A waste rare earth recycling method based on a feature marking strategy

Abstract

This application belongs to the technical field of resource recovery, and discloses a method for recycling rare earths from waste based on a feature marking strategy, including using Raman spectroscopy analysis technology to identify useful waste containing rare earth compounds, obtaining a three-dimensional model, using X-ray fluorescence spectroscopy analysis technology to determine the distribution area of rare earth elements and mark it, cutting according to the marked three-dimensional model, retaining the part containing the rare earth element distribution area as the item to be refined, and finally refining rare earths from the item to be refined; this method first screens out useful waste containing rare earth compounds, then accurately locates the distribution area of rare earth elements on the useful waste and conducts targeted cutting and refining, improving the utilization rate of chemical reaction raw materials, reducing the refining cost, and shortening the refining time.

Description

Technical Field

[0001] This application relates to the technical field of resource recovery. Specifically, it relates to a method for recycling rare earths from waste based on a feature marking strategy. Background Art

[0002] Rare earths are known as the "industrial vitamins", which are important industrial raw materials and even more important strategic resources. Rare earths belong to recyclable resources. Under the conditions permitted by technology and economy, the rare earths contained in various waste materials containing rare earths can be recycled; on the contrary, if the waste materials containing rare earths are not properly disposed of, it may cause "secondary pollution". Therefore, identifying waste materials containing rare earths, clarifying their recycling value, and then carrying out recycling and reuse of them have important practical significance both from the perspective of resource conservation and environmental protection.

[0003] In actual industrial production, when recycling rare earths from waste materials containing rare earths (such as waste rare earth glass, waste circuit boards, etc.), the commonly used method is "detecting whether there are rare earth compounds (i.e., compounds containing rare earth elements) → estimating the overall rare earth content of the waste material → performing overall chemical reaction treatment on the waste material → rare earth purification". Although the process of this kind of method is simple, it has the following deficiencies: after detecting the rare earth content in the waste material, in the subsequent rare earth refining process, the entire waste material is subjected to chemical reaction treatment (that is, mixing the entire waste material with chemical reaction raw materials), and the rare earth compounds are not evenly distributed in the waste material (the current detection method does not characterize and mark the distribution of rare earths in the waste material). Therefore, although the entire waste material is subjected to chemical reaction treatment, in fact, only the part where the rare earth compounds aggregate really reacts with the chemical reaction raw materials. Therefore, the utilization rate of the chemical reaction raw materials is not high, which leads to high costs and long time consumption in the entire refining process (including the chemical reaction and purification processes).

[0004] In view of the above problems, the existing technology urgently needs to be improved. Summary of the Invention

[0005] The purpose of this application is to provide a method for recycling rare earths from waste based on a feature marking strategy, which can improve the utilization rate of chemical reaction raw materials, reduce the refining cost, and shorten the refining time.

[0006] This application provides a method for recycling rare earths from waste based on a feature marking strategy, which is used to recycle rare earths from plate-shaped waste materials, and includes the steps of:

[0007] A1. Using Raman spectroscopy analysis technology, identifying useful waste materials containing rare earth compounds from the recycled waste materials;

[0008] A2. Obtain the three-dimensional model of the useful waste;

[0009] A3. Use X-ray fluorescence spectrometry to determine the distribution areas of rare earth elements in the useful waste, and mark each rare earth element distribution area in the three-dimensional model;

[0010] A4. Cut the useful waste according to the marked three-dimensional model to retain the part containing the rare earth element distribution area as the item to be refined;

[0011] A5. Conduct rare earth refining on the item to be refined.

[0012] First, screen out the useful waste containing rare earth compounds, then accurately locate the distribution areas of rare earth elements on the useful waste and conduct targeted cutting and refining, which improves the utilization rate of chemical reaction raw materials, reduces the refining cost, and shortens the refining time.

[0013] Preferably, step A1 includes:

[0014] Obtain the Raman spectrogram data of the recycled waste, denoted as the first Raman spectrogram data;

[0015] Match the first Raman spectrogram data with each standard Raman spectrogram data in the first control database; the first control database contains the standard Raman spectrogram data corresponding to various rare earth compounds;

[0016] If the match is successful, determine that the corresponding waste is useful waste containing rare earth compounds, otherwise determine that the corresponding waste is useless waste without rare earth compounds.

[0017] By obtaining the Raman spectrogram data of the recycled waste and matching it with the standard Raman spectrogram data in the first control database, the useful waste containing rare earth compounds can be effectively identified, thus distinguishing the useless waste. This method ensures the accuracy and reliability of the identification process through spectral matching technology.

[0018] Optionally, step A2 includes:

[0019] Use a laser three-dimensional scanning device to scan the useful waste to obtain the corresponding three-dimensional model.

[0020] Optionally, step A2 includes:

[0021] Extract the corresponding three-dimensional model from the three-dimensional model library according to the category of the useful waste; the three-dimensional model library stores the pre-established three-dimensional models of various wastes.

[0022] Preferably, step A3 includes:

[0023] A301. Use an X-ray fluorescence spectrometer to scan the useful waste layer by layer to obtain the fluorescence spectrum of each scanned layer as the fluorescence spectrum to be identified; each scanned layer is arranged along the normal direction of the useful waste;

[0024] A302. Identify the rare earth content at each position of each scanned layer according to the fluorescence spectrum to be identified;

[0025] A303. Compare the identified rare earth content with a preset content threshold to determine the rare earth enrichment areas in each scanned layer;

[0026] A304. Determine the distribution areas of rare earth elements in the useful waste according to the distribution positions of the rare earth enrichment areas, and mark the distribution areas of rare earth elements in the three-dimensional model.

[0027] Using an X-ray fluorescence spectrometer to scan the waste layer by layer can obtain the fluorescence spectrum of each scanned layer. By analyzing these fluorescence spectra, the rare earth content at each position of each scanned layer can be identified. By comparing with a preset content threshold, the position of the rare earth enrichment area can be determined. According to the positions of these rare earth enrichment areas, the distribution areas of rare earth elements are marked in the three-dimensional model. The function of this technical feature is to accurately identify and mark the distribution areas of rare earth elements by layer-by-layer scanning and analyzing fluorescence spectra. Through the above solution, the technical problem of how to accurately identify and mark the distribution areas of rare earth elements in waste can be solved. The method of layer-by-layer scanning and fluorescence spectrum analysis ensures the precise positioning of the distribution of rare earth elements in waste, thereby improving the efficiency and accuracy of rare earth recovery.

[0028] Preferably, in step A301, use an X-ray beam with equal width to scan each scanned layer, form a plurality of scanning bands distributed side by side on each scanned layer, and one side of adjacent scanning bands is connected; record the fluorescence spectrum at the scanning position during the scanning process as the fluorescence spectrum to be identified.

[0029] Preferably, step A303 includes:

[0030] In each scanning band, regard the continuous area formed by connecting the scanning positions where the identified rare earth content is not less than the content threshold as the rare earth enrichment area.

[0031] Preferably, A304 includes:

[0032] Project each rare earth enrichment area along the normal direction onto the surface of the useful waste to obtain the corresponding projection area;

[0033] Perform a merging process on each projection area to merge the intersecting and / or overly spaced projection areas in the same scanning band;

[0034] Take each of the projected regions after the merging process as the distribution region of rare earth elements in the useful waste, and mark each rare earth element distribution region in the 3D model.

[0035] Preferably, step A4 includes:

[0036] A401. Obtain the coordinates of the four vertices of each rare earth element distribution region on the 3D model, denoted as vertex coordinates;

[0037] A402. Determine whether the rare earth element distribution regions are connected according to the vertex coordinates;

[0038] A403. If there are connected rare earth element distribution regions, take the region formed by connecting the connected rare earth element distribution regions as a connected region, and perform:

[0039] Envelope the connected region using a variety of envelope methods to obtain envelope regions corresponding to the various envelope methods;

[0040] Calculate the evaluation value of each envelope region according to the evaluation function related to the perimeter and area of the envelope region;

[0041] Determine the optimal envelope region of the connected region according to the evaluation value;

[0042] A404. If there is a connected region, cut out the corresponding optimal envelope region from the useful waste as one of the items to be refined;

[0043] A405. If there is an independent region, cut out the independent region from the useful waste as one of the items to be refined; the independent region is a rare earth element distribution region that is not connected to other rare earth element distribution regions.

[0044] Preferably, the evaluation function is:

[0045] ;

[0046] ;

[0047] ;

[0048] Wherein, is the evaluation value, is the weight value, and , is the effective perimeter ratio, is the effective area ratio, is the perimeter of the envelope region, is the total perimeter of the rare earth element distribution regions in the connected region, is the area of the connected region, is the area of the envelope region.

[0049] Beneficial effects: The waste rare earth recycling method based on the feature marking strategy provided by this application includes using Raman spectroscopy analysis technology to identify useful waste containing rare earth compounds, obtaining a three-dimensional model, using X-ray fluorescence spectroscopy analysis technology to determine the rare earth element distribution area and mark it, cutting according to the marked three-dimensional model, retaining the part containing the rare earth element distribution area as the item to be refined, and finally refining the rare earth from the item to be refined; this method first screens out useful waste containing rare earth compounds, then accurately locates the rare earth element distribution area on the useful waste and conducts targeted cutting and refining, improving the utilization rate of chemical reaction raw materials, reducing the refining cost, and shortening the refining time. Description of the Drawings

[0050] Figure 1 is the flowchart of the waste rare earth recycling method based on the feature marking strategy provided by the embodiment of this application.

[0051] Figure 2 is a schematic diagram of the marked result of the exemplary rare earth element distribution area.

[0052] Figure 3 is a schematic diagram of the first connection situation between adjacent rare earth element distribution areas.

[0053] Figure 4 is a schematic diagram of the second connection situation between adjacent rare earth element distribution areas.

[0054] Figure 5 is a schematic diagram of the envelope result of a kind of envelope method.

[0055] Figure 6 is a schematic diagram of the envelope result of another envelope method. Detailed Embodiments

[0056] Next, the technical solutions in the embodiments of this application will be clearly and completely described in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Usually, the components of the embodiments of this application described and shown here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but only represents the selected embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of this application.

[0057] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0058] In the field of rare earth recycling, traditional methods have the problem of insufficient characterization and marking of the rare earth distribution in waste, resulting in low utilization rate of chemical reaction raw materials, high refining cost, and long time consumption. The present application proposes a method for recycling rare earth from waste based on a feature marking strategy, aiming to solve this technical problem.

[0059] Please refer to Figure 1 , Figure 1 which is a method for recycling rare earth from waste based on a feature marking strategy in some embodiments of the present application, used to recycle rare earth from plate-shaped waste, and includes the steps:

[0060] A1. Using Raman spectroscopy analysis technology, identify useful waste containing rare earth compounds from the recycled waste;

[0061] A2. Obtain a three-dimensional model of the useful waste;

[0062] A3. Using X-ray fluorescence spectroscopy analysis technology, determine the rare earth element distribution areas in the useful waste, and mark each rare earth element distribution area in the three-dimensional model;

[0063] A4. Cut the useful waste according to the marked three-dimensional model to retain the part containing the rare earth element distribution area as the item to be refined;

[0064] A5. Carry out rare earth refining on the item to be refined.

[0065] This technical solution identifies waste containing rare earth compounds through Raman spectroscopy analysis technology to ensure that only useful waste is processed; obtains a three-dimensional model and uses X-ray fluorescence spectroscopy analysis technology to determine the distribution areas of rare earth elements to ensure accurate positioning of rare earth elements; marks the rare earth element distribution areas in the three-dimensional model for easy subsequent cutting; cuts according to the marks to retain the part containing rare earth elements, reducing unnecessary processing; carries out rare earth refining on the item to be refined to improve the rare earth recycling efficiency. Through these steps, the technical solution can efficiently recycle rare earth elements from plate-shaped waste and solve the problem of low utilization rate of chemical reaction raw materials caused by uneven distribution of rare earth elements.

[0066] In practical applications, waste materials containing rare earths, such as waste rare earth glass, waste circuit boards, etc., can effectively recover the rare earth elements therein after being processed through the above steps. First, Raman spectroscopy analysis technology is used to obtain the Raman spectrogram data of the recovered waste materials, and it is matched with the standard Raman spectrogram data in the control database to identify the useful waste materials containing rare earth compounds. Then, a laser three-dimensional scanning device is used to scan the useful waste materials or other methods are adopted to obtain their three-dimensional models. Next, an X-ray fluorescence spectrometer is used to scan the useful waste materials layer by layer to obtain the fluorescence spectra of each scanning layer, and to identify the rare earth content and distribution areas. After marking these areas in the three-dimensional model, cutting is performed according to the marks, and the parts containing rare earth elements are retained for refining. Through these steps, the method of the present application can efficiently recover rare earth elements from plate-shaped waste materials, solve the problem of low utilization rate of chemical reaction raw materials caused by uneven distribution of rare earth elements, improve the rare earth recovery efficiency, and reduce the refining cost and time.

[0067] In some embodiments, step A1 includes:

[0068] A101. Obtain the Raman spectrogram data of the recovered waste materials, denoted as the first Raman spectrogram data;

[0069] A102. Match the first Raman spectrogram data with the standard Raman spectrogram data in the first control database; the first control database contains the standard Raman spectrogram data corresponding to various rare earth compounds;

[0070] A103. If the match is successful, determine that the corresponding waste material is a useful waste material containing rare earth compounds, otherwise determine that the corresponding waste material is a useless waste material without rare earth compounds.

[0071] By obtaining the Raman spectrogram data of the recovered waste materials and matching it with the standard Raman spectrogram data in the first control database, useful waste materials containing rare earth compounds can be effectively identified, thus distinguishing useless waste materials. This method ensures the accuracy and reliability of the identification process through spectral matching technology. Through the above technical means, the technical problem of how to identify useful waste materials containing rare earth compounds from the recovered waste materials is solved. Specifically, by obtaining the Raman spectrogram data of the waste materials and matching it with the standard data, it can be accurately determined whether the waste materials contain rare earth compounds, thereby improving the efficiency and accuracy of waste material recovery.

[0072] Among them, existing Raman spectroscopy analysis equipment can be used to scan the recovered waste materials in a "dot matrix" (i.e., 3*3 or 4*4 dot matrix) manner to obtain the first Raman spectrogram data.

[0073] Raman spectroscopy analysis technology is a non-destructive testing technology based on the light scattering effect, which can provide molecular vibration information of substances. The first Raman spectrogram data is obtained by performing Raman spectroscopy measurements on the recycled waste. The standard Raman spectrogram data in the first control database is the pre-stored standard Raman spectrogram data of various rare earth compounds, which is obtained by performing Raman spectroscopy measurements on known rare earth compounds. The matching process is to compare the first Raman spectrogram data with the standard Raman spectrogram data in the first control database to judge the similarity between them. If the matching is successful, it indicates that the waste contains rare earth compounds; if the matching fails, it indicates that the waste does not contain rare earth compounds.

[0074] Specifically, various spectral matching algorithms can be adopted in the matching process, such as the least squares method, the correlation coefficient method, the principal component analysis method, etc. These algorithms can effectively compare the similarity of spectrogram data, so as to judge whether the waste contains rare earth compounds. In addition, the standard Raman spectrogram data in the first control database can be classified and stored according to different rare earth compounds to improve the efficiency and accuracy of the matching process.

[0075] This application uses Raman spectroscopy analysis technology and spectral matching algorithms to accurately judge whether the waste contains rare earth compounds. By accurately identifying the useful waste containing rare earth compounds, these wastes can be preferentially recycled and processed, improving the utilization rate of rare earth resources and avoiding unnecessary treatment of useless waste, thus reducing the cost in the recycling process.

[0076] In fact, the recycled waste can be classified in advance, and the waste of the same model can be grouped into one category, that is, before step A1, it also includes: A0. Classify the recycled waste and group the waste of the same model into one category. Thus, in step A1, several samples can be extracted from each category of waste for Raman spectroscopy analysis, and based on the analysis results of each sample, it can be finally judged whether each category of waste is useful waste; for example, for the same category of waste, if the proportion of the number of samples determined to be useful waste in the total number of samples of this category of waste is above a preset proportion threshold (which can be set according to actual needs), then it is finally determined that this category of waste is useful waste, otherwise, it is finally determined that this category of waste is useless waste. By this way, the workload of Raman spectroscopy analysis can be reduced and the recycling efficiency can be improved.

[0077] Among them, in step A2, various methods can be used to obtain the three-dimensional model of the useful waste.

[0078] For example, in some embodiments, step A2 includes:

[0079] Use a laser three-dimensional scanning device to scan useful waste to obtain the corresponding three-dimensional model.

[0080] By emitting laser beams and receiving reflected signals, the laser three-dimensional scanning device can capture the surface details of an object with high precision and generate a detailed three-dimensional model. This device has high scanning accuracy, ensuring that the generated three-dimensional model has high authenticity and accuracy. In practical applications, the scanning parameters can be adjusted according to the characteristics of different wastes to obtain the best scanning effect. Specifically, lasers with different wavelengths can be used, and the scanning speed and resolution can be adjusted, etc., to meet the scanning requirements of different types of wastes. For example, for wastes with a more complex surface, a high-resolution mode can be selected for scanning to ensure that all details are captured.

[0081] By using a laser three-dimensional scanning device to scan useful waste, it is possible to quickly and accurately obtain its three-dimensional model without damaging the waste. Compared with traditional manual measurement methods, the laser three-dimensional scanning device has higher accuracy and efficiency, which can greatly reduce measurement errors and time costs. Thus, it provides reliable basic data for subsequent marking and cutting of rare earth element distribution areas, ensuring the efficiency and accuracy of the rare earth recycling process.

[0082] Among them, each useful waste can be scanned to generate the corresponding three-dimensional model; but to reduce the total time-consuming for establishing three-dimensional models, a sample can also be extracted from each category of useful waste for scanning to generate a three-dimensional model, which serves as the general three-dimensional model for the corresponding category of useful waste.

[0083] For another example, in some embodiments, step A2 includes:

[0084] According to the category of useful waste, extract the corresponding three-dimensional model from the three-dimensional model library; the three-dimensional model library stores pre-established three-dimensional models of various types of wastes.

[0085] Through this solution, the three-dimensional model matching the category of useful waste can be quickly and accurately obtained from the three-dimensional model library, thereby improving the efficiency and accuracy of the rare earth recycling process.

[0086] During the implementation process, a multi-level three-dimensional model library can be established to classify, store, and manage different categories of wastes. For example, wastes can be divided into different categories such as electronic wastes and industrial wastes, and corresponding three-dimensional models can be established for each category. In practical applications, the system will automatically extract the corresponding three-dimensional model from the model library according to the input waste category. In addition, machine learning algorithms can be combined to continuously optimize the construction and maintenance of the model library to improve the accuracy and practicality of the model.

[0087] By introducing the extraction technology of the three-dimensional model library, this application can effectively solve the problem of resource waste caused by uneven distribution of rare earth elements in the prior art. Compared with the traditional method, the technical solution of this application realizes the accurate identification and treatment of waste, improves the efficiency of rare earth recovery, and reduces the cost.

[0088] Preferably, step A3 includes:

[0089] A301. Use an X-ray fluorescence spectrometer to scan the useful waste layer by layer to obtain the fluorescence spectrum of each scanning layer as the fluorescence spectrum to be identified; each scanning layer is arranged along the normal direction of the useful waste;

[0090] A302. Identify the rare earth content at each position of each scanning layer according to the fluorescence spectrum to be identified;

[0091] A303. Compare the identified rare earth content with the preset content threshold to determine the rare earth enrichment areas in each scanning layer;

[0092] A304. Determine the distribution area of rare earth elements in the useful waste according to the distribution positions of the rare earth enrichment areas, and mark the distribution areas of each rare earth element in the three-dimensional model.

[0093] By using an X-ray fluorescence spectrometer to scan the waste layer by layer, the fluorescence spectrum of each scanning layer can be obtained. By analyzing these fluorescence spectra, the rare earth content at each position of each scanning layer can be identified. By comparing with the preset content threshold, the position of the rare earth enrichment area can be determined. According to the positions of these rare earth enrichment areas, the distribution areas of rare earth elements are marked in the three-dimensional model. The function of this technical feature is to accurately identify and mark the distribution areas of rare earth elements through layer-by-layer scanning and analysis of fluorescence spectra. Through the above solution, the technical problem of how to accurately identify and mark the distribution areas of rare earth elements in waste can be solved. The method of layer-by-layer scanning and fluorescence spectrum analysis ensures the precise positioning of the distribution of rare earth elements in waste, thereby improving the efficiency and accuracy of rare earth recovery.

[0094] Among them, in step A301, an X-ray beam with equal width is used to scan each scanning layer, forming multiple juxtaposed scanning bands on each scanning layer, and one side of adjacent scanning bands is connected; during the scanning process, the fluorescence spectrum of the scanning position is recorded as the fluorescence spectrum to be identified.

[0095] For example Figure 2 in, each bar-shaped area f is a scanning band, and the width of each scanning band is equal to the width of the X-ray beam. When scanning each scanning layer, the X-ray beam can be moved along a serpentine movement path to improve the scanning continuity, thereby improving the scanning efficiency, but not limited to this.

[0096] Through this scanning method, it can be ensured that each scanning layer is comprehensively covered during the scanning process, and the fluorescence spectra at each position are accurately recorded, so as to effectively identify the distribution area of rare earth elements. Through this scanning method, the problem of how to effectively record and identify the distribution area of rare earth elements during the scanning process can be solved. Among them, some existing X-ray fluorescence spectrometers have a layer-by-layer scanning mode, and layer-by-layer scanning can be achieved by starting the layer-by-layer scanning program (i.e., "slicing" scanning). The layer-by-layer scanning method peels off the substances on the surface of the sample layer by layer and detects the elemental composition in each layer. This method can ensure that even if the rare earth elements are unevenly distributed in the sample, they can be accurately detected.

[0097] Among them, during the scanning process of the X-ray fluorescence spectrometer, the recorded fluorescence spectrum to be identified can be compared with the standard fluorescence spectrum of known rare earth elements, so as to determine whether the scanning position contains rare earth elements and the corresponding rare earth content. This is the prior art and will not be elaborated here.

[0098] Preferably, step A303 includes:

[0099] In each scanning band, the continuous area formed by connecting the scanning positions with the identified rare earth content not less than the content threshold (which can be set according to actual needs) is regarded as a rare earth enrichment area.

[0100] For example, in a scanning band, according to the scanning time sequence, the rare earth contents of each scanning position obtained are h1, h2, ……, hn, where n is the number of scanning positions in the scanning band. Assuming that h1 to h30 and h50 to h90 are all not less than the content threshold, then the rectangular area from the scanning position of h1 to the scanning position of h30 in this scanning band is regarded as a rare earth enrichment area, and the rectangular area from the scanning position of h50 to the scanning position of h90 in this scanning band is regarded as another rare earth enrichment area.

[0101] Sometimes, the distance between adjacent rare earth enrichment areas in the same scanning band is small (if the distance is less than the preset distance threshold, it is considered small, and the preset distance threshold can be set according to actual needs), then the corresponding rare earth enrichment areas and the areas between these rare earth enrichment areas can be merged into one rare earth enrichment area to reduce the number of rare earth enrichment areas and reduce the calculation amount of subsequent steps.

[0102] Among them, A304 includes:

[0103] Project each rare earth enrichment area onto the surface of the useful waste along the normal direction (i.e., the thickness direction of the useful waste) to obtain the corresponding projection area;

[0104] Perform a merging process on each projection area to merge the projection areas that intersect and / or have too small a distance in the same scanning band;

[0105] Each of the projected regions after the merging process is taken as the distribution region of rare earth elements in the useful waste, and each rare earth element distribution region is marked in the 3D model.

[0106] Through the above technical means, the problem of merging processing of the rare earth element distribution regions during projection can be effectively solved, enabling the accurate marking of the rare earth element distribution regions in the 3D model, thereby improving the efficiency and accuracy of rare earth recovery.

[0107] Each rare earth enrichment area is projected onto the surface of the useful waste along the normal direction, which can be achieved using projection algorithms. These algorithms can obtain the corresponding projected regions by calculating the projection positions of each rare earth enrichment area in the normal direction. For the merging process of the projected regions, image processing techniques, such as region merging algorithms, can be used to merge the projected regions that intersect and / or have too small a gap. Mark the projected regions after the merging process (including the projected regions formed by merging and the original projected regions that are not merged with other projected regions. For example, before the merging process, the projected region corresponding to a scan band includes regions 1, 2, 3, and 4. When regions 1 and 2 are merged into region 5 during the merging process, the projected regions after the merging process include regions 3, 4, and 5), which can be marked with different colors or marking symbols in the 3D model (as Figure 2 different colors are used to mark each rare earth element distribution region in, and the filled regions in the figure are the rare earth element distribution regions), for subsequent identification and processing.

[0108] Among them, the intersecting projected regions refer to the projected regions that at least partially overlap (including the case of sharing a common side on one side), and the projected regions with too small a gap refer to the projected regions whose gaps between each other are less than a preset gap threshold (which can be set according to actual needs).

[0109] Since each rare earth enrichment area is a rectangular region, and each rare earth element distribution region is also a rectangular region, as Figure 2 shown.

[0110] Specifically, step A4 includes:

[0111] A401. Obtain the coordinates of the four vertices of each rare earth element distribution region on the 3D model, denoted as vertex coordinates;

[0112] A402. Determine whether the rare earth element distribution regions are connected based on the vertex coordinates;

[0113] A403. If there are connected rare earth element distribution regions, then take the region formed by connecting the connected rare earth element distribution regions as a connected region, and execute:

[0114] Envelope the connected regions using multiple envelope methods to obtain the envelope regions corresponding to the multiple envelope methods;

[0115] Calculate the evaluation values of each envelope region according to the evaluation function related to the perimeter and area of the envelope region;

[0116] Determine the optimal envelope region of the connected region according to the evaluation value;

[0117] A404. If there is a connected region, cut out the corresponding optimal envelope region from the useful waste as one of the items to be refined;

[0118] A405. If there is an independent region, cut out the independent region from the useful waste as one of the items to be refined; the independent region is a rare earth element distribution region that is not connected to other rare earth element distribution regions.

[0119] Actually, if each rare earth element distribution region is cut separately, the overall cutting route is relatively long and the cutting time required is relatively more; cutting the connected rare earth element distribution regions as a whole can reduce the cutting time and improve the cutting efficiency.

[0120] Among them, in step A402, when the following conditions are met between two rare earth element distribution regions: (corresponding to the case of Figure 3 ) or (corresponding to the case of Figure 4 ), it is determined that the two rare earth element distribution regions are connected; among them, Figure 3 , Figure 4 in, , , , respectively represent the upper left vertex, lower left vertex, upper right vertex and lower right vertex of the left rare earth element distribution region in the two rare earth element distribution regions, , , , respectively represent the upper left vertex, lower left vertex, upper right vertex and lower right vertex of the right rare earth element distribution region in the two rare earth element distribution regions, is the y-axis coordinate of vertex , is the y-axis coordinate of vertex , is the y-axis coordinate of vertex , is the y-axis coordinate of vertex . Among them, the y-axis in the reference coordinate system xy is parallel to the length direction of the scanning belt (the up and down direction in Figure 2 , and the upward direction is positive), and the x-axis is horizontally perpendicular to the y-axis ( Figure 2in the left - right direction, with the right direction being positive).

[0121] Among them, in step A403, the region formed by connecting the adjacent rare - earth element distribution regions is regarded as the connected region, which means the region composed of successively adjacent rare - earth element distribution regions is regarded as the connected region. For example Figure 2 in the figure, the three rare - earth element distribution regions on the left are connected, so the region composed of these three rare - earth element distribution regions is regarded as a connected region.

[0122] Among them, the enclosing method may include: enclosing the connected region with the outer contour line of the connected region. At this time, the enclosing line is the outer contour line of the connected region, that is, a closed line formed by the non - common parts (non - overlapping parts) of all the side lines of each rare - earth element distribution region in the connected region. Since the enclosed region refers to the region surrounded by the enclosing line, the enclosed region obtained by using this method is the same as the connected region.

[0123] The enclosing method may also include: enclosing the connected region with the smallest circum - circle that can enclose the entire connected region (at this time, the enclosing line is this smallest circum - circle), enclosing the connected region with the smallest circum - rectangle that can enclose the entire connected region (at this time, the enclosing line is this smallest circum - rectangle, such as Figure 5 the dashed - line rectangle on the left) or enclosing the connected region with the smallest circum - ellipse that can enclose the entire connected region (at this time, the enclosing line is this smallest circum - ellipse).

[0124] The enclosing method may further include: taking the vertices of all rare - earth element distribution regions in the connected region as a point set, and using the convex - hull algorithm to determine the smallest convex polygon that contains all points in the point set, and enclosing the connected region with this smallest convex polygon (at this time, the enclosing line is this smallest convex polygon, such as Figure 6 the dashed - line polygon on the left). Among them, the convex - hull algorithm is a prior art and will not be elaborated here.

[0125] The enclosing method is not limited to this. In practical applications, the number and type of enclosing methods can be selected according to needs.

[0126] Among them, except for the method of enclosing the connected region with the outer contour line of the connected region, the enclosed regions obtained by other enclosing methods will introduce parts that do not contain rare - earth elements, resulting in processing these extra parts together during subsequent rare - earth extraction, which will increase the extraction cost and extraction time to a certain extent, but is beneficial to reducing the perimeter of the cutting region (i.e., the enclosed region), thereby reducing the cutting time. In this application, an evaluation function is used to comprehensively evaluate these two effects, so as to better balance the beneficial and adverse effects and achieve an improvement in comprehensive benefits.

[0127] Among them, the evaluation function for comprehensively evaluating the above two effects can be set according to actual needs. For example, in some embodiments, the evaluation function is:

[0128] ;

[0129] ;

[0130] ;

[0131] Among them, is the evaluation value, is the weight value, and (which can be adjusted specifically according to actual needs), is the effective perimeter ratio, is the effective area ratio, is the perimeter of the envelope area (i.e., the length of the envelope line), is the total perimeter of the rare earth element distribution area in the connected area, is the area of the connected area, is the area of the envelope area.

[0132] Using the above evaluation function, the larger it is, the better, so as to select the envelope area with the largest as the optimal envelope area; the influence degree of the envelope area perimeter and area on can be adjusted by adjusting

[0133] so as to better balance the influence of the two and achieve the improvement of comprehensive benefits.

[0134] Among them, and can be calculated according to the following formula:

[0135] ;

[0136] ;

[0137] Among them, w is the number of rare earth element distribution areas in the connected area, t is the width of the scanning band (i.e., the width of the rare earth element distribution area), is the y-axis coordinate of the upper edge of the i-th rare earth element distribution area, The y-axis coordinate of the lower edge of the i-th rare earth element distribution region, so that is the length of the i-th rare earth element distribution region.

[0138] When cutting, it is necessary to cut out the optimal envelope region and the independent rare earth element distribution regions (i.e., independent regions) as the items to be refined. For example Figure 2 in, the two rare earth element distribution regions on the right are not connected to other rare earth element distribution regions, so the two rare earth element distribution regions on the right are independent regions, and the three rare earth element distribution regions on the left form a connected region. Therefore, for Figure 2 this situation, it is necessary to cut out an optimal envelope region and two independent regions as the items to be refined.

[0139] Specifically, step A5 includes: performing a chemical reaction on the cut items to be refined and other chemical raw materials required for refining the target rare earth element, and then purifying the rare earth element from the substance obtained after the chemical reaction. The specific process is the prior art and will not be elaborated here.

[0140] In this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0141] The above are only the embodiments of the present application and are not used to limit the protection scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for recovering rare earths from waste, which is based on a feature marking strategy and is used to recover rare earths from plate-shaped waste, is characterized in that Including the steps: A1. Using Raman spectroscopy analysis technology, identify useful waste containing rare earth compounds from the recycled waste; A2. Obtain a three-dimensional model of the useful waste; A3. Using X-ray fluorescence spectroscopy analysis technology, determine the distribution regions of rare earth elements in the useful waste, and mark each rare earth element distribution region in the three-dimensional model; A4. Cut the useful waste according to the marked three-dimensional model to retain the part containing the rare earth element distribution region as the item to be refined; A5. Conduct rare earth refining on the item to be refined; Step A3 includes: A301. Use an X-ray fluorescence spectrometer to scan the useful waste layer by layer to obtain the fluorescence spectrum of each scanned layer as the fluorescence spectrum to be identified; each scanned layer is arranged along the normal direction of the useful waste; A302. Identify the rare earth content at each position of each scanned layer according to the fluorescence spectrum to be identified; A303. Compare the identified rare earth content with a preset content threshold to determine the rare earth enrichment regions in each scanned layer; A304. Determine the distribution regions of rare earth elements in the useful waste according to the distribution positions of the rare earth enrichment regions, and mark each rare earth element distribution region in the three-dimensional model; In step A301, scan each scanned layer with an X-ray beam of equal width to form a plurality of scanning bands distributed side by side on each scanned layer, and one side of adjacent scanning bands is connected; record the fluorescence spectrum of the scanning position during the scanning process as the fluorescence spectrum to be identified; Step A303 includes: In each scanning band, regard the continuous region formed by connecting the scanning positions with the identified rare earth content not less than the content threshold as the rare earth enrichment region; A304 includes: Project each rare earth enrichment region along the normal direction onto the surface of the useful waste to obtain the corresponding projection region; Perform a merging process on each projection region to merge the intersecting and / or overly spaced projection regions in the same scanning band; Regard each merged projection region as the distribution region of rare earth elements in the useful waste, and mark each rare earth element distribution region in the three-dimensional model.

2. The waste rare earth recovery method based on the feature marking strategy according to claim 1, characterized in that, Step A1 includes: Obtain the Raman spectrogram data of the recycled waste, denoted as the first Raman spectrogram data; Match the first Raman spectrogram data with each standard Raman spectrogram data in the first control database; the first control database contains the standard Raman spectrogram data corresponding to various rare earth compounds; If the match is successful, determine that the corresponding waste is useful waste containing rare earth compounds, otherwise determine that the corresponding waste is useless waste without rare earth compounds.

3. The waste rare earth recycling method based on the feature marking strategy according to claim 1, wherein Step A2 includes: Use a laser three-dimensional scanning device to scan the useful waste to obtain the corresponding three-dimensional model.

4. The waste rare earth recycling method based on the feature marking strategy according to claim 1, wherein Step A2 includes: Extract the corresponding three-dimensional model from the three-dimensional model library according to the category of the useful waste; the three-dimensional model library stores the pre-established three-dimensional models of various wastes.

5. The waste rare earth recovery method based on a feature marking strategy according to claim 1, characterized in that Step A4 includes: A401. Obtain the coordinates of the four vertices of each of the rare earth element distribution regions on the three-dimensional model, denoted as vertex coordinates; A402. Determine whether the rare earth element distribution regions are connected based on the vertex coordinates; A403. If there are connected rare earth element distribution regions, then take the region formed by connecting the connected rare earth element distribution regions as a connected area, and perform: Envelope the connected area using multiple envelope methods to obtain envelope areas corresponding to the multiple envelope methods; Calculate the evaluation values of the envelope areas according to the evaluation function related to the perimeter and area of the envelope areas; Determine the optimal envelope region of the connected area according to the evaluation values; A404. If there is a connected area, cut out the corresponding optimal envelope region from the useful waste as one of the items to be refined; A405. If there is an independent area, cut out the independent area from the useful waste as one of the items to be refined; the independent area is a rare earth element distribution region that is not connected to other rare earth element distribution regions.

6. The waste rare earth recycling method based on the feature marking strategy according to claim 5, characterized in that, The evaluation function is: ； ； ； Among them, is the evaluation value, is the weight value, and , is the effective perimeter ratio, is the effective area ratio, is the perimeter of the envelope area, is the total perimeter of the rare earth element distribution area in the connected area, is the area of the connected area, is the area of the envelope area.

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