Electric arc furnace door oxygen lance particle blowing dephosphorization device

Abstract

The utility model belongs to the technical field of ferrous metallurgy steelmaking, and discloses an electric arc furnace door oxygen lance particle blowing dephosphorization device which is characterized in that a powder spraying sublance is arranged on a furnace door oxygen lance in parallel, and the furnace door oxygen lance is flush with the outlet end of the powder spraying sublance; pressurizing the powder spraying tank by using a pressurizing air source, keeping positive pressure in the tank, and ensuring smooth discharging of lime powder; lime powder in the powder spraying tank enters the powder spraying sublance through the spraying pipeline and enters the electric furnace body together with oxygen for spraying dephosphorization, and by means of the device, the reaction area between a solvent and molten steel can be enlarged, the interface reaction can be enhanced, the basicity of slag can be rapidly adjusted, and the dephosphorization reaction can be rapidly carried out.

Description

Technical Field

[0001] This utility model belongs to the field of steelmaking technology in iron and steel metallurgy, and particularly relates to a particle blowing dephosphorization device for oxygen lance at the furnace door of an electric arc furnace. Background Technology

[0002] Modern electric arc furnace (EAF) smelting technology has developed around the core goal of shortening the time required for green, efficient, and low-consumption production in EAFs. Currently, the primary method in EAF steelmaking is the use of basic electric arc furnaces. The addition of lime promotes slag formation within the furnace. The layer of oxides and silicates formed on the slag surface primarily protects the molten steel from oxidation. Furthermore, the addition of lime increases the basicity and melting point of the slag, making it easier to form and stabilize, thus protecting the molten steel from contamination. Lime also regulates the balance of chemical reactions within the furnace, improving the quality of the molten steel. Specifically, lime reacts with oxides in the slag to form relatively stable calcium silicate. This promotes oxidation reactions within the furnace, reduces impurities and oxide content, and improves the quality of the molten steel.

[0003] Currently, electric arc furnace steelmaking processes commonly use high-level silos to add "lump materials" and "batch materials" to the molten steel pool. The disadvantages of using "lump materials" are a longer melting time, lower reaction efficiency, and lower material utilization rate. To a certain extent, this can no longer meet the actual needs of the metallurgical industry for green, efficient, and low-consumption production. Due to the size of the lumps, the reaction interface is somewhat limited when "lump materials" and "batch materials" are added to the molten steel pool, which to some extent affects the rapid progress of various reactions during the smelting process. Another disadvantage of adding batch materials is that once a pile of material forms in the furnace and covers the slag, it may cause the oxygen lance jet to backflush and leak water if it approaches the oxygen lance, posing a certain safety hazard. Utility Model Content

[0004] To address the aforementioned problems, this invention provides a particulate dephosphorization device for oxygen lance at the furnace door of an electric arc furnace. This device can effectively expand the reaction interface between slag and lime during steelmaking and smelting, rapidly increase the basicity of the slag, facilitate the rapid dephosphorization reaction, and effectively reduce lime consumption.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a particle blowing dephosphorization device for oxygen lance at the furnace door of an electric arc furnace, including an electric furnace body, a furnace door oxygen lance, a powder injection auxiliary lance, a powder injection tank and a pressurized gas source.

[0006] The oxygen lance at the furnace door is installed on the electric furnace body. A powder injection auxiliary lance is arranged parallel to the oxygen lance at the furnace door. The outlet ends of the oxygen lance at the furnace door and the powder injection auxiliary lance are flush. Setting the outlet ends of the oxygen lance at the furnace door and the powder injection auxiliary lance together facilitates installation and ensures that the material is within the jet range of the oxygen lance after being sprayed out, thereby accelerating the reaction efficiency.

[0007] The pressurized air source is connected to the powder spraying tank through a pressurized pipeline. The powder spraying tank is used to hold lime powder. A pressurized valve is installed on the pressurized pipeline.

[0008] The powder spraying tank is equipped with a feed valve at the inlet and a lime powder control valve at the outlet. The powder spraying auxiliary gun is connected to the lime powder control valve through a spraying pipe.

[0009] The jetting pipe is equipped with a gas source control valve.

[0010] In a preferred embodiment of this invention, a feeding hopper connected to a feed valve is provided above the powder spraying tank, thereby facilitating the addition of lime powder into the powder spraying tank.

[0011] In a preferred embodiment of this invention, a grate is provided at the inlet of the feeding hopper to filter out large particles in the lime powder and prevent clogging of the spray pipe.

[0012] Preferably, the gaps in the grate are less than 5mm to prevent lime particles larger than 5mm from clogging the pipeline during the spraying process.

[0013] Preferably, the powder spraying tank is equipped with a stirring device to ensure uniform powder feeding during spraying.

[0014] In a preferred embodiment of this invention, the blowing pipe is connected to a pressurized gas source via a purging pipe. A purging control valve is provided on the purging pipe to prevent lime powder from clogging the powder spraying gun when blowing stops. When the powder spraying gun is clogged by lime powder, the purging control valve is opened to inject pressurized gas into the blowing pipe to purge the powder spraying gun.

[0015] Preferably, the powder spraying tank is equipped with a pressure relief valve to prevent excessive pressure inside the powder spraying tank from being caused by blockage of the spraying pipeline, which could lead to danger.

[0016] Preferably, the pressurized air source of this utility model is nitrogen gas with a pressure greater than 0.6 MPa, to prevent lime particles from absorbing moisture and pulverizing. High air moisture content can cause lime powder to clump together, affecting normal material feeding.

[0017] In a preferred embodiment of this invention, the water-cooling pipes of the oxygen lance at the furnace door and the water-cooling pipes of the powder injection auxiliary lance are connected, thus sharing a common water-cooling system.

[0018] In a preferred embodiment of this invention, the oxygen lance of the furnace door is hinged to the furnace body of the electric furnace and is used to adjust the position and angle of the spray, thereby spraying lime powder more evenly onto the surface of the molten steel.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model sets up a powder injection auxiliary lance parallel to the oxygen lance at the furnace door, and sets the outlet ends of the oxygen lance at the furnace door and the powder injection auxiliary lance flush; pressurizing the powder injection tank with a pressurized air source to maintain positive pressure inside the tank and ensure smooth feeding of lime powder; the lime powder in the powder injection tank enters the powder injection auxiliary lance through the injection pipe and enters the electric furnace body together with oxygen for injection dephosphorization. Through the above device, the reaction area between the solvent and the molten steel can be expanded, the interfacial reaction can be strengthened, the slag basicity can be quickly adjusted, and the dephosphorization reaction can be promoted rapidly. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the electric arc furnace door oxygen lance microparticle blowing dephosphorization device of this utility model;

[0021] In the diagram, 1 is the electric furnace body, 2 is the furnace door oxygen lance, 3 is the powder injection auxiliary lance, 4 is the powder injection tank, and 41 is the charging bin;

[0022] 5. Pressurized pipeline, 6. Pressurized valve, 7. Feed valve, 8. Lime powder control valve, 9. Pulse jetting pipeline, 10. Purge pipeline, 11. Purge control valve, 12. Pressure relief valve. Detailed Implementation

[0023] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0024] like Figure 1 As shown, an electric arc furnace door oxygen lance particulate dephosphorization device includes an electric furnace body 1, a furnace door oxygen lance 2, a powder injection auxiliary lance 3, a powder injection tank 4, and a pressurized gas source.

[0025] The oxygen lance 2 at the furnace door is mounted on the electric furnace body 1. A powder injection auxiliary lance 3 is arranged parallel to the oxygen lance 2 at the furnace door, and the powder injection auxiliary lance 3 is fixedly mounted on the oxygen lance 2 at the furnace door. The outlet ends of the oxygen lance 2 and the powder injection auxiliary lance 3 are flush. The oxygen lance 2 at the furnace door is hinged to the electric furnace body 1 and is connected to the oxygen supply system.

[0026] The pressurized air source is connected to the powder spraying tank 4 through the pressurized pipe 5. The powder spraying tank 4 is used to hold lime powder. The pressurized pipe 5 is equipped with a pressurized valve 6.

[0027] The powder spraying tank 4 is equipped with a feed valve 7 at the inlet and a lime powder control valve 8 at the outlet. The powder spraying auxiliary gun 3 is connected to the lime powder control valve 8 through a spraying pipe 9. The spraying pipe 9 is a flexible hose, which facilitates the adjustment of the spraying angle between the furnace door oxygen lance 2 and the powder spraying auxiliary gun 3.

[0028] Above the powder spraying tank 4 is a feeding hopper 41 connected to the feeding valve 7. Specifically, the feeding valve 7 is a butterfly valve.

[0029] A grate is provided at the inlet of the feeding bin 41.

[0030] The gaps in the grate are less than 5 mm.

[0031] The powder spraying tank 4 is equipped with a stirring device. Specifically, a stirring paddle is installed inside the powder spraying tank 4, and the drive shaft of the stirring paddle passes through the tank wall of the powder spraying tank 4 and is connected to a drive motor. The drive shaft is dynamically sealed to the tank wall of the powder spraying tank 4.

[0032] To ensure safety, the powder spraying tank 4 is equipped with a pressure relief valve 12.

[0033] In this embodiment, the jet pipe 9 is also connected to a pressurized air source through a purge pipe 10, and a purge control valve 11 is provided on the purge pipe 10.

[0034] The pressurized gas source is nitrogen gas with a pressure greater than 0.6 MPa.

[0035] In this embodiment, the water-cooling pipes of the oxygen lance 2 at the furnace door and the water-cooling pipes of the powder injection auxiliary lance 3 are connected, thereby enabling them to share the same cooling system.

[0036] In this invention, the high-speed jet of the oxygen lance microparticle blowing dephosphorization device at the furnace door of the electric arc furnace provides certain kinetic conditions for the reaction inside the furnace, which is beneficial for rapid slag formation and dephosphorization in the early stage of smelting.

[0037] High-speed jets can overcome the surface tension between steel and slag, reduce the violent reaction of carbon and oxygen in the furnace, reduce the loss of molten steel in the early decarburization process when steel and slag are not separated, and improve the yield of steel materials.

[0038] This invention is suitable for multi-component furnace charge structures, not only for all-cold charge smelting, but also for situations where a high proportion of molten iron or pig iron is added, or for smelting low-phosphorus varieties. It effectively stabilizes and controls the final phosphorus content, shortens the smelting cycle, and improves production efficiency. It completely solves the problem of material piling up inside the lime furnace, eliminates water leakage from oxygen lance jet backflushing, and achieves inherently safe production.

Claims

1. A microparticle-injected dephosphorization device for oxygen lance at the furnace door of an electric arc furnace, characterized in that: It includes the electric furnace body (1), furnace door oxygen lance (2), powder injection auxiliary lance (3), powder injection tank (4) and pressurized gas source; The oxygen lance (2) at the furnace door is installed on the furnace body (1) of the electric furnace. A powder injection auxiliary lance (3) is arranged parallel to the oxygen lance (2) at the furnace door. The outlet ends of the oxygen lance (2) at the furnace door and the powder injection auxiliary lance (3) are flush. The pressurized gas source is connected to the powder spraying tank (4) through a pressurized pipe (5). The powder spraying tank (4) is used to hold lime powder. A pressurized valve (6) is installed on the pressurized pipe (5). The powder spraying tank (4) is equipped with a feed valve (7) at the inlet and a lime powder control valve (8) at the outlet. The powder spraying auxiliary gun (3) is connected to the lime powder control valve (8) through a spraying pipe (9).

2. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: Above the powder spraying tank (4) is a feeding hopper (41) connected to the feed valve (7).

3. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 2, characterized in that: A grate is provided at the entrance of the feeding bin (41).

4. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 3, characterized in that: The gaps in the grate are less than 5 mm.

5. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: The powder spraying tank (4) is equipped with a stirring device.

6. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: The jet pipe (9) is connected to a pressurized air source through a purge pipe (10), and a purge control valve (11) is provided on the purge pipe (10).

7. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: The powder spraying tank (4) is equipped with a pressure relief valve (12).

8. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: The pressurized gas source is nitrogen gas with a pressure greater than 0.6 MPa.

9. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: The water cooling pipes of the oxygen lance (2) at the furnace door and the water cooling pipes of the powder injection auxiliary lance (3) are connected.

10. The electric arc furnace door oxygen lance microparticle blowing dephosphorization device according to claim 1, characterized in that: The oxygen lance (2) of the furnace door is hinged to the furnace body (1).

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