JP2000345230A - Operation method of electric furnace - Google Patents
Operation method of electric furnaceInfo
- Publication number
- JP2000345230A JP2000345230A JP15671699A JP15671699A JP2000345230A JP 2000345230 A JP2000345230 A JP 2000345230A JP 15671699 A JP15671699 A JP 15671699A JP 15671699 A JP15671699 A JP 15671699A JP 2000345230 A JP2000345230 A JP 2000345230A
- Authority
- JP
- Japan
- Prior art keywords
- furnace
- melting
- tapping
- scrap
- electric furnace
- 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
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
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
Abstract
(57)【要約】
【課題】 スクラップの溶解に使用する偏芯炉底出鋼方
式の電気炉においては炉体形状の影響で、出鋼口側の炉
壁下部にスクラップの溶解遅れが発生していた。本発明
は、この溶解遅れ解消し、溶解電力原単位ならびに生産
性を改善する偏芯炉底出鋼方式の電気炉を提供する。
【解決手段】 出鋼口上部の水冷ジャケットあるいは炉
殻に設置した中細ノズルを用い酸素ガスを吹きこむこと
により、出鋼口側の溶解を促進させ、電気炉内の溶解速
度の均一化を図ることによって溶解電力原単位ならびに
生産性を改善する。
(57) [Summary] [PROBLEMS] In an eccentric furnace bottom tapping type electric furnace used for melting scrap, the melting of scrap occurs at the bottom of the furnace wall on the tapping port side due to the influence of the furnace body shape. I was The present invention provides an eccentric furnace bottom tapping-type electric furnace that eliminates this melting delay and improves the melting power unit consumption and productivity. SOLUTION: By blowing oxygen gas using a water cooling jacket above the tap hole or a medium-thin nozzle installed in the furnace shell, melting on the tap hole side is promoted, and the melting rate in the electric furnace is made uniform. By doing so, the dissolution power consumption unit and productivity are improved.
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、スクラップ等の金
属材料の溶解、精錬等に使用される偏心炉底出鋼方式の
電気炉における操業方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating an electric furnace of an eccentric furnace bottom tapping type used for melting and refining metal materials such as scrap.
【０００２】[0002]
【従来の技術】スクラップ等の金属材料の溶解、溶融金
属の精錬等に使用される電気炉は、主に電気エネルギー
を使用しているが、溶解を促進させるため補助エネルギ
ーを使用することが一般的となりつつある。補助エネル
ギーを使用する方法としては可燃性ガス、重油、灯油な
どの燃料を燃焼することができる助燃バーナーを炉壁に
設置して使用する方法や、作業口からスクラップや炉内
の溶鋼に向かって酸素ガスおよび炭素粉等を吹き込む方
法がある。2. Description of the Related Art Electric furnaces used for melting metal materials such as scraps and refining molten metal mainly use electric energy, but generally use auxiliary energy to promote melting. It is becoming a target. As a method of using auxiliary energy, there is a method of installing an auxiliary burner on the furnace wall that can burn fuel such as flammable gas, heavy oil, kerosene, etc., or from the working port to scrap or molten steel in the furnace. There is a method of blowing oxygen gas and carbon powder.
【０００３】この方法の一例として特開平８−７５３６
４号公報には、炉壁に先端をコールドスポットに向けた
可燃性ガスを使用した助燃バーナーを設け、このバーナ
ー中心部に酸素ガスの吐出管を設けるとともに、この吐
出管の先端部をスロートを有する中細ノズルとなし、高
速酸素を吐出すことによってスクラップの溶解促進を狙
った技術が提案されている。An example of this method is disclosed in Japanese Patent Application Laid-Open No. H8-7536.
In Japanese Patent Publication No. 4 (1999) -1994, a burner using a combustible gas with a tip directed to a cold spot is provided on a furnace wall, and a discharge pipe for oxygen gas is provided at the center of the burner, and a throat is provided at the tip of the discharge pipe. There has been proposed a technology which aims at promoting the dissolution of scrap by discharging high-speed oxygen by using a medium-sized nozzle having the same.
【０００４】しかし、当該技術では溶解に要する電力原
単位や溶解作業時間の改善はできるものの、酸素ガスに
よるスクラップの溶断中に発生する溶融飛沫の跳ね返り
によってバーナーが詰まり、継続的に効果を発揮するこ
とができないという問題や、バーナー直前に落下してき
た予熱不足の低温のスクラップに跳ね返された火炎や酸
素ガスによって、バーナーの先端、およびその周辺の構
造物を溶損させるという問題があった。[0004] However, although the power consumption required for melting and the melting operation time can be improved by this technique, the burner is clogged by the rebound of molten droplets generated during the melting of the scrap by oxygen gas, and the effect is continuously exerted. There is a problem that the burner cannot be used, and a problem that the tip of the burner and its surrounding structures are melted and damaged by the flame or oxygen gas rebounded by the low-temperature scrap with insufficient preheating that has fallen immediately before the burner.
【０００５】この問題点を解決するために特開平１０−
２６７５４１号公報には、バーナーの上側となる壁位置
にスクラップの跳ね返し部を設け、スクラップを跳ね返
してバーナーから遠ざけ、バーナーの先端、およびその
周辺の構造物の溶損を防止するという技術が提案されて
いる。しかし、当該技術および前記特開平８−７５３６
４号公報の技術においては、バーナーを炉壁に設置して
おり、装入されているスクラップの溶断、溶解が限定さ
れ、偏心炉底出鋼方式の電気炉における出鋼口側近傍の
スクラップの溶解促進を図るのは難しい。To solve this problem, Japanese Patent Laid-Open No.
Japanese Patent No. 267541 proposes a technique in which a scrap rebound portion is provided at a wall position on the upper side of the burner, the scrap is rebounded, and the scrap is repelled away from the burner to prevent the tip of the burner and the surrounding structures from being melted. ing. However, the technique and the Japanese Patent Application Laid-Open No.
In the technology disclosed in Japanese Patent Publication No. 4 (1994), a burner is installed on the furnace wall, and the melting and melting of the loaded scrap is limited, and the scrap near the tapping port side in the eccentric hearth tapping type electric furnace is limited. It is difficult to promote dissolution.
【０００６】一方、特開平６−１７４３７５号公報に
は、具体的な記述が無いものの、図１中にあるように、
出鋼口が電気炉の先端下部に取り付けられている偏芯炉
底出鋼方式の電気炉の出鋼口と思われる部分の上部に位
置する排ガスの排出口の蓋に、当該部位周辺へのスラグ
付着を防止するためにスラグを溶融、切断するための燃
焼バーナーを設置する技術が開示されている。しかしな
がら、当該技術は付着スラグの溶解であり、出鋼口側で
の装入スクラップの溶解遅れについて解決が図れず、操
業効率の向上については依然として問題が残されてい
る。On the other hand, Japanese Patent Application Laid-Open No. 6-174375 has no specific description, but as shown in FIG.
An outlet for exhaust gas, which is located above the part considered to be a tapping hole of an eccentric furnace bottom tapping type electric furnace in which the tapping port is attached to the lower part of the tip of the electric furnace, A technique of installing a combustion burner for melting and cutting slag to prevent slag adhesion is disclosed. However, this technique dissolves the adhered slag and cannot solve the dissolution delay of the charged scrap at the tapping port side, and there is still a problem in improving the operation efficiency.
【０００７】[0007]
【発明が解決しようとする課題】電気炉の操業方法にお
いて、生産性を高めるために種々の高速溶解技術が考案
され適用されてきた結果、溶解に要する時間は大幅に短
縮してきたが、出鋼口側の溶解遅れが更なる改善を図る
上で大きな問題となってきた。SUMMARY OF THE INVENTION In a method of operating an electric furnace, various high-speed melting techniques have been devised and applied in order to increase productivity. As a result, the time required for melting has been greatly reduced. The dissolution delay on the mouth side has been a major problem in achieving further improvements.
【０００８】一般的な電気炉操業では作業口側からアー
ク効率を高めるため、あるいは鋼の精錬をおこなうため
に酸素ガスや炭素粉が溶鋼に向かって吹き込まれてい
る。よって、作業口周辺の溶鋼の撹拌が強化される結
果、その周辺の溶解状況は非常に良好となっているが、
それ以外の部位は溶解が遅れる傾向にあった。その対策
として炉壁の適当な場所に、例えば前記従来技術のよう
にバーナーを設置し溶解促進を図るものの、やはり作業
口周辺に比べると溶解速度は低くかつ不安定であるとい
う問題があった。In general electric furnace operation, oxygen gas or carbon powder is blown toward molten steel in order to increase arc efficiency from the working port side or to refine steel. Therefore, as a result of strengthening the stirring of the molten steel around the working port, the melting state around the working port is very good,
Other sites tended to delay dissolution. As a countermeasure, a burner is installed at an appropriate place on the furnace wall, for example, as in the above-mentioned prior art to promote the melting, but there is a problem that the melting speed is low and unstable compared with the vicinity of the working port.
【０００９】特に近年普及してきている偏芯炉底出鋼方
式の電気炉操業においては、出鋼口上部周辺の空隙が大
きくなっていることと、炉壁に設置したバーナーで火炎
を効果的に当てることが困難であることから、図４に示
すように、出鋼口側の炉壁下部周辺には、溶解速度が極
めて低くかつ不安定であるスクラップの溶解不良領域Ａ
が残る。Particularly in the electric furnace operation of the eccentric furnace bottom tapping method which has become widespread in recent years, the gap around the tap hole is large and the burner installed on the furnace wall effectively suppresses the flame. As shown in FIG. 4, in the vicinity of the lower part of the furnace wall on the tapping side, the melting rate of the scrap is extremely low and unstable, and as shown in FIG.
Remains.
【００１０】それゆえ、生産性を高める、つまり溶解作
業時間を極端に短くしていくと当該部位に未溶解スクラ
ップが残存し、出鋼作業中に出鋼口に未溶解物が詰まる
か、あるいは出鋼中に未溶解スクラップが溶解し溶鋼の
温度が低下し出鋼が中断する等の操業トラブルを引き起
こしたりするようになってきた。またこれらを回避しよ
うとして過剰に溶解エネルギーを使用するという問題も
顕在化してきた。Therefore, if the productivity is increased, that is, if the melting operation time is extremely shortened, unmelted scrap remains in the relevant portion and unmelted material is clogged in the tap hole during the tapping operation, or Unmelted scrap melts during tapping, and the temperature of the molten steel decreases, causing operation troubles such as interruption of tapping. In addition, the problem of excessive use of dissolution energy in order to avoid these has also become apparent.
【００１１】本発明は上記事情に鑑みてなされたもので
あって、スクラップの溶解に使用する偏芯炉底出鋼方式
の電気炉の操業方法において、出鋼口上部壁の水冷ジャ
ケットに設置した中細ノズルを用い所定の期間、酸素ガ
スを吹きこむことにより、ノズル先端やその周辺の構造
物の溶損を発生させること無く出鋼口側の溶解を促進さ
せることができる効率的な電気炉を提供することを目的
とする。The present invention has been made in view of the above circumstances, and in an operation method of an electric furnace of an eccentric furnace bottom tapping method used for melting scrap, the present invention is installed in a water cooling jacket on an upper wall of a tapping outlet. Efficient electric furnace that blows oxygen gas for a predetermined period using a medium-thin nozzle and can promote melting at the tapping port side without causing melting of the nozzle tip and surrounding structures The purpose is to provide.
【００１２】[0012]
【課題を解決するための手段】上記目的を達成するため
本発明は、スクラップの溶解に使用し、出鋼口が電気炉
の先端下部に取り付けられている偏芯炉底出鋼方式の電
気炉の操業方法において、出鋼口上部壁の水冷ジャケッ
トに、水冷式の先端部にスロートを有する中細ノズルを
設置し、該ノズルより、出鋼口近傍の未溶解スクラップ
に向けて酸素ガスを吹きこむことを特徴とする電気炉の
操業方法である。特に、上記操業方法において、中細ノ
ズルで形成される超音速酸素ガス流を、炉内の溶鋼面高
さ位置で出鋼口側の炉壁直下位置、およびその位置から
炉中心側へ炉内径の２５％までの範囲を狙って噴出させ
ることが好ましい。SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to an eccentric furnace bottom tapping type electric furnace used for melting scrap and having a tapping port attached to a lower part of the tip of an electric furnace. In the operation method, a medium-thin nozzle having a throat at a water-cooled tip is installed on a water-cooled jacket on a tap hole upper wall, and oxygen gas is blown from the nozzle toward undissolved scrap near the tap hole. This is a method for operating an electric furnace, which is characterized in that the operation is as follows. In particular, in the above-mentioned operation method, the supersonic oxygen gas flow formed by the small-diameter nozzle is caused to flow from the molten steel surface height position in the furnace to a position directly below the furnace wall on the tapping port side, and from that position to the furnace center side. It is preferable to squirt aiming at a range of up to 25%.
【００１３】[0013]
【発明の実施の形態】すなわち本発明は、出鋼口上部壁
の水冷ジャケットに設置した中細ノズルにより、酸素ガ
スを吹きこむので、ノズル直前には空隙が存在するため
跳ね返り酸素ガスの影響が軽減され、ノズル先端やその
周辺の構造物も溶損されないし、炉内の溶鋼溜りと未溶
解スクラップの境界を狙い酸素ガスを吹き込むことがで
きるゆえ、加熱されたスクラップの溶断とともに溶鋼の
撹拌を非常に効率的に実施でき、出鋼口側の溶解を促進
できる。DESCRIPTION OF THE PREFERRED EMBODIMENTS That is, according to the present invention, oxygen gas is blown in by a small-sized nozzle installed in a water-cooled jacket on the upper wall of a tapping outlet. This reduces the damage to the nozzle tip and the surrounding structure, and allows oxygen gas to be blown in at the boundary between the molten steel pool in the furnace and the unmelted scrap, so that the molten steel is stirred together with the melted heated scrap. It can be carried out very efficiently and promotes melting on the tapping side.
【００１４】特に、前記ノズルからの酸素ガス流は図３
に示した通り、炉内の溶鋼面高さ位置で出鋼口側の炉壁
直下位置、およびその位置から炉中心側へ炉内径の２５
％までの範囲の任意の個所を狙って噴出すれば効果的で
ある。また、その酸素ガス流は未溶解スクラップの溶断
と溶鋼の撹拌に適した超音速流とすることが好ましい。
加えて、前記ノズルは超音速の気流を形成させるため、
スロート部を有する中細ノズルとし、また、酸素ガス噴
出中の熱負荷を考慮し、銅製でノズルを構成し、水冷す
ることがノズル保護の観点から重要である。In particular, the flow of oxygen gas from the nozzle is shown in FIG.
As shown in the above, at the molten steel surface height position in the furnace, a position immediately below the furnace wall on the tapping side, and 25 mm of the furnace inner diameter from that position to the furnace center side.
It is effective to squirt at any point in the range up to%. Further, it is preferable that the oxygen gas flow is a supersonic flow suitable for melting the undissolved scrap and stirring the molten steel.
In addition, the nozzle creates a supersonic airflow,
It is important from the viewpoint of protecting the nozzle that the nozzle is made of copper in consideration of the heat load during the jetting of oxygen gas, and that the nozzle is made of water in consideration of the heat load during the jetting of oxygen gas.
【００１５】[0015]
【実施例】以下に、本発明を実施例に基づいて更に詳細
に説明する。図１は本発明の操業に使用する直流電気炉
の例を一部断面にして示した。本発明はこれに限定され
ず、交流電気炉にも有効であることは言うまでもない。
図１において、炉本体１の炉壁内面には水冷パネル２、
耐火物３が内張りされており、炉本体１の上部には炉内
に溶解精錬するスクラップを装入するために開閉可能な
炉蓋４が配置されている。炉底部分には炉底電極５が配
置され、上方に昇降可能に設けた黒鉛電極６との間でア
ークを発生させスクラップの溶解を行なう。また溶解作
業を効率的におこなうために開閉可能な扉７ａを装備し
た作業口７から酸素ガスおよび炭素粉を吹き込むことが
できるランス７ｂ，７ｃを作業床に配置し、作業口７の
反対側には出鋼口８が配置されている。また、水冷パネ
ルの複数箇所に可燃ガスと酸素ガスを用いたバーナー９
を配置している。The present invention will be described in more detail with reference to the following examples. FIG. 1 shows an example of a DC electric furnace used in the operation of the present invention in a partial cross section. The present invention is not limited to this, and it goes without saying that the present invention is also effective for an AC electric furnace.
In FIG. 1, a water-cooled panel 2 is provided on an inner surface of a furnace wall of a furnace body 1.
A refractory 3 is lined, and a furnace lid 4 that can be opened and closed for charging scrap to be melted and refined in the furnace is disposed at an upper portion of the furnace body 1. A furnace bottom electrode 5 is arranged on the furnace bottom portion, and an arc is generated between the furnace bottom electrode 5 and a graphite electrode 6 which can be raised and lowered to melt the scrap. In addition, lances 7b and 7c through which oxygen gas and carbon powder can be blown from a working port 7 equipped with a door 7a which can be opened and closed to efficiently perform the melting operation are arranged on the working floor. Is provided with a tapping port 8. In addition, a burner 9 using flammable gas and oxygen gas at a plurality of locations of the water cooling panel.
Has been arranged.
【００１６】本発明においては、出鋼口８の上部に設置
された水冷溝１０ａを有する水冷ジャケット１０に、酸
素ガスのみを吹き込むことができる水冷銅製の酸素ノズ
ル１１を配置した。酸素ノズル１１はスクラップの溶断
と溶鋼の撹拌強化を主眼とし、ノズル形状は図２に示す
ように、スロート１２を有する中細ノズルを採用し、超
音速の酸素ガス流速を実現できる仕様とした。また、酸
素ガス噴出中の熱負荷を考慮し、銅製で循環冷却水路１
３を形成する構成としてノズル保護している。酸素ノズ
ル１１は、水冷ジャケット１０に取付治具（図示せず）
を介してノズル傾斜角を調整可能に取り付け、ノズルの
先端部分は上部炉壁より炉内側に過度に突き出ない位
置、好ましくは上部炉壁側に突き出ない位置に設定する
ことが好ましい。In the present invention, a water-cooled copper oxygen nozzle 11 capable of injecting only oxygen gas is disposed in a water-cooled jacket 10 having a water-cooled groove 10a provided above the tapping port 8. The oxygen nozzle 11 is mainly designed to melt the scrap and strengthen the agitation of the molten steel. As shown in FIG. 2, the oxygen nozzle 11 employs a medium-thin nozzle having a throat 12 and has a specification capable of realizing a supersonic oxygen gas flow rate. Also, in consideration of the heat load during the jetting of oxygen gas, the circulating cooling channel 1 is made of copper.
No. 3 is protected by nozzle protection. The oxygen nozzle 11 is attached to the water cooling jacket 10 by a jig (not shown).
It is preferable that the nozzle tilt angle is adjustable via the nozzle, and the tip portion of the nozzle is set to a position that does not excessively protrude into the furnace from the upper furnace wall, preferably a position that does not protrude toward the upper furnace wall.
【００１７】本発明の電気炉では、溶解期の途中から炉
内の溶鋼溜りと未溶解スクラップの境界を狙って酸素ノ
ズル１１から酸素ガスを炉中心側へ、好ましくは図３に
示すように炉内径の２５％範囲内に吹き込み、加熱され
たスクラップの溶断とともに溶鋼の撹拌を効率的に行う
ことを狙うものとした。未溶解スクラップを溶断するこ
とにより、更に上方のスクラップが落下し、引き続き超
音速酸素ガス流によって溶断され、溶鋼溜り中に未溶解
スクラップが浸漬していく。この際、ノズル先端は炉壁
より外側にあるため、スクラップの落下等で損傷するこ
とはない。また、未溶解スクラップが浸漬した溶鋼面に
は前記の超音速酸素ガス流が衝突しているゆえ、その撹
拌効果によって、未溶解スクラップの溶解速度は大幅に
向上する。In the electric furnace of the present invention, the oxygen gas is supplied from the oxygen nozzle 11 to the furnace center side in the middle of the melting period, aiming at the boundary between the molten steel reservoir and the unmelted scrap in the furnace, preferably as shown in FIG. Blowing was performed within a range of 25% of the inner diameter, so that the molten steel was melted and the molten steel was stirred efficiently. By fusing the unmelted scrap, the scrap further above falls, and is further melted and cut by the supersonic oxygen gas flow, so that the unmelted scrap is immersed in the molten steel pool. At this time, since the tip of the nozzle is located outside the furnace wall, there is no damage due to scrap falling or the like. Further, since the supersonic oxygen gas flow collides with the molten steel surface in which the undissolved scrap is immersed, the dissolution rate of the undissolved scrap is greatly improved by the stirring effect.
【００１８】本発明において、酸素ノズルから噴出する
酸素ガス流を超音速以上にするのが好ましいとしたの
は、それ未満ではスクラップの溶断・溶解を短時間に行
い、より効率的な操業を行うのが難しくなるからであ
る。また、超音速酸素ガス流を、炉内の溶鋼面高さ位置
で出鋼口側の炉壁直下位置、およびその位置から炉中心
側へ炉内径の２５％までの範囲としたのは、未溶解スク
ラップの残留がこの範囲で多いことによる。In the present invention, it is preferable that the oxygen gas flow ejected from the oxygen nozzle is supersonic or higher. If the oxygen gas flow is less than the supersonic speed, the cutting and melting of the scrap are performed in a short time, and more efficient operation is performed. It becomes difficult. It is not yet possible to set the supersonic oxygen gas flow to a position just below the furnace wall on the tapping side at the molten steel surface height position in the furnace and a range from that position to the furnace center side up to 25% of the furnace inner diameter. This is due to the large amount of dissolved scrap remaining in this range.
【００１９】以下に本発明の操業例を説明する。図１に
示す偏芯炉底出鋼方式の電気炉（容量１３７トン）にス
クラップを１４９トン装入し、生産量１トンあたりの酸
素ガス量、可燃性ガス量等の補助エネルギー量を等しく
なるようにして、溶解期中期から精錬期末期までの約２
０分間、酸素ノズル１１から送酸速度１０００Nm3 ／
ｈ、中細ノズルのスロート直前の設計圧力７．５kg／cm
2 Ｇの条件で酸素ガスを吹き込んだ。酸素ガスを吹き込
まない間は、ノズル内部への異物詰まりの対策として窒
素ガスを常時４００Nm3 ／ｈで吹き込むこととした。Hereinafter, an operation example of the present invention will be described. 149 tons of scrap are charged into the eccentric hearth tapping type electric furnace (capacity: 137 tons) shown in FIG. 1, and the amount of auxiliary energy such as the amount of oxygen gas and the amount of flammable gas per ton of production is equalized. Thus, from the middle of the melting period to the end of the refining period, about 2
Oxygen sending speed from oxygen nozzle 11 for 1000 minutes 1000 Nm 3 /
h, Design pressure 7.5 kg / cm just before throat of medium / small nozzle
Oxygen gas was blown under 2 G conditions. While oxygen gas was not blown, nitrogen gas was blown constantly at 400 Nm 3 / h as a measure against clogging of foreign matter inside the nozzle.
【００２０】また酸素ガスは、炉内の溶鋼面高さ位置で
出鋼口側の炉壁直下位置から炉中心側へ炉内径の約５％
に相当する３００mmの位置を狙って、下向き４０°の角
度で超音速流で吹き込んだ。その結果、本発明の方法を
採用しない場合に比べ、電力原単位と溶解時間ともに５
％改善することができた。また、従来の技術では問題と
なっていたノズル本体やその周辺構造物の溶損、ノズル
の詰まりの問題も無く、安定的にその効果を発揮できる
ことが確認できた。Oxygen gas is about 5% of the inner diameter of the furnace from the position just below the furnace wall on the tapping outlet side to the center of the furnace at the molten steel surface height position in the furnace.
Aiming at a position of 300 mm corresponding to, the air was blown in a supersonic flow at an angle of 40 ° downward. As a result, as compared with the case where the method of the present invention is not employed, both the power consumption unit and the dissolution time are 5 times.
% Could be improved. In addition, it was confirmed that there was no problem of erosion of the nozzle body and its peripheral structures and nozzle clogging which were problems in the conventional technology, and that the effects could be exhibited stably.
【００２１】[0021]
【発明の効果】以上説明したように、本発明の電気炉を
使用することにより、バーナー先端やその周辺設備の損
傷が発生することなく、効率的なスクラップの溶断と溶
鋼の撹拌強化をおこなうことができ、結果として溶解が
遅れる出鋼口側の溶解速度を高めることができる。これ
によって、電力原単位ならびに溶解時間を大幅に改善す
ることができる。As described above, by using the electric furnace of the present invention, it is possible to efficiently melt the scrap and strengthen the stirring of the molten steel without causing damage to the tip of the burner and the peripheral equipment. As a result, the melting speed on the tapping port side where the melting is delayed can be increased. As a result, the power consumption and dissolution time can be significantly improved.
【図１】本発明にかかわる酸素ノズルを配置した電気炉
を示す部分断面面である。FIG. 1 is a partial sectional view showing an electric furnace in which an oxygen nozzle according to the present invention is arranged.
【図２】本発明にかかわる酸素ノズルの配置を示す拡大
説明図面である。FIG. 2 is an enlarged explanatory drawing showing an arrangement of oxygen nozzles according to the present invention.
【図３】本発明にかかわる酸素ノズルから噴出させる酸
素ガス流の狙い位置を示す説明図であり、（ａ）は断
面、（ｂ）は平面を示す。FIGS. 3A and 3B are explanatory diagrams showing target positions of an oxygen gas flow ejected from an oxygen nozzle according to the present invention, wherein FIG. 3A shows a cross section and FIG.
【図４】従来の電気炉操業における溶解不良部位を表し
た部分断面説明図面である。FIG. 4 is a partial cross-sectional explanatory drawing showing a poorly melted portion in a conventional electric furnace operation.
１ 電気炉本体 ２ 水冷パネル ３ 耐火物 ４ 炉蓋 ５ 炉底電極 ６ 黒鉛電極 ７ 作業口 ８ 出鋼口 ９ バーナー １０ 出鋼口上部の水冷ジャケ
ット １１ 酸素ノズル １２ スロート部 １３ 循環冷却水路REFERENCE SIGNS LIST 1 Electric furnace main body 2 Water cooling panel 3 Refractory 4 Furnace lid 5 Furnace bottom electrode 6 Graphite electrode 7 Work port 8 Tapping tap 9 Burner 10 Water cooling jacket above tapping tap 11 Oxygen nozzle 12 Throat section 13 Circulating cooling water channel
─────────────────────────────────────────────────────
────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成１２年２月４日（２０００．２．４）[Submission date] February 4, 2000 (200.2.4)
【手続補正１】[Procedure amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】特許請求の範囲[Correction target item name] Claims
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【特許請求の範囲】[Claims]
【手続補正２】[Procedure amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１２[Correction target item name] 0012
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【００１２】[0012]
【課題を解決するための手段】上記目的を達成するため
本発明は、スクラップの溶解に使用し、出鋼口が電気炉
の先端下部に取り付けられている偏芯炉底出鋼方式の電
気炉の操業方法において、出鋼口上部壁の水冷ジャケッ
トに、水冷式の先端部にスロートを有する中細ノズル
を、該ノズルの傾斜角を調整可能にすると共に、その先
端部が上部炉壁より炉内側に突出させない位置に設け、
該ノズルで形成される超音速酸素ガス流を、炉内の溶鋼
面高さ位置で出鋼口側の炉壁直下位置、およびその位置
から炉中心側へ炉内径の２５％までの範囲を狙って噴出
させることを特徴とする電気炉の操業方法である。 SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to an eccentric furnace bottom tapping type electric furnace used for melting scrap and having a tapping port attached to a lower part of the tip of an electric furnace. In the operation method of the above, the water-cooled jacket of the tap hole upper wall, a water-cooled medium-thin nozzle having a throat at the tip
Is adjusted so that the inclination angle of the nozzle can be adjusted,
The end is provided at a position that does not protrude inside the furnace from the upper furnace wall,
The supersonic oxygen gas flow formed by the nozzle is aimed at a position just below the furnace wall on the tapping port side at the molten steel surface height position in the furnace and a range from that position to the furnace center side up to 25% of the furnace inner diameter. It is a method for operating an electric furnace, characterized in that the electric furnace is ejected .
【手続補正３】[Procedure amendment 3]
【補正対象書類名】図面[Document name to be amended] Drawing
【補正対象項目名】図４[Correction target item name] Fig. 4
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【図４】 FIG. 4
Claims (2)
気炉の先端下部に取り付けられている偏芯炉底出鋼方式
の電気炉の操業方法において、出鋼口上部壁の水冷ジャ
ケットに、水冷式の先端部にスロートを有する中細ノズ
ルを設置し、該ノズルより、出鋼口近傍の未溶解スクラ
ップに向けて酸素ガスを吹きこむことを特徴とする電気
炉の操業方法。1. A method for operating an eccentric furnace bottom tapping type electric furnace which is used for melting a scrap and has a tapping hole attached to a lower part of the tip of the electric furnace, wherein a water cooling jacket on an upper wall of the tapping port is provided. A method for operating an electric furnace, comprising: installing a medium-thin nozzle having a throat at a water-cooled tip, and blowing oxygen gas from the nozzle toward undissolved scrap near a tapping port.
気炉の先端下部に取り付けられている偏芯炉底出鋼方式
の電気炉の操業方法において、出鋼口上部壁の水冷ジャ
ケットに、水冷式の先端部にスロートを有する中細ノズ
ルを設け、該ノズルで形成される超音速酸素ガス流を、
炉内の溶鋼面高さ位置で出鋼口側の炉壁直下位置、およ
びその位置から炉中心側へ炉内径の２５％までの範囲を
狙って噴出させることを特徴とする電気炉の操業方法。2. A method for operating an eccentric furnace bottom tapping type electric furnace which is used for melting of scrap and has a tapping hole attached to a lower portion of the tip of the electric furnace, wherein a water cooling jacket on an upper wall of the tapping port is provided. Provide a medium-thin nozzle having a throat at the tip of a water-cooled type, the supersonic oxygen gas flow formed by the nozzle,
A method for operating an electric furnace, characterized in that a jet is blown from a position just below a furnace wall on a tapping side at a molten steel surface height position in a furnace and from the position to a furnace center side in a range of up to 25% of a furnace inner diameter. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15671699A JP2000345230A (en) | 1999-06-03 | 1999-06-03 | Operation method of electric furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15671699A JP2000345230A (en) | 1999-06-03 | 1999-06-03 | Operation method of electric furnace |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000345230A true JP2000345230A (en) | 2000-12-12 |
Family
ID=15633785
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15671699A Pending JP2000345230A (en) | 1999-06-03 | 1999-06-03 | Operation method of electric furnace |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000345230A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009052781A (en) * | 2007-08-24 | 2009-03-12 | Sanyo Special Steel Co Ltd | Auxiliary combustion equipment for steel furnaces |
| KR101087125B1 (en) | 2008-12-24 | 2011-11-25 | 현대제철 주식회사 | Furnace Burner Device |
| CN103014231A (en) * | 2012-12-28 | 2013-04-03 | 攀枝花钢城集团瑞钢工业有限公司 | Oxygen supplying method for smelting slag steel and slag iron by electric arc furnace |
-
1999
- 1999-06-03 JP JP15671699A patent/JP2000345230A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009052781A (en) * | 2007-08-24 | 2009-03-12 | Sanyo Special Steel Co Ltd | Auxiliary combustion equipment for steel furnaces |
| KR101087125B1 (en) | 2008-12-24 | 2011-11-25 | 현대제철 주식회사 | Furnace Burner Device |
| CN103014231A (en) * | 2012-12-28 | 2013-04-03 | 攀枝花钢城集团瑞钢工业有限公司 | Oxygen supplying method for smelting slag steel and slag iron by electric arc furnace |
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