JPH0341525B2 - - Google Patents
Info
- Publication number
- JPH0341525B2 JPH0341525B2 JP23604387A JP23604387A JPH0341525B2 JP H0341525 B2 JPH0341525 B2 JP H0341525B2 JP 23604387 A JP23604387 A JP 23604387A JP 23604387 A JP23604387 A JP 23604387A JP H0341525 B2 JPH0341525 B2 JP H0341525B2
- Authority
- JP
- Japan
- Prior art keywords
- molten steel
- temperature
- low
- converter
- ladle
- 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 - Lifetime
Links
- 229910000831 Steel Inorganic materials 0.000 claims description 46
- 239000010959 steel Substances 0.000 claims description 46
- 238000000034 method Methods 0.000 claims description 19
- 238000007670 refining Methods 0.000 claims description 10
- 238000007654 immersion Methods 0.000 claims description 6
- 238000007664 blowing Methods 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002253 acid Substances 0.000 claims description 3
- 229910000838 Al alloy Inorganic materials 0.000 claims 1
- 230000004907 flux Effects 0.000 claims 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 17
- 239000003795 chemical substances by application Substances 0.000 description 8
- 229910052742 iron Inorganic materials 0.000 description 8
- 238000006477 desulfuration reaction Methods 0.000 description 6
- 230000023556 desulfurization Effects 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 239000002893 slag Substances 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 238000009850 CAS-OB (composition adjustment by sealed argon bubbling with oxygen blowing) Methods 0.000 description 3
- 229910000805 Pig iron Inorganic materials 0.000 description 3
- 238000003723 Smelting Methods 0.000 description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 230000003009 desulfurizing effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 2
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 2
- 235000011941 Tilia x europaea Nutrition 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000004571 lime Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000010309 melting process Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000010079 rubber tapping Methods 0.000 description 2
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- 239000005997 Calcium carbide Substances 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- 235000012255 calcium oxide Nutrition 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 229910000514 dolomite Inorganic materials 0.000 description 1
- 239000010459 dolomite Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 235000017550 sodium carbonate Nutrition 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- CLZWAWBPWVRRGI-UHFFFAOYSA-N tert-butyl 2-[2-[2-[2-[bis[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]amino]-5-bromophenoxy]ethoxy]-4-methyl-n-[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]anilino]acetate Chemical compound CC1=CC=C(N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)C(OCCOC=2C(=CC=C(Br)C=2)N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)=C1 CLZWAWBPWVRRGI-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Description
（産業上の利用分野）
本発明は低級屑鉄の多量使用時における低Ｐ、
低Ｓ鋼の溶製方法に関する。
（従来の技術）
近年、鉄鋼業界においては、構造物の解体屑等
の老廃屑の増加に伴ない、この再利用のメリツト
を享受すべく鉄屑の多量使用技術の開発が急がれ
ている。
しかしながら該老廃屑は成分の不明な、低級屑
が主体であり、そのため転炉等の溶製炉で溶解し
た場合しばしば高Ｐ、高Ｓとなり所望の鋼成分に
合致せず、従つて低級な製品としたり、或いは再
溶解をすることにより、他の溶鋼と混合して有害
なＰ，Ｓなどを希釈して再溶製をする方法が一般
にとられている。
又、転炉に屑鉄と溶銑を装入して精錬するにあ
たり、鉄屑からのＰ，Ｓのピツクアツプを考慮し
て、例えば特開昭52−127420号公報に示すように
低Si含有溶銑にソーダ灰を添加して予め溶銑中の
Ｐ，Ｓを除去し、結果として転炉に装入される鉄
原料のＰおよびＳの量を低減させておく方法もあ
るが、前述の如く屑鉄の成分を精錬前に完全に把
握することは不可能であるので、結果として過剰
処理となり溶製コストが高くなる。
前述の転炉での再溶製法にしても、再溶製のた
めの費用が必要であり、又後工程の生産を停止す
る等のため生産能力に及ぼす影響は大であるとい
う問題がある。
（発明が解決しようとする問題点）
これ等の方法ではいかに高純化精錬を行なつて
もＰ，Ｓの除去には限界があり著しい経済的損失
も伴う。また、転炉より出鋼した取鍋内溶鋼の
Ｐ，Ｓ成分が目標より高めに外れた場合には、取
鍋内での安価な脱Ｐ、脱Ｓ方法は無く、転炉に返
戻した後、再吹錬する方法が一般に採用されるの
で莫大な損失を伴なう等の欠点を有していた。
本発明は前記した問題点を解決すべく極めて効
率的な溶鋼の脱Ｐ、脱Ｓ溶製法を提供しようとす
るものである。
（問題点を解決するための手段）
以下本発明による脱Ｐ、脱Ｓ溶鋼の精錬法につ
いて述べる。
本発明は溶鋼の精錬に際して転炉の潜在機能の
積極的な活用と取鍋の二次精錬炉の潜在機能の併
合活用により著しく優れた溶鋼精錬を実現したも
ので、転炉における低温吹錬と取鍋のAl添加吹
酸昇熱と該取鍋の脱硫精錬とを時系列的に、且つ
有機的に結合することにある。
本発明は転炉内溶鋼の吹錬終り（以下吹止めと
称する）温度を極めて低温とすることにより、転
炉での脱Ｐ反応を促進させ低Ｐ溶鋼を溶製するこ
とができるという知見に基づくものである。即ち
精錬炉内での脱Ｐ反応は式
log（％P2O5）／〔％Ｐ〕2×（％T.Fe）＝Ａ／Ｔ＋Ｂ
で表わされ
る。
ここで（％P2O5）はスラグ中のP2O5濃度、（％
T.Fe）はスラグ中のFeoOnの濃度であり〔％Ｐ〕
は溶鋼中のＰ濃度を表わしている。又、Ｔは溶鋼
の絶対温度である。
上式から明らかな様に精錬炉内の溶鋼の吹止温
度を低目にすることにより溶鋼中〔Ｐ〕濃度は低
くなり、その割合は低温になる程大である。
溶鋼中〔Ｐ〕濃度は夫々の溶製炉の脱Ｐ能、即
ち上式右辺の係数Ａ，Ｂの値により決定される
が、本発明に用いて転炉では吹止温度を1650℃か
ら1600℃に下げて出鋼時の温度降下を考慮し取鍋
温度を（LL）＋10〜40℃としたことにより溶鋼中
〔Ｐ〕濃度は石灰、ドロマイト等の造滓剤を同量
にしたにもかかわらず、0.022％から0.012％に下
つた。
このように低温でかつ低Ｐ、高Ｓで出鋼した取
鍋内溶鋼は次に脱Ｐするために昇温が必要であ
る。
本発明の如く取鍋内溶鋼を昇温した後脱Ｓを積
極的に実施する場合の取鍋内溶鋼昇熱装置の具備
条件を実操業上と治金反応から考察した結果、溶
鋼の短時間高速昇温が可能であることが製鋼作業
上最も重要であり、かつ溶鋼の昇温後に行なわれ
る脱Ｓ効率を向上させるAl2O3の生成が速やかに
起つていることが重要であることを知見し得た。
取鍋内溶鋼の昇熱方法としては、溶鋼内に浸漬
した浸漬管の中にAlを連続的に投入すると同時
に上方より酸素を吹付けてAlを酸化燃焼させ溶
鋼を昇温する方法（以下CAS−OBと称する）が
前記の条件を十分達成し得ることも判明した。こ
のCAS−OB法はAlを酸素によつて酸化発熱させ
て溶鋼を昇熱するためAlと酸素の量を増加する
ことにより簡単に高い昇温速度が得られ、通常15
〜20℃／minの昇温を行つている。
一方、溶鋼の昇温後の脱ＳについてもＳの活性
を高めるAl2O3の生成が重要である。即ちCAS−
OB法は大気圧下でAlを酸化させるため、Alが優
先的に酸化し効率的にAl2O3を生成する。
このような状態において該溶鋼内に例えば生石
灰、カルシウムカーバイド、ソーダ灰かあるいは
これ等にCaF2等の助剤を配合した脱硫剤を添加
するとともに、鍋底部から不活性ガスを導入し該
溶鋼と脱硫剤を撹拌処理する。この反応は高
Al2O3含有スラグが存在する浸漬管直下において
可及的速やかに進行し、極めて高い脱硫率が達成
される。また、この場合、脱Ｓ剤を溶鋼中に浸漬
ランスで吹込む方法が浸漬管内に脱Ｓ剤を投入す
るよりも脱Ｓ効率が高く、より好ましい。
この様に低級屑を転炉で使用する場合、溶製後
の溶鋼成分のＰ，Ｓが高めに外れることが度々で
あるが、転炉での低温吹止めによる脱Ｐ量の増
加、その後の取鍋溶鋼のCAS−OBによる短時間
高速昇温、次いで浸漬管内あるいはランスによる
脱Ｓ剤の吹込による脱Ｓにより極めて効率的な鋼
の溶製が可能である。
また、前述の取鍋内溶鋼温度が液相温度（LL）
に対し10℃より低いとAl添加による吹酸昇熱
以前に凝結し大幅な歩留低下及び流動性不良に伴
う反応低下を生ずる。一方40℃よりも高くなる
と転炉の低温精錬が不十分となる低Ｐ鋼が得られ
ないとともに、転炉の冷材である低級スタラツ
プ、型銑等の使用が制限される。さらにまた、取
鍋内溶鋼温度を（LL）＋10〜40℃とした際の吹止
温度は出鋼時の温度降下を上積した温度となり、
通常30〜60℃加算した超低温吹止温度となり、こ
の温度は通常吹止温度よりも少なくとも40〜50℃
低目となる。
なお、低級屑に限ることなくＰ，Ｓの高い低級
銑を用いる場合も同等の効果が得られる。
（実施例）
以下に本発明による低Ｐ、低Ｓ鋼溶製の一実施
例について述べる。
第１図は本発明の溶製プロセスのフロー概念図
である。
先づ転炉で吹錬するに先立ち、多量の屑鉄と溶
銑を転炉内に装入する。その後上方のランスより
酸素を吹込むことにより溶解精錬される。この際
転炉内には造滓剤を投入し、溶鋼の脱Ｓ、脱Ｐを
行なう。
この時転炉の吹止め温度を取鍋内溶鋼温度が溶
鋼の凝固温度上10〜40℃になるように操業するこ
とが脱Ｐ能を高めることに極めて重要である。即
ち前述の如く、脱Ｐ能は１／Ｔに比例するので溶
鋼温度が低い程反比例的に急激に溶鋼Ｐが低くな
ることを表わしている。
このようにして操業した本発明と従来法との比
較を表１に示す。
(Industrial Application Field) The present invention provides low P when using a large amount of low grade scrap iron,
This invention relates to a method for producing low S steel. (Conventional technology) In recent years, in the steel industry, as the amount of old waste such as demolition waste of structures has increased, there has been an urgent need to develop technology for using large amounts of iron scrap in order to enjoy the benefits of reusing this scrap. . However, this old waste is mainly low-grade waste whose composition is unknown, and therefore, when melted in a smelting furnace such as a converter, it often becomes high P and high S, which does not match the desired steel composition, resulting in a low-grade product. Generally, a method is used in which the harmful P, S, etc. are diluted by mixing with other molten steel, or by remelting. In addition, when charging scrap iron and hot metal into a converter for refining, taking into consideration the pick-up of P and S from iron scrap, for example, as shown in JP-A-52-127420, soda is added to low-Si content hot metal. There is a method of adding ash to remove P and S in the hot metal in advance, thereby reducing the amount of P and S in the iron raw material charged to the converter, but as mentioned above, it is possible to reduce the amount of P and S in the iron raw material charged to the converter. Since it is impossible to fully understand the process before refining, this results in overtreatment and high melting costs. Even with the above-mentioned remelting method using a converter, there are problems in that the cost for remelting is required and the production capacity is significantly affected due to the need to stop production in subsequent steps. (Problems to be Solved by the Invention) In these methods, no matter how highly purified the material is, there is a limit to the removal of P and S, and significant economic losses are also involved. In addition, if the P and S components of the molten steel in the ladle tapped from the converter are higher than the target, there is no inexpensive method for removing P and S in the ladle, and after returning the steel to the converter, However, since the method of reblowing is generally adopted, it has disadvantages such as huge losses. The present invention aims to solve the above-mentioned problems by providing an extremely efficient process for removing P and S from molten steel. (Means for Solving the Problems) A method for refining P-free and S-free molten steel according to the present invention will be described below. The present invention achieves extremely superior molten steel refining by actively utilizing the latent functions of the converter and by combining the latent functions of the secondary refining furnace of the ladle. The objective is to organically combine the Al-added blown acid heating in the ladle and the desulfurization refining in the ladle in a chronological manner. The present invention is based on the knowledge that by setting the blowing end (hereinafter referred to as the blow stop) temperature of molten steel in the converter to an extremely low temperature, the deP reaction in the converter can be promoted and low-P molten steel can be produced. It is based on In other words, the dephosphorization reaction in the smelting furnace is expressed by the formula log(%P 2 O 5 )/[%P] 2 × (%T.Fe)=A/T+B
It is expressed as Here, (%P 2 O 5 ) is the concentration of P 2 O 5 in the slag, (%
T.Fe) is the concentration of Fe o On in the slag [%P]
represents the P concentration in molten steel. Further, T is the absolute temperature of molten steel. As is clear from the above equation, by lowering the blow-off temperature of the molten steel in the refining furnace, the concentration of [P] in the molten steel decreases, and its proportion increases as the temperature decreases. The [P] concentration in molten steel is determined by the P removal ability of each smelting furnace, that is, the values of coefficients A and B on the right side of the above equation. By lowering the ladle temperature to (LL) + 10 to 40°C in consideration of the temperature drop during tapping, the concentration of [P] in molten steel can be reduced even if the same amount of slag forming agents such as lime and dolomite are used. Regardless, it fell from 0.022% to 0.012%. The molten steel in the ladle tapped at such a low temperature, low P, and high S needs to be heated in order to remove P. As a result of considering the conditions for a heating device for heating molten steel in a ladle when actively removing S after heating the molten steel in a ladle as in the present invention from actual operation and metallurgical reactions, we found that The ability to rapidly raise the temperature is most important in steelmaking work, and it is important that the generation of Al 2 O 3 , which improves the S removal efficiency after heating the molten steel, occurs quickly. I was able to find out. A method of raising the temperature of molten steel in a ladle is to continuously introduce Al into a immersion tube immersed in the molten steel, and at the same time blow oxygen from above to oxidize and burn the Al, raising the temperature of the molten steel (hereinafter referred to as CAS). -OB) was also found to be able to satisfactorily achieve the above conditions. This CAS-OB method raises the temperature of molten steel by oxidizing Al with oxygen, so a high temperature increase rate can be easily obtained by increasing the amount of Al and oxygen, and usually 15
The temperature is raised at ~20℃/min. On the other hand, the generation of Al 2 O 3 that increases the activity of S is also important for removing S after the temperature of molten steel is increased. That is, CAS-
Since the OB method oxidizes Al under atmospheric pressure, Al oxidizes preferentially and efficiently generates Al 2 O 3 . In this state, a desulfurizing agent such as quicklime, calcium carbide, soda ash, or a mixture of these with an auxiliary agent such as CaF 2 is added to the molten steel, and an inert gas is introduced from the bottom of the pot to remove the molten steel. Stir the desulfurizing agent. This reaction is highly
Desulfurization proceeds as quickly as possible directly under the immersion pipe where Al 2 O 3 -containing slag exists, achieving an extremely high desulfurization rate. Further, in this case, a method in which the desulfurization agent is injected into the molten steel using an immersion lance is more preferable than a method in which the desulfurization agent is introduced into the immersion tube because the S removal efficiency is higher. When low-grade scrap is used in a converter like this, the P and S of the molten steel components after melting often become too high. Extremely efficient steel melting is possible by rapidly raising the temperature of molten steel in a ladle using CAS-OB, and then removing S by blowing a desulfurizing agent into a dipping tube or using a lance. In addition, the temperature of the molten steel in the ladle mentioned above is the liquidus temperature (LL).
On the other hand, if the temperature is lower than 10°C, the blown acid will condense before it is heated by the addition of Al, resulting in a significant decrease in yield and a decrease in reaction due to poor fluidity. On the other hand, if the temperature is higher than 40°C, low-P steel cannot be obtained due to insufficient low-temperature refining in the converter, and the use of low-grade stirrup, molded pig iron, etc., which are cold materials for the converter, is restricted. Furthermore, when the temperature of molten steel in the ladle is set to (LL) + 10 to 40℃, the blow-off temperature is the temperature obtained by adding the temperature drop during tapping,
The ultra-low blowout temperature is typically 30 to 60°C higher, and this temperature is at least 40 to 50°C higher than the normal blowout temperature.
It will be low. Note that the same effect can be obtained not only when using low-grade pig iron but also when using low-grade pig iron with high P and S contents. (Example) An example of producing low P and low S steel according to the present invention will be described below. FIG. 1 is a conceptual flow diagram of the melting process of the present invention. Before blowing in a converter, a large amount of scrap iron and hot metal are charged into the converter. It is then melted and refined by blowing oxygen through an upper lance. At this time, a slag-forming agent is introduced into the converter to remove S and P from the molten steel. At this time, it is extremely important to operate the converter so that the blow-off temperature and the temperature of the molten steel in the ladle are 10 to 40°C above the solidification temperature of the molten steel in order to improve the dephosphorization ability. That is, as described above, since the P removal ability is proportional to 1/T, this means that the lower the molten steel temperature, the more rapidly the molten steel P decreases inversely proportionally. Table 1 shows a comparison between the present invention and the conventional method operated in this manner.
【表】【table】
【表】
表１は脱Ｐのために使用する転炉投入用石灰の
使用量を等量としかつパウダーインジエクシヨン
（PI）あるいはCASで使用する脱Ｓ剤を等量にし
て従来法と比較したものである。
転炉吹止め時のＰは吹止温度が本発明法では
1600℃であるが従来法は1670℃と高温になり、そ
の結果本発明法ではＰ＝0.009％まで下げ得た。
又PIによる脱Ｓについても効率が極めて良く
Ｓ＝0.005％まで下つている。
このように本発明法によれば合計の処理時間を
極度に延長する（CAS−OBによる昇熱時間）こ
となく十分満足出来る低Ｐ、低Ｓ鋼を効率的に得
ることが出来た。
（発明の効果）
以上述べた如く、本発明は従来益々増加するで
あろう低級屑鉄を転炉で多量溶解する上での高
Ｓ、高Ｐ救済として効率的な脱Ｐ、脱Ｓ法を提供
するものであり産業上裨益なところが極めて大で
ある。[Table] Table 1 compares the conventional method with the same amount of lime used for dephosphorization and the same amount of desulfurization agent used in powder injection (PI) or CAS. This is what I did. P at the time of converter blow-off is determined by the blow-off temperature in the method of the present invention.
The conventional method resulted in a high temperature of 1670°C, whereas the method of the present invention was able to lower P to 0.009%. In addition, the efficiency of S removal by PI is extremely high and S = 0.005%. As described above, according to the method of the present invention, it was possible to efficiently obtain a sufficiently satisfactory low P and low S steel without extremely prolonging the total processing time (heating time due to CAS-OB). (Effects of the Invention) As described above, the present invention provides an efficient de-P and de-S method as a remedy for high S and high P when melting a large amount of low-grade scrap iron in a converter, which is expected to increase more and more. The industrial benefits are extremely large.
第１図は本発明の溶製プロセスフローである。 FIG. 1 is a melting process flow of the present invention.
Claims (1)
した取鍋内溶鋼温度を該溶鋼の液相温度（LL）
より10〜40℃高目にするとともに、該取鍋内溶鋼
に浸漬管を挿入し、該浸漬管を介して金属Alあ
るいはAl合金を添加しつつランスにより吹酸昇
熱した後、該溶鋼にフラツクスを添加して脱
〔Ｓ〕することを特徴とする低Ｐ，Ｓ溶鋼の精錬
法。[Claims] 1. Converter refining is performed at an ultra-low temperature stop, and the temperature of the molten steel in the ladle discharged from the converter is defined as the liquidus temperature (LL) of the molten steel.
At the same time, an immersion pipe is inserted into the molten steel in the ladle, and metal Al or Al alloy is added through the immersion pipe, and the temperature is increased by blowing acid with a lance. A refining method for low P, S molten steel characterized by adding flux to remove [S].
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23604387A JPS6479316A (en) | 1987-09-19 | 1987-09-19 | Method for refining low p, s molten steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23604387A JPS6479316A (en) | 1987-09-19 | 1987-09-19 | Method for refining low p, s molten steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6479316A JPS6479316A (en) | 1989-03-24 |
| JPH0341525B2 true JPH0341525B2 (en) | 1991-06-24 |
Family
ID=16994913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23604387A Granted JPS6479316A (en) | 1987-09-19 | 1987-09-19 | Method for refining low p, s molten steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6479316A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100973651B1 (en) * | 2003-07-16 | 2010-08-02 | 주식회사 포스코 | Process for excluding phosphate of ingot steel |
| CN112126737B (en) * | 2019-06-24 | 2022-04-15 | 上海梅山钢铁股份有限公司 | Production method of low-sulfur alloy molten steel |
-
1987
- 1987-09-19 JP JP23604387A patent/JPS6479316A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6479316A (en) | 1989-03-24 |
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