JP2912834B2 - Steelmaking method using electric furnace - Google Patents
Steelmaking method using electric furnaceInfo
- Publication number
- JP2912834B2 JP2912834B2 JP24533294A JP24533294A JP2912834B2 JP 2912834 B2 JP2912834 B2 JP 2912834B2 JP 24533294 A JP24533294 A JP 24533294A JP 24533294 A JP24533294 A JP 24533294A JP 2912834 B2 JP2912834 B2 JP 2912834B2
- Authority
- JP
- Japan
- Prior art keywords
- scrap
- hot metal
- electric furnace
- charged
- 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.)
- Expired - Lifetime
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
Description
【０００１】[0001]
【産業上の利用分野】本発明は、電気炉を用いてスクラ
ップを溶解する製鋼法の改良に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a steelmaking method for melting scrap using an electric furnace.
【０００２】[0002]
【従来の技術】電気炉にスクラップ等の固形原料を装入
して溶解する製鋼法は広く実施されている。かかる製鋼
法はスクラップ等の冷たい原料から操業を開始するた
め、その溶解に要する時間と電力エネルギーが大とな
る。そこで、この溶解に要する時間とエネルギーを節減
することが要請され、近年では固形原料のスクラップ等
の他に、溶銑を炉内に装入して生産性を向上し、省エネ
ルギーが図られている。このときの溶銑の配合率は、例
えば特開平６−４１６２７号公報によれば２０〜３０％
とされ、それ以上の溶銑の配合率はスクラップ等の固形
原料の溶解効率を低減されるとされている。又、特開昭
５７−４７８１５号公報によれば、電気炉への溶銑の装
入を炉下部からの撹拌ガスの吹込みにより溶融面をバブ
リング状態に保ち、溶銑との撹拌をスムースに行ない、
均一に混合せしめる方法が開示されている。この方法で
は溶銑を全装入物の７０％を越えない割合となるように
して装入する。溶銑の量が７０％を越えると、炉壁耐火
物は次第に溶損され、凹陥部が生じる。この炉壁の凹陥
部に高炭素含量の溶銑が浸入すると脱炭などの精錬が行
なわれにくく、最終溶鋼の品質が低下する。2. Description of the Related Art Steelmaking methods in which a solid material such as scrap is charged into an electric furnace and melted are widely practiced. In such a steelmaking method, since the operation is started from a cold raw material such as scrap, the time required for melting and the power energy are increased. Therefore, it is required to reduce the time and energy required for the melting, and in recent years, in addition to scraps of solid raw materials and the like, hot metal is charged into a furnace to improve productivity and save energy. The mixing ratio of the hot metal at this time is, for example, 20 to 30% according to JP-A-6-41627.
It is said that the higher the mixing ratio of the hot metal, the lower the melting efficiency of the solid material such as scrap. According to Japanese Patent Application Laid-Open No. 57-47815, charging of molten metal into an electric furnace is performed by blowing a stirring gas from a lower part of the furnace to keep a molten surface in a bubbling state, and smoothly stirring the molten metal with the molten iron.
A method of uniformly mixing is disclosed. In this method, hot metal is charged so as not to exceed 70% of the total charge. When the amount of hot metal exceeds 70%, the furnace wall refractory is gradually melted and a depression is formed. If molten iron having a high carbon content enters the recessed portion of the furnace wall, refining such as decarburization is difficult to be performed, and the quality of the final molten steel is reduced.
【０００３】[0003]
【発明が解決しようとする課題】本発明は、溶銑の配合
率をさらに増加させて溶銑潜熱の効率利用を図っても、
溶鋼の品質が低下することなく、さらに脱炭時の発熱を
利用し、生産性を向上させるものである。又、鋼不純物
の低下を図り、低級スクラップでも有効に再利用するこ
とができるようにするものである。According to the present invention, even if the mixing ratio of the hot metal is further increased to achieve efficient use of the latent heat of the hot metal,
Without quality soluble steel is lowered, and further use of the heat generated during decarburization, and improves the productivity. Further, steel impurities are reduced so that even low-grade scrap can be effectively reused.
【０００４】[0004]
【課題を解決するための手段】本発明は、電気炉にスク
ラップ等の原料と共に、溶銑を全装入物の３０〜８５％
の割合で、その装入時期をスクラップ溶解率３０〜４０
％の段階として、炉頂から炉の中心部におけるスクラッ
プが溶け落ちしてスクラップなどの固形原料に囲まれた
部分に装入し、酸素を供給してその反応熱を利用して溶
解する電気炉による製鋼方法である。すなわち、本発明
は装入する溶銑の量を３０〜８５％と増加させることに
より、溶銑の潜熱により電気炉の電力使用量の低減を図
り、又、酸素を使用することにより、酸素による脱炭を
図りながら、ＣＯ，ＣＯ2の反応熱を利用して生産性の
一層の向上を図る。溶銑の量を増加することにより、溶
鋼の不純物レベルを低下させることができるので低級ス
クラップの配合量を高めることができる。溶銑の電気炉
への装入を炉頂から炉の中心部のスクラップなどの固形
原料の中心部にすることによって、溶銑による炉壁の損
傷をなくし、結果的に不純物の低減を図ることができ
る。SUMMARY OF THE INVENTION The present invention relates to an electric furnace in which hot metal is mixed with raw materials such as scrap in an amount of 30 to 85% of the total charge.
, And the charging time is set to a scrap dissolution rate of 30 to 40.
As% stage, scrap from the furnace top at the center portion of the furnace
The melt is melted down and charged into the area surrounded by the solid material such as scrap , and oxygen is supplied and the heat of reaction is used to melt it.
A steelmaking process by electric furnace for solution. That is, the present invention aims to reduce the electric power consumption of the electric furnace by the latent heat of the hot metal by increasing the amount of the hot metal to be charged to 30 to 85%, and decarbonization by oxygen by using oxygen. While improving the productivity by utilizing the reaction heat of CO and CO 2 . By increasing the amount of hot metal,
Since the impurity level of steel can be reduced, the amount of low-grade scrap can be increased. By placing the hot metal into the electric furnace from the furnace top to the center of the solid material such as scrap in the center of the furnace, damage to the furnace wall due to the hot metal can be eliminated and consequently impurities can be reduced .
【０００５】溶銑の装入量が全装入量の３０％未満であ
ると、電力の使用量の低減が不十分で、又、不純物低減
の効果も十分ではなくなる。８５％を超える量となる
と、スクラップの再利用の目的が十分果せなくなる。最
も効果的な範囲は４０〜７２％である。また、発明者等
は溶銑の量を７２〜８５％の高配合率でも溶銑溶鋼の
〔Ｃ〕差、温度差による急激反応をスクラップ溶綱中へ
の炭粉切込みおよびＡｌショット吹込による脱酸をはか
ることにより抑制する技術を見出した。溶銑の装入時期
は、スクラップ等固形原料の溶解率が３０〜４０％の段
階が良い。固形原料の溶解率が３０％未満の段階で溶銑
を装入すると、スクラップ溶解効率、溶銑の潜熱回収が
低下し生産性が低下し、又、溶解率が４０％を超える段
階で装入すると、溶銑と溶鋼の温度差、〔Ｃ〕差による
急激反応が生じ、溶銑のトップチャージが困難となり、
いずれも好ましくない。[0005] If the charged amount of hot metal is less than 30% of the total charged amount, the reduction of the power consumption is insufficient and the effect of reducing impurities is not sufficient. If the amount exceeds 85%, the purpose of scrap recycling cannot be sufficiently achieved. The most effective range is 40-72%. Further, inventors have deoxidized by anthracosis cuts and Al shot blow the [C] difference molten iron soluble steels with a high content rate of 72 to 85% the amount of hot metal, the rapid reaction due to the temperature difference into the scrap溶綱We found a technique to suppress it by measuring it. The charging time of the hot metal is preferably such that the melting ratio of the solid material such as scrap is 30 to 40%. If the molten metal is charged at a stage where the dissolution rate of the solid raw material is less than 30%, the scrap melting efficiency and the latent heat recovery of the molten iron are reduced to lower the productivity, and if the molten metal is charged at a stage where the dissolution rate exceeds 40%, A rapid reaction occurs due to the temperature difference between the hot metal and the steel, the difference in [C], making it difficult to top-charge the hot metal,
Neither is preferred.
【０００６】酸素を使用すると前述のように、Ｃ＋Ｏ2
→ＣＯｏｒＣＯ2の反応が起り、脱炭を図りながら、そ
の反応熱をスクラップ等の溶解に有効に利用することが
できる。酸素の装入箇所は、操作口からマニプレーター
装置を用いて炉中に供給するのが良い。When oxygen is used, as described above, C + O 2
→ The reaction of COorCO 2 occurs, and the heat of the reaction can be effectively used for dissolving scrap and the like while decarburizing. It is preferable to supply oxygen into the furnace from the operation port using a manipulator device.
【０００７】[0007]
実施例１ 図１に示す出鋼量１００ｔの直流電気炉装置を用いて実
施した。１は電気炉で、２はレードルであり、炉蓋、電
気を切った電極を旋回所定の位置まで旋回し高炉よりの
溶銑を装入して、バケットクレーン４により電気炉室内
に搬入する。３はクレーン４上に設けた自走車で、レー
ドル２を、電気炉１の近傍まで移動させ、適宜位置で傾
斜して、内部の溶銑を電気炉１のほぼ中央部のスクラッ
プ等５の固形原料で囲まれた部分に装入する。Example 1 The test was carried out using a DC electric furnace having a tapping amount of 100 tons as shown in FIG. Reference numeral 1 denotes an electric furnace, and reference numeral 2 denotes a ladle. The furnace cover and the electrode whose electric power has been turned are swirled to a predetermined position, charged with hot metal from a blast furnace, and carried into the electric furnace chamber by a bucket crane 4. Reference numeral 3 denotes a self-propelled vehicle provided on a crane 4 for moving the ladle 2 to the vicinity of the electric furnace 1 and inclining it at an appropriate position so that the molten metal inside the electric furnace 1 can be solidified in a scrap 5 or the like in a substantially central portion of the electric furnace 1. Charge the parts surrounded by the raw materials.
【０００８】スクラップ５を６０ｔおよび石灰１．８ｔ
を電気炉１に装入後、スクラップ５が３０％溶解した時
点で、レードル２から溶銑６０ｔを炉頂中心部から装入
した。溶銑中Ｃの反応に必要な酸素および脱燐に必要な
スラグ中の酸素を操作口からマニプレーター装置を用い
て炉中へ５０００Ｎｍ3／Ｈｒの送酸量にて、１５Ｎｍ3
／Ｔ送酸した。脱炭素および脱燐の結果を経時的に図２
の実線グラフで示した。図２から判るように、溶銑中の
Ｃ２．２％とＰ０．０３４％は、酸素１５Ｎｍ3／Ｔ供
給することにより、Ｃ０．２％、Ｐ０．０１％まで減少
した。[0008] 60 tons of scrap 5 and 1.8 tons of lime
Was charged into the electric furnace 1 and when the scrap 5 was melted by 30%, 60 t of hot metal was charged from the ladle 2 from the center of the furnace top. The oxygen required for the reaction of C in the hot metal and the oxygen in the slag required for the dephosphorization were introduced into the furnace from the operation port using a manipulator device at an acid feed rate of 5000 Nm 3 / Hr at 15 Nm 3.
/ T was fed. FIG. 2 shows the results of decarbonization and dephosphorization over time.
Is shown by a solid line graph. As can be seen from FIG. 2, C2.2% and P0.034% in the hot metal were reduced to C0.2% and P0.01% by supplying 15 Nm 3 / T of oxygen.
【０００９】実施例２ 実施例１と同様に、図１に示す出鋼量１００ｔ直流電気
炉装置を用いて実施した。スクラップ５を３０ｔおよび
生石灰２．４ｔを電気炉１に装入後通電し、スクラップ
５が３５％溶解した時点で溶銑９０ｔを炉頂中心部から
装入した。スクラップ５が完全溶解後、炭粉５ｋｇ／Ｔ
およびＡｌショット２ｋｇ／Ｔを吹込み、続いて７５０
０Ｎｍ3／Ｈｒの送酸量にて２０Ｎｍ3／Ｔ送酸し、脱炭
精錬を施したが、急激な脱炭反応や炉壁が特に侵蝕され
ることもなかった。脱炭および脱燐の結果を経時的に図
２の点線のグラフで示した。溶銑のＣ３．０５％、Ｐ
０．０３９％は酸素２０Ｎｍ3／Ｔ供給することによ
り、出鋼時にはＣ０．２％、Ｐ０．０１０％まで減少し
た。Example 2 In the same manner as in Example 1, the test was carried out by using a DC electric furnace with a tapping amount of 100 t shown in FIG. After charging 30 tons of scrap 5 and 2.4 tons of quick lime to the electric furnace 1, electricity was supplied. When 35% of the scrap 5 was melted, 90 tons of hot metal was charged from the center of the furnace top. After scrap 5 is completely dissolved, charcoal powder 5kg / T
And 2 kg / T of Al shot, followed by 750
20 Nm 3 / T was fed at a feed rate of 0 Nm 3 / Hr, and decarburization was performed, but no rapid decarburization reaction and no erosion of the furnace wall was observed. The results of the decarburization and dephosphorization are shown over time in a dotted line graph in FIG. 3.05% of hot metal, P
By supplying 20 Nm 3 / T of oxygen, 0.039% was reduced to 0.2% of C and 0.010% of P during tapping.
【００１０】[0010]
【発明の効果】本発明は、溶銑の配合率をさらに増加さ
せて溶銑潜熱の効率利用を図り、溶鋼の品質が低下する
ことなく、さらに脱炭反応の発熱を利用して生産性を向
上させる。又、鋼不純物の低下を図り、低級スクラップ
でも有効に再利用することが可能となる。According to the present invention, the compounding ratio of the hot metal is further increased to utilize the latent heat of the hot metal efficiently, and the productivity of the steel is improved by using the heat generated by the decarburization reaction without lowering the quality of the molten steel. . In addition, steel impurities can be reduced, and even low-grade scrap can be effectively reused.
【図１】本発明を実施するに適した装置の説明図であ
る。FIG. 1 is an explanatory diagram of an apparatus suitable for carrying out the present invention.
【図２】実施例における脱炭、脱燐効果を示すグラフで
ある。FIG. 2 is a graph showing decarburization and dephosphorization effects in Examples.
１ 電気炉 ２ レードル ３ 自走車 ４ クレーン ５ スクラップ等 1 electric furnace 2 ladle 3 self-propelled vehicle 4 crane 5 scrap etc.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) C21C 5/52 C22B 9/16 F27B 3/08 F27D 11/08 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 6 , DB name) C21C 5/52 C22B 9/16 F27B 3/08 F27D 11/08
Claims (2)
銑を全装入物の３０〜８５％の割合で、その装入時期を
スクラップ溶解率３０〜４０％の段階として、炉頂から
炉の中心部におけるスクラップが溶け落ちしてスクラッ
プなどの固形原料に囲まれた部分に装入し、酸素を供給
してその反応熱を利用して溶解することを特徴とする電
気炉による製鋼方法。1. An electric furnace together with raw materials such as scrap is charged with hot metal at a rate of 30 to 85% of the total charge, and the charging time is set at a stage of a scrap melting rate of 30 to 40%. Scrap in the center melts down and is charged into the area surrounded by solid materials such as scrap and supplies oxygen
And melting by utilizing the heat of reaction .
装入する場合、その急激反応をスクラップ溶鋼中へ炭粉
吹込みおよびＡｌショット吹込みにて抑制する請求項１
記載の電気炉による製鋼方法。2. When the hot metal is charged at a rate of 72 to 85% of the total charge, the rapid reaction is suppressed by blowing coal powder and Al shot into molten steel scrap.
The steel making method using the electric furnace described in the above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24533294A JP2912834B2 (en) | 1994-10-11 | 1994-10-11 | Steelmaking method using electric furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24533294A JP2912834B2 (en) | 1994-10-11 | 1994-10-11 | Steelmaking method using electric furnace |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08109408A JPH08109408A (en) | 1996-04-30 |
| JP2912834B2 true JP2912834B2 (en) | 1999-06-28 |
Family
ID=17132096
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24533294A Expired - Lifetime JP2912834B2 (en) | 1994-10-11 | 1994-10-11 | Steelmaking method using electric furnace |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2912834B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100431865B1 (en) * | 2000-11-27 | 2004-05-20 | 주식회사 포스코 | A method for operating electric arc furnace using hot melt |
| JP4097010B2 (en) | 2001-05-29 | 2008-06-04 | 大同特殊鋼株式会社 | Molten steel manufacturing method |
-
1994
- 1994-10-11 JP JP24533294A patent/JP2912834B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08109408A (en) | 1996-04-30 |
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