Shielding body structure of standing radioactive internal pollution measuring system and design method

Abstract

The invention relates to a shielding body structure of a standing type radioactive internal pollution measuring system and a design method, and the shielding body structure comprises a personnel shielding cabin which comprises three vertical cylindrical surfaces, a first upper top plate arranged above the vertical cylindrical surfaces, and a first lower bottom plate arranged below the vertical cylindrical surfaces, the opening angle after connection is greater than 90 degrees; the detector shielding cabin comprises three vertical cylindrical surfaces, a second upper top plate and a second lower bottom plate, the three vertical cylindrical surfaces are continuously connected, the opening angle after connection is 90 degrees, and the opening direction formed by the three vertical cylindrical surfaces faces the opening direction formed by the three vertical cylindrical surfaces; and the detector supporting module is mounted in the detector shielding cabin and is used for supporting and fixing the detector. According to the invention, the problems of compact space, poor passing ability and high detection limit value of the detector after the detected person enters the shielding body structure in the prior art are effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of ionizing radiation monitoring and protection, and in particular to a shielding structure and a design method for a standing type radioactive internal contamination measurement system. Background Art

[0002] Measurement of radioactive internal contamination is an important part of personal dose measurement for radioactive occupational personnel. The methods of internal contamination measurement mainly include direct measurement and indirect measurement. Indirect measurement refers to estimating the intake by measuring the radioactive content of samples (urine, feces, exhaled breath, etc.). Direct measurement refers to the use of an in vitro detection system to directly measure the content of radioactive substances in the human body, also known as in vivo measurement. This method is suitable for measuring radioactive nuclides that emit sufficient energy and a sufficient number of photons to escape from the body and be measured by an external detection system. Among them, direct measurement has higher accuracy than indirect measurement. Therefore, for internal exposure monitoring, direct measurement is usually preferred.

[0003] At present, the most widely used in the measurement of radioactive internal contamination in the human body is the standing type measurement system, which has the main advantages of using large-volume detectors, relatively high detection efficiency, fast measurement speed, and convenient use. In order to ensure that the detector can receive the X-rays and gamma rays emitted by the radioactive nuclides in the human body to the greatest extent, the standing type measurement system in the related art will set up a shielding structure, in which the detector and the detected person are placed, on the one hand, to shield the influence of the radioactive nuclides in the external environment, and on the other hand, to ensure that the detection field of the detector covers the measured human body to the greatest extent.

[0004] Existing shielding structures mostly use narrow rectangular shielding cabins. After the detected person enters the shielding structure, the space is compact and the passability is poor. Moreover, some shielding structures cannot completely cover the detector's field of view, resulting in a higher detection limit of the detector, affecting the sensitivity and accuracy of the measurement system.

[0005] The above problems need to be solved urgently. Summary of the invention

[0006] The invention discloses a shielding structure and a design method of a standing type radioactive internal contamination measurement system, aiming to solve the technical problems existing in the prior art.

[0007] The present invention adopts the following technical solutions:

[0008] On the one hand, the present invention provides a shielding body structure of a standing type radioactive internal contamination measurement system, comprising: a personnel shielding cabin, comprising three vertical cylinders perpendicular to the ground, a first upper top plate arranged above the vertical cylinders, and a first lower bottom plate arranged below the vertical cylinders, wherein the three vertical cylinders are continuously connected, and the opening angle after the connection is greater than ninety degrees, and the personnel shielding cabin is used to shield the background radiation in the environment; a detector shielding cabin, comprising three vertical cylinders, a second upper top plate arranged above the vertical cylinders, and a second lower bottom plate arranged below the vertical cylinders, the three vertical cylinders are continuously connected, and the opening angle after the connection is ninety degrees, wherein the opening direction formed by the three vertical cylinders is toward the opening direction formed by the three vertical cylinders, and the detector shielding cabin is used to place the detector; a detector support module, installed in the detector shielding cabin, for supporting and fixing the detector.

[0009] Optionally, it includes: outward expansion plates, including at least two plates, which are arranged at the connection point between the detector shielding cabin and the personnel shielding cabin, the two outward expansion plates are perpendicular to the ground, and the two outward expansion plates are placed at a certain angle, and the degree of outward expansion gradually increases from the end of the detector shielding cabin to the end of the personnel shielding cabin.

[0010] Optionally, the vertical cylinder, the first upper top plate and the first lower bottom plate of the personnel shielding cabin are all formed by stacking 8 to 10 layers of 10 mm thick steel plates.

[0011] Optionally, the vertical cylinder, the first upper top plate and the first lower bottom plate of the personnel shielding cabin are all formed by stacking lead plates, steel plates and copper plates in sequence from the environment to the interior of the personnel shielding cabin.

[0012] Optionally, the vertical cylinder of the personnel shielding cabin is formed by assembling a plurality of assembly plates, the plurality of assembly plates have the same height and different widths, the area of ​​the plurality of assembly plates is smaller than the area of ​​the vertical cylinder of the personnel shielding cabin, wherein the material of the plurality of assembly plates is steel plates.

[0013] Optionally, the vertical cylinder, the second upper top plate and the second lower bottom plate of the detector shielding cabin are made of 8 to 10 layers of 10 mm thick steel plates stacked together.

[0014] Optionally, the vertical cylinder, the second upper top plate and the second lower bottom plate of the detector shielding cabin are all formed by stacking lead plates, steel plates and copper plates in sequence from the environment to the inside of the detector shielding cabin.

[0015] Optionally, the opening formed by the three vertical cylinders in the detector shielding cabin is packaged with a plastic plate.

[0016] Optionally, it includes: an electronic display screen, which is arranged on the first upper top plate and is located at the connection between the first upper top plate and the second upper top plate, and the display side of the electronic display screen is facing the direction of the personnel shielding cabin.

[0017] Optionally, the detector support module includes: a support frame, which is fixedly installed in the detector shielding cabin and is provided with a cavity for placing the detector, wherein the detector is connected to a photomultiplier tube, and the photomultiplier tube is arranged outside the support frame.

[0018] According to another aspect of an embodiment of the present invention, there is also provided a design method for a shield structure of a standing type radioactive internal contamination measurement system, which is applied to the shield structure of any one of the standing type radioactive internal contamination measurement systems, and comprises: measuring the size of the detector, wherein the size comprises length, width and thickness;

[0019] Based on the size of the detector, determine the internal size of the detector shielding cabin and the size of the personnel shielding cabin;

[0020] Use multiple assembly panels to build the detector shielding cabin and the personnel shielding cabin;

[0021] Installing a support frame in the detector shielding cabin;

[0022] The detector is fixed in the support frame.

[0023] Optionally, the method also includes: using Monte Carlo simulation software to construct mathematical models of the detector, the detector shielding cabin and the personnel shielding cabin, placing gamma radiation sources of different energies at different positions outside the detector shielding cabin and the personnel shielding cabin, and using the Monte Carlo method to simulate and calculate the shielding degree of the detector shielding cabin and the personnel shielding cabin.

[0024] The technical solution adopted by the present invention can achieve the following beneficial effects:

[0025] In the embodiment of the present invention, a personnel shielding cabin includes three vertical cylinders perpendicular to the ground, a first upper top plate arranged above the vertical cylinders, and a first lower bottom plate arranged below the vertical cylinders, wherein the three vertical cylinders are continuously connected, and the opening angle after connection is greater than ninety degrees, and the personnel shielding cabin is used to shield the background radiation in the environment; a detector shielding cabin includes three vertical cylinders, a second upper top plate arranged above the vertical cylinders, and a second lower bottom plate arranged below the vertical cylinders, and the three vertical cylinders are continuously connected, and the opening angle after connection is ninety degrees, wherein the opening direction formed by the three vertical cylinders is toward the opening direction formed by the three vertical cylinders, and the detector shielding cabin is used to place the detector; and a detector support module is installed in the detector shielding cabin to support and fix the detector. The technical effect of expanding the space of the personnel shielding cabin, limiting the measurement field of the detector, reducing the impact of the background radiation of the environment, and improving the sensitivity and accuracy of the measurement system is achieved, thereby solving the problem of compact space, poor passability, and high detection limit of the detector after the detected person enters the shielding structure in the related technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

[0027] Figure 1 It is an overall structural diagram of the shielding structure of the standing type radioactive internal contamination measurement system in Example 1 of the present invention;

[0028] Figure 2 is a top view of the shielding structure of the standing type radioactive internal contamination measurement system in Example 1 of the present invention;

[0029] Figure 3 is a longitudinal cross-sectional view of the shield structure of the standing type radioactive internal contamination measurement system in Example 1 of the present invention;

[0030] Figure 4 It is a flow chart of a shield structure design method for a standing type radioactive internal contamination measurement system in embodiment 2 of the present invention.

[0031] Description of reference numerals:

[0032] 101. Personnel shielding cabin; 102. Detector shielding cabin; 103. Detector; 104. Support frame; 105. Photomultiplier tube; 106. Electronic display screen; 107. First upper top plate; 108. Second upper top plate; 109. First lower bottom plate; 110. Second lower bottom plate; 111. Shock-absorbing and buffering device. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a magnetic connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically limited.

[0035] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] First, to facilitate understanding of the embodiments of the present invention, some terms or nouns involved in the present invention are explained below:

[0037] The standing radioactive internal contamination measurement system, also known as the standing human internal exposure radiation data measurement system or the standing whole body counter, is a device that estimates the amount of radioactive nuclides in the human body through in vitro measurement. It is mainly used for internal exposure detection of employees in radioactive workplaces such as nuclear power plants, nuclear material production and processing.

[0038] The shielding structure is a component used to reduce or eliminate external radioactive interference and ensure measurement accuracy.

[0039] Expansion refers to the gradual expansion of an area or object from the inside out. This expansion is carried out at a certain angle or direction, making the originally smaller space gradually larger.

[0040] In order to solve the problems existing in the prior art, the embodiments of the present application provide a shielding structure and a design method for a standing type radioactive internal contamination measurement system.

[0041] Example 1

[0042] This embodiment provides a shielding structure of a standing type radioactive internal contamination measurement system, such as Figure 1 and Figure 2 As shown, Figure 1 is an overall structural diagram of the shielding structure of the standing type radioactive internal contamination measurement system in Example 1 of the present invention, Figure 2 It is a top view of the shielding structure of the standing type radioactive internal contamination measurement system in Example 1 of the present invention, wherein a personnel shielding cabin 101 includes three vertical cylinders perpendicular to the ground, a first upper top plate 107 arranged above the vertical cylinders, and a first lower bottom plate 109 arranged below the vertical cylinders, wherein the three vertical cylinders are continuously connected, and the opening angle after the connection is greater than ninety degrees, and the personnel shielding cabin 101 is used to shield the background radiation in the environment; a detector shielding cabin 102 includes three vertical cylinders, a second upper top plate 108 arranged above the vertical cylinders, and a second lower bottom plate 110 arranged below the vertical cylinders, wherein the three vertical cylinders are continuously connected, and the opening angle after the connection is ninety degrees, wherein the opening direction formed by the three vertical cylinders is toward the opening direction formed by the three vertical cylinders, and the detector shielding cabin 102 is used to place the detector 103; a detector support module is installed in the detector shielding cabin 102, and is used to support and fix the detector 103.

[0043] Based on the above structure, the shielding structure can shield the radioactive radiation in the external environment, thereby reducing or preventing the background radiation in the external environment from entering the measuring equipment, and ensuring the accuracy of the measurement results. For example, in the measurement of contamination in the human body, the shielding body can use materials with high atomic numbers such as lead or steel to absorb gamma rays and reduce their impact on the measuring equipment. During the measurement, the person being detected stands in front of the detector 103 and performs the measurement in accordance with the requirements of the operating guide of the detector 103. During the measurement process, the detector 103 will capture the rays released by the radioactive nuclides in the human body and convert them into electrical signals for recording and analysis. After the measurement is completed, the computer system will process and analyze the collected data. By comparing the measurement results with the energy spectrum characteristics of known radioactive nuclides, the type and content of radioactive nuclides in the human body can be determined. At the same time, the radiation dose received by the human body can also be estimated based on the measurement results.

[0044] Optionally, a personnel shielding cabin 101 with three vertical cylinders is set up, and the opening angle of the vertical cylinders after being connected is greater than ninety degrees, so that the standing space becomes larger, that is, when the detected person stands in the personnel shielding cabin 101, the space at both sides of the human body's arms becomes larger, so that the detected person can have a larger space to move during activities or rotations.

[0045] Optionally, the space of the detector shielding cabin 102 is determined by the volume of the detector 103. The detector 103 is generally a standing device. To ensure that more radioactive rays can be received, the detection limit of the detector 103 is reduced, that is, the area of ​​the detector 103 facing the detected person is as large as possible compared to the area in other directions.

[0046] Optionally, the detector support module is vertically installed inside the detector shielding cabin 102, which not only supports the detector 103 to be placed vertically, but also ensures that the detector 103 does not overturn due to vibration; in addition, the detector 103 support module is made of stainless steel, which is more stable and can well support the weight of the detector 103, and the price of stainless steel material is relatively low, which reduces the overall shielding structure cost.

[0047] In some preferred embodiments, it includes: an outward expansion plate, including at least two plates, which are arranged at the connection point between the detector shielding cabin 102 and the personnel shielding cabin 101, the two outward expansion plates are perpendicular to the ground, and the two outward expansion plates are placed at a certain angle, and the degree of outward expansion gradually increases from the end of the detector shielding cabin 102 to the end of the personnel shielding cabin 101.

[0048] Based on the above structure, in order to ensure that the detector 103 can measure a larger area, the left and right sides of the detector shielding cabin 102 adopt a "step-like" design, that is, from the inside to the outside, from the detector shielding cabin 102 to the personnel shielding cabin 101, an inclined expansion plate is placed to form an angle. In addition, the thickness of the steel plate of the detector shielding cabin 102 near the personnel shielding cabin 101 can also be gradually reduced, thereby forming an expansion angle with a smaller opening at the detector shielding cabin 102 and a larger opening at the personnel shielding cabin 101. It is effectively achieved that more radioactive rays can pass through the position of the expansion angle and reach the detector 103, and be received by the detector 103, and the detected personnel are covered to the greatest extent through the detection field of the detector, thereby achieving the technical effect of reducing the detection limit of the detector 103.

[0049] Optionally, by setting the above-mentioned outward expansion plate, the effective measurement area of ​​the detector 103 becomes all areas directly in front of the detector 103 and in the direction of the extension line of the outward expansion plate. In addition, the width of the left and right cylindrical surfaces in the detector shielding cabin 102 can be determined according to the width between the arms of the detected person and the measurement distance, thereby effectively expanding the effective measurement area of ​​the detector 103.

[0050] In some preferred embodiments, the vertical column surface of the personnel shielding cabin 101, the first upper top plate 107 and the first lower bottom plate 109 are all formed by stacking 8 to 10 layers of 10 mm thick steel plates.

[0051] Based on the above structure, the personnel shielding cabin 101 includes a first upper top plate 107, a first lower bottom plate 109 and three vertical cylinders. The above structure is formed by stacking multiple layers of steel plates. The thickness of each steel plate is 10 mm. Specifically, 8 to 10 layers of steel plates are used. The steel plates can effectively isolate the radiation in the external environment from entering the shielding structure. If the number of layers of steel plates is small, the shielding effect may be low, affecting the subsequent detection results. If the number of layers of steel plates is large, the cost will increase. Steel plates are metal materials with high costs. When there are more than 10 steel plates, the cost of the shielding structure will increase. Therefore, the number of steel plate layers is set to 8 to 10 layers, which effectively achieves the goal of ensuring the shielding effect while reducing the use cost.

[0052] In some preferred embodiments, the vertical cylinder, the first upper top plate 107 and the first lower bottom plate 109 of the personnel shielding cabin 101 are all formed by stacking lead plates, steel plates and copper plates in sequence from the environment to the interior of the personnel shielding cabin 101.

[0053] Based on the above structure, in the external environment, there is not only background radiation, but also cosmic rays or secondary rays, which may affect the detection results, so lead plates and copper plates can be added to the surface of the steel plate to shield cosmic rays, environmental background rays, and secondary rays generated by the steel plate and lead plate. Specifically, the lead plate is set on the outer surface of the steel plate close to the radiation environment, and the copper plate is set on the inner surface of the steel plate close to the shielding structure. Since the lead plate has the strongest ability to shield radiation and has a certain ability to absorb radiation, it is set on the outermost side. The copper plate is mostly used to absorb the bremsstrahlung generated by the gamma rays and beta rays of radioactive lead isotopes, and can be set on the inner side of the steel plate, which effectively improves the shielding effect.

[0054] In some preferred embodiments, the vertical cylinder of the personnel shielding cabin 101 is assembled by multiple assembly plates, the multiple assembly plates have the same height and different widths, the area of ​​the multiple assembly plates is smaller than the area of ​​the vertical cylinder of the personnel shielding cabin 101, and the material of the multiple assembly plates is steel plate.

[0055] Based on the above structure, some usage scenarios involve adjustment of the position of the measurement system. In order to improve the convenience of disassembly and assembly of the shielding structure and make it more convenient to carry, the large-area shielding cabin, the personnel shielding cabin 101 and the detector shielding cabin 102 can be split into multiple assembly plates of the same height. It should be noted that the shielding cabin includes lead plates, steel plates and copper plates.

[0056] Optionally, when splitting the shielding cabin into multiple assembly plates, the height needs to be the same and the width is not restricted. Multiple assembly plates with different widths can be made. During the assembly process, the appropriate assembly plate is selected according to the actual situation, so that the width of the shielding cabin can be increased or decreased, that is, the internal space of the shielding body structure is changed, and the controllability of the space is effectively realized. The increased space can improve the passability.

[0057] In some preferred embodiments, the vertical cylinder of the detector shielding cabin 102, the second upper top plate 108 and the second lower bottom plate 110 are formed by stacking 8 to 10 layers of 10 mm thick steel plates.

[0058] Based on the above structure, the thickness of the vertical cylinder, the second upper top plate 108 and the second lower bottom plate 110 of the detector shielding cabin 102 should be determined according to the type and energy of radiation to be shielded. Generally speaking, the thicker the shielding body is, the better its shielding effect is, but it will also increase the cost and weight. Using 8 to 10 layers of steel plates, the steel plates can effectively isolate the radiation in the radiation environment from entering the shielding structure. If the number of steel plates is small, the shielding effect may be low, affecting the subsequent detection results. If the number of steel plates is large, it will lead to increased costs. Steel plates are metal materials and have a high cost. When there are more than 10 steel plates, the cost of the shielding structure will increase. Therefore, the number of steel plate layers is set to 8 to 10 layers, which effectively achieves the goal of ensuring the shielding effect while reducing the cost of use.

[0059] Optionally, the geometric shape of the detector shielding cabin 102 should be able to effectively block radiation. For example, for point source radiation, a spherical or cylindrical shielding body can be used; for surface source radiation, a flat or box-shaped shielding body can be used. Since the detector 103 is generally a rectangular parallelepiped structure, the detector shielding cabin 102 is set to a rectangular parallelepiped structure. When it is necessary to shield multiple radiations at the same time, a combination of shielding bodies of multiple materials can be used. For example, in a mixed radiation field of gamma rays and neutrons, a mixed sandwich shielding body of two materials that are anti-gamma rays and anti-neutrons can be used. When shielding general radiation environments, more common steel plates can be used.

[0060] In some preferred embodiments, the vertical cylinder of the detector shielding cabin 102, the second upper top plate 108 and the second lower bottom plate 110 are all formed by stacking lead plates, steel plates and copper plates in sequence from the environment to the inside of the detector shielding cabin 102.

[0061] Based on the above structure, in the external environment, there is not only background radiation, but also cosmic rays or secondary rays, which may affect the detection results, so lead plates and copper plates can be added to the surface of the steel plate to shield cosmic rays, environmental background rays, and secondary rays generated by the steel plate and lead plate. Specifically, the lead plate is set on the outer surface of the steel plate close to the radiation environment, and the copper plate is set on the inner surface of the steel plate close to the shielding structure. Since the lead plate has the strongest ability to shield radiation and has a certain ability to absorb radiation, it is set on the outermost side. The copper plate is mostly used to absorb the bremsstrahlung generated by the gamma rays and beta rays of radioactive lead isotopes, and can be set on the inner side of the steel plate, which effectively improves the shielding effect.

[0062] In some preferred embodiments, the openings formed by the three vertical cylinders in the detector shielding cabin 102 are sealed with plastic plates.

[0063] Based on the above structure, the detector 103 receives radioactive rays from the human body, and a plastic plate is used to encapsulate the opening where the detector shielding cabin 102 is connected to the personnel shielding cabin 101. The plastic plate is encapsulated with materials such as polyethylene or nylon. This material has a low cost and a weak ability to block rays, which effectively prevents the detector from being damaged by collision and does not affect the measurement of the human body.

[0064] In some preferred embodiments, it includes: an electronic display screen 106, which is arranged on the first upper top plate 107 and located at the connection between the first upper top plate 107 and the second upper top plate 108, and the display side of the electronic display screen 106 faces the direction of the personnel shielding cabin 101.

[0065] Based on the above structure, Figure 3 As shown, Figure 3 It is a longitudinal cross-sectional view of the shielding structure of the standing type radioactive internal contamination measurement system in Example 1 of the present invention. The detector 103 takes a long time during the measurement process. In order to reduce the position change of the detected person during the measurement process and improve the concentration of the person, an electronic display screen 106 is set at the connection between the first upper top plate 107 and the second upper top plate 108. The electronic display screen 106 can display personnel information, the detection progress and detection results of the detector 103, so that the detected person can watch and confirm at any time.

[0066] In some preferred embodiments, the support frame 104 is fixedly installed in the detector shielding cabin 102, and is provided with a cavity for placing the detector 103, wherein the detector 103 is connected to the photomultiplier tube 105, and the photomultiplier tube 105 is arranged on the outside of the support frame 104; a fastening device is installed between the support frame 104 and the detector shielding cabin 102, and is used to fix the support frame 104 to prevent tipping; the shock-absorbing and buffering device 111 is made of flame-retardant material and is wrapped around the side of the detector 103 to reduce the damage of the detector 103 caused by vibration.

[0067] Based on the above structure, two support frames 104 are provided, each support frame 104 includes two frames, the two frames can be opened, the detector 103 is placed in the opened cavity, and then the two frames are closed. A fastening device is provided to fasten the support frame 104 and the detector shielding cabin 102, so that the support frame 104 can effectively fix and support the detector 103, prevent the detector 103 from falling over, and when moving, the detector 103 can be taken out for easy transportation.

[0068] Optionally, multiple detectors 103 can be provided, and the multiple detectors 103 are arranged to have approximately the same width and height as the detected person. Generally, two detectors 103 are provided, arranged in an upper and lower manner, so two support frames 104 are also provided, supporting the two detectors 103 respectively. The detector 103 requires a photomultiplier tube 105 for signal amplification during the detection process, so the photomultiplier tube 105 is connected to the detector 103, and after the photomultiplier tube 105 is fastened to the detector 103, it is fixed in the detector shielding cabin 102 by the support frame 104.

[0069] Through the above-mentioned shielding structure of the standing radioactive internal contamination measurement system, the technical effects of expanding the space of the personnel shielding cabin, limiting the measurement field of view of the detector, reducing the impact of the environmental radiation background, and improving the sensitivity and accuracy of the measurement system are achieved, thereby solving the problems in related technologies such as compact space and poor passability after the detected personnel enter the shielding structure, and a high detection limit of the detector.

[0070] Example 2

[0071] According to an embodiment of the present invention, there is also provided an embodiment of a method for designing a shield structure of a standing type radioactive internal contamination measurement system. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0072] Figure 4 is a flow chart of a method for designing a shield structure of a standing type radioactive internal contamination measurement system in Embodiment 2 of the present invention, such as Figure 4 As shown, the method comprises the following steps:

[0073] According to another aspect of an embodiment of the present invention, a design method for a shield structure of a standing type radioactive internal contamination measurement system is provided, which is applied to any shield structure of a standing type radioactive internal contamination measurement system, and includes:

[0074] Step S1, measuring the size of the detector 103, wherein the size includes length, width and thickness;

[0075] Step S2, based on the size of the detector 103, determine the internal size of the detector shielding cabin 102, and use multiple assembly boards to build the detector shielding cabin 102;

[0076] Step S3, based on the size of the detector shielding cabin 102, determine the size of the personnel shielding cabin 101, and use multiple assembly panels to build the personnel shielding cabin 101;

[0077] Step S4, installing a support frame 104 in the detector shielding cabin, and placing the detector 103 in the support frame 104;

[0078] Step S5, using the Monte Carlo method to simulate and calculate the shielding effects of the detector shielding cabin 102 and the personnel shielding cabin 101.

[0079] Optionally, the width and depth of the inner cavity of the detector shielding cabin 102 are determined according to the outer dimensions of the detector 103; the left and right sides, top surface, bottom surface and the side away from the personnel shielding cabin 101 of the detector shielding cabin 102 are all made of 8 to 10 layers of 10 mm thick steel plates; the side of the detector shielding cabin 102 facing the detected person is encapsulated with plastic plates such as polyethylene or nylon. In order to ensure that the detector 103 can measure a larger range of areas, the left and right sides of the detector 103 end shielding module adopt a "step-shaped" design, that is, from the inside to the outside, the width of the steel plate gradually increases to form an angle.

[0080] Optionally, the left and right sides, top surface, bottom surface and the side away from the detector shielding cabin 102 of the personnel shielding cabin 101 are all made of 8 to 10 layers of 10 mm thick steel plates stacked together; the distance between the side of the personnel shielding cabin 101 away from the detector shielding cabin 102 and the plastic plate at the end of the detector 103 is determined by the body width of the detected person and the measurement distance; in order to ensure that the detector 103 is not directly exposed to rays outside the shielding body structure, it is necessary to ensure that the maximum measurement area of ​​the detector 103 is within the range specified by the personnel end shielding module.

[0081] Optionally, a multi-layer shielding design can be made of lead plates, steel plates, and copper plates to shield cosmic rays, environmental background rays, and secondary rays generated by the interaction of steel plates and lead plates; large-area steel plates and lead plates can be decomposed into small-sized assembly plates of the same height and different widths to improve the convenience of disassembly and assembly of the shielding structure;

[0082] Optionally, the detector support module is vertically installed in the cavity of the detector shielding cabin 102, which not only supports the detector 103 to be placed vertically, but also ensures that the detector 103 does not overturn due to vibration; the detector support module is made of stainless steel.

[0083] Optionally, a Monte Carlo simulation software is used to construct a mathematical model of the detector 103, the detector shielding cabin 102 and the personnel shielding cabin 101, and gamma radiation sources of different energies are placed at different positions outside the detector shielding cabin 102 and the personnel shielding cabin 101, and the Monte Carlo method is used to simulate and calculate the shielding degree of the detector shielding cabin 102 and the personnel shielding cabin 101.

[0084] Optionally, in order to ensure the shielding effect of the shielding structure, in addition to actual measurement after construction, simulation measurement of the system software can also be performed. First, determine the size and material of the shielding structure; second, determine the size of the detector 103 and the crystal and packaging structure materials; then, use Monte Carlo simulation software to build a mathematical model of the detector 103 and the shielding body; finally, place gamma radiation sources of different energies at different distances outside the shielding structure, and use the Monte Carlo method to simulate and calculate the shielding effect of the shielding body.

[0085] Through the above steps S1 to S5, the technical effects of expanding the space of the personnel shielding cabin, limiting the measurement field of view of the detector, reducing the impact of the environmental radiation background, and improving the sensitivity and accuracy of the measurement system are achieved, thereby solving the problems in the related technology that the space is compact and the passability is poor after the detected person enters the shielding structure, and the detection limit of the detector is high.

[0086] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A shielding structure of a standing type radioactive internal contamination measurement system, characterized in that: include: A personnel shielding cabin (101) comprises three vertical cylinders perpendicular to the ground, a first upper top plate (107) arranged above the vertical cylinders, and a first lower bottom plate (109) arranged below the vertical cylinders, wherein the three vertical cylinders are continuously connected, and the opening angle after the connection is greater than ninety degrees, and the personnel shielding cabin (101) is used to shield background radiation in the environment; A detector shielding cabin (102) comprises three vertical cylinders, a second upper top plate (108) arranged above the vertical cylinders, and a second lower bottom plate (110) arranged below the vertical cylinders, wherein the three vertical cylinders are continuously connected, and the opening angle after connection is ninety degrees, wherein the opening direction formed by the three vertical cylinders faces the opening direction formed by the three vertical cylinders, and the detector shielding cabin (102) is used to place a detector (103); A detector supporting module is installed in the detector shielding cabin (102) and is used to support and fix the detector (103).

2. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: include: The outward expansion plates include at least two plates, which are arranged at the connection point between the detector shielding cabin (102) and the personnel shielding cabin (101). The two outward expansion plates are perpendicular to the ground and are placed at a certain angle. The degree of outward expansion gradually increases from the end of the detector shielding cabin (102) to the end of the personnel shielding cabin (101).

3. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: The vertical column surface, the first upper top plate (107) and the first lower bottom plate (109) of the personnel shielding cabin (101) are all formed by stacking 8 to 10 layers of 10 mm thick steel plates.

4. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: The vertical column, the first upper top plate (107) and the first lower bottom plate (109) of the personnel shielding cabin (101) are all formed by stacking lead plates, steel plates and copper plates in sequence from the environment to the interior of the personnel shielding cabin (101).

5. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: The vertical cylindrical surface of the personnel shielding cabin (101) is formed by assembling a plurality of assembly plates, wherein the plurality of assembly plates have the same height and different widths, and the area of ​​the plurality of assembly plates is smaller than the area of ​​the vertical cylindrical surface of the personnel shielding cabin (101), wherein the material of the plurality of assembly plates is steel plate.

6. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: The vertical column surface, the second upper top plate (108) and the second lower bottom plate (110) of the detector shielding cabin (102) are formed by stacking 8 to 10 layers of 10 mm thick steel plates.

7. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: The vertical cylinder, the second upper top plate (108) and the second lower bottom plate (110) of the detector shielding cabin (102) are all formed by stacking lead plates, steel plates and copper plates in sequence from the environment to the inside of the detector shielding cabin (102).

8. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: The openings formed by the three vertical cylinders in the detector shielding cabin (102) are sealed with a plastic plate.

9. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1 is characterized in that: include: An electronic display screen (106) is arranged on the first upper top plate (107) and is located at the connection between the first upper top plate (107) and the second upper top plate (108), and the display side of the electronic display screen (106) is oriented in the direction of the personnel shielding cabin (101).

10. The shield structure of the standing type radioactive internal contamination measurement system according to claim 1, characterized in that: The detector support module comprises: A support frame (104) is fixedly mounted in the detector shielding cabin (102) and is provided with a cavity for placing the detector (103), wherein the detector (103) is connected to a photomultiplier tube (105), and the photomultiplier tube (105) is arranged outside the support frame (104); A fastening device, installed between the support frame (104) and the detector shielding cabin (102), used to fix the support frame (104) to prevent it from tipping over; The shock absorbing and buffering device (111) is made of flame retardant material and is wrapped around the side of the detector (103) to reduce damage to the detector (103) caused by vibration.

11. A design method for a shield structure of a standing radioactive internal contamination measurement system, characterized in that: The shielding structure of the standing type radioactive internal contamination measurement system according to any one of claims 1 to 10 comprises: Measuring dimensions of the detector (103), wherein the dimensions include length, width, and thickness; Based on the size of the detector (103), determine the internal size of the detector shielding cabin (102) and the size of the personnel shielding cabin (101); A detector shielding cabin (102) and a personnel shielding cabin (101) are constructed using a plurality of assembly plates; Installing a support frame (104) in the detector shielding cabin (102); The detector (103) is fixed in the support frame (104).

12. The design method of the shield structure of the standing type radioactive internal contamination measurement system according to claim 11 is characterized in that: The method further comprises: A mathematical model of the detector (103), the detector shielding cabin (102) and the personnel shielding cabin (101) is constructed using Monte Carlo simulation software, gamma radiation sources of different energies are placed at different positions outside the detector shielding cabin (102) and the personnel shielding cabin (101), and the shielding degree of the detector shielding cabin (102) and the personnel shielding cabin (101) is simulated and calculated using the Monte Carlo method.

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