JPH11100608A - Method for desiliconizing and desulfurizing molten iron - Google Patents
Method for desiliconizing and desulfurizing molten ironInfo
- Publication number
- JPH11100608A JPH11100608A JP26163497A JP26163497A JPH11100608A JP H11100608 A JPH11100608 A JP H11100608A JP 26163497 A JP26163497 A JP 26163497A JP 26163497 A JP26163497 A JP 26163497A JP H11100608 A JPH11100608 A JP H11100608A
- Authority
- JP
- Japan
- Prior art keywords
- slag
- iron oxide
- desiliconization
- hot metal
- 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.)
- Pending
Links
Landscapes
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、溶銑の脱珪・脱硫
方法に関する。TECHNICAL FIELD The present invention relates to a method for desiliconizing and desulfurizing hot metal.
【０００２】[0002]
【従来の技術】高炉で製造される溶銑には通常珪素が
０．２〜０．６％、硫黄が０．０２〜０．０４％含有さ
れている。これらの成分を転炉で脱リン脱炭精錬する前
に除去する溶銑予備処理が広く実施されている。2. Description of the Related Art Hot metal manufactured in a blast furnace usually contains 0.2 to 0.6% of silicon and 0.02 to 0.04% of sulfur. Hot metal pretreatment for removing these components before dephosphorization and decarburization in a converter is widely practiced.
【０００３】下記式（１）、（２）に示すように、脱珪
反応は鉄酸化物（鉄鉱石、ミルスケール等）もしくは気
体酸素を溶銑に添加することにより進行する。尚、[
] は溶銑中の成分を、（ ）はスラグ中の成分をそれ
ぞれ示す。As shown in the following formulas (1) and (2), the desiliconization reaction proceeds by adding iron oxide (iron ore, mill scale, etc.) or gaseous oxygen to hot metal. still,[
] Indicates the components in the hot metal, and () indicates the components in the slag.
【０００４】 ［Ｓｉ］＋（２／３Ｆｅ2 Ｏ3 ）＝［４／３Ｆｅ］＋（ＳｉＯ2 ）（１） ［Ｓｉ］＋Ｏ2 ＝（ＳｉＯ2 ） （２） 上記脱珪反応をより速くするには、反応系（左辺）の酸
素ポテンシャルがより高いことが必要である。[Si] + (2 / 3Fe 2 O 3 ) = [4 / 3Fe] + (SiO 2 ) (1) [Si] + O 2 = (SiO 2 ) (2) Speed up the desiliconization reaction Requires that the oxygen potential of the reaction system (left side) be higher.
【０００５】下記式（３）に示す脱硫反応はＣａＯを溶
銑に添加することにより進行する。脱硫反応をより速く
するには、反応系（左辺）の酸素ポテンシャルをより低
くすることが必要である。The desulfurization reaction represented by the following formula (3) proceeds by adding CaO to hot metal. To make the desulfurization reaction faster, it is necessary to lower the oxygen potential of the reaction system (left side).
【０００６】 ［Ｓ］＋（ＣａＯ） =（ＣａＳ）＋ １／２Ｏ2 （３） 以上のように、脱珪と脱硫を同時に進行させることは原
理的に難しく、従来脱珪スラグを除去した後脱硫処理し
ていた。[S] + (CaO) = (CaS) + O 2 (3) As described above, it is theoretically difficult to simultaneously advance desiliconization and desulfurization. Conventionally, after removing desiliconized slag, Had been desulfurized.
【０００７】特開平６−２７１９２０号公報には、溶銑
中の珪素、硫黄を除去すると同時に溶銑にマンガンの添
加をする方法が開示されている。しかし、この方法で
は、次の問題があり、改善が求められていた。Japanese Patent Application Laid-Open No. 6-271920 discloses a method of removing silicon and sulfur in hot metal and simultaneously adding manganese to the hot metal. However, this method has the following problems, and improvements have been demanded.
【０００８】（１）スラグ中酸化マンガンの含有量が多
くなり、スラグの融点が上がるため、螢石（ＣａＦ2 含
有物質）を多量に必要とすること。 （２）螢石を多量に使用するため、耐火物の損傷が大き
いこと。(1) Since the content of manganese oxide in slag increases and the melting point of slag increases, a large amount of fluorite (a CaF 2 -containing substance) is required. (2) The use of a large amount of fluorite causes significant damage to refractories.
【０００９】（３）螢石を多量に使用した場合でも酸化
マンガンと溶銑中珪素との反応速度が遅く、処理に長時
間を要すること。 （４）原料としてマンガン鉱物（マンガン鉱石、鉄マン
ガン鉱石）を使用するので、低マンガン規格鋼を生産で
きないこと。(3) Even when a large amount of fluorite is used, the reaction rate between manganese oxide and silicon in the hot metal is slow, and the treatment requires a long time. (4) Since manganese minerals (manganese ore, iron manganese ore) are used as raw materials, low manganese standard steel cannot be produced.
【００１０】（５）使用マンガン鉱物中は、一般的に脈
石成分が多いため、生成スラグ量が多くなり、スラグ処
理面での処理コストが高いこと等 更に、この方法の処理時間は約３０分であり、前後工程
の現状ピッチから許容される処理時間（約１５分）を大
幅に超過し短縮化が必要であった。０．００５％以下の
低硫黄銑の低硫黄のニーズも高まってきており、一層の
効率的な方法が必要であった。(5) The manganese minerals used generally contain a large amount of gangue components, so that the amount of slag produced is large and the cost of treating slag is high. Further, the processing time of this method is about 30 minutes. Minutes, which greatly exceeds the processing time (about 15 minutes) allowed from the current pitch of the preceding and succeeding processes, and it is necessary to reduce the processing time. The need for low sulfur pig iron of 0.005% or less has been increasing, and a more efficient method was needed.
【００１１】[0011]
【発明が解決しようとする課題】本発明の目的は、Ｃａ
Ｆ2 使用を最小限（５％未満）に抑えて効率的に溶銑の
脱珪・脱硫（目標溶銑中硫黄濃度：０．００５％以下）
をする処理方法を提供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a Ca
Efficient desiliconization and desulfurization of hot metal by minimizing the use of F 2 (less than 5%) (target sulfur concentration in hot metal: 0.005% or less)
To provide a processing method for performing
【００１２】[0012]
【課題を解決するための手段】本発明は、下記の知見を
もとに完成されたものである。 （１）マンガン鉱物に比べ融点が低い鉄酸化物（鉄鉱
石、ミルスケール、焼結鉱等）を脱珪剤として使用する
ことにより融点降下剤のＣａＦ2 の使用を抑えることが
できる。The present invention has been completed based on the following findings. (1) By using an iron oxide (iron ore, mill scale, sinter or the like) having a lower melting point than that of a manganese mineral as a desiliconizing agent, it is possible to suppress the use of CaF 2 as a melting point depressant.
【００１３】（２）脱炭反応の優先領域である溶銑中珪
素濃度が０. １％未満の領域を避け、０. １％以上のレ
ベルで脱珪することにより脱珪反応を速くすることがで
きる。(2) It is possible to speed up the desiliconization reaction by avoiding a region where the silicon concentration in the hot metal is less than 0.1%, which is a priority region of the decarburization reaction, and desiliconizing at a level of 0.1% or more. it can.
【００１４】（３）スラグの流動性が良好であれば、酸
化鉄の反応効率を上げることができ、スラグ中の酸化鉄
濃度を速やかに低下させることができる。この結果、酸
素ポテンシャルの低いスラグ状態で後続の脱硫反応を進
ませることができ、脱珪・脱硫の全体処理時間の短縮化
ができる。(3) If the fluidity of the slag is good, the reaction efficiency of the iron oxide can be increased, and the iron oxide concentration in the slag can be rapidly reduced. As a result, the subsequent desulfurization reaction can proceed in a slag state having a low oxygen potential, and the overall processing time for desiliconization and desulfurization can be reduced.
【００１５】（４）脱珪期末期のスラグ中酸化鉄濃度(
Ｆｅ換算値) を５％以下にまで低下すれば、その後にＣ
ａＯ、ＣａＦ2 を適量追加することにより溶銑中硫黄濃
度を０. ００５％以下にまで低下できる （５）Ａｌの添加はスラグ中の鉄酸化物を還元する手段
として有効であるが、添加時期は、スラグ中酸化鉄濃度
が鉄換算で５重量％以下の時点以降が効果的である。Ａ
ｌの添加により、さらにスラグ中酸化鉄濃度がさらに低
下し、脱硫反応速度を速くできる。添加するＡｌは、Ａ
ｌ灰等のＡｌを含む物質であり、必ずしも純金属のＡｌ
でなくてもよい。 （６）攪拌下、脱珪・脱硫処理を実施すると各反応が一
層速くできる。(4) Iron oxide concentration in slag at the end of the desiliconization period (
Fe conversion value) to 5% or less, then C
By adding appropriate amounts of aO and CaF 2 , the sulfur concentration in the hot metal can be reduced to 0.005% or less. (5) The addition of Al is effective as a means for reducing iron oxide in slag, It is effective when the iron oxide concentration in the slag is 5% by weight or less in terms of iron. A
By the addition of 1, the iron oxide concentration in the slag is further reduced, and the desulfurization reaction rate can be increased. Al to be added is A
It is a substance containing Al such as ash, and is not necessarily pure metal Al
It does not have to be. (6) If desiliconization / desulfurization treatment is carried out under stirring, each reaction can be further accelerated.
【００１６】以上の知見から本発明の構成は次に示すよ
うになる。 （１）：攪拌下、溶銑中珪素濃度が０. １％以上の溶銑
に、鉄酸化物と、ＣａＯと、ＣａＦ2 を添加し、スラグ
中酸化鉄濃度がＦｅ換算値で５％以下とする脱珪を主と
する第一工程と、その後、攪拌下、ＣａＯとＣａＦ2 を
含む脱硫剤を添加する脱硫を主とする第二工程とから構
成される。 （２）：第二工程に先立って、Ａｌを添加する。From the above findings, the configuration of the present invention is as follows. (1): Under stirring, iron oxide, CaO, and CaF 2 are added to hot metal having a silicon concentration of 0.1% or more in the hot metal to make the iron oxide concentration in the slag 5% or less in terms of Fe. The first step mainly includes desiliconization, and the second step mainly includes desulfurization in which a desulfurizing agent containing CaO and CaF 2 is added under stirring. (2): Prior to the second step, Al is added.
【００１７】[0017]
【発明の実施の形態】溶銑中の珪素濃度が０. １％以上
の条件下、マンガン鉱物に比べ融点が低い鉄酸化物（鉄
鉱石、ミルスケール、焼結鉱等）用いて効率的に脱珪し
た後、脱硫処理を実施する方法である。BEST MODE FOR CARRYING OUT THE INVENTION Under the condition that the silicon concentration in hot metal is 0.1% or more, iron oxide (iron ore, mill scale, sintered ore, etc.) having a melting point lower than that of manganese mineral is efficiently removed. This is a method of performing desulfurization treatment after siliconization.
【００１８】溶銑中珪素濃度が０. １％以上と規定した
のは、珪素濃度が０. １％未満の範囲では、脱炭反応が
優先反応になるため、脱珪速度が顕著に低下するからで
ある。The reason why the silicon concentration in the hot metal is specified to be 0.1% or more is that when the silicon concentration is less than 0.1%, the decarburization reaction becomes a preferential reaction, so that the desiliconization rate is significantly reduced. It is.
【００１９】本発明の特徴とするところは、脱珪処理時
のスラグ塩基度を極力低めとすることにより、スラグの
融点を下げて流動性を良好に保ち、しかも脱珪反応優先
領域にて反応させることにより、スラグ中の酸化鉄濃度
を速やかに低下させて、酸素ポテンシャルの低い状態で
後続の脱硫反応を効率良く進ませることにある。The feature of the present invention is that the slag basicity at the time of desiliconization treatment is made as low as possible, thereby lowering the melting point of slag and maintaining good fluidity, and furthermore, the reaction is performed in the desiliconization reaction priority region. By doing so, the concentration of iron oxide in the slag is rapidly reduced, and the subsequent desulfurization reaction proceeds efficiently with a low oxygen potential.
【００２０】本方法により脱珪期末期の酸化鉄濃度( Ｆ
ｅ換算値) を５％以下にまで低下すれば、その後にＣａ
Ｏ、ＣａＦ2 を適量追加することにより溶銑中硫黄濃度
を０. ００５％以下にまで低下できる。According to this method, the iron oxide concentration at the end of the desiliconization period (F
e converted value) to 5% or less, then Ca
By adding appropriate amounts of O and CaF 2 , the sulfur concentration in the hot metal can be reduced to 0.005% or less.
【００２１】Ａｌを添加するのは、スラグ中酸化鉄を還
元し、酸素ポテンシャルを低下させて脱硫反応をさらに
低硫黄レベルまで進ませるためである。Ａｌの添加は、
スラグ中酸化鉄濃度が鉄換算で５重量％以下の時点以降
が有効である。その理由は５％超えると脱珪反応が十分
進んでおらず、脱珪反応そのものを阻害するおそれがあ
るからである。The reason for adding Al is to reduce the iron oxide in the slag and reduce the oxygen potential to further advance the desulfurization reaction to a low sulfur level. The addition of Al
It is effective when the iron oxide concentration in the slag is 5% by weight or less in terms of iron. The reason is that if it exceeds 5%, the desiliconization reaction does not sufficiently proceed, and the desiliconization reaction itself may be inhibited.
【００２２】脱珪処理の末期にスラグ中酸化鉄濃度が５
％以下でＡｌを添加すると、酸化鉄濃度( Ｆｅ換算値)
を２％以下にまで速やかに低下でき、溶銑中の硫黄濃度
を０. ００２％以下にまで低減できる。At the end of the desiliconization treatment, the iron oxide concentration in the slag is 5
% Or less, if Al is added, iron oxide concentration (Fe equivalent value)
Can be quickly reduced to 2% or less, and the sulfur concentration in the hot metal can be reduced to 0.002% or less.
【００２３】脱珪効率をさらに向上させる方法を詳細に
検討した結果、以下の知見を得た。脱珪処理における望
ましいスラグ組成は、（１）０. ５≦塩基度( ＣａＯ/
ＳｉＯ2 重量比) ≦２. ０（２）ＣａＦ2 ＜５％であ
る。As a result of a detailed study of a method for further improving the desiliconization efficiency, the following findings were obtained. The desirable slag composition in the desiliconization treatment is as follows: (1) 0.5 ≦ basicity (CaO /
(SiO 2 weight ratio) ≦ 2.0 (2) CaF 2 <5%.
【００２４】塩基度の望ましい下限を０. ５としたの
は、０. ５未満であるとスラグ中のＳｉＯ2 活量が増加
して脱珪速度が低下し、しかも耐火物溶損量が極めて多
くなるおそれがあるからである。The reason why the lower limit of the basicity is preferably 0.5 is that if the basicity is less than 0.5, the SiO 2 activity in the slag increases, the desiliconization speed decreases, and the amount of refractory erosion extremely decreases. This is because there is a possibility that it will increase.
【００２５】塩基度の望ましい上限を２. ０としたの
は、２. ０を超えるとスラグの融点が上昇しスラグ中Ｃ
ａＦ2 濃度を５％以上としなければスラグの流動性を確
保できず、ＣａＯ添加量および高価なＣａＦ2 添加量が
増加することから媒溶剤コストが増加するおそれがある
からである。また、ＣａＦ2 添加量５％以上に増加する
と、前述のように耐火物の損傷が大きくなり安定操業が
困難となるおそれがある。The reason why the upper limit of the basicity is preferably set to 2.0 is that if the basicity exceeds 2.0, the melting point of the slag increases and the C in the slag increases.
Unless the aF 2 concentration is 5% or more, the fluidity of the slag cannot be secured, and the amount of CaO added and the amount of expensive CaF 2 added increase, so that the cost of the solvent may increase. Further, when the amount of CaF 2 added is increased to 5% or more, as described above, damage to the refractory may increase, and stable operation may be difficult.
【００２６】特開平６−２７１９２０号公報に記載の前
記マンガン鉱物を使用する場合、スラグの流動性を確保
するためにスラグ中ＣａＦ2 濃度を５〜３０％、望まし
くは１０〜２０％と高めなければならないが、本法のご
とく鉄酸化物を用いる場合には、スラグ中ＣａＦ2 濃度
を５％未満であっても脱珪反応を速やかに進行させるこ
とができる。この理由は、前記マンガン鉱物に比べ鉄酸
化物の融点が低いので、融点降下剤であるＣａＦ2 の添
加をそれほど必要としないからである。When the manganese mineral described in JP-A-6-271920 is used, the CaF 2 concentration in the slag must be increased to 5 to 30%, preferably 10 to 20% in order to secure the fluidity of the slag. However, when an iron oxide is used as in the present method, the desiliconization reaction can proceed promptly even if the CaF 2 concentration in the slag is less than 5%. The reason for this is that the melting point of iron oxide is lower than that of the manganese mineral, so that it is not necessary to add CaF 2 as a melting point depressant so much.
【００２７】鉄鉱石等の鉄酸化物、ＣａＯおよびＣａＦ
2 からなる脱珪剤は脱珪処理初期に一括添加しても良い
し、ＣａＯおよびＣａＦ2 のみ脱珪処理中に分割添加も
しくは連続添加しても良いが、２段添加の場合は脱珪初
期に形成されるスラグが低塩基度であるため低融点とな
り、溶銑中の珪素と反応し易くなり脱珪反応速度が速く
なる。その後は、滓化したスラグ中に、ＣａＯを分割添
加もしくは連続添加することにより、溶融スラグの塩基
度が徐々に上がり、スラグ中の酸化鉄の活量係数が増加
し、一方、ＳｉＯ2 の活量が低下し、溶銑中の珪素によ
る酸化鉄の還元反応すなわち脱珪反応が効率よく進行す
る。Iron oxides such as iron ore, CaO and CaF
2 may be added all at once in the early stage of the desiliconization treatment, or only CaO and CaF 2 may be added separately or continuously during the desiliconization process. Since the slag formed at a low basicity has a low melting point, it easily reacts with the silicon in the hot metal, and the desiliconization reaction rate is increased. Thereafter, the basicity of the molten slag is gradually increased by adding CaO to the slag in a divided or continuous manner, and the activity coefficient of iron oxide in the slag is increased, while the activity of SiO 2 is increased. As a result, the reduction reaction of iron oxide by silicon in the hot metal, that is, the desiliconization reaction proceeds efficiently.
【００２８】脱珪後に除滓をしてもよいが、除滓による
処理時間延長および熱ロスを避けるために除滓をしなく
てもよい。溶銑の攪拌法は、特に限定しないが、インペ
ラー方式の攪拌法が望ましく、例えば溶銑の脱硫処理に
広く使用されているＫＲ式の攪拌法が望ましい。脱珪の
ための酸素源として、酸化鉄のみならず、酸素ガスも使
用できる。Although deslagging may be carried out after desiliconization, deslagging may not be carried out in order to prolong the treatment time and to avoid heat loss. The method for stirring the hot metal is not particularly limited, but an impeller-type stirring method is preferable, and for example, a KR-type stirring method widely used for desulfurizing hot metal is preferable. As an oxygen source for desiliconization, not only iron oxide but also oxygen gas can be used.
【００２９】[0029]
【実施例】使用した処理剤の含有濃度（重量％）示す。 （１）ミルスケール：鉄含有量７４％（２）生石灰：Ｃ
ａＯ含有量９２％（３）蛍石：ＣａＦ2 含有量７０％
（４）粒状の金属Ａｌ：含有量９９％。EXAMPLES The contents (% by weight) of the treating agents used are shown. (1) Mill scale: 74% iron content (2) Quicklime: C
aO content 92% (3) fluorite: CaF 2 content 70%
(4) Granular metal Al: content 99%.
【００３０】（本発明例１）表１に示すように、取鍋に
成分調整した１３５０℃の溶銑２５０ｔを装入後、ＫＲ
式の攪拌下、脱珪剤を添加したところ、スラグ中酸化鉄
濃度 (Ｆｅ換算値)を５％以下まで低減するのに約５分
を要した。ＫＲ式の攪拌下、除滓せずに続けて脱硫剤を
添加後、約１０分で溶銑中硫黄濃度を０. ００５％にま
で低下できた。(Example 1 of the present invention) As shown in Table 1, after charging 250 t of 1350 ° C hot metal whose components were adjusted into a ladle,
When the desiliconizing agent was added under the stirring of the formula, it took about 5 minutes to reduce the iron oxide concentration in slag (in terms of Fe) to 5% or less. After the desulfurizing agent was continuously added without removing the slag under KR stirring, the sulfur concentration in the hot metal could be reduced to 0.005% in about 10 minutes.
【００３１】[0031]
【表１】 [Table 1]
【００３２】（本発明例２）表２に示すように、取鍋に
成分調整した１３５０℃の溶銑２５０ｔを装入後、ＫＲ
式の攪拌下、スケールのみを添加した後に生石灰、蛍石
を連続添加したところ、スラグ中 (Ｆｅ換算値) を５％
以下まで低減するのに約４. ５分を要した。ＫＲ式の攪
拌下、除滓せずに続けて脱硫剤を添加後、約１０分で溶
銑中硫黄濃度を０. ００４％にまで低下できた。(Example 2 of the present invention) As shown in Table 2, after charging 250 t of 1350 ° C hot metal whose components were adjusted into a ladle,
Under the stirring of the formula, when only the scale was added and then quicklime and fluorite were continuously added, the content of slag (in terms of Fe) was 5%.
It took about 4.5 minutes to reduce to below. After the desulfurizing agent was continuously added without removing the slag under KR stirring, the sulfur concentration in the hot metal could be reduced to 0.004% in about 10 minutes.
【００３３】[0033]
【表２】 [Table 2]
【００３４】（本発明例３）表３に示すように、取鍋に
成分調整した１３５０℃の溶銑２５０ｔを装入後、ＫＲ
式の攪拌下、スケールのみを添加した後に生石灰、蛍石
を連続添加して攪拌開始から約３分後に粒状の金属Ａｌ
を約０. ４８ｔ追加したところ、その１分後には酸化鉄
濃度 (Ｆｅ換算値) １. ５％にまで低下でき、溶銑中硫
黄濃度も０．００８％にまで低下できた。ＫＲ式の攪拌
下、除滓せずに続けて脱硫剤を添加後、約１０分で溶銑
中硫黄濃度を０. ００２％にまで低下できた。(Example 3 of the present invention) As shown in Table 3, after charging 250t of 1350 ° C hot metal whose components were adjusted into a ladle,
Under the agitation of the formula, after adding only the scale, lime and fluorite are continuously added, and after about 3 minutes from the start of the agitation, the granular metal Al is added.
Was added about 0.48 t, and one minute later, the iron oxide concentration (in terms of Fe) could be reduced to 1.5%, and the sulfur concentration in the hot metal could be reduced to 0.008%. After the desulfurizing agent was continuously added without removing the slag under KR stirring, the sulfur concentration in the hot metal could be reduced to 0.002% in about 10 minutes.
【００３５】[0035]
【表３】 [Table 3]
【００３６】（本発明例４）表４に示すように、取鍋に
成分調整した１３５０℃の溶銑２５０ｔを装入後、ＫＲ
式の攪拌下、スケールのみを添加した後に生石灰、蛍石
を連続添加して攪拌開始から約３. ５分後に粒状の金属
Ａｌを０. ４８ｔ追加したところ、その１分後には酸化
鉄濃度 (Ｆｅ換算値) を１. ５％にまで低下でき、溶銑
中硫黄濃度も０．００８％にまで低下できた。ＫＲ式の
攪拌下、除滓せずに続けて脱硫剤を添加後、約９分で溶
銑中硫黄濃度を０. ００１％にまで低下できた。(Example 4 of the present invention) As shown in Table 4, after charging 250 t of 1350 ° C hot metal whose components were adjusted into a ladle,
Under the agitation of the formula, quick lime and fluorite were continuously added after adding only the scale, and after about 3.5 minutes from the start of stirring, 0.48 t of granular metal Al was added. One minute later, the iron oxide concentration ( Fe conversion value) could be reduced to 1.5%, and the sulfur concentration in the hot metal could be reduced to 0.008%. After the desulfurizing agent was continuously added without removing the slag under KR stirring, the sulfur concentration in the hot metal could be reduced to 0.001% in about 9 minutes.
【００３７】[0037]
【表４】 [Table 4]
【００３８】（比較例１）表５に示すように、取鍋に成
分調整した１３５０℃の溶銑２５０ｔを装入後、ＫＲ式
の攪拌下、脱珪剤としてマンガン鉱石、生石灰、蛍石を
使用して７分間反応させ、ＫＲ機械方式の攪拌下、除滓
せずに続けて生石灰を添加後、約１０分で溶銑中硫黄濃
度は０. ０１３％になった。ＣａＦ2 を多量に添加して
スラグ中濃度で１３％としても、処理後の溶銑中硫黄濃
度を０. ００６％程度までしか低下できなかった。(Comparative Example 1) As shown in Table 5, 250 t of 1350 ° C. hot metal whose components were adjusted was charged into a ladle, and manganese ore, quicklime, and fluorite were used as a desiliconizing agent under KR stirring. The reaction was continued for 7 minutes, and the lime was continuously added without removing the slag under the stirring of the KR mechanical system. After about 10 minutes, the sulfur concentration in the hot metal became 0.013%. Even if a large amount of CaF 2 was added to make the slag concentration 13%, the sulfur concentration in the hot metal after the treatment could only be reduced to about 0.006%.
【００３９】[0039]
【表５】 [Table 5]
【００４０】[0040]
【発明の効果】本発明により、ＣａＦ2 使用を最小限
（５％未満）に抑えて効率よく脱珪、脱硫（目標溶銑中
硫黄濃度：０．００５％以下）処理をすることができ
る。According to the present invention, it is possible to carry out desiliconization and desulfurization (target sulfur concentration in hot metal: 0.005% or less) efficiently while minimizing the use of CaF 2 (less than 5%).
Claims (2)
の溶銑に、鉄酸化物と、ＣａＯと、ＣａＦ2 を添加し、
スラグ中酸化鉄濃度がＦｅ換算値で５％以下とする脱珪
を主とする第一工程と、その後、攪拌下、ＣａＯとＣａ
Ｆ2 を含む脱硫剤を添加する脱硫を主とする第二工程と
から構成されることを特徴とする溶銑の脱珪・脱硫方
法。1. An iron oxide, CaO and CaF 2 are added to hot metal having a silicon concentration of 0.1% or more in hot metal under stirring.
The first step mainly includes desiliconization in which the iron oxide concentration in the slag is 5% or less in terms of Fe, and then CaO and Ca
A desulfurization / desulfurization method for hot metal comprising a second step mainly including desulfurization in which a desulfurizing agent containing F 2 is added.
とを特徴とする請求項１記載の溶銑の脱珪脱硫方法。2. The method for desiliconizing and desulfurizing hot metal according to claim 1, wherein Al is added prior to the second step.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26163497A JPH11100608A (en) | 1997-09-26 | 1997-09-26 | Method for desiliconizing and desulfurizing molten iron |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26163497A JPH11100608A (en) | 1997-09-26 | 1997-09-26 | Method for desiliconizing and desulfurizing molten iron |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH11100608A true JPH11100608A (en) | 1999-04-13 |
Family
ID=17364629
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26163497A Pending JPH11100608A (en) | 1997-09-26 | 1997-09-26 | Method for desiliconizing and desulfurizing molten iron |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH11100608A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100832698B1 (en) * | 2001-12-20 | 2008-05-28 | 주식회사 포스코 | Desulfurization of the molten steel for tire-cord |
| JP2011256445A (en) * | 2010-06-10 | 2011-12-22 | Kobe Steel Ltd | Method for desulfurizing molten iron |
| JP2014091836A (en) * | 2012-10-31 | 2014-05-19 | Nisshin Steel Co Ltd | Desulfurization processing method of molten iron |
-
1997
- 1997-09-26 JP JP26163497A patent/JPH11100608A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100832698B1 (en) * | 2001-12-20 | 2008-05-28 | 주식회사 포스코 | Desulfurization of the molten steel for tire-cord |
| JP2011256445A (en) * | 2010-06-10 | 2011-12-22 | Kobe Steel Ltd | Method for desulfurizing molten iron |
| JP2014091836A (en) * | 2012-10-31 | 2014-05-19 | Nisshin Steel Co Ltd | Desulfurization processing method of molten iron |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7151494B2 (en) | Method for recycling converter slag | |
| JP4765374B2 (en) | Desulfurization treatment method for chromium-containing hot metal | |
| JP3097474B2 (en) | Hot metal dephosphorization method | |
| JP2007270238A (en) | Method for applying dephosphorize-treatment to molten iron | |
| JPH11100608A (en) | Method for desiliconizing and desulfurizing molten iron | |
| JPH10102119A (en) | Production of sulfur free-cutting steel resulfurized carbon steel | |
| JP2001115205A (en) | Method for dephosphorizing molten iron | |
| JP2002241829A (en) | Desiliconizing method for molten iron | |
| JP3288208B2 (en) | Hot metal dephosphorization method | |
| JP2653301B2 (en) | Reusing method of low P converter slag | |
| JPH07179920A (en) | Production of molten steel | |
| JP2001049320A (en) | Production of iron and steel using high phosphorus ore as raw material | |
| JP3704267B2 (en) | Method for refining molten steel | |
| JP3505791B2 (en) | Dephosphorization and desulfurization of hot metal | |
| JPH09176717A (en) | Method for steelmaking molten iron of blast furnace | |
| JPH111714A (en) | Steelmaking method | |
| JP3218629B2 (en) | Hot metal dephosphorization method | |
| JPH07109507A (en) | Method for pretreating molten iron | |
| JP3684953B2 (en) | Pre-silicidation / phosphorization method of hot metal | |
| JP3704912B2 (en) | Hot metal desiliconization and desulfurization methods | |
| SU956567A1 (en) | Process for treating molten cast iron | |
| JP3531480B2 (en) | Hot metal dephosphorization method | |
| JP2842231B2 (en) | Pretreatment of hot metal by bottom-blown gas stirring | |
| JP3297997B2 (en) | Hot metal removal method | |
| JPS636606B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20020827 |