Mo-99 and Mo-99 production device integrated into the bio-shielding layer of fusion reactor

Abstract

This application discloses Mo-99 and a Mo-99 production device integrated into a fusion reactor's biological shielding layer. The production device includes: neutrons generated by plasma; a functional wall for absorbing neutrons; and, in the direction from top to bottom along the neutron jet path, a production functional layer containing at least one sealed fluid channel. The fluid channel contains microcapsules and a flowing working fluid, with the working fluid located on both sides of the microcapsules in the direction of the fluid channel's extension. Each microcapsule includes a core material and an aluminum shell covering the core material, the core material being a Mo-100 solid target core; a neutron absorption layer; and a biological shielding layer. This allows for the integration of isotope production and radiation protection functions, enhancing the local protection capability of the biological shielding layer while achieving efficient resource utilization of escaping neutrons.

Description

Technical Field

[0001] This application relates to the field of nuclear technology applications, specifically to Mo-99 and a Mo-99 production device integrated into the biological shielding layer of a fusion reactor. Background Technology

[0002] Molybdenum-99 ( 99 Mo) as a medical radioactive isotope technetium-99m ( 99m The parent compound of Tc is the most widely used radiopharmaceutical precursor in the global field of nuclear medicine diagnostics. Currently, 99 Commercial production of molybdenum (Mo) primarily relies on the fission reaction of highly enriched uranium (HEU) or low-enriched uranium (LEU) targets in research reactors. However, this traditional approach has significant drawbacks: first, it depends on aging research reactor facilities, leading to a fragile global supply chain and frequent supply shortages; second, the use of uranium materials introduces nuclear proliferation risks and the challenge of disposing of long-lived high-level radioactive waste; and third, the fission products are complex in composition, and even after purification, trace impurities still exist. 99m Tc generator performance.

[0003] It should be noted that the above statements are only used to provide background information related to this application and do not necessarily constitute prior art. Summary of the Invention

[0004] In a first aspect of this application, a Mo-99 production device integrated into the bio-shielding layer of a fusion reactor is proposed, comprising:

[0005] Neutrons, which are produced by plasma;

[0006] A functional wall, the functional wall being used to absorb the neutrons, comprising, in the direction from top to bottom along the neutron jet path:

[0007] The production functional layer includes at least one sealed fluid channel, the fluid channel contains microcapsules and a flowing working medium, the flowing working medium is located on both sides of the microcapsule in the extending direction of the fluid channel, the microcapsule includes a core material and an aluminum shell covering the core material, the core material includes a Mo-100 solid target core;

[0008] A neutron-absorbing layer is located on one side of the production functional layer;

[0009] A biological shielding layer is located on the side of the neutron absorption layer away from the production functional layer.

[0010] The Mo-99 production device integrated into the bio-shielding layer of the fusion reactor described in this application has at least the following beneficial effects:

[0011] (1) The 14.1 MeV high-energy neutrons that are traditionally wasted by being absorbed by biological shielding layers are directly converted into high-value medical isotopes in this application. 99 Mo's driving force not only improves the comprehensive utilization efficiency of neutron resources in fusion reactors, but also transforms radiation sources that originally needed protection into economic assets, realizing the added value of nuclear energy systems.

[0012] (2) By integrating the isotope production functional layer onto the surface of the neutron absorption layer and the biological shielding layer, the isotope production function and radiation protection function are combined into one. This integrated design does not require additional cladding space or additional external equipment, which greatly simplifies the system structure, reduces interface complexity and construction cost, and provides convenience for the modular deployment of future fusion power plants.

[0013] (3) This application is based on 100 Mo(n,2n) 99 The Mo reaction, which does not use any uranium material, fundamentally avoids the risks of nuclear proliferation and the problem of long-lived high-level radioactive waste. Simultaneously, this reaction naturally produces carrier-free (NCA), meeting the high specific activity requirements of advanced nuclear medicine. 99 Mo's needs;

[0014] (4) The multi-layered structure of the functional wall ensures that high-energy neutrons can effectively penetrate the target area to drive the (n,2n) reaction, while also efficiently capturing secondary thermal neutrons and shielding gamma rays. This maximizes... 99 While increasing Mo production, the radiation dose outside the functional walls is strictly controlled within safe limits to ensure the safety of operation and maintenance personnel.

[0015] In some embodiments, the working fluid includes water or an inert gas. Thus, after a preset irradiation time, the working fluid is used to rapidly eject the microcapsules from the high-flux irradiation zone, enabling the online removal and replacement of the product Mo-99.

[0016] In some embodiments, the fluid channel is made of at least one of aluminum, zirconium, and 316L stainless steel. This allows for minimizing neutron flux loss while ensuring structural strength, and maximizing the utilization of activation products (such as...). 28 Al) degrades to a level that is safe to maintain within one hour after shutdown.

[0017] In some embodiments, the inner diameter of the fluid channel is 0.15 cm to 0.3 cm, and the outer diameter is 0.3 cm to 0.45 cm. This facilitates neutron penetration of the fluid channel wall, thereby enabling it to react with the Mo-100 solid target core to produce the medical isotope Mo-99.

[0018] In some embodiments, the microcapsule is cylindrical, with chamfered or helicaled ends. This facilitates pneumatic propulsion and robotic gripping, and helps to eject the microcapsule from the fluid channel.

[0019] In some embodiments, the thickness of the aluminum shell is 0.002 cm to 0.1 cm. Thus, the aluminum shell is used to seal the Mo-100 solid target core while also providing structural support.

[0020] In some embodiments, the neutron absorbing layer comprises a boron-containing material and / or a gadolinium-containing material. Thus, the neutron absorbing layer can efficiently capture thermal neutrons and secondary neutrons transmitted from the production functional layer, reducing neutron leakage.

[0021] In some embodiments, the boron-containing material includes at least one of boronized polyethylene and boron steel, and the gadolinium-containing material includes at least one of gadolinium-containing stainless steel and gadolinium-boron polyethylene. Thus, the neutron absorbing layer can efficiently capture thermal neutrons and secondary neutrons transmitted from the production functional layer, reducing neutron leakage.

[0022] In some embodiments, the bio-shielding layer comprises heavy concrete or a steel-lead composite material. This allows for shielding against [the effects of] [the contamination from] [other sources]. 99 The gamma rays generated by Mo decay and structural activation, along with the remaining neutrons, ensure that the external radiation dose rate of the wall meets safety standards.

[0023] In some embodiments, the thickness of the neutron absorbing layer is 15 cm to 30 cm. This facilitates efficient absorption of thermal neutrons.

[0024] In some embodiments, the thickness of the biological shielding layer is 2m to 4m. This is beneficial for shielding unabsorbed neutrons and the accompanying gamma rays.

[0025] In a second aspect of this application, a Mo-99 is proposed, obtained using the Mo-99 production apparatus described in the first aspect of this application. This Mo-99 exhibits a high specific activity, meeting the demand for novel, highly specific radiopharmaceuticals. Attached Figure Description

[0026] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein,

[0027] Figure 1 This is a schematic cross-sectional view of the functional wall structure of a Mo-99 production device integrated into a fusion reactor bio-shielding layer according to an embodiment of this application.

[0028] Figure 2This is a schematic cross-sectional view of the fluid channel in a Mo-99 production device integrated into a fusion reactor bio-shielding layer according to an embodiment of this application.

[0029] Figure 3 This is a schematic diagram of neutron transport calculation in this application.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1-Production functional layer, 2-Neutral absorption layer, 3-Bio-shielding layer, 4-Air, 5-Fluid channel, 6-Microcapsule, 7-Flowing working fluid. Detailed Implementation

[0032] The embodiments of this application are described in detail below, with examples of these embodiments shown in the accompanying drawings. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0033] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit this application; unless otherwise stated, the values ​​of the parameters mentioned in this application can be measured using various measurement methods commonly used in the art (e.g., they can be tested according to the methods given in the embodiments of this application).

[0034] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are open-ended expressions, meaning they include what is specified in this application but do not exclude other aspects.

[0035] In the description of this application, all figures disclosed herein, whether or not the words "approximately" or "about" are used, are approximate values. Each figure may vary by less than 10% or by a difference that is considered reasonable by one of the art, such as 1%, 2%, 3%, 4%, or 5%.

[0036] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for a specific parameter, it is also expected that ranges of 60~110 and 80~120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this application, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0037] In the description of this application, "A and / or B" can include any of the cases of A alone, B alone, or A and B, where A and B are merely examples and can be any technical feature connected by "and / or" in this application.

[0038] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0039] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0040] During operation, deuterium-tritium fusion reactors continuously produce high-energy 14 MeV neutrons, which are the key source of energy production and tritium breeding. While the breding blanket and vacuum vessel constitute the main neutron shielding and moderation system within the reactor structure, unavoidable assembly gaps, cooling pipe penetrations, and various diagnostic ports, along with the inherently high-flux neutron environment of the fusion reactor, mean that some fast neutrons can still escape to the outermost biological shielding layer. This results in localized areas of the biological shielding layer being exposed to high-flux fast neutron irradiation for extended periods, facing serious risks of activation and material degradation.

[0041] Traditional radiation protection designs typically employ passive protection strategies, such as simply increasing shielding thickness or using high-performance shielding materials. While these strategies can mitigate leakage problems, they do not effectively utilize escaping neutrons. To address these issues, this application proposes a novel neutron utilization-shielding composite device that enhances the local protection capabilities of biological shielding layers while simultaneously achieving efficient resource utilization of escaping neutrons.

[0042] In a first aspect of this application, a Mo-99 production device integrated into the bio-shielding layer of a fusion reactor is proposed, comprising:

[0043] Neutrons, which are produced by plasma;

[0044] Functional wall, the functional wall being used to absorb the neutrons in the direction from top to bottom of the neutron jet path (i.e., Figure 1 (neutron incident direction in the middle), refer to Figure 1 The functional wall includes:

[0045] Production functional layer 1, wherein the production functional layer 1 includes at least one sealed fluid channel in which microcapsules circulate, as shown in the reference. Figure 2 The fluid channel 5 includes microcapsules 6 and a flowing working medium 7 inside. In the extending direction of the fluid channel 5, the flowing working medium 7 is located on both sides of the microcapsules 6. The microcapsules 6 include a core material and an aluminum shell covering the core material. The core material includes a Mo-100 solid target core. The production functional layer 1 is supported by a biological shielding layer 3, and the functional wall is surrounded by air 4.

[0046] Neutron absorbing layer 2, which is located on one side of the production functional layer 1;

[0047] A biological shielding layer 3 is located on the side of the neutron absorption layer 2 away from the production functional layer 1.

[0048] The Mo-99 production device integrated into the bio-shielding layer of the fusion reactor described in this application has at least the following beneficial effects:

[0049] (1) The 14.1 MeV high-energy neutrons that are traditionally wasted by being absorbed by biological shielding layers are directly converted into high-value medical isotopes in this application. 99 Mo's driving force not only improves the comprehensive utilization efficiency of neutron resources in fusion reactors, but also transforms radiation sources that originally needed protection into economic assets, realizing the added value of nuclear energy systems.

[0050] (2) By integrating the isotope production functional layer onto the surface of the neutron absorption layer and the biological shielding layer, the isotope production function and radiation protection function are combined into one. This integrated design does not require additional cladding space or additional external equipment, which greatly simplifies the system structure, reduces interface complexity and construction cost, and provides convenience for the modular deployment of future fusion power plants.

[0051] (3) This application is based on 100 Mo(n,2n) 99 The Mo reaction, which does not use any uranium material, fundamentally avoids the risks of nuclear proliferation and the problem of long-lived high-level radioactive waste. Simultaneously, this reaction naturally produces carrier-free (NCA), meeting the high specific activity requirements of advanced nuclear medicine. 99 Mo's urgent needs;

[0052] (4) The multi-layered structure of the functional wall ensures that high-energy neutrons can effectively penetrate the target area to drive the (n,2n) reaction, while also efficiently capturing secondary thermal neutrons and shielding gamma rays. This maximizes... 99 While increasing Mo production, the radiation dose outside the functional walls is strictly controlled within safe limits to ensure the safety of operation and maintenance personnel.

[0053] In this application, the operating principle of the Mo-99 production device is as follows: 14.1 MeV neutrons generated during fusion reactor operation pass through the first wall and the blanket, with some neutrons leaking into the biologically shielded area. The functional wall in this application is located in this high-energy neutron flux region. Neutrons penetrate the fluid channel wall and interact with the fluid within the channel. 100 Mo nuclei undergo an (n, 2n) reaction, generating high-specific-activity radionuclides online. 99 Mo. After a set irradiation cycle, the microcapsules can be carried out by a flowing working medium, and the contents can be extracted. 99 Mo. Meanwhile, the multi-layered structure of the functional wall itself gives it excellent self-shielding properties.

[0054] It is understandable that this Mo-99 production device possesses good scalability and compatibility, and can be flexibly adapted to fusion devices of different scales (such as the International Thermonuclear Experimental Reactor (ITER), the China Fusion Engineering Test Reactor (CFEDR), or commercial reactors). By adjusting the area of ​​the functional walls and the flow rate of the microcapsules, it can be adjusted as needed. 99 Mo production is expected to meet the regional and even national demand for medical isotopes, contributing to solving the global demand for these isotopes. 99 Mo provides solutions to supply chain vulnerability issues.

[0055] In some embodiments, the Mo-99 production apparatus further includes a vacuum chamber, which isolates the complex gaseous environment of the Earth's atmosphere, providing an independent and pure vacuum electromagnetic chamber for the fusion plasma and its working gas, where neutrons are generated by the plasma. Functional walls are spaced around the vacuum chamber. It is understood that the functional walls are typically several meters away from the vacuum chamber, separated by Dewar flares, cryogenic shields, maintenance spaces, etc. Thus, the functional walls can absorb neutrons escaping from the vacuum chamber and utilize these neutrons to produce the medical isotope Mo-99.

[0056] In some embodiments, the working fluid includes water or an inert gas. Thus, after a preset irradiation time, the working fluid is used to rapidly eject the microcapsules from the high-flux irradiation zone, enabling the online removal and replacement of the product Mo-99.

[0057] In some embodiments, the fluid channel is made of at least one of aluminum, zirconium, and 316L stainless steel. This allows for minimizing neutron flux loss while ensuring structural strength, and maximizing the utilization of activation products (such as...). 28 Al) degrades to a level that is safe to maintain within one hour after shutdown.

[0058] In some embodiments, the inner diameter of the fluid channel is 0.15cm to 0.3cm (e.g., 0.15cm, 0.17cm, 0.19cm, 0.21cm, 0.23cm, 0.25cm, 0.27cm, 0.29cm, or 0.3cm), and the outer diameter is 0.3cm to 0.45cm (e.g., 0.3cm, 0.32cm, 0.34cm, 0.36cm, 0.38cm, 0.4cm, 0.42cm, 0.44cm, or 0.45cm). It can be understood that the outer diameter of the fluid channel is the thickness of the functional layer. This facilitates neutron penetration of the fluid channel wall, thereby reacting with the Mo-100 solid target core to produce the medical isotope Mo-99.

[0059] In some embodiments, the microcapsule is cylindrical, with chamfered or helicaled ends. This facilitates pneumatic propulsion and robotic gripping, and helps to eject the microcapsule from the fluid channel.

[0060] In some embodiments, the thickness of the aluminum shell is 0.002 cm to 0.1 cm, for example, it can be 0.002 cm, 0.005 cm, 0.008 cm, 0.01 cm, 0.02 cm, 0.04 cm, 0.06 cm, 0.08 cm, or 0.1 cm. Thus, the aluminum shell is used to seal the Mo-100 solid target core and also provides some structural support.

[0061] In some embodiments, the neutron absorbing layer comprises a boron-containing material and / or a gadolinium-containing material. Thus, the neutron absorbing layer can efficiently capture thermal neutrons and secondary neutrons transmitted from the production functional layer, reducing neutron leakage.

[0062] In some embodiments, the boron-containing material includes at least one of boronized polyethylene (BPE) and boron steel, and the gadolinium-containing material includes at least one of gadolinium-containing stainless steel and gadolinium-boron polyethylene. The hydrogen in the boron-containing polyethylene moderates leaking neutrons, while boron (typically added in the form of B4C) efficiently absorbs thermal neutrons. Thus, the neutron-absorbing layer can efficiently capture thermal and secondary neutrons transmitted from the production functional layer, reducing neutron leakage.

[0063] In some embodiments, the bio-shielding layer comprises heavy concrete or a steel-lead composite material. This allows for shielding against [the effects of] [the contamination from] [other sources]. 99 The gamma rays generated by Mo decay and structural activation, along with the remaining neutrons, ensure that the external radiation dose rate of the wall meets safety standards.

[0064] In some embodiments, the thickness of the neutron absorbing layer is 15cm to 30cm, for example, it can be 15cm, 17cm, 19cm, 21cm, 23cm, 25cm, 27cm or 30cm, etc. This is beneficial for the efficient absorption of thermal neutrons.

[0065] In some embodiments, the thickness of the biological shielding layer is 2m to 4m, for example, it can be 2m, 2.5m, 3m, 3.5m, or 4m. This is beneficial for shielding unabsorbed neutrons and the accompanying gamma rays.

[0066] It should be noted that all geometric parameters (such as the specific thickness of the neutron absorption layer and the biological shielding layer) involved in the Mo-99 production device integrated into the fusion reactor biological shielding layer of this application can be adjusted according to the actual fusion reactor operating power, external radiation dose limit, and the size of the high-energy neutron leakage region.

[0067] In a second aspect of this application, a Mo-99 is proposed, obtained using the Mo-99 production apparatus described in the first aspect of this application. This Mo-99 exhibits a high specific activity, meeting the demand for novel, highly specific radiopharmaceuticals.

[0068] The description of the various embodiments above tends to emphasize the differences between the various embodiments. The similarities or similarities between them can be referred to, and for the sake of brevity, they will not be repeated here.

[0069] The following specific embodiments illustrate the solution of this application. It should be noted that these embodiments are for illustrative purposes only and should not be considered as limiting the scope of this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0070] Example 1

[0071] A Mo-99 production device integrated into the bio-shielding layer of a fusion reactor, referring to Figure 1 and Figure 2 ,include:

[0072] Neutrons are produced by plasma.

[0073] Functional walls, used to absorb neutrons, include the following components along the top-to-bottom direction of the neutron jet path:

[0074] The production functional layer 1 includes a sealed fluid channel in which microcapsules circulate. The fluid channel is made of aluminum, with an inner diameter of 0.3 cm and an outer diameter of 0.45 cm. The fluid channel 5 contains microcapsules 6 and a flowing working medium 7. The flowing working medium is located on both sides of the microcapsules in the extension direction of the fluid channel. The microcapsules include a core material and an aluminum shell covering the core material. The thickness of the aluminum shell is 0.002 cm, and the core material is a Mo-100 solid target core.

[0075] Neutron absorbing layer 2 is located on one side of the production functional layer. The neutron absorbing layer is made of boronized polyethylene and has a thickness of 15cm.

[0076] Biological shielding layer 3 is located on the side of the neutron absorption layer away from the production function layer. The biological shielding layer is made of heavy concrete and has a thickness of 2m.

[0077] This application utilizes the aforementioned device to convert high-energy neutrons, which would otherwise require shielding, into a resource for producing high-value medical isotopes, providing a safe, efficient, and sustainable method. 99 New avenues for Mo supply. Figure 3 This diagram illustrates the neutron transport calculations of this application, showing the shielding capability of the functional wall in a 14 MeV uniform neutron irradiation field. It demonstrates that the functional wall of this application can effectively shield neutrons. Monte Carlo calculations based on a uniform DT neutron source (14.1 MeV) irradiation field show that, on average, approximately 1.345 × 10⁻¹⁰ neutrons are generated per second per incident neutron per unit volume. -6 indivual 99 Mo atom, that is 99 The yield of Mo is 1.345 × 10-6 / (cm 3 ·s·n).

[0078] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A Mo-99 production device integrated into the biological shielding layer of a fusion reactor, characterized in that, include: Neutrons, which are produced by plasma; A functional wall, the functional wall being used to absorb the neutrons, comprising, in the direction from top to bottom along the neutron jet path: The production functional layer includes at least one sealed fluid channel, the fluid channel contains microcapsules and a flowing working medium, the flowing working medium is located on both sides of the microcapsule in the extending direction of the fluid channel, the microcapsule includes a core material and an aluminum shell covering the core material, the core material includes a Mo-100 solid target core; A neutron-absorbing layer is located on one side of the production functional layer; A biological shielding layer is located on the side of the neutron absorption layer away from the production functional layer.

2. The Mo-99 production apparatus according to claim 1, characterized in that, The working fluid includes water or an inert gas.

3. The Mo-99 production apparatus according to claim 1 or 2, characterized in that, The fluid channel is made of at least one of aluminum, zirconium, and 316L stainless steel; and / or, The fluid channel has an inner diameter of 0.15cm to 0.3cm and an outer diameter of 0.3cm to 0.45cm.

4. The Mo-99 production apparatus according to claim 1 or 2, characterized in that, The microcapsule is cylindrical, and both ends of the microcapsule are provided with chamfers or spiral patterns.

5. The Mo-99 production apparatus according to claim 1 or 2, characterized in that, The thickness of the aluminum shell is 0.002cm to 0.1cm.

6. The Mo-99 production apparatus according to claim 1 or 2, characterized in that, The neutron absorption layer comprises boron-containing materials and / or gadolinium-containing materials.

7. The Mo-99 production apparatus according to claim 6, characterized in that, The boron-containing material includes at least one of boronized polyethylene and boron steel, and the gadolinium-containing material includes at least one of gadolinium-containing stainless steel and gadolinium-boron polyethylene.

8. The Mo-99 production apparatus according to claim 1 or 2, characterized in that, The biological shielding layer comprises heavy concrete or a steel-lead composite material.

9. The Mo-99 production apparatus according to claim 8, characterized in that, The thickness of the neutron absorption layer is 15cm to 30cm.

10. The Mo-99 production apparatus according to claim 8, characterized in that, The thickness of the biological shielding layer is 2m to 4m.

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