CN103397132B - Method for enhancing erosion resistance of vanadium extraction converter lining - Google Patents
Method for enhancing erosion resistance of vanadium extraction converter lining Download PDFInfo
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- CN103397132B CN103397132B CN201310289993.4A CN201310289993A CN103397132B CN 103397132 B CN103397132 B CN 103397132B CN 201310289993 A CN201310289993 A CN 201310289993A CN 103397132 B CN103397132 B CN 103397132B
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Abstract
The invention provides a method for enhancing erosion resistance of a vanadium extraction converter lining, which comprises the following steps: adding vanadium-iron-containing water into a vanadium extraction converter, and adding 20-30 kg/tFe manganese-rich ore and 10-25 kg/tFe magnesite into the vanadium-iron-containing water; after the converting starts, adding 20-30 kg/tFe vanadium extraction cooling agent, wherein the converting time is controlled at 5-7 minutes, and the semisteel temperature is controlled at 1400-1450 DEG C; and after the converting finishes, tapping, blowing nitrogen with an oxygen lance to perform slag splashing on the vanadium slag. The invention can effectively solve the problems of poor flowability and difficulty in adhesion of the vanadium slag, and can improve the slag suspension effect, enhance the erosion resistance of the converter lining and effectively prolong the service life of the vanadium extraction converter lining when being used for slag splashing converter protection.
Description
Technical field
The invention belongs to vanadium extraction by converter blowing technical field, specifically, relate to a kind of vanadium slag that adopts converter extracting vanadium is carried out to slag splashing to improve the method for converter extracting vanadium furnace lining corrosion resistance.
Background technology
In the prior art, converter is the main equipment that iron and steel enterprise produces, and its life-span is directly connected to the production cost of converter.Technology of Slag Splashingfor Furnace Maintenance can increase substantially steel-making converter furnace life.
What at present, steel-making converter generally adopted is vertical oxygen marksmanship.Its process characteristic is: utilize top blow oxygen lance to switch nitrogen, splash, through the finishing slag of modification, is coated in converter lining inwall.By the change of spray angle, can on purpose concentrate certain position of splash.Before blowing, add the excessive rhombspar of people and lime, the erosion that has alleviated mutually furnace lining because of oversaturated magnesium oxide slag between the blowing process.In addition, foamy slag forms protective layer on furnace lining.Improving the bonding strength of spattering between slag blanket and backup lining brick the two, is the key of improving slag splashing effect.
Publication number is that the patent documentation of CN1158902A discloses a kind of method that shortens the splashing slag in converter time, the method comprises: in the converting process before tapping, in stove, add light dolomite in batches, its add-on is 8～20 kgs/tonne of steel, after tapping, in residual slag, add slag supplying agent, its add-on is 8～15 kgs/tonne of steel, the chemical composition (% by weight) of slag supplying agent is: magnesia 20～40%, light dolomite 30～60%, magnesite ball 0～30%, unprocessed dolomite 0～35%, add after slag supplying agent, to the high pressure nitrogen of jetting in slag, impact slag, slag is splashed on furnace lining, form the erosion-resistant protective layer of one deck on furnace lining surface, protection furnace lining.
Publication number is that the patent documentation of CN1254018A discloses a kind of method to converter furnace wall slag splashing, the method control spray gun height is apart from furnace bottom 0.7m～3.0m, airshed 250～600Nm3/min, preferably slag solid rate is 0.5～0.7, add the slag solidifying agent containing MgO or CaO by residue composition after gas injection, control disperse height and to furnace wall fixed amount of slag.
Publication number is that the patent documentation of CN1377976A discloses a kind of converter retaining operation method of preventing splash slag that reduces iron loss, the method is mainly to add carbon containing reducer coal dust, coke powder or Graphite Powder 99 etc. to slag liquid surface in stove before converter tapping or in tapping process, with (FeO) in reducing slag liquid, improve slag viscosity and fusing point, reach the object of slag splashing.
Publication number is the protecting method with splash slag that the patent documentation of CN101177720A discloses a kind of converter hyperoxia voltinism slag, the method comprises: converter has gone out after steel, in converter, leave slag, be blown into nitrogen with furnace roof oxygen rifle, start to be blown into after nitrogen in stove at furnace roof oxygen rifle, in converter, add the slag supplying agent being formed by hard coal and magnesium oxide, the add-on of slag supplying agent is: slag per ton adds 30～double centner slag supplying agent, the terminal slag of converter steelmaking is splash and is bonded on furnace wall, form and spatter slag blanket.
Publication number is that the patent documentation of CN102424886A discloses a kind of decarburization converter less-slag slag splashing technique, and this technique comprises: adopt desiliconization of hot metal, dephosphorization, desulfurization half molten steel to carry out converter smelting, no longer add steel scrap; In control slag, MgO content is in 11% ± 0.5% scope; And control basicity of slag in 3.5≤R≤4.0, TFe≤25% in slag; Adopt lime slag making, according to MgO content in light dolomite with addition of 15～30% of lime adding amount; Spattering the front molten bath of slag stays the quantity of slag to be greater than the critical quantity of slag 45～55kg/t that stays that ensures to spatter slag effect; Blow end point control adopts not stove directly to tap, and directly spatters slag; Adopt low rifle position to spatter slag, start to spatter slag rifle position and keep basic blowing rifle position 1.5m, while spattering the slag time to 50%, rifle potential drop is low to moderate 1.2m; Spatter slag time 3～5min; Spatter and ensure to stay the quantity of slag 5～15kg/t after slag, and the quantity of slag 45～65kg/t is stayed in molten bath while ensureing that lower stove spatters slag.
But, above-mentioned prior art all steel-making converter be object, do not relate to converter extracting vanadium slag splashing.For converter extracting vanadium, its production has singularity, is therefore necessary converter extracting vanadium to carry out slag splashing to extend its life-span.
Summary of the invention
The object of the invention is to solve at least one in the deficiencies in the prior art.
For example, one of object of the present invention is to provide a kind of method that can reduce lining erosion in vanadium extraction by converter blowing production process.
The invention provides a kind of method that improves converter extracting vanadium furnace lining corrosion resistance, said method comprising the steps of: vanadium-bearing hot metal is added to converter extracting vanadium, and add the rich manganese ore of 20～30kg/tFe and the magnesia of 10～25kg/tFe in vanadium-bearing hot metal; After blowing starts, add the vanadium-raising cooling agent of 20～30kg/tFe, duration of blast control is 5～7min, and half steel temperature is controlled to 1400～1450 DEG C; After finishing blowing, tapping, and vanadium slag is spattered to slag operation by oxygen lance spraying nitrogen blowing.
Compared with prior art, technique effect of the present invention comprises: can effectively solve vanadium slag poor fluidity, the difficult problem adhering to, while carrying out slag splashing, can improve dross effect, improve furnace lining erosion resistibility, effectively improve converter extracting vanadium lining life.
Embodiment
Hereinafter, describe the method for raising converter extracting vanadium furnace lining corrosion resistance of the present invention in detail in connection with exemplary embodiment.
For converter extracting vanadium, because tap to tap time is short, temperature is low, in slag, eutectic mixture composition is few, slag fluidity is poor, and before arriving extraction smelting of vanadium terminal, in molten iron, C react inabundant expansion, PCO, PCO in furnace gas with O
2lower, and PO
2higher, slag bad adhesion, causes magnesia carbon brick to be exposed in oxygen atmosphere, impels C and O
2reaction, the above lining erosion speed of iron liquid level is below iron liquid level.The above furnace lining of iron liquid level is by the mode repeated action that the direct decarburization of oxygen → loose embrittlement → erosion is peeled off → reoxidized substantially, and brick body is deteriorated gradually.In addition, produce vanadium rate for improving as far as possible, extraction smelting of vanadium is stricter to Control for Kiln Temperature, conventionally can adopt the mode that adds part pig to carry out auxiliary temperature-reducing.So charging side is not only subject to the impact of molten iron, also to be subject to the impact of pig, because furnace temperature is low, it is block that slag is, and when blowing, together with molten iron, operational layer brick carried out to omnidistance rigid mechanical shock, therefore mechanical shock is the major cause of converter extracting vanadium converter bottom and body bottom damage.Different from steel-making converter, the vanadium slag fusing point that converter extracting vanadium is produced is low, high containing vanadium, low containing MgO, dross difficulty while spattering slag, and difficulty is larger than steel-making converter.
In the case of the These characteristics that takes into full account converter extracting vanadium, contriver provides a kind of method that improves converter extracting vanadium furnace lining corrosion resistance.Said method comprising the steps of: vanadium-bearing hot metal is added to converter extracting vanadium, and add the rich manganese ore of 20～30kg/tFe and the magnesia of 10～25kg/tFe in vanadium-bearing hot metal; After blowing starts, add the vanadium-raising cooling agent of 20～30kg/tFe, duration of blast control is 5～7min, and half steel temperature is controlled to 1400～1450 DEG C; After finishing blowing, tapping, and vanadium slag is spattered to slag operation by oxygen lance spraying nitrogen blowing.
In the method for the invention, the composition of vanadium-raising cooling agent by weight percentage can be by CaO<0.5%, TFe>55%, MgO<3%, Al
2o
3<5%, SiO
2<8%, TiO
2<5% and a small amount of impurity composition.
In an exemplary embodiment of the method for raising converter extracting vanadium furnace lining corrosion resistance of the present invention, described method can also be included in open blow 30s time period (, blow the beginning open to opening the time period that the time of blowing is 30s from opening) be 1200～1500mm by control of lance position, time period at oxygen blast 30～300s is 1000～1200mm by control of lance position, oxygen blast 300s to the time period of finishing blowing be 1200～1500mm by control of lance position.
In an exemplary embodiment of the method for raising converter extracting vanadium furnace lining corrosion resistance of the present invention, spatter oxygen lance position in slag step and be preferably 450～550mm, nitrogen pressure is preferably 0.9～1.5MPa, spatters the slag time to be preferably 1～3min.
In the method for the invention, MnO in rich manganese ore
2content is greater than 35%, and the MgO content in magnesia is greater than 92%, and the granularity of the two is all less than 10mm.
The main component of the vanadium slag that method of the present invention obtains comprises: V
2o
514%～16%, SiO
216%～18%, MgO6%～8%, the ferriferous oxide of MnO8%～12% and surplus and impurity.And hemisphere point temperature (can the regard fusing point as) scope of this vanadium slag is: 1300～1340 DEG C, viscosity is between 2.0～3.0 pools.
Method of the present invention is in the case of the normal process for extracting vanadium that does not affect converter extracting vanadium, by vanadium slag is carried out to residue adjustment modifying process, thereby reduce fusing point, the raising vanadium slag adhesivity of vanadium slag, in the time that vanadium slag has better dross effect, adopt the winding-up of the low rifle of nitrogen position to spatter slag, after vanadium slag adheres on furnace lining, can play the effect that slows down lining erosion speed.
In order to understand better the present invention, further illustrate the method for raising converter extracting vanadium furnace lining corrosion resistance of the present invention below in conjunction with concrete example.
Example 1
The vanadium-bearing hot metal that blast furnace ironmaking is obtained is blended into after converter extracting vanadium, adds the rich manganese ore of 30kg/tFe and the magnesia of 10kg/tFe, after blowing starts, adds the vanadium-raising cooling agent of 20kg/TFe.In this example, the concrete composition of vanadium-raising cooling agent is by weight: CaO0.5%, TFe57%, MgO2.6%, Al
2o
33.75%, SiO
27.33%, TiO
24.2% and a small amount of impurity.
Oxygen lance position adopts " high-low-high " pattern to control (, open that to blow oxygen lance position within 30s be 1200mm, the time period oxygen lance position of oxygen blast 30～300s is 1000mm, oxygen blast 300s is 1200mm to finishing front oxygen lance position), duration of blast is controlled at 5min, and half steel temperature is controlled to 1400～1450 DEG C.After finishing blowing, go out half steel, vanadium slag is stayed in converter, and oxygen rifle gas is switched to nitrogen, again descends rifle to spatter slag operation, and rifle position controls to 500mm, and nitrogen pressure is controlled at 1MPa, spatters slag time 3min, spatter slag after furnace lining thicken about 10mm.
The main component of the vanadium slag that this example obtains comprises V
2o
515.3%, SiO
216.1%, MgO6.9%, the ferriferous oxide of MnO8.8% and surplus and impurity.And the hemisphere point temperature of vanadium slag is: 1338 DEG C, viscosity 2.7 is moored.
Example 2
The vanadium-bearing hot metal that blast furnace ironmaking is obtained is blended into after converter extracting vanadium, adds the rich manganese ore of 20kg/tFe and the magnesia of 25kg/tFe, after blowing starts, adds the vanadium-raising cooling agent of 30kg/TFe.In this example, the concrete composition of vanadium-raising cooling agent is by weight: CaO0.4%, TFe59%, MgO1.6%, Al
2o
32.5%, SiO
26.9%, TiO
22.7% and a small amount of impurity.
Oxygen lance position adopts " high-low-high " pattern to control (, open that to blow oxygen lance position within 30s be 1500mm, the time period oxygen lance position of oxygen blast 30～300s is 1200mm, oxygen blast 300s is 1500mm to finishing front oxygen lance position), duration of blast control is 7min, and half steel temperature is controlled within the scope of 1400～1450 DEG C.After finishing blowing, go out half steel, vanadium slag is stayed in converter, and oxygen rifle gas is switched to nitrogen, again descends rifle to spatter slag operation, and rifle position controls to 500mm, and nitrogen pressure is controlled at 1MPa, spatters slag time 2min, spatter slag after furnace lining thicken about 12mm.
The main component of the vanadium slag that this example obtains comprises V
2o
514.2%, SiO
217.4%, MgO7.6%, the ferriferous oxide of MnO11.8% and surplus and impurity.And the hemisphere point temperature of vanadium slag is: 1305 DEG C, viscosity 2.0 is moored.
Example 3
The vanadium-bearing hot metal that blast furnace ironmaking is obtained is blended into after converter extracting vanadium, adds the rich manganese ore of 25kg/tFe and the magnesia of 20kg/tFe, after blowing starts, adds the vanadium-raising cooling agent of 25kg/TFe.In this example, the concrete composition of vanadium-raising cooling agent is by weight: CaO0.5%, TFe62%, MgO2.2%, Al
2o
31.4%, SiO
27.2%, TiO
23.8% and a small amount of impurity.
Oxygen lance position adopts " high-low-high " pattern to control (, open that to blow oxygen lance position within 30s be 1300mm, the time period oxygen lance position of oxygen blast 30～300s is 1100mm, oxygen blast 300s is 1400mm to finishing front oxygen lance position), duration of blast is controlled at 6min, and half steel temperature is controlled to 1400～1450 DEG C.After finishing blowing, go out half steel, vanadium slag is stayed in converter, and oxygen rifle gas is switched to nitrogen, again descends rifle to spatter slag operation, and rifle position controls to 500mm, and nitrogen pressure is controlled at 1MPa, spatters slag time 1min, spatter slag after furnace lining thicken about 8mm.
The main component of the vanadium slag that this example obtains comprises V
2o
515.9%, SiO
216.6%, MgO7.9%, the ferriferous oxide of MnO10.3% and surplus and impurity.And the hemisphere point temperature of vanadium slag is: 1323 DEG C, viscosity 2.1 is moored.
In sum, method of the present invention can effectively solve poor, the difficult problem adhering to of vanadium slag melting, while carrying out slag splashing, can improve dross effect, improves furnace lining erosion resistibility, effectively improves converter extracting vanadium lining life.
Although described the present invention in conjunction with exemplary embodiment above, those of ordinary skill in the art should be clear, in the case of not departing from the spirit and scope of claim, can carry out various amendments to above-described embodiment.
Claims (5)
1. a method that improves converter extracting vanadium furnace lining corrosion resistance, is characterized in that, said method comprising the steps of:
Vanadium-bearing hot metal is added to converter extracting vanadium, and add the rich manganese ore of 20～30kg/tFe and the magnesia of 10～25kg/tFe in vanadium-bearing hot metal;
After blowing starts, add the vanadium-raising cooling agent of 20～30kg/tFe, duration of blast control is 5～7min, and half steel temperature is controlled to 1400～1450 DEG C;
After finishing blowing, tapping, and vanadium slag is spattered to slag operation by oxygen lance spraying nitrogen blowing, wherein,
The composition of described vanadium-raising cooling agent is by weight percentage by CaO<0.5%, TFe>55%, MgO<3%, Al
2o
3<5%, SiO
2<8%, TiO
2<5% and a small amount of impurity composition.
2. the method for raising converter extracting vanadium furnace lining corrosion resistance according to claim 1, it is characterized in that, described method is also included in and opens the time period of blowing 30s is 1200～1500mm by control of lance position, time period at oxygen blast 30～300s is 1000～1200mm by control of lance position, oxygen blast 300s to the time period of finishing blowing be 1200～1500mm by control of lance position.
3. the method for raising converter extracting vanadium furnace lining corrosion resistance according to claim 1, is characterized in that, described in to spatter oxygen lance position in slag step be 450～550mm, nitrogen pressure is 0.9～1.5MPa, spattering the slag time is 1～3min.
4. the method for raising converter extracting vanadium furnace lining corrosion resistance according to claim 1, is characterized in that, MnO in described rich manganese ore
2content is greater than 35%, and its granularity is less than 10mm.
5. the method for raising converter extracting vanadium furnace lining corrosion resistance according to claim 1, is characterized in that, in described magnesia, MgO content is greater than 92%, and its granularity is less than 10mm.
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111518983A (en) * | 2020-04-08 | 2020-08-11 | 东北大学 | Manganese vanadium slag and method for manufacturing manganese vanadium slag by converter |
| CN111733309B (en) * | 2020-07-13 | 2022-04-19 | 首钢集团有限公司 | Cooling method and cooling system for converter lining |
| CN112280930A (en) * | 2020-10-30 | 2021-01-29 | 攀钢集团攀枝花钢钒有限公司 | Method for controlling furnace-splashing furnace-protecting gun position of steelmaking converter |
| CN112501380B (en) * | 2020-11-30 | 2022-03-29 | 钢铁研究总院 | Top-blown oxygen lance, vanadium extraction top-bottom combined blowing method and vanadium extraction smelting method |
| CN115074481A (en) * | 2022-07-08 | 2022-09-20 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for improving chemical heat of vanadium extraction semisteel |
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| JP5552846B2 (en) * | 2010-03-09 | 2014-07-16 | 新日鐵住金株式会社 | Converter refractory protection method for converter |
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| CN102127613A (en) * | 2011-02-25 | 2011-07-20 | 河北钢铁股份有限公司承德分公司 | Method for extracting vanadium through composite blowing of converter |
| CN102912069A (en) * | 2012-10-31 | 2013-02-06 | 攀钢集团研究院有限公司 | Low-cost slag splashing protection method of vanadium extraction converter |
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