Method for reducing aluminum loss rate of aluminum-containing steel

Abstract

The invention relates to a method for reducing the aluminum loss rate of aluminum-containing steel, which mainly comprises the step of adjusting wire feeding in an LF refining furnace and specifically comprises the following steps: firstly, opening a side suction dust removal system, controlling the opening degree of a gate valve of the dust removal system to be 25-35%, closing a temperature measurement sampling hole, and stopping heating; the electrodes are powered off and lifted, three-phase electrode holes are sealed, and micro-vacuum pressure is formed; then the wire feeding hole is opened, and the wire feeding guide pipe descends to feed wires; and finally, withdrawing the wire, closing the wire feeding hole, and calculating the burn-out rate of the aluminum element. The gate valve is additionally arranged on the side suction dust removal system, the opening degree of the gate valve can be adjusted in time according to the smoke overflow condition of the electrode ring, smoke on the upper portion of the furnace cover electrode ring can be kept to overflow and be recovered, good sealing between the refining furnace cover and a steel ladle is achieved, the reducing atmosphere under the micro-positive pressure in the furnace is guaranteed, aluminum is prevented from being oxidized, and the service life of the refining furnace is prolonged. Meanwhile, when the three-phase electrode is powered off and leaves the station, the electrode cover is additionally arranged on the three-phase electrode hole, and the situation that molten steel is exposed in a large area and oxidized due to the fact that too much air is sucked in the wire feeding process is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of steelmaking, and in particular to a method for reducing the aluminum loss rate of aluminum-containing steel. Background Art

[0002] Aluminum-containing steel is an alloy material composed of aluminum, steel, and other elements. It has the advantages of high hardness, high strength, and good corrosion resistance. It can effectively resist corrosion and reduce the oxidation reaction rate, thereby extending the service life of the material. In addition, aluminum-containing steel also has excellent cutting, welding and extrudability, and can be precisely processed into various shapes. Therefore, it has been widely used in the aviation, automotive and other manufacturing industries. The traditional aluminum-containing steel production process includes KR desulfurization, LD converter, post-furnace argon blowing treatment, LF refining furnace and CC continuous casting machine. However, in the actual production process, the amount of aluminum and manganese added when the converter is discharged is too large, resulting in a high aluminum burn-out rate during the aluminum-containing steel smelting process. Multiple aluminum supplements are often required during the refining process. This not only affects the production stability of the steel, but may also cause molten steel pollution, thereby affecting the quality of the molten steel and making the castability of the continuous casting molten steel worse. Table 1 provides a statistical analysis of the aluminum burn-off rate in molten steel during various aluminum-containing steel smelting processes in a 210t furnace. As can be seen from Table 1, aluminum burn-off is particularly severe in the LF refining furnace, accounting for as much as 73.81%, making it the primary factor contributing to the high aluminum burn-off rate in molten steel. This is primarily due to excessive dust removal and exhaust capacity during the LF refining process, as well as poor wire feed sealing, which results in significant aluminum oxidation and increased aluminum consumption. Prior art researchers have attempted to reduce aluminum loss by using high-basicity refining slag systems during VD refining. For example, Chinese Patent Publication No. CN107058681B discloses a method for improving aluminum yield during VD refining. Furthermore, researchers have manipulated the combined mass fractions of FeO and MnO in the LF furnace final slag to reduce the oxygen content released into the VD furnace, thereby precisely controlling the amount of aluminum ingot added. For example, Chinese Patent Publication No. CN111321274B discloses a method for controlling aluminum in molten steel during refining. However, these methods are relatively complicated and involve vacuum refining, which places high demands on equipment and personnel operation.

[0003] Therefore, how to effectively reduce the aluminum burnout rate in aluminum-containing steel while simplifying the production process has become a technical problem that needs to be solved urgently. In order to solve the above problems, the existing technology needs to be improved urgently.

[0004] Table 1

[0005] factor Frequency Cumulative frequency Cumulative percentage LF refining furnace has high burnout rate 155 155 73.81 High converter burnout rate 20 175 83.33 The burning rate of the argon blowing station is high 15 190 90.48 Poor continuous casting protection 15 205 97.62 Other causes 5 210 100 total 210 210 100 Summary of the Invention

[0006] The purpose of this application is to provide a method for reducing the aluminum loss rate of aluminum-containing steel, which has the advantages of reducing the oxidation and burning loss of aluminum elements by optimizing the LF refining furnace feeding process, thereby improving production stability and molten steel quality.

[0007] This application provides a method for reducing the aluminum loss rate of aluminum-containing steel. The technical solution is as follows:

[0008] The process route includes KR stirring desulfurization - LD converter - post-furnace argon blowing treatment - LF refining furnace - CC continuous casting machine. The wire feeding steps in the LF refining furnace are as follows:

[0009] Step S1. Adjust the opening of the dust removal valve in the dust removal system and close the temperature sampling hole;

[0010] Step S2. Stop heating, turn off the motor power and raise or move the workstation;

[0011] Step S3. After transferring the workstation, close the three-phase electrode holes;

[0012] Step S4. Open the wire feeding hole and lower the wire feeding conduit;

[0013] Step S5. Select the wire feeding type and set the wire feeding speed;

[0014] Step S6: After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and the aluminum element burnout rate is calculated.

[0015] Furthermore, the present application also proposes that the opening of the dust removal plug valve in S1 is controlled at 25-35%.

[0016] Furthermore, the present application also proposes that the temperature of the molten steel in the refining furnace after stopping the heating in S2 is 1500-1600°C.

[0017] Furthermore, the present application also proposes that the three-phase electrode holes in S3 are sealed with electrode hole covers, and the material of the electrode hole covers is nickel-based alloy.

[0018] Furthermore, the present application also proposes that the depth of the wire feeding conduit in S4 is lowered to 0.6 to 0.75 of the depth of the molten steel, and the wire feeding conduit is perpendicular to the surface of the molten steel.

[0019] Furthermore, the present application also proposes that the type of wire to be fed in S5 is alloy wire, the diameter of the wire to be fed is 6 to 20 mm, the wire feeding speed is 1.8 to 2 m / min, and the wire feeding amount is 0.30 to 0.45 kg / t.

[0020] Furthermore, the present application also proposes that the alloy wire is a manganese alloy or an aluminum alloy.

[0021] Furthermore, the present application also proposes that the calculation formula for the aluminum element burnout rate in S6 is as follows:

[0022]

[0023] Among them, the initial value of aluminum content in molten steel is the aluminum content in molten steel after deoxidation and alloying in the converter; the end value of aluminum content in molten steel is the aluminum content in the billet of the continuous casting machine.

[0024] (1) The present application adds a gate valve to the side suction dust removal system, and the gate valve opening can be adjusted in time according to the overflow of the electrode ring smoke, so as to keep the smoke above the furnace cover electrode ring in a state where it can overflow and be recovered, thereby achieving a good seal between the refining furnace cover and the ladle, ensuring a reducing atmosphere under a slightly positive pressure in the furnace, avoiding the inhalation of a large amount of air, and preventing aluminum from being oxidized;

[0025] (2) When the three-phase electrode is powered off and leaves the workstation, the present application adds an electrode cover to the three-phase electrode hole to prevent the molten steel from being exposed to a large area during the wire feeding process and from being oxidized by inhaling too much air;

[0026] (3) The present application selects a feeding speed controlled within the range of 1.8 to 2 m / min, and the depth of the feeding tube is lowered to 0.6 to 0.75 of the height of the molten steel. When the molten steel is fed into the wire, it can fully contact the reaction and oxidation, avoiding excessive speed, insufficient oxidation, and excessive speed, which causes the molten steel to contact too much air and waste energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Flowchart of the LF refining furnace feeding steps for this application. DETAILED DESCRIPTION

[0028] The technical solutions of this application will be described clearly and completely below, in conjunction with the accompanying drawings. It should be understood that the described embodiments represent only a portion of the embodiments of this application, and not all of them. The components of this application, generally described and illustrated in the drawings herein, may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but rather merely represents selected embodiments of this application. All other embodiments derived by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. Furthermore, in the description of this application, the terms "first," "second," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] In the traditional aluminum-containing steel production process, aluminum burnout is a prominent issue during the LF refining furnace stage. This is primarily due to excessive dust removal system exhaust capacity and inadequate wire feed sealing, which leads to increased aluminum oxidation. During this process, the molten steel is exposed to a high-oxygen environment, where aluminum reacts with oxygen to form alumina, reducing aluminum yield and directly impacting the stability of the molten steel's composition and continuous casting performance.

[0030] For example, the background technology in this application mentioned that in the 210-ton furnace aluminum-containing steel smelting process, the dust removal plug valve of the LF refining furnace was not adjusted to a reasonable opening, the temperature sampling hole and the three-phase electrode hole were not completely closed, and the external air invaded the furnace through the unsealed holes. During the wire feeding process, the insertion depth and verticality of the catheter were not accurately controlled, and the fluctuation of the wire feeding speed caused uneven distribution of the aluminum wire, further aggravating the oxidation reaction. In this scenario, the burn-out rate of aluminum element in molten steel increased significantly, and aluminum needed to be frequently replenished to maintain the target composition, resulting in increased complexity of process control.

[0031] If these issues are not addressed, aluminum burnout will increase smelting costs, and frequent aluminum replenishment operations may introduce foreign inclusions, contaminating the cleanliness of the molten steel and reducing the internal quality of the continuous casting ingot. Furthermore, process fluctuations can lead to deviations in steel grade composition, affecting the mechanical properties and corrosion resistance of the final product, increasing scrap rates and making subsequent processing more difficult, thus limiting the reliability of aluminum-containing steel in high-end manufacturing applications.

[0032] When faced with the above problems, this application first focuses on the key link of aluminum element burnout in the LF refining furnace stage, and conducts an in-depth analysis of the linkage effect between the dust removal system and the wire feeding seal. In the traditional process, the full opening of the dust removal plug valve leads to excessive negative pressure in the furnace, which accelerates the infiltration of external air. At the same time, the unsealed temperature measuring holes and electrode holes in the wire feeding process form gas exchange channels, exacerbating aluminum oxidation. In response to this, this application proposes to balance the furnace pressure by dynamically adjusting the opening of the dust removal plug valve and blocking the external oxygen source input path. It was further discovered that the insertion method of the wire feeding conduit directly affects the degree of oxidation of the aluminum wire, and operational continuity must be achieved through workstation transfer and hole sealing to avoid secondary oxidation of molten steel. Finally, dust removal control, workstation adjustment, hole sealing and wire feeding parameter optimization are integrated to form a synergistic solution.

[0033] In this regard, the present application proposes a method for reducing the aluminum loss rate of aluminum-containing steel. The process route includes KR stirring desulfurization-LD converter-post-furnace argon blowing treatment-LF refining furnace-CC continuous casting machine. The wire feeding steps in the LF refining furnace are: adjust the opening of the dust removal plug valve in the dust removal system and close the temperature measurement sampling hole; stop heating, cut off the power to the motor and raise or transfer the workstation; close the three-phase electrode hole after transferring the workstation; open the wire feeding hole and lower the wire feeding guide tube; select the wire feeding type and set the wire feeding speed; after the wire feeding is completed, the wire feeding guide tube rises, closes the wire feeding hole, and calculates the aluminum element burn-out rate.

[0034] Controlling the dust removal valve opening at 25-35% means adjusting the size of the dust removal system's valve opening to control the gas flow rate, reducing the amount of oxygen entering the refining furnace and thereby reducing the likelihood of aluminum coming into contact with oxygen. Closing the temperature measurement and sampling holes means sealing the temperature measurement and sampling holes on the furnace during wire feeding to prevent air from entering the furnace through these holes and avoid oxidation reactions between aluminum and oxygen at high temperatures. Stopping heating and relocating the workstation means cutting off the power supply and raising or moving the electrodes before wire feeding to prevent localized oxidation caused by high electrode temperatures and to create space for wire feeding operations. Sealing the three-phase electrode holes with nickel-based alloy means using high-temperature-resistant and oxidation-resistant nickel-based alloy covers to seal the electrode holes, isolating them from air and preventing aluminum oxidation in high-temperature environments. Lowering the wire feeding conduit to 0.6-0.75 times the depth of the molten steel means inserting the wire feeding conduit into the molten steel at a specific depth, allowing the alloy wire to enter the molten steel directly and reducing the time the aluminum is exposed to the oxidizing atmosphere on the steel surface. The wire feeding speed is set at 1.8-2 m / min to control the rate at which the alloy wire enters the molten steel, ensuring uniform dissolution of the aluminum and reducing splashing or oxidation caused by excessive speed. The wire feeding rate is set at 0.30-0.45 kg / t to precisely control the amount of alloy wire added based on the weight of the molten steel, avoiding excessive wire feeding that could increase the aluminum burnout rate while ensuring the target aluminum content.

[0035] The core innovation of this application lies in optimizing the sealing operation and feeding parameters during the LF refining furnace feeding process, reducing oxygen exposure and aluminum oxidation during the feeding phase, thereby lowering the aluminum burnout rate. Specifically, this involves controlling the opening of the dust removal valve, sealing furnace holes, and using high-temperature resistant sealing materials to isolate the air. Furthermore, precise settings of the feeding depth, speed, and feed amount are combined to achieve efficient aluminum addition and minimize losses.

[0036] The working process and principle of the present application are a method for reducing the aluminum loss rate of aluminum-containing steel, and the process route includes KR stirring desulfurization-LD converter-post-furnace argon blowing treatment-LF refining furnace-CC continuous casting machine. In the wire feeding step in the LF refining furnace, first adjust the opening of the dust removal plug valve in the dust removal system, and close the temperature measurement sampling hole to reduce the entry of external air into the furnace. Then stop heating, cut off the power to the motor and raise or transfer the workstation to prepare for the wire feeding operation. After transferring the workstation, close the three-phase electrode hole to further seal the furnace body. Then open the wire feeding hole, and lower the wire feeding guide tube to the appropriate position. Select the appropriate wire feeding type, set the wire feeding speed, and start the wire feeding process. After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and finally the aluminum element burn-out rate is calculated.

[0037] This series of steps effectively reduces aluminum's exposure to oxygen by controlling the furnace environment and optimizing the wire feeding process, thereby lowering the aluminum's burnout rate. Adjusting the dust removal valve opening and closing various openings reduce air ingress. Stopping heating and relocating workstations mitigate the effects of high temperatures on aluminum. Precisely controlling the wire feeding process ensures even distribution of aluminum throughout the molten steel, reducing the risk of localized over-oxidation.

[0038] Example 1

[0039] This embodiment provides a method for reducing the aluminum loss rate of aluminum-containing steel. The process route is KR stirring desulfurization - LD converter - post-furnace argon blowing treatment - LF refining furnace and CC continuous casting machine, wherein the wire feeding step in the LF refining furnace is as follows:

[0040] S1. Adjust the opening of the dust removal valve in the dust removal system, close the temperature sampling hole, and control the opening of the dust removal valve at 25%. This ensures the reducing atmosphere in the refining furnace and reduces the amount of air intake during the refining process.

[0041] S2. Stop heating, control the temperature of the molten steel to 1550°C, and turn off the motor to raise or transfer the workstation;

[0042] S3. After the transfer station, the three-phase electrode holes are closed and sealed with electrode hole covers. During the refining process, when the three-phase electrodes are not inserted, the electrode hole covers are used to make the entire furnace cover close to a sealed state, thus forming a micro-vacuum environment to isolate the air and reduce the amount of gas absorbed by the molten steel;

[0043] S4 open the feed wire hole, feed wire conduit down, feed wire conduit down to a depth of 0.65 of the molten steel height, the feed wire conduit is perpendicular to the molten steel surface;

[0044] S5. Select the wire type and speed. Set the wire type to manganese alloy, the wire diameter to 15 mm, the speed to 1.9 m / min, and the wire quantity to 0.4 kg / t.

[0045] S6. After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and the aluminum element burning rate is calculated.

[0046] The calculation formula for the aluminum element burnout rate is as follows:

[0047]

[0048] Among them, the initial value of aluminum content in molten steel is the aluminum content in molten steel after deoxidation and alloying in converter;

[0049] End point value of aluminum content in molten steel: aluminum content in billets from continuous casting machines.

[0050] Through the above scheme, this application can effectively reduce the burn-off rate of aluminum in the LF refining furnace. By precisely controlling the dust removal system and sealing various holes, the opportunity for external air to enter the furnace is reduced, reducing the risk of aluminum oxidation. The optimized wire feeding process ensures that the aluminum is evenly distributed in the molten steel, reducing the possibility of localized over-oxidation. This method not only simplifies the production process, but also improves the production stability and molten steel quality of aluminum-containing steel, reduces the number of aluminum replenishments, reduces production costs, and improves the castability of the continuous casting molten steel.

[0051] Example 2

[0052] This embodiment provides a method for reducing the aluminum loss rate of aluminum-containing steel. The process route is KR stirring desulfurization - LD converter - post-furnace argon blowing treatment - LF refining furnace and CC continuous casting machine, wherein the wire feeding step in the LF refining furnace is as follows:

[0053] S1. Adjust the opening of the dust removal valve in the dust removal system, close the temperature sampling hole, and control the opening of the dust removal valve at 25%. This ensures the reducing atmosphere in the refining furnace and reduces the amount of air intake during the refining process.

[0054] S2. Stop heating, control the temperature of the molten steel to 1500℃, and turn off the power to the motor to raise or transfer the workstation;

[0055] S3. After the transfer station, the three-phase electrode holes are closed and sealed with electrode hole covers. During the refining process, when the three-phase electrodes are not inserted, the electrode hole covers are used to make the entire furnace cover close to a sealed state, thus forming a micro-vacuum environment to isolate the air and reduce the amount of gas absorbed by the molten steel;

[0056] S4 open the feed wire hole, feed wire conduit down, feed wire conduit down to a depth of 0.6 molten steel height, the feed wire conduit perpendicular to the molten steel surface;

[0057] S5. Select the wire type and speed. Set the wire type to aluminum alloy, the wire diameter to 6 mm, the wire speed to 1.8 m / min, and the wire quantity to 0.3 kg / t.

[0058] S6. After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and the aluminum element burning rate is calculated.

[0059] The calculation formula for the aluminum element burnout rate is as follows:

[0060]

[0061] Among them, the initial value of aluminum content in molten steel is the aluminum content in molten steel after deoxidation and alloying in converter;

[0062] End point value of aluminum content in molten steel: aluminum content in billets from continuous casting machines.

[0063] Example 3

[0064] This embodiment provides a method for reducing the aluminum loss rate of aluminum-containing steel. The process route is KR stirring desulfurization - LD converter - post-furnace argon blowing treatment - LF refining furnace and CC continuous casting machine, wherein the wire feeding step in the LF refining furnace is as follows:

[0065] S1. Adjust the opening of the dust removal valve in the dust removal system, close the temperature sampling hole, and control the opening of the dust removal valve at 30%. This ensures the reducing atmosphere in the refining furnace and reduces the amount of air intake during the refining process.

[0066] S2. Stop heating, control the temperature of the molten steel to 1500℃, and turn off the power to the motor to raise or transfer the workstation;

[0067] S3. After the transfer station, the three-phase electrode holes are closed and sealed with electrode hole covers. During the refining process, when the three-phase electrodes are not inserted, the electrode hole covers are used to make the entire furnace cover close to a sealed state, thus forming a micro-vacuum environment to isolate the air and reduce the amount of gas absorbed by the molten steel;

[0068] S4 open the feed wire hole, feed wire conduit down, feed wire conduit down to a depth of 0.7 molten steel height, the feed wire conduit perpendicular to the molten steel surface;

[0069] S5. Select the wire type and speed. The wire type is aluminum alloy, the wire diameter is 18 mm, the speed is 1.9 m / min, and the wire quantity is 0.45 kg / t.

[0070] S6. After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and the aluminum element burning rate is calculated.

[0071] The calculation formula for the aluminum element burnout rate is as follows:

[0072]

[0073] Among them, the initial value of aluminum content in molten steel is the aluminum content in molten steel after deoxidation and alloying in converter;

[0074] End point value of aluminum content in molten steel: aluminum content in billets from continuous casting machines.

[0075] Example 4

[0076] This embodiment provides a method for reducing the aluminum loss rate of aluminum-containing steel. The process route is KR stirring desulfurization - LD converter - post-furnace argon blowing treatment - LF refining furnace and CC continuous casting machine, wherein the wire feeding step in the LF refining furnace is as follows:

[0077] S1. Adjust the opening of the dust removal valve in the dust removal system, close the temperature sampling hole, and control the opening of the dust removal valve at 35%. This ensures the reducing atmosphere in the refining furnace and reduces the amount of air inhaled during the refining process.

[0078] S2. Stop heating, control the temperature of the molten steel to 1500℃, and turn off the power to the motor to raise or transfer the workstation;

[0079] S3. After the transfer station, the three-phase electrode holes are closed and sealed with electrode hole covers. During the refining process, when the three-phase electrodes are not inserted, the electrode hole covers are used to make the entire furnace cover close to a sealed state, thus forming a micro-vacuum environment to isolate the air and reduce the amount of gas absorbed by the molten steel;

[0080] S4 open the feed wire hole, feed wire conduit down, feed wire conduit down to a depth of 0.75 molten steel height, the feed wire conduit perpendicular to the molten steel surface;

[0081] S5. Select the wire type and feed speed. Set the wire type to manganese alloy, the wire diameter to 20 mm, the feed speed to 2 m / min, and the feed rate to 0.42 kg / t.

[0082] S6. After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and the aluminum element burning rate is calculated.

[0083] The calculation formula for the aluminum element burnout rate is as follows:

[0084]

[0085] Among them, the initial value of aluminum content in molten steel is the aluminum content in molten steel after deoxidation and alloying in converter;

[0086] End point value of aluminum content in molten steel: aluminum content in billets from continuous casting machines.

[0087] Comparative Example 1

[0088] The main technical feature that distinguishes this comparative example from Example 1 is that the opening of the gate valve is 10%.

[0089] Comparative Example 2

[0090] The technical feature that distinguishes this comparative embodiment from embodiment 1 is that the opening of the gate valve is 90%.

[0091] Comparative Example 3

[0092] The technical feature that distinguishes this comparative embodiment from embodiment 1 is that the three-phase electrode holes are not covered.

[0093] Results Statistics

[0094] The aluminum content in the samples was tested by sampling holes at three stages: the white slag making stage, after wire feeding, and after soft blowing. The results are shown in Table 2.

[0095] Table 2

[0096]

[0097] The aluminum loss rate of 10B22A steel production before and after the transformation from January to June 2023 was counted, and the average aluminum loss rate from January to June was calculated, as shown in Table 3.

[0098] Table 3

[0099]

[0100]

[0101] The average alloy content of 10B22A steel before and after the transformation from January to June 2023 is shown in Table 4.

[0102] Table 4

[0103]

[0104] Result Analysis

[0105] Through Examples 1-4 and Comparative Examples 1-3, combined with Tables 2, 3 and 4, it can be seen that after the wire feeding process is modified, the opening of the plug valve of the motor dust removal system is controlled at 25-35%, so that the reducing atmosphere in the refining furnace is guaranteed, and the air intake during the refining process is reduced; when the three-phase electrode is moved away from the workstation, the electrode hole cover is used to make the entire furnace cover close to a sealed state, so that a micro-vacuum environment can be formed to achieve the purpose of isolating the air, reducing the air intake of the molten steel, and avoiding excess air consumption of aluminum. After adjustment, the aluminum loss rate is reduced, among which the data of Example 3 is the best. It may be that under this condition, the oxidation of aluminum can be effectively avoided during the whole process. However, the aluminum loss rate between Examples 1-4 is not much different. This may be within the parameter range set in this application, which can well control the air intake and avoid excessive consumption of aluminum. Through Examples 1-4 and Comparative Examples 1-3, combined with Tables 2, 3 and 4, it can be seen that within the parameter range set in the present application, the aluminum loss rate can be well controlled to be below 40%, while the aluminum loss rates of Comparative Examples 1-3 are all above 40%. This may be because the opening of the dust removal system plug-in valve is too large or too small, and when the three-phase electrode is moved away from the work station, the electrode hole cover is not used to isolate the air, resulting in air entering and reacting with the aluminum for oxidation, which directly leads to an increase in the aluminum loss rate.

[0106] The above description is merely a preferred embodiment of the present application and does not constitute any form of limitation to the present application. Although the present application has been disclosed as above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to equivalent embodiments using the technical contents disclosed above without departing from the scope of the technical solution of the present application. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A method for reducing aluminum loss rate of aluminum-containing steel, the process route includes KR stirring desulfurization - LD converter - post-furnace argon blowing treatment - LF refining furnace - CC continuous casting machine, characterized in that: The feeding steps in the LF refining furnace are: Step S1. Adjust the opening of the dust removal valve in the dust removal system and close the temperature sampling hole; Step S2. Stop heating, turn off the motor power and raise or move the workstation; Step S3. After the workstation is transferred, the three-phase electrode holes are closed; Step S4. Open the wire feeding hole and lower the wire feeding conduit; Step S5. Select the wire feeding type and set the wire feeding speed; Step S6: After the wire feeding is completed, the wire feeding guide tube rises, the wire feeding hole is closed, and the aluminum element burnout rate is calculated.

2. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 1, characterized in that: The opening of the dust removal plug valve in S1 is controlled at 25-35%.

3. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 1, characterized in that: After stopping the heating in S2, the temperature of the molten steel in the refining furnace is 1500-1600°C.

4. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 1, characterized in that: The three-phase electrode holes in S3 are sealed with electrode hole covers, and the material of the electrode hole covers is nickel-based alloy.

5. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 1, characterized in that: The depth to which the wire feeding conduit is lowered in S4 is 0.6 to 0.75 of the depth of the molten steel, and the wire feeding conduit is perpendicular to the surface of the molten steel.

6. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 1, characterized in that: The type of wire to be fed in S5 is alloy wire, the diameter of the wire to be fed is 6-20 mm, the wire feeding speed is 1.8-2 m / min, and the wire feeding amount is 0.30-0.45 kg / t.

7. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 6, characterized in that: The alloy wire is a manganese alloy or an aluminum alloy.

8. The method for reducing aluminum loss rate of aluminum-containing steel according to claim 1, characterized in that: The calculation formula for the aluminum element burnout rate in S6 is as follows: Among them, the initial value of aluminum content in molten steel is the aluminum content in molten steel after deoxidation and alloying in converter; End point value of aluminum content in molten steel: aluminum content in billets from continuous casting machines.

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