JPH0420963B2 - - Google Patents
Info
- Publication number
- JPH0420963B2 JPH0420963B2 JP24311284A JP24311284A JPH0420963B2 JP H0420963 B2 JPH0420963 B2 JP H0420963B2 JP 24311284 A JP24311284 A JP 24311284A JP 24311284 A JP24311284 A JP 24311284A JP H0420963 B2 JPH0420963 B2 JP H0420963B2
- Authority
- JP
- Japan
- Prior art keywords
- hot metal
- gutter
- pressure
- closed space
- pressurized
- 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
Links
- 239000002184 metal Substances 0.000 claims description 52
- 229910052751 metal Inorganic materials 0.000 claims description 51
- 238000000034 method Methods 0.000 claims description 11
- 239000003795 chemical substances by application Substances 0.000 claims description 10
- 238000002485 combustion reaction Methods 0.000 claims description 3
- 230000001590 oxidative effect Effects 0.000 claims description 2
- 238000011144 upstream manufacturing Methods 0.000 claims description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 15
- 239000002893 slag Substances 0.000 description 9
- 235000013980 iron oxide Nutrition 0.000 description 6
- 238000003756 stirring Methods 0.000 description 4
- 238000003860 storage Methods 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 210000001015 abdomen Anatomy 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 244000005894 Albizia lebbeck Species 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000005262 decarbonization Methods 0.000 description 1
- 239000002274 desiccant Substances 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- VBMVTYDPPZVILR-UHFFFAOYSA-N iron(2+);oxygen(2-) Chemical class [O-2].[Fe+2] VBMVTYDPPZVILR-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C1/00—Refining of pig-iron; Cast iron
- C21C1/04—Removing impurities other than carbon, phosphorus or sulfur
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0081—Treating and handling under pressure
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Description
（産業上の利用分野）
本発明は、溶銑中のSiを加圧下において酸化除
去し、低Si含有溶銑を製造する方法に関するもの
である。
（従来の技術）
近年の高級鋼の需要増大に伴ない、転炉に使用
する溶銑の脱Ｐ、脱Ｓ処理の量が増大している。
ところで、溶銑の脱Ｐ、脱Ｓ処理は、トーピード
カーあるいは取鍋に溶銑を受銑してCaO等の脱
Ｐ、脱Ｓ剤を添加することにより行つているが、
この場合溶銑中のSiの含有率が高い場合にはSiが
優先的に酸化されてSiO2を生成するために発生
スラグ量の増大と添加剤の無駄な消費を招くこと
になり、従つて予め溶銑中のSiを低下させておく
必要がある。
そして、Si含有率を低下させる手段は、脱Ｐ、
脱Ｓ処理前に焼結鉱等の酸化鉄を溶銑中に添加し
て下記式に示すような脱Si処理を行うものであ
る。
Ｓｉ＋2FeO＝（SiO2）＋2Fe ……
なお、前記式において、元素名の下にひいた
線はその成分が溶銑中に存在するものであること
を示し、また（ ）はその化合物がスラグ中に存
在するものであることを示す慣用表記法である。
また、酸化鉄はFeOで代表して示しているが、異
なる組成の酸化鉄の場合も同様である。
しかしながら、脱si処理工程では下記式に示
す反応により溶銑中のＣと酸化鉄の直接還元反応
を併発する。
Ｃ＋FeO＝CO（ｇ）＋Fe ……
なお、前記式において（ｇ）は化合物が気体
であることを示す慣用表記法である。つまり、
式に示すような直接還元反応が生ずると、酸化鉄
が脱Si反応に関与しなくなるばかりでなく、CO
（ｇ）の発生によりスラグフオーミングを生じて
作業の非能率化をもたらすことにもなる。
そこで、前記したような問題を解決する方法と
して、溶銑表面雰囲気を加圧する方法が特公昭57
−17044号で開示されている。すなわち、この方
法は、1.1気圧以上に加圧された状況下において
酸素源を添加し、脱Ｃを極力抑制しつつ低Si溶銑
を得るものである。
（発明が解決しようとする問題点）
しかし、先に述べた特公昭57−17044号による
方法は、取鍋にて脱Si処理を行ない、加圧雰囲気
の形成手段として加圧調整装置による外気圧の加
圧あるいは溶銑表面から150mm以上の深さの点に
脱si剤を直接供給して溶銑の静圧による加圧を用
いていること、および溶銑撹拌用にインペラーあ
るいは不活性ガス導入装置を用いること、等から
作業の煩雑化と付帯装置の複雑化をもたらすとい
う問題があつた。
（問題点を解決するための手段）
本発明は上記問題点を解決せんとして成された
ものであり、その要旨は、出銑樋途中に密閉空間
を形成し、この密閉空間を高炉炉内圧を用いて加
圧雰囲気と成さしめること、および、前記加圧雰
囲気と成さしめた出銑樋途中の密閉空間内にある
溶銑あるいはその上流の溶銑中に脱Si剤を投入す
ることである。
すなわち、このようにすることで、別個の加圧
装置や、撹拌装置を必要とすることなく、溶銑中
のＣの燃焼を可及的に防止しながら溶銑中のSiを
効率よく酸化除去できるものである。
なお、前記脱Si剤としては、焼結鉱やミルスケ
ール等の酸化鉄、あるいは気体酸素等が採用され
る。
（実施例）
以下本発明を添付図面に基づいて説明する。
図中、１は高炉、２は出銑口、３は前記出銑口
２より大樋４に出銑された溶銑、５は前記大樋４
を流れる溶銑３中にその下部を浸漬されたスキン
マー、６は前記スキンマー５により溶銑３と分離
されたスラグを排出するスラグ排出口である。
７は前記スキンマー５によつて分離された溶銑
３をトーピードカーや取鍋まで導く溶銑樋であ
り、本実施例ではこの溶銑樋７と大樋４間に密閉
空間８を形成している。
すなわち、前記スキンマー５の下流に堰９を設
け、これらスキンマー５と堰９間すなわち大樋４
と溶銑樋７を接続する脱si樋１０をカバー１１を
用いて密閉し、密閉空間８を形成している。
１２は前記密閉空間８内の溶銑３に投入する脱
Si剤１３の貯蔵ホツパーであり、該貯蔵ホツパー
１２の排出口近傍には図示省略したが排出量制御
弁が設けられ、溶銑３中に投入する脱Si剤１３量
を適正に制御している。
１４は高炉１の例えば炉腹部と前記密閉空間８
とを接続する配管１５途中に設けられた圧力調整
装置であり、これにより密閉空間８内は適正な加
圧雰囲気に保たれる。
なお、前記密閉空間８内を加圧状態と成さしめ
る高炉炉内圧は、炉腹部の圧力に限らず、炉頂圧
あるいは送風圧等を用いてもよい。また、前記大
樋４ならびに溶銑樋７と脱Si樋１０との溶銑３表
面の高度差ｈ（mm）は、溶銑表面の圧力差Ｐ
（atm）と溶銑密度ρ（ｇ／cm3）を用いて下記式
の如くあらわされるため、高度差ｈに応じた脱Si
樋１０の設計を行えばよい。
ｈ＝10332・Ｐ／ρ ……
すなわち、溶銑３は高炉１の出銑口２から排出
され、本樋４に設けたスキンマー５にてスラグと
分離され脱Si樋１０に流入する。そして溶銑３表
面がスキンマー５を通つて堰９の下端に達した時
点、すなわち、脱Si樋１０とカバー１１およびス
キンマー５と堰９で囲われた部分が密閉状態とな
つた時点で圧力調整装置１４を作動させて該密閉
空間８内の溶銑３表面を加圧する。加圧が完了す
ると、この溶銑３に対して、脱Si樋１０あるいは
大樋４の適当位置において脱Si剤１３を投入す
る。これにより溶銑３の流れによる自然な撹拌が
利用できてスラグフオーミングを加圧によつて最
小限に抑制しながら溶銑３中のSiの安定した酸化
処理操業が行えるのである。
（具体例）
次に本発明方法を用いて溶銑を加圧脱Siした結
果を示す。なお、使用した脱si剤の性状は下記第
１表の如くである。
(Industrial Application Field) The present invention relates to a method for producing low-Si content hot metal by oxidizing and removing Si in hot metal under pressure. (Prior Art) With the increase in demand for high-grade steel in recent years, the amount of deP and sulfur treatment for hot metal used in converters has increased.
By the way, the deP and S removal treatment of hot metal is carried out by receiving the hot metal in a torpedo car or ladle and adding a deP and deS agent such as CaO.
In this case, if the content of Si in the hot metal is high, Si will be preferentially oxidized to produce SiO 2 , leading to an increase in the amount of slag generated and wasteful consumption of additives. It is necessary to reduce the Si content in hot metal. The means to reduce the Si content include dephosphorization,
Before the S removal treatment, iron oxide such as sintered ore is added to the hot metal to perform the Si removal treatment as shown in the following formula. Si + 2FeO = (SiO 2 ) + 2Fe ... In the above formula, the line drawn under the element name indicates that the component exists in the hot metal, and the parentheses indicate that the compound exists in the slag. This is a common notation to indicate that something exists in .
Furthermore, although FeO is shown as a representative iron oxide, the same applies to iron oxides with different compositions. However, in the desiliconization process, a direct reduction reaction between C in the hot metal and iron oxide occurs simultaneously through the reaction shown in the following formula. C +FeO=CO(g)+Fe... In the above formula, (g) is a common notation indicating that the compound is a gas. In other words,
When a direct reduction reaction as shown in the equation occurs, not only does iron oxide not participate in the Si removal reaction, but also CO
The occurrence of (g) also causes slag forming, resulting in inefficiency of work. Therefore, as a method to solve the above-mentioned problems, a method of pressurizing the surface atmosphere of hot metal was proposed in the Tokoku Koko 57.
-Disclosed in No. 17044. That is, in this method, an oxygen source is added under a pressurized condition of 1.1 atmospheres or more, and low-Si hot metal is obtained while suppressing decarbonization as much as possible. (Problems to be Solved by the Invention) However, in the method disclosed in Japanese Patent Publication No. 57-17044 mentioned above, the Si removal treatment is performed in a ladle, and the external pressure is or by directly supplying a desilicon agent to a depth of 150 mm or more from the surface of the hot metal, using static pressure of the hot metal, and using an impeller or an inert gas introduction device to stir the hot metal. This has led to problems such as complicating the work and complicating the auxiliary equipment. (Means for Solving the Problems) The present invention has been made to solve the above problems, and its gist is to form a closed space in the middle of the tap trough, and to use this closed space to reduce the internal pressure of the blast furnace. A desiliconizing agent is injected into the hot metal in a closed space in the middle of the tapping flue that has created the pressurized atmosphere or into the hot metal upstream thereof. In other words, by doing this, Si in the hot metal can be efficiently oxidized and removed while preventing the combustion of C in the hot metal as much as possible without requiring a separate pressurizing device or stirring device. It is. Note that as the desiliconizing agent, iron oxide such as sintered ore or mill scale, gaseous oxygen, or the like is used. (Example) The present invention will be described below based on the accompanying drawings. In the figure, 1 is the blast furnace, 2 is the tap hole, 3 is the hot metal tapped from the tap hole 2 into the large sluice 4, and 5 is the large sluice 4.
A skinmer 6 whose lower part is immersed in the hot metal 3 flowing through the skin is a slag discharge port for discharging the slag separated from the hot metal 3 by the skinmer 5. Reference numeral 7 denotes a hot metal trough that guides the hot metal 3 separated by the skimmer 5 to the torpedo car or ladle, and in this embodiment, a closed space 8 is formed between the hot metal trough 7 and the large gutter 4. That is, a weir 9 is provided downstream of the skimmer 5, and the gap between the skinmer 5 and the weir 9, that is, the large gutter 4
A desilicon gutter 10 connecting the hot metal gutter 7 to the hot metal gutter 7 is hermetically sealed using a cover 11 to form a sealed space 8. Reference numeral 12 denotes a dehydrator to be introduced into the hot metal 3 in the closed space 8.
This is a storage hopper for the Si agent 13, and a discharge amount control valve (not shown) is provided near the discharge port of the storage hopper 12 to properly control the amount of the Si desilicon agent 13 introduced into the hot metal 3. Reference numeral 14 denotes, for example, the furnace belly portion of the blast furnace 1 and the sealed space 8.
This is a pressure regulating device provided in the middle of the pipe 15 connecting the two, and thereby the inside of the closed space 8 is maintained at an appropriately pressurized atmosphere. Note that the internal pressure of the blast furnace which makes the inside of the closed space 8 pressurized is not limited to the pressure of the furnace abdomen, but may be the furnace top pressure, the blowing pressure, or the like. In addition, the height difference h (mm) of the surface of the hot metal 3 between the large gutter 4, the hot metal gutter 7, and the Si-free gutter 10 is the pressure difference P on the surface of the hot metal.
(atm) and the hot metal density ρ (g/cm 3 ) as shown in the following formula, so the amount of Si removed depending on the altitude difference h is
What is necessary is to design the gutter 10. h=10332·P/ρ... That is, the hot metal 3 is discharged from the tap hole 2 of the blast furnace 1, separated from slag by the skimmer 5 provided in the main gutter 4, and flows into the deSi-removal gutter 10. Then, when the surface of the hot metal 3 passes through the skinmer 5 and reaches the lower end of the weir 9, that is, when the area surrounded by the desilicon gutter 10, the cover 11, the skinmer 5, and the weir 9 is in a sealed state, the pressure adjustment device 14 is operated to pressurize the surface of the hot metal 3 in the closed space 8. When pressurization is completed, a desiliconizing agent 13 is introduced into the hot metal 3 at an appropriate position in the desiliconizing gutter 10 or the large gutter 4. This makes it possible to utilize the natural agitation caused by the flow of the hot metal 3 and to perform a stable oxidation treatment operation for Si in the hot metal 3 while suppressing slag forming to a minimum through pressurization. (Specific Example) Next, the results of pressurized Si removal of hot metal using the method of the present invention will be shown. The properties of the desiccant agent used are as shown in Table 1 below.
【表】【table】
【表】【table】
【表】
本具体例より本発明方法によれば、溶銑中のＣ
の燃焼を0.05〜0.1％程度に抑えることができて
CO（ｇ）の発生量を抑制できると共に、加圧下に
あるため発生ガス体積が小さくなることにより脱
Si処理中のスラグフオーミングを防止することが
できることが確認できた。
（発明の効果）
以上述べた如く本発明方法は、高炉炉内圧を用
いて溶銑を加圧すると共に、溶銑の流れによる自
然な撹拌を利用して溶銑を加圧脱Siする為、別個
に加圧装置や撹拌装置を必要とせず、かつ、短い
処理時間でしかも溶銑温度の低下を最小限に抑え
て脱Si処理が行え、脱Ｐ、脱Ｓ処理前に行う脱Si
処理プロセスとして極めて有益なるものである。[Table] From this specific example, according to the method of the present invention, C in hot metal
combustion can be suppressed to around 0.05 to 0.1%.
In addition to suppressing the amount of CO (g) generated, the volume of gas generated is smaller due to the pressure
It was confirmed that slag forming during Si processing can be prevented. (Effects of the Invention) As described above, the method of the present invention uses the internal pressure of the blast furnace to pressurize the hot metal, and also pressurizes the hot metal to remove Si by using the natural stirring of the hot metal flow. It is possible to perform Si removal treatment without the need for equipment or stirring equipment, in a short processing time, and while minimizing the drop in hot metal temperature.
This is extremely useful as a treatment process.
図面は本発明方法の実施の一態様を示す説明図
である。
１は高炉、２は出銑口、３は溶銑、４は大樋、
５はスキンマー、６はスラグ排出口、７は溶銑
樋、８は密閉空間、９は堰、１０は脱Si樋、１１
はカバー、１２は貯蔵ホツパー、１３は脱Si剤、
１４は圧力調整装置、１５は配管。
The drawings are explanatory views showing one embodiment of the method of the present invention. 1 is the blast furnace, 2 is the taphole, 3 is the hot metal, 4 is the gutter,
5 is a skimmer, 6 is a slag discharge port, 7 is a hot metal gutter, 8 is a closed space, 9 is a weir, 10 is a Si removal gutter, 11
is a cover, 12 is a storage hopper, 13 is a desiliconizing agent,
14 is a pressure regulator, and 15 is piping.
Claims (1)
閉空間を加圧雰囲気と成さしめ、この加圧雰囲気
中の溶銑あるいはその上流の溶銑中に脱Si剤を投
入し溶銑中のＣの燃焼を防止しながら溶銑中のSi
を酸化除去することを特徴とする溶銑の加圧脱珪
方法。1. Using the internal pressure of the blast furnace, a closed space formed in the tap hole is made into a pressurized atmosphere, and a desiliconizing agent is introduced into the hot metal in this pressurized atmosphere or into the hot metal upstream of it to remove C from the hot metal. Si in hot metal while preventing combustion
A method for pressurized desiliconization of hot metal, which is characterized by oxidizing and removing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24311284A JPS61124512A (en) | 1984-11-16 | 1984-11-16 | Method for desiliconizing molten pig iron under pressure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24311284A JPS61124512A (en) | 1984-11-16 | 1984-11-16 | Method for desiliconizing molten pig iron under pressure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61124512A JPS61124512A (en) | 1986-06-12 |
| JPH0420963B2 true JPH0420963B2 (en) | 1992-04-07 |
Family
ID=17098972
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24311284A Granted JPS61124512A (en) | 1984-11-16 | 1984-11-16 | Method for desiliconizing molten pig iron under pressure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61124512A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020022577A1 (en) * | 2018-07-24 | 2020-01-30 | 주식회사 포스코 | Apparatus for molten iron runner desilication |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5439208B2 (en) * | 2010-01-28 | 2014-03-12 | 株式会社神戸製鋼所 | Desiliconization method of hot metal in blast furnace casting |
-
1984
- 1984-11-16 JP JP24311284A patent/JPS61124512A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020022577A1 (en) * | 2018-07-24 | 2020-01-30 | 주식회사 포스코 | Apparatus for molten iron runner desilication |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61124512A (en) | 1986-06-12 |
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