EP0043238B1 - Procédé de déphosphoration d'un bain de fonte - Google Patents

Procédé de déphosphoration d'un bain de fonte Download PDF

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Publication number
EP0043238B1
EP0043238B1 EP19810302859 EP81302859A EP0043238B1 EP 0043238 B1 EP0043238 B1 EP 0043238B1 EP 19810302859 EP19810302859 EP 19810302859 EP 81302859 A EP81302859 A EP 81302859A EP 0043238 B1 EP0043238 B1 EP 0043238B1
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EP
European Patent Office
Prior art keywords
pig iron
molten pig
dephosphorization
blowing
flux
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19810302859
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German (de)
English (en)
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EP0043238A1 (fr
Inventor
Hitoshi Morishita
Hajime Bada
Fumio Sudo
Shuji Takeuchi
Toshihiko Emi
Tsutomu Nozaki
Rinzo Tachibana
Sumio Yamada
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JFE Steel Corp
Original Assignee
Kawasaki Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP8808180A external-priority patent/JPS5713110A/ja
Priority claimed from JP2083081A external-priority patent/JPS57137408A/ja
Priority claimed from JP7472081A external-priority patent/JPS57192210A/ja
Application filed by Kawasaki Steel Corp filed Critical Kawasaki Steel Corp
Publication of EP0043238A1 publication Critical patent/EP0043238A1/fr
Application granted granted Critical
Publication of EP0043238B1 publication Critical patent/EP0043238B1/fr
Expired legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00—Refining of pig-iron; Cast iron
    • C21C1/02—Dephosphorising or desulfurising
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/34—Blowing through the bath
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/35—Blowing from above and through the bath

Definitions

  • This invention relates to a method of dephosphorizing molten pig iron, and more particularly it is to provide a method of dephosphorizing molten pig iron wherein an oxygen bottom-blown or top and bottom-blown converter or other similar vessels is used as a refining vessel, molten pig iron is charged into the refining vessel, a powdery refining agent consisting mainly of lime is blown from the bottom of the refining vessel into molten pig iron together with a refining gas, particularly oxygen gas as a carrier gas to perform desiliconization and subsequent dephosphorization of molten pig iron.
  • a refining gas particularly oxygen gas as a carrier gas to perform desiliconization and subsequent dephosphorization of molten pig iron.
  • soda ash possesses both high dephosphorization and desulfurization ratios, but its unit cost is high. Further, the evaporation loss is large in the use, so that it is difficult to perform high- temperature treatment. And also, the erosion of refractory is conspicuous and hence the material cost becomes higher.
  • the conventional technics for preliminary dephosphorization treatment of molten pig iron including the above mentioned processes generally take a long time of approximately 20 minutes or more, so that they come into question in view of productivity.
  • the inventors have aimed at dephosphorization behavior appeared at an initial blowing stage in a bottom-blown converter capable of easily achieving an equilibrium between slag and metal. That is, as apparent from Fig. 1 illustrating an example of variations of phosphorus content in molten metal during the oxygen blowing, the reduction of phosphorus content is caused at an initial blowing, i.e. until the total oxygen blowing quantity reaches approximately 20 Nm 3 per ton of molten metal at an oxygen blowing rate of 3 Nm 3 /min.t (in 6-7 minutes after the start of the blowing). Moreover, if iron ore is added as an auxiliary material during the blowing, the total oxygen blowing quantity may include oxygen produced from the iron ore (1 kg of the iron ore produces oxygen gas corresponding to 0.2 Nm3).
  • the ultimate phosphorus content is 0.040-0.070% at most. Therefore, it is still insufficient to apply the dephosphorization behaviour at the initial blowing stage in the bottom-blown converter as it is to the preliminary dephosphorization treatment for molten pig iron.
  • the inventors have made further investigations and experiments with respect to conditions for reducing the ultimate phosphorus content at the above initial blowing stage of the bottom-blown converter to a value suitable as the preliminary dephosphorization treatment for molten pig iron, and as a result it has been found that a considerably low ultimate phosphorus content can advantageously be realized by the method as mentioned below in a very short time without substantially producing oxidation loss of manganese, whereby the bottom-blown converter can properly be utilized for the preliminary dephosphorization treatment of molten pig iron.
  • a method of dephosphorizing molten pig iron wherein said molten pig iron is charged into a refining vessel provided at its bottom with tuyeres for blowing gas and if necessary, at its top with a gas injecting member, a powdery refining agent together with said blowing gas is blown into said molten pig iron through said tuyeres, while a flux for said refining agent is charged into said refining vessel to perform desiliconization and subsequent dephosphorization of said molten pig iron, which comprises:
  • the bottom-blown converter using an oxygen gas as a blowing gas is effectively utilized for the dephosphorization of molten pig iron.
  • the invention is applicable to oxygen refining furnaces or other similar vessels such as top and bottom-blown converter and the like as far as they have functions similar to those of the bottom-blown converter.
  • the invention is advantageously adaptable to overcome various problems in the steel-making step because the thus treated molten pig iron is applicable to, for example, a slagless converter.
  • net oxygen quantity means to be a total oxygen quantity during the blowing including oxygen quantity produced from the charge of iron ore as the coolant but excluding oxygen quantity consumed by the desiliconization reaction.
  • molten pig iron having a chemical composition of about 4.6% of C, 0.2-0.4% of Si, about 0.4% of Mn, about 0.14% of P, about 0.02% of S and the remainder of Fe is tapped out from the blast furnace and charged into the bottom-blown converter or top and bottom-blown converter at a temperature of about 1,380°C together with a necessary amount of iron ore or manganese ore for controlling the temperature rise of molten pig iron accompanied with the blowing treatment, and then a powdery refining agent is blown into molten pig iron from the bottom of the converter together with oxygen gas as a carrier gas.
  • each value of dephosphorization and demanganization ratios taken on the ordinate is given by the following equation: wherein E represents a phosphorus or manganese content of molten pig iron, suffix i is the case before treatment and suffix f is the case after treatment, while the value of slag basicity (Ca0/Si0 2 ) taken on the abscissa is given by increasing or decreasing the amount of CaO on the basis of 30 kg/t. Moreover, a solid line represents the dephosphorization ratio and a broken line represents the demanganization ratio.
  • the dephosphorization ratio in the conventional oxygen bottom-blown converter is shown by a dot-dash line in Fig. 2, from which it is obvious that the value of the resulting slag basicity CaO/S'0 2 changes within a range of 2-3 at an initial blowing stage, i.e. over 6, 7 minutes after the start of the blowing, during which the dephosphorization ratio reaches only about 60%.
  • the higher the slag basicity (CaO/SiO 2 ) after the treatment the higher the dephosphorization ratio and the lower the demanganization ratio. That is, when the value of CaO/S'0 2 is not less than 2.5, the conspicuous increase of dephosphorization ratio and reduction of demanganization ratio are simultaneously realized, while when CaO/S'0 2 value is less than 2.5, the dephosphorization ratio is not improved so much and the reduction of demanganization ratio is insufficient.
  • the basicity is too high (i.e. it exceeds 6)
  • the addition effect of CaO tends to be saturated and the excessive consumption of CaO brings about the increase of procedure cost.
  • an abscissa represents the net oxygen quantity, i.e. oxygen quantity obtained by subtracting the oxygen quantity consumed in the desiliconization from the sum of oxygen quantity produced from the charged iron ore and the like and oxygen quantity to be blown.
  • the net oxygen quantity is less than 8 Nm 3 per ton of molten pig iron
  • the dephosphorization ratio of at least about 85% required for the preliminary dephosphorization treatment of molten pig iron cannot be obtained, while when the net oxygen quantity is not less than 8 Nm 3 /t, the sufficiently high dephosphorization ratio can be obtained.
  • the carbon content of molten pig iron is necessary to be about 3.0%. Therefore, the net oxygen quantity is necessary to be not more than 15 Nm 3 /t in order to avoid the decarburization exceeding the above carbon content.
  • the influence of treating temperature on the dephosphorization ratio is examined by increasing or decreasing the amount of iron ore as a coolant to be charged together with molten pig iron into the refining vessel to vary the temperature of molten pig iron within a range of 1,300-1,500 0 C under such a condition that the slag basicity (CaO/Sio 2 ) after the treatment is adjusted to 3.7-4.2 by using 30 kg/t of CaO as the powdery refining agent and the amount of CaF 2 corresponding to 13.3% of the CaO amount and the measured results are shown in Fig. 4, from which it can be seen that the lower the treating temperature, the higher the dephosphorization ratio.
  • a coolant use may be made of iron ore, manganese ore, mill scale, scrap and the like.
  • the dephosphorization ratio of not less than 85% at the preliminary dephosphorization treatment of molten pig iron is usually 0.1-0.16%, while the phosphorus content required for slagless refining is 0.02%, so that it is required to obtain the dephosphorization ratio of at least 85% at the preliminary dephosphorization treatment of molten pig iron.
  • the upper limit of the treating temperature satisfying the above requirement is 1,450°C, while the lower limit is required to be 1,250°C so as to prevent the solidification of molten metal due to the temperature drop up to subsequent step.
  • iron ore as a coolant is charged into the top and bottom-blown converter in an amount enough to control the temperature of molten pig iron to 1,370°C together with molten pig iron.
  • oxygen gas is blown from the bottom of the converter into molten pig iron together with 30 kg/t of CaO as a powdery refining agent and CaF 2 corresponding to 13.3% of the CaO amount in such a manner that the net oxygen quantity inclusive of oxygen quantity produced from the iron ore is 12-14 Nm 3 per ton of molten pig iron.
  • the dephosphorization ratio is measured by changing the oxygen bottom-blowing quantity to 3 Nm 3 /min.t, 0.8 Nm3/min.t and 0.3 Nm 3 /min.t, respectively.
  • the dephosphorization ratio of not less than 85% is achieved by blowing oxygen gas from the bottom of the converter at a rate of not less than 0.5 Nm 3 /min per ton of molten pig iron with good stirring.
  • Fig. 1 When the preliminary dephosphorization treatment of molten pig iron according to the invention satisfying all of four requirements as described above is shown in Fig. 1 as a function of the net oxygen quantity, it is apparent that the conspicuous reduction of phosphorus content (shown by broken line) is realized in a very short time as compared with that at the initial blowing stage in the conventional bottom-blown converter.
  • the slag usable for the dephosphorization is important to include a large amount of iron oxide in addition to the high basicity.
  • the invention does not need the addition of iron oxide to the slag as apparent from the above mentioned experimental results, which is quite opposite to the common sense relating to the slag conditions in the conventional dephosphorization due to oxidation.
  • the flux serves to promote the slag formation of the powdery refining agent and is charged into molten pig iron in the following manners:
  • the flux mention may be made of fluorite (CaF 2 ), soda ash (Na 2 C0 3 ), cryolite, colemanite, red mud and the like.
  • the flux is used in an amount of 2 to 30% by weight per the powdery refining agent (CaO).
  • the red mud may be used in an amount of 10-45% by weight.
  • the fluorite as a flux is added together with the powdery refining agent to molten pig iron, whereby the viscosity of the resulting slag is lowered during the treatment to enlarge the reaction surface area against molten pig iron and hence the dephosphorization effect is enhanced.
  • the addition of powdery fluorite passing through tuyeres at the bottom of the vessel increases a chance of contacting with powdery lime as a refining agent, which is effective for early and surely lowering the slag viscosity.
  • Figs. 6a and 6b are shown influences of CaF 2 and NaC03 as a powdery flux to be mixed with the powdery refining agent on both the dephosphorization and demanganization ratios, respectively.
  • the value of basicity (CaO/Si0 2 ) after the treatment is adjusted to a range of 3.7-4.2 by using 30 kg/t of CaO, and the amount of CaF 2 or Na 2 CO 3 is varied up to 30% by weight per CaO.
  • the temperature of molten metal after the treatment is controlled to approximately 1,370°C.
  • the amount of flux is preferable within a range of 7-30% by weight, which is due to the fact that the resulting slag is softened to increase the rate of reaction as a result of the observation of reaction system.
  • the fluorite as a flux is available as a lumpy material. Therefore, it is necessary to pulverize the lumpy fluorite in order to blow the powdery flux together with the powdery refining agent into molten pig iron as in the case (i).
  • the use of large grinding equipment is required in addition to the power and fuel.
  • various installations such as pipelines for transporting from the grinding equipment to steel-making factory, pipeline for carrier gas, storage tanks and the like. Therefore, there may be caused problems such as the increase of maintenance cost for these installations or the like.
  • the inventors have made experiments with the case (ii) and found out that an unexpectedly better effect is obtained when the lumpy fluorite is directly charged onto molten pig iron from the top of the refining vessel.
  • the charging of lumpy fluorite can be performed by applying a chute for auxiliary material always installed in a usual steel-making factory without using many installations inclusive of the aforementioned grinding equipment, and as a result, the dephosphorization ratio equal to or higher than that of the prior art is obtained, which is related to considerable reduction of treatment cost in molten pig iron.
  • the minimum addition amount of fluorite required for obtaining the dephosphorization ratio of 85% is 5% by weight per lime in case of blowing the powdery fluorite together with the powdery lime from the bottom tuyeres and approximately 2% by weight in case of charging the lumpy fluorite from the top of the vessel.
  • the comparison of the cases (i) and (ii) with respect to only the dephosphorization ratio is shown in Fig. 8.
  • the amount of the flux used for effectively promoting the dephosphorization performance can be reduced in a high contribution ratio together with the omission of the pulverizing work for the flux.
  • the invention is an epochal dephosphorization method adaptable for usual molten pig irons. Further, the invention is effective for the dephosphorization of low-silicon molten pig iron having a silicon content of, for example, not more than 0.15%.
  • the dephosphorization ratio of at least 85% can be realized in the low-silicon molten pig iron by controlling the amounts of the powdery refining agent and flux charged to a certain extent under conditions satisfying the previously mentioned four requirements.
  • Fig. 9 is shown a relation between the amount of CaO and the dephosphorization ratio when molten pig iron having a silicon content of not more than 0.15% is dephosphorized at the treating temperature of 1,350°C with 3 kg/t of fluorite as a flux by varying the amount of CaO.
  • Fig. 10 is shown a relation between the consumption of fluorite as a flux and the dephosphorization ratio when molten pig iron having a silicon content of not more than 0.15% is dephosphorized at the treating temperature of 1,350°C with 20 ⁇ 2 kg/t of CaO as a powdery refining agent by varying the amount of the fluorite.
  • soda ash, cryolite, colemanite or red mud as a flux, similar results are obtained.
  • powdery flux when charging the flux into the refining vessel, powdery flux may be blown into molten pig iron together with the powdery refining agent and bottom-blowing gas, or lumpy flux may be charged onto molten pig iron from the top of the vessel.
  • the dephosphorization ratio can effectively be achieved by the preliminary dephosphorization treatment of molten pig iron to such an extent that dephosphorization operation at subsequent step is not required anymore. Therefore, if the dephosphorization is carried out at the subsequent step, the production of super-low phosphorus steel can simply and easily be realized.
  • the dephosphorization ratio reached about 93% and Na 2 CO 3 had substantially the same activity as CaF 2 .
  • the treatment of the molten pig iron of about 250 tons according to the invention needs only about 2-3 minutes, while the conventional treatment using CaO needs 15-40 minutes. Accordingly, the invention can noticeably reduce the treating time and is not only advantageous in view of the productivity but also the ultimate phosphorus content is very low.
  • the above described conventional treatment is only to reduce a load of dephosphorization in the refining in the next step of converter, while in the treatment of the invention, the dephosphorization can be effectively carried out to such an extent that the dephosphorization in the next step is not necessary and therefore if dephosphorization is added in the next step of refining in converter, super-low phosphorus steel can be simply and easily made.
  • Fe and the dephosphorization can be advantageously carried out at low temperatures by using iron ore and other iron series coolant and the reduction of the coolant can be completely carried out, so that the yield of iron is high and T-Fe in the slag is low, so that the durable life of the refractory is not adversely affected and the erosion of the refractory can be advantageously reduced and an amount of slag formed is small.
  • the converter refining of molten pig iron having a level of Si of 0.30% even in the best condition, about 70 kg/t of slag is formed, while in the invention, the T orma- tion of slag is reduced to about 35 kg/t. Accordingly, if the treatment of molten pig iron according to the invention and the subsequent slagless refining are combined, the amount of slag formed in steel making step can be broadly reduced.
  • the remarkable desulfurizing function is far more highly realized than the usual refining in converter and in the usual steel making, the desulfurizing step is not necessary and in low sulfur steel making, the load in the desulfurizing step can be remarkably reduced and this is shown in Fig. 11.
  • This example illustrates the case where a lumpy flux of fluorite is charged into a bottom-blown converter from a top opening and the other treating manners follow to the manner as mentioned in the preceding examples.
  • the treating conditions in this example are shown in Table 6.
  • Table 6 shows also the results in the above mentioned process wherein the powdery refining agent and the powdery flux are blown with bottom-blowing oxygen into the converter, for comparison with the results in this example.
  • the cost for pulverizing fluorite (electric powder and heating cost for removing water) becomes zero and maintenance cost of installation for pulverising fluorite and transportation pipes is not necessary.
  • a pulverizer for fluorite has been needed other than a pulverizer for calcium oxide but the pulverizer for fluorite is not needed and the installation cost can be lowered.
  • the amount of the flux used can be reduced without decreasing the dephosphorizing activity as compared with the case where the powdery refining agent and the powdery flux are blown with an oxygen blowing gas into the bottom-blown converter and the pulverizing process may be omitted.
  • a bottom-blown converter was used as the refining vessel bu the top and bottom-blown converter may be used.
  • a bottom-blown converter was used as a refining vessel, as far as the vessel has the similar function thereto, a top and bottom-blown converter in which top-blowing oxygen can be blown into the converter and the other iron making vessels having the similar function may be applied to the invention as a refining vessel.
  • the dephosphorization in the pretreatment of a low 5I pig iron having Si content of less than 0.15% by weight, the dephosphorization can be effectively attained to such an extent that the dephosphorization in the subsequent step is not necessary and when the dephosphorization is added in the next step of refining in converter, the super-low phosphorus steels can be simply and easily made.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Claims (11)

1. Procédé pour déphosphorer de la fonte en gueuse ou fonte de première fusion, selon laquelle ladite fonte en gueuse est chargée dans une cuve d'affinage pourvu dans son fond de tuyères pour souffler du gaz et si nécessaire, pourvue dans son dessus d'un élément d'injection de gaz, un agent d'affinage pulvérulent étant conjointement avec ledit gaz de soufflage soufflé dans ladite fonte en gueuse par l'intermédiaire des dites tuyères, tandis qu'un fondant pour ledit agent d'affinage est chargé dans ladite cuve d'affinage pour assurer la désilicatisation et la déphosphoration consécutive de ladite fonte en gueuse, le procédé étant caractérisé:
a) par le chargement d'un réfrigérant conjointement avec ladite fonte en gueuse dans ladite cuve d'affinage afin de contrôler une température de ladite fonte en gueuse durant le soufflage sur une gamme de 1.250-1.450°C;
b) par le soufflage dudit agent affinant pulvérulent dans ladite fonte en gueuse de façon à régler une valeur de basicité de laitier après le traitement no inférieure à 2,5; et
c) par le soufflage dudit gaz de soufflage à un taux non inférieur à 0,5 Nm 3/mn par tonne de fonte en gueuse de façon que la quantité d'oxygène nette soit 8-15 Nm3 par tonne de fonte en gueuse.
2. Procédé selon la revendication 1, caractérisé en ce que le réfrigérant est au minimum un matériau sélectionné à partir de minerai de fer, de minerai de manganèse, de calamine, et de déchets de laminoirs.
3. Procédé selon la revendication 1 ou 2 caractérisé en ce que l'agent affinant pulvérulent est au minimum composé d'oxyde de calcium et de carbonate de calcium.
4. Procédé selon une quelconque des revendications précédentes, caractérisé en ce que le fondant est au minimum un matériau sélectionné à partir de spath de fluor, de soude calcinee, de cryolité, de colémanite et de boue rouge.
5. Procédé selon une quelconque des revendications précédentes, caractérisé en ce que l'agent affinant pulvérulent est chargé dans une quantité non inférieure à 12 kg par tonne de fonte en gueuse, et/ou en ce que le fondant est chargé dans une quantité non inférieure à 2 kg par tonne de fonte en gueuse.
6. Procédé selon une quelconque des revendications précédentes caractérisé en ce que le condant est chargé sur la fonte en gueuse à partir du haut de la dite cuve d'affinage.
7. Procédé selon une quelconque des revendications 1 à 5, caractérisé en ce que le fondant est mélangé avec ledit agent affinant pulvérulent et soufflé dans la fonte en gueuse conjointement avec ledit gaz de soufflage par lesdites tuyères.
8. Procédé selon une quelconque des revendications 1 a 5, caractérisé en ce que le fondant est simultanément chargé à partir du haut de ladite cuve d'affinage et par le dites tuyères au fond de la dite cuve d'affinage.
9. Procédé selon une quelconque des revendications précédentes, caractérisé en ce que la cuve d'affinage est un convertisseur à soufflerie de fond.
10. Procédé selon une quelconque des revendications 1 à 8 caractérisé en ce que la cuve d'affinage est un convertisseur à soufflerie de dessus et de fond.
EP19810302859 1980-06-28 1981-06-25 Procédé de déphosphoration d'un bain de fonte Expired EP0043238B1 (fr)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP88081/80 1980-06-28
JP8808180A JPS5713110A (en) 1980-06-28 1980-06-28 Dephosphorization treatment of molten iron
JP20830/81 1981-02-17
JP2083081A JPS57137408A (en) 1981-02-17 1981-02-17 Dephosphorization treatment of molten iron
JP7472081A JPS57192210A (en) 1981-05-18 1981-05-18 Dephosphorization of low-silicon pig iron
JP74720/81 1981-05-18

Publications (2)

Publication Number Publication Date
EP0043238A1 EP0043238A1 (fr) 1982-01-06
EP0043238B1 true EP0043238B1 (fr) 1984-10-10

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AU (1) AU529793B2 (fr)
DE (1) DE3166581D1 (fr)

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Publication number Priority date Publication date Assignee Title
JPH0297611A (ja) * 1988-09-30 1990-04-10 Nippon Steel Corp 冷鉄源溶解方法
CN1046139C (zh) * 1997-10-08 1999-11-03 冶金工业部钢铁研究总院 铁水预脱磷方法
JP3940280B2 (ja) * 2001-09-27 2007-07-04 新日本製鐵株式会社 溶銑の脱りん方法
CN103725825A (zh) * 2014-01-24 2014-04-16 安徽工业大学 一种以铝工业赤泥为基体的转炉炼钢脱磷剂及其制备方法
CN109852762A (zh) * 2019-04-01 2019-06-07 山东钢铁集团日照有限公司 一种复合型顶底复吹转炉底喷石灰石冶炼方法
CN113355487A (zh) * 2021-06-07 2021-09-07 张准 一种无镁矿相重构剂及制备方法和转炉炼钢造渣方法

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR986779A (fr) * 1949-03-18 1951-08-06 Commentry Fourchambault Et Dec Procédé de déphosphoration de la fonte et fonte obtenue
FR1062328A (fr) * 1951-08-30 1954-04-21 Procédé pour la déphosphoration de métaux, par exemple de la fonte et ins?ons pour la mise en oeuvre de ce procédé
DE1275078B (de) * 1958-11-03 1968-08-14 Mannesmann Ag Verfahren zum Herstellen von phosphorarmem Stahl aus phosphorhaltigem Roheisen, insbesondere Thomasroheisen
GB1043228A (en) * 1963-02-07 1966-09-21 Stora Kopparbergs Bergslags Ab Process for the manufacture of low phosphorous pig iron
DE1433649A1 (de) * 1964-03-03 1969-05-14 Thyssen Huette Ag Verfahren zum Entphosphoren von Roheisen,insbesondere Thomasroheisen
LU62943A1 (fr) * 1971-04-07 1973-05-16
FR2146969A1 (en) * 1971-07-29 1973-03-09 Creusot Loire Feeding pulverulent, materials to a melt - in a converter using double coaxial tuyeres
US4065297A (en) * 1976-09-28 1977-12-27 Sumitomo Metal Industries Limited Process for dephosphorizing molten pig iron

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DE3166581D1 (en) 1984-11-15
AU7234581A (en) 1982-04-01
EP0043238A1 (fr) 1982-01-06
AU529793B2 (en) 1983-06-23

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