Centrifugal soil heavy metal detection device and method

Abstract

The invention relates to a centrifugal soil heavy metal detection device and method. The centrifugal soil heavy metal detection device comprises a box body; the rotating part comprises a rotating driving part and a rotating disc, the rotating driving part is fixed in the box body, the rotating driving part is connected with the rotating disc so as to drive the rotating disc to rotate around the rotation axis relative to the box body, and the rotating disc is used for placing soil to be detected; the laser spectrum assembly comprises a laser device and a spectrograph which are connected to the box body and located above the rotating disc, and the light emitting side of the laser device and the collecting side of the spectrograph both face the rotating disc. Under the action of centrifugal force provided by the turntable, surface substances of the to-be-detected sample are sequentially exposed in the height direction, so that substance components in different depth areas of the to-be-detected sample can be detected by matching with starting of the laser and the spectrograph after each rotation of the turntable, and the automation degree of the detection device is improved; and the detection result is more comprehensive and automatic.

Description

Technical Field

[0001] The present invention relates to the technical field of soil component detection, and particularly to a centrifugal soil heavy metal detection device and method. Background Art

[0002] Laser-induced breakdown spectroscopy (LIBS) technology is a method based on the interaction between laser and matter to generate characteristic spectra, and then realize the analysis of the composition and concentration of matter. This technology focuses a high-energy laser on the surface of the sample, induces the generation of plasma on the surface of the matter, and then uses a spectrometer to analyze the specific wavelength light emitted by the plasma, so as to determine the composition and content of the matter in the sample. LIBS technology can analyze solid, liquid, and gaseous samples. Almost all elements will emit characteristic spectral lines after being excited to form plasma, so LIBS can analyze most elements.

[0003] In the technology for detecting the composition and content of fine particles, soil and other fine particle samples are often placed on the detection platform of a laser-induced breakdown spectrometer. After the high-energy laser emitted by the laser in LIBS hits the top surface of the soil, the area of the soil surface layer irradiated by the laser can be vaporized into plasma. Subsequently, the plasma in the excited state migrates from the high-energy state back to the low-energy state, emits light with characteristic wavelengths, and is received and analyzed by the spectrometer. Relying on the sensitivity of the spectrometer to spectral analysis, the information such as the peak position and peak intensity in the light spectrum emitted by the plasma is analyzed to identify the types and corresponding contents of the elements in the soil, and the identification, classification, qualitative and quantitative analysis of the soil can be carried out, so as to determine the heavy metal elements contained in the soil.

[0004] However, the defect of current similar detection technologies is that the laser can only irradiate the soil surface to form plasma, and the laser cannot irradiate the bottom part of the detected soil. The results analyzed by the spectrometer cannot cover the components in the non-top layer area of the soil. When the components such as heavy metals in the soil are unevenly distributed, it is easy to lead to incomplete detection results of the soil.

[0005] In this regard, if it is necessary to fully detect a fixed amount of soil samples to be detected, generally, the soil samples need to be placed on the detection platform in small amounts multiple times, and the detection platform needs to be cleaned each time, resulting in a long detection cycle and unable to achieve rapid detection. For the method of placing a fixed amount of soil to be detected on the detection platform at once and scraping off the surface samples with a handheld push plate after each laser irradiation and spectral collection to expose the bottom samples successively, the detection personnel need to frequently open the detection box, which cannot create a single detection environment and is likely to interfere with the accuracy of the detection results due to the intervention of external factors. At the same time, since the sample to be detected is located in the high-energy laser irradiation area, the hand should not approach frequently, otherwise it is easy to cause experimental accidents. Summary of the Invention

[0006] Based on this, it is necessary to provide a centrifugal soil heavy metal detection device and method to make the detection results more comprehensive and automated.

[0007] A centrifugal soil heavy metal detection device includes:

[0008] A box body;

[0009] A rotating member, including a rotation driving member and a turntable. The rotation driving member is fixed in the box body, and the rotation driving member is connected to the turntable to drive the turntable to rotate relative to the box body around the self-rotation axis. The turntable is used to place the soil to be detected; and

[0010] A laser spectroscopy assembly, including a laser and a spectrometer connected to the box body and located above the turntable. The light-emitting side of the laser and the collection side of the spectrometer both face the turntable.

[0011] For the centrifugal soil heavy metal detection device provided in the embodiments of the present application, the sample to be detected (such as soil) is placed on the turntable, and the light-emitting side of the laser faces the sample to be detected to irradiate it with a high-energy laser beam, prompting the outermost surface of the sample to be detected to form a plasma in an excited state. When the plasma drops from the high-energy state to the low-energy state, it emits a beam with a characteristic wavelength, which is then absorbed and analyzed by the spectrometer, thereby obtaining the composition of the outermost layer of the sample to be detected.

[0012] Subsequently, the rotation driving member is controlled to drive the turntable to rotate. Due to the particle characteristics of the sample to be detected and the action of rotational centrifugal force, the sample particles located in the upper layer will slide and disperse toward the circumferential side under the centrifugal action, thereby exposing the sample particles located in the lower layer. Furthermore, the laser is used again to irradiate the surface layer of the sample to be detected currently with high-energy laser to generate new plasma, and the spectrometer is used again to analyze the substance components therein, so as to realize the layer-by-layer component detection of the sample along the depth direction. The surface layer substances of the sample to be detected are sequentially exposed along the height direction under the action of the centrifugal force provided by the turntable, so that the laser and the spectrometer can cooperate to detect the substance components in different depth regions of the sample to be detected, improve the automation degree of the detection device, and make the detection results more comprehensive and rapid. It avoids excessive contact between the detection personnel and the sample to be detected, helps to create a single detection environment, and can improve the safety of the detection process, thus bringing great advantages to the automated design of comprehensive detection.

[0013] In one embodiment, a partition wall in a ring structure protrudes from one side of the turntable close to the laser spectroscopy assembly. The midpoint of the partition wall is located on the self-rotation axis line, and the area surrounded by the partition wall is used to place the sample to be detected. In this embodiment, the sample to be detected is placed in the area surrounded by the partition wall, so that the partition wall can enclose at least a part of the bottom layer of the sample to be detected. When the rotation speed of the turntable is too fast, the sample to be detected will not be completely thrown out in all directions, but will be restricted by the partition wall. Further, the setting of the partition wall can prevent the particles on the surface layer and near the surface layer of the sample to be detected from dispersing too fast or even completely in all directions, so that the components in multiple depth regions of the sample to be detected can be fully detected.

[0014] In one embodiment, the thickness of the partition wall is less than or equal to 3 mm, and the diameter of the area surrounded by the partition wall is less than or equal to 5 cm. In this embodiment, the thickness and diameter of the partition wall are restricted. The thickness is not too thick, and the enclosed area is not too large. The samples placed in the enclosed area and stacked can disperse more reasonably along the radial direction and fall outside the partition wall when rotating with the turntable, and will not accumulate on the partition wall to hinder the sliding of the upper samples.

[0015] In one embodiment, the barrier wall includes a first barrier wall and a second barrier wall, the first barrier wall and the second barrier wall are both annular structures, and the centers of the two coincide, the second barrier wall surrounds the first barrier wall and is radially spaced from the first barrier wall, and the area surrounded by the first barrier wall and the area between the first barrier wall and the second barrier wall are used to place soil. In this embodiment, by surrounding the two barrier walls, at least a part of the sample can be confined within the first barrier wall and between the first barrier wall and the second barrier wall, and will not completely escape from the laser irradiation range and the spectrometer recognition range due to centrifugal action, and at the same time, the speed at which the sample spreads to the surroundings due to centrifugal force can be further restricted.

[0016] In one embodiment, the height of the first barrier wall is higher than that of the second barrier wall. The gradient barrier wall can make the samples between the first barrier wall and the second barrier wall still partially exceed the height of the second barrier wall after the samples are completely dispersed, so that the laser can irradiate this part of the samples; after the turntable rotates further, the samples between the first barrier wall and the second barrier wall and flush with the height of the second barrier wall are exposed, so that the laser can further irradiate this part of the samples, and the detection of the samples in the radial and height directions is realized, and the samples at multiple designated positions in the radial direction of the turntable can always be retained and will not be completely dispersed due to excessive rotation speed.

[0017] In one embodiment, the bottom height of the area enclosed by the barrier wall is higher than the height of the periphery of the barrier wall. In this embodiment, there will not be too many samples confined in the area enclosed by the barrier wall, but more samples will be located at a position higher than the barrier wall, and thus can be spread out to the surroundings due to centrifugal force and expose the lower layer samples, so that the laser can irradiate more samples at different heights.

[0018] In one embodiment, the centrifugal soil heavy metal detection device further includes a translation assembly, the translation assembly includes a guide rail and a translation driver connected to each other, the guide rail is arranged in the housing and is perpendicular to the rotation axis of the turntable, the laser and the spectrometer are slidably arranged on the guide rail and are connected to the translation driver, and the translation driver is used to drive the laser and the spectrometer to move along the guide rail. By arranging the translation assembly to drive the laser and the spectrometer, the laser can move in the radial direction of the turntable to irradiate more areas of the sample, and can not only perform layer-by-layer detection in the depth direction of the middle area of ​​the sample, but also perform layer-by-layer detection in the depth direction at other radial positions.

[0019] A centrifugal soil heavy metal detection method is applied to the centrifugal soil heavy metal detection device described in any of the above embodiments, and the method comprises:

[0020] S11: The laser performs a first laser irradiation on the soil to be detected located on the turntable;

[0021] S12: The spectrometer first collects the spectral data of the plasma formed on the soil to be detected;

[0022] S13: The turntable is driven to rotate by the rotation driving member;

[0023] S14: The laser performs a second laser irradiation on the soil to be detected located on the turntable;

[0024] S15: The spectrometer second collects the spectral data of the plasma formed on the soil to be detected.

[0025] For the centrifugal soil heavy metal detection device provided by the embodiment of the present application, first place the sample to be detected on the turntable, and then control the laser to irradiate the sample to be detected with a high-energy laser beam for the first time, first prompting the outermost surface of the sample to be detected to form a plasma in an excited state. When the plasma drops from the high-energy state to the low-energy state, it emits a beam with a characteristic wavelength, which is thus absorbed and analyzed by the spectrometer for the first time, so as to obtain the composition of the outermost layer of the sample to be detected.

[0026] Subsequently, control the rotation driving member to drive the turntable to rotate. Due to the particle characteristics of the sample to be detected and the action of the rotational centrifugal force, the sample particles located on the upper layer will slide and disperse to the periphery under the centrifugal action, thereby exposing the sample particles located on the lower layer; furthermore, the laser irradiates the surface layer of the current sample to be detected with a high-energy laser again to generate a new plasma, and the spectrometer analyzes the material composition of the plasma at this time through spectral information again, so as to realize the layer-by-layer composition detection of the sample along the depth direction. Through the action of the centrifugal force provided by the turntable, the surface layer substances of the sample to be detected are sequentially exposed along the height direction, the material composition of different depth regions of the sample to be detected can be detected, the automation degree of the detection device is improved, and the detection result is more comprehensive.

[0027] A centrifugal soil heavy metal detection method is applied to the above-mentioned centrifugal soil heavy metal detection device, and the method includes:

[0028] S21: The laser performs a first laser irradiation on the soil to be detected located at the center of the turntable;

[0029] S22: The spectrometer first collects the spectral data of the plasma formed on the soil to be detected;

[0030] S23: The laser is driven to move along the radial periphery of the turntable by the translation driving member;

[0031] S24: The laser performs a second laser irradiation on the soil to be detected that has a radial distance from the center of the turntable.

[0032] S25: The spectrometer secondarily collects spectral data of the plasma formed on the soil to be detected.

[0033] For the centrifugal soil heavy metal detection method in this embodiment, the translation driving member can move the laser along the radius of the sample, so that different radial regions of the sample can be irradiated. At the same time, in cooperation with the spectrometer for analysis, the three-dimensional space of the sample can be detected, and the detection result can be more comprehensive.

[0034] In one embodiment, after S25, it further includes:

[0035] S26: Drive the turntable to rotate through the rotation driving member;

[0036] S27: Drive the laser to move above the center of the turntable through the translation driving member;

[0037] S28: The laser performs a third laser irradiation on the soil to be detected located at the center of the turntable;

[0038] S29: The spectrometer thirdly collects spectral data of the plasma formed on the soil to be detected. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The following further describes the present invention in conjunction with the drawings and embodiments, where:

[0040] Figure 1 is a schematic diagram of a centrifugal soil heavy metal detection device provided by an embodiment of the present application;

[0041] Figure 2 is a schematic diagram of the initial distribution state of the sample on the turntable provided by an embodiment of the present application;

[0042] Figure 3 is Figure 2 a schematic diagram of the intermediate distribution state of the sample on the turntable in the embodiment;

[0043] Figure 4 is Figure 2 a schematic diagram of the final distribution state of the sample on the turntable in the embodiment;

[0044] Figure 5 is a schematic diagram of the initial distribution state of the sample on the turntable provided by an embodiment of the present application;

[0045] Figure 6 is Figure 5 a schematic diagram of the intermediate distribution state of the sample on the turntable in the embodiment;

[0046] Figure 7 For Figure 5 Schematic diagram of the final distribution state of the samples in the embodiment on the turntable;

[0047] Figure 8 Schematic diagram of the centrifugal soil heavy metal detection device provided by an embodiment of the present application;

[0048] Figure 9 Flow chart of the centrifugal soil heavy metal detection method provided by an embodiment of the present application;

[0049] Figure 10 Flow chart of the centrifugal soil heavy metal detection method provided by another embodiment of the present application;

[0050] Reference numerals:

[0051] Box 10; Rotation driving member 21; Turntable 22; Laser 31; Spectrometer 32; Partition wall 40; First region 401; Second region 402; First baffle 41; Second baffle 42; Guide rail 51; Translation driving member 52; Sample to be detected 60. Detailed implementation manners

[0052] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the following describes the detailed implementation manners of the present invention with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0054] In the present invention, unless otherwise clearly specified or limited, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] In the present invention, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0056] In the technology for detecting the component content of fine particulate matter, fine particulate matter samples such as soil are often placed on the detection platform of a laser-induced breakdown spectrometer. After high-energy laser emitted by the laser hits the top surface of the soil, the area of the soil surface layer irradiated by the laser can be vaporized into plasma. Subsequently, the plasma in the excited state migrates from the high-energy state back to the low-energy state, emits light with characteristic wavelengths, and is received and analyzed by the spectrometer. Relying on the sensitivity of the spectrometer for spectral analysis, the information such as the peak position and peak intensity in the light spectrum emitted by the plasma is analyzed to identify the types and corresponding contents of elements in the soil, so as to determine the heavy metal elements contained in the soil. However, the defect of current similar detection technologies is that the laser can only irradiate the soil surface to form plasma, and the laser cannot irradiate the bottom part of the detected soil. The results analyzed by the spectrometer cannot cover the components in the non-top layer area of the soil. When the components such as heavy metals in the soil are unevenly distributed, it is likely to lead to incomplete detection results of the soil.

[0057] Reference Figure 1, embodiments of the present application provide a centrifugal soil heavy metal detection device, which includes: a box body 10; a rotating member, including a rotation driving member 21 and a turntable 22, the rotation driving member 21 is fixed in the box body 10, the rotation driving member 21 is connected to the turntable 22 to drive the turntable 22 to rotate relative to the box body 10 around the self-rotation axis, and the turntable 22 is used to place the soil to be detected; and a laser spectroscopy component, including a laser 31 and a spectrometer 32 that are connected to the box body 10 and located above the turntable 22, and the light-emitting side of the laser 31 and the collection side of the spectrometer 32 both face the turntable 22. The turntable 22 can be circular or other common shapes. The rotation driving member 21 includes a motor and a gear set, the motor meshes with the gear set, and the gear set meshes with the bottom or side of the turntable 22, so that the rotation of the turntable 22 can be controlled by the output of the motor. A light-shielding cover plate is provided on the box body 10, and when the laser 31 and the spectrometer 32 are working, the light-shielding cover plate needs to be closed to prevent environmental interference. The box body 10 can be made into a portable detection device by adding a handle.

[0058] For the centrifugal soil heavy metal detection device in the embodiments of the present application, the sample to be detected (such as soil) is placed on the turntable 22 to form a conical stack. The light-emitting side of the laser 31 faces the sample to be detected to irradiate it with a high-energy laser beam, prompting the outermost surface of the sample to be detected to form a plasma in an excited state. When the plasma drops from the high-energy state to the low-energy state, it emits a beam with a characteristic wavelength, which is then absorbed and analyzed by the spectrometer 32 to obtain the composition of the outermost substance of the sample to be detected.

[0059] Subsequently, the rotation driving member 21 is controlled to drive the turntable 22 to rotate. Due to the particle characteristics of the sample to be detected and the action of rotational centrifugal force, since the upper-layer sample particles are mainly affected by air resistance and friction with the lower-layer particles, the resistance they receive is smaller. Moreover, the sample particles at the top of the conical pile are located at a higher position and have greater potential energy, and are thus more likely to slide downward due to gravity and are easier to move and slide down. The lower-layer sample particles are simultaneously affected by the particles above and below them, and the resistance they receive is greater, making them relatively less likely to move. As a result, the sample particles in the upper layer will slide and disperse toward the circumferential side under the centrifugal action, exposing the sample particles in the lower layer. When the turntable 22 rotates, these powders are more likely to slide downward due to gravity and are simultaneously pushed outward by the centrifugal force. Subsequently, the laser 31 is used again to perform high-energy laser irradiation on the surface layer of the sample to be detected currently to generate a new plasma, and the spectrometer 32 is used again to analyze the substance components therein, thereby realizing the layer-by-layer component detection of the sample along the depth direction. Through the action of the centrifugal force provided by the turntable 22, the surface substances of the sample to be detected are sequentially exposed along the height direction, and in combination with the laser 31 and the spectrometer 32, the substance components in different depth regions of the sample to be detected can be detected, making the detection results more comprehensive and rapid. In addition, for a fully automatic test platform, by coordinately controlling the rotation speed of the turntable 22, the laser emission of the laser 31, and the spectrum acquisition of the spectrometer 32 through an intelligent drive algorithm for the centrifugal soil heavy metal detection device, human intervention operations can be completely avoided during the detection process, which helps to create a single detection environment and improve the safety of the detection process, bringing great advantages to the automated design of comprehensive detection.

[0060] Continue to refer to Figure 1 , in order to prevent the sample to be detected from dispersing too quickly when rotating with the turntable 22 and enable the laser 31 and the spectrometer 32 to act gradually and slowly downward, in some embodiments, a partition wall 40 with an annular structure can be formed to protrude on one side of the turntable 22 close to the laser spectroscopy assembly. The midpoint of the partition wall 40 is located on the self-rotation axis line, and the area surrounded by the partition wall 40 (the first area 401) is used to place the sample to be detected. The setting of this partition wall 40 can limit the sample to be detected within the first area 401 surrounded by the partition wall 40 from dispersing outward, preventing the top-layer sample from sliding down faster due to the dispersion of the bottom-layer sample, and avoiding the particles on the surface layer and near the surface layer of the sample to be detected from dispersing too quickly or even completely in all directions, so that the components in multiple depth regions of the sample to be detected can be fully detected gradually.

[0061] The purpose of each rotation of the turntable 22 is to disperse the surface layer sample and expose the next layer of sample. However, in actual detection, due to the diversity of samples to be detected, for example, there are different possibilities for the particle size and the weight of soil particles in different types of soil samples. Therefore, it is difficult to configure corresponding turntable rotation speeds for different types of soil samples. In this regard, a fixed rotation speed mode can be applied to the turntable each time. Specifically, to make the outer layer sample particles slide off, it is required that the centrifugal force and the gravity component received by the outermost layer sample particles are sufficient to overcome the friction force between them and the next layer of sample particles. Under ideal conditions, it is necessary to satisfy g·sinθ + a·cosθ ≥ μ(g·cosθ - a·sinθ), where a is the radial centrifugal acceleration received by the sample particles, g is the acceleration due to gravity, θ is the inclination angle of the slope formed by the surface layer sample relative to the plane where the turntable 22 is located, μ is the friction coefficient between soil particles, and the centrifugal acceleration is a = ω 2 R, ω is the rotation speed of the sample particles, which is generally the rotation speed of the current turntable, and R is the distance of the sample particles relative to the turntable rotation axis. By setting the average radius (such as 3 cm), the average slope inclination angle (such as 45°) of the overall sample to be detected on the turntable 22, and the friction coefficient between soil particles (such as μ = 1), the rotation speed ω required to cause the surface layer sample particles to slide off can be roughly calculated. The specific values of each parameter can be adjusted according to the actual application scenario. However, it should be noted that there is no need to pursue too precise rotation speed of the turntable 22. A slight difference between the rotation speed of the turntable 22 and the theoretical value usually does not have a great impact on the detection result. Since the components between samples in adjacent areas generally tend to be the same, as long as the turntable 22 can make the surface layer sample particles and the adjacent near-surface particles slide off after each rotation and gradually expose the sample particles in the deeper layer, a comprehensive detection effect can also be obtained after multiple detections.

[0062] To prevent the instantaneous rotation speed of the turntable 22 from being too fast when starting each time, resulting in the sample rotating relative to the turntable 22 at the beginning and causing the centrifugal force not to be transmitted to the outermost layer sample particles, in one embodiment, the rotation speed of the turntable 22 can start from 0 and gradually increase to ω each time it rotates.

[0063] Furthermore, considering the influence of the humidity of the soil sample on the dispersion speed, a drying machine (not shown in the figure) can be set in the centrifugal soil heavy metal detection device, that is, the drying machine is set in the box body 10, and the air outlet of the drying machine faces the area where the sample to be detected is located. The drying machine blows the sample to be detected 60 each time the turntable 22 rotates to dry its surface layer, preventing the sample to be detected 60 at the bottom from being affected by humidity and affecting its dispersion speed when rotating with the turntable 22, or even the problem of being unable to disperse.

[0064] Specifically, refer to Figures 2 to 5 , Figure 2Schematic diagram of the initial distribution state of the sample provided by an embodiment of the present application on the turntable 22. At this time, the sample 60 to be detected is placed on the turntable 22 as a whole in a conical shape, covering the partition wall 40. In the initial state, the laser 31 can be vertically directed towards the center position of the turntable 22, that is, roughly corresponding to the highest point of the sample 60 to be detected, namely the a layer. As the turntable 22 rotates successively, each rotation can cause a part of the surface layer sample to spread out and expose the next layer of the sample. For example, after successive rotations, the sample 60 to be detected can successively expose layers b, c, and d from the top vertex in the depth direction.

[0065] Reference Figure 3 , after the second rotation of the turntable 22, the c layer of the sample 60 to be detected is exposed. Thus, the c layer can be irradiated by the laser 31, and the characteristic light emitted by the generated plasma can be received and analyzed by the spectrometer 32, so as to determine the composition at the position of the c layer.

[0066] Furthermore, reference can be made to Figure 4 , as the turntable 22 continues to rotate, the sample 60 to be detected that exceeds the top of the partition wall 40 can be spread out and slide to the periphery of the partition wall 40. At this time, the sample 60 to be detected exposes the d layer area equivalent to the height of the partition wall 40. Then, the d layer can be irradiated by the laser 31, and the characteristic light emitted by the generated plasma can be received and analyzed by the spectrometer 32, so as to determine the composition at the position of the d layer.

[0067] As the turntable 22 rotates multiple times, the height of the sample 60 to be detected will gradually decrease. At this time, the beam focus of the laser 31 may not be located on the surface of the current sample, but at a position higher than the sample surface, resulting in the inability to effectively form plasma on the sample surface. Therefore, in one embodiment, the laser 31 includes a focusing drive member and a focusing lens group. The focusing drive member is connected to the focusing lens group to control the movement of the focusing lens group along the optical axis direction of the laser 31, and further control the position of the focus of the emitted laser beam, so that the focus is always located on the surface of the current sample 60 to be detected. The driving mode of the focusing drive member can be, for example, manually adjusted by the detection personnel; or after each rotation of the turntable 22, the focusing drive member drives the focusing lens group to gradually move from the starting position to the maximum stroke, so that the laser spot can reach the sample surface at least at some moments.

[0068] In one embodiment, the spreading speed of the sample 60 to be detected can be controlled by controlling the thickness of the partition wall 40, so as to avoid the spreading speed of the sample 60 to be detected being too slow and affecting the detection efficiency. Specifically, the thickness of the partition wall 40 can be made less than or equal to 3 mm, and the diameter of the area surrounded by the partition wall 40 is less than or equal to 5 cm. In this embodiment, the thickness and diameter of the partition wall 40 are restricted. The thickness will not be too thick, and the surrounded area will not be too large. The sample 60 to be detected, which is placed in the surrounded area and is conical, can spread more reasonably in the radial direction and fall outside the partition wall 40 when rotating with the turntable 22, and will not accumulate on the upper end surface of the partition wall 40 to prevent the samples of the next layer from sliding down.

[0069] In addition to detecting layer by layer the middle area of the sample 60 to be detected, it is also possible to further detect layer by layer the samples at the edge. For example, a driving device is arranged in the box body 10 to drive the laser 31, and the irradiation position of the laser beam emitted by the laser 31 is controlled. The driving device is connected between the box body 10 and the laser 31, and the spectrometer 32 can also be arranged on the driving device to move synchronously with the laser 31. In one embodiment, the driving device includes a rotating member. A rotating member is arranged in the box body 10 to control the rotation of the laser 31, so that the light-emitting side of the laser 31 can be switched between the positions facing the center and the edge of the sample. After each rotation of the turntable 22, after the laser 31 irradiates the middle area of the sample to form a plasma, the spectrometer 32 receives and analyzes the characteristic light rays; then the laser 31 is controlled by the rotating member to change its orientation to face the edge area of the sample, so as to perform a high-energy laser irradiation on this area again, and the spectrometer 32 receives and analyzes the characteristic light rays again. By repeating this process, the middle area and the edge area of the sample can be detected layer by layer, so that a more comprehensive component analysis of the sample can be carried out in three-dimensional space.

[0070] Further, in one embodiment, a retaining plate (not shown in the figure) is provided at the edge of the turntable 22. The retaining plate is annular to surround the partition wall 40. A radial spacing area is formed between the retaining plate and the partition wall 40. When the samples on the turntable 22 spread around due to centrifugal force, they will be restricted in this radial spacing area by the retaining plate. Then, the laser 31 can perform high-energy laser irradiation on the samples in this radial spacing area again under the action of the driving device to form a plasma, and cooperate with the spectrometer 32 for detection and identification, further enhancing the comprehensiveness of the detection.

[0071] Continue to refer to Figure 1, in another embodiment, the driving device includes a translation assembly. The translation assembly includes a guide rail 51 and a translation driving member 52 connected to each other. The guide rail 51 is disposed in the box body 10 and perpendicular to the rotation axis of the turntable 22. The laser 31 and the spectrometer 32 are slidably disposed on the guide rail 51 and connected to the translation driving member 52. The translation driving member 52 is used to drive the laser 31 and the spectrometer 32 to move along the guide rail 51. The orthographic projection of the guide rail 51 on the turntable 22 may pass through the center of the turntable 22. By providing the translation assembly to drive the laser 31 and the spectrometer 32, the laser 31 can move in the radial direction of the turntable 22 to irradiate more areas of the sample, and not only can the depth direction of the middle area of the sample be detected layer by layer, but also the depth direction of the sample at other radial positions can be detected layer by layer.

[0072] Reference Figures 5 to 7 , in order to more effectively detect the samples 60 to be detected distributed in the radial direction of the turntable 22, in some embodiments, the partition wall 40 may include a first partition wall 41 and a second partition wall 42. Both the first partition wall 41 and the second partition wall 42 are in an annular structure, and the centers of the two coincide. The second partition wall 42 surrounds the first partition wall 41 and is spaced from the first partition wall 41 in the radial direction. The area surrounded by the first partition wall 41 and the area between the first partition wall 41 and the second partition wall 42 are used for placing soil. The annular structure can be a symmetric structure such as a circular ring or a regular polygon. A radial spacing distance of 0.5 cm to 1.5 cm can be formed between the first partition wall 41 and the second partition wall 42 to ensure that the width of the second area 402 is sufficient for the laser 31 to irradiate easily. In this embodiment, through the surrounding arrangement of the two partition walls, at least a part of the sample can be restricted within the first partition wall 41 (the first area 401) and between the first partition wall 41 and the second partition wall 42 (the second area 402), and will not completely fall out of the irradiation range of the laser 31 and the recognition range of the spectrometer 32 due to the centrifugal force. At the same time, since the sample particles at the bottom are restricted from spreading, the sample at the top will not spread outwards too quickly, thereby restricting the scattering speed of the sample when rotating with the turntable 22.

[0073] Reference Figure 6 , after most of the samples higher than the first partition wall 41 in the first area 401 are scattered around, the height of the samples in the second area 402 will be higher than the second partition wall 42 at the beginning, that is, point e in the figure. Therefore, the laser 31 can irradiate point e at this moment and cooperate with the spectrometer 32 to detect this area. Subsequently, reference Figure 7 , as the turntable 22 rotates further, the samples higher than the second partition wall 42 in the second area 402 will spread out, exposing the bottom f layer. Similarly, based on the fact that the laser 31 can irradiate point f at this moment and cooperate with the spectrometer 32 to detect this area, the depth detection of the second area 402 can be realized by this method.

[0074] Further, in one embodiment, the height of the first retaining wall 41 is higher than that of the second retaining wall 42, thereby forming a gradient structure with a higher inner part and a lower outer part. The retaining walls arranged in a gradient manner enable the samples within the area of the first retaining wall 41 and exceeding its height to still have a part exceeding the height of the second retaining wall 42 after being completely dispersed, so that the laser 31 can irradiate this part of the samples; after the turntable 22 rotates further, the samples located between the first retaining wall 41 and the second retaining wall 42 and flush with the height of the second retaining wall 42 are exposed, so that the laser 31 can further irradiate this part of the samples, realizing the detection of the samples in the radial and height directions, and the samples at multiple specified positions in the radial direction of the turntable 22 can always be retained and will not be completely dispersed due to too high a rotation speed.

[0075] Reference Figure 8 , the bottom height of the area enclosed by the partition wall 40 in one embodiment is higher than the height of the periphery of the partition wall 40. Specifically, the area enclosed by the partition wall 40 is the first area 401, the bottom of the first area 401 is a plane, and the bottom of the first area 401 is higher than the plane of the turntable 22. Since the samples in the first area 401 enclosed by the partition wall 40 cannot be dispersed due to rotation, the bottom thereof cannot be irradiated by the laser and there is a dead zone, and the samples cannot be fully detected. In this embodiment, not too many samples will be restricted within the first area 401 enclosed by the partition wall 40, but more are located at positions higher than the partition wall 40, and thus can be more dispersed around due to centrifugal force and expose the lower-layer samples, so that the laser 31 can irradiate the samples at more different height positions. In addition, in order to facilitate the cleaning of the samples 60 to be detected in the first area 401, the partition wall 40 can be in a bowl-shaped structure with a narrow bottom and a wide top, so as to facilitate thorough cleaning of the bottom corner positions and not easily cause detection interference to the samples placed next time.

[0076] In one embodiment, in order to further improve the cleaning convenience of the turntable 22, the turntable 22 is detachably connected to the rotation driving member 21. Specifically, for example, a non-circular symmetric card slot is provided at the bottom of the turntable 22, and a card block with a shape adapted thereto is provided on the rotation driving member 21, and the turntable 22 is buckled onto the card block of the rotation driving member 21 from above to achieve fixation. After the detection is completed, it can be detached for cleaning.

[0077] Reference Figure 9 , based on the centrifugal soil heavy metal detection device in any of the above embodiments, the present application further provides a centrifugal soil heavy metal detection method cooperating therewith, and the method at least includes the following steps:

[0078] S11: The laser 31 performs the first laser irradiation on the soil to be detected located on the turntable 22;

[0079] After the tester places the sample 60 to be tested at the center of the turntable 22 to form a conical shape, the high-energy laser beam emitted by the laser 31 can be controlled by the buttons on the box body 10 to irradiate the sample.

[0080] S12: The spectrometer 32 collects the spectral data of the plasma formed on the soil to be tested for the first time;

[0081] After the laser beam irradiation, the device can start the spectrometer 32 to collect and analyze the characteristic spectrum emitted by the plasma formed on the surface of the sample once, so as to complete the detection of the outermost layer components of the sample at the initial time.

[0082] S13: Drive the turntable 22 to rotate through the rotation driving member 21;

[0083] After steps S11 and S12 are executed, the device instructs the rotation driving member 21 to control the turntable 22 to rotate at a preset speed, so that the surface layer sample slides off and spreads out, exposing the next layer of the sample.

[0084] S14: The laser 31 performs a second laser irradiation on the soil to be tested located on the turntable 22;

[0085] S15: The spectrometer 32 collects the spectral data of the plasma formed on the soil to be tested for the second time.

[0086] After step S15, S13 - S15 can be repeatedly executed, so as to realize the multi-layer detection of the sample 60 to be tested in the depth direction.

[0087] For the device provided in the embodiment of the present application, during the detection, the sample 60 to be tested is first placed on the turntable 22, and then the laser 31 is controlled to irradiate the sample 60 to be tested with a high-energy laser beam for the first time, first promoting the formation of plasma in the excited state on the outermost surface of the sample 60 to be tested. When the plasma drops from the high energy state to the low energy state, it emits a beam with a characteristic wavelength, which is thus absorbed and analyzed by the spectrometer 32 for the first time, so as to obtain the composition of the outermost layer substance of the sample 60 to be tested.

[0088] Subsequently, the rotation driving member 21 is controlled to drive the turntable 22 to rotate. Due to the particle characteristics of the sample to be detected 60 and the action of the rotational centrifugal force, the sample particles located in the upper layer will slide and disperse toward the circumferential side under the centrifugal action, thereby exposing the sample particles located in the lower layer. Furthermore, the laser 31 is used again to perform high-energy laser irradiation on the surface layer of the current sample to be detected to generate a new plasma, and the spectrometer 32 is used again to analyze the material composition of the plasma at this time through spectral information, so as to realize the layer-by-layer composition detection of the sample along the depth direction. The surface layer substances of the sample to be detected 60 are sequentially exposed along the height direction under the action of the centrifugal force provided by the turntable 22, and the material compositions of different depth regions of the sample to be detected 60 can be detected, improving the automation degree of the detection device and making the detection results more comprehensive and automated.

[0089] Reference Figure 10 , for the centrifugal soil heavy metal detection device provided with the translation driving member 52 as described above, the centrifugal soil heavy metal detection method provided by the embodiment of the present application may at least include the following steps:

[0090] S21: The laser 31 performs the first laser irradiation on the soil to be detected located at the center of the turntable 22;

[0091] S22: The spectrometer 32 collects the spectral data of the plasma formed on the soil to be detected for the first time;

[0092] S23: The translation driving member 52 is used to drive the laser 31 to move along the radial periphery of the turntable 22;

[0093] After step S22, the translation driving member 52 can be used to continuously or gradually move along the radial direction, and then the light spot of the laser 31 is controlled to gradually move along the radial direction of the sample to be detected 60.

[0094] S24: The laser 31 performs the second laser irradiation on the soil to be detected having a radial distance from the center of the turntable 22;

[0095] During the movement of the laser 31 in step S23, continuous or intermittent multiple irradiations are controlled to form a plasma on the surface of the sample to be detected 60 on the light spot path.

[0096] S25: The spectrometer 32 collects the spectral data of the plasma formed on the soil to be detected for the second time.

[0097] Through the cyclic execution of steps S23 to S25, the surface components of the sample in the radial direction can be detected and identified. For the centrifugal soil heavy metal detection method in this embodiment, the translation driving member 52 can move the laser 31 along the radial direction of the sample, so as to irradiate different radial regions of the sample. At the same time, it is analyzed in cooperation with the spectrometer 32, and the three-dimensional space of the sample can be detected, and the detection result can be more comprehensive and automated.

[0098] Further, after each execution of step S25 or when step S23 is repeatedly executed to move the laser spot of the laser 31 to the edge close to the partition wall 40, the rotation driving member 21 can be further cooperated to implement the following steps:

[0099] S26: Drive the turntable 22 to rotate by the rotation driving member 21;

[0100] S27: Drive the laser 31 to move above the center of the turntable 22 by the translation driving member 52;

[0101] S28: The laser 31 performs a third laser irradiation on the soil to be detected located at the center of the turntable 22;

[0102] S29: The spectrometer 32 collects the spectral data of the plasma formed on the soil to be detected for the third time.

[0103] Through steps S26 to S29, after the upper layer of the sample 60 to be detected is detected, the layer can slide and disperse under the action of centrifugal force to expose the next layer of the sample, and then the components of the next layer of the sample can be detected. After step S29 is executed, S23 to S25 can be repeatedly executed to detect the radial uniformity of the next layer of the sample. By cycling S23 to S29 in sequence, the components of each region in the radial and depth directions of the sample 60 to be detected can be detected, and the heavy metal components in each region of the soil sample can be fully determined, making the detection more comprehensive and reliable.

[0104] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combinations of these technical features do not conflict, they should be considered as the scope described in this specification.

[0105] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A centrifugal soil heavy metal detection device, characterized in that: include: Box; The rotating member includes a rotating driving member and a rotating disk, wherein the rotating driving member is fixed in the housing, the rotating driving member is connected to the rotating disk to drive the rotating disk to rotate relative to the housing around the rotation axis, and the rotating disk is used to place the soil to be tested; and The laser spectrum component comprises a laser and a spectrometer connected to the housing and located above the turntable, wherein the light emitting side of the laser and the collecting side of the spectrometer are both facing the turntable.

2. The centrifugal soil heavy metal detection device according to claim 1, characterized in that: A side of the turntable close to the laser spectrum component protrudes to form a ring-shaped barrier wall, the midpoint of which is located on the rotation axis, and the area surrounded by the barrier wall is used to place soil to be detected.

3. The centrifugal soil heavy metal detection device according to claim 2, characterized in that: The thickness of the barrier wall is less than or equal to 3 mm, and the diameter of the area surrounded by the barrier wall is less than or equal to 5 cm.

4. The centrifugal soil heavy metal detection device according to claim 2, characterized in that: The barrier wall includes a first barrier wall and a second barrier wall, both of which are annular structures, and the centers of the two coincide, the second barrier wall surrounds the first barrier wall and is radially spaced from the first barrier wall, and the area surrounded by the first barrier wall and the area between the first barrier wall and the second barrier wall are used to place soil.

5. The centrifugal soil heavy metal detection device according to claim 4, characterized in that: The first blocking wall is higher than the second blocking wall.

6. The centrifugal soil heavy metal detection device according to claim 2, characterized in that: The bottom height of the area enclosed by the barrier wall is higher than that of the rotating disk.

7. The centrifugal soil heavy metal detection device according to claim 1 or 4, characterized in that: It also includes a translation assembly, which includes a connected guide rail and a translation driver. The guide rail is arranged in the box and is perpendicular to the rotation axis of the turntable. The laser and the spectrometer are slidably arranged on the guide rail and are connected to the translation driver. The translation driver is used to drive the laser and the spectrometer to move along the guide rail.

8. A centrifugal soil heavy metal detection method, characterized in that: The centrifugal soil heavy metal detection device according to any one of claims 1 to 7, the method comprising: S11: the laser irradiates the soil to be tested on the rotating disk for the first time; S12: the spectrometer collects spectrum data of the plasma formed on the soil to be tested for the first time; S13: driving the turntable to rotate by the rotary driving member; S14: the laser irradiates the soil to be tested on the rotating disk for a second time; S15: The spectrometer collects spectrum data of the plasma formed on the soil to be tested for the second time.

9. A centrifugal soil heavy metal detection method, characterized in that: Applied to the centrifugal soil heavy metal detection device according to claim 7, the method comprises: S21: the laser irradiates the soil to be tested located at the center of the turntable for the first time; S22: the spectrometer collects spectrum data of the plasma formed on the soil to be tested for the first time; S23: driving the laser to move along the radial periphery of the turntable by the translation driving member; S24: the laser irradiates the soil to be inspected at a radial distance from the center of the rotating disk for a second time; S25: The spectrometer collects spectrum data of the plasma formed on the soil to be tested for the second time.

10. The centrifugal soil heavy metal detection method according to claim 9, characterized in that: S25 and later also include: S26: driving the turntable to rotate by the rotary driving member; S27: driving the laser to move above the center of the turntable by the translation driving member; S28: the laser irradiates the soil to be tested located at the center of the turntable for the third time; S29: The spectrometer collects spectrum data of the plasma formed on the soil to be tested for the third time.

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