Gas purification device and gas purification system

Abstract

The utility model provides a gas purification device and a gas purification system, and the gas purification device comprises a cold trap mechanism which comprises a cold trap main body which is installed on a cold head of a first refrigerating machine and forms heat conduction with the cold head so as to be cooled by the cold head to a first temperature suitable for adsorbing impurities; the vacuum cover covers the outer side of the cold trap main body, and a vacuum cavity suitable for being pumped to be in a vacuum state is limited in the vacuum cover, so that the cold trap main body is thermally isolated from the external environment; the pipeline mechanism comprises a first branch which is suitable for arranging the cold trap main body on a circulating pipeline of a gas source to be purified in parallel and is configured to be selectively communicated with the circulating pipeline; and the desorption mechanism is configured to respond to the cut-off state of the first branch, heat the cold trap main body to a second temperature suitable for desorbing the impurities, and extract the impurities in the cold trap main body.

Description

Technical Field

[0001] The utility model relates to the technical field of gas purification, in particular to a gas purification device and a gas purification system. Background Art

[0002] Gas purification devices with cold trap mechanisms as the main body are suitable for adsorbing impurities in gas under low temperature conditions and are widely used in the field of gas purification technology. For example, they can be used in the petrochemical industry to remove moisture, carbon dioxide and other heavy hydrocarbons in natural gas; they can be used in the pharmaceutical industry to remove unwanted byproducts and impurities in solvents and / or reactants; they can be used in the field of semiconductor technology to remove chlorine and / or hydrogen generated in silicon wafer production; they can be used in the field of low-temperature physics research to remove impurities in the working fluid of refrigeration equipment, etc.

[0003] Based on the different gases to be purified and the different impurities to be adsorbed, the gas purification device with the cold trap mechanism as the main body needs to be arranged under suitable low temperature conditions. In order to meet the low temperature conditions for adsorbing impurities, at present, the gas purification device (at least the cold trap mechanism) is mostly set in a dewar storing a cooling medium (such as liquid nitrogen), so that the cold trap mechanism is maintained in a low-temperature adsorption state. Such a gas purification device not only takes up a large space, but also requires frequent replenishment of the cooling medium. Moreover, in the actual operation process, in order to maintain the adsorption effect of the gas purification device, the cold trap mechanism needs to be cleaned regularly.

[0004] When cleaning the cold trap, in order to desorb the impurities adsorbed by the cold trap, the cold trap needs to be moved out of the cooling medium and heated to room temperature. Therefore, online cleaning cannot be performed in the dewar. In addition, in the process of removing the cold trap from the dewar, the cooling medium will be lost and there is a certain risk. Therefore, how to provide a gas purification device and gas purification system that occupies a small space and can be cleaned online has become a technical problem that needs to be solved urgently. Utility Model Content

[0005] In order to solve at least one of the above and other technical problems in the prior art, the utility model provides a gas purification device and a gas purification system.

[0006] An embodiment of the utility model provides a gas purification device, which is suitable for purifying the working medium of a gas source, and includes: a cold trap mechanism, including: a cold trap body, which is installed on a cold head of a first refrigerator and forms heat conduction with the above-mentioned cold head, so as to be cooled by the above-mentioned cold head to a first temperature suitable for adsorbing impurities; a vacuum cover, which is arranged on the outside of the above-mentioned cold trap body, and the above-mentioned vacuum cover defines a vacuum chamber suitable for being extracted to a vacuum state, so that the above-mentioned cold trap body is thermally isolated from the external environment; a pipeline mechanism, including: a first branch, which is suitable for setting the above-mentioned cold trap body in parallel on the circulation pipeline of the gas source to be purified, and is constructed to be selectively connected with the above-mentioned circulation pipeline; a desorption mechanism, which is constructed to heat the above-mentioned cold trap body to a second temperature suitable for desorbing impurities in response to the cut-off state of the above-mentioned first branch, and extract the impurities in the above-mentioned cold trap body.

[0007] According to an embodiment of the utility model, the desorption mechanism includes: a heating component, which is used to heat the cold trap body to the second temperature; and a first vacuum pump, which is connected to the cold trap body and is used to extract impurities desorbed from the cold trap body.

[0008] According to an embodiment of the utility model, the heating component is arranged in the cold head; the desorption mechanism also includes a temperature collection component communicatively connected to the heating component, which is suitable for collecting the temperature of the cold head and / or the cold trap body.

[0009] According to an embodiment of the utility model, the above-mentioned pipeline mechanism also includes a second branch arranged between the above-mentioned cold trap body and the above-mentioned circulation pipeline. The above-mentioned second branch connects the above-mentioned cold trap body and the above-mentioned circulation pipeline in response to the cut-off state of the above-mentioned first branch, so that the working fluid remaining in the above-mentioned cold trap body flows back to the above-mentioned circulation pipeline.

[0010] According to an embodiment of the utility model, the above-mentioned cold trap mechanism also includes an air inlet pipe and an air outlet pipe, the above-mentioned air inlet pipe is used as the air inlet end of the above-mentioned cold trap body, and the above-mentioned air outlet pipe is used as the air outlet end of the above-mentioned cold trap body; wherein the above-mentioned air inlet pipe and the above-mentioned air outlet pipe are arranged side by side to form heat conduction.

[0011] According to an embodiment of the utility model, the cold trap body includes a first portion close to the cold head and a second portion away from the cold head; wherein the first portion and the second portion are made of different materials, and the thermal conductivity of the first portion is higher than that of the second portion.

[0012] According to an embodiment of the utility model, an adsorption material is arranged in the cold trap body, and the adsorption material is at least filled in the first part.

[0013] An embodiment of the utility model also provides a gas purification system, comprising: at least one gas source to be purified; at least one gas purification device, wherein the first branch of the gas purification device is connected in parallel with the circulation pipeline of each of the gas sources, and is configured to be selectively connected to the circulation pipeline; and a second vacuum pump is connected to the vacuum cover of the gas purification device, and is suitable for pumping the vacuum chamber to a vacuum state; wherein the gas purification device is configured to adsorb impurities in the working fluid in response to the conduction state of the first branch, and is configured to desorb impurities in the cold trap body of the gas purification device in response to the cut-off state of the first branch.

[0014] According to an embodiment of the present invention, a gas purification system includes a plurality of gas sources connected in parallel.

[0015] According to an embodiment of the utility model, the gas purification system includes at least two of the above-mentioned gas purification devices, the two gas purification devices are redundant with each other, and one of them is connected to the above-mentioned gas source.

[0016] According to the gas purification device and gas purification system provided by the utility model, the cold trap body is installed on the cold head of the first refrigerator, and the cold head replaces the liquid nitrogen in the prior art as the cold source, which can not only reduce the volume of the device, but also prevent the leakage of liquid nitrogen and avoid replenishing the liquid nitrogen. The first branch of the pipeline mechanism connects the cold trap body in parallel with the circulation pipeline of the gas source, so that the working medium can be switched between the circulation pipeline and the cold trap body. The first branch in the cut-off state allows the working medium to pass through the circulation pipeline and isolates the cold trap body from the working medium, so that the impurities adsorbed by the cold trap body can be cleaned online through the desorption mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a three-dimensional diagram of a gas purification device according to an exemplary embodiment of the utility model;

[0018] Figure 2 yes Figure 1 A perspective view of the gas purification device is shown, showing the cold trap body;

[0019] Figure 3 yes Figure 1 The gas circuit diagram of the gas purification device shown;

[0020] Figure 4 yes Figure 1 A gas circuit diagram of another schematic embodiment of a gas purification device shown;

[0021] Figure 5 yes Figure 1 An enlarged partial view of the gas purification device shown, showing the adapter ring;

[0022] Figure 6is a module schematic diagram of a gas purification system according to an illustrative embodiment of the utility model; and

[0023] Figure 7 It is a module schematic diagram of a gas purification system according to another exemplary embodiment of the utility model, showing an embodiment with two gas purification devices.

[0024] In the drawings, the meanings of the reference numerals are as follows:

[0025] 1. Cold trap mechanism;

[0026] 11. Vacuum cover;

[0027] 12. Cold trap body;

[0028] 121, Part I;

[0029] 122, Part II;

[0030] 13. Intake pipe;

[0031] 14. Exhaust pipe;

[0032] 2. Connecting mechanism;

[0033] 21. First flange;

[0034] 22. Sleeve;

[0035] 23. Second flange;

[0036] 24. Adapter ring;

[0037] 3. Cold head;

[0038] 4. Circulation pipeline;

[0039] 5. Pipeline mechanism;

[0040] 51. First branch road;

[0041] 52. Second branch road;

[0042] 53. Third branch road;

[0043] 6. The first vacuum pump;

[0044] 7. Air extraction pipeline;

[0045] 8. Second vacuum pump;

[0046] 9. Gas source;

[0047] 91. First gas source;

[0048] 92. Second air source;

[0049] 93. The third gas source; and

[0050] 94. The fourth source of gas. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0052] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "include", "comprises", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0053] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0054] When using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted as the meaning of the expression generally understood by those skilled in the art. For example, "a system having at least one of A, B, and C" should include but not be limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc. When using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted as the meaning of the expression generally understood by those skilled in the art. For example, "a system having at least one of A, B, or C" should include but not be limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.

[0055] Based on different technical fields, the cold trap mechanism in the gas purification device can be configured under different temperature conditions.

[0056] For example, when adsorbing impurities during the liquefaction process of natural gas (mainly including methane), the operating temperature of the cold trap mechanism of the gas purification device can be maintained at -162°C (approximately 110 K) or below, so that at least a portion of the water, carbon dioxide and other heavy hydrocarbons in the natural gas are condensed before methane and thus removed.

[0057] For example, in the pharmaceutical field, in gas chromatography (GC) or gas chromatography-mass spectrometry (GC-MS) analysis, the operating temperature of the cold trap mechanism of the gas purification device can be maintained between -20°C and -80°C to condense a portion of the compounds in the organic solvent.

[0058] For another example, during the silicon wafer manufacturing process, the cold trap mechanism of the gas purification device can be maintained at -252.87°C (approximately 20K) to remove a portion of the hydrogen, or maintained at -34.04°C (approximately 239.11 K) to remove a portion of the chlorine.

[0059] For example, taking the dilution refrigerator as an example, the working fluid of the dilution refrigerator (mainly helium-3) will be mixed with some impurities during the circulation process, such as water vapor, oil vapor and gas molecules that are not easy to condense at room temperature (such as hydrogen, nitrogen and oxygen, etc.). These impurities will not participate in the main endothermic process (that is, helium-3 enters the dilution phase) during the circulation of the working fluid in the sealed circulation system (such as the circulation pipeline). Therefore, it will affect the performance and cooling capacity of the dilution refrigerator, resulting in the inability of the dilution refrigerator to cool down to the required extremely low temperature (such as the millikelvin level); even due to the condensation or solidification of impurities, the gas path will be blocked, making the dilution refrigerator unable to work normally.

[0060] Based on the above usage scenarios (it should be understood that the above usage scenarios are only schematic, and the gas purification device includes but is not limited to the above usage scenarios), at present, the cold trap mechanism of the gas purification device used is mainly set in the Dewar. When cleaning the cold trap body sealed in liquid nitrogen, it is necessary to release the sealing state of the Dewar (at this time, the liquid nitrogen in the Dewar will vaporize and leak until it is emptied. For this reason, this process cannot be carried out in a sealed indoor environment, and it will cause a large amount of liquid nitrogen consumption), and move the cold trap body out of the Dewar to the external environment. After the cold trap body is heated to room temperature, it is desorbed and cleaned; after cleaning, it needs to be reinstalled in the Dewar, and liquid nitrogen is replenished accordingly to cool it down again until it reaches a suitable adsorption temperature. For this reason, the above process is complicated to operate and takes a long time (up to several hours), and because the cold trap body needs to be dismantled, it is also impossible to desorb and clean the cold trap body online.

[0061] On this basis, how to provide a gas purification device and a gas purification system that occupies a small space and can be cleaned online has become a technical problem that needs to be solved urgently.

[0062] Figure 1 It is a stereoscopic diagram of a gas purification device according to an illustrative embodiment of the utility model. Figure 2 yes Figure 1 A perspective view of a gas purification device is shown, showing the cold trap body. Figure 3 yes Figure 1 The gas circuit diagram of the gas purification device is shown.

[0063] According to the gas purification device provided by the utility model, it includes a cold trap mechanism 1, a pipeline mechanism 5 and a desorption mechanism. The cold trap mechanism 1 includes a cold trap body 12 and a vacuum cover 11. The cold trap body 12 is installed on the cold head 3 of the first refrigerator, and forms heat conduction with the cold head 3, so that the cold head 3 cools down the temperature to a first temperature suitable for adsorbing impurities; the vacuum cover 11 is arranged on the outside of the cold trap body 12, and the vacuum cover 11 defines a vacuum chamber suitable for being extracted to a vacuum state, so that the cold trap body 12 is thermally isolated from the external environment. The pipeline mechanism 5 includes a first branch 51, which is suitable for setting the cold trap body 12 in parallel on the circulation pipeline 4 of the gas source 9 to be purified, and is configured to be selectively connected with the circulation pipeline 4. The desorption mechanism is configured to heat the cold trap body 12 to a second temperature suitable for desorbing impurities in response to the cut-off state of the first branch 51, and extract the impurities in the cold trap body 12.

[0064] To illustrate the gas purification device provided by the present invention, the following is an explanation of an implementation method in which the gas purification device is applied to adsorb impurities in the working fluid (mainly including helium 3) of a dilution refrigerator. This implementation method is exemplary and does not mean that the gas purification device provided by the present invention can only be used to adsorb impurities in the working fluid of a dilution refrigerator.

[0065] In the above-mentioned illustrative embodiment, the dilution refrigerator is a millikelvin-level refrigeration device that uses a mixture of helium 3 and helium 4 for a dilution refrigeration cycle. Under the temperature condition of 0.86K (the theoretical upper limit), helium 3 and helium 4 will separate into two phases, wherein the concentrated phase located in the upper layer mainly includes helium 3, and the dilution phase located in the lower layer is a mixture of helium 3 and helium 4. During the dilution refrigeration process, the pump group is suitable for extracting the helium 3 in the dilution phase to the room temperature gas circuit circulation and returning to the concentrated phase. Since the mixed liquid needs to maintain chemical potential equilibrium, the helium 3 atoms in the concentrated phase will enter the dilution phase and absorb heat in the process, so that the dilution refrigerator has a refrigeration effect.

[0066] In an illustrative embodiment, Figures 1 to 3 As shown, the gas purification device also includes a second vacuum pump 8. Specifically, the second vacuum pump 8 is connected to a joint (including but not limited to a standard threaded joint, such as a joint with a model of KN25) provided on the vacuum cover 11 through an exhaust pipe 7. Further, a sixth valve (i.e., Figure 3 Thus, when the cold trap is in the first mode of operation (eg, Figure 3 In the state of working medium flow direction indicated by the solid arrow shown in the figure), the vacuum chamber defined in the vacuum cover can be evacuated to a vacuum state by the second vacuum pump 8, so that the cold trap body 12 is thermally isolated from the external environment.

[0067] Figure 4 yes Figure 1 A gas circuit diagram of another schematic embodiment of a gas purification device is shown.

[0068] Reference Figure 4 , another exemplary embodiment is shown, in which the gas purification device is only equipped with one vacuum pump (ie, the first vacuum pump 6 ). Specifically, the exhaust pipeline 7 is connected to the air inlet end of the first vacuum pump 6 .

[0069] In such an embodiment, since the timing of evacuating the vacuum hood 11 and the timing of evacuating the cold trap body 12 for desorption are staggered (the timing of evacuating the vacuum hood 11 is often before the gas purification device is operated and earlier than the desorption and cleaning of the cold trap body 12), the vacuum extraction requirement can be met only by setting up the gas circuit, which not only saves a vacuum pump but also further reduces the volume of the gas purification device.

[0070] In an illustrative embodiment, Figure 1 and Figure 2 As shown, the cold trap body 12 includes but is not limited to a cylinder structure configured to be roughly cylindrical. In detail, an adsorption chamber is defined in the cold trap body 12, and the adsorption chamber is filled with an adsorption material, which is a porous structure and has a high specific surface area. For example, activated carbon, molecular sieves, copper mesh, activated alumina, silica gel, metal adsorbents and at least one other material suitable for adsorbing impurities (such as water vapor, oil vapor and gas molecules that are not easily condensed at room temperature) passing through the cold trap body 12 can be used.

[0071] In an illustrative embodiment, Figure 1 and Figure 2 As shown, the first refrigerator includes but is not limited to a pulse tube cryogenic refrigerator with a low power of 70K (Kelvin). In detail, the cold trap body 12 is directly mounted on the cold head 3 of the first refrigerator, and the cold head 3 as a cold source reduces the cold trap body 12 to a first temperature through heat conduction, and the first temperature includes but is not limited to 77K (Kelvin) or below. It should be understood that the embodiments of the utility model are not limited thereto.

[0072] For example, the first refrigerator may also be a GM refrigerator (ie, a Gifford-McMahon refrigerator based on the Joule-Thomson effect) or other refrigerators and / or mechanical cold heads suitable for cooling the cold trap body 12 to the first temperature or below.

[0073] In an illustrative embodiment, Figure 3 As shown, the cold trap body 12 is connected in series to the first branch 51. Furthermore, the first branch 51 also connects the cold trap body 12 in parallel to the circulation pipeline 4 of the gas source to be purified.

[0074] In an illustrative embodiment, Figure 3 As shown, the circulation pipeline 4 is provided with a first valve (i.e. Figure 3 Further, the first branch 51 is provided with a second valve at the air inlet and the air outlet of the cold trap body 12 (i.e., Figure 3 V2 as shown) and the third valve (i.e. Figure 3 V3 shown).

[0075] The first valve (V1), the second valve (V2) and the third valve (V3) are controlled in coordination. If the first valve (V1) is in the on state, the second valve (V2) and the third valve (V3) are in the off state; correspondingly, if the first valve (V1) is in the off state, the second valve (V2) and the third valve (V3) are in the on state. In this way, the gas purification device can be operated in the first mode (i.e., as shown in FIG. 1 ) for adsorbing impurities in the working medium (e.g., helium 3). Figure 3 The solid arrow direction shown in FIG. 1 ) and the second mode in which the working fluid is adsorbed without passing through the cold trap body 12 (i.e., as shown in FIG. 1 ). Figure 3 to switch between the directions of the dashed arrows shown).

[0076] When the gas purification device is in the second mode (i.e. Figure 3 In the state of the dotted arrow direction shown in the figure, the desorption mechanism participates in the work to clean the impurities in the cold trap body 12 online (even if the impurities are desorbed from the adsorption material) during the continuous operation of the gas source, so that the cold trap body 12 can be restored to the second temperature (such as room temperature) and desorb.

[0077] In such an embodiment, the cold trap body 12 is installed on the cold head 3 of the first refrigerator, and the cold head 3 replaces the liquid nitrogen in the prior art as the cold source, which can not only reduce the volume of the device, but also prevent the leakage of liquid nitrogen, thereby improving the safety of the device and avoiding the consumption of liquid nitrogen. The first branch 51 of the pipeline mechanism 5 connects the cold trap body 12 in parallel to the circulation pipeline 4 of the gas source, so that the working medium (such as helium 3) can be switched between the circulation pipeline 4 and the cold trap body 12. The first branch 51 in the cut-off state allows the working medium to pass through the circulation pipeline 4 and isolates the cold trap body 12 from the working medium, so that the impurities adsorbed by the cold trap body 12 are cleaned online through the desorption mechanism.

[0078] Furthermore, the cold trap body 12 uses the cold head 3 as a cold source. When the cold trap body 12 is cleaned, there is no need to dismantle the gas purification device, and the cold trap body 12 can be adjusted between the first temperature and the second temperature, thereby shortening the time required for cleaning the cold trap body 12 and improving the convenience of cleaning the cold trap body 12. In this process, although in the second mode, the working fluid (such as helium 3) does not pass through the cold trap body 12 for adsorption and impurity removal, and directly enters the gas source (such as a dilution refrigerator). However, the time for desorption and cleaning of the cold trap body 12 (such as about one hour) is negligible compared to the working time of the gas source (such as a dilution refrigerator) (in months, such as continuous operation for 1 month or more), and will not affect the performance and cooling capacity of the gas source (such as a dilution refrigerator). For this reason, the online cleaning of the cold trap body 12 can be achieved. It should be understood that the refrigerator to be purified in the utility model includes but is not limited to the use of a dilution refrigerator.

[0079] For example, the refrigerator to be purified may be any one of a compression refrigerator, an absorption refrigerator, a Stirling refrigerator, a pulse tube refrigerator, a magnetic refrigerator, and other low-temperature refrigerators. The above and following embodiments are merely examples of dilution refrigerators to schematically illustrate the gas purification device, and the gas purification device may also be applied to any other refrigerator that removes impurities from the working medium through a cold trap mechanism and to a gas source that is suitable for purification.

[0080] According to the embodiments of the present utility model, Figure 2 As shown, the cold trap mechanism 1 further includes an air inlet pipe 13 and an air outlet pipe 14, wherein the air inlet pipe 13 is used as the air inlet end of the cold trap body 12, and the air outlet pipe 14 is used as the air outlet end of the cold trap body 12. The air inlet pipe 13 and the air outlet pipe 14 are arranged side by side to form heat conduction.

[0081] In an illustrative embodiment, Figure 2 As shown, the air inlet pipe 13 and the air outlet pipe 14 of the cold trap mechanism 1 include but are not limited to being arranged on the upper part of the cold trap body 12. In detail, at least a portion of the air inlet pipe 13 and the air outlet pipe 14 (such as Figure 2 The middle part shown in the figure, i.e., the part roughly parallel to the cold trap body 12) is connected side by side (such as welding) so that the working medium can exchange heat with the low-temperature working medium discharged from the outlet pipe 14 during the process of entering the inlet pipe 13, so as to pre-cool the working medium before entering the cold trap body 12.

[0082] According to the embodiments of the present utility model, Figure 2 As shown, the cold trap body 12 includes a first portion 121 close to the cold head 3 and a second portion 122 away from the cold head 3. The first portion 121 and the second portion 122 are made of different materials, and the thermal conductivity of the first portion 121 is higher than that of the second portion 122.

[0083] According to the embodiments of the present utility model, Figure 2 As shown, an adsorption material is disposed in the cold trap body 12 , and the adsorption material is at least filled in the first portion 121 .

[0084] In an illustrative embodiment, Figure 2 As shown, the first portion 121 of the cold trap body 12 (such as Figure 2 The lower part shown in FIG. 1 is connected to the second part 122 of the cold trap body 12 (as shown in FIG. Figure 2 In detail, the first part 121 and the second part 122 are made of different materials, including but not limited to being made of one piece by welding, so that there is good sealing between the first part 121 and the second part 122, thereby preventing the working fluid from leaking from the cold trap body 12.

[0085] In a preferred embodiment, the first part 121 includes but is not limited to being made of copper. Furthermore, the second part 122 includes but is not limited to being made of stainless steel. In such an embodiment, copper has a better thermal conductivity than stainless steel. It is installed on the cold head 3 and can be quickly cooled to the first temperature under the action of the cold head 3. The second part 122 made of stainless steel and the pre-cooled air intake pipe 13 can form a relatively uniform temperature gradient when the working medium enters the cold trap body 12, thereby achieving step cooling to fully utilize the cold source.

[0086] In an illustrative embodiment, the adsorption material includes but is not limited to being filled in the first part 121. Further, the end of the inlet pipe 13 located in the cold trap body 12 is inserted into the bottom of the adsorption material, and the end of the outlet pipe 14 located in the cold trap body 12 is located in the second part 122, so that the impurities in the working fluid (such as helium 3) passing through the adsorption material are fully adsorbed by the adsorption material.

[0087] According to the embodiments of the present utility model, Figure 3 As shown, the desorption mechanism includes a heating component (not shown in the figure) and a first vacuum pump 6. The heating component is suitable for heating the cold trap body 12 to a second temperature (such as room temperature). The first vacuum pump 6 is connected to the cold trap body 12 and is suitable for extracting impurities desorbed from the cold trap body 12.

[0088] According to an embodiment of the present invention, the heating assembly is not shown in the figure, and is disposed in the cold head 3. The desorption mechanism further includes a temperature collection assembly (not shown) in communication with the heating assembly, and is suitable for collecting the temperature of the cold head 3 and / or the cold trap body 12.

[0089] In an illustrative embodiment, a heating component and / or a temperature collection component may be disposed in the cold head 3, wherein the heating component includes but is not limited to a resistance heater, a heating belt, a PTC (positive temperature coefficient) heater, a ceramic heater, a heat exchanger, and any other heating component suitable for heating the cold trap body 12 to a second temperature (such as room temperature); the temperature collection component includes but is not limited to a platinum resistor (such as PT100 or PT1000), a thermocouple, a nickel resistance temperature sensor (ie, NTC), a diode temperature sensor, and any other temperature collection component suitable for collecting the temperature of the cold trap body 12 under a first temperature (such as 77K). In detail, since the cold trap body 12 is assembled with the cold head 3, a good heat conduction is formed, and therefore, it can be regarded that the temperature of the cold trap body 12 is substantially the same as the temperature of the cold head 3. On this basis, the heating component and the temperature collection component are installed on the cold head 3, which can be regarded as heating the cold trap body 12 and collecting the temperature.

[0090] According to the embodiments of the present utility model, Figure 3 As shown, the pipeline mechanism 5 also includes a second branch 52 arranged between the cold trap body 12 and the circulation pipeline 4. The second branch 52 connects the cold trap body 12 and the circulation pipeline 4 in response to the cut-off state of the first branch 51, so that the working fluid remaining in the cold trap body 12 flows back to the circulation pipeline 4.

[0091] In an illustrative embodiment, Figure 3 As shown, the second branch 52 is arranged at the air inlet end of the cold trap body 12 (such as Figure 3 In detail, a fourth valve (i.e., Figure 3 V4 as shown), and the second branch 52 is maintained in a negative pressure state. The negative pressure state formed by the second branch 52 is mainly achieved by a pump arranged between the second branch 52 and the circulation pipeline 4. For example, a molecular pump (or other pumps, not shown in the figure) can be arranged between the second branch 52 and the circulation pipeline 4, and one end of the second branch 52 away from the fourth valve (i.e., V4) is arranged at the front end of the molecular pump (or other pumps, not shown in the figure), so that a negative pressure state is formed in the second branch 52 under the suction action of the molecular pump (or other pumps, not shown in the figure).

[0092] In an illustrative embodiment, Figure 3 As shown, the pipeline mechanism 5 also includes a third branch 53. In detail, the first vacuum pump 6 is arranged on the third branch 53. Further, a fifth valve (i.e., Figure 3 V5 shown).

[0093] In a preferred embodiment, in order to facilitate the control of the circulation pipeline and the branches of the pipeline mechanism 5, the above-mentioned valves and pumps can be coordinated and controlled through corresponding control terminals (such as PLC, i.e., programmable logic controller, host computer or other equipment). Figure 3 As shown in the gas circuit diagram, the first valve (i.e., V1), the second valve (i.e., V2), the fourth valve (i.e., V4), the fifth valve (i.e., V5) and the sixth valve (i.e., V6) can be controlled in a non-electrically closed manner, and the third valve (i.e., V3) can be controlled in a non-electrically opened manner.

[0094] In such an embodiment, when the gas purification device is in the second mode, the second valve (i.e., V2) and the third valve (i.e., V3) are closed, so that the first branch 52 is in a cut-off state, and the working medium circulates in the gas source through the circulation pipeline 4; at this time, the fourth valve (i.e., V4) is opened, and the working medium (such as helium 3) remaining in the cold trap body is refluxed to the circulation pipeline 4 (or the working medium source connected to the circulation pipeline 4) through the negative pressure in the second branch 52 to extract the working medium, and the fourth valve (i.e., V4) is closed after the gas pressure is lower than a preset value (including but not limited to 10 mbar), thereby preventing the waste of working medium; after the working medium is completely extracted, the fifth valve (i.e., V5) is opened and The cold trap body 12 is slowly raised to a second temperature (such as room temperature) by the heating component, and is stably maintained for a preset time (including but not limited to half an hour), and then the impurities desorbed from the adsorption material of the cold trap body 12 are extracted by the first vacuum pump 6 until the impurities are cleaned up; after the impurities are cleaned up, the fifth valve (i.e., V5) is closed, and the cold trap body 12 is cooled by the cold head 3 until the first temperature (such as 77K) is restored, and is stably maintained for a preset time (including but not limited to half an hour), and then the second valve (i.e., V2) and the third valve (i.e., V3) are opened, and the first valve (i.e., V1) is closed, so that the gas purification device returns to the first mode of adsorbing impurities in the working fluid.

[0095] Figure 5 yes Figure 1 An enlarged partial view of the gas purification device is shown, showing the adapter ring.

[0096] In an illustrative embodiment, Figure 1 and Figure 5As shown, the gas purification device also includes a connecting mechanism 2 arranged between the cold trap body 12 and the cold head 3. In detail, the connecting mechanism 2 includes a first flange 21 installed at the lower end of the cold trap body 12, a second flange 23 installed at the upper end of the cold head 3, and a sleeve located between the first flange 21 and the second flange 23. Further, the first flange 21, the second flange 23 and the sleeve 23 define a chamber connected to the vacuum chamber, so that they are all drawn to a vacuum state under the action of the second vacuum pump 8, thereby maintaining thermal isolation of the connection position between the cold trap body 12 and the cold head 3. Among them, the first flange 21 and / or the second flange 23 include but are not limited to vacuum caliper flanges.

[0097] In an illustrative embodiment, Figure 5 As shown, the connection mechanism 2 further includes an adapter ring 24. In detail, the cold trap body 12 and the cold head 3 are connected via the adapter ring 24. The adapter ring 24 includes but is not limited to being made of copper.

[0098] Figure 6 It is a module schematic diagram of a gas purification system according to an illustrative embodiment of the utility model.

[0099] Based on the same concept, the utility model also provides a gas purification system, such as Figure 6 As shown, it includes at least one gas source 9 to be purified, at least one gas purification device and a second vacuum pump 8. The first branch 51 of the gas purification device is connected in parallel with the circulation pipeline 4 of each gas source 9, and is configured to be selectively connected to the circulation pipeline 4. The second vacuum pump 8 is connected to the vacuum cover 11 of the gas purification device, and is suitable for extracting the vacuum chamber to a vacuum state. Among them, the gas purification device is configured to adsorb impurities in the working fluid in response to the conduction state of the first branch 51, and is configured to desorb impurities in the cold trap body 12 of the gas purification device in response to the truncation state of the first branch 51.

[0100] According to the embodiments of the present utility model, Figure 6 As shown, the gas purification system includes a plurality of gas sources 9 connected in parallel. The gas source 9 includes but is not limited to a dilution refrigerator using helium 3 as a working fluid and forming a heat exchange cycle, or a refrigeration device having a dilution refrigerator.

[0101] In an illustrative embodiment, Figure 6 As shown, the gas purification system includes but is not limited to four gas sources 9, namely Figure 6The first gas source 91, the second gas source 92, the third gas source 93 and the fourth gas source 94 are arranged in sequence from left to right. In detail, each gas source (i.e., the first gas source 91, the second gas source 92, the third gas source 93 and the fourth gas source 94 are all equipped with independent circulation pipelines 4) are connected in parallel. Furthermore, the gas inlet end and the gas outlet end of the working fluid of each gas source 9 are also respectively connected to a gas purification device. Among them, the gas source 9 includes but is not limited to a refrigerator, a pipeline connected to the refrigerator, a pump, a valve, a detection component (such as a pressure gauge, a flow meter, a thermometer and other metering devices suitable for collecting the state of the working fluid) and other components suitable for circulating the gas between the gas source and the external environment.

[0102] In such an implementation, a gas purification device can be used to clean (i.e., remove impurities) from multiple gas sources 9 that are close in space. Furthermore, in the initial operation stage of the gas source 9 (at this stage, there are many gas impurities entrained in the working fluid), it may be difficult to meet the adsorption requirements of a large number of impurities through the cold trap mechanism of a gas purification device at the same time. For this reason, multiple gas sources 9 can be configured with different start-up times to share the cold trap mechanism of the gas purification device among the multiple gas sources 9.

[0103] Figure 7 It is a module schematic diagram of a gas purification system according to another exemplary embodiment of the utility model, showing an embodiment with two gas purification devices.

[0104] According to the embodiments of the present utility model, Figure 7 As shown, the gas purification system includes at least two gas purification devices, the two gas purification devices are redundant with each other, and one of them is connected to the gas source 9.

[0105] In an illustrative embodiment, Figure 7 As shown, two independent gas purification devices can be configured in the gas purification system. In detail, the two gas purification devices can refer to Figure 7 The connection modes shown are respectively connected to a plurality of gas sources 9 in the gas purification system.

[0106] In such an embodiment, two gas purification devices can be connected to each gas source 9 in the gas purification system, so as to be redundant with each other, that is, when one gas purification device is in the first mode of adsorbing impurities, the other is in the second mode of waiting for operation or desorbing the adsorbed impurities. In this way, the gas purification system can be continuously operated without idle time when impurities cannot be adsorbed, and can be adapted to the use scenario where there are a large number of impurities in the gas source. Taking the use scenario of adsorbing impurities in the working fluid of a dilution refrigerator as an example, it can be applied to the initial operation state of the dilution refrigerator and / or the operation state where a large number of gas impurities are entrained due to leaks in the circulation pipeline.

[0107] It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only for reference to the drawings and are not intended to limit the scope of protection of the present invention. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted when they may cause confusion in the understanding of the present invention.

[0108] The embodiments of the present invention are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present invention is defined by the attached claims and their equivalents. Without departing from the scope of the present invention, a person skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A gas purification device, characterized in that: include: The cold trap mechanism (1) comprises: The cold trap body (12) is mounted on the cold head (3) of the first refrigerator and forms heat conduction with the cold head (3) so as to be cooled by the cold head (3) to a first temperature suitable for adsorbing impurities; A vacuum cover (11) is arranged outside the cold trap body (12), wherein a vacuum chamber suitable for being evacuated to a vacuum state is defined inside the vacuum cover (11), so that the cold trap body (12) is thermally isolated from the external environment; The pipeline mechanism (5) comprises: A first branch (51) is adapted to be arranged in parallel with the cold trap body (12) on a circulation pipeline (4) of a gas source to be purified, and is configured to selectively communicate with the circulation pipeline (4); The desorption mechanism is configured to heat the cold trap body (12) to a second temperature suitable for desorbing impurities in response to the cut-off state of the first branch (51), and to extract impurities from the cold trap body (12).

2. The purification device according to claim 1, characterized in that: The desorption mechanism comprises: a heating component, adapted to heat the cold trap body (12) to the second temperature; and The first vacuum pump (6) is connected to the cold trap body (12) and is suitable for extracting impurities desorbed from the cold trap body (12).

3. The purification device according to claim 2, characterized in that: The heating component is arranged in the cold head (3); The desorption mechanism also includes a temperature collection component that is communicatively connected to the heating component and is suitable for collecting the temperature of the cold head (3) and / or the cold trap body (12).

4. The purification device according to claim 1, characterized in that: The pipeline mechanism (5) further comprises a second branch (52) arranged between the cold trap body (12) and the circulation pipeline (4); the second branch (52) connects the cold trap body (12) and the circulation pipeline (4) in response to the cut-off state of the first branch (51), so as to allow the working fluid remaining in the cold trap body (12) to flow back to the circulation pipeline (4).

5. The purification device according to any one of claims 1 to 4, characterized in that: The cold trap mechanism (1) further comprises an air inlet pipe (13) and an air outlet pipe (14), wherein the air inlet pipe (13) serves as an air inlet end of the cold trap body (12), and the air outlet pipe (14) serves as an air outlet end of the cold trap body (12); Wherein, the air inlet pipe (13) and the air outlet pipe (14) are arranged side by side to form heat conduction.

6. The purification device according to any one of claims 1 to 4, characterized in that: The cold trap body (12) comprises a first portion (121) close to the cold head (3) and a second portion (122) far from the cold head (3); The first part (121) and the second part (122) are made of different materials, and the thermal conductivity of the first part (121) is higher than the thermal conductivity of the second part (122).

7. The purification device according to claim 6, characterized in that: An adsorption material is arranged in the cold trap body (12), and the adsorption material is at least filled in the first part (121).

8. A gas purification system, characterized in that: include: at least one gas source to be purified (9); At least one gas purification device according to any one of claims 1 to 7, wherein the first branch (51) of the gas purification device is connected in parallel with the circulation pipeline (4) of each of the gas sources (9), and is configured to selectively communicate with the circulation pipeline (4); and A second vacuum pump (8) is connected to the vacuum cover (11) of the gas purification device and is suitable for evacuating the vacuum chamber to a vacuum state; The gas purification device is configured to adsorb impurities in the working fluid in response to the conduction state of the first branch (51), and is configured to desorb impurities in the cold trap body (12) of the gas purification device in response to the cut-off state of the first branch (51).

9. The gas purification system according to claim 8, characterized in that: It comprises a plurality of gas sources (9) connected in parallel.

10. The gas purification system according to claim 8, characterized in that: It comprises at least two gas purification devices, the two gas purification devices are redundant with each other, and one of them is connected to the gas source (9).

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