JPS60221511A - Method for carburizing and melt-refining molten iron - Google Patents

Abstract

PURPOSE:To maximize the thermal efficiency of a carbon source added by specifying the grain size of a substance contg. carbon and a method for blowing the substance when the substance is added to a composite refining apparatus to increase thermal tolerance. CONSTITUTION:A substance contg. C is blown on the surface of molten iron in a vessel from a position above the surface of the molten iron through a lance while blowing a gas generating substance from the bottom of the vessel and gaseous O2 from the top to carry out composite refining. Grains of 1-10mm. grain size account for >=70% of all the grains of the substance contg. C, and this C cource is blown on the surface of the central part of the molten iron from the central part of the lance so that the blowing region does not overlap the fire spot of a jet of O2 for refining by >=30%. In carburization and decarburization periods, the ratio of the area (m<2>) of the fire spot of gaseous O2 for refining to the surface area (m<2>) of the bath is kept at >0.4.

Description

【発明の詳細な説明】 （利用分野） 本発明は溶鉄の加炭溶解精錬法に関するものである。[Detailed description of the invention] (Application field) The present invention relates to a method for carburizing, melting, and refining molten iron.

（従来技術） 複合精錬容器にて容器上方又は上方精錬用ランスから、
炭素含有物質を添加する方法によって、搏枯惣肥由１／
鋪嶺ル祈４萌１赴酬炊面シ宜払　ブカラップを多量使用
する方法が、例えば特開昭５８−１１７１０号公報で知
られている。(Prior art) From the upper part of the container or the upper refining lance in the composite refining container,
Depending on the method of adding carbon-containing substances, it is possible to
A method of using a large amount of Bucharap is known, for example, from Japanese Patent Application Laid-Open No. 11710/1983.

ところで本発明者の検討によると、容器の上方から炭素
源を散布装入する方式では、上方から装入された炭素含
有物質は、溶銑と直接反応し、溶鉄中に加炭されるチャ
ンスが極めて少なく、大半かスラグ表層部に浮上した状
態となり、スラグ表；一部で、上方から吹製される敵累
カスによって、燃焼反応をおこすため、添加された炭素
源の燃焼による熱が溶鉄に伝わりにくく、大半が排ガス
中に逃げていく結果となる。即ち、添ガｉ１した炭素源
の；？ｊ（効率が極めて悪い。且つバラツキが太き見゛
ため、：雨銖炉の吹止割物１上も問題となる。However, according to the inventor's study, in the method of scattering and charging the carbon source from above the container, the carbon-containing material charged from above has a very high chance of directly reacting with the molten iron and being carburized into the molten iron. Most of the slag floats on the surface of the slag; a part of the slag surface is blown from above, causing a combustion reaction, so the heat from the combustion of the added carbon source is transferred to the molten iron. The result is that most of it escapes into the exhaust gas. That is, the carbon source added with i1; (Efficiency is extremely low. Also, the dispersion is large.) The blow-stop part 1 of the rain furnace also becomes a problem.

又容器の上方からランスによって圧力下に吹き込む方式
は、精錬用１波素ガスと同じ上方から炭素類を吹き込む
為、炭素Ｗは吹込みランスの先端かしく４銑表面にとど
くまでに、極めて高温で且つ酸系ガス気流中を通過する
必要があり、一般的には（谷銑面までに炭素源が到達す
るまでに、相当量の炭素が溶銑面上１Ｎｌｌを間で燃焼
してしまうため、充分な効率を得られない。In addition, in the method of blowing under pressure from above the container with a lance, carbon is injected from above in the same way as the first-wave elementary gas for refining, so the carbon W reaches an extremely high temperature before reaching the tip of the blowing lance and the surface of the pig iron. In addition, it is necessary to pass through an acidic gas stream, and generally (by the time the carbon source reaches the valley surface, a considerable amount of carbon burns 1 Nll above the hot metal surface, so efficiency cannot be obtained.

（発明の目的） 本発明は上述の課題を解決するものであって、その目的
は複合精錬装置において炭素含有物質を添加して、熱的
裕度な高めるに際し・添加した炭素源の熱効率を最高に
する加炭溶解；ｆげ錬法を提供するものである。(Object of the invention) The present invention solves the above-mentioned problems, and its purpose is to increase the thermal margin by adding a carbon-containing substance in a complex refining device, and to maximize the thermal efficiency of the added carbon source. The present invention provides a carburizing and melting method to produce carbon.

（発明の構成、作用、効果） 本発明の要旨は、容器下部からガス元生物質を吠き込み
、上方から醒累ガスを吹製し、倫鉄面上刃からランスに
より炭素含有物質を俗）じ面に吠き込む複合相線法にお
℃・て、炭素含有′＋／ｉ質の粒径が１１１ｉｉ１１−
　Ｉ　Ｑ　ｌ１ｌｌｉｌの範囲のものを少くとも７０％
以上占める炭素源を、鞘゛錬ば素ンエツトの火点面と３
０％以上交叉しない領域に、ランス中央部より溶鉄中央
部表面に吹き込み、かつ加炭期間及び脱炭期間は梢錬酸
素カス火点面積（ｉ）／浴衣面積（ｍ゛）＞０．４に維
持することを特徴とする。(Structure, operation, and effects of the invention) The gist of the present invention is to inject a gaseous substance from the lower part of the container, blow a liquid gas from above, and release a carbon-containing substance by a lance from an upper blade of a metal surface. ) According to the composite phase line method in the same plane, the particle size of carbon-containing '+/i is 111ii11- at °C.
IQ at least 70% in the l1llil range
The carbon source that occupies more than
The molten iron is blown from the center of the lance to the surface of the center of the molten iron in an area where there is no intersection of 0% or more, and during the carburization and decarburization periods, the treetop wrought oxygen gas ignition point area (i)/Yukata area (m゛)>0.4. It is characterized by maintaining.

以下本発明について詳述する。The present invention will be explained in detail below.

本発明は、炭素含有物質の粒径が１１１１１１１　１　
Ｑ　＋ＩＩ＋＋１の・碩−コを少（とも７０％以上占め
る炭素源を、精に’＋ｉ　’＃素ジェットの火点面と、
３０％以上交叉しない領域に加圧下で吹込むものである
が、これは次により理解される。In the present invention, the particle size of the carbon-containing substance is 1111111 1
Q +II++1's ・Sek-ko (carbon source that accounts for more than 70%) is precisely '+i'
This is to be blown under pressure into a region that does not intersect by more than 30%, which is understood as follows.

即し、吹き込みランスで炭素源を吹き込む場合、戻索ω
ｊ）か高温炉内で、精錬用酸素ガスと接触すると、急速
な燃焼がその場でおこるため、溶銑には炭素源のＣ十０
２→Ｃｏの燃焼熱の３０〜４０％程度か、反射伝熱とし
て伝わる程度であり、極めて熱効率の恋いものとなって
しまう。これを避ける方、去を（・ろいろテストの１貼
果、この解決は、吹き込み炭素′ｍ、粒子径と、炭素源
の吠き込まれる位置が」１／も重要な事が判った。Therefore, when blowing the carbon source with a blowing lance, the return cable ω
j) When hot metal comes into contact with oxygen gas for refining in a high-temperature furnace, rapid combustion occurs on the spot, so hot metal contains carbon source C10.
Only about 30 to 40% of the combustion heat of 2→Co is transmitted as reflected heat, resulting in extremely poor thermal efficiency. To avoid this, it was found that the solution to this problem is the injected carbon, the particle size, and the location where the carbon source is injected.

まず、炭素源の吹き込まれる位置と、吠き込まれた炭素
源の熱効率を第１図に示す。即ち第１図に示す通り、炭
素源の吹き込みガスの溶鉄表面での投影面が、精錬酸素
ガスの投影面と交叉する部分ａ１、ａ２が、２０％近傍
になると急激に炭素源のスクラップ＃屏能力（熱効率）
が低下することが第１図は、吠込み炭素源として４−６
ｍ径の無煙炭を用いた。又火点面積率（精錬酸素ガスの
浴表面上への投影面積／精錬容器の静止浴表面積）を０
６５に維持した。First, Figure 1 shows the position where the carbon source is injected and the thermal efficiency of the injected carbon source. That is, as shown in Fig. 1, when the portions a1 and a2 where the projected plane of the blown carbon source gas on the molten iron surface intersects the projected plane of the refined oxygen gas reach around 20%, the scrap # screen of the carbon source suddenly decreases. Capacity (thermal efficiency)
Figure 1 shows that 4-6 as a barking carbon source
Anthracite coal with a diameter of m was used. In addition, the firing point area ratio (projection area of refined oxygen gas onto the bath surface/stationary bath surface area of the refining vessel) is set to 0.
It was maintained at 65.

第２図は、溶鉄表面における炭素伏込み衝突面（Ｓ）が
、酸素ガス衝突面（Ｓ′）と交叉する面積率を示す模式
図である。FIG. 2 is a schematic diagram showing the area ratio where the carbon sinking collision surface (S) intersects with the oxygen gas collision surface (S') on the molten iron surface.

さらに第３図に精錬酸素ガスの投影面をさけた炉壁側に
、炭素源を吹き込んだ結果を示す。即ち楕釧販素ガス投
影面と、炭素源吹込ガス投影面と交叉しなくても、炉壁
側にはスラグが押しよせられた相当厚いスラグ層かある
ため、炭素源を溶銑の中まで浸入することが出来ず、ス
ラグ層の上で燃焼するため、熱効率が低いことが判った
。Furthermore, FIG. 3 shows the results of injecting a carbon source into the furnace wall side, avoiding the projected plane of the refined oxygen gas. In other words, even if the elliptical slag gas projection plane and the carbon source injection gas projection plane do not intersect, there is a fairly thick slag layer on the furnace wall side where the slag is pushed, so the carbon source can penetrate deep into the hot metal. It was found that the thermal efficiency was low because the combustion occurred on top of the slag layer.

第４図は炭素源吹込みランスと精錬用ば累ランスとの距
離Ｘを示す模式図である。FIG. 4 is a schematic diagram showing the distance X between the carbon source injection lance and the refining lance.

本発明における上述の溶鉄面上の炭素源吹込みガス衝突
面及び酸素ガス衝突面における各面積の計算は、次の式
によって与えられる。In the present invention, calculation of each area of the carbon source injected gas impingement surface and oxygen gas impingement surface on the molten iron surface is given by the following formula.

１ｍ　ｊｌＥ　；Ｉｉ　Ｖｆ　Ｑ　、２−　ｉｆＦ　＊
　Ｗ＋　踏１ｑｌ　＝　（’Ｉ）半Ｔ、　−Ｔ”Ｑ　ｎ
　７）　）胚Ｆ＞　構成−（盲酸素カス衝突面積（Ｓ′
）−ｒ＋Ｌ−Ｔａｎ（α＋β）径の面積−■又（Ｓ）の
中心点０と（Ｓ′）の点Ｐとの距離Ｘ＝　ａ＋Ｌ４ａｎ
（α−β）−■ 前記１．２及び３式の谷諸元を、第５図に示す。1m jlE ; Ii Vf Q , 2-ifF *
W+ step 1ql = ('I) half T, -T”Q n
7)) Embryo F> Composition - (blind oxygen sludge collision area (S'
)-r+L-Tan(α+β) diameter area-■Also, distance between center point 0 of (S) and point P of (S') X= a+L4an
(α-β)-■ The valley dimensions of equations 1.2 and 3 are shown in FIG.

図中２０はランス、２１は精錬酸素ノズル、Ｌはランス
湯面距離である。In the figure, 20 is a lance, 21 is a refining oxygen nozzle, and L is a lance surface distance.

次に炭素源の粒子の大きさと、スクラップ溶解１１ｇ力
との相関を第６図により明らかにする。Next, the correlation between the particle size of the carbon source and the scrap melting force of 11g is clarified using FIG.

第６図に示す様に、炭素源吹き込みガスと、精珠用戚素
ガスを交叉し１よい様に吹き込んでも、１＋ｊａｎ以下
の微粉炭素源が増加すると、吹き込みノズル先端部に１
置き状況が発生し、微粉炭素源と、酸素ガスの混合状態
がランス先端部分で発生し、その糺果、相当上部で炭素
源は燃焼してしまい、熱〃ｊ率が悪い結果となる。As shown in Fig. 6, even if the carbon source blowing gas and the spermatozoal relative gas are mixed and blown in at a rate of 1, if the fine carbon source of 1+jan or less increases, 1
When a situation occurs, a mixed state of the fine carbon source and oxygen gas occurs at the tip of the lance, and the carbon source burns at the top of the lance, resulting in a poor heat rate.

又］　Ｑ　１１３１１以上の大きい径のものは、粉体輸
送が困難で芙操業に適しない。Also, those with a large diameter of Q 11311 or more are difficult to transport as powder and are not suitable for fowl operation.

従って本発明における炭素含有物質の粒径を１−１０１
１１＋１１の範囲とする方が好ましい。Therefore, the particle size of the carbon-containing material in the present invention is 1-101
A range of 11+11 is preferable.

次に本発明においては、加炭期間及び脱炭期間は、精錬
酸素ガス火点面積（ｒｒｔ　）／浴面積（ｍ２）　＞　
０．４に維持する。経験によると、吹込み炭素源を溶銑
上方で燃焼させないで、いかに効率的に溶銑中に炭素源
を侵入させるかという点と、更に熱効率の向上を計るも
う一つの手段として、炭素源の燃焼を、ＣＯ２状態まで
実施させる事によって、ＣＯ状態までの時より約３倍の
発生熱を期待出来るので、いかに炉内でＣＯ２まで燃焼
させるか検討されなければならない。Next, in the present invention, the carburization period and the decarburization period are calculated as follows: Refined oxygen gas firing point area (rrt)/bath area (m2)>
Maintain at 0.4. According to experience, it is important to know how to efficiently infiltrate the carbon source into the hot metal without burning the injected carbon source above the hot metal, and as another means of improving thermal efficiency, combustion of the carbon source has been studied. By running the process up to the CO2 state, approximately three times as much heat can be expected to be generated as compared to when the CO2 state is reached, so consideration must be given to how to burn up to the CO2 state in the furnace.

本発明者はさきに溶銑の加炭溶解精錬方法（特願昭５７
−２３１２３２号）を提起して、溶銑浴深さくＬ）／溶
銑浴径（Ｄ）別に、排ガス中Ｃｏ／ＣＯ２＋ＣＯと火点
面積／浴衣面積の相関々係を明らかにしたが、本発明に
おいては、精錬用酸素ガスの火点面！／浴浴面面積比を
、０４以上にすることによって、充分なＣＯ２燃焼を期
待出来ることが判った。The present inventor has previously described a method for carburizing, melting and refining hot metal (patent application filed in 1983).
-231232) and clarified the correlation between Co/CO2+CO in exhaust gas and hot metal bath area/yukata area for each hot metal bath depth L)/hot metal bath diameter (D), but in the present invention, , the flash point of oxygen gas for refining! It was found that sufficient CO2 combustion can be expected by setting the /bath surface area ratio to 04 or more.

第７図にこの図衣を示す。Figure 7 shows this costume.

前述して来た様に本発明の特徴は、炭素源を溶銑表層上
部で燃焼させないで、一度溶鉄中に溶解させた後、Ｎ錬
用酸素で脱炭反応をさせ、その時光生ずるＣＯガスをさ
らにＣ０２まで燃焼させ熱効率を向上させる点に％徴が
ある。As mentioned above, the feature of the present invention is that the carbon source is not combusted in the upper surface layer of the molten metal, but is once dissolved in the molten iron, and then subjected to a decarburization reaction with N-smelting oxygen, and the CO gas produced at that time is removed. Furthermore, it is notable that it burns up to CO2 and improves thermal efficiency.

よって当然−鉄中に加炭している時期に、溶鉄中炭素製
置が比相溶解度以上になると、吹き込まれる炭素源は溶
鉄中に溶解することなく、スラグ層等の溶鉄面上部で燃
焼することとなり熱効率が低下する。よって、加炭祠錬
中の精錬用酸素ガス（Ｎｉ／　Ｆｉｒ　）　／炭素添加
速度（Ｋｙ／　Ｈｒ　）　〉１．　Ｏが望ましい。Therefore, it is natural that during carburization of iron, if the carbon in the molten iron exceeds the relative phase solubility, the injected carbon source will not dissolve in the molten iron, but will burn in the upper part of the molten iron surface, such as in the slag layer. As a result, thermal efficiency decreases. Therefore, the refining oxygen gas (Ni/Fir)/carbon addition rate (Ky/Hr) during carburization>1. O is desirable.

又前述した休に、スラグは少ない程、溶銑内に１ン（き
込まれる炭素源は効率良（加炭されるので、；ｌＩｉ疎
前の溶銃に、あらかじめ脱砂処理を施し、結球容器内で
のスラグ発生を、７０Ｋｇ／を以下に押えることは、極
めて効果的な方法である。In addition, as mentioned above, the less slag is injected into the hot metal, the more efficient the carbon source (because it is carburized); It is an extremely effective method to suppress the generation of slag within 70 kg/or less.

又この脱砂処理は、祠銖炉以外の所で実施することも出
来るが、精錬を中断してＮ錬炉で発生したスラグを排滓
する事によっても可能である。Further, this desanding treatment can be carried out at a place other than the slag furnace, but it is also possible by interrupting the smelting and discharging the slag generated in the N smelting furnace.

当然スラグ量を低下する手段として、脱砂処理だけにと
どまらず、脱燐、脱蝋処理まで実施すれば、さらに効率
が同上する事は言を待たない。Of course, as a means of reducing the amount of slag, it goes without saying that the efficiency will be further improved if not only desanding treatment but also dephosphorization and dewaxing treatment are carried out.

又酸素の火点面積率を向上させる手段として、２次燃焼
促進ランスがある。第８図はそのランスの部分図と投影
浴面積の模式図を示し、第９図は第８図の端面を示す模
式図である。A secondary combustion promotion lance is also available as a means for improving the oxygen flash point area ratio. FIG. 8 shows a partial view of the lance and a schematic diagram of the area of the projection bath, and FIG. 9 is a schematic diagram showing the end face of FIG.

図において炭素供給系として炭素源吹込孔１０と、その
外周近傍の鎖１鍍素供給系１１（以下主孔という）及び
炭素供給系から距離ｔをもつ第２酸素供給系１２（以下
副孔という）を所望数設ける。第２酸素供給系は同一ラ
ンスに内設した例を示したが、必ずしもこれに限定され
ない。In the figure, the carbon supply system includes a carbon source blowing hole 10, a chain 1 carbon supply system 11 (hereinafter referred to as the main hole) near its outer periphery, and a second oxygen supply system 12 (hereinafter referred to as the subhole) located at a distance t from the carbon supply system. ) are provided in the desired number. Although an example has been shown in which the second oxygen supply system is installed inside the same lance, the second oxygen supply system is not necessarily limited to this.

実験によるとランス中央部より炭素源を吠ぎ込む場合に
は、主孔、副孔の酸系ガスを独立に制御出来る特徴をい
かし、少なくても炭素源伏込み中の主孔の酸素を極力低
下させ、副孔側の酸系を増大させる事によって、ランス
先端からの溶銑表面までの間での炭素源の燃焼を防止し
、効率的に炭素源を添加出来る事が判った。Experiments have shown that when injecting a carbon source from the center of the lance, the ability to independently control the acid gas in the main and sub-pores is utilized to minimize the amount of oxygen in the main pore during the carbon source insertion. It was found that by reducing the amount of carbon and increasing the acid system on the sub-hole side, combustion of the carbon source between the tip of the lance and the surface of the hot metal can be prevented and the carbon source can be added efficiently.

その試験結果を第１０図に示すが、 なお炉壁煉瓦の居損を考属すると、１．０−３．０　Ｍ
、１氾囲が好まし℃・。図は無煙炭（ｌ　ｆｆｄｉｌ　
４　Ｑチ、１−・・＋ｊｉｌ　６０％を使用した例を示
した。The test results are shown in Figure 10, and if the loss of the furnace wall bricks is taken into account, it is 1.0-3.0 M.
, 1°C is preferred. The figure shows anthracite (l ffdil)
An example using 4 Qchi, 1-...+jil 60% was shown.

゛実施例１ ２００　ｔ　ｉ複合棺銑炉において、浴銑（Ｃ４，，２
％、ＳｉＯ，５％、Ｍｎ０．５％、ＰＯ，１％、８０．
０２％）１２０ｔとスクラップ８０ｔを装入し、無煙炭
（ＦｉｘＣ８５％）サイズｌ　ｍｎ　ｌ　Ｑ　＋１ｌＩ
Ｉｌ　’ｉｊ’４囲８０％ｃもの乞、）１・有涙用酸紫
ガス用ランスの中央部より、ストレートノズルで、火点
面と交叉しない様Ｎ２カスで吠込んだ。゛Example 1 In a 200 ti composite coffin pig furnace, bath pig iron (C4, 2
%, SiO, 5%, Mn0.5%, PO, 1%, 80.
02%) 120t and 80t of scrap were charged, and anthracite (FixC85%) size l mn l Q +1lI
1. From the center of the lacrimal acid purple gas lance, use a straight nozzle to inject N2 scum so as not to intersect the flash point surface.

無煙炭の吹込みは、０□吹吹回開始後２に開始し、１０
分で終り、０２吠課は２０分で吹止めた。The injection of anthracite started at 0□2 after the start of the blowing cycle, and at 10
It was over in 20 minutes, and the 2nd division was able to stop blowing in 20 minutes.

、１・１Ｊ諌用１ン２素ガスは４００００１’Ｊｆｆｉ
／　ｋｉｒであつｔコ。, 1N gas for 1.1J is 400001'Jffi
/ Kir de Atsutko.

帰；煙炭吹き込み速度は５００　Ｋｇ／分（２０にり／
ｌ→久）；ｉｉ’を疎用酸素ガスηＸ／　Ｈｒ　／炭系
吹込速度Ｋｙ／Ｈｒを１５、：ｉ’Ｆｆ錬離糸ガス火点
面積率０．７を維持した。Return: Charcoal blowing speed is 500 Kg/min (20 kg/min)
l→Ku); ii' was used sparingly, oxygen gas ηX/Hr/charcoal system blowing rate Ky/Hr was 15, and :i'Ff was maintained at a firing point area ratio of 0.7.

ｌｚ止酸成分Ｔｅｍｐ　１６５０℃、０２０８％、５ｉ
＝ｔ）、０１、胤二０．１５、Ｐ＝０．０２０．　Ｓ　
＝　０．０２０の軟銅を、屑鉄配合率４０％と言う高い
レベルで達成することか出来た。lz acid stopper component Temp 1650℃, 0208%, 5i
=t), 01, Taneji 0.15, P=0.020. S
= 0.020 annealed copper with a high scrap iron content of 40%.

実施例２ 混銑車にスケールをインジェクションして、脱砂処理を
施した。溶ｋ　（Ｓｉ　０．１５％、Ｍｎ　０．１５　
％Ｐ０．１０％、３０．０３％）を２ｏｏｔ′ｇ合精錬
炉に、１４０ｔとスクラップ６０ｔを装入し、コークス
粉を成形し、１　ｒｍｎ　−６ｔｚｎｚ囲に７５％入る
ものを、精錬用酸素ランスの中央部よりＮ２ガスにて、
火点面と交叉しない様吠き込んだ。Example 2 Scale was injected into a pig iron mixer car to perform sand removal treatment. Molten k (Si 0.15%, Mn 0.15
%P0.10%, 30.03%) was charged into a 2oot'g refining furnace, 140 tons and 60 tons of scrap were charged, and coke powder was formed. With N2 gas from the center of the lance,
I yelled so as not to cross the ignition surface.

尚この操業においては、精錬用１ｖ紫ノズルとして主孔
の他に、主孔の外側に副孔をもうけ、炉内での二次燃焼
（ＣＯ→Ｃ０２）を推進した。In this operation, in addition to the main hole, a sub-hole was provided outside the main hole as a 1V violet nozzle for refining to promote secondary combustion (CO→C02) in the furnace.

原形コークス粉の吹込みは、０２吹疎開始から３分後に
始め、８分に終り、０２吹殊は１８分で吹止めた。The blowing of the original coke powder started 3 minutes after the start of the 02 blowout and ended in 8 minutes, and the blowing of the 02 blowout was stopped in 18 minutes.

頴錬用酸素ガスは（主孔より２．５００　Ｏｎｔ／　Ｈ
ｒ副孔より１５０００ｍ’／Ｈｒ　）であった。Oxygen gas for tempering (2.500 Ont/H from the main hole)
15,000 m'/Hr from the r subhole).

コークス粉成形品伏込迎度は４ｏＯＫｒ／分（１０Ｋｇ
／を一装入） 精錬用酸素ガスｍｌ／Ｈｒ／炭素吹込速度に９／′Ｈｒ
を１７、精錬用酸素ガス火点面積系を０．８５、主孔酸
素供給速度／副孔酸系供給速度を全期間１．６に維持し
た。Coke powder molded product sinking rate is 4oOKr/min (10Kg
/ one charge) Refining oxygen gas ml/Hr/carbon injection rate 9/'Hr
was maintained at 17, the refining oxygen gas firing point area system was maintained at 0.85, and the main hole oxygen supply rate/subhole acid system supply rate was maintained at 1.6 throughout the period.

１次市成分、Ｔｅｍｐ１６３０℃、Ｃ０２０％、Ｓｉ　
０．０１係、ＩＶｆｎ　０１１０％、Ｐ　Ｏ，０１５％
、Ｓｏ、０１５％の中炭素鋼を、屑鉄配合率３０％と言
う高いレベルで１°、）る事が出来た。Primary city component, Temp1630℃, CO20%, Si
0.01 section, IVfn 0110%, P O, 015%
, So, 015% medium carbon steel was able to be heated by 1°) at a high level of scrap iron content of 30%.

実力用例３ ２００　を複合荀錬炉において、溶銑（Ｃ４，５％、Ｓ
ｉ　１．５　％、１ＶＩｎＯ，６％、Ｐｏ、１５％、８
０．０３０％）１００を装入し、散索カスを２分間（３
５０００フイ／Ｈｒ）供給し、脱Ｓ１反応をさせた後、
精錬を中断し、炉内の脱Ｓｉスラグを排滓截で昨去した
後、スクラップを１００　を装入し、褐炭（ＦｉｘＣ，
８０饅）サイズ１）囮−１０＋脂の範囲９０％のものを
、二次燃焼用ランスの中央部から、火点面積と交叉しな
い様にＮ２ガスで吹込んだ。Practical use example 3 200 ml of hot metal (C4.5%, S
i 1.5%, 1VInO, 6%, Po, 15%, 8
0.030%) 100 and soaked for 2 minutes (3
After supplying (5000 ft/Hr) and carrying out S1 removal reaction,
After stopping the refining and removing the Si-free slag in the furnace, 100% of scrap was charged and lignite (FixC,
80 rice cakes) Size 1) Decoy - 10 + Fat range 90% was blown in with N2 gas from the center of the secondary combustion lance so as not to cross the flame spot area.

褐炭の吹込みは、０２吹錬開始後５分に始め、２０分に
終り、０２吠錬は３０分で吹止めた。Injection of lignite started 5 minutes after the start of the 02 blowing process and ended in 20 minutes, and the blowing of the 02 blow process was stopped in 30 minutes.

１銖用酸素ガス：褐炭吹込み中（主孔２００００赫任）
それ以外期間（主孔３５，０００シ皆 副孔１５，００　（ｂｎ３／Ｈｒ） 褐炭吹き込速度：４００Ｋｙ／分（３０Ｋ９／　’ｔ−
装入）精錬用酸素ガス／炭素吹込速度−２０ 精錬用酸素ガス火点面積率−０，７５ 吹止成分で、Ｔｅｍｐ　１６５０℃、ＣＯＯ１０５φ、
Ｓ１０．０１％、胤：Ｏ，ＯＳ％、Ｐ：０．０２０％、
Ｓ：０．０２５％の低炭素鋼を屑鉄配合率５０％と言う
高いレベルで得る事が出来た。Oxygen gas for 1 bolt: During lignite injection (main hole 20,000 holes)
Other periods (35,000 main holes, 15,00 secondary holes (bn3/Hr) Lignite injection rate: 400Ky/min (30K9/'t-
Charge) Refining oxygen gas/carbon injection rate -20 Refining oxygen gas hot spot area ratio -0.75 With blow-off component, Temp 1650°C, COO105φ,
S10.01%, Seed: O, OS%, P: 0.020%,
S:0.025% low carbon steel could be obtained at a high level of scrap iron content of 50%.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は交叉面積率とスクラップ溶解能力の図表、第２
図は浴面投影面積の模式図、第３図は浴面とスクラップ
溶解能力の図表、第４図は浴面投影面積の模式図、第５
図はランスと投影面相の恨式図、第６図は炭素粒径とス
クラップ溶解能力の図表、第７図は排ガスと火点面積比
の図表、第８図はノズルと投影面積との模式図、第９図
はランス端面の模式図、第１０図はランス或素友とスク
ラツ第　１　図 第２　闇 第３図 第４図 θつ 第５図ど ７へ 炭尭才立／ｍｍ以千の倉屓１ 灯限Ｖ浴敦面積 第８　図 ｒｔ−３ 第１０図 主…畳＠す夕囁１１□、厭Ｎ努→Figure 1 is a diagram of the cross area ratio and scrap melting capacity, Figure 2
The figure is a schematic diagram of the projected area of the bath surface, Figure 3 is a diagram of the bath surface and scrap melting capacity, Figure 4 is a schematic diagram of the projected area of the bath surface, and Figure 5 is a diagram of the projected area of the bath surface.
Figure 6 is a diagram of the lance and projected surface phase, Figure 6 is a diagram of carbon particle size and scrap melting ability, Figure 7 is a diagram of exhaust gas and spark spot area ratio, and Figure 8 is a schematic diagram of the nozzle and projected area. , Fig. 9 is a schematic diagram of the end face of the lance, Fig. 10 is a schematic diagram of the lance end face, and Fig. 10 shows the lance. Kurama 1 Lamp limit V bath Atsushi area 8 Figure rt-3 Figure 10 Main...Tatami @Suyusa 11□, Tsunami N Tsutomu →

Claims (1)

【特許請求の範囲】 １　容器下部からガス発生物質を吹き込み、上方から酸
素カスを吹製し、溶鉄面上方からランスにより炭素含有
物質を溶鉄面に吹き込む複合梢課法において、炭素含有
物質の粒径がＩ　ｎ１１１１−Ｉ　Ｑ　ｊｊｕｎの範囲
のものを少くとも７０％以上占める炭素源を、梢錬酸素
ジェットの火点面と３０係以−ヒ交叉しない領域に、ラ
ンス中央部より溶鉄中央部表面に吹き込み、かつ加炭期
間及び脱炭期間は、精錬酸素カス火点面積（ｎＸ　）／
浴表面償（ｍ”）　＞　０．４に維持することを特徴と
する溶鉄加炭溶解精錬法。 ２　予め溶銑を脱硫、脱燐、脱硫処理して、精練容器内
に発生するスラグな７０４／ｌ−ｓ以下に制御する特許
請求の範囲第１項記載の溶鉄加炭３　炭素含有物質添加
前に精錬を中断して容器内スラグを排滓し、精錬容器内
で発生するスラグを７０Ｋｇ／ｌ−ｓ以下に制御する特
許請求の範囲第１項記載の溶鉄加炭溶解精錬法。 ４　加炭精錬の期間中、精錬酸素ガス（Ｎも）／炭素含
有物添加速度（ＫＶｈ）〉１０に維持する特許請求の範
囲第１項記載の溶鉄加炭溶解精錬１去。 ５　加炭精錬の炭素源吹込み期間中、炭素供給系の外周
近傍に設ける酸素供給系の酸素供比箪（ｃｔｎ′／ｈ　
）　／炭素供給系から距離ｔをもつ酸素供給系の酸素供
給量（ｃｒｔ？／　ｈ　）　＜　３．０に維持する特許
請求の範囲第１項記載の溶鉄加炭溶解精錬法。[Scope of Claims] 1. In a composite spraying method in which a gas-generating substance is blown from the bottom of the container, oxygen scum is blown from above, and a carbon-containing substance is blown onto the molten iron surface using a lance from above the molten iron surface, particles of the carbon-containing substance are A carbon source with a diameter in the range of I n1111-I Q jjun that accounts for at least 70% of the carbon source is placed in an area that does not intersect the firing point of the oxygen jet for more than 30 minutes, from the center of the lance to the surface of the center of the molten iron. and during the carburization period and decarburization period, the refining oxygen sludge firing point area (nX)/
A molten iron carburization melting and refining method characterized by maintaining bath surface reparation (m") > 0.4. 2. Hot metal is desulfurized, dephosphorized, and desulfurized in advance to eliminate slag generated in the scouring vessel. Molten iron carburization 3 according to claim 1, in which the slag generated in the smelting container is controlled to 70 Kg/l by interrupting the smelting process and draining the slag in the container before adding the carbon-containing substance. The molten iron carburizing melting and refining method according to claim 1, wherein the molten iron carburization melting and refining method is controlled to be less than or equal to -s.4 During the carburizing and refining period, the refining oxygen gas (N also)/carbon-containing material addition rate (KVh) is maintained at 10. 5. During the carbon source injection period of carburization and refining, the oxygen supply system (ctn'/ h
2. The molten iron carburization melting and refining method according to claim 1, wherein the oxygen supply amount (crt?/h) of the oxygen supply system having a distance t from the carbon supply system is maintained at <3.0.