Gas detection equipment

Abstract

The utility model discloses gas detection equipment which is applied to detection of radioactive gas containing target nuclides and comprises an adsorption assembly, a heating assembly, a cleaning assembly and a preheating assembly, and the adsorption assembly can adsorb the target nuclides in the radioactive gas; the heating assembly is used for heating the adsorption assembly and enabling the adsorption assembly to release the adsorbed target nuclide; the cleaning assembly is communicated with the adsorption assembly and is used for providing purging gas which does not react with the radioactive gas for the adsorption assembly; the preheating assembly is arranged between the cleaning assembly and the adsorption assembly and used for heating the purging gas. The gas detection equipment can improve the cleaning effect and cleaning efficiency of the cleaning assembly through the preheating assembly. The device is applied to the field of radioactive gas treatment.

Description

Technical Field

[0001] This utility model relates to the field of radioactive gas processing, and in particular to a gas detection device. Background Technology

[0002] The excessive consumption of global resources has led to a year-on-year increase in energy demand. Traditional fossil fuels can no longer meet people's needs for resources, nor can they meet the requirements of sustainable social development and ecological protection. Against this backdrop, nuclear technology has developed rapidly, and nuclear energy has gradually become a major source of new-generation energy, widely used in my country's national defense construction, power generation, and other fields. During nuclear power production, radioactive waste gases are generated. For industries that generate waste gases during production, there are usually corresponding gas emission standards to ensure that the emissions do not pollute the environment and achieve sustainable development. Therefore, airborne radioactive effluents from nuclear power production must be purified before being released into the atmosphere through chimneys; and the emitted airborne radioactive effluents need to be monitored, with measurements including total emissions, emission concentrations, and the content of major nuclides. Currently, the activity concentrations of airborne radioactive effluents (such as Kr and Rn) from nuclear power plants are roughly equivalent to the activity concentration levels in the air, below the detection limit of gamma spectroscopy analysis methods. This leads to inaccurate estimates of airborne radioactive effluents emitted by nuclear power plants, thus affecting the accuracy of the environmental impact assessment results of nuclear power plants. To solve this problem, it is usually necessary to enrich and separate trace amounts of radioactive gas so that it can reach the instrument's minimum detection limit, thereby enabling accurate measurement of airborne radioactive effluents.

[0003] Adsorption separation technology is widely used in gas separation due to its advantages such as energy efficiency, simple separation process, and low energy consumption. The core of adsorption separation technology lies in the selection of adsorbents. Commonly used adsorbent materials include silica gel, activated carbon, zeolite molecular sieves, metal-organic frameworks (MOFs), and non-metallic organic frameworks (COFs). The use of new adsorbent materials makes the application prospects of adsorption separation technology in the enrichment and separation of trace radioactive gases even broader.

[0004] In existing technologies, adsorbent materials are typically used to adsorb radionuclides to achieve enrichment. The radionuclides are then released from the adsorbent material into a detection device for content measurement. Furthermore, the adsorbent material can be reused after release, saving costs. However, during the release process, the adsorbent material is usually heated directly, and then purged with room-temperature gas to remove the radionuclides. When the purge gas comes into contact with the heated adsorbent material, it can easily lower the material's temperature, reducing the release efficiency and preventing the material from releasing all radionuclides, thus affecting the accuracy of radionuclide detection. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a gas detection device that can improve detection efficiency and accuracy.

[0006] The gas detection device according to an embodiment of the present invention is used for detecting radioactive gases containing a target nuclide, including:

[0007] The adsorption component is capable of adsorbing the target nuclide in the radioactive gas;

[0008] A heating component is used to heat the adsorption component and cause the adsorption component to release the adsorbed target nuclide;

[0009] A cleaning component, connected to the adsorption component, is used to provide the adsorption component with a purge gas that does not react with the radioactive gas;

[0010] A preheating component, located between the cleaning component and the adsorption component, is used to heat the purge gas.

[0011] The gas detection device according to the embodiments of the present invention has at least the following beneficial effects: the preheating component heats the purging gas delivered by the cleaning component, the high temperature purging gas has less impact on the temperature of the heated adsorption component, the purging component can more efficiently purge the target nuclides in the adsorption component, improve the release efficiency of the target nuclides in the adsorption component, and can completely release all target nuclides in the adsorption component, thereby improving the detection accuracy of the target nuclides.

[0012] According to some embodiments of the present invention, the preheating assembly includes a preheating cavity for preheating and a guide portion disposed within the preheating cavity. The guide portion is used to change the direction of the purge gas to increase the movement path of the purge gas within the preheating cavity.

[0013] According to some embodiments of the present invention, the preheating cavity is defined by the guide portion as a serpentine flow channel for conveying the purging gas.

[0014] According to some embodiments of the present invention, the adsorption component includes a shell and a porous adsorption element disposed within the shell. The shell has a first communicating position and a second communicating position. The shell is connected to the cleaning component at the first communicating position and to the outside or a collection cavity at the second communicating position. The porous adsorption element is located between the first communicating position and the second communicating position.

[0015] or,

[0016] The adsorption assembly includes a shell and a separation membrane. The shell defines a first cavity and a second cavity. The first cavity is connected to the cleaning assembly, and the second cavity is connected to the outside or a collection cavity. The separation membrane is disposed between the first cavity and the second cavity and connects the first cavity and the second cavity.

[0017] According to some embodiments of the present invention, the adsorption assembly includes the outer shell and the separation membrane, and the pressure in the second cavity is less than the pressure in the first cavity.

[0018] According to some embodiments of the present invention, the adsorption assembly includes the outer shell, the porous adsorption element, the first vacuum flange and the second vacuum flange, wherein the first vacuum flange is disposed at the first communication position and the second vacuum flange is disposed at the second communication position.

[0019] According to some embodiments of the present invention, the gas detection device further includes an exhaust gas treatment component, wherein the cleaning component, the adsorption component and the exhaust gas treatment component are connected in sequence, and the exhaust gas treatment component is used to collect the target nuclide or discharge the target nuclide to the outside world;

[0020] And / or,

[0021] The gas detection device further includes a detection component, wherein the cleaning component, the adsorption component, and the detection component are connected in sequence, and the detection component is used to detect the target nuclide in the purge gas.

[0022] According to some embodiments of the present invention, the gas detection device includes the exhaust gas treatment component, the detection component, and a first control valve group, wherein the first control valve group is used to switch the on / off state between the adsorption component and the exhaust gas treatment component, and between the adsorption component and the detection component.

[0023] According to some embodiments of the present invention, the gas detection device further includes:

[0024] A gas delivery assembly, connected to the adsorption assembly, is used to supply the radioactive gas to the adsorption assembly;

[0025] The second control valve group is used to switch the on / off state between the adsorption component and the gas delivery component, and between the adsorption component and the cleaning component;

[0026] The second control valve group is configured such that: when the adsorption component adsorbs the target nuclide, the adsorption component is connected to the gas delivery component and disconnected from the cleaning component; when the adsorption component releases the target nuclide, the adsorption component is disconnected from the gas delivery component and connected to the cleaning component, the heating component heats the adsorption component, and the preheating component preheats the purge gas.

[0027] According to some embodiments of the present invention, the gas detection device further includes a detection component, wherein the gas delivery component, the adsorption component, and the detection component are connected in sequence, and the detection component is used to detect the target nuclide in the radioactive gas.

[0028] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0030] Figure 1 This is a schematic diagram of the structure of a gas detection device using a porous adsorption element in an embodiment of the present invention.

[0031] Figure 2 This is a schematic diagram of the structure of the adsorption component of a gas detection device according to an embodiment of the present invention, in which a separation membrane is used.

[0032] Figure 3 This is a schematic diagram of the structure of the preheating component of a gas detection device according to an embodiment of the present invention;

[0033] Figure 4 (a) Isotherm of Kr adsorption at room temperature on ZIF-8 carbonized material; (b) Isotherm of Xe adsorption at room temperature on ZIF-8 carbonized material.

[0034] Icon labels:

[0035] Adsorption assembly 100; outer shell 110; first chamber 111; second chamber 112; porous adsorption element 120; separation membrane 130; first vacuum flange 140; second vacuum flange 150; back pressure valve 160;

[0036] Heating component 200;

[0037] Cleaning component 300;

[0038] Preheating component 400; preheating cavity 410; guide section 420;

[0039] Exhaust gas treatment assembly 500; cold trap 510; collection chamber 520; exhaust pipe 530;

[0040] Detection component 600;

[0041] First control valve assembly 700; First valve 710; Second valve 720;

[0042] Gas delivery assembly 800;

[0043] Second control valve group 900; third valve 910; second valve 920. Detailed Implementation

[0044] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0045] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0046] In the description of this utility model, "several" refers to one or more, and "multiple" refers to two or more. The use of "first" and "second" is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, the number of indicated technical features, or the sequential relationship between indicated technical features.

[0047] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0048] Reference Figures 1 to 3 As shown in the figure, this utility model embodiment proposes a gas detection device for detecting radioactive gases containing target nuclides, including: an adsorption component 100, a heating component 200, a cleaning component 300, and a preheating component 400, wherein the cleaning component 300, the preheating component 400, and the adsorption component 100 are connected in sequence, and the heating component 200 is directly connected to the adsorption component 100 or disposed within the adsorption component 100.

[0049] It should be noted that radioactive gas refers to gas containing radioactive nuclides, which are atoms that emit radioactivity. The target nuclide is one or more radioactive nuclides within the radioactive gas.

[0050] In this embodiment, the adsorption component 100 can adsorb the target nuclide in the radioactive gas. Specifically, the adsorption component 100 has a porous material inside. The porous material has a highly ordered network structure with a large specific surface area, providing suitable adsorption and storage space, which enhances the adsorption capacity of the porous material for nuclide molecules. Furthermore, the porous material can selectively adsorb and store the desired nuclide, thus separating the nuclide from other molecules. In other words, the pores of the porous material can just accommodate the target nuclide. When the radioactive gas passes through the porous material of the adsorption component 100, the target nuclide is embedded in the pores of the porous material, while the remaining gas passes through the porous material, thereby realizing the extraction of the target nuclide from the radioactive gas.

[0051] After the adsorption component 100 adsorbs the target nuclide, the heating component 200 heats the adsorption component 100 and causes it to release the adsorbed target nuclide. Specifically, the adsorption component 100 embeds the target nuclide in its pores. When the heating component 200 heats the target nuclide, the porous material expands due to heat, further increasing the pore size. The target nuclide can no longer be embedded in the pores, resulting in its de-embedding and separation from the porous material. In other words, under the heating action of the heating component 200, the adsorption component 100 will release the adsorbed target nuclide.

[0052] After the adsorption component 100 is heated by the heating component 200 and the target nuclide is released, the target nuclide concentrates within the adsorption component 100 or within the porous material of the adsorption component 100. To transfer the target nuclide within the adsorption component 100, a cleaning component 300 is connected to the adsorption component 100 to provide a purge gas that does not react with the radioactive gas. The purge gas transfers the target nuclide within the adsorption component 100 to other locations. The adsorption component 100 is then cleaned by the cleaning component 300, allowing it to be reused for a new round of target nuclide testing. The types of target nuclides can be the same or different. The purge gas is an inert gas or other gas that does not react with the radioactive gas.

[0053] During the process of purging the target nuclide in the adsorption component 100 with purge gas, the purge gas is generally at room temperature. The porous material in the adsorption component 100 reaches a higher temperature after heating. When the room-temperature purge gas comes into contact with the high-temperature porous material, the temperature difference causes the porous material to cool and the pores to shrink again. This leads to some of the released target nuclide being re-embedded in the porous material, affecting the complete release of the target nuclide by the adsorption component 100. By placing the preheating component 400 between the cleaning component 300 and the adsorption component 100 to heat the purge gas, the temperature difference between the purge gas and the porous material in the adsorption component 100 is reduced. The temperature of the purge gas becomes close to, equal to, or exceeds the temperature of the porous material in the adsorption component 100 after heating, making it less likely for target nuclides to remain in the adsorption component 100. This allows the adsorption component 100 to completely release the target nuclide, resulting in better cleaning performance. Furthermore, when the adsorption component 100 completely releases all target nuclides, the subsequent detection accuracy of the target nuclides is higher. Meanwhile, the preheating component 400 heats the purge gas delivered by the cleaning component 300. The high-temperature purge gas also helps to accelerate the release of the target nuclide in the adsorption component 100, improve cleaning efficiency, and shorten cleaning time.

[0054] Reference Figure 3 As shown, in some embodiments of the present invention, the preheating assembly 400 includes a preheating cavity 410 for preheating and a guide portion 420 disposed within the preheating cavity 410. The guide portion 420 is used to change the direction of the purge gas to increase the movement path of the purge gas within the preheating cavity 410.

[0055] It is understandable that by increasing the movement path of the purge gas within the preheating chamber 410 through the guide section 420, the purge gas passes through a larger area of ​​the preheating chamber 410, allowing the purge gas to fully exchange heat with the preheating chamber 410, thus enabling the purge gas to absorb more heat and making the temperature of the purge gas basically the same as the temperature of the adsorption component 100 after heating.

[0056] Reference Figure 3 As shown, in some specific embodiments of this utility model, the preheating cavity 410 is defined by the guide portion 420 as a serpentine flow channel for conveying the purging gas.

[0057] In this embodiment, the preheating cavity 410 includes a first sidewall and a second sidewall facing each other. The guide portion 420 includes a first guide plate and a second guide plate. The first guide plate is disposed on the first sidewall and extends toward the second sidewall, and the second guide plate is disposed on the second sidewall and extends toward the first sidewall. The first guide plate and the second guide plate are alternately distributed along the purging direction, so that a serpentine flow channel is formed inside the preheating cavity 410. The purging gas increases its movement path inside the preheating cavity 410 through the serpentine flow channel, thereby improving the heat exchange effect between the purging gas and the preheating cavity 410, so that the purging gas can be fully heated and the temperature is uniform.

[0058] In another embodiment, the preheating cavity 410 may be defined by a guide portion 420 to form a spiral flow channel, wherein the guide portion 420 may be a spiral tube.

[0059] In addition, a mass flow controller (MFC) is provided between the cleaning component 300 and the adsorption component 100 to control the flow rate of the purge gas input to the cleaning component 300.

[0060] Reference Figure 1 As shown, in some specific embodiments of this utility model, the adsorption component 100 includes a housing 110 and a porous adsorption element 120 disposed within the housing 110. The housing 110 has a first connecting position and a second connecting position. The housing 110 is connected to the cleaning component 300 at the first connecting position and connected to the outside or the collection cavity 520 at the second connecting position. The porous adsorption element 120 is located between the first connecting position and the second connecting position.

[0061] The outer shell 110 is made of stainless steel, and its specific shape and size can be selected as needed. The porous adsorbent 120 includes granular materials and / or powdered materials such as metal-organic framework (MOF), non-metal-organic framework (COF), zeolite, molecular sieve, and activated carbon derivatives. In this embodiment, the outer shell 110 is a hollow cylinder. Granular or powdered materials are sequentially filled into the outer shell 110 along the axial direction of the cylinder to form the porous adsorbent 120. The outer shell 110 has a first connecting position and a second connecting position at both ends along the axial direction of the cylinder, respectively. Radioactive gas will pass through the porous adsorbent 120 along the axial direction of the cylinder and fully contact the porous adsorbent 120, so that the target nuclide is embedded in the pores of the porous adsorbent 120.

[0062] Reference Figure 2As shown, in some specific embodiments of this utility model, the adsorption component 100 includes a shell 110 and a separation membrane 130. The shell 110 defines a first cavity 111 and a second cavity 112. The first cavity 111 is connected to the cleaning component 300, and the second cavity 112 is connected to the outside or the collection cavity 520. The separation membrane 130 is disposed between the first cavity 111 and the second cavity 112 and connects the first cavity 111 and the second cavity 112.

[0063] The outer shell 110 is also made of stainless steel, and its specific shape and size can be selected as needed. The separation membrane 130 is formed into a membrane shape from materials such as MOF and COF. In this embodiment, the outer shell 110 is also hollow cylindrical. The separation membrane 130 is located in the middle of the hollow cylinder along its axial direction, dividing the hollow cylinder into a first cavity 111 and a second cavity 112 that are substantially the same. Of course, the position of the separation membrane 130 can also be arranged as needed. For example, it can be located at one-third of the axial direction of the hollow cylinder, dividing the hollow cylinder into a first cavity 111 with one-third the size and a second cavity 112 with two-thirds the size, or a second cavity 112 with one-third the size and a first cavity 111 with two-thirds the size.

[0064] In addition, the heating component 200 heats the porous adsorption material. Specifically, it can heat the outer shell 110 to heat the porous adsorption element 120 or the separation membrane 130 at intervals, or the heating part of the heating component 200 is located inside the outer shell 110 to directly heat the porous adsorption element 120 or the separation membrane 130.

[0065] Reference Figure 2 As shown, in some specific embodiments of this utility model, the adsorption component 100 includes a shell 110 and a separation membrane 130, and the pressure in the second cavity 112 is less than the pressure in the first cavity 111.

[0066] It is worth understanding that by controlling the pressure in the second cavity 112 to be lower than the pressure in the first cavity 111, the radioactive gas in the first cavity 111 continuously moves toward the second cavity 112, and the target nuclide continuously embeds into the separation membrane 130, thereby improving the embedding efficiency of the target nuclide.

[0067] In this embodiment, the radioactive gas detection device further includes a back pressure valve 160, which is disposed between the adsorption component 100 and the monitoring component. The back pressure valve 160 is configured to adjust the pressure in the second chamber 112 to be lower than the pressure in the first chamber 111 when the pressure in the second chamber 112 is a preset pressure. Specifically, after radioactive gas is introduced for a period of time, both the first chamber 111 and the second chamber 112 are filled with radioactive gas. The pressure between the first chamber 111 and the second chamber 112 is basically the same and continues to increase with the introduction of gas. However, the fact that the pressures in the first chamber 111 and the second chamber 112 are basically the same leads to a decrease in the efficiency of the target nuclide embedding into the separation membrane 130. Therefore, when the pressure in the second cavity 112 increases to the preset pressure, the preset pressure is greater than the external pressure, causing the back pressure valve 160 to open under the action of the pressure difference. The radioactive gas in the second cavity 112 will be discharged, which at the same time causes the pressure in the second cavity 112 to decrease and become lower than the pressure in the first cavity 111, thereby improving the efficiency of the target nuclide embedding separation membrane 130.

[0068] Reference Figure 1 As shown, in some specific embodiments of this utility model, the adsorption assembly 100 includes a shell 110, a porous adsorption element 120, a first vacuum flange 140 and a second vacuum flange 150, the first vacuum flange 140 being disposed at a first communication position and the second vacuum flange 150 being disposed at a second communication position.

[0069] It is worth understanding that the outer casing 110 is connected to other pipes through the first vacuum flange 140 at the first connection position; the outer casing 110 is connected to other pipes through the second vacuum flange 150 at the second connection position. Only the first vacuum flange 140 and the second vacuum flange 150 need to be removed to directly remove the adsorption component 100 from the overall pipe, which makes it easier to disassemble the adsorption component 100 and use it.

[0070] In this embodiment, both the first vacuum flange 140 and the second vacuum flange 150 are KF flanges and are connected by clamps, making the installation and disassembly of the adsorption assembly 100 more convenient.

[0071] Reference Figure 1 and Figure 2 As shown, in some specific embodiments of this utility model, the gas detection device further includes an exhaust gas treatment component 500, a cleaning component 300, an adsorption component 100 and the exhaust gas treatment component 500 connected in sequence, and the exhaust gas treatment component 500 is used to collect target nuclides or discharge target nuclides to the outside world.

[0072] It is understandable that when the target nuclide is harmless, it can be directly discharged into the air; when the target nuclide is harmful, the exhaust gas treatment unit 500 will collect the target nuclide to prevent it from entering the air and affecting the health of workers, while reducing environmental pollution.

[0073] In this embodiment, when the exhaust gas treatment component 500 collects the target nuclide, the exhaust gas treatment component 500 includes a cold trap 510 and a collection chamber 520. Liquid nitrogen is injected into the cold trap 510, and the collection chamber 520 is placed in liquid nitrogen, which lowers the temperature of the collection chamber 520. The adsorption component 100 is directly connected to the collection chamber 520. When the target nuclide moves into the collection chamber 520, the target nuclide will remain in the collection chamber 520, thus completing the collection of the target nuclide.

[0074] In this embodiment, when the exhaust gas treatment component 500 discharges the target nuclide into the air, the exhaust gas treatment component 500 includes an exhaust pipe 530 and a mass flow controller (MFC) disposed in the exhaust pipe 530, and the gas flow rate is detected and controlled by the mass flow controller.

[0075] The venting pipe 530 and the collection chamber 520 can be connected to the adsorption component 100 through a two-position three-way valve, which enables the gas detection equipment to be applicable to a variety of target nuclides, making it more widely applicable and easier to use.

[0076] Reference Figure 1 and Figure 2 As shown, in some specific embodiments of this utility model, the gas detection device further includes a detection component 600, a cleaning component 300, an adsorption component 100 and the detection component 600 connected in sequence, and the detection component 600 is used to detect the target nuclide in the purge gas.

[0077] In this embodiment, the detection component 600 is a gas chromatograph or a gas chromatography-mass spectrometry system. The detection component 600 is connected to the cleaning component 300 and the adsorption component 100. During the continuous purging of the target nuclide with purge gas, the detection component 600 can continuously detect whether the purge gas contains the target nuclide. When the detection component 600 detects that the purge gas does not contain the target nuclide, or when the purge gas does not contain the target nuclide for a certain period of time, it is considered that the target nuclide in the adsorption component 100 has been completely desorbed. At this time, the adsorption component 100 can start the next round of target nuclide adsorption, detection, and regeneration. The detection component 600 can accurately detect the time when the target nuclide is completely released from the adsorption component 100, improving the utilization efficiency of the adsorption component 100.

[0078] In another implementation, the adsorption component 100 may be purged by the cleaning component 300 for a preset time. At the end of the purging time, the adsorption component 100 is considered to have completely released the target nuclide. The preset time can be set by the detection component 600 detecting the time it takes for the adsorption component 100 to completely release the target nuclide. To meet the requirement of complete release of the target nuclide by the adsorption component 100, the preset time needs to be slightly longer than the time detected by the detection component 600.

[0079] Reference Figure 1 and Figure 2 As shown, in some specific embodiments of this utility model, the gas detection device includes an exhaust gas treatment component 500, a detection component 600, and a first control valve group 700. The first control valve group 700 is used to switch the on / off state between the adsorption component 100 and the exhaust gas treatment component 500, and between the adsorption component 100 and the detection component 600.

[0080] It is worth understanding that both the exhaust gas treatment component 500 and the detection component 600 are connected to the adsorption component 100. The first control valve group 700 switches the adsorption component 100 on and off with the exhaust gas treatment component 500 or the detection component 600, making the switching of the exhaust gas treatment component 500 and the detection component 600 more convenient and facilitating the implementation of different functions to process multiple target nuclides, making it more convenient to use.

[0081] In this embodiment, the first control valve group 700 is a two-position three-way valve. The adsorption component 100, the detection component 600, and the exhaust gas treatment component 500 are all connected to the two-position three-way valve, and the two-position three-way valve controls the connection and disconnection between the adsorption component 100 and the exhaust gas treatment component 500, as well as between the adsorption component 100 and the detection component 600.

[0082] In another embodiment, the first control valve group 700 further includes a first valve 710 and a second valve 720. The first valve 710 is located between the adsorption component 100 and the exhaust gas treatment component 500 to control the opening and closing of the adsorption component 100 and the exhaust gas treatment component 500. The second valve 720 is located between the adsorption component 100 and the detection component 600 to control the opening and closing of the adsorption component 100 and the detection component 600.

[0083] Reference Figure 1 and Figure 2 As shown, in some specific embodiments of this utility model, the gas detection device further includes: a gas delivery assembly 800 and a second control valve assembly 900.

[0084] In this embodiment, the gas delivery assembly 800 is connected to the adsorption assembly 100 and is used to supply radioactive gas to the adsorption assembly 100, enabling the adsorption assembly 100 to adsorb the target nuclide in the radioactive gas. Specifically, the gas delivery assembly 800 includes a delivery source, a delivery pipeline, and a mass flow controller disposed on the delivery pipeline. The mass flow controller is used to control the speed at which the delivery source delivers the radioactive gas and to count the total amount of radioactive gas delivered. The delivery source can be a flow channel that is emitting radioactive gas or a storage device containing radioactive gas.

[0085] The second control valve group 900 is used to switch the connection and disconnection between the adsorption component 100 and the gas delivery component 800, and between the adsorption component 100 and the cleaning component 300. The second control valve group 900 is configured such that: when the adsorption component 100 adsorbs the target nuclide, the adsorption component 100 is connected to the gas delivery component 800 and disconnected from the cleaning component 300; when the adsorption component 100 releases the target nuclide, the adsorption component 100 is disconnected from the gas delivery component 800 and connected to the cleaning component 300, the heating component 200 heats the adsorption component 100, and the preheating component 400 preheats the purge gas.

[0086] The second control valve group 900 is a two-position three-way valve, or the second control valve group 900 includes a third valve 910 and a fourth valve 920, with the third valve 910 located between the adsorption component 100 and the cleaning component 300, and the fourth valve 920 located between the adsorption component 100 and the gas delivery component 800.

[0087] It is worth understanding that by controlling the second control valve group 900, the gas detection equipment can sequentially complete the adsorption of the target nuclide by the adsorption component 100 and the release of the target nuclide by the adsorption component 100. This enables the gas detection equipment to perform cyclic detection of the target nuclide through the same adsorption component 100, thereby achieving automated detection and higher detection efficiency.

[0088] Reference Figure 1 and Figure 2 As shown, in some specific embodiments of this utility model, the gas detection device further includes a detection component 600, a gas delivery component 800, an adsorption component 100 and a detection component 600 connected in sequence, and the detection component 600 is used to detect the target nuclide in the radioactive gas.

[0089] It is understandable that when the detection component 600 is connected to the gas delivery component 800 and the adsorption component 100, it is used to detect whether the radioactive gas passing through the adsorption component 100 contains the target nuclide. When the detection component 600 detects the target nuclide in the radioactive gas passing through the adsorption component 100 and the content of the target nuclide is stable and no longer changes, the adsorption component 100 has been fully adsorbed with the target nuclide and adsorption can be stopped. Subsequent target nuclide purging can then be performed.

[0090] In addition, in order to enable the adsorption component 100 to better adsorb the target nuclide, before the gas delivery component 800 delivers the radioactive gas, the cleaning component 300 is connected to the adsorption component 100 through the second control valve group 900, so that the purge gas activates the adsorption component 100 and improves the adsorption effect of the adsorption component 100 on the target nuclide.

[0091] For ease of understanding, a specific embodiment is described below as an example. The following content does not constitute a specific limitation on the utility model.

[0092] In this embodiment, ZIF-8 carbonized material was used as the adsorbent, with Kr and Xe as the target nuclides and He as the purge gas. Cyclic adsorption and desorption experiments were conducted on it. After 1, 5, and 10 cycles of adsorption and desorption, the adsorption performance of the material was tested and compared. The specific operation is as follows:

[0093] The adsorption assembly 100 includes a housing 110 and a porous adsorption element 120. The porous adsorption element 120 is made of carbonized ZIF-8 material. The porous adsorption element 120 is directly filled into the housing 110 and is connected to the cleaning assembly 300 and the gas delivery assembly 800 (gas chromatograph) through the second control valve group 900 (two-position three-way valve). It is also connected to the detection assembly 600 and the exhaust gas treatment assembly 500 through the first control valve group 700 (two-position three-way valve).

[0094] Activation: Adjust the second control valve group 900, connect the cleaning component 300 to the adsorption component 100, adjust the first control valve group 700, connect the detection component 600 to the adsorption component 100, and the cleaning component 300 delivers purge gas through the adsorption component 100 and into the detection component 600. The adsorption component 100 is heated to 80~100℃, and at the same time, the cleaning component 300 is purged with purge gas for 1~2 hours. The purge gas flow rate is 50~100 sccm. When there is no absorption peak of impurity gas in the detection component 600 (gas chromatograph), the adsorption component 100 stops heating. After the adsorption component 100 cools to room temperature, the adsorption test begins.

[0095] Adsorption: Adjust the second control valve group 900, connect the gas delivery component 800 to the adsorption component 100, and the gas delivery component 800 delivers the radioactive gas carrying the target nuclide through the adsorption component 100. The flow rate of the radioactive gas is 2~10 sccm. The detection component 600 detects the radioactive gas passing through the adsorption component 100. When the detection component 600 (gas chromatograph) detects that the absorption peak area of ​​the gas no longer changes, the adsorption component 100 has completed adsorption.

[0096] Desorption: Adjust the second control valve group 900, connect the cleaning component 300 to the adsorption component 100, and simultaneously heat the adsorption component 100 at a temperature of 80~100℃. The preheating component 400 also heats the adsorption component 100 at a temperature of 80~100℃. Then, the cleaning component 300 delivers a purge gas, such as He gas. When the detection component 600 (gas chromatograph) detects no absorption peak of impurity gas, the heating component 200 and the preheating component 400 stop heating. Once the adsorption component 100 cools to room temperature, a new cycle of adsorption and desorption can be repeated.

[0097] In summary, after 1, 5, and 10 cycles, the carbonized ZIF-8 material in adsorption module 100 was removed, and the Kr and Xe adsorption performance of the material was tested and compared. Specific data are as follows: Figure 4 As shown, Figure 4 From left to right, the images show the first, fifth, and tenth adsorption curves. The Kr adsorption capacity of the material is approximately 25 mL / g, and the Xe adsorption capacity is approximately 75 mL / g. Even after 10 adsorption-desorption cycles, the adsorption performance of the material remains unchanged. The data shows that the device has a significant self-cleaning effect, effectively cleaning the internal pores of the material without leaving any impurity gases or causing any damage to the material.

[0098] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A gas detection device for detecting radioactive gases containing a target nuclide, characterized in that, include: The adsorption component is capable of adsorbing the target nuclide in the radioactive gas; A heating component is used to heat the adsorption component and cause the adsorption component to release the adsorbed target nuclide; A cleaning component, connected to the adsorption component, is used to provide the adsorption component with a purge gas that does not react with the radioactive gas; A preheating component, located between the cleaning component and the adsorption component, is used to heat the purge gas.

2. The gas detection device according to claim 1, characterized in that: The preheating assembly includes a preheating chamber for preheating and a guide portion disposed within the preheating chamber. The guide portion is used to change the direction of the purge gas to increase the movement path of the purge gas within the preheating chamber.

3. The gas detection device according to claim 2, characterized in that: The preheating chamber is defined by the guide portion as a serpentine flow path for conveying the purging gas.

4. The gas detection device according to claim 1, characterized in that: The adsorption assembly includes a shell and a porous adsorption element disposed within the shell. The shell has a first connecting position and a second connecting position. The shell is connected to the cleaning assembly at the first connecting position and connected to the outside or a collection cavity at the second connecting position. The porous adsorption element is located between the first connecting position and the second connecting position. or, The adsorption assembly includes a shell and a separation membrane. The shell defines a first cavity and a second cavity. The first cavity is connected to the cleaning assembly, and the second cavity is connected to the outside or a collection cavity. The separation membrane is disposed between the first cavity and the second cavity and connects the first cavity and the second cavity.

5. The gas detection device according to claim 4, characterized in that: The adsorption assembly includes the outer shell and the separation membrane, and the pressure in the second cavity is lower than the pressure in the first cavity.

6. The gas detection device according to claim 4, characterized in that: The adsorption assembly includes the outer shell, the porous adsorption element, the first vacuum flange, and the second vacuum flange, wherein the first vacuum flange is located at the first communication position, and the second vacuum flange is located at the second communication position.

7. The gas detection device according to claim 1, characterized in that: The gas detection device further includes an exhaust gas treatment component. The cleaning component, the adsorption component, and the exhaust gas treatment component are connected in sequence. The exhaust gas treatment component is used to collect the target nuclide or discharge the target nuclide to the outside world. and / or, The gas detection device further includes a detection component, wherein the cleaning component, the adsorption component, and the detection component are connected in sequence, and the detection component is used to detect the target nuclide in the purge gas.

8. The gas detection device according to claim 7, characterized in that: The gas detection device includes the exhaust gas treatment component, the detection component, and a first control valve group, which is used to switch the on / off state between the adsorption component and the exhaust gas treatment component, and between the adsorption component and the detection component.

9. The gas detection device according to claim 1, characterized in that, The gas detection device also includes: A gas delivery assembly, connected to the adsorption assembly, is used to supply the radioactive gas to the adsorption assembly; The second control valve group is used to switch the on / off state between the adsorption component and the gas delivery component, and between the adsorption component and the cleaning component; The second control valve group is configured such that: when the adsorption component adsorbs the target nuclide, the adsorption component is connected to the gas delivery component and disconnected from the cleaning component; when the adsorption component releases the target nuclide, the adsorption component is disconnected from the gas delivery component and connected to the cleaning component, the heating component heats the adsorption component, and the preheating component preheats the purge gas.

10. The gas detection device according to claim 9, characterized in that: The gas detection device further includes a detection component, wherein the gas delivery component, the adsorption component, and the detection component are connected in sequence, and the detection component is used to detect the target nuclide in the radioactive gas.

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