CN110004268B - Method for producing low-carbon killed steel by carbon deoxidation process under normal pressure - Google Patents

Method for producing low-carbon killed steel by carbon deoxidation process under normal pressure Download PDF

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CN110004268B
CN110004268B CN201910397874.8A CN201910397874A CN110004268B CN 110004268 B CN110004268 B CN 110004268B CN 201910397874 A CN201910397874 A CN 201910397874A CN 110004268 B CN110004268 B CN 110004268B
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carbon
steel
deoxidizer
molten steel
slag
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CN110004268A (en
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梅雪辉
张晓军
吴春杰
李曙光
许海亮
温荣宇
赵晨光
郭猛
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Angang Steel Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/36—Processes yielding slags of special composition
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0006—Adding metallic additives
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0025—Adding carbon material
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/06—Deoxidising, e.g. killing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The invention relates to a method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure, wherein the upper limit of the carbon content of the low-carbon killed steel is 0.05-0.08% by mass, and the method comprises the following steps: the converter leaves carbon and performs boiling tapping, and the mass percentage of the end point carbon content is controlled according to the condition that the C is more than or equal to 0.04 percent and less than or equal to the upper limit of finished product carbon, namely-0.01 percent; treating in an LF furnace, blowing argon, then determining oxygen, firstly adding a first batch of slag to dilute the oxidability of top slag in a molten steel tank, and then adding a carbon deoxidizer; heating the electrode, and deoxidizing the carbide slag at high temperature by using lime, a carbon deoxidizer and an electric arc. The advantages are that: the carbon deoxidation reaction is mainly carried out in an LF furnace under normal pressure, and a carbon deoxidizer is used for replacing partial silicon and aluminum as the deoxidizer, so that the cost is reduced. Meanwhile, the carbon deoxidation does not leave deoxidation product residues in the molten steel, and is beneficial to improving the cleanliness of the molten steel.

Description

Method for producing low-carbon killed steel by carbon deoxidation process under normal pressure
Technical Field
The invention belongs to the field of steelmaking continuous casting refining, and particularly relates to a method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure.
Background
In the conventional steelmaking method, especially for producing low-carbon killed steel with carbon content not more than 0.08%, deoxidation is mainly completed by depending on elements such as silicon, aluminum and the like which have stronger affinity with oxygen than iron. These elements react with oxygen dissolved in the molten steel to form deoxidation products insoluble in the molten steel, and the oxygen content in the steel is reduced due to their floating out.
The carbon deoxidation process is mainly applied to vacuum conditions, and carbon and oxygen are reacted by using RH, VD and other vacuum refining equipment. Under the vacuum condition, the excess carbon in the molten steel can react with oxygen to produce carbon-oxygen reaction, so that the oxygen in the molten steel can be changed into CO to be removed, at this time, the carbon can be used as deoxidant under the vacuum condition, and its deoxidization capacity can be raised with the improvement of vacuum degree. However, the vacuum deoxidation method has high cost, and is commonly used for ultra-low carbon steel and high-grade pipeline steel with special requirements on gas content
The low-carbon killed steel with carbon content not more than 0.08% is produced under normal pressure, and generally, silicon-series alloy or aluminum-series alloy is added for deoxidation in the process of converter tapping, so that molten steel enters refining treatment after being killed. And a small amount of carburant is added in the tapping process of the converter for primary deoxidation, and then silicon deoxidation or aluminum deoxidation and alloying treatment are carried out. However, the foaming degree of the top slag is not easy to control, and the slag overflow risk is large. At present, silicon deoxidation or aluminum deoxidation is adopted to produce low-carbon killed steel, so that the production cost is higher.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide the low-carbon killed steel with the carbon content not more than 0.08 percent produced by the carbon deoxidation process under the normal pressure, and the carbide slag deoxidation is made at the high temperature by utilizing the carbon deoxidizer, the lime and the electrode heating, so that the heating efficiency is improved, the consumption of the deoxidizer is reduced, and the alloy cost is reduced. Reduction of Al2O3The molten steel cleanliness is improved.
In order to achieve the purpose, the invention is realized by the following technical scheme:
the method for producing the low-carbon killed steel by the carbon deoxidation process under the normal pressure comprises the following steps of:
1) making steel
a, leaving carbon in the converter, boiling and tapping, wherein the mass percent of the carbon content at the end point is controlled according to the mass percent of more than 0.04 percent and less than or equal to the upper limit of finished carbon of-0.01 percent;
b, controlling the clearance of the molten steel tank to be 400-600 mm;
2) refining
a, the molten steel reaches a pretreatment position of an LF furnace, and oxygen is determined after argon blowing;
b, after molten steel in a boiling state enters an LF furnace treatment position, firstly adding a first batch of slag material to dilute the oxidability of top slag in a molten steel tank, and then adding a carbon deoxidizer;
c, heating the electrode, namely performing high-temperature acetylene sludge deoxidation by using lime, a carbon deoxidizer and an electric arc, adding two batches of slag materials in the heating process, wherein the weight ratio of the lime to the slag melting agent in the two batches of slag materials is controlled to be 4: 1-5: 1; controlling the amount of the slag charge of the second batch to be 0-6 kg/ton steel;
and d, after the temperature is raised, adding a deoxidizing agent for final deoxidation, desulfurization, taking a process sample, alloying according to the process sample, finally adjusting the components, and casting on a machine.
In the step 1), a controls the end point carbon of the converter according to the upper limit of the finished carbon:
when the upper limit of finished carbon is 0.05-0.06%, the finished carbon does not contain 0.06%, and the end point carbon content of the converter is controlled to be 0.04-0.05% by mass;
when the upper limit of the finished carbon is 0.06% -0.08%, the mass percentage of the end point carbon content of the converter is controlled to be 0.04% -0.01% by mass (the upper limit of the finished carbon is-0.01%).
In the step 2), the first batch of slag charge and the adding amount thereof are 4-5 kg of lime per ton of steel and 2-2.5 kg of slag melting agent per ton of steel;
the adding amount of the carbon deoxidizer is determined according to the oxygen value at the station entry: the addition amount of the carbon deoxidizer is
The molten steel amount is x (the upper limit of finished product carbon-the carbon content in the molten steel + the fixed oxygen value/1000000-0.02%)/the carbon deoxidizer carbon content; wherein the unit of the constant oxygen value is ppm, and the range of the constant oxygen value is 200ppm-900 ppm.
The slagging agent in the step 2) is fluorite or bauxite or a slagging material taking bauxite as a main component; the carbon deoxidizer is a coke carburant or a petroleum coke carburant.
When the deoxidizer in the step 2) is an aluminum wire section, the produced low-carbon killed steel is low-carbon aluminum killed steel; after the temperature is increased, the number of the first batch of aluminum wire sections added according to the oxygen determination value is as follows:
when the arrival fixed oxygen value is less than or equal to 200ppm and less than 500ppm, adding 0.8-1.6 kg of aluminum line section per ton of steel into the LF furnace;
when the arrival fixed oxygen value is less than 800ppm and less than or equal to 500ppm, adding 1.6-2.1 kg of aluminum wire section per ton of steel into the LF furnace;
when the oxygen value is less than or equal to 800ppm, adding 2.1-2.5 kg of aluminum wire section per ton of steel into the LF furnace.
When the deoxidizer d in the step 2) is ferrosilicon, the produced low-carbon killed steel is low-carbon silicon killed steel; adding the first batch of ferrosilicon after temperature rise: the molten steel amount is multiplied by (the upper limit of finished product silicon-the silicon content in the molten steel)/the silicon-iron content.
Compared with the prior art, the invention has the beneficial effects that:
1. the carbon deoxidation reaction in the method for producing the low-carbon killed steel by the carbon deoxidation process under the normal pressure is mainly carried out in an LF furnace under the normal pressure. The carbon deoxidizer is used to replace partial silicon and aluminum as deoxidizer, so that the cost is reduced. Compared with the silicon deoxidation process and the aluminum deoxidation process which are commonly used at present, the cost per ton of steel can be reduced by 10-20 yuan. Meanwhile, the carbon deoxidation does not leave deoxidation product residues in the molten steel, and is beneficial to improving the cleanliness of the molten steel.
2. The invention uses the existing production equipment, adopts boiling molten steel to enter an LF furnace, and adds a carbon deoxidizer, lime and a slagging agent into the molten steel in a boiling state, and utilizes the carbon deoxidizer, the lime and the high temperature of an electrode to heat up to produce carbide slag for deoxidation.
3. The proportion of the lime of the first slag material of the LF furnace and the slagging agent is controlled, so that the carbide slag generated in the carbon deoxidation reaction process has a good submerged arc effect, and the electrode heating efficiency can be improved. And an electrode heating mode is adopted, and the heating rate of the LF furnace is increased from 3-5 ℃/min to 4-6 ℃/min.
4. In the LF process, a carbon deoxidizer is added to the boiling molten steel, so that slag overflow is likely to occur. The slag is added firstly to dilute the oxidability of the top slag in the molten steel tank, so that the slag overflow risk of adding a carbon deoxidizer is eliminated; the carbon deoxidation process can meet the normal production requirement.
5. The invention adopts a method of adding a carbon deoxidizer into molten steel according to a constant oxygen value, when the constant oxygen value is more than 200ppm, the carbon content of the added carbon deoxidizer and the carbon content in the molten steel exceed the upper limit of finished product carbon. The argon bubble blown in corresponds to a small vacuum chamber for the CO gas, and C and O in the molten steel react at the boundary of the argon bubble. After the treatment is finished, the carbon content of the molten steel is controlled within a finished product range, and the redundant carbon is used for deoxidation.
6. The method for adding the aluminum wire section into the molten steel according to the constant oxygen value can improve the accuracy of the first aluminum addition deoxidizer of the LF furnace and avoid the phenomenon of multiple aluminum addition deoxidizers caused by inaccurate first aluminum addition deoxidizer. Thereby ensuring the stable quality of the molten steel after the LF furnace is finished and the stable production of the LF furnace.
7. By adopting the method, the silicon return of the molten steel in the LF furnace treatment process can be reduced, and the low-silicon killed steel with the upper limit of 0.03 percent of the finished product silicon can be stably produced.
8. The operation of the LF is greatly influenced by the LF length experience and the molten steel entering the LF, the operation of the LF is modeled, the influence of human factors and the molten steel entering the LF on the operation of the LF is reduced, and the method is favorable for realizing the intelligent production of the LF.
Detailed Description
The present invention is described in detail below, but it should be noted that the practice of the present invention is not limited to the following embodiments.
The method for producing the low-carbon killed steel by the carbon deoxidation process under the normal pressure comprises the following steps of:
1) making steel
a, leaving carbon in the converter, boiling and tapping, wherein the mass percent of the carbon content at the end point is controlled according to the mass percent of more than 0.04 percent and less than or equal to the upper limit of finished carbon of-0.01 percent;
b, controlling the clearance of the molten steel tank to be 400-600 mm;
2) refining
a, the molten steel reaches a pretreatment position of an LF furnace, and oxygen is determined after argon blowing;
b, after molten steel in a boiling state enters an LF furnace treatment position, firstly adding a first batch of slag material to dilute the oxidability of top slag in a molten steel tank, and then adding a carbon deoxidizer;
c, heating the electrode for 5-10 minutes, deoxidizing the carbide slag at high temperature by using lime, a carbon deoxidizer and an electric arc, adding two batches of slag materials in the heating process, wherein the weight ratio of the lime to the slag melting agent in the two batches of slag materials is controlled to be 4: 1-5: 1; controlling the amount of the slag charge of the second batch to be 0-6 kg/ton steel;
d, after the temperature is raised, adding a deoxidizing agent for final deoxidation, desulfurization, taking a process sample, alloying according to the process sample, finally adjusting components, and casting on a machine;
in the step 1), a controls the end point carbon of the converter according to the upper limit of the finished carbon:
when the upper limit of finished carbon is 0.05-0.06%, the finished carbon does not contain 0.06%, and the mass percentage of the end point carbon content of the converter is controlled to be 0.04-0.05%;
when the upper limit of finished carbon is 0.06% -0.08%, the end point carbon content of the converter is controlled to be 0.04% -0.01% by mass (the upper limit of finished carbon is-0.01%);
the first batch of slag charge in the step 2) b and the adding amount thereof are 4-5 kg of lime per ton of steel and 2-2.5 kg of slag melting agent per ton of steel;
the adding amount of the carbon deoxidizer is determined according to the oxygen value at the station entry: the addition amount of the carbon deoxidizer is
The molten steel amount is x (the upper limit of finished product carbon-the carbon content in the molten steel + the fixed oxygen value/1000000-0.02%)/the carbon deoxidizer carbon content; wherein the unit of the constant oxygen value is ppm, and the range of the constant oxygen value is 200ppm-900 ppm.
The slagging agent in the step 2) is fluorite or bauxite or a slagging material taking bauxite as a main component; the carbon deoxidizer is a coke recarburizer or a petroleum coke recarburizer;
when the deoxidizer in the step 2) is an aluminum wire section, the produced low-carbon killed steel is low-carbon aluminum killed steel; after the temperature is increased, the number of the first batch of aluminum wire sections added according to the oxygen determination value is as follows:
when the arrival fixed oxygen value is less than or equal to 200ppm and less than 500ppm, adding 0.8-1.6 kg of aluminum line section per ton of steel into the LF furnace;
when the arrival fixed oxygen value is less than 800ppm and less than or equal to 500ppm, adding 1.6-2.1 kg of aluminum wire section per ton of steel into the LF furnace;
when the oxygen value is less than or equal to 800ppm, adding 2.1-2.5 kg of aluminum wire section per ton of steel into the LF furnace;
when the deoxidizer d in the step 2) is ferrosilicon, the produced low-carbon killed steel is low-carbon silicon killed steel; adding the first batch of ferrosilicon after temperature rise: the molten steel amount is multiplied by (the upper limit of finished product silicon-the silicon content in the molten steel)/the silicon-iron content.
Example one
A method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure comprises the following steps of:
1. steel-making process
1) The mass percentage of the end point carbon content of the converter is 0.04 percent;
2) tapping is carried out in a boiling way, and the clearance of the large tank is 400 mm.
2. Refining procedure
1. And (3) blowing argon for 2 minutes when the molten steel reaches a pretreatment position of the LF furnace, controlling the argon blowing amount to be more than 500L/min, closing the argon after top slag is melted, and determining oxygen, wherein the oxygen value is 600 ppm.
2. After molten steel enters an LF furnace treatment position, adding slag (4 kg/ton of steel white ash and 2 kg/ton of steel bauxite), and after the slag is completely melted, adding a carbon deoxidizer, wherein the adding amount of the carbon deoxidizer is x (the upper carbon limit of a finished product-the carbon content in the molten steel + 600/1000000-0.02%)/the carbon deoxidizer carbon content;
3. heating the electrode for 9 minutes, and blowing argon: 200L/min.
4. In the temperature rising process, adding the rest slag materials, wherein lime and bauxite in the rest slag materials are respectively 2 kg/ton steel and 0.5 kg/ton steel;
5. the first batch of aluminum wire segments was added at 1.9kg per ton of steel after the temperature was raised.
6. And (3) timely sticking and taking the slag sample, and when the slag sample changes color and is light green or transparent glass slag, taking the process sample and finally adjusting the components according to the process sample.
7. Molten steel is alloyed, then a steel aluminum calcium wire of 3 m/ton is fed, and the machine is operated for 3 minutes by blowing argon.
Example two
A method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure comprises the following steps of:
1. steel-making process
1) The mass percentage of the end point carbon content of the converter is 0.05 percent;
2) tapping is carried out in a boiling way, and the clearance of the large tank is 500 mm.
2. Refining procedure
1. And (3) blowing argon for 2 minutes when the molten steel reaches a pretreatment position of the LF furnace, controlling the argon blowing amount to be more than 500L/min, closing the argon after top slag is melted, and determining oxygen, wherein the oxygen value is 500 ppm.
2. After molten steel enters an LF furnace treatment position, adding slag (4.1 kg/ton steel white ash and 2.2 kg/ton steel bauxite), and after the slag is completely melted, adding a carbon deoxidizer, wherein the addition amount of the carbon deoxidizer is x (finished carbon upper limit-carbon content in molten steel + 500/1000000-0.02%)/carbon deoxidizer carbon content;
3. heating the electrode for 8 minutes, and blowing argon: 210L/min.
4. In the temperature rising process, adding the rest slag materials, wherein lime and bauxite in the rest slag materials are respectively 2.1 kg/ton steel and 0.5 kg/ton steel;
5. the first batch of aluminum wire segments was added at 1.6kg per ton of steel after the temperature was raised.
6. And (3) timely sticking and taking the slag sample, and when the slag sample changes color and is light green or transparent glass slag, taking the process sample and finally adjusting the components according to the process sample.
7. Molten steel is alloyed, then a steel aluminum calcium wire of 3 m/ton is fed, and the machine is operated for 3 minutes by blowing argon.
EXAMPLE III
A method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure comprises the following steps of:
1. steel-making process
1) The mass percentage of the carbon content at the end point of the converter is 0.06 percent;
2) tapping is carried out in a boiling way, and the clearance of the large tank is 500 mm.
2. Refining procedure
1. And (3) blowing argon for 3 minutes when the molten steel reaches a pretreatment position of the LF furnace, controlling the argon blowing amount to be more than 500L/min, closing the argon after top slag is melted, and determining oxygen, wherein the oxygen value is 500 ppm.
2. After molten steel enters an LF furnace treatment position, adding slag (5 kg/ton of steel white ash and 2.5 kg/ton of steel bauxite), and after the slag is completely melted, adding a carbon deoxidizer, wherein the addition amount of the carbon deoxidizer is x (the upper carbon limit of a finished product-the carbon content in the molten steel + 500/1000000-0.02%)/the carbon deoxidizer carbon content.
3. Heating the electrode for 8 minutes, and blowing argon: 150L/min.
4. In the temperature rising process, adding the rest slag materials, wherein lime and bauxite in the rest slag materials are respectively 2.2 kg/ton steel and 0.5 kg/ton steel;
5. the first batch of aluminum wire segments was added at 1.6kg per ton of steel after the temperature was raised.
6. And (3) timely sticking and taking the slag sample, and when the slag sample changes color and is light green or transparent glass slag, taking the process sample and finally adjusting the components according to the process sample.
7. After molten steel is alloyed, feeding 2.5 m/ton steel aluminum calcium wire, blowing argon for 3 minutes and loading.
Example four
A method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure comprises the following steps of:
1. steel-making process
1) The mass percentage of the end point carbon content of the converter is 0.05 percent;
2) tapping is carried out in a boiling way, and the clearance of the big tank is 600 mm.
2. Refining procedure
1. And (3) blowing argon for 2 minutes when the molten steel reaches a pretreatment position of the LF furnace, controlling the argon blowing amount to be more than 500L/min, closing the argon after top slag is melted, and determining oxygen, wherein the oxygen value is 550 ppm.
2. After molten steel enters an LF furnace treatment position, adding slag (4.5 kg/ton steel white ash and 2.5 kg/ton steel bauxite), and after the slag is completely melted, adding a carbon deoxidizer, wherein the addition amount of the carbon deoxidizer is x (finished carbon upper limit-carbon content in molten steel + 550/1000000-0.02%)/carbon deoxidizer carbon content.
3. Heating the electrode for 10 minutes, and blowing argon: 350L/min.
4. In the temperature rising process, adding the rest slag materials, wherein lime and bauxite in the rest slag materials are 1.8 kg/ton steel and 0.4 kg/ton steel respectively;
5. the first batch of aluminum wire segments was added at 1.7 kg/ton steel after the temperature was raised.
6. And (3) timely sticking and taking the slag sample, and when the slag sample changes color and is light green or transparent glass slag, taking the process sample and finally adjusting the components according to the process sample.
7. Molten steel is alloyed, then a steel aluminum calcium wire of 3 m/ton is fed, and the machine is operated for 3 minutes by blowing argon.
EXAMPLE five
A method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure comprises the following steps of:
1. steel-making process
1) The mass percentage of the carbon content at the end point of the converter is controlled to be 0.04 percent;
2) tapping is carried out in a boiling way, and the clearance of the large tank is 500 mm.
2. Refining procedure
1. And (3) blowing argon for 3 minutes when the molten steel reaches a pretreatment position of the LF furnace, controlling the argon blowing amount to be more than 500L/min, closing the argon after top slag is melted, and determining oxygen, wherein the oxygen value is 700 ppm.
2. After molten steel enters an LF furnace treatment position, adding slag (4.5 kg/ton of steel white ash and 2 kg/ton of steel bauxite), and after the slag is completely melted, adding a carbon deoxidizer, wherein the adding amount of the carbon deoxidizer is x (the upper carbon limit of a finished product-the carbon content in the molten steel + 700/1000000-0.02%)/the carbon deoxidizer carbon content.
3. Heating the electrode for 7 minutes, and blowing argon: 230L/min, and the submerged arc effect is ensured.
4. In the temperature rising process, adding the rest slag materials, wherein the lime and the bauxite in the rest slag materials are respectively 1.3 kg/ton steel and 0.3 kg/ton steel;
5. after the temperature is raised, the adding amount of the first batch of ferrosilicon is the molten steel amount multiplied by (the upper limit of finished product silicon-the silicon content in the molten steel)/the silicon content of the ferrosilicon.
6. And (3) timely sticking and taking the slag sample, and when the slag sample changes color and is light green or transparent glass slag, taking the process sample and finally adjusting the components according to the process sample.
7. After molten steel is alloyed, feeding a steel silicon-calcium wire of 2 m/ton, and blowing argon for 3 minutes to machine.
EXAMPLE six
A method for producing low-carbon killed steel by a carbon deoxidation process under normal pressure comprises the following steps of:
1. steel-making process
1) Controlling the mass percentage of the carbon content at the end point of the converter to be 0.07%;
2) tapping is carried out in a boiling way, and the clearance of the large tank is 400 mm.
2. Refining procedure
1. And (3) blowing argon for 3 minutes when the molten steel reaches a pretreatment position of the LF furnace, controlling the argon blowing amount to be more than 500L/min, closing the argon after top slag is melted, and determining oxygen, wherein the oxygen value is 400 ppm.
2. After molten steel enters an LF furnace treatment position, adding slag (5 kg/ton of steel white ash and 2.5 kg/ton of steel bauxite), and after the slag is completely melted, adding a carbon deoxidizer, wherein the addition amount of the carbon deoxidizer is x (the upper carbon limit of a finished product-the carbon content in the molten steel + 400/1000000-0.02%)/the carbon deoxidizer carbon content.
3. Heating the electrode for 8 minutes, and blowing argon: 260L/min, and ensuring the submerged arc effect.
4. In the temperature rising process, adding the rest slag materials, wherein lime and bauxite in the rest slag materials are respectively 2 kg/ton steel and 0.4 kg/ton steel;
5. after the temperature is raised, the adding amount of the first batch of ferrosilicon is the molten steel amount multiplied by (the upper limit of finished product silicon-the silicon content in the molten steel)/the silicon content of the ferrosilicon.
6. And (3) timely sticking and taking the slag sample, and when the slag sample changes color and is light green or transparent glass slag, taking the process sample and finally adjusting the components according to the process sample.
7. After molten steel is alloyed, feeding a steel silicon-calcium wire of 2 m/ton, and blowing argon for 3 minutes to machine.

Claims (6)

1. The method for producing the low-carbon killed steel by the carbon deoxidation process under the normal pressure is characterized in that the mass percentage of the upper limit of the carbon content of the low-carbon killed steel is 0.05-0.08%, and the method comprises the following steps:
1) making steel
a, leaving carbon in the converter, boiling and tapping, wherein the mass percent of the carbon content at the end point is controlled according to the mass percent of more than 0.04 percent and less than or equal to the upper limit of finished carbon of-0.01 percent;
b, controlling the clearance of the molten steel tank to be 400-600 mm;
2) refining
a, the molten steel reaches a pretreatment position of an LF furnace, and oxygen is determined after argon blowing;
b, in the LF procedure, a carbon deoxidizer is added into the boiling molten steel, so that slag overflow is easy to occur; after molten steel in a boiling state enters an LF furnace treatment position, adding a first batch of slag material to dilute the oxidability of top slag in a molten steel tank, thereby eliminating the risk of slag overflow by adding a carbon deoxidizer; then adding a carbon deoxidizer according to the arrival oxygen determination value;
when the constant oxygen value is more than 200ppm, the carbon content of the added carbon deoxidizer and the carbon content in the molten steel exceed the upper limit of finished product carbon; the blown-in argon bubble is equivalent to a small vacuum chamber for CO gas, and C and O in the molten steel react on the boundary of the argon bubble; after the treatment is finished, controlling the carbon content of the molten steel within a finished product range, and using redundant carbon for deoxidation;
the carbon deoxidizer is a coke carburant or a petroleum coke carburant;
c, heating the electrode, namely performing high-temperature acetylene sludge deoxidation by using lime, a carbon deoxidizer and an electric arc, adding two batches of slag materials in the heating process, wherein the weight ratio of the lime to the slag melting agent in the two batches of slag materials is controlled to be 4: 1-5: 1; controlling the amount of the slag charge of the second batch to be 0-6 kg/ton steel;
and d, after the temperature is raised, adding a deoxidizing agent for final deoxidation, desulfurization, taking a process sample, alloying according to the process sample, finally adjusting the components, and casting on a machine.
2. The method for producing the low-carbon killed steel by the atmospheric-pressure carbon deoxidation process according to claim 1, wherein in the step 1), a controls the end point carbon of the converter according to the upper limit of finished carbon:
when the upper limit of finished carbon is 0.05-0.06%, the finished carbon does not contain 0.06%, and the end point carbon content of the converter is controlled to be 0.04-0.05% by mass;
when the upper limit of the finished carbon is 0.06% -0.08%, the mass percentage of the end point carbon content of the converter is controlled to be 0.04% -0.01% by mass (the upper limit of the finished carbon is-0.01%).
3. The method for producing the low-carbon killed steel by the atmospheric-pressure carbon deoxidation process according to claim 1, wherein the first slag charge and the addition amount thereof in the step b) are 4-5 kg of lime per ton of steel and 2-2.5 kg of slagging agent per ton of steel;
the adding amount of the carbon deoxidizer is determined according to the oxygen value at the station entry: the addition amount of the carbon deoxidizer is
The molten steel amount is x (the upper limit of finished product carbon-the carbon content in the molten steel + the fixed oxygen value/1000000-0.02%)/the carbon deoxidizer carbon content; wherein the unit of the constant oxygen value is ppm, and the range of the constant oxygen value is 200ppm-900 ppm.
4. The method for producing the low-carbon killed steel by the atmospheric-pressure carbon deoxidation process as claimed in claim 1, wherein the slagging agent in the step 2) is fluorite or bauxite or a slagging material with bauxite as a main component.
5. The method for producing the low-carbon killed steel by the atmospheric-pressure carbon deoxidation process as claimed in claim 1, wherein when the deoxidizer of d) in the step 2) is an aluminum wire section, the produced low-carbon killed steel is low-carbon aluminum killed steel; after the temperature is increased, the number of the first batch of aluminum wire sections added according to the oxygen determination value is as follows:
when the arrival fixed oxygen value is less than or equal to 200ppm and less than 500ppm, adding 0.8-1.6 kg of aluminum line section per ton of steel into the LF furnace;
when the arrival fixed oxygen value is less than 800ppm and less than or equal to 500ppm, adding 1.6-2.1 kg of aluminum wire section per ton of steel into the LF furnace;
when the oxygen value is less than or equal to 800ppm, adding 2.1-2.5 kg of aluminum wire section per ton of steel into the LF furnace.
6. The method for producing the low-carbon killed steel by the atmospheric-pressure carbon deoxidation process according to claim 1, wherein when the deoxidizer d in the step 2) is ferrosilicon, the produced low-carbon killed steel is low-carbon silicon killed steel; adding the first batch of ferrosilicon after temperature rise: the molten steel amount is multiplied by (the upper limit of finished product silicon-the silicon content in the molten steel)/the silicon-iron content.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102134628A (en) * 2011-03-04 2011-07-27 河北钢铁股份有限公司承德分公司 Smelting method of low-carbon aluminium killed steel with low silicon content
CN107794342A (en) * 2016-09-06 2018-03-13 鞍钢股份有限公司 A kind of method that LF refining efficiently utilizes calcium carbide

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102134628A (en) * 2011-03-04 2011-07-27 河北钢铁股份有限公司承德分公司 Smelting method of low-carbon aluminium killed steel with low silicon content
CN107794342A (en) * 2016-09-06 2018-03-13 鞍钢股份有限公司 A kind of method that LF refining efficiently utilizes calcium carbide

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
CaC2在低碳含铝钢脱氧工艺中的应用;安增卫等;《河北冶金》;20121231(第5期);第33-34页 *
低碳含铝钢LF 炉精炼工艺及精炼渣的优化;王谦等;《北京科技大学学报》;20070630;第29卷;第14-17页 *

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