JP3168437B2 - Vacuum refining method - Google Patents
Vacuum refining methodInfo
- Publication number
- JP3168437B2 JP3168437B2 JP12354692A JP12354692A JP3168437B2 JP 3168437 B2 JP3168437 B2 JP 3168437B2 JP 12354692 A JP12354692 A JP 12354692A JP 12354692 A JP12354692 A JP 12354692A JP 3168437 B2 JP3168437 B2 JP 3168437B2
- Authority
- JP
- Japan
- Prior art keywords
- molten steel
- immersion tube
- dephosphorization
- ladle
- slag
- 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 - Fee Related
Links
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
【０００１】[0001]
【産業上の利用分野】本発明は、転炉・電気炉等の精練
炉で溶製された溶鋼を取鍋内で簡便に脱燐する方法に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for easily dephosphorizing molten steel produced in a refining furnace such as a converter or an electric furnace in a ladle.
【０００２】[0002]
【従来の技術】従来、溶鋼の脱燐に際しては、転炉での
多量石灰の利用や転炉装入前の溶銑段階で石灰あるいは
Ｎａ2 ＣＯ3 を用いた予備処理が行われていたが、多量
の石灰の使用による過脱燐が行なわれ、そのためコスト
面を押し上げている。2. Description of the Related Art Conventionally, in the dephosphorization of molten steel, a large amount of lime is used in a converter and pretreatment using lime or Na 2 CO 3 is performed at a hot metal stage before charging the converter. Excessive dephosphorization is carried out by using a large amount of lime, thereby increasing costs.
【０００３】そのため、製鋼過程での溶鋼の脱燐が試み
られている。例えば、特開昭５８−１１７２０号公報に
は、ＣａＯを主成分とするスラグおよびフラックスにア
ルカリ珪酸塩を添加し、脱燐用スラグまたはフラックス
を生成し、これを溶鋼に添加し撹拌混合することが、ま
た、特開平３−１６２５３１号公報には、Ｎａ2 Ｏ、Ｎ
ａ2 ＣＯ3 、Ｎａ2 ＳｉＯ2 などのフラックスを出鋼直
前の溶鋼に添加して滓化させることが開示されている。[0003] Therefore, dephosphorization of molten steel in a steelmaking process has been attempted. For example, Japanese Patent Application Laid-Open No. 58-11720 discloses a method in which an alkali silicate is added to a slag and a flux mainly composed of CaO to produce a slag or a flux for dephosphorization, and the slag or the flux is added to molten steel and mixed with stirring. However, Japanese Patent Application Laid-Open No. Hei 3-162531 discloses that Na 2 O, N
It is disclosed that a flux such as a 2 CO 3 or Na 2 SiO 2 is added to molten steel just before tapping to form slag.
【０００４】しかしながら、製鋼段階での脱燐は、脱燐
処理後、溶鋼と脱燐スラグとの接触による復燐が発生し
て高レベルに清浄化した鋼は得られない。そのため、脱
燐処理後に、除滓機を用いての積極的排滓を行なうこと
も試みられているが、そのための操業が煩雑になるばか
りではなく、溶鋼温度の低下による高品質のものが得ら
れず、また、歩留りの悪化をもたらしている。[0004] However, in the dephosphorization at the steel making stage, after dephosphorization treatment, rephosphorization occurs due to contact between the molten steel and the dephosphorized slag, so that a highly purified steel cannot be obtained. Therefore, after the dephosphorization treatment, an attempt has been made to carry out aggressive slag removal using a slag remover, but this operation not only complicates the operation but also obtains a high-quality slag due to a decrease in molten steel temperature. It is not possible, and the yield is deteriorated.
【０００５】[0005]
【発明が解決しようとする課題】本発明は、かかる溶鋼
の脱燐処理における問題を解消するもので、脱燐後の溶
鋼の復燐がない取鍋内脱燐方法を提供することを目的と
する。SUMMARY OF THE INVENTION An object of the present invention is to solve the problem in the dephosphorization treatment of molten steel, and an object of the present invention is to provide a method for dephosphorization in a ladle without dephosphorization of molten steel after dephosphorization. I do.
【０００６】[0006]
【課題を解決するための手段】本発明は、取鍋内の溶鋼
に、取鍋内径の３０〜８０％の内径を有する直胴型の浸
漬管を浸漬し、同浸漬管内を減圧して同浸漬管の下端開
口面に対して偏倚した位置から添加した精練フラックス
が浸漬管外に流出しないように、不活性ガスを導入する
と共に、同浸漬管内の溶鋼中に脱燐剤と酸素を導入して
脱燐したのち、酸素導入を停止し、不活性ガスの導入量
を増大して同浸漬管の溶鋼を浸漬管外に回流せしめて脱
燐生成物を浸漬管外の溶鋼表面に浮上せしめることを特
徴とする。According to the present invention, a straight body type immersion pipe having an inner diameter of 30 to 80% of the inner diameter of a ladle is immersed in molten steel in a ladle, and the inside of the immersion pipe is depressurized and immersed. Refining flux added from a position deviated from the lower end opening surface of the immersion tube
After introducing an inert gas and dephosphorizing by introducing a dephosphorizing agent and oxygen into the molten steel in the same immersion pipe , oxygen introduction was stopped, and the It is characterized in that the molten steel in the dip tube is circulated to the outside of the dip tube by increasing the amount so that the dephosphorized product floats on the molten steel surface outside the dip tube.
【０００７】脱燐過程の不活性ガスの吹き込み量を０．
０３〜０．３Ｎｌ／ｍｉｎ／ｔｏｎに調整して槽内に添
加した精錬フラックスの系外流出を防止すると共に、脱
燐処理後の吹き込みガス量を０．６Ｎｌ／ｍｉｎ／ｔｏ
ｎ以上に調整して浸漬管内の脱燐スラグを浸漬管外に排
除する。The blowing amount of the inert gas during the dephosphorization process is set at 0.
The refining flux added to the tank is adjusted to 03 to 0.3 Nl / min / ton to prevent the refining flux from flowing out of the system, and the blown gas amount after the dephosphorization treatment is set to 0.6 Nl / min / ton.
Adjust to n or more to eliminate the dephosphorized slag in the dip tube outside the dip tube.
【０００８】脱燐のための導入酸素は酸素ガス、酸素含
有ガス等のガス体であってもよいし、また、酸素を発生
する固形物として添加してもよい。例えば、酸化鉄等の
酸素供給材と石灰などの脱燐材を同時にインジェクショ
ンランスを介して吹き込んでもよい。The oxygen introduced for dephosphorization may be a gas such as oxygen gas or oxygen-containing gas, or may be added as a solid substance that generates oxygen. For example, an oxygen supply material such as iron oxide and a dephosphorizing material such as lime may be simultaneously blown through an injection lance.
【０００９】脱燐後、添加生石灰を速やかに系外に排出
し、排出済の脱燐スラグと溶鋼との接触を防止し、脱炭
処理、脱ガス処理などの二次精錬処理を同一取鍋内で継
続して行うことができる。After the dephosphorization, the added quicklime is quickly discharged to the outside of the system to prevent contact between the discharged dephosphorized slag and molten steel, and to perform secondary refining such as decarburization and degassing in the same ladle. Can be performed continuously.
【００１０】[0010]
【作用】溶鋼の脱燐を溶鋼を循環させながら比較的狭い
浸漬管中で行なうので反応効率を高めることができ、脱
燐生成物は浸漬管の外側で溶鋼との直接接触を絶った状
態で浮上しているので、処理後の復燐も生じない。The dephosphorization of the molten steel is carried out in a relatively narrow immersion pipe while circulating the molten steel, so that the reaction efficiency can be increased. The dephosphorized product is kept out of direct contact with the molten steel outside the immersion pipe. Since it is floating, there is no rephosphorization after the treatment.
【００１１】[0011]
【実施例】添付図は、本発明の実施例としての処理過程
を示す。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a process according to an embodiment of the present invention.
【００１２】図１に示すように、転炉によって得たＣ＝
０．０４％，Ｓｉ＝０．０１％，Ｓ＝０．００７％組
成、１６２０℃の溶鋼Ｍ１７３トンを内径３０００ｍｍ
φ×高さ３４００ｍｍサイズの取鍋１に収容し、これ
に、１６５０ｍｍ内径の大径直胴型の浸漬管２を溶鋼中
に取鍋内の溶鋼の深さ３０００ｍｍに対して、５００ｍ
ｍの深さＨになるように浸漬した。浸漬管２の内部を吸
気して２００トールに減圧し、浸漬管の底部開口の一方
内側の偏心距離αが５００ｍｍになるように、取鍋底部
の吹込み口３から０．３Ｎｌ／ｍｉｎ／ｔｏｎのＡｒガ
スを導入した。そして、浸漬管２から溶鋼トン当たり
２．８ｋｇの生石灰を浸漬管内の溶鋼表面に添加すると
共に、浸漬管２の上方から挿入したランス４から、５．
８Ｎｌ／ｍｉｎ／ｔｏｎのＯ2 ガスを１０分間、吹付け
て脱燐反応を起こした。その後、酸素吹錬を中止し、底
部からのＡｒガスの吹込み量を０．６Ｎｌ／ｍｉｎ／ｔ
ｏｎ以上に上げた。これによって、浸漬管２の内部に泡
立ちを生じ、浸漬管２の一側に盛り上がりＡを形成し、
ガス導入側の反対側から浸漬管２の外側に出る溶鋼の循
環流Ｂを形成した。この循環流Ｂによって、脱燐による
生成物は、未反応の生石灰と共に溶鋼内に混在し、溶鋼
と共に浸漬管２の外に出る。その外部で、脱燐生成物５
と未反応の生石灰６は溶鋼Ｍ中を上昇し、溶鋼表面に浮
上する。そして、比重の関係で、脱燐生成物５の層が未
反応の生石灰６の上に形成され、脱燐生成物５は生石灰
６層によって溶鋼Ｍと遮断され、溶鋼は復燐することは
ない。ここでさらに、浸漬管２から生石灰などの塩基性
フラックスを浸漬管内の溶鋼表面に添加し、底吹からの
Ａｒガス吹込量を０．６Ｎｌ／ｍｉｎ／ｔｏｎ以上で処
理し、未反応フラックスを浸漬管外に流出しさせ、溶鋼
Ｍ中を上昇、溶鋼表面に浮上させ、脱燐スラグと溶鋼と
を完全に分離する作業を行ってもよい。As shown in FIG. 1, C =
0.04%, Si = 0.01%, S = 0.007% composition, M173 tons of molten steel at 1620 ° C. with an inner diameter of 3000 mm
It is stored in a ladle 1 having a size of φ × 3400 mm in height, and a large-diameter straight-body-type immersion pipe 2 having an inner diameter of 1650 mm is placed in the molten steel at a depth of 500 mm for a depth of 3000 mm of the molten steel in the ladle.
It was immersed to a depth H of m. The inside of the dip tube 2 is suctioned to reduce the pressure to 200 Torr, and 0.3 Nl / min / ton is applied from the inlet 3 at the bottom of the ladle so that the eccentric distance α inside one of the bottom openings of the dip tube is 500 mm. Of Ar gas was introduced. Then, 2.8 kg of quicklime per ton of molten steel is added from the immersion pipe 2 to the surface of the molten steel in the immersion pipe 2.
8 Nl / min / ton O 2 gas was sprayed for 10 minutes to cause a dephosphorization reaction. Thereafter, the oxygen blowing was stopped, and the blowing amount of Ar gas from the bottom was reduced to 0.6 Nl / min / t.
raised to more than on. As a result, bubbling is generated inside the immersion tube 2, and a swelling A is formed on one side of the immersion tube 2,
A circulating flow B of molten steel exiting the immersion tube 2 from the side opposite to the gas introduction side was formed. By this circulation flow B, the product of the dephosphorization is mixed in the molten steel together with unreacted quicklime and exits out of the immersion pipe 2 together with the molten steel. Outside that, the dephosphorized product 5
The unreacted quicklime 6 rises in the molten steel M and floats on the molten steel surface. Then, due to the specific gravity, a layer of the dephosphorized product 5 is formed on the unreacted quicklime 6, the dephosphorized product 5 is blocked from the molten steel M by the quicklime 6 layer, and the molten steel does not rephosphorize. . Here, a basic flux such as quick lime is further added to the molten steel surface in the immersion tube from the immersion tube 2, and the Ar gas blowing amount from the bottom blow is treated at 0.6 Nl / min / ton or more to immerse the unreacted flux. An operation of flowing out of the pipe, ascending in the molten steel M, floating on the surface of the molten steel, and completely separating the dephosphorized slag and the molten steel may be performed.
【００１３】さらに、取鍋内溶鋼Ｍ上に浮上する脱燐生
成物５と生石灰６の層は、吸引除去されて、同一装置を
用いて脱炭処理、脱ガス処理などの二次精錬処理を連続
して行なった。Further, the layers of the dephosphorized product 5 and the quicklime 6 floating on the molten steel M in the ladle are removed by suction, and subjected to secondary refining treatment such as decarburization treatment and degassing treatment using the same apparatus. Performed continuously.
【００１４】この二次精錬処理前の溶鋼の組成はＣ＝
０．０４％，Ｐ＝０．０２４％，Ｓ＝０．００７％であ
って、脱燐率は２１％であった。The composition of the molten steel before the secondary refining treatment is C =
0.04%, P = 0.024%, S = 0.007%, and the dephosphorization rate was 21%.
【００１５】[0015]
【発明の効果】本発明によって以下を効果を奏する。According to the present invention, the following effects can be obtained.
【００１６】（１）本発明によって、脱燐スラグと溶鋼
は生石灰により完全に分離され、復燐を防止しているの
で、脱炭、脱ガス、介在物除去、脱硫等の次の二次精錬
を同一の装置を利用しての処理が可能であり、高級鋼の
製造工程を短縮化できる。(1) According to the present invention, the dephosphorized slag and the molten steel are completely separated by quick lime to prevent rephosphorization, so that the following secondary refining such as decarburization, degassing, inclusion removal, desulfurization, etc. Can be processed using the same apparatus, and the manufacturing process of high-grade steel can be shortened.
【００１７】（２）同一精錬炉でのスラグ除去なし操業
で温度降下が抑制され、取鍋内スラグによる保温効果が
あり保温材が減少する。(2) The temperature drop is suppressed by the operation without slag removal in the same refining furnace, and the slag in the ladle has a heat retaining effect, and the heat retaining material is reduced.
【００１８】（３）脱燐スラグと溶鋼との接触を抑制す
ることにより簡便に取鍋内脱燐が可能となる。(3) Dephosphorization in the ladle can be easily performed by suppressing the contact between the dephosphorized slag and the molten steel.
【００１９】（４）スラグ排出などの操業での溶鋼温度
の低下、処理時間の増加などの弊害を回避できる。(4) It is possible to avoid adverse effects such as a decrease in molten steel temperature in operation such as slag discharge and an increase in processing time.
【００２０】（５）脱燐スラグと溶鋼との接触を抑制す
ることにより簡便に取鍋内脱燐が可能となる。(5) Dephosphorization in the ladle can be easily performed by suppressing the contact between the dephosphorized slag and the molten steel.
【００２１】（６）脱燐スラグと溶鋼との接触を絶って
復燐を防止できる。(6) Contact between the dephosphorized slag and the molten steel can be cut off to prevent rephosphorization.
【００２２】（７）取鍋内の溶鋼脱燐が容易にできる。(7) Dephosphorization of molten steel in the ladle can be easily performed.
【００２３】（８）脱燐過程での脱燐スラグの除去をす
ることなく、温度降下を抑制する効果がある。(8) There is an effect of suppressing the temperature drop without removing the dephosphorized slag in the dephosphorizing process.
【図１】 本発明の実施態様を示す。FIG. 1 illustrates an embodiment of the present invention.
１ 取鍋 ２ 浸漬管 ３ 不活性ガス吹込口 ４ 酸素吹製ランス ５ 生石灰 ６ 脱燐スラグ Reference Signs List 1 ladle 2 dip tube 3 inert gas injection port 4 oxygen blowing lance 5 quicklime 6 dephosphorized slag
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平１−92314（ＪＰ，Ａ) 特開 昭58−11720（ＪＰ，Ａ) 特開 昭52−150305（ＪＰ，Ａ) 特開 平２−93015（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C21C 7/10 C21C 7/064 C21C 7/076 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-92314 (JP, A) JP-A-58-11720 (JP, A) JP-A-52-150305 (JP, A) JP-A-2- 93015 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) C21C 7/10 C21C 7/064 C21C 7/076
Claims (1)
％の内径を有する直胴型の浸漬管を浸漬し、同浸漬管内
を減圧して同浸漬管の下端開口面に対して偏倚した位置
から添加した精練フラックスが浸漬管外に流出しないよ
うに、不活性ガスを導入すると共に同浸漬管内の溶鋼中
に脱燐剤と酸素を導入して脱燐したのち、酸素導入を停
止し、不活性ガスの導入量を増大して同浸漬管の溶鋼を
浸漬管外に回流せしめて脱燐生成物を浸漬管外の溶鋼表
面に浮上せしめる真空精練方法。(1) The molten steel in the ladle has a ladle inner diameter of 30 to 80 mm.
% Of the inside of the immersion tube, and the pressure inside the immersion tube is reduced to prevent the scouring flux added from the position deviated from the lower end opening surface of the immersion tube from flowing out of the immersion tube .
Thus, after introducing an inert gas and dephosphorizing by introducing a dephosphorizing agent and oxygen into the molten steel in the same immersion tube, oxygen introduction was stopped, and the amount of the inert gas introduced was increased. A vacuum scouring method in which the molten steel in the immersion tube is circulated outside the immersion tube so that the dephosphorized product floats on the surface of the molten steel outside the immersion tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12354692A JP3168437B2 (en) | 1992-05-15 | 1992-05-15 | Vacuum refining method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12354692A JP3168437B2 (en) | 1992-05-15 | 1992-05-15 | Vacuum refining method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05320739A JPH05320739A (en) | 1993-12-03 |
| JP3168437B2 true JP3168437B2 (en) | 2001-05-21 |
Family
ID=14863278
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12354692A Expired - Fee Related JP3168437B2 (en) | 1992-05-15 | 1992-05-15 | Vacuum refining method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3168437B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2340690C (en) * | 1999-06-16 | 2005-03-15 | Nippon Steel Corporation | Method for refining molten steel and apparatus therefor |
| KR101490187B1 (en) * | 2013-07-04 | 2015-02-05 | 주식회사 포스코 | Method of refining molten steel |
-
1992
- 1992-05-15 JP JP12354692A patent/JP3168437B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05320739A (en) | 1993-12-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3176374B2 (en) | Method for producing low carbon molten steel by vacuum degassing decarburization | |
| JP3168437B2 (en) | Vacuum refining method | |
| JPH11279630A (en) | Method for smelting highly cleaned steel | |
| JPH05239534A (en) | Method for melting non-oriented electric steel sheet | |
| JP3786056B2 (en) | Hot metal pretreatment method | |
| JP2767674B2 (en) | Refining method of high purity stainless steel | |
| JPH0987732A (en) | Method for refining molten steel | |
| JPH0153329B2 (en) | ||
| JP2880842B2 (en) | How to make clean steel | |
| JP3370349B2 (en) | Melting method of high cleanness ultra low carbon steel | |
| JPH0734113A (en) | Converter refining method | |
| JP3127733B2 (en) | Manufacturing method of ultra clean ultra low carbon steel | |
| JPH1150122A (en) | Dephosphorize-refining of molten iron in converter type refining vessel | |
| JPH01156416A (en) | Method for decarburizing high-chromium steel having excellent decarburizing characteristic under reduced pressure | |
| KR100926321B1 (en) | Metallurgical treatment method on a metal bath | |
| JP3769779B2 (en) | Method for melting ultra-low carbon Cr-containing steel | |
| JP3736068B2 (en) | Hot metal pretreatment method | |
| JPH0480316A (en) | Method for decarburizing molten steel under reduced pressure | |
| JP3071445B2 (en) | Methods for reducing nitrogen in vacuum refining of molten steel. | |
| JP3290794B2 (en) | Molten steel refining method under reduced pressure | |
| JP3823733B2 (en) | Hot metal dephosphorization method | |
| JPH04318119A (en) | Production of high clean steel | |
| JPS6214001B2 (en) | ||
| JPS58181817A (en) | Manufacture of low-phosphorus al-killed steel | |
| JPH11241117A (en) | Method for melting highly clean and extra-low carbon steel |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20010119 |
|
| LAPS | Cancellation because of no payment of annual fees |