Blast furnace gas dry dedusting cloth bag blowback system

Abstract

The utility model discloses a blast furnace gas dry dedusting cloth bag blowback system which comprises a dedusting box, a frame and a cloth bag, the frame and the cloth bag are arranged in the dedusting box, a pressure pump is arranged on a gas outlet pipe of the dedusting box, a pressure relief pipe is arranged at the top of the dedusting box, and the gas outlet pipe and the pressure relief pipe are both communicated with a clean gas pipe network. A vertical pipe is arranged in each frame, the lower end of each vertical pipe is blocked by a blocking plate, a sliding plate capable of sliding up and down is arranged in each vertical pipe, a spring is arranged between each sliding plate and the corresponding blocking plate, a vertical rod is arranged on the lower surface of each sliding plate, and the lower end of each vertical rod penetrates through the corresponding blocking plate and then is connected with an impact block; the air distribution pipe is communicated with each vertical pipe through a branch pipe, an air inlet pipe and an air outlet pipe are arranged on the air distribution pipe, a fan and an air inlet valve are sequentially arranged on the air inlet pipe in the airflow direction, and a pressure release valve is arranged on the air outlet pipe. In conclusion, the dust removal device has the advantages of being low in use cost, high in working efficiency and good in dust removal effect.

Description

Technical Field

[0001] The utility model relates to the technical field of bag reverse blowing and dust cleaning, in particular to a bag reverse blowing system for dry dedusting of blast furnace gas. Background Art

[0002] As a mature dust removal process, dry dedusting of blast furnace gas has been used in most blast furnaces in China at present. It is mainly used to purify the crude gas generated in the production processes such as blast furnace ironmaking, so as to reduce the content of pollutants in the discharged gas. The dust removal bag is a key part during the operation of the bag filter, which can be regarded as the heart of the bag filter. It is usually cylindrical, vertically suspended in the dust collector, and its interior is supported by brackets. During the use of the dust collector, dust will continuously adhere to the dust removal bag. In order to ensure the dust removal efficiency and effect, it is necessary to deal with the dust on the dust removal bag.

[0003] At present, the dust cleaning treatment of the dust removal bag mostly adopts a nitrogen reverse blowing system. In this system, nitrogen pipelines are installed side by side in the dust removal box body. One end of the nitrogen pipeline is connected to the nitrogen reverse blowing tank through a stop valve and a metal flexible joint, and the other end is connected to the blowing pipe of the dust removal bag in the dust removal box body. Submerged pulse solenoid valves are installed on the nitrogen pipelines. This method has the advantages of simple process pipeline, small investment, and stable nitrogen gas source. However, in the long-term use process, the following problems are found: First, it needs to consume a large amount of nitrogen, and the usage cost is relatively high. At the same time, a large amount of nitrogen introduced into the pipe network will increase the nitrogen content in the blast furnace gas pipe network, affecting the subsequent use of the gas; Second, as the use time prolongs, the valves and nitrogen pipelines are prone to damage. On the one hand, it will cause the problem of nitrogen leakage, resulting in a large waste of nitrogen. On the other hand, the repair and replacement of the valves and nitrogen pipelines are relatively troublesome, which will not only cause waste of manpower and material resources, but also increase the dust cleaning cost of the dust removal bag and reduce the dust cleaning efficiency of the dust removal bag; In addition, after the dust cleaning treatment, some relatively stubborn dust still adheres to the bag, resulting in a poor dust cleaning effect. Therefore, it is objectively necessary to develop a bag reverse blowing system for dry dedusting of blast furnace gas with low use cost, high working efficiency, and good dust cleaning effect. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a bag reverse blowing system for dry dedusting of blast furnace gas with low use cost, high working efficiency, and good dust cleaning effect.

[0005] The purpose of the present utility model is achieved as follows. It includes a dust removal box, a frame and cloth bags arranged inside the dust removal box. A pressure pump is provided on the gas outlet pipe of the dust removal box. The inlet and outlet ends of the pressure pump are connected in parallel with a bypass pipe. A pressure relief pipe is provided at the top of the dust removal box. Valves are provided on the gas inlet pipe, gas outlet pipe, pressure relief pipe and bypass pipe of the dust removal box. The gas outlet pipe and the pressure relief pipe are both connected to the clean gas pipe network. A vertical pipe is arranged inside each frame. The upper end of the vertical pipe is connected to the top of the dust removal box, and the lower end is blocked by a plug plate. A sliding plate that can slide up and down is arranged inside the vertical pipe. A spring is arranged between the sliding plate and the plug plate. A vertical rod is arranged on the lower surface of the sliding plate. The lower end of the vertical rod passes through the plug plate and is connected with an impact block. An air vent gap is left between the vertical rod and the plug plate. A gas distribution pipe is arranged above the dust removal box. The gas distribution pipe is connected to each vertical pipe through a branch pipe. An air inlet pipe and an air outlet pipe are provided on the gas distribution pipe. A fan and an inlet valve are arranged in sequence along the gas flow direction on the air inlet pipe. A pressure relief valve is provided on the air outlet pipe.

[0006] Further, a plurality of vertical bars are evenly distributed in a circumferential direction on the inner wall of the vertical pipe, and grooves matching the vertical bars are processed on the edge of the sliding plate.

[0007] Further, a limiting block is arranged on the vertical pipe below the sliding plate.

[0008] Further, a soft pad is arranged on the lower surface of the impact block.

[0009] Further, the upper end of the vertical pipe and the top of the dust removal box are connected by a flange and bolts.

[0010] Further, an arc-shaped elastic strip is arranged on the impact block, and the arc-shaped elastic strip is closely attached to the side wall of the frame.

[0011] The utility model is used for the reverse blowing and dust cleaning of the filter bags of the bag filter in the dry dedusting system of blast furnace gas. During the dust cleaning process, first, the valves on the gas inlet pipe and the gas outlet pipe are shut down to stop the dust cleaning and dust removal work of the bag filter. Then, the valve on the pressure relief pipe is opened, and the clean gas in the dust removal box enters the clean gas pipe network through the pressure relief pipe. When the air pressure in the dust removal box drops to a certain level, the valve on the pressure relief pipe is shut down, the valve on the gas outlet pipe is opened, and at the same time, the valve on the bypass pipe is closed. The pressure pump is started to extract the clean gas from the clean gas pipe network. The clean gas flows reversely into the dust removal box through the gas outlet pipe to conduct reverse blowing and dust cleaning on the filter bags. At the same time, the fan is started, and the air enters the vertical pipe after passing through the air inlet pipe, the air distribution pipe, and the branch pipe in sequence, increasing the internal pressure of the vertical pipe above the slide plate. As the pressure continuously increases, the slide plate is pushed to move downward. When the slide plate moves downward, it overcomes the internal pressure of the frame and the elastic force of the spring, and the spring contracts, driving the vertical rod and the impact block to move downward until the impact block collides with the bottom of the frame, causing the vibration of the frame and the filter bags, promoting the shedding of the dust on the surface of the filter bags. Subsequently, the valve on the pressure relief pipe is opened for pressure relief, and the filter bags return from the expanded state to the contracted and deflated state. At the same time, the fan and the intake valve are shut down, the pressure relief valve is opened, and the air is discharged from the air outlet pipe. The pressure in the vertical pipe becomes smaller, and the slide plate moves upward under the action of the spring, driving the impact block to move upward and reset at the same time. The pressure relief valve is closed, and then the pressure pump is started... and so on. The above steps are repeated multiple times, making the filter bags continuously expand and deflate, and at the same time, the impact block continuously impacts the frame to generate vibration, thereby realizing the cleaning of the dust on the filter bags. In the utility model, the gases used in the entire dust cleaning process are air and the clean gas in the clean gas pipe network, and the air does not enter the clean gas pipe network, so there will be no waste of nitrogen in the traditional nitrogen reverse blowing system. At the same time, no new gas will pour into the clean gas pipe network, and it will not affect the component content and quality of the clean gas. Secondly, compared with the traditional nitrogen reverse blowing system, there will be no damage to the relevant gate valves and nitrogen pipelines, which not only eliminates the problem of nitrogen leakage but also avoids the maintenance and replacement of nitrogen pipelines, reduces the dust cleaning cost of the filter bags, improves the dust cleaning efficiency of the filter bags, extends the continuous working time of the filter bags, can purify and remove dust from more raw gas, and improves the dust removal efficiency of the raw gas. In addition, compared with the existing situation where the filter bags only rely on expansion and contraction during dust cleaning, the utility model simultaneously adopts the method of vibrating the frame to cause mechanical vibration of the filter bags, promoting the rupture and shedding of the dust layer accumulated on the filter bags, ensuring that stubborn dust can also be cleaned, and improving the dust cleaning effect of the filter bags. To sum up, the utility model has the advantages of low use cost, high working efficiency, and good dust cleaning effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is the overall structural schematic diagram of the utility model;

[0013] Figure 2 is Figure 1 the structural schematic diagram of node A in

[0014] Figure 3 This is a top view structural schematic diagram of the slide plate 10 and the vertical pipe 9 in the present utility model;

[0015] In the figure: 1 - dust removal box, 2 - frame, 3 - cloth bag, 4 - gas outlet pipe, 5 - pressure pump, 6 - pressure relief pipe, 7 - valve, 8 - clean gas pipe network, 9 - vertical pipe, 10 - slide plate, 11 - spring, 12 - vertical rod, 13 - impact block, 14 - gas distribution pipe, 15 - branch pipe, 16 - fan, 17 - intake valve, 18 - pressure relief valve, 19 - vertical strip, 20 - limit block, 21 - soft pad, 22 - flange, 23 - arc-shaped elastic strip. Specific embodiments

[0016] The present utility model will be further described below in conjunction with the accompanying drawings, but it is not limited to the present utility model in any way. Any changes or improvements made based on the present utility model fall within the protection scope of the present utility model.

[0017] As Figures 1 to 3 shown, the present utility model includes a dust removal box 1, a frame 2 and a cloth bag 3 arranged in the dust removal box 1. The dust removal box 1, the frame 2 and the cloth bag 3 are all existing cloth bag dust collector structures. Among them, the cloth bag 3 is sleeved on the frame 2, and the frame 2 supports the cloth bag 3. A pressure pump 5 is arranged on the gas outlet pipe 4 of the dust removal box 1. The inlet and outlet ends of the pressure pump 5 are connected in parallel with a bypass pipe. When the cloth bag dust collector operates normally, the raw coal gas enters the dust removal box 1 from the gas inlet pipe, and after being filtered and dust-removed by the cloth bag 3, the clean coal gas is discharged from the gas outlet pipe 4. A pressure relief pipe 6 is arranged at the top of the dust removal box 1. Valves 7 are arranged on the gas inlet pipe, the gas outlet pipe 4, the pressure relief pipe 6 and the bypass pipe of the dust removal box 1. The gas outlet pipe 4 and the pressure relief pipe 6 are both connected to the clean gas pipe network 8. A vertical pipe 9 is arranged inside each frame 2. The upper end of the vertical pipe 9 is connected to the top of the dust removal box 1, and the lower end is blocked by a plug plate. A slidable slide plate 10 is arranged in the vertical pipe 9. A spring 11 is arranged between the slide plate 10 and the plug plate. A vertical rod 12 is arranged on the lower surface of the slide plate 10. The lower end of the vertical rod 12 passes through the plug plate and is connected with an impact block 13. An air vent gap is left between the vertical rod 12 and the plug plate. The gas in the vertical pipe 9 below the slide plate 10 enters and exits through the air vent gap. In actual use, in order to ensure the smooth flow of gas, air vent holes can be processed on the side wall of the lower part of the vertical pipe 9. A gas distribution pipe 14 is arranged above the dust removal box 1. The gas distribution pipe 14 is connected to each vertical pipe 9 through a branch pipe 15. An air inlet pipe and an air outlet pipe are arranged on the gas distribution pipe 14. A fan 16 and an intake valve 17 are arranged in sequence along the gas flow direction on the air inlet pipe. A pressure relief valve 18 is arranged on the air outlet pipe.

[0018] After the ash is removed from the bag 10, the gas filter 10 will be turned off, and the dust removal work of the bag 10 will be stopped. Then, the valve 7 on the pressure relief pipe 6 will be opened, and the clean coal gas in the dust box 1 will enter the clean coal gas pipeline network 8 through the pressure relief pipe 6. When the air pressure in the dust box 1 drops to a certain level, the valve 7 on the pressure relief pipe 6 will be closed, the valve 7 on the gas outlet pipe 4 will be opened, and the valve 7 on the bypass pipe will be closed at the same time, and the pressure pump 5 will be started to extract the clean coal gas in the clean coal gas pipeline network 8. The clean gas will flow into the dust box 1 in the reverse direction through the gas outlet pipe 4, and the bag 3 will be back-blown for cleaning. At the same time, the fan 16 will be started, and the air will enter the vertical pipe 9 after passing through the air intake pipe, the air distribution pipe 14 and the branch pipe 15 in turn, thereby increasing the internal pressure of the vertical pipe 9 above the slide plate 10. As the pressure continues to increase, the slide plate 10 will be pushed to The plate 10 moves downward, and when the slide plate 10 moves downward, it overcomes the internal pressure of the frame 2 and the elastic force of the spring 11. The spring 11 contracts, driving the vertical rod 12 and the impact block 13 to move downward until the impact block 13 collides with the bottom of the frame 2, causing the frame 2 and the cloth bag 3 to vibrate, promoting the shedding of dust on the surface of the cloth bag 3, and then opening the valve 7 on the pressure relief pipe 6 to release the pressure, and the cloth bag 3 recovers from the expanded state to the deflated state. At the same time, the fan 16 and the air inlet valve 17 are turned off, and the pressure relief valve 18 is opened, and the air is discharged from the air outlet pipe. The pressure in the vertical pipe 9 becomes smaller, and the slide plate 10 moves upward under the action of the spring 11, and at the same time drives the impact block 13 to move up and reset, closes the pressure relief valve 18, and then starts the pressure pump 5... and so on, repeat the above steps many times, so that the cloth bag 3 continues to expand and deflate, and the impact block 13 continues to hit the frame 2 to generate vibration, thereby realizing the cleaning of the dust on the cloth bag 3.

[0019] In the present invention, the gases used in the whole cleaning process are air and clean coal gas in the clean coal gas network 8, and the air does not enter the clean coal gas network 8, so there will be no waste of nitrogen in the traditional nitrogen backflush system. At the same time, no new gas will flow into the clean coal gas network 8, and the component content and quality of the clean coal gas will not be affected. Secondly, compared with the traditional nitrogen backflush system, there will be no damage to the relevant gate valves and nitrogen pipelines, which not only eliminates the leakage problem of nitrogen, but also avoids the maintenance and replacement of the nitrogen pipeline, reduces the cleaning cost of the bag 3, improves the cleaning efficiency of the bag 3, and extends the continuous working time of the bag 3. More raw coal gas can be purified and dusted, and the dust removal efficiency of the raw coal gas is improved. In addition, compared with the existing bag 3 that only relies on the expansion and contraction of the bag 3 when cleaning, the present invention also adopts a vibration frame 2 to cause the bag 3 to vibrate mechanically, promote the dust layer attached to the bag 3 to break and fall off, ensure that stubborn dust can also be cleaned, and improve the cleaning effect of the bag 3.

[0020] A plurality of vertical bars 19 are evenly distributed in a circumferential manner on the inner wall of the vertical pipe 9. The edge of the sliding plate 10 is processed with grooves matching the vertical bars 19. The sliding plate 10 slides up and down along the vertical pipe 9. In the actual use process, it is found that the sliding plate 10 will be skewed, resulting in the sliding plate 10 not being able to move smoothly in the vertical pipe 9, or even getting stuck, affecting the normal operation of the dust removal of the cloth bag 3. To solve this problem, the structure of the vertical bars 19 and the grooves is provided to guide the process of the sliding plate 10 moving up and down and position the sliding plate 10, which can not only prevent the sliding plate 10 from being skewed and twisted, but also enable the sliding plate 10 to move up and down smoothly.

[0021] A limit block 20 is provided on the vertical pipe 9 below the sliding plate 10. When the sliding plate 10 slides down to compress the spring 11, the spring 11 will be compressed to the limit state. Over time, the service life of the spring 11 will be shortened, or even the spring 11 will be damaged and fail. To extend the service life of the spring 11, the limit block 20 is provided. When the sliding plate 10 moves down to the position of the limit block 20, it is blocked by the limit block 20 and cannot continue to compress the spring 11, thereby playing a role in protecting the spring 11.

[0022] A soft pad 21 is provided on the lower surface of the impact block 13. The impact block 13 and the bottom of the frame 2 will collide continuously. As the use time extends, it may cause damage to the bottom of the frame 2. To avoid this situation, the soft pad 21 is provided to generate a certain buffer during the collision, slow down the damage speed of the bottom of the frame 2, and extend the service life of the frame 2.

[0023] To facilitate the disassembly and installation of the vertical pipe 9 and its various internal components, the upper end of the vertical pipe 9 is connected to the top of the dust removal box 1 through a flange 22 and bolts. When it is necessary to repair or replace components such as the sliding plate 10 and the spring 11, the vertical pipe 9 can be removed by the flange 22 and bolts.

[0024] An arc-shaped elastic strip 23 is provided on the impact block 13. The arc-shaped elastic strip 23 is closely attached to the side wall of the frame 2. The arc-shaped elastic strip 23 is an existing structure and is made of an elastic material. It is closely attached to the frame 2 under the action of elastic force. When the impact block 13 moves up and down, it will drive the arc-shaped elastic strip 23 to move up and down together. While the arc-shaped elastic strip 23 is closely attached to the frame 2, it slides and rubs on the frame 2. And since the surface of the frame 2 is usually not a smooth plane, during the process of sliding and rubbing of the arc-shaped elastic strip 23, it will cause the vibration of the frame 2 and the cloth bag 3, thereby promoting the rupture and shedding of dust from the cloth bag 3 and improving the dust cleaning efficiency and effect.

Claims

1. A dry dedusting bag reverse blowing system for blast furnace gas, comprising a dust removal box (1), a frame (2) and bags (3) arranged in the dust removal box (1), characterized in that : A pressure pump (5) is provided on the gas outlet pipe (4) of the dust removal box (1). The inlet and outlet ends of the pressure pump (5) are connected in parallel with a bypass pipe. A pressure relief pipe (6) is provided at the top of the dust removal box (1). Valves (7) are provided on the gas inlet pipe, gas outlet pipe (4), pressure relief pipe (6) and bypass pipe of the dust removal box (1). The gas outlet pipe (4) and the pressure relief pipe (6) are both connected to the clean gas pipe network (8). A vertical pipe (9) is provided inside each frame (2). The upper end of the vertical pipe (9) is connected to the top of the dust removal box (1), and the lower end is sealed by a plug plate. A sliding plate (10) that can slide up and down is provided inside the vertical pipe (9). A spring (11) is provided between the sliding plate (10) and the plug plate. A vertical rod (12) is provided on the lower surface of the sliding plate (10). The lower end of the vertical rod (12) passes through the plug plate and is connected to an impact block (13). An air vent gap is left between the vertical rod (12) and the plug plate. A gas distribution pipe (14) is provided above the dust removal box (1). The gas distribution pipe (14) is connected to each vertical pipe (9) through a branch pipe (15). An air inlet pipe and an air outlet pipe are provided on the gas distribution pipe (14). A fan (16) and an inlet valve (17) are sequentially provided on the air inlet pipe along the air flow direction. A pressure relief valve (18) is provided on the air outlet pipe.

2. The bag reverse blowing system for dry dedusting of blast furnace gas according to claim 1, wherein : A plurality of vertical strips (19) are evenly distributed in a circle on the inner wall of the vertical pipe (9). The edge of the sliding plate (10) is processed with a groove matching the vertical strips (19).

3. The dry dedusting cloth bag backwashing system for blast furnace gas according to claim 1, characterized in that : A limiting block (20) is provided on the vertical pipe (9) below the sliding plate (10).

4. The dry dedusting cloth bag back-blowing system for blast furnace gas according to claim 1, characterized in that : A soft pad (21) is provided on the lower surface of the impact block (13).

5. The dry dedusting cloth bag back-blowing system for blast furnace gas according to claim 1, wherein : The upper end of the vertical pipe (9) and the top of the dust removal box (1) are connected by a flange (22) and bolts.

6. The dry dedusting bag reverse blowing system for blast furnace gas according to claim 1, characterized in that : An arc-shaped elastic strip (23) is provided on the impact block (13), and the arc-shaped elastic strip (23) is closely attached to the side wall of the frame (2).

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