Boiler combustion monitoring system and method

Abstract

The invention provides a boiler combustion monitoring system and method, and belongs to the technical field of combustion monitoring. The system comprises an image acquisition device which is arranged on a boiler and is used for acquiring an internal image of the boiler; the sound wave sensor array is arranged on the boiler and used for measuring the sound wave flying time of sound waves; the processor is connected with the image acquisition device and each sound wave sensor in the sound wave sensor array, and is used for obtaining a flue gas temperature flow field and a flue gas velocity flow field in the boiler based on the sound wave flying time, and determining the combustion state of the boiler based on the internal image of the boiler and the flue gas temperature flow field and the flue gas velocity flow field in the boiler; the combustion state of the boiler comprises a normal combustion state and an abnormal combustion state. The real-time combustion condition in the boiler hearth can be accurately mastered, comprehensive monitoring of boiler combustion is achieved, and the operation stability and safety of a unit are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of combustion monitoring, and in particular to a boiler combustion monitoring system and a boiler combustion monitoring method. Background Art

[0002] In recent years, in order to reduce the operating costs of coal-fired power plants, it is usually adopted to blend economic coal with high-heat coal. Due to the increase in the number of blended coals, the deviation from the designed coal quality is large, the fluctuation range of the blended coal quality is wide, and the coal source is complex. The blending of economic coals has led to an increase in high-ash and high-sulfur coal. If the blending is not done properly, it will cause furnace coking and high-temperature corrosion of the water-cooled wall. If the combustion is not adjusted properly, low-ash melting point coal is more likely to cause furnace coking, seriously affecting the safe operation of the unit. At present, the main combustion judgment of boiler combustion is based on the operating oxygen content, tail flue gas temperature distribution and steam-water system parameters. When there are problems such as boiler bias, local hypoxia, local overheating of boiler wall temperature, high unit operation energy consumption, uneven NOx generation, high-temperature corrosion, furnace coking, etc., the operating personnel lack specific monitoring means, which is not conducive to the monitoring and adjustment of the internal combustion conditions of the boiler and the specific analysis of safety problems, and cannot make targeted adjustments.

[0003] In addition, with the development of new energy, in order to meet the needs of stable operation of the power grid, the flexibility transformation of thermal power units has been accelerated and has become the main peak-shaving unit. For coal-fired units, the biggest problem in participating in deep peak-shaving is stable combustion at low load. At present, the judgment of stable combustion is mainly based on negative pressure and fire detection. The characteristics of ignition cannot be discovered in time, and the on-site operating personnel cannot intervene and adjust in advance. Once negative pressure fluctuations occur, it is difficult to recover in time, resulting in non-stop fire extinguishing. At the same time, the steam-water flow rate is low under low-load conditions, and the unit combustion heat deviation can easily cause overheating of the heating surface, posing a high safety hazard. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a boiler combustion monitoring system and method, so as to at least solve the above-mentioned problem that the main combustion judgment of the boiler combustion is based on the operating oxygen content, the tail smoke temperature distribution and the steam-water system parameters, which is not conducive to the monitoring and adjustment of the internal combustion conditions of the boiler and the specific analysis when safety problems occur, and targeted adjustments cannot be made.

[0005] In order to achieve the above object, the first aspect of the present invention provides a boiler combustion monitoring system, the system comprising: An image acquisition device, arranged on the boiler, for acquiring an image of the interior of the boiler; An acoustic wave sensor array is arranged on the boiler and is used to measure the acoustic wave transit time of the acoustic wave; A processor is connected to the image acquisition device and each acoustic wave sensor in the acoustic wave sensor array, and is used to obtain the flue gas temperature flow field and the flue gas velocity flow field inside the boiler based on the acoustic wave flight time, and determine the boiler combustion state based on the internal image of the boiler, the flue gas temperature flow field and the flue gas velocity flow field inside the boiler, and the boiler combustion state includes a normal combustion state and an abnormal combustion state.

[0006] Optionally, the system further includes: A display device connected to the processor, for displaying in real time an image of the interior of the boiler, and a flue gas temperature flow field and a flue gas velocity flow field inside the boiler; The alarm device is connected to the processor and is used to generate an alarm when an alarm instruction is received; the processor is also used to generate an alarm instruction when the boiler is in an abnormal combustion state.

[0007] Optionally, the image acquisition device includes: At least one camera is arranged on the boiler via a first mounting bracket and is used for collecting images inside the boiler.

[0008] Optionally, a shooting port is provided on the water-cooled wall of the boiler; The first mounting bracket comprises: A first sealing box, arranged on the water-cooled wall of the boiler and covering the shooting port; A guide rail, arranged on the first sealing box, wherein a slider is slidably arranged on the guide rail; The camera is arranged on the slider and can move along the guide rail with the slider. The shooting end of the camera is provided with a sleeve, the end of the sleeve passes through the first sealing box and the shooting port, and the camera realizes image shooting through the sleeve.

[0009] Optionally, a first cooling water pipe is sleeved on the outer wall of the sleeve, and the first cooling water pipe is used to cool the sleeve; The first sealing box is connected to a first compressed gas pipeline, and the first compressed gas pipeline is used to blow out compressed gas to clean and cool the first sealing box.

[0010] Optionally, the acoustic wave sensor array includes a plurality of acoustic wave sensor layers arranged sequentially from top to bottom, each acoustic wave sensor layer includes a plurality of horizontally arranged acoustic wave sensor layers, and each acoustic wave sensor is arranged on the boiler via a second mounting bracket for collecting acoustic wave flight time.

[0011] Optionally, a collection port is provided on the water-cooled wall of the boiler; The second mounting bracket comprises: A second sealing box is arranged on the water-cooled wall of the boiler and covers the collection port; A collecting tube is arranged on the second sealing box, the interior of the collecting tube is hollow, and the collecting end of the collecting tube is fixed on the boiler and is opposite to the collecting port; The acoustic wave sensor is arranged at the fixed end of the collecting tube, and a heat insulator is arranged between the acoustic wave sensor and the collecting tube.

[0012] Optionally, a second cooling water pipe is sleeved on the outer wall of the collection tube, and the second cooling water pipe is used to cool the collection tube; The collecting tube is connected to a second compressed gas pipeline, and the second compressed gas pipeline is used to blow out compressed gas to clean and cool the collecting tube.

[0013] A second aspect of the present invention provides a boiler combustion monitoring method, which is applied to the above-mentioned boiler combustion monitoring system, and the method comprises: Obtain images of the boiler interior and the acoustic wave flight time; The image processing algorithm is used to process the internal image of the boiler to obtain the flame shape recognition result; The propagation speed of sound waves is calculated using the sound wave flight time. According to a first preset relationship table, a smoke temperature value of a corresponding point is obtained, and based on the smoke temperature values ​​of all points, a smoke temperature flow field is obtained, wherein the first preset relationship table is used to characterize the corresponding relationship between the sound wave propagation velocity and the smoke temperature value; According to a second preset relationship table, a flue gas flow velocity value of a corresponding point is obtained, and based on the flue gas flow velocity values ​​of all points, a flue gas flow velocity flow field is obtained, wherein the second preset relationship table is used to characterize the corresponding relationship between the sound wave propagation velocity and the flue gas flow velocity value; Based on the flame shape recognition result, the flue gas temperature flow field and the flue gas velocity flow field, the boiler combustion state is determined, and the boiler combustion state includes a normal combustion state and an abnormal combustion state.

[0014] Optionally, determining the boiler combustion state based on the flame shape recognition result, the flue gas temperature flow field, and the flue gas velocity flow field includes: If any of the following conditions exist, the boiler combustion state is judged to be abnormal combustion state; The flame shape in the flame shape recognition result does not satisfy the preset shape; The flue gas temperature flow field does not satisfy the distribution law of decreasing from the center to the surrounding positions; The flue gas velocity flow field does not satisfy the distribution law of decreasing from the center position to the surrounding positions.

[0015] This scheme collects the internal image of the boiler and measures the sonic flight time of the sound wave, and obtains the flue gas temperature flow field and flue gas velocity flow field inside the boiler based on the sonic flight time. Finally, based on the internal image of the boiler, the flue gas temperature flow field and the flue gas velocity flow field inside the boiler, the boiler combustion state is determined, thereby comprehensively monitoring the actual combustion conditions of the boiler furnace, accurately grasping the real-time combustion conditions in the furnace, and providing data support and guidance for the unit's operation adjustment, combustion control, coal blending, and stable combustion adjustment, which can effectively improve the unit's operating stability and safety.

[0016] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1 It is a structural schematic diagram of the boiler combustion monitoring system provided by the present invention; Figure 2 is a structural schematic diagram of a first mounting bracket provided by the present invention; Figure 3 is a structural schematic diagram of a second mounting bracket provided by the present invention; Figure 4 The present invention is a flow chart of a boiler combustion monitoring method.

[0018] Description of Reference Numerals 1- boiler; 2- image acquisition device; 3- acoustic sensor array; 4-processor; 5-display device; 6-alarm device; 11-shooting port; 12-collection port; 21-camera; 22-first mounting bracket; 31-sonic wave sensor; 32-second mounting bracket; 221-first sealing box; 222-guide rail; 223-sliding block; 224- casing; 225- first cooling water pipe; 226- first compressed gas pipeline; 321 - second sealing box; 322 - collection tube; 323 - heat insulation body; 324 - second cooling water pipe; 325 - second compressed gas pipeline; 326 - reinforcing rib. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0020] In the embodiments of the present invention, unless otherwise specified, directional words such as "up, down, left, right" generally refer to the directions or positional relationships shown in the accompanying drawings, or the directions or positional relationships in which the inventive product is usually placed when in use.

[0021] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0022] The terms "parallel", "vertical", etc. do not mean that the components must be absolutely parallel or vertical, but can be slightly tilted. For example, "parallel" only means that its direction is more parallel than "vertical", and does not mean that the structure must be completely parallel, but can be slightly tilted.

[0023] The terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal, vertical or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In addition, the terms "roughly" and "basically" are intended to explain that the relevant content does not require absolute precision, but can have certain deviations. For example, "roughly equal" does not only mean absolute equality. Since it is difficult to achieve absolute "equality" in actual production and operation, there are generally certain deviations. Therefore, in addition to absolute equality, "roughly equal" also includes the above-mentioned situation with certain deviations. Taking this as an example, in other cases, unless otherwise specified, the terms "roughly" and "basically" have similar meanings to the above.

[0025] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] Figure 1 It is a structural schematic diagram of the boiler combustion monitoring system provided by the present invention; Figure 2 is a structural schematic diagram of a first mounting bracket provided by the present invention; Figure 3 is a structural schematic diagram of a second mounting bracket provided by the present invention; Figure 4The present invention is a flow chart of a boiler combustion monitoring method.

[0027] like Figure 1 As shown, this embodiment provides a boiler combustion monitoring system, the system comprising: An image acquisition device 2, arranged on the boiler 1, for acquiring an image of the interior of the boiler; The acoustic wave sensor array 3 is arranged on the boiler 1 and is used to measure the acoustic wave transit time of the acoustic wave; The processor 4 is connected to the image acquisition device 2 and each acoustic wave sensor in the acoustic wave sensor array 3, and is used to obtain the flue gas temperature flow field and the flue gas velocity flow field inside the boiler 1 based on the acoustic wave flight time, and determine the boiler combustion state based on the internal image of the boiler, the flue gas temperature flow field and the flue gas velocity flow field inside the boiler 1, and the boiler combustion state includes a normal combustion state and an abnormal combustion state.

[0028] Specifically, the image acquisition device 2 is arranged on the boiler 1 and is aimed at the furnace of the boiler to collect images during the combustion process; the acoustic wave sensor array 3 is also arranged on the boiler 1 to collect the acoustic wave flight time; the image acquisition device 2 and the acoustic wave sensor array 3 are both connected to the processor 4, and the collected data is sent to the processor 4, and the processor 4 analyzes the received data to determine the combustion state of the boiler, and the boiler combustion state includes a normal combustion state and an abnormal combustion state. Through the above scheme, non-contact measurement is adopted, which can fully understand the actual combustion conditions of the furnace, accurately grasp the real-time combustion conditions in the furnace, provide data support and guidance for operation adjustment, combustion control, coal blending, and stable combustion adjustment, and can adjust the furnace combustion in real time to avoid lag problems, which greatly enhances the unit operation safety and the blending ratio of economic coal.

[0029] Furthermore, the system further comprises: A display device 5, connected to the processor 4, for displaying the internal image of the boiler, and the flue gas temperature flow field and flue gas velocity flow field inside the boiler 1 in real time; The alarm device 6 is connected to the processor 4 and is used to generate an alarm when receiving an alarm instruction; the processor 4 is also used to generate an alarm instruction when the boiler is in an abnormal combustion state.

[0030] Specifically, in this embodiment, the system is also provided with a display device 5 and an alarm device 6 connected to the processor 4. The display device 5 and the alarm device 6 are arranged in the monitoring room. The display device 5 can display the internal image of the boiler, and the flue gas temperature flow field and the flue gas velocity flow field inside the boiler 1 in real time, so that the on-duty personnel can obtain data intuitively; in addition, the processor 4 is also used to generate an alarm instruction when the boiler is in an abnormal combustion state, and the alarm device 6 generates an alarm when receiving the alarm instruction, so as to prompt the on-duty personnel. Among them, the display device 5 also has the functions of review, search, background storage, output, etc.

[0031] Furthermore, the image acquisition device 2 comprises: At least one camera 21 is mounted on the boiler 1 via a first mounting bracket 22 and is used to capture images of the interior of the boiler.

[0032] Specifically, in this embodiment, the image acquisition device 2 is configured as a camera 21 , which can realize continuous image acquisition, and is arranged on the boiler 1 through a first mounting bracket 22 , and the first mounting bracket 22 can adjust the shooting angle of the camera 21 .

[0033] In another embodiment, two cameras 21 are provided, and the two cameras 21 are arranged opposite to each other on the boiler 1 to achieve more comprehensive monitoring.

[0034] Furthermore, if Figure 2 As shown, a shooting port 11 is provided on the water-cooled wall of the boiler 1; The first mounting bracket 22 comprises: A first sealing box 221 is disposed on the water-cooled wall of the boiler 1 and covers the photographing port 11; A guide rail 222 is provided on the first sealing box 221, and a slider 223 is slidably provided on the guide rail 222; The camera 21 is arranged on the slider 223 and can move along the guide rail 222 with the slider 223 . A sleeve 224 is arranged at the shooting end of the camera 21 . The end of the sleeve 224 passes through the first sealing box 221 and the shooting port 11 . The camera 21 captures images through the sleeve 224 .

[0035] Specifically, in this embodiment, first, a shooting port 11 is opened on the water-cooled wall of the boiler 1, and a camera 21 is set, then a shooting port 11 is opened; the first sealing box 221 is an arc-shaped structure with a concave space, and is set on the water-cooled wall of the boiler 1 and covers the shooting port 11, which can effectively prevent heat from being conducted outward; the guide rail 222 is set on the outer surface of the first sealing box 221, and a slider 223 is slidably set on the guide rail 222, and the camera 21 is set on the slider 223 and can move along the guide rail 222 with the slider 223; in order to improve the image acquisition quality, a sleeve 224 is set at the shooting end of the camera 21, and the end of the sleeve 224 passes through the first sealing box 221 and the shooting port 11, and the camera 21 realizes image capture through the sleeve 224. In the process of the camera 21 moving along the guide rail 222 with the slider 223, the imaging focal length can be adjusted to capture a clear image and ensure image quality.

[0036] More specifically, the guide rail 222 and the first sealing box 221 are installed and fixed by bolts, and during the installation process, the angle of the guide rail 222 relative to the first sealing box 221 is adjusted to adjust the shooting angle of the camera 21.

[0037] The slider 223 may adopt a linear motor module, or a driving mechanism (such as an electric cylinder, a pneumatic cylinder, etc.) to drive the slider 223 .

[0038] Furthermore, a first cooling water pipe 225 is sleeved on the outer wall of the sleeve 224, and the first cooling water pipe 225 is used to cool the sleeve 224; The first sealed box 221 is connected to a first compressed gas pipeline 226 , and the first compressed gas pipeline 226 is used to blow out compressed gas to clean and cool the first sealed box 221 .

[0039] Specifically, in this embodiment, since the temperature is high when the boiler is burning, the camera 21 and the sleeve 224 work in a high temperature environment, which will greatly reduce the service life. Therefore, a first cooling water pipe 225 is provided on the outer wall of the sleeve 224 to cool the sleeve 224 by circulating cooling water. In addition, since the combustion of the boiler will generate dust, a gas inlet is opened on the first sealing box 221 and connected to the first compressed gas pipeline 226. The first compressed gas pipeline 226 provides compressed gas for backblowing to achieve cooling and dust removal.

[0040] Furthermore, the acoustic wave sensor array includes a plurality of acoustic wave sensor layers arranged in sequence from top to bottom, each acoustic wave sensor layer includes a plurality of horizontally arranged acoustic wave sensors 31, and each acoustic wave sensor 31 is arranged on the boiler 1 through a second mounting bracket 32 ​​for collecting acoustic wave flight time.

[0041] Specifically, the acoustic wave sensor array includes a plurality of acoustic wave sensor layers arranged in sequence from top to bottom, and each acoustic wave sensor layer includes a plurality of acoustic wave sensors 31 arranged at the same horizontal height. Acquisition of the acoustic wave flight time by the multi-layer acoustic wave sensors 31 can ensure data volume and acquisition accuracy.

[0042] Preferably, in one embodiment, the acoustic wave sensor array includes four acoustic wave sensor layers arranged sequentially from top to bottom, wherein data collected by the first acoustic wave sensor layer and the second acoustic wave sensor layer are used to calculate the flue gas temperature flow field inside the boiler 1; data collected by the third acoustic wave sensor layer and the fourth acoustic wave sensor layer are used to calculate the flue gas velocity flow field inside the boiler 1.

[0043] Furthermore, if Figure 3 As shown, the water-cooled wall of the boiler 1 is provided with collection ports 12, and the number of the collection ports 12 is consistent with the number of the acoustic wave sensors 31; The second mounting bracket 32 ​​comprises: A second sealing box 321 is disposed on the water-cooled wall of the boiler 1 and covers the collection port 12; A collecting tube 322 is provided on the second sealing box 321. The collecting tube 322 is hollow inside. The collecting end of the collecting tube 322 is fixed on the boiler 1 and is opposite to the collecting port 12. The acoustic wave sensor 31 is disposed at the fixed end of the collecting tube 322 , and a heat insulator 323 is disposed between the acoustic wave sensor 31 and the collecting tube 322 .

[0044] Specifically, in this embodiment, the second sealing box 321 is an arc-shaped structure with a concave space, which covers the collection port 12 and can effectively prevent heat from being conducted outward; and the acoustic wave sensor 31 is supported and fixed by the collection tube 322, and the signal is collected by the internal hollow collection tube 322, which can ensure the collection effect; the heat insulation body 323 can block heat and protect the acoustic wave sensor 31 to avoid overheating.

[0045] In another embodiment, reinforcing ribs 326 are further provided between the second sealing box 321 and the water-cooled wall of the boiler 1 to increase the structural strength.

[0046] Furthermore, a second cooling water pipe 324 is sleeved on the outer wall of the collection tube 322, and the second cooling water pipe 324 is used to cool the collection tube 322; The collecting tube 322 is connected to a second compressed gas pipeline 325 , and the second compressed gas pipeline 325 is used to blow out compressed gas to clean and cool the collecting tube 322 .

[0047] Specifically, in this embodiment, since the temperature is high when the boiler is burning, the collecting tube 322 works in a high temperature environment, which will greatly reduce the service life. Therefore, a second cooling water pipe 324 is provided on the outer wall of the collecting tube 322 to cool the collecting tube 322 by circulating cooling water. In addition, since the combustion of the boiler will generate dust, a gas inlet is opened on the collecting tube 322 and connected to the second compressed gas pipeline 325. The second compressed gas pipeline 325 provides compressed gas for backblowing to achieve cooling and dust removal.

[0048] This embodiment also provides a boiler combustion monitoring method, which is applied to the above-mentioned boiler combustion monitoring system. Figure 4 As shown, the method includes: Obtain images of the boiler interior and the acoustic wave flight time; The image processing algorithm is used to process the internal image of the boiler to obtain the flame shape recognition result; The propagation speed of sound waves is calculated using the sound wave flight time. According to the first preset relationship table, the flue gas temperature value of the corresponding point is obtained, and the flue gas temperature flow field is obtained based on the flue gas temperature values ​​of all points. The first preset relationship table is used to characterize the corresponding relationship between the sound wave propagation speed and the smoke gas temperature value; specifically, since the refraction of the sound wave propagating in the uneven temperature field will cause the speed to change, according to the fixed path distance and propagation time, the propagation speed can be obtained, and then the temperature of the temperature field can be calculated; the first preset relationship table is obtained by fitting the historical sound wave propagation speed and the historical smoke gas temperature value; the smoke gas temperature flow field can be a two-dimensional temperature gradient (only one layer of sound wave sensor layer) or a three-dimensional temperature gradient (at least two layers of sound wave sensor layers), and constructing a three-dimensional temperature gradient can ensure more accurate monitoring. For example, when there are two layers of sound wave sensor layers, by generating the temperature field of each layer and then fusing it with the sound wave measurement points arranged crosswise above and below, a three-dimensional temperature gradient can be simulated, and then a three-dimensional temperature field model can be established.

[0049] According to the second preset relationship table, the flue gas velocity value of the corresponding point is obtained, and the flue gas velocity flow field is obtained based on the flue gas velocity values ​​of all points. The second preset relationship table is used to characterize the corresponding relationship between the sound wave propagation velocity and the flue gas velocity value. The second preset relationship table is obtained by fitting the historical sound wave propagation velocity and the historical flue gas velocity value; specifically, in this embodiment, the flue gas velocity on different paths is calculated by the algorithm based on the correlation of the sound wave flight time between the two sections and the relationship between the sound wave propagation velocity and the flue gas velocity, and the flue gas velocity flow field distribution in the area is obtained by the inversion algorithm (establishing a velocity gradient model).

[0050] Based on the flame shape recognition result, the flue gas temperature flow field and the flue gas velocity flow field, the boiler combustion state is determined, and the boiler combustion state includes a normal combustion state and an abnormal combustion state.

[0051] Further, based on the flame shape recognition result, the flue gas temperature flow field and the flue gas velocity flow field, determining the boiler combustion state includes: If any of the following conditions exist, the boiler combustion state is judged to be abnormal combustion state; The flame shape in the flame shape recognition result does not satisfy the preset shape; The flue gas temperature flow field does not satisfy the distribution law of decreasing from the center to the surrounding positions; The flue gas velocity flow field does not satisfy the distribution law of decreasing from the center position to the surrounding positions.

[0052] Specifically, in this embodiment, the flame of the hearth furnace coal powder has certain shape characteristics when it is burning normally. According to the analysis of historical images, multiple flame shape libraries of normal combustion can be obtained, and the flame shape in the flame shape recognition result is compared with the preset shape in the flame shape library. If the shapes match, it means that the combustion state of the boiler is normal. In addition, under normal combustion conditions, the temperature in the middle of the boiler furnace is high and gradually decreases toward the peripheral positions. Therefore, if the flue gas temperature flow field does not satisfy the distribution law of decreasing from the center position to the surrounding positions or the flue gas velocity flow field does not satisfy the distribution law of decreasing from the center position to the surrounding positions, it means that the boiler is in an abnormal combustion state.

[0053] More specifically, in a specific implementation, it includes two high-temperature flame monitoring optical cameras with a large-angle adjustment function, which are installed relative to a specific area on the boiler water-cooled wall to achieve a visual display of the actual combustion conditions in the furnace, and can monitor and measure the furnace combustion conditions in real time. The observation range can be adjusted according to demand, and full-angle observation of the furnace wall and burner can be achieved. The acoustic wave sensor array includes: a non-contact acoustic wave online monitoring temperature field module and a non-contact acoustic wave online monitoring velocity field module; wherein, the non-contact acoustic wave online monitoring temperature field module includes 2N acoustic wave sensors, which are arranged at a specific position of the furnace, divided into two layers, upper and lower, with N measuring points each, and by measuring the acoustic wave flight time on the acoustic wave propagation path, the speed of acoustic wave propagation is obtained according to the path distance, and then the temperature to be measured is obtained by using the single-valued function relationship between the acoustic wave propagation speed and the medium temperature, and by this measurement method, the real physical gas temperature in the boiler furnace is dynamically measured online, and a three-dimensional temperature field model can be generated based on the two-dimensional temperature field; the non-contact acoustic wave online monitoring velocity field module also includes 2N acoustic wave sensors, which are divided into two layers, upper and downstream, at a certain distance, at a specific position of the furnace, and each layer is arranged with N measuring points, and the correlation of the acoustic wave flight time between the two cross sections is used to obtain the temperature to be measured. According to the relationship between the speed of sound wave propagation and the flue gas velocity, the flue gas velocity on different paths is calculated by the algorithm, the velocity flow field distribution in the area is obtained by the inversion algorithm, and the full-section flow data of the furnace outlet is accurately measured; the data acquisition module and the data diagnosis and processing module can collect the images and data of the optical visualization monitoring of the furnace, the test data of the combustion temperature field and the velocity field, and establish the overall combustion monitoring and diagnosis model of the furnace after data processing (for example: the temperature and velocity in a certain section should be distributed more evenly, the central velocity is higher, and the diffusion to the wall will gradually decrease. The smaller the change trend, the more uniform the temperature field and velocity field; on the contrary, it means that there is a problem with the combustion, and the air flow rate, angle and other measures can be adjusted to ensure uniform combustion, and the temperature field and velocity field tend to be uniform), which can timely diagnose the combustion situation in the furnace, and guide the combustion adjustment and steam temperature adjustment in real time. And it can comprehensively judge the effect of coal blending, further reasonably formulate the blending plan, and improve the safety and economy of economic coal blending. The dual-medium cooling module and the corresponding control systems, pipelines, valves, display screens, computer storage devices and other auxiliary facilities are used to ensure the safe, reliable and normal operation of the system and the display and output of images and data.

[0054] Those skilled in the art will understand that all or part of the steps in the method for implementing the above-mentioned embodiments can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions for making a single-chip microcomputer, a chip or a processor execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0055] The optional embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the technical concept of the embodiments of the present invention, the technical scheme of the embodiments of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0056] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A boiler combustion monitoring system, characterized in that: The system comprises: An image acquisition device (2) is arranged on the boiler (1) and is used to acquire an image of the interior of the boiler; An acoustic wave sensor array (3) is arranged on the boiler (1) and is used to measure the acoustic wave transit time of the acoustic wave; A processor (4) is connected to the image acquisition device (2) and each acoustic wave sensor in the acoustic wave sensor array (3), and is used to obtain the flue gas temperature flow field and the flue gas velocity flow field inside the boiler (1) based on the acoustic wave flight time, and to determine the boiler combustion state based on the boiler internal image, the flue gas temperature flow field and the flue gas velocity flow field inside the boiler (1), wherein the boiler combustion state includes a normal combustion state and an abnormal combustion state.

2. The boiler combustion monitoring system according to claim 1, characterized in that: The system further comprises: A display device (5) connected to the processor (4) and used for displaying in real time an image of the interior of the boiler, and a flue gas temperature flow field and a flue gas velocity flow field inside the boiler (1); An alarm device (6) is connected to the processor (4) and is used to generate an alarm when an alarm instruction is received; the processor (4) is also used to generate an alarm instruction when the boiler is in an abnormal combustion state.

3. The boiler combustion monitoring system according to claim 1, characterized in that: The image acquisition device (2) comprises: At least one camera (21) is arranged on the boiler (1) via a first mounting bracket (22) and is used to capture images of the interior of the boiler.

4. The boiler combustion monitoring system according to claim 3, characterized in that: A shooting port (11) is provided on the water-cooled wall of the boiler (1); The first mounting bracket (22) comprises: A first sealing box (221) is arranged on the water-cooled wall of the boiler (1) and covers the photographing port (11); A guide rail (222) is arranged on the first sealing box (221), and a slider (223) is slidably arranged on the guide rail (222); The camera (21) is arranged on the slider (223) and can move along the guide rail (222) with the slider (223); a sleeve (224) is arranged at the shooting end of the camera (21); an end of the sleeve (224) passes through the first sealing box (221) and the shooting port (11); and the camera (21) shoots images through the sleeve (224).

5. The boiler combustion monitoring system according to claim 4, characterized in that: A first cooling water pipe (225) is sleeved on the outer wall of the sleeve (224), and the first cooling water pipe (225) is used to cool the sleeve (224); The first sealed box (221) is connected to a first compressed gas pipeline (226), and the first compressed gas pipeline (226) is used to blow out compressed gas to clean and cool the first sealed box (221).

6. The boiler combustion monitoring system according to claim 1, characterized in that: The acoustic wave sensor array comprises a plurality of acoustic wave sensor layers arranged in sequence from top to bottom, each acoustic wave sensor layer comprises a plurality of horizontally arranged acoustic wave sensors (31), and each acoustic wave sensor (31) is arranged on the boiler (1) via a second mounting bracket (32) and is used to collect acoustic wave flight time.

7. The boiler combustion monitoring system according to claim 6, characterized in that: A collection port (12) is provided on the water-cooled wall of the boiler (1); The second mounting bracket (32) comprises: A second sealing box (321) is arranged on the water-cooled wall of the boiler (1) and covers the collection port (12); A collecting tube (322) is arranged on the second sealing box (321); the interior of the collecting tube (322) is hollow; a collecting end of the collecting tube (322) is fixed on the boiler (1) and is opposite to the collecting port (12); The acoustic wave sensor (31) is arranged at the fixed end of the collection tube (322), and a heat insulator (323) is arranged between the acoustic wave sensor (31) and the collection tube (322).

8. The boiler combustion monitoring system according to claim 7, characterized in that: A second cooling water pipe (324) is sleeved on the outer wall of the collecting tube (322), and the second cooling water pipe (324) is used to cool the collecting tube (322); The collection tube (322) is connected to a second compressed gas pipeline (325), and the second compressed gas pipeline (325) is used to blow out compressed gas to clean and cool the collection tube (322).

9. A boiler combustion monitoring method, applied to the boiler combustion monitoring system according to any one of claims 1 to 8, characterized in that: The method comprises: Obtain images of the boiler interior and the acoustic wave flight time; The image processing algorithm is used to process the internal image of the boiler to obtain the flame shape recognition result; The propagation speed of sound waves is calculated using the sound wave flight time. According to a first preset relationship table, a smoke temperature value of a corresponding point is obtained, and based on the smoke temperature values ​​of all points, a smoke temperature flow field is obtained, wherein the first preset relationship table is used to characterize the corresponding relationship between the sound wave propagation velocity and the smoke temperature value; According to a second preset relationship table, a flue gas flow velocity value of a corresponding point is obtained, and based on the flue gas flow velocity values ​​of all points, a flue gas flow velocity flow field is obtained, wherein the second preset relationship table is used to characterize the corresponding relationship between the sound wave propagation velocity and the flue gas flow velocity value; Based on the flame shape recognition result, the flue gas temperature flow field and the flue gas velocity flow field, the boiler combustion state is determined, and the boiler combustion state includes a normal combustion state and an abnormal combustion state.

10. The boiler combustion monitoring method according to claim 9, characterized in that: Determining the combustion state of the boiler based on the flame shape recognition result, the flue gas temperature flow field and the flue gas velocity flow field includes: If any of the following conditions exist, the boiler combustion state is judged to be abnormal combustion state; The flame shape in the flame shape recognition result does not satisfy the preset shape; The flue gas temperature flow field does not satisfy the distribution law of decreasing from the center to the surrounding positions; The flue gas velocity flow field does not satisfy the distribution law of decreasing from the center position to the surrounding positions.

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