System and method for introducing steam into blast furnace

Abstract

The invention relates to the technical field of blast furnace ironmaking in ferrous metallurgy, in particular to a system and method for introducing steam into a blast furnace. One end of a steam header pipe is connected with the output end of a steam cylinder, one end of a steam branch pipe I is connected with a compressed air pipeline, and one end of a steam branch pipe II is communicated with the top of the blast furnace; the other end of the main steam pipe is connected with a second steam diffusion branch pipe, the other end of the first steam branch pipe is connected with the main steam pipe, the other end of the second steam branch pipe is connected with the second steam diffusion branch pipe, and the first steam diffusion branch pipe is connected with the main steam pipe. The device has the advantages that the steam header pipe, the steam branch pipe I, the steam branch pipe II, the steam diffusion branch pipe I and the steam diffusion branch pipe II are all subjected to heat preservation by adopting slag cotton, so that the pipelines are prevented from being frozen and blocked and heat loss is prevented; the steam header pipe, the first steam branch pipe, the second steam branch pipe, the first steam diffusion branch pipe and the second steam diffusion branch pipe are provided with electric valves used for physical isolation, use of steam in the blast furnace is ensured, and safety accidents of gas backflow and pipeline freezing and clamping are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of blast furnace ironmaking in steel metallurgy, and in particular to a system and method for introducing steam into a blast furnace. Background Art

[0002] In the blast furnace smelting process, steam is an important energy medium. The steam network is directly connected to the blast furnace through the steam pipe. When the steam pressure of the steam network is lower than the steam pressure in the blast furnace, there is a possibility that the coal gas in the blast furnace will flow back into the steam network along the steam pipe. When the steam pipe is not flowing, there is a possibility of freezing and jamming at the bends and weak insulation points of the steam pipe. In order to ensure production safety, the existing steam pipes are rectified. Summary of the invention

[0003] The purpose of the present invention is to provide a system and method for introducing steam into a blast furnace, so as to ensure the use of steam in the blast furnace and improve the safety measures.

[0004] To achieve the above object, the present invention is implemented through the following technical solutions:

[0005] A system for introducing steam into a blast furnace comprises a steam main pipe, a steam branch pipe 1, a steam branch pipe 2, a steam release branch pipe 1 and a steam release branch pipe 2, wherein one end of the steam main pipe is connected to the output end of a steam cylinder, one end of the steam branch pipe 1 is connected to a compressed air pipeline, one end of the steam branch pipe 2 is connected to a blast furnace top, the other end of the steam main pipe is connected to the steam release branch pipe 2, the other end of the steam branch pipe 1 is connected to the steam main pipe, the other end of the steam branch pipe 2 is connected to the steam release branch pipe 2, and the steam release branch pipe 1 is connected to the steam main pipe.

[0006] The steam main pipe is provided with valve three and valve four in sequence, and the connection points of valve three and valve four are connected with the other end of steam branch pipe one and steam release branch pipe one respectively.

[0007] A valve is provided on the steam branch pipe.

[0008] Valve six is ​​provided on steam branch pipe two.

[0009] A valve 2 is arranged on the steam discharging branch pipe 1, a gas sensor is arranged at the output end of the valve 2, and the gas sensor is connected with the sound and light alarm.

[0010] A valve five is provided on the steam release branch pipe two.

[0011] The input end of the steam cylinder is connected to the steam network, the steam network is used to provide a steam source to the steam cylinder, and the compressed air pipeline is used to provide a steam purge air source.

[0012] The method of introducing steam into the blast furnace is implemented based on PLC / DCS, which specifically includes:

[0013] S1. The steam pressure in the steam cylinder is controlled above 0.45 MPa, and the pressure in the blast furnace is controlled below 0.35 MPa;

[0014] S2. During normal production, the steam in the steam cylinder is not used, valves 1, 3, 4, 5 and 6 are closed, and valve 2 is opened to release the steam;

[0015] S3. During abnormal production, steam needs to be introduced into the blast furnace. Valve 2 is closed, and valves 3, 4, and 6 are opened in sequence to allow steam to flow directly into the blast furnace for operation.

[0016] S4. After the operation is completed, close valve 6 and valve 3 in sequence, open valve 5 and valve 1 in sequence, and use compressed air for purging. The purging time lasts for 3 to 5 minutes, and the compressed air pressure is controlled at 0.3 to 0.5 MPa.

[0017] S5. After the purge is completed, close valve 1, valve 4, and valve 5 in sequence, and open valve 2 to release;

[0018] S6. The gas sensor detects a gas leak and the sound and light alarm goes off.

[0019] Abnormal production includes blast furnace shutdown and blast furnace top temperature higher than the set temperature, which is judged to meet abnormal production. Otherwise, it is judged to be normal production.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. A steam cylinder is installed in front of the blast furnace. The diameter of the steam cylinder is twice the diameter of the steam main pipe. It is used for steam buffering to prevent the steam fluctuation in the blast furnace caused by the steam fluctuation of the steam pipe network;

[0022] 2. Electric valves are installed on the steam main pipe, steam branch pipe 1, steam branch pipe 2, steam release branch pipe 1, and steam release branch pipe 2. During abnormal production, operators can operate the electric valves on the upper computer to reduce the labor intensity and safety risks of operators;

[0023] 3. The steam main pipe, steam branch pipe 1, steam branch pipe 2, steam vent branch pipe 1, and steam vent branch pipe 2 are all insulated with slag wool to prevent pipe freezing and heat loss;

[0024] 4. The steam main pipe, steam branch pipe 1, steam branch pipe 2, steam vent branch pipe 1 and steam vent branch pipe 2 are equipped with electric valves for physical isolation to ensure the use of steam in the blast furnace and avoid safety accidents such as gas backflow and pipeline freezing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is the front view of the present invention.

[0026] In the figure: 1-electric valve one 2-electric valve two 3-electric valve three 4-electric valve four 5-electric valve five 6-electric valve six 7-steam branch pipe one 8-steam release branch pipe one 9-steam branch pipe two 10-steam release branch pipe two 11-steam main pipe. DETAILED DESCRIPTION

[0027] The present invention is described in detail below in conjunction with the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0028] The following examples are implemented on the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following examples. The methods used in the following examples are conventional methods unless otherwise specified.

[0029] Example 1

[0030] A steam cylinder is installed in front of the blast furnace for steam buffering. The diameter of the steam cylinder is 426mm, the diameter of the steam main is 219, and the diameters of the steam branch pipe 17, steam branch pipe 29, steam release branch pipe 18, and steam release branch pipe 210 are 80mm. The input end of the steam cylinder is connected to the steam pipe network, which is used to provide steam source to the steam cylinder. An electric valve is installed on the pipe at the output end of the steam cylinder. The pipe is directly laid to the top of the blast furnace and connected to the blast furnace. The pipe is equipped with slag wool insulation to prevent the pipe from freezing and heat loss. Figure 1 A steam system for introducing steam into a blast furnace comprises a steam main pipe, a steam branch pipe 1 7, a steam branch pipe 2 9, a steam release branch pipe 1 8, and a steam release branch pipe 2 10. One end of the steam main pipe is connected to an output end 1 of a steam cylinder, and an output end 2 of the steam cylinder is connected to other users. The other users are sealing valves on the furnace top. The sealing valves on the furnace top are used for heating and drying the internal valve plate to avoid the valve plate from getting stuck. An electric valve 3 3 and an electric valve 4 4 ​​are arranged on the steam main pipe in sequence. The connection points of the electric valve 3 3 and the electric valve 4 4 ​​are respectively connected to the other end of the steam branch pipe 1 7 and the steam release branch pipe 1 8. The steam branch pipe 1 7 is provided with an electric valve. The electric valve 1 is movable and the input end of the electric valve 1 is connected to the compressed air pipeline, which is used to provide a steam purge gas source. The steam release branch pipe 8 is provided with an electric valve 2, which is used for release. The output end of the electric valve 2 is provided with a gas sensor, which is connected to the sound and light alarm. One end of the steam branch pipe 29 is connected to the top of the blast furnace, and the other end of the steam branch pipe 29 and the other end of the steam main are respectively connected to the steam release branch pipe 210. The steam branch pipe 29 is provided with an electric valve 6, and the steam release branch pipe 210 is provided with an electric valve 5, which is used for release.

[0031] The method of introducing steam into the blast furnace is implemented based on PLC / DCS, which specifically includes:

[0032] S1. The steam pressure in the steam cylinder is controlled above 0.45 MPa, and the pressure in the blast furnace is controlled below 0.35 MPa;

[0033] S2. During normal production, the steam in the steam cylinder is not used, electric valve 1, electric valve 3, electric valve 4, electric valve 5, and electric valve 6 are closed, and electric valve 2 is opened to release the steam. Once a valve is not closed tightly, the gas sensor detects a gas leak, and the sound and light alarm goes off, prompting the operator to handle it in time.

[0034] S3, in the abnormal production state, steam needs to be introduced into the blast furnace, the electric valve 2 is closed, and the electric valve 3, the electric valve 4, and the electric valve 6 are opened in sequence, so that the steam can be directly passed to the blast furnace for operation;

[0035] S4. After the operation is completed (the completion of the operation is based on the gas content tested by the thermal workers, and the relevant personnel are notified by phone that the operation is completed), close the electric valve 6 and the electric valve 3 in sequence, open the electric valve 5 and the electric valve 1 in sequence, and use compressed air for purging. The purging time lasts for 4 minutes, and the compressed air pressure is controlled at 0.4 MPa;

[0036] S5. After the purge is completed, close the electric valve 1, the electric valve 4, and the electric valve 5 in sequence, and open the electric valve 2 to release;

[0037] The electric valve can be operated on the upper computer screen in the main control room. Each time the steam system is introduced into the blast furnace, compressed air blowing is required to prevent the steam condensate from accumulating and freezing, and to prevent gas residue in the pipeline.

[0038] The present invention provides a steam cylinder in front of the blast furnace, the diameter of the steam cylinder is twice the diameter of the steam main pipe, and the steam cylinder is used for steam buffering to prevent the steam fluctuation in the steam pipe network from causing the steam fluctuation in the blast furnace; the steam main pipe, the steam branch pipe 1, the steam branch pipe 2, the steam venting branch pipe 1, and the steam venting branch pipe 2 are installed with electric valves, when the production is abnormal, the operators can operate the electric valves on the upper computer to reduce the labor intensity and safety risks of the operators; the steam main pipe, the steam branch pipe 1, the steam branch pipe 2, the steam venting branch pipe 1, and the steam venting branch pipe 2 are all insulated with slag cotton to prevent the pipeline from freezing and heat loss; the steam main pipe, the steam branch pipe 1, the steam branch pipe 2, the steam venting branch pipe 1, and the steam venting branch pipe 2 are installed with electric valves for physical isolation to ensure the use of steam in the blast furnace and avoid the safety accidents of gas backflow and pipeline freezing.

Claims

1. A system for introducing steam into a blast furnace, characterized in that: It includes a steam main pipe, a steam branch pipe 1, a steam branch pipe 2, a steam release branch pipe 1, and a steam release branch pipe 2. One end of the steam main pipe is connected to the output end of the steam cylinder, one end of the steam branch pipe 1 is connected to the compressed air pipeline, one end of the steam branch pipe 2 is connected to the top of the blast furnace, the other end of the steam main pipe is connected to the steam release branch pipe 2, the other end of the steam branch pipe 1 is connected to the steam main pipe, the other end of the steam branch pipe 2 is connected to the steam release branch pipe 2, and the steam release branch pipe 1 is connected to the steam main pipe.

2. A blast furnace steam introduction system according to claim 1, characterized in that: The steam main pipe is provided with valve three and valve four in sequence, and the connection between valve three and valve four is connected with the other end of steam branch pipe one and steam release branch pipe one respectively.

3. The system for introducing steam into a blast furnace according to claim 1, characterized in that: The steam branch pipe one is provided with a valve one.

4. The system for introducing steam into a blast furnace according to claim 1, characterized in that: The steam branch pipe 2 is provided with a valve 6.

5. The system for introducing steam into a blast furnace according to claim 1, characterized in that: The steam discharging branch pipe 1 is provided with a valve 2, the output end of the valve 2 is provided with a gas sensor, and the gas sensor is connected with the sound and light alarm.

6. The system for introducing steam into a blast furnace according to claim 1, characterized in that: The steam discharging branch pipe 2 is provided with a valve 5.

7. The system for introducing steam into a blast furnace according to claim 1, characterized in that: The input end of the steam cylinder is connected to a steam pipe network, which is used to provide a steam source for the steam cylinder, and the compressed air pipeline is used to provide a steam purge air source.

8. The system according to any one of claims 1 to 7 implements a method for introducing steam into a blast furnace, which is implemented based on PLC / DCS, and is characterized in that: Specifically include: S1. The steam pressure in the steam cylinder is controlled above 0.45 MPa, and the pressure in the blast furnace is controlled below 0.35 MPa; S2. During normal production, the steam in the steam cylinder is not used, valves 1, 3, 4, 5 and 6 are closed, and valve 2 is opened to release the steam; S3. During abnormal production, steam needs to be introduced into the blast furnace. Valve 2 is closed, and valves 3, 4, and 6 are opened in sequence to allow steam to flow directly into the blast furnace for operation. S4. After the operation is completed, close valve 6 and valve 3 in sequence, open valve 5 and valve 1 in sequence, and use compressed air for purging. The purging time lasts for 3 to 5 minutes, and the compressed air pressure is controlled at 0.3 to 0.5 MPa. S5. After the purge is completed, close valve 1, valve 4, and valve 5 in sequence, and open valve 2 to release; S6. The gas sensor detects a gas leak and the sound and light alarm goes off.

9. The method for introducing steam into a blast furnace according to claim 8, characterized in that: The abnormal production includes blast furnace shutdown and blast furnace top temperature higher than the set temperature, which is judged to be abnormal production. Otherwise, it is judged to be normal production.

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