Nuclear power radioactive liquid effluent measuring device

Abstract

The invention discloses a nuclear power radioactive liquid effluent measuring device. The nuclear power radioactive liquid effluent measuring device comprises a detection assembly installed on a pipeline, an external shielding layer wrapping the periphery of the detection assembly and a data processing system. The detection assembly comprises a plurality of CZT detectors which are arranged at intervals in the circumferential direction of the pipeline; and the data processing system is connected with the detection assembly, receives the detection signal sent by the detection assembly, analyzes and processes the detection signal, identifies the radionuclide in the nuclear power radioactive liquid effluent and measures the radioactive activity of the radionuclide. According to the nuclear power radioactive liquid effluent measuring device, the CZT detectors are arranged on the periphery of the pipeline, the nuclear power radioactive liquid effluent in the pipeline can be monitored in an all-around mode, the radioactive activity of various radionuclides in the nuclear power radioactive liquid effluent can be accurately distinguished and measured, and a powerful guarantee is provided for safety management of the nuclear power plant radioactive liquid effluent.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power radioactive substance monitoring, and particularly to a measuring device for nuclear power radioactive liquid effluents. Background Art

[0002] During the operation of nuclear power plants, it is inevitable to generate some radioactive liquid effluents. The management and monitoring of radioactive liquid effluents are important links to ensure environmental safety and public health. Under normal and abnormal operating conditions, nuclear power plants may generate different types and concentrations of radioactive liquid effluents, which contain various radioactive nuclides, such as tritium (3H), carbon-14 ( 14 C), silver-110m ( 110m Ag), cobalt-58 ( 58 Co), cobalt-60 ( 60 Co), iodine-131 ( 131 I), cesium-134 ( 134 Cs), cesium-137 ( 137 Cs), manganese-54 ( 54 Mn), antimony-124 ( 124 Sb), iron-59 ( 59 Fe), and ruthenium-106 ( 106 Ru), etc. If these radioactive substances are discharged without effective monitoring and control, they will cause serious harm to the environment and human health. Therefore, accurately and real-time monitoring the radioactive levels of these radioactive liquid effluents is an important measure to ensure the safe operation of nuclear power plants.

[0003] The existing radioactive liquid effluent monitoring technologies mainly include two methods: laboratory analysis and online monitoring. Although the laboratory analysis method can provide relatively accurate results, due to its complex process and long time consumption, it cannot meet the requirements of real-time monitoring. The online monitoring technology can provide continuous monitoring data, but the traditional online monitoring equipment has low sensitivity, long response time, and limitations in multi-nuclide identification. The existing online monitoring technologies mainly rely on scintillation detectors and semiconductor detectors, such as sodium iodide (NaI) detectors and high-purity germanium (HPGe) detectors, etc. However, scintillation detectors are poor in energy resolution and sensitivity and are difficult to distinguish multiple nuclides; although high-purity germanium detectors have high energy resolution, their operation is complex, the cost is high, and they require cryogenic cooling, which limits their popularization in practical applications. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an improved measuring device for nuclear power radioactive liquid effluents.

[0005] The technical solution adopted by the present invention to solve its technical problems is: to provide a measuring device for nuclear power radioactive liquid effluent, including a detection component installed on a pipeline, an external shielding layer covering the outer periphery of the detection component, and a data processing system;

[0006] The detection component includes a plurality of CZT detectors arranged at intervals along the circumferential direction of the pipeline and attached to the pipeline;

[0007] The data processing system is connected to the detection component, receives the detection signals sent by the detection component, analyzes and processes them, identifies the radionuclides in the nuclear power radioactive liquid effluent, and measures the radioactivity of the radionuclides.

[0008] Preferably, the detection component includes at least eight of the CZT detectors.

[0009] Preferably, the external shielding layer includes a lead shielding layer and a tungsten alloy shielding layer stacked inside and outside.

[0010] Preferably, the thickness of the lead shielding layer is 5 cm, and the thickness of the tungsten alloy shielding layer is 3 cm.

[0011] Preferably, the detection component further includes a detector bracket, the CZT detector is fixed inside the detector bracket, and is positioned on the outer periphery of the pipeline through the detector bracket.

[0012] Preferably, the detector bracket is made of a low-background radiation material, including at least one of polyethylene and Teflon.

[0013] Preferably, the measuring device for nuclear power radioactive liquid effluent further includes an internal shielding layer provided inside the detection component.

[0014] Preferably, the internal shielding layer is made of polyethylene material.

[0015] Preferably, the data processing system includes a data acquisition module for acquiring the detection signals of the CZT detectors, a data analysis module for analyzing and processing the detection signals, and a data transmission module connected between the data acquisition module and the data analysis module.

[0016] Preferably, the measuring device for nuclear power radioactive liquid effluent further includes an electric control system connected between the data processing system and the detection component. The electric control system includes a high-voltage power supply module, a signal processing module, and a control module; the high-voltage power supply module provides a stable high-voltage power supply for the CZT detectors; the signal processing module performs pre-amplification, shaping, and digitization processing on the pulse signals output by the CZT detectors, and sends the data obtained after processing to the data processing system; the control module is connected to the high-voltage power supply module and the signal processing module.

[0017] Advantages of the present invention: By arranging the CZT detector around the outer periphery of the pipeline, it can comprehensively monitor the radioactive liquid effluent in the pipeline in nuclear power, accurately distinguish and measure the radioactivity of various radionuclides therein, and provide a strong guarantee for the safety management of radioactive liquid effluent in nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0019] Figure 1 is a schematic structural diagram of a device for measuring radioactive liquid effluent in nuclear power on a pipeline according to an embodiment of the present invention;

[0020] Figure 2 is Figure 1 right view of. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] For a clearer understanding of the technical features, objectives, and effects of the present invention, the specific embodiments of the present invention will now be described in detail with reference to the drawings.

[0022] The device for measuring radioactive liquid effluent in nuclear power of the present invention is used to measure the radionuclides in the radioactive liquid effluent in nuclear power to identify the radionuclides and measure the radioactivity of the radionuclides.

[0023] The device for measuring radioactive liquid effluent in nuclear power of the present invention can be installed on a pipeline, which includes but is not limited to a discharge pipeline for discharging radioactive liquid effluent in nuclear power, a transport pipeline for transporting radioactive liquid effluent in nuclear power, a sampling pipeline, etc.

[0024] As Figure 1 , Figure 2 shown, the device for measuring radioactive liquid effluent in nuclear power according to an embodiment of the present invention may include a detection component, an external shielding layer 20, an electronic control system, and a data processing system.

[0025] The detection component is installed on the pipeline 100 and is used to detect the radioactive liquid effluent flowing in the pipeline 100. The external shielding layer 20 is coated on the outer periphery of the detection component and also on the outside of the pipeline 100, and can effectively block environmental radiation and secondary radiation. The data processing system is connected to the detection component, receives the detection signal sent by the detection component, and performs analysis and processing to identify the radionuclides in the radioactive liquid effluent in nuclear power and measure the radioactivity of the radionuclides.

[0026] Specifically, the detection component includes a plurality of CZT detectors 10, which are arranged at intervals along the circumferential direction of the pipeline 100 and are attached to the pipeline 100, so as to realize 360° all-round monitoring of the radioactivity level of the nuclear power radioactive liquid effluent in the pipeline 100.

[0027] The CZT detector (cadmium zinc telluride detector) 10, as a new type of semiconductor detector, has the advantages of high energy resolution, high sensitivity and working at room temperature. The energy resolution of the CZT detector 10 is usually 2.0% (at 662 keV), and it can detect energy changes as low as a few hundred eV; it can effectively overcome the shortcomings of traditional detectors. The CZT detector 10 has excellent detection performance for γ-rays and X-rays, can work at room temperature, and does not require liquid nitrogen cooling, with simple operation and low maintenance cost. Therefore, the CZT detector 10 has broad application prospects in the field of radioactive monitoring.

[0028] As an option, the CZT detector 10 can be selected but not limited to the Amptek XR-100T-CZT detector.

[0029] The size of the CZT detector 10 can be but not limited to 1 cm 3 .

[0030] To better achieve 360° all-round monitoring, the detection component preferably includes at least eight CZT detectors 10. The uniform arrangement at intervals on the outer periphery of the pipeline 100 enables each azimuth on the pipeline 100 to have a CZT detector 10. The more the number of CZT detectors 10 on the outer periphery of the pipeline 100, the denser the arrangement, and the better the uniformity in all directions.

[0031] In the present invention, by arranging the CZT detector 10 on the pipeline 100, the radioactivity of various radionuclides in the nuclear power radioactive liquid effluent in the pipeline can be accurately distinguished and measured.

[0032] Since each CZT detector 10 is independent, in order to uniformly arrange and fix a plurality of CZT detectors 10 on the outer periphery of the pipeline 100, the detection component further includes a detector bracket 30. A plurality of CZT detectors 10 are arranged and fixed in the detector bracket 30 at a predetermined interval, and are positioned on the outer periphery of the pipeline 100 through the detector bracket 30, and each CZT detector 10 is closely attached to the surface of the pipeline 100.

[0033] The detector bracket 30 can be in a ring structure, and the diameter is correspondingly set according to the outer diameter of the pipeline 100. The detector bracket 30 can further be installed on the outer periphery of the pipeline 100 by sleeving, or can also be installed on the outer periphery of the pipeline 100 by an opening and closing method.

[0034] The detector bracket 30 is made of low-background radiation materials to reduce the interference of environmental radiation on the measurement results. The low-background radiation materials include at least one of polyethylene and Teflon. Polyethylene has good mechanical properties and corrosion resistance, and Teflon has good high-temperature resistance and radiation resistance. The combination of the two can effectively improve the stability and durability of the detector bracket 30. Therefore, it is preferably made of polyethylene and Teflon to form the detector bracket 30.

[0035] The external shielding layer 20 is coated on the outer periphery of the pipeline 100 and the detection component, and can effectively block environmental radiation and secondary radiation. In one embodiment, the external shielding layer 20 includes a lead shielding layer and a tungsten alloy shielding layer stacked inside and outside. Lead and tungsten alloy have high density and good radiation shielding performance, which can significantly improve the shielding effect.

[0036] As an option, the thickness of the lead shielding layer is greater than that of the tungsten alloy shielding layer. For example, the thickness of the lead shielding layer is 5 cm, and the thickness of the tungsten alloy shielding layer is 3 cm.

[0037] To further reduce the influence of environmental radiation, in one embodiment, the nuclear power radioactive liquid effluent measuring device further includes an internal shielding layer 40, which is arranged inside the detection component and cooperates with the external shielding layer 20 to cover the inside and outside of the detection component. The internal shielding layer 40 can also be coated on the outer periphery of the pipeline 100 at the same time; in this regard, the internal shielding layer 40 is also provided with a plurality of holes for the CZT detector 10 to be embedded and closely attached to the surface of the pipeline 100.

[0038] The internal shielding layer 40 is made of polyethylene material. Polyethylene has low density and good performance of absorbing secondary radiation, which can further improve the measurement accuracy. The thickness of the internal shielding layer 40 is less than that of the external shielding layer 20, and the specific thickness can be but is not limited to 2 cm.

[0039] The electronic control system is connected between the data processing system and the detection component, and further may include a high-voltage power supply module, a signal processing module and a control module.

[0040] The high-voltage power supply module is respectively connected to the CZT detector 10 and the control module, and provides a stable high-voltage power supply for the CZT detector 10 to ensure the normal operation of the CZT detector 10. In one embodiment, the high-voltage power supply module can select the high-voltage power supply module with the model of Ortec556, and the high-voltage range is 0 - 1000V. The Ortec556 high-voltage power supply module has high stability and precise voltage control ability, which can provide a stable working voltage for the CZT detector 10 and ensure the reliability of the measurement.

[0041] The signal processing module is respectively connected to the CZT detector 10 and the control module, pre-amplifies, shapes, and digitizes the pulse signal output by the CZT detector 10, and sends the processed data to the data processing system. In one embodiment, the signal processing module can adopt an Ortec 672 shape analyzer to improve the signal-to-noise ratio and measurement accuracy of the signal. The Ortec 672 shape analyzer has signal processing capabilities with high signal-to-noise ratio and high precision, can effectively improve the signal quality, and reduce noise interference.

[0042] The control module includes a programmable logic controller (PLC). In one embodiment, the control module adopts a PLC of model Siemens S7-1200 to control the working state of the entire measuring device and system, coordinate the work between modules, and ensure the stable operation of the system. Siemens S7-1200 has high reliability and flexible programming capabilities, and can achieve complex system control and automated operations.

[0043] The data processing system may further include a data acquisition module, a data analysis module, and a data transmission module.

[0044] The data acquisition module is used to acquire the detection signal of the CZT detector, specifically the data after pre-amplification, shaping, and digitization by the signal processing module. In one embodiment, the data acquisition module adopts an Amptek MCA8000D data acquisition module, which has multi-channel, high-precision, and high-speed data acquisition capabilities.

[0045] The data transmission module is used to stably transmit the data from the data acquisition module to the data transmission module. In one embodiment, the data transmission module adopts a high-speed data bus; alternatively, the data transmission module can adopt an Ethernet 1000Base-T high-speed data bus to ensure the fast and stable transmission of data.

[0046] The data analysis module is used to process and analyze the data acquired by the data acquisition module and provide accurate radioactive measurement results. In one embodiment, the data analysis module is implemented by a high-performance computer, the model is but not limited to Dell PowerEdge R740, and is equipped with GammaVision spectral analysis software, which can process and analyze the acquired data in real time and provide accurate radioactive measurement results.

[0047] Reference Figure 1 and Figure 2 , when the nuclear power radioactive liquid effluent measuring device of the present invention is used, installation and debugging are first carried out.

[0048] (1) Installation process

[0049] First, determine the specific location of the pipeline to be monitored. Select a suitable detector bracket 30 according to the pipeline diameter, and evenly distribute and install 8 or more CZT detectors 10 around the pipeline 100. Ensure that each CZT detector 10 is in close contact with the surface of the pipeline 100. Install the external shielding layer 20 and the internal shielding layer 40 to ensure that the shielding material completely covers the CZT detector 10 and reduces environmental radiation interference.

[0050] Connect the signal lines of each CZT detector 10 to the Amptek MCA8000D data acquisition module, and connect to the data processing system through the Ethernet 1000Base-T high-speed data bus. Connect the high-voltage power supply module to provide a stable voltage for each CZT detector 10. Connect the signal processing module and the control module to the data processing system to ensure the overall coordinated operation of the system.

[0051] (2) System debugging

[0052] Turn on the high-voltage power supply module, gradually increase the voltage to the detector operating voltage, and check whether the output signal of each CZT detector 10 is stable. Use the GammaVision spectral analysis software to verify whether the energy resolution and sensitivity of the CZT detector 10 meet the design requirements. Conduct background radiation measurements, record the background count rates of each CZT detector 10, and adjust the position and thickness of the shielding layer (including the internal shielding layer 40 and the external shielding layer 20) to optimize the measurement accuracy. Simulate the flow of radioactive liquid effluent to detect the response time and measurement accuracy of the system to ensure that the system can monitor the radioactive dose rate in real time and accurately.

[0053] (3) Operation and maintenance

[0054] Operation:

[0055] After the installation and commissioning of the device and its system are completed, enter the normal operation mode. The data processing system receives the signals of each CZT detector 10 in real time and performs data analysis through the spectral analysis software. When the radioactive liquid effluent passes through the pipeline 100, the radioactive signals detected by the CZT detector 10 are transmitted to the data processing system, and the radioactive dose rate is calculated in real time. The control module automatically triggers an alarm signal according to the set threshold and records the data for subsequent analysis and processing.

[0056] Maintenance and calibration:

[0057] Regularly check the status of the CZT detector 10 and the shielding layers (including the internal shielding layer 40 and the external shielding layer 20) to ensure there is no looseness or damage, and replace and repair if necessary. Regularly calibrate the CZT detector 10, perform energy calibration and efficiency calibration using a standard radiation source to ensure the accuracy of the measurement results. Regularly update the spectral analysis software and the data processing system, and optimize the data processing algorithm and system performance.

[0058] (4) Emergency treatment:

[0059] When the device and its system detect an abnormally high radioactive dose rate, automatically trigger an alarm signal and send an alert message to the control center. Quickly initiate the emergency response plan, stop the discharge of radioactive liquid effluents, seal the pipeline 100 to prevent further spread. Organize professional personnel to analyze and handle the abnormal situation, identify the cause, and take corresponding protective measures to ensure environmental safety and public health.

[0060] The above are only embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be similarly included within the patent protection scope of the present invention.

Claims

1. A nuclear power radioactive liquid effluent measuring device, characterized in that: It includes a detection component installed on a pipeline, an external shielding layer wrapped around the outer periphery of the detection component, and a data processing system; The detection assembly includes a plurality of CZT detectors arranged at intervals along the circumference of the pipeline and attached to the pipeline; The data processing system is connected to the detection component, receives the detection signal sent by the detection component and performs analysis and processing, identifies the radioactive nuclides in the nuclear power radioactive liquid effluent and measures the radioactive activity of the radioactive nuclides.

2. The nuclear power radioactive liquid effluent measuring device according to claim 1, characterized in that: The detection assembly includes at least eight CZT detectors.

3. The nuclear power radioactive liquid effluent measuring device according to claim 1, characterized in that: The outer shielding layer comprises a lead shielding layer and a tungsten alloy shielding layer which are stacked inside and outside.

4. The nuclear power radioactive liquid effluent measuring device according to claim 3 is characterized in that: The thickness of the lead shielding layer is 5 cm, and the thickness of the tungsten alloy shielding layer is 3 cm.

5. The nuclear power radioactive liquid effluent measuring device according to claim 1, characterized in that: The detection assembly also includes a detector bracket, and the CZT detector is fixed in the detector bracket and positioned on the outer periphery of the pipeline through the detector bracket.

6. The nuclear power radioactive liquid effluent measuring device according to claim 5, characterized in that: The detector bracket is made of low background radiation material, including at least one of polyethylene and Teflon.

7. The nuclear power radioactive liquid effluent measuring device according to claim 1, characterized in that: The nuclear power radioactive liquid effluent measuring device also includes an internal shielding layer arranged on the inner side of the detection component.

8. The nuclear power radioactive liquid effluent measuring device according to claim 7, characterized in that: The inner shielding layer is made of polyethylene material.

9. The nuclear power radioactive liquid effluent measuring device according to any one of claims 1 to 8, characterized in that: The data processing system comprises a data acquisition module for acquiring detection signals of the CZT detector, a data analysis module for analyzing and processing the detection signals, and a data transmission module connected between the data acquisition module and the data analysis module.

10. The nuclear power radioactive liquid effluent measuring device according to any one of claims 1 to 8, characterized in that: The nuclear power radioactive liquid effluent measuring device also includes an electric control system connected between the data processing system and the detection component, and the electric control system includes a high-voltage power supply module, a signal processing module and a control module; The high-voltage power supply module provides a stable high-voltage power supply for the CZT detector; The signal processing module performs pre-amplification, shaping and digital processing on the pulse signal output by the CZT detector, and sends the processed data to the data processing system; The control module is connected to the high voltage power supply module and the signal processing module.

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