A boiler air preheater preventing condensation and dust accumulation

Abstract

The utility model discloses a prevent condensation boiler air preheater of ash deposit, including box, cleaning assembly and elevating traction device, be equipped with the heat pipe in the box, cleaning assembly swing is equipped in the box, including cleaning plate and draw bar, is equipped with the material scraping structure of sheathed in the heat pipe outside on the cleaning plate, and draw bar is connected with cleaning plate and swing penetrates the box, elevating traction device is equipped with the outside of box, and is driven cleaning assembly along the heat pipe with draw bar cooperation to remove, aiming at the problem that the condensate water mixes with fly ash and forms the sticky ash deposit that is difficult to remove, and the device realizes active cleaning through the cooperation of cleaning assembly and elevating traction device, and the material scraping ring on the cleaning plate is closely sheathed in the heat pipe outside, when elevating traction device drives draw bar and drives cleaning plate to move up and down along the heat pipe, the material scraping ring can scrape off the sticky ash deposit on the outer wall of heat pipe completely, avoids the ash deposit and blocks the ventilation gap.

Description

Technical Field

[0001] This utility model relates to the technical field of industrial boiler heat exchange equipment, and more specifically, to a boiler air preheater that prevents condensation and ash accumulation. Background Technology

[0002] In industrial boiler operating systems, the air preheater, as a core heat exchange device, primarily functions to utilize the waste heat of the flue gas at the boiler's tail end to heat the cold air entering the boiler, thereby improving boiler combustion efficiency and reducing exhaust heat loss. It is a key device for achieving energy-saving boiler operation. Among them, the tubular air preheater, with heat-conducting tubes as the core heat exchange element, is widely used in various industrial boiler systems due to its stable structure and high heat exchange efficiency.

[0003] However, in actual industrial production scenarios, tubular air preheaters generally face the problem of ash accumulation caused by condensate precipitation, especially in northern winters or under high humidity conditions. This problem is more prominent and has become a major bottleneck restricting the stable and efficient operation of boilers. Specifically, when the boiler inlet air temperature is low, the cold air flows through the heat-conducting tubes of the air preheater and exchanges heat with the high-temperature flue gas inside the tubes, causing the temperature of the outer wall of the heat-conducting tubes to drop rapidly. When the temperature of the outer wall of the heat-conducting tubes is lower than the dew point temperature of the flue gas, water vapor in the flue gas will condense on the outer wall of the heat-conducting tubes to form condensate.

[0004] This condensate mixes with impurities such as fly ash and unburned carbon particles carried in the flue gas, forming a sticky ash layer on the outer wall of the heat pipes. This ash layer not only blocks the ventilation gaps between the heat pipes, increasing airflow resistance and resulting in insufficient air intake, thus affecting the completeness of boiler combustion and causing a decrease in boiler output efficiency, but more seriously, the sticky ash adheres firmly to the surface of the heat pipes and is difficult to remove with conventional soot blowing devices. To prevent further deterioration of the ash accumulation and heat exchange failure, companies have to frequently shut down the boiler for manual cleaning. Each shutdown for cleaning is not only time-consuming but also incurs high labor costs and equipment downtime losses. At the same time, frequent disassembly and cleaning will also accelerate the wear and corrosion of the heat pipes, shortening the service life of the air preheater.

[0005] Existing solutions for ash accumulation in air preheaters, such as steam soot blowing and sonic soot blowing, are all "passive cleaning" methods. They are only effective for loose ash and have limited effectiveness for sticky ash caused by condensation. Some companies have tried to prevent condensation by increasing the inlet air temperature, but this requires additional preheating devices, leading to a significant increase in equipment investment and energy consumption, making it uneconomical. Therefore, developing an air preheater that can actively prevent and efficiently clean condensed sticky ash without additional energy consumption and is suitable for the high-temperature operating conditions of boilers has become an urgent technical need in the current industrial boiler field. Utility Model Content

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A boiler air preheater for preventing condensation and ash accumulation includes a housing, a cleaning assembly, and a lifting and traction device. The housing is equipped with a heat-conducting pipe, and the housing has an air inlet and an air outlet communicating with the heat-conducting pipe, as well as a heating inlet and a heating outlet for introducing heating air. The cleaning assembly is movably disposed within the housing and includes a cleaning plate and a traction rod. The cleaning plate has a scraping structure sleeved on the outside of the heat-conducting pipe. The traction rod is connected to the cleaning plate and movably passes through the housing. The lifting and traction device is disposed on the outside of the housing and cooperates with the traction rod to drive the cleaning assembly to move along the heat-conducting pipe.

[0008] Furthermore, the box has a top plate at the top and a bottom plate at the bottom, heat pipes are equidistantly arranged between the top and bottom plates, an air inlet is located on both sides of the top of the box, and an air outlet is located on one side of the bottom of the box.

[0009] Furthermore, the scraping structure of the cleaning component is a scraping ring, which is equidistantly arranged inside the cleaning plate, and the traction rod is installed on the top of the cleaning plate and passes through the top of the box.

[0010] Furthermore, a gantry frame is installed on the top of the box, and two sets of lifting and traction devices are installed inside the gantry frame.

[0011] Furthermore, the lifting and traction device includes a box and a slider. Two sets of sliders are movably installed inside the box, and a traction wheel for clamping the traction rod is installed on one side of the slider extending outside the box.

[0012] Furthermore, an elastic element is provided on the inner side of the slider, one end of which is connected to the inner wall of the box, and the elastic element is a compression spring.

[0013] Furthermore, a guide rail is installed on the front of the box, and the slider is slidably connected to the guide rail.

[0014] Furthermore, the traction wheel is electrically driven, and its outer wall is provided with anti-slip textures that fit the surface of the traction rod.

[0015] Furthermore, the scraper ring is made of high-temperature resistant alloy material, and its inner wall is wrapped with a graphite sealing layer, which is tightly attached to the outer wall of the heat pipe.

[0016] Furthermore, the two sets of lifting traction devices are electrically connected through a synchronization controller, which controls the rotation speed and direction of the two sets of traction wheels to be consistent.

[0017] In summary, this utility model has the following beneficial technical effects:

[0018] 1. To address the problem of difficult-to-remove sticky ash formed by the mixture of condensate and fly ash, this device achieves active cleaning through the coordinated action of the cleaning components and the lifting and traction device. The scraper ring on the cleaning plate is tightly fitted to the outside of the heat conduction pipe. When the lifting and traction device drives the traction rod to move the cleaning plate up and down along the heat conduction pipe, the scraper ring can completely scrape off the sticky ash on the outer wall of the heat conduction pipe, preventing the ash from blocking the ventilation gap.

[0019] 2. The lifting and traction device of this unit is installed on the top of the box through a gantry frame. The overall structure is compact and does not require major modifications to the main structure of the existing boiler air preheater. It can be adapted to different specifications of equipment simply by adjusting the spacing of the scraper rings on the cleaning plate according to the layout of the heat pipes. It has strong adaptability. At the same time, the constant clamping force provided by the elastic element and the guiding effect of the guide rail on the slider ensure the stable cooperation between the traction wheel and the traction rod, avoid the displacement of the cleaning components caused by boiler operation vibration, and ensure the reliability of continuous operation of the equipment. Attached Figure Description

[0020] The disclosure of this utility model is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. In the drawings, the same reference numerals are used to refer to the same parts.

[0021] in:

[0022] Figure 1 This is a three-dimensional schematic diagram of the present invention;

[0023] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0024] Figure 3 This is a schematic diagram of the rear structure of this utility model;

[0025] Figure 4 This is a schematic diagram of the interior of the box body of this utility model;

[0026] Figure 5 This is a schematic diagram of the guide rail structure of this utility model;

[0027] Figure 6 This is a schematic diagram of the cleaning component structure of this utility model;

[0028] Figure 7 This is a schematic diagram of the scraper ring structure of this utility model.

[0029] Figures 1-7Explanation of reference numerals in the attached drawings: 1. Box body; 101. Air inlet; 102. Air outlet; 103. Top plate; 104. Bottom plate; 105. Heat pipe; 2. Gantry frame; 3. Lifting and traction device; 301. Box body; 302. Slider; 303. Traction wheel; 304. Elastic element; 305. Guide rail; 4. Heating inlet; 5. Cleaning assembly; 501. Traction rod; 502. Cleaning plate; 503. Scraper ring; 6. Heating outlet. Detailed Implementation

[0030] Based on the technical solution of this utility model, without changing the essential spirit of this utility model, those skilled in the art can propose various interchangeable structural methods and implementation methods. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative descriptions of the technical solution of this utility model, and should not be regarded as the entirety of this utility model or as a limitation or restriction of the technical solution of this utility model.

[0031] The following is in conjunction with the attached diagram ( Figures 1-7 The present invention will be further described in detail with reference to specific embodiments, but is not limited to the following embodiments:

[0032] Example 1:

[0033] like Figures 1-7 As shown, a boiler air preheater for preventing condensation and ash accumulation includes a housing 1, a cleaning assembly 5, and a lifting and traction device 3. Circular air inlets 101 are symmetrically opened on both sides of the top of the housing 1, and a rectangular air outlet 102 is opened on one side of the bottom. A flange-type heating inlet 4 is welded on the front, and a flange-type heating outlet 6 is welded on the back. Both the heating inlet 4 and the heating outlet 6 are connected to the inner cavity of the housing to form a boiler flue gas circulation channel.

[0034] A steel top plate 103 is welded to the upper part of the interior of the housing 1, and a steel bottom plate 104 is welded to the lower part of the interior. Heat-conducting pipes 105 are welded through the top plate 103 and the bottom plate 104 at equal intervals. The ends are sealed and welded to the top plate 103 and the bottom plate 104 respectively to ensure that the flue gas only flows inside the heat-conducting pipes 105. The air inlet 101 is connected to the heat-conducting pipes 105 through the diversion cavity on the top plate 103, and the air outlet 102 is connected to the heat-conducting pipes 105 through the confluence cavity on the bottom plate 104, forming a cold air heat exchange channel.

[0035] The cleaning component 5 is movably installed inside the housing 1 and includes a traction rod 501, a cleaning plate 502, and a scraper ring 503. The cleaning plate 502 is a steel plate with a length and width that fit the inner cavity of the housing 1. Multiple mounting holes are equidistantly opened along the axis of the cleaning plate 502. Each mounting hole is interference-fitted with a scraper ring 503. The scraper ring 503 uses a high-temperature resistant alloy as its base and a flexible graphite sealing layer is bonded to its inner wall. The inner diameter of the graphite sealing layer is consistent with the outer diameter of the heat conduction pipe 105, and the cross-section is an isosceles trapezoid, ensuring a tight fit with the outer wall of the heat conduction pipe 105 and uniform scraping resistance. The traction rod 501 is a solid steel rod with its bottom fixedly connected to the center of the cleaning plate 502 and its top movably passing through the sealing guide sleeve at the top of the housing 1, extending to the outside of the housing 1.

[0036] The top of the box 1 is fixed with a gantry frame 2 by bolts. The gantry frame 2 is a steel frame structure, and two sets of lifting and traction devices 3 are symmetrically installed inside. The center line of the two sets of devices coincides with the axis of the traction rod 501 to ensure balanced traction force.

[0037] Example 2:

[0038] like Figure 4 and Figure 5 As shown, the lifting traction device 3 includes a housing 301, a slider 302, a traction wheel 303, an elastic element 304, and a guide rail 305, with the specific structure as follows:

[0039] The box body 301 is a rectangular steel box, which is fixed to the bottom of the crossbeam of the gantry frame 2 by bolts. Two sliding cavities are symmetrically opened inside the box body 301. A slider 302 is movably installed in each sliding cavity. The slider 302 extends to the front side of the box body 301 and is rotatably mounted with a traction wheel 303 through a bearing. The traction wheel 303 is a rubber-coated wheel with anti-slip texture on the wheel surface. The two sets of traction wheels 303 are arranged opposite each other, and the distance between the wheel surfaces is adapted to the diameter of the traction rod 501, and together they clamp the traction rod 501.

[0040] A positioning post is welded to one side of the slider 302 inside the box 301. An elastic element 304 is fitted on the positioning post. The elastic element 304 is a compression spring. One end of the spring is in contact with the end face of the slider 302, and the other end is in contact with the baffle welded to the inner wall of the box 301. The spring force keeps the two sets of traction wheels 303 clamping the traction rod 501. A guide rail 305 is fixedly installed on the front of the box 301 by bolts. The guide rail 305 is a rectangular steel guide rail. The protrusion on the front of the slider 302 slides in contact with the groove of the guide rail 305, restricting the slider 302 to move only in the horizontal direction.

[0041] The axle of the traction wheel 303 is connected to the micro gear motor (not shown in the figure) via a coupling and is fixedly installed inside the slider 302. The gear motors of the two sets of lifting traction devices 3 are electrically connected to the external synchronous controller, which can control the speed and direction of the two sets of traction wheels 303 to be completely consistent, so as to avoid the traction rod 501 being deviated by force.

[0042] The core of this device is to achieve heat exchange between air and boiler hot gas through dual independent flow channels. Condensate and ash accumulation arise from the temperature difference between the two flow channels and the contact between the media. The specific flow path and ash formation logic are as follows:

[0043] Boiler hot gas circulation path (high temperature side): The high temperature flue gas generated by combustion at the tail end of the boiler enters the "flue gas chamber" of the box 1 through the flange-connected heating inlet 4, which is the space inside the box and outside the heat-conducting pipe. It diffuses evenly along the flue gas chamber, flows through the outer wall of each heat-conducting pipe 105, and exchanges heat with the heat-conducting pipe. After the temperature drops to low temperature flue gas, it is discharged from the heating outlet 6 on the back of the box and enters the subsequent desulfurization and denitrification system. Heated air circulation path (low temperature side): The ambient temperature cold air enters the diversion chamber of the top plate 103 through the air inlet 101 at the top of the box and is diverted to the internal channel of each heat-conducting pipe 105. It flows downward along the inner wall of the heat-conducting pipe and exchanges heat with the high temperature flue gas on the outer wall of the pipe. It is heated and collected in the confluence chamber of the bottom plate and discharged from the air outlet 102. It enters the boiler furnace to assist combustion. During this process, the outside of the heat-conducting pipe 105 will have sticky ash due to the flue gas cooling and the adhesion of fly ash by condensate.

[0044] This device targets the sticky ash deposits formed by flue gas cooling and condensation adhering to fly ash. It achieves online removal via a lifting and traction device 3 driving a cleaning assembly 5. After the synchronous controller is activated, the electrically driven traction wheels 303 of the two lifting and traction devices 3 rotate synchronously. Through the friction between the wheel surface and the traction rod 501, the traction rod moves smoothly vertically. The constant clamping force provided by the elastic element 304 ensures a tight fit between the traction wheel and the traction rod, preventing slippage. The traction rod 501 drives the cleaning plate 502 to move up and down along the axis of the heat-conducting pipe 105. The scraping ring 503 on the cleaning plate makes close contact with the outer wall of the heat-conducting pipe 105, thoroughly scraping away the sticky ash deposits formed by the mixture of condensation and fly ash. The ash falls into the ash collection hopper at the bottom of the housing and is discharged with the air.

[0045] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0046] Secondly: The accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0047] Finally: The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

[0048] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A boiler air preheater that prevents condensation and ash accumulation, characterized in that, Includes a housing (1), a cleaning assembly (5), and a lifting and traction device (3); The box (1) is provided with a heat-conducting pipe (105), and the box (1) is provided with an air inlet (101) and an air outlet (102) connected to the heat-conducting pipe (105), as well as a heating inlet (4) and a heating outlet (6) for introducing heating. The cleaning component (5) is movably disposed inside the housing (1) and includes a cleaning plate (502) and a traction rod (501). The cleaning plate (502) is provided with a scraping structure sleeved on the outside of the heat-conducting pipe (105). The traction rod (501) is connected to the cleaning plate (502) and movably passes through the housing (1). The lifting and traction device (3) is located on the outside of the box (1) and works with the traction rod (501) to drive the cleaning assembly (5) to move along the heat pipe (105).

2. The boiler air preheater for preventing condensation and ash accumulation according to claim 1, characterized in that: The box (1) has a top plate (103) on the upper part and a bottom plate (104) on the lower part. Heat pipes (105) are equidistantly arranged between the top plate (103) and the bottom plate (104). Air inlets (101) are located on both sides of the top of the box (1) and air outlets (102) are located on one side of the bottom of the box (1).

3. The boiler air preheater for preventing condensation and ash accumulation according to claim 1, characterized in that: The scraping structure of the cleaning component (5) is a scraping ring (503), which is equidistantly arranged inside the cleaning plate (502). The traction rod (501) is installed on the top of the cleaning plate (502) and passes through the top of the box (1).

4. The boiler air preheater for preventing condensation and ash accumulation according to claim 1, characterized in that: The top of the box (1) is equipped with a gantry frame (2), and the lifting and traction device (3) consists of two sets and is installed inside the gantry frame (2).

5. The boiler air preheater for preventing condensation and ash accumulation according to claim 4, characterized in that: The lifting traction device (3) includes a box (301) and a slider (302). Two sets of sliders (302) are movably installed inside the box (301). A traction wheel (303) for clamping the traction rod (501) is installed on one side of the slider (302) extending outside the box (301).

6. The boiler air preheater for preventing condensation and ash accumulation according to claim 5, characterized in that: The slider (302) is provided with an elastic element (304) on its inner side. One end of the elastic element (304) is connected to the inner wall of the box (301). The elastic element (304) is a compression spring.

7. The boiler air preheater for preventing condensation and ash accumulation according to claim 5, characterized in that: The box body (301) is equipped with a guide rail (305) on the front, and the slider (302) is slidably connected to the guide rail (305).

8. The boiler air preheater for preventing condensation and ash accumulation according to claim 5, characterized in that: The traction wheel (303) is electrically driven, and its outer side wall is provided with anti-slip texture that fits the surface of the traction rod (501).

9. The boiler air preheater for preventing condensation and ash accumulation according to claim 3, characterized in that: The scraper ring (503) is made of high-temperature resistant alloy material, and its inner wall is wrapped with a graphite sealing layer. The graphite sealing layer is tightly attached to the outer wall of the heat pipe (105).

10. The boiler air preheater for preventing condensation and ash accumulation according to claim 1 or 8, characterized in that: The two sets of lifting traction devices (3) are electrically connected through a synchronous controller, which controls the rotation speed and direction of the two sets of traction wheels (303) to be consistent.

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