Anti-blocking structure of boiler dedusting pneumatic ash conveying system

Abstract

The utility model discloses an anti-blocking structure of a boiler dedusting pneumatic ash conveying system, and belongs to the field of boiler dedusting. According to the utility model, the pneumatic ash conveying system in the prior art is mainly improved, and the plurality of blowing accompanying branch pipes which are vertically connected are changed to be connected with the main ash conveying pipeline at a certain angle, so that the erosive wear to the inner wall of the main ash conveying pipeline during fluidization stirring of compressed air and pulverized coal ash is reduced. Meanwhile, all the integrally-formed pipelines are arranged to be of a sectional type structure suitable for overhauling, the pipelines are connected through flanges, disassembly and assembly are convenient, the sealing performance of the pipelines can be guaranteed, and dredging and overhauling are facilitated. And a throttling hole and a check valve are further arranged in the blowing-accompanying branch pipe, so that the phenomenon that residual pulverized coal ash in the ash conveying pipeline flows back into the blowing-accompanying pipeline to cause blockage is prevented.

Description

Technical Field

[0001] The utility model belongs to the field of boiler dust removal, and in particular relates to an anti-blocking structure of a boiler dust removal pneumatic ash conveying system. Background Art

[0002] The production process of coal-fired boilers is a process of continuous heat exchange between circulating water and the fuel burning in the furnace. Boilers in the power industry generally use combustible materials such as coal powder, coal gas or natural gas as fuel. Mixed-fired boilers use gas fuel with a certain proportion of coal powder added as fuel.

[0003] Under the automatic combustion regulation of the boiler, the gas fuel can generally be completely burned in the boiler furnace and then discharged from the flue by the boiler ventilation equipment. The ash in the pulverized coal fuel is a non-combustible substance. Under the high temperature conditions of the furnace, the ash particles adhere to each other to form ash slag, and form fly ash in the flue gas at the tail of the boiler with the solid combustibles that have not been completely burned. If the fly ash particles are entrained in the circulating air and discharged into the atmosphere through the chimney, it will inevitably cause great pollution to the environment where humans live. Industrial boilers generally use electrostatic precipitators to separate the dust from the furnace flue gas after combustion, so the dust removal system is one of the essential links for the normal operation of the boiler.

[0004] The coal ash produced after the combustion of coal-fired boilers is collected by dust collectors, and then transported to the ash storage bin through pipelines using compressed air for collection and storage, and then transported to other users by suction and discharge tank trucks. Usually, each boiler is equipped with a set of pneumatic ash conveying system, which consists of a main soot blowing pipe, a companion blowing mother pipe and an auxiliary blowing pipe. The companion blowing mother pipe is vertically connected to the main soot blowing pipe through multiple companion blowing branches, and the auxiliary blowing pipe is connected to the output end of the main soot blowing pipe and finally connected to the ash storage bin.

[0005] Before starting the ash conveying system, the coal powder ash collected by the dust collector is first used, and the feed valve above the silo pump is opened and closed according to the set time cycle to load the ash into the silo pump. The silo pump is connected to three pipes, and compressed air is introduced into the three pipes.

[0006] After opening the discharge valve of the main ash conveying pipeline, first start the start ball valve of the accompanying blowing mother pipe, and let the compressed air flow into the accompanying blowing mother pipe, and then transport the compressed air through the accompanying blowing branch pipe. The compressed air fluidizes the pulverized coal ash in the ash conveying pipeline to prevent the pulverized coal ash from accumulating and clogging in the main ash conveying pipeline. Then open the ball valve of the main ash blowing pipeline, and transport the compressed air to the main ash blowing pipeline to transport the pulverized coal ash. Finally, start the ball valve of the auxiliary blowing pipeline to strengthen the ash conveying power after the pulverized coal ash comes out of the main ash blowing pipeline, and assist in transporting the pulverized coal ash to the storage ash bin.

[0007] At present, this blowing method has the following problems:

[0008] 1. The accompanying blowing branch pipe is connected to the main ash conveying pipeline in a vertical direction. When compressed air is used to stir the coal fly ash, the inside of the main ash conveying pipeline will be directly scour and wear, which may easily cause the opposite side of the main ash conveying pipeline connected to the accompanying blowing branch pipe to be worn through, resulting in coal fly ash leakage.

[0009] 2. Due to the presence of certain humidity in compressed air, even when there is a accompanying blowing pipe to fluidize the coal fly ash, it is still possible that the coal fly ash will adhere to the pipe wall after long-term use, resulting in the internal space of the main ash conveying pipe becoming smaller. The main ash conveying pipe is very inconvenient to clean, and it is necessary to cut the main ash conveying pipe and then weld it after cleaning.

[0010] 3. After the ash conveying system completes the ash conveying, the coal powder ash remaining in the main ash conveying pipeline is easy to reverse into the accompanying blowing branch pipe, causing blockage of the accompanying blowing branch pipe and affecting normal production.

[0011] Therefore, in view of the above problems, a new design is needed that can solve the shortcomings of the ash conveying system in the prior art. Utility Model Content

[0012] In view of the above problems existing in the prior art, the purpose of the utility model is to provide an anti-blocking structure for a boiler dust removal pneumatic ash conveying system.

[0013] In order to solve the above problems, the technical solution adopted by the utility model is as follows:

[0014] A blocking prevention structure for a boiler dust removal pneumatic ash conveying system comprises a main ash conveying pipeline, a companion blowing pipeline and an auxiliary blowing pipeline. The main ash conveying pipeline is a multi-section structure. The companion blowing pipeline comprises a companion blowing mother pipe and a companion blowing branch pipe. One end of the companion blowing branch pipe is connected to the companion blowing mother pipe and the other end is connected to the main ash conveying pipeline. The companion blowing branch pipe is connected to the main ash conveying pipeline at a certain angle. The auxiliary blowing pipeline is connected to the terminal output part of the main ash conveying pipeline.

[0015] The angle between the accompanying blowing branch pipe and the main ash conveying pipeline is an acute angle along the gas blowing direction.

[0016] A throttling hole is arranged in the accompanying blowing branch pipe.

[0017] A one-way check valve is arranged in the accompanying blowing branch pipe.

[0018] Each section of the main ash conveying pipeline is connected via flanges.

[0019] The accompanying blowing pipeline extends into the main ash conveying pipeline, and the accompanying blowing pipeline is bent at a certain angle at the pipeline end in the main ash conveying pipeline.

[0020] The accompanying blowing branch pipe is connected with the accompanying blowing main pipe and the main ash conveying pipeline through a flange.

[0021] Compared with the prior art, the beneficial effects of the utility model are:

[0022] The utility model is mainly aimed at improving the pneumatic ash conveying system in the prior art, and changes the multiple vertically connected accompanying blowing branch pipes to be connected to the main ash conveying pipeline at a certain angle, so as to reduce the scouring and wear of the inner wall of the main ash conveying pipeline during the fluidization and stirring of compressed air and coal ash. At the same time, the integrally formed pipelines are set as a segmented structure suitable for maintenance, which is convenient for disassembly and assembly through flange connection, and its sealing can also be guaranteed, which is convenient for dredging and maintenance. A throttling hole and a check valve are also arranged inside the accompanying blowing branch pipe to prevent the coal ash remaining in the ash conveying pipeline from flowing back into the accompanying blowing pipeline and causing blockage. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a structural schematic diagram of Example 1;

[0024] Figure 2 This is a schematic diagram of the structure of Example 2;

[0025] In the figure: 1. Main ash transport pipeline; 2. Blowing main pipe; 3. Blowing branch pipe; 4. Auxiliary blowing pipeline; 5. Flange; 6. Throttle hole; 7. Check valve; 8. Ash storage. DETAILED DESCRIPTION

[0026] The utility model is further described below in conjunction with specific embodiments.

[0027] Example 1

[0028] like Figure 1 As shown, the utility model is improved based on the pneumatic ash conveying system in the prior art, and mainly includes a main ash conveying pipeline 1 connected to a silo pump, a companion blowing pipeline and an auxiliary blowing pipeline 3.

[0029] The three pipelines are connected to the silo pumps respectively, wherein one end of the main ash conveying pipeline 1 connected to the silo pump is provided with an input valve, and the other end of the main ash conveying pipeline 1 is connected to the ash bin 8 and is provided with an output valve.

[0030] The accompanying blowing pipeline is arranged on the side of the main ash conveying pipeline 1, and is divided into the accompanying blowing mother pipe 2 and the accompanying blowing branch pipe 3. One end of the accompanying blowing mother pipe 2 is connected to the silo pump and is provided with an input valve, and the other end is completely closed. A plurality of accompanying blowing branch pipes 3 are arranged on the side of the accompanying blowing mother pipe 2, one end of the accompanying blowing branch pipe 3 is connected to the accompanying blowing mother pipe 2, and the other end is connected to the main ash conveying pipeline 1.

[0031] The auxiliary blowing pipe 4 is also arranged on the side of the main ash conveying pipe 1. One end of the auxiliary blowing pipe 4 is connected to the silo pump, and the other end is connected to the output end pipe of the main ash conveying pipe 1, and an output valve is arranged at the front end of the confluence with the output pipe of the main ash conveying pipe 1.

[0032] The main ash conveying pipeline 1 is a split structure, which is composed of multiple shorter pipelines connected by flanges 5 to form a whole pipeline. The length of each pipeline section is suitable for maintenance and dredging.

[0033] Both ends of the accompanying blowing branch pipe 3 are also connected to the main ash conveying pipeline 1 and the accompanying blowing mother pipe 2 through flanges 5, and a throttle hole 6 and a check valve 7 are arranged inside the accompanying blowing branch pipe 3, wherein the throttle hole 6 is arranged near the accompanying blowing mother pipe 2, and the check valve 7 is arranged near the main ash conveying pipeline 1.

[0034] The accompanying blowing branch pipe 3 is installed at a certain angle. In this embodiment, the accompanying blowing branch pipe 3 is connected to the main ash conveying pipeline 1 obliquely forward based on the direction of compressed air entering. As a whole, the accompanying blowing branch pipe 3 is connected to the main ash conveying pipeline 1 at an acute angle. Figure 1 shown.

[0035] In actual use, the output valve of the main ash conveying pipeline 1 is opened first, and then the input valve of the accompanying blowing mother pipe 2 is opened, and compressed air is introduced into the main ash conveying pipeline 1 through the accompanying blowing branch pipe 3 to preliminarily purge the coal fly ash remaining in the main ash conveying pipeline 1, and the coal fly ash is fluidized in the subsequent ash conveying process to prevent the coal fly ash from agglomerating and remaining in the main ash conveying pipeline 1. The accompanying blowing branch pipe 3 is connected to the main ash conveying pipeline 1 at an oblique angle, which can better reduce the scouring and wear of the inner wall of the main ash conveying pipeline 1 by the compressed air when stirring the coal fly ash. At the same time, a throttle hole 6 is also provided in the accompanying blowing branch pipe 3, which can limit the flow rate of compressed air entering the main ash conveying pipeline 1, also to prevent the compressed air flow rate from being too large to scour and wear the inner pipe wall of the main ash conveying pipeline 1.

[0036] Then, the input valve of the main ash conveying pipeline 1 and the output valve of the auxiliary blowing pipeline 4 are opened at the same time. The silo pump now uses compressed air to introduce pulverized coal ash into the main ash conveying pipeline 1. After fluidization through the accompanying blowing pipeline, the pulverized coal ash is transported from the output end of the main ash conveying pipeline 1 to the ash bin 8. Behind the output valve of the main ash conveying pipeline 1 is the location where it converges with the auxiliary blowing pipeline 4. At this time, compressed air is directly introduced into the auxiliary blowing pipeline 4 to enhance the power of pulverized coal ash transportation, and finally the pulverized coal ash is sent to the ash bin 8.

[0037] After the ash conveying is completed, the input valve of the main ash conveying pipeline 1 is closed first, and then the input valve of the accompanying blowing pipeline and the output valve of the auxiliary blowing pipeline 4 are closed, and finally the output valve of the main ash conveying pipeline 1 is closed. In the process of closing the ash conveying system, there is still residual coal pulverized ash in the main ash conveying pipeline 1, and this part of the coal pulverized ash may reversely enter the accompanying blowing branch pipe 3, causing it to be blocked. At this time, the check valve 7 set in the accompanying blowing branch pipe 3 will take effect. The one-way check valve 7 will prevent the residual coal pulverized ash from entering the accompanying blowing branch pipe 3, and the coal pulverized ash accumulated on the check valve 7 will be blown back into the main ash conveying pipeline 1 during the next ash conveying, and finally sent to the ash storage 8.

[0038] When the main ash conveying pipeline 1 needs to be disassembled for thorough cleaning, the main ash conveying pipeline 1 can be disassembled directly through the flange 5, and the connection with the accompanying blowing branch pipe 3 can also be easily released. After cleaning, it can also be installed through the flange 5 to perform normal ash conveying operations. Compared with the operation process in the prior art that requires professionals to cut and clean, and then weld into a whole, it greatly saves the time and workload of cleaning and maintenance.

[0039] Example 2

[0040] The overall structure of this embodiment is exactly the same as that of the embodiment 1, except that the accompanying blowing branch pipe 3 is still connected to the main ash conveying pipeline 1 by vertical connection, but is extended inside the main ash conveying pipeline 1, and the end of the accompanying blowing branch pipe 3 extending into the main ash conveying pipeline 1 is bent at a certain angle, which is also to achieve the effect of changing the direction of the compressed air entering the main ash conveying pipeline 1. The specific structure is as follows: Figure 2 shown.

[0041] The scheme of this embodiment requires relatively small changes to the accompanying blowing pipeline. Unlike Example 1, it is not necessary to change the size and position of the holes for installing the accompanying blowing branch pipe 3 on the accompanying blowing mother pipe 2 and the main ash conveying pipeline 1. The changes to the existing equipment are relatively small, and it is suitable for large-scale modification of equipment. It is slightly worse than Example 1 in terms of later maintainability, but can also achieve the desired effect.

Claims

1. An anti-blocking structure for a boiler dust removal pneumatic ash conveying system, characterized in that: It includes a main ash conveying pipeline, a companion blowing pipeline and an auxiliary blowing pipeline. The main ash conveying pipeline is a multi-section structure. The companion blowing pipeline includes a companion blowing mother pipe and a companion blowing branch pipe. One end of the companion blowing branch pipe is connected to the companion blowing mother pipe and the other end is connected to the main ash conveying pipeline. The companion blowing branch pipe is connected to the main ash conveying pipeline at a certain angle, and the auxiliary blowing pipeline is connected to the terminal output part of the main ash conveying pipeline.

2. The anti-blocking structure of the boiler dust removal pneumatic ash conveying system according to claim 1 is characterized in that: The angle between the accompanying blowing branch pipe and the main ash conveying pipeline is an acute angle along the gas blowing direction.

3. The anti-blocking structure of the boiler dust removal pneumatic ash conveying system according to claim 1 is characterized in that: A throttling hole is arranged in the accompanying blowing branch pipe.

4. The anti-blocking structure of the boiler dust removal pneumatic ash conveying system according to claim 1 is characterized in that: A one-way check valve is arranged in the accompanying blowing branch pipe.

5. The anti-blocking structure of the boiler dust removal pneumatic ash conveying system according to claim 1 is characterized in that: Each section of the main ash conveying pipeline is connected via flanges.

6. The anti-blocking structure of the boiler dust removal pneumatic ash conveying system according to claim 1 is characterized in that: The accompanying blowing pipeline extends into the main ash conveying pipeline, and the accompanying blowing pipeline is bent at a certain angle at the pipeline end in the main ash conveying pipeline.

7. The anti-blocking structure of the boiler dust removal pneumatic ash conveying system according to claim 2 or 6, characterized in that: The accompanying blowing branch pipe is connected with the accompanying blowing main pipe and the main ash conveying pipeline through a flange.

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