Iodine adsorber core and iodine adsorber

Abstract

The iodine adsorber core body is used for adsorbing iodine in radioactive tail gas and is provided with a tail gas inlet, the tail gas inlet is in butt joint with a gas inlet hole, the iodine adsorber core body comprises a sealing gasket and a detection piece, the sealing gasket is annular, is arranged between a first end face and a second end face in a cushioned mode and is arranged around the tail gas inlet, and the detection piece is arranged around the tail gas inlet. An avoiding area is arranged at the annular center line of the sealing gasket, so that when the first end face and the second end face are connected in an attached mode, an annular sealing cavity surrounding the butt joint position of the tail gas inlet and the gas inlet hole is formed through sealing of the sealing gasket, and the detection piece communicates with the annular sealing cavity and is used for obtaining the sealing condition of the annular sealing cavity. And judging whether the iodine adsorber core body is mounted in place or not according to the sealing condition. The iodine adsorber core body is reasonable in structural arrangement and higher in sealing connection performance, setting conditions are provided for sealing detection, the airflow short circuit condition is effectively avoided, pollution leakage is avoided, and the invention further provides an iodine adsorber.

Description

Technical Field

[0001] The invention specifically relates to an iodine adsorber core and an iodine adsorber. Background Art

[0002] During the production process of nuclear fuel reprocessing plants, a large amount of radioactive tail gas is generated. These tail gases contain radioactive droplets and aerosols, which are highly corrosive and radioactive. They cannot be discharged directly into the environment and need to be purified. Process tail gas containing radioactive forms of iodine (such as elemental iodine, methyl iodide, etc.) is usually treated with iodine adsorbers.

[0003] In the prior art, the efficiency of the iodine adsorber can only be tested in the initial installation stage (i.e., the stage without radioactivity contamination). It is difficult to perform accurate testing after the core is replaced in the later stage. This is because the current testing methods generally involve obtaining the radioactivity in the incoming and outgoing airflows for comparison to obtain the efficiency test results. Therefore, during the installation stage, the body of the device has not been contaminated, and accurate radioactivity testing can be performed. However, once it is put into use, the body of the device is contaminated, and the obtained airflow radioactivity test results will be affected by interference, making it difficult to obtain effective results.

[0004] In this case, if the iodine adsorber core is not installed properly during the later replacement, it will cause airflow short circuit (i.e., output without adsorption and iodine removal and filtration), and it is difficult to detect this situation in time due to immature detection methods, which may eventually lead to more serious pollution leakage. In the nuclear fuel reprocessing plant that has been in operation, there have been cases of airflow short circuit caused by the iodine adsorber or filter not being installed properly, and the radioactive tail gas was directly sent to the chimney for discharge without effective treatment, causing pollution to the atmospheric environment. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an iodine adsorber core body in view of the above-mentioned deficiencies in the prior art. The core body has a reasonable structure, stronger sealing connection performance, and provides setting conditions for sealing detection, effectively avoiding airflow short-circuiting and avoiding pollution leakage. The present invention also provides an iodine adsorber.

[0006] The present invention provides an iodine adsorber core body, which is provided with a tail gas inlet, wherein a first end face where the tail gas inlet is located is fitted and connected with a second end face where an air inlet hole of the iodine adsorber is located, so that the tail gas inlet and the air inlet hole are butted against each other, the iodine adsorber core body comprises a sealing gasket and a detection component, the sealing gasket is annular, is cushioned between the first end face and the second end face, and is arranged around the tail gas inlet, and an escape area is provided at the annular center line of the sealing gasket, so that when the first end face and the second end face are fitted and connected, an annular sealing cavity around the butt joint of the tail gas inlet and the air inlet hole is formed by the sealing gasket, the detection component is connected with the annular sealing cavity, and is used for obtaining the sealing condition of the annular sealing cavity, and judging whether the iodine adsorber core body is installed in place according to the sealing condition.

[0007] Furthermore, the sealing gasket includes two annular sealing channels, one sealing channel surrounds the periphery of the other sealing channel, so that the area between the two sealing channels forms the avoidance area. When the first end face and the second end face are fitted and connected, the first end face, the second end face and the two sealing channels close the avoidance area in the middle, so that the avoidance area forms an annular sealing cavity surrounding the joint between the exhaust gas inlet and the air inlet.

[0008] Furthermore, the sealing gasket is arranged on the first end face / the second end face, and when the first end face and the second end face are fitted and connected, the opening of the avoidance area is closed by the second end face / the first end face to form an annular sealing cavity.

[0009] Furthermore, the iodine adsorber core also includes an adsorption material, which is in a cylindrical structure with a central cavity inside. One end of the central cavity is open as an exhaust gas inlet, and the other end is closed, so that the exhaust gas enters the central cavity through the exhaust gas inlet, and then flows out from the side after being adsorbed and removed by the adsorption material to remove iodine.

[0010] Furthermore, the iodine adsorber core also includes a protective net, the adsorption material is filled with iodine adsorbent particles to form a cylindrical structure, the inner and outer surfaces of the cylindrical structure are covered with the protective net, and in the adsorption material, the particle size of the iodine adsorbent particles close to the protective nets on both sides along the thickness direction is larger than the particle size of the iodine adsorbent particles in the middle.

[0011] Furthermore, the iodine adsorber core also includes end caps, both ends of the adsorbent material are connected with end caps, and the end cap at one end serves as a first end face and is provided with a tail gas inlet so that the radioactive tail gas enters the adsorbent material through the tail gas inlet for adsorption and iodine removal.

[0012] Furthermore, the detection component includes a connecting pipeline, a compressed gas supply device and a pressure measuring unit. The connecting pipeline is connected between the annular sealing chamber and the compressed gas supply device, and is used to input the compressed gas supplied by the compressed gas supply device into the annular sealing chamber so that the air pressure in the annular sealing chamber reaches a set pressure. The detection end of the pressure measuring unit is connected to the connecting pipeline, which is used to obtain the pressure condition in the annular sealing chamber through the connecting pipeline, and to determine that the iodine adsorber core is installed in place when the pressure drop in the annular sealing chamber is less than a set value within a set time.

[0013] Furthermore, the end opening of the connecting pipeline is provided on the second end surface at a position corresponding to the avoidance area, so that after the first end surface is fitted with the second end surface, the annular sealing cavity is connected.

[0014] The present invention also provides an iodine adsorber, comprising a shell and the above-mentioned iodine adsorber core, wherein an air inlet and an air outlet are provided on the wall surface of the shell, a connecting plate is provided in the inner cavity between the air inlet and the air outlet, and the air inlet hole is provided on the connecting plate serving as the first end face, and the iodine adsorber core is accommodated in the inner cavity of the shell and is installed on the side of the connecting plate facing the air outlet so that the exhaust gas inlet is connected to the air inlet hole.

[0015] Furthermore, in the inner cavity of the shell, a cavity serving as a buffer space is provided in the area between the air inlet and the connecting plate, so that the radioactive tail gas first reaches the cavity after entering the air inlet and then enters the iodine adsorber core through the air inlet hole.

[0016] Furthermore, the air inlet, the connecting plate and the air outlet are arranged sequentially from bottom to top, so that the radioactive tail gas passes through the air inlet, the connecting plate, the iodine adsorber core and the air outlet sequentially during the rising process in the shell.

[0017] The iodine adsorber core of the present invention is provided with an annular sealing gasket at the periphery of the exhaust gas inlet, so that when the iodine adsorber core is docked with the iodine adsorber inner cavity, an annular sealing belt is formed at the periphery of the docking position of the exhaust gas inlet and the air inlet hole, ensuring that the radioactive exhaust gas flows into the exhaust gas inlet after flowing out of the air inlet hole.

[0018] Moreover, this sealing belt is not just a conventional compression seal. Instead, an avoidance area is set so that the two fitting surfaces to be sealed form an annular sealing cavity sealed by the sealing gasket itself after fitting. Therefore, the sealing condition in the annular sealing cavity can be directly related to whether the sealing gasket can achieve good contact sealing between the first end face and the second end face.

[0019] And this sealed cavity is annular around the tail gas inlet and the docking position of the air inlet, so when all the circumferential positions of the docking position are strictly fitted, the annular sealed cavity as a whole has a good sealing situation. In this case, the radioactive gas flows into the tail gas inlet after flowing out from the air inlet, and all flows out after the iodine is adsorbed and removed by the iodine adsorber core, and no gas short circuit situation occurs. Therefore, the present invention is provided with a specific annular sealed cavity structure, and by detecting the sealed cavity situation, it is determined whether the iodine adsorber core is installed in place, which can not only improve the sealing strength, but also provide setting conditions for airflow short circuit detection, ensure that the iodine adsorber core is 100% invested in the adsorption and iodine removal work, effectively avoid the airflow short circuit situation, and avoid pollution leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the internal structure of the iodine adsorber core in Example 1 of the present invention;

[0021] Figure 2 is a schematic cross-sectional structure diagram of the iodine adsorber core in Example 1 of the present invention;

[0022] Figure 3 is a schematic diagram of the overall structure of the iodine adsorber core in Example 1 of the present invention;

[0023] Figure 4 is an enlarged view of the sealing gasket structure of the iodine adsorber core in Example 1 of the present invention;

[0024] Figure 5 It is a schematic diagram of the structure of the iodine adsorber in Example 2 of the present invention.

[0025] In the figure: 1. exhaust gas inlet; 2. sealing gasket; 21. annular sealing chamber; 22. sealing channel; 3. detection part; 31. connecting pipeline; 4. air inlet; 5. end cover; 6. adsorption material; 7. protective net; 8. shell; 81. air inlet; 82. air outlet; 83. connecting plate. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "upper", "lower" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience and simplification of the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present invention.

[0028] In the description of the present invention, the terms “first”, “second” and “third” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connect", "set", "install", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0030] Example 1

[0031] like Figures 1 to 5 As shown, the iodine adsorber core of the present embodiment is used to adsorb iodine in radioactive tail gas, and the core is provided with a tail gas inlet 1, and the first end face where the tail gas inlet 1 is located is fitted and connected with the second end face where the air inlet hole 4 of the iodine adsorber is located, so that the tail gas inlet 1 is butted with the air inlet hole 4, and the iodine adsorber core comprises a sealing gasket 2 and a detection member 3, the sealing gasket 2 is annular, and is arranged between the first end face and the second end face, and is arranged around the tail gas inlet 1, and an avoidance area is provided at the annular center line of the sealing gasket 2, and along the thickness of the sealing gasket 2 In the direction, the avoidance area is concave relative to the surface of the sealing gasket 2, so that when the sealing gaskets 2 on both sides of the avoidance area contact the docking surface (the docking surface refers to the first end face / the second end face), the avoidance area avoids the docking surface, so that when the first end face and the second end face are fitted and connected, the sealing gasket 2 is sealed to form an annular sealing cavity 21 surrounding the docking point between the exhaust gas inlet 1 and the air inlet hole 4, and the detection part 3 is connected to the annular sealing cavity 21 for obtaining the sealing condition of the annular sealing cavity 21, and judging whether the iodine adsorber core is installed in place according to the sealing condition.

[0032] In this embodiment, an annular sealing gasket 2 is arranged at the periphery of the exhaust gas inlet 1, so that when the iodine adsorber core is docked with the iodine adsorber inner cavity, an annular sealing belt is formed at the periphery of the docking position of the exhaust gas inlet 1 and the air inlet 4 to ensure that the radioactive exhaust gas flows out of the air inlet 4 and then flows into the exhaust gas inlet 1.

[0033] Moreover, this sealing belt is not just a conventional compression sealing form, but by setting an avoidance area, the two fitting surfaces to be sealed form an annular sealing cavity 21 sealed by the sealing gasket 2 itself after fitting. Therefore, the sealing condition in the annular sealing cavity 21 can be directly related to whether the sealing gasket 2 can achieve good contact sealing between the first end face and the second end face.

[0034] The annular sealed cavity 21 is in the shape of an annular shape surrounding the docking position of the tail gas inlet 1 and the air inlet 4. Therefore, when all the circumferential positions of the docking position are strictly fitted, the annular sealed cavity 21 as a whole has a good sealing condition. In this case, the radioactive gas flows out of the air inlet 4 and flows into the tail gas inlet 1. All of the radioactive gas flows out after being adsorbed and deiodinated by the iodine adsorber core, and no gas short circuit occurs. Therefore, the present embodiment sets a specific annular sealed cavity 21 structure, and can accurately determine whether the iodine adsorber core is installed in place by detecting the annular sealed cavity 21 situation, which can not only improve the sealing strength, but also provide setting conditions for airflow short circuit detection, ensuring that the iodine adsorber core is 100% invested in the adsorption and deiodination work, effectively avoiding airflow short circuit and avoiding pollution leakage.

[0035] In this embodiment, Figure 1 As shown, the sealing gasket 2 includes two annular sealing channels 22, and one sealing channel 22 surrounds the periphery of the other sealing channel 22, so that the area between the two sealing channels 22 forms an escape area. When the first end face and the second end face are fitted and connected, the first end face, the second end face and the two sealing channels 22 close the escape area in the middle, so that the escape area forms an annular sealing cavity 21 surrounding the joint between the exhaust gas inlet 1 and the air inlet 4.

[0036] This arrangement not only provides two-stage sealing measures to further improve the sealing performance, but also cleverly forms an annular sealing cavity 21 structure. The annular sealing cavity 21 itself can serve as an airtight sealing cavity, and its sealing condition also provides a means of detecting whether an airflow short circuit occurs. The size of the two sealing channels 22 can be selected according to the size of the core body and the processing accuracy of the sealing gasket 2, and can be located below the circular adsorbent filling area of ​​the core body, so as to ensure that the airflow does not short-circuit and maximize the air path channel with the minimum resistance.

[0037] Wherein, the sealing gasket 2 is arranged on the first end face / the second end face, and when the first end face and the second end face are fitted and connected, the opening of the avoidance area is closed by the second end face / the first end face to form an annular sealed cavity 21. For example, in the present embodiment, the sealing gasket 2 is arranged on the first end face of the iodine adsorption core, and when fitted, the opening of the avoidance area is closed by the second end face. In other embodiments, the sealing gasket 2 may also be arranged on the second end face. In addition, the first end face and the second end face may also adopt structural forms such as curved surfaces that are butted against each other, and avoidance grooves are provided at the positions corresponding to the sealing gasket 2 to form a sealed cavity whose opening is sealed by the sealing gasket 2, but no specific description is given in the present embodiment.

[0038] In this embodiment, the iodine adsorber core also includes an adsorbent material 6, which is in a cylindrical structure and has a central cavity inside. One end of the central cavity is open as a tail gas inlet 1, and the other end is closed, so that the tail gas enters the central cavity through the tail gas inlet 1, and then flows out from the side after being adsorbed and removed by the adsorbent material 6. The adsorbent material 6 of the cylindrical structure forms a central cavity in the middle, so that the tail gas will be adsorbed and removed from the adsorbent material 6 as the side wall after entering the central cavity, which optimizes the direction of the airflow. This structural type can make full use of the longitudinal space in the core, and the adsorption area is larger under the premise of ensuring a certain adsorbent bed height, and the processing capacity of the iodine adsorber is significantly improved under the same gas velocity conditions.

[0039] In the prior art, the structural dimensions of the iodine adsorber filter core are strictly limited due to the size of the container that can accommodate the maintenance of the iodine adsorber filter core, resulting in a low gas volume processed by a single iodine adsorber or filter. There is even a need to split and parallelize the tail gas purification system because the gas volume does not meet the requirements, which brings inconvenience to the system settings, equipment quantity and investment, equipment room space requirements, and the frequency of personnel inspection and maintenance operations. It is economically inefficient and does not meet the principle of the lowest reasonably achievable in the optimization method of radiation protection. It is particularly important and urgent to further increase the gas volume processed by a single iodine adsorber.

[0040] After the sealing gasket 2 of the present embodiment uses a double-layer sealing structure, if the iodine adsorber still uses the original filling structure (the whole block structure does not have a central cavity), the double-layer sealing area will block the flow of tail gas, causing disturbances to the gas flow field; in addition, the loss of a portion of the air intake area will further increase the equipment resistance. If you want to avoid the influence of the airflow dead zone, the adsorbent filling area needs to be raised and moved up to the area where the airflow is evenly mixed, that is to say, the height of the adsorbent bed also has certain losses or wastes. That is, if the original adsorbent filling structure is used, in order to achieve a double-layer seal, the air intake area will be reduced and the flow rate will increase. In order to achieve the same adsorption effect, more adsorbents are needed, and the equipment resistance is also increased. In addition, useless areas appear in the height direction, wasting space.

[0041] Compared with the traditional filling structure, when the adsorption material 6 of this embodiment is used for the iodine adsorption core, the cylindrical structure itself can optimize the airflow direction and make full use of the longitudinal space. Under the premise of ensuring a certain adsorbent bed height, the adsorption area is larger, and the iodine adsorber processing capacity is significantly improved under the same gas velocity conditions. The double-channel sealing pad 2 structure can be used for the air tightness test of the iodine adsorber core after installation, thereby improving operational safety.

[0042] In the present embodiment, the iodine adsorber core also includes a protective net 7, and the adsorbent material 6 is filled with iodine adsorbent particles to form a tubular structure. The inner and outer surfaces of the tubular structure are covered with the protective net 7. In the adsorbent material 6, the iodine adsorbent particle diameter near the protective nets 7 on both sides along the thickness direction is greater than the iodine adsorbent particle diameter in the middle. The protective net 7 can maintain the structure of the adsorbent material 6 and can not block the exhaust gas outflow. The iodine adsorbent particle diameter is arranged in the above manner, which can avoid small-size particles from spilling out from the mesh of the protective net 7, and can achieve high adsorption efficiency through the small-size particles in the middle. At the same time, since large-size particles are used on both sides, the protective net 7 itself can also adopt a structure with a larger mesh gap, which can effectively reduce the exhaust gas flow resistance, that is, this reasonable structure can avoid the adsorbent from spilling, and can also reduce resistance on the basis of ensuring adsorption efficiency.

[0043] In this embodiment, the overall particle size range of the iodine adsorbent particles is 2mm to 5mm, within which both the adsorption effect and the resistance characteristics can be taken into account. During the filling process, the particles close to 5mm (for example, 4 to 5mm) are placed close to the protective nets on both sides, and the remaining small-size particles are placed in the middle. Compared with keeping all particle sizes within the optimal particle size range of 3 to 4mm, this embodiment is beneficial in increasing the proportion of this range.

[0044] In this embodiment, the iodine adsorber core further includes an end cap 5, both ends of the adsorbent material 6 are connected with the end cap 5, and the end cap 5 at one end is used as a first end face, and a tail gas inlet 1 is provided, so that the radioactive tail gas enters the adsorbent material 6 through the tail gas inlet 1 for adsorption and iodine removal. In this embodiment, the sealing gasket 2 can be arranged on the end cap 2 with the tail gas inlet 1, and the end cap 5 makes the core structure more regular, provides a flat docking surface for the docking of the tail gas inlet 1 and the air inlet 4, and also provides a flat setting surface for the sealing gasket 2.

[0045] During specific filling, one side end cover and the protective net can be built into a cylindrical shape, and then the particles are filled, and then the other side end cover is closed. In this embodiment, a vertical rod structure can also be set on the core body to facilitate clamping and replacing the core body itself.

[0046] In this embodiment, Figure 4As shown, the detection component 3 includes a connecting pipeline 31, a compressed gas supply device and a pressure measuring unit. The connecting pipeline 31 is connected between the annular sealing chamber 21 and the compressed gas supply device, and is used to input the compressed gas supplied by the compressed gas supply device into the annular sealing chamber 21 so that the air pressure in the annular sealing chamber 21 reaches the set pressure. The detection end of the pressure measuring unit is connected to the connecting pipeline 31, which is used to obtain the pressure condition in the annular sealing chamber 21 through the connecting pipeline 31, and to determine that the iodine adsorber core is installed in place and the seal is effective when the pressure drop in the annular sealing chamber 21 is less than the set value within the set time.

[0047] Specifically, Figure 4 As shown, the end opening of the connecting pipeline 31 is opened on the second end face, located at a position corresponding to the avoidance area on the sealing pad 2, so that after the first end face and the second end face are fitted, the annular sealing cavity 21 is connected. This opening setting position can ensure that the connecting pipeline 31 is connected to the annular sealing cavity 21, so that the pressure situation in the cavity can be judged by measuring the pressure situation in the connecting pipeline 31, and the sealing performance of the sealing pad 2 itself will not be affected, and the difficulty of setting the sealing pad 2 will not be increased. Compressed gas supply equipment and pressure measuring unit (not shown in the figure, can be corresponding to conventional equipment on the market) can be arranged outside the equipment room where the iodine adsorber is located (reducing the impact of radiation protection, a position where personnel can operate), and the pipe body of the connecting pipeline 31 can extend outside the equipment room, and then communicate with the compressed gas supply equipment and the pressure measuring unit, so as to facilitate personnel operation and observation.

[0048] The compressed gas supply device can supply compressed air, and perform air tightness test after the core is installed or replaced. The test pressure during the test is 0.03Mpa (i.e. the set pressure in the annular sealing chamber 21 reaches 30kPa(g)), and the pressure is maintained for 10 minutes without leakage (i.e. the set time is 10 minutes, the pressure drop setting value is 1kPa, i.e. the pressure drop is <0.001Mpa(1kPa)), which is qualified, and the core is judged to be installed in place.

[0049] The connecting pipeline 31 can be formed by one pipeline or multiple pipelines connected in series. In this embodiment, the pressure measuring unit pipeline and the iodine adsorber branch (connected to the annular sealing chamber 21) are connected in series to form the connecting pipeline 31, wherein the pressure measuring unit adopts a mobile pressure measuring device. In the connecting pipeline 31, a first valve is provided at the bottom of the pressure measuring unit, and a second valve is provided on the iodine adsorber branch. A pressure relief valve can also be provided on the connecting pipeline 31.

[0050] ① Before replacing the core, first test the sealing of the connecting pipe 31 and each valve:

[0051] Open the first valve under the mobile pressure measuring device, adjust the pressure in the connecting pipeline 31 to 30 kPa (g), if the pressure is too high at this time, open the pressure relief valve to release the pressure, and close the pressure relief valve after the pressure is released; then open the second valve on the branch of the iodine adsorber to be tested, adjust the pressure in the connecting pipeline 31 again, and keep it at 30 kPa (g), wait for 10 minutes, if the pressure drop is less than 1 kPa, it means that the connecting pipeline 31 has good sealing performance; then, open the pressure relief valve, release the pressure in the connecting pipeline 31, and then close the pressure relief valve, the second valve on the branch, and the first valve under the mobile pressure measuring device in sequence;

[0052] After replacing the iodine adsorber core, an airtightness test is required:

[0053] ② First, open the first valve under the mobile pressure measuring device, adjust the pressure in the connecting pipe 31 to 30 kPa (g), and wait for 10 minutes. At this time, the pressure drop should be less than 1 kPa;

[0054] ③ Open the second valve on the branch of the iodine adsorber to be tested, adjust the pipeline pressure to 30kPa(g), wait for about 5 minutes after the pressure stabilizes, and close the first valve under the mobile pressure measuring device. After 10 minutes, if the pipeline pressure is still maintained at 29kPa(g) or above, it is considered that the sealing test has passed; then open the pressure relief valve, and when the pressure in the connecting pipeline 31 is displayed as 0, close the pressure relief valve and the second valve on the branch in turn. The sealing test is over.

[0055] The iodine adsorber core of this embodiment can be used in the field of nuclear fuel post-processing, specifically for filtering and adsorbing process exhaust gas containing radioactive iodine (such as elemental iodine, methyl iodide, etc.), and can be used in an iodine adsorber containing the iodine adsorber core.

[0056] Specifically, the core structure includes two end caps 5, which are respectively an upper end cap 5 and a lower end cap 5 (the lower end cap 5 is an end cap 5 provided with an exhaust gas inlet 1 and a sealing pad 2), and an iodine adsorbent filling area (including a protective net 7) is provided between the two end caps 5, and a double-channel sealing pad 2 is also included. The iodine adsorbent filling area is a cylindrical structure, and the airflow enters from the middle cavity of the top or bottom of the core (the present embodiment is the bottom), and is discharged from the cylinder wall around the cylinder after the adsorbent material adsorbs and removes iodine. The protective net 7 can both maintain the core structure and avoid blocking the exhaust gas outflow. The iodine adsorber is also optimized in the sealing structure, and a layer of sealing ring is added at the contact point between the core and the shell, which is optimized to a double-layer sealing ring structure so as to carry out sealing detection after replacing the core, and prevent the problem of airflow short circuit caused by not pressing between the core and the core seat. A sealing detection air pipe (connecting pipeline 31) is extended in the middle of the two layers of sealing rings, and a pressure holding test is carried out after each core replacement. The double-channel sealing gasket 21 can be used for air tightness test after the iodine adsorber core is installed, and is used to confirm that the iodine adsorber core is installed in place, has good sealing and no risk of short circuit of the air path, and improves the operation safety. The total adsorption efficiency of the iodine adsorber core of this structure for various radioactive forms of iodine (such as elemental iodine, methyl iodide, etc.) is not less than 99.9%.

[0057] Example 2

[0058] The iodine adsorber of this embodiment is used for adsorption and filtration of iodine in radioactive tail gas and can be installed below the building surface, such as Figure 5 As shown, the iodine adsorber includes a shell 8 and an iodine adsorber core in Example 1, an air inlet 81 and an air outlet 82 are provided on the wall of the shell 8, a connecting plate 83 is provided at a position between the air inlet 81 and the air outlet 82 in the inner cavity, an air inlet 4 is provided on the connecting plate 83 as a first end face, and the iodine adsorber core is accommodated in the inner cavity of the shell 8 and is installed on the side of the connecting plate 83 facing the air outlet 82 so that the exhaust gas inlet 1 is connected to the air inlet 4.

[0059] The iodine adsorber of this embodiment can significantly improve the processing capacity of a single device by using the iodine adsorber core in Example 1, and has an optimization effect on the system setting of the process tail gas purification system of the nuclear fuel reprocessing plant, the number of equipment and equipment investment, the space requirements of the equipment room, the frequency of personnel inspection and maintenance operations, etc., significantly improves the economic efficiency, and is conducive to the optimization management of radiation protection. In the later stage of operation, after the core is replaced, an airtightness test can be performed to ensure that the iodine adsorber core is installed in place without airflow short-circuit problems, further improve safety, and reduce the risk of tail gas being discharged into the environment without radioactive purification treatment.

[0060] In this embodiment, a cavity as a buffer space is provided in the inner cavity of the shell 8 in the area between the air inlet 81 and the connecting plate 83, so that the radioactive tail gas first reaches the cavity after entering the air inlet 81 and then enters the iodine adsorber core through the air inlet 4. This buffer cavity can not only provide tail gas buffering function for the core, but also collect and discharge condensate in this area if the moisture content of the gas is high, so as to achieve gas-liquid separation and further improve the efficiency of subsequent tail gas adsorption.

[0061] In this embodiment, the air inlet 81, the connecting plate 83 and the air outlet 82 are arranged sequentially from bottom to top, so that the radioactive tail gas passes through the air inlet 81, the connecting plate 83, the iodine adsorber core and the air outlet 82 in sequence during the rising process in the shell 8. This bottom-to-top filtering flow direction allows the connecting plate 83 (or the core support plate) to support the core from the bottom to avoid disturbance of the airflow by the supporting structure, and the air inlet 81 is located at the lower position to facilitate the collection of condensate.

[0062] In general, the iodine adsorber of this embodiment includes a shell 8 and a core body. The core body adopts the iodine adsorber core body of Example 1, and the core body is arranged in the shell 8; an air inlet 81 and an air outlet 82 are arranged on the shell 8. The gas enters from the air inlet 81, is adsorbed by the adsorbent material to remove iodine, and then is discharged to the outside of the iodine adsorber through the air outlet 82.

[0063] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An iodine adsorber core, characterized in that: A tail gas inlet (1) is provided, and a first end face where the tail gas inlet (1) is located is fitted and connected to a second end face where an iodine adsorber air inlet hole (4) is located, so that the tail gas inlet (1) is butted against the air inlet hole (4). The iodine adsorber core comprises a sealing pad (2) and a detection element (3). The sealing gasket (2) is annular, and is arranged between the first end face and the second end face, and is arranged around the exhaust gas inlet (1). A relief area is provided at the annular center line of the sealing gasket (2), so that when the first end face and the second end face are fitted and connected, the sealing gasket (2) is sealed to form an annular sealing cavity (21) around the joint between the exhaust gas inlet (1) and the air inlet hole (4). The detection member (3) is connected to the annular sealing cavity (21) and is used to obtain the sealing condition of the annular sealing cavity (21), and to determine whether the iodine adsorber core is installed in place according to the sealing condition.

2. The iodine adsorber core according to claim 1, characterized in that: The sealing gasket (2) comprises two annular sealing channels (22). One sealing path (22) surrounds the periphery of another sealing path (22), so that the area between the two sealing paths (22) forms the avoidance area. When the first end face and the second end face are fitted and connected, the first end face, the second end face and the two sealing channels (22) close the escape area in the middle, so that the escape area forms an annular sealing cavity (21) surrounding the joint between the exhaust gas inlet (1) and the air inlet hole (4).

3. The iodine adsorber core according to claim 1 or 2, characterized in that: The sealing gasket (2) is arranged on the first end surface / the second end surface, and when the first end surface and the second end surface are fitted and connected, the opening of the avoidance area is closed by the second end surface / the first end surface to form an annular sealing cavity (21).

4. The iodine adsorber core according to claim 1, characterized in that: The invention also comprises an adsorption material (6), wherein the adsorption material (6) is in a cylindrical structure and has a central cavity inside. One end of the central cavity is open to serve as an exhaust gas inlet (1), and the other end is closed, so that the exhaust gas enters the central cavity through the exhaust gas inlet (1) and then flows out from the side after being adsorbed and deiodized by the adsorption material (6).

5. The iodine adsorber core according to claim 4, characterized in that: It also includes a protective net (7), The adsorption material (6) is filled with iodine adsorbent particles to form a cylindrical structure, and the inner and outer surfaces of the cylindrical structure are covered with the protective net (7). In the adsorption material (6), the particle size of the iodine adsorbent particles close to the protective nets (7) on both sides along the thickness direction is larger than the particle size of the iodine adsorbent particles in the middle.

6. The iodine adsorber core according to claim 4, characterized in that: It also includes an end cap (5), and both ends of the adsorption material (6) are connected to the end cap (5). The end cap (5) at one end serves as a first end surface and is provided with a tail gas inlet (1) so that the radioactive tail gas can enter the adsorption material (6) through the tail gas inlet (1) to be adsorbed and iodine removed.

7. The iodine adsorber core according to claim 1, characterized in that: The detection element (3) comprises a connecting pipeline (31), a compressed gas supply device and a pressure measuring unit. The connecting pipeline (31) is connected between the annular sealed chamber (21) and the compressed gas supply device, and is used to input the compressed gas supplied by the compressed gas supply device into the annular sealed chamber (21), so that the gas pressure in the annular sealed chamber (21) reaches the set pressure. The detection end of the pressure measuring unit is connected to the connecting pipeline (31) and is used to obtain the pressure condition in the annular sealing chamber (21) through the connecting pipeline (31), and to determine that the iodine adsorber core is installed in place when the pressure drop in the annular sealing chamber (21) is less than a set value within a set time.

8. The iodine adsorber core according to claim 7, characterized in that: The end opening of the connecting pipeline (31) is opened on the second end surface and is located at a position corresponding to the avoidance area, so that after the first end surface and the second end surface are attached to each other, the annular sealing cavity (21) is connected.

9. An iodine adsorber, characterized in that: comprising a shell (8) and an iodine adsorber core according to any one of claims 1 to 8, An air inlet (81) and an air outlet (82) are provided on the wall surface of the shell (8), and a connecting plate (83) is provided in the inner cavity at a position between the air inlet (81) and the air outlet (82). The air inlet (4) is formed on the connecting plate (83) serving as the first end surface. The iodine adsorber core is accommodated in the inner cavity of the housing (8) and is mounted on the side of the connecting plate (83) facing the gas outlet (82) so that the tail gas inlet (1) is butted against the gas inlet hole (4).

10. The iodine adsorber according to claim 9, characterized in that: In the inner cavity of the shell (8), a cavity serving as a buffer space is provided in the area between the air inlet (81) and the connecting plate (83), so that the radioactive tail gas first reaches the cavity after entering the air inlet (81) and then enters the iodine adsorber core through the air inlet hole (4).

11. The iodine adsorber according to claim 9, characterized in that: The air inlet (81), the connecting plate (83) and the air outlet (82) are arranged in sequence from bottom to top, so that the radioactive tail gas passes through the air inlet (81), the connecting plate (83), the iodine adsorber core and the air outlet (82) in sequence during its ascent in the shell (8).

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