Coal on-line sorting precision monitoring and analyzing system and method

Abstract

The invention provides a coal online separation precision monitoring and analyzing system and method. The method comprises the following steps: adding magnetic small balls with different particle sizes during separation of a cyclone, recovering the magnetic small balls from separated products, measuring the mixing amount of the different magnetic small balls in clean coal and gangue, weighing to obtain real-time product yield, and adopting an improved suspension distribution model to obtain the real-time product yield. The distribution curve of the product is predicted on line, the coal sorting precision is reflected in real time, the sorting process is optimized, and the coal sorting precision and efficiency are improved. And meanwhile, the automation level in the coal washing process of an enterprise can be remarkably improved, the labor cost and the operation cost are reduced, and therefore remarkable economic benefits are brought to the enterprise.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal sorting, and in particular relates to a system and method for monitoring and analyzing the accuracy of online coal sorting. Background Art

[0002] As an important energy resource, coal sorting process plays a key role in coal product quality and economic benefits. Different sorting systems and sorting processes have different effects on coal sorting, resulting in different clean coal yields. Therefore, in order to improve the yield of clean coal, it is necessary to evaluate the sorting effects of different sorting processes.

[0003] At the same time, the traditional coal sorting process mainly relies on manual operation, which often leads to unstable quality and output of sorted clean coal products. Therefore, real-time monitoring of the coal sorting effect is required.

[0004] However, the current evaluation and monitoring of coal sorting effects mainly rely on experience and judgment, which is affected by personal subjective factors and has low accuracy. Summary of the invention

[0005] In order to solve the above-mentioned problems of the prior art, the present invention provides a coal online sorting accuracy monitoring and analysis system and method, which can monitor the coal sorting accuracy in real time, timely feedback production parameters, optimize the sorting process, and improve the coal sorting accuracy and efficiency.

[0006] The present invention is achieved through the following technical solutions: The present invention provides a coal online sorting accuracy monitoring and analysis system, comprising: The cyclone is used to separate the raw coal and the magnetic balls; the magnetic balls are balls of different densities and different particle sizes, and the same particle size corresponds to the same density; Curved screen, used to remove the overflow from the cyclone; The first linear vibrating screen is used to remove the material on the curved screen; A first magnetic separation component is used to perform magnetic separation on the screen material of the first linear vibrating screen to separate low-density magnetic beads; A clean coal bin, used for collecting the clean coal separated by the first magnetic separation assembly; The second linear vibrating screen is used to remove the medium from the underflow of the cyclone; A second magnetic separation component is used to perform magnetic separation on the screen material of the second linear vibrating screen to separate high-density magnetic beads; A gangue bin, used for collecting the gangue separated by the second magnetic separation assembly; The laminated screen is used to grade and screen the low-density magnetic beads and the high-density magnetic beads separated by the first magnetic separation component and the second magnetic separation component; Weighing equipment, used to weigh the low-density magnetic balls and high-density magnetic balls of various particle sizes screened by the laminated screen; The controller is used to predict the distribution curve of clean coal according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade.

[0007] Preferably, the first magnetic separation component includes a first magnetic separator and a clean coal belt, and the first magnetic separator is located above the clean coal belt; the screen material of the first linear vibrating screen is transported to the clean coal bin through the clean coal belt, and the magnetic balls in the screen material of the first linear vibrating screen are recovered to the first magnetic separator during the transportation process.

[0008] Preferably, the second magnetic separation component includes a second magnetic separator and a gangue belt, and the second magnetic separator is located above the gangue belt; the screened material of the second linear vibrating screen is transported to the gangue bin via the gangue belt, and during the transportation process, the magnetic balls in the screened material of the second linear vibrating screen are recovered to the second magnetic separator.

[0009] Preferably, it also includes a combined medium barrel, which is used to collect heavy media that escape from the curved screen, the first linear vibrating screen and the second linear vibrating screen.

[0010] Furthermore, it also includes a slurry pump, and the heavy medium in the combined medium barrel is returned to the cyclone via the slurry pump.

[0011] Preferably, a plurality of magnetic ball barrels are also included, which are respectively used to receive magnetic balls of different densities separated by the laminated screen.

[0012] Preferably, the curved screen is a YHS overflow curved screen.

[0013] Preferably, the laminated screen is a pull-out laminated screen.

[0014] The present invention also provides a method for monitoring and analyzing the accuracy of online coal sorting, based on the above-mentioned system for monitoring and analyzing the accuracy of online coal sorting, comprising: The heavy medium, raw coal and magnetic balls are mixed and added into a cyclone for separation to obtain overflow and underflow; the magnetic balls are balls of different densities and different particle sizes, and the same particle size corresponds to the same density; The overflow carries part of the magnetic balls through the curved screen for primary dehydration and de-mediuming, and the screened material of the curved screen is fed into the first linear vibrating screen for secondary dehydration and de-mediuming; the screened material of the first linear vibrating screen is recycled by the first magnetic separation component, and the remaining clean coal after recycling enters the clean coal bin; the recycled low-density magnetic balls are fed into the laminated screen for graded screening, and the low-density magnetic balls of each particle size grade screened out are weighed to obtain the mass of the low-density magnetic balls of each particle size grade; The underflow carries another part of the magnetic balls through the second linear vibrating screen for dehydration and de-mediuming. The screened material of the second linear vibrating screen is recycled by the second magnetic separation component. The remaining gangue after recycling enters the gangue bin. The recovered high-density magnetic balls are fed into the laminated screen for graded screening. The high-density magnetic balls of each particle size grade screened out are weighed to obtain the mass of the high-density magnetic balls of each particle size grade. The distribution curve of clean coal is predicted according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade.

[0015] Preferably, the distribution curve of clean coal is predicted based on the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade, specifically: the proportion of low-density magnetic balls of each particle size grade in the total low-density magnetic balls is calculated using the mass of low-density magnetic balls of each particle size grade and the mass of total low-density magnetic balls; the proportion of high-density magnetic balls of each particle size grade in the total high-density magnetic balls is calculated using the mass of high-density magnetic balls of each particle size grade and the mass of total high-density magnetic balls; the distribution rate corresponding to each particle size grade is calculated based on the obtained proportion, and the distribution curve is drawn to judge the sorting accuracy.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention adds magnetic beads of different particle sizes during cyclone sorting, recovers the magnetic beads from the sorted product, measures the amount of different magnetic beads mixed in clean coal and gangue, weighs to obtain real-time product yield, adopts an improved suspension distribution model, predicts the distribution curve of the product online, reflects the accuracy of coal sorting in real time, optimizes the sorting process, and improves the accuracy and efficiency of coal sorting. At the same time, it can also significantly improve the automation level of the enterprise's coal washing process, reduce labor costs and operating costs, and thus bring significant economic benefits to the enterprise.

[0017] Furthermore, the present invention is provided with a medium collecting barrel for collecting heavy medium released from the arc screen, the first linear vibrating screen and the second linear vibrating screen, so as to recycle the heavy medium and improve the utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural diagram of the device of the present invention.

[0020] In the figure: cyclone 1, curved screen 2, first linear vibrating screen 3, second linear vibrating screen 4, first magnetic separator 5, second magnetic separator 6, clean coal belt 7, gangue belt 8, laminated screen 9, combined medium barrel 10, first magnetic ball barrel 11, second magnetic ball barrel 12, gangue bin 13, clean coal bin 14, slurry pump 15. DETAILED DESCRIPTION

[0021] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0022] It should be noted that the process equipment or devices not specifically specified in the following embodiments are all conventional equipment or devices in the art.

[0023] It should be noted that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to define the scope of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the present invention without substantially changing the technical content.

[0024] In addition, it should be noted that the terms "first", "second", etc. of the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. The orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention; in addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements.

[0025] The coal online sorting accuracy monitoring and analysis system of the present invention comprises: The cyclone 1 is used to separate the raw coal and the magnetic balls; the magnetic balls are balls of different densities and different particle sizes, and the same particle size corresponds to the same density; The curved screen 2 is used to remove the overflow of the cyclone 1; The first linear vibrating screen 3 is used to remove the material on the curved screen 2; The first magnetic separation component is used to perform magnetic separation on the screen material of the first linear vibrating screen 3 to separate low-density magnetic beads; A clean coal bin 14, for collecting the clean coal separated by the first magnetic separation assembly; The second linear vibrating screen 4 is used to remove the medium from the bottom flow of the cyclone 1; A second magnetic separation component is used to magnetically separate the material on the second linear vibrating screen 4 to separate high-density magnetic beads; Gangue bin 13, used for collecting the gangue separated by the second magnetic separation assembly; The laminated screen 9 is used to grade and screen the low-density magnetic beads and the high-density magnetic beads separated by the first magnetic separation component and the second magnetic separation component; A weighing device is used to weigh the low-density magnetic balls and high-density magnetic balls of each particle size grade screened by the laminated screen 9; The controller is used to predict the distribution curve of clean coal according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade.

[0026] Specifically, in some embodiments, the first magnetic separation component includes a first magnetic separator 5 and a clean coal belt 7, and the first magnetic separator 5 is located above the clean coal belt 7; the screened material of the first linear vibrating screen 3 is transported to the clean coal bin 14 through the clean coal belt 7, and the magnetic beads in the screened material of the first linear vibrating screen 3 are recovered to the first magnetic separator 5 during the transportation process. The second magnetic separation component includes a second magnetic separator 6 and a gangue belt 8, and the second magnetic separator 6 is located above the gangue belt 8; the screened material of the second linear vibrating screen 4 is transported to the gangue bin 13 through the gangue belt 8, and the magnetic beads in the screened material of the second linear vibrating screen 4 are recovered to the second magnetic separator 6 during the transportation process. The function of each magnetic separation component of the present invention is to separate the magnetic beads, and the magnetic separation component can be replaced by other forms, as long as the separation and recovery of the magnetic beads can be achieved.

[0027] In order to recover the heavy medium, the present invention further provides a combined medium barrel 10, which is used to collect the heavy medium that escapes from the curved screen 2, the first linear vibrating screen 3, and the second linear vibrating screen 4. The recovered heavy medium can be returned to the cyclone 1 for recycling. Specifically, a slurry pump 15 can be used to return the recovered heavy medium to the cyclone 1.

[0028] In a specific embodiment of the present invention, the curved screen 4 is a YHS overflow curved screen, for example, the model is YHS-1, the screen machine inclination angle is 45°, and the screen slot width is 0.1 mm.

[0029] In a specific embodiment of the present invention, the linear vibrating screen is of model DZSF-520, and the screen hole size is 0.074 mm.

[0030] In a specific embodiment of the present invention, the laminated screen 9 is a pull-out laminated screen, and the screen mesh can be replaced.

[0031] The coal online sorting accuracy monitoring and analysis method of the present invention comprises: The heavy medium, raw coal and magnetic beads are mixed and added into the cyclone 1 for sorting to obtain overflow and underflow; the magnetic beads are beads of different densities and different particle sizes, and the same particle size corresponds to the same density; The overflow carries part of the magnetic balls through the curved screen 2 for primary dehydration and de-mediuming, and the screened material of the curved screen 2 is fed into the first linear vibrating screen 3 for secondary dehydration and de-mediuming; the screened material of the first linear vibrating screen 3 is passed through the first magnetic separation component to recover the magnetic balls, and the remaining clean coal after recovery enters the clean coal bin 14; the recovered low-density magnetic balls are fed into the laminated screen 9 for graded screening, and the low-density magnetic balls of each particle size grade screened out are weighed to obtain the mass of the low-density magnetic balls of each particle size grade; The underflow carries another part of the magnetic balls through the second linear vibrating screen 4 for dehydration and de-mediuming. The screened material of the second linear vibrating screen 4 is recovered by the second magnetic separation component. The remaining gangue after recovery enters the gangue bin 13. The recovered high-density magnetic balls are fed into the laminated screen 9 for graded screening. The high-density magnetic balls of each particle size grade screened are weighed to obtain the mass of the high-density magnetic balls of each particle size grade. The distribution curve of clean coal is predicted according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade.

[0032] The magnetic beads described in the present invention are beads with different densities and different particle sizes, and the same particle size corresponds to the same density.

[0033] In a specific embodiment of the present invention, the density of the magnetic balls includes the following: 1.25 kg / cm 3 , 1.30kg / cm 3 , 1.34 kg / cm 3 , 1.37 kg / cm 3 , 1.40 kg / cm 3 , 1.45 kg / cm 3 , 1.50 kg / cm3 , 1.70 kg / cm 3 , 1.80 kg / cm 3 , 1.90 kg / cm 3 The particle sizes corresponding to the above densities are 55 mm, 50 mm, 45 mm, 40 mm, 35 mm, 30 mm, 25 mm, 20 mm, 15 mm, and 10 mm respectively.

[0034] The particle size and density of the magnetic balls of the present invention can be changed according to the particle size and density composition of the actual raw coal, so as to better reflect the product sorting effect in actual production.

[0035] The method for predicting the distribution curve of clean coal according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade is specifically as follows: the mass of low-density magnetic balls of each particle size grade and the mass of total low-density magnetic balls are used to calculate the proportion of low-density magnetic balls of each particle size grade in the total low-density magnetic balls; the mass of high-density magnetic balls of each particle size grade and the mass of total high-density magnetic balls are used to calculate the proportion of high-density magnetic balls of each particle size grade in the total high-density magnetic balls; the distribution rate corresponding to each particle size grade is calculated according to the obtained proportion, and the distribution curve is drawn to judge the sorting accuracy.

[0036] Example In this embodiment, the coal online sorting accuracy monitoring and analysis system includes: a cyclone 1, a curved screen 2, a first linear vibrating screen 3, a second linear vibrating screen 4, a first magnetic separator 5, a second magnetic separator 6, a clean coal belt 7, a gangue belt 8, a laminated screen 9, a combined medium barrel 10, a gangue bin 13, a clean coal bin 14, a slurry pump 15 and a plurality of magnetic ball barrels. Figure 1 Only two magnetic ball barrels are shown: a first magnetic ball barrel 11 and a second magnetic ball barrel 12, and other magnetic ball barrels are not shown. The cyclone 1 is a heavy medium cyclone.

[0037] Based on the coal online sorting accuracy monitoring and analysis system, the method for coal online sorting accuracy monitoring and analysis includes the following steps: The raw coal and heavy medium are mixed in a stirring barrel and then mixed with magnetic balls to form a slurry, which is then added to the cyclone 1 for separation. At this time, the density in the cyclone 1 is 1.40 g / cm 3 After sorting, overflow and underflow are obtained. The density of magnetic beads includes the following: 1.25 kg / cm 3 , 1.30 kg / cm 3 , 1.34 kg / cm 3 , 1.37 kg / cm 3 , 1.40 kg / cm 3 , 1.45 kg / cm3 , 1.50 kg / cm 3 , 1.70 kg / cm 3 , 1.80 kg / cm 3 , 1.90 kg / cm 3 The particle sizes corresponding to the above densities are 55 mm, 50 mm, 45 mm, 40 mm, 35 mm, 30 mm, 25 mm, 20 mm, 15 mm, and 10 mm respectively.

[0038] The overflow of the cyclone 1 is a low-density product, which is fed into a curved screen 2 with an inclination angle of 45° and Φ0.1 mm for primary dehydration and media removal; in order to further remove the heavy medium on the product, the screened material of the curved screen 2 is fed into a first linear vibrating screen 3 with a diameter of Φ0.074 mm for secondary dehydration and media removal; the screened material of the curved screen 2 and the screened material of the first linear vibrating screen 3 are heavy media, which enter the combined media barrel 10 for recycling; the screened material of the first linear vibrating screen 3 is passed through a clean coal belt 7 with a first magnetic separator 5 above to recover the magnetic balls, and the remaining clean coal is transported to the clean coal bin 14 by the clean coal belt 7; the magnetic balls recovered by the first magnetic separator 5 are graded and screened by a laminated screen 9 with sieve holes of 55 mm, 50 mm, 45 mm, 40 mm, 35 mm, 30 mm, 25 mm, 20 mm, 15 mm, and 10 mm, and the low-density magnetic balls are sorted out and weighed.

[0039] The bottom flow of the cyclone 1 is a high-density product. Due to the high density, the arc screen will be severely worn, so it is only dehydrated and de-mediumed through the second linear vibrating screen of Φ0.074 mm. The undersize of the second linear vibrating screen 4 enters the combined medium barrel 10 for recycling; the oversize of the second linear vibrating screen 4 passes through the gangue belt 8 with the second magnetic separator 6 above to recover the magnetic balls, and the remaining gangue enters the gangue bin 13. The magnetic balls recovered by the second magnetic separator 6 are graded and screened through the laminated screen 9 with sieve holes of 55 mm, 50 mm, 45 mm, 40 mm, 35 mm, 30 mm, 25 mm, 20 mm, 15 mm, and 10 mm, respectively, and the high-density magnetic balls are sorted out and weighed.

[0040] The heavy medium in the combined medium barrel 10 is pumped into the cyclone 1 through the slurry pump 15 for recycling.

[0041] After measuring the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade, the proportion of low-density magnetic balls of each particle size grade in the total low-density magnetic balls is calculated using the mass of low-density magnetic balls of each particle size grade and the total mass of low-density magnetic balls; the proportion of high-density magnetic balls of each particle size grade in the total high-density magnetic balls is calculated using the mass of high-density magnetic balls of each particle size grade and the total mass of high-density magnetic balls; the distribution rate corresponding to each particle size grade is calculated based on the obtained proportion, and the distribution curve is drawn to judge the sorting accuracy.

[0042] In addition, the clean coal distribution curve can be predicted according to the mass of low-density magnetic beads and high-density magnetic beads of each particle size grade through a suitable suspension distribution model (RSM-VOF model or RSM-Mixture model), thereby providing method support for determining the optimal sorting density corresponding to a given ash product.

[0043] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A coal online sorting accuracy monitoring and analysis system, characterized in that: include: The cyclone (1) is used to separate raw coal and magnetic balls; the magnetic balls are balls of different densities and different particle sizes, and the same particle size corresponds to the same density; The curved screen (2) is used to remove the overflow of the cyclone (1); A first linear vibrating screen (3) is used to remove the material on the screen of the curved screen (2); A first magnetic separation component, used for magnetically separating the material on the first linear vibrating screen (3) to separate low-density magnetic beads; A clean coal bin (14), used for collecting the clean coal separated by the first magnetic separation assembly; A second linear vibrating screen (4) is used to remove medium from the bottom flow of the cyclone (1); A second magnetic separation component is used to perform magnetic separation on the screen material of the second linear vibrating screen (4) to separate high-density magnetic beads; A gangue bin (13) for collecting the gangue separated by the second magnetic separation component; A laminated screen (9) is used to grade and screen the low-density magnetic beads and the high-density magnetic beads separated by the first magnetic separation component and the second magnetic separation component; A weighing device for weighing the low-density magnetic balls and high-density magnetic balls of various particle sizes screened by the laminated screen (9); The controller is used to predict the distribution curve of clean coal according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade.

2. The coal online sorting accuracy monitoring and analysis system according to claim 1 is characterized in that: The first magnetic separation component comprises a first magnetic separator (5) and a clean coal belt (7), wherein the first magnetic separator (5) is located above the clean coal belt (7); the screen material of the first linear vibrating screen is transported to the clean coal bin (14) via the clean coal belt (7), and during the transport process, the magnetic beads in the screen material of the first linear vibrating screen are recovered into the first magnetic separator (5).

3. The coal online sorting accuracy monitoring and analysis system according to claim 1 is characterized in that: The second magnetic separation component comprises a second magnetic separator (6) and a gangue belt (8), wherein the second magnetic separator (6) is located above the gangue belt (8); the screened material of the second linear vibrating screen is transported to the gangue bin (13) via the gangue belt (8), and during the transport process, the magnetic beads in the screened material of the second linear vibrating screen are recovered into the second magnetic separator (6).

4. The coal online sorting accuracy monitoring and analysis system according to claim 1 is characterized in that: It also comprises a combined medium barrel (10), wherein the combined medium barrel (10) is used to collect heavy medium escaped from the curved screen (2), the first linear vibrating screen (3) and the second linear vibrating screen (4).

5. The coal online sorting accuracy monitoring and analysis system according to claim 4 is characterized in that: It also comprises a slurry pump (15), through which the heavy medium in the combined medium barrel (10) is returned to the cyclone (1).

6. The coal online sorting accuracy monitoring and analysis system according to claim 1 is characterized in that: It also includes a plurality of magnetic ball barrels, which are respectively used to receive magnetic balls of different densities separated by the laminated screen (9).

7. The coal online sorting accuracy monitoring and analysis system according to claim 1 is characterized in that: The curved screen is a YHS overflow curved screen.

8. The coal online sorting accuracy monitoring and analysis system according to claim 1 is characterized in that: The laminated screen (9) is a pull-out type laminated screen.

9. A method for monitoring and analyzing the accuracy of online coal sorting, characterized in that: The coal online sorting accuracy monitoring and analysis system according to any one of claims 1 to 8 comprises: The heavy medium, raw coal and magnetic beads are mixed and added to a cyclone (1) for sorting to obtain overflow and underflow; the magnetic beads are beads of different densities and different particle sizes, and the same particle size corresponds to the same density; The overflow carries part of the magnetic small balls through the curved screen (2) for primary dehydration and de-mediuming, and the screened material of the curved screen (2) is fed into the first linear vibrating screen (3) for secondary dehydration and de-mediuming; the screened material of the first linear vibrating screen (3) is passed through the first magnetic separation component to recover the magnetic small balls, and the remaining clean coal after recovery enters the clean coal bin (14); the recovered low-density magnetic small balls are fed into the laminated screen (9) for graded screening, and the low-density magnetic small balls of each particle size grade screened are weighed to obtain the mass of the low-density magnetic small balls of each particle size grade; The underflow carries another part of the magnetic beads through the second linear vibrating screen (4) for dehydration and de-mediuming. The screened material of the second linear vibrating screen (4) is passed through the second magnetic separation component to recover the magnetic beads. The remaining gangue after recovery enters the gangue bin (13). The recovered high-density magnetic beads are fed into the laminated screen (9) for graded screening. The high-density magnetic beads of each particle size grade screened are weighed to obtain the mass of the high-density magnetic beads of each particle size grade. The distribution curve of clean coal is predicted according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade.

10. The method for monitoring and analyzing the online coal sorting accuracy according to claim 9, characterized in that: The method for predicting the distribution curve of clean coal according to the mass of low-density magnetic balls and high-density magnetic balls of each particle size grade is specifically as follows: the mass of low-density magnetic balls of each particle size grade and the mass of total low-density magnetic balls are used to calculate the proportion of low-density magnetic balls of each particle size grade in the total low-density magnetic balls; the mass of high-density magnetic balls of each particle size grade and the mass of total high-density magnetic balls are used to calculate the proportion of high-density magnetic balls of each particle size grade in the total high-density magnetic balls; the distribution rate corresponding to each particle size grade is calculated according to the obtained proportion, and the distribution curve is drawn to judge the sorting accuracy.

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