Nuclear facility aerosol nuclide activity monitoring device

Abstract

The invention provides a nuclear facility aerosol nuclide activity monitoring device, which comprises a detector shell, the outer wall of the detector shell is provided with a detector interface, an air inlet pipe interface and an exhaust pipe interface, the air inlet pipe interface is outwards connected with an air inlet pipeline, and the exhaust pipe interface is outwards connected with an exhaust pipeline; the radiation detector is connected to the detector interface; the paper feeding mechanism is arranged in the detector shell and comprises filter paper which extends between the detection end of the radiation detector and the air inlet pipe connector; the output end of the moving assembly is connected with the filter paper; the shielding body assembly comprises an external shielding body and an internal shielding body, the radiation detector is sleeved with the external shielding body, the internal shielding body is arranged in the detector shell, and the filter paper is located between the detection end of the radiation detector and the internal shielding body. According to the invention, the change condition of the activity concentration of the aerosol radionuclide in the airborne effluent can be obtained in time.

Description

Technical Field

[0001] The invention relates to the technical field of radiation environment monitoring, and in particular to a monitoring device for aerosol nuclide activity of nuclear facilities. Background Art

[0002] Airborne radioactive effluents emitted during the operation of nuclear power plants are purified and released into the atmosphere through chimneys. Nuclear power plants need to monitor the airborne radioactive effluents they emit. Monitoring items include inert gases, iodine, aerosols, etc. The measurement content includes the total emission, emission concentration, and the content of major nuclides. In the existing technology, the collected samples are placed in the laboratory for analysis, and there is a problem that the changes in the activity concentration of aerosol radionuclides in the airborne effluents cannot be obtained in time. Therefore, there is room for improvement. Summary of the invention

[0003] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a monitoring device for aerosol nuclide activity in nuclear facilities, so as to solve the problem in the prior art that changes in the activity concentration of aerosol radionuclides in airborne effluents cannot be obtained in a timely manner.

[0004] In order to achieve the above-mentioned and other related purposes, the present invention provides a monitoring device for aerosol nuclide activity in a nuclear facility, comprising:

[0005] The detector housing has an outer wall provided with a detector interface, an air intake pipe interface and an exhaust pipe interface, wherein the air intake pipe interface is externally connected to an air intake pipeline, and the exhaust pipe interface is externally connected to an exhaust pipeline;

[0006] A radiation detector, disposed at the detector interface;

[0007] The paper feeding mechanism is arranged inside the detector housing and includes:

[0008] Filter paper, extending between the detection end of the radiation detector and the air inlet pipe interface;

[0009] a moving component, an output end of which is connected to the filter paper; and

[0010] A shielding body assembly, comprising an external shielding body and an internal shielding body, wherein the external shielding body is sleeved on the outside of the radiation detector, the internal shielding body is arranged inside the detector housing, and the filter paper is located between the detection end of the radiation detector and the internal shielding body;

[0011] Wherein, the paper feeding mechanism is used to move the filter paper at the air inlet pipe interface to the detection end of the radiation detector.

[0012] In one embodiment of the present invention, the monitoring device further includes a sealing gasket and a sealing ring, the paper feeding mechanism is pull-out connected to the detector housing, a sealing ring is provided on one side of the paper feeding structure close to the detector housing, and a sealing gasket is provided at the detector interface.

[0013] In one embodiment of the present invention, the moving component includes a driving motor, a driving shaft, a driven shaft, and a filter paper cylinder. The driving shaft is connected to the output end of the driving motor, and the filter paper cylinder is respectively sleeved on the driving shaft and the driven shaft. The filter paper is connected to the filter paper cylinder of the driving shaft and the filter paper cylinder of the driven shaft.

[0014] In one embodiment of the present invention, the paper feeding mechanism further includes a counting shaft and a counting assembly, wherein the counting shaft is arranged between the driving shaft and the driven shaft and is located on one side of the filter paper, and the driving shaft, the driven shaft and the counting shaft rotate synchronously;

[0015] The counting component calculates the moving distance of the filter paper based on the number of rotations of the counting shaft.

[0016] In one embodiment of the present invention, the counting component includes a gear cylinder and a photoelectric sensor, the gear cylinder is sleeved and connected to the outside of the counting shaft, the photoelectric sensor is arranged on one side of the counting shaft, and the detection end of the photoelectric sensor faces the gear of the gear cylinder.

[0017] In one embodiment of the present invention, inside the detector housing, the driving shaft and the counting shaft are located on a side close to the radiation detector, and the driven shaft is located on a side close to the air intake pipe interface.

[0018] In one embodiment of the present invention, the direction between the detection end of the radiation detector and the air inlet pipe interface is recorded as a connecting line direction, and the extending direction of the filter paper is parallel to the connecting line direction.

[0019] In one embodiment of the present invention, the paper feeding mechanism further includes a pressure difference component, the pressure difference component includes a pressure difference gauge, the pressure difference gauge is connected to the air intake pipe through a first pipe, and the pressure difference gauge is connected to the exhaust pipe through a second pipe;

[0020] The differential pressure gauge generates a differential pressure signal when the air pressure difference between the first pipe and the second pipe reaches a preset threshold value, and the drive motor moves the filter paper at the air inlet pipe interface to the detection end of the radiation detector according to the differential pressure signal.

[0021] In one embodiment of the present invention, the external shielding body comprises a bottom shielding body, a middle shielding body and a top shielding body, the bottom shielding body and the middle shielding body are ring-shaped, and the top shielding body is cap-shaped;

[0022] The bottom shielding body is arranged on the outer wall of the detector housing, the middle shielding body is connected to the bottom shielding body, and the top shielding body is connected to the middle shielding body.

[0023] In one embodiment of the present invention, the ventilation holes are provided on the side walls of the bottom shielding body and the middle shielding body, and the wire threading holes are provided on the side walls of the top shielding body for connecting wires to the radiation detector.

[0024] In one embodiment of the present invention, the bottom shield, the middle shield and the top shield are filled with lead.

[0025] In one embodiment of the present invention, the detector interface and the air inlet pipe interface are opened on the top of the detector housing, and the exhaust pipe interface is opened on the side wall of the detector housing.

[0026] As described above, the monitoring device for aerosol nuclide activity in a nuclear facility of the present invention can timely obtain the change of aerosol radionuclide activity concentration in airborne effluent. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the operation of a monitoring device for aerosol nuclide activity in a nuclear facility provided by one embodiment of the present invention.

[0028] Figure 2 A front view of a device for monitoring the activity of aerosol nuclides in nuclear facilities provided in one embodiment of the present invention.

[0029] Figure 3 An embodiment of the present invention provides Figure 2 Schematic diagram of the AA section.

[0030] Figure 4 An embodiment of the present invention provides Figure 2 Schematic diagram of the cross section along the BB direction.

[0031] Figure 5 A three-dimensional schematic diagram of a paper feeding mechanism provided in one embodiment of the present invention.

[0032] Figure 6 A schematic diagram of the inner angle of a paper feeding mechanism provided in an embodiment of the present invention.

[0033] Figure 7 An embodiment of the present invention provides Figure 6 Schematic diagram of the CC section.

[0034] Figure 8 An embodiment of the present invention provides Figure 7Enlarged schematic diagram of point E in the middle.

[0035] Fig. 9 An embodiment of the present invention provides Figure 6 Schematic diagram of the DD section.

[0036] Fig.10 A schematic structural diagram of a radiation detector provided in one embodiment of the present invention.

[0037] Fig.11 A schematic structural diagram of an external shielding body provided in one embodiment of the present invention.

[0038] Fig.12 A schematic structural diagram of a bottom shielding body provided in one embodiment of the present invention.

[0039] Fig.13 An embodiment of the present invention provides Fig.12 Schematic diagram of the FF section.

[0040] Fig.14 An embodiment of the present invention provides Fig.12 The corresponding schematic diagram on the right.

[0041] Fig.15 A schematic structural diagram of a middle shielding body provided in one embodiment of the present invention.

[0042] Fig.16 An embodiment of the present invention provides Fig.15 Schematic diagram of the GG section.

[0043] Fig.17 An embodiment of the present invention provides Fig.15 The corresponding schematic diagram on the right.

[0044] Fig.18 A schematic structural diagram of a top shielding body provided in one embodiment of the present invention.

[0045] Fig.19 An embodiment of the present invention provides Fig.18 Schematic diagram of the HH section.

[0046] Fig. 20 A schematic structural diagram of an internal shielding body provided in one embodiment of the present invention.

[0047] Fig.21 An embodiment of the present invention provides Fig. 20 Schematic diagram of the cross section along the II axis.

[0048] Fig. 22 A schematic diagram of the operation of a device for monitoring the activity of aerosol nuclides in nuclear facilities provided in yet another embodiment of the present invention.

[0049] Reference numerals

[0050] 10. Detector housing; 101. Detector rear cover; 102. Detector bracket; 103. Detector buffer pad; 110. Detector interface; 120. Air intake pipe interface; 121. Air intake pipe; 130. Exhaust pipe;

[0051] 20. Radiation detector; 210. Sealing gasket; 220. Detector inner sleeve;

[0052] 30. Paper feeding mechanism; 301. Front cover; 302. Plum blossom hand wheel; 303. Paper feeding handle; 304. Mounting studs; 305. Guide piece;

[0053] 310, filter paper; 311, paper feed mounting plate; 320, moving assembly; 330, sealing ring;

[0054] 321, driving shaft; 3210, driving shaft nut; 3211, driving motor;

[0055] 322, driven shaft; 3220, driven shaft nut; 3221, bearing; 3222, damping seat; 3223, driven shaft pressure plate; 3224, damping cover; 3225, damping pressure plate; 3226, damping pad;

[0056] 323, filter paper cylinder; 324, guide shaft; 325, counting shaft; 3251, gear cylinder; 3252, counting shaft pressing piece; 326, photoelectric sensor;

[0057] 410, external shielding body; 4100, ventilation hole; 4101, lead filling; 4102, threading hole;

[0058] 411, bottom shielding body; 4111, bottom shielding body bottom plate; 4112, bottom shielding body inner cavity; 4113, bottom shielding body partition; 4114, bottom shielding body handle;

[0059] 412, middle shielding body; 4121, middle shielding body bottom plate; 4122, middle shielding body partition; 4123, middle shielding body inner cavity; 4124, threaded sleeve; 4125, hexagon socket screw; 4126, threaded column; 4127, middle shielding body handle;

[0060] 413, top shielding body; 4131, bottom plate of top shielding body; 4132, top of top shielding body;

[0061] 420, internal shielding body; 421, internal shielding body bottom plate; 422, internal shielding body top plate;

[0062] 510, differential pressure gauge; 520, first pipeline; 530, second pipeline. DETAILED DESCRIPTION

[0063] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0064] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0065] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0066] See also Figures 1 to 22 The present invention proposes a monitoring device for aerosol nuclide activity in nuclear facilities, which can be applied to the monitoring scenario of airborne radioactive effluents discharged by nuclear power plants. The present invention can perform online measurement of aerosol nuclide identification and other radioactive activity concentrations in airborne effluents of nuclear facilities, replacing sampling and laboratory analysis work and reducing manual input. The following is a detailed description through specific embodiments.

[0067] See also Figure 1 , Figure 2 , Figure 3 and Figure 4 In one embodiment of the present invention, the present invention provides a monitoring device for aerosol nuclide activity in a nuclear facility, which may include a detector housing 10, a radiation detector 20, a paper feed mechanism 30, and a shielding assembly. The detector housing 10 is the installation body of the monitoring device, and the detector housing 10 may be used to install the radiation detector 20, the paper feed mechanism 30, and the shielding assembly.

[0068] Specifically, the outer wall of the detector housing 10 is provided with a detector interface 110, an air intake pipe interface 120 and an exhaust pipe interface. Figure 1 As shown, the detector interface 110 can be used to externally mount the radiation detector 20. Figure 1 and Figure 2As shown, the air inlet pipe interface 120 can be used to connect to an air inlet pipe 121, and the air inlet pipe 121 is used to receive the airborne effluent of the nuclear facility and temporarily store it in the detector housing 10. Figure 3 As shown, the exhaust pipe interface can be used to connect to an exhaust duct 130 externally, and the exhaust duct 130 can be used to discharge the airborne effluent of the nuclear facility in the detector housing 10.

[0069] Specifically, the radiation detector 20 may be connected to the detector interface 110. The radiation detector 20 may be a cadmium zinc telluride (CZT, CdZnTe) semiconductor detector, and is used for nuclide identification and nuclide activity concentration measurement of airborne effluent aerosol. The cadmium zinc telluride (CZT) semiconductor detector is a new type of semiconductor detector. Compared with the traditional sodium iodide (NaI) detector and high purity germanium (HPGe) detector, the cadmium zinc telluride (CZT) semiconductor detector has high energy resolution, large linear range of measurement, relatively small volume, and can work at room temperature.

[0070] Specifically, the paper feeding mechanism 30 is disposed inside the detector housing 10. The paper feeding mechanism 30 may include at least a filter paper 310 and a moving assembly 320. The filter paper 310 may provide a filtering environment for aerosol particles in the air intake pipe 121, and the aerosol particles may be deposited on the filter paper 310. The filter paper 310 may extend between the detection end of the radiation detector 20 and the air intake pipe interface 120, such as Figure 1 As shown, a portion of the filter paper 310 may be arranged in a straight line segment, and the rest of the filter paper 310 may be arranged in an arc line, so that the filter paper 310 can be turned and moved under the action of the moving assembly 320. The output end of the moving assembly 320 is connected to the filter paper 310. The paper feeding mechanism 30 is used to move the filter paper 310 at the air inlet pipe interface 120 to the detection end of the radiation detector 20, that is, the paper feeding mechanism 30 is used to move the filter paper 310 at the air inlet pipe interface 120 to the detector interface 110.

[0071] Specifically, the shielding assembly may include an external shielding body 410 and an internal shielding body 420, and the shielding body assembly is used to shield external radiation. Figure 1 and Figure 2The radiation detector 20 and the external shielding body 410 shown can be arranged outside the detector housing 10, and the external shielding body 410 is sleeved outside the radiation detector 20, and the side wall of the external shielding body 410 is provided with ventilation holes 4100. Since the radiation detector 20 needs ventilation and heat dissipation and cannot be sealed, the ventilation holes 4100 can play a role in ventilation and heat dissipation. The internal shielding body 420 is arranged inside the detector housing 10, and the filter paper 310 can be located between the detection end of the radiation detector 20 and the internal shielding body 420. The filter paper 310 is acid-resistant and hydrophobic, the thickness of the filter paper 310 can be 0.1 mm, the width of the filter paper 310 can be 47 mm, the length of the filter paper 310 can be 20 meters, and the effective sampling diameter of the filter paper 310 can be 20 mm.

[0072] It can be seen from this that Figures 1 to 4 In the embodiment, filter paper 310 is provided at the air inlet interface 120, filter paper 310 is also provided at the detector interface 110, and a radiation detector 20 is provided at the top of the detector interface 110, and filter paper 310 and an internal shielding body 420 are provided at the bottom of the detector interface 110 in sequence. The interior of the detector housing 10 is sealed, and the inflow and outflow of airborne effluents of the nuclear facility are realized only between the air inlet interface 120 and the exhaust duct 130, and the detector interface 110 is in a sealed state. As for the radiation detector 20 and the shielding body assembly, since a ventilation hole 4100 is provided on the external shielding body 410, the radiation detector 20 is not sealed, and ventilation and heat dissipation can be performed.

[0073] See also Figure 1 , Figure 2 and Figure 3 In one embodiment of the present invention, the detector interface 110 and the air inlet pipe interface 120 may be provided at the top of the detector housing 10, and the exhaust pipe interface 130 may be provided on the side wall of the detector housing 10. Figure 2 As shown, a detector bracket 102 and a detector buffer pad 103 may be installed at the bottom of the detector housing 10. The detector bracket 102 is connected to the bottom of the detector housing 10, and the detector buffer pad 103 is connected to the bottom of the detector bracket 102 to reduce wear between the detector bracket 102 and the ground.

[0074] See also Figure 1 , Figure 2 and Figure 3 and Figure 4 In one embodiment of the present invention, a detector rear cover 101 is provided on one (rear) side of the detector housing 10 , and on the other (front) side of the detector housing 10 , a paper feeding mechanism 30 is pull-out connected to the detector housing 10 .

[0075] See also Figure 4 , Figure 5 , Figure 6 and Figure 7 In one embodiment of the present invention, in the paper feeding mechanism 30, the paper feeding mechanism 30 may include a front cover plate 301, a plum blossom hand wheel 302, a paper feeding handle 303, a mounting stud 304, a guide member 305 and a paper feeding mounting plate 311.

[0076] Specifically, Figure 5 As shown, the front cover 301 is the installation body of the paper feeding mechanism 30, and the front cover 301 is provided with a plum blossom hand wheel 302 and a paper feeding handle 303, which play the role of pulling the front cover 301. Figure 7 As shown, the mounting stud 304 is connected to the inner side of the front cover 301, and the mounting stud 304 is used to connect the paper feeding mounting plate 311, and the paper feeding mounting plate 311 is used to install the filter paper 310. The guide member 305 is arranged on the inner side of the filter paper 310, and plays a guiding role when the paper feeding structure 30 is pulled and connected to the detector housing 10.

[0077] See also Figure 4 , Figure 6 and Figure 7 In one embodiment of the present invention, the paper feeding mechanism 30 further includes a sealing ring 330. A sealing ring 330 is provided on a side of the paper feeding mechanism 30 close to the detector housing 10. The sealing ring 330 can be provided on the front cover plate 301. The sealing ring 330 serves to seal between the detector housing 10 and the paper feeding structure 30.

[0078] See also Figure 4 , Figure 6 and Figure 7 In one embodiment of the present invention, the moving assembly 320 includes a driving shaft 321 , a driving shaft nut 3210 , a driving motor 3211 , a driven shaft 322 and a driven shaft nut 3220 .

[0079] Specifically, the driving shaft nut 3210 is connected to the driving shaft 321 to connect the driving shaft 321 to the paper feeding installation plate 311, and the driven shaft nut is connected to the driven shaft 322 to connect the driven shaft 322 to the paper feeding installation plate 311, and the driving shaft 321 and the driven shaft 322 are rotatable. The output end of the driving motor 3211 is connected to the driving shaft 321 to drive the driving shaft 321 to rotate. The filter paper 310 is connected to the outside of the driving shaft 321 and the driven shaft 322. The driving motor 3211 can drive the driving shaft 321 to rotate, and the rotation of the driving shaft 321 can drive the filter paper 310 thereon to move, and the driven shaft 322 rotates with the movement of the filter paper 310, so that the driving motor 3211 can move the filter paper 310 at the air inlet pipe interface 120 to the detection end of the radiation detector 20.

[0080] See also Figure 4 , Figure 6 , Figure 7 and Fig. 9 In one embodiment of the present invention, the moving assembly 320 further includes a filter paper cylinder 323, a guide shaft 324, a counting shaft 325, a counting shaft pressing piece 3252 and a counting assembly.

[0081] Specifically, a filter paper cylinder 323 may be connected to the outside of the driving shaft 321, and a filter paper cylinder 323 may be connected to the outside of the driven shaft 322. The filter paper cylinder 323 of the driving shaft 321 and the filter paper cylinder of the driven shaft 322 may be sleeved with filter paper 310 to achieve the installation of the filter paper 310. The counting shaft 325 is arranged between the driving shaft 321 and the driven shaft 322 and is located on one side of the filter paper 310. The driving shaft 321, the driven shaft 322 and the counting shaft 325 rotate synchronously.

[0082] Specifically, the counting assembly can calculate the moving distance of the filter paper 310 based on the number of rotations of the counting shaft 325. For example, the counting assembly can include a gear cylinder 3251 and a photoelectric sensor 326, wherein the gear cylinder 3251 is sleeved and connected to the outer side of the counting shaft 325, and the photoelectric sensor 326 is arranged on one side of the counting shaft 325, and the detection end of the photoelectric sensor 326 faces the gear of the gear cylinder 3251. The counting shaft pressing piece 3252 is used to limit the counting shaft 325.

[0083] Specifically, inside the detector housing 10, the driving shaft 321 and the counting shaft 325 are located on a side close to the radiation detector 20, and the driven shaft 322 is located on a side close to the air inlet interface 120. The direction between the detection end of the radiation detector 20 and the air inlet interface 120 is recorded as the connecting direction, and the extending direction of the filter paper 310 is parallel to the connecting direction. Figure 6 As shown, the guide shaft 324 is arranged on a side close to the air intake pipe interface 120 , and the guide shaft 324 serves to turn the filter paper 310 , and the guide shaft 324 can also tighten the filter paper 310 to ensure the normal transmission of the filter paper 310 .

[0084] See also Figure 4 , Figure 6 , Figure 7 and Figure 8 In one embodiment of the present invention, the moving assembly 320 also includes a bearing 3221 , a damping seat 3222 , a driven shaft pressure plate 3223 , a damping cover 3224 , a damping pressure plate 3225 and a damping pad 3226 .

[0085] Specifically, the bearing 3221 is sleeved on the outside of the driven shaft 322, the damping seat 3222 is arranged at the top of the driven shaft 322, and the driven shaft pressure plate 3223 is arranged at the top of the driven shaft 322 to limit the driven shaft 322. The damping cover 3224 is arranged at the top of the damping seat 3222, and a damping pressure plate 3225 and a damping pad 3226 are arranged between the damping seat 3222 and the damping cover 3224. The damping pressure plate 3225 limits the damping seat 3222, and the damping pad 3226 is arranged at the top of the damping pressure plate 3225.

[0086] See also Fig.10 In one embodiment of the present invention, a sealing gasket 210 is provided at the bottom of the radiation detector 20, and the sealing gasket 210 can be connected to the detector interface 110, and the sealing gasket 210 plays a role in sealing between the radiation detector 20 and the detector housing 10. A detector inner sleeve 220 is provided at the top of the radiation detector 20, and the detector inner sleeve 220 plays a role in protecting the radiation detector 20.

[0087] Specifically, the radiation detector 20 may include a detector module, an electronic module, a cooling fan, a housing structure, and related connecting parts.

[0088] Among them, the detector module uses 4 22mm×22mm×10mm cadmium zinc telluride (CZT) detector modules. Each cadmium zinc telluride (CZT) detector module consists of 11×11, a total of 121 pixels, with a pixel size of 2mm, an overall size of 44mm×44mm×10mm, and a total of 484 pixels. For example, the pixel electrode structure is used to achieve single-stage charge sensitivity, and the energy resolution of the gamma-ray energy spectrum obtained from a single pixel electrode is significantly improved compared to the traditional flat electrode detector. In order to further improve the energy resolution of the detector module, the overall detector crystal is simulated and cut into several individual elements in three-dimensional space, and then the charge collection efficiency of each element is calibrated and corrected, thereby eliminating the difference in charge collection efficiency caused by carrier resurrection, material inhomogeneity, etc. The energy resolution of the detector module does not exceed 0.9% (Cs-137, 662keV).

[0089] Specifically, since the CZT detector module needs to dissipate heat, the shell structure is made of aluminum alloy, and heat sinks are installed around the detector module, which cooperates with the internal cooling fan to facilitate rapid heat dissipation. Designing metal protection structures around the CZT detector module not only facilitates the installation and fixation of the detector module, but also prevents the CZT detector module from being damaged during installation, transportation and use, thereby improving the reliability and service life of the CZT detector module.

[0090] Specifically, the cadmium zinc telluride (CZT) detector module can use an RJ45 network port to communicate data with the outside, and a 2-core LEMO connector can be used to power the cadmium zinc telluride (CZT) detector module.

[0091] See also Fig.11 In one embodiment of the present invention, the outer shielding body 410 includes a bottom shielding body 411 , a middle shielding body 412 and a top shielding body 413 .

[0092] Specifically, the bottom shield 411 and the middle shield 412 are annular, and the top shield 413 is cap-shaped. The bottom shield 411 is disposed on the outer wall of the detector housing 10, the middle shield 412 is coaxially connected to the bottom shield 411, and the top shield 413 is coaxially connected to the middle shield 412.

[0093] See also Fig.12 , Fig.13 and Fig.14 In one embodiment of the present invention, the bottom shield 411 may include a bottom shield bottom plate 4111 , a bottom shield partition 4113 , and a bottom shield handle 4114 .

[0094] Specifically, Fig.13 As shown, a bottom shield inner cavity 4112 may be formed between the bottom shield bottom plate 4111 and the bottom shield partition 4113, and a lead 4101 may be filled in the outer shell of the bottom shield inner cavity 4112. A bottom shield handle 4114 may be provided on the outer shell of the bottom shield inner cavity 4112. A ventilation hole 4100 may be opened on the outer shell of the bottom shield inner cavity 4112.

[0095] See also Fig.15 , Fig.16 and Fig.17 In one embodiment of the present invention, the middle shielding body 412 may include a middle shielding body bottom plate 4121, a middle shielding body partition plate 4122, a middle shielding body inner cavity 4123, a threaded sleeve 4124, a hexagon socket screw 4125, a threaded column 4126 and a middle shielding body handle 4127.

[0096] Specifically, a central shielding body inner cavity 4123 may be provided between the central shielding body bottom plate 4121 and the central shielding body partition plate 4122, and a shell outside the central shielding body inner cavity 4123 may be filled with lead 4101. A central shielding body handle 4127 may be provided on the shell outside the central shielding body inner cavity 4123. A ventilation hole 4100 may be provided on the shell outside the central shielding body inner cavity 4123.

[0097] Specifically, a threaded sleeve 4124 may be provided in the outer shell of the inner cavity 4123 of the middle shielding body, and the bottom and top of the threaded sleeve 4124 may be provided with hexagon socket screws 4125 and threaded columns 4126 respectively. The hexagon socket screws 4125 and threaded columns 4126 are used to connect the middle shielding body 412 with the bottom shielding body 411 and the top shielding body 413 respectively.

[0098] See also Fig.18 and Fig.19 In one embodiment of the present invention, the top shield 413 may include a top shield bottom plate 4131 and a top shield top 4132. A threading hole 4102 may be provided on the outer wall of the top shield 413, and the threading hole 4102 may be used to connect the radiation detector 20 to a power source.

[0099] See also Fig. 20 and Fig.21 In one embodiment of the present invention, the internal shielding body 420 may include an internal shielding body bottom plate 421 and an internal shielding body top plate 422 . The internal shielding body bottom plate 421 faces the inside of the detector housing 10 , and the internal shielding body top plate 422 faces the filter paper 310 .

[0100] See also Fig. 22 In one embodiment of the present invention, the monitoring device for aerosol nuclide activity in a nuclear facility may further include a differential pressure meter 510 , a first pipeline 520 and a second pipeline 530 .

[0101] Specifically, the differential pressure gauge 510 is connected to the air intake pipe 121 through the first pipe 420, and the differential pressure gauge 510 is connected to the exhaust pipe 130 through the second pipe 530. The differential pressure gauge 510 forms a differential pressure signal from the air pressure difference between the first pipe 520 and the second pipe 530, and transmits the differential pressure signal to the control end of the drive motor 3211. When the air pressure difference reaches the limit set by the user, the drive motor 3211 can move the filter paper 310 at the air intake pipe interface 120 to the detection end of the radiation detector 20 under the control of the differential pressure signal.

[0102] In summary, the monitoring device for aerosol nuclide activity in nuclear facilities disclosed in the present invention can timely obtain the change of aerosol radionuclide activity concentration in airborne effluent. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0103] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A monitoring device for aerosol nuclide activity in a nuclear facility, characterized in that: include: The detector housing has an outer wall provided with a detector interface, an air intake pipe interface and an exhaust pipe interface, wherein the air intake pipe interface is externally connected to an air intake pipeline, and the exhaust pipe interface is externally connected to an exhaust pipeline; A radiation detector, disposed at the detector interface; The paper feeding mechanism is arranged inside the detector housing and includes: Filter paper, extending between the detection end of the radiation detector and the air inlet pipe interface; a moving component, an output end of which is connected to the filter paper; and A shielding body assembly, comprising an external shielding body and an internal shielding body, wherein the external shielding body is sleeved on the outside of the radiation detector, the internal shielding body is arranged inside the detector housing, and the filter paper is located between the detection end of the radiation detector and the internal shielding body; Wherein, the paper feeding mechanism is used to move the filter paper at the air inlet pipe interface to the detection end of the radiation detector.

2. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 1, characterized in that: The monitoring device further comprises a sealing ring. The paper feeding mechanism is connected in a pull-out manner in the detector housing. A sealing ring is arranged on one side of the paper feeding structure close to the detector housing.

3. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 1, characterized in that: A sealing gasket is arranged at the bottom of the radiation detector, and the sealing gasket is connected to the detector interface.

4. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 1, characterized in that: The moving assembly includes a driving motor, a driving shaft, a driven shaft, and a filter paper cylinder. The driving shaft is connected to the output end of the driving motor. The filter paper cylinder is respectively sleeved on the driving shaft and the driven shaft. The filter paper is connected to the filter paper cylinder of the driving shaft and the filter paper cylinder of the driven shaft.

5. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 4, characterized in that: The paper feeding mechanism further comprises a counting shaft and a counting assembly, wherein the counting shaft is arranged between the driving shaft and the driven shaft and is located on one side of the filter paper, and the driving shaft, the driven shaft and the counting shaft rotate synchronously; The counting component calculates the moving distance of the filter paper based on the number of rotations of the counting shaft.

6. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 5, characterized in that: The counting assembly includes a gear cylinder and a photoelectric sensor. The gear cylinder is sleeved and connected to the outside of the counting shaft. The photoelectric sensor is arranged on one side of the counting shaft. The detection end of the photoelectric sensor faces the gear of the gear cylinder.

7. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 5 or 6, characterized in that: Inside the detector housing, the driving shaft and the counting shaft are located on a side close to the radiation detector, and the driven shaft is located on a side close to the air intake pipe interface.

8. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 5 or 6, characterized in that: The direction between the detection end of the radiation detector and the air inlet pipe interface is recorded as the connection direction, and the extension direction of the filter paper is parallel to the connection direction.

9. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 4, characterized in that: The paper feeding mechanism further includes a pressure difference component, the pressure difference component includes a pressure difference gauge, the pressure difference gauge is connected to the air intake pipe through a first pipe, and the pressure difference gauge is connected to the exhaust pipe through a second pipe; The differential pressure gauge generates a differential pressure signal when the air pressure difference between the first pipe and the second pipe reaches a preset threshold value, and the drive motor moves the filter paper at the air inlet pipe interface to the detection end of the radiation detector according to the differential pressure signal.

10. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 1, characterized in that: The external shielding body comprises a bottom shielding body, a middle shielding body and a top shielding body, the bottom shielding body and the middle shielding body are ring-shaped, and the top shielding body is cap-shaped; The bottom shielding body is arranged on the outer wall of the detector housing, the middle shielding body is connected to the bottom shielding body, and the top shielding body is connected to the middle shielding body.

11. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 10, characterized in that: The ventilation holes are provided on the side walls of the bottom shielding body and the middle shielding body, and the wire threading holes are provided on the side walls of the top shielding body for connecting the radiation detector to the outside with wires.

12. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 10, characterized in that: The bottom shield, the middle shield and the top shield are filled with lead.

13. The monitoring device for aerosol nuclide activity in nuclear facilities according to claim 1, characterized in that: The detector interface and the air inlet pipe interface are opened on the top of the detector housing, and the exhaust pipe interface is opened on the side wall of the detector housing.

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