CN103627851B - Semisteel steelmaking temperature control method and semisteel steelmaking method - Google Patents
Semisteel steelmaking temperature control method and semisteel steelmaking method Download PDFInfo
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Abstract
The invention provides a semisteel steelmaking temperature control method and a semisteel steelmaking method. The method comprises the following steps: in the process of discharging semisteel into a ladle, adding 1.5-6.0kg/(t semisteel) silicon iron into the ladle, wherein the semisteel is molten steel prepared by carrying out vanadium extraction converter or dephosphorization converter blowing on vanadium-containing molten iron, and contains 3.20-3.80 wt% of C and 0.001-0.05 wt% of Si, and the temperature of the semisteel is 1320-1390 DEG C; and adding the semisteel into the steelmaking furnace, lowering an oxygen lance to perform oxygen blowing smelting while adding related slagging materials and alloys according to the blowing smelting requirements. The method can shorten the early slag formation time, enhance the steelmaking slagging speed, enhance the molten steel temperature, effectively control the steel material consumption in the steelmaking process, and avoid the problem of low utilization ratio of carbon carburizing materials.
Description
Technical field
The invention belongs to semi-steel making technical field, specifically, relate to a kind of semi-steel making temperature-controlled process and adopt the Semi-steel making method of this semi-steel making temperature-controlled process.
Background technology
Generally, by containing vanadium iron ore deposit (such as, vanadium titano-magnetite) vanadium-bearing hot metal that obtains after blast-furnace smelting is after converter extracting vanadium or dephosphorization converter are smelted, obtain half steel, the feature of this half steel is carbon low (on average about 3.6%), silicon low (less than 0.01%), manganese low (less than 0.05%), heat source insufficiency, slagging constituent content are low, and temperature comparatively molten iron is high, and slag oxidisability in early stage is lower and initial stage slagging is more difficult.When adopting this half steel to smelt, because in half steel, heating element is fewer than molten iron, in order to ensure carrying out smoothly of smelting, also needing to add temperature raising agent and supplementing heat content.In addition, the raising of molten iron temperature, can also increase adding of steel scrap amount, reduces steel making working procedure steel technology amount, thus reduces converter energy consumption.
Prior art mainly concentrates on four aspects substantially, and one is come out of the stove at half steel or add carburelant in half steel production process, to improve carbon content of molten steel, thus reduce the problem of half steel heat source insufficiency, but the carbon recovery rate of this method is lower; Two is by adding carburelant in converting process, is oxidized improves liquid steel temperature by carburelant, same, and the recovery rate of present method carbon is also low; Three is by molten steel is blown temperature raising deeply, then requires with addition of carburelant according to steel grade, and this method can cause that molten steel terminal oxygen activity is high, deoxygenated alloy consumption is large, steel technology increases; Four be blowing molten steel to requiring composition, by LF stove heating improve liquid steel temperature, this method power consumption is high, process flow lengthen.
Application number be CN93107206.9 patent document discloses a kind of method for making steel, the method uses solid iron metalloid material as the major portion of metal charge and utilizes two kinds of dissimilar carbonaceous materials and steel scrap to burn the heat of releasing.The volatilizable hydrocarbons content of one of carbonaceous material is high, its effect makes the material preheating of iron class and partial melting, hydrocarbons content that another carbonaceous material is volatilizable is low and provide reducing power for melt carburetting, and provide additional heat by burning, for strengthening the heating and melting of solid iron class material.Present method also comprises and is blown into oxygen-rich oxide gas, for the burning of hydrocarbon polymer in carbonaceous material with fusing and the melting materials capable that formed of refining.Application number be CN201110427130.X patent document discloses a kind of method for making steel and application thereof and a kind of continuous cast method, (1) uses converter to carry out just refining, then taps in ladle by just refining the molten steel obtained; (2) in tapping process, carry out carburetting and carry out selectivity deoxidation, made with the gross weight of molten steel for benchmark before carrying out alloying to molten steel, the activity oxygen level of molten steel is≤100ppm.Application number be CN200910211433.0 patent document discloses a kind of deoxidation of molten steel carburetion method and method for making steel, this method for making steel comprises taps in ladle by smelting the molten steel obtained, and in tapping process, deoxidation carburetting is carried out to molten steel, and then external refining is carried out to the molten steel obtained after deoxidation carburetting, wherein, described method of carrying out deoxidation carburetting to molten steel is deoxidation of molten steel carburetion method of the present invention.In described deoxidation carburetion method, first add carburelant, while adjustment carbon content, the oxygen in carburelant and molten steel is reacted and produce spontaneous stirring gas.The reductor added subsequently fully, equably can mix with molten steel under the stirring action of spontaneous stirring gas, thus obtains temperature, uniform composition and meet the molten steel of refining requirement, for next step operation creates good condition.Application number is the method for making steel that patent document discloses a kind of molten iron as carburant of CN02122532.X, the method is that utilization band measures and toasts, the online hot metal charging device of lagging facility, the molten iron of precalculated consumption is blended into ladle, the method for the ladle carburetting of then tapping.Application number is the method for making steel that patent document discloses a kind of carbon manganese alloy material and its preparation method and application this material of CN201010215297.5, the method adopts its carbon manganese alloy material stably to carry out carburetting to molten steel or to increase manganese, solve and smelt the problem that steel grades is unstable, qualification rate is low, the rate of recovery of carbon and manganese is high and stable, and the rate of recovery of carbon and manganese all can stably control between 90-96 % by weight.
From above-mentioned prior art, the present invention yet there are no report, still belongs to precedent.
Summary of the invention
The object of the invention is at least one item solved in the deficiency of above-mentioned prior art existence.
Such as, an object of the present invention is to solve the poor problem of steelworks semi-steel making physical temperature, and provides a kind of semi-steel making temperature-controlled process.
An aspect of of the present present invention provides a kind of semi-steel making temperature-controlled process.Said method comprising the steps of: going out in the process of half steel in ladle, the ferrosilicon of 1.5 ~ 6.0kg/ (t half steel) is joined in ladle; Then be blended in steel melting furnace by half steel, lower oxygen gun blowing is smelted and is added relevant slag making materials and alloy by blowing requirement.Wherein, described half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium or dephosphorization converter finishing blowing, and wherein contains the C of 3.20% ~ 3.80%, the Si of 0.001% ~ 0.05% by weight percentage, and the temperature of described half steel is 1320 DEG C ~ 1390 DEG C.
Another aspect provides a kind of semi-steel making temperature-controlled process.Said method comprising the steps of: after half steel is blended into steel-making converter, the ferrosilicon of 1 ~ 5kg/ (t half steel) is joined in steel-making converter; Then descend oxygen gun blowing to smelt and add relevant slag making materials and alloy by blowing requirement.
Another aspect provides a kind of semi-steel making temperature-controlled process.Said method comprising the steps of: after half steel is blended into steel-making converter, the ferrosilicon of 1 ~ 5kg/ (t half steel) joins in steel-making converter after smelting 0.5 ~ 1min by lower oxygen gun blowing, adds relevant slag making materials and alloy by blowing requirement simultaneously.
Another aspect provides a kind of Semi-steel making method.Described Semi-steel making method comprises employing semi-steel making temperature-controlled process as above to improve liquid steel temperature.
Compared with prior art, beneficial effect of the present invention comprises: can shorten initial stage slag formation time, improves steelmaking slagging speed; Liquid steel temperature can be improved; Effectively can control the consumption of steelmaking process iron and steel stock; The problem that carbonaceous carburetting material use efficiency is low can be avoided.
Embodiment
Hereinafter, semi-steel making temperature-controlled process of the present invention and Semi-steel making method will be described in detail in conjunction with exemplary embodiment.
In one exemplary embodiment of the present invention, semi-steel making temperature-controlled process can comprise the following steps: going out in the process of half steel in ladle, the ferrosilicon of 1.5 ~ 6.0kg/ (t half steel) is joined in ladle, wherein, described half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium or dephosphorization converter finishing blowing, and wherein containing the C of 3.20% ~ 3.80%, the Si of 0.001% ~ 0.05% by weight percentage, the temperature of described half steel is 1320 DEG C ~ 1390 DEG C; Then be blended in steel melting furnace by half steel, lower oxygen gun blowing is smelted and is added relevant slag making materials and alloy by blowing requirement.Preferably, in the method for this exemplary embodiment, the add-on of ferrosilicon can be the ferrosilicon of 2.2 ~ 4.5kg/ (t half steel).
In another exemplary embodiment of the present invention, semi-steel making temperature-controlled process can comprise the following steps: after half steel is blended into steel-making converter, joins in steel-making converter by the ferrosilicon of 1 ~ 5kg/ (t half steel); Then descend oxygen gun blowing to smelt and add relevant slag making materials and alloy by blowing requirement.
In another exemplary embodiment of the present invention, semi-steel making temperature-controlled process can comprise the following steps: after half steel is blended into steel-making converter, after lower oxygen gun blowing smelts 0.5 ~ 1min, the ferrosilicon of 1 ~ 5kg/ (t half steel) is joined in steel-making converter, adds relevant slag making materials and alloy by blowing requirement simultaneously.
In superincumbent exemplary embodiment, the temperature of half steel can be 1320 DEG C ~ 1380 DEG C, and the add-on of ferrosilicon can be determined according to half steel temperature, and half steel temperature more low-silicon iron add-on is also fewer.
In semi-steel making temperature-controlled process of the present invention, relevant slag making materials can be lime, high magnesium lime, composite fluxing medium, wherein, containing SiO in composite fluxing medium
216% ~ 20%, the CaO of Mn10% ~ 15% and surplus.The add-on of relevant slag making materials can add according to steel-making requirements.Described alloy is steel-making alloys in common use, and its add-on can add according to smelting requirements.In semi-steel making temperature-controlled process of the present invention, ferrosilicon can contain the Si of by weight percentage more than 75%.
In another exemplary embodiment of the present invention, Semi-steel making method comprises employing semi-steel making temperature-controlled process as above to improve liquid steel temperature.
Below in conjunction with the description exemplary embodiment of the present invention of concrete illustrating property of example.
Example 1
In this example, half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium finishing blowing, and wherein contains the C of 3.52%, the Si of 0.01% by weight percentage.
Going out in the process of half steel in ladle, the ferrosilicon of 1.5kg/ (t half steel) is being joined in ladle; Then half steel is blended in steel melting furnace, lower oxygen gun blowing is smelted and is added the lime of 35kg/ (t half steel), 15kg/ (t half steel) high magnesium lime, 1kg/ (t half steel) composite fluxing medium, initial stage slag formation time 2.2min, after liquid steel temperature reaches 1650 DEG C, propose oxygen rifle, stop blowing.The carbon content obtaining molten steel is 0.11%, and ton steel steel technology is 1050kg.
Example 2
In this example, half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium finishing blowing, and wherein contains the C of 3.47%, the Si of 0.01% by weight percentage.
Going out in the process of half steel in ladle, the ferrosilicon of 6kg/ (t half steel) is being joined in ladle; Then half steel is blended in steel melting furnace, lower oxygen gun blowing is smelted and is added the lime of 36kg/ (t half steel), 10kg/ (t half steel) high magnesium lime, and initial stage slag formation time 2.6min, after liquid steel temperature reaches 1680 DEG C, propose oxygen rifle, stop blowing.The carbon content obtaining molten steel is 0.19%, and ton steel steel technology is 1051kg.
Example 3
In this example, half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium finishing blowing, and wherein contains the C of 3.55%, the Si of 0.02% by weight percentage.
After half steel is blended into steel-making converter, the ferrosilicon of 1.5kg/ (t half steel) is joined in steel-making converter; Then descend oxygen gun blowing to smelt and add lime, 13kg/ (t half steel) high magnesium lime of 32kg/ (t half steel), initial stage slag formation time 3.1min, after liquid steel temperature reaches 1670 DEG C, proposing oxygen rifle, stop blowing.The carbon content obtaining molten steel is 0.16%, and ton steel steel technology is 1049kg.
Example 4
In this example, half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium finishing blowing, and wherein contains the C of 3.72%, the Si of 0.03% by weight percentage.
After half steel is blended into steel-making converter, the ferrosilicon of 6kg/ (t half steel) is joined in steel-making converter; Then descend oxygen gun blowing to smelt and add lime, 16kg/ (t half steel) high magnesium lime of 41kg/ (t half steel), initial stage slag formation time 3.5min, after liquid steel temperature reaches 1675 DEG C, proposing oxygen rifle, stop blowing.The carbon content obtaining molten steel is 0.20%, and ton steel steel technology is 1053kg.
Example 5
In this example, half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium finishing blowing, and wherein contains the C of 3.55%, the Si of 0.02% by weight percentage.
After half steel is blended into steel-making converter, the ferrosilicon of 1.5kg/ (t half steel) joins in steel-making converter after smelting 1min by lower oxygen gun blowing; Add the lime of 38kg/ (t half steel), 12kg/ (t half steel) high magnesium lime, initial stage slag formation time 2.5min simultaneously, re-blow after reaching 1665 DEG C to liquid steel temperature after catch carbon, propose oxygen rifle, stop blowing.The carbon content obtaining molten steel is 0.11%, and ton steel steel technology is 1048kg.
Example 6
In this example, half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium finishing blowing, and wherein contains the C of 3.45%, the Si of 0.01% by weight percentage.
After half steel is blended into steel-making converter, the ferrosilicon of 6kg/ (t half steel) joins in steel-making converter after smelting 1min by lower oxygen gun blowing; Add the lime of 37kg/ (t half steel), 13kg/ (t half steel) high magnesium lime, initial stage slag formation time 3min simultaneously, re-blow after reaching 1650 DEG C to liquid steel temperature after catch carbon, propose oxygen rifle, stop blowing.The carbon content obtaining molten steel is 0.018%, and ton steel steel technology is 1049kg.
The present invention effectively can solve the poor problem of steelworks semi-steel making physical temperature; The heat-transmission of steelmaking process elemental oxygen can be increased, liquid steel temperature is controlled in claimed range, reduce the oxidation of carbon and iron in steel simultaneously, reduce steel technology, improve semi-steel making because slagging element is few the problem of slag making difficulty; In the quick formation better promoting steelmaking slag, converter control liquid steel temperature and endpoint carbon content can be conducive to, be conducive to improving semi-steel making level of control.
Although describe the present invention in conjunction with exemplary embodiment above, those of ordinary skill in the art should be clear, when not departing from the spirit and scope of claim, can carry out various amendment to above-described embodiment.
Claims (5)
1. a semi-steel making temperature-controlled process, is characterized in that, said method comprising the steps of:
Going out in the process of half steel in ladle, the ferrosilicon of 1.5 ~ 6.0kg/ (t half steel) is joined in ladle, wherein, described half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium or dephosphorization converter finishing blowing, and wherein containing the C of 3.20% ~ 3.80%, the Si of 0.001% ~ 0.05% by weight percentage, the temperature of described half steel is 1320 DEG C ~ 1390 DEG C;
Then be blended in steel melting furnace by half steel, lower oxygen gun blowing is smelted and is added relevant slag making materials and alloy by blowing requirement, and wherein, described relevant slag making materials is lime, high magnesium lime, composite fluxing medium, containing SiO in composite fluxing medium
216% ~ 20%, the CaO of Mn 10% ~ 15% and surplus.
2. a semi-steel making temperature-controlled process, is characterized in that, said method comprising the steps of:
After half steel is blended into steel-making converter, the ferrosilicon of 1 ~ 5kg/ (t half steel) is joined in steel-making converter, wherein, described half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium or dephosphorization converter finishing blowing, and wherein containing the C of 3.20% ~ 3.80%, the Si of 0.001% ~ 0.05% by weight percentage, the temperature of described half steel is 1320 DEG C ~ 1390 DEG C;
Then descend oxygen gun blowing to smelt and add relevant slag making materials and alloy by blowing requirement, wherein, described relevant slag making materials is lime, high magnesium lime, composite fluxing medium, containing SiO in composite fluxing medium
216% ~ 20%, the CaO of Mn 10% ~ 15% and surplus.
3. a semi-steel making temperature-controlled process, is characterized in that, said method comprising the steps of:
After half steel is blended into steel-making converter, after lower oxygen gun blowing smelts 0.5 ~ 1min, the ferrosilicon of 1 ~ 5kg/ (t half steel) is joined in steel-making converter, add relevant slag making materials and alloy by blowing requirement simultaneously, wherein, described half steel is the molten steel of vanadium-bearing hot metal after converter extracting vanadium or dephosphorization converter finishing blowing, and wherein contain the C of by weight percentage 3.20% ~ 3.80%, the Si of 0.001% ~ 0.05%, the temperature of described half steel is 1320 DEG C ~ 1390 DEG C, wherein, described relevant slag making materials is lime, high magnesium lime, composite fluxing medium, containing SiO in composite fluxing medium
216% ~ 20%, the CaO of Mn 10% ~ 15% and surplus.
4. semi-steel making temperature-controlled process as claimed in any of claims 1 to 3, is characterized in that, the add-on of described ferrosilicon is the ferrosilicon of 2.5 ~ 4.5kg/ (t half steel).
5. a Semi-steel making method, is characterized in that, described Semi-steel making method comprises employing semi-steel making temperature-controlled process as claimed in any of claims 1 to 3 to improve liquid steel temperature.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104004882B (en) * | 2014-06-04 | 2016-03-23 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of half steel increases the method for silicon process and the method for semisteel converter steelmaking |
| CN104017936A (en) * | 2014-06-10 | 2014-09-03 | 张家港市锦丰润尔发五金塑料厂 | Oxide steel-making method |
| CN107058679B (en) * | 2017-04-18 | 2019-03-19 | 攀钢集团攀枝花钢铁研究院有限公司 | A method of stablizing half steel quality |
| CN109097524A (en) * | 2018-09-30 | 2018-12-28 | 四川德胜集团钒钛有限公司 | A kind of method that vanadium extraction semisteel smelting reduces molten steel consumption |
| CN112646943A (en) * | 2020-12-17 | 2021-04-13 | 攀钢集团西昌钢钒有限公司 | Method for controlling dry dedusting explosion venting in semisteel smelting |
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| CN102766722A (en) * | 2012-07-17 | 2012-11-07 | 攀钢集团研究院有限公司 | Method for smelting high-carbon steel from semi-steel |
| CN103205524A (en) * | 2013-04-15 | 2013-07-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for smelting low-sulfur steel from semi-steel |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102766722A (en) * | 2012-07-17 | 2012-11-07 | 攀钢集团研究院有限公司 | Method for smelting high-carbon steel from semi-steel |
| CN103205524A (en) * | 2013-04-15 | 2013-07-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for smelting low-sulfur steel from semi-steel |
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