JPH0987720A - Method for decarburize-refining chromium-containing molten steel - Google Patents

Method for decarburize-refining chromium-containing molten steel

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Publication number
JPH0987720A
JPH0987720A JP25301695A JP25301695A JPH0987720A JP H0987720 A JPH0987720 A JP H0987720A JP 25301695 A JP25301695 A JP 25301695A JP 25301695 A JP25301695 A JP 25301695A JP H0987720 A JPH0987720 A JP H0987720A
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JP
Japan
Prior art keywords
slag
refining
amount
molten
cao
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.)
Granted
Application number
JP25301695A
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Japanese (ja)
Other versions
JP3160508B2 (en
Inventor
Naoki Kikuchi
直樹 菊池
Yasuo Kishimoto
康夫 岸本
Hideji Takeuchi
秀次 竹内
Nagayasu Bessho
永康 別所
Yukio Takahashi
幸雄 高橋
Masanori Nishigori
正規 錦織
Hiroshi Nishikawa
廣 西川
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JFE Steel Corp
Original Assignee
Kawasaki Steel Corp
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Treatment Of Steel In Its Molten State (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)

Abstract

PROBLEM TO BE SOLVED: To improve the overall yield of valuable metals such as Cr, etc., by limiting Cr2 O3 -containing slag produced at the time of decarburize-refining Cr-containing molten steel to a specified quantity and also, utilizing the slag for the next decarburize-refining of the Cr-containing molten steel. SOLUTION: High carbon and low chromium molten iron is charged into a top/ bottom blowing converter type refining furnace, and Fe-Cr is added as a Cr supplement source and gas is blown from bottom-blown tuyere to stir the molten iron. Gaseous oxygen is injected from a top-blown lance and C in the Cr-containing molten iron is oxidized and decarburized to melt a stainless steel having 16-18% Cr. In this case, a part of Cr is oxidized together with the decarburizing reaction by the oxygen blowing and shifted into molten slag as Cr2 O3 . During this refining, CaO, etc., as a slag-making agent is added and the molten slag having 0.8-2.5 basicity is limited to <=50kg/ton of the molten steel. The molten stainless steel is tapped from the converter and the Cr2 O3 -containing slag is left in the furnace for use in the next decarburize-refining of the Cr-containing molten iron, and the molten slag is reduced into Cr by C in the high carbon and Cr-containing molten iron and recovered as Cr in a high yield.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】この発明は、含クロム溶鋼の
脱炭精錬方法に関し、とくにスラグ中の有価金属を還元
回収しない未還元法または軽還元法において、精錬中に
おけるCr酸化量を低減すると共に、リサイクルスラグを
有効に活用することにより、精錬能率の一層の向上を図
ろうとするものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for decarburizing and refining molten steel containing chromium, and particularly for reducing the amount of Cr oxidation during refining in an unreduced method or a light reduction method in which valuable metals in slag are not reduced and recovered. , It aims to further improve the refining efficiency by effectively utilizing recycled slag.

【０００２】[0002]

【従来の技術】一般に、含クロム溶鋼の脱炭精錬では、
吹錬中に酸化生成したクロム酸化物を、吹精終了後、Al
やFeSiなどの還元剤によって鋼中に還元回収している。
また、この発明法のように、還元剤を使用せず、クロム
酸化物を含有するスラグを次回の脱炭精錬またはクロム
鉱石の溶融還元精錬にリサイクル使用する方法もある。
かようなリサイクル方法としては、特開平７-62413号公
報、特開昭62−243711号公報および特開平２−232312号
公報に記載の方法がある。2. Description of the Related Art Generally, in decarburizing and refining molten steel containing chromium,
Chromium oxide that was oxidized during the blowing process was removed from the aluminum
It is reduced and recovered in steel by a reducing agent such as FeSi and FeSi.
There is also a method like this invention method in which a reducing agent is not used and slag containing chromium oxide is recycled for the next decarburization refining or smelting reduction refining of chromium ore.
As such a recycling method, there are methods described in JP-A-7-62413, JP-A-62-243711 and JP-A-2-232312.

【０００３】この中で特開平７-62413号公報および特開
昭62−243711号公報に記載の方法は、脱炭精錬終了後、
未還元スラグを炉内に残留させ、次回の脱炭精錬工程の
高炭素濃度操業中に、次式 (Cr2O3) ＋ 3〔Ｃ〕＝ 2〔Cr〕＋ 3 CO の反応により還元回収するものである。Among them, the methods described in JP-A-7-62413 and JP-A-62-243711 are:
Unreduced slag remains in the furnace and is reduced and recovered by the reaction of the following formula (Cr 2 O 3 ) +3 [C] = 2 [Cr] + 3CO during the next high carbon concentration operation in the decarburization refining process. To do.

【０００４】[0004]

【発明が解決しようとする課題】しかしながら、上記の
方法では、スラグの増加に伴ってクロム酸化量の増加を
招き、その結果クロムの酸化ロスが増大するいうところ
に問題を残していた。また、脱炭精錬後の含クロムスラ
グを還元せずに、次のチャージまたは溶融還元炉にリサ
イクルする場合は、上掲式の反応が生じにくいというと
ころに問題を残していた。However, the above method has a problem in that the amount of chromium oxidation increases with an increase in slag, resulting in an increase in chromium oxidation loss. Further, when the chromium-containing slag after decarburizing and refining is not recycled but is recycled to the next charge or smelting reduction furnace, there remains a problem in that the above-mentioned reaction is difficult to occur.

【０００５】この発明は、上記の問題を有利に解決すべ
く開発されたもので、脱炭精錬によって生成したスラグ
中のクロムを還元回収しない未還元法または軽還元法に
おいて、スラグ量増加に伴うクロム酸化量の増大を阻止
するために、 スラグ量を低減する、 同一スラグ量においても、より低塩基度として次式 (Cr2O3) ＋ 3〔Ｃ〕＝ 2〔Cr〕＋ 3 CO に示すスラグ−メタル間反応を促進する、ことにより、
脱炭精錬中におけるクロム酸化量を効果的に低減すると
共に、リサイクルスラグの還元反応を促進することによ
り、未還元法における溶鋼中Cr歩留りの有利な向上を図
ったものである。The present invention was developed in order to advantageously solve the above problems, and is accompanied by an increase in the amount of slag in the unreduced method or the light reduction method in which the chromium in the slag produced by decarburization refining is not reduced and recovered. To prevent an increase in the amount of chromium oxidation, reduce the amount of slag. Even with the same amount of slag, a lower basicity of the following formula (Cr 2 O 3 ) + 3 [C] = 2 [Cr] + 3 CO By promoting the slag-metal reaction shown,
By effectively reducing the amount of chromium oxidation during decarburization refining and accelerating the reduction reaction of recycled slag, the yield of Cr in molten steel in the unreduced method is advantageously improved.

【０００６】[0006]

【課題を解決するための手段】すなわち、この発明は、
精錬ガスの上吹き機能または上底吹き両機能をそなえる
容器内で含クロム溶鋼を脱炭精錬したのち、スラグ中の
有価金属を還元回収することなしにまたは軽還元したの
ち出鋼する含クロム溶鋼の脱炭精錬方法において、吹錬
中における（CaO + SiO2）量が 50 kg/t以下となるよう
に添加フラックス量を調整することを特徴とする含クロ
ム溶鋼の脱炭精錬方法（第１発明）である。That is, the present invention provides:
Chromium-containing molten steel that is discharged after decarburizing and refining molten chromium-containing steel in a container that has both top-blowing and top-bottoming functions of refining gas, and then without recovering and recovering valuable metals in slag or after light reduction. In the decarburizing and refining method of No. 1, the amount of added flux is adjusted so that the amount of (CaO + SiO 2 ) during blowing is 50 kg / t or less. Invention).

【０００７】また、この発明は、精錬ガスの上吹き機能
または上底吹き両機能をそなえる容器内で含クロム溶鋼
を脱炭精錬したのち、スラグ中の有価金属を還元回収す
ることなしにまたは軽還元したのち出鋼し、該チャージ
で生成したスラグは、該容器内に一部または全量残留さ
せて、次回の脱炭精錬に利用する含クロム溶鋼の脱炭精
錬方法において、次回の吹錬中における（CaO + SiO2）
量が 50 kg/t以下となるように添加フラックス量および
／または残留スラグ量を調整することを特徴とする含ク
ロム溶鋼の脱炭精錬方法（第２発明）である。Further, according to the present invention, after chromium-containing molten steel is decarburized and refined in a container having both a top blowing function and a bottom blowing function of refining gas, the valuable metal in the slag is not recovered or recovered lightly. In the decarburizing and refining method of molten chromium-containing steel to be used for the next decarburizing and refining, the slag produced by the reduction and then tapping, and the slag generated by the charge is partially or wholly retained in the container during the next blowing. At (CaO + SiO 2 )
A method for decarburizing and refining molten steel containing chromium (2nd invention), characterized in that the amount of added flux and / or the amount of residual slag is adjusted so that the amount becomes 50 kg / t or less.

【０００８】さらに、この発明は、上記の第１または第
２発明において、さらにスラグ塩基度（CaO/SiO2）を
0.8〜2.5 の範囲に調整した含クロム溶鋼の脱炭精錬方
法（第３発明）である。Furthermore, the present invention is characterized in that, in the above first or second invention, the slag basicity (CaO / SiO 2 ) is further increased.
It is a method for decarburizing and refining molten chromium-containing steel (third invention) adjusted to a range of 0.8 to 2.5.

【０００９】[0009]

【発明の実施の形態】含クロム溶鋼の脱炭精錬では、鋼
中のCrによりＣの活量が低下し、脱Ｃと同時にCr酸化が
生じる Cr酸化速度＝酸化Cr生成速度(1) −酸化Cr還元速度(2) ---(3) 2〔Cr〕＋ 3/2 O2 ＝ (Cr2O3) ---(1) (Cr2O3) ＋ 3〔Ｃ〕＝ 2〔Cr〕＋ 2 CO ---(2) 脱炭中のCr酸化は (3)式に示されるように、供給された
酸素ガスによってCrが酸化される (1)式の反応と、酸化
したクロム酸化物が鋼中〔Ｃ〕によって還元される(2)
式の反応のバランスで決まる。そのうち (2)式の反応速
度は ｄ〔Cr〕／dt＝−Ａ／Ｖ・ｋ・〔 (％Cr) − (％Cr)e) 〕 と表せる。 ここで、Ａ：スラグ−メタル反応界面積 Ｖ：浴体積 ｋ：還元反応速度定数 （ ）〔 〕はそれぞれスラグ中、メタル中を表す。BEST MODE FOR CARRYING OUT THE INVENTION In the decarburization refining of molten steel containing chromium, the activity of C is reduced by Cr in the steel, and Cr oxidation occurs at the same time as decarbonization Cr oxidation rate = Cr oxide formation rate (1) -oxidation Cr reduction rate (2) --- (3) 2 [Cr] + 3/2 O 2 = (Cr 2 O 3 ) --- (1) (Cr 2 O 3 ) + 3 [C] = 2 [Cr ] + 2 CO --- (2) Cr oxidation during decarburization is, as shown in Eq. (3), the reaction of Eq. (1) in which Cr is oxidized by the supplied oxygen gas, and the oxidation of oxidized chromium. Things are reduced by [C] in steel (2)
It is determined by the balance of the reaction of the formula. Among them, the reaction rate of equation (2) can be expressed as d [Cr] / dt = -A / Vk [[(% Cr)-(% Cr) e)]. Here, A: slag-metal reaction interface area V: bath volume k: reduction reaction rate constant () [] respectively represent the inside of the slag and the inside of the metal.

【００１０】スラグ量が増加した場合、 (1)式により生
成した (Cr2O3)つまりスラグ中のCr濃度が、スラグ量が
多いために希釈される結果、 (2)式の反応速度が小さく
なる。そのため (3)式より、 (1)式で示される酸化クロ
ム生成速度が一定の場合には、Cr酸化量が増大する。脱
炭精錬におけるスラグは、主に CaO, SiO2からなる。Si
O2量は、吹錬中の溶銑中のSiまたはFeCr合金中のSiより
生成するSiO2、コ−クス名の灰分に含まれるSiO2で決ま
る。また CaOは、それに対して供給する焼石灰量で決ま
る。When the amount of slag increases, the Cr concentration in the (Cr 2 O 3 ) generated by the formula (1), that is, the slag, is diluted due to the large amount of slag, resulting in the reaction rate of the formula (2). Get smaller. Therefore, from equation (3), when the chromium oxide production rate shown in equation (1) is constant, the amount of Cr oxidation increases. Slag in decarburization refining is mainly composed of CaO and SiO 2 . Si
The amount of O 2 is determined by SiO 2 produced from Si in the hot metal during blowing or Si in the FeCr alloy, and SiO 2 contained in the ash of the coke name. CaO is determined by the amount of calcined lime supplied to it.

【００１１】さて、発明者らは、クロム酸化量の増大を
招くことのない脱炭精錬を実現すべく、精錬時における
スラグ量に着目して実験を重ねた。その結果、図１に示
すように、スラグ量が（CaO ＋SiO2）換算で 50 kg/t以
下であれば、Cr酸化量を低位に安定して維持できること
の知見を得た。従って、第１発明では、吹錬中における
（CaO + SiO2）量が 50 kg/t以下となるように添加フラ
ックス量を調整することにしたのである。また、第２発
明では、次回の吹錬中における（CaO + SiO2）量が 50
kg/t以下となるように添加フラックス量および／または
残留スラグ量を調整することにしたのである。しかしな
がら、スラグ量があまりに少ないと、スロッピングやダ
ストの発生増加が顕著となるため、少なくとも 20 kg/t
程度は存在させることが好ましい。Now, the inventors have conducted experiments to pay attention to the amount of slag during refining in order to realize decarburization refining without increasing the amount of chromium oxidation. As a result, as shown in FIG. 1, it was found that the Cr oxidation amount can be stably maintained at a low level when the slag amount is 50 kg / t or less in terms of (CaO + SiO 2 ). Therefore, in the first invention, the amount of added flux was adjusted so that the amount of (CaO + SiO 2 ) during blowing was 50 kg / t or less. Further, in the second invention, the amount of (CaO + SiO 2 ) during the next blowing is 50
We decided to adjust the amount of added flux and / or the amount of residual slag so that it would be less than kg / t. However, if the amount of slag is too small, the amount of sloping and dust generation will increase significantly, so at least 20 kg / t.
It is preferred that the extent is present.

【００１２】また、発明者らは、図２に示すように、生
成したSiO2量に対する CaO量すなわち CaO／SiO2比が小
さい低塩基度で脱炭精錬を行う方が、スラグが軟化し、
前述した (2)式の反応が促進されるため、Cr酸化量の一
層の低減が可能になること、すなわち同一スラグ量でも
塩基度を低くした方が一層の効果が得られることも併せ
て見出した。同図より明らかなように、塩基度(CaO／Si
O2) が 2.5以下であれば、同一スラグ量においてCr酸化
量を効果的に低減することができた。このように、 CaO
／SiO2を 2.5以下とよることによってCr酸化量の効果的
な低減が達成できる理由は、スラグの液相が増加したた
めと考えられる。図３に、 Cr2O3存在下における CaO／
SiO2比とスラグの液相比率との関係を示したが、 CaO／
SiO2比が 2.5以下になるとスラグの液相比率が急激に上
昇している。しかしながら、 CaO／SiO2比が 0.8を下回
ると、図４に示すように、耐火物の損耗が著しくなるの
で、 CaO／SiO2比は 0.8〜2.5 の範囲に限定した。Further, as shown in FIG. 2, the inventors soften the slag by performing decarburization refining at a low basicity in which the amount of CaO with respect to the amount of SiO 2 produced, that is, the CaO / SiO 2 ratio is small.
It was also found that the reaction of formula (2) described above is promoted, so that it is possible to further reduce the amount of Cr oxidation, that is, lowering the basicity produces a greater effect even with the same amount of slag. It was As is clear from the figure, the basicity (CaO / Si
When O 2 ) is 2.5 or less, the amount of Cr oxidation could be effectively reduced with the same amount of slag. Thus, CaO
The reason why the amount of Cr oxidation can be effectively reduced by setting / SiO 2 to 2.5 or less is considered to be that the liquid phase of the slag increases. Figure 3 shows CaO / in the presence of Cr 2 O 3.
The relationship between the SiO 2 ratio and the liquid phase ratio of slag was shown.
When the SiO 2 ratio is 2.5 or less, the liquid phase ratio of slag rises sharply. However, CaO / SiO 2 ratio is below 0.8, as shown in FIG. 4, since the wear of the refractory becomes significant, CaO / SiO 2 ratio is limited to the range of 0.8 to 2.5.

【００１３】[0013]

【実施例】脱炭精錬条件は表１に示すとおりである。EXAMPLE The decarburizing and refining conditions are as shown in Table 1.

【表１】 [Table 1]

【００１４】かかる脱炭精錬において、残留スラグ量を
種々に変化させ、吹錬中の（ CaO＋SiO2）量とCr酸化量
との関係について調査した結果を図１に示す。同図より
明らかなように、吹錬中の（CaO + SiO2）量が 50 kg/t
以下であればCr酸化量を低く抑えることができた。また
図２には、(CaO＋SiO2）量とCr酸化量との関係に及ぼす
塩基度(CaO/SiO2)の影響について調べた結果を示した
が、同図から明らかなように、塩基度が 2.5以下になる
とスラグの液相比率が増加して、同一スラグ量でもCr酸
化量を低減することができた。In such decarburization refining, FIG. 1 shows the results of investigating the relationship between the amount of (CaO + SiO 2 ) and Cr oxidation during blowing while varying the amount of residual slag. As is clear from the figure, the amount of (CaO + SiO 2 ) during blowing is 50 kg / t.
If the amount is below, the amount of Cr oxidation could be suppressed low. In addition, Fig. 2 shows the results of examining the effect of basicity (CaO / SiO 2 ) on the relationship between the amount of (CaO + SiO 2 ) and the amount of Cr oxidation. When it was 2.5 or less, the liquid phase ratio of slag increased, and the amount of Cr oxidation could be reduced even with the same amount of slag.

【００１５】[0015]

【発明の効果】かくして、この発明に従い、脱炭精錬後
のスラグを還元回収しない未還元法または軽還元法にお
いて、吹錬中のスラグ（CaO + SiO2) 量を 50 kg/t以下
に制限し、さらにはスラグ塩基度を0.8 ≦ CaO／SiO2≦
2.5 の範囲に制御することにより、耐火物損耗増加を招
くことなしに、脱炭中におけるCr酸化量を安定して低位
に維持することができる。その結果、従来に比べてクロ
ムの酸化ロスを大幅に低減できるのでCr歩留りが向上
し、またCr酸化量推定により操業の安定も可能となっ
た。As described above, according to the present invention, the amount of slag (CaO + SiO 2 ) during blowing is limited to 50 kg / t or less in the unreduced method or the light reduction method in which the slag after decarburization refining is not reduced and recovered. In addition, the slag basicity is 0.8 ≤ CaO / SiO 2 ≤
By controlling in the range of 2.5, the amount of Cr oxidation during decarburization can be stably maintained at a low level without increasing the wear of refractory materials. As a result, the oxidation loss of chromium can be significantly reduced compared to the conventional method, so the Cr yield is improved and the stable operation can be achieved by estimating the amount of Cr oxidation.

【図面の簡単な説明】[Brief description of drawings]

【図１】吹錬中におけるスラグ（CaO ＋SiO2）量とCr酸
化量との関係を示したグラフである。FIG. 1 is a graph showing the relationship between the amount of slag (CaO + SiO 2 ) and the amount of Cr oxidation during blowing.

【図２】(CaO＋SiO2）量とCr酸化量との関係に及ぼす塩
基度(CaO/SiO2)の影響を示したグラフである。FIG. 2 is a graph showing the effect of basicity (CaO / SiO 2 ) on the relationship between the (CaO + SiO 2 ) amount and the Cr oxidation amount.

【図３】Cr2O3存在下における塩基度(CaO／SiO2) とス
ラグの液相比率との関係を示したグラフである。FIG. 3 is a graph showing the relationship between the basicity (CaO / SiO 2 ) and the liquid phase ratio of slag in the presence of Cr 2 O 3 .

【図４】スラグ塩基度とバレル耐火物損耗速度との関係
を示したグラフである。FIG. 4 is a graph showing the relationship between slag basicity and barrel refractory wear rate.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 竹内 秀次 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社技術研究所内 (72)発明者 別所 永康 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社技術研究所内 (72)発明者 高橋 幸雄 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社技術研究所内 (72)発明者 錦織 正規 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社千葉製鉄所内 (72)発明者 西川 廣 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社千葉製鉄所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuji Takeuchi 1 Kawasaki-cho, Chuo-ku, Chiba, Chiba Prefecture Inside the Technical Research Institute of Kawasaki Steel Co., Ltd. (72) Inventor Yukio Takahashi 1st Kawasaki-cho, Chuo-ku, Chiba, Chiba Prefecture In-house Technical Research Institute (72) Inventor Nishikiori, 1st Kawasaki-cho, Chuo-ku, Chiba-shi Kawasaki Steel Works Co., Ltd. Chiba Steel Works (72) Inventor Hiro Nishikawa 1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Kawasaki Steel Works Chiba Works

Claims (3)

【特許請求の範囲】[Claims] 【請求項１】 精錬ガスの上吹き機能または上底吹き両
機能をそなえる容器内で含クロム溶鋼を脱炭精錬したの
ち、スラグ中の有価金属を還元回収することなしにまた
は軽還元したのち出鋼する含クロム溶鋼の脱炭精錬方法
において、 吹錬中における（CaO + SiO2）量が 50 kg/t以下となる
ように添加フラックス量を調整することを特徴とする含
クロム溶鋼の脱炭精錬方法。1. A method of decarburizing and refining molten chromium-containing steel in a container having both a top blowing function and a bottom blowing function of refining gas, and then performing recovery without reducing or recovering valuable metal in slag or light recovery. In the decarburizing refining method for molten chromium-containing steel, the amount of added flux is adjusted so that the (CaO + SiO 2 ) content during blowing is 50 kg / t or less. Refining method. 【請求項２】 精錬ガスの上吹き機能または上底吹き両
機能をそなえる容器内で含クロム溶鋼を脱炭精錬したの
ち、スラグ中の有価金属を還元回収することなしにまた
は軽還元したのち出鋼し、該チャージで生成したスラグ
は、該容器内に一部または全量残留させて、次回の脱炭
精錬に利用する含クロム溶鋼の脱炭精錬方法において、 次回の吹錬中における（CaO + SiO2）量が 50 kg/t以下
となるように添加フラックス量および／または残留スラ
グ量を調整することを特徴とする含クロム溶鋼の脱炭精
錬方法。2. A method for decarburizing and refining molten chromium-containing steel in a vessel having both a top blowing function and a bottom blowing function of refining gas, and then performing recovery without recovery of the valuable metal in the slag or light reduction. In the decarburization refining method of molten chromium-containing steel to be used for the next decarburization refining, the slag produced by the steel is partially or wholly left in the container, and (CaO + A method for decarburizing and refining molten chromium-containing steel, which comprises adjusting the amount of added flux and / or the amount of residual slag so that the amount of SiO 2 ) is 50 kg / t or less. 【請求項３】 請求項１または２において、スラグ塩基
度（CaO/SiO2）を、0.8〜2.5 の範囲に調整した含クロ
ム溶鋼の脱炭精錬方法。3. The method for decarburizing and refining molten chromium-containing steel according to claim 1, wherein the slag basicity (CaO / SiO 2 ) is adjusted in the range of 0.8 to 2.5.
JP25301695A 1995-09-29 1995-09-29 Decarburization refining method of chromium-containing molten steel Expired - Fee Related JP3160508B2 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11264011A (en) * 1998-03-17 1999-09-28 Kawasaki Steel Corp Method for effective use of slag
WO2003083144A1 (en) * 2002-03-28 2003-10-09 Sms Demag Aktiengesellschaft Method for treating alloyed carbonic iron smelts used for the production of steel
JP2007063581A (en) * 2005-08-29 2007-03-15 Nippon Steel Corp Method for refining molten chromium-containing steel
CN116579670A (en) * 2023-07-13 2023-08-11 北京工业大学 Economic benefit calculation and feasibility assessment method for recycling thermal refining slag

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11264011A (en) * 1998-03-17 1999-09-28 Kawasaki Steel Corp Method for effective use of slag
WO2003083144A1 (en) * 2002-03-28 2003-10-09 Sms Demag Aktiengesellschaft Method for treating alloyed carbonic iron smelts used for the production of steel
JP2007063581A (en) * 2005-08-29 2007-03-15 Nippon Steel Corp Method for refining molten chromium-containing steel
CN116579670A (en) * 2023-07-13 2023-08-11 北京工业大学 Economic benefit calculation and feasibility assessment method for recycling thermal refining slag
CN116579670B (en) * 2023-07-13 2023-10-03 北京工业大学 Economic benefit calculation and feasibility assessment method for recycling thermal refining slag

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