A device for handling radioactive material

Abstract

The application provides a device for processing radioactive material, comprising a material container, a material channel and a shielding structure, the shielding structure comprising a first level shielding and a second level shielding, the second level shielding being located outside the first level shielding, the first level shielding comprising a container shielding and a channel shielding, the container shielding being arranged outside the material container, the channel shielding at least partially surrounding the material channel in the device, the material channel being entirely surrounded by the shielding structure, and the second level shielding comprising a shielding window. The device is provided with the shielding window, which is more convenient for engineers to operate, inspect and maintain during the operation of the device, reduces the difficulty of maintaining the nuclear facility, and reduces the thickness and weight of the device by adjusting the parameters of the container shielding and the channel shielding, selecting the optimal shielding material and structural combination to protect and shield ionizing radiation, and reducing the construction and operation and maintenance costs.

Description

Technical Field

[0001] The present invention relates to the technical field of radioactive material shielding, and in particular to a device for processing radioactive materials. Background Art

[0002] Due to various needs, nuclear facilities such as nuclear power plants, reprocessing plants, nuclear chemical facilities, and nuclear fuel manufacturing plants will extract materials (liquid, solid, or gas) from radioactive systems such as power systems, process systems, production systems, or waste systems through pumps into chambers or sampling cabinets with radiation shielding functions for detection and analysis during operation to determine the system operating status or material and product indicators.

[0003] In order to protect and shield the ionizing radiation of radioactive samples extracted into the device, the device must adopt a shielding scheme that meets the radiation protection indicators, so that the radiation level in the external environment of the device is kept within an acceptable range, and the radiation exposure dose and risk of personnel are controlled and reduced.

[0004] The parameters of radioactive samples in the radioactive system of nuclear facilities, such as physical state, nuclide composition, pH, temperature, etc., are quite complex and variable. The radioactive samples in the radioactive system that need to be sampled for detection and analysis have complex radionuclide compositions, usually containing a large number of radioactive substances, such as uranium, plutonium, neptunium, americium, curium and other long-lived actinides, as well as a large number of radioactive fission products, such as 90 Sr. 90 Y. 137 Cs, etc.; radioactive samples produce many types of radiation, such as α particles, β rays, γ rays and neutrons. They will also produce bremsstrahlung photons (X-rays), neutrons from the (α, n) reaction between α particles and light nuclei, and secondary photons produced by the interaction between neutrons and matter.

[0005] For example, the more depleted the spent fuel assemblies received by a reprocessing plant, the higher the radioactivity level in the source term. Photon radiation dominates, and the intensity and proportion of neutron radiation in the total radiation exposure also increase. The fission products in the source term, primarily photon and beta emitters, have much shorter half-lives than long-lived actinides, such as the primary alpha and neutron emitters. Therefore, the total radioactivity of the source term decreases with cooling, while the proportion of neutrons in the total radiation exposure increases. Using conventional shielding solutions for these devices requiring shielding protection typically results in thick and heavy shielding, high processing and manufacturing complexity, high cost, strict quality requirements for supporting nuclear equipment, and inconvenient operation and operation, resulting in poor safety, economic efficiency, and low operability indicators.

[0006] Adopting a hot cell solution for a reprocessing plant would significantly increase construction costs, potentially making them unacceptable. The total cost of a single high-level sampling and analysis hot cell and its supporting facilities and equipment could reach tens of millions of yuan. Furthermore, the hot cell occupies a large area, impacting facility and system layout, and disrupting personnel and logistics flows. Furthermore, the difficulty of operating the robotic arm would further reduce work efficiency.

[0007] A conventional solution is used for the reprocessing plant. Due to the extremely high radioactivity level of the sampled high-level waste liquid, the thickness of the conventional sampling cabinet is extremely large. After demonstration, it was found that the only feasible solution in the engineering project is to use one-piece cast iron casting, resulting in the front cabinet body being tens of centimeters thick and weighing nearly one hundred tons, which brings a huge load burden to the structure of the facility plant and poses a huge potential safety risk. Personnel cannot operate and observe, and the processing and manufacturing are difficult, resulting in a significant increase in the cost.

[0008] Existing patent CN216449743U discloses a radiation shielding layered isolation sampling device for nuclear power plants. By effectively arranging the radioactive part and the non-radioactive part of the nuclear sampling device in layers and shielding only the separated radioactive part, the material used in the shielding layer can be effectively reduced, thereby reducing the weight and volume of the device.

[0009] The existing patent CN207883335U discloses a sampling bottle delivery device for a high-radioactive sampling cabinet. The device sets a sampling cabinet baffle to isolate the high-radiation area and the personnel operation area, and sets a sampling bottle delivery pipe through the sampling cabinet baffle to ensure that the sampling bottles are safely and smoothly delivered into the sampling cabinet box.

[0010] The above scheme does not implement targeted shielding for the different types of radiation generated by the samples, and the radiation protection and shielding effects are poor. At the same time, it cannot provide high radiation safety protection for engineering personnel performing operations, maintenance, inspection, etc. Summary of the Invention

[0011] In response to the defects in the existing technology, the first purpose of the present invention is to set up multi-level shielding to reduce the external radiation intensity of radioactive samples layer by layer, reduce the possibility of potential radiation risks, and improve the safety of the device.

[0012] The second purpose of the present invention is to provide targeted protection and shielding against various ionizing radiations while reducing the thickness and weight of the device, lowering construction and operation and maintenance costs, and saving space.

[0013] A third object of the present invention is to provide a shielding window, while meeting engineering requirements, to facilitate operation, inspection, and maintenance by engineering personnel during operation of the device, thereby reducing the difficulty of nuclear facility maintenance. To achieve the above object, the present invention provides a device for handling radioactive materials, comprising a material container, a material channel, and a shielding structure. The shielding structure comprises a first-level shield and a second-level shield, the second-level shield being located external to the first-level shield. The first-level shield comprises a container shield and a channel shield. The container shield is provided externally to the material container, and the channel shield at least partially surrounds the material channel within the device. The outer periphery of the material channel is completely surrounded by the shielding structure. The second-level shield comprises a shielding window.

[0014] Furthermore, the shielding materials of the first-level shielding and the second-level shielding are different.

[0015] Furthermore, the upper end of the material container is not higher than the upper surface of the container shield, and the distance between the outer side surface of the material container and the outer side surface of the container shield in any direction is 5 cm-20 cm.

[0016] Furthermore, an operating arm is provided on the container shield, and the operating arm can be rotated to different material container positions for operating the material or material container.

[0017] Furthermore, the channel shielding is an integrally formed body of the same material or a spliced ​​structure of the same material, or is a channel shielding layer of 3-6 layers made of different materials, the innermost and outermost channel shielding layers are metal plates, and the thickness of the channel shielding is 5cm-20cm.

[0018] Furthermore, the materials of the container shielding and the channel shielding include neutron shielding materials.

[0019] Furthermore, the material between the innermost layer and the outermost layer of the channel shield and the material of the container shield are selected from lead boron polyethylene, tungsten boron polyethylene, boron steel, alloy material X m H n -BW-Al or alloy material X m H n -B4C-W-Al, one or more of which X m H n The channel shield is made of hydrogenated metal, and the innermost and outermost channel shielding layers are made of carbon steel or stainless steel.

[0020] Furthermore, metal partitions are provided between the shielding channel layers, and the thickness of the metal partitions is 1 mm to 50 mm.

[0021] Furthermore, the second-level shielding includes 2-6 second-level shielding layers, the second-level shielding thickness is 3mm-600mm, and the second-level shielding at least covers other surfaces of the device except the bottom surface.

[0022] Furthermore, the second-level shielding includes multiple surfaces, the multiple surfaces are integrally formed, or each of the multiple surfaces is integrally formed.

[0023] Furthermore, the side wall of the second-level shielding is penetrated by an operating robot, and there are two operating robots. The operating robots are located above or below the shielding window, or the operating robots are located on both sides of the shielding window.

[0024] Furthermore, the length of the operating robot matches the size and position of the material container and the container shield, completely covering the area where the material container is located.

[0025] Furthermore, the inner layer of the second-level shield is provided with a sealing air hood, the height of the sealing air hood is not lower than the elevation of the material container and the upper surface of the container shield, and the thickness is 0.3mm-20mm.

[0026] Furthermore, the shielding window includes 2 to 6 shielding window layers made of different materials, and the outermost shielding window layer is protective glass.

[0027] Furthermore, the innermost layer of the shielding window layer of the shielding window is radiation-resistant glass, and at least one layer of the shielding window layer of the shielding window is radiation-proof glass.

[0028] Furthermore, the shielding window includes a shielding window frame, which is arranged in a stepped shape from the inside to the outside and is made of metal.

[0029] Furthermore, the device for handling radioactive materials is a radioactive sampling cabinet.

[0030] The application of the technical solution of the present invention should have at least the following beneficial effects:

[0031] 1. The present invention provides shielding bodies on the inner and outer layers of the device to reduce the external radiation intensity of the radioactive sample layer by layer. Even if the device is partially damaged, the external dose rate of the device can still be controlled within an acceptable range for radiation protection, thereby achieving higher safety.

[0032] 2. The present invention shields various types of ionizing radiation rays or particles, especially strong neutron radiation, mixed radiation and strong secondary radiation, by adjusting the parameters of container shielding, channel shielding, sampling cabinet shielding body and shielding window, such as material, size, shape, structure or combination form, so that the maximum dose rate outside the device does not exceed 10mSv / h, and has good comprehensive radiation protection and shielding performance.

[0033] 3. By adjusting the parameters of container shielding and channel shielding and selecting the optimal shielding material and structural combination, the present invention can significantly reduce the thickness and weight of the device while achieving the same radiation protection control indicators, while reducing the difficulty of lifting and installation, and improving the efficiency of transportation, lifting, installation and construction.

[0034] 4. The present invention installs shielding windows on the device for handling radioactive materials to provide effective radiation safety protection for workers and facilitates engineering personnel to operate, inspect and repair the device during operation, thereby reducing the difficulty of nuclear facility maintenance.

[0035] 5. The present invention provides an operating manipulator and an operating arm on the device for handling radioactive materials to assist workers in completing operations such as sampling, pouring materials, and moving samples, thereby effectively reducing the radiation intensity received by workers and further strengthening radiation safety.

[0036] 6. The present invention does not require additional compensating shielding materials and structures and corresponding supporting facilities or devices, can reduce the overall size and materials of nuclear facility shielding, increase space utilization, facilitate the layout and installation of systems and equipment in the space, eliminate unnecessary pipes and brackets, etc., and improve the overall economy of nuclear facility shielding. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0038] Figure 1 This is a schematic diagram of the device for processing radioactive materials in the present application when the channel shielding is a radial single structure;

[0039] Figure 2 is a schematic cross-sectional view of the apparatus for treating radioactive materials of the present application;

[0040] Figure 3 This is a schematic diagram of the device for processing radioactive materials in the present application when the channel shielding is a multi-layer composite structure of multiple materials.

[0041] The above drawings include the following reference numerals:

[0042] 1. Material container; 2. Material channel; 3. Shielding structure;

[0043] 31. First level shielding; 311. Container shielding; 312. Channel shielding;

[0044] 3121. Channel shielding single-layer shielding body; 3122. Channel shielding innermost shielding body; 3123. Channel shielding middle-layer shielding body; 3124. Channel shielding outermost shielding body.

[0045] 32. Second-level shielding; 321. Shielding window; 3211. First layer of glass for shielding window; 3212. Second layer of glass for shielding window; 3213. Third layer of glass for shielding window; 3214. Fourth layer of glass for shielding window; 3215. Shielding window frame;

[0046] 322, sampling cabinet shield; 3221, sampling cabinet shield innermost shield; 3222, sampling cabinet shield middle shield; 3223, sampling cabinet shield outermost shield;

[0047] 4. Operating manipulator; 5. Sealing air hood; 6. Operating arm. DETAILED DESCRIPTION

[0048] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0049] The present invention is further described in detail below with reference to specific examples. These examples should not be construed as limiting the scope of protection claimed in the present invention.

[0050] Example

[0051] Based on the above technical background, a new device is proposed. The device can shield various types of radiation and mixed radiation, the thickness of the device meets the operational range, the weight of the sampling cabinet can be borne by the facility and the plant, and it meets the radiation protection indicators. The cost is controlled below the acceptable level for the project.

[0052] In order to achieve the above object, the present invention provides a device for processing radioactive materials.

[0053] Figure 1 FIG. 1 shows a schematic diagram of a device for processing radioactive materials according to an embodiment of the present application ( Figure 1 (The operating manipulator, sealing air cover, and operating arm are not shown in the figure). The device is a radioactive sampling cabinet, which includes a material container 1, a material channel 2 and a shielding structure 3. The shielding structure 3 includes a first-level shield 31 and a second-level shield 32. The second-level shield 32 is located outside the first-level shield 31. The first-level shield 31 includes a container shield 311 and a channel shield 312. The container shield 311 is set outside the material container 1, and the channel shield 312 at least partially surrounds the material channel 2 in the device. The outer periphery of the material channel 2 is completely surrounded by the shielding structure 3. The second-level shield 32 includes a shielding window 321 and a sampling cabinet shield body 322.

[0054] The material container 1 is groove-shaped, and its main body is located in the container shield 311 . The upper end of the material container 1 is not higher than the upper surface of the container shield 311 , so as to shield the radiation generated by the radioactive sample in the material container 1 to a greater extent.

[0055] like Figure 2As shown, in another embodiment of the present application, an operating arm 6 is provided on the container shield 311, and the operating arm 6 can be rotated to different positions of the material container 1 to realize tasks such as automatic pouring, sampling, opening or closing the material container, and transferring the sampling piece.

[0056] Generally speaking, in engineering, the optimal distance between the side surface of the material container 1 and the side surface of the container shield 311 in any direction is 1 cm-500 cm, and the number of material containers 1 that can be placed is 1-20.

[0057] To achieve a better shielding effect, in this embodiment, the distance between the outer side of the material container 1 and the outer side of the container shield 311 in any direction is set to 5cm-20cm, and the radial size of the container shield 311 matches the size and number of the material containers 1, limiting the number of material containers 1 placed on the container shield 311 to 1-12. Figure 1 As shown, the material channel 2 is connected to the material container 1 , and the channel shield 312 encloses the material channel 2 therein. This design can reduce the radiation of the radioactive sample in the material channel 2 and the radiation leakage beam at the bottom of the material container 1 .

[0058] Specifically, the radial dimensions of the channel shield 312 need to match those of the container shield 311, and its maximum dimension does not exceed the side surface of the container shield 311. Generally, the total thickness of the channel shield 312 is 1 cm to 500 cm. To achieve better shielding effect, the total thickness of the channel shield 312 in this embodiment is set to 5 cm to 20 cm.

[0059] The channel shield 312 is an integrally formed body made of the same material or a spliced ​​structure made of the same material, or is a channel shield layer composed of 3 to 6 layers made of different materials.

[0060] Specifically, such as Figure 1 In the channel shield 312 shown, a channel shield single-layer shielding body 3121 is used for radiation shielding. Figure 2 Three layers of channel shielding layers are used, including the innermost channel shielding shielding body 3122, the middle channel shielding shielding body 3123, and the outermost channel shielding shielding body 3124. The innermost and outermost channel shielding layers are metal plates, and metal partitions are set between the shielding channel layers. The thickness of the metal partitions is 1mm-50mm.

[0061] Specifically, the container shield 311 and the channel shield 312 of the first-level shield 31 can be manufactured by pouring or casting, forging, 3D printing, turning and milling, cutting, etc. using one or more materials once or multiple times; or by splicing multiple pieces of one or more materials, and the specific forms include but are not limited to one or more of direct splicing, bonding, welding, mortise and tenon connection, bolt connection or pin connection.

[0062] The cross-sections of the container shield 311 and the channel shield 312 may be circular, elliptical, rectangular, regular polygonal, or regular polygonal, and the optimal cross-sections are circular, square, regular hexagonal, or regular octagonal.

[0063] In order to avoid radiation directly penetrating the gaps, the container shield 311 can be spliced ​​in an staggered manner to avoid direct penetration of gaps from the material container 1 to the outside of the container shield 311; the channel shield 312 can be staggered or use integral materials for the innermost and outermost layers, and the middle layer can be cast, filled, and poured with solidifiable materials, liquids, granular, fibrous, and block-shaped shielding materials to avoid direct penetration of gaps from the upper and lower material pipes of the material channel 2 to the outside of the channel shield 312.

[0064] Specifically, the container shield 311 and the channel shield 312 are made of neutron shielding materials. Because different radioactive samples generate different types and intensities of radiation, the container shield 311 and the channel shield 312 of the first-stage shield 31 can also be made of metals, composite shielding materials, or multi-component alloy materials to provide corresponding particle radiation shielding, thereby achieving excellent shielding effects.

[0065] Among them, metal elements can effectively shield the gamma rays directly emitted by fission and the secondary gamma rays produced by neutrons and shielding materials.

[0066] In addition, for radioactive samples whose neutron radiation dose accounts for more than 10% of the total dose, such as actinide products and liquids in post-processing facilities and high-level waste liquids, the selected shielding materials must play a certain role in neutron moderation and reducing secondary radiation. Polyethylene, boron-containing polyethylene, lead-boron polyethylene, polypropylene, epoxy resin, boron-containing epoxy resin, multi-component alloy material X m H n -BW-Al or X m H n -B4C-W-Al, where X m H n For hydrogenated metals, the above materials are rich in light nuclear elements, such as hydrogen. The mechanism characteristics of the high probability of light nuclear elements interacting with neutrons in these materials are used to shield neutrons. At the same time, the gamma energy generated by the radiation capture of boron and neutrons in the materials is low, which can further reduce secondary radiation.

[0067] Specifically, for radioactive samples that emit single electrons (including β- and β+) or charged particles, or contribute more than 0.1% of mixed radiation, such as materials used in nuclear power and post-processing operations or processes containing β-emitting nuclides with an activity concentration exceeding 1 MBq / L (or 0.01 MBq / g), materials with the ability to reduce secondary radiation (including bremsstrahlung) can be selected. When β rays are blocked by the radioactive source material itself and other materials surrounding the source (shielding), they interact with the shielding to generate bremsstrahlung photons (X-rays). The bremsstrahlung photon fraction is directly proportional to the shielding material's atomic number, Z. Therefore, the lower atomic number of these materials can be used to reduce the bremsstrahlung yield, while the other components in the material shield the generated bremsstrahlung photons.

[0068] In addition, for mixed radiation of any combination of neutrons, photons and electrons, where the contribution of each type of radiation to the dose is between 10% and 90%, such as post-processing radioactive products and liquids and high-level waste liquids, materials with good comprehensive shielding properties can be selected, such as lead / tungsten boron polyethylene, lead / tungsten boron resin, boron-containing steel, multi-component alloy materials (X m H n -BW-Al or X m H n -B4C-W-Al, where X m H n is a metal hydride), and the mechanism of action is similar to the above-mentioned neutron and β shielding.

[0069] In order to slow down fast neutrons, components with high inelastic scattering cross sections, such as tungsten, can also be used. The slowed down medium and low energy neutrons undergo elastic scattering with light nuclear elements, further reducing their energy and slowing them down into thermal neutrons. Then, nuclides with large absorption cross sections, such as boron, are used to absorb the thermal neutrons slowed down by them.

[0070] In engineering, the optimal shielding materials for container shield 311 are cast iron, cast steel, carbon steel, stainless steel, lead, lead-antimony alloy, polyethylene, boron-containing polyethylene, lead-boron polyethylene, and multi-component alloys. The optimal solution for channel shield 312 is to use carbon steel, stainless steel, aluminum alloy, or magnesium alloy as the inner and outer layers, with a middle layer made of a variety of shielding materials. This can be achieved by mixing and pouring multiple materials, or by placing metal partitions such as carbon steel or stainless steel between the different shielding materials, with a thickness of 1mm-50mm. The middle layer can be made of concrete, filled with borax, B4C granules, lead fiber, lead sand, iron sand, steel sand, or poured with lead, polyethylene, boron-containing polyethylene, or lead-boron polyethylene.

[0071] In order to achieve better shielding effect, the material between the innermost layer and the outermost layer of the container shield and the channel shield is selected from lead boron polyethylene, tungsten boron polyethylene, boron steel, alloy material X mH n -BW-Al or alloy material X m H n -B4C-W-Al, one or more of which X m H n For metal hydride.

[0072] If the channel shielding is composed of five layers of shielding bodies, the materials of the middle three layers of shielding bodies of the channel shielding are selected from lead boron polyethylene, tungsten boron polyethylene, boron steel, alloy material X m H n -BW-Al or alloy material X m H n -B4C-W-Al, one or more of which X m H n For metal hydride.

[0073] In this embodiment, the material of the container shield 311 and the channel shield intermediate layer shield 3123 is selected from lead boron polyethylene, tungsten boron polyethylene, boron steel, alloy material X m H n -BW-Al or alloy material X m H n -B4C-W-Al, one or more of which X m H n The channel shielding layers of the innermost shield 3122 and the outermost shield 3124 are made of carbon steel or stainless steel. This material selection allows for optimal radiation shielding during radioactive sampling operations in current nuclear power plants and reprocessing plants.

[0074] Through shielding calculation analysis, it is found that neutrons contribute more than 50% of the radiation to the front area of ​​the sampling cabinet. By adopting the above-mentioned shielding scheme in this application, a variety of shielding materials are combined in the shielding body, and the new composite shielding material is processed into a modular structure to further implement the internal shielding. The radiation of neutrons can be greatly reduced at an acceptable low cost. At the same time, the thickness of the sampling cabinet can be reduced by 10%-90%, and the weight can be reduced by 40%, effectively reducing the overall cost.

[0075] like Figure 3 As shown ( Figure 3 The operating robot, sealing air cover, and operating arm are not shown in the figure), the second-level shielding 32 at least covers the other surfaces of the device except the bottom surface, and the thickness of the second-level shielding 32 is 3mm-600mm. By limiting the thickness range and the coverage of the device by the shielding structure, the shielding performance of the device can be improved.

[0076] Specifically, the second-level shielding 32 includes a sampling cabinet shielding body 322 and a shielding window 321. Figure 3 It can be seen that the sampling cabinet shielding body 322 of the second-level shielding 32 adopts a three-layer shielding combination structure, including the innermost shielding body 3221 of the sampling cabinet shielding body, the middle shielding body 3222 of the sampling cabinet shielding body, and the outermost shielding body 3223 of the sampling cabinet shielding body.

[0077] Its manufacturing method is the same as that of the first-level shield 31. One or more layers of composite shielding material or neutron shielding material are installed on cast iron or a steel plate cabinet to reduce mixed radiation, strong neutron radiation and strong secondary radiation. The shielding materials and principles used are the same as those of the first-level shield 31, so they will not be repeated here.

[0078] To prevent radiation from directly penetrating the gaps, the sampling cabinet shield 322 can be staggered, or the innermost and outermost layers can be made of integral materials, with the middle layer cast, filled, or poured with solidifiable materials or block-shaped shielding materials.

[0079] In another embodiment of the present application, Figure 2 As shown, the innermost layer of the second-level shield 32 is further provided with a sealing air cover 5.

[0080] Specifically, the height of the sealing air hood 5 is not lower than the elevation of the upper surface of the material container 1 and the container shield 311, and the thickness is 0.3mm-20mm. It is made of radiation-resistant and easy-to-decontamination materials such as stainless steel, carbon fiber, fiberglass, and organic glass.

[0081] By providing a sealed air hood 5, the aerosol formed by the gaseous and volatile radioactive substances in the material container 1 can be effectively prevented from leaking out of the sealed air hood 5, thereby avoiding radioactive contamination inside the sampling cabinet shielding body 322. At the same time, it can prevent radioactive substances from leaking out of the sampling cabinet shielding body 322 to cause radioactive contamination and increase radiation to engineering personnel.

[0082] In addition, Figure 2 In the embodiment, the side wall of the second-stage shield 32 is penetrated by a manipulator 4, and there are two manipulators 4, which are respectively located on both sides of the shielding window 321. In other embodiments, the manipulators are located above or below the shielding window.

[0083] Specifically, the length of the operating manipulator 4 matches the size and position of the material container 1 and the container shielding 311, and can completely cover the area where the material container 1 is located, so that personnel can use the operating manipulator 4 through the shielding window 321 to perform sampling, moving, emptying, wiping and other related operations, thereby reducing the radiation to the body of engineering personnel.

[0084] In this embodiment, each side of the second-stage shield 32 is integrally formed and then assembled using one or more of bonding, welding, mortise and tenon joints, bolts, or pins. This integrally formed design reduces overall costs while minimizing the risk of radiation directly penetrating gaps. In other embodiments, multiple sides of the second-stage shield 32 are integrally formed at once.

[0085] In addition, the outermost layer of the second-stage shielding 32 is integrally formed, further reducing the radiation intensity.

[0086] The cross section of the sampling cabinet shield 322 can be rectangular or regular polygonal, and the best engineering form is square or rectangular.

[0087] In addition, according to the radiation type or radiation intensity of the radioactive sample, the shielding window 321 of the second-level shielding 32 of the present application adopts a combination of shielding window glasses made of multiple different materials, so as to utilize the shielding properties of each glass material and the shielding window glass combination structure to jointly shield the ionizing radiation of the radioactive sample.

[0088] The shielding window 321 is provided with four layers of glass, which are, from inside to outside, a first layer of glass 3211 of the shielding window, a second layer of glass 3212 of the shielding window, a third layer of glass 3213 of the shielding window, and a fourth layer of glass 3214 of the shielding window.

[0089] Among them, the first layer of glass 3211 of the shielding window is radiation-resistant glass or radiation-proof glass with radiation-resistant performance; the second layer of glass 3212 of the shielding window is radiation-proof glass or radiation-proof glass with radiation-resistant performance; the third layer of glass 3213 of the shielding window is radiation-proof glass; and the fourth layer of glass 3214 of the shielding window is protective glass.

[0090] Specifically, radiation-resistant glass includes but is not limited to K509 and K709; radiation-proof glass with radiation-resistant properties includes but is not limited to RS323-G19, RS253, RS360, and RS253-G18; radiation-proof glass can be divided into photon-shielding glass and neutron-shielding glass. Photon-shielding glass includes but is not limited to ZF501, ZF6, RS323-G19, and RS360; neutron-shielding glass includes but is not limited to RS253, RS253-G18, H-K9L, gadolinium-containing glass, boron-containing glass, and organic glass; comprehensive radiation-proof glass includes but is not limited to NF1 and RS323-G19; protective glass includes but is not limited to tempered glass and organic glass such as methyl methate.

[0091] To achieve good shielding effects, this application also provides corresponding thickness reference ranges for different types of shielding window glass. The thickness range for radiation-resistant glass is 5mm-500mm, the thickness range for radiation-resistant radiation-proof glass is 20mm-600mm, the thickness range for radiation-proof glass is 20mm-500mm, and the thickness range for protective glass is 3mm-100mm.

[0092] To ensure that the flatness and roughness of the glass surface meet the requirements, the outer surface of each layer of glass in the shielded window is treated by grinding and polishing, so that the different glass layers can be tightly spliced ​​during installation. During installation, direct tight splicing or bonding can be used to ensure that the cavitation between adjacent glass layers meets the requirements and the light transmittance is maintained at above 50%.

[0093] In order to avoid the existence of a direct through gap from the inside to the outside of the sampling cabinet, the cross-sectional dimension difference of each layer of glass in the shielding window needs to be within the range of 5mm-300mm.

[0094] In addition, the shielding window 321 includes a shielding window frame 3215. The gap between the shielding window frame 3215 and the shielding window glass and the sampling cabinet body does not exceed 10 mm, and is stepped from the inside to the outside of the sampling cabinet to avoid direct penetration gaps.

[0095] Specifically, the shielding window frame 3215 is made of carbon steel, stainless steel, alloy steel or other metals or alloys, and a sealant or sealing material is installed or filled in the gap between the shielding window frame 3215 and the sampling cabinet body.

[0096] Furthermore, the sampling cabinet shield 322 is mounted on the supporting body (e.g., a floor) using one or more of bonding, welding, mortise and tenon joints, bolts, or pins. The gap between the sampling cabinet shield 322 and the supporting body is no larger than 10 mm, and a sealant or sealing material is installed or filled in the gap.

[0097] The sampling cabinet shield 322 is designed for the radiation type of the radioactive sample. By utilizing a composite shielding structure composed of multiple materials and the interaction mechanism between the materials themselves and the radiation rays, the ionizing radiation of the radioactive sample is reduced to a specified level, and the exposure dose to the personnel operating and monitoring the sampling cabinet meets the dose limit requirements of GB18871.

[0098] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0099] 1. The present invention provides shielding bodies on the inner and outer layers of the device to reduce the external radiation intensity of the radioactive sample layer by layer. Even if the device is partially damaged, the external dose rate of the device can still be controlled within an acceptable range for radiation protection, thereby achieving higher safety.

[0100] 2. The present invention shields various types of ionizing radiation rays or particles, especially strong neutron radiation, mixed radiation and strong secondary radiation, by adjusting the parameters of container shielding, channel shielding, sampling cabinet shielding body and shielding window, such as material, size, shape, structure or combination form, so that the maximum dose rate outside the device does not exceed 10mSv / h, and has good comprehensive radiation protection and shielding performance.

[0101] 3. By adjusting the parameters of container shielding and channel shielding and selecting the optimal shielding material and structural combination, the present invention can significantly reduce the thickness and weight of the device while achieving the same radiation protection control indicators, while reducing the difficulty of lifting and installation, and improving the efficiency of transportation, lifting, installation and construction.

[0102] 4. The present invention installs shielding windows on the device for handling radioactive materials to provide effective radiation safety protection for workers, facilitate engineering personnel to operate, inspect and repair the device during operation, and reduce the difficulty of nuclear facility maintenance.

[0103] 5. The present invention provides an operating manipulator and an operating arm on the device for handling radioactive materials to assist workers in completing operations such as sampling, pouring materials, and moving samples, thereby effectively reducing the radiation intensity received by workers and further strengthening radiation safety.

[0104] 6. The present invention does not require additional compensating shielding materials and structures and corresponding supporting facilities or devices, can reduce the overall size and materials of nuclear facility shielding, increase space utilization, facilitate the layout and installation of systems and equipment in the space, eliminate unnecessary pipes and brackets, etc., and improve the overall economy of nuclear facility shielding.

[0105] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A device for processing radioactive materials, comprising a material container (1), a material channel (2) and a shielding structure (3), characterized in that: The shielding structure (3) includes a first-level shield (31) and a second-level shield (32), the second-level shield (32) is located outside the first-level shield (31), the first-level shield (31) includes a container shield (311) and a channel shield (312), the container shield (311) is provided outside the material container (1), the channel shield (312) at least partially surrounds the material channel (2) in the device, the outer periphery of the material channel (2) is completely surrounded by the shielding structure (3), and the second-level shield (32) includes a shielding window (321); The upper end of the material container (1) is not higher than the upper surface of the container shield (311), and the distance between the outer side surface of the material container (1) and the outer side surface of the container shield (311) in any direction is 5 cm-20 cm; The channel shield (312) is an integrally formed body made of the same material or a spliced ​​structure made of the same material, or is a channel shield layer made of 3-6 layers of different materials, the innermost and outermost channel shield layers are metal plates, and the thickness of the channel shield (312) is 5 cm-20 cm; The second-level shielding (32) comprises 2-6 layers of second-level shielding layers, the thickness of the second-level shielding (32) is 3mm-600mm, and the second-level shielding layer at least covers the other surfaces of the device except the bottom surface.

2. The device for treating radioactive materials according to claim 1, characterized in that: The shielding materials of the first-level shield (31) and the second-level shield (32) are different.

3. The device for treating radioactive materials according to claim 1, characterized in that: An operating arm (6) is provided on the container shield (311), and the operating arm (6) can be rotated to different material container (1) positions for operating the material or the material container (1).

4. The device for treating radioactive materials according to claim 3, characterized in that: The material of the container shield (311) and the channel shield (312) includes neutron shielding material.

5. The device for treating radioactive materials according to claim 4, characterized in that: The material between the innermost layer and the outermost layer of the channel shield and the material of the container shield are selected from lead boron polyethylene, tungsten boron polyethylene, boron steel, alloy material X m H n -BW-Al or alloy material X m H n -B4C-W-Al, one or more of which X m H n The channel shield (312) is a hydrogenated metal, and the innermost layer and the outermost layer of the channel shield are carbon steel or stainless steel.

6. The device for treating radioactive materials according to claim 5, characterized in that: A metal partition is provided between the channel shielding layers, and the thickness of the metal partition is 1 mm to 50 mm.

7. The device for treating radioactive materials according to claim 1, characterized in that: The second-level shield (32) includes a plurality of surfaces, the plurality of surfaces are integrally formed, or each of the plurality of surfaces is integrally formed.

8. The device for treating radioactive materials according to claim 1, characterized in that: An operating manipulator (4) is provided through the front side wall of the second-level shield (32), and there are two operating manipulators (4). The operating manipulators (4) are located above or below the shielding window (321), or the operating manipulators (4) are located on both sides of the shielding window (321).

9. The device for treating radioactive materials according to claim 8, characterized in that: The length of the operating manipulator (4) matches the size and position of the material container (1) and the container shield (311), completely covering the area where the material container (1) is located.

10. The device for treating radioactive materials according to claim 9, characterized in that: The inner layer of the second-stage shield (32) is provided with a sealing air hood (5), the height of the sealing air hood (5) is not lower than the elevation of the upper surface of the material container (1) and the container shield (311), and the thickness is 0.3 mm-20 mm.

11. The device for treating radioactive materials according to claim 1, characterized in that: The shielding window (321) comprises 2 to 6 shielding window layers made of different materials, and the outermost shielding window layer is protective glass.

12. The device for treating radioactive materials according to claim 11, characterized in that: The innermost layer of the shielding window layer of the shielding window (321) is radiation-resistant glass, and at least one layer of the shielding window layer of the shielding window (321) is radiation-proof glass.

13. The device for treating radioactive materials according to claim 11, characterized in that: The shielding window (321) comprises a shielding window frame (3215), the shielding window frame (3215) is arranged in a stepped shape from the inside to the outside, and the shielding window frame (3215) is made of metal.

14. The device for treating radioactive materials according to any one of claims 1 to 12, characterized in that: The device for processing radioactive materials is a radioactive sampling cabinet.

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