CN220393775U - Blast furnace gas recovery system - Google Patents
Blast furnace gas recovery system Download PDFInfo
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- CN220393775U CN220393775U CN202320983418.3U CN202320983418U CN220393775U CN 220393775 U CN220393775 U CN 220393775U CN 202320983418 U CN202320983418 U CN 202320983418U CN 220393775 U CN220393775 U CN 220393775U
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- gas recovery
- pressure relief
- pipe
- dust remover
- blast furnace
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- 238000011084 recovery Methods 0.000 title claims abstract description 85
- 239000000428 dust Substances 0.000 claims abstract description 120
- 230000007246 mechanism Effects 0.000 claims abstract description 22
- 239000004744 fabric Substances 0.000 claims abstract description 11
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 11
- 239000012530 fluid Substances 0.000 claims abstract description 5
- 238000013016 damping Methods 0.000 claims description 36
- 239000003034 coal gas Substances 0.000 claims description 6
- 230000001174 ascending effect Effects 0.000 claims description 4
- 238000012423 maintenance Methods 0.000 abstract description 6
- 239000007789 gas Substances 0.000 description 116
- 239000003638 chemical reducing agent Substances 0.000 description 8
- 230000000630 rising effect Effects 0.000 description 4
- 238000005452 bending Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 230000003749 cleanliness Effects 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000002787 reinforcement Effects 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Blast Furnaces (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
Abstract
The utility model relates to a blast furnace gas recovery system, which comprises a gas recovery main pipeline and a damping-down gas recovery branch pipeline, wherein a coarse dust remover and a first cloth bag dust remover are sequentially arranged on the gas recovery main pipeline, a damping-down gas recovery valve, a branch dust removing mechanism and an ejector are sequentially arranged on the damping-down gas recovery branch pipeline, the ejector is connected with a working fluid pipe, a pressure relief opening of the first cloth bag dust remover is connected with a first pressure relief pipe and is provided with a pressure relief valve, the first pressure relief pipe is connected with the damping-down gas recovery branch pipeline in a bypass mode, and a bypass point is positioned at the upstream of the ejector. According to the utility model, the pressure relief operation in the first bag-type dust collector can be completed through the ejector, so that the gas in the first bag-type dust collector can be fully recovered and discharged, the pressure relief efficiency can be greatly improved, and the maintenance time of the first bag-type dust collector can be shortened.
Description
Technical Field
The utility model relates to a blast furnace gas recovery system.
Background
In the production process of the blast furnace, the blast furnace needs to be periodically subjected to damping-down maintenance, and the damping-down is mainly realized by cutting off the blast furnace body and the gas system and communicating the blast furnace body with the atmosphere, and meanwhile, the blower, the hot blast furnace system and the blast furnace gas system are disconnected; because the blast furnace is isolated from surrounding systems and is in a production stop state, commonly called damping down, the blast furnace is convenient to deliver and overhaul. When the damping down and releasing the gas are started, the damping down gas is directly passed through a dry gas dust removal system by utilizing the advantage of higher pressure of the top gas, and the part of gas is recovered after being purified by the system and enters a clean gas pipe network. When the pressure of the top gas is lower than 30-40 kpa, the processing speed of the dry gas dust removing system is very slow and becomes difficult, in order to smoothly break down the wind, a cut-off valve between the blast furnace crude gas system and the dry gas dust removing system is generally closed, the gas in the furnace is directly diffused into the atmosphere at the top of the blast furnace and the top of a gravity dust remover, and the diffused gas is shown as a large amount of yellow brown smoke dust, and has high carbon monoxide content and large emission noise, thus influencing the environment; and the CO contained in the partial gas has a certain utilization value, and the CO is diffused into the air to cause the waste of resources. In addition, some enterprises are provided with a damping-down gas recovery pipeline so as to recover damping-down gas, and the ejector can improve the damping-down gas recovery efficiency and shorten the damping-down time.
The blast furnace gas dry dust removal is used as a mature dust removal process for most blast furnaces in China, and a cloth bag dust remover is common dry dust removal equipment. In the running process of the bag-type dust remover, the back-blowing dust removing operation is required to be carried out periodically or irregularly, and before back-blowing dust removing, the pressure releasing operation is required to be carried out on the dust remover; in the pressure relief process, along with the reduction of the pressure in the dust remover, the pressure relief speed can be slowed down, so that the pressure relief time is longer, and accordingly, the maintenance time of the bag-type dust remover can be increased, and the normal operation of a blast furnace gas recovery system is influenced.
Disclosure of Invention
The utility model relates to a blast furnace gas recovery system which at least can solve part of defects in the prior art.
The utility model relates to a blast furnace gas recovery system which comprises a gas recovery main pipeline and a damping down gas recovery branch pipeline, wherein a coarse dust remover and a first cloth bag dust remover are sequentially arranged on the gas recovery main pipeline, a damping down gas recovery valve, a branch dust removing mechanism and an ejector are sequentially arranged on the damping down gas recovery branch pipeline, the ejector is connected with a working fluid pipe, a pressure relief opening of the first cloth bag dust remover is connected with a first pressure relief pipe, a pressure relief valve is arranged on the first pressure relief pipe, and the first pressure relief pipe is connected with the damping down gas recovery branch pipeline and a side joint is positioned at the upstream of the ejector.
As one of the implementation manners, the bypass point of the first pressure relief pipe is located at the upstream of the branch dust removing mechanism, and the first pressure relief pipe is connected to the high-pressure side of the first bag-type dust remover.
As one of the implementation modes, the bypass point of the first pressure relief pipe is positioned between the branch dust removing mechanism and the ejector, and the first pressure relief pipe is connected to the low pressure side of the first bag-type dust remover.
As one of the implementation modes, the inlet end of the damping down gas recovery branch is connected to the gas recovery main pipeline in a bypass mode, and the bypass point is located between the coarse dust remover and the first bag-type dust remover.
As one of the implementation manners, the branch dust removing mechanism comprises a second bag-type dust remover.
As one of the implementation modes, the pressure relief opening of the second bag-type dust collector is connected with a second pressure relief pipe, a second pressure relief valve is arranged on the second pressure relief pipe, the second pressure relief pipe is connected to the damping down coal gas recovery branch road, and the bypass point is located between the branch road dust collection mechanism and the ejector.
As one implementation mode, the damping down gas recovery branch is also provided with a pressure reducing valve, and the pressure reducing valve is positioned at the downstream of the ejector.
As one of the implementation modes, the gas recovery main pipeline comprises a gas rising pipe, a gas falling pipe and a gas treatment pipe which are sequentially connected, wherein the gas rising pipe is connected with a blast furnace, and the coarse dust remover and the first cloth bag dust remover are respectively arranged on the gas treatment pipe.
As one embodiment, the coarse dust collector is a cyclone dust collector.
The utility model has at least the following beneficial effects:
according to the blast furnace gas recovery system provided by the utility model, the first pressure relief pipe of the first bag-type dust collector is connected to the damping-down gas recovery branch, and when the first bag-type dust collector needs to relieve pressure, the pressure relief operation can be carried out through the damping-down gas recovery branch, so that the pressure relief gas in the first bag-type dust collector can be recovered; because the side contact point of the first pressure relief pipe is positioned at the upstream of the ejector, the pressure relief operation in the first bag-type dust collector can be completed through the ejector in an auxiliary way, the coal gas in the first bag-type dust collector can be fully recovered and discharged, the pressure relief efficiency can be greatly improved, and the maintenance time of the first bag-type dust collector is shortened.
Drawings
In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIGS. 1 to 4 are schematic structural views of a blast furnace gas recovery system according to a first embodiment of the present utility model; wherein,
in fig. 1, a damping down gas recovery branch is connected between a coarse dust remover and a first bag-type dust remover, and a first pressure relief pipe is connected to the low pressure side of the first bag-type dust remover;
in fig. 2, a damping down gas recovery branch is connected between the coarse dust remover and the first bag-type dust remover, and a first pressure relief pipe is connected to the high pressure side of the first bag-type dust remover;
in fig. 3, a damping down gas recovery branch is connected at a connecting node of a gas rising pipe and a gas falling pipe, and a first pressure relief pipe is connected to the low pressure side of a first bag-type dust remover;
in fig. 4, a damping down gas recovery branch is connected at a connecting node of a gas rising pipe and a gas falling pipe, and a first pressure relief pipe is connected to the high pressure side of a first bag-type dust remover;
fig. 5 is a schematic structural diagram of a cyclone dust collector according to a second embodiment of the present utility model.
Detailed Description
The following description of the embodiments of the present utility model will be made clearly and completely, and it is apparent that the described embodiments are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
Example 1
As shown in fig. 1-4, an embodiment of the present utility model provides a blast furnace gas recovery system, including a gas recovery main pipeline and a damping down gas recovery branch pipeline 21, a coarse dust remover 14 and a first bag-type dust remover 15 are sequentially disposed on the gas recovery main pipeline, a damping down gas recovery valve 23, a branch dust removing mechanism and an ejector 22 are sequentially disposed on the damping down gas recovery branch pipeline 21, the ejector 22 is connected with a working fluid pipe, a pressure relief opening of the first bag-type dust remover 15 is connected with a first pressure relief pipe 151, a pressure relief valve is disposed on the first pressure relief pipe 151, the first pressure relief pipe 151 is connected to the damping down gas recovery branch pipeline 21 in a bypass manner, and a bypass point is located upstream of the ejector 22.
Preferably, as shown in fig. 1-4, the main gas recovery pipeline comprises a gas ascending pipe 11, a gas descending pipe 12 and a gas treatment pipe 13 which are sequentially connected, wherein the gas ascending pipe 11 is connected with a blast furnace, and the coarse dust remover 14 and the first cloth bag dust remover 15 are respectively arranged on the gas treatment pipe 13.
The main gas recovery pipeline is generally connected with the clean gas pipe network 3, and the gas treatment pipe 13 is connected with the clean gas pipe network 3; the above-mentioned damping down gas recovery branch 21 is also preferably connected to the net gas pipe network 3.
Further, a top large bleed valve is provided at the top of the gas riser 11.
The coarse dust collector 14 may be a cyclone dust collector, a gravity dust collector, or the like.
In one embodiment, as shown in fig. 1 and 3, the bypass point of the first pressure relief pipe 151 is located between the bypass dust removing mechanism and the ejector 22, and the first pressure relief pipe 151 is connected to the low pressure side of the first bag-type dust collector 15. In another embodiment, as shown in fig. 2 and 4, the bypass point of the first pressure relief pipe 151 is located upstream of the bypass dust removing mechanism, the first pressure relief pipe 151 is connected to the high pressure side of the first bag-type dust collector 15, and the gas discharged from the high pressure side can be processed by the bypass dust removing mechanism, so that the cleanliness of the gas can be ensured.
In one embodiment, as shown in fig. 1 and 2, the inlet end of the damping down gas recovery branch 21 is connected to the gas recovery main pipeline and the bypass point is located between the coarse dust remover 14 and the first bag-type dust remover 15, so that the coarse dust remover 14 on the gas recovery main pipeline can be shared during damping down gas recovery. Further, the bypass dust removing mechanism adopts a cloth bag dust remover, namely the bypass dust removing mechanism comprises a second cloth bag dust remover 24, so that the cleanliness of damping down gas entering the clean gas pipe network 3 can be ensured.
In further embodiments, as shown in fig. 3 and 4, the inlet end of the damping down gas recovery branch 21 is bypassed on the gas riser 11 or the gas downcomer 12 or at the connection node of the gas riser 11 and the gas downcomer 12. In this solution, preferably, the bypass dust removing mechanism includes a first dust remover 26 and a second dust remover 24, where the first dust remover 26 uses coarse dust removing equipment such as a cyclone dust remover, and the second dust remover uses fine dust removing equipment such as the second bag dust remover 24.
Preferably, the damping down gas recovery branch 21 is further provided with a pressure reducing valve 25, and the pressure reducing valve 25 is located at the downstream of the ejector 22, so that the gas pressure at the outlet of the damping down gas recovery branch 21 can be reduced to a reasonable range, and the impact on the clean gas pipe network 3 is reduced.
The injection gas used in the ejector 22 may be nitrogen, gas, etc., and the working fluid pipe thereof may be connected to a corresponding gas source.
In the blast furnace gas recovery system provided by the embodiment, the first pressure relief pipe 151 of the first bag-type dust collector 15 is connected to the damping-down gas recovery branch 21, and when the first bag-type dust collector 15 needs to relieve pressure, the pressure relief operation can be performed through the damping-down gas recovery branch 21, so that the pressure relief gas in the first bag-type dust collector 15 can be recovered; because the bypass contact point of the first pressure relief pipe 151 is positioned at the upstream of the ejector 22, the pressure relief operation in the first bag-type dust collector 15 can be completed by the aid of the ejector 22, so that the gas in the first bag-type dust collector 15 can be fully recovered and discharged, the pressure relief efficiency can be greatly improved, and the maintenance time of the first bag-type dust collector 15 can be shortened.
Wherein, can set up the auxiliary control valve on damping down gas recovery branch road 21, this auxiliary control valve is located between the bypass point of first pressure release pipe 151 and the branch road dust removal mechanism, can carry out the control of pressure release injection operation better.
For the case that the bypass dust removing mechanism includes the second bag-type dust remover 24, preferably, the pressure relief opening of the second bag-type dust remover 24 is connected with a second pressure relief pipe and a second pressure relief valve is arranged on the second pressure relief pipe, the second pressure relief pipe is connected to the damping down gas recovery bypass 21, and the bypass point is located between the bypass dust removing mechanism and the ejector 22. Based on the structure, the pressure relief operation in the second bag-type dust collector 24 can be completed through the ejector 22 in an auxiliary manner, so that the gas in the second bag-type dust collector 24 can be fully recovered and discharged, the pressure relief efficiency can be greatly improved, and the maintenance time of the second bag-type dust collector 24 can be shortened.
In one embodiment, as shown in fig. 1-4, the blast furnace gas recovery system further comprises a equalizing gas recovery pipe 41 connected with the charging bucket 4, wherein an equalizing gas recovery valve is arranged on the equalizing gas recovery pipe 41, and the equalizing gas recovery pipe 41 is connected to the main gas recovery pipeline by-pass and the by-pass point is positioned at the upstream of the coarse dust remover 14, or connected to the damping gas recovery branch 21 by-pass and the by-pass point is positioned at the upstream of the branch dust removing mechanism. In the solution shown in fig. 1 and 2, the equalizing gas recovery pipe 41 is by-passed to the gas riser 11. Therefore, the system can realize the recovery of blast furnace damping down gas and charging bucket equalizing gas.
Example two
The present embodiment provides a cyclone 14 for a blast furnace, which can be used in the first embodiment described above as the coarse dust collector 14 therein.
The tangential inlet pipe 141 of the cyclone dust collector 14 is connected with the gas falling pipe 12 through a reducing pipe 142, and the cross-sectional area of the reducing pipe 142 is gradually reduced from the gas falling pipe 12 to the tangential inlet pipe 141; preferably, as shown in fig. 5, the outer sleeve 143 is sleeved outside the reducer pipe 142, and the outer sleeve 1433 and the reducer pipe 1422 form a double-layer pipeline structure, wherein one end of the outer sleeve 143 is fixedly connected to the gas downcomer 12, and the other end extends to be connected to the tangential inlet pipe 141.
By coating the outer sleeve 143 on the reducer pipe 142, the structural stability of the reducer pipe 142 can be effectively improved.
Further, both ends of the outer sleeve 143 are sealed, that is, the joint between the outer sleeve 143 and the gas descending pipe 12 and the joint between the outer sleeve 143 and the tangential inlet pipe 141 are sealed, so that the space between the outer sleeve 143 and the reducer pipe 142 is a closed space, and raw gas can be prevented from entering the space between the outer sleeve 143 and the reducer pipe 142.
In this embodiment, the outer sleeve 143 includes a main body portion and a bending portion that are disposed in an up-down distribution manner, the main body portion is disposed in an inclined manner, the bending portion is disposed horizontally, and a reinforcement ring is sleeved outside the bending portion, so that the assembly stability and the sealing effect between the outer sleeve 143 and the reducer pipe 142 can be further enhanced.
In this embodiment, the bottom of the reinforcement ring is connected with a supporting frame 144 for forming a supporting fit with the ground, so that the outer sleeve 143 and the reducer pipe 142 form a reliable and stable support.
The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the utility model.
Claims (9)
1. The utility model provides a blast furnace gas recovery system, includes coal gas recovery main line and damping down coal gas recovery branch road, in coal gas recovery main line is equipped with coarse dust remover and first sack cleaner in proper order, its characterized in that: the device is characterized in that a damping down gas recovery valve, a branch dust removing mechanism and an ejector are sequentially arranged on the damping down gas recovery branch, the ejector is connected with a working fluid pipe, a pressure relief opening of the first bag-type dust remover is connected with a first pressure relief pipe, the first pressure relief pipe is provided with a pressure relief valve, and the first pressure relief pipe is connected with the damping down gas recovery branch and a side joint is located at the upstream of the ejector.
2. The blast furnace gas recovery system of claim 1, wherein: the bypass point of the first pressure relief pipe is located at the upstream of the branch dust removing mechanism, and the first pressure relief pipe is connected to the high-pressure side of the first bag-type dust remover.
3. The blast furnace gas recovery system of claim 1, wherein: the bypass point of the first pressure relief pipe is positioned between the branch dust removing mechanism and the ejector, and the first pressure relief pipe is connected to the low pressure side of the first bag-type dust remover.
4. The blast furnace gas recovery system of claim 1, wherein: the inlet end of the damping down gas recovery branch is connected to the gas recovery main pipeline in a bypass mode, and the bypass point is located between the coarse dust remover and the first bag-type dust remover.
5. The blast furnace gas recovery system according to claim 4, wherein: the branch dust removing mechanism comprises a second cloth bag dust remover.
6. The blast furnace gas recovery system according to claim 5, wherein: the pressure relief opening of the second bag-type dust collector is connected with a second pressure relief pipe, a second pressure relief valve is arranged on the second pressure relief pipe, the second pressure relief pipe is connected to the damping down coal gas recovery branch and the bypass point is located between the branch dust removing mechanism and the ejector.
7. The blast furnace gas recovery system of claim 1, wherein: and a pressure reducing valve is further arranged on the damping down gas recovery branch and is positioned at the downstream of the ejector.
8. The blast furnace gas recovery system of claim 1, wherein: the main gas recovery pipeline comprises a gas ascending pipe, a gas descending pipe and a gas treatment pipe which are connected in sequence, wherein the gas ascending pipe is connected with a blast furnace, and the coarse dust remover and the first cloth bag dust remover are respectively arranged on the gas treatment pipe.
9. The blast furnace gas recovery system of claim 1, wherein: the coarse dust remover is a cyclone dust remover.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320983418.3U CN220393775U (en) | 2023-04-27 | 2023-04-27 | Blast furnace gas recovery system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320983418.3U CN220393775U (en) | 2023-04-27 | 2023-04-27 | Blast furnace gas recovery system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220393775U true CN220393775U (en) | 2024-01-26 |
Family
ID=89603159
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202320983418.3U Active CN220393775U (en) | 2023-04-27 | 2023-04-27 | Blast furnace gas recovery system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220393775U (en) |
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2023
- 2023-04-27 CN CN202320983418.3U patent/CN220393775U/en active Active
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