JP3176679B2 - Converter scouring method - Google Patents
Converter scouring methodInfo
- Publication number
- JP3176679B2 JP3176679B2 JP01817192A JP1817192A JP3176679B2 JP 3176679 B2 JP3176679 B2 JP 3176679B2 JP 01817192 A JP01817192 A JP 01817192A JP 1817192 A JP1817192 A JP 1817192A JP 3176679 B2 JP3176679 B2 JP 3176679B2
- Authority
- JP
- Japan
- Prior art keywords
- converter
- blowing
- slag
- desulfurization
- reduction
- 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 - Fee Related
Links
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- Carbon Steel Or Casting Steel Manufacturing (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は複合吹錬転炉、いわゆる
上底吹き転炉で吹錬のさいに脱硫とマンガン鉱石の還元
を同時に効率よく行なう方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for simultaneously and efficiently performing desulfurization and reduction of manganese ore during blowing in a combined blowing converter, that is, a so-called top-bottom blowing converter.
【０００２】[0002]
【従来の技術】従来より鋼の脱硫は転炉吹錬中の酸化性
雰囲気では反応が期待できないために炉外精練によって
いた。すなわち、溶銑段階での脱硫処理、あるいは転炉
出鋼後の２次精練における溶鋼脱硫処理が行なわれてい
た。したがって、脱硫促進策としてはもっぱら溶銑脱硫
あるいは溶鋼脱硫における反応効率向上に力が入れられ
てきており、転炉吹錬における脱硫に関してはその取り
組みが全くなされてこなかった。2. Description of the Prior Art Conventionally, desulfurization of steel has been carried out by out-of-furnace scouring since no reaction can be expected in an oxidizing atmosphere during converter blowing. That is, the desulfurization treatment at the hot metal stage or the desulfurization treatment of the molten steel in the secondary refining after the start of the converter is performed. Therefore, as a desulfurization accelerating measure, much effort has been put into improving the reaction efficiency in hot metal desulfurization or molten steel desulfurization, and no attempt has been made for desulfurization in converter blowing.
【０００３】一方、溶銑脱燐技術の進歩と平行して転炉
レススラグ吹錬を利用したマンガン鉱石の溶融還元法が
開発され、その還元歩留向上のための努力がなされてい
るが、その改善手段は大気圧精練前提の中での攪拌強化
による（ＦｅＯ）低減策が代表的なものである。On the other hand, in parallel with the development of hot metal dephosphorization technology, a manganese ore smelting reduction method using converterless slag blowing has been developed, and efforts have been made to improve the reduction yield. As a means, a measure for reducing (FeO) by strengthening stirring under the premise of atmospheric pressure scouring is typical.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、脱硫に
ついては炉外精練によっているため必然的に工程が増
え、それによる設備費増、要員増、さらにはエネルギー
ロスによるコストアップの問題を不可避的にはらんでい
るため、有効なコストダウンにつながりにくかった。However, desulfurization involves in-furnace refining, so the number of processes is inevitably increased, which inevitably leads to increased equipment costs, increased personnel, and increased costs due to energy loss. Because of this, it was difficult to lead to effective cost reduction.
【０００５】また、転炉内におけるマンガン鉱石の溶融
還元においては大気圧精練を前提としていたために、攪
拌強化を徹底しても（ＦｅＯ）低減には限界があり、こ
れについても有効な改善手段が見いだしにくかった。し
たがってこれらの目的、すなわち脱硫とマンガン鉱石還
元を転炉だけで、しかも効率よく反応させるための手段
が強く望まれていた。[0005] Further, since smelting reduction of manganese ore in a converter is premised on atmospheric refining, there is a limit to the reduction of (FeO) even if thorough stirring is strengthened. Was difficult to find. Therefore, there has been a strong demand for a means for efficiently reacting these objects, that is, desulfurization and manganese ore reduction only with a converter.
【０００６】[0006]
【課題を解決するための手段】本発明は上記課題を解決
するものであって、溶銑予備処理にて脱燐処理を施した
溶銑を複合吹錬転炉で脱炭しながらマンガン鉱石を投入
して還元するさい、吹錬末期にスラグ排滓を施すこと無
く底吹きガスの流量を０．１Ｎｍ3 ／ｍｉｎ・ｔ以上で
攪拌しつつ、転炉内を４００Ｔｏｒｒ以下に減圧して、
スラグのＣａＯ／ＳｉＯ2 を２．５以上に調整すること
により、溶鋼の脱硫促進とマンガン鉱石の還元を効率よ
く行なうことを特徴とする転炉の精練方法である。SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to supply manganese ore while decarburizing hot metal that has been dephosphorized in hot metal pretreatment in a combined blowing converter. At the end of blowing, the inside of the converter was depressurized to 400 Torr or less while stirring the flow rate of the bottom blown gas at 0.1 Nm 3 / min · t or more without performing slag discharge at the end of blowing.
This is a refining method for a converter, wherein the desulfurization of molten steel and the reduction of manganese ore are efficiently performed by adjusting the CaO / SiO 2 of the slag to 2.5 or more.
【０００７】[0007]
【作用】本発明者らは、転炉内の脱硫とマンガン鉱石還
元を同時に促進する方法として、転炉吹錬末期の炉内を
減圧状態にすることを考えた。すなわち、ＣＯ分圧１気
圧での［Ｃ］−［Ｏ］平衡で規定された現状の吹止条件
（［Ｏ］、（ＦｅＯ））に対し、炉内を減圧にしてＣＯ
分圧を１より小さな値に制御した場合には、平衡論的に
現吹止条件より同一［Ｃ］における鋼中［Ｏ］とスラグ
中（ＦｅＯ）がいずれも減少することを利用するもので
ある。鋼中［Ｏ］とスラグ中（ＦｅＯ）が低減すれば還
元反応である脱硫とマンガン鉱石還元の同時促進が期待
できる。The present inventors have conceived a method of simultaneously promoting desulfurization and reduction of manganese ore in the converter by reducing the pressure in the furnace at the end of the converter blowing. That is, with respect to the current blowing conditions ([O], (FeO)) defined by the [C]-[O] equilibrium at a CO partial pressure of 1 atm, the pressure in the furnace is reduced and CO
When the partial pressure is controlled to a value smaller than 1, the fact that both [O] in steel and (FeO) in slag in the same [C] are reduced equilibrium theory from the current blow-off condition is used. is there. If [O] in steel and (FeO) in slag are reduced, simultaneous promotion of desulfurization and reduction of manganese ore, which are reduction reactions, can be expected.
【０００８】そこで、転炉吹錬末期条件における炉内圧
力とスラグの（ＦｅＯ）濃度の関係および脱硫率、マン
ガン鉱石還元率との関係について種々実験を重ねた結
果、図１に底吹ガス量０．１５Ｎｍ3 ／ｍｉｎ・ｔ、吹
止［Ｃ］：０．０８〜０．１％、ＣａＯ／ＳｉＯ2 ：
３．０〜３．３の場合についてその例を示すように炉内
圧力の低減の程度に応じてスラグ中の（ＦｅＯ）が低下
し、それに伴って脱硫率が向上し、マンガン鉱石の還元
率も向上することが判明した。特に４００Ｔｏｒｒ以下
でその効果が急増する。なお、これらのデータにおける
（ＦｅＯ）はスラグ中の全鉄量からこれがすべてＦｅＯ
になっているとして求めた値である（以下も同様）。[0008] Therefore, as a result of repeated experiments on the relationship between the furnace pressure and the slag (FeO) concentration, the desulfurization rate, and the manganese ore reduction rate under the last stage conditions of the converter blowing, FIG. 0.15 Nm 3 / min · t, blow stop [C]: 0.08 to 0.1%, CaO / SiO 2 :
As shown in the example in the case of 3.0 to 3.3, the (FeO) in the slag decreases according to the degree of reduction of the furnace pressure, the desulfurization rate increases accordingly, and the reduction rate of the manganese ore decreases. It was also found to improve. In particular, the effect rapidly increases at 400 Torr or less. Note that (FeO) in these data is based on the total amount of iron in the slag.
(The same applies to the following).
【０００９】脱硫およびマンガン鉱石還元の反応効率を
向上せしめる理由は上記したようにスラグ中の（Ｆｅ
Ｏ）の低減にあるが、これは以下のように解釈される。
すなわち、転炉内で起こる脱炭反応は、（１）式で示さ
れる。The reason for improving the reaction efficiency of desulfurization and manganese ore reduction is that (Fe
O), which is interpreted as follows.
That is, the decarburization reaction occurring in the converter is represented by the equation (1).
【００１０】 ［Ｃ］＋［Ｏ］＝ＣＯ（ｇ）・・・・・・・・・・・・（１） [C] + [O] = CO (g) (1)
【００１１】ここで、（１）式の平衡定数Ｋ1 は、炉内
ＣＯ分圧をｐco、（１）式の標準自由エネルギー変化を
△Ｇ0 coとすると数１で示される。なお鋼中［Ｃ］、
［Ｏ］は活量に代えて近似的に用いている（数２におい
ても同様）。[0011] Here, (1) the equilibrium constant K 1 of the formula, p co furnace CO partial pressure, indicated by the number 1 When (1) the standard free energy change △ G 0 co of. In addition, [C] in steel,
[O] is approximately used instead of the activity (the same applies to Expression 2).
【００１２】[0012]
【数１】 (Equation 1)
【００１３】数１からわかるように、平衡定数Ｋ1 は一
定温度の下では一定となる。したがつて、炉内圧力を低
減することは、ｐcoを低減することであるので、Ｋ1 お
よび［Ｃ］一定の条件から［Ｏ］を低下せしめることが
できる。一方、スラグ中（ＦｅＯ）は溶鋼Ｆｅと溶鋼中
の［Ｏ］との間で（２）式の平衡が成立する。As can be seen from Equation 1, the equilibrium constant K 1 is constant at a constant temperature. Therefore, since reducing the furnace pressure means reducing p co , it is possible to lower [O] from K 1 and [C] under certain conditions. On the other hand, in the slag (FeO), the equilibrium of the equation (2) is established between the molten steel Fe and [O] in the molten steel.
【００１４】 （ＦｅＯ）＝Ｆｅ＋［Ｏ］・・・・・・・・・・・・・（２） (FeO) = Fe + [O] (2)
【００１５】ここで（２）式の平衡定数Ｋ2 はスラグ中
ＦｅＯ活量をａFeO 、（２）式の標準自由エネルギー変
化を△Ｇ0 FeO とすると数２で示される。したがってス
ラグ中（ＦｅＯ）は［Ｏ］の低減とともに低減する。Here, the equilibrium constant K 2 in the equation (2) is represented by the following equation (2), where a FeO activity in the slag is a FeO and the standard free energy change in the equation (2) is ΔG 0 FeO . Therefore, (FeO) in the slag decreases as [O] decreases.
【００１６】[0016]
【数２】 (Equation 2)
【００１７】このように、転炉吹錬末期を減圧にするこ
とにより、鋼中［Ｏ］と（ＦｅＯ）の低減が図られるた
め、還元反応である脱硫とマンガン鉱石還元反応を促進
することができる。[0017] As described above, by reducing the pressure in the last stage of the converter blowing, [O] and (FeO) in the steel are reduced, so that the desulfurization and manganese ore reduction reactions, which are reduction reactions, can be promoted. it can.
【００１８】図１の実験は、小型上底吹き転炉による結
果であり、底吹き攪拌を０．１５Ｎｍ3 ／ｍｉｎ・ｔ一
定、スラグのＣａＯ／ＳｉＯ2 を３．０〜３．３のほぼ
一定の条件の下で行なったが、本発明者らは、更に底吹
き攪拌力あるいはＣａＯ／ＳｉＯ2 を種々変化させて実
験した。すなわち、減圧による（ＦｅＯ）の低減効果は
基本的に得られるが、より平衡に近い濃度まで（Ｆｅ
Ｏ）を低減するためには当然底吹き攪拌力が大きい方が
有利である。また脱硫反応、マンガン還元反応のいずれ
もスラグのＣａＯ／ＳｉＯ2 が大きいほど有利であり、
スラグ組成の制御が重要な操作要因になるためである。The experiment in FIG. 1 is a result of a small top-bottom blow converter, in which bottom blow stirring is constant at 0.15 Nm 3 / min · t and CaO / SiO 2 of slag is 3.0 to 3.3. Although the experiment was carried out under a certain condition, the present inventors conducted experiments by further changing the bottom blowing agitation force or the CaO / SiO 2 variously. That is, although the effect of reducing (FeO) by the reduced pressure is basically obtained, the concentration of (FeO) is reduced to a concentration closer to equilibrium.
In order to reduce O), it is naturally advantageous to have a large bottom-blowing stirring force. In addition, both desulfurization reaction and manganese reduction reaction are more advantageous as CaO / SiO 2 of the slag is larger,
This is because control of the slag composition is an important operation factor.
【００１９】図２は炉内圧力を２００Ｔｏｒｒ一定、吹
止［Ｃ］：０．０８〜０．１１％、スラグのＣａＯ／Ｓ
ｉＯ2 ：３．１〜３．４のほぼ一定条件で底吹き攪拌力
を変えた実験の結果を示している。図からわかるように
脱炭最盛期以降の吹錬末期における底吹き攪拌力が０．
１Ｎｍ3 ／ｍｉｎ・ｔより小さくなると、（ＦｅＯ）が
十分に低減せずに脱硫およびマンガン鉱石還元が十分に
は進行しない。したがって、減圧の効果を享受するには
０．１Ｎｍ3 ／ｍｉｎ・ｔ以上の攪拌力が必要である。FIG. 2 shows that the pressure in the furnace is constant at 200 Torr, blow stop [C]: 0.08 to 0.11%, CaO / S of slag.
The results of an experiment in which the bottom blowing agitation force was changed under almost constant conditions of iO 2 : 3.1 to 3.4 are shown. As can be seen from the figure, the bottom-blowing agitating power at the end of the blowing period after the peak period of decarburization is 0.
If it is less than 1 Nm 3 / min · t, desulfurization and manganese ore reduction will not proceed sufficiently without sufficiently reducing (FeO). Therefore, in order to enjoy the effect of reduced pressure, a stirring force of 0.1 Nm 3 / min · t or more is required.
【００２０】つぎに、吹止［Ｃ］：０．０８〜０．１１
％で炉内圧力を２００Ｔｏｒｒ一定、底吹き攪拌力を
０．１５Ｎｍ3 ／ｍｉｎ・ｔ一定としてスラグのＣａＯ
／ＳｉＯ2 を変えた実験の結果を図３に示す。図から明
らかなとおりスラグのＣａＯ／ＳｉＯ2 が２．５より低
い領域では脱硫、マンガン鉱石還元のいずれも反応の進
行が十分ではない。これは脱硫についてはＣａＯ／Ｓｉ
Ｏ2 が大きいほどスラグのＣａＯの活量が増大して、
（３）式の反応が促進するし、マンガン鉱石還元反応は
ＣａＯ／ＳｉＯ2 が大きいほど平衡Ｍｎ分配比（Ｍｎ）
／［Ｍｎ］が小さくなって還元が促進されるためであ
る。Next, blow stop [C]: 0.08 to 0.11
%, The furnace pressure is constant at 200 Torr, and the bottom blowing agitation force is constant at 0.15 Nm 3 / min · t.
FIG. 3 shows the results of the experiment in which / SiO 2 was changed. As is clear from the figure, in the region where CaO / SiO 2 of the slag is lower than 2.5, neither desulfurization nor reduction of manganese ore proceeds sufficiently. This is CaO / Si for desulfurization.
As O 2 is larger, the activity of CaO in the slag increases,
The reaction of the formula (3) is accelerated, and the manganese ore reduction reaction becomes more equilibrium Mn distribution ratio (Mn) as CaO / SiO 2 becomes larger.
/ [Mn] is reduced to promote reduction.
【００２１】 （ＣａＯ）＋［Ｓ］＝（ＣａＳ）＋［Ｏ］・・・・・・・・（３） (CaO) + [S] = (CaS) + [O] (3)
【００２２】なお、減圧と攪拌力の必要条件を与える時
期として、転炉吹錬末期と規定したが、具体的には、脱
炭最盛期が終わり脱炭速度が低下し始めるいわゆるＣB
点以降をその対象とする。なぜなら、ＣB より高［Ｃ］
領域では供給された酸素の全てが［Ｃ］と反応するた
め、減圧によって脱炭促進する意味をなさないし、たと
えこの領域に適用したことを想定しても多量のガスの膨
張により操業が極めて困難となることが予想され、現実
的ではない。The time when the necessary conditions of the pressure reduction and the stirring force are given is defined as the last stage of the converter blowing. Specifically, the so-called C B, in which the peak period of decarburization ends and the decarburization speed starts to decrease.
After that point is the target. Because higher than C B [C]
Since all of the supplied oxygen reacts with [C] in the region, it does not make sense to promote decarburization by reducing the pressure, and even if it is applied to this region, the operation is extremely difficult due to the expansion of a large amount of gas. Is not realistic.
【００２３】また、本発明を、溶銑予備処理にて脱燐し
た溶銑に対象を限った理由は、脱燐しない溶銑に本発明
を適用した場合、前述したようにスラグの（ＦｅＯ）が
通常吹錬より遥かに低くなるために脱燐が不可能になる
ことによる。したがって、本発明は、溶銑脱燐技術を前
提として成立する新しい製錬方法を与えるものである。The reason why the present invention is limited to hot metal dephosphorized in hot metal pretreatment is that when the present invention is applied to hot metal that does not dephosphorize, as described above, (FeO) of slag is usually blown. Dephosphorization is impossible because it is much lower than smelting. Therefore, the present invention provides a new smelting method that is established on the premise of hot metal dephosphorization technology.
【００２４】本発明の方法を実施するためには転炉の炉
内を減圧する設備が必要である。図４（ａ）はその例を
示す転炉の断面図である。上吹きランス５と底吹き羽口
６を有する上底吹き転炉であるが、通常の廃ガス回収の
固定ダクト４と炉口との間にスライド式のフード３を設
け、通常の吹錬時には開けておくが減圧時にはこれを下
降させてシールするようになっている。図４（ｂ）はこ
の部分の拡大図である。In order to carry out the method of the present invention, equipment for depressurizing the inside of the converter is required. FIG. 4A is a sectional view of a converter showing the example. Although it is a top-bottom-blowing converter having an upper-blowing lance 5 and a bottom-blowing tuyere 6, a sliding-type hood 3 is provided between a fixed duct 4 for normal waste gas recovery and a furnace port. It is kept open, but when it is depressurized, it is lowered and sealed. FIG. 4B is an enlarged view of this part.
【００２５】一方、固定ダクト４の先では廃ガス回収装
置へ導かれるＯＧダクト７から減圧ダクト８が分岐して
おり、それぞれの入口にはＯＧダンパー１、減圧ダンパ
ー２が設けられている。通常の吹錬時にはＯＧダンパー
１を開、減圧ダンパー２を閉とし、減圧時にはそれぞれ
の開閉をこれと逆にする。減圧装置は一般の真空脱ガス
装置の場合と同様にスチームエジェクターやメカニカル
ブースターポンプが用いられる。On the other hand, at the end of the fixed duct 4, a pressure reducing duct 8 branches from the OG duct 7 which is led to the waste gas recovery device, and an OG damper 1 and a pressure reducing damper 2 are provided at their respective inlets. During normal blowing, the OG damper 1 is opened and the decompression damper 2 is closed. As the pressure reducing device, a steam ejector or a mechanical booster pump is used as in the case of a general vacuum degassing device.
【００２６】[0026]
【実施例】減圧装置を設けた３５０ｔの上底吹き転炉で
成分Ｃ：３．９０〜４．５０％、Ｓｉ：０．０１〜０．
０３％、Ｍｎ：０．２０〜０．３０％、Ｐ：０．０９〜
０．１１％、Ｓ：０．０２０〜０．０３０％の溶銑を吹
錬した。脱炭最盛期の終点（ＣB 点）までは、通常転炉
と同様に１気圧のもとで吹錬し、ＣB 点以降を減圧にし
て［Ｃ］＝０．０８〜０．１１％で吹止めた。また吹止
温度は１６２０〜１６６０℃とした。底吹き攪拌は、吹
錬開始から吹止まで一定のガス流量を流した。操業条件
と結果とをそれぞれ表１と表２に示す。EXAMPLE In a 350 t top-bottom blow converter equipped with a decompression device, component C: 3.90 to 4.50%, Si: 0.01 to 0.1%.
03%, Mn: 0.20 to 0.30%, P: 0.09 to
0.11%, S: 0.020 to 0.030% hot metal was blown. Decarburization to its peak endpoint (C B point), usually blowing under converter as well as 1 atm, and the subsequent C B point vacuum [C] = 0.08~0.11% I stopped it. The blow stop temperature was 1620 to 1660 ° C. In the bottom blow stirring, a constant gas flow rate was supplied from the start of blowing to the stop of blowing. The operating conditions and results are shown in Tables 1 and 2, respectively.
【００２７】[0027]
【表１】 [Table 1]
【００２８】[0028]
【表２】 [Table 2]
【００２９】比較例１は減圧工程がないもの、比較例２
は減圧の圧力が不足のもの、比較例３および４は底吹き
ガス流量が不足のもの、比較例５および６はスラグのＣ
ａＯ／ＳｉＯ2 が不足のものであるが、いずれも脱硫
率、Ｍｎ歩留が悪くなっている。Comparative Example 1 has no decompression step, Comparative Example 2
Indicates that the depressurizing pressure is insufficient, Comparative Examples 3 and 4 indicate that the bottom blowing gas flow rate is insufficient, and Comparative Examples 5 and 6 indicate that the slag C
Although aO / SiO 2 is insufficient, the desulfurization rate and Mn yield are all poor.
【００３０】[0030]
【発明の効果】本発明に従い溶銑予備処理で脱燐処理を
施した溶銑を減圧条件で攪拌力とスラグ組成を制御しつ
つ吹錬することにより、吹錬中の脱硫が著しく促進され
るとともに添加したマンガン鉱石の還元歩留も大きく向
上するため、低硫鋼の製造が容易になるとともにＦｅ−
Ｍｎ系合金の使用量削減に伴うコストメリットも得ら
れ、本発明がこの種の産業分野にもたらす効果は極めて
大きい。According to the present invention, the hot metal subjected to the dephosphorization treatment in the hot metal pretreatment according to the present invention is blown under reduced pressure conditions while controlling the stirring power and the slag composition, so that the desulfurization during blowing is remarkably accelerated and added. The reduction yield of the reduced manganese ore is greatly improved, so that the production of low-sulfur steel is facilitated and Fe-
There is also a cost advantage associated with the reduction in the amount of Mn-based alloy used, and the effect of the present invention in this type of industrial field is extremely large.
【図１】転炉吹錬末期の炉内圧力とスラグ中（Ｆｅ
Ｏ）、吹錬前後の脱硫率、およびマンガン鉱石還元率の
関係を示すグラフFig. 1 Furnace pressure and slag content (Fe
O), a graph showing the relationship between the desulfurization rate before and after blowing and the reduction rate of manganese ore.
【図２】底吹き攪拌力とスラグ中（ＦｅＯ）、吹錬前後
の脱硫率、およびマンガン鉱石還元率の関係を示すグラ
フFIG. 2 is a graph showing the relationship among bottom blowing agitation power, slag (FeO), desulfurization rate before and after blowing, and manganese ore reduction rate.
【図３】スラグのＣａＯ／ＳｉＯ２とスラグ中（Ｆｅ
Ｏ）、吹錬前後の脱硫率、およびマンガン鉱石還元率の
関係を示すグラフFIG. 3 shows CaO / SiO 2 of slag and the content of slag (Fe
O), a graph showing the relationship between the desulfurization rate before and after blowing and the reduction rate of manganese ore.
【図４】本発明を実施するための装置を説明する転炉の
断面図FIG. 4 is a sectional view of a converter illustrating an apparatus for carrying out the present invention.
フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) C21C 1/02 C21C 5/28 - 5/36 C21C 7/00,7/064 C21C 7/076,7/10 Continuation of the front page (58) Field surveyed (Int.Cl. 7 , DB name) C21C 1/02 C21C 5/28-5/36 C21C 7 / 00,7 / 064 C21C 7 / 076,7 / 10
Claims (1)
を複合吹錬転炉で脱炭しながらマンガン鉱石を投入して
還元するさい、吹錬末期にスラグ排滓を施すこと無く底
吹きガスの流量を０．１Ｎｍ3 ／ｍｉｎ・ｔ以上で攪拌
しつつ、転炉内を４００Ｔｏｒｒ以下に減圧して、スラ
グのＣａＯ／ＳｉＯ2 を２．５以上に調整することによ
り、溶鋼の脱硫促進とマンガン鉱石の還元を効率よく行
なうことを特徴とする転炉の精練方法。When reducing manganese ore while decarburizing the hot metal that has been dephosphorized in the hot metal pretreatment while decarburizing it in a combined blowing converter, the slag is discharged without slag discharge at the end of blowing. Desulfurization of molten steel by reducing the pressure in the converter to 400 Torr or less and adjusting the slag CaO / SiO 2 to 2.5 or more while stirring the flow rate of the blown gas at 0.1 Nm 3 / min · t or more. A scouring method for a converter characterized by efficiently promoting and reducing manganese ore.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01817192A JP3176679B2 (en) | 1992-01-06 | 1992-01-06 | Converter scouring method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01817192A JP3176679B2 (en) | 1992-01-06 | 1992-01-06 | Converter scouring method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0693322A JPH0693322A (en) | 1994-04-05 |
| JP3176679B2 true JP3176679B2 (en) | 2001-06-18 |
Family
ID=11964170
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01817192A Expired - Fee Related JP3176679B2 (en) | 1992-01-06 | 1992-01-06 | Converter scouring method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3176679B2 (en) |
-
1992
- 1992-01-06 JP JP01817192A patent/JP3176679B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0693322A (en) | 1994-04-05 |
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