CN103205524B - Method for smelting low-sulfur steel from semi-steel - Google Patents
Method for smelting low-sulfur steel from semi-steel Download PDFInfo
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Abstract
The invention provides a method for smelting low-sulfur steel from semi-steel. The method comprises the following steps of: guiding liquid iron into a vanadium extracting converter for blowing so as to form semi-steel; tapping the semi-steel to a steel ladle and adding silicon-iron alloy to the steel ladle in the semi-steel tapping process so as to increase the content of silicon in liquid steel; guiding the liquid steel into the converter and adding a slagging material to the converter for smelting; discharging sulfur enriched slag in the converter, adding high-magnesium lime to the steel ladle by an quantity of 5-7 Kg/t of steel to blend with the liquid steel in the process of tapping steel to the steel ladle, and adding a slag regulating agent to the slag surface of the steel ladle after steel tapping is finished; performing argon refining on the liquid steel; performing desulfurization refining on the liquid steel in a steel ladle refining furnace; performing calcium treatment on the liquid steel in such a manner of feeding a calcium alloy line to the liquid steel; and performing liquid steel casting through a continuous casting process and obtaining a casting blank having the sulfur content not higher than 0.010wt%. With the method provided by the invention, the problems of iron loss caused by desulfurization drossing, insufficient semi-steel smelting heat source and the like in smelting of low-sulfur steel from semi-steel are effectively solved; and the desulfurization effect is excellent.
Description
Technical field
The present invention relates to steelmaking technical field, more particularly, relate to a kind of method adopting semi-steel after extraction of vanadium smelting low-sulfur steel.
Background technology
Concerning most of steel grade, sulphur is harmful element, steel can be made to produce hot-short, also can form the mechanical property of sulfide inclusion to steel and have a negative impact.Therefore, reducing sulphur content in molten steel is the vital task of STEELMAKING PRODUCTION.
Traditional molten iron smelting low-sulfur steel technical process is mainly: desulfurizing iron → skim → converter → LF(RH) refining → continuous casting; And when using v-ti magnetite ore resources to smelt, the main raw material of converter steelmaking is through the half steel after special vanadium extraction by converter blowing, adopts the technical process of semisteel smelting low-sulfur steel to be mainly: desulfurizing iron → skim → vanadium extraction → converter smelting → LF(RH) refining → continuous casting.Molten steel sulfur content after blast-furnace smelting is generally between 0.04wt% ~ 0.08wt%, but due to containing the element such as vanadium, titanium, molten iron viscosity is large, and because of containing the oxide compound such as vanadium, titanium in molten iron slag, molten iron slag viscosity is also large, when this causes pretreatment desulfurizing, sorbent consumption is large, desulfurization slag difficulty is separated with molten iron, when skimming, in slag, all iron content is high, and iron loss is comparatively large, and steel-making cost is high.Simultaneously, in the half steel that vanadium-bearing hot metal obtains after desulfurization vanadium extraction, carbon mass percentage is 3.4% ~ 4.0%, in half steel, silicon, manganese heating slagging constituent content are vestige, therefore, semi-steel making has in converting process that acid slagging material is few, slag system constituent element is single and the features such as shortage of heat, form initial stage slag required time under causing semi-steel making condition long, dephosphorization, desulfurization degree are low.Visible, compared with common molten iron-steelmaking, employing semisteel smelting low-sulfur steel is more difficult, iron loss is larger, and smelting cost is higher.
Publication number is that the Chinese patent application of CN102605239A discloses a kind of low-sulfur steel and production method thereof, and its technical process is: hot metal pretreatment → combined blown converter smelting → converter tapping wash heat → refining → Ca process → sheet billet continuous casting → hot rolling.Finished product molten steel sulphur content can be controlled within 0.002% by this technical process.In this patent, first the production of low-sulfur steel need carry out hot metal pretreatment and take out desulfurization slag, and process of skimming iron loss is larger, and production cost is higher; Secondly, do not tell about the concrete measure controlling converter smelting and refining process sulphur content in detail, and the method is applicable to common molten steel, and for being described whether being applicable to half steel.
Summary of the invention
For the deficiencies in the prior art, an object of the present invention is to solve in above-mentioned prior art the one or more problems existed.The invention provides a kind of method of semisteel smelting low-sulfur steel, use the present invention can effectively solve semisteel smelting heat source insufficiency, the problem that desulphurization and slag skimming iron loss is large, sweetening effectiveness is good, simple to operate, and cost is low.
To achieve these goals, the invention provides a kind of method of semisteel smelting low-sulfur steel.Said method comprising the steps of: directly molten iron is blended into converter extracting vanadium and carries out blowing to form half steel; Half steel is tapped in ladle, and going out in half steel process to add ferro-silicon in ladle to increase the silicone content in molten steel; Molten steel is blended into converter, then in converter, adds slag making materials and smelt; Outwell the rich sulphur slag in Converter, the high magnesium lime adding 5 ~ 7Kg/t steel to ladle in tapping to the process of ladle mixes with molten steel and rushes, and on the ladle top of the slag, adds slag supplying agent after tapping terminates; Ar blowing refining is carried out to molten steel; Molten steel is carried out desulfurizing and refining at ladle refining furnace; In the mode of feeding calcium alloy line to molten steel, Calcium treatment is carried out to molten steel; Continuous casting process is adopted to carry out pouring molten steel and obtain sulphur content not higher than the strand of 0.010wt%.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, in described step of being tapped in ladle by half steel, when reaching 1/3 of converter extracting vanadium molten steel total amount in tap, in ladle, add ferro-silicon.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, can contain the silicon of 70 ~ 85wt% in described ferro-silicon, its add-on is 2 ~ 4Kg/t steel.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, described slag making materials can comprise the slag former of the quickened lime of 50 ~ 65Kg/t steel, the high magnesium lime of 25 ~ 30Kg/t steel and 15 ~ 25Kg/t steel.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, after outwelling the step of rich sulphur slag in stove described in described method can also be included in, before converter tapping, the high magnesium lime adding 3 ~ 5Kg/t steel in converter carries out dry slag, to reduce lower quantity of slag during tapping.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, the add-on of described slag supplying agent can be 3 ~ 5Kg/t steel, and described slag supplying agent can comprise the Al of 15 ~ 25% by weight percentage
2o
3, the CaO of 35 ~ 45%, the SiO of 5 ~ 15%
2, 10 ~ 15% metal A l, and the inevitable impurity of surplus.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, described Argon intensity of carrying out in ar blowing refining step molten steel can be 0.003 ~ 0.005m
3/ (mint steel), and argon blowing time can be 5 ~ 8 minutes.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, described molten steel to be carried out at ladle refining furnace in the step of desulfurizing and refining, can add the whipping agent of the quickened lime of 2.5 ~ 5Kg/t steel, the fluorite of 0.5 ~ 1Kg/t steel, the aluminum shot of 0.3 ~ 0.6Kg/t steel and 5 ~ 6Kg/t steel in ladle after, start to add heat refining for the first time; Wherein, the composition of described whipping agent can contain CaO:45 ~ 60%, CaF by weight percentage
2: 5 ~ 10%, burning decrement: 25 ~ 35%, gas forming amount is not less than 45L/Kg; Add in described first time in the process of heat refining and adopt the first bottom blowing gas intensity to stir, described first bottom blowing gas intensity is 0.003 ~ 0.005m
3/ (mint
steel), stop heating after adding heat refining 12 ~ 15min, and improve air supply intensity to the second bottom blowing gas intensity stirring 3 ~ 5min, described second bottom blowing gas intensity is 0.005 ~ 0.01m
3/ (mint
steel); The aluminum shot adding the quickened lime of 2 ~ 4Kg/t steel, the fluorite of 0.5 ~ 0.8Kg/t steel and 0.3 ~ 0.5Kg/t steel again in ladle carries out second time and adds heat refining, add in described second time in the process of heat refining and adopt described first bottom blowing gas intensity to stir, after refining 8 ~ 10min, stop heating; Then, refining is terminated after adopting described second air supply intensity to stir 3 ~ 5min.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, described can comprise to the mode of molten steel hello calcium alloy line the step that molten steel carries out Calcium treatment: with the amount of 2 ~ 3m/t steel, silicon-calcium wire to be fed molten steel, line feeding speed is 3 ~ 5m/s, and during line feeding, ladle bottom blowing air supply intensity is 0.0015 ~ 0.0025m
3/ (mint steel), described silicon-calcium wire comprises following component by weight percentage: the Ca of 32% ~ 38%, the Si of 40% ~ 50%, the Fe of 10% ~ 15%, and all the other are inevitable impurity.
According to an embodiment of the method for semisteel smelting low-sulfur steel of the present invention, described method can also comprise soft blow argon 3 ~ 8min after Calcium treatment, and Argon intensity is 0.001 ~ 0.002m
3/ (mint steel).
Compared with prior art, beneficial effect of the present invention comprises: molten iron does not need to carry out pretreatment desulfurizing, avoid desulfurization energy consumption and iron loss of skimming, when improve vanadium extraction terminal (half steel) carbon content and temperature and go out half steel, increasing silicon is carried out to half steel, for converter desulfurization creates good condition, and in converter, adopt the large quantity of slag to smelt, finished product molten steel sulphur content can be controlled within 0.010wt% eventually through measures such as tapping residue adjustment, LF stove desulfurizing and refining, Ca process.
Embodiment
Hereinafter, the method according to semisteel smelting low-sulfur steel of the present invention will be described in detail in conjunction with exemplary embodiment.In the present invention, if do not have the statement made an exception, then in the material usually mentioned, the content of each element or composition is all weight percentage (representing with " wt% ").
The method of semisteel smelting low-sulfur steel can comprise the following steps according to an exemplary embodiment of the present invention: directly molten iron is blended into converter extracting vanadium and carries out blowing to form half steel; Half steel is tapped in ladle, and go out in ladle, add 2 ~ 4Kg/t steel in half steel process ferro-silicon to increase the silicone content in molten steel; Molten steel is blended into converter, then in converter, adds slag making materials and smelt; Outwell the rich sulphur slag in Converter, the high magnesium lime adding 5 ~ 7Kg/t steel to ladle in tapping to the process of ladle mixes with molten steel and rushes, and on the ladle top of the slag, adds slag supplying agent after tapping terminates; Ar blowing refining is carried out to molten steel; Molten steel is carried out desulfurizing and refining at ladle refining furnace; In the mode of feeding calcium alloy line (such as, silicon-calcium wire, solid calcium line, calcium aluminum steel etc.) to molten steel, Calcium treatment is carried out to molten steel; Continuous casting process is adopted to carry out pouring molten steel and obtain sulphur content not higher than the strand of 0.010wt%.
The technological process of production of the method for above-mentioned exemplary embodiment is: vanadium extraction from hot metal → go out half steel increasing silicon → converter smelting → tapping residue adjustment → LF stove (ladle furnace) refining → Ca process → continuous casting.The method reduces molten iron pretreatment desulfurizing operation, avoids desulfurization energy consumption and iron loss of skimming, improves vanadium extraction terminal (half steel) carbon and temperature.
Carry out increasing silicon when going out half steel, the object increasing silicon is the content increasing heating element silicon in half steel, to improve smelting initial stage half steel temperature and to promote that initial smelting period carrys out slag, fast for converter desulfurization creates good condition.Wherein, described ferro-silicon is the conventional alloy of steel-making or reductor, usually, ladle is added as alloy or reductor when steel-making converter is tapped, and the present invention adds opportunity by changing it in semisteel smelting process, just added in ladle when half steel is tapped, become a kind of temperature raising material.When wherein silicone content is 70 ~ 85wt%, its add-on is 2 ~ 4Kg/t steel is the best, makes half steel silicone content higher as add-on crosses senior general, thus supplementary product onsumption when greatly increasing converter smelting; It is not obvious that then half steel as too small in add-on increases silicon, can not play the object of supplementary converter smelting thermal source in early stage.Preferably, described go out half steel process in, when reaching 1/3 of converter extracting vanadium molten steel total amount in tap, ferro-silicon is added in ladle, if it is too early that ferro-silicon adds, a large amount of alloy will be caused to be deposited in ladle bottom, in ladle running process, to there is the danger of blasting; If ferro-silicon adds too late, half steel in the ladle of half steel is housed too much, after adding ferrosilicon, half steel seethes and easily makes half steel overflow ladle, cause metal loss and security incident, and the joining day crosses and lately tapping will be caused to terminate rear alloy can not melt completely, impact increases silicon effect, affects converter and normally smelts.
Large quantity of slag desulfurization is adopted in converter, can further improve converter desulfurization degree, particularly, during converter slag-making, the add-on of quickened lime can be 50 ~ 65Kg/t steel, the add-on of high magnesium lime is 25 ~ 30Kg/t steel, add-on 15 ~ 25Kg/t steel of slag former, described quickened lime, high magnesium lime and slag former are the conventional slag making materials of steel-making.Finished product molten steel sulphur content can be controlled within 0.010% eventually through measures such as tapping residue adjustment, LF stove desulfurizing and refining, Ca process.
In addition, the high magnesium lime adding 5 ~ 7Kg/t steel to ladle in tapping to the process of ladle mixes with molten steel and rushes.Here, if high magnesium lime add-on too much will make tapping process temperature drop large, and very easily show to be piled into " stone roller " at ladle, be difficult to melt, as add-on crosses the object not having at least and improve ladle slag basicity, the too much or very few best effect all not reaching preliminary refining of add-on.The object of mixed punching, mainly in order to improve its melting rate, improves preliminary refining effect.
In one exemplary embodiment of the present invention, the method of semisteel smelting low-sulfur steel also comprises on the basis of the method for above-mentioned exemplary embodiment, after the step of outwelling rich sulphur slag in stove, before converter tapping, the high magnesium lime adding 3 ~ 5Kg/t steel depending on slag situation in converter carries out dry slag, to reduce lower quantity of slag during tapping.If the very few object not having dry slag of high magnesium lime add-on, add-on is excessive, increases smelting cost, and is unfavorable for spattering slag operation, and add-on is that 3 ~ 5Kg/t steel is the most suitable.
In one exemplary embodiment of the present invention, the method for described semisteel smelting low-sulfur steel can be realized by following steps:
(1), molten iron is directly blended into converter extracting vanadium and carries out vanadium extraction blowing to form half steel.And increasing silicon is carried out in half steel tapping process, specific requirement is, when tap reaches 1/3 of converter extracting vanadium molten steel total amount, ferro-silicon in half cylinder of steel, its add-on is 2 ~ 4Kg/t steel, the silicon containing 70 ~ 85wt% in described ferro-silicon.
(2), molten steel is blended into converter, then in converter, add slag making materials carry out desulfurization smelting, wherein, slag making materials can adopt the conventional slag making materials of steel-making, such as, quickened lime, high magnesium lime and slag former, the add-on of slag making materials is large compared with the add-on in existing smelting process, particularly, the total amount that adds of quickened lime is 50 ~ 65Kg/t steel, and the total amount that adds of high magnesium lime is 25 ~ 30Kg/t steel, slag former add total amount 15 ~ 25Kg/t steel.
(3), before tapping, outwell rich sulphur slag in Converter, deslagging backsight slag situation adds t steel 3 ~ 5Kg high magnesium lime dry slag.The high magnesium lime adding 5 ~ 7Kg/t steel to ladle in converter molten steel tapping to the process of ladle mixes with molten steel and rushes, and on the ladle top of the slag, adds slag supplying agent after tapping terminates.The add-on of described slag supplying agent can be 3 ~ 5Kg/t steel, and slag supplying agent comprises the Al of 15 ~ 25% by weight percentage
2o
3, the CaO of 35 ~ 45%, the SiO of 5 ~ 15%
2, 10 ~ 15% metal A l, and the inevitable impurity of surplus.Described slag supplying agent mainly plays the object of preliminary refining, and wherein, the high CaO content of 35 ~ 45% is conducive to improving ladle slag basicity, and the metal A l of 10 ~ 15% can carry out pre-deoxidation to slag, and its acting in conjunction is conducive to refining desulfuration.Make tapping process temperature drop large if add-on crosses senior general, and not easily melt, do not have the effect of preliminary refining, add-on is little then not obvious to ladle slag composition influence, does not also have the effect of preliminary refining.
, tapping terminate after Argon station after converter ar blowing refining is carried out to molten steel, Argon intensity is 0.003 ~ 0.005m
3/ (mint steel), and argon blowing time is 5 ~ 8 minutes.
(5), adopt LF stove to carry out liquid steel refining under the condition of BOTTOM ARGON BLOWING.Namely molten steel adds quickened lime, fluorite, aluminum shot and whipping agent after LF stove refining station in ladle, wherein, the add-on of quickened lime is 2.5 ~ 5Kg/t steel, the add-on of fluorite is 0.5 ~ 1Kg/t steel, the add-on of aluminum shot is 0.3 ~ 0.6Kg/t steel, and the add-on of whipping agent is 5 ~ 6Kg/t steel.Add enough lime before refining and can improve ladle slag basicity, the aluminum shot of 0.3 ~ 0.6Kg/t steel can proceed deoxidation to ladle slag simultaneously, and be more conducive to desulfurization, whipping agent and adding of fluorite are all in order to promotion slag and submerged arc.Then start to add heat refining for the first time, in the process adding heat refining, adopt the first bottom blowing gas intensity to carry out stirring to promote desulfurization, the first bottom blowing gas intensity is 0.003 ~ 0.005m
3/ (mint steel), stops heating after adding heat refining 12 ~ 15min, and improves air supply intensity to the second bottom blowing gas intensity stirring 3 ~ 5min, and described second bottom blowing gas intensity is 0.005 ~ 0.01m
3/ (mint
steel).
Continue in ladle, add quickened lime, fluorite and aluminum shot to carry out second time and add heat refining, wherein, the add-on of quickened lime is 2 ~ 4Kg/t steel, aluminum shot add-on is 0.3 ~ 0.5Kg/t steel, fluorite add-on is 0.5 ~ 0.8Kg/t steel, and adding steel ladle bottom argon blowing air supply intensity in the process of heat refining in second time is 0.003 ~ 0.005m
3/ (mint steel), stops heating after refining 8 ~ 10min.
Finally, 0.005 ~ 0.01m is adopted
3/ (mint
steel) air supply intensity stir after 3 ~ 5min and terminate refining.
Described heating refining process adopts less air supply intensity (0.003 ~ 0.005m
3/ (mint
steel)) object be in order to prevent air supply intensity cross ambassador's molten steel overflow ladle impact produce, stop heating after adopt stronger air supply intensity (0.005 ~ 0.01m
3/ (mint
steel)) object of carrying out stirring is stirring in order to promote in ladle furnace, increase desulfurization kinetics condition, improve refining desulfuration ability.
In the present invention, described aluminum shot is the reductor that steel-making is commonly used, and by weight percentage containing the metallic aluminium being not less than 95%, the granularity of aluminum shot is 5 ~ 10mm.Described quickened lime, fluorite are the auxiliary material that steel-making is commonly used, and by weight percentage, described quickened lime contains the CaO being not less than 86%, and described fluorite contains the CaF being not less than 85%
2.The composition of described whipping agent contains CaO:45 ~ 60%, CaF by weight percentage
2: 5 ~ 10%, burning decrement: 25 ~ 35%, gas forming amount is not less than 45L/Kg.
(6), the refining of LF stove terminates to carry out Calcium treatment to molten steel afterwards, specifically, with the amount of 2 ~ 3m/t steel, silicon-calcium wire is fed molten steel, line feeding speed is 3 ~ 5m/s, slowly activity time will be caused to increase if line feeding speed is crossed, line feeding speed is too fast, and molten steel seethes severity, and temperature drop is large, and molten steel secondary oxidation is serious; During line feeding, ladle bottom blowing air supply intensity is 0.0015 ~ 0.0025m
3/ (mint steel), in calcium line, calcium and molten steel vigorous reaction, make molten steel seethe severity, now should adopt low air supply intensity, prevents molten steel from overflowing ladle and reducing line feeding temperature losses of the process and molten steel secondary oxidation.Silicon-calcium wire comprises following component by weight percentage: the Ca of 32% ~ 38%, the Si of 40% ~ 50%, the Fe of 10% ~ 15%, and all the other are inevitable impurity.
(7), after Calcium treatment terminates, can to molten steel soft blow argon 3 ~ 8min, now bottom blowing gas intensity is 0.001 ~ 0.002m
3/ (mint steel).Molten steel after soft blow directly carries out continuous casting, finally obtains the finished product continuously cast bloom being not more than 0.01%.The object of soft blow is the floating in order to promote inclusion content in melting steel, makes Cleanliness of Molten Steel higher, and during soft blow, Argon intensity is 0.001 ~ 0.002m
3/ (mint steel) is more conducive to inclusion floating.
In order to understand above-mentioned exemplary embodiment of the present invention better, below in conjunction with concrete example, it is further described.
Example 1
Certain factory's molten steel sulfur content is 0.065%, smelts steel grade sulphur content and requires lower than 0.01%.Molten iron is directly blended into converter extracting vanadium and carries out vanadium extraction, go out half steel process adds ferrosilicon (silicone content 70%) increasing silicon from 2Kg/t steel to ladle.The half steel increased after silicon is directly blended into steel-making converter and adds slag making materials and carries out steel desulfurization.The add-on of slag making materials is: the total amount that adds of quickened lime is 58Kg/t steel, and the total amount that adds of high magnesium lime is 30Kg/t steel, slag former add total amount 20Kg/t steel, before tapping, outwell rich sulphur slag in stove, after deslagging, add the high magnesium lime dry slag of 3Kg/t steel.
Tapping process in ladle, add the high magnesium lime of 6Kg/t steel and molten steel is mixed rush, taps after terminating and adds the slag supplying agent of 4Kg/t steel on the ladle top of the slag.Slag supplying agent composition is the Al of 15%
2o
3, the CaO of 35%, the SiO of 5%
2, the metal A l of 12% and inevitable impurity.After tapping terminates, after stove, Argon station adopts 0.003m
3the ladle bottom blowing air supply intensity of/(mint steel) carries out after Argon stirs 5min to molten steel, then molten steel is sent into LF refining desulfuration.
Namely in ladle, quickened lime, fluorite, aluminum shot and whipping agent is added (containing CaO:50%, CaF after molten steel to LF heating station
2: 8%, burning decrement: 30%, gas forming amount: 55L/Kg), quickened lime add-on is 4Kg/t steel, and fluorite add-on is 0.7Kg/t steel, and aluminum shot add-on is 0.5Kg/t steel, and whipping agent add-on is 5Kg/t steel.Start after having added to add heat refining, during heating, steel ladle bottom argon blowing air supply intensity is 0.003m
3/ (mint steel), refining heating 13min stops heating and adopts larger bottom blowing gas intensity to stir 3min, and now bottom blowing gas intensity is 0.005m
3/ (mint steel).Continue to add quickened lime, fluorite and aluminum shot in ladle, the add-on of quickened lime is 3Kg/t steel, and aluminum shot add-on is 0.4Kg/t steel, and fluorite add-on is 0.6Kg/t steel, continues to add heat refining 9min, and during heating, steel ladle bottom argon blowing air supply intensity is 0.004m
3/ (mint steel).Heating terminates the larger air supply intensity of rear employing and stirs 4min, and now bottom blowing gas intensity is 0.005m
3/ (mint steel), LF refining terminates.
Carry out Calcium treatment after heating terminates, the silicon-calcium wire (Ca containing 32%, the Si of 40%, the Fe of 10% and inevitable impurity) of quantitative feeding 2m/t steel in ladle, line feeding speed is 4m/s, and during line feeding, ladle bottom blowing air supply intensity is 0.002m
3/ (mint steel).Calcium treatment terminates rear soft blow 5min, and now bottom blowing gas intensity is 0.0015m
3/ (mint steel), the molten steel after soft blow directly carries out continuous casting, and the sulphur content finally obtaining finished product continuously cast bloom is 0.008%.
Example 2
Certain factory's molten steel sulfur content is 0.04%, smelts steel grade sulphur content and requires lower than 0.01%.Molten iron is directly blended into converter extracting vanadium and carries out vanadium extraction, go out ferrosilicon (silicone content 75%) the increasing silicon adding 3Kg/t steel in half steel process to ladle.The half steel increased after silicon is directly blended into steel-making converter and adds slag making materials and carries out steel desulfurization.The add-on of slag making materials is: the total amount that adds of quickened lime is 50Kg/t steel, and the total amount that adds of high magnesium lime is 28Kg/t steel, slag former add total amount 15Kg/t steel, before tapping, outwell rich sulphur slag in stove, after deslagging, add the high magnesium lime dry slag of 5Kg/t steel.
Tapping process in ladle, add the high magnesium lime of 5Kg/t steel and molten steel is mixed rush, taps after terminating and adds the slag supplying agent of 3Kg/t steel on the ladle top of the slag.Slag supplying agent composition is the Al of 20%
2o
3, the CaO of 30%, the SiO of 10%
2, the metal A l of 10% and inevitable impurity.After tapping terminates, after stove, Argon station adopts 0.004m
3the ladle bottom blowing air supply intensity of/(mint steel) carries out after Argon stirs 7min to molten steel, then molten steel is sent into LF refining desulfuration.
Namely in ladle, quickened lime, fluorite, aluminum shot and whipping agent is added (containing CaO:45%, CaF after molten steel to LF heating station
2: 5%, burning decrement: 25%, gas forming amount: 48L/Kg), quickened lime add-on is 2.5Kg/t steel, and fluorite add-on is 0.5Kg/t steel, and aluminum shot add-on is 0.3Kg/t steel, and whipping agent add-on is 5.5Kg/t steel.Start after having added to add heat refining, during heating, steel ladle bottom argon blowing air supply intensity is 0.004m
3/ (mint steel), refining heating 12min stops heating and adopts larger bottom blowing gas intensity to stir 4min, and now bottom blowing gas intensity is 0.007m
3/ (mint steel).Continue to add quickened lime, fluorite and aluminum shot in ladle, the add-on of quickened lime is 2Kg/t steel, and aluminum shot add-on is 0.3Kg/t steel, and fluorite add-on is 0.5Kg/t steel, continues to add heat refining 8min, and during heating, steel ladle bottom argon blowing air supply intensity is 0.003m
3/ (mint steel).Heating terminates the larger air supply intensity of rear employing and stirs 3min, and now bottom blowing gas intensity is 0.005m
3/ (mint steel), LF refining terminates.
Carry out Calcium treatment after heating terminates, the silicon-calcium wire (Ca containing 35%, the Si of 45%, the Fe of 12% and inevitable impurity) of quantitative feeding 3m/t steel in ladle, line feeding speed is 3m/s, and during line feeding, ladle bottom blowing air supply intensity is 0.0015m
3/ (mint steel).Calcium treatment terminates rear soft blow 3min, and now bottom blowing gas intensity is 0.001m
3/ (mint steel), the molten steel after soft blow directly carries out continuous casting, and finally obtaining finished product continuously cast bloom sulphur content is 0.007%.
Example 3
Certain factory's molten steel sulfur content is 0.08%, smelts steel grade sulphur content and requires lower than 0.01%.Molten iron is directly blended into converter extracting vanadium and carries out vanadium extraction, go out half steel process adds ferrosilicon (silicone content 85%) increasing silicon from 4Kg/t steel to ladle.The half steel increased after silicon is directly blended into steel-making converter and adds slag making materials and carries out steel desulfurization.The add-on of slag making materials is: the total amount that adds of quickened lime is 65Kg/t steel, and the total amount that adds of high magnesium lime is 25Kg/t steel, slag former add total amount 25Kg/t steel, before tapping, outwell rich sulphur slag in stove, after deslagging, add the high magnesium lime dry slag of 3Kg/t steel.
Tapping process in ladle, add the high magnesium lime of 4Kg/t steel and molten steel is mixed rush, taps after terminating and adds the slag supplying agent of 5Kg/t steel on the ladle top of the slag.Slag supplying agent composition is the Al of 25%
2o
3, the CaO of 45%, the SiO of 15%
2, the metal A l of 15% and inevitable impurity.After tapping terminates, after stove, Argon station adopts 0.005m
3the ladle bottom blowing air supply intensity of/(mint steel) carries out after Argon stirs 8min to molten steel, then molten steel is sent into LF refining desulfuration.
Namely in ladle, quickened lime, fluorite, aluminum shot and whipping agent is added (containing CaO:60%, CaF after molten steel to LF heating station
2: 10%, burning decrement: 35%, gas forming amount: 53L/Kg), quickened lime add-on is 5Kg/t steel, and fluorite add-on is 1Kg/t steel, and aluminum shot add-on is 0.6Kg/t steel, and whipping agent add-on is 6Kg/t steel.Start after having added to add heat refining, during heating, steel ladle bottom argon blowing air supply intensity is 0.005m
3/ (mint steel), refining heating 15min stops heating and adopts larger bottom blowing gas intensity to stir 5min, and now bottom blowing gas intensity is 0.01m
3/ (mint steel).Continue to add quickened lime, fluorite and aluminum shot in ladle, the add-on of quickened lime is 4Kg/t steel, and aluminum shot add-on is 0.5Kg/t steel, and fluorite add-on is 0.8Kg/t steel, continues to add heat refining 10min, and during heating, steel ladle bottom argon blowing air supply intensity is 0.005m
3/ (mint steel).Heating terminates the larger air supply intensity of rear employing and stirs 5min, and now bottom blowing gas intensity is 0.01m
3/ (mint steel), LF refining terminates.
Carry out Calcium treatment after heating terminates, the silicon-calcium wire (Ca containing 38%, the Si of 50%, the Fe of 15% and inevitable impurity) of quantitative feeding 2m/t steel in ladle, line feeding speed is 5m/s, and during line feeding, ladle bottom blowing air supply intensity is 0.0025m
3/ (mint steel).Calcium treatment terminates rear soft blow 8min, and now bottom blowing gas intensity is 0.002m
3/ (mint steel), the molten steel after soft blow directly carries out continuous casting, and finally obtaining finished product continuously cast bloom sulphur content is 0.009%.
In sum, the method of semisteel smelting low-sulfur steel of the present invention by reducing molten iron pretreatment desulfurizing operation, go out in half steel process to increase silicon, adopt the measure such as the desulfurization of large quantity of slag slag making materials and tapping residue adjustment, LF stove desulfurizing and refining, Ca process to avoid desulphurization and slag skimming iron loss, semisteel smelting heat source insufficiency in converter, improve desulfuration efficiency also the most at last Finished Steel water sulphur content control within 0.010%.
Although above by describing the present invention in conjunction with exemplary embodiment, it will be apparent to those skilled in the art that when not departing from the spirit and scope that claim limits, various amendment and change can be carried out to exemplary embodiment of the present invention.
Claims (10)
1. a method for semisteel smelting low-sulfur steel, is characterized in that, said method comprising the steps of:
Directly vanadium-bearing hot metal is blended into converter extracting vanadium to carry out blowing to form half steel;
Half steel is tapped in ladle, and going out in half steel process to add ferro-silicon in ladle to increase the silicone content in molten steel;
Molten steel is blended into converter, then in converter, adds slag making materials and smelt;
Outwell the rich sulphur slag in Converter, the high magnesium lime adding 5 ~ 7Kg/t steel to ladle in tapping to the process of ladle mixes with molten steel and rushes, and on the ladle top of the slag, adds slag supplying agent after tapping terminates, and described slag supplying agent comprises the Al of 15 ~ 25% by weight percentage
2o
3, the CaO of 35 ~ 45%, the SiO of 5 ~ 15%
2, 10 ~ 15% metal A l, and the inevitable impurity of surplus;
Ar blowing refining is carried out to molten steel;
Molten steel is carried out desulfurizing and refining at ladle refining furnace, particularly, add the whipping agent of the quickened lime of 2.5 ~ 5Kg/t steel, the fluorite of 0.5 ~ 1Kg/t steel, the aluminum shot of 0.3 ~ 0.6Kg/t steel and 5 ~ 6Kg/t steel in ladle after, starts to add heat refining for the first time; The aluminum shot adding the quickened lime of 2 ~ 4Kg/t steel, the fluorite of 0.5 ~ 0.8Kg/t steel and 0.3 ~ 0.5Kg/t steel again in ladle carries out second time and adds heat refining;
In the mode of feeding calcium alloy line to molten steel, Calcium treatment is carried out to molten steel;
Continuous casting process is adopted to carry out pouring molten steel and obtain sulphur content not higher than the strand of 0.010wt%.
2. the method for semisteel smelting low-sulfur steel according to claim 1, is characterized in that, in described step of being tapped in ladle by half steel, when reaching 1/3 of converter extracting vanadium molten steel total amount in tap, in ladle, adds ferro-silicon.
3. the method for semisteel smelting low-sulfur steel according to claim 1, is characterized in that, the silicon containing 70 ~ 85wt% in described ferro-silicon, its add-on is 2 ~ 4Kg/t steel.
4. the method for semisteel smelting low-sulfur steel according to claim 1, is characterized in that, described slag making materials comprises the slag former of the quickened lime of 50 ~ 65Kg/t steel, the high magnesium lime of 25 ~ 30Kg/t steel and 15 ~ 25Kg/t steel.
5. the method for semisteel smelting low-sulfur steel according to claim 1, it is characterized in that, after outwelling the step of rich sulphur slag in stove described in described method is also included in, before converter tapping, the high magnesium lime adding 3 ~ 5Kg/t steel in converter carries out dry slag, to reduce lower quantity of slag during tapping.
6. the method for semisteel smelting low-sulfur steel according to claim 1, is characterized in that, the add-on of described slag supplying agent is 3 ~ 5Kg/t steel.
7. the method for semisteel smelting low-sulfur steel as claimed in claim 1, it is characterized in that, described Argon intensity of carrying out in ar blowing refining step molten steel is 0.003 ~ 0.005m
3/ (mint steel), and argon blowing time is 5 ~ 8 minutes.
8. the method for semisteel smelting low-sulfur steel according to claim 1, is characterized in that, is describedly carried out at ladle refining furnace in the step of desulfurizing and refining by molten steel, the composition of described whipping agent by weight percentage containing CaO:45 ~ 60%, CaF
2: 5 ~ 10%, burning decrement: 25 ~ 35%, gas forming amount is not less than 45L/Kg; Add in described first time in the process of heat refining and adopt the first bottom blowing gas intensity to stir, described first bottom blowing gas intensity is 0.003 ~ 0.005m
3/ (mint
steel), stop heating after adding heat refining 12 ~ 15min, and improve air supply intensity to the second bottom blowing gas intensity stirring 3 ~ 5min, described second bottom blowing gas intensity is 0.005 ~ 0.01m
3/ (mint
steel);
Add in described second time in the process of heat refining and adopt described first bottom blowing gas intensity to stir, after refining 8 ~ 10min, stop heating; Then, refining is terminated after adopting described second air supply intensity to stir 3 ~ 5min.
9. the method for semisteel smelting low-sulfur steel according to claim 1, it is characterized in that, described to comprise to the mode of molten steel hello calcium alloy line the step that molten steel carries out Calcium treatment: with the amount of 2 ~ 3m/t steel, silicon-calcium wire to be fed molten steel, line feeding speed is 3 ~ 5m/s, and during line feeding, ladle bottom blowing air supply intensity is 0.0015 ~ 0.0025m
3/ (mint steel), described silicon-calcium wire comprises following component by weight percentage: the Ca of 32% ~ 38%, the Si of 40% ~ 50%, the Fe of 10% ~ 15%, and all the other are inevitable impurity.
10. the method for semisteel smelting low-sulfur steel according to claim 1, is characterized in that, described method also comprises soft blow argon 3 ~ 8min after Calcium treatment, and Argon intensity is 0.001 ~ 0.002m
3/ (mint steel).
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Families Citing this family (18)
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| CN103627851B (en) * | 2013-11-14 | 2015-07-08 | 攀钢集团研究院有限公司 | Semisteel steelmaking temperature control method and semisteel steelmaking method |
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| CN111826493B (en) * | 2020-06-30 | 2022-02-01 | 攀钢集团攀枝花钢铁研究院有限公司 | SWRH82B steel and smelting method thereof |
| CN113136479A (en) * | 2021-04-20 | 2021-07-20 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for desulfurizing semi-steel steelmaking converter after furnace |
| CN114774615B (en) * | 2022-04-24 | 2023-08-11 | 黑龙江建龙钢铁有限公司 | Method for producing ultralow-sulfur steel by adopting high-sulfur semisteel |
| CN115449599B (en) * | 2022-10-11 | 2023-09-19 | 安徽富凯特材有限公司 | Molten steel calcium deoxidization method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56123319A (en) * | 1980-03-04 | 1981-09-28 | Nippon Kokan Kk <Nkk> | Production of extra low sulfur steel |
| CN101696462A (en) * | 2009-11-03 | 2010-04-21 | 攀钢集团研究院有限公司 | Method for producing low phosphorus steel by smelting semisteel |
| CN102011062A (en) * | 2010-11-29 | 2011-04-13 | 攀钢集团钢铁钒钛股份有限公司 | Easy-cutting gear steel and smelting method thereof |
| CN102260822A (en) * | 2011-07-27 | 2011-11-30 | 攀钢集团有限公司 | High-phosphorus low-sulfur non-oriented electrical steel and smelting method thereof |
| CN102477472A (en) * | 2010-11-25 | 2012-05-30 | 攀钢集团钢铁钒钛股份有限公司 | Mild steel desulfurization refining method |
| 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 |
-
2013
- 2013-04-15 CN CN201310128818.7A patent/CN103205524B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56123319A (en) * | 1980-03-04 | 1981-09-28 | Nippon Kokan Kk <Nkk> | Production of extra low sulfur steel |
| CN101696462A (en) * | 2009-11-03 | 2010-04-21 | 攀钢集团研究院有限公司 | Method for producing low phosphorus steel by smelting semisteel |
| CN102477472A (en) * | 2010-11-25 | 2012-05-30 | 攀钢集团钢铁钒钛股份有限公司 | Mild steel desulfurization refining method |
| CN102011062A (en) * | 2010-11-29 | 2011-04-13 | 攀钢集团钢铁钒钛股份有限公司 | Easy-cutting gear steel and smelting method thereof |
| CN102260822A (en) * | 2011-07-27 | 2011-11-30 | 攀钢集团有限公司 | High-phosphorus low-sulfur non-oriented electrical steel and smelting method thereof |
| 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 |
Non-Patent Citations (1)
| Title |
|---|
| 圆坯连铸生产45Mn2钢的工艺实践;李平凡;《炼钢》;20121231;第28卷(第6期);第25-27页第1.0工艺流程及铸机参数，2.0冶炼难点及措施，3.0转炉冶炼、3.2LF精炼及表2 * |
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