CN104818365B - Steelmaking method capable of enhancing calcium/sulfur ratio in steel - Google Patents
Steelmaking method capable of enhancing calcium/sulfur ratio in steel Download PDFInfo
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- CN104818365B CN104818365B CN201510244306.6A CN201510244306A CN104818365B CN 104818365 B CN104818365 B CN 104818365B CN 201510244306 A CN201510244306 A CN 201510244306A CN 104818365 B CN104818365 B CN 104818365B
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- slag
- calcium
- steel
- line feeding
- feeding
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 79
- 239000010959 steel Substances 0.000 title claims abstract description 79
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 title claims abstract description 50
- 229910052791 calcium Inorganic materials 0.000 title claims abstract description 45
- 239000011575 calcium Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 32
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title claims abstract description 19
- 229910052717 sulfur Inorganic materials 0.000 title claims abstract description 19
- 239000011593 sulfur Substances 0.000 title claims abstract description 19
- 238000009628 steelmaking Methods 0.000 title abstract description 3
- 230000002708 enhancing effect Effects 0.000 title abstract 3
- 239000002893 slag Substances 0.000 claims abstract description 40
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000003756 stirring Methods 0.000 claims abstract description 15
- 229910052786 argon Inorganic materials 0.000 claims abstract description 13
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 9
- 230000023556 desulfurization Effects 0.000 claims abstract description 9
- 238000010079 rubber tapping Methods 0.000 claims abstract description 8
- JGIATAMCQXIDNZ-UHFFFAOYSA-N calcium sulfide Chemical compound [Ca]=S JGIATAMCQXIDNZ-UHFFFAOYSA-N 0.000 claims description 13
- 239000003795 chemical substances by application Substances 0.000 claims description 5
- 238000007670 refining Methods 0.000 abstract description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052760 oxygen Inorganic materials 0.000 abstract description 2
- 239000001301 oxygen Substances 0.000 abstract description 2
- 238000009847 ladle furnace Methods 0.000 abstract 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 239000000463 material Substances 0.000 abstract 1
- 238000005406 washing Methods 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 14
- 238000003723 Smelting Methods 0.000 description 10
- 239000003921 oil Substances 0.000 description 9
- 239000007789 gas Substances 0.000 description 7
- 229910052742 iron Inorganic materials 0.000 description 7
- 239000000956 alloy Substances 0.000 description 6
- 229910045601 alloy Inorganic materials 0.000 description 6
- -1 desulfurization Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003818 cinder Substances 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007850 degeneration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
Classifications
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- 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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- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention relates to a steelmaking method capable of enhancing calcium/sulfur ratio in steel, which comprises the following steps: (1) in the converter tapping process, adding 200-400kg of specific-component calcium-base deoxidizing slag former into a ladle to perform slag washing on the molten steel; (2) after the LF (ladle furnace) enters the station, carrying out slag-material proportioning, and controlling the slag basicity at 4-7 and the CaO/Al2O3 ratio in the furnace slag at 1.0-1.5; (3) after making the white slag, carrying out argon stirring for further desulfurization, thereby lowering the sulfur content in the steel to 0.002% below; (4) before the LF leaves the station, feeding 100-200m of pure calcium wire by twice; and (5) after the VD (vacuum degasser) breaks air, feeding 300-600m of calcium wire by three times (100-200m each time), wherein the argon is closed in the wire feeding process. The calcium-base deoxidizing slag former is utilized to wash the molten steel so as to remove most oxygen and sulfur in the steel, and appropriate high-basicity refinery slag is prepared in the refining process. Meanwhile, the staged calcium wire feeding is adopted in the calcium treatment process to reduce the calcium loss and enhance the yield of the fed calcium wire, thereby finally achieving the goal of enhancing the calcium/sulfur ratio in steel.
Description
Technical field
The invention belongs to steelmaking technical field, particularly to a kind of method for making steel improving calcium sulfur ratio in steel.
Background technology
With the continuous development of world oil, gas industry, oil gas drilling progressively south and marine progress, drilling westwards
Reservoir depth increases, but the oil gas in many oil fields all contains h2s.For example, Sichuan Province China Luo Jia stockaded village oil well, the h in oil gas2S content
Up to h in the oil gas that branch-cut bridge gas pipeline conveys is said in 15% ~ 18%, Chuan Dong oil field2S content reaches 1%.h2It is in oil and natural gas
Most one of hazardous medium of corrosiveness, it can lead to the steel such as crude oil storage tank, oil gas pipeline to produce hydrogen induced cracking,
Have a strong impact on its service life.Research is thought, these steel grades must improve the calcium sulfur ratio in molten steel in smelting process, to suppress
The generation of hydrogen induced cracking, improves service life.
At present, iron and steel enterprise still adopts these steel grades of original technique productions.In order to improve the calcium sulfur ratio in steel, in lf essence
Producing to feeding calcium line molten steel during station, the calcium sulfur ratio in this method molten steel after feeding calcium line improves a lot really more, but
It is, the calcium content skewness in molten steel, when vd application of vacuum, the calcium in molten steel is taken out in the form of calcium steam
Walk, after vd breaks sky, in molten steel, calcium has had already decreased to very low level.Some steel production enterprise are in order to improve the calcium sulfur in steel
Than, carry out feeding calcium line and being placed on after the broken sky of vd, the calcium sulfur ratio in such molten steel has obtained large increase, but, once feed big
The calcium line of amount, not only causes the secondary oxidation of molten steel serious, and creates substantial amounts of non-metallic inclusion and remain in steel and do not have
Method removes, and so that the cleanliness factor of molten steel is deteriorated.
Chinese Patent Application No. cn201110080746.4 " anti-hic Ascalloy and its preparation technology ",
Cn200910089348.1 " method of nonmetal inclusion in a kind of anti-hic pipe line steel of control " all refers to the skill about anti-hic steel
Art, is described the technological process of production, also has and stresses to heat and rolling mill practice, but is not related to specifically to carry with regard to smelting process
Calcium sulfur ratio in high steel.
Content of the invention
The present invention is intended to provide a kind of method for making steel improving calcium sulfur ratio in steel, according to converter terminal control, wash heat, lf essence
The smelting characteristic in each period such as furnace slag making, Calcium treatment to the deoxidation of molten steel, desulfurization, slag making and Calcium treatment technique with control into
Row adjustment, to reduce the sulfur content in steel, improves the recovery rate of Calcium treatment process calcium, is finally reached the purpose improving calcium sulfur ratio.
Technical scheme: a kind of refining controlling method of calcium sulfur ratio in raising steel, its processing step includes:
(1) in ladle, in converter tapping process, add the calcio deoxidizing slag-forming agent pair of 200 ~ 400 kg special components
Molten steel carries out wash heat operation, and the sulfur content in steel is reduced to≤0.015% from 0.02% ~ 0.04%；
(2) carry out slag charge proportioning after lf stove enters the station it is ensured that basicity of slag controls 4 ~ 7, cao and al in slag2o3Ratio
Control 1.0 ~ 1.5, take a slag specimen during each lift electrode, according to the viscosity of slag, slag is adjusted, has made white slag
Time is necessary≤12 min；
(3) carry out big argon after white slag is made and stir further desulfurization, sulfur in steel is reduced to 0.002 below %；
(4) feed pure calcium line 100 ~ 200m before lf outbound at twice, feed 50 ~ 100m, line feeding time interval twice every time
>=3min, wire-feeding velocity is 150 ± 10m/min, and line feeding process closes argon, and first time line feeding is stirred to molten steel soft blow after terminating
Carry out second line feeding, second line feeding line feeding carries out soft blow to molten steel after terminating and stir until lf outbound after >=3min；
(5) vd stove feeds pure calcium line 300 ~ 600m after breaking sky in three times, every time feeding 100 ~ 200m, and line feeding interval >=
2min, wire-feeding velocity 180 ± 10m/min, line feeding process closes argon；After every time line feeding terminates, molten steel is carried out soft blow stirring >=
2min, is then shut off argon and carries out line feeding next time, third time line feeding carries out soft blow stirring operation, Zhi Daogang to molten steel after terminating
Bag outbound.
It is an advantage of the current invention that converter tapping carries out wash heat using calcio deoxidizing slag-forming agent to molten steel, big portion in removing steel
Point oxygen and sulfur, then make suitable high alkalinity refinery cinder it is ensured that steel inclusion during slag-metal reaction in refining process
Degeneration and removal are it is ensured that the effect of deoxidation, desulfurization；Meanwhile, the method using feeding calcium line stage by stage in Calcium treatment process, reduces
The loss of calcium, improves the recovery rate of feeding calcium line, is finally reached the purpose improving calcium sulfur ratio in steel.
Specific embodiment
Further illustrate present disclosure with reference to embodiment.
Embodiment one:
Converter smelting adds molten iron and steel scrap, 130 tons of molten iron, 20 tons of steel scrap, enters 1298 DEG C of stove molten iron temperature, converter smelting
Operated by normal smelting requirements, 1620 DEG C of converter terminal temperature, terminal c is 0.06 %, terminal p is 0.008 %, terminal s
For 0.036 %.Specific operation process is as follows:
(1), to 30 ton hours, the calcio deoxidizing slag-forming agent adding 360 kg special components in ladle is to molten steel for converter tapping
Carry out wash heat, be simultaneously introduced appropriate alloy and deoxidation alloying is carried out to molten steel, 100 ton hours of tapping add alloy and slag charge,
Not enough alloy is added in lf refining furnace.Ladle carries out thermometric, sampling to molten steel to after lf refine station, and in sample, sulfur content is
0.009 %；
(2), after lf stove enters the station, control 4 ~ 7 according to basicity of slag, cao and al in slag2o3Ratio control 1.0 ~
1.5 requirement carries out slag charge proportioning, and carries out making white slag operation, takes a slag specimen, according to the viscosity of slag during each lift electrode
Slag is adjusted, 10 min become white slag.
(3) and then to molten steel big argon stirring carries out further desulfurization operations, and desulfurization operations sample after terminating, sulfur in steel sample
For 0.001 8 %；
(4) before lf outbound, 100m calcium line is fed with 156m/min wire-feeding velocity, feed at a same speed again after soft blow 4min
Enter 50m calcium line, line feeding process closes argon, fed line and molten steel is carried out after soft blow stirring, ladle is hung vd stove molten steel is carried out
Application of vacuum.
(5) sample before vd application of vacuum, in sample, calcium content is 0.0017%, sulfur content is 0.0021%.Vd break sky after with
183m/min wire-feeding velocity feeds 150m calcium line, feeds 100m calcium line at a same speed again after soft blow 3min, then soft blow 3min
After continue to feed 150m calcium line at a same speed, feed calcium line terminate to carry out soft blow stirring operation to molten steel, until ladle outbound,
Steel sample is taken, the calcium content in steel sample is 0.0033%, sulfur content is 0.0009% before outbound.
Embodiment two:
Converter smelting adds molten iron and steel scrap, 128 tons of molten iron, 21 tons of steel scrap, enters 1291 DEG C of stove molten iron temperature, converter smelting
Operated by normal smelting requirements, 1626 DEG C of converter terminal temperature, terminal c is 0.06%, terminal p is 0.010%, terminal s is
0.028%.Concrete smelting operation process is as follows:
(1), to 30 ton hours, the calcio deoxidizing slag-forming agent adding 320 kg special components in ladle is to molten steel for converter tapping
Carry out wash heat, be simultaneously introduced appropriate alloy and deoxidation alloying is carried out to molten steel, 100 ton hours of tapping add alloy and slag charge,
Not enough alloy is added in lf refining furnace.Ladle carries out thermometric, sampling to molten steel to after lf refine station, and in sample, sulfur content is
0.011%；
(2), after lf stove enters the station, control 4 ~ 7 according to basicity of slag, cao and al in slag2o3Ratio control 1.0 ~
1.5 requirement carries out slag charge proportioning, and carries out making white slag operation, and 11min becomes white slag；
(3) and then to molten steel big argon stirring carries out further desulfurization operations, and desulfurization operations sample after terminating, sulfur in steel sample
For 0.002%；
(4) before lf outbound, 100m calcium line is fed with 152m/min wire-feeding velocity, feed at a same speed again after soft blow 3min
Enter 100m calcium line, after soft blow, ladle is hung vd stove and application of vacuum is carried out to molten steel；
(5) sample before vd application of vacuum, in sample, calcium content is 0.0018%, sulfur content is 0.002 3%；Vd break sky after with
185m/min wire-feeding velocity feeds 150m calcium line, feeds 100m calcium line at a same speed again after soft blow 3min, then soft blow 3min
After continue to feed 150m calcium line at a same speed, feed calcium line terminate to carry out soft blow stirring operation to molten steel, until ladle outbound,
Steel sample is taken, the calcium content in steel sample is 0.0029%, sulfur content is 0.0007% before outbound.
Claims (1)
1. a kind of method for making steel improving calcium sulfur ratio in steel, its processing step includes:
(1), in converter tapping process, add the calcio deoxidizing slag-forming agent of 200 ~ 400 kg special components that molten steel is entered in ladle
Row wash heat operates, and the sulfur content in steel is reduced to≤0.015% from 0.02% ~ 0.04%；
(2) carry out slag charge proportioning after lf stove enters the station it is ensured that basicity of slag controls 4 ~ 7, cao and al in slag2o3Ratio control
1.0 ~ 1.5, take a slag specimen during each lift electrode, according to the viscosity of slag, slag is adjusted, made the time of white slag
Necessary≤12 min；
(3) carry out big argon after white slag is made and stir further desulfurization, sulfur in steel is reduced to 0.002 below %；
(4) feed pure calcium line 100 ~ 200m before lf outbound at twice, every time feed 50 ~ 100m, twice line feeding time interval >=
3min, wire-feeding velocity be 150 ± 10m/min, line feeding process close argon, first time line feeding terminate after to molten steel soft blow stirring >=
Carry out second line feeding, second line feeding line feeding carries out soft blow to molten steel after terminating and stir until lf outbound after 3min；
(5) vd stove feeds pure calcium line 300 ~ 600m after breaking sky in three times, feeds 100 ~ 200m every time, and line feeding is spaced >=2 min, feeds
Linear velocity 180 ± 10m/min, line feeding process closes argon；Line feeding carries out soft blow stirring >=2min to molten steel, so after terminating every time
Close argon afterwards and carry out line feeding next time, third time line feeding carries out soft blow stirring operation to molten steel after terminating, until ladle outbound.
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| CN201510244306.6A CN104818365B (en) | 2015-05-14 | 2015-05-14 | Steelmaking method capable of enhancing calcium/sulfur ratio in steel |
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| CN201510244306.6A CN104818365B (en) | 2015-05-14 | 2015-05-14 | Steelmaking method capable of enhancing calcium/sulfur ratio in steel |
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| Publication Number | Publication Date |
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| CN104818365A CN104818365A (en) | 2015-08-05 |
| CN104818365B true CN104818365B (en) | 2017-01-25 |
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| CN115505679A (en) * | 2022-09-30 | 2022-12-23 | 湖南华菱湘潭钢铁有限公司 | Steelmaking method for removing residual element antimony in steel |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101921892A (en) * | 2010-09-02 | 2010-12-22 | 南京钢铁股份有限公司 | Calcium treatment method for molten steel in steelmaking |
| CN102828002A (en) * | 2012-09-25 | 2012-12-19 | 鞍钢股份有限公司 | Calcium treatment method for low-carbon low-silicon aluminum killed steel |
| CN103540833A (en) * | 2013-09-30 | 2014-01-29 | 湖南华菱湘潭钢铁有限公司 | Smelting method of HIC (Hydrogen Induced Crack)/SSCC (Sulfide Stress Corrosion Cracking)-preventing steel |
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2015
- 2015-05-14 CN CN201510244306.6A patent/CN104818365B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101921892A (en) * | 2010-09-02 | 2010-12-22 | 南京钢铁股份有限公司 | Calcium treatment method for molten steel in steelmaking |
| CN102828002A (en) * | 2012-09-25 | 2012-12-19 | 鞍钢股份有限公司 | Calcium treatment method for low-carbon low-silicon aluminum killed steel |
| CN103540833A (en) * | 2013-09-30 | 2014-01-29 | 湖南华菱湘潭钢铁有限公司 | Smelting method of HIC (Hydrogen Induced Crack)/SSCC (Sulfide Stress Corrosion Cracking)-preventing steel |
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| CN104818365A (en) | 2015-08-05 |
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Effective date of registration: 20170510 Address after: 529629 Guangdong city of Yangjiang province Yangchun Lake Town, Nanshan Industrial Zone Patentee after: YANGCHUN NEW IRON AND STEEL Co.,Ltd. Address before: 411101 Hunan Province, Xiangtan city Yuetang District Gangcheng road. Patentee before: Xiangtan Iron & Steel Co.,Ltd. Of Hunan Hualing Valin |
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