CN103255264A - Method for dephosphorizing by using LF refining furnace - Google Patents
Method for dephosphorizing by using LF refining furnace Download PDFInfo
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- CN103255264A CN103255264A CN2013102273649A CN201310227364A CN103255264A CN 103255264 A CN103255264 A CN 103255264A CN 2013102273649 A CN2013102273649 A CN 2013102273649A CN 201310227364 A CN201310227364 A CN 201310227364A CN 103255264 A CN103255264 A CN 103255264A
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- Prior art keywords
- temperature
- dephosphorization
- steel
- molten steel
- station
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- 238000007670 refining Methods 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 10
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims abstract description 62
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 54
- 239000010959 steel Substances 0.000 claims abstract description 54
- 229910052786 argon Inorganic materials 0.000 claims abstract description 31
- 239000002893 slag Substances 0.000 claims abstract description 19
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 17
- 239000011574 phosphorus Substances 0.000 claims abstract description 17
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims abstract description 15
- 235000011941 Tilia x europaea Nutrition 0.000 claims abstract description 15
- 239000004571 lime Substances 0.000 claims abstract description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 8
- 239000001301 oxygen Substances 0.000 claims abstract description 8
- 238000007664 blowing Methods 0.000 claims description 19
- 238000003756 stirring Methods 0.000 claims description 12
- 238000005070 sampling Methods 0.000 claims description 11
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 claims description 7
- 239000010436 fluorite Substances 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 4
- 229910004261 CaF 2 Inorganic materials 0.000 claims description 3
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 229910052717 sulfur Inorganic materials 0.000 claims description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 238000009847 ladle furnace Methods 0.000 abstract 3
- 239000002245 particle Substances 0.000 abstract 2
- 230000001590 oxidative effect Effects 0.000 abstract 1
- 239000008187 granular material Substances 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 206010058490 Hyperoxia Diseases 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000000222 hyperoxic effect Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- DPTATFGPDCLUTF-UHFFFAOYSA-N phosphanylidyneiron Chemical compound [Fe]#P DPTATFGPDCLUTF-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention relates to the field of secondary refining of LF (ladle furnace) refining furnaces, in particular to a method for dephosphorizing by using an LF refining furnace, which is characterized in that the oxidizing property of molten steel is used for controlling the incoming oxygen content and the adding amount of lime particles and refining slag, so that the incoming temperature of the molten steel is reduced to meet the low-temperature condition required by dephosphorization. Compared with the prior art, the invention has the beneficial effects that: 1) according to the high-oxidizability characteristic of molten steel, lime particles are added to provide high alkalinity required by dephosphorization, about 1 ton of slag is added to meet the requirement of large slag amount required by dephosphorization, the station entering temperature of the molten steel is generally 1600-1620 ℃, and the low-temperature condition required by dephosphorization is met. 2) When the content of phosphorus in the argon station is between 0.010 and 0.015 percent, dephosphorization is carried out by adopting one-time feeding, and the dephosphorization rate reaches 40 to 45 percent; when the content of phosphorus in the argon station is more than 0.015%, dephosphorization is carried out through secondary feeding, the dephosphorization rate is 46-51%, the content of finished phosphorus is controlled within 0.010%, and quality risks are avoided.
Description
Technical field
The present invention relates to LF refining furnace secondary refining field, relate in particular to a kind of method of the LF of utilization refining furnace dephosphorization.
Background technology
Steelworks is produced the IF steel and is generally adopted hot metal pretreatment-converter-vacuum-continuous casting process, produces by " IF steel Operating Guideline ".But some steel grades are arranged, for example require phosphorus content less than 0.010% in the M3A33 steel grade, converter is because molten iron phosphorus is high or the change slag is bad, argon station phosphorus is often greater than 0.010%, and vacuum oven does not possess dephosphorizing capacity, and quality product can't be guaranteed, if phosphorus content exceed standard can only steel grade degradation or change steel.
Summary of the invention
The method that the purpose of this invention is to provide a kind of LF of utilization refining furnace dephosphorization is avoided because the phosphorus height causes the steel grade degradation or changes steel, and the control quality risk guarantees quality product.
For achieving the above object, technical scheme of the present invention is:
A kind of method of utilizing LF refining furnace dephosphorization, the enter the station add-on of oxygen level and lime grain and refining slag of the oxidisability of utilizing molten steel itself to have, control reduces the molten steel inlet temperature and satisfies the required cold condition of dephosphorization, when argon station phosphorus greater than 0.015% the time, its concrete operations step is as follows:
1) control the molten steel oxygen level 500～700ppm that enters the station, liquid steel temperature is 1600～1620 ℃, adds 3.2 ~ 3.5kg/t steel lime grain in the first batch, 0.8 ~ 1.0kg/t steel refining slag and 0.12 ~ 0.15kg/t steel fluorite;
2) argon blowing rate is adjusted into 20 ~ 25Nm
3/ h is controlled to be 4 ~ 4.5 ℃/minute with the electrode temperature rise rate, and by taking out of the temperature control heating-up time, heating-up time and inlet temperature relation see Table 1 according to inlet temperature;
Table 1
| Inlet temperature (℃) | <1600 | 1600～1610 | 1610～1620 | 1620～1630 | >1630 |
| Heating-up time (min) | 10 | 8 | 7 | 6 | 4 |
3) begin to carry out the secondary charging dephosphorization in 3 ~ 4 minutes in intensification, add lime grain 2 ~ 2.2kg/t steel;
4) after intensification finished, the adjustment argon blowing rate was 95 ~ 100Nm
3/ h stirs 3 ~ 5min, thermometric, and when temperature during greater than 1630 ℃, sampling is taken out of; When temperature during less than 1630 ℃, carry out secondary temperature elevation for 1640 ℃ by taking out of temperature, 4 ~ 5 ℃/minute of temperature rise rates, after secondary temperature elevation finished, argon blowing rate was adjusted into 95 ~ 100Nm
3/ h stirs 3 ~ 5min, and sampling is taken out of.
When argon station phosphorus was between 0.010 ~ 0.015%, its concrete operations step was as follows:
1) control the molten steel oxygen level 500～700ppm that enters the station, liquid steel temperature is 1600～1620 ℃, adds 3.6 ~ 3.8kg/t steel lime grain, 0.8 ~ 1.0kg/t steel refining slag and 0.12 ~ 0.15kg/t steel fluorite;
2) argon blowing rate is adjusted into 20 ~ 25Nm
3/ h is controlled to be 4 ~ 4.5 ℃/minute with the electrode temperature rise rate, and by taking out of the temperature control heating-up time, heating-up time and inlet temperature relation see Table 2 according to inlet temperature;
Table 2
| Inlet temperature (℃) | <1600 | 1600～1610 | 1610～1620 | 1620～1630 | >1630 |
| Heating-up time (min) | 10 | 9 | 8 | 7 | 5 |
3) after intensification finished, the adjustment argon blowing rate was 95 ~ 100Nm
3/ h stirs 3 ~ 5min, thermometric, and when temperature during greater than 1630 ℃, sampling is taken out of; When temperature during less than 1630 ℃, carry out secondary temperature elevation for 1640 ℃ by taking out of temperature, 4 ~ 5 ℃/minute of temperature rise rates, after secondary temperature elevation finished, argon blowing rate was adjusted into 95 ~ 100Nm
3/ h stirs 3 ~ 5min, and sampling is taken out of.
The composition of described refining slag is by weight percentage: Al
2O
335 ~ 46%, SiO
2≤ 8%, S≤0.05%, Fe
2O
3≤ 1.5%, MgO≤6%, CaO 〉=35%, CaF
2≤ 5%, H
2O≤0.5%, 1300 ~ 1400 ℃ of fusing points.
Compared with prior art, the invention has the beneficial effects as follows: the hyperoxia voltinism characteristics of 1) utilizing molten steel itself, adding the lime grain provides dephosphorization required high basicity, the quantity of slag that adds about 1 ton, satisfied the required big quantity of slag of dephosphorization, the molten steel inlet temperature is generally 1600～1620 ℃, has satisfied the required cold condition of dephosphorization.2) when argon station phosphorus is between 0.010 ~ 0.015%, adopt once reinforced dephosphorization, dephosphorization rate reaches 40～45%; Argon station phosphorus was greater than 0.015% o'clock, and by the secondary charging dephosphorization, dephosphorization rate 46～51% makes the control of finished product phosphorus in 0.010%, has stopped quality risk fully.
Embodiment
The invention will be further described below in conjunction with specific embodiment:
Embodiment 1
Be example with steel grade M3A33,250 tons of LF refining furnace heat sizes, steel grade requires P≤0.010%, if argon station phosphorus is 0.014% to exceed the steel grade requirement, then molten steel is moved to the LF stove, advance 1610 ℃ of LF stove thermometrics, add 900kg lime granule, 250kg refining slag and 30kg fluorite are adjusted into 25Nm with argon blowing rate
3/ h is made as 4 ℃/minute with the electrode temperature rise rate, is that the concrete heating-up time value of 9min(is chosen by table 2 according to inlet temperature by taking out of 1635 ℃ of control heating-up times of temperature), heat up after the end, argon blowing rate is adjusted into 95Nm
3/ h stirs 3min, thermometric, and temperature is greater than 1630 ℃, and sampling is taken out of.
Embodiment 2
Be example with steel grade CSC, 250 tons of LF refining furnace heat sizes, steel grade requires P≤0.010%, if argon station phosphorus 0.016% exceeds the steel grade requirement, then molten steel is moved to the LF stove, advance 1620 ℃ of LF stove thermometrics, add 825kg lime granule, 225kg refining slag and 37.5kg fluorite are adjusted into 20Nm with argon blowing rate
3/ h is made as 4.5 ℃/minute with the electrode temperature rise rate, is that the concrete heating-up time value of 7min(is chosen by table 1 according to inlet temperature by taking out of 1635 ℃ of control heating-up times of temperature), heat up after the end, argon blowing rate is adjusted into 95Nm
3/ h stirs 3min, thermometric, and temperature is greater than 1630 ℃, and sampling is taken out of.
Embodiment 3
Be example with steel grade M3A33,250 tons of LF refining furnace heat sizes, steel grade requires P≤0.010%, if argon station phosphorus 0.018% exceeds the steel grade requirement, then molten steel is moved to the LF stove, advance 1610 ℃ of LF stove thermometrics, add 800kg lime granule, 200kg refining slag and 35kg fluorite are adjusted into 25Nm with argon blowing rate
3/ h is made as 4 ℃/minute with the electrode temperature rise rate, is that the concrete heating-up time value of 8min(is chosen by table 1 according to inlet temperature by taking out of 1635 ℃ of control heating-up times of temperature), heat up after the end, argon blowing rate is adjusted into 100Nm
3/ h stirs 5min, thermometric, and temperature is then controlled the secondary temperature elevation times for 1640 ℃ by taking out of temperature less than 1630 ℃, 5 ℃/minute of temperature rise rates, after secondary temperature elevation finished, argon blowing rate was adjusted into 100Nm
3/ h stirs 5min, and sampling is taken out of.
In above-described embodiment, the composition of refining slag is by weight percentage: Al
2O
335 ~ 46%, SiO
2≤ 8%, S≤0.05%, Fe
2O
3≤ 1.5%, MgO≤6%, CaO 〉=35%, CaF
2≤ 5%, H
2O≤0.5%, 1300 ~ 1400 ℃ of fusing points.
Claims (3)
1. method of utilizing LF refining furnace dephosphorization, it is characterized in that, the oxidisability of utilizing molten steel itself to have, control the add-on of enter the station oxygen level and lime grain and refining slag, reduce the molten steel inlet temperature and satisfy the required cold condition of dephosphorization, when argon station phosphorus greater than 0.015% the time, its concrete operations step is as follows:
1) control the molten steel oxygen level 500～700ppm that enters the station, liquid steel temperature is 1600～1620 ℃, adds 3.2 ~ 3.5kg/t steel lime grain in the first batch, 0.8 ~ 1.0kg/t steel refining slag and 0.12 ~ 0.15kg/t steel fluorite;
2) argon blowing rate is adjusted into 20 ~ 25Nm
3/ h is controlled to be 4 ~ 4.5 ℃/minute with the electrode temperature rise rate, and by taking out of the temperature control heating-up time, heating-up time and inlet temperature relation see Table 1 according to inlet temperature;
Table 1
3) begin to carry out the secondary charging dephosphorization in 3 ~ 4 minutes in intensification, add lime grain 2 ~ 2.2kg/t steel;
4) after intensification finished, the adjustment argon blowing rate was 95 ~ 100Nm
3/ h stirs 3 ~ 5min, thermometric, and when temperature during greater than 1630 ℃, sampling is taken out of; When temperature during less than 1630 ℃, carry out secondary temperature elevation for 1640 ℃ by taking out of temperature, 4 ~ 5 ℃/minute of temperature rise rates, after secondary temperature elevation finished, argon blowing rate was adjusted into 95 ~ 100Nm
3/ h stirs 3 ~ 5min, and sampling is taken out of.
2. method of utilizing LF refining furnace dephosphorization, it is characterized in that, the oxidisability of utilizing molten steel itself to have, control the add-on of enter the station oxygen level and lime grain and refining slag, reduce the molten steel inlet temperature and satisfy the required cold condition of dephosphorization, when argon station phosphorus was between 0.010 ~ 0.015%, its concrete operations step was as follows:
1) control the molten steel oxygen level 500～700ppm that enters the station, liquid steel temperature is 1600～1620 ℃, adds 3.6 ~ 3.8kg/t steel lime grain, 0.8 ~ 1.0kg/t steel refining slag and 0.12 ~ 0.15kg/t steel fluorite;
2) argon blowing rate is adjusted into 20 ~ 25Nm
3/ h is controlled to be 4 ~ 4.5 ℃/minute with the electrode temperature rise rate, and by taking out of the temperature control heating-up time, heating-up time and inlet temperature relation see Table 2 according to inlet temperature;
Table 2
3) after intensification finished, the adjustment argon blowing rate was 95 ~ 100Nm
3/ h stirs 3 ~ 5min, thermometric, and when temperature during greater than 1630 ℃, sampling is taken out of; When temperature during less than 1630 ℃, carry out secondary temperature elevation for 1640 ℃ by taking out of temperature, 4 ~ 5 ℃/minute of temperature rise rates, after secondary temperature elevation finished, argon blowing rate was adjusted into 95 ~ 100Nm
3/ h stirs 3 ~ 5min, and sampling is taken out of.
3. a kind of method of utilizing LF refining furnace dephosphorization according to claim 1 and 2 is characterized in that the composition of described refining slag is by weight percentage: Al
2O
335 ~ 46%, SiO
2≤ 8%, S≤0.05%, Fe
2O
3≤ 1.5%, MgO≤6%, CaO 〉=35%, CaF
2≤ 5%, H
2O≤0.5%, 1300 ~ 1400 ℃ of fusing points.
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| CN2013102273649A CN103255264A (en) | 2013-06-07 | 2013-06-07 | Method for dephosphorizing by using LF refining furnace |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105039647A (en) * | 2015-06-23 | 2015-11-11 | 武汉钢铁(集团)公司 | LF furnace shallow dephosphorization refining method |
| CN103468868B (en) * | 2013-08-29 | 2017-07-21 | 鞍钢股份有限公司 | Method for improving cleanliness of low-phosphorus interstitial-free steel |
| CN107012293A (en) * | 2016-01-27 | 2017-08-04 | 鞍钢股份有限公司 | Method for improving LF furnace temperature rise efficiency and reducing solvent consumption |
| CN113832295A (en) * | 2021-09-17 | 2021-12-24 | 北京首钢股份有限公司 | Dephosphorization method for emergency remediation |
| CN115061522A (en) * | 2022-05-25 | 2022-09-16 | 广东韶钢松山股份有限公司 | LF temperature control method |
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| CN101319265A (en) * | 2008-07-17 | 2008-12-10 | 鞍钢股份有限公司 | Powder additive for external refining desulfurization and removing fine foreign matter and its preparation method |
| CN102296148A (en) * | 2010-06-25 | 2011-12-28 | 鞍钢股份有限公司 | Dephosphorization method in IF steel ladle |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103468868B (en) * | 2013-08-29 | 2017-07-21 | 鞍钢股份有限公司 | Method for improving cleanliness of low-phosphorus interstitial-free steel |
| CN105039647A (en) * | 2015-06-23 | 2015-11-11 | 武汉钢铁(集团)公司 | LF furnace shallow dephosphorization refining method |
| CN107012293A (en) * | 2016-01-27 | 2017-08-04 | 鞍钢股份有限公司 | Method for improving LF furnace temperature rise efficiency and reducing solvent consumption |
| CN113832295A (en) * | 2021-09-17 | 2021-12-24 | 北京首钢股份有限公司 | Dephosphorization method for emergency remediation |
| CN115061522A (en) * | 2022-05-25 | 2022-09-16 | 广东韶钢松山股份有限公司 | LF temperature control method |
| CN115061522B (en) * | 2022-05-25 | 2024-04-02 | 广东韶钢松山股份有限公司 | LF temperature control method |
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