Gas dust removal device, wind-down dust removal system, process and gas full recovery process

Abstract

The present application relates to a coal gas dust removal device, a wind-down dust removal system, a process and a coal gas full recovery process, which includes a dust removal tank, a filter bag, an ejector and an ash unloading tank, the filter bag is arranged in the dust removal tank, the ejector is arranged along the axial direction of the dust removal tank, and the first end of the ejector is located outside the dust removal tank, the second end of the ejector passes through the bottom of the filter bag and is located in the dust removal tank, the first end of the ejector is provided with a coal gas inlet and an ejector gas source inlet, the coal gas inlet is connected to the coal gas pipeline, and the coal gas to be dusted can be injected into the dust removal tank through the coal gas pipeline and the coal gas inlet; the ejector gas source inlet is connected to the gas source pipe, and the gas source pipe is provided with a gas source pipe on-off valve; the side wall of the dust removal tank and the top of the filter bag are connected with an exhaust pipe, and the coal gas to be dusted is discharged through the exhaust pipe after the dust removal is removed by the filter bag, and the ash unloading tank is connected to the bottom of the dust removal tank to collect dust falling from the filter bag. The present application has the effect of minimizing the floor space occupied by the dust removal equipment, thereby reducing the consumption of land resources.

Description

Technical Field

[0001] The present application relates to the technical field of blast furnace ironmaking, and in particular to a coal gas dust removal device, a wind-down dust removal system, a process and a coal gas full recovery process. Background Art

[0002] During the blast furnace shutdown process, a by-product called blast furnace gas is produced. Blast furnace gas contains combustible gas components such as carbon monoxide that can be utilized. Therefore, recycling the gas produced during the blast furnace shutdown process not only protects the environment, but also achieves the purpose of saving resources.

[0003] The existing technology for dust removal of idle gas mainly involves sequentially installing dust collectors, ejectors, exhaust pipes and gas networks on the blast furnace gas pipeline, and utilizing these devices to filter, discharge and recycle the blast furnace gas. However, since relatively more equipment is required, the entire installation project is huge in size, and the equipment occupies a large area, consuming relatively more land resources, and the noise generated also causes greater environmental pollution.

[0004] The existing gas full recovery process mainly involves sequentially installing ejectors, dust collectors, exhaust pipes, gas pipe networks and other equipment on the gas recovery pipeline of the material tank. The equipment occupies a large area and produces high noise.

[0005] With regard to the above-mentioned related technologies, there are defects in that the dust removal equipment occupies a large area and consumes relatively more land resources. Summary of the invention

[0006] In order to minimize the floor space occupied by dust removal equipment, thereby reducing the consumption of land resources and reducing noise pollution to the environment, the present application provides a blast furnace dust removal system and process.

[0007] The present application provides a blast furnace dust removal system and process using the following technical solutions:

[0008] A coal gas dust removal device comprises: a dust removal tank, a filter bag, an ejector and an ash discharge tank, wherein the filter bag is arranged in the dust removal tank, the ejector is arranged along the axial direction of the dust removal tank, and the first end of the ejector is located outside the dust removal tank, the second end of the ejector passes through the bottom of the filter bag and is located in the dust removal tank, the first end of the ejector is provided with a coal gas inlet and an ejection gas source inlet, the coal gas inlet is connected to a coal gas pipeline, a coal gas on-off valve and a coal gas pipeline main valve are provided on the coal gas pipeline, the coal gas to be dusted can be injected into the dust removal tank through the coal gas pipeline, the coal gas inlet and the ejector; the ejection gas source inlet is connected to a gas source pipe, and a gas source pipe on-off valve is provided on the gas source pipe; an exhaust pipe is connected to the side wall of the dust removal tank and above the filter bag, the coal gas to be dusted is discharged through the exhaust pipe after being dusted by the filter bag, and the ash discharge tank is connected to the bottom of the dust removal tank to collect dust falling from the filter bag.

[0009] By adopting the above technical scheme, the ejector, ash unloading tank and filter bag are all installed on the dust removal tank. When the blast furnace is in normal production, the ejector is used as the gas inlet pipe; when the blast furnace is shut down, the ejector can introduce a high-pressure gas source into the dust removal tank, and recover the blast furnace shut-down gas into the gas dust removal device. After filtering and purification, the gas is transported to the low-pressure pipeline network, thereby realizing the purification and recovery of the blast furnace shut-down gas. The gas dust removal device provided in the present application can operate in normal production state and shut-down and reduced wind state; in addition, on the whole, the entire device replaces the original blast furnace shut-down gas treatment facilities, occupies a small area, reduces the waste of land resources, and reduces noise and environmental pollution.

[0010] Preferably, the extension direction of the gas source pipe is perpendicular to the axial extension direction of the ejector.

[0011] By adopting the above technical solution, when the on-off valve of the air source pipe is opened, the gas in the air source pipe is sprayed from the ejector air source inlet to the inner wall of the ejector, and then enters the dust removal tank along the axial extension direction of the ejector. Therefore, the air flow speed in the ejector is relatively slow, and the noise generated is relatively small, thereby improving the comfort of the working environment.

[0012] Preferably, the extension direction of the gas source pipe is in the same direction as the axial extension direction of the ejector.

[0013] By adopting the above technical solution, when the on-off valve of the gas source pipe is opened, the gas in the gas source pipe is directly ejected from the ejector gas source inlet along the axial extension direction of the ejector into the dust removal tank. Therefore, the air flow speed in the ejector is relatively fast, thereby improving the dust removal efficiency and dust removal effect of the gas dust removal device.

[0014] Preferably, the upper end of the dust removal tank is located at the neck of the ejector.

[0015] By adopting the above technical solution, when the ejector is in working state, since the diameter of the constricted portion of the ejector is relatively small, noise will be generated when high-velocity gas passes through the constricted portion, and the upper end of the dust removal tank is located at the constricted portion of the ejector, so the dust removal tank wraps the constricted portion of the ejector, thereby reducing the range of noise propagation and improving the comfort of the working environment.

[0016] Preferably, a bypass air inlet pipe is connected to the bottom side of the dust removal tank, an air inlet of the bypass air inlet pipe is connected to the gas pipeline, an air outlet of the bypass air inlet pipe is located below the filter bag, and an air inlet on-off valve is provided on the bypass air inlet pipe.

[0017] By adopting the above technical solution, when the pressure in the blast furnace is high, the air intake on-off valve on the bypass air intake pipe is opened to increase the amount of gas entering the dust removal tank and improve the ventilation efficiency; in addition, the ejector channel can be closed to reduce the amount of dust in the ejector pipeline, thereby avoiding the blockage of the gas source pipe as much as possible.

[0018] Preferably, a pulse back-blowing device is connected to the side wall of the dust removal tank, an air blowing pipe is connected between the pulse back-blowing device and the dust removal tank, and an inlet of the air blowing pipe is located above the filter bag.

[0019] By adopting the above technical solution, when too much dust is deposited on the filter bags, the dust removal effect of the gas dust removal device will be reduced. Therefore, the dust deposited on the filter bags can be blown into the ash discharge pipe through the pulse backblowing device to restore the dust removal effect of the filter bags.

[0020] Preferably, a plurality of brackets are filled between the ejector and the inner wall of the dust removal tank, the plurality of brackets are arranged crosswise with each other, and the filter bag is wrapped in the brackets; and

[0021] One end of the bracket faces the inlet of the air blowing pipe, and the bracket is provided with a wave-enhancing funnel at one end close to the air blowing pipe and at the middle part of the bracket.

[0022] By adopting the above technical solution, several brackets are arranged crosswise with each other, so that the noise at the constricted end of the ejector is not easy to pass through the area between the ejector and the dust removal tank, thereby further enhancing the noise reduction effect; when it is necessary to remove the dust deposited on the filter bag, the pulse back-blowing device is started, and the wave-enhancing funnel close to the air pipe increases the air wave blown out of the air pipe, thereby improving the dust removal effect of the pulse back-blowing device on the filter bag; in addition, as the air wave moves to the middle position of the bracket, the energy of the air wave decreases, and it is not easy to remove the dust on the end of the filter bag away from the air pipe. At this time, the wave-enhancing funnel in the middle part of the bracket once again increases the air wave to enhance the dust removal effect of the pulse back-blowing device on the part of the filter bag away from the air pipe.

[0023] A blast furnace gas dry dust removal system, comprising:

[0024] blast furnace;

[0025] A primary dust collector is connected to the output port of the blast furnace through a first pipeline;

[0026] A secondary dust collector connected to the output port of the primary dust collector through a second pipeline, wherein the secondary dust collector includes at least a bag dust collector and at least one gas dust removal device, and the gas dust removal device is the gas dust removal device as described above; and

[0027] The gas pipeline network receives the gas discharged from the gas dust removal device and the bag dust collector.

[0028] By adopting the above technical scheme, the arrangement of the primary dust collector and the secondary dust collector greatly improves the dust removal effect of the system; in addition, the secondary dust collector includes at least a bag dust collector and at least one gas dust removal device. Therefore, when the blast furnace is in normal production or when the blast furnace is shut down, the system can achieve the full purification and recovery effect of the blast furnace gas, thereby meeting the gas purification and recovery needs under multiple working conditions during blast furnace operation.

[0029] A dust removal process for wind stop, comprising the following steps:

[0030] During blast furnace production: the bag filter is kept open according to traditional practices, the gas on-off valve and the main valve of the gas pipeline are opened at the same time, the on-off valve of the gas source pipe is closed, and the gas to be dedusted is injected into the dust removal tank through the gas pipeline and the gas inlet, the gas to be dedusted is discharged through the exhaust pipe after being dedusted by the filter bag, and the dust falling from the filter bag is collected by the ash discharge tank; and

[0031] When the blast furnace is shut down: detect the changes in the blast furnace top pressure and air volume, and the pressure in the dust removal tank. When the pressure drops to a preset range, open the gas source pipe on-off valve to introduce high-pressure gas source into the dust removal tank through the induced gas source inlet and the gas source pipe; at the same time, gradually close the bag filter to allow the coal gas to pass through the gas dust removal device, remove the dust from the blast furnace, the first pipeline, the primary dust removal, the second pipeline and the residual coal gas in the dust removal tank, and discharge it out of the dust removal tank to enter the downstream pipeline.

[0032] By adopting the above technical scheme, when the blast furnace is in normal production, this process can purify blast furnace gas like other blast furnace gas dust removal devices; when the blast furnace is shut down, this process can continue to operate. This process can be applied to different working conditions, and in practice the working mode can be switched through simple operations.

[0033] A coal gas full recovery process comprises the following steps:

[0034] Detecting the pressure in the blast furnace material tank, and when the pressure drops to a preset range, opening the gas source pipe on-off valve to introduce a high-pressure gas source into the dust removal tank through the ejector gas source inlet and the gas source pipe; recovering and dusting the residual gas in the blast furnace material tank and discharging it from the dust removal tank; and

[0035] The coal gas discharged through the dust removal tank is recovered.

[0036] By adopting the above technical solution, the advantages of the old process are retained, and the problems of the old process occupying a large area and making high noise are solved, making the system more perfect and more user-friendly.

[0037] In summary, the present application includes at least one of the following beneficial technical effects:

[0038] 1. Saves renovation work and floor space. It meets the gas purification and recovery requirements under multiple working conditions during blast furnace operation, improves the gas recovery rate in the wind-off state, reduces environmental pollution, and can well solve the noise problem of existing patents;

[0039] 2. The setting of the bypass air inlet pipe allows the gas dust removal device to be suitable for different working conditions of the blast furnace, thereby improving the applicability of the gas dust removal device;

[0040] 3. The combined use of the back-blowing pulse device and the wave-increasing funnel greatly improves the dust removal effect on the filter bag, thereby improving the durability of the gas dust removal device;

[0041] 4. The total filtering area of ​​the blast furnace gas dust removal device is increased, the filtering speed of the gas is reduced, and the service life of the filter bag is extended; the number of filter boxes is increased, which is conducive to improving the reliability of dry gas dust removal.

[0042] 5. When the blast furnace is operating normally, the gas dust removal device can also be used as an ordinary blast furnace gas dust collector, which improves the use efficiency of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the overall structure of Example 1 of the present application.

[0044] Figure 2 It is a schematic diagram of the structure of the bracket in Example 1 of the present application.

[0045] Figure 3 It is a structural schematic diagram of the wave-amplifying funnel in Example 1 of the present application.

[0046] Figure 4 It is a schematic diagram of the connection between the bracket and the ejector in Example 1 of the present application.

[0047] Figure 5It is a schematic diagram of the overall structure of Example 2 of the present application.

[0048] Figure 6 It is a schematic diagram of the overall structure of Example 3 of the present application.

[0049] Figure 7 It is a schematic diagram of the overall structure of Example 5 of the present application.

[0050] In the figure: 1. gas dust removal device; 11. dust removal tank; 12. filter bag; 13. ejector; 131. gas inlet; 132. ejector gas source inlet; 14. ash unloading tank; 141. upper ash unloading valve; 142. ash unloading port; 143. lower ash unloading valve; 144. vent pipe; 1441. vent pipe on-off valve; 15. exhaust pipe; 151. exhaust pipe on-off valve; 2. gas pipeline; 21. gas on-off valve; 22. gas pipeline main valve; 23. recovery valve; 3. gas source pipe; 31. gas source pipe on-off valve ; 4. Bypass air inlet pipe; 41. Air inlet on-off valve; 5. Pulse back-blowing device; 51. Air blowing pipe; 6. Bracket; 61. Through slot; 62. Wave-increasing funnel; 7. Blast furnace; 8. First pipeline; 9. Second pipeline; 10. Primary dust collector; 101. Secondary dust collector; 1011. Bag dust collector; 102. Gas pipeline network; 1021. Clean gas pipe; 1022. Gas residual pressure recovery device; 1023. Pressure reducing valve group; 1024. Low-pressure gas pipe; 103. Ash conveying pipe; 104. Blast furnace material tank. DETAILED DESCRIPTION

[0051] The following is combined with Figure 1-6 This application is described in further detail.

[0052] Example 1

[0053] The present application discloses a gas dust removal device. Figure 1 A gas dust removal device includes: a dust removal tank 11, a filter bag 12, an ejector 13 and an ash discharge tank 14.

[0054] Among them, the filter bag 12 is arranged in the dust removal tank 11, the ejector 13 is coaxially arranged with the dust removal tank 11, and the first end of the ejector 13 is located outside the dust removal tank 11, and the second end of the ejector 13 passes through the bottom of the filter bag 12 and is located in the dust removal tank 11. The first end of the ejector 13 is provided with a gas inlet 131 and an ejection gas source inlet 132, and the gas inlet 131 is connected to the gas pipeline 2, and one end of the gas pipeline 2 is connected to the blast furnace 7. The gas pipeline 2 is provided with a gas on-off valve 21 and a gas pipeline main valve 22, and the dust-removed gas can be injected into the dust removal tank 11 through the gas pipeline 2 and the gas inlet 131. In this embodiment, the gas pipeline main valve 22 may not be provided according to actual conditions, and in this embodiment, the gas pipeline main valve 22 is preferably provided.

[0055] In addition, the ejector gas source inlet 132 is connected to the gas source pipe 3, the extension direction of the gas source pipe 3 is perpendicular to the axial extension direction of the ejector 13, and a gas source pipe on-off valve 31 is provided on the gas source pipe 3. The gas source connected to the gas source pipe 3 can be clean gas such as coal gas, nitrogen, steam, etc.

[0056] An exhaust pipe 15 is connected to the side wall of the dust removal tank 11 and above the filter bag 12 . An exhaust pipe on-off valve 151 is provided on the exhaust pipe 15 . The dust-removed gas is discharged through the exhaust pipe 15 after being dust-removed by the filter bag 12 .

[0057] A pulse back-blowing device 5 is also connected to the side wall of the dust removal tank 11, and an air blowing pipe 51 is connected between the pulse back-blowing device 5 and the dust removal tank 11, and the inlet of the air blowing pipe 51 is located above the filter bag 12. The pulse back-blowing device 5 can blow off the dust deposited on the filter bag 12 so as to restore the dust removal effect of the filter bag 12.

[0058] The bottom side of the dust removal tank 11 is connected with a bypass air inlet pipe 4, the air inlet of the bypass air inlet pipe 4 is connected with the gas pipeline 2, the air outlet of the bypass air inlet pipe 4 is located below the filter bag 12, and an air inlet on-off valve 41 is provided on the bypass air inlet pipe 4. The air inlet on-off valve 41 can be a butterfly valve, a cut-off valve, a check valve or a valve group, etc. When the pressure in the blast furnace 7 is relatively high, the air inlet on-off valve 41 on the bypass air inlet pipe 4 is opened to increase the amount of gas entering the dust removal tank 11 and improve the ventilation efficiency; in addition, the gas on-off valve 21 can be closed to close the ejector 13 channel to reduce the amount of dust in the ejector 13 pipeline, thereby avoiding the blockage of the gas source pipe 3 as much as possible.

[0059] Finally, the dust discharge tank 14 is connected to the bottom of the dust removal tank 11 to collect dust falling from the filter bag 12. An upper dust discharge valve 141 is provided at the connection between the dust discharge tank 14 and the dust removal tank 11. An dust discharge port 142 is provided at the bottom of the dust discharge tank 14, and a lower dust discharge valve 143 is provided at the dust discharge port 142.

[0060] A vent pipe 144 is connected to the side wall of the ash unloading tank 14 , and a vent pipe on-off valve 1441 is provided on the vent pipe 144 .

[0061] To sum up, the ejector 13, the ash discharge tank 14 and the filter bag 12 are all installed on the dust removal tank 11. The gas dust removal device provided by the present application uses the same space as the existing bag dust collector, avoiding the need for independent pipes, equipment supports, valve operating platforms and other equipment facilities for the ejector, reducing the equipment's footprint, simplifying external ancillary facilities, and facilitating the reasonable layout of the equipment under conditions of tight space layout.

[0062] In addition, since the gas pipeline originally arranged in the center of the dust removal tank 11 is replaced by an ejector, the ejector and the dust collector are cleverly integrated into one device, and the dust collector shell is used as the huge shell of the ejector, and there is a filter bag 12 inside to filter the dust, a sound insulation cover of the ejector 13 is naturally formed, which seals the huge noise generated by the ejector 13 when it is working inside the dust removal tank 11, greatly reducing the noise pollution around the equipment, which is beneficial to improving the working environment of on-site staff and is beneficial to occupational health.

[0063] Reference Figure 1 In order to further reduce the noise volume generated by the ejector 13 when it is working, the upper end of the dust removal tank 11 is located at the constriction of the ejector 13. The entire dust removal tank 11 wraps the constriction of the ejector 13 to prevent the noise at the constriction from propagating outward.

[0064] In addition, refer to Figure 1 and Figure 2 , a plurality of brackets 6 are filled between the ejector 13 and the inner wall of the dust removal tank 11. The cross-sectional shape of the bracket can be square, rectangular, rhombus, etc., and is preferably circular in this embodiment. A plurality of through slots 61 are provided on the side wall of the bracket 6. The filter bag is sleeved on the bracket, and the filter bag abuts against the outer peripheral wall of the bracket.

[0065] Reference Figure 3 , a plurality of brackets 6 are arranged crosswise with each other, and the filter bag 12 wraps the bracket 6. A plurality of brackets 6 are arranged crosswise with each other, thereby bending the propagation path of the noise, so that the sound waves of the noise slowly dissipate between the plurality of brackets 6, thereby further reducing the noise volume generated when the ejector 13 is working.

[0066] Reference Figure 2 and Figure 4 In order to enhance the dust removal effect of the pulse back-blowing device 5 on the filter bag 12, a wave-increasing funnel 62 is provided at one end of the bracket 6 near the air blowing pipe 51 and in the middle part of the bracket 6. The wave-increasing funnel 62 is a tubular body with wide ends and narrow in the middle. When the air wave blown out from the air blowing pipe 51 enters from one end of the wave-increasing funnel 62, since the middle of the wave-increasing funnel 62 is narrow, the air wave is compressed to a certain extent in the narrow part, and then the air wave reaches the wide mouth at the other end of the wave-increasing funnel 62, the flow speed of the air wave is accelerated, and part of the air wave is dispersed along the surroundings, thereby passing through the through slot 61 on the bracket 6 and blowing toward the filter bag 12. The blowing direction of the air wave forms a certain angle with the filter bag 12, and the air wave is blown from the inner edge of the filter bag 12 to the filter bag 12, so that the air wave is relatively easier to blow off the dust on the filter bag 12.

[0067] In addition, the energy of the air wave will decrease relatively as it moves, so the wave-enhancing funnel 62 arranged in the middle part of the bracket 6 once again enhances the energy of the air wave, thereby blowing off the dust on the part of the filter bag 12 that is relatively far away from the air blowing pipe 51, so as to further enhance the dust removal effect on the filter bag 12.

[0068] Example 2, please refer to Figure 5 The difference between this embodiment and embodiment 1 is that the position of the gas source pipe 3 is different, and the extension direction of the gas source pipe 3 is in the same direction as the axial extension direction of the ejector 13.

[0069] When the gas source pipe on-off valve 31 is opened, the gas in the gas source pipe 3 is directly ejected from the ejector gas source inlet 132 along the axial extension direction of the ejector 13 into the dust removal tank 11. Therefore, the air flow speed in the ejector 13 is relatively fast, so that the dust removal efficiency of the gas dust removal device 1 is relatively higher and the dust removal effect is relatively better.

[0070] Example 3

[0071] The present application discloses a blast furnace gas dry dust removal system. Figure 6 The blast furnace gas dry dust removal system includes: a blast furnace 7, a primary dust collector 10, a secondary dust collector 101, and a gas pipeline network 102.

[0072] The blast furnace 7 is used for smelting. The coal gas generated by the blast furnace during smelting contains combustible gas components such as carbon monoxide that can be utilized, and needs to be dedusted in sequence through multi-stage dust collectors.

[0073] The primary dust collector 10 is connected to the output port of the blast furnace 7 through the first pipeline 8. The primary dust collector in this embodiment can be a gravity dust collector, an inertial dust collector, a cyclone dust collector, a filter dust collector, a wet dust collector, etc. The primary dust collector 10 is mainly used for preliminary dust removal of large particles in the coal gas.

[0074] The secondary dust collector 101 is connected to the output port of the blast furnace 7 through the second pipeline 9. The secondary dust collector 101 is mainly used to further remove dust from the coal gas that has undergone preliminary dust removal to improve the dust removal effect. Among them, the secondary dust collector 101 includes at least one coal gas dust removal device 1, which is a dust collector with an ejector 13 and a gas source pipe 3, and the other secondary dust collectors 101 are bag dust collectors 1011 without ejectors 13 and gas source pipes 3; the number of coal gas dust removal devices 1 and bag dust collectors 1011 to be opened can be determined according to the amount of coal gas generated by the blast furnace to adapt to different states when the blast furnace is working. Moreover, the bag dust collector 1011 can be a top-in and top-out structure, a bottom-in and top-out structure, and other structures.

[0075] The gas pipeline network 102 receives the gas exhausted from the secondary dust collector 101 so as to recover the recyclable gas.

[0076] Among them, the number of secondary dust collectors 101 can be determined according to the specific situation, and multiple secondary dust collectors 101 are connected in parallel or in series through pipelines; in addition, an ash conveying pipe 103 is arranged under the secondary dust collector 101, and each ash unloading tank 14 of the secondary dust collector 101 is connected to the ash conveying pipe 103.

[0077] When the ash unloading tank 14 is unloading ash, close the upper ash unloading valve 141, open the on-off valve of the dispersion pipe 144 and the lower ash unloading valve 143, so that the dust in the tank is discharged to the ash conveying pipe 103 through the ash unloading port 142. Then the discharged dust can be transported away by vehicles for recycling after passing through the humidifying ash unloading machine, or it can be directly collected by a closed tank truck and recycled for reuse. It can also be collected and concentrated in the large ash plant of the dry dust removal system for centralized treatment. At the same time, according to actual needs, the ash conveying pipe 103 may not be set below the secondary dust collector 101, or other ash receiving devices may be set.

[0078] Finally, the gas pipeline network 102 includes a clean gas pipe 1021, a gas residual pressure recovery device 1022 (TR or BPRT), a pressure reducing valve group 1023 and a low-pressure gas pipe 1024. The exhaust pipes 15 on the dust collector are connected to the clean gas pipe 1021, and the clean gas pipe 1021, the gas residual pressure recovery device 1022 and the low-pressure gas pipe 1024 are connected in sequence. The pressure reducing valve group 1023 is connected in parallel with the gas residual pressure recovery device 1022. The pressure reducing valve group 1023 can reduce the pressure of the recovered gas for subsequent use.

[0079] When the blast furnace 7 is in the wind-off operation state, the changes in the pressure and air volume at the top of the blast furnace 7 are detected. When the pressure and air volume drop to a preset range, the gas source pipe on-off valve 31 is opened to introduce a high-pressure gas source into the dust removal tank 11 through the induced gas source inlet 132 and the gas source pipe 3. At the same time, the bag filter 1011 is gradually closed to allow the coal gas to pass through the gas dust removal device 1, and the residual coal gas from the blast furnace 7, the first pipeline 8, the primary dust collector 10, and the second pipeline 9 is dusted and discharged from the dust removal tank 11. After filtering and purification, the coal gas is transported to the gas pipeline network 102, thereby realizing the purification and recovery of the blast furnace wind-off coal gas.

[0080] The system in this embodiment increases the area of ​​the filter bag 12 of the entire system by setting a primary dust collector 10 and a secondary dust collector 101, thereby increasing the total filtering area of ​​the blast furnace gas dust removal device 1. The increase in the number of filter bags 12 reduces the filtering speed of the gas and extends the service life of the filter bags 12. At the same time, the system increases the number of filter boxes and improves the reliability of dry dust removal of gas. Moreover, the system meets the gas purification and recovery requirements under multiple working conditions during the operation of the blast furnace 7, improves the gas recovery rate in the wind-off state, and reduces environmental pollution.

[0081] The implementation principle of a blast furnace gas dry dust removal system in the embodiment of the present application is as follows: when the blast furnace 7 is in normal production, the bag filter 1011 is kept open according to traditional practices, and the gas on-off valve 21 and the main valve 22 of the gas pipeline 2 are opened, and the on-off valve 31 of the gas source pipe is closed, and the gas is injected into the ejector 13 from the gas pipeline 2 and the gas inlet 131, and then enters the bottom of the dust removal tank 11 along the ejector 13. Then the gas rises from the bottom of the dust removal tank 11 through the filter bag 12, and the filter bag 12 filters the gas, and the filtered gas is discharged from the dust removal tank 11 along the exhaust pipe 15 above the dust removal tank 11. The filtered dust is collected by another device according to actual needs. In addition, when the gas volume of the blast furnace 7 is large, the air intake on-off valve 41 on the bypass air intake pipe 4 is opened, and the gas directly enters the bottom of the dust removal tank 11 from the bypass air intake pipe 4 to improve the ventilation efficiency; and the ejector 13 channel can be closed through the gas on-off valve 21 to reduce the amount of dust in the ejector 13 pipeline, thereby avoiding the blockage of the gas source pipe 3 as much as possible. In this state, the ejector 13 is only used as a pipeline for transporting blast furnace gas, so that the gas pipeline 2 and the gas inlet 131 can smoothly enter the dust removal tank 11.

[0082] When the blast furnace 7 is in the wind-off operation state, the changes in the pressure and air volume of the top of the blast furnace 7 are detected. When the pressure and air volume drop to the preset range, the gas source pipe on-off valve 31 is opened to introduce the high-pressure gas source into the dust removal tank 11 through the induced gas source inlet 132 and the gas source pipe 3, and the bag dust collector 1011 is gradually closed at the same time, so that the coal gas passes through the gas dust removal device 1, and the residual coal gas of the blast furnace 7, the first pipeline 8, the primary dust collector 10, and the second pipeline 9 is dusted and discharged from the dust removal tank 11. In this state, the ejector 13 uses its ejection function, the purpose of which is to eject the high-pressure gas source into the dust removal tank, and the high-pressure coal gas is sprayed inside the ejector through the nozzle to form a negative pressure, and the residual coal gas in the blast furnace 7, the first pipeline 8, the primary dust collector 10, and the second pipeline 9 is forcibly recovered, so as to achieve full recovery of the coal gas released during wind-off.

[0083] This technology solves the problem that the old technology cannot achieve the treatment of the vented gas during the shutdown process, and at the same time realizes the full recovery of the vented gas during the shutdown process of blast furnace 7, and there is no longer the pollution problem of direct emission of the vented gas into the air.

[0084] Example 4

[0085] The present application discloses a dust removal process for wind stop, comprising the following steps:

[0086] During blast furnace production: the bag filter 1011 is kept open according to traditional practices, the gas on-off valve 21 and the main valve 22 of the gas pipeline are opened, the gas source pipe on-off valve 31 is closed, and the dedusted gas is injected into the dedusting tank 11 through the gas pipeline 2 and the gas inlet 131, and the dedusted gas is discharged through the exhaust pipe 15 after being dedusted by the filter bag 12, and the dust falling from the filter bag 12 is collected by the ash unloading tank 14; and

[0087] When the blast furnace 7 is shut down: detect the changes in the pressure and air volume at the top of the blast furnace 7 and the pressure in the dust removal tank 11. When the pressure drops to a preset range, open the gas source pipe on-off valve 31 to introduce high-pressure gas into the dust removal tank 11 through the induced gas source inlet 132 and the gas source pipe 3; at the same time, gradually close the bag filter 1011 to allow the coal gas to pass through the gas dust removal device 1, and remove the dust from the residual coal gas in the blast furnace 7, the first pipeline 8, the primary dust collector 10, the second pipeline 9 and the dust removal tank 11, and then discharge it from the dust removal tank 11 to enter the downstream pipeline.

[0088] In summary, the coal gas dust removal device 1, the wind-off dust removal system and the wind-off dust removal process provided by the present application are provided with an ejector 13 in the dust removal tank 11. When the blast furnace 7 is in normal production, it can purify the blast furnace gas like other bag dust collectors 1011; when the blast furnace 7 is in wind-off operation, the system can continue to operate, and the process can be applied to different working conditions, and in practice the working mode can be switched through simple operations; and the high-pressure gas source can be coal gas, nitrogen, steam, etc., and has a wide range of applications.

[0089] Example 5

[0090] Reference Figure 7 This embodiment discloses a gas full recovery process, which specifically includes the following steps:

[0091] Step S1: Detect the pressure in the blast furnace material tank 104, and when the pressure drops to a preset range, open the gas source pipe on-off valve 31 to introduce a high-pressure gas source into the dust removal tank 11 through the induced gas source inlet 132 and the gas source pipe 3; recover and dedust the residual coal gas in the dust removal tank 11 and discharge it from the dust removal tank 11.

[0092] Step S2: using the gas pipeline network 102 in Example 4 to recover the gas discharged through the dust removal tank 11.

[0093] The blast furnace charge tank 104 is a device used in conjunction with the blast furnace 7, and is mainly used to deliver materials to the blast furnace. When the blast furnace 7 is in production, the pressure in the blast furnace 7 needs to be the same as the pressure in the blast furnace charge tank 104, so there will be a certain amount of gas in the blast furnace charge tank 104, and the gas in the blast furnace charge tank 104 can also be recovered through the above process.

[0094] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A gas dust removal device, characterized in that: include: A dust removal tank (11), a filter bag (12), an ejector (13) and an ash discharge tank (14), wherein the filter bag (12) is arranged in the dust removal tank (11), the ejector (13) is arranged along the axial direction of the dust removal tank (11), and the first end of the ejector (13) is located outside the dust removal tank (11), the second end of the ejector (13) passes through the bottom of the filter bag (12) and is located in the dust removal tank (11), the first end of the ejector (13) is provided with a gas inlet (131) and an ejection gas source inlet (132), the gas inlet (131) is connected to a gas pipeline (2), and the gas pipeline (2) is provided with a gas inlet (132). The gas to be dedusted is provided with a shut-off valve (21) and a main valve (22) of a gas pipeline, and the gas to be dedusted can be injected into the dust removal tank (11) through the gas pipeline (2), the gas inlet (131) and the ejector (13); the ejector gas source inlet (132) is connected to the gas source pipe (3), and the gas source pipe (3) is provided with a gas source pipe on-off valve (31); an exhaust pipe (15) is connected to the side wall of the dust removal tank (11) and above the filter bag (12), and the gas to be dedusted is discharged through the exhaust pipe (15) after being dedusted by the filter bag (12); the dust discharge tank (14) is connected to the bottom of the dust removal tank (11) to collect dust falling from the filter bag (12); The upper end of the dust removal tank (11) is located at the constricted opening of the ejector (13); The bottom side of the dust removal tank (11) is connected to a bypass air inlet pipe (4), the air inlet of the bypass air inlet pipe (4) is connected to the gas pipeline (2), the air outlet of the bypass air inlet pipe (4) is located below the filter bag (12), and the bypass air inlet pipe (4) is provided with an air inlet on-off valve (41).

2. A gas dust removal device according to claim 1, characterized in that: The extension direction of the gas source pipe (3) is perpendicular to the axial extension direction of the ejector (13).

3. A gas dust removal device according to claim 1, characterized in that: The extension direction of the gas source pipe (3) is in the same direction as the axial extension direction of the ejector (13).

4. A gas dust removal device according to any one of claims 1 to 3, characterized in that: The side wall of the dust removal tank (11) is connected to a pulse back-blowing device (5), an air blowing pipe (51) is connected between the pulse back-blowing device (5) and the dust removal tank (11), and the inlet of the air blowing pipe (51) is located above the filter bag (12).

5. A gas dust removal device according to claim 1, characterized in that: A plurality of brackets (6) are filled between the ejector (13) and the inner wall of the dust removal tank (11), the plurality of brackets (6) are arranged crosswise with each other, and the filter bag (12) wraps the brackets (6); and One end of the bracket (6) faces the inlet of the air blowing pipe (51), and a wave-enhancing funnel (62) is provided at one end of the bracket (6) close to the air blowing pipe (51) and at the middle part of the bracket (6).

6. A blast furnace gas dry dust removal system, characterized in that: include: Blast furnace (7); A primary dust collector (10) is connected to the output port of the blast furnace (7) through a first pipeline (8); A secondary dust collector (101) is connected to the output port of the primary dust collector (10) via a second pipe (9), wherein the secondary dust collector (101) comprises at least a bag dust collector (1011) and at least one coal gas dust removal device (1), wherein the coal gas dust removal device (1) is the coal gas dust removal device (1) according to any one of claims 1 to 5; and The gas pipe network (102) receives the gas discharged from the gas dust removal device (1) and the bag filter (1011).

7. A wind-stop dust removal process, characterized in that: A blast furnace gas dry dust removal system is provided as claimed in claim 6, and comprises the following steps: When the blast furnace (7) is in production: the bag filter (1011) is kept in an open state according to traditional practices, the gas on-off valve (21) and the main valve (22) of the gas pipeline are opened at the same time, the on-off valve of the gas source pipe (3) is closed, and the dedusted gas can be injected into the dedusting tank (11) through the gas pipeline (2) and the gas inlet (131), the dedusted gas is dedusted by the filter bag (12) and then discharged through the exhaust pipe (15), and the dust falling from the filter bag (12) is collected by the ash discharge tank (14); and When the blast furnace (7) is shut down: the pressure and air volume of the top of the blast furnace (7) and the changes in the pressure in the dust removal tank (11) are detected. When the pressure drops to a preset range, the on-off valve of the gas source pipe (3) is opened to introduce a high-pressure gas source into the dust removal tank (11) through the induced gas source inlet (132) and the gas source pipe (3); at the same time, the bag filter (1011) is gradually closed to allow the coal gas to pass through the coal gas dust removal device (1), and the residual coal gas in the blast furnace (7), the first pipeline (8), the primary dust collector (10), the second pipeline (9) and the dust removal tank (11) is dusted and discharged from the dust removal tank (11) to enter the downstream pipeline.

8. A coal gas full recovery process, characterized in that: A coal gas dust removal device according to any one of claims 1 to 5 is provided, and comprises the following steps: Detecting the pressure in the blast furnace material tank (104), and when the pressure drops to a preset range, opening the on-off valve of the gas source pipe (3) to introduce a high-pressure gas source into the dust removal tank (11) through the ejector gas source inlet (132) of the ejector (13) and the gas source pipe (3); recovering and removing dust from the residual coal gas in the blast furnace material tank (104) and discharging it from the dust removal tank (11); and The coal gas discharged through the dust removal tank (11) is recovered.

Images