Fly ash throttling and reinforced collecting device and method for boiler tail flue

Abstract

The invention relates to the technical field of coal-fired power plant boiler equipment, in particular to a fly ash throttling and intensified collecting device and method for a boiler tail flue, the fly ash throttling and intensified collecting device is installed in a low-temperature horizontal section flue of the boiler tail flue, and the fly ash throttling and intensified collecting device comprises a moving track, a fly ash collecting device and a fly ash collecting device, the moving track is fixedly arranged on the inner wall of the bottom of the low-temperature horizontal section flue and extends in the length direction of the flue; the sliding execution assembly is movably arranged on the moving track; a function executor; the ash collecting tank is arranged at one end of the bottom of the low-temperature horizontal section flue; the adjusting plate serving as a function executing part can horizontally move, vertically lift and rotate around the shaft along the flue under the control of the driving mechanism, so that the position, the height and the inclination angle of the adjusting plate in the flue can be dynamically adjusted according to real-time working conditions, and the single adjusting plate can adjust the position, the height and the inclination angle of the flue through posture transformation. Seamless switching is achieved between the two roles of a flow guide throttling plate and an ash scraping and obstacle removing plate.

Description

Technical Field

[0001] This invention relates to the field of boiler equipment technology in coal-fired power plants, specifically to a fly ash throttling and enhanced collection device and method for the tail flue of a boiler. Background Technology

[0002] With the deepening of my country's energy structure transformation, coal-fired power units generally undertake deep peak-shaving tasks. As the demand for deep peak-shaving in coal-fired units becomes the norm, the flue gas velocity in the tail flue decreases when the boiler operates at low loads, leading to a decline in fly ash carrying capacity. This is especially true in the horizontal flue and bends after the economizer, where fly ash deposition becomes increasingly prominent. The deposited fly ash not only reduces the flue flow area, increases system resistance, and affects economic operation, but its caking and collapse can also impact and wear down downstream SCR catalysts and air preheaters. In severe cases, it may even require boiler shutdown for manual ash removal, threatening the safe and stable operation of the unit.

[0003] Currently, the technical means to address this problem have significant limitations: commonly used passive structures such as fixed guide vanes and interception nets cannot adapt to wide load variations, are ineffective at low loads, and have high resistance at high loads; moreover, existing solutions are limited in function and lack coordination. For example, fixed guide vanes cannot clean the ash accumulation downstream of themselves, and local soot blowers cannot cover the bottom of long-distance flues, creating blind spots in prevention and control; at the same time, the control methods are simple, relying heavily on timed operation, and lack the intelligent closed-loop control capability to make precise interventions based on real-time flow field and ash accumulation status, thus belonging to a post-event processing mode.

[0004] Therefore, existing technologies lack a comprehensive flue gas fly ash treatment system capable of adaptive adjustment under all operating conditions, integrating mechanical and pneumatic methods, and possessing intelligent closed-loop control capabilities. Developing a device that can intervene in deposition at its source and achieve online cleaning and intelligent coordination is urgently needed and of significant value for ensuring the safe, environmentally friendly, and economical operation of thermal power units under deep peak shaving conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a fly ash throttling and enhanced collection device and method for boiler tail flue, so as to solve the shortcomings mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a fly ash throttling and enhanced collection device for a boiler tail flue, installed in the low-temperature horizontal section of the boiler tail flue, comprising:

[0007] The movable track is fixedly installed on the bottom inner wall of the low-temperature horizontal section flue and extends along the length of the flue.

[0008] The sliding actuator assembly is movably mounted on the moving track;

[0009] The functional actuator is an adjustment plate connected to the sliding actuator assembly. The adjustment plate is configured to change its spatial attitude and position in the flue under the drive of the sliding actuator assembly, so as to selectively perform active throttling of flue gas flow or mechanical scraping of ash accumulated on the bottom wall of the flue.

[0010] An ash collection trough is located at one end of the bottom of the low-temperature horizontal section flue.

[0011] The sliding execution assembly includes:

[0012] The sliding block is slidably engaged with the moving track.

[0013] A movable plate is slidably connected to the sliding block in the vertical direction;

[0014] A vertical drive mechanism is used to drive the moving plate to move up and down relative to the sliding block;

[0015] A horizontal drive mechanism is used to drive the sliding block to move horizontally along the moving track;

[0016] A plate angle adjustment mechanism is used to drive the adjustment plate to rotate relative to the moving plate about a horizontal axis;

[0017] An air blowing slot is provided on the side wall at the beginning of the low-temperature horizontal section flue, and an air blowing device is installed at the air blowing slot for injecting airflow into the flue.

[0018] The side of the moving track is equipped with an air curtain generating device, which is used to spray gas into the gap between the sliding block and the inner wall of the flue to form an air curtain.

[0019] Preferably, the vertical drive mechanism includes:

[0020] The toothed column is parallel to the moving track in its length direction, and its two ends are rotatably connected to the bottom or side wall of the low-temperature horizontal section flue through bearing supports.

[0021] The first drive motor has its output end connected to one end of the gear column in a transmission connection.

[0022] The movable plate has movable teeth that mesh with the tooth column on the side facing the tooth column.

[0023] Preferably, the horizontal drive mechanism and the plate angle adjustment mechanism are driven by a bidirectional motor;

[0024] The bidirectional motor is fixedly mounted on the movable plate and has a first output terminal and a second output terminal that are coaxial and output in opposite directions.

[0025] The plate angle adjustment mechanism includes a drive rod, one end of which is connected to the first output end of the bidirectional motor, and the other end is hinged to the adjustment plate, forming a first rotating pair that drives the adjustment plate to rotate.

[0026] The horizontal drive mechanism includes:

[0027] The drive gear is fixedly mounted on the second output end of the bidirectional motor;

[0028] The driven gear meshes with the driving gear and is rotatably mounted on the sliding block via a rotating shaft;

[0029] The linkage mechanism has its first end connected to the side wheel surface of the driven gear, and its second end hinged to the fixed structure of the moving track or the low-temperature horizontal section flue.

[0030] The rotational motion of the driven gear is converted into the reciprocating linear motion of the sliding block along the moving track by the linkage mechanism.

[0031] Preferably, the linkage mechanism includes a first linkage and a second linkage;

[0032] One end of the first connecting rod is fixedly connected to the side wheel surface of the driven gear, and the other end is hinged to one end of the second connecting rod.

[0033] The other end of the connecting rod is hinged to a hinge seat fixedly installed on the inner wall of the low-temperature horizontal section flue.

[0034] Preferably, the blowing device includes a high-pressure air source and a jet grille;

[0035] The jet grille is installed inside the air blowing slot via an angle adjustment component;

[0036] The inner edge of the air blowing slot is provided with a high-temperature resistant elastic seal, and the periphery of the jet grille is in elastic contact with the seal to achieve a seal.

[0037] Preferably, the angle adjustment component includes:

[0038] A fixing rod, one end of which is fixedly connected to the back of the jet grille;

[0039] A fixing plate is fixed to the outer wall of the low-temperature horizontal section flue;

[0040] An arc-shaped limiting block is fixedly connected to the middle of the fixing rod, and an arc-shaped groove is provided on it;

[0041] The limiting post is fixed to the fixing plate and slides through the arc-shaped groove;

[0042] A threaded block is fixedly connected to the end of the fixing rod away from the jet grille, and a threaded hole is provided in its middle part;

[0043] The screw engages with the threaded hole of the threaded block;

[0044] A support plate, one end of the screw being rotatably connected to the support plate via a bearing;

[0045] The second drive motor is mounted on the support plate, and its output end is connected to the screw drive.

[0046] One end of the support plate is rotatably connected to the fixed plate; the rotation of the screw drives the threaded block to move along its axial direction, and then drives the jet grille to rotate around the central axis of the limiting post through the fixed rod.

[0047] Preferably, the air curtain generating device includes an air curtain nozzle arranged along the length of the moving track, and the air curtain nozzle is provided with a plurality of air curtain nozzles facing the gap between the sliding block and the inner wall of the flue; the air curtain nozzle is connected to a high-pressure gas source through a flexible pipeline.

[0048] Preferably, it also includes an intelligent control unit, which is electrically connected to the control valves of the first drive motor, the bidirectional motor, the second drive motor, the high-pressure air source, and the air curtain generating device.

[0049] A method for applying the above-mentioned fly ash throttling and enhanced collection device for boiler tail flue, the method comprising:

[0050] Real-time acquisition of operating parameters within the flue, including differential pressure distribution signals, flow velocity distribution signals, and fly ash deposition thickness distribution signals in different regions of the flue.

[0051] Based on the comparison and analysis of the operating parameters and preset thresholds, a decision is made to enter the corresponding working mode; the working modes include cruise intervention mode, planned dust removal mode and emergency purging mode;

[0052] If the decision is to enter the cruise intervention mode, then the first cooperative control strategy will be executed:

[0053] Based on the real-time acquired signals of differential pressure distribution, flow velocity distribution, and fly ash deposition thickness distribution, target areas requiring intervention within the flue are identified. These target areas include areas with abnormal flow fields and areas at risk of ash accumulation.

[0054] Control the sliding block to move along the moving track to the target area;

[0055] The plate angle adjustment mechanism is controlled to adjust the tilt angle of the adjustment plate in order to optimize the flow field in the target area;

[0056] Simultaneously, depending on the type of the target area, the jet grille is controlled to inject airflow into the flue with corresponding flow rate and angle; wherein, when the target area is an area with abnormal flow field, the jet grille is controlled to inject with a first flow rate and a first angle to form a wall-adhering air cushion in the flue inlet area; when the target area is an area with ash accumulation risk, the injection angle of the jet grille is adjusted to enhance the airflow in the area with ash accumulation risk.

[0057] The air curtain generating device is controlled to operate at a first pressure;

[0058] If the decision enters the planned dust removal mode, then the second collaborative control strategy is executed:

[0059] Control the adjustment plate to rotate to the cleaning angle and lower it to contact the bottom of the flue;

[0060] At the same time, the sliding block is controlled to move horizontally back and forth along the moving track to continuously scrape the ash at the bottom of the flue to the ash collection trough;

[0061] During the dust removal process, the jet grille is controlled to perform auxiliary jetting, and its jetting angle can be adjusted as needed to assist in the conveying of fly ash.

[0062] In this mode, the air curtain generator is controlled to operate at a second pressure higher than the first pressure;

[0063] If the decision is to enter the emergency purging mode, then the third collaborative control strategy will be executed:

[0064] The blockage area is located based on the rapidly increasing differential pressure signal;

[0065] The jet grille is controlled to blow powerfully at maximum flow and adjusted to the optimal cleaning angle for the clogged area.

[0066] Simultaneously, the adjusting plate is controlled to rise and rotate to the avoidance position, and the air curtain generating device is controlled to maintain or enhance the air curtain.

[0067] Compared with the prior art, the beneficial effects of the present invention are:

[0068] This invention constructs an intelligent, proactive execution system centered around a multi-degree-of-freedom adjustable regulating plate. Under the control of a drive mechanism, this regulating plate can move horizontally along the flue, rise and fall vertically, and rotate around its axis, thus dynamically adjusting its position, height, and inclination angle within the flue according to real-time operating conditions. This design allows the single regulating plate to seamlessly switch between two roles: a "flow guide and throttling plate" and a "scraper and clearing plate." At a high inclination angle, it effectively throttles and guides the upstream flue gas, actively optimizing the downstream flow field to prevent fly ash deposition. At a low angle and descending to contact the bottom surface, it transforms into a scraper, pushing the accumulated ash at the bottom to the ash collection trough as it moves. The flexibility and multi-functionality of this core component fundamentally solve the problems of traditional fixed flow guides or interception devices being unable to adapt to load changes and having limited functionality. It achieves a shift from passive fixation to proactive intelligence, and from post-event cleaning to pre-event intervention, significantly improving the comprehensive management capabilities of flue fly ash deposition and the adaptability of unit operation. Attached Figure Description

[0069] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a perspective view of the overall structure of the present invention; Figure 3 This is a cross-sectional view of the overall structure of the present invention; Figure 4 This is a cross-sectional view of the low-temperature horizontal section flue of the present invention; Figure 5 This is a schematic diagram of the air blowing device installation structure in this invention; Figure 6 This is a schematic diagram of the installation structure of the vertical drive mechanism in this invention; Figure 7 This is a schematic diagram of the installation structure of the horizontal drive mechanism in this invention.

[0070] In the diagram: 1. Moving track; 2. Adjusting plate; 3. Ash collection trough; 4. Air blowing device; 5. Air curtain generating device; 6. Gear column; 7. First drive motor; 8. Bidirectional motor; 9. Driving gear; 10. Driven gear; 11. Linkage mechanism; 41. High-pressure air source; 42. Jet grille; 43. Fixed rod; 44. Screw; 45. Second drive motor; 46. Fixed plate; 47. Arc-shaped limit block; 48. Limiting post; 49. Threaded block; 51. Air curtain nozzle; 52. Air curtain nozzle; 100. Low-temperature horizontal flue; 101. Sliding block; 102. Moving plate; 410. Support plate; 420. Air blowing slot; 471. Arc-shaped slot; 701. Bearing support; 812. First output end; 822. Second output end; 1021. Moving gear; 1101. Linkage one; 1102. Linkage two. Detailed Implementation

[0071] 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, and 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.

[0072] like Figures 1 to 3 As shown in the background art, this invention addresses the problem of fly ash deposition and caking in the horizontal flue of a boiler tail section during low-load operation, where fixed devices cannot adaptively adjust and lack effective online cleaning methods. This invention provides a fly ash throttling and enhanced collection device for the boiler tail flue. This device is mainly installed in the working section of the boiler tail flue where the flue gas temperature has significantly decreased and is at a medium-low temperature level, such as the flue after the selective catalytic reduction (SCR) reactor and before the air preheater, or within a longer low-temperature horizontal section of the flue after the low-temperature economizer. In such relatively mild temperature conditions, conventional heat-resistant mechanical transmission components, sealing materials, and motor drive systems exhibit good operational reliability, thus providing a practical engineering application basis for the multi-degree-of-freedom motion mechanism involved in this invention. This device is a comprehensive treatment system integrating mechanical motion, pneumatic assistance, and intelligent control.

[0073] In this embodiment, the core mechanical actuator of the system is an adjustment plate 2, which is made of high-temperature resistant and wear-resistant alloy steel plate. Its width is slightly smaller than the inner width of the flue to leave necessary movement clearance. The core function of the adjustment plate 2 is the controllability of its spatial posture and position. It is connected to the moving track 1 fixedly installed on the inner wall of the top of the low-temperature horizontal section flue 100 through a sliding actuator assembly. The moving track 1 is a high-strength I-beam or a special guide rail, which is firmly fixed to the inner wall of the top of the low-temperature horizontal section flue 100 by a bracket and extends along the entire length of the flue.

[0074] Traditional fixed guide vanes or soot blowers function statically and passively. In this invention, however, the horizontally movable, vertically raised, and angle-adjustable regulating plate 2, along with the remotely precisely controlled jet grille 42 with adjustable spray angle and flow rate, form a high-level spatiotemporal synergy under the command of an intelligent unit. For example, in "cruise intervention mode," when the system identifies, through a sensor network, that the flow velocity in a specific area (denoted as area A) within the flue is below a safety threshold or that fly ash deposition shows an increasing trend, its control logic reflects the precise coordination of multiple actuators in time and space. First, the intelligent control unit drives the sliding block 101 to move along the moving track 1, precisely delivering and suspending the regulating plate 2 above area A. Then, it controls the plate angle adjustment mechanism to rotate the regulating plate 2 around the horizontal axis to a calculated and optimized specific tilt angle. The core of this step lies in actively and forcibly altering the original flue gas flow structure in area A by introducing a mechanical obstacle whose position and angle are controllable, locally increasing airflow velocity and turbulence, thereby fundamentally disrupting the aerodynamic conditions for fly ash deposition. Subsequently, the intelligent unit sends commands to the angle adjustment assembly and flow control valve of the jet grille 42, causing its injection angle and flow parameters to dynamically match the current operating conditions: either adjusting the jet direction to directly supplement the disturbance to area A, or optimizing the inlet flow field to indirectly improve the upstream flow conditions of area A. This linkage control strategy of "first actively reconstructing the flow field with a movable mechanical device, and then parametrically consolidating and strengthening it with an adjustable pneumatic device" enables predictive intervention in potential ash accumulation areas; it advances the treatment action from cleaning at a fixed location after ash accumulation occurs in traditional technology to actively controlling the variable location and intensity in the early stage of the ash accumulation dynamics process, thereby realizing the transformation from passive response to predictive and targeted intervention at the source of ash accumulation.

[0075] Please see Figure 6 and Figure 7 In this embodiment, the sliding actuator assembly is the key to realizing the multi-degree-of-freedom motion of the adjustment plate 2. It includes a sliding block 101 that slides with the moving track 1, and a moving plate 102 that can be vertically slidably connected to the sliding block 101 through a linear bearing or slider structure.

[0076] In this preferred embodiment, the vertical drive mechanism is used to drive the moving plate 102 to rise and fall relative to the sliding block 101. One specific implementation includes: a toothed column 6, whose two ends are rotatably connected to the side wall or bottom of the low-temperature horizontal section flue 100 through bearing supports 701, and whose axis is parallel to the moving track 1; a first drive motor 7 (which can be a servo motor or a stepper motor) is installed outside the flue and connected to one end of the toothed column 6 through a sealed transmission shaft; on the side of the moving plate 102 facing the toothed column 6, a moving tooth 1021 that meshes with the toothed column 6 is fixedly installed; when the first drive motor 7 rotates, it drives the toothed column 6 to rotate, and through meshing with the moving tooth 1021, it can drive the moving plate 102 and all the components connected to it to rise and fall precisely in the vertical direction.

[0077] It should be noted that the gear and rack pair formed by the movable tooth 1021 and the tooth column 6 not only transmits the power for vertical lifting, but also serves as a reliable sliding guide structure. When the sliding block 101 is driven by the horizontal drive mechanism described later to move horizontally along the moving track 1, the movable tooth 1021 will slide along the axial direction of the tooth column 6 (i.e., the length direction of the rack), and will always maintain its meshing with the tooth column 6 during this process without disengaging, thereby ensuring the stability and reliability of the mechanism in compound motion.

[0078] In this embodiment, the horizontal drive mechanism and the plate angle adjustment mechanism are driven by a bidirectional motor 8. The motor is fixedly mounted on the movable plate 102, and the bidirectional motor 8 has a first output terminal 812 and a second output terminal 822 that are coaxial and rotate in opposite directions.

[0079] The plate angle adjustment mechanism includes a drive rod. One end of the drive rod is connected to the first output end 812 of the bidirectional motor 8, and the other end is connected to the side wall of the adjustment plate 2, forming a first rotating pair. When the first output end 812 of the bidirectional motor 8 rotates, the drive rod can drive the adjustment plate 2 to rotate around its hinge axis (i.e., the horizontal axis) with the lower part of the moving plate 102, thereby changing its tilt angle relative to the flue gas flow direction.

[0080] The horizontal drive mechanism is used to drive the sliding block 101 to move horizontally along the moving track 1. It includes a drive gear 9 fixedly mounted on the second output end 822 of the bidirectional motor 8; a driven gear 10 meshing with the drive gear 9 is rotatably mounted on the sliding block 101 via a rotating shaft; and a linkage mechanism 11 converts the rotational motion of the driven gear 10 into the linear motion of the sliding block 101.

[0081] Specifically, the linkage mechanism 11 includes a first linkage 1101 and a second linkage 1102. One end of the first linkage 1101 is eccentrically fixed to the side wheel surface of the driven gear 10 (i.e., the side that does not mesh with the teeth), and its other end is hinged to one end of the second linkage 1102. The other end of the second linkage 1102 is hinged to a hinge seat 1103 fixedly installed on the inner wall of the low-temperature horizontal flue 100.

[0082] Its working principle is as follows: The second output terminal 822 of the bidirectional motor 8 drives the driving gear 9 to rotate, which in turn drives the driven gear 10 to rotate. The rotation of the driven gear 10 drives the eccentrically mounted connecting rod 1101 to perform circular motion. Through the constraint and transmission of the connecting rod 1102, the circular motion is converted into the reciprocating linear motion of the sliding block 101 along the moving track 1. By controlling the rotation direction and angle of the second output terminal 822 of the bidirectional motor 8, the movement direction and stroke of the sliding block 101 can be controlled.

[0083] Please see Figure 4 and Figure 5 In this embodiment, an air blowing slot 420 is provided on the side wall of the starting end (upstream end) of the low-temperature horizontal section flue 100. An air blowing device 4 is installed here to inject high-speed airflow into the flue to disturb the accumulated ash and assist in circulation. The air blowing device 4 includes an external high-pressure air source 41 and a jet grille 42, which is densely covered with multiple nozzles. The jet grille 42 is installed in the air blowing slot 420 through an angle adjustment component, so that its injection angle can be adjusted.

[0084] In a preferred embodiment, one implementation of the angle adjustment assembly includes: a fixed rod 43, one end of which is fixedly connected to the center of the back of the jet grille 42; a fixed plate 46 fixedly mounted on the outer wall of the low-temperature horizontal section flue 100; an arc-shaped limiting block 47 fixedly connected to the middle of the fixed rod 43, with an arc-shaped slot 471 on it; a limiting post 48 fixed on the fixed plate 46 and slidably inserted into the arc-shaped slot 471 to limit the rotation trajectory; a threaded block 49 fixedly connected to the end of the fixed rod 43 away from the jet grille 42, with a threaded hole in its middle; a screw 44 screwed into the threaded hole; a support plate 410, with one end of the screw 44 rotatably connected to it via a bearing; a second drive motor 45 mounted on the support plate 410, with its output end connected to the screw 44 via a drive shaft; and one end of the support plate 410 connected to the fixed plate 46 via a rotating shaft. When the second drive motor 45 drives the screw 44 to rotate, it pushes or pulls the threaded block 49 to move axially along the screw 44, which in turn drives the jet grille 42 to rotate around the central axis of the limiting post 48 via the fixed rod 43, thus achieving stepless adjustment of the jet angle. To ensure sealing, a high-temperature resistant elastic sealing element 422 (such as a ceramic fiber woven pad) is embedded in the inner edge of the air outlet 420, and the periphery of the jet grille 42 maintains elastic contact with the sealing element 422 after installation.

[0085] To achieve precise, rapid, and stable adjustment of the jet grille 42's spray direction, the angle adjustment component in this embodiment has been specifically designed. Its core lies in the specific layout of the installation position of the limiting post 48, which constrains the rotation axis of the jet grille 42 to the area near its front spray surface. Specifically, when the second drive motor 45 drives the screw 44 to rotate, thereby pushing or pulling the threaded block 49 to move along the screw axis, the fixed rod 43 will swing around the limiting post 48 as its instantaneous rotation center. Since the limiting post 48 is connected to the back of the jet grille 42 through the fixed rod 43 and the arc-shaped limiting block 47, and its position allows the rotation of the jet grille 42 to approximately revolve around a virtual fixed point in its front spray area, thus achieving stepless adjustment of its pitch angle.

[0086] Because the rotation center is close to the front end, the lever arm of the aerodynamic reaction force on the jet grille 42 during adjustment is significantly shortened, greatly reducing the torque that the drive needs to overcome. This allows for the matching of a second drive motor 45 with lower power and faster response, which directly supports the rigid requirement of the system to quickly switch the blowing angle in the "emergency purging mode". Secondly, this rotation method makes the relative movement between the periphery of the jet grille 42 and the high-temperature resistant elastic seal 422 inside the blowing slot 420 mainly through slight compression and sliding, reducing the scratching and wear of the seal. Its long-term sealing reliability is the basis for ensuring stable blowing pressure and avoiding energy loss. Furthermore, this kinematic design makes the pitch angle change of the jet grille 42 and the rotation angle of the screw 44 present an approximately linear relationship. The adjustment of the airflow injection direction is therefore more direct and certain. This provides a reliable and predictable execution interface for the intelligent control unit to calculate and set the "optimal dust removal angle" according to real-time working conditions (such as the location of the blockage area).

[0087] In this preferred embodiment, to prevent fly ash from entering the precision fit gap between the moving track 1 and the sliding block 101 and causing jamming, an air curtain generating device 5 is provided on the side of the moving track 1. This device includes an air curtain nozzle 51 laid along the length of the moving track 1, with a row of air curtain nozzles 52 facing the gap between the sliding block 101 and the inner wall of the flue. The air curtain nozzle 51 is connected to a high-pressure air source through a high-temperature resistant flexible pipeline and is equipped with an independent control valve.

[0088] The ash collection trough 3 is located at one end of the bottom of the low-temperature horizontal section flue 100; in order to further process the collected fly ash, the bottom of the ash collection trough 3 is provided with an ash discharge port, which is connected to the power plant's pneumatic ash conveying system or mechanical ash conveying system through a pipeline to realize the continuous discharge of collected fly ash.

[0089] The entire device is controlled by an intelligent control unit, which can be a PLC or DCS controller. The intelligent control unit is electrically connected to the first drive motor 7, the bidirectional motor 8, the second drive motor 45, the air supply valve of the high-pressure air source 41, and the control valve of the air curtain generator 5 via signal lines. Simultaneously, the intelligent control unit also receives sensor signals from multiple key locations within the flue, including but not limited to: differential pressure transmitters for monitoring pressure differences before and after the flue and in different areas; thermal or ultrasonic flow meters for monitoring local flue gas velocity; and radar or laser rangefinders (not shown in the figure) for monitoring fly ash deposition thickness. These sensors provide real-time operating parameters for the system. The selection and installation methods of the aforementioned sensors, as well as the hardware configuration and control logic implementation principle of the intelligent control unit (such as a PLC / DCS), are mature existing technologies in the field of industrial automation and are not the focus of improvement in this technical solution; therefore, they will not be elaborated upon here.

[0090] The working process and method of the device of the present invention are as follows:

[0091] The intelligent control unit continuously collects and analyzes signals of pressure difference distribution, flow velocity distribution, and fly ash deposition thickness distribution in the flue. By comparing and analyzing these signals with a preset threshold model (which is established based on unit load, coal quality, historical operating data, etc.), the decision-making system enters the corresponding working mode.

[0092] 1. Cruise intervention mode:

[0093] When monitoring and analysis detect that the flow velocity in a certain area of ​​the flue gas duct remains below a set threshold, or that the fly ash deposition thickness shows a slow but stable growth trend, but has not yet reached the point where immediate full mechanical cleaning is required, the system enters a cruise intervention mode. The intelligent control unit first controls the sliding block 101 to move along the moving track 1 to above the target area, and then controls the plate angle adjustment mechanism to drive the adjustment plate 2 to rotate to a preset tilt angle (e.g., 30°-60°) suitable for local flow field adjustment. This posture causes the adjustment plate 2 to partially throttle the flue gas, change the local flow field structure, and enhance the airflow's ability to scour the bottom ash layer, thereby inhibiting further deposition.

[0094] Simultaneously, based on the position of the target area relative to the flue inlet, the intelligent control unit can control the jet grille 42 to adjust its jet angle to a specific auxiliary angle (i.e., the first angle) and jet at a moderate flow rate (i.e., the first flow rate). The purpose is either to form a stable wall-adhering air cushion in the flue inlet area, improving overall air intake conditions, or to enhance the directional airflow in the target ash accumulation risk area, achieving aerodynamic assisted disturbance. In this mode, the air curtain generating device 5 operates at a relatively low constant pressure (i.e., the first pressure), forming a basic protective air curtain.

[0095] As an additional continuous cleaning strategy, if the system determines that continuous intervention or preventative cleaning of a longer section is required, the intelligent control unit can activate the automatic reciprocating function of the horizontal drive mechanism. Specifically, the bidirectional motor 8 is controlled to run continuously, and through the meshing transmission of the driving gear 9 and the driven gear 10, and through the conversion of the linkage mechanism 11, the sliding block 101 and its connected adjusting plate 2 are driven to move continuously and stably along the moving track 1 in a horizontal reciprocating manner. During this process, the tilt angle of the adjusting plate 2 can be maintained at a set value or dynamically fine-tuned, thereby realizing continuous "sweeping" flow field optimization and deposition prevention in the bottom area of ​​a section of flue.

[0096] 2. Planned dust removal mode:

[0097] According to a preset timing strategy, or when the overall ash thickness at the bottom of the flue reaches the cleaning threshold, the system enters this mode. The intelligent control unit first controls the adjustment plate 2 to rotate to a "cleaning angle" nearly parallel to the bottom of the flue (e.g., an angle of 5°-15° with the bottom surface), and then lowers it via a vertical drive mechanism until its lower edge slightly touches or is very close to the bottom of the flue. Next, the control slider 101 moves slowly along the moving track 1 from one end of the flue to the ash collection trough 3 at the other end, and the adjustment plate 2 scrapes and pushes the bottom ash like a scraper. After reaching the endpoint, the adjustment plate 2 can be slightly raised, and the slider 101 returns, or the next scraping stroke begins. During the cleaning process, the jet grille 42 can provide auxiliary jetting to help lift the loosened fly ash and transport it towards the ash collection trough 3. In this mode, to prevent a large amount of scraped fly ash from entering the track gap, the air curtain generator 5 increases the air supply pressure to a second pressure (higher than the first pressure during cruising), forming a stronger sealing air curtain.

[0098] 3. Emergency purging mode:

[0099] When the differential pressure signal at a certain point in the flue rises sharply, indicating a possible severe local blockage or ash collapse, the system immediately switches to emergency purging mode. The intelligent control unit quickly locates the blockage area based on the sudden change in differential pressure signal and generates the primary control command: controls the jet grille 42 to switch to the maximum air supply flow, and simultaneously drives the angle adjustment component through the second drive motor 45 to quickly adjust the jet grille 42 to the optimal ash removal angle for the blockage area. For example, this angle can be adjusted so that the direction of its jet airflow is approximately parallel to the surface of the blockage or the flue wall to generate maximum shear force, achieving high-intensity, directional pneumatic purging of the blockage or caking ash layer, thereby quickly clearing the blockage.

[0100] Meanwhile, to prevent mechanical components from being damaged or obstructing airflow in a strong airflow environment, the intelligent control unit synchronously controls the vertical drive mechanism to quickly raise the adjustment plate 2 to a safe height, and controls the plate angle adjustment mechanism to rotate it to a clearance position parallel to the main flue gas flow direction; the air curtain generating device 5 maintains or enhances the air curtain output in this mode to ensure the sealing and protection around the moving parts of the sliding actuator assembly. After the flue pressure differential signal returns to the normal range, the system can automatically exit the emergency mode and switch back to the cruise intervention mode or the planned ash cleaning mode according to the overall strategy.

[0101] Through the above-mentioned collaborative working method, the device of the present invention realizes intelligent prediction, active intervention, online cleaning and emergency treatment of fly ash deposition in flue gas, forming a complete closed-loop treatment system.

[0102] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A fly ash throttling and enhanced collection device for a boiler tail flue, installed in the low-temperature horizontal section of the boiler tail flue (100), characterized in that, include: The moving track (1) is fixedly installed on the bottom inner wall of the low-temperature horizontal section flue (100) and extends along the length of the flue; The sliding actuator assembly is movably mounted on the moving track (1); The functional actuator is an adjustment plate (2) connected to the sliding actuator assembly. The adjustment plate (2) is configured to change its spatial attitude and position in the flue under the drive of the sliding actuator assembly, so as to selectively perform active throttling of the flue gas flow or mechanical scraping of the ash accumulated on the bottom wall of the flue. Ash collection trough (3) is provided at one end of the bottom of the low temperature horizontal section flue (100); The sliding execution assembly includes: The sliding block (101) is in sliding engagement with the moving track (1); The movable plate (102) is slidably connected to the sliding block (101) in the vertical direction. A vertical drive mechanism is used to drive the movable plate (102) to move up and down relative to the sliding block (101); A horizontal drive mechanism is used to drive the sliding block (101) to move horizontally along the moving track (1); A plate angle adjustment mechanism is used to drive the adjustment plate (2) to rotate about a horizontal axis relative to the moving plate (102); An air blowing slot (420) is provided on the side wall at the starting end of the low-temperature horizontal section flue (100), and an air blowing device (4) is installed at the air blowing slot (420) for injecting airflow into the flue. The side of the moving track (1) is provided with an air curtain generating device (5) for spraying gas into the gap between the sliding block (101) and the inner wall of the flue to form an air curtain.

2. The fly ash throttling and enhanced collection device for boiler tail flue as described in claim 1, characterized in that, The vertical drive mechanism includes: The toothed column (6) is parallel to the moving track (1) in its length direction, and its two ends are rotatably connected to the bottom or side wall of the low temperature horizontal section flue (100) through bearing supports (701). The first drive motor (7) has its output end connected to one end of the gear column (6); The movable plate (102) has movable teeth (1021) on the side facing the toothed column (6) that mesh with the toothed column (6).

3. The fly ash throttling and enhanced collection device for boiler tail flue as described in claim 1, characterized in that, The horizontal drive mechanism and the plate angle adjustment mechanism are driven by a bidirectional motor (8); The bidirectional motor (8) is fixedly installed on the movable plate (102), and has a first output end (812) and a second output end (822) that are coaxial and output in opposite directions. The plate angle adjustment mechanism includes a drive rod, one end of which is connected to the first output end (812) of the bidirectional motor (8), and the other end is hinged to the adjustment plate (2), forming a first rotating pair that drives the adjustment plate (2) to rotate. The horizontal drive mechanism includes: The drive gear (9) is fixedly mounted on the second output end (822) of the bidirectional motor (8); The driven gear (10) meshes with the driving gear (9) and is rotatably mounted on the sliding block (101) via a rotating shaft; The linkage mechanism (11) has its first end connected to the side wheel surface of the driven gear (10) and its second end hinged to the fixed structure of the moving track (1) or the low-temperature horizontal section flue (100). The rotational motion of the driven gear (10) is converted into the reciprocating linear motion of the sliding block (101) along the moving track (1) by the linkage mechanism (11).

4. A fly ash throttling and enhanced collection device for boiler tail flue according to claim 3, characterized in that, The linkage mechanism (11) includes a first link (1101) and a second link (1102). One end of the first connecting rod (1101) is fixedly connected to the side wheel surface of the driven gear (10), and the other end is hinged to one end of the second connecting rod (1102). The other end of the connecting rod (1102) is hinged to a hinge seat fixedly installed on the inner wall of the low-temperature horizontal flue (100).

5. A fly ash throttling and enhanced collection device for boiler tail flue according to claim 1, characterized in that, The blowing device (4) includes a high-pressure air source (41) and a jet grille (42). The jet grille (42) is installed in the air inlet (420) via an angle adjustment assembly; The inner edge of the air-blowing slot (420) is provided with a high-temperature resistant elastic seal (422), and the periphery of the jet grille (42) is in elastic contact with the seal (422) to achieve a seal.

6. A fly ash throttling and enhanced collection device for boiler tail flue according to claim 5, characterized in that, The angle adjustment component includes: A fixing rod (43) is fixedly connected at one end to the back of the jet grille (42); A fixing plate (46) is fixed to the outer wall of the low-temperature horizontal section flue (100); An arc-shaped limiting block (47) is fixedly connected to the middle part of the fixing rod (43), and an arc-shaped groove (471) is provided on it. The limiting post (48) is fixed on the fixing plate (46) and slides through the arc-shaped groove (471); A threaded block (49) is fixedly connected to one end of the fixed rod (43) away from the jet grille (42), and has a threaded hole in its middle; The screw (44) engages with the threaded hole of the threaded block (49); Support plate (410), one end of the screw (44) is rotatably connected to the support plate (410) via a bearing; The second drive motor (45) is mounted on the support plate (410), and its output end is connected to the screw (44) for transmission. One end of the support plate (410) is rotatably connected to the fixed plate (46); the rotation of the screw (44) drives the threaded block (49) to move along its axial direction, and then drives the jet grille (42) to rotate around the central axis of the limiting post (48) through the fixed rod (43).

7. A fly ash throttling and enhanced collection device for boiler tail flue according to claim 5, characterized in that, The air curtain generating device (5) includes an air curtain nozzle (51) arranged along the length of the moving track (1), and the air curtain nozzle (51) is provided with a plurality of air curtain nozzles (52) facing the gap between the sliding block (101) and the inner wall of the flue; the air curtain nozzle (51) is connected to a high-pressure gas source (41) through a flexible pipeline.

8. A fly ash throttling and enhanced collection device for boiler tail flue according to claim 1, characterized in that, It also includes an intelligent control unit, which is electrically connected to the control valves of the first drive motor (7), the bidirectional motor (8), the second drive motor (45), the high-pressure air source (41), and the air curtain generator (5).

9. A method for using a fly ash throttling and enhanced collection device for a boiler tail flue as described in any one of claims 1-8, characterized in that, The method includes: Real-time acquisition of operating parameters within the flue, including differential pressure distribution signals, flow velocity distribution signals, and fly ash deposition thickness distribution signals in different regions of the flue. Based on the comparison and analysis of the operating parameters and preset thresholds, a decision is made to enter the corresponding working mode; the working modes include cruise intervention mode, planned dust removal mode and emergency purging mode; If the decision is to enter the cruise intervention mode, then the first cooperative control strategy will be executed: Based on the real-time acquired signals of differential pressure distribution, flow velocity distribution, and fly ash deposition thickness distribution, target areas requiring intervention within the flue are identified. These target areas include areas with abnormal flow fields and areas at risk of ash accumulation. Control the sliding block (101) to move along the moving track (1) to the target area; The plate angle adjustment mechanism is controlled to adjust the tilt angle of the adjustment plate (2) in order to optimize the flow field in the target area; Meanwhile, depending on the type of the target area, the jet grille (42) is controlled to inject airflow into the flue with a corresponding flow rate and angle; wherein, when the target area is an area with abnormal flow field, the jet grille (42) is controlled to inject with a first flow rate and a first angle to form a wall-adhering air cushion in the flue inlet area; when the target area is an area with ash accumulation risk, the injection angle of the jet grille (42) is adjusted to strengthen the airflow in the area with ash accumulation risk. Control the air curtain generating device (5) to operate at a first pressure; If the decision enters the planned dust removal mode, then the second collaborative control strategy is executed: Control the adjustment plate (2) to rotate to the cleaning angle and lower it to contact the bottom of the flue; At the same time, the sliding block (101) is controlled to move horizontally back and forth along the moving track (1) to continuously scrape the ash at the bottom of the flue to the ash collection trough (3). During the dust removal process, the jet grille (42) is controlled to perform auxiliary jetting, and its jetting angle can be adjusted as needed to assist in the conveying of fly ash; In this mode, the air curtain generating device (5) is controlled to operate at a second pressure higher than the first pressure; If the decision is to enter the emergency purging mode, then the third collaborative control strategy will be executed: The blockage area is located based on the rapidly increasing differential pressure signal; Control the jet grille (42) to blow powerfully at maximum flow and adjust it to the optimal cleaning angle for the clogged area; At the same time, the adjustment plate (2) is raised and rotated to the avoidance position, and the air curtain generating device (5) is controlled to maintain or enhance the air curtain.

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