Waste rare earth recovery method based on feature marking strategy

Abstract

The invention belongs to the technical field of resource recovery, and discloses a waste rare earth recovery method based on a feature marking strategy, which comprises the following steps: identifying useful wastes containing rare earth compounds by using a Raman spectrum analysis technology, obtaining a three-dimensional model, determining a rare earth element distribution area by using an X-ray fluorescence spectrum analysis technology, and marking, cutting is conducted according to the marked three-dimensional model, the part containing the rare earth element distribution area is reserved to serve as a to-be-refined object, and finally rare earth refining is conducted on the to-be-refined object. According to the method, the useful waste containing the rare earth compounds is screened out firstly, then the rare earth element distribution area is accurately positioned on the useful waste, targeted cutting and refining are conducted, the utilization rate of chemical reaction raw materials is increased, the refining cost is reduced, and the refining time is shortened.

Description

Technical Field

[0001] The present application relates to the technical field of resource recovery, and in particular to a method for recovering waste rare earths based on a feature marking strategy. Background Art

[0002] Rare earths are called "industrial vitamins". They are important industrial raw materials and important strategic resources. Rare earths are recyclable resources. All kinds of wastes containing rare earths can be recycled and reused under technical and economic conditions. On the contrary, if wastes containing rare earths are improperly disposed of, they may cause "secondary pollution". Therefore, it is of great practical significance to identify wastes containing rare earths, clarify their recycling value, and then recycle and reuse them, both from the perspective of resource conservation and environmental protection.

[0003] In actual industrial production, when recycling rare earths from waste containing rare earths (such as waste rare earth glass, waste circuit boards, etc.), the method commonly used is "conducting a test to see if there are rare earth compounds (i.e. compounds containing rare earth elements) → conducting an overall rare earth content estimation of the waste → conducting an overall chemical reaction treatment of the waste → rare earth purification". Although the process of this type of method is simple, it has the following shortcomings: after the rare earth content in the waste is detected, the subsequent rare earth refining process is to subject the entire waste to a chemical reaction treatment (i.e., the entire waste is mixed with the chemical reaction raw materials for reaction), and the rare earth compounds are not evenly distributed in the waste (the current detection method does not characterize and mark the distribution of rare earths in the waste). Therefore, although the entire waste is subjected to a chemical reaction treatment, in fact only the part where the rare earth compounds are concentrated actually reacts chemically with the chemical reaction raw materials, so the utilization rate of the chemical reaction raw materials is not high, which leads to high cost and long time consumption of the entire refining process (including chemical reaction and purification process).

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

[0005] The purpose of this application is to provide a waste rare earth recovery method based on a characteristic marking strategy, which can improve the utilization rate of chemical reaction raw materials, reduce refining costs, and shorten refining time.

[0006] The present application provides a waste rare earth recovery method based on a feature marking strategy, which is used to recover rare earth from plate-like waste, comprising the steps of: A1. Use Raman spectroscopy to identify useful waste containing rare earth compounds from recycled waste; A2. Obtaining a three-dimensional model of the useful waste; A3. Determine the distribution area of ​​rare earth elements in the useful waste using X-ray fluorescence spectrometry technology, and mark each rare earth element distribution area in the three-dimensional model; A4. Cutting the useful waste according to the marked three-dimensional model to retain the portion containing the rare earth element distribution area as the item to be refined; A5. Refining rare earths from the object to be refined.

[0007] First, useful waste containing rare earth compounds is screened out, and then the distribution area of ​​rare earth elements is accurately located on the useful waste, and targeted cutting and refining are carried out, which improves the utilization rate of chemical reaction raw materials, reduces refining costs, and shortens refining time.

[0008] Preferably, step A1 comprises: Obtaining Raman spectrum data of the recycled waste, recorded as first Raman spectrum data; Matching the first Raman spectrum data with each standard Raman spectrum data in a first reference database; the first reference database contains quasi-Raman spectrum data corresponding to a plurality of rare earth compounds; If the match is successful, the corresponding waste is determined to be useful waste containing rare earth compounds, otherwise the corresponding waste is determined to be useless waste not containing rare earth compounds.

[0009] By obtaining the Raman spectrum data of the recycled waste and matching it with the standard Raman spectrum data in the first reference database, useful waste containing rare earth compounds can be effectively identified, thereby distinguishing useless waste. This method ensures the accuracy and reliability of the identification process through spectral matching technology.

[0010] Optionally, step A2 includes: The useful waste is scanned by a laser three-dimensional scanning device to obtain a corresponding three-dimensional model.

[0011] Optionally, step A2 includes: According to the categories of the useful waste, the corresponding three-dimensional model is extracted from a three-dimensional model library; the three-dimensional model library stores pre-established three-dimensional models of various types of waste.

[0012] Preferably, step A3 comprises: A301. Scan the useful waste layer by layer using an X-ray fluorescence spectrometer 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; A302. Identify the rare earth content of each position of each scanning layer according to the fluorescence spectrum to be identified; A303. Compare the identified rare earth content and the preset content threshold to determine the rare earth-enriched area in each of the scanned layers; A304. Determine the distribution area of ​​rare earth elements in the useful waste according to the distribution position of each rare earth enrichment area, and mark each rare earth element distribution area in the three-dimensional model.

[0013] By scanning the waste layer by layer using an X-ray fluorescence spectrometer, the fluorescence spectrum of each scanning layer can be obtained. By analyzing these fluorescence spectrum lines, the rare earth content at each position of each scanning layer can be identified. By comparing with the preset content threshold, the location of the rare earth enriched area can be determined. According to the location of these rare earth enriched areas, the distribution area of ​​rare earth elements is marked in the three-dimensional model. The function of this technical feature is to accurately identify and mark the distribution area of ​​rare earth elements by scanning and analyzing the fluorescence spectrum layer by layer. Through the above scheme, the technical problem of how to accurately identify and mark the distribution area 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.

[0014] Preferably, in step A301, each of the scanning layers is scanned using an X-ray beam of equal width to form a plurality of scanning bands distributed in parallel on each of the scanning layers, with adjacent scanning bands connected at one side; during the scanning process, the fluorescence spectrum line at the scanning position is recorded as the fluorescence spectrum line to be identified.

[0015] Preferably, step A303 includes: In each of the scanning bands, a continuous area formed by scanning positions where the identified rare earth content is not less than the content threshold is taken as a rare earth enriched area.

[0016] Preferably, A304 includes: Projecting each of the rare earth-enriched areas along the normal direction onto the surface of the useful waste to obtain a corresponding projection area; Merging the projection areas to merge the projection areas that intersect and / or have too small intervals in the same scanning band; The combined projection areas are used as rare earth element distribution areas in the useful waste, and the rare earth element distribution areas are marked in the three-dimensional model.

[0017] Preferably, step A4 comprises: A401. Obtain the coordinates of the four vertices of each of the rare earth element distribution regions on the three-dimensional model, recorded as vertex coordinates; A402. Determine whether the rare earth element distribution areas are connected according to the vertex coordinates; A403. If there are connected rare earth element distribution areas, the area formed by connecting the connected rare earth element distribution areas is taken as the connected area, and the following is executed: Enveloping the connected area using a plurality of enveloping methods to obtain envelope areas corresponding to the plurality of enveloping methods; Calculating the evaluation value of each of the envelope regions according to an evaluation function related to the perimeter and area of ​​the envelope region; Determine the optimal envelope area of ​​the connected area according to the evaluation value; A404. If there is a connected area, a corresponding optimal envelope area is cut out from the useful waste as one of the items to be refined; A405. If an independent area exists, the independent area is cut out from the useful waste as one of the items to be refined; the independent area is a rare earth element distribution area that is not connected to other rare earth element distribution areas.

[0018] Preferably, the evaluation function is: ; ; ; in, 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, is the total perimeter of the rare earth element distribution area in the connected area, is the area of ​​the connected region, is the area of ​​the envelope.

[0019] Beneficial effects: The waste rare earth recovery method based on the feature marking strategy provided by the present 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 and mark the distribution area of ​​rare earth elements, cutting according to the marked three-dimensional model, retaining the part containing the rare earth element distribution area as the object to be refined, and finally refining the rare earths on the object 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 performs targeted cutting and refining, thereby improving the utilization rate of chemical reaction raw materials, reducing refining costs, and shortening refining time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A flow chart of a waste rare earth recovery method based on a feature marking strategy provided in an embodiment of the present application.

[0021] Figure 2 A schematic diagram of exemplary rare earth element distribution area labeling results.

[0022] Figure 3 This is a schematic diagram of the first connection situation between adjacent rare earth element distribution areas.

[0023] Figure 4 This is a schematic diagram of the second connection situation between adjacent rare earth element distribution areas.

[0024] Figure 5 A schematic diagram of the envelope results of an envelope method.

[0025] Figure 6 A schematic diagram of the envelope results of another envelope method. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0027] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so 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 this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0028] In the field of rare earth recycling, traditional methods have the problem of insufficient characterization and labeling of rare earth distribution in waste, resulting in low utilization rate of chemical reaction raw materials, high refining cost and long time consumption. This application proposes a waste rare earth recycling method based on a characteristic labeling strategy, aiming to solve this technical problem.

[0029] Please refer to Figure 1 , Figure 1 A method for recovering rare earth from waste based on a feature marking strategy in some embodiments of the present application is used to recover rare earth from plate-like waste, comprising the steps of: A1. Use Raman spectroscopy to identify useful waste containing rare earth compounds from recycled waste; A2. Obtain a three-dimensional model of useful waste; A3. Use X-ray fluorescence spectroscopy to determine the distribution area of ​​rare earth elements in useful waste and mark each rare earth element distribution area 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 area as the item to be refined; A5. Refine rare earth elements from the items to be refined.

[0030] The technical solution uses Raman spectroscopy to identify waste containing rare earth compounds, ensuring that only useful waste is processed; obtains a three-dimensional model and uses X-ray fluorescence spectroscopy to determine the distribution area of ​​rare earth elements to ensure accurate positioning of rare earth elements; marks the distribution area of ​​rare earth elements in the three-dimensional model for subsequent cutting; cuts according to the markings, retains the part containing rare earth elements, and reduces unnecessary processing; and refines rare earths from the items to be refined to improve the efficiency of rare earth recovery. Through these steps, the technical solution can efficiently recover rare earth elements from plate-like waste, solving the problem of low utilization rate of chemical reaction raw materials caused by uneven distribution of rare earth elements.

[0031] In practical applications, waste 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, the Raman spectrum data of the recycled waste is obtained by Raman spectroscopy analysis technology, and matched with the standard Raman spectrum data in the reference database to identify useful waste containing rare earth compounds. Then, a laser three-dimensional scanning device is used to scan the useful waste or other methods are used to obtain its three-dimensional model. Next, an X-ray fluorescence spectrometer is used to scan the useful waste layer by layer, obtain the fluorescence spectrum of each scanned layer, and identify the rare earth content and distribution area. After marking these areas in the three-dimensional model, cutting is performed according to the markings, and the part containing rare earth elements is retained for refining. Through these steps, the method of the present application can efficiently recover rare earth elements from plate-like waste, solve the problem of low utilization rate of chemical reaction raw materials caused by uneven distribution of rare earth elements, improve rare earth recovery efficiency, and reduce refining cost and time.

[0032] In some embodiments, step A1 comprises: A101. Obtaining Raman spectrum data of recycled waste, recorded as first Raman spectrum data; A102. Matching the first Raman spectrum data with each standard Raman spectrum data in the first reference database; the first reference database contains quasi-Raman spectrum data corresponding to a variety of rare earth compounds; A103. If the match is successful, the corresponding waste is determined to be useful waste containing rare earth compounds, otherwise the corresponding waste is determined to be useless waste not containing rare earth compounds.

[0033] By obtaining the Raman spectrum data of the recycled waste and matching it with the standard Raman spectrum data in the first reference database, useful waste containing rare earth compounds can be effectively identified, thereby distinguishing useless waste. 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 containing rare earth compounds from recycled waste is solved. Specifically, by obtaining the Raman spectrum data of the waste and matching it with the standard data, it is possible to accurately determine whether the waste contains rare earth compounds, thereby improving the efficiency and accuracy of waste recycling.

[0034] Among them, the existing Raman spectroscopy analysis equipment can be used to perform a "lattice" scan (i.e., a 3*3 or 4*4 dot matrix) on the recycled waste to obtain the first Raman spectrum data.

[0035] Raman spectroscopy is a non-destructive testing technology based on the light scattering effect, which can provide molecular vibration information of substances. The first Raman spectrum data is obtained by measuring the Raman spectrum of the recycled waste. The standard Raman spectrum data in the first reference database are pre-stored standard Raman spectrum data of a variety of rare earth compounds, which are obtained by measuring the Raman spectrum of known rare earth compounds. The matching process is to compare the first Raman spectrum data with the standard Raman spectrum data in the first reference database to determine the degree of similarity between them. If the match is successful, it means that the waste contains rare earth compounds; if the match fails, it means that the waste does not contain rare earth compounds.

[0036] Specifically, the matching process can use a variety of spectral matching algorithms, such as the least squares method, the correlation coefficient method, the principal component analysis method, etc. These algorithms can effectively compare the similarity of the spectral data, so as to determine whether the waste contains rare earth compounds. In addition, the standard Raman spectral data in the first reference database can be classified and stored according to different rare earth compounds to improve the efficiency and accuracy of the matching process.

[0037] The present application utilizes Raman spectroscopy analysis technology and spectral matching algorithms to accurately determine whether waste contains rare earth compounds. By accurately identifying useful waste containing rare earth compounds, these wastes can be recycled and processed first, thereby improving the utilization rate of rare earth resources and avoiding unnecessary processing of useless waste, thereby reducing the cost in the recycling process.

[0038] In fact, the recycled waste can be classified in advance, and the same type of waste can be classified into one category, that is, before step A1, it also includes: A0. Classify the recycled waste and classify the same type of waste into one category. Therefore, in step A1, several samples can be extracted for each type of waste for Raman spectroscopy analysis, and finally determine whether each type of waste is useful waste based on the analysis results of each sample; for example, for the same type of waste, if the number of samples determined to be useful waste accounts for more than a preset ratio threshold (which can be set according to actual needs) in the total number of samples of this type of waste, then the type of waste is finally determined to be useful waste, otherwise, the type of waste is finally determined to be useless waste. In this way, the workload of Raman spectroscopy analysis can be reduced and the recycling efficiency can be improved.

[0039] Among them, in step A2, a variety of methods can be used to obtain the three-dimensional model of useful waste.

[0040] For example, in some embodiments, step A2 includes: Use laser 3D scanning equipment to scan useful waste and obtain the corresponding 3D model.

[0041] Laser 3D scanning equipment can capture the surface details of an object with high precision and generate a detailed 3D model by emitting laser beams and receiving reflected signals. The high scanning accuracy of this equipment can ensure that the generated 3D 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, different wavelengths of lasers can be used, and the scanning speed and resolution can be adjusted to meet the scanning requirements of different types of waste. For example, for waste with more complex surfaces, high-resolution mode can be selected for scanning to ensure that all details are captured.

[0042] By using laser 3D scanning equipment to scan useful waste, its 3D model can be quickly and accurately obtained without destroying the waste. Compared with traditional manual measurement methods, laser 3D scanning equipment has higher accuracy and efficiency, and can greatly reduce measurement errors and time costs. Therefore, it provides reliable basic data for subsequent rare earth element distribution area marking and cutting, ensuring the efficiency and accuracy of the rare earth recovery process.

[0043] Among them, each useful waste can be scanned to generate a corresponding three-dimensional model; however, in order to reduce the total time spent on establishing the three-dimensional model, a sample can be extracted from each type of useful waste and scanned to generate a three-dimensional model as a general three-dimensional model of the corresponding type of useful waste.

[0044] For another example, in some embodiments, step A2 includes: According to the category of useful waste, the corresponding three-dimensional model is extracted from the three-dimensional model library; the three-dimensional model library stores pre-established three-dimensional models of various types of waste.

[0045] Through this solution, 3D models matching useful waste categories can be quickly and accurately obtained from the 3D model library, thereby improving the efficiency and accuracy of the rare earth recycling process.

[0046] During the implementation process, a multi-level 3D model library can be established to classify, store and manage different types of waste. For example, waste can be divided into different categories such as electronic waste and industrial waste, and a corresponding 3D model can be established for each category. In actual application, the system will automatically extract the corresponding 3D model from the model library according to the input waste category. In addition, the construction and maintenance of the model library can be continuously optimized in combination with machine learning algorithms to improve the accuracy and practicality of the model.

[0047] This application can effectively solve the problem of resource waste caused by uneven distribution of rare earth elements in the prior art by introducing the extraction technology of the three-dimensional model library. 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 recycling, and reduces the cost.

[0048] Preferably, step A3 comprises: A301. Scan the useful waste layer by layer using an X-ray fluorescence spectrometer 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; A302. Identify the rare earth content at each position of each scanning layer according to the fluorescence spectrum to be identified; A303. Compare the identified rare earth content with the preset content threshold to determine the rare earth enriched area in each scanning layer; A304. Determine the distribution area of ​​rare earth elements in useful waste based on the distribution position of each rare earth enrichment area, and mark each rare earth element distribution area in the three-dimensional model.

[0049] By scanning the waste layer by layer using an X-ray fluorescence spectrometer, the fluorescence spectrum of each scanning layer can be obtained. By analyzing these fluorescence spectrum lines, the rare earth content at each position of each scanning layer can be identified. By comparing with the preset content threshold, the location of the rare earth enriched area can be determined. According to the location of these rare earth enriched areas, the distribution area of ​​rare earth elements is marked in the three-dimensional model. The function of this technical feature is to accurately identify and mark the distribution area of ​​rare earth elements by scanning and analyzing the fluorescence spectrum layer by layer. Through the above scheme, the technical problem of how to accurately identify and mark the distribution area 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.

[0050] In step A301, each scanning layer is scanned using an X-ray beam of equal width to form a plurality of parallel scanning bands on each scanning layer, with adjacent scanning bands connected at one side; during the scanning process, the fluorescence spectrum line at the scanning position is recorded as the fluorescence spectrum line to be identified.

[0051] For example Figure 2 In the embodiment, each strip region f is a scanning band, wherein 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 may be moved along a serpentine moving path to improve scanning continuity, thereby improving scanning efficiency, but is not limited thereto.

[0052] This scanning method can ensure that each scanning layer can be fully covered during the scanning process, and the fluorescence spectrum of each position can be accurately recorded, so as to effectively identify the distribution area of ​​rare earth elements. This scanning method can solve the problem of how to effectively record and identify the distribution area of ​​rare earth elements during the scanning process. Among them, some existing X-ray fluorescence spectrometers have a layer-by-layer scanning mode, and layer-by-layer scanning (i.e. "slice" scanning) can be achieved by starting the layer-by-layer scanning program. The layer-by-layer scanning method peels off the material on the surface of the sample layer by layer and detects the elemental composition in each layer layer by layer. This method can ensure that even if the rare earth elements are unevenly distributed in the sample, they can still be accurately detected.

[0053] In the process of scanning, the X-ray fluorescence spectrometer can compare the recorded fluorescence spectrum to be identified with the standard fluorescence spectrum of known rare earth elements to determine whether the scanned position contains rare earth elements and the corresponding rare earth content. This is a prior art and will not be described in detail here.

[0054] Preferably, step A303 includes: In each scanning band, a continuous area formed by scanning positions where the identified rare earth content is not less than a content threshold (which can be set according to actual needs) is taken as a rare earth enriched area.

[0055] For example, in a scanning band, according to the scanning sequence, the rare earth contents of each scanning position obtained are h1, h2, ..., hn, n is the number of scanning positions in the scanning band, and assuming that h1 to h30, and h50 to h90 are not less than the content threshold, then the rectangular area from the scanning position of h1 to the scanning position of h30 in the scanning band is taken as a rare earth-enriched area, and the rectangular area from the scanning position of h50 to the scanning position of h90 in the scanning band is taken as another rare earth-enriched area.

[0056] Sometimes, the spacing between adjacent rare earth-enriched areas in the same scanning band is small (if the spacing is less than a preset spacing threshold, it is considered to be small, and the preset spacing threshold can be set according to actual needs). In this case, the corresponding rare earth-enriched areas and the areas between these rare earth-enriched areas can be merged into one rare earth-enriched area to reduce the number of rare earth-enriched areas and reduce the amount of calculation in subsequent steps.

[0057] Among them, A304 includes: Project each rare earth-enriched area along the normal direction (i.e., the thickness direction of the useful waste) onto the surface of the useful waste to obtain the corresponding projection area; Merging the projection areas to merge the projection areas that intersect and / or have too small intervals in the same scanning band; The combined projection areas are used as rare earth element distribution areas in useful wastes, and each rare earth element distribution area is marked in the three-dimensional model.

[0058] Through the above technical means, the problem of merging the rare earth element distribution area during projection can be effectively solved, so that the rare earth element distribution area can be accurately marked in the three-dimensional model, thereby improving the efficiency and accuracy of rare earth recovery.

[0059] Projection algorithms can be used to project each rare earth-enriched area onto the surface of the useful waste along the normal direction. These algorithms can obtain the corresponding projection area by calculating the projection position of each rare earth-enriched area in the normal direction. For the merging of projection areas, image processing techniques, such as region merging algorithms, can be used to merge projection areas that intersect and / or have too small intervals. Mark the merged projection areas (including the merged projection areas and the original projection areas that have not been merged with other projection areas. For example, before the merging process, the projection areas corresponding to a scanning band include areas 1, 2, 3, and 4. During the merging process, areas 1 and 2 are merged into area 5. Then, the merged projection areas include areas 3, 4, and 5). Different colors or marking symbols can be used to mark them in the three-dimensional model (such as Figure 2Different colors are used to mark the distribution areas of each rare earth element (the filled area in the figure is the rare earth element distribution area) to facilitate subsequent identification and processing.

[0060] Among them, intersecting projection areas refer to projection areas that at least partially overlap (including the case where one side shares a common edge), and projection areas with too small intervals refer to projection areas whose intervals are less than a preset interval threshold (which can be set according to actual needs).

[0061] Since each rare earth enrichment area is a rectangular area, each rare earth element distribution area is also a rectangular area, such as Figure 2 shown.

[0062] Specifically, step A4 includes: A401. Obtain the coordinates of the four vertices of each rare earth element distribution region on the three-dimensional model, recorded as vertex coordinates; A402. Determine whether the rare earth element distribution areas are connected according to the vertex coordinates; A403. If there are connected rare earth element distribution areas, the area formed by connecting the connected rare earth element distribution areas is taken as the connected area, and the following is executed: Using multiple enveloping methods to envelop the connected area, and obtaining the envelope areas corresponding to the multiple enveloping methods; Calculate the evaluation value of each envelope area according to the evaluation function related to the perimeter and area of ​​the envelope area; Determine the optimal envelope area of ​​the connected area according to the evaluation value; A404. If there is a connected area, cut out the corresponding optimal envelope area from the useful waste as one of the items to be refined; A405. If an independent area exists, the independent area is cut out from the useful waste as one of the items to be refined; the independent area is a rare earth element distribution area that is not connected to other rare earth element distribution areas.

[0063] In fact, if each rare earth element distribution area is cut separately, the overall cutting route will be longer and the cutting time required will be longer; cutting the connected rare earth element distribution areas as a whole can reduce the cutting time and improve the cutting efficiency.

[0064] Among them, in step A402, when the two rare earth element distribution areas satisfy: (corresponding to Figure 3 or (corresponding to Figure 4 ), it is determined that the two rare earth element distribution areas are connected; wherein, Figure 3 , Figure 4 middle, , , , represent the upper left vertex, lower left vertex, upper right vertex and lower right vertex of the left rare earth element distribution area in the two rare earth element distribution areas respectively, , , , represent the upper left vertex, lower left vertex, upper right vertex and lower right vertex of the rare earth element distribution area on the right side of the two rare earth element distribution areas, respectively, Vertex The y-axis coordinate of Vertex The y-axis coordinate of Vertex The y-axis coordinate of Vertex The y-axis coordinate of the reference coordinate system xy is parallel to the length direction of the scanning tape ( Figure 2 The x-axis is horizontal and perpendicular to the y-axis ( Figure 2 , with right being positive).

[0065] In step A403, the area formed by connecting the connected rare earth element distribution areas is regarded as a connected area, which means that the area formed by the sequentially connected rare earth element distribution areas is regarded as a connected area. Figure 2 In the figure, the three rare earth element distribution areas on the left are connected, so the area composed of the three rare earth element distribution areas is regarded as a connected area.

[0066] The enveloping method may include: enveloping the connected area with the outer contour line of the connected area. The envelope line at this time is the outer contour line of the connected area, that is, a closed line formed by connecting the non-common parts (non-overlapping parts) of all the edges of the rare earth element distribution areas in the connected area. Since the envelope area refers to the area surrounded by the envelope line, the envelope area when enveloping by this method is the same as the connected area.

[0067] The enveloping method may also include: enveloping the connected area with a minimum circumscribed circle that can enclose the entire connected area (the envelope line in this case is the minimum circumscribed circle), enveloping the connected area with a minimum circumscribed rectangle that can enclose the entire connected area (the envelope line in this case is the minimum circumscribed rectangle, such as Figure 5 The connected area is enclosed by the smallest circumscribed ellipse that can surround the entire connected area (the envelope in this case is the smallest circumscribed ellipse).

[0068] The enveloping method may also include: taking the vertices of all rare earth element distribution areas in the connected area as a point set, and using a convex hull algorithm to determine the minimum convex polygon containing all points in the point set, and enveloping the connected area with the minimum convex polygon (the envelope line in this case is the minimum convex polygon, such as Figure 6 The dotted polygonal box on the left). The convex hull algorithm is an existing technology and will not be described in detail here.

[0069] The enveloping method is not limited thereto. In practical applications, the number and type of the enveloping method can be selected as required.

[0070] Among them, except for the method of enveloping the connected area with the outer contour line of the connected area, the envelope area obtained by other enveloping methods will introduce parts that do not contain rare earth elements, resulting in the subsequent rare earth refining. These extra parts are processed together, which will increase the refining cost and refining time to a certain extent, but it is beneficial to reduce the circumference of the cutting area (i.e., the envelope area), 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 favorable and unfavorable effects and achieve an improvement in comprehensive benefits.

[0071] 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: ; ; ; in, is the evaluation value, is the weight value, and (Specific details can be adjusted 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 region, is the area of ​​the envelope.

[0072] Using the above evaluation function, The larger the better, so select The largest envelope area is the optimal envelope area; it can be adjusted To adjust the envelope perimeter and area to better balance the impact of the two and achieve overall benefit enhancement.

[0073] Among them, the perimeter and area of ​​the envelope area can be calculated according to the specific shape of the envelope area. For example, the perimeter and area of ​​the circular envelope area can be calculated according to the perimeter calculation formula and area formula of the circle, the perimeter and area of ​​the elliptical envelope area can be calculated according to the perimeter calculation formula and area formula of the ellipse, and the perimeter and area of ​​the polygonal (such as a rectangle, the outer contour of a connected area, a convex polygon, etc.) envelope area can be calculated according to the coordinates of each vertex of the polygon combined with the geometric relationship.

[0074] in, and It can be calculated according to the following formula: ; ; Wherein, 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 ith rare earth element distribution area, The y-axis coordinate of the lower edge of the i-th rare earth element distribution area, thus, is the length of the i-th rare earth element distribution region.

[0075] When cutting, it is necessary to cut out the optimal envelope area and the independent rare earth element distribution area (i.e., the independent area) as the object to be refined. Figure 2 In the figure, the two rare earth element distribution areas on the right are not connected to other rare earth element distribution areas, so the two rare earth element distribution areas on the right are independent areas, and the three rare earth element distribution areas on the left form a connected area. Figure 2 In this case, it is necessary to cut out an optimal envelope area and two independent areas as the items to be refined.

[0076] Specifically, step A5 includes: chemically reacting the cut object to be refined with 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 prior art and will not be described in detail here.

[0077] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0078] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. 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 earth from waste based on a feature marking strategy, for recovering rare earth from plate-like waste, characterized in that: Includes steps: A1. Use Raman spectroscopy to identify useful waste containing rare earth compounds from recycled waste; A2. Obtaining a three-dimensional model of the useful waste; A3. Determine the distribution area of ​​rare earth elements in the useful waste using X-ray fluorescence spectrometry technology, and mark each rare earth element distribution area in the three-dimensional model; A4. Cutting the useful waste according to the marked three-dimensional model to retain the portion containing the rare earth element distribution area as the item to be refined; A5. Refining rare earths from the object to be refined.

2. The method for recycling waste rare earths based on a feature marking strategy according to claim 1, characterized in that: Step A1 includes: Obtaining Raman spectrum data of the recycled waste, recorded as first Raman spectrum data; Matching the first Raman spectrum data with each standard Raman spectrum data in a first reference database; the first reference database contains quasi-Raman spectrum data corresponding to a plurality of rare earth compounds; If the match is successful, the corresponding waste is determined to be useful waste containing rare earth compounds, otherwise the corresponding waste is determined to be useless waste not containing rare earth compounds.

3. The waste rare earth recovery method based on the feature marking strategy according to claim 1 is characterized in that: Step A2 includes: The useful waste is scanned by a laser three-dimensional scanning device to obtain a corresponding three-dimensional model.

4. The method for recycling waste rare earths based on a feature marking strategy according to claim 1, characterized in that: Step A2 includes: According to the categories of the useful waste, the corresponding three-dimensional model is extracted from a three-dimensional model library; the three-dimensional model library stores pre-established three-dimensional models of various types of waste.

5. The method for recycling waste rare earths based on a feature marking strategy according to claim 1, characterized in that: Step A3 includes: A301. Scan the useful waste layer by layer using an X-ray fluorescence spectrometer 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; A302. Identify the rare earth content of each position of each scanning layer according to the fluorescence spectrum to be identified; A303. Compare the identified rare earth content and the preset content threshold to determine the rare earth-enriched area in each of the scanned layers; A304. Determine the distribution area of ​​rare earth elements in the useful waste according to the distribution position of each rare earth enrichment area, and mark each rare earth element distribution area in the three-dimensional model.

6. The method for recycling waste rare earths based on a feature marking strategy according to claim 5, characterized in that: In step A301, each scanning layer is scanned using an X-ray beam of equal width to form a plurality of parallel scanning bands on each scanning layer, with adjacent scanning bands connected at one side; during the scanning process, the fluorescence spectrum line at the scanning position is recorded as the fluorescence spectrum line to be identified.

7. The waste rare earth recovery method based on the feature marking strategy according to claim 6 is characterized in that: Step A303 includes: In each of the scanning bands, a continuous area formed by scanning positions where the identified rare earth content is not less than the content threshold is taken as a rare earth enriched area.

8. The method for recycling waste rare earths based on a feature marking strategy according to claim 6, characterized in that: A304 includes: Projecting each of the rare earth-enriched areas along the normal direction onto the surface of the useful waste to obtain a corresponding projection area; Merging the projection areas to merge the projection areas that intersect and / or have too small intervals in the same scanning band; The combined projection areas are used as rare earth element distribution areas in the useful waste, and the rare earth element distribution areas are marked in the three-dimensional model.

9. The method for recycling waste rare earths based on a feature marking strategy according to claim 5, 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, recorded as vertex coordinates; A402. Determine whether the rare earth element distribution areas are connected according to the vertex coordinates; A403. If there are connected rare earth element distribution areas, the area formed by connecting the connected rare earth element distribution areas is taken as the connected area, and the following is executed: Enveloping the connected area using a plurality of enveloping methods to obtain envelope areas corresponding to the plurality of enveloping methods; Calculating the evaluation value of each of the envelope regions according to an evaluation function related to the perimeter and area of ​​the envelope region; Determine the optimal envelope area of ​​the connected area according to the evaluation value; A404. If there is a connected area, a corresponding optimal envelope area is cut out from the useful waste as one of the items to be refined; A405. If an independent area exists, the independent area is cut out from the useful waste as one of the items to be refined; the independent area is a rare earth element distribution area that is not connected to other rare earth element distribution areas.

10. The method for recycling waste rare earths based on a feature marking strategy according to claim 9, characterized in that: The evaluation function is: ； ； ； in, 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, is the total perimeter of the rare earth element distribution area in the connected area, is the area of ​​the connected region, is the area of ​​the envelope.

Images