A method and system for monitoring overfeeding of a coal preparation plant jig feed

Abstract

The present application relates to the field of material excess monitoring, in particular to an excess monitoring method and system for the feeding of a jigging machine in a coal preparation plant, the excess monitoring method for the feeding of a jigging machine in a coal preparation plant comprising: obtaining a real-time image of a jigging machine to be monitored; obtaining a real-time position of the jigging machine to be monitored by using the real-time image of the jigging machine to be monitored; and obtaining an excess monitoring result of the feeding of the jigging machine to be monitored according to the real-time position of the jigging machine to be monitored.

Description

Technical Field

[0001] This invention relates to the field of material overload monitoring, specifically to a method and system for monitoring overload in the feed of a jigging machine in a coal preparation plant. Background Technology

[0002] In actual production, the jigging chamber of the jig is filled with water and raw coal, forming a bed on the screen plate. During production, the machine is filled with water, and compressed air is periodically fed and discharged through the air valves, creating a pulsating water flow within the jigging chamber. The raw coal, after being moistened by water on the coal feeder, falls into the jig. Under the action of the pulsating and horizontal water flows, the material gradually stratifies according to density and moves towards the discharge end. Adjusting the air volume and the air valve cycle can change the intensity and characteristics of the pulsating water flow, and adjusting the top water flow can also change the strength of the pulsating water flow and the speed of the horizontal water flow. Therefore, the rational allocation of air and water during production is an important means to improve the separation effect. The processing capacity of jigs in general coal preparation plants is between 300t / H and 800t / H (the width of the jigging chamber determines the processing capacity of the jig). Factors affecting the real-time processing capacity of the jig, in addition to the properties and quantity of the raw coal being washed, also include the air volume, water volume, and the frequency and amplitude of the bed pulsation. If the jig processes too much raw coal instantaneously, it will increase the discharge of the gangue section, increasing the load on the gangue bucket elevator (increasing equipment wear and the risk of the bucket elevator being blocked); similarly, it will increase the discharge of the middlings section, increasing the load on the middlings bucket elevator; excessive washing volume will not only make the equipment prone to accidents, but will also cause middlings or gangue to mix into the clean coal, which may result in unstable ash content of the product coal or even quality accidents, seriously affecting the company's profits. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method and system for monitoring excessive feed to a jig in a coal preparation plant. By monitoring the throughput of the bucket elevator below the jig, the system can infer whether the jig's throughput is excessive.

[0004] To achieve the above objectives, the present invention provides a method for monitoring excessive feed to a jig in a coal preparation plant, comprising:

[0005] Acquire real-time images of the jig to be monitored;

[0006] The real-time position of the jig to be monitored is obtained using the real-time image of the jig to be monitored.

[0007] The overfeed monitoring results of the jig under monitoring are obtained based on the real-time location of the jig under monitoring.

[0008] Preferably, acquiring the real-time image of the jig to be monitored includes:

[0009] Real-time monitoring video of the jig to be monitored is obtained using monitoring cameras;

[0010] The real-time monitoring video is used to obtain real-time images of the jig machine to be monitored;

[0011] The resolution of the real-time image of the jig to be monitored is 1920*1080.

[0012] Furthermore, obtaining the real-time position of the jig under monitoring using the real-time image of the jig under monitoring includes:

[0013] The initial processed image of the jig to be monitored is obtained by performing initial processing calculations using the real-time image of the jig to be monitored.

[0014] The real-time position of the jig to be monitored is obtained from the initial processed image of the jig to be monitored.

[0015] Furthermore, the initial processing image of the jig to be monitored is obtained by performing initial processing calculations using the real-time image of the jig to be monitored, including:

[0016] The transmitted light image of the jig under monitoring is obtained by binarizing the central region of the real-time image of the jig under monitoring.

[0017] A morphological closing operation is performed on the transmitted light image of the jig to be monitored to obtain a connected image of the jig region to be monitored.

[0018] The interconnected image of the jigging machine region to be monitored is used as the initial processing image of the jigging machine to be monitored.

[0019] The number of light spots in the transmitted light image of the jig to be monitored is 2.

[0020] Furthermore, obtaining the real-time position of the jig to be monitored based on the initial processed image of the jig to be monitored includes:

[0021] Determine whether the perimeter of the smallest bounding rectangle of the light spot in the initial processed image of the jig to be monitored is within the standard threshold. If so, use the initial processed image of the jig to be monitored as the real-time position of the jig to be monitored; otherwise, abandon the processing.

[0022] The standard threshold ranges from 300px to 400px.

[0023] Preferably, obtaining the overfeed monitoring result of the jig under monitoring based on the real-time position of the jig under monitoring includes:

[0024] When there is a real-time location of the jig to be monitored that corresponds to the initial processed image of the jig to be monitored, the largest circumscribed rectangle of the white area in the connected image of the area of ​​the jig to be monitored corresponding to the initial processed image of the jig to be monitored is obtained as the area to be identified of the jig to be monitored.

[0025] The distance from the bottom edge to the top of the largest circumscribed rectangle in the area to be identified of the jig to be monitored is obtained as the real-time data inside the jig to be monitored;

[0026] Determine whether the real-time data inside the jig to be monitored is greater than the over-limit monitoring threshold. If it is, the over-limit monitoring result of the jig to be monitored is over-limit; otherwise, the over-limit monitoring result of the jig to be monitored is not over-limit.

[0027] The over-detection threshold is 65px.

[0028] A system for monitoring excessive feed to a jigging machine in a coal preparation plant, based on any one of claims 1-6, includes a monitoring camera, a system host, and an industrial network. The monitoring camera is positioned directly in front of the gangue bucket elevator, and the monitoring camera, system host, and industrial network are electrically connected in sequence.

[0029] Preferably, the monitoring camera is positioned directly in front of the gangue bucket elevator and at a relative distance of less than 2m, the monitoring camera is located 1.5m above the ground, the lens of the monitoring camera is tilted upwards at 15°, and the frame rate of the monitoring camera is 25 frames per second.

[0030] Preferably, the system host includes a waterproof and dustproof control box, an image analysis host, a switch, a display device, and an audible and visual alarm device. The image analysis host, the switch, the display device, and the audible and visual alarm device are electrically connected in sequence and are all housed inside the waterproof and dustproof control box.

[0031] Preferably, it also includes explosion-proof supplementary lighting, which is installed above the gangue bucket elevator. The number of explosion-proof supplementary lighting is 2, and the power of the explosion-proof supplementary lighting is 25W.

[0032] Compared with the closest existing technology, the present invention has the following advantages:

[0033] By utilizing video analytics and image recognition technology, the system can directly determine whether the real-time feed rate of the jig exceeds the limit by analyzing the bucket loading status of the bucket elevator through cameras. The overall structure is simple, reducing the need for sensors and avoiding the impact of harsh on-site conditions on traditional monitoring methods, thus improving overall monitoring stability. When the system detects that the bucket elevator is overloaded, it automatically sends an alarm to the coal preparation plant's PLC centralized control system. If necessary, it can intervene in the lower-level machine's interlocking mechanism to stop raw coal feeding immediately, minimizing losses and preventing quality accidents. Attached Figure Description

[0034] Figure 1 This is a flowchart of a method for monitoring excessive feed into a jig in a coal preparation plant, provided by the present invention.

[0035] Figure 2 This is a flowchart illustrating the practical application of an overfeed monitoring method for a jigging machine in a coal preparation plant, provided by the present invention.

[0036] Figure 3 This is a field image of the actual application of the overfeed monitoring method for a jigging machine in a coal preparation plant provided by the present invention;

[0037] Figure 4 This is a schematic diagram of the actual application of the overfeed monitoring method for the jigging machine in a coal preparation plant provided by the present invention.

[0038] Figure 5 This is a schematic diagram of the hopper status of a method for monitoring excessive feed into a jig in a coal preparation plant, provided by the present invention.

[0039] Figure 6 This is a real-time image feature diagram of a method for monitoring excessive feed into a jig in a coal preparation plant, provided by the present invention.

[0040] Figure 7 This is a real-time image of the white area, illustrating a method for monitoring excessive feed into a jig in a coal preparation plant, provided by the present invention.

[0041] Figure 8 This is a schematic diagram of an overfeed monitoring system for a jigging machine in a coal preparation plant, provided by the present invention.

[0042] Figure 9 This is a schematic diagram of the status of a gangue bucket elevator, which is part of an overfeed monitoring system for a jigging machine in a coal preparation plant, provided by the present invention.

[0043] Explanation of reference numerals in the attached figures:

[0044] 1. Gangue bucket elevator; 2. Monitoring camera; 3. Explosion-proof supplementary lighting; 4. System host; 5. Industrial network. Detailed Implementation

[0045] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] Example 1:

[0048] This invention provides a method for monitoring excessive feed into a jig in a coal preparation plant, such as... Figure 1 As shown, it includes:

[0049] S1. Acquire real-time images of the jig to be monitored;

[0050] S2. Obtain the real-time position of the jig to be monitored using the real-time image of the jig to be monitored;

[0051] S3. Obtain the overfeed monitoring result of the jig to be monitored based on the real-time position of the jig to be monitored.

[0052] S1 specifically includes:

[0053] S1-1. Use a monitoring camera to obtain real-time monitoring video of the jig to be monitored;

[0054] S1-2. Obtain real-time images of the jig to be monitored using the real-time monitoring video;

[0055] The resolution of the real-time image of the jig to be monitored is 1920*1080.

[0056] S2 specifically includes:

[0057] S2-1. Initial processing calculations are performed using the real-time image of the jig to be monitored to obtain the initial processed image of the jig to be monitored.

[0058] S2-2. Obtain the real-time position of the jig to be monitored based on the initial processed image of the jig to be monitored.

[0059] S2-1 specifically includes:

[0060] S2-1-1. Binarize the central region of the real-time image of the jig to be monitored to obtain the transmitted light image of the jig to be monitored.

[0061] S2-1-2. Use the transmitted light image of the jig to be monitored to perform morphological closing operation to obtain the connected image of the jig region to be monitored.

[0062] S2-1-3. Use the interconnected image of the jig region to be monitored as the initial processing image of the jig to be monitored;

[0063] The number of light spots in the transmitted light image of the jig to be monitored is 2.

[0064] S2-2 specifically includes:

[0065] S2-2-1. Determine whether the perimeter of the smallest bounding rectangle of the light spot in the initial processing image of the jig to be monitored is within the standard threshold. If so, use the initial processing image of the jig to be monitored as the real-time position of the jig to be monitored. Otherwise, abandon the processing.

[0066] The standard threshold ranges from 300px to 400px.

[0067] S3 specifically includes:

[0068] S3-1. When there is a real-time position of the jig to be monitored that corresponds to the initial processing image of the jig to be monitored, the largest circumscribed rectangle of the white area in the connected image of the jig area corresponding to the initial processing image of the jig to be monitored is obtained as the identification area of ​​the jig to be monitored.

[0069] S3-2. Obtain the distance from the bottom edge to the top of the largest circumscribed rectangle in the area to be identified of the jig to be monitored as the real-time data inside the jig to be monitored;

[0070] S3-3. Determine whether the real-time data inside the jig to be monitored is greater than the over-limit monitoring threshold. If so, the over-limit monitoring result of the jig to be monitored is over-limit; otherwise, the over-limit monitoring result of the jig to be monitored is not over-limit.

[0071] The over-detection threshold is 65px.

[0072] In this embodiment, a method for monitoring excessive feed to a jig in a coal preparation plant is described, such as... Figure 2 As shown, the specific steps for referencing this document are as follows:

[0073] 1. Process the images captured by the camera. When a specific characteristic is found, it indicates that the hopper has moved to the designated position. Based on the results of on-site experiments, this specific characteristic can be marked using the reflective points of the hopper. For example... Figure 3 As shown, the camera's monitoring image size is 1920*1080. When the upper edge of the hopper moves to the middle of the image, the steel plate with water on its surface will reflect the light from the supplementary light above, thus forming two bright spot areas of fixed size in the vertical center of the image.

[0074] 2. Perform "binarization --> morphological opening operation" on the central region of each frame captured by the camera. The resulting image is as follows: Figure 4 As shown. The two reflective bright spots have a minimum bounding rectangle perimeter within the closed interval [300, 400] after processing. This closed interval can be used as a fixed parameter of the program, denoted as [a, b]. It can be concluded that the hopper can be considered to have moved to the specified position when the following two conditions are fully satisfied:

[0075] The algorithm detected two bright spots in the central region of the image, and the minimum circumscribed rectangle of the bright spots has a perimeter of Cleft and Cright.

[0076] And a≤C left≤b, a≤C right≤b;

[0077] 3. For example Figure 5 As shown, when the hopper is not raised to its proper position (i.e., the upper edge of the hopper is below the center of the image), and when the hopper is raised too high (i.e., the upper edge of the hopper exceeds the center of the image), neither of these conditions will result in two bright spots appearing in the camera's image. Figure 6 As shown. This algorithm for monitoring the hopper position can completely replace proximity switches in actual tests, and it is not affected by humid environments, nor does it suffer from the accuracy loss caused by wear and tear on the mechanical mechanism of proximity switches.

[0078] 4. Calculate the height of the gangue material in the hopper. Based on the dimensions of the hopper in the monitoring image, extract the precise shape of the hopper. The dimensions of the hopper are 810px * 280px. Figure 6 In section A), a proximity switch for a mechanical mechanism is installed in the lower left corner of the hopper. To improve accuracy, the hopper image needs to be cropped. The cropped image is shown below. Figure 6 In section B, the hopper needs to remove as much moisture as possible from the gangue during the lifting process; therefore, it is designed to be welded from steel plates with a mesh. Based on this characteristic, under external explosion-proof supplementary lighting, the portion containing gangue is opaque, while the area above the gangue layer allows relatively bright light to pass through. Through image binarization transformation, the mesh-transmitted image C is obtained, as shown... Figure 6 As shown in image C, the white areas represent the light-transmitting holes in the hopper, with diameters less than 10px. To facilitate the calculation of the shape of the area comprising the holes and reduce the interference of isolated points, morphological closing operations are performed on the image to connect the isolated white areas laterally, ultimately forming a large white area image D, as shown. Figure 6 As shown in D.

[0079] 5. In Figure 6 In image D, the largest bounding rectangle of the entire white area can be calculated. Then, the distance from the bottom edge of the rectangle to the top edge is calculated, such as... Figure 7 As shown, denoted as h. h is the final height of the gangue in the hopper and the distance from the top edge of the hopper.

[0080] 6. Based on the technical parameters of the jig and bucket elevator and the actual production conditions of the coal preparation plant, it was found during the experiment that when the h value in the final calculated image was 65px, the jig was already operating at full capacity. If the feed rate of the jig were slightly higher, it would exceed its maximum processing capacity. Therefore, the program set the threshold for h to 65. When the detected h value in the image is less than 65, the system considers that the feed rate of the jig has exceeded its maximum processing capacity, and an alarm needs to be issued and relevant personnel notified.

[0081] Example 2:

[0082] This invention provides an overfeed monitoring system for jigging machines in coal preparation plants, such as... Figure 8 As shown, the system includes a monitoring camera 2, an explosion-proof supplementary light 3, a system host 4, and an industrial network 5. The monitoring camera 2 is positioned directly in front of the gangue bucket elevator 1, and the explosion-proof supplementary light 3 is positioned above the gangue bucket elevator 1. The monitoring camera 2, system host 4, and industrial network 5 are electrically connected in sequence. The monitoring camera 2 is positioned directly in front of the gangue bucket elevator 1 at a relative distance of less than 2 meters, and is located 1.5 meters above the ground. The lens of the monitoring camera 2 is tilted upwards at a 15° angle, and the frame rate of the monitoring camera 2 is 25 frames per second. The system host 4 includes a waterproof and dustproof control box, an image analysis host, a switch, a display device, and an audible and visual alarm device. The image analysis host, switch, display device, and audible and visual alarm device are electrically connected in sequence and are all housed inside the waterproof and dustproof control box. There are two explosion-proof supplementary lights 3, each with a power of 25W. The gangue bucket elevator 1 is located below the jigging process. When it is working, the condition of the hopper is as follows: under no-load and normal conditions with gangue: Figure 9 As shown, the industrial network 5 is generally a ring structure, carrying data communication for all systems directly related to production, such as the PLC centralized control system, video monitoring system, and voice broadcasting system. This patent utilizes the industrial ring network to output the analyzed results to the PLC centralized control system.

[0083] This plan analyzes and judges the loading situation of the gangue bucket elevator, thereby indirectly inferring whether the real-time feeding of the upstream coal washing jig is excessive.

[0084] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0085] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0086] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0087] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for monitoring excessive feed to a jig in a coal preparation plant, characterized in that, include: Acquire real-time images of the jig to be monitored; The real-time position of the jig to be monitored is obtained using the real-time image of the jig to be monitored. The monitoring results of excessive feed to the jig, obtained based on the real-time location of the jig to be monitored, include: When there is a real-time location of the jig to be monitored that corresponds to the initial processed image of the jig to be monitored, the largest circumscribed rectangle of the white area in the connected image of the area of ​​the jig to be monitored corresponding to the initial processed image of the jig to be monitored is obtained as the area to be identified of the jig to be monitored. The distance from the bottom edge to the top of the largest circumscribed rectangle in the area to be identified of the jig to be monitored is obtained as the real-time data inside the jig to be monitored; Determine whether the real-time data inside the jig to be monitored is greater than the over-limit monitoring threshold. If it is, the over-limit monitoring result of the jig to be monitored is over-limit; otherwise, the over-limit monitoring result of the jig to be monitored is not over-limit. The over-detection threshold is 65px.

2. The method for monitoring excessive feed to a jig in a coal preparation plant as described in claim 1, characterized in that, The acquisition of real-time images of the jig to be monitored includes: Real-time monitoring video of the jig to be monitored is obtained using monitoring cameras; The real-time monitoring video is used to obtain real-time images of the jig machine to be monitored; The resolution of the real-time image of the jig to be monitored is 1920*1080.

3. The method for monitoring excessive feed to a jig in a coal preparation plant as described in claim 2, characterized in that, Obtaining the real-time location of the jig under monitoring using the real-time image of the jig under monitoring includes: The initial processed image of the jig to be monitored is obtained by performing initial processing calculations using the real-time image of the jig to be monitored. The real-time position of the jig to be monitored is obtained from the initial processed image of the jig to be monitored.

4. The method for monitoring excessive feed to a jig in a coal preparation plant as described in claim 3, characterized in that, The initial processed image of the jig to be monitored is obtained by performing initial processing calculations using the real-time image of the jig to be monitored, including: The transmitted light image of the jig under monitoring is obtained by binarizing the central region of the real-time image of the jig under monitoring. A morphological closing operation is performed on the transmitted light image of the jig to be monitored to obtain a connected image of the jig region to be monitored. The interconnected image of the jigging machine region to be monitored is used as the initial processing image of the jigging machine to be monitored. The number of light spots in the transmitted light image of the jig to be monitored is 2.

5. The method for monitoring excessive feed to a jig in a coal preparation plant as described in claim 4, characterized in that, The real-time position of the jig to be monitored is obtained from the initial processed image of the jig to be monitored, including: Determine whether the perimeter of the smallest bounding rectangle of the light spot in the initial processed image of the jig to be monitored is within the standard threshold. If so, use the initial processed image of the jig to be monitored as the real-time position of the jig to be monitored; otherwise, abandon the processing. The standard threshold ranges from 300px to 400px.

6. A system for monitoring excessive feed to a jig in a coal preparation plant, based on any one of claims 1-5, characterized in that, It includes a monitoring camera (2), a system host (4) and an industrial network (5). The monitoring camera (2) is located in front of the gangue bucket elevator (1). The monitoring camera (2), the system host (4) and the industrial network (5) are electrically connected in sequence.

7. The overfeed monitoring system for a jigging machine in a coal preparation plant as described in claim 6, characterized in that, The monitoring camera (2) is located directly in front of the gangue bucket elevator (1) and the relative distance is less than 2m. The monitoring camera (2) is located 1.5m above the ground. The lens of the monitoring camera (2) is tilted upward at 15°. The frame rate of the monitoring camera (2) is 25 frames / second.

8. The overfeed monitoring system for a jigging machine in a coal preparation plant as described in claim 7, characterized in that, The system host (4) includes a waterproof and dustproof control box, an image analysis host, a switch, a display device and an audible and visual alarm device. The image analysis host, the switch, the display device and the audible and visual alarm device are electrically connected in sequence and are all installed inside the waterproof and dustproof control box.

9. The overfeed monitoring system for a jigging machine in a coal preparation plant as described in claim 7, characterized in that, It also includes explosion-proof supplementary lighting (3), which is set above the gangue bucket elevator (1). The number of explosion-proof supplementary lighting (3) is 2, and the power of the explosion-proof supplementary lighting (3) is 25W.

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