JPH01188615A - Solid iron source melting method for obtaining high mn yield - Google Patents
Solid iron source melting method for obtaining high mn yieldInfo
- Publication number
- JPH01188615A JPH01188615A JP63012583A JP1258388A JPH01188615A JP H01188615 A JPH01188615 A JP H01188615A JP 63012583 A JP63012583 A JP 63012583A JP 1258388 A JP1258388 A JP 1258388A JP H01188615 A JPH01188615 A JP H01188615A
- Authority
- JP
- Japan
- Prior art keywords
- slag
- refining
- molten iron
- blowing
- iron
- 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
Links
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 110
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 51
- 239000007787 solid Substances 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000002844 melting Methods 0.000 title claims abstract description 15
- 230000008018 melting Effects 0.000 title claims abstract description 15
- 238000007670 refining Methods 0.000 claims abstract description 31
- 239000002893 slag Substances 0.000 claims abstract description 31
- 238000007664 blowing Methods 0.000 claims abstract description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 18
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 18
- 239000001301 oxygen Substances 0.000 claims abstract description 18
- 239000003575 carbonaceous material Substances 0.000 claims abstract description 15
- 238000006243 chemical reaction Methods 0.000 claims abstract description 6
- 238000002485 combustion reaction Methods 0.000 claims abstract description 4
- 239000002253 acid Substances 0.000 claims description 7
- 230000000717 retained effect Effects 0.000 abstract 1
- 229910052799 carbon Inorganic materials 0.000 description 19
- 239000002184 metal Substances 0.000 description 12
- 229910052751 metal Inorganic materials 0.000 description 12
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 6
- 229910000831 Steel Inorganic materials 0.000 description 6
- 239000000292 calcium oxide Substances 0.000 description 6
- 239000010959 steel Substances 0.000 description 6
- 235000012255 calcium oxide Nutrition 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 239000007789 gas Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 239000000843 powder Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- 239000003245 coal Substances 0.000 description 2
- 238000005261 decarburization Methods 0.000 description 2
- 229910000514 dolomite Inorganic materials 0.000 description 2
- 239000010459 dolomite Substances 0.000 description 2
- 238000011234 economic evaluation Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 229910002551 Fe-Mn Inorganic materials 0.000 description 1
- 229910015136 FeMn Inorganic materials 0.000 description 1
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 241000283080 Proboscidea <mammal> Species 0.000 description 1
- 235000009470 Theobroma cacao Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 244000240602 cacao Species 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000000112 cooling gas Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000010908 plant waste Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 239000000126 substance Substances 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
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、炭素物質を熱源としてスクラップなどの固体
鉄源を、溶解する方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for melting a solid iron source such as scrap using a carbon material as a heat source.
（従来の技術）
高炉−転炉プロセスのように、溶銑を主原料とした精錬
において、Ｍｎを含む溶鋼を製造する時は、通常高価な
Ｆｅ −Ｍｎの使用量を低減するため、転炉内にＭｎ源
として、Ｍｎ鉱石を添加し、炉内で溶鉄中の炭素による
還元か、あるいは還元用炭素源を添加し還元精錬を行な
って、溶製鋼種の規格範囲内で、できる限り鋼中Ｍｎを
高くすることを指向してきた。(Prior art) When producing molten steel containing Mn in refining using hot metal as the main raw material, such as in the blast furnace-converter process, in order to reduce the amount of expensive Fe-Mn used, Mn ore is added as a Mn source to the molten steel, and reduction is performed in a furnace using carbon in the molten iron, or reduction refining is performed by adding a reducing carbon source to reduce Mn in the steel as much as possible within the standard range of the molten steel type. The aim has been to increase the
（１） この時の転炉吹き止め条件は、通常１６００
℃〜１７００°ｃ、、Ｉ中Ｃ量を０．０５〜０．５０％
、スラグＴ、Ｆｅｌ Ｏ〜２５％、塩基度３．５〜５．
０であり、Ｍｎ鉱石の転炉内への添加時期やスラグ量を
考慮した塩基度となっており、又炭素が飽和に近い条件
を維持しながら、約１４００℃の低温で高いＭｎ歩留を
得る精錬方法である。(1) The converter blow-off condition at this time is usually 1600
°C to 1700 °C, C amount in I 0.05 to 0.50%
, Slag T, Fel O~25%, basicity 3.5~5.
0, and the basicity is determined by considering the timing of adding Mn ore into the converter and the amount of slag.Also, while maintaining conditions close to carbon saturation, a high Mn yield can be achieved at a low temperature of approximately 1400℃. It is a refining method to obtain.
（２）又、近年スクラップ発生量が増加してくるという
予想のもとに、鉄源としてスクラップのような冷鉄源を
溶解する方法が検討されており、その際熱源として固体
炭素物質を用いるものである。(2) In addition, in anticipation of an increase in the amount of scrap generated in recent years, methods of melting cold iron sources such as scrap are being considered as iron sources, and in this case, solid carbon materials are used as the heat source. It is something.
これに関するものとして特開昭６１−２２７１１９号公
報に、２基以上の転炉を用い、一つの転炉内で冷鉄源を
熔解して溶鉄を得ると共に、他の転炉において、従来の
製鋼精錬を行なう技術が開示されている。Regarding this, Japanese Patent Application Laid-Open No. 61-227119 discloses that two or more converters are used, one converter melts a cold iron source to obtain molten iron, and the other converter melts a cold iron source to obtain molten iron. A technique for performing refining is disclosed.
（３）又、特開昭６２−４７４１７号公報には、一つの
反応容器で溶解、製鋼精錬を行なうが、脱Ｓ、脱Ｎを促
進するために、スラグ中の塩基度を１．２以上に確保す
ること、あるいは溶鉄中のＣを２．０％以上とすること
などの報告がなされている。(3) Also, in JP-A-62-47417, melting and steelmaking refining are performed in one reaction vessel, but in order to promote de-S and de-N, the basicity of the slag is set to 1.2 or more. It has been reported that carbon content in the molten iron should be kept at 2.0% or more.
（発明が解決しようとする問題点）
以上記したように、スクランプ、・還元鉄などの固体鉄
源を、炭素物質を用いて転炉内において溶解するという
報告は多数見られるが、前記（１）の方法は、溶鋼を対
象としており、後述の本発明のような溶銑を対象とする
ものとは異なり、そのため、吹止温度、スラグＴ、Ｆｅ
、塩基度など操業条件が大きく異なる。(Problems to be Solved by the Invention) As mentioned above, there are many reports on melting solid iron sources such as scrap and reduced iron in a converter using carbon materials. ) is aimed at molten steel, and is different from the method of the present invention, which will be described later, which deals with molten pig iron.
, operating conditions such as basicity vary greatly.
又（２）の方法は、固体鉄中のＭｎに関する考慮は払わ
れていない。Furthermore, in the method (2), no consideration is given to Mn in solid iron.
更に、（３）の方法は、固体鉄中のＭｎを高く歩留らせ
るという発想はなく、かつ、吹酸速度を制御して、溶鉄
とスラグのＭｎ分配比、あるいは溶鉄中のｃｌ、さらに
はスラグ中Ｔ、Ｆｅを制御するという技術的発想はない
。Furthermore, method (3) does not have the idea of increasing the yield of Mn in solid iron, and controls the blowing acid rate to control the Mn distribution ratio between molten iron and slag, or the Cl in molten iron. There is no technical idea to control T and Fe in the slag.
従って、従来技術は、固体炭素物質を用いて固体鉄源を
溶解することに主眼があり、精錬については炭材からの
Ｓ、あるいはＮのピンクアップの問題から脱Ｓ精錬、脱
Ｎ精錬に適正な精錬条件を確保することが考慮されてい
るのみである。またＭｎについては、従来の高炉溶銑あ
るいは、固体鉄源を主原料とする近年の方法においても
、製鋼精錬、つまり脱炭精錬においてＭｎ鉱石を添加し
、溶鉄中の炭素あるいは固体炭素物質の添加によって還
元精錬することが主流であり、固体鉄源中のＭｎを効率
よく金属Ｍｎ源として得る方法は皆無である。Therefore, the main focus of the conventional technology is to melt solid iron sources using solid carbon materials, and regarding refining, it is suitable for de-S refining and de-N refining due to the problem of pink-up of S or N from carbonaceous materials. Only consideration is given to ensuring suitable refining conditions. Regarding Mn, even in recent methods that use conventional blast furnace hot metal or solid iron sources as main raw materials, Mn ore is added during steel refining, that is, decarburization refining, and carbon in the molten iron or solid carbon material is added. Reduction refining is the mainstream, and there is no method for efficiently obtaining Mn in a solid iron source as a metal Mn source.
特に固体鉄源を主原料として、２基以上の転炉を活用し
ての熔解精錬では、溶解精錬後の出鋼排滓により、他炉
へ溶鉄のめが装入されるために、酸化損失したＭｎは、
はぼ全量廃棄される。そのため、脱炭精錬炉での還元回
収も不可能な事から、溶解精錬炉でのＭｎの酸化ロスを
極小にすることが肝要である。In particular, in melting and refining that uses solid iron as the main raw material and utilizes two or more converters, oxidation loss occurs because molten iron is charged into another furnace from the tapped slag after melting and refining. Mn is
The entire amount is discarded. Therefore, since reduction and recovery in the decarburization refining furnace is also impossible, it is important to minimize the oxidation loss of Mn in the melting and refining furnace.
（問題点を解決するための手段）
本発明は、前記の状況に鑑みなされたもので、送酸速度
、溶銑撹拌力、溶鉄中のＣ量を考慮した指標により送酸
速度を決定し、溶鉄中のＣ量、スラグ中Ｔ、Ｆｅ濃度を
制御するものであり、その結果、固体鉄源中のＭｎを高
い歩留で得ることができるものである。(Means for Solving the Problems) The present invention was made in view of the above-mentioned situation, and determines the oxygen feeding rate based on an index that takes into consideration the oxygen feeding rate, the hot metal stirring force, and the amount of C in the molten iron. The amount of C in the slag, T, and Fe concentration in the slag are controlled, and as a result, Mn in the solid iron source can be obtained at a high yield.
本発明においては、反応容器の大きさ、固体鉄源のサイ
ズ、吹酸方法の差（上吹き、底吹き、上底吹き）等に関
係なく、溶鉄中の（％Ｃ〕と、撹拌力と、吹酸速度を組
み合わせた指標により吹酸速度を制御卸し、溶鉄中の〔
％Ｃ〕、スラグ中Ｔ、Ｆｅを適正範囲に制御する。同時
にスラグ塩基度、精錬温度を生石灰、軽焼Ｆロマイトの
ような副材の添加量及びヒートバランスから設定し、高
位なＭｎ歩留りを得る方法である。In the present invention, regardless of the size of the reaction vessel, the size of the solid iron source, the difference in acid blowing method (top blowing, bottom blowing, top and bottom blowing), etc., the (%C) in molten iron and the stirring power The rate of blowing acid is controlled using an index that combines the rate of blowing acid.
%C], T and Fe in the slag are controlled within appropriate ranges. At the same time, the basicity of the slag and the refining temperature are set based on the amount of additives such as quicklime and lightly calcined F lomite, and the heat balance to obtain a high Mn yield.
第１図は、Ｍｎ分配比（％Ｍｎ０）／ （％Ｍｎ）と溶
鉄中〔％Ｃ〕の関係を表わし、吹止め時において溶鉄中
の炭素濃度が３．８％未満になるとＭｎ分配比が象、激
に大きくなる。即ち、Ｍｎの酸化ロスが大きくなること
から吹止め時の溶鉄中〔％Ｃ〕は３．８％以上とする必
要がある。Figure 1 shows the relationship between the Mn distribution ratio (%Mn0)/(%Mn) and [%C] in the molten iron. Elephants grow very large. That is, since the oxidation loss of Mn becomes large, the [%C] in the molten iron at the time of blow-stopping needs to be 3.8% or more.
第２図は、Ｍｎ分配比とスラグ中（％Ｔ、Ｆｅ）の関係
を表わし、吹止め時において、スラグ中〔χＴ、Ｆｅ）
が２．０％を超えると急激にＭｎ分配比が大きくなり、
酸化ロスが大となるので吹止め時のスラグ中〔％Ｔ、
Ｆｅ ）は２．０％以下とする必要がある。Figure 2 shows the relationship between the Mn distribution ratio and the slag (%T, Fe).
When exceeds 2.0%, the Mn distribution ratio increases rapidly,
Since the oxidation loss becomes large, the slag [%T,
Fe ) needs to be 2.0% or less.
冶金的には、上記吹止め時の溶鉄中〔％Ｃ〕とスラグ中
Ｔ、Ｆｅは独立の因子ではなく、〔％Ｃ〕が３．８％未
満となると溶鉄中の酸素ポテンシャルが増加し、その結
果、それと平衡するスラグ中の酸素ポテンシャルＦｅＯ
は高くなる。制御因子としては、溶鉄中〔％Ｃ〕を調整
する事の方が容易であるが、スラグを還元剤により強制
的に還元することも技術的に可能であり、両方の因子を
制御因子として設定した。Metallurgically, [%C] in the molten iron at the time of blow-stopping and T and Fe in the slag are not independent factors; when [%C] is less than 3.8%, the oxygen potential in the molten iron increases, As a result, the oxygen potential in the slag that is in equilibrium with it, FeO
becomes higher. As a control factor, it is easier to adjust [%C] in molten iron, but it is also technically possible to forcefully reduce slag with a reducing agent, and both factors are set as control factors. did.
一方、溶鉄中〔％Ｃ〕を安定して３．８％以上とするた
めには、固体鉄源を添加する前の溶鉄がＣ５０，８％と
なっていることが必須の条件であるが更に、吹酸速度を
考慮する必要がある。つまり、固体鉄源を溶解するため
の熱源である固体炭素物質は、連続的に投入されるため
、溶鉄中への浸炭も含め炭素物質中のＣの反応速度に見
合った酸素のみを供給すれば、Ｃ以外の元素、特にＭｎ
の酸化ロスを減少することができる。更に、ＣＯの二次
燃焼を意図的に高める場合、炉内での酸素ポテンシャル
を高めるために必要な酸素量を付加する必要がある。そ
の結果、次に示す（１）式に従って与えられる酸素供給
速度を保持することが重要である。On the other hand, in order to stably maintain [%C] in molten iron at 3.8% or more, it is an essential condition that the molten iron has a carbon content of 50.8% before adding the solid iron source. , it is necessary to consider the acid blowing rate. In other words, since the solid carbon material, which is the heat source for melting the solid iron source, is continuously introduced, it is necessary to supply only oxygen that is commensurate with the reaction rate of C in the carbon material, including carburization into the molten iron. , elements other than C, especially Mn
oxidation loss can be reduced. Furthermore, when intentionally increasing the secondary combustion of CO, it is necessary to add an amount of oxygen necessary to increase the oxygen potential within the furnace. As a result, it is important to maintain the oxygen supply rate given by equation (1) shown below.
Ｖｏｚ＝ ０．９３３Ｗｃ ＋ＶＰＣ−−−（１）式コ
コア０．９３３ハＣ＋ ％ｏｚ −＋ ｃｏ 反応ニ
ヨリＣ源１ ｋｇを燃焼させるのに必要な化学当量とし
ての酸素量（Ｎｎ（）である。ＶＰＣは二次燃焼として
必要な酸素量（Ｎｎ（）である。この定義式以上の酸素
を吹酸した場合には溶鉄中〔％Ｃ〕を３．８％以上に保
持することは不可能であり、結果としてＭｎＯ濃度も高
く、高Ｍｎ歩留を得ることはできない。Voz=0.933Wc +VPC---Formula (1) Cocoa 0.933C+ %oz -+ co The amount of oxygen (Nn()) as a chemical equivalent required to burn 1 kg of reaction Niyori C source. VPC is the amount of oxygen (Nn()) required for secondary combustion.If oxygen is blown in an amount greater than this definition, it is impossible to maintain [%C] in the molten iron at 3.8% or more. As a result, the MnO concentration is also high, making it impossible to obtain a high Mn yield.
また当該送酸速度により精錬し、吹止時の溶鉄中〔％Ｃ
〕が３．８％未満番ごなった場合には、固体炭素物質を
、望ましくは底部から粉状として添加し、所定の範囲に
入るように加炭、撹拌精錬する。In addition, the molten iron [%C
] is less than 3.8%, solid carbon material is added, preferably in the form of powder from the bottom, and carburized and stirred and refined so that it falls within a predetermined range.
その結果、スラグ中のＦｅＯが還元低下すると同時にＭ
ｎＯも還元され、所定のＭｎ分配比を得ることが可能で
ある。As a result, FeO in the slag is reduced and at the same time M
nO is also reduced, making it possible to obtain a predetermined Mn distribution ratio.
スラグ中の塩基度を高くすれば、Ｍｎ分配比が小さくな
ることは冶金原理として公知の事実であるが、ＣａＯ添
加量の増加に伴ないスラグ量が増加し、Ｍｎ歩留りとし
ては不利になる。しかし、逆に塩基度が１．０未満にな
ると耐火物溶損が激しく進行することから１．０以上は
確保する必要がある。第３図に塩基度と経済評価の関係
を示す。経済評価は耐火物コストとＭｎ歩留りを考慮し
た評価であり、第３図から判るように塩基度Ｖ−ＣａＯ
／ＳｉＯ□を１．０乃至２．０とするのが良い。It is a well-known metallurgical principle that increasing the basicity in slag reduces the Mn distribution ratio, but as the amount of CaO added increases, the amount of slag increases, which is disadvantageous in terms of Mn yield. However, on the contrary, if the basicity is less than 1.0, the erosion of the refractory will proceed rapidly, so it is necessary to ensure that the basicity is 1.0 or more. Figure 3 shows the relationship between basicity and economic evaluation. The economic evaluation is an evaluation that takes refractory cost and Mn yield into consideration, and as can be seen from Figure 3, basicity V-CaO
/SiO□ is preferably set to 1.0 to 2.0.
精錬温度は、高い程Ｍｎ分配比は小さくなる（Ｍｎ歩留
りは高くなる）事も冶金原理として公知であるが、精錬
温度が高い程耐火物溶損が激しくなることから、上限が
あり、また溶解精錬後の脱Ｓあるいは脱Ｐ精錬といった
溶銑予備処理等の後工程の処理のために必要な温度確保
から最低温度は決定される。精錬温度は、Ｍｎ分配比に
直接影響するだけでなく、スラグ中Ｔ、Ｆｅの値にも、
また撹拌力にも影響し、その変動は少なくないが、経済
的効果とプロセス制約から経験的に１３８０℃乃至１４
５０℃とするのが最適であることを見出した。It is a well-known metallurgical principle that the higher the refining temperature, the smaller the Mn distribution ratio (the higher the Mn yield). The minimum temperature is determined by ensuring the temperature required for subsequent processes such as hot metal pretreatment such as de-S or de-P refining after refining. The refining temperature not only directly affects the Mn distribution ratio, but also affects the values of T and Fe in the slag.
It also affects the stirring power, and although it fluctuates quite a bit, it has been empirically shown that from 1380℃ to 14℃ due to economic effects and process constraints.
It has been found that a temperature of 50°C is optimal.
以上のように、スラグ中塩基度と精錬温度は主として経
済的な観点からの制約条件であり、むしろ本発明におい
ては前述の塩基度及び温度の範囲内で吹き止め時の溶鉄
中〔％Ｃ〕とスラグ中Ｔ、Ｆｅ濃度を（１）式の送酸速
度に従うことにより適正な範囲に制御し、高Ｍｎ歩留り
を得ることができる。As mentioned above, the basicity in slag and the refining temperature are constraints mainly from an economic point of view, and rather, in the present invention, the basicity in the slag and the refining temperature are within the range of the basicity and temperature described above. A high Mn yield can be obtained by controlling the T and Fe concentrations in the slag to an appropriate range by following the oxygen delivery rate of equation (1).
（実施例）
前チヤージ溶製後、約１８０ｔの溶銑がベースメタルと
して残存している上底吹き転炉に１６５ｔのスクラップ
を２バツクに分けて装入した。先ず、スラグの残片、ク
ロップ屑を含む８２ｔのスクラップを、１３９０℃、Ｃ
＝４．０５％、Ｍｎ＝０．３４％の溶銑に装入し、同時
にＣａＯを０．９Ｌ、軽焼ドロマイトを１．３を装入し
た。上吹きランスから３０．０００ Ｎｒｒｆ／ｈｒの
０□を吹精しながら底吹き１２本の三重管ノズルの内管
からＮ２ガス（２７ＯＮｒｒｆ／ｈｒ・本）をキャリア
ーとして石炭粉を８０ ｋｇ／ｍｉｎの速度で加炭した
。三重管ノズルの中管からは、空気と純酸素の混合ガス
（０□ガス換算１１５０ Ｎｒｄ／ｈｒ・本）を吹き込
み、外管からは、ノズルの冷却ガスとしてＬＰＧを４５
Ｎｒｒｒ／ｈｒ・本吹き込んだ。(Example) After pre-charge melting, 165 tons of scrap was divided into two batches and charged into a top-bottom blowing converter in which about 180 tons of hot metal remained as base metal. First, 82 tons of scrap including slag residue and crop waste was heated at 1390°C.
= 4.05%, Mn = 0.34%, and at the same time, 0.9 L of CaO and 1.3 L of light calcined dolomite were charged. While blowing 0□ of 30,000 Nrrf/hr from the top blowing lance, coal powder was blown at 80 kg/min using N2 gas (27ONrrf/hr/piece) as a carrier from the inner pipe of 12 bottom blowing triple tube nozzles. Recarburized at high speed. A mixed gas of air and pure oxygen (0 □ gas equivalent: 1150 Nrd/hr/piece) is blown into the middle tube of the triple tube nozzle, and 45 LPG is blown into the outer tube as a cooling gas for the nozzle.
Nrrr/hr・I wrote the book.
上記の設定条件で約２４分間吹錬した結果、１４０６”
ＣＸＣ＝４．０８％、〔％Ｍｎ）−０，３５％、スラグ
中（％Ｍｎ０） −２，２％の溶銑を得た。Ｍｎ分配比
は６．２、計算Ｍｎ歩留りは７０％であり、０□供給速
度は２．１Ｎｎ（ハ・ｍｉｎであった。引き続き８３ｔ
の同様のスクラップをＣａＯ１，Ｏｔ、軽焼ドロマイト
１．４ｔと同時に装入し、１ハツク目の上底吹き条件と
全く同じ条件でスクラップ溶解精錬を２５分間実施した
結果、吹止め１４０８℃，Ｃ＝３．９９％、Ｍｎ＝０．
３８％、Ｐ ＝０．０４６％、Ｓ ＝０．０２２％の３
４０ｔの溶銑を得た。スラグ中のＭｎＯ濃度は２．５％
、ＣａＯ＝ ４３％、ＳｉＯ，−３１％であり、Ｍｎ分
配比−６．６、塩基度１．４、送酸速度は２．１ Ｎ
ｎ（３／ｔ−ｍｉｎであった。いずれも条件を満足して
おり、最終的なスクラップ中のＭｎ歩留りは７２％であ
った。As a result of blowing for about 24 minutes under the above setting conditions, the result was 1406"
Hot metal with CXC=4.08%, [%Mn) -0.35%, and (%Mn0) -2.2% in slag was obtained. The Mn distribution ratio was 6.2, the calculated Mn yield was 70%, and the 0□ supply rate was 2.1 Nn (ha min.
Similar scrap was charged at the same time as CaO1, Ot, and 1.4 tons of light calcined dolomite, and scrap melting and refining was carried out for 25 minutes under exactly the same conditions as the top and bottom blowing conditions of the first hatch. =3.99%, Mn=0.
38%, P = 0.046%, S = 0.022% 3
40 tons of hot metal was obtained. MnO concentration in slag is 2.5%
, CaO = 43%, SiO, -31%, Mn distribution ratio -6.6, basicity 1.4, oxygen delivery rate 2.1 N
n (3/t-min). All conditions were satisfied, and the final Mn yield in the scrap was 72%.
当該溶銑のうち１７２ｔが出銑され、溶銑予備処理スタ
ンドで溶銑を当り５．０ ｋｇのＣａＯと１．２ ｋｇ
のＩＶドロスを添加し約８分の脱Ｓ精錬が実施され、〔
％Ｓ］を０．０２２％から０．０１４％に低減した後、
通常転炉に装入され脱炭精錬が施された。以上の精錬過
程における溶銑成分温度、スラグ中代表成分、操業条件
等を第１表に示す。また上記の精錬結果として高価なＦ
ｅＭｎを約５ｋｇ／ｌ−ｓ削減することができた。172 tons of the hot metal was tapped, and 5.0 kg of CaO and 1.2 kg of hot metal were extracted at the hot metal pretreatment stand.
IV dross was added and de-S refining was carried out for about 8 minutes.
%S] from 0.022% to 0.014%,
Usually, it is charged into a converter and decarburized and refined. Table 1 shows the hot metal component temperature, representative components in slag, operating conditions, etc. in the above refining process. In addition, as a result of the above refining process, expensive F
It was possible to reduce eMn by about 5 kg/ls.
（発明の効果）
以上実施例でも明らかなように、固体鉄源であるスクラ
ンプを固体炭素物質である石炭粉を熱源として溶解する
際に、溶鉄中の［％Ｃ］と上底吹きガスによる撹拌力と
吹酸速度を考慮に入れた精錬制御指標を所定の範囲に制
御することにより、スクラップ中のＭｎを７０％以上の
高歩留りで溶鉄中に保持することが可能となり、高価な
ＦｅＭｎ合金鉄を削減することができた。(Effects of the Invention) As is clear from the above examples, when melting the solid iron source, ie, the scrap, using coal powder, which is the solid carbon material, as the heat source, the [%C] in the molten iron and the stirring by the top and bottom blowing gas By controlling the refining control index that takes force and acid blowing rate into consideration, it is possible to retain Mn in scrap in molten iron with a high yield of 70% or more, and it is possible to maintain the Mn in scrap in molten iron, which is an expensive FeMn alloy ferro. was able to reduce.
第１図は、Ｃ量とＭｎ分配比の関係を示す図、第２図は
、スラグ中Ｔ、 ＦｅとＭｎ分配比の関係を示す図、第
３図は、塩基度と経済指標の関係を示す図である。
特許出願人 新日本製鐵株式会社
’Ｑ ３ ミ ′＞）（’＃％
）／（０”＃％）
イ伯−侭
〔ｌｔＨ％〕／（０私悩）
ｚ’ｈｖ 云Figure 1 shows the relationship between C content and Mn distribution ratio, Figure 2 shows the relationship between T, Fe and Mn distribution ratio in slag, and Figure 3 shows the relationship between basicity and economic indicators. FIG. Patent applicant: Nippon Steel Corporation 'Q3 Mi'>) ('#%
) / (0”#%) I Haku - W [ltH%] / (0 private worries) z'hv yun
Claims (1)
際、精錬終了時の溶鉄中Ｃ濃度を３．８％以上、スラグ
中Ｔ．Ｆｅを２．０％以下、スラグ塩基度を１．０〜２
．０、吹止め温度を１３８０℃〜１４５０℃とすると共
に吹酸速度を下記（１）式を満足するよう操業すること
を特徴とする高Ｍｎ歩留りを得る固体鉄源溶解法。 Ｖ＿ｏ＿２≒０．９３３Ｗ＿ｃ＋Ｖ＿ｐ＿ｃ………（１
）式ここでＶ＿ｏ＿２：送酸速度（Ｎｍ＾３／ｔ−ｍｉ
ｎ）Ｗ＿ｃ：炭素物質の添加速度（ｋｇ／ｔ−ｍｉｎ）
Ｖ＿ｐ＿ｃ：二次燃焼用の酸素（Ｎｍ＾３／ｔ−ｍｉｎ
）[Claims] When melting a solid iron source in a reaction vessel using a carbon material as a heat source, the C concentration in the molten iron at the end of refining is set to 3.8% or more, and the T. Fe 2.0% or less, slag basicity 1.0-2
．． 0. A solid iron source melting method for obtaining a high Mn yield, which is characterized in that the blowing temperature is set at 1380° C. to 1450° C. and the blowing acid rate is operated so as to satisfy the following formula (1). V_o_2≒0.933W_c+V_p_c……(1
) formula where V_o_2: Oxygen delivery rate (Nm^3/t-mi
n) W_c: Addition rate of carbon material (kg/t-min)
V_p_c: Oxygen for secondary combustion (Nm^3/t-min
)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63012583A JPH01188615A (en) | 1988-01-25 | 1988-01-25 | Solid iron source melting method for obtaining high mn yield |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63012583A JPH01188615A (en) | 1988-01-25 | 1988-01-25 | Solid iron source melting method for obtaining high mn yield |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01188615A true JPH01188615A (en) | 1989-07-27 |
| JPH0480087B2 JPH0480087B2 (en) | 1992-12-17 |
Family
ID=11809376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63012583A Granted JPH01188615A (en) | 1988-01-25 | 1988-01-25 | Solid iron source melting method for obtaining high mn yield |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01188615A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5655528A (en) * | 1979-10-09 | 1981-05-16 | Nippon Steel Corp | Melt refining method for metal |
-
1988
- 1988-01-25 JP JP63012583A patent/JPH01188615A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5655528A (en) * | 1979-10-09 | 1981-05-16 | Nippon Steel Corp | Melt refining method for metal |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0480087B2 (en) | 1992-12-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5954551B2 (en) | Converter steelmaking | |
| US3323907A (en) | Production of chromium steels | |
| US4533385A (en) | Method for producing metals, such as molten pig iron, steel pre-material and ferroalloys | |
| JPS6250545B2 (en) | ||
| US4090869A (en) | Process of manufacturing alloy steels in a continuously charged arc furnace | |
| JP3774674B2 (en) | Method for producing low nitrogen-containing chromium molten steel | |
| JPH01188615A (en) | Solid iron source melting method for obtaining high mn yield | |
| US3234011A (en) | Process for the production of steel | |
| JP5949627B2 (en) | Method of refining hot metal in converter | |
| JPH0471965B2 (en) | ||
| JP2005068533A (en) | Method for dephosphorizing molten pig iron | |
| JPH01252715A (en) | Method for operating iron bath type smelting reduction furnace | |
| JPS6152208B2 (en) | ||
| JPS62116712A (en) | Melting and smelting vessel having splash lance | |
| JPH08209228A (en) | Steel making method | |
| JP2727627B2 (en) | Manufacturing method of hot metal for high alloy steel | |
| JP3718263B2 (en) | Hot metal pretreatment method | |
| SU729251A1 (en) | Method of steel casting in hearth steel-melting set | |
| JPH01195211A (en) | Method for melting and reducing iron oxide | |
| JPH11158525A (en) | Method for melting nickel-contining steel | |
| JPH0633127A (en) | Method for decarburizing chromium-containing molten iron | |
| JPS6123244B2 (en) | ||
| JPH032312A (en) | Production of low-phosphorus pig iron | |
| JPH01195214A (en) | Operation of iron bath type melting and reducing furnace | |
| JPS5891114A (en) | Refining process of steel containing ni |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081217 Year of fee payment: 16 |
|
| EXPY | Cancellation because of completion of term | ||
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081217 Year of fee payment: 16 |