Material composition analysis system
Patent Information
- Application Number
- PCT/CN2026/093650
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-04-15
- Filing Date
- 2026-04-28
- Publication Date
- 2026-10-22
Smart Images
Figure CN2026093650_22102026_PF_FP_ABST
Abstract
Description
Material composition analysis system
[0001] Cross-references to related applications
[0002] This application is based on CN application number 202510470774.9, filed on April 15, 2025, and claims priority to it. The disclosure of that CN application is incorporated herein by reference in its entirety. Technical Field
[0003] This disclosure relates to material analysis techniques, and in particular to a material composition analysis system. Background Technology
[0004] In some related technologies of material analysis equipment, neutrons are emitted from a neutron source located beneath the material conveyor belt. These neutrons interact with the material being transported by the conveyor belt, generating gamma rays (γ rays). A scintillator detector plots spectral lines based on the received signals, and the energy peaks in these spectral lines are used to determine the types and composition of elements contained in the material. Summary of the Invention
[0005] Research has found that among some related technologies in material analysis equipment, the utilization rate of neutrons emitted by neutron sources is low, which not only affects the analysis efficiency but also leads to a waste of energy and operating costs.
[0006] In view of this, embodiments of the present disclosure provide a material composition analysis system that can improve the utilization rate of neutrons emitted by a neutron source.
[0007] In one aspect of this disclosure, a material composition analysis system is provided, comprising:
[0008] The neutron source is configured to generate neutrons that act on the material being tested;
[0009] A neutron moderation structure, surrounding the neutron source, is configured to moderate the neutrons produced by the neutron source;
[0010] A material receiving cavity is configured to receive the material being inspected; and
[0011] The detector assembly is configured to capture the characteristic signals generated when the material under test is bombarded by neutrons.
[0012] Wherein, at least a portion of the neutron moderation structure is located in the material receiving cavity, such that at least a portion of the neutron moderation structure is embedded within the material being inspected.
[0013] In some embodiments, the neutron moderation structure includes:
[0014] The first moderation structure includes inelastic moderation materials; and
[0015] The second moderating structure includes a first elastic moderating material and is disposed around the first moderating structure;
[0016] The first moderation structure is located between the neutron source and the second moderation structure, and the second moderation structure is located in the material receiving cavity, such that the second moderation structure is at least partially embedded in the material being inspected.
[0017] In some embodiments, the neutron moderation structure further includes:
[0018] The third moderation structure includes a second elastic moderation material and is located between the detector assembly and the second moderation structure.
[0019] In some embodiments, at least one of the first elastic moderating material and the second elastic moderating material is an elastic moderating material that does not contain carbon.
[0020] In some embodiments, the carbon-free elastic moderator material comprises a carbon-free lithium isotope containing hydrogen (H), deuterium (D), and a mass number of 7. 7 Li, beryllium (Be), and boron isotopes with a mass number of 11 11 An elastic moderating material consisting of at least one of B and oxygen (O).
[0021] In some embodiments, the carbon-free elastic moderating material includes at least one of water (H2O), heavy water (D2O), and dry water.
[0022] In some embodiments, at least one of the second and third moderating structures includes a container configured to contain and seal the carbon-free elastic moderating material, the thermal neutron capture cross section of the container material not exceeding 0.3b.
[0023] In some embodiments, the container is made of at least one of magnesium (Mg), zirconium (Zr), aluminum (Al), and aluminum oxide (Al2O3).
[0024] In some embodiments, the detector assembly includes:
[0025] A first detector is located in the material receiving cavity so that the first detector is embedded in the material being inspected.
[0026] In some embodiments, the material receiving cavity is configured to form a flow channel for the material being inspected, and the detector assembly includes two sets of first detectors located on either side of the neutron source along a first direction parallel to the extension direction of the flow channel.
[0027] In some embodiments, the portion of the first detector that comes into contact with the material being inspected has a wear-resistant structure.
[0028] In some embodiments, the material receiving cavity is configured to form a flow channel for the material being inspected, and the third slowing structure at least partially covers the inner wall of the material receiving cavity. The detector assembly includes:
[0029] The second detector is located along the second direction on the side of the third moderation structure away from the neutron source.
[0030] The second direction intersects with the extension direction of the flow channel.
[0031] In some embodiments, the detector assembly includes two sets of second detectors located on either side of the neutron source along the second direction.
[0032] In some embodiments, the detector assembly further includes:
[0033] A first detector is located in the material receiving cavity so that the first detector is embedded in the material being inspected;
[0034] The third moderation structure also has a portion located between the first detector and the second moderation structure.
[0035] In some embodiments, the material composition analysis system further includes:
[0036] A neutron-absorbing structure, located between the detector assembly and the third moderation structure, is used to absorb neutrons.
[0037] In some embodiments, the scintillator material of the detector assembly includes at least one of sodium iodide (NaI) and bismuth germanate (BGO).
[0038] In some embodiments, the material composition analysis system further includes:
[0039] Shielding materials used for radiation shielding;
[0040] The neutron source, the neutron moderation structure, and the detector assembly are located within the shielding material.
[0041] In some embodiments, the portion of the neutron moderation structure that contacts the material being tested is provided with a wear-resistant structure.
[0042] According to an embodiment of this disclosure, at least a portion of the neutron moderation structure is disposed in a material receiving cavity containing the material to be inspected, such that at least a portion of the neutron moderation structure is embedded within the material to be inspected. This allows neutrons emitted by a neutron source surrounded by the neutron moderation structure to act more on the material to be inspected after being moderated by the neutron moderation structure, thereby improving the neutron utilization rate emitted by the neutron source. Attached Figure Description
[0043] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.
[0044] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:
[0045] Figure 1 is a schematic diagram of the structure of some embodiments of the material composition analysis system according to the present disclosure;
[0046] Figure 2 is a schematic diagram of the carbon C correlation peaks in the background γ spectrum obtained according to some embodiments of the material composition analysis system of this disclosure;
[0047] Figure 3 is a schematic diagram of the structural principle of the second or third slowing structure in some embodiments of the material composition analysis system of this disclosure;
[0048] Figure 4 is a schematic diagram of the structure of some other embodiments of the material composition analysis system according to the present disclosure;
[0049] Figure 5 is a structural schematic diagram of some further embodiments of the material composition analysis system according to the present disclosure.
[0050] It should be understood that the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Furthermore, the same or similar reference numerals denote the same or similar components. Detailed Implementation
[0051] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the present disclosure or its application or use. The present disclosure may be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that the present disclosure will be thorough and complete, and will fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values set forth in these embodiments should be interpreted as exemplary only and not as limiting.
[0052] The terms "first," "second," and similar words used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. Words such as "including" or "contains" mean that the element preceding the word encompasses the element listed after it, and do not exclude the possibility of encompassing other elements as well. Terms such as "above," "below," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, this relative positional relationship may also change accordingly.
[0053] In this disclosure, when a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other devices without an intermediary device, or it may be not directly connected to the other devices but have an intermediary device.
[0054] All terms used in this disclosure (including technical or scientific terms) have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as a dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.
[0055] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.
[0056] In some related technologies of material analysis equipment, neutrons are emitted from a neutron source located beneath the material conveyor belt. These neutrons interact with the material being transported by the conveyor belt, generating gamma rays (γ rays). A scintillator detector plots spectral lines based on the received signals, and the energy peaks in these spectral lines are used to determine the types and composition of elements contained in the material.
[0057] Research has shown that the neutron source and moderation structure in this type of material composition analysis equipment are typically positioned outside the material being analyzed. Due to factors such as relative position, some neutrons emitted by the neutron source successfully reach the material and interact with the atomic nuclei to excite high-energy rays. However, some neutrons fail to reach the material due to factors such as the relative position of the neutron source and moderation structure, or they lose sufficient energy during propagation due to excessive energy attenuation, preventing them from effectively reacting with the material. This results in low neutron utilization, affecting analytical efficiency and leading to a waste of energy and operating costs.
[0058] In view of this, embodiments of the present disclosure provide a material composition analysis system that can improve the utilization rate of neutrons emitted by a neutron source.
[0059] Figure 1 is a schematic diagram of the structure of some embodiments of the material composition analysis system according to the present disclosure. Referring to Figure 1, an embodiment of the present disclosure provides a material composition analysis system, including: a neutron source 10, a neutron moderation structure 20, a material containment cavity 30, and a detector assembly 40.
[0060] Material composition analysis systems can be used for offline or online detection of tested materials (IM) to analyze their material composition. One such system is the Prompt Gamma Neutron Activation Analysis (PGNAA) system.
[0061] Neutron source 10 is configured to generate neutrons that act on the tested material IM. Neutron source 10 can generate a neutron beam through nuclear reactions such as nuclear fusion or nuclear fission, or by bombarding a target with high-energy particles. Neutron source 10 may include a radioactive neutron source, such as an (α,n) neutron source, a (γ,n) neutron source, californium-252, etc., or may include an accelerator neutron source, etc.
[0062] Neutron moderation structure 20 surrounds neutron source 10 and is configured to moderate the neutrons produced by neutron source 10. Referring to Figure 1, neutron moderation structure 20 completely surrounds neutron source 10, thus enabling the moderation of all neutrons produced by neutron source 10. Neutron moderation structure 20 can reduce neutron energy and slow down neutrons by using an elastic moderation material that achieves elastic scattering and / or an inelastic moderation material that achieves inelastic scattering, in order to obtain the desired number and energy of neutrons that can act on the inspected material IM.
[0063] The material receiving cavity 30 is configured to receive the material to be tested IM. During the testing process, the material to be tested IM can be stationary within the material receiving cavity 30 or can move within the material receiving cavity 30, for example, allowing liquid, powder, or granular materials to flow within the material receiving cavity 30 to achieve continuous material testing.
[0064] At least a portion of the neutron moderation structure 20 is located within the material receiving cavity 30, such that at least a portion of the neutron moderation structure 20 is embedded within the material under test IM. Preferably, the entire neutron moderation structure 20 is located within the material receiving cavity 30. Since the material under test IM occupies a certain volume within the material receiving cavity 30, the partial or complete embedding of the neutron moderation structure 20 within the material under test IM allows for greater application of moderated neutrons to the material under test IM.
[0065] Detector assembly 40 is configured to capture characteristic signals generated after the tested material IM is bombarded by neutrons. For example, detector assembly 40 can capture gamma-ray signals generated after the tested material IM is bombarded by neutrons, or it can capture other signals such as neutrons. In some embodiments, detector assembly 40 can also perform signal conversion and processing on the captured characteristic signals.
[0066] In this embodiment, at least a portion of the neutron moderation structure 20 is disposed in the material receiving cavity 30 containing the material under test IM, such that at least a portion of the neutron moderation structure 20 is embedded within the material under test IM. This allows the neutrons emitted by the neutron source 10 surrounded by the neutron moderation structure 20 to act more on the material under test IM after being moderated by the neutron moderation structure 20, thereby improving the utilization rate of the neutrons emitted by the neutron source 10.
[0067] Referring to Figure 1, in some embodiments, a wear-resistant structure 70 is provided at the part of the neutron moderating structure 20 that contacts the tested material IM. The wear-resistant structure 70 minimizes wear on the neutron moderating structure 20 when it is in contact with or in contact with the tested material IM, thereby improving the reliability and service life of the neutron moderating structure 20. The wear-resistant structure 70 can take the form of a wear-resistant coating or a wear-resistant shell. In terms of materials, materials with high hardness and limited impact on the analytical accuracy of the material composition analysis system can be used, such as alumina (Al2O3) ceramics.
[0068] Referring to Figure 1, in some embodiments, the neutron moderation structure 20 includes a first moderation structure 21 and a second moderation structure 22. The first moderation structure 21 includes an inelastic moderator material. The inelastic moderator material can reduce neutron energy through inelastic scattering of neutrons; for example, the inelastic moderator material may include a bismuth-containing Bi material.
[0069] The second moderation structure 22 includes a first elastic moderation material and is disposed around the first moderation structure 21. The first moderation structure 21 is located between the neutron source 10 and the second moderation structure 22, and the second moderation structure 22 is located in the material receiving cavity 30 such that at least a portion of the second moderation structure 22 is embedded within the material under test IM.
[0070] The first moderation structure 21 is positioned between the neutron source 10 and the second moderation structure 22. It can quickly reduce the energy of the high-energy neutrons emitted by the neutron source 10 and reduce the number of neutrons reaching the second moderation structure 22 by absorbing some of the neutrons. This helps to reduce the requirements of the second moderation structure 22 on factors such as materials and distances required for neutron moderation.
[0071] The second moderating structure 22 includes a first elastic moderating material that can reduce neutron energy through elastic scattering of neutrons, such as materials containing graphite, polyethylene (PE), paraffin, water, heavy water, etc. The second moderating structure 22 can be disposed within the material receiving cavity 30, and part or all of it can be embedded within the material being inspected IM.
[0072] In Figure 1, the second moderating structure 22 can be entirely enclosed outside the first moderating structure 22, while the first moderating structure 21 can be entirely enclosed outside the neutron source 10. Referring to the vertically arranged centerline in Figure 1, the second moderating structure 22 can be designed as a cylinder with a cylindrical inner cavity, while the first moderating structure 21 is located inside the cylindrical inner cavity and is also cylindrical. A through-hole along the axis can be provided on the first moderating structure 21 and the second moderating structure 22, and the neutron source 10 is located inside the hole.
[0073] Referring to FIG1, in some embodiments, the neutron moderation structure 20 further includes a third moderation structure 23, which includes a second elastic moderation material and is located between the detector assembly 40 and the second moderation structure 22.
[0074] The third moderating structure 23 includes a second elastic moderating material that can reduce neutron energy through elastic scattering of neutrons. Examples of materials include graphite, polyethylene (PE), paraffin, water, and heavy water. The third moderating structure 23 is positioned between the detector assembly 40 and the second moderating structure 22. This allows neutrons modulated by the second moderating structure 22 to not directly enter the detector assembly 40, but instead act on the surrounding sample material IM or be further slowed and absorbed by the third moderating structure 22. This allows for more precise control of neutron energy, reduces interference from neutrons directly entering the detector assembly 40 on the characteristic signal, and reduces the risk of neutron leakage into the external environment by absorbing excess neutrons. Referring to Figure 1, for example, if the second moderating structure 22 is designed as a cylinder, the third moderating structure 23 can be designed as two cylinders of the same diameter, coaxially positioned at both ends of the second moderating structure 22.
[0075] According to the theory of elastic moderation of neutrons, the selection of moderation materials for the first and second elastic moderation materials can be based on two indicators: the moderation capacity and the moderation ratio. The goal is to achieve both a high moderation capacity to reduce the amount of material used and a high moderation ratio to minimize neutron loss.
[0076] Based on the goal of maximizing thermal neutron flux, it is possible to obtain neutrons from sources containing deuterium (D), oxygen (O), beryllium (Be), and boron isotopes with a mass number of 11. 11 B, carbon C, containing lithium isotopes with a mass number of 7 7 Moderators are selected from materials containing Li and hydrogen (H).
[0077] In some embodiments, at least one of the first elastic moderating material and the second elastic moderating material may be a carbon-containing material, such as graphite, paraffin, polyethylene, etc. Such materials have excellent mechanical properties and a moderating ratio second only to deuterium D and oxygen O.
[0078] For some embodiments of detector assembly 40 that include scintillator detectors, for example, the scintillator material of detector assembly 40 includes at least one of sodium iodide (NaI) and bismuth germanate (BGO). Using a C-rich material near the neutron source 10 and the detector may result in significant C-based neutron-captured gamma peaks, neutron inelastic gamma peaks, neutron-captured gamma single escape peaks, neutron inelastic gamma single escape peaks, and neutron-captured gamma double escape peaks appearing in the background gamma spectrum (i.e., when there is no material to be tested) measured by the material composition analysis system. This may affect the measurement accuracy of some elements to be analyzed that depend on the positions of these energy peaks.
[0079] Figure 2 is a schematic diagram of the carbon C-related peaks in the background gamma spectrum obtained according to some embodiments of the material composition analysis system of this disclosure. As can be seen from Figure 2, when a large amount of C-containing material is used as the moderator, three peaks at 4.945 MeV, 4.44 MeV, and 3.93 MeV are introduced. Studies have shown that for devices using crystals such as NaI or BGO as detector materials, this will affect the measurement accuracy of the analyte elements that depend on the positions of these three energy peaks. These analytes include, for example, neon (Ne, gamma peak energy 4.374 MeV), magnesium (Mg, gamma peak energy 3.917 MeV), phosphorus (P, gamma peak energy 3.900 MeV), barium (Ba, gamma peak energy 4.096 MeV), lanthanum (La, gamma peak energies 4.847 MeV and 5.098 MeV), cerium (Ce, gamma peak energy 4.766 MeV), and uranium (U, gamma peak energy 4.060 MeV).
[0080] Based on the above research, in some embodiments of this disclosure, at least one of the first elastic moderating material and the second elastic moderating material is an elastic moderating material that does not contain carbon. Specifically, the first elastic moderating material can be an elastic moderating material that does not contain carbon, the second elastic moderating material can be an elastic moderating material that does not contain carbon, or both the first and second elastic moderating materials can be elastic moderating materials that do not contain carbon.
[0081] This effectively reduces the count rate of carbon (C) related peaks, thereby improving the analytical accuracy of elements such as neon (Ne), magnesium (Mg), phosphorus (P), barium (Ba), lanthanum (La), cerium (Ce), and uranium (U). This allows companies in industries such as mining, batching, and smelting to further improve their economic efficiency.
[0082] In some embodiments, the carbon-free elastic moderator material may be selected as a carbon-free material containing hydrogen (H), deuterium (D), and a lithium isotope with a mass number of 7. 7 Li, beryllium (Be), and boron isotopes with a mass number of 11 11 An elastic moderating material consisting of at least one of B and oxygen (O).
[0083] Among these elastic moderators, hydrogen (H) has the highest elastic scattering cross section, and materials containing hydrogen (H) but without carbon (C) exhibit the strongest moderation ability. Ranked by moderation ratio, the most preferred material is one containing deuterium (D) but without carbon (C), followed by materials containing oxygen (O), beryllium (Be), and boron isotopes with a mass number of 11. 11 B. Lithium isotopes with a mass number of 7 7 Materials containing Li and hydrogen (H).
[0084] From an economic perspective, choosing a material that contains no carbon (C) and contains hydrogen (H) is the most economical option. From a machinability standpoint, beryllium (Be) offers the best machinability.
[0085] Select lithium isotopes with a mass number of 7. 7 When Li materials are used as moderators, the lithium isotope with a mass number of 6 is taken into account. 6 Li undergoes an (n,t) reaction and strongly absorbs thermal neutrons; therefore, this material contains neither carbon (C) nor lithium isotopes with a mass number of 6. 6 Li.
[0086] Select a boron isotope with a mass number of 11. 11 When material B is used as a moderator, boron isotopes with a mass number of 10 are taken into account. 10 B undergoes an (n,α) reaction and strongly absorbs thermal neutrons; therefore, this material contains neither carbon (C) nor any boron isotope with a mass number of 10. 10 B.
[0087] Based on the above research and analysis, in some embodiments, the carbon-free elastic moderating material includes at least one of water (H2O), heavy water (D2O), and dry water. Dry water is a special powdery material formed by tiny water droplets encapsulated in hydrophobic silica nanoparticles (although it looks like a dry powder, it actually contains about 95% water, hence the name "dry water").
[0088] Compared to boron isotopes that require isotope separation 11 B and lithium isotopes 7 Li, more expensive beryllium (Be), and toxic Be compounds, at least one of water (H2O), heavy water (D2O), and dry water has better safety, economy, and slowing effect.
[0089] Figure 3 is a schematic diagram of the structural principle of the second or third moderating structure according to some embodiments of the material composition analysis system of this disclosure. Referring to Figure 3, for embodiments in which at least one of the first and second elastic moderating materials is water (H2O), heavy water (D2O), and dry water as the elastic moderating material, in order to keep such fluid or fluid-like material in the corresponding position, in some embodiments, at least one of the second moderating structure 22 and the third moderating structure 23 includes a container 20b, which is configured to contain and seal the carbon-free elastic moderating material 20a, and the thermal neutron capture cross section of the material of the container 20b does not exceed 0.3b.
[0090] Container 20b can retain fluids or fluid-like elastic moderating materials such as water (H2O), heavy water (D2O), or dry water, and its thermal neutron trapping cross section does not exceed 0.3b, which can reduce the probability of neutron trapping in container 20b and thus reduce neutron loss. When the required measurement accuracy can be guaranteed, a carbon-containing material can be appropriately selected as the material for container 20b.
[0091] In some embodiments, the container material includes at least one of magnesium (Mg), zirconium (Zr), aluminum (Al), and aluminum oxide (Al₂O₃). These materials are carbon-free (C), which reduces the influence of C's energy peak on some other analyte elements, and also have high material strength.
[0092] Referring to Figure 1, in some embodiments, the material composition analysis system further includes a neutron absorption structure 50 located between the detector assembly 40 and the third moderation structure 23 for absorbing neutrons. For the detector assembly 40 performing composition analysis via gamma spectroscopy, the neutron absorption structure 50 can reduce the number of neutrons reaching the detector assembly 40 by absorbing neutrons, thereby reducing the impact on the analysis results of the material composition analysis system.
[0093] Neutron absorption structure 50 can be made using a lithium isotope with a mass number of 6. 6 The material Li can effectively absorb thermal neutrons and emit virtually no gamma rays, thereby reducing both the interference of neutrons on the detector assembly 40 and the interference of gamma rays not generated by the interaction between the tested material IM and neutrons.
[0094] Referring to Figure 1, in some embodiments, the material composition analysis system further includes a shielding material 60. The shielding material 60 is used for radiation shielding, and the neutron source 10, the neutron moderation structure 20, and the detector assembly 40 are located within the shielding material 60.
[0095] Shielding material 60 can be used to shield neutrons, gamma rays, or other radiation from the material composition analysis system to the external environment, preventing pollution. Shielding material 60 can be made of lead (Pb), tungsten (W), concrete, boron-containing polyethylene, etc.
[0096] In the above embodiments, by embedding at least a portion of the neutron source 10 and the neutron moderation structure 20 in the material to be tested IM, the utilization rate of neutrons emitted by the neutron source 10 can be effectively improved, and the structure of the material composition analysis system can be made compact, reducing space occupation.
[0097] Based on this, referring to FIG1, in some embodiments, the detector assembly 40 includes a first detector 41. The first detector 41 is located in the material receiving cavity 30 so that the first detector 41 is embedded in the material to be inspected IM.
[0098] In Figure 1, the neutron source 10, the neutron moderation structure 20, and the first detector 41 are all embedded within the material being tested, IM. This structure allows for a more compact material composition analysis system, significantly reducing space requirements.
[0099] Referring to FIG1, in some embodiments, the material receiving cavity 30 is configured to form a flow channel for the material to be inspected IM, and the detector assembly 40 includes two sets of first detectors 41 located on both sides of the neutron source 10 along a first direction dr1, the first direction dr1 being parallel to the extension direction of the flow channel.
[0100] In Figure 1, the material under test, IM, can flow along the vertically drawn axis of the material receiving cavity 30, allowing the material composition analysis system to perform material composition analysis on the continuously flowing material IM at different time ranges. Two sets of first detectors 41 are positioned on both sides of the neutron source 10 along the first direction dr1, each set including one or more first detectors 41. The two sets of first detectors 41 can capture characteristic signals along the first direction dr1 at the front and rear sides of the neutron source 10, thereby increasing the probability of detecting the characteristic signals.
[0101] Referring to Figure 1, in some embodiments, the portion of the first detector 41 that contacts the material IM being tested is provided with a wear-resistant structure 70. The wear-resistant structure 70 minimizes wear on the first detector 41 when it is in contact with or in contact with the material IM being tested, thereby improving the reliability and service life of the first detector 41. The wear-resistant structure 70 can take the form of a wear-resistant coating or a wear-resistant shell. In terms of materials, materials with high hardness and limited impact on the analytical accuracy of the material composition analysis system can be used, such as alumina (Al2O3) ceramics.
[0102] Figure 4 is a schematic diagram of the structure of some other embodiments of the material composition analysis system according to the present disclosure. Referring to Figure 4, in some embodiments, the material receiving cavity 30 is configured to form a flow channel for the tested material IM, and at least a portion of the third moderating structure 23 covers the inner wall of the material receiving cavity 30, preferably, the third moderating structure 23 covers the entire inner wall of the material receiving cavity 30. The detector assembly 40 includes a second detector 42 located along a second direction dr2 on the side of the third moderating structure 23 away from the neutron source 10. The second direction dr2 intersects the extension direction of the flow channel.
[0103] In Figure 4, the third moderating structure 23 may include a tubular portion covering the inner wall of the material receiving cavity 30 to form a tubular flow channel with the second moderating structure 22 and the shielding material 60. The third moderating structure 23 can moderate neutrons and absorb excess neutrons.
[0104] In Figure 4, the material under test, IM, can flow within the material receiving cavity 30 along the vertically drawn axis, allowing the material composition analysis system to perform material composition analysis on the continuously flowing material under test, IM, at different time intervals. The second detector 42 is located on the side of the third moderation structure 23 away from the neutron source 10 along the second direction dr2. Here, the second direction dr2 can intersect with the extension direction of the flow channel, for example, perpendicular to the first direction dr1 or at an acute or obtuse angle.
[0105] Referring to Figure 4, in some embodiments, the detector assembly 40 includes two sets of second detectors 42, which are located on both sides of the neutron source 10 along a second direction dr2. There may be more than one second direction dr2; that is, the two sets of second detectors 42 may be located on both sides of the neutron source 10 along one or more second directions dr2 intersecting the first direction dr1.
[0106] Each of the two sets of second detectors 42 may include one or more second detectors 42. The two sets of second detectors 42 can capture characteristic signals along the second direction dr2 on the front and rear sides of the neutron source 10 to improve the probability of detecting the characteristic signals. The two sets of second detectors 42 may be symmetrical or offset relative to the vertically drawn center line in Figure 4.
[0107] In this embodiment, multiple second detectors 42 can be arranged in the third slowing structure 23 as needed, so that these detectors are distributed around the material being measured IM. This can effectively increase the probability of detecting characteristic signals and improve measurement accuracy. Moreover, this arrangement is beneficial for the compositional analysis of the material being measured IM in fluid or fluid-like forms.
[0108] Figure 5 is a schematic structural diagram of some further embodiments of the material composition analysis system according to the present disclosure. Referring to Figure 5, compared with the embodiment shown in Figure 4, in some embodiments, the detector assembly 40 further includes a first detector 41 located in the material receiving cavity 30 such that the first detector 41 is embedded in the material IM to be tested. The third moderating structure 23 also has a portion located between the first detector 41 and the second moderating structure 22.
[0109] In this embodiment, the first detector 41 and the second detector 42 are positioned outside the neutron source 10 and the neutron moderation structure 20 along the first direction dr1 and the second direction dr2. This achieves a compact structure while further increasing the probability of detecting characteristic signals, thereby achieving higher analysis accuracy.
[0110] In the above embodiments, the respective detectors included in the detector assembly 40 can be housed in a container containing heat-insulating material to prevent the detectors from failing or being damaged due to excessive temperature, thereby improving the reliability of the detector assembly 40.
[0111] Taking a scenario where the tested material IM is magnesium ore (Mg), and the material composition analysis system is used to analyze the Mg content in the Mg ore, as an example, the particle size of the tested Mg ore is 50 mm. The arrangement structure shown in Figure 4 is adopted. The first elastic moderating material of the second moderating structure 22 and the second elastic moderating material of the third moderating structure 23 both use H2O. The inelastic moderating material of the first moderating structure 21 uses bismuth (Bi). The neutron absorption structure 50 uses a lithium isotope with a mass number of 6. 6 The material is Li. The thickness of the first moderation structure 21 is 2–3 cm, the thickness of the second moderation structure 22 is 2–3 cm, the thickness of the third moderation structure is 8–10 cm, and the thickness of the neutron absorption structure 50 is 3–4 cm. Testing showed that the analytical precision of the Mg composition could be improved from 0.45% to 0.30%.
[0112] Taking another tested material, IM, as an example, a material composition analysis system is used to analyze the phosphorus content in this phosphorus ore. The particle size of the tested phosphorus ore is 1 mm, and the arrangement structure shown in Figure 5 is adopted. The first elastic moderating material of the second moderating structure 22 and the second elastic moderating material of the third moderating structure 23 are both H2O. The inelastic moderating material of the first moderating structure 21 is bismuth (Bi). The neutron absorption structure 50 uses a lithium isotope with a mass number of 6. 6 The material is Li. The thickness of the first moderation structure 21 is 2–3 cm, the thickness of the second moderation structure 22 is 2–3 cm, the thickness of the third moderation structure is 8–10 cm, and the thickness of the neutron absorption structure 50 is 3–4 cm. Testing showed that the analytical precision of the P component improved from 0.90% to 0.60%.
[0113] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.
[0114] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.
Claims
1. A material composition analysis system, comprising: A neutron source (10) is configured to generate neutrons that act on the material under test (IM); A neutron moderation structure (20) surrounds the neutron source (10) and is configured to moderate the neutrons produced by the neutron source (10); The material receiving cavity (30) is configured to receive the material to be inspected (IM); and The detector assembly (40) is configured to capture the characteristic signal generated by the test material (IM) after being bombarded by neutrons; At least a portion of the neutron moderation structure (20) is located in the material receiving cavity (30) so that at least a portion of the neutron moderation structure (20) is embedded in the material under test (IM).
2. The material composition analysis system according to claim 1, wherein, The neutron moderation structure (20) includes: The first moderating structure (21) includes an inelastic moderating material; and The second moderating structure (22) includes a first elastic moderating material and is disposed around the first moderating structure (21); The first moderation structure (21) is located between the neutron source (10) and the second moderation structure (22), and the second moderation structure (22) is located in the material receiving cavity (30) so that the second moderation structure (22) is at least partially embedded in the material under test (IM).
3. The material composition analysis system according to claim 2, wherein, The neutron moderation structure (20) also includes: The third moderation structure (23) includes a second elastic moderation material and is located between the detector assembly (40) and the second moderation structure (22).
4. The material composition analysis system according to claim 3, wherein, At least one of the first elastic moderating material and the second elastic moderating material is an elastic moderating material that does not contain carbon.
5. The material composition analysis system according to claim 4, wherein, The carbon-free elastic moderator material includes carbon-free materials containing hydrogen (H), deuterium (D), and a lithium isotope with a mass number of 7. 7 Li, beryllium (Be), and boron isotopes with a mass number of 11 11 An elastic moderating material consisting of at least one of B and oxygen (O).
6. The material composition analysis system according to claim 5, wherein, The carbon-free elastic moderating material includes at least one of water (H2O), heavy water (D2O), and dry water.
7. The material composition analysis system according to any one of claims 4-6, wherein, At least one of the second moderation structure (22) and the third moderation structure (23) includes a container configured to contain and seal the carbon-free elastic moderation material, wherein the thermal neutron capture cross section of the material of the container does not exceed 0.3b.
8. The material composition analysis system according to claim 7, wherein, The container is made of at least one of magnesium (Mg), zirconium (Zr), aluminum (Al), and aluminum oxide (Al2O3).
9. The material composition analysis system according to any one of claims 1-8, wherein, The detector assembly (40) includes: A first detector (41) is located in the material receiving cavity (30) so that the first detector (41) is embedded in the material to be inspected (IM).
10. The material composition analysis system according to claim 9, wherein, The material receiving cavity (30) is configured to form a flow channel for the material under test (IM), and the detector assembly (40) includes two sets of first detectors (41) located on both sides of the neutron source (10) along a first direction (dr1) parallel to the extension direction of the flow channel.
11. The material composition analysis system according to claim 9 or 10, wherein, The part of the first detector (41) that comes into contact with the material being inspected (IM) is provided with a wear-resistant structure (70).
12. The material composition analysis system according to any one of claims 3-8, wherein, The material receiving cavity (30) is configured to form a flow channel for the inspected material (IM), at least a portion of the third slowing structure (23) covers the inner wall of the material receiving cavity (30), and the detector assembly (40) includes: The second detector (42) is located along the second direction (dr2) on the side of the third moderation structure (23) away from the neutron source (10). The second direction (dr2) intersects with the extension direction of the flow channel.
13. The material composition analysis system according to claim 12, wherein, The detector assembly (40) includes two sets of second detectors (42) located on both sides of the neutron source (10) along the second direction (dr2).
14. The material composition analysis system according to claim 12 or 13, wherein, The detector assembly (40) also includes: A first detector (41) is located in the material receiving cavity (30) so that the first detector (41) is embedded in the material to be inspected (IM); The third slowing structure (23) also has a portion located between the first detector (41) and the second slowing structure (22).
15. The material composition analysis system according to any one of claims 3-8 and 12-14, further comprising: A neutron-absorbing structure (50), located between the detector assembly (40) and the third moderation structure (23), is used to absorb neutrons.
16. The material composition analysis system according to any one of claims 1-15, wherein, The scintillator material of the detector assembly (40) includes at least one of sodium iodide (NaI) and bismuth germanate (BGO).
17. The material composition analysis system according to any one of claims 1-16, further comprising: Shielding material (60), used for radiation shielding; The neutron source (10), the neutron moderation structure (20), and the detector assembly (40) are located within the shielding material (60).
18. The material composition analysis system according to any one of claims 1-17, wherein, The part of the neutron moderation structure (20) that comes into contact with the material under test (IM) is provided with a wear-resistant structure (70).