Substance component analysis system

Abstract

A substance composition analysis system includes: a neutron source (10) configured to generate neutrons acting on a material (IM) to be inspected; the neutron moderation structure (20) surrounds the neutron source (10) and is configured to moderate neutrons generated by the neutron source (10); the material accommodating cavity (30) is configured to accommodate the detected material (IM); the detector assembly (40) is configured to capture a characteristic signal generated after the detected material (IM) is bombarded by neutrons; wherein at least part of the neutron moderation structure (20) is located in the material containing cavity (30), so that at least part of the neutron moderation structure (20) is buried in the detected material (IM). The utilization rate of neutrons emitted by the neutron source can be improved.

Description

Technical Field

[0001] The present disclosure relates to material analysis technology, and in particular to a material composition analysis system. Background Art

[0002] In some related technologies of material analysis equipment, neutrons are emitted by a neutron source on the lower side of the material conveyor belt so as to generate gamma rays (γ rays) by using the neutrons to interact with the material conveyed by the material conveyor belt. The scintillator detector draws a spectrum based on the signal it receives so as to determine the type and composition of elements contained in the material based on the energy peaks in the spectrum. Summary of the invention

[0003] Research has found that in some related technologies of material analysis equipment, the utilization rate of neutrons emitted by the neutron source is low, which not only affects the analysis efficiency, but also leads to waste of energy and operating costs.

[0004] In view of this, an embodiment of the present disclosure provides a material composition analysis system that can improve the utilization rate of neutrons emitted by a neutron source.

[0005] In one aspect of the present disclosure, there is provided a material composition analysis system, comprising: a neutron source configured to generate neutrons for acting on a material to be inspected; a neutron moderating structure, surrounding the neutron source and configured to moderate neutrons generated by the neutron source; a material containing chamber, configured to contain the inspected material; and A detector assembly configured to capture characteristic signals generated by the inspected material after being bombarded by neutrons; Wherein, at least a portion of the neutron moderating structure is located in the material containing cavity, so that at least a portion of the neutron moderating structure is buried in the inspected material.

[0006] In some embodiments, the neutron moderating structure comprises: A first moderator structure comprising an inelastic moderator material; and A second moderator structure includes a first elastic moderator material and is disposed around the first moderator structure; The first moderator structure is located between the neutron source and the second moderator structure, and the second moderator structure is located in the material containing cavity, so that the second moderator structure is at least partially buried in the inspected material.

[0007] In some embodiments, the neutron moderating structure further comprises: The third moderator structure includes a second elastic moderator material and is located between the detector assembly and the second moderator structure.

[0008] In some embodiments, at least one of the first elastic moderator material and the second elastic moderator material is an elastic moderator material that does not contain carbon elements.

[0009] In some embodiments, the elastic moderator material containing no carbon element includes no carbon and contains hydrogen H, deuterium D, and lithium isotope with a mass number of 7. 7 Li, beryllium Be, boron isotope with mass number 11 11 An elastic moderating material of at least one of B and oxygen O.

[0010] In some embodiments, the elastic moderator material not containing carbon elements includes at least one of water H2O, heavy water D2O and dry water.

[0011] In some embodiments, at least one of the second moderator structure and the third moderator structure comprises a container configured to contain and seal the elastic moderator material that does not contain carbon elements, and the thermal neutron capture cross section of the material of the container does not exceed 0.3b.

[0012] In some embodiments, the material of the container includes at least one of magnesium Mg, zirconium Zr, aluminum Al, and aluminum oxide Al2O3.

[0013] In some embodiments, the detector assembly comprises: The first detector is located in the material containing cavity so that the first detector is buried in the inspected material.

[0014] In some embodiments, the material holding chamber is configured to form a flow channel for the inspected material, and the detector assembly includes two groups of first detectors, which are located on both sides of the neutron source along a first direction, and the first direction is parallel to the extension direction of the flow channel.

[0015] In some embodiments, a wear-resistant structure is provided at a portion of the first detector that contacts the inspected material.

[0016] In some embodiments, the material holding cavity is configured to form a flow channel for the inspected material, at least a portion of the third moderation structure is coated on an inner wall of the material holding cavity, and the detector assembly includes: a second detector, located along the second direction on a side of the third moderator structure away from the neutron source, Wherein, the second direction intersects with an extending direction of the flow channel.

[0017] In some embodiments, the detector assembly includes two groups of second detectors, and the two groups of second detectors are located on both sides of the neutron source along the second direction.

[0018] In some embodiments, the detector assembly further comprises: A first detector is located in the material containing cavity so that the first detector is buried in the inspected material; The third moderation structure further has a portion located between the first detector and the second moderation structure.

[0019] In some embodiments, the material composition analysis system further includes: The neutron absorption structure is located between the detector assembly and the third moderator structure and is used for absorbing neutrons.

[0020] In some embodiments, the scintillator material of the detector assembly includes at least one of sodium iodide NaI and bismuth germanate BGO.

[0021] In some embodiments, the material composition analysis system further includes: Shielding materials, used for radiation shielding; Wherein, the neutron source, the neutron moderating structure and the detector assembly are located inside the shielding material.

[0022] In some embodiments, a wear-resistant structure is provided at a portion where the neutron moderating structure contacts the inspected material.

[0023] According to an embodiment of the present disclosure, at least a portion of the neutron moderating structure is disposed in a material containing cavity that contains the material to be inspected, so that at least a portion of the neutron moderating structure is buried in the material to be inspected. This allows the neutrons emitted by the neutron source surrounded by the neutron moderating structure to act more on the material to be inspected after being slowed down by the neutron moderating structure, thereby improving the utilization rate of the neutrons emitted by the neutron source. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0025] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which: Figure 1 is a schematic diagram of the structure of some embodiments of the material composition analysis system according to the present disclosure; Figure 2 is a schematic diagram of carbon C related peaks in the background γ spectrum obtained according to some embodiments of the material composition analysis system disclosed in the present invention; Figure 3 is a schematic diagram of the structural principle of the second moderator structure or the third moderator structure in some embodiments of the material composition analysis system according to the present disclosure; Figure 4 is a schematic diagram of the structure of other embodiments of the material composition analysis system according to the present disclosure; Figure 5 It is a schematic diagram of the structure of some further embodiments of the material composition analysis system according to the present disclosure.

[0026] It should be understood that the size of each part shown in the accompanying drawings is not drawn according to the actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. DETAILED DESCRIPTION

[0027] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the components and steps, the composition of the materials, the numerical expressions and the numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary and not as limiting.

[0028] The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. The words "include" or "comprise" and similar words mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of including other elements. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0029] In the present disclosure, when a specific device is described as being located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other device without an intermediate device, or may not be directly connected to the other device but have an intermediate device.

[0030] All terms (including technical terms or scientific terms) used in the present disclosure have the same meanings as those understood by ordinary technicians in the field to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, such as general dictionaries, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined herein.

[0031] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0032] In some related technologies of material analysis equipment, neutrons are emitted by a neutron source on the lower side of the material conveyor belt so as to generate gamma rays (γ rays) by using the neutrons to interact with the material conveyed by the material conveyor belt. The scintillator detector draws a spectrum based on the signal it receives so as to determine the type and composition of elements contained in the material based on the energy peaks in the spectrum.

[0033] Research has found that the neutron source and moderator structure in this material composition analysis equipment are usually arranged outside the material to be inspected. Based on the influence of factors such as relative position, some neutrons emitted by the neutron source can successfully reach the material to be inspected and interact with the atomic nuclei therein to stimulate high-energy rays. However, some neutrons cannot reach the material to be inspected due to factors such as the relative position of the neutron source and moderator structure to the material to be inspected, or lose sufficient energy due to excessive energy attenuation during the propagation process, resulting in their inability to effectively react with the material. This makes the utilization rate of neutrons emitted by the neutron source low, which not only affects the analysis efficiency, but also leads to a waste of energy and operating costs.

[0034] In view of this, an embodiment of the present disclosure provides a material composition analysis system that can improve the utilization rate of neutrons emitted by a neutron source.

[0035] Figure 1 Schematic diagram of the structure of some embodiments of the material composition analysis system according to the present disclosure. Figure 1 The embodiment of the present disclosure provides a material composition analysis system, including: a neutron source 10, a neutron moderation structure 20, a material containing cavity 30 and a detector assembly 40.

[0036] The material composition analysis system can be used to perform offline or online detection on the inspected material IM to analyze the material composition of the inspected material IM. The material composition analysis system can be a prompt gamma neutron activation analysis (PGNAA) material composition analysis system.

[0037] The neutron source 10 is configured to generate neutrons that act on the inspected material IM. The neutron source 10 can generate a neutron beam by a nuclear reaction such as nuclear fusion or nuclear fission, or can generate neutrons by bombarding a target with high-energy particles. The 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 include an accelerator neutron source, etc.

[0038] The neutron moderating structure 20 surrounds the neutron source 10 and is configured to moderate the neutrons generated by the neutron source 10. Figure 1The neutron moderator structure 20 completely surrounds the neutron source 10, so that all neutrons generated by the neutron source 10 can be moderated. The neutron moderator structure 20 can reduce the neutron energy and slow down the neutrons by using an elastic moderator material that realizes elastic scattering and / or an inelastic moderator material that realizes inelastic scattering, so as to obtain neutrons of a desired number and energy that can act on the inspected material IM.

[0039] The material holding chamber 30 is configured to hold the inspected material IM. During the inspection process, the inspected material IM can be statically arranged in the material holding chamber 30, or can move in the material holding chamber 30, for example, liquid, powder or granular material can flow in the material holding chamber 30 to achieve continuous inspection of the material.

[0040] At least part of the neutron moderator structure 20 is located in the material containing chamber 30, so that at least part of the neutron moderator structure 20 is buried in the material to be inspected IM. Preferably, the entire neutron moderator structure 20 is located in the material containing chamber 30. The material to be inspected IM occupies a certain volume in the material containing chamber 30, and part or the entire neutron moderator structure 20 is buried in the material to be inspected IM, so that the moderated neutrons can act more on the material to be inspected IM.

[0041] The detector assembly 40 is configured to capture characteristic signals generated by the inspected material IM after being bombarded by neutrons. For example, the detector assembly 40 can capture gamma-ray signals generated by the inspected material IM after being bombarded by neutrons, and can also capture other signals such as neutrons. In some embodiments, the detector assembly 40 can also perform signal conversion and processing on the captured characteristic signals.

[0042] In the present embodiment, at least a portion of the neutron moderating structure 20 is disposed in a material containing cavity 30 containing the material to be inspected IM, so that at least a portion of the neutron moderating structure 20 is buried in the material to be inspected IM. This allows the neutrons emitted by the neutron source 10 surrounded by the neutron moderating structure 20 to act more on the material to be inspected IM after being slowed down by the neutron moderating structure 20, thereby improving the utilization rate of the neutrons emitted by the neutron source 10.

[0043] refer to Figure 1 In some embodiments, a wear-resistant structure 70 is provided at the part where the neutron moderator structure 20 contacts the inspected material IM. The wear-resistant structure 70 can minimize the wear of the neutron moderator structure 20 when the neutron moderator structure 20 contacts the inspected material IM or contacts and rubs against the inspected material IM, so as to improve the reliability and service life of the neutron moderator structure 20. The wear-resistant structure 70 can be in the form of a wear-resistant coating or a wear-resistant shell. In terms of material, a material with a relatively high hardness and a relatively limited impact on the analysis accuracy of the material composition analysis system can be used, such as aluminum oxide (Al2O3) ceramics.

[0044] refer to Figure 1 In some embodiments, the neutron moderator structure 20 includes: a first moderator structure 21 and a second moderator structure 22. The first moderator structure 21 includes an inelastic moderator material. The inelastic moderator material can reduce the neutron energy by inelastic scattering of neutrons. For example, the inelastic moderator material may include a bismuth-containing Bi material.

[0045] The second moderator structure 22 includes a first elastic moderator material and is disposed around the first moderator structure 21. The first moderator structure 21 is located between the neutron source 10 and the second moderator structure 22, and the second moderator structure 22 is located in the material receiving chamber 30 so that at least a portion of the second moderator structure 22 is buried in the inspected material IM.

[0046] The first moderator structure 21 is disposed between the neutron source 10 and the second moderator structure 22, and can quickly reduce the energy of high-energy neutrons emitted by the neutron source 10, and reduce the number of neutrons reaching the second moderator structure 22 by absorbing a portion of the neutrons, which is beneficial to reducing the requirements of the second moderator structure 22 for factors such as materials and distance required for neutron moderation.

[0047] The first elastic moderator material included in the second moderator structure 22 can reduce the neutron energy by elastic scattering of neutrons, such as graphite, polyethylene (PE), paraffin, water, heavy water, etc. The second moderator structure 22 can be arranged in the material containing cavity 30, and a part or the whole of the second moderator structure 22 is buried in the inspected material IM.

[0048] exist Figure 1 In the embodiment, the second moderator structure 22 can be entirely wrapped around the outside of the first moderator structure 22, and the first moderator structure 21 can be entirely wrapped around the outside of the neutron source 10. Figure 1 The second moderator structure 22 can be designed to be cylindrical and have a cylindrical inner cavity, while the first moderator structure 21 is located in the cylindrical inner cavity and is also cylindrical. A hole passing through the first moderator structure 21 and the second moderator structure 22 can be provided along the axis, and the neutron source 10 is located in the hole.

[0049] refer to Figure 1 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 .

[0050] The second elastic moderation material included in the third moderation structure 23 can reduce the neutron energy by elastic scattering of neutrons, such as materials containing graphite, polyethylene (PE), paraffin, water, heavy water, etc. The third moderation structure 23 is arranged between the detector assembly 40 and the second moderation structure 22, so that the neutrons slowed down by the second moderation structure 22 do not directly enter the detector assembly 40, but act on the surrounding inspected material IM or are further slowed down and absorbed by the third moderation structure 22, so as to more finely control the neutron energy, reduce the interference of neutrons directly entering the detector assembly 40 on the characteristic signal, and reduce the risk of neutron leakage to the external environment by absorbing excess neutrons. Reference Figure 1 For example, when the second moderator structure 22 can be designed as a cylindrical shape, the third moderator structure 23 can be designed as two cylindrical shapes with the same diameter, and are coaxially arranged at both ends of the second moderator structure 22 respectively.

[0051] According to the elastic slowing-down theory of neutrons, for the first elastic slowing-down material and the second elastic slowing-down material, the selection of slowing-down materials can examine two indicators: the slowing-down ability and the slowing-down ratio of the material. Both high slowing-down ability is pursued to use less material, and high slowing-down ratio is pursued to reduce neutron loss.

[0052] Based on the goal of maximizing the thermal neutron flux, the neutron flux can be obtained from deuterium D, oxygen O, beryllium Be, and boron isotopes with mass number 11. 11 B, carbon C, lithium isotope with mass number 7 7 The moderating material is selected from the materials of Li and hydrogen H.

[0053] In some embodiments, at least one of the first elastic moderator material and the second elastic moderator material may be a carbon-containing C material, such as graphite, paraffin, polyethylene, etc. Such materials have excellent mechanical properties, and the moderation ratio is second only to deuterium D and oxygen O.

[0054] For some embodiments in which the detector assembly 40 includes a scintillator detector, for example, the scintillator material of the detector assembly 40 includes at least one of sodium iodide NaI and bismuth germanate BGO, the use of C-rich materials near the neutron source 10 and the detector may result in the appearance of significant neutron capture gamma peaks, neutron inelastic gamma peaks, neutron capture gamma single escape peaks, neutron inelastic gamma single escape peaks and neutron capture gamma double escape peaks of the C element in the background (i.e., when there is no material to be tested) gamma spectrum measured by the material composition analysis system, which may affect the measurement accuracy of some analyzed elements that rely on the positions of these energy peaks.

[0055] Figure 2 Schematic diagram of carbon C related peaks in the background γ spectrum obtained according to some embodiments of the material composition analysis system disclosed in the present invention. Figure 2It can be seen that once a large amount of C-containing materials are used as the moderator material, three peaks of 4.945 MeV, 4.44 MeV and 3.93 MeV will be introduced. According to research, for equipment using crystals such as NaI or BGO as detector materials, this will affect the measurement accuracy of the analyzed elements that rely on the positions of these three energy peaks. These analyzed elements are, for example, neon Ne (γ peak energy 4.374 MeV), magnesium Mg (γ peak energy 3.917 MeV), phosphorus P (γ peak energy 3.900 MeV), barium Ba (γ peak energy 4.096 MeV), lanthanum La (γ peak energy 4.847 MeV and 5.098 MeV), cerium Ce (γ peak energy 4.766 MeV), uranium U (γ peak energy 4.060 MeV), etc.

[0056] Based on the above research, in some embodiments of the present disclosure, at least one of the first elastic slowing material and the second elastic slowing material is an elastic slowing material that does not contain carbon elements. Among them, the first elastic slowing material can be an elastic slowing material that does not contain carbon elements, the second elastic slowing material can be an elastic slowing material that does not contain carbon elements, or both the first elastic slowing material and the second elastic slowing material are elastic slowing materials that do not contain carbon elements.

[0057] In this way, the counting rate of carbon C related peaks can be effectively reduced to improve the analysis accuracy of analyzed elements such as neon Ne, magnesium Mg, phosphorus P, barium Ba, lanthanum La, cerium Ce, uranium U, etc. This can further improve the economic benefits of enterprises such as mining, batching, smelting, etc.

[0058] Regarding the selection of the elastic moderator material that does not contain carbon, in some embodiments, the elastic moderator material that does not contain carbon may include a material that does not contain carbon C and contains hydrogen H, deuterium D, and a lithium isotope with a mass number of 7. 7 Li, beryllium Be, boron isotope with mass number 11 11 An elastic moderating material of at least one of B and oxygen O.

[0059] Among these elastically moderated materials, hydrogen H has the highest elastic scattering cross section, and the material containing hydrogen H and no carbon C has the strongest moderation ability. In terms of moderation ratio, the most preferred material is the material containing deuterium D and no carbon C, followed by the material containing oxygen O, beryllium Be, and boron isotope with mass number 11. 11 B. Lithium isotope with mass number 7 7 Materials of Li and hydrogen H.

[0060] From the perspective of economy, it is most economical to choose a material that does not contain carbon C and contains hydrogen H. From the perspective of mechanical processing performance, beryllium Be has the best mechanical processing performance.

[0061] Select lithium isotope with mass number 7 7When Li material is used as a moderator, considering the lithium isotope with mass number 6 6 Li undergoes a (n, t) reaction and strongly absorbs thermal neutrons, so not only does the material contain no carbon C, but it also does not contain lithium isotopes with a mass number of 6. 6 Li.

[0062] Select a boron isotope with mass number 11 11 When the material of B is used as a moderator, considering the boron isotope with mass number 10 10 B undergoes (n, α) reaction and strongly absorbs thermal neutrons, so not only does the material contain no carbon C, but it also does not contain the boron isotope with mass number 10. 10 B.

[0063] Through the above research and analysis, in some embodiments, the elastic moderator material without carbon element 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 dry powder, it actually contains about 95% water, hence the name "dry water").

[0064] Compared to boron isotopes that require isotopic 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 moderation effect.

[0065] Figure 3 Schematic diagram of the structure principle of the second moderator or the third moderator in some embodiments of the material composition analysis system according to the present disclosure. Figure 3 For the embodiment in which at least one of the first elastic moderator material and the second elastic moderator material uses at least one of water H2O, heavy water D2O and dry water as the elastic moderator material, in order to enable such fluid or fluid-like material to be maintained at a corresponding position, in some embodiments, at least one of the second moderator structure 22 and the third moderator structure 23 includes a container 20b, and the container 20b is configured to contain and seal the elastic moderator material 20a that does not contain carbon elements, and the thermal neutron capture cross section of the material of the container 20b does not exceed 0.3b.

[0066] The container 20b can hold a fluid or fluid-like elastic moderator such as water H2O, heavy water D2O or dry water, and the thermal neutron capture cross section of the material does not exceed 0.3b, which can reduce the probability of neutron capture by the container 20b to reduce neutron loss. When the measurement accuracy can meet the requirements, a material containing carbon C can be appropriately selected as the material of the container 20b.

[0067] In some embodiments, the material of the container includes at least one of magnesium Mg, zirconium Zr, aluminum Al, and aluminum oxide Al2O3. These materials do not contain carbon C, which can reduce the influence of the energy peak of C on other analyzed elements, and have higher material strength.

[0068] refer to Figure 1 In some embodiments, the material composition analysis system further includes a neutron absorption structure 50, which is located between the detector assembly 40 and the third moderator structure 23 and is used to absorb neutrons. For the detector assembly 40 that performs composition analysis by gamma spectrum, 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.

[0069] The neutron absorbing structure 50 may be made of lithium isotope having a mass number of 6. 6 Li material, which can effectively absorb thermal neutrons and basically does not emit gamma rays, thereby reducing the interference of neutrons on the detector assembly 40 and the interference of gamma rays that are not generated by the interaction between the inspected material IM and neutrons.

[0070] refer 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 in the shielding material 60.

[0071] The shielding material 60 can be used to shield neutrons, gamma rays or other radiation in the material composition analysis system from the external environment to avoid polluting the external environment. The shielding material 60 can be made of lead Pb, tungsten W, concrete, boron-containing polyethylene, etc.

[0072] In the above embodiments, by burying at least part of the neutron source 10 and the neutron moderation structure 20 in the material to be inspected IM, the utilization rate of the neutrons emitted by the neutron source 10 can be effectively improved, and the structure of the material composition analysis system can be made compact to reduce space occupancy.

[0073] On this basis, reference Figure 1 In some embodiments, the detector assembly 40 includes a first detector 41. The first detector 41 is located in the material containing cavity 30 so that the first detector 41 is buried in the inspected material IM.

[0074] exist Figure 1 In the embodiment, the neutron source 10, the neutron moderation structure 20 as a whole and the first detector 41 are all buried in the inspected material IM. This structure can make the material composition analysis system more compact and reduce space occupation to a greater extent.

[0075] refer to Figure 1 In some embodiments, the material holding chamber 30 is configured to form a flow channel for the inspected material IM, and the detector assembly 40 includes two groups of first detectors 41, which are located on both sides of the neutron source 10 along a first direction dr1, and the first direction dr1 is parallel to the extension direction of the flow channel.

[0076] exist Figure 1 In the embodiment, the material to be inspected IM can flow along the material containing chamber 30 along the axis direction drawn vertically, so that the material composition analysis system can perform material composition analysis on the continuously flowing material to be inspected IM in different time ranges. Two groups of first detectors 41 are arranged on both sides of the neutron source 10 along the first direction dr1, and each group may include one or more first detectors 41. The two groups of first detectors 41 can capture characteristic signals at the front and rear sides of the neutron source 10 along the first direction dr1 to increase the probability of detecting the characteristic signals.

[0077] refer to Figure 1 In some embodiments, a wear-resistant structure 70 is provided at the portion where the first detector 41 contacts the inspected material IM. The wear-resistant structure 70 can minimize the wear of the first detector 41 when the first detector 41 contacts the inspected material IM or contacts and rubs against the inspected material IM, so as to improve the reliability and service life of the first detector 41. The wear-resistant structure 70 can be in the form of a wear-resistant coating or a wear-resistant shell, and can be made of a material with a relatively high hardness and a relatively limited impact on the analysis accuracy of the material composition analysis system, such as aluminum oxide (Al2O3) ceramics.

[0078] Figure 4 Schematic diagram of the structure of some other embodiments of the material composition analysis system according to the present disclosure. Figure 4 In some embodiments, the material holding chamber 30 is configured to form a flow channel for the inspected material IM, and at least a portion of the third moderator structure 23 is coated on the inner wall of the material holding chamber 30. Preferably, the third moderator structure 23 is coated on the entire inner wall of the material holding chamber 30. The detector assembly 40 includes a second detector 42, and the second detector 42 is located on a side of the third moderator structure 23 away from the neutron source 10 along the second direction dr2. The second direction dr2 intersects with the extension direction of the flow channel.

[0079] exist Figure 4 In the embodiment, the third moderator structure 23 may include a tubular portion covering the inner wall of the material holding chamber 30 to form a tubular flow channel with the second moderator structure 22 and the shielding material 60. The third moderator structure 23 may moderate neutrons and absorb excess neutrons.

[0080] exist Figure 4In the embodiment, the material IM to be inspected can flow in the material containing chamber 30 along the vertically drawn axis direction, so that the material composition analysis system can perform material composition analysis on the continuously flowing material IM to be inspected in different time ranges. 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. The second direction dr2 here can intersect with the extension direction of the flow channel, for example, perpendicular to the first direction dr1 or at an acute angle or an obtuse angle.

[0081] refer to Figure 4 In some embodiments, the detector assembly 40 includes two groups of second detectors 42, and the two groups of second detectors 42 are located on both sides of the neutron source 10 along the second direction dr2. There may be more than one second direction dr2, that is, the two groups of second detectors 42 may be located on both sides of the neutron source 10 in one or more second directions dr2 intersecting the first direction dr1.

[0082] For the two groups of second detectors 42, each group may include one or more second detectors 42. The two groups of second detectors 42 may capture characteristic signals at the front and rear sides of the neutron source 10 along the second direction dr2 to increase the probability of detecting the characteristic signals. Figure 4 The center lines drawn vertically are symmetrical or staggered.

[0083] In this embodiment, multiple second detectors 42 can be arranged in the third moderation structure 23 as needed, so that these detectors are distributed around the material IM to be measured, which can effectively increase the probability of characteristic signals being detected, which is conducive to improving measurement accuracy. Moreover, this arrangement is conducive to the component analysis of the material IM to be measured in the form of fluid or fluid-like.

[0084] Figure 5 Schematic diagram of the structure of some other embodiments of the material composition analysis system according to the present disclosure. Figure 5 ,and Figure 4 Compared with the embodiment shown, in some embodiments, the detector assembly 40 further includes a first detector 41, which is located in the material receiving cavity 30 so that the first detector 41 is buried in the inspected material IM. The third moderator structure 23 also has a portion located between the first detector 41 and the second moderator structure 22.

[0085] In this embodiment, the first detector 41 and the second detector 42 are located outside the neutron source 10 and the neutron moderator 20 in the first direction dr1 and the second direction dr2. This can further increase the probability of detecting characteristic signals while achieving a compact structure, thereby achieving higher analysis accuracy.

[0086] In the above embodiment, the detectors included in the detector assembly 40 can be accommodated in a container containing a 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.

[0087] For example, a material IM is a magnesium ore, and the material composition analysis system is used to analyze the Mg content in the Mg ore. The particle size of the Mg ore is 50 mm. Figure 4 In the arrangement structure shown in the figure, the first elastic moderator material of the second moderator structure 22 and the second elastic moderator material of the third moderator structure 23 are both made of H2O, the inelastic moderator material of the first moderator structure 21 is made of bismuth Bi, and the neutron absorption structure 50 is made of lithium isotope with a mass number of 6. 6 Li material. The thickness of the first moderator structure 21 is 2-3 cm, the thickness of the second moderator structure 22 is 2-3 cm, the thickness of the third moderator structure is 8-10 cm, and the thickness of the neutron absorption structure 50 is 3-4 cm. According to the test, the analysis accuracy of the Mg component can be improved from 0.45% to 0.30%.

[0088] Take another scenario where the material IM to be inspected is phosphate ore, and the material composition analysis system is used to analyze the P content in the phosphate ore. The particle size of the inspected phosphate ore is 1 mm. Figure 5 In the arrangement structure shown in the figure, the first elastic moderator material of the second moderator structure 22 and the second elastic moderator material of the third moderator structure 23 are both made of H2O, the inelastic moderator material of the first moderator structure 21 is made of bismuth Bi, and the neutron absorption structure 50 is made of lithium isotope with a mass number of 6. 6 Li material. The thickness of the first moderator structure 21 is 2-3 cm, the thickness of the second moderator structure 22 is 2-3 cm, the thickness of the third moderator structure is 8-10 cm, and the thickness of the neutron absorption structure 50 is 3-4 cm. After testing, the analysis accuracy of the P component is improved from 0.90% to 0.60%.

[0089] So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.

[0090] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A material composition analysis system, comprising: A neutron source (10) configured to generate neutrons for acting on an inspected material (IM); A neutron moderation structure (20), surrounding the neutron source (10), and configured to moderate neutrons generated by the neutron source (10); A material containing chamber (30) configured to contain the inspected material (IM); and A detector assembly (40) configured to capture characteristic signals generated by the inspected material (IM) after being bombarded by neutrons; Wherein, at least a portion of the neutron moderating structure (20) is located in the material containing cavity (30), so that at least a portion of the neutron moderating structure (20) is buried in the inspected material (IM).

2. The material composition analysis system according to claim 1, wherein: The neutron moderating structure (20) comprises: A first moderator structure (21) comprising an inelastic moderator material; and A second moderator structure (22), comprising a first elastic moderator material, and arranged around the first moderator structure (21); The first moderator structure (21) is located between the neutron source (10) and the second moderator structure (22), and the second moderator structure (22) is located in the material containing cavity (30), so that the second moderator structure (22) is at least partially buried in the inspected material (IM).

3. The material component analysis system according to claim 2, wherein: The neutron moderating structure (20) further comprises: The third moderator structure (23) comprises a second elastic moderator material and is located between the detector assembly (40) and the second moderator structure (22).

4. The material component analysis system according to claim 3, wherein: At least one of the first elastic moderator material and the second elastic moderator material is an elastic moderator material that does not contain carbon elements.

5. The material composition analysis system according to claim 4, wherein: The elastic moderator material containing no carbon element includes no carbon and contains hydrogen H, deuterium D, and lithium isotope with a mass number of 7. 7 Li, beryllium Be, boron isotope with mass number 11 11 An elastic moderating material of at least one of B and oxygen O.

6. The material component analysis system according to claim 5, wherein: The elastic moderator material not containing carbon element comprises at least one of water H2O, heavy water D2O and dry water.

7. The material composition analysis system according to claim 4, wherein: At least one of the second moderator structure (22) and the third moderator structure (23) comprises a container, wherein the container is configured to contain and seal the elastic moderator material that does not contain carbon elements, and 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 material of the container includes at least one of magnesium Mg, zirconium Zr, aluminum Al and aluminum oxide Al2O3.

9. The material component analysis system according to claim 1, wherein: The detector assembly (40) comprises: The first detector (41) is located in the material containing cavity (30), so that the first detector (41) is buried in the inspected material (IM).

10. The material component analysis system according to claim 9, wherein: The material containing cavity (30) is configured to form a flow channel for the inspected material (IM), and the detector assembly (40) comprises two groups of first detectors (41), wherein the two groups of first detectors (41) are located on both sides of the neutron source (10) along a first direction (dr1), and the first direction (dr1) is parallel to an extension direction of the flow channel.

11. The material component analysis system according to claim 9, wherein: A wear-resistant structure (70) is provided at a portion of the first detector (41) that contacts the inspected material (IM).

12. The material component analysis system according to claim 3, wherein: The material containing cavity (30) is configured to form a flow channel for the inspected material (IM), at least a portion of the third moderation structure (23) is coated on the inner wall of the material containing cavity (30), and the detector assembly (40) comprises: a second detector (42) located along a second direction (dr2) on a side of the third moderation structure (23) away from the neutron source (10), The second direction (dr2) intersects with an extension direction of the flow channel.

13. The material component analysis system according to claim 12, wherein: The detector assembly (40) comprises two groups of second detectors (42), wherein the two groups of second detectors (42) are located on both sides of the neutron source (10) along the second direction (dr2).

14. The material component analysis system according to claim 12, wherein: The detector assembly (40) further comprises: A first detector (41) is located in the material containing cavity (30), so that the first detector (41) is buried in the inspected material (IM); The third moderator structure (23) further comprises a portion located between the first detector (41) and the second moderator structure (22).

15. The material composition analysis system according to claim 3, further comprising: The neutron absorption structure (50) is located between the detector assembly (40) and the third moderation structure (23) and is used for absorbing neutrons.

16. The material component analysis system according to claim 1, wherein: The scintillator material of the detector assembly (40) comprises at least one of sodium iodide NaI and bismuth germanate BGO.

17. The material composition analysis system according to claim 1, further comprising: Shielding material (60) for radiation shielding; Wherein, the neutron source (10), the neutron moderating structure (20) and the detector assembly (40) are located inside the shielding material (60).

18. The material component analysis system according to claim 1, wherein: A wear-resistant structure (70) is provided at a portion of the neutron moderation structure (20) that contacts the inspected material (IM).

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