Electric furnace wall cluster oxygen combustion gun capable of improving penetration rate

Abstract

The utility model relates to the technical field of electric furnace smelting, in particular to an electric furnace wall cluster oxygen combustion lance capable of improving the penetration rate, which comprises an oxygen lance body, the oxygen lance body is of a multi-layer pipe structure composed of a central oxygen pipe, a middle gas pipe and an outer layer oxygen pipe, the central oxygen pipe is used for introducing oxygen, and the middle gas pipe is used for introducing oxygen; a circular seam between the central oxygen pipe and the middle gas pipe is used for introducing natural gas, a circular seam between the middle gas pipe and the outer-layer oxygen pipe is used for introducing oxygen, and one end of the oxygen lance body is provided with a Laval nozzle structure. The method has the effect of improving the oxygen supply efficiency and the penetration rate.

Description

Technical Field

[0001] This application relates to the technical field of electric furnace smelting, and in particular to a bundled oxygen lance for electric furnace walls that improves penetration. Background Technology

[0002] With the increasing demand in the steel market and stricter environmental protection requirements, electric arc furnace (EAF) smelting, as a highly efficient, clean, and energy-saving smelting method, is gaining increasing favor among steel companies. EAF smelting can significantly reduce environmental pollution and improve production efficiency and product quality. However, despite the relatively mature technology of EAF smelting, several challenges remain regarding the oxygen supply system, such as insufficient oxygen supply intensity, long smelting time, and high energy and alloy consumption. Therefore, improving the EAF oxygen supply system to enhance oxygen supply efficiency and penetration has become a key focus of current research. Utility Model Content

[0003] In order to improve oxygen supply efficiency and penetration rate, this application provides an electric furnace wall bundled oxygen combustion lance with improved penetration rate.

[0004] The electric furnace wall clustered oxygen lance for improving penetration rate provided in this application adopts the following technical solution:

[0005] A clustered oxygen-fuel lance for improving penetration rate in an electric furnace wall includes an oxygen lance body. The oxygen lance body is a multi-layered tube structure composed of a central oxygen tube, an intermediate gas tube, and an outer oxygen tube. The central oxygen tube is used to introduce oxygen, the annular gap between the central oxygen tube and the intermediate gas tube is used to introduce natural gas, and the annular gap between the intermediate gas tube and the outer oxygen tube is used to introduce oxygen. One end of the oxygen lance body has a Laval nozzle structure.

[0006] By adopting the above technical solution, the Laval nozzle structure can significantly improve the penetration depth and stirring intensity of the oxygen jet, allowing oxygen to enter the core region of the molten pool more effectively, accelerating the metal oxidation reaction and increasing the smelting rate. Simultaneously, it reduces energy and alloy consumption, lowers slag volume and pollutant emissions, and improves productivity and product quality. Furthermore, the Laval nozzle design allows the oxygen jet to maintain a high axial velocity over a longer distance, enhancing the working efficiency and service life of the oxygen lance.

[0007] Optionally, the oxygen lance body has a first oxygen inlet, a gas inlet, and a second oxygen inlet. The first oxygen inlet passes through the outer oxygen tube and the intermediate gas tube and is connected to the end of the central oxygen tube away from the Laval nozzle structure. The gas inlet passes through the outer oxygen tube and is connected to the end of the intermediate gas tube away from the Laval nozzle structure. The second oxygen inlet is connected to the end of the outer oxygen tube away from the Laval nozzle structure.

[0008] By adopting the above technical solution, the design of the first oxygen inlet, the gas inlet, and the second oxygen inlet of the oxygen lance body allows oxygen and natural gas to enter the central oxygen tube, the intermediate gas tube, and the outer oxygen tube respectively, achieving precise control and mixing of oxygen and natural gas. This structural design not only improves the speed and stability of the oxygen jet but also enhances the penetration and stirring intensity of the concentrated oxygen flow, effectively promoting metal oxidation and temperature rise, reducing slag volume and pollutant emissions, and improving productivity and product quality.

[0009] Optionally, the Laval nozzle structure has a contraction section, a stabilization section, and an expansion section arranged sequentially from the first oxygen inlet side. The diameter of the contraction section gradually decreases, and the diameter of the expansion section gradually increases. The contraction section accounts for 20% to 35% of the total length of the Laval nozzle structure, the stabilization section accounts for 5% to 10% of the total length of the Laval nozzle structure, and the expansion section accounts for 55% to 75% of the total length of the Laval nozzle structure. The design Mach number of the Laval nozzle structure is 2-2.4.

[0010] By adopting the above technical solution, the optimized ratio of the contraction, stabilization, and expansion sections enables oxygen to maintain a high flow rate and concentration over a longer distance, thereby enhancing the impact force and penetration depth on the molten pool. This improvement not only increases smelting efficiency but also reduces localized overheating caused by uneven oxygen diffusion, helping to maintain a balanced energy distribution in the arc region. Furthermore, a stable oxygen jet also helps improve the mixing uniformity between reactants, accelerates the metal oxidation process, and further enhances smelting quality.

[0011] Optionally, the flow rate of the central oxygen tube is in the range of 150–3300 Nm³. 3 / h, the flow rate of the intermediate gas pipe is 100~300Nm 3 / h, the flow rate range of the outer oxygen tube is 50~200Nm 3 / h.

[0012] By adopting the above technical solution, the central oxygen tube, intermediate gas tube, and outer oxygen tube of the furnace wall cluster oxygen lance are set within a specific flow range, which can accurately control the flow rate of each gas. The reasonable flow distribution helps to reduce energy consumption, reduce alloy consumption, improve resource utilization, and further optimize the overall performance of electric furnace smelting.

[0013] Optionally, the Laval nozzle structure is fitted with a cooling copper ring, the inner wall of the cooling copper ring is fitted with the Laval nozzle structure, the cooling copper ring has an annular cooling water channel, one side of the outer wall of the cooling copper ring is provided with a cooling water inlet connected to the annular cooling water channel, and the other side is provided with a cooling water outlet connected to the annular cooling water channel.

[0014] By adopting the above technical solutions, the cooling copper ring can effectively reduce thermal damage to the Laval nozzle structure under high-temperature environments, extending the service life of the oxygen lance. Simultaneously, the design of the cooling water channel allows cooling water to circulate within the cooling copper ring, further improving the cooling effect and ensuring the oxygen lance maintains good working condition during long-term operation. Furthermore, the tight fit between the cooling copper ring and the Laval nozzle structure enhances the overall mechanical strength and stability of the oxygen lance, preventing deformation and damage caused by high temperatures.

[0015] Optionally, the number of the annular cooling water channels can be multiple.

[0016] By adopting the above technical solution, the increased number of annular cooling water channels effectively improves cooling efficiency, ensuring stable operation of the oxygen lance for extended periods in high-temperature environments and extending its service life. Simultaneously, the design of multiple annular cooling water channels facilitates uniform heat dissipation, preventing localized overheating and further enhancing the safety and reliability of the equipment.

[0017] Optionally, the oxygen lance body is provided with a connecting flange for connection to an electric arc furnace.

[0018] By adopting the above technical solution, the connecting flange allows the oxygen lance to be conveniently and reliably fixed on the electric arc furnace, ensuring its stable operation under high temperature and high pressure conditions. Furthermore, the design of the connecting flange facilitates the disassembly and maintenance of the oxygen lance, improving the operability and safety of the equipment.

[0019] In summary, this application includes at least one of the following beneficial technical effects:

[0020] 1. The furnace wall clustered oxygen lance with Laval nozzle structure can make the oxygen jet reach Mach 2.2, forming a clustered oxygen flow similar to a laser beam, which significantly improves the oxygen lance penetration rate and oxygen supply efficiency, and solves the problems of low penetration rate and uneven oxygen supply of traditional oxygen lances.

[0021] 2. The concentrated oxygen flow can penetrate deep into the center of the molten iron, accelerating the oxidation and removal of impurities such as carbon, silicon, and manganese, reducing slag volume and alloy consumption, and improving product quality and purity;

[0022] 3. By optimizing the design parameters and installation position of the oxygen lance, the temperature and pressure within the arc area were increased, enhancing the stability and strength of the arc, reducing energy consumption and electrode wear, and improving overall smelting efficiency. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the electric furnace wall clustered oxygen combustion lance for improving penetration rate provided in the embodiments of this application.

[0024] Figure 2This is a schematic diagram of the internal structure of the electric furnace wall clustered oxygen combustion lance for improving penetration provided in the embodiments of this application.

[0025] Explanation of reference numerals in the attached drawings: 1-Oxygen lance body; 101-Central oxygen pipe; 102-Intermediate gas pipe; 103-Outer oxygen pipe; 104-First oxygen inlet; 105-Gas inlet; 106-Second oxygen inlet; 107-Laval nozzle structure; 2-Cooling copper ring; 201-Annular cooling water channel; 202-Cooling water inlet; 203-Cooling water outlet; 3-Connecting flange. Detailed Implementation

[0026] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.

[0027] This application discloses a clustered oxygen combustion lance for improving the penetration rate of an electric furnace wall.

[0028] like Figure 1 and Figure 2 As shown, the electric furnace wall-mounted oxygen-fuel lance for improving penetration includes an oxygen lance body 1. The oxygen lance body 1 is a multi-layered tube structure composed of a central oxygen tube 101, an intermediate gas tube 102, and an outer oxygen tube 103. Its material can be T2 copper with a thickness of ten millimeters. In specific implementations, the central oxygen tube 101 can be machined by a CNC lathe using a forged copper head to reduce the adverse effects on the oxygen jet caused by insufficient machining precision. The central oxygen tube 101 is used to introduce oxygen, the annular gap between the central oxygen tube 101 and the intermediate gas tube 102 is used to introduce natural gas, and the annular gap between the intermediate gas tube 102 and the outer oxygen tube 103 is used to introduce oxygen. One end of the oxygen lance body 1 has a Laval nozzle structure 107.

[0029] The Laval nozzle structure 107 significantly improves the penetration depth and stirring intensity of the oxygen jet, allowing oxygen to enter the core region of the molten pool more effectively, accelerating the metal oxidation reaction and increasing the smelting rate. Simultaneously, it reduces energy and alloy consumption, lowers slag volume and pollutant emissions, and improves productivity and product quality. Furthermore, the design of the Laval nozzle structure 107 enables the oxygen jet to maintain a high axial velocity over a longer distance, enhancing the working efficiency and service life of the oxygen lance.

[0030] like Figure 1 and Figure 2As shown, the oxygen lance body 1 has a first oxygen inlet 104, a gas inlet 105, and a second oxygen inlet 106. The first oxygen inlet 104 penetrates the outer oxygen pipe 103 and the intermediate gas pipe 102 and is connected to the end of the central oxygen pipe 101 away from the Laval nozzle structure 107. The gas inlet 105 penetrates the outer oxygen pipe 103 and is connected to the end of the intermediate gas pipe 102 away from the Laval nozzle structure 107. The second oxygen inlet 106 is connected to the end of the outer oxygen pipe 103 away from the Laval nozzle structure 107. The design of the first oxygen inlet 104, gas inlet 105, and second oxygen inlet 106 of the oxygen lance body 1 allows oxygen and natural gas to enter the central oxygen pipe 101, the intermediate gas pipe 102, and the outer oxygen pipe 103 respectively, achieving precise control and mixing of oxygen and natural gas. This structural design not only improves the velocity and stability of the oxygen jet but also enhances the penetration and stirring intensity of the concentrated oxygen flow, effectively promoting metal oxidation and temperature rise, reducing slag volume and pollutant emissions, and improving productivity and product quality.

[0031] To prevent accidents caused by backfire of oxygen and natural gas, backfire prevention devices can be installed at the first oxygen inlet 104, the gas inlet 105, and the second oxygen inlet 106. These backfire prevention devices can be made of stainless steel and have an internal one-way valve that allows gas to pass only when the gas flow is in the correct direction and automatically closes when the flow is reversed, thus avoiding the risk of fire and explosion.

[0032] like Figure 1 and Figure 2 As shown, the Laval nozzle structure 107 comprises three main sections extending from the first oxygen inlet 104: a contraction section, a stabilization section, and a diffusing section. The diameter of the contraction section gradually decreases, while the diameter of the diffusing section gradually increases. The contraction section occupies 20% to 35% of the total length of the Laval nozzle, the stabilization section occupies 5% to 10%, and the diffusing section occupies 55% to 75%. The design Mach number of the Laval nozzle structure 107 is between 2 and 2.4. By optimizing the ratio of the contraction, stabilization, and diffusing sections, oxygen can maintain high-speed flow and high concentration over a greater distance, thereby enhancing the impact force and penetration depth on the molten pool. This structural improvement not only improves smelting efficiency but also reduces localized overheating caused by uneven oxygen distribution, helping to maintain a balanced energy distribution in the arc region. Furthermore, a stable oxygen jet also helps improve the mixing uniformity between reactants, accelerates the metal oxidation process, and further improves smelting quality.

[0033] Optionally, the flow rate range of the central oxygen pipe 101 is 150–3300 Nm³ / h, the flow rate range of the intermediate gas pipe 102 is 100–300 Nm³ / h, and the flow rate range of the outer oxygen pipe 103 is 50–200 Nm³ / h. The central oxygen pipe 101, intermediate gas pipe 102, and outer oxygen pipe 103 of the furnace wall-mounted oxygen-fuel lance are each set within a specific flow rate range, enabling precise control of the flow rate of each gas. Reasonable flow rate distribution helps reduce energy consumption, decrease alloy consumption, improve resource utilization, and further optimize the overall performance of electric furnace smelting.

[0034] To further improve the service life and safety of the clustered oxygen combustion gun, a cooling copper ring 2 is fitted around the outer casing of the Laval nozzle structure 107. The inner wall of the cooling copper ring 2 fits tightly with the Laval nozzle structure 107 to ensure good heat dissipation. Multiple annular cooling water channels 201 are provided inside the cooling copper ring 2, each channel connecting to an external cooling water inlet 202 and a cooling water outlet 203, ensuring smooth water circulation. The cooling water inlet 202 is located on one side of the outer wall of the cooling copper ring 2, and the cooling water outlet 203 is located on the other side. This effectively removes the heat generated during nozzle operation, preventing overheating damage.

[0035] In addition, the oxygen lance body 1 is fitted with a connecting flange 3 for connection to the electric arc furnace, facilitating installation and disassembly. The design of the connecting flange 3 must consider the requirements of high strength and high sealing performance to ensure long-term stable operation under high temperature and high pressure environments. The connecting flange 3 can be bolted to the electric arc furnace, making installation simple and quick, and facilitating daily maintenance and repair.

[0036] The implementation principle of the electric furnace wall-mounted clustered oxygen lance with improved penetration rate in this application embodiment is as follows: By adopting a multi-layer tube structure and Laval nozzle design, high-speed, high-pressure, and high-concentration oxygen injection is achieved, forming a powerful clustered oxygen flow. This design not only improves the penetration rate and oxygen supply efficiency of the oxygen lance but also extends its service life and reduces maintenance costs. Simultaneously, by optimizing the cooling system and connection method, stable operation of the oxygen lance under high-temperature and high-pressure environments is ensured, improving the overall performance and economic benefits of electric furnace smelting.

[0037] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A penetration enhancing oxy-fuel burner for furnace walls of an electric furnace, characterized in that The application relates to an oxygen lance body (1) which is a multi-layer tube structure composed of a central oxygen tube (101), an intermediate gas tube (102) and an outer oxygen tube (103), the central oxygen tube (101) is used for feeding oxygen, an annular gap between the central oxygen tube (101) and the intermediate gas tube (102) is used for feeding natural gas, an annular gap between the intermediate gas tube (102) and the outer oxygen tube (103) is used for feeding oxygen, and one end of the oxygen lance body (1) is provided with a Laval nozzle structure (107). The oxygen lance body (1) is provided with a first oxygen inlet (104), a gas inlet (105) and a second oxygen inlet (106), the first oxygen inlet (104) penetrates through the outer oxygen tube (103) and the intermediate gas tube (102) and is connected to one end of the central oxygen tube (101) away from the Laval nozzle structure (107), the gas inlet (105) penetrates through the outer oxygen tube (103) and is connected to one end of the intermediate gas tube (102) away from the Laval nozzle structure (107), and the second oxygen inlet (106) is connected to one end of the outer oxygen tube (103) away from the Laval nozzle structure (107).

2. The improved through-the-wall oxygen lances for electric furnaces as claimed in claim 1 wherein, The Laval nozzle structure (107) is provided with a converging section, a stable section and a diverging section from one side of the first oxygen inlet (104) in sequence, the caliber of the converging section gradually decreases, the caliber of the diverging section gradually increases, the converging section accounts for 20%-35% of the total length of the Laval nozzle structure (107), the stable section accounts for 5%-10% of the total length of the Laval nozzle structure (107), the diverging section accounts for 55%-75% of the total length of the Laval nozzle structure (107), and the design Mach number of the Laval nozzle structure (107) is 2-2.

4.

3. The improved through-the-wall oxygen lances for electric furnaces as claimed in claim 2 wherein, The flow range of the central oxygen tube (101) is 150-3300 Nm3 / h, the flow range of the intermediate gas tube (102) is 100-300 Nm3 / h, and the flow range of the outer oxygen tube (103) is 50-200 Nm3 / h.

4. The improved through-the-wall oxygen lances for electric furnaces of claim 3, characterized in that, The Laval nozzle structure (107) is provided with a cooling copper ring (2), the inner side wall of the cooling copper ring (2) is matched with the Laval nozzle structure (107), the cooling copper ring (2) is internally provided with an annular cooling water channel (201), one side of the outer wall of the cooling copper ring (2) is provided with a cooling water inlet (202) which is in communication with the annular cooling water channel (201), and the other side is provided with a cooling water outlet (203) which is in communication with the annular cooling water channel (201).

5. The improved through-the-wall oxygen lance for use in an electric furnace as claimed in claim 1, wherein The number of the annular cooling water channels (201) is multiple.

6. The improved through-the-wall oxygen lance for use in an electric furnace as claimed in claim 5 wherein, The oxygen lance body (1) is provided with a connecting flange (3) which is used for being connected with an electric arc furnace.

7. The improved OTEC boiler wall cluster oxyfuel gun of claim 1, wherein, ​

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