CN114045376A - Method for desulfurizing molten steel in converter tapping process - Google Patents
Method for desulfurizing molten steel in converter tapping process Download PDFInfo
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- CN114045376A CN114045376A CN202111209008.5A CN202111209008A CN114045376A CN 114045376 A CN114045376 A CN 114045376A CN 202111209008 A CN202111209008 A CN 202111209008A CN 114045376 A CN114045376 A CN 114045376A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 131
- 239000010959 steel Substances 0.000 title claims abstract description 131
- 238000010079 rubber tapping Methods 0.000 title claims abstract description 61
- 238000000034 method Methods 0.000 title claims abstract description 55
- 230000008569 process Effects 0.000 title claims abstract description 25
- 230000003009 desulfurizing effect Effects 0.000 title claims abstract description 19
- 239000002893 slag Substances 0.000 claims abstract description 76
- 238000005266 casting Methods 0.000 claims abstract description 62
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 30
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims abstract description 25
- 235000011941 Tilia x europaea Nutrition 0.000 claims abstract description 25
- 239000004571 lime Substances 0.000 claims abstract description 25
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 24
- 229910052786 argon Inorganic materials 0.000 claims abstract description 15
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 21
- 229910052782 aluminium Inorganic materials 0.000 claims description 21
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 20
- 239000002245 particle Substances 0.000 claims description 18
- 238000003756 stirring Methods 0.000 claims description 14
- 229910052681 coesite Inorganic materials 0.000 claims description 10
- 229910052906 cristobalite Inorganic materials 0.000 claims description 10
- 239000012535 impurity Substances 0.000 claims description 10
- 239000000377 silicon dioxide Substances 0.000 claims description 10
- 229910052682 stishovite Inorganic materials 0.000 claims description 10
- 229910052905 tridymite Inorganic materials 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 9
- 229910052593 corundum Inorganic materials 0.000 claims description 9
- 239000007789 gas Substances 0.000 claims description 9
- 229910001845 yogo sapphire Inorganic materials 0.000 claims description 9
- 238000012216 screening Methods 0.000 claims description 7
- 239000000126 substance Substances 0.000 claims description 4
- 238000001816 cooling Methods 0.000 claims description 3
- 238000006477 desulfuration reaction Methods 0.000 abstract description 19
- 230000023556 desulfurization Effects 0.000 abstract description 19
- 238000003723 Smelting Methods 0.000 abstract description 18
- 239000011593 sulfur Substances 0.000 abstract description 14
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 abstract description 13
- 238000009628 steelmaking Methods 0.000 abstract description 7
- 238000002844 melting Methods 0.000 abstract description 6
- 230000008018 melting Effects 0.000 abstract description 6
- 238000007664 blowing Methods 0.000 abstract description 5
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 230000000052 comparative effect Effects 0.000 description 10
- 230000000694 effects Effects 0.000 description 9
- 230000008901 benefit Effects 0.000 description 5
- 230000004048 modification Effects 0.000 description 5
- 238000012986 modification Methods 0.000 description 5
- 229910001208 Crucible steel Inorganic materials 0.000 description 4
- 238000004064 recycling Methods 0.000 description 4
- 238000007670 refining Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 239000004576 sand Substances 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000002440 industrial waste Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 229910000532 Deoxidized steel Inorganic materials 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- -1 casting residue Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000003607 modifier Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
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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
- 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
-
- 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
-
- 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
- C21C7/064—Dephosphorising; Desulfurising
-
- 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
- C21C7/064—Dephosphorising; Desulfurising
- C21C7/0645—Agents used for dephosphorising or desulfurising
-
- 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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- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
The invention particularly relates to a method for desulfurizing molten steel in the process of converter tapping, which belongs to the technical field of converter steelmaking, and utilizes the characteristics of high alkalinity and high sulfur capacity and quick slag melting of premelting slag of the molten steel to add casting residue, lime and a deoxidizer into a steel ladle along with steel flow in the process of converter tapping, and controls proper bottom blowing argon flow and bottom blowing time of the steel ladle to further promote desulfurization reaction between slag and steel after tapping, so that the desulfurization rate is improved to more than 65 percent in the process of converter tapping on the premise of not prolonging the smelting period.
Description
Technical Field
The invention belongs to the technical field of converter steelmaking, and particularly relates to a method for desulfurizing molten steel in the converter tapping process.
Background
The LF refining slag of the aluminum deoxidized steel has the characteristics of high alkalinity, high oxidability and low melting point, and if the residual steel slag after the continuous casting is finished is treated as waste slag, the problem of environmental pollution is brought on one hand, and the resource waste is caused on the other hand. Through experimental research on processing and recycling of the cast steel slag, the cold-state cast steel slag is recycled, and remarkable economic and social benefits are obtained.
For the cast steel slag residue, the most efficient application technology is the method of directly returning the thermal-state cast steel slag residue to the LF furnace for recycling. After the refined molten steel is cast, the temperature of hot slag in a ladle is 1525-1550 ℃. When the hot steel slag is recycled, lime or other refining slag materials are properly added at the top of the steel ladle according to actual conditions, so that the heat loss when the molten slag is melted is reduced, the molten steel heating time is shortened, the electric energy is saved, and the consumption of lime and a slagging agent is reduced. However, the direct recovery of the hot-state casting residue requires the on-site equipment capability, such as the logistics facilities of crane dispatching and transportation. If the conditions cannot be met, the hot casting residues are poured into a residue pit for cooling and stacking, so that for the cooled casting residues, a high-efficiency application technology is needed to be developed, the discharge of industrial waste is reduced, and the recycling of waste residues is realized.
Disclosure of Invention
The invention aims to provide a method for desulfurizing molten steel in the tapping process of a converter, which aims to solve the problem that the cooled casting residue cannot be utilized at present.
The embodiment of the invention provides a method for desulfurizing molten steel in a converter tapping process, which comprises the following steps:
obtaining cold-state casting residue; the chemical components of the cold-state casting slag comprise the following components in percentage by mass: 50 to 55 percent of CaO and SiO25％～10％、Al2O320 to 30 percent of MgO, 5 to 8 percent of MgO, 0.2 to 0.7 percent of S, less than or equal to 2 percent of water, less than 1 percent of FeO and MnO, and the balance of inevitable impurities;
adding molten steel into the cold-state casting residue, the small-particle lime and the deoxidizer in the tapping process to obtain deoxidized molten steel;
and after tapping is finished, increasing the flow of bottom-blown argon to stir the deoxidized molten steel to obtain desulfurized molten steel.
Optionally, the cold-state casting slag, the small-sized lime and the deoxidizer are added into molten steel in the tapping process to obtain deoxidized molten steel, and the adding time is before tapping 1/5.
Optionally, the amount of the cold-state casting slag added in each ton of steel is 6Kg-8 Kg.
Optionally, the particle size of the cold-state casting slag is 5mm-30 mm.
Optionally, the small lime is added in an amount of 2Kg to 4Kg per ton of steel.
Optionally, the deoxidizer is a steel grit aluminum deoxidizer, and the steel grit aluminum deoxidizer is used for controlling the mass percentage of aluminum dissolved in the deoxidized molten steel to be 0.03-0.05%.
Optionally, the obtaining of the cold-state casting slag specifically includes:
and cooling the hot-state casting slag after casting, and then crushing and screening to obtain cold-state casting slag.
Optionally, in the tapping process, the slag thickness of the converter slag is controlled to be less than 0.7 m.
Optionally, the flow rate of the bottom-blown argon gas is 300NL/min-400 NL/min.
Optionally, the stirring time is 2min-4 min.
One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:
the method for desulfurizing molten steel in the converter tapping process, provided by the embodiment of the invention, comprises the following steps: obtaining cold-state casting residue; the chemical components of the cold-state casting slag comprise the following components in percentage by mass: 50 to 55 percent of CaO and SiO2 5％～10％、Al2O320 to 30 percent of MgO, 5 to 8 percent of MgO, 0.2 to 0.7 percent of S, less than or equal to 2 percent of water, less than 1 percent of FeO and MnO, and the balance of inevitable impurities; adding molten steel into the cold-state casting residue, the small-particle lime and the deoxidizer in the tapping process to obtain deoxidized molten steel; after tapping is finished, increasing the flow of bottom-blown argon to stir the deoxidized molten steel to obtain desulfurized molten steel; by utilizing the characteristics of high alkalinity and high sulfur capacity and quick slag melting of pre-melted slag, casting residue, lime and a deoxidizer are added into a steel ladle along with steel flow in the tapping process of the converter, the proper bottom blowing argon flow and bottom blowing time of the steel ladle are controlled after tapping to further promote the desulfurization reaction between slag and steel, and the desulfurization rate is improved to more than 65 percent in the tapping process of the converter on the premise of not prolonging the smelting period.
The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
Fig. 1 is a flow chart of a method provided by an embodiment of the invention.
Detailed Description
The present invention will be described in detail below with reference to specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly apparent therefrom. It will be understood by those skilled in the art that these specific embodiments and examples are for the purpose of illustrating the invention and are not to be construed as limiting the invention.
Throughout the specification, unless otherwise specifically noted, terms used herein should be understood as having meanings as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.
Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.
In order to solve the technical problems, the general idea of the embodiment of the application is as follows:
according to an exemplary embodiment of the present invention, there is provided a method of desulfurizing molten steel during tapping of a converter, the method including:
s1, obtaining cold-state casting slag; the chemical components of the cold-state casting slag comprise the following components in percentage by mass: 50 to 55 percent of CaO and SiO2 5％～10％、Al2O320 to 30 percent of MgO, 5 to 8 percent of MgO, 0.2 to 0.7 percent of S, less than or equal to 2 percent of water, less than 1 percent of FeO and MnO, and the balance of inevitable impurities;
specifically, the cast hot-state casting slag is cooled and then crushed and sieved to obtain cold-state casting slag.
As an alternative embodiment, the particle size of the cold casting residue is 5mm to 30 mm.
The particle size of the cold-state casting residue is controlled to be 5mm-30mm, so that rapid slagging is facilitated, the particle size is too large to facilitate slagging and influence the desulfurization effect, and the particle size is too small to facilitate pulverization and to be impacted into a lump by molten steel, and is also not beneficial to slagging.
S2, adding molten steel into the cold-state casting slag, the small-particle lime and the deoxidizer in a tapping process to obtain deoxidized molten steel;
as an alternative embodiment, the cold casting residue, the small-sized lime and the deoxidizer are added into molten steel during tapping to obtain deoxidized molten steel, wherein the adding time is before tapping 1/5.
As an alternative embodiment, the cold-state casting residue is added in an amount of 6Kg to 8Kg per ton of steel.
The cold-state casting residue of 6-8 Kg/t steel is added along with the steel flow before the converter tapping 1/5 is controlled, so that the slag melting can be promoted under the impact stirring action of the steel flow, the slag steel is fully contacted as much as possible for desulfurization reaction, the temperature of the molten steel is greatly reduced due to the excessively large adding amount, the desulfurization efficiency is influenced, the slag amount is small due to the excessively small value, and the desulfurization amount is influenced.
As an alternative embodiment, the small lime particles are added in an amount of 2Kg to 4Kg per ton of steel. The components of the small lime particles include, in mass fraction, CaO 90% or more and SiO2Less than or equal to 2 percent, less than or equal to 5 percent of MgO, less than or equal to 0.02 percent of S, less than or equal to 0.02 percent of P, less than or equal to 1.0 percent of water, and the balance of inevitable impurities, wherein the grain diameter of the small lime particles is 3mm-10 mm.
The lime of steel of 2-4 Kg/t is added along with the steel flow before the converter tapping 1/5 is controlled, the lime and the casting slag are promoted to fully contact and melt the slag under the impact stirring action of the steel flow, the slag steel fully contacts and carries out the desulfurization reaction as much as possible, the adverse effect of overlarge adding amount value is that the slag is not easily melted, the CaO content in the slag is reduced due to the overlong value, the sulfur capacity of the slag is reduced, and the desulfurization is not facilitated.
As an optional implementation mode, the adding amount of the steel grit aluminum deoxidizer is adjusted according to the oxygen content of the molten steel during tapping, and the mass percentage of the dissolved aluminum in the molten steel after tapping deoxidation is ensured to be 0.03-0.05%.
As an alternative embodiment, the slag thickness of the converter slag is controlled to be less than 0.7m during the tapping process.
The reason for controlling the slag thickness of the converter slag to be less than 0.7m is that the converter slag is oxidizing slag and is not beneficial to desulfurization, and the adverse effect of overlarge thickness value is that the slag amount is increased, the oxidizing property of the slag is improved, the using amount of a slag deoxidation modifier is increased, and the cost is increased.
And S3, after tapping is finished, increasing the flow of bottom-blown argon to stir the deoxidized molten steel to obtain desulfurized molten steel.
As an alternative embodiment, the flow rate of the argon bottom-blown gas is 300NL/min-400NL/min, and the stirring time is 2min-4 min.
The method for desulfurizing molten steel during tapping of a converter according to the present application will be described in detail below with reference to examples, comparative examples and experimental data.
Example 1
Smelting in a converter with nominal capacity of 210t, wherein the smelting steel grade is Q345 DH.
The granularity of the cold-state casting residue after crushing and screening is 5-30 mm, and the cold-state casting residue comprises the following components in percentage by mass: CaO: 54.8% of SiO2：8.1％，Al2O3: 28.6%, MgO: 6.8%, FeO + MnO: 0.89%, S: 0.6 percent, less than or equal to 2 percent of water and the balance of impurity components which do not influence the steelmaking process.
The mass fraction of sulfur in molten steel at the smelting end point of the converter is 0.0227%, the thickness of slag discharged from the converter is 0.5m, the tapping temperature of the converter is 1650 ℃, 6.8Kg/t of cold-state casting slag of steel, 2.7Kg/t of small-particle lime of steel and 2.6Kg/t of steel sand aluminum are added along with steel flow to carry out deoxidation and slag making, the flow of argon gas blown from the bottom of a single way of a steel ladle after tapping is 350NL/min, stirring is carried out for 3min, and the mass fraction of dissolved aluminum in the molten steel is 0.040% and the mass fraction of sulfur is 0.0073%.
Example 2
Smelting in a converter with nominal capacity of 210t, wherein the smelting steel grade is 16 MnR.
The granularity of the cold-state casting residue after crushing and screening is 5-30 mm, and the cold-state casting residue comprises the following components in percentage by mass: CaO: 52.8% of SiO2：6.8％，Al2O3: 29.6%, MgO: 7.4%, FeO + MnO: 0.91%, S: 0.5 percent, less than or equal to 2 percent of water and the balance of impurity components which do not influence the steelmaking process.
The mass fraction of sulfur in molten steel at the smelting end point of the converter is 0.0164%, the slag thickness of slag discharged from the converter is 0.4m, the tapping temperature of the converter is 1649 ℃, 7.1Kg/t of cold-state casting slag of steel, 3.2Kg/t of small-particle lime of steel and 2.8Kg/t of steel sand aluminum are added along with steel flow to carry out deoxidation and slagging in 1/5, the flow of argon gas blown from the bottom of a single way of a steel ladle after tapping is NL 376/min, stirring is carried out for 3min, and the mass fraction of dissolved aluminum in the molten steel is 0.047% and the mass fraction of sulfur is 0.0056%.
Comparative example 1
Smelting in a converter with nominal capacity of 210t, wherein the smelting steel grade is Q345 DH.
The granularity of the cold-state casting residue after crushing and screening is 5-30 mm, and the cold-state casting residue comprises the following components in percentage by mass: CaO: 54.8% of SiO2：8.1％，Al2O3: 28.6%, MgO: 6.8%, FeO + MnO: 0.89%, S: 0.6 percent, less than or equal to 2 percent of water and the balance of impurity components which do not influence the steelmaking process.
The mass fraction of sulfur in molten steel at the smelting end point of the converter is 0.0227%, the thickness of slag discharged from the converter is 0.5m, the tapping temperature of the converter is 1650 ℃, 5Kg/t of cold-state casting slag of steel, 1.5Kg/t of small-particle lime of steel and 2.6Kg/t of steel grit aluminum are added along with steel flow to carry out deoxidation and slagging, the flow of argon gas blown from one way of the bottom of a steel ladle after tapping is 350NL/min, and the molten steel is stirred for 3min, wherein the mass fraction of dissolved aluminum in the molten steel is 0.040% and the mass fraction of sulfur is 0.0116%.
Comparative example 2
Smelting in a converter with nominal capacity of 210t, wherein the smelting steel grade is Q345 DH.
The granularity of the cold-state casting residue after crushing and screening is 5-30 mm, and the cold-state casting residue comprises the following components in percentage by mass: CaO: 54.8% of SiO2：8.1％，Al2O3: 28.6%, MgO: 6.8%, FeO + MnO: 0.89%, S: 0.6 percent, less than or equal to 2 percent of water and the balance of impurity components which do not influence the steelmaking process.
The mass fraction of sulfur in molten steel at the smelting end point of the converter is 0.0227%, the thickness of slag discharged from the converter is 0.5m, the tapping temperature of the converter is 1650 ℃, 8.5Kg/t of cold-state casting slag of steel, 5Kg/t of small-particle lime of steel and 2.6Kg/t of steel grit aluminum are added along with steel flow to carry out deoxidation and slagging, the flow of argon gas blown from one bottom of a steel ladle after tapping is 350NL/min, the molten steel is stirred for 3min, and the mass fraction of dissolved aluminum in the molten steel is 0.040% and the mass fraction of sulfur is 0.0096%.
Comparative example 3
Smelting in a converter with nominal capacity of 210t, wherein the smelting steel grade is 16 MnR.
The granularity of the cold-state casting residue after crushing and screening is 5-30 mm, and the cold-state casting residue comprises the following components in percentage by mass: CaO: 52.8% of SiO2：6.8％，Al2O3: 29.6%, MgO: 7.4%, FeO + MnO: 0.91%, S: 0.5 percent, less than or equal to 2 percent of water and the balance of impurity components which do not influence the steelmaking process.
The mass fraction of sulfur in molten steel at the smelting end point of the converter is 0.0164%, the slag thickness of slag discharged from the converter is 0.4m, the tapping temperature of the converter is 1649 ℃, 7.1Kg/t of cold-state casting slag of steel, 3.2Kg/t of small-particle lime of steel and 2.8Kg/t of steel sand aluminum are added along with steel flow to carry out deoxidation and slagging in 2/5, the flow of argon gas blown from the bottom of a single way of a steel ladle after tapping is NL 376/min, stirring is carried out for 3min, and the mass fraction of dissolved aluminum in the molten steel is 0.047% and the mass fraction of sulfur is 0.0072%.
The desulfurization results of examples 1-2 and comparative examples 1-2 are shown in the following table:
| desulfurization rate | |
| Example 1 | 67.8％ |
| Example 2 | 65.9％ |
| Comparative example 1 | 48.9％ |
| Comparative example 2 | 57.7％ |
| Comparative example 3 | 56.1％ |
From the above table, by adopting the method provided by the embodiment of the invention, the desulfurization rate in the tapping process of the converter is improved to more than 65%, and by comparing the data of the comparative examples 1 and 2 with the data of the embodiment, when the addition amount of the cold-state casting residue is not in the range provided by the embodiment of the invention, the desulfurization effect is reduced when the addition amount is too small, and when the addition amount is too large, the temperature is reduced to a large extent, the slagging effect is influenced, and the desulfurization capability is further influenced. As can be seen from comparison of the data in comparative example 3 with those in the examples, when the cold-state casting slag is not added within the range provided by the examples of the present invention, the impact stirring effect which cannot be reused in the molten steel tapping process to promote slag melting occurs too late, and the contact reaction time between the slag steels is reduced, which affects the desulfurization efficiency.
One or more technical solutions in the embodiments of the present invention at least have the following technical effects or advantages:
(1) according to the method provided by the embodiment of the invention, on the premise of not increasing the smelting period, the cold-state casting residue, lime and steel grit aluminum deoxidizer are added along with steel flow in the converter tapping process by utilizing the high-alkalinity and high-sulfur capacity performance of the cold-state casting residue, and the desulfurization reaction between slag and steel is promoted by utilizing the function of argon gas blowing and stirring at the bottom of a steel ladle, so that the desulfurization rate in the converter tapping process is improved to more than 65%;
(2) the method provided by the embodiment of the invention utilizes the performance that the pre-melted slag of the cold-state casting residue is easy to melt and has high melting speed, and the CaF is not added when slagging is carried out in the converter tapping process2The cold-state casting residue, small-sized lime and steel grit aluminum deoxidizer are directly added, and the refined slag can be manufactured in advance before LF refining by utilizing the heat and impact function of the molten steel discharged from the converter, so that the molten steel heating time in the LF refining process is shortened, and the electric energy is saved;
(3) the method provided by the embodiment of the invention provides a new way for cold-state casting of the residual slag, reduces the discharge of industrial waste materials, and realizes the recycling of waste slag.
Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A method for desulfurizing molten steel during tapping of a converter is characterized by comprising the following steps:
obtaining cold-state casting residue; the chemical components of the cold-state casting slag comprise the following components in percentage by mass: 50 to 55 percent of CaO and SiO25％～10％、Al2O320 to 30 percent of MgO, 5 to 8 percent of MgO, 0.2 to 0.7 percent of S, less than or equal to 2 percent of water, less than 1 percent of FeO and MnO, and the balance of inevitable impurities;
adding molten steel into the cold-state casting residue, the small-particle lime and the deoxidizer in the tapping process to obtain deoxidized molten steel;
and after tapping is finished, increasing the flow of bottom-blown argon to stir the deoxidized molten steel to obtain desulfurized molten steel.
2. The method for desulfurizing molten steel during tapping of a converter as claimed in claim 1, wherein the cold casting residue, the small lime and the deoxidizer are added into molten steel during tapping to obtain deoxidized molten steel before tapping 1/5.
3. The method for desulfurizing molten steel during tapping of a converter as set forth in claim 1, wherein said cold-state casting residue is added in an amount of 6Kg to 8Kg per ton of steel.
4. The method for desulfurizing molten steel during tapping of a converter according to claim 1, wherein the particle size of the cold-state casting residue is 5mm to 30 mm.
5. The method for desulfurizing molten steel during tapping of a converter as set forth in claim 1, wherein the small lime is added in an amount of 2Kg to 4Kg per ton of steel.
6. The method for desulfurizing molten steel during tapping of a converter according to claim 1, wherein the deoxidizer is a steel grit aluminum deoxidizer, and the steel grit aluminum deoxidizer is used for controlling the mass percentage of dissolved aluminum in the deoxidized molten steel to be 0.03-0.05%.
7. The method for desulfurizing molten steel during tapping of a converter according to claim 1, wherein the obtaining of cold-state casting residue specifically comprises:
and cooling the hot-state casting slag after casting, and then crushing and screening to obtain cold-state casting slag.
8. The method for desulfurizing molten steel during tapping of a converter according to claim 1, wherein a slag thickness of converter slag is controlled to be less than 0.7m during the tapping.
9. The method for desulfurizing molten steel during tapping of a converter according to claim 1, wherein a flow rate of the bottom-blown argon gas is 300NL/min to 400 NL/min.
10. The method for desulfurizing molten steel during tapping of a converter according to claim 1, wherein the stirring time is 2min to 4 min.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI820759B (en) * | 2022-06-20 | 2023-11-01 | 興展技術開發股份有限公司 | Liquid steel desulfurization method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102181588A (en) * | 2011-03-22 | 2011-09-14 | 重庆中渣冶金再生资源有限公司 | Method for recycling refined casting residues during steelmaking in steel plant |
| JP2013064188A (en) * | 2011-09-20 | 2013-04-11 | Nippon Steel & Sumitomo Metal Corp | Method for recycling steelmaking slag as resource |
| CN108018402A (en) * | 2018-01-13 | 2018-05-11 | 山东钢铁股份有限公司 | A kind of low cost wash heat method |
| CN110804685A (en) * | 2019-12-05 | 2020-02-18 | 唐山瑞丰钢铁（集团）有限公司 | Slag washing and refining process for tapping of converter |
| CN112430708A (en) * | 2020-11-19 | 2021-03-02 | 广西北部湾新材料有限公司 | Recycling method of continuous casting stainless steel liquid casting residues |
| CN113201619A (en) * | 2021-05-18 | 2021-08-03 | 宝武集团鄂城钢铁有限公司 | Smelting method for improving desulfurization efficiency of converter |
-
2021
- 2021-10-18 CN CN202111209008.5A patent/CN114045376A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102181588A (en) * | 2011-03-22 | 2011-09-14 | 重庆中渣冶金再生资源有限公司 | Method for recycling refined casting residues during steelmaking in steel plant |
| JP2013064188A (en) * | 2011-09-20 | 2013-04-11 | Nippon Steel & Sumitomo Metal Corp | Method for recycling steelmaking slag as resource |
| CN108018402A (en) * | 2018-01-13 | 2018-05-11 | 山东钢铁股份有限公司 | A kind of low cost wash heat method |
| CN110804685A (en) * | 2019-12-05 | 2020-02-18 | 唐山瑞丰钢铁（集团）有限公司 | Slag washing and refining process for tapping of converter |
| CN112430708A (en) * | 2020-11-19 | 2021-03-02 | 广西北部湾新材料有限公司 | Recycling method of continuous casting stainless steel liquid casting residues |
| CN113201619A (en) * | 2021-05-18 | 2021-08-03 | 宝武集团鄂城钢铁有限公司 | Smelting method for improving desulfurization efficiency of converter |
Non-Patent Citations (1)
| Title |
|---|
| 施月循等, 东北工学院出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI820759B (en) * | 2022-06-20 | 2023-11-01 | 興展技術開發股份有限公司 | Liquid steel desulfurization method |
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