etc.), and its content is thousands of times higher than that of air components, which has a certain recovery value. In scientific research, there are also many needs for tail gas recovery, separation, radiation research, etc. After these tail gases are treated by relevant chemical processes, after discharging a large amount of conventional impurity gases such as oxygen, nitrogen, argon, carbon, sulfur, etc., they can retain a high content of rare gases (such as a large amount of remaining helium, and trace amounts of krypton or xenon in helium).

[0003] Since rare gases are chemically very inactive, they are difficult to purify or separate stably through conventional chemical means. Also, due to their small quantity and great difficulty in separation, they are less economical and are not suitable for the preliminary processes of scientific research or industrial processing. Summary of the invention

[0004] In view of this, the present application provides a low-temperature gas separation device and a low-temperature gas separation method to solve at least one problem existing in the background technology.

[0005] To achieve the above purpose, the technical solution of this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a low-temperature gas separation device, comprising:

[0007] A raw gas container for storing a first mixed gas including a target gas and a plurality of impurity gases;

[0008] A first gas separator, comprising a first separation chamber for accommodating gas, the first separation chamber being connected to the raw gas container, for receiving the first mixed gas flowing into the raw gas container, and controlling the temperature to between a first preset temperature and a second preset temperature, so as to condense the impurity gas having a condensation temperature higher than the first preset temperature, and the uncondensed gas forms a second mixed gas and continues to flow backward; the first preset temperature is higher than the second preset temperature, and the condensation temperature of the target gas is lower than the second preset temperature;

[0009] The second gas separator has a second separation chamber for accommodating gas, the second separation chamber is connected to the first separation chamber, and is used to receive the second mixed gas flowing into the first gas separator, and control the temperature to between a third preset temperature and a fourth preset temperature, so as to condense the target gas whose condensation temperature is higher than the third preset temperature, and the uncondensed gas flows out of the second separation chamber through the outlet of the second gas separator; the third preset temperature is higher than the fourth preset temperature, and the third preset temperature is lower than the second preset temperature; the condensation temperature of the impurity gas in the second mixed gas is lower than the fourth preset temperature; the first preset temperature, the second preset temperature, the third preset temperature and the fourth preset temperature all belong to the low temperature range, and the low temperature range is 4K-153K.

[0010] Optionally, the first gas separator comprises:

[0011] A first heat exchanger is made of a first material having a thermal conductivity greater than 200 W / (m·K) and has the first separation chamber;

[0012] a first refrigerator, in thermal contact with the first heat exchanger, for reducing the temperature in the first separation chamber;

[0013] a first temperature sensor, used to measure the temperature in the first separation chamber to adjust the operation of the first refrigerator;

[0014] The second gas separator comprises:

[0015] A second heat exchanger is made of a first material having a thermal conductivity greater than 200 W / (m·K) and has the second separation chamber;

[0016] a second refrigerator in thermal contact with the second heat exchanger for reducing the temperature in the second separation chamber;

[0017] The second temperature sensor is used to measure the temperature in the second separation chamber to adjust the operation of the second refrigerator.

[0018] Optionally, the first gas separator further comprises:

[0019] a first heater, in thermal contact with the first heat exchanger, for increasing the temperature in the first separation chamber;

[0020] The second gas separator also includes:

[0021] The second heater is in thermal contact with the second heat exchanger and is used to increase the temperature in the second separation chamber.

[0022] Optionally, the first material is oxygen-free copper.

[0023] Optionally, the low-temperature gas separation device further comprises:

[0024] An analyzer is connected to the first separation chamber and the second separation chamber, and is used to analyze the components of the gas flowing out of the first separation chamber and the second separation chamber to adjust the values ​​of the first preset temperature, the second preset temperature, the third preset temperature and / or the fourth preset temperature.

[0025] Optionally, a plurality of heat exchange fins are installed in the first separation chamber, and a plurality of gas flow channels are formed between the plurality of heat exchange fins.

[0026] Optionally, the shape of the heat exchange fin is cylindrical, and the cylinder extends along the first direction; multiple heat exchange fins are spaced apart in the second direction, and the diameters of the heat exchange fins are different, and the space between the multiple heat exchange fins constitutes the gas flow channel; the first direction is the direction of the airflow, and the second direction is a direction perpendicular to the first direction.

[0027] Optionally, a spiral protrusion is further provided on the outer circumferential surface of the heat exchange fin to increase the contact area between the heat exchange fin and the gas.

[0028] Optionally, a plurality of heat exchange fins are installed in the second separation chamber, and a plurality of gas flow channels are formed between the plurality of heat exchange fins; a heat exchange plate perpendicular to the first direction is installed in the gas flow channel, the heat exchange plate has a plurality of through holes, and the aperture of the through holes is less than 1 mm; the first direction is the direction of the airflow.

[0029] Optionally, the heat exchange plate is a metal substrate prepared by an electrodeposition process or a sintering process, and the through holes are formed at one time during the electrodeposition process or the sintering process.

[0030] Optionally, the low-temperature gas separation device further comprises:

[0031] A vacuum box having a vacuum chamber, wherein the first heat exchanger and the second heat exchanger are both located in the vacuum chamber; the refrigerator and the temperature sensor are at least partially located in the vacuum chamber to be in thermal contact with the heat exchanger; the refrigerator includes the first refrigerator and the second refrigerator, and the temperature sensor includes the first temperature sensor and the second temperature sensor.

[0032] In a second aspect, an embodiment of the present application provides a low-temperature gas separation method, which is implemented by any one of the low-temperature gas separation devices described above; the method comprises:

[0033] Controlling the temperature in the first separation chamber to between a first preset temperature and a second preset temperature;

[0034] Controlling the temperature in the second separation chamber to between a third preset temperature and a fourth preset temperature;

[0035] Controlling the passage between the raw gas container and the first gas separator to open;

[0036] controlling the passage between the first gas separator and the second gas separator to open;

[0037] The outlet of the second gas separator is controlled to be open.

[0038] Optionally, the first gas separator comprises: a first heat exchanger having the first separation chamber; a first refrigerator in thermal contact with the first heat exchanger; a first temperature sensor for measuring the temperature in the first separation chamber;

[0039] The second gas separator comprises: a second heat exchanger having the second separation chamber; a second refrigerator in thermal contact with the second heat exchanger; and a second temperature sensor for measuring the temperature in the second separation chamber;

[0040] The controlling the temperature in the first separation chamber to a temperature between the first preset temperature and the second preset temperature, and the controlling the temperature in the second separation chamber to a temperature between the third preset temperature and the fourth preset temperature both include:

[0041] Starting the first refrigerator and the second refrigerator to reduce the temperature of the first separation chamber and the second separation chamber;

[0042] The temperatures of the first separation chamber and the second separation chamber are measured by temperature sensors to adjust the operation of the refrigerator; the temperature sensors include the first temperature sensor and the second temperature sensor.

[0043] Optionally, the first gas separator further comprises: a first heater in thermal contact with the first heat exchanger;

[0044] The second gas separator further includes: a second heater in thermal contact with the second heat exchanger;

[0045] The controlling the temperature in the first separation chamber to a temperature between a first preset temperature and a second preset temperature, and the controlling the temperature in the second separation chamber to a temperature between a third preset temperature and a fourth preset temperature, further comprises:

[0046] Starting the heater to increase the temperature of the first separation chamber and the second separation chamber; the heater includes the first heater and the second heater;

[0047] The temperatures of the first separation chamber and the second separation chamber are measured by a temperature sensor to adjust the operation of the refrigerator and the heater.

[0048] Optionally, the low-temperature gas separation device further comprises: an analyzer, connected to the first separation chamber and the second separation chamber, for performing component analysis on the gas flowing out of the first separation chamber and the second separation chamber;

[0049] The method further comprises:

[0050] An analysis result of the analyzer is obtained, and the values ​​of the first preset temperature, the second preset temperature, the third preset temperature and / or the fourth preset temperature are adjusted according to the analysis result.

[0051] The low-temperature gas separation device and low-temperature gas separation method provided in the embodiments of the present application include: a raw gas container for storing a first mixed gas including a target gas and a plurality of impurity gases; a first gas separator having a first separation chamber for accommodating gas, the first separation chamber being connected to the raw gas container for receiving the first mixed gas flowing into the raw gas container, and controlling the temperature to between a first preset temperature and a second preset temperature, so as to condense the impurity gas having a condensation temperature higher than the first preset temperature, and the uncondensed gas forming a second mixed gas continues to flow backward; the first preset temperature is higher than the second preset temperature, and the condensation temperature of the target gas is lower than the second preset temperature; a second gas separator having a second separation chamber for accommodating gas The second separation chamber is connected to the first separation chamber, and is used for receiving the second mixed gas flowing into the first gas separator, and controlling the temperature to between a third preset temperature and a fourth preset temperature, so as to condense the target gas whose condensation temperature is higher than the third preset temperature, and the uncondensed gas flows out of the second separation chamber through the outlet of the second gas separator; the third preset temperature is higher than the fourth preset temperature, and the third preset temperature is lower than the second preset temperature; the condensation temperature of the impurity gas in the second mixed gas is lower than the fourth preset temperature; the first preset temperature, the second preset temperature, the third preset temperature and the fourth preset temperature all belong to the low temperature range, and the low temperature range is 4K-153K. It can be seen that the low-temperature gas separation device and low-temperature gas separation method of the embodiment of the present application are provided with two gas separators, and both gas separators have a separation chamber for accommodating gas, and the temperature in the two separation chambers is reduced to a low temperature range, wherein the temperature of the first separation chamber is higher than the condensation temperature of the target gas, and the impurity gas with a condensation temperature higher than the target gas can be condensed in the first separation chamber and separated from the target gas; the temperature of the second separation chamber is lower than the condensation temperature of the target gas, and the target gas can be condensed in the second separation chamber, and the impurity gas with a condensation temperature lower than the target gas can be separated from the target gas. Since a physical method is used, the separation is more controllable and the cost is low. Therefore, the low-temperature gas separation device and low-temperature gas separation method of the embodiment of the present application have the characteristics of more controllable separation and low cost.

[0052] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0054] Figure 1 A schematic diagram of a low-temperature gas separation device provided in Example 1 of the present application;

[0055] Figure 2 This is a schematic flow chart of the low-temperature gas separation method provided in Example 2 of the present application.

[0056] Description of reference numerals:

[0057] 10. Raw gas container; 20. First gas separator; 21. First heat exchanger; 22. First refrigerator; 30. Second gas separator; 31. Second heat exchanger; 32. Second refrigerator; 40. Analyzer; 51. Vacuum box; 52. Vacuum pump; 61. Tail gas channel; 62. First recovery channel; 63. Second recovery channel; 64. Vacuum pump; 65. Buffer tank; 66. Impurity removal channel; 67. Pressure reducing valve; 68. Flow controller; 69. Pressure gauge. DETAILED DESCRIPTION

[0058] In order to make the technical solutions and beneficial effects of the present application more obvious and easy to understand, the following is a detailed description by listing specific embodiments. The drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which the present application belongs.

[0059] In the description of the present application, terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of simplified description of the present application, and do not indicate that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and should not be understood as a limitation on the present application.

[0060] In this application, the terms "first" and "second" are used only for the purpose of clear description and should not be understood as the relative importance of the indicated features or the number of the indicated technical features. Therefore, the features defined as "first" and "second" can explicitly include at least one of the features. In the description of this application, "multiple" means at least two, such as two, three, etc.; "several" means at least one, such as one, two, three, etc., unless otherwise clearly and specifically defined.

[0061] In this application, unless otherwise clearly defined, the terms "install", "connect", "connect", "fix", "set", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0062] In the present application, unless otherwise clearly defined, a first feature being “on”, “above”, “above”, “below”, “below”, “below” or “below” a second feature may mean that the first feature is in direct contact with the second feature, or the first feature and the second feature are in indirect contact with each other through an intermediate medium. Moreover, a first feature being “on”, “above” or “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than the horizontal height of the second feature. A first feature being “below”, “below” or “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0063] In order to thoroughly understand the present application, detailed steps and detailed structures will be presented in the following description to illustrate the technical solution of the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementation methods.

[0064] The inventors of this application discovered during research and development that due to the extremely inactive chemical properties of rare gases, it is difficult to stably purify or separate them through conventional chemical means. Furthermore, due to the small amount and great difficulty in separation, the economic efficiency is poor and they are not suitable for the preliminary processes of scientific research or industrial processing.

[0065] Therefore, through further research and development, the inventors found that the condensation temperature of rare gases is relatively low, which is quite different from the condensation temperature of impurity gases. Therefore, the following technical solution is proposed. Example 1

[0066] The present application provides a low temperature gas separation device. Figure 1 , the low temperature gas separation device comprises:

[0067] The raw gas container 10 is used to store a first mixed gas including a target gas and a plurality of impurity gases;

[0068] The first gas separator 20 has a first separation chamber for accommodating gas, the first separation chamber is connected to the raw gas container 10, and is used to receive the first mixed gas flowing into the raw gas container 10, and control the temperature to between a first preset temperature and a second preset temperature, so as to condense the impurity gas whose condensation temperature is higher than the first preset temperature, and the uncondensed gas forms a second mixed gas and continues to flow backward; the first preset temperature is higher than the second preset temperature, and the condensation temperature of the target gas is lower than the second preset temperature;

[0069] The second gas separator 30 has a second separation chamber for accommodating gas, the second separation chamber is connected to the first separation chamber, and is used to receive the second mixed gas flowing into the first gas separator 20, and control the temperature to between a third preset temperature and a fourth preset temperature, so as to condense the target gas whose condensation temperature is higher than the third preset temperature, and the uncondensed gas flows out of the second separation chamber through the outlet of the second gas separator 30; the third preset temperature is higher than the fourth preset temperature, and the third preset temperature is lower than the second preset temperature; the condensation temperature of the impurity gas in the second mixed gas is lower than the fourth preset temperature; the first preset temperature, the second preset temperature, the third preset temperature and the fourth preset temperature all belong to the low temperature range, and the low temperature range is 4K-153K.

[0070] It can be understood that the raw gas container 10 can be a container with a certain pressure, such as a steel cylinder, to compress the gas.

[0071] It can be understood that both the first separation chamber and the second separation chamber perform gas separation by controlling the temperature, so except for the air inlet and the air outlet, the others are all closed to make the temperature relatively stable.

[0072] The raw gas container 10 and the first gas separator 20, as well as the first gas separator 20 and the second gas separator 30 can be connected by pipelines, and necessary valves can be provided in the pipelines, which will not be described in detail.

[0073] It can be understood that the condensation temperature is the temperature at which a substance changes from a gaseous state to a liquid state. For example, if the condensation temperature of a substance is higher than the temperature in the separation chamber, the substance will change to a liquid state, otherwise it will remain a gas. The first gas separator 20 and the second gas separator 30 may be collectively referred to as a gas separator, and the first separation chamber and the second separation chamber may be collectively referred to as a separation chamber.

[0074] The target gas is the gas that needs to be separated, and all gases other than the target gas are impurity gases.

[0075] It can be understood that, since the condensation temperature of the target gas is lower than the second preset temperature, the target gas is maintained in a gaseous state in the first gas separator 20 .

[0076] It can be understood that, since the condensation temperature of the target gas is higher than the third preset temperature, the target gas is converted into a liquid state in the second gas separator 30 and is retained in the second gas separator 30. When the second gas separator 30 is full or the raw gas container 10 is empty, the separation operation stops. The liquid state of the target gas can be taken out from the second separator.

[0077] K is the unit of Kelvin temperature, one of the basic units of the International System of Units (SI). The Kelvin temperature scale is established using an ideal gas, starting from absolute zero. Every change of 1K is equivalent to a change of 1℃, and its zero point is called absolute zero. According to kinetic theory, when the temperature is at absolute zero, the kinetic energy of gas molecules is zero. For convenience, the scale unit of the Kelvin thermometer is consistent with the scale unit on the Celsius thermometer, that is, one degree on the Kelvin thermometer is equal to one degree on the Celsius thermometer, the freezing point of water is 0℃ on the Celsius thermometer, and 273.15K on the Kelvin thermometer. 4K-153K is equivalent to minus 269.15℃-minus 120.15℃.

[0078] The low-temperature gas separation device of the embodiment of the present application is provided with two gas separators, and both gas separators have a separation chamber for accommodating gas, and the temperature in the two separation chambers is reduced to a low-temperature range, wherein the temperature of the first separation chamber is higher than the condensation temperature of the target gas, and the impurity gas with a condensation temperature higher than the target gas can be condensed in the first separation chamber and separated from the target gas; the temperature of the second separation chamber is lower than the condensation temperature of the target gas, and the target gas can be condensed in the second separation chamber, and the impurity gas with a condensation temperature lower than the target gas can be separated from the target gas. Since a physical method is adopted, the separation is more controllable and the cost is low.

[0079] In some other embodiments of the present application, the first gas separator 20 includes:

[0080] The first heat exchanger 21 is made of a first material having a thermal conductivity greater than 200 W / (m·K) and has the first separation chamber;

[0081] a first refrigerator 22, thermally contacting the first heat exchanger 21, for reducing the temperature in the first separation chamber;

[0082] a first temperature sensor (not shown in the figure), used to measure the temperature in the first separation chamber to adjust the operation of the first refrigerator 22;

[0083] The second gas separator 30 comprises:

[0084] The second heat exchanger 31 is made of a first material having a thermal conductivity greater than 200 W / (m·K) and has the second separation chamber;

[0085] a second refrigerator 32, in thermal contact with the second heat exchanger 31, for reducing the temperature in the second separation chamber;

[0086] The second temperature sensor (not shown in the figure) is used to measure the temperature in the second separation chamber to adjust the operation of the second refrigerator 32 .

[0087] The two gas separators are provided with refrigerators respectively, which can cool down the temperature respectively, and the temperature control is more accurate. The first refrigerator 22 and the second refrigerator 32 are collectively referred to as refrigerators. The refrigerator can be a GM refrigerator, which is a Gifford-McMahon refrigerator, which is a regenerative low-temperature refrigerator that achieves refrigeration by compressing and expanding the gas.

[0088] Both heat exchangers are made of a first material with good thermal conductivity to improve heat conduction efficiency and reduce energy consumption. The first heat exchanger 21 and the second heat exchanger 31 are collectively referred to as heat exchangers.

[0089] The temperature sensor can measure the temperature in the separation chamber immediately to adjust the refrigerator. The first temperature sensor and the second temperature sensor are collectively referred to as temperature sensors.

[0090] In some other embodiments of the present application, the first gas separator 20 further includes:

[0091] a first heater (not shown in the figure), thermally contacting the first heat exchanger 21, for increasing the temperature in the first separation chamber;

[0092] The second gas separator 30 further comprises:

[0093] The second heater (not shown in the figure) is in thermal contact with the second heat exchanger 31 to increase the temperature in the second separation chamber.

[0094] Since the refrigeration capacity of the refrigerator is very large, for example, the separation chamber can be reduced from room temperature to 4K. Therefore, the deviation of the refrigeration temperature is relatively large, resulting in inaccurate temperature in the separation chamber. The heater is provided to more accurately control the temperature in the separation chamber. The first heater and the second heater can be collectively referred to as heaters.

[0095] In some other embodiments of the present application, the first material is oxygen-free copper.

[0096] The thermal conductivity of oxygen-free copper is usually between 350-400W / (m·K), so it can further improve the heat conduction efficiency and reduce energy consumption.

[0097] In some other embodiments of the present application, the low temperature gas separation device further comprises:

[0098] The analyzer 40 is connected to the first separation chamber and the second separation chamber, and is used to analyze the components of the gas flowing out of the first separation chamber and the second separation chamber to adjust the values ​​of the first preset temperature, the second preset temperature, the third preset temperature and / or the fourth preset temperature.

[0099] Through the analyzer 40, it is possible to more accurately understand whether the preset temperature in the separation chamber has achieved the expected effect, for example, whether the first separation chamber has condensed the preset impurity gas, and whether the second separation chamber has condensed the target gas, so as to adjust the temperature of the separation chamber according to the situation. The preset impurity gas is a gas whose condensation temperature is higher than the condensation temperature of the target gas.

[0100] It can be understood that one analyzer 40 can be provided in each of the first separation chamber and the second separation chamber.

[0101] In some other embodiments of the present application, a plurality of heat exchange fins are installed in the first separation chamber, and a plurality of gas flow channels are formed between the plurality of heat exchange fins.

[0102] In this way, the gas can fully contact the heat exchanger and quickly drop to the same temperature as the separation chamber.

[0103] It can be understood that the heat exchange fins are the heat exchanger mentioned above, or the heat exchange fins are a part of the heat exchanger.

[0104] In some other embodiments of the present application, the shape of the heat exchange fin is cylindrical, and the cylinder extends along the first direction; a plurality of heat exchange fins are spaced apart in the second direction, and the diameters of the heat exchange fins are different, and the space between the plurality of heat exchange fins constitutes the gas flow channel; the first direction is the direction of the airflow, and the second direction is a direction perpendicular to the first direction.

[0105] The cylindrical shape has a larger surface area, which is conducive to the full contact between the heat exchange fins and the gas. In addition, the diameters of the heat exchange fins are different, which can make full use of the space of the separation cavity and maximize the surface area of ​​the heat exchange fins.

[0106] In some other embodiments of the present application, a spiral protrusion is further provided on the outer circumferential surface of the heat exchange fin to increase the contact area between the heat exchange fin and the gas.

[0107] In this way, the surface area of ​​the heat exchange fins can be further increased, that is, the contact area between the heat exchange fins and the gas can be increased, thereby improving the heat exchange efficiency.

[0108] In some other embodiments of the present application, a plurality of heat exchange fins are installed in the second separation chamber, and a plurality of gas flow channels are formed between the plurality of heat exchange fins; the gas flow channels are installed with a heat exchange plate perpendicular to the first direction, the heat exchange plate has a plurality of through holes, and the aperture of the through holes is less than 1 mm; the first direction is the direction of the airflow.

[0109] It can be understood that in this embodiment, the heat exchanger includes a heat exchange plate in addition to the heat exchange fins mentioned above.

[0110] This embodiment further increases the contact area between the gas and the heat exchanger based on the technical solution of the heat exchange fins in the previous text.

[0111] Without limitation, a plurality of through holes with a pore size less than 1 mm is referred to as a microporous structure in this embodiment. Compared with heat exchange fins, the microporous structure can allow air to have more sufficient thermal contact with the heat exchanger. Moreover, since only the target gas needs to be condensed in the second separation chamber, the through holes will not be blocked due to excessive condensation.

[0112] In some other embodiments of the present application, the heat exchange plate is a metal substrate prepared by an electrodeposition process or a sintering process, and the through holes are formed once in the electrodeposition process or the sintering process.

[0113] Electrodeposition or sintering processes can form a large number of microporous structures, which are lower in cost than cutting, casting or stamping processes. In addition, the heat exchange plate formed by the electrodeposition process or sintering process has a large number of through holes extending in different directions, which greatly increases the inner wall area of ​​the through holes; in addition, in addition to forming through holes, a large number of blind holes are also formed, further increasing the surface area of ​​the heat exchange plate. These features increase the contact area between the heat exchange plate and the gas, and improve the efficiency of heat exchange.

[0114] Specifically, the metal matrix is ​​a copper matrix, which has better thermal conductivity and corrosion resistance.

[0115] In some other embodiments of the present application, the low temperature gas separation device further comprises:

[0116] The vacuum box 51 has a vacuum chamber, in which the first heat exchanger 21 and the second heat exchanger 31 are both located; the refrigerator and the temperature sensor are at least partially located in the vacuum chamber to be in thermal contact with the heat exchanger; the refrigerator includes the first refrigerator 22 and the second refrigerator 32, and the temperature sensor includes the first temperature sensor and the second temperature sensor.

[0117] In the vacuum chamber, the leakage of cold in the heat exchanger to the outside can be better reduced, or the conduction of heat from the outside into the heat exchanger can be reduced, making the temperature in the heat exchanger more stable.

[0118] In some other embodiments of the present application, the low temperature gas separation device further comprises:

[0119] The vacuum pump 52 is used to form or maintain the vacuum degree in the vacuum chamber.

[0120] The tail gas passage 61 is used to discharge the tail gas flowing out of the second separator.

[0121] The first recovery channel 62 is used to connect the second separation chamber and the raw gas container 10. The impurity gas flowing out of the second separation chamber can return to the raw gas container 10 to separate other gases or be used for other purposes.

[0122] The second recycling channel 63 is used to connect the first separation chamber and the raw gas container 10, and the second mixed gas flowing out of the first separation chamber can return to the raw gas container 10. For example, after being analyzed by the analyzer 40, if the second mixed gas flowing out of the first separation chamber does not meet the requirements, it can be returned to the raw gas container 10 for further separation. The second recycling channel 63 and the first recycling channel 62 can share a portion.

[0123] The vacuum pump 64 provides power for recovering the gas in the first recovery channel 62 and the second recovery channel 63 .

[0124] The buffer tank 65 is used to temporarily store gas during the recovery process.

[0125] The impurity removal channel 66 is connected to the first recovery channel 62, and can directly discharge the impurity gas in the second separation chamber, for example, the gas flowing out of the second separation chamber is directly discharged when there is no other use. The impurity removal channel 66 is also connected to the first separation chamber, and can discharge the impurity gas in the first separation chamber, for example, after analysis by the analyzer 40, the gas composition discharged from the first separation chamber does not meet the requirements.

[0126] The pressure reducing valve 67 is used to reduce the pressure of the gas flowing out of the raw gas container 10 and then flow it into the separation chamber.

[0127] The flow controller 68 is used to control and measure the amount of gas flowing into the separation chamber.

[0128] The pressure gauge 69 is used to monitor the gas pressure in the pipeline.

[0129] Multiple valves can be respectively arranged in multiple channels. The valves can be electric valves or manual valves. The valves are not marked by reference numerals in the drawings. Example 2

[0130] The present application also provides a low temperature gas separation method, which is implemented by the low temperature gas separation device described in Example 1. Figure 2 , the cryogenic gas separation method comprises:

[0131] Step 801: Control the temperature in the first separation chamber to between a first preset temperature and a second preset temperature;

[0132] Step 802: controlling the temperature in the second separation chamber to between a third preset temperature and a fourth preset temperature;

[0133] Step 803: Control the passage between the raw gas container and the first gas separator to open;

[0134] Step 804: Control the passage between the first gas separator and the second gas separator to open;

[0135] Step 805: Control the outlet of the second gas separator to open.

[0136] The low-temperature gas separation method of the embodiment of the present application is provided with two gas separators, and both gas separators have a separation chamber for accommodating gas, and the temperature in the two separation chambers is reduced to a low-temperature range, wherein the temperature of the first separation chamber is higher than the condensation temperature of the target gas, and the impurity gas with a condensation temperature higher than the target gas can be condensed in the first separation chamber and separated from the target gas; the temperature of the second separation chamber is lower than the condensation temperature of the target gas, and the target gas can be condensed in the second separation chamber, and the impurity gas with a condensation temperature lower than the target gas can be separated from the target gas. Since a physical method is adopted, the separation is more controllable and the cost is low.

[0137] In some other embodiments of the present application, the first gas separator 20 includes: a first heat exchanger 21 having the first separation chamber; a first refrigerator 22 in thermal contact with the first heat exchanger 21; and a first temperature sensor for measuring the temperature in the first separation chamber.

[0138] The second gas separator 30 includes: a second heat exchanger 31 having the second separation chamber; a second refrigerator 32 in thermal contact with the second heat exchanger 31; and a second temperature sensor for measuring the temperature in the second separation chamber.

[0139] The controlling the temperature in the first separation chamber to a temperature between the first preset temperature and the second preset temperature, and the controlling the temperature in the second separation chamber to a temperature between the third preset temperature and the fourth preset temperature both include:

[0140] Starting the first refrigerator 22 and the second refrigerator 32 to reduce the temperature of the first separation chamber and the second separation chamber;

[0141] The temperatures of the first separation chamber and the second separation chamber are measured by temperature sensors to adjust the operation of the refrigerator; the temperature sensors include the first temperature sensor and the second temperature sensor.

[0142] The two gas separators are equipped with refrigerators respectively, which can cool down the temperature separately, and the temperature control is more accurate. The temperature sensor can measure the temperature in the separation chamber at the first time to adjust the refrigerator. The first temperature sensor and the second temperature sensor are collectively referred to as temperature sensors.

[0143] In some other embodiments of the present application, the first gas separator 20 further includes: a first heater, thermally contacting the first heat exchanger 21;

[0144] The second gas separator 30 further includes: a second heater in thermal contact with the second heat exchanger 31 .

[0145] The controlling the temperature in the first separation chamber to a temperature between a first preset temperature and a second preset temperature, and the controlling the temperature in the second separation chamber to a temperature between a third preset temperature and a fourth preset temperature, further comprises:

[0146] Starting the heater to increase the temperature of the first separation chamber and the second separation chamber; the heater includes the first heater and the second heater;

[0147] The temperatures of the first separation chamber and the second separation chamber are measured by a temperature sensor to adjust the operation of the refrigerator and the heater.

[0148] Since the refrigeration capacity of the refrigerator is very large, for example, the separation chamber can be cooled from room temperature to 4K. Therefore, the deviation of the refrigeration temperature is relatively large, resulting in inaccurate temperature in the separation chamber. The heater is set to more accurately control the temperature in the separation chamber.

[0149] In some other embodiments of the present application, the low temperature gas separation device further comprises: an analyzer 40, connected to the first separation chamber and the second separation chamber, for analyzing the components of the gas flowing out of the first separation chamber and the second separation chamber. The method further comprises:

[0150] The analysis result of the analyzer 40 is obtained, and the values ​​of the first preset temperature, the second preset temperature, the third preset temperature and / or the fourth preset temperature are adjusted according to the analysis result.

[0151] Through the analyzer 40, it is possible to more accurately understand whether the preset temperature in the separation chamber has achieved the expected effect, for example, whether the first separation chamber has condensed the preset impurity gas, and whether the second separation chamber has condensed the target gas, so as to adjust the temperature of the separation chamber according to the situation. The preset impurity gas is a gas whose condensation temperature is higher than the condensation temperature of the target gas.

[0152] The low-temperature gas separation method of the embodiment of the present application is provided with two gas separators, and both gas separators have a separation chamber for accommodating gas, and the temperature in the two separation chambers is reduced to a low-temperature range, wherein the temperature of the first separation chamber is higher than the condensation temperature of the target gas, and the impurity gas with a condensation temperature higher than the target gas can be condensed in the first separation chamber and separated from the target gas; the temperature of the second separation chamber is lower than the condensation temperature of the target gas, and the target gas can be condensed in the second separation chamber, and the impurity gas with a condensation temperature lower than the target gas can be separated from the target gas. Since a physical method is adopted, the separation is more controllable and the cost is low.

[0153] It should be understood that the above embodiments are exemplary and are not intended to include all possible implementations included in the claims. Various modifications and changes may be made on the basis of the above embodiments without departing from the scope disclosed in the present application. Similarly, the various technical features of the above embodiments may be arbitrarily combined to form other embodiments of the present application that may not be explicitly described. Therefore, the above embodiments only express several implementations of the present application and do not limit the scope of protection of the patent of this application.

Claims

1. A low temperature gas separation device, characterized in that: include: A raw gas container for storing a first mixed gas including a target gas and a plurality of impurity gases; A first gas separator, comprising a first separation chamber for accommodating gas, the first separation chamber being connected to the raw gas container, for receiving the first mixed gas flowing into the raw gas container, and controlling the temperature to between a first preset temperature and a second preset temperature, so as to condense the impurity gas having a condensation temperature higher than the first preset temperature, and the uncondensed gas forms a second mixed gas and continues to flow backward; the first preset temperature is higher than the second preset temperature, and the condensation temperature of the target gas is lower than the second preset temperature; the target gas is a rare gas; a second gas separator, comprising a second separation chamber for accommodating gas, the second separation chamber being connected to the first separation chamber, for receiving the second mixed gas flowing into the first gas separator, and controlling the temperature to between a third preset temperature and a fourth preset temperature, so as to condense the target gas having a condensation temperature higher than the third preset temperature, and the uncondensed gas flows out of the second separation chamber through the outlet of the second gas separator; The third preset temperature is higher than the fourth preset temperature, and the third preset temperature is lower than the second preset temperature; the condensation temperature of the impurity gas in the second mixed gas is lower than the fourth preset temperature; the first preset temperature, the second preset temperature, the third preset temperature and the fourth preset temperature all belong to the low temperature range, and the low temperature range is 4K-153K; A plurality of heat exchange fins are installed in the second separation chamber, and a plurality of gas flow channels are formed between the plurality of heat exchange fins; a heat exchange plate perpendicular to the first direction is installed in the gas flow channel; the heat exchange plate has a plurality of through holes, and the aperture of the through holes is less than 1 mm; the first direction is the direction of the airflow.

2. The low temperature gas separation device according to claim 1, characterized in that: The first gas separator comprises: A first heat exchanger is made of a first material having a thermal conductivity greater than 200 W / (m·K) and has the first separation chamber; a first refrigerator, in thermal contact with the first heat exchanger, for reducing the temperature in the first separation chamber; a first temperature sensor, used to measure the temperature in the first separation chamber to adjust the operation of the first refrigerator; The second gas separator comprises: A second heat exchanger is made of a first material having a thermal conductivity greater than 200 W / (m·K) and has the second separation chamber; a second refrigerator in thermal contact with the second heat exchanger for reducing the temperature in the second separation chamber; The second temperature sensor is used to measure the temperature in the second separation chamber to adjust the operation of the second refrigerator.

3. The low temperature gas separation device according to claim 2, characterized in that: The first gas separator also includes: a first heater, in thermal contact with the first heat exchanger, for increasing the temperature in the first separation chamber; The second gas separator also includes: The second heater is in thermal contact with the second heat exchanger and is used to increase the temperature in the second separation chamber.

4. The low temperature gas separation device according to claim 2, characterized in that: The first material is oxygen-free copper.

5. The low temperature gas separation device according to claim 1, characterized in that: The low temperature gas separation device also includes: An analyzer is connected to the first separation chamber and the second separation chamber, and is used to analyze the components of the gas flowing out of the first separation chamber and the second separation chamber to adjust the values ​​of the first preset temperature, the second preset temperature, the third preset temperature and / or the fourth preset temperature.

6. The low temperature gas separation device according to any one of claims 1 to 5, characterized in that: A plurality of heat exchange fins are installed in the first separation chamber, and a plurality of gas flow channels are formed between the plurality of heat exchange fins.

7. The low temperature gas separation device according to claim 6, characterized in that: The heat exchange fin is cylindrical in shape, and the cylinder extends along the first direction; a plurality of heat exchange fins are spaced apart in the second direction, and the diameters of the heat exchange fins are different, and the space between the plurality of heat exchange fins constitutes the gas flow channel; the first direction is the direction of the airflow, and the second direction is a direction perpendicular to the first direction.

8. The low temperature gas separation device according to claim 7, characterized in that: The outer circumferential surface of the heat exchange fin is also provided with a spiral protrusion to increase the contact area between the heat exchange fin and the gas.

9. The low temperature gas separation device according to claim 1, characterized in that: The heat exchange plate is a metal substrate prepared by an electrodeposition process or a sintering process, and the through hole is formed once in the electrodeposition process or the sintering process.

10. The low temperature gas separation device according to any one of claims 2 to 4, characterized in that: The low temperature gas separation device also includes: A vacuum box having a vacuum chamber, wherein the first heat exchanger and the second heat exchanger are both located in the vacuum chamber; the refrigerator and the temperature sensor are at least partially located in the vacuum chamber to be in thermal contact with the heat exchanger; the refrigerator includes the first refrigerator and the second refrigerator, and the temperature sensor includes the first temperature sensor and the second temperature sensor.

11. A method for low temperature separation of gas, characterized in that: The method is implemented by the low-temperature gas separation device according to any one of claims 1 to 10; the method comprises: Controlling the temperature in the first separation chamber to between a first preset temperature and a second preset temperature; Controlling the temperature in the second separation chamber to between a third preset temperature and a fourth preset temperature; Controlling the passage between the raw gas container and the first gas separator to open; controlling the passage between the first gas separator and the second gas separator to open; The outlet of the second gas separator is controlled to be open.

12. The low temperature gas separation method according to claim 11, characterized in that: The first gas separator comprises: a first heat exchanger having the first separation chamber; a first refrigerator in thermal contact with the first heat exchanger; a first temperature sensor for measuring the temperature in the first separation chamber; The second gas separator comprises: a second heat exchanger having the second separation chamber; a second refrigerator in thermal contact with the second heat exchanger; and a second temperature sensor for measuring the temperature in the second separation chamber; The controlling the temperature in the first separation chamber to a temperature between the first preset temperature and the second preset temperature, and the controlling the temperature in the second separation chamber to a temperature between the third preset temperature and the fourth preset temperature both include: Starting the first refrigerator and the second refrigerator to reduce the temperature of the first separation chamber and the second separation chamber; The temperatures of the first separation chamber and the second separation chamber are measured by temperature sensors to adjust the operation of the refrigerator; the temperature sensors include the first temperature sensor and the second temperature sensor.

13. The low temperature gas separation method according to claim 12, characterized in that: The first gas separator further includes: a first heater in thermal contact with the first heat exchanger; The second gas separator further includes: a second heater in thermal contact with the second heat exchanger; The controlling the temperature in the first separation chamber to a temperature between a first preset temperature and a second preset temperature, and the controlling the temperature in the second separation chamber to a temperature between a third preset temperature and a fourth preset temperature, further comprises: Starting the heater to increase the temperature of the first separation chamber and the second separation chamber; the heater includes the first heater and the second heater; The temperatures of the first separation chamber and the second separation chamber are measured by a temperature sensor to adjust the operation of the refrigerator and the heater.

14. The low temperature gas separation method according to claim 11, characterized in that: The low-temperature gas separation device further includes: an analyzer, connected to the first separation chamber and the second separation chamber, for analyzing the components of the gas flowing out of the first separation chamber and the second separation chamber; The method further comprises: An analysis result of the analyzer is obtained, and the values ​​of the first preset temperature, the second preset temperature, the third preset temperature and / or the fourth preset temperature are adjusted according to the analysis result.

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