Ash removal structure of pneumatic conveying device of thermal power plant

Abstract

The utility model discloses an ash removal structure of a pneumatic conveying device of a thermal power plant, which relates to the technical field of pneumatic ash conveying and comprises an ash removal unit arranged on the inner side of an ash conveying pipeline, the ash removal unit comprises a rotating part and a threaded screw rod, the threaded screw rod is fixedly mounted on the inner side of the ash conveying pipeline, and the rotating part comprises a threaded sleeve, a rotary vane and an ash removal ring. The outer side of the threaded lead screw is sleeved with the threaded sleeve in a threaded mode, the outer wall of the ash removal ring is attached to the inner wall of the ash conveying pipeline in a sliding mode, through matched arrangement of the threaded sleeve, the rotary blades, the ash removal ring and the threaded lead screw, in the process that airflow drives materials to flow towards the ash silo, the rotary blades are driven to rotate, and the rotary blades drive the threaded sleeve to rotate; the threaded sleeve rotates and reciprocates in the length direction of the threaded lead screw at the same time, so that the dust removing ring is driven to remove dust attached to the inner wall of the dust conveying pipeline, only one dust removing unit needs to be arranged on the inner side of the dust conveying pipeline, material conveying resistance is greatly reduced, and the dust removing effect is better.

Description

Technical Field

[0001] The utility model relates to the technical field of pneumatic ash conveying, in particular to an ash removal structure of a pneumatic conveying device in a thermal power plant. Background Art

[0002] Pneumatic conveying, also known as air flow conveying, uses the energy of air flow to transport granular materials along the direction of air flow in a closed pipe. It is a specific application of fluidization technology.

[0003] At present, the ash removal system of coal-fired power plants generally adopts positive pressure pneumatic conveying system and double-tube conveying technology. Since the actual coal type used in the power plant is different from the designed coal type, the ash content of the coal increases, resulting in an increase in boiler ash discharge. The output of the original ash removal system cannot meet the conveying requirements, and the gas consumption for conveying increases, thereby increasing the energy consumption of the air compressor. Taking a power plant in Tianjin as an example, the ash removal system is a positive pressure pneumatic conveying system with a maximum output of 61.7t / h and 6 air compressors (42m3 / min) running at the same time. The ash content of the actual coal used by the power plant is much higher than the designed ash content, and the dry ash removal system has reached or even been operating at the critical load of the system design for a long time.

[0004] In addition, the pneumatic conveying system has a high gas-to-solid ratio and a low material flow rate. Under the influence of gravity, the gas-solid mixture forms a state in the conveying pipe where there is more gas and less solid in the upper part of the pipe, and more solid and less gas in the lower part. The air flow speed in the upper part is fast, and the air flow speed in the lower part is slow. This makes it easy for coal powder to deposit at the bottom of the conveying pipe, causing the pipe cross-section to gradually decrease, and finally causing pipe blockage, which is more likely to occur in conveying pipes with long conveying distances and large pipe diameters.

[0005] In order to improve the above problems, after searching, for example, a pneumatic conveying device for ash removal in a thermal power plant is provided with patent application number 202322235614.5, which involves the field of pneumatic ash conveying technology. An accompanying air pipeline is arranged along the length direction of the ash conveying pipeline, and a plurality of pilot automatic plug valves are installed equidistantly between the accompanying air pipeline and the ash conveying pipeline. The accompanying air pipeline is used to provide an air source for the pneumatic conveyor to maintain a normal ash conveying pressure, so that the material is always in a suspended state and the amount of material deposition is reduced. By installing a plurality of ash cleaning structures equidistantly on the inner side of the ash conveying pipeline, the airflow carries the material toward the ash bin, driving the rotor blades to rotate. The rotor blades rotate against the inner wall of the ash conveying pipeline with a plurality of cleaning rods through the mounting ring to remove a small amount of material deposited on the inner side of the ash conveying pipeline, maintain the smoothness of the ash conveying pipeline, ensure the stability of ash conveying, and do not require manual cleaning, thus saving labor.

[0006] Based on the above search and in combination with the prior art, it is found that the pneumatic conveying device similar to the above disclosure in the prior art needs to install multiple ash cleaning structures at equal distances on the inner side of the ash conveying pipeline. The multiple ash cleaning structures will hinder the conveying of the carried materials to a certain extent, reducing the conveying speed of the materials. Therefore, a ash removal structure of a pneumatic conveying device for a thermal power plant is proposed to improve the above problem. Utility Model Content

[0007] The purpose of the present application is to provide an ash removal structure for a pneumatic conveying device of a thermal power plant to solve the problems raised in the above-mentioned background technology.

[0008] To achieve the above-mentioned purpose, the present application provides the following technical solutions: an ash removal structure of a pneumatic conveying device of a thermal power plant, comprising an ash removal unit arranged inside an ash conveying pipeline, and the ash removal unit is located inside a straight pipe section of the ash conveying pipeline;

[0009] The ash removal unit includes a rotating portion and a threaded screw;

[0010] The threaded screw is fixedly installed on the inner side of the ash conveying pipeline and is arranged coaxially with the ash conveying pipeline;

[0011] The rotating part includes a threaded sleeve, a rotating blade and a cleaning ring;

[0012] The threaded sleeve is threadedly sleeved on the outer side of the threaded screw rod, and a plurality of rotary blades are provided, and the plurality of rotary blades are arranged around the outer side of the circumference of the threaded sleeve and are fixed on the outer wall of the threaded sleeve at equal intervals;

[0013] The cleaning ring is coaxially arranged with the threaded screw rod, the inner wall of the cleaning ring is fixed with the rotary blade, and the outer wall of the cleaning ring is slidingly fitted with the inner wall of the ash conveying pipeline.

[0014] As a further supplement to this solution, chamfers are provided on the inner edges of both ends of the cleaning ring.

[0015] As a further supplement to the present solution, a plurality of scraping teeth are fixed at equal distances on both ends of the cleaning ring, and the scraping teeth are slidably fitted against the inner wall of the ash conveying pipe.

[0016] As a further supplement to the present solution, cleaning brush rings are coaxially fixed to both ends of the threaded sleeve, and the cleaning brush rings are in contact with the surface of the threaded screw.

[0017] As a further supplement to the present solution, the inner surfaces of the rotating part, the threaded screw and the ash conveying pipe are all coated with an antistatic coating.

[0018] As a further supplement to the present solution, a plurality of pilot-operated automatic bolt-forming valves are installed at equal intervals along the length direction of the ash conveying pipeline, and the ash conveying pipeline is connected to a common gas pipeline through the plurality of pilot-operated automatic bolt-forming valves.

[0019] In summary, the technical effects and advantages of the utility model are:

[0020] 1. In the utility model, through the coordinated arrangement of the threaded sleeve, the rotary vane, the cleaning ring and the threaded screw, the airflow carries the material toward the ash bin, drives the rotary vane to rotate, and the rotary vane drives the threaded sleeve to rotate. The threaded sleeve and the threaded screw cooperate with each other, so that the threaded sleeve rotates and moves back and forth along the length direction of the threaded screw, thereby driving the cleaning ring to move in line with the ash conveying pipe, and then cleaning the dust attached to the inner wall of the ash conveying pipe. Compared with the arrangement of multiple cleaning structures in the public documents, this scheme only needs to arrange one ash removal unit on the inner side of the ash conveying pipe, which greatly reduces the resistance to material transportation and has a better cleaning effect.

[0021] 2. In the utility model, a plurality of scraping teeth are fixed at equal distances on both ends of the cleaning ring. The scraping teeth rotate with the cleaning ring to scrape off the dust attached to the inner wall of the ash conveying pipe, and the cleaning effect is better. In addition, cleaning brush rings are coaxially fixed on both ends of the threaded sleeve. The cleaning brush ring can brush off the materials attached to the surface of the threaded screw during the rotation of the threaded sleeve, thereby ensuring the stable cooperation between the threaded screw and the threaded sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 It is a schematic diagram of a partial cutaway structure in this embodiment;

[0024] Figure 2 It is a schematic diagram of a partial cross-sectional structure in this embodiment;

[0025] Figure 3 is a schematic diagram of the three-dimensional structure of the rotating part in this embodiment;

[0026] Figure 4 Schematic diagram of the structure of the dust cleaning ring in this embodiment;

[0027] Figure 5 It is a schematic diagram of the planar structure of the pneumatic conveying device of a thermal power plant in this embodiment.

[0028] In the figure: 1. dust collector hopper; 2. silo pump; 3. ash conveying pipeline; 4. accompanying air pipeline; 5. pilot-operated automatic plug valve; 6. pressure reducing valve; 7. ash removal unit; 71. rotating part; 711. threaded sleeve; 712. rotary vane; 713. ash cleaning ring; 7131. chamfer; 7132. ash scraping teeth; 714. ash cleaning brush ring; 72. threaded screw. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] Example: Reference Figure 1-5 The ash removal structure of a pneumatic conveying device of a thermal power plant shown in the figure includes an ash removal unit 7 arranged on the inner side of the ash conveying pipeline 3, and the ash removal unit 7 is located on the inner side of the straight pipe section of the ash conveying pipeline 3, the ash removal unit 7 includes a rotating part 71 and a threaded screw 72, the threaded screw 72 is fixedly installed on the inner side of the ash conveying pipeline 3, and is arranged coaxially with the ash conveying pipeline 3, the rotating part 71 includes a threaded sleeve 711, a rotary vane 712 and a cleaning ring 713, the threaded sleeve 711 is threadedly sleeved on the outer side of the threaded screw 72, a plurality of rotary vanes 712 are arranged, and the plurality of rotary vanes 712 are arranged around the outer side of the circumference of the threaded sleeve 711 and are equidistantly fixed on the outer wall of the threaded sleeve 711, the cleaning ring 713 is arranged coaxially with the threaded screw 72, and the inner wall of the cleaning ring 713 is fixed to the rotary vane 712, and the outer wall of the cleaning ring 713 slides in contact with the inner wall of the ash conveying pipeline 3.

[0031] Through the coordinated arrangement of the threaded sleeve 711, the rotary vane 712, the cleaning ring 713 and the threaded screw 72, the airflow carries the material toward the ash bin, driving the rotary vane 712 to rotate, and the rotary vane 712 drives the threaded sleeve 711 to rotate. The threaded sleeve 711 and the threaded screw 72 cooperate with each other, so that the threaded sleeve 711 rotates while moving back and forth along the length direction of the threaded screw 72, thereby driving the cleaning ring 713 to move in close contact with the ash conveying pipe 3, thereby cleaning the dust attached to the inner wall of the ash conveying pipe 3. Compared with the arrangement of multiple cleaning structures in the public documents, this scheme only needs to set one ash removal unit 7 on the inner side of the ash conveying pipe 3, which greatly reduces the resistance to material transportation and has a better cleaning effect.

[0032] Among them, the inner edges of both ends of the cleaning ring 713 are provided with chamfers 7131 to reduce the resistance to the material.

[0033] Among them, multiple scraping teeth 7132 are equidistantly fixed on both ends of the cleaning ring 713, and the scraping teeth 7132 are slidingly fitted with the inner wall of the ash conveying pipe 3. The scraping teeth 7132 rotate with the cleaning ring 713 to scrape off the dust attached to the inner wall of the ash conveying pipe 3, and the cleaning effect is better.

[0034] In order to remove the materials attached to the surface of the threaded screw 72, cleaning brush rings 714 are coaxially fixed to the two ends of the threaded sleeve 711. The cleaning brush rings 714 are in contact with the surface of the threaded screw 72. As the threaded sleeve 711 rotates, the cleaning brush rings 714 can brush off the materials attached to the surface of the threaded screw 72, thereby ensuring the stable cooperation between the threaded screw 72 and the threaded sleeve 711.

[0035] Among them, the inner surfaces of the rotating part 71, the threaded screw 72 and the ash conveying pipe 3 are all coated with an anti-static coating, which can achieve an anti-static effect.

[0036] In addition, the ash conveying pipeline 3 is equidistantly installed with multiple pilot-operated automatic bolt-forming valves 5 along its length direction, and the ash conveying pipeline 3 is connected to a common air pipeline 4 through multiple pilot-operated automatic bolt-forming valves 5. The air pipeline 4 provides an air source for the pneumatic conveyor to maintain a normal ash conveying pressure, so that the material is always in a suspended state and the amount of material deposition is reduced.

[0037] The pneumatic conveying device of the thermal power plant includes a dust collector ash hopper 1, a silo pump 2 and an ash conveying pipeline 3. Compressed air is used to convey the ash in the dust collector ash hopper 1 to the ash storage through the silo pump 2 and the ash conveying pipeline 3 in sequence. Among them, the silo pump 2 only retains the main air intake, and the main air intake inlet of the silo pump 2 is installed with a pressure reducing valve 6.

[0038] The working principle of the utility model is as follows: in the process of airflow carrying materials toward the ash bin, the rotary blade 712 is driven to rotate, and the rotary blade 712 drives the threaded sleeve 711 to rotate, and the threaded sleeve 711 and the threaded screw 72 cooperate with each other, so that the threaded sleeve 711 rotates and reciprocates along the length direction of the threaded screw 72, thereby driving the cleaning ring 713 to move in close contact with the ash conveying pipe 3, and then removing the dust attached to the inner wall of the ash conveying pipe 3; in addition, the scraping teeth 7132 rotate with the cleaning ring 713 to scrape off the dust attached to the inner wall of the ash conveying pipe 3, and the cleaning effect is better, and the cleaning brush ring 714 can brush off the materials attached to the surface of the threaded screw 72 as the threaded sleeve 711 rotates, thereby ensuring the stable cooperation between the threaded screw 72 and the threaded sleeve 711.

[0039] Finally, it should be noted that the above is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. An ash removal structure of a pneumatic conveying device in a thermal power plant, characterized in that: It comprises an ash removal unit (7) arranged on the inner side of the ash conveying pipeline (3), and the ash removal unit (7) is located on the inner side of the straight pipe section of the ash conveying pipeline (3); The ash removal unit (7) comprises a rotating part (71) and a threaded screw (72); The threaded screw (72) is fixedly installed on the inner side of the ash conveying pipeline (3) and is coaxially arranged with the ash conveying pipeline (3); The rotating part (71) comprises a threaded sleeve (711), a rotating blade (712) and a cleaning ring (713); The threaded sleeve (711) is threadably sleeved on the outer side of the threaded screw rod (72); a plurality of rotary blades (712) are provided, and the plurality of rotary blades (712) are arranged around the outer side of the circumference of the threaded sleeve (711) and are fixed on the outer wall of the threaded sleeve (711) at equal intervals; The cleaning ring (713) is coaxially arranged with the threaded screw (72), and the inner wall of the cleaning ring (713) is fixed to the rotary blade (712), and the outer wall of the cleaning ring (713) is slidably fitted to the inner wall of the ash conveying pipe (3).

2. The ash removal structure of the pneumatic conveying device of a thermal power plant according to claim 1, characterized in that: The inner edges of both ends of the cleaning ring (713) are provided with chamfers (7131).

3. The ash removal structure of the pneumatic conveying device of a thermal power plant according to claim 1, characterized in that: A plurality of scraping teeth (7132) are fixed at equal intervals on both ends of the ash cleaning ring (713), and the scraping teeth (7132) are slidably fitted with the inner wall of the ash conveying pipe (3).

4. The ash removal structure of the pneumatic conveying device of a thermal power plant according to claim 1, characterized in that: Both ends of the threaded sleeve (711) are coaxially fixed with cleaning brush rings (714), and the cleaning brush rings (714) are in contact with the surface of the threaded screw (72).

5. The ash removal structure of the pneumatic conveying device of a thermal power plant according to claim 1, characterized in that: The inner surfaces of the rotating part (71), the threaded screw (72) and the ash conveying pipeline (3) are all coated with an antistatic coating.

6. The ash removal structure of the pneumatic conveying device of a thermal power plant according to claim 1, characterized in that: The ash conveying pipeline (3) is provided with a plurality of pilot-operated automatic bolt-forming valves (5) equidistantly installed along its length direction, and the ash conveying pipeline (3) is connected to a common gas pipeline (4) via the plurality of pilot-operated automatic bolt-forming valves (5).

Images