JPS6321724B2 - - Google Patents
Info
- Publication number
- JPS6321724B2 JPS6321724B2 JP57213618A JP21361882A JPS6321724B2 JP S6321724 B2 JPS6321724 B2 JP S6321724B2 JP 57213618 A JP57213618 A JP 57213618A JP 21361882 A JP21361882 A JP 21361882A JP S6321724 B2 JPS6321724 B2 JP S6321724B2
- Authority
- JP
- Japan
- Prior art keywords
- decarburization
- refining
- steel
- slag
- decarburizing
- 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
Links
- 229910000831 Steel Inorganic materials 0.000 claims description 45
- 239000010959 steel Substances 0.000 claims description 45
- 238000005261 decarburization Methods 0.000 claims description 44
- 238000000034 method Methods 0.000 claims description 33
- 238000007664 blowing Methods 0.000 claims description 30
- 238000007670 refining Methods 0.000 claims description 27
- 239000002893 slag Substances 0.000 claims description 23
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 19
- 239000001301 oxygen Substances 0.000 claims description 19
- 229910052760 oxygen Inorganic materials 0.000 claims description 19
- 238000010907 mechanical stirring Methods 0.000 claims description 17
- 238000003756 stirring Methods 0.000 claims description 16
- 239000007787 solid Substances 0.000 claims description 14
- 230000009467 reduction Effects 0.000 claims description 8
- 239000003638 chemical reducing agent Substances 0.000 claims description 4
- 239000003795 chemical substances by application Substances 0.000 claims description 4
- 230000003009 desulfurizing effect Effects 0.000 claims 1
- 239000007789 gas Substances 0.000 description 21
- 239000011651 chromium Substances 0.000 description 9
- 230000008901 benefit Effects 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 6
- 238000013019 agitation Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 229910001220 stainless steel Inorganic materials 0.000 description 5
- 239000010935 stainless steel Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000007654 immersion Methods 0.000 description 4
- 239000003245 coal Substances 0.000 description 3
- 239000011261 inert gas Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 229910017082 Fe-Si Inorganic materials 0.000 description 2
- 229910017133 Fe—Si Inorganic materials 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 239000011819 refractory material Substances 0.000 description 2
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 239000003610 charcoal Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 239000003085 diluting agent Substances 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
Classifications
-
- 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
- C21C5/32—Blowing from above
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Description
【発明の詳細な説明】
本発明は普通鋼、ステンレス鋼等の溶鋼の脱炭
精錬法に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for decarburizing and refining molten steel such as ordinary steel and stainless steel.
溶鋼の脱炭精錬炉は大別して第１図に示す如く
上吹き法ａ、上底吹複合吹錬法ｂ、及び鋼浴中に
浸漬した羽口から酸素を吹込む底吹き法ｃ−１又
はｃ−２の３種類に分類される。このうち普通鋼
に適用されているのが、ａ、ｂ、ｃ−１でステン
レス鋼ではｃ−２が盛んに用いられている。ｃ−
２は横吹き法とも呼ばれるが底吹法の一種であ
る。 As shown in Figure 1, molten steel decarburization refining furnaces are roughly divided into top blowing method a, top and bottom blowing combined blowing method b, and bottom blowing method c-1 in which oxygen is blown into the tuyeres immersed in the steel bath. It is classified into three types: c-2. Among these, a, b, and c-1 are applied to ordinary steel, and c-2 is widely used in stainless steel. c-
2 is also called the side blowing method, but it is a type of bottom blowing method.
これらはいずれも鋼浴上部から又は炉底部の浸
漬羽口から鋼浴内に気体酸素を吹込み脱炭をはか
つている。 In all of these, gaseous oxygen is blown into the steel bath from the top of the steel bath or from the immersion tuyeres at the bottom of the furnace to effect decarburization.
最近普通鋼の分野で底吹き法が見直され、これ
を併用した上底吹吹錬法が盛んになつて来てい
る。これは上吹法にくらべて底吹法の方が脱炭精
錬中の鋼浴の撹拌強度が第２図に示す如く強く、
スラグ中の酸化物（固体酸素）と鋼浴中の〔Ｃ〕
との反応が促進され、Fe及びMn等のメタル歩留
が向上するとともに脱〔Ｓ〕機能が著しく促進さ
れ多大の利点があるからである。しかし、上底吹
きの欠点は、炉底部に浸漬羽口を持つため、底吹
による撹拌強度アツプの必要のないときでも絶え
ずガスを流しつづけていなければならず、スラグ
の酸化度を高め（FeO、MnOに富むスラグをつ
くる）脱〔Ｐ〕機能を高めた脱炭精錬を行うこと
が出来ない。又底吹ガスには不活性ガスを用いる
ことが多いので、このガスコストもコストアツプ
の要因となつている。 Recently, the bottom blowing method has been reconsidered in the field of ordinary steel, and the top and bottom blowing method that uses this method in combination is becoming popular. This is because the stirring intensity of the steel bath during decarburization is stronger in the bottom blowing method than in the top blowing method, as shown in Figure 2.
Oxide (solid oxygen) in slag and [C] in steel bath
This is because the reaction with the metal is promoted, the yield of metals such as Fe and Mn is improved, and the [S] removal function is significantly promoted, resulting in many advantages. However, the disadvantage of top-bottom blowing is that it has immersed tuyeres at the bottom of the furnace, so gas must be kept flowing even when there is no need to increase the agitation intensity by bottom blowing, which increases the degree of oxidation of the slag (FeO , it is not possible to perform decarburization smelting with enhanced de[P] function (creating slag rich in MnO). Furthermore, since an inert gas is often used as the bottom blowing gas, the cost of this gas is also a factor in increasing costs.
本発明は、上底吹複合精錬法の欠点を排除し上
吹法の利点及び底吹法の利点を合せ持たせた脱炭
精錬法を提供するものである。 The present invention provides a decarburization refining method that eliminates the drawbacks of the top-bottom blowing combined refining method and combines the advantages of the top-blowing method and the bottom-blowing method.
すなわち、本発明は、気体酸素を脱炭精錬容器
内の鋼浴面に吹付けるか又は鋼浴中に吹込むこと
により、鋼浴中、スラグ中の一方又は双方に固体
酸化物を形成せしめた後、該鋼浴を機械撹拌する
ことにより該固体酸化物を酸素源として脱炭する
ことを特徴とする。 That is, the present invention forms solid oxides in one or both of the steel bath and slag by blowing gaseous oxygen onto the surface of the steel bath in the decarburization refining vessel or into the steel bath. Afterwards, the steel bath is mechanically stirred to decarburize the solid oxide using the solid oxide as an oxygen source.
脱炭精錬容器としては例えば底部に浸漬羽口を
持たない、シンプルな容器を用い、まず第１図ａ
の如く上吹き法により気体酸素を吹付けて脱炭を
行い、所定の脱炭反応を進行させ鋼浴中、スラグ
中の一方又は双方にFeO、MnO等の酸化物を形
成させた後に上吹ランスを旋回退避させ第３図ａ
に示す如く機械撹拌用のインペラー１を炉内に挿
入し、所定時間所定の強度で撹拌することにより
該固体酸化物を酸素源として脱炭精錬する。なお
対象鋼種が、スラグの酸化度の高いことを要求さ
れる鋼種、即ち高い脱〔Ｐ〕機能を要求されるも
のであれば上吹法のまま脱炭精錬を終了すればよ
いが、脱〔Ｐ〕機能を要求されず高いメタル歩留
と脱〔Ｓ〕率を要求される鋼種は本発明法によつ
て機械撹拌まで行う。 As a decarburization refining vessel, for example, a simple vessel without an immersion tuyere at the bottom is used, and first,
Decarburization is performed by blowing gaseous oxygen using the top blowing method, and after the specified decarburization reaction has progressed and oxides such as FeO and MnO are formed in one or both of the steel bath and slag, the top blowing method is used. Turn the lance and retreat.
As shown in the figure, an impeller 1 for mechanical stirring is inserted into the furnace, and the solid oxide is decarburized and refined by stirring at a predetermined intensity for a predetermined time, using the solid oxide as an oxygen source. Note that if the target steel is one that requires a high degree of slag oxidation, that is, a high de[P] function, then the decarburization refining can be completed using the top-blowing method; P] Steel types that do not require high metal yield and [S] removal rate are subjected to mechanical stirring by the method of the present invention.
機械撹拌の際、鋼浴中及びスラグ中に気体酸素
吹錬によつて生じている酸化物によつて鋼中
〔Ｃ〕が脱炭されるのであらかじめ最終〔Ｃ〕よ
りも鋼浴中及びスラグ中の酸素量に見合つた高い
〔Ｃ〕で上吹の吹止めを行えばよい。即ち本発明
法は、従来の底吹きガスによる鋼浴の撹拌に替え
て第３図ａに示す如く、機械撹拌によつてスラグ
と鋼浴間の反応を促進させてやるものである。ガ
ス撹拌と機械撹拌では、その撹拌強度が同じでも
（均一混合時間が同じでも）鋼浴とスラグの反応
性は圧倒的に機械撹拌の方が大である。その理由
は機械撹拌は鋼浴の渦流にスラグが捲込まれ、微
細化され分散浮上してくるものであり、酸素源で
ある固体酸素（酸化物）を保持するスラグの体積
は溶鋼に対して圧倒的に少ないので、このスラグ
の浸入・浮上の循環は数10回にも及ぶため、スラ
グ、鋼浴間の反応が著しく促進されるからであ
る。 During mechanical agitation, the [C] in the steel is decarburized by the oxides generated in the steel bath and slag by gaseous oxygen blowing, so that the content of the steel bath and slag is higher than the final [C]. It is sufficient to stop the top blowing at a high [C] commensurate with the amount of oxygen inside. That is, in the method of the present invention, the reaction between the slag and the steel bath is promoted by mechanical stirring, as shown in FIG. 3a, instead of the conventional stirring of the steel bath by bottom-blown gas. In gas stirring and mechanical stirring, even if the stirring intensity is the same (even if the uniform mixing time is the same), the reactivity of the steel bath and slag is overwhelmingly greater in mechanical stirring. The reason for this is that in mechanical agitation, slag is drawn into the vortex of the steel bath, becomes fine and dispersed, and the volume of slag that holds solid oxygen (oxide), which is an oxygen source, is smaller than that of molten steel. This is because the amount of slag is so small that the cycle of slag infiltration and floating takes place several dozen times, which significantly accelerates the reaction between the slag and the steel bath.
これに対して、ガス撹拌ではガスが鋼浴を抜け
るときに溶鋼の飛沫がスラグ上部に飛び出し、ス
ラグ層を通して落下してくるので、圧倒的に体積
の多い溶鋼がスラグ中を通過するため循環度数は
極めて少ない。このために第４図に示す如く、機
械撹拌における脱炭速度はガス撹拌におけるより
も大気圧及び減圧下いずれの状態においても速い
結果となる。 On the other hand, with gas agitation, when the gas passes through the steel bath, droplets of molten steel fly out to the top of the slag and fall through the slag layer, so the molten steel, which has an overwhelmingly large volume, passes through the slag, increasing the circulation rate. are extremely rare. For this reason, as shown in FIG. 4, the decarburization rate in mechanical stirring is faster than that in gas stirring under both atmospheric pressure and reduced pressure.
又スラグの酸化度の調整はインペラーの回転数
及び撹拌時間で任意に制御可能である。 Further, the degree of oxidation of the slag can be arbitrarily controlled by adjusting the rotation speed of the impeller and the stirring time.
このように機械撹拌を導入することにより、絶
えず鋼浴に浸漬されている羽口が不用となるため
炉体の管理が容易となり、炉体寿命を従来の上吹
法のみの場合に近いレベルとすることが可能とな
り同時に底吹きのガスが不用となり、耐火物及び
ガスコストの大幅な削減が可能となるものであ
る。 Introducing mechanical stirring in this way eliminates the need for tuyeres that are constantly immersed in the steel bath, making furnace management easier and extending the lifespan of the furnace to a level close to that of the conventional top-blowing method. At the same time, bottom-blown gas is no longer required, and the cost of refractories and gas can be significantly reduced.
次にステンレス鋼に適用した場合の例について
述べる。ステンレス鋼における脱炭機構のメカニ
ズムは、
O2＋〔Cr〕→Cr2O3 (1)
Cr2O3＋〔Ｃ〕→〔Cr〕＋CO↑ (2)
(1)及び(2)式のくりかえしであると考えられてい
る。 Next, an example of application to stainless steel will be described. The decarburization mechanism in stainless steel is O 2 + [Cr] → Cr 2 O 3 (1) Cr 2 O 3 + [C] → [Cr] + CO↑ (2) Equations (1) and (2) It is believed to be repeated.
(1)式の左辺のO2は浸漬羽口より吹込まれる気
体酸素であり、(2)式の左辺の〔Ｃ〕は鋼中の
〔Ｃ〕である。この(1)及び(2)式から判る如く、脱
炭はCr2O3又はFeO、MnO等他の固体酸化物を介
して行われているものである。脱炭反応の律速は
(2)式であり、この反応を促進させるために従来は
希釈ガスを用いたり（AOD法）、又は減圧を行つ
たり（真空脱炭）してCOガスの分圧Pcpの低下を
はかつている。しかし如何にPcpの低下をはかろ
うとも、Cr2O3等の酸化物と鋼中〔Ｃ〕が出合
い、衝突しなければ脱炭を生じない。この出合、
衝突を行わせるために炉底部よりガスを吹込み、
強力な撹拌状態をつくり出している。しかし、減
圧を行い脱炭する方法はこの撹拌力として底吹き
ガスを用いているが、撹拌力を強化するために多
量のガスを吹込めば、減圧の効果が減じられ、極
めて中途半端な状態となり、脱炭速度が著しく遅
くならざるを得ない状態である。 O 2 on the left side of equation (1) is gaseous oxygen blown in from the immersion tuyere, and [C] on the left side of equation (2) is [C] in the steel. As can be seen from these equations (1) and (2), decarburization is performed via Cr 2 O 3 or other solid oxides such as FeO and MnO. The rate-determining rate of the decarburization reaction is
Equation (2) is conventionally used to promote this reaction by using a diluent gas (AOD method) or reducing the pressure (vacuum decarburization) to reduce the partial pressure P cp of CO gas. There used to be. However, no matter how much efforts are made to lower P cp , decarburization will not occur unless oxides such as Cr 2 O 3 and [C] in the steel meet and collide. This encounter,
Gas is injected from the bottom of the furnace to cause collision.
Creates a strong stirring state. However, the method of decarburization by depressurization uses bottom-blown gas as the stirring force, but if a large amount of gas is blown in to strengthen the stirring force, the effect of pressure reduction is reduced, resulting in an extremely incomplete state. Therefore, the decarburization rate has to become extremely slow.
本発明をステンレス鋼に適用した１つの例につ
いて述べると、第一段階としては、前記と同様底
部に浸漬羽口を持たない簡単な脱炭容器を用い
て、第１図ａの如く上吹き脱炭を行なう。この間
鋼中及びスラグ中に固体酸化物Cr2O3、FeO、
MnO等が脱炭酸素効率の大小に応じて形成され
る。この酸化物が、次のステツプである機械撹拌
による強力な撹拌によつてある脱炭効率を以つ
て、鋼中〔Ｃ〕の脱炭に寄与することになる。従
つて最終〔Ｃ〕までの脱炭に必要な、鋼浴中及び
スラグ中の酸化物が生成される迄上吹吹錬によつ
て脱炭を行う。 To describe one example in which the present invention is applied to stainless steel, the first step is to use a simple decarburization container that does not have an immersion tuyere at the bottom as described above, and use a top-blown decarburization container as shown in Figure 1a. Do charcoal. During this period, solid oxides Cr 2 O 3 , FeO,
MnO etc. are formed depending on the degree of decarburization oxygen efficiency. This oxide contributes to the decarburization of [C] in the steel with a certain decarburization efficiency through the next step of powerful mechanical stirring. Therefore, decarburization is carried out by top blowing until the oxides in the steel bath and slag necessary for decarburization to the final stage [C] are produced.
次にランスを引き上げ、旋回退避させ、第２段
階として第３図ａのように撹拌インペラー１を脱
炭精錬容器４内に挿入し、機械撹拌を行う。これ
により、すでに述べた如くガス撹拌よりもスラグ
と鋼浴〔Ｃ〕との出合、衝突の機会は著しく増大
するため、Pcpを希釈することなくしても〔Ｃ〕
量0.08〜0.06％の低炭域まで容易に脱炭すること
ができる。同時に気体酸素吹込によつて生じた酸
化物が鋼中〔Ｃ〕で還元される率が従来の方法
（例えばAOD）よりも高いために引続く還元精錬
工程での還元剤及び造滓剤の使用量の低減が可能
であり、この点からも本発明の利点は大きい。 Next, the lance is pulled up and turned to retreat, and in the second step, the stirring impeller 1 is inserted into the decarburization refining vessel 4 as shown in FIG. 3a, and mechanical stirring is performed. As a result, as mentioned above, the chances of the slag and steel bath [C] meeting and colliding with each other are significantly increased compared to gas agitation, so even without diluting P cp , [C]
It can be easily decarburized to a low coal content range of 0.08 to 0.06%. At the same time, since the rate at which oxides generated by gaseous oxygen injection are reduced in [C] in steel is higher than in conventional methods (e.g. AOD), reducing agents and slag-forming agents are used in the subsequent reduction refining process. The amount can be reduced, and the present invention has a great advantage from this point as well.
又第２段階として第３図ｂに示す如く排気口２
から排気し脱炭精錬容器４内を減圧し減圧脱炭と
併用すると、炉底より撹拌ガスを吹込まないので
減圧の効果を減ずることなく強力な撹拌が得られ
るために脱炭速度が極めて早く生産性、耐火物、
ガスコストの上で大きな利点がある。 In addition, as a second step, the exhaust port 2 is opened as shown in Figure 3b.
When used in combination with vacuum decarburization by exhausting air from the furnace and reducing the pressure inside the decarburization refining vessel 4, the decarburization speed is extremely fast because stirring gas is not blown in from the bottom of the furnace, and strong stirring can be obtained without reducing the effect of pressure reduction. productivity, refractories,
There is a big advantage in terms of gas costs.
又機械撹拌脱炭中に固体酸素源が不足する場合
には随時Fe2O3、NiO、Cr2O3等の固体酸化物を
投入すればよい。 Furthermore, if a solid oxygen source is insufficient during mechanical stirring decarburization, a solid oxide such as Fe 2 O 3 , NiO, Cr 2 O 3 or the like may be added as needed.
このように、高炭域においては上吹酸素吹錬を
行つて固体酸素源を形成せしめ、中、低炭域にお
いては機械撹拌による脱炭を行うことにより、従
来ガスを吹込んでいた炉底部の羽口が不用とな
り、炉体煉亙の管理が著しく容易となるとともに
炉体寿命も飛躍的に増大するものである。又撹拌
用の不活性ガスが大幅に削減される。同時に減圧
脱炭と併用すればその生産性は著しく向上し、多
大の利益をもたらすものである。 In this way, in the high coal region, top-blown oxygen blowing is performed to form a solid oxygen source, and in the medium and low coal regions, decarburization is performed by mechanical stirring. Tuyeres are no longer required, making the management of the furnace body much easier, and the lifespan of the furnace body is also dramatically increased. Also, the amount of inert gas used for stirring is significantly reduced. If it is used in combination with vacuum decarburization, the productivity will be significantly improved, bringing great benefits.
以上の説明からも判る如く、この機械撹拌脱炭
及び精錬は同一の炉内で行う必要は全くない。例
えばAOD法により底吹吹錬により効率よく所定
の〔Ｃ〕迄脱炭を行い、直ちに脱炭精錬容器とし
て第３図ｄに示す取鍋５に出鋼しこの取鍋内にイ
ンペラーを挿入し機械撹拌脱炭、精錬を行うこと
もでき、極めて有効である。また第３図ｅのよう
に取鍋５内を減圧すれば第３図ｂと同様の効果が
得られる。 As can be seen from the above explanation, there is no need to perform this mechanical stirring decarburization and refining in the same furnace. For example, the AOD method is used to efficiently decarburize to a predetermined [C] by bottom blowing, and then the steel is immediately tapped into a ladle 5 shown in Figure 3d as a decarburization refining vessel, and an impeller is inserted into this ladle. Mechanical stirring decarburization and refining can also be performed and are extremely effective. Further, if the pressure inside the ladle 5 is reduced as shown in FIG. 3e, the same effect as shown in FIG. 3b can be obtained.
尚、Pcpを低減させるために、第３図ｃに示す
如く浸漬したインペラー１の先端３より、該イン
ペラーの冷却を兼ねて不活性ガスを吹込むことは
一層脱炭を容易にするものである。 In addition, in order to reduce P cp , blowing inert gas through the tip 3 of the impeller 1 which is immersed as shown in Fig. 3c for the purpose of cooling the impeller further facilitates decarburization. be.
更に脱炭に引続く還元精錬においても、本機械
撹拌は極めて有効である。即ち還元剤（Fe−Si
等）及び造滓剤を添加し、機械撹拌を行えば、す
でに述べた如くスラグ・鋼浴間の強力な撹拌が生
じ非常に短時間に還元精錬（還元・脱〔Ｓ〕）を
行うことが出来るものである。しかもすでに述べ
た如く機械撹拌脱炭を行つているために、スラグ
中あるいは鋼浴中の酸化物は脱炭に寄与し通常の
精錬時よりも著しく減少しているので、有価元素
であるクロムの還元に用いられる還元剤Fe−Si
及び造滓剤CaO、CaF2は従来よりも少なくてす
むという利点を生じる。 Furthermore, this mechanical stirring is extremely effective in reduction refining following decarburization. That is, reducing agent (Fe-Si
If a slag-forming agent (e.g., It is possible. Moreover, as mentioned above, since mechanical stirring decarburization is performed, the oxides in the slag or steel bath contribute to decarburization and are significantly reduced compared to during normal refining, so that the valuable element chromium is removed. Reducing agent Fe-Si used for reduction
The advantage is that the amount of sludge-forming agents CaO and CaF 2 can be reduced compared to conventional methods.
以上の如く還元精錬時に用いても、時間の短縮
及びガスが全く不要であるからガスコストの低減
等多大の利益をもたらすものである。 As described above, even when used during reduction refining, it brings about great benefits such as reduction in time and gas cost since it does not require any gas at all.
以上のごとく本発明の脱炭精錬法は工業的に多
大の利益をもたらす有効な発明である。 As described above, the decarburization refining method of the present invention is an effective invention that brings great industrial benefits.
第１図は従来の脱炭精錬法を示す図、第２図は
従来の脱炭精錬法における撹拌能力におよぼす底
吹ガス比率の影響を示す図、第３図は本発明法に
おける機械撹拌手段を示す図、第４図は本発明の
効果を示す図である。
Figure 1 is a diagram showing the conventional decarburization refining method, Figure 2 is a diagram showing the influence of the bottom blowing gas ratio on the stirring capacity in the conventional decarburization refining method, and Figure 3 is a diagram showing the mechanical stirring means in the method of the present invention. FIG. 4 is a diagram showing the effects of the present invention.
Claims (1)
るか又は鋼浴中に吹込むことにより、鋼浴中、ス
ラグ中の一方又は双方に固体酸化物を形成せしめ
た後、該鋼浴を機械撹拌することにより該固体酸
化物を酸素源として脱炭することを特徴とする溶
鋼の脱炭精錬法。 ２ 脱炭精錬容器内を減圧して機械撹拌すること
を特徴とする特許請求の範囲第１項記載の溶鋼の
脱炭精錬法。 ３ 脱炭精錬容器として取鍋を用いて機械撹拌す
ることを特徴とする特許請求の範囲第１項又は第
２項記載の溶鋼の脱炭精錬法。 ４ 脱炭終了後に還元剤及び脱硫剤を添加し機械
撹拌して、還元精錬することを特徴とする特許請
求の範囲第１項ないし第３項の何れかに記載の溶
鋼の脱炭精錬法。[Claims] 1. Solid oxides are formed in one or both of the steel bath and slag by blowing gaseous oxygen onto the surface of the steel bath in the decarburization refining vessel or into the steel bath. A decarburizing refining method for molten steel, which comprises decarburizing the solid oxide as an oxygen source by mechanically stirring the steel bath. 2. The method for decarburizing and refining molten steel according to claim 1, characterized in that the inside of the decarburizing refining vessel is depressurized and mechanically stirred. 3. A method for decarburizing and refining molten steel according to claim 1 or 2, characterized in that mechanical stirring is carried out using a ladle as a decarburizing refining vessel. 4. The method for decarburizing and refining molten steel according to any one of claims 1 to 3, characterized in that after the decarburization is completed, a reducing agent and a desulfurizing agent are added and mechanically stirred to perform reduction refining.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21361882A JPS59104422A (en) | 1982-12-06 | 1982-12-06 | Decarburization refining method of molten steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21361882A JPS59104422A (en) | 1982-12-06 | 1982-12-06 | Decarburization refining method of molten steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59104422A JPS59104422A (en) | 1984-06-16 |
| JPS6321724B2 true JPS6321724B2 (en) | 1988-05-09 |
Family
ID=16642151
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21361882A Granted JPS59104422A (en) | 1982-12-06 | 1982-12-06 | Decarburization refining method of molten steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59104422A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2538879B2 (en) * | 1986-06-04 | 1996-10-02 | 川崎製鉄株式会社 | Method for refining molten metal |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5333936A (en) * | 1976-07-21 | 1978-03-30 | Kuwan Shiyan Wai | Apparatus and process for electric decomposition treatment of metal plate |
| JPS5591926A (en) * | 1978-12-29 | 1980-07-11 | Nisshin Steel Co Ltd | Preparation of extremely low carbon nitrogen stainless steel |
-
1982
- 1982-12-06 JP JP21361882A patent/JPS59104422A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5333936A (en) * | 1976-07-21 | 1978-03-30 | Kuwan Shiyan Wai | Apparatus and process for electric decomposition treatment of metal plate |
| JPS5591926A (en) * | 1978-12-29 | 1980-07-11 | Nisshin Steel Co Ltd | Preparation of extremely low carbon nitrogen stainless steel |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59104422A (en) | 1984-06-16 |
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