Marine radionuclide monitor

Abstract

The utility model is suitable for the field of nuclide detection, and discloses a marine radionuclide monitor, which comprises a nuclide detection probe and a signal processing unit, the nuclide detection probe comprises a probe shell, a scintillator for detecting a gamma ray signal of a water body, a photomultiplier and a shock isolation assembly, the scintillator for detecting the gamma ray signal of the water body and the photomultiplier are connected with the shock isolation assembly and are arranged in the probe shell, and the photomultiplier is electrically connected with the signal processing unit; the signal processing unit comprises a case shell, a detection plate and a power panel, the detection plate and the power panel are arranged in the case shell, the detection plate at least comprises a passive efficiency scale module, and automatic efficiency scale is carried out through the passive efficiency scale module; and the power panel supplies power to the nuclide detection probe and the signal processing unit.

Description

Technical Field

[0001] The utility model relates to the field of nuclide detection, in particular to a marine radionuclide monitor. Background Art

[0002] Most nuclear power plants under construction and currently in operation, both domestically and internationally, are located along the coast. Exceeding standards for radioactive effluent from nuclear power plants poses a direct threat to the marine ecosystem and the health of surrounding residents, placing significant emphasis on monitoring marine radioactive contamination. Marine radioactive contamination has the characteristics of wide spread and rapid migration, making rapid, large-scale monitoring of marine environmental radioactivity crucial.

[0003] Currently, China primarily monitors marine environmental radioactivity using manual sampling and analysis. Workers travel to target waters by ship or boat to collect samples, which are then brought back to the laboratory for analysis. This traditional approach is labor-intensive, time-consuming, and inefficient, making it impossible to obtain timely and accurate data on the distribution of marine radioactivity, and it is also unable to monitor short-lived radionuclides. Furthermore, my country's vast maritime territory and complex environment make comprehensive monitoring of the marine environment difficult. Furthermore, due to the large number and wide distribution of monitoring points, the entire process is labor-intensive, with a large number of samples, long sampling and analysis times, and poor timeliness. Depending on the monitoring area, a single round of data monitoring can take days to months, making it impossible to obtain highly accurate radioactivity distribution data in a timely manner. Furthermore, prolonged floating in the ocean can easily lead to water ingress and electronic component failure. Consequently, there is a lack of a detector that can adapt to harsh environments and detect radionuclides in marine waters over long periods of time. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a marine radionuclide monitor, aiming to solve the problem in the prior art that it cannot adapt to long-term detection in harsh environments.

[0005] The technical solution adopted by the utility model to solve its technical problems includes: a nuclide detection probe and a signal processing unit; the nuclide detection probe includes a probe housing, a scintillator for detecting the gamma-ray signal of a water body, a photomultiplier tube and a seismic isolation component, the scintillator and photomultiplier tube for detecting the gamma-ray signal of the water body are connected to the seismic isolation component and arranged in the probe housing, and the photomultiplier tube is electrically connected to the signal processing unit; the signal processing unit includes a chassis housing, a detection board and a power supply board, the detection board and the power supply board are arranged in the chassis housing, the detection board includes at least a passive efficiency calibration module, and automatic efficiency calibration is performed through the passive efficiency calibration module; the power supply board provides power for the nuclide detection probe and the signal processing unit.

[0006] In one embodiment, the seismic isolation assembly includes an upper shock-absorbing sleeve, a lower shock-absorbing sleeve and an elastic abutment. The upper shock-absorbing sleeve and the lower shock-absorbing sleeve wrap the scintillator and the photomultiplier tube for detecting the gamma-ray signal of the water body and place them in the probe housing. The elastic abutment is arranged in the probe housing. The lower shock-absorbing sleeve and the photomultiplier tube abut against the elastic abutment and are pushed to one end of the probe housing.

[0007] In one embodiment, the elastic abutment includes an inner spring and an outer spring, the inner spring and the outer spring are connected to the probe housing, the other end of the inner spring is connected to the photomultiplier tube, and the outer spring is connected to the lower shock-absorbing sleeve.

[0008] In one embodiment, the seismic isolation assembly is further provided with a phototube seat and a spring top ring, the phototube seat is connected to one end of the scintillator of the photomultiplier tube away from the gamma-ray signal of the detected water body, and the spring top ring is abutted against the phototube seat by the inner spring.

[0009] In one embodiment, the power board is further provided with a status monitoring and self-test module for real-time monitoring of the equipment, judging the system status and promptly giving an alarm for faults.

[0010] In one embodiment, the detection board includes a high-voltage module, an input module and an operation module. The electrical signal generated by the photomultiplier tube passes through the high-voltage module and the input module in sequence. The input module converts the electrical signal into data, and the data is processed by the operation module.

[0011] In one embodiment, the scintillator for detecting the gamma-ray signal of water body is LaBr3 crystal.

[0012] In one embodiment, an electromagnetic compatibility protection module is provided on the power board, and the electromagnetic compatibility protection module provides electromagnetic protection for the entire power board.

[0013] In one embodiment, a communication module is provided on the power board, and the information obtained by the detection board is transmitted to the ground data center through the communication module.

[0014] In one embodiment, the signal processing unit (400) uses an ARM chip.

[0015] The implementation of the utility model has the following beneficial effects: the nuclide detection probe includes a scintillator for detecting the gamma-ray signal of the water body and a photomultiplier tube for measuring the radiation signal. A seismic isolation component is arranged in the middle. The seismic isolation component is wrapped around the crystal and, together with the spring, realizes buffering and vibration reduction, protecting the probe from damage under long-term ocean surges, debris impacts, and fish gnawing conditions. The geometric relationship between the detector and the source is drawn through the drawing function of the passive efficiency calibration module, and automatic efficiency calibration is performed according to the built-in characterization file to determine the experimental work of the nuclear radiation detector in recording the incident particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can derive other relevant drawings based on these drawings without inventive effort. In the drawings:

[0017] Figure 1 This is a structural diagram of a probe of a marine radionuclide monitor in one embodiment of the present utility model;

[0018] Figure 2 It is a right side view of a marine radionuclide monitor in one embodiment of the utility model.

[0019] Figure annotation

[0020] 100. Shell; 200. Beidou satellite communication module; 210. Solar panel; 300. Nuclide detection probe; 310. Probe housing; 320. Front end cover; 330. Upper shock-absorbing sleeve; 340. Sealing ring; 350. Scintillator for detecting gamma-ray signals in water bodies; 360. Photomultiplier tube; 370. Photoelectric tube holder; 380. Lower shock-absorbing sleeve; 390. Spring top ring; 391. Inner spring; 392. Outer spring; 400. Signal processing unit. DETAILED DESCRIPTION

[0021] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific embodiments of the present invention are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the directions or positional relationships indicated by "front", "back", "up", "down", "left", "right", "longitudinal", "horizontal", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", etc. are based on the directions or positional relationships shown in the accompanying drawings and are constructed and operated in specific directions. They are only for the convenience of describing the present technical solution and do not indicate that the devices or components referred to must have specific directions. Therefore, they should not be understood as limiting the present invention.

[0022] It should also be noted that, unless otherwise clearly specified and limited, terms such as "installed", "connected", "connected", "fixed", and "set" should be understood in a broad sense. For example, they can be fixedly connected, detachably connected, or integrated; they can be mechanically connected or electrically connected; they can be directly connected or indirectly connected through an intermediate medium, and they can be internal connections between two elements or interactions between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located on the other element, or there may be one or more intervening elements. The terms "first", "second", and "third" are only used to facilitate the description of the present technical solution and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", and "third" can explicitly or implicitly include one or more of these features. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0023] Figures 1 to 2 A marine radionuclide monitor in an embodiment of the present invention is shown. The marine radionuclide monitor can be used for detecting marine radionuclides, and may include a radionuclide detection probe and a signal processing unit; the radionuclide detection probe includes a probe housing, a scintillator for detecting γ-ray signals of water bodies, a photomultiplier tube and a seismic isolation assembly, the scintillator and photomultiplier tube for detecting γ-ray signals of water bodies are connected to the seismic isolation assembly and arranged in the probe housing, and the photomultiplier tube is electrically connected to the signal processing unit; the signal processing unit includes a chassis housing, a detection board and a power supply board, the detection board and the power supply board are arranged in the chassis housing, the detection board includes a passive efficiency calibration module, the geometric relationship between the detector and the source is drawn by the passive efficiency calibration module's built-in drawing function, and automatic efficiency calibration is performed according to the built-in characterization file; the power supply board provides power for the radionuclide detection probe and the signal processing unit. The radionuclide detection probe includes a scintillator for detecting gamma-ray signals in water bodies and a photomultiplier tube for measuring radiation signals. A seismic isolation component is set in the middle. The seismic isolation component is wrapped around the crystal and, together with the spring, provides buffering and vibration reduction, protecting the probe from damage under long-term conditions such as ocean surges, debris impacts, and fish gnawing. The passive efficiency calibration module has a built-in drawing function to draw the geometric relationship between the detector and the source, and automatic efficiency calibration is performed according to the built-in characterization file to determine the experimental work of the nuclear radiation detector's efficiency in recording incident particles.

[0024] It can be understood that the probe is composed of a scintillator 350 for detecting the gamma-ray signal of the water body and a photomultiplier tube 360. After the gamma radiation photons enter the sensitive volume of the crystal for detecting the gamma-ray signal of the water body, different numbers of fluorescent photons are emitted according to the energy intensity of the incident gamma photons. The fluorescent photons generate photoelectrons through the photomultiplier tube 360 ​​and multiply the photoelectrons, and finally output them to the signal processing unit.

[0025] The passive efficiency calibration module built into the detection board has a built-in characterization file that records the attenuation curves of different energy rays in different materials. The module's built-in drawing function is used to draw the geometric relationship between the detector and the source and input the source's composition and density. The module divides the source into a large number of small volume sources that can be regarded as point sources. Considering the attenuation on the path between the point source and the detector and the self-absorption effect of the source, the efficiency of all point sources with respect to the detector is integrated to obtain the detector's detection efficiency, thereby realizing passive efficiency calibration. Knowing the efficiency scale of the detector, the detected data can be converted into nuclide activity. Activity refers to the average number of atomic decays per second.

[0026] Figure 1 In one embodiment, a scintillator for detecting gamma-ray signals from water bodies may include a LaBr3 crystal. Compared to gas detectors and traditional NaI scintillators, the scintillator 350 for detecting gamma-ray signals from water bodies has higher detection efficiency, better energy resolution, and faster time response. This allows for more precise nuclide differentiation, a lower activity detection limit, faster measurement speed, and a wide counting measurement range. The scintillator 350 for detecting gamma-ray signals from water bodies has a built-in 1468keV La peak that can be passively stabilized to control temperature drift, ensuring long-term stable operation of the device. Compared to semiconductor detectors, scintillator detectors do not require cryogenic conditions, are more economical, and have a longer service life.

[0027] Figure 1 It is shown that the seismic isolation assembly may include an upper shock-absorbing sleeve 330, a lower shock-absorbing sleeve and an elastic abutment in one embodiment. The upper shock-absorbing sleeve 330 and the lower shock-absorbing sleeve 380 wrap the scintillator 350 and the photomultiplier tube 360 ​​for detecting the gamma-ray signal of the water body and place them in the probe housing 310. The elastic abutment is set in the probe housing 310. The lower shock-absorbing sleeve 380 and the photomultiplier tube 360 ​​abut against the elastic abutment and are pushed to one end of the probe housing 310.

[0028] Figure 1It is shown that the elastic abutment may include an inner spring 391 and an outer spring 392 in one embodiment. The inner spring 391 and the outer spring 392 are connected to the probe housing 310. The other end of the inner spring 391 is connected to the photomultiplier tube 360. The outer spring 392 is connected to the lower shock-absorbing sleeve 380. The separation of the inner spring 391 and the outer spring 392 can simultaneously absorb the shock of the lower shock-absorbing sleeve 380 and the photomultiplier tube 360, thereby avoiding the situation where all shock-absorbing structures fail if one of them fails.

[0029] Figure 1 It is shown that the seismic isolation assembly may include a phototube holder 370 and a spring top ring 390 in one embodiment. The phototube holder 370 is connected to one end of the scintillator 350 of the photomultiplier tube 360 ​​away from the gamma-ray signal of the water body for detecting the gamma-ray signal. The spring top ring 390 is abutted against the phototube holder 370 by the inner spring 391 to avoid direct contact between the spring and the photomultiplier tube 360, thereby improving the service life of the photomultiplier tube 360.

[0030] Figure 1 In one embodiment, the upper shock-absorbing sleeve 330 and the lower shock-absorbing sleeve 380 may include a sealing ring 340 on the outer wall of each of the upper shock-absorbing sleeve 330 and the lower shock-absorbing sleeve 380. The sealing ring 340 prevents water from entering the photomultiplier tube 360 ​​and affecting signal generation.

[0031] As can be understood, the housing houses a crystal and a photoelectric tube holder 370 for measuring radiation signals. The central portion is equipped with an upper isolation sleeve 330, a lower isolation sleeve 380, an inner spring 391, and an outer spring 392. The upper and lower isolation sleeves 330 and 380 wrap around the crystal and, together with the springs, provide vibration damping, protecting the probe from damage caused by prolonged ocean surges, debris impacts, and fish grazing. The ends of the probe housing 310 are sealed by a sealing ring 340 and a sealing end cap. The housing 310 has a waterproof rating exceeding IP68, ensuring the entire radionuclide monitor operates at depths greater than 100 meters underwater. The housing is constructed of 316L stainless steel, offering excellent structural performance, strong corrosion resistance, and a smooth surface. This 316L material ensures the radionuclide monitor can withstand high pressures at depths of 100 meters underwater, protecting it from corrosion from seawater, damage from fish grazing, and minimizing surface contamination during long-term operation in marine environments.

[0032] Figure 2The power board shown in one embodiment may include a status monitoring and self-test module on the power board that monitors the equipment in real time, determines the system status and promptly alarms for faults. The status monitoring and self-test module monitors the equipment in real time, determines the system status and promptly alarms for faults to ensure long-term stable operation of the system. The status monitoring module compares the high-voltage power supply voltage, power supply voltage, temperature and current collected by the system with the set threshold value. The self-test module sends a self-test pulse and compares the number of self-test pulses with the count after circuit processing. If the above-mentioned monitored parameters exceed the threshold range, the alarm signal and characteristic fault code are output to the outside through the communication module and transmitted back to the ground data center to ensure the normal operation of the power board and the authenticity and reliability of the detection data.

[0033] Figure 1 It is shown that the probe housing 310 may include a front end cover 320 provided near the probe housing 310 at the scintillator 350 for detecting the gamma-ray signal of the water body. The front end cover 320 limits the scintillator 350 for detecting the gamma-ray signal of the water body. The front end cover 320 axially limits the scintillator 350 for detecting the gamma-ray signal of the water body. When needed, the front end cover 320 can be opened to allow the scintillator 350 for detecting the gamma-ray signal of the water body to directly contact the seawater.

[0034] Figure 2 The detection board may include a high-voltage module, an input module and an operation module in one embodiment. The electrical signal generated by the photomultiplier tube passes through the high-voltage module and the input module in sequence. The input module converts the electrical signal into data, and the data is processed by the operation module.

[0035] As can be understood, the high-voltage module provides the electric field required for directional electron drift during the electron multiplication process. The multiplied electron beam is collected at the anode to form an intrinsic current and output a pulse signal. The pulse signal is initially amplified and filtered by the input module to produce a peak pulse that approximates a Gaussian function. The pulse is then sampled and converted to digital by a high-speed ADC to produce a digital pulse signal. The digital pulse signal is read by the FPGA in the data acquisition and cache module and processed through digital filtering to extract the amplitude, thereby obtaining the pulse amplitude distribution spectrum.

[0036] Figure 2In one embodiment, a power board is shown as including an electromagnetic compatibility (EMC) protection module. This module provides electromagnetic protection for the entire power board, reducing signal interference and electromagnetic shielding within a specific area of ​​space to attenuate the field strength caused by certain sources. In most cases, the shield can be made of metals such as copper, aluminum, and steel. However, for constant and extremely low-frequency magnetic fields, materials such as ferrite can also be used as a shield. Electromagnetic noise or interference often occurs within a system or between different systems, causing system performance degradation. Therefore, a specific area is shielded from the influence of external power lines and magnetic lines of force.

[0037] Figure 2 It is shown that the power board may include a communication module in one embodiment. The information obtained by the detection board is transmitted to the ground data center through the communication module. The communication module includes a 485 communication module and a satellite communication module 200. The energy spectrum information and nuclide information after calculation and processing are transmitted through the 485 communication module and the satellite communication module 200 to transmit the data back to the ground data center.

[0038] Figure 2 It is shown that the signal processing unit 400 may include an ARM chip in one embodiment. The ARM chip has functions such as peak search, peak stabilization, nuclide identification, background subtraction, and passive efficiency calibration for energy spectrum data.

[0039] It can be understood that the above embodiments only express the preferred implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the patent scope of the present invention. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can be made, all of which fall within the scope of protection of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of coverage of the claims of the present invention.

Claims

1. A marine radionuclide monitor, characterized in that: include: a nuclide detection probe (300) and a signal processing unit (400); The nuclide detection probe (300) comprises a probe housing (310), a scintillator (350) for detecting gamma-ray signals of a water body, a photomultiplier tube (360), and a seismic isolation assembly. The scintillator (350) for detecting gamma-ray signals of a water body and the photomultiplier tube (360) are connected to the seismic isolation assembly and arranged in the probe housing (310), and the photomultiplier tube is electrically connected to the signal processing unit. The signal processing unit (400) comprises a chassis shell, a detection board, and a power supply board. The detection board and the power supply board are arranged in the chassis shell. The detection board at least comprises a passive efficiency calibration module, and automatic efficiency calibration is performed through the passive efficiency calibration module. The power supply board provides power for the nuclide detection probe (300) and the signal processing unit (400).

2. A marine radionuclide monitor according to claim 1, characterized in that: The seismic isolation assembly comprises an upper shock-absorbing sleeve (330), a lower shock-absorbing sleeve (380) and an elastic abutment member. The upper shock-absorbing sleeve (330) and the lower shock-absorbing sleeve (380) wrap the scintillator (350) and the photomultiplier tube (360) for detecting the gamma-ray signal of the water body and place them into a probe housing (310). The elastic abutment member is arranged in the probe housing (310). The lower shock-absorbing sleeve (380) and the photomultiplier tube (360) abut against the elastic abutment member and are pushed to one end of the probe housing (310).

3. A marine radionuclide monitor according to claim 2, characterized in that: The elastic abutment member includes an inner spring (391) and an outer spring (392), wherein the inner spring (391) and the outer spring (392) are connected to the probe housing (310), the other end of the inner spring (391) is connected to the photomultiplier tube (360), and the outer spring (392) is connected to the lower shock-absorbing sleeve.

4. A marine radionuclide monitor according to claim 3, characterized in that: The seismic isolation assembly is further provided with a phototube holder (370) and a spring top ring (390). The phototube holder (370) is connected to one end of the photomultiplier tube (360) away from the scintillator (350) for detecting the gamma-ray signal of the water body, and the spring top ring (390) is abutted against the phototube holder (370) by the inner spring (391).

5. The marine radionuclide monitor according to claim 1, characterized in that: The power board is also provided with a status monitoring and self-test module for real-time monitoring of the equipment, judging the system status and promptly giving an alarm for faults.

6. The marine radionuclide monitor according to claim 1, characterized in that: The detection board comprises a high-voltage module, an input module and a calculation module. The electrical signal generated by the photomultiplier tube (360) passes through the high-voltage module and the input module in sequence. The input module converts the electrical signal into data, and the data is processed by the calculation module.

7. The marine radionuclide monitor according to claim 1, characterized in that: The scintillator (350) for detecting the gamma-ray signal of the water body adopts LaBr3 crystal.

8. The marine radionuclide monitor according to claim 1, characterized in that: The power board is provided with an electromagnetic compatibility protection module, and the electromagnetic compatibility protection module performs electromagnetic protection on the entire power board.

9. The marine radionuclide monitor according to claim 1, characterized in that: The power board is provided with a communication module, and the information obtained by the detection board is transmitted to the ground data center through the communication module.

10. The marine radionuclide monitor according to claim 1, characterized in that: The signal processing unit (400) adopts an ARM chip.

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