Target material arrangement device suitable for researching reactor irradiation production of iridium-192

Abstract

The invention relates to the technical field of isotope irradiation production, in particular to a target material arrangement device suitable for researching reactor irradiation production of iride-192. The target material arrangement device mainly comprises a cladding, a plurality of clamping blocks and iridium sheets, the clamping blocks are arranged on the inner side of the cladding and arranged around the circumference of the central axis of the cladding, and the iridium sheets are arranged on the clamping blocks; and the iridium sheet is arranged on one side, in contact with the cladding, of the clamping block. Through the structure, the target material in the target material arrangement mode of the iride-192 is designed into a pure I < r > circular sheet. The small-size target material can improve the irradiation uniformity of a single target material and can be used for manufacturing a small-size flaw detection source device, and the application range of a product is widened. The target material is defined as a natural target material and a high-enrichment-degree target material according to the difference of the content of the iridium 191 in the target material, the target material arrangement can be automatically adjusted according to the actual production requirement, and the production flexibility of the iridium 192 can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of isotope irradiation production, and in particular to a target material arrangement device suitable for producing iridium-192 by irradiation in a research reactor. Background Art

[0002] Iridium is a Group VIII transition metal element, with a content of one part in ten million in the earth's crust. There are two isotopes in nature, iridium-191 and iridium-193. The artificial radioactive isotope iridium-192 is obtained by neutron radiation of the stable element iridium-191, and is commonly used in radiotherapy, industry, scientific research and other fields.

[0003] Iridium-192 is widely used in the field of radiotherapy, acting on intracavitary tumors, and can be used to treat cervical cancer, prostate cancer, lung cancer and many other cancers. In radiotherapy, iridium-192 is usually injected or implanted into tumor tissue in the form of seeds or needles of various shapes. The radioactive decay of iridium-192 can directly destroy cancer cells and reduce the size and volume of tumors.

[0004] Iridium-192 is widely used in the industrial field for non-destructive testing. Industrial non-destructive testing is a method used to detect internal defects or foreign matter in materials, such as metal welded joints, pipes and tanks. In non-destructive testing, the iridium-192 radioactive source can be irradiated through the object, and then the reflection and absorption of the radiation are detected by the detection equipment to determine the defects in the material. Due to the moderate radiation energy of iridium-192 and the high specific activity of the radioactive source, it can be made into a point source greater than 3.7TBq, which is suitable for gamma radiography of most metal materials. However, the current production of iridium-192 in existing technologies is relatively low. Summary of the invention

[0005] The purpose of the present invention is to provide a target arrangement device suitable for producing iridium-192 by irradiation in a research reactor, so as to solve the above-mentioned problems in the prior art.

[0006] The present invention is achieved through the following technical solutions:

[0007] A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor comprises a cladding, a plurality of clamping blocks and an iridium sheet. The clamping blocks are arranged on the inner side of the cladding and are arranged circumferentially around the central axis of the cladding. The iridium sheet is arranged on the side of the clamping blocks that contacts the cladding.

[0008] Preferably, a first groove is formed at one side of the clamping block, and the iridium sheet is arranged in the first groove.

[0009] Preferably, a second groove is provided on one side of the clamping block along the length direction of the clamping block, and a protrusion is provided on the inner side of the enclosure, and the protrusion is embedded and connected with the second groove.

[0010] Preferably, a side surface of the clamping block away from the enclosure is configured to be a concave arc.

[0011] Preferably, four clamping blocks are provided.

[0012] Preferably, the inner diameter of the cladding is 0.8 cm and the outer diameter is 1 cm.

[0013] Preferably, the depth of the first groove is greater than or equal to 0.2 mm.

[0014] Preferably, the included angle between the two side surfaces of the clamping block adjacent to the second groove is 80 degrees.

[0015] Preferably, the interval between the upper and lower adjacent iridium sheets is 5 cm.

[0016] Preferably, a plurality of the clamping blocks are arranged in a circle on a side away from the enclosure.

[0017] The technical solution of the present invention has at least the following advantages and beneficial effects:

[0018] The structure provided by the present invention mainly includes a cladding, a plurality of clamping blocks and an iridium sheet. The clamping blocks are arranged on the inner side of the cladding and are arranged circumferentially around the central axis of the cladding. The iridium sheet is arranged on the clamping blocks on the side in contact with the cladding. Through the above structure, the target material in the target material arrangement method of iridium-192 is designed as a pure Ir circular thin sheet. Small-sized targets can improve the irradiation uniformity of a single target material, and can be used to make small-sized flaw detection source devices, increasing the scope of application of the product. According to the different iridium-191 contents in the target material, they are defined as natural targets and high-enrichment targets respectively. The target material arrangement can be adjusted independently according to actual production needs, which is conducive to improving the production flexibility of iridium-192. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a structural schematic diagram of the clamping block of the present invention.

[0022] Icon: 1-clamp, 2-cladding, 3-iridium sheet. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0024] Please refer to Figure 1-Figure 2 The present invention provides a target arrangement device suitable for producing iridium-192 by irradiation in a research reactor, comprising a cladding 2, a plurality of clamping blocks 1 and an iridium sheet 3. The clamping blocks 1 are arranged on the inner side of the cladding 2 and are arranged around the central axis of the cladding 2. The iridium sheet 3 is arranged on the clamping blocks 1 on the side in contact with the cladding 2.

[0025] Specifically, the cross-section of the clamp block 1 is in a fan-shaped shape, a first groove begins to be formed on one side of the clamp block 1, the iridium sheet 3 is arranged in the first groove, the side of the clamp block 1 away from the cladding 2 is arranged to be a concave arc, and the side adjacent to the cladding 2 is arranged to be a convex arc. In the present embodiment, a total of four clamp blocks 1 are arranged.

[0026] A second groove is provided on one side of the clamping block 1 along the length direction of the clamping block 1 , and a protrusion is provided on the inner side of the enclosure 2 , and the protrusion is inlaid and connected with the second groove.

[0027] In an exemplary embodiment of the present invention, the inner diameter of the cladding 2 is 0.8 cm, the outer diameter is 1 cm, the depth of the first groove is greater than or equal to 0.2 mm, the angle between the two side surfaces of the clamping block 1 adjacent to the second groove is 80 degrees, the interval between the upper and lower adjacent iridium sheets 3 is 5 cm, and a plurality of clamping blocks 1 are arranged in a circle away from the side surface of the cladding 2.

[0028] Secondly, the structure provided by the present invention can be used to manufacture a small-sized flaw detection source device. It is also applicable to high-enrichment target materials and natural-enrichment target materials, and the target material layout can be adjusted independently according to actual production needs, which is conducive to improving the production flexibility of iridium-192.

[0029] The above structure determines that the target is arranged vertically, which can effectively reduce the irradiation unevenness of a single target; the radial and longitudinal arrangement intervals of the target are determined, which can effectively avoid the reduction of product activity due to too dense arrangement of the target; the arrangement height range of the target is determined, which can effectively improve the product output and qualified rate of a single irradiation; the positioning method and fixing method of the target are determined, which can effectively improve the qualified rate and safety of a single irradiation.

[0030] The target arrangement mode for producing iridium-192 by irradiation in a research reactor proposed by the present invention should be arranged oppositely to expand the spacing of single-layer targets. The target should be fixed by the cladding 2 and the clamping block 1. Considering that the target may swell after being irradiated, sufficient gap should be reserved for placing the target.

[0031] The radial and longitudinal spacing between the targets is achieved by adopting the design of the special-shaped clamp block 1, so as to avoid a large decrease in the local neutron injection rate due to the target materials being arranged too close, thereby reducing the yield and specific activity of the target product iridium-192.

[0032] This includes selecting the irradiation height based on the actual active section height under study to avoid the target material layout height deviating too much from the active section, resulting in too low a neutron injection rate, which makes it difficult to meet the specific activity requirements of the target product iridium-192 after the same irradiation time period.

[0033] In a specific embodiment:

[0034] Example: Taking high-throughput research reactor as the application object, a target material arrangement method for irradiating iridium-192 is designed according to the present invention. The target material is designed as a pure Ir circular thin sheet, a single small sample has a diameter of 2.7 mm, a thickness of 0.15 mm, and a single small sample weighs about 0.02 g.

[0035] Arrange 4 targets in a single layer, and set the minimum spacing between the cladding 2 and the clamp block 1 to 0.2mm for placing the targets. The aluminum clamp block 1 is a special-shaped cylinder with a central hole. The inner diameter of the clamp block 1 is 0.4cm and the outer diameter is 0.8cm. The internal central hole is filled with helium. The aluminum cladding 2 is a special-shaped cylinder with a central hole. The inner diameter of the cladding 2 is 0.8cm and the outer diameter is 1.0cm. The clamp block 1 and the cladding 2 play the role of positioning and fixing the target together, and the composition is 6061 aluminum alloy. The active section of the high-throughput research reactor is 1000mm long, and the designed target irradiation length is 400mm. It is placed at a height of 300-700mm in the active section (starting from the bottom of the active area). The design of the special-shaped clamp block 1 is used to achieve the radial and longitudinal spacing between the targets. The radial spacing is 7mm and the longitudinal spacing is 2.3mm. A total of 86 target arrangement layers are designed, and a total of 344 targets can be loaded, totaling 6.88g.

[0036] The production calculation is carried out by using the hole K10 in the central fuel element of HFETR, and the calculation results are as follows:

[0037] Table 1 Calculation results of 192I r radioactivity specific activity of irradiated products

[0038]

[0039] Table 2 Calculation results of 192I r radioactivity specific activity of irradiated products

[0040]

[0041] After calculation, after adopting the target arrangement method of the present invention, when enriched target material is used for irradiation production of iridium-192, the average specific activity of iridium-192 is increased from 739 Ci / g to 1284 Ci / g; when natural target material is used for irradiation production of iridium-192, the average specific activity of iridium-192 is increased from 405 Ci / g to 739 Ci / g, indicating that the target arrangement method can effectively increase the yield of iridium-192.

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor, characterized in that: The invention comprises a cladding (2), a plurality of clamping blocks (1) and an iridium sheet (3), wherein the clamping block (1) is arranged on the inner side of the cladding (2) and is arranged circumferentially around the central axis of the cladding (2), and the iridium sheet (3) is arranged on the side of the clamping block (1) that is in contact with the cladding (2).

2. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 1, characterized in that: A first groove is formed at one side of the clamping block (1), and the iridium sheet (3) is arranged in the first groove.

3. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 2, characterized in that: A second groove is provided on one side of the clamping block (1) along the length direction of the clamping block (1), and a protrusion is provided on the inner side of the enclosure (2), and the protrusion is embedded and connected with the second groove.

4. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 3, characterized in that: A side surface of the clamping block (1) away from the enclosure (2) is arranged to be in a concave arc shape.

5. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 4, characterized in that: Four clamping blocks (1) are provided.

6. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 5, characterized in that: The inner diameter of the cladding (2) is 0.8 cm, and the outer diameter is 1 cm.

7. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 6, characterized in that: The depth of the first groove is greater than or equal to 0.2 mm.

8. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 7, characterized in that: The included angle between the two side surfaces of the clamping block (1) adjacent to the second groove is 80 degrees.

9. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 8, characterized in that: The interval between the upper and lower adjacent iridium sheets (3) is 5 cm.

10. A target arrangement device suitable for producing iridium-192 by irradiation in a research reactor according to claim 9, characterized in that: A plurality of the clamping blocks (1) are arranged in a circle on a side away from the enclosure (2).

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