JPS62103310A - Treatment for reforming refined slag - Google Patents

Abstract

PURPOSE:To make a treatment for reforming granular refined slag with high efficiency at a low cost by bringing gaseous oxygen flow into collision against gaseous flow carrying the refined slag and granular carbon material to generate to high-temp. flame. CONSTITUTION:Pulverized converter slag and carbon powder are conveyed in piping 11, 12 carrier gaseous flow and are joined in a confluent pipe 12. The joined powder is supplied to a injection nozzle 1. On the other hand, the gaseous oxygen flow is supplied by a gaseous oxygen supply pipe 7 to the nozzle 1. The converter slag, the gaseous flow contg. carbon and the gaseous oxygen flow are brought into collision against each other by the nozzle 1 to generate the high-temp. flame. The converter slag is heated and melted in the flame and the molten slag is conducted to a reaction vessel 2. The angle between both gaseous flows is made about >=20 deg.. A molten slag bath 3 formed in the above-mentioned is progressed in reduction and is easily reformed. Such slag is advantageously recycled.

Description

【発明の詳細な説明】 （産業上の利用分野） 転炉滓ないしは溶銑脱りん滓など、鉄冶金操業で生成し
た精錬滓より、その精錬原生に高濃度に含有され、焼結
用原料としては、転炉滓又は溶銑脱りん滓そのままのリ
サイクルの場合に不利な影響を与えていた、原生成分の
分離除去を、高い効率の下に安価なコストで成就するの
に有用な、精錬滓の変性処理に係わる開発研究の成果に
ついて以下述べる。[Detailed Description of the Invention] (Industrial Application Field) It is contained in high concentrations in the smelting raw material of smelting slag produced in iron metallurgy operations, such as converter slag or hot metal dephosphorization slag, and is used as a raw material for sintering. , a modification of smelting slag that is useful for accomplishing the separation and removal of raw materials with high efficiency and at low cost, which had a disadvantageous effect when recycling converter slag or hot metal dephosphorization slag as it is. The results of development research related to processing are described below.

製鋼スラグ、なかでも転炉滓は通常１〜４ｗｔ％のＰ２
Ｏ５を含有するが、鉄分く以下、Ｆｅで示す）を１０〜
３Ｑｗｔ％も含有し、さらにＣａｎを４０〜６０ｗｔ％
で含有することから、その一部を焼結工場へ戻し、焼結
鉱原料として、リサイクル利用することが望ましい。Steelmaking slag, especially converter slag, usually contains 1 to 4 wt% P2.
Contains O5, but the iron content (hereinafter referred to as Fe) is 10~
It also contains 3Qwt% and further contains 40-60wt% of Can.
Therefore, it is desirable to return some of it to the sintering factory and recycle it as a raw material for sintered ore.

しかし、このようなリサイクルによって高炉から出銑さ
れる溶銑中のりん濃度が高くなり、その結果製鋼過程で
脱りんのために造滓剤（Ｃａｎなど）の過剰使用が余儀
な（されて生成スラグが増加するような悪循環の原因と
なるため上記利用が妨げられていた。However, such recycling increases the phosphorus concentration in the hot metal tapped from the blast furnace, and as a result, excessive use of slag-forming agents (such as Can) for dephosphorization during the steelmaking process is forced (and the resulting slag The above usage has been hindered because it causes a vicious cycle in which

（従来の技術） 製鋼スラグ中のＰ２Ｏ５を除去する方法が種々に考えら
れ、たとえば特開昭５８〜１１０６１１号公報はその代
表例である。(Prior Art) Various methods for removing P2O5 from steelmaking slag have been considered, and for example, Japanese Patent Application Laid-Open No. 110611/1983 is a representative example.

すなわち、電気的加熱手段をそなえかつ底吹き羽口を有
する溶湯容器内に湛えた高温加熱溶銑の浴中に、キャリ
ヤガスでもって粉砕した転炉滓を、炭素を含む粉および
、スラグの流動性を良くする性質のある螢石、ボーキサ
イト、蛇紋石や電気炉滓などの媒溶剤と共に吹きこみ、
キャリヤガスのバブリング作用による溶銑浴の攪拌下に
、粉砕した転炉滓に固体酸素源を加えて吹込み、溶銑浴
中における有価元素につき、ソーダ系スラグとして回収
を図る方法である。That is, in a bath of high-temperature heated hot metal contained in a molten metal vessel equipped with an electric heating means and a bottom blowing tuyere, converter slag pulverized with a carrier gas is mixed with carbon-containing powder and the fluidity of slag. Injected with solvents such as fluorite, bauxite, serpentine, and electric furnace slag, which have properties that improve the
This is a method in which a solid oxygen source is added and blown into the crushed converter slag while the hot metal bath is stirred by the bubbling action of a carrier gas, and the valuable elements in the hot metal bath are recovered as soda-based slag.

しかしこの場合転炉滓中の有価元素を還元除去するのに
必要な溶銑加熱のための熱源として高価な電気エネルギ
ーを用いているため転炉滓の処理コストが嵩み経済的で
ないところに問題点を残している。However, in this case, the problem is that expensive electrical energy is used as a heat source for heating the hot metal necessary to reduce and remove the valuable elements in the converter slag, which increases the cost of processing the converter slag and makes it uneconomical. is left behind.

そこで、発明者らは先に、特願昭５９−２６８５１９号
にて精錬滓の改質方法を提案した。Therefore, the inventors previously proposed a method for reforming slag in Japanese Patent Application No. 59-268519.

すなわち容器内にあらかじめ湛えた高温溶銑中に向けて
、炭素含有物と予め粉砕した精錬滓とを搬送気流にのせ
て装入し、その噴射供給流を取囲む酸素ガスの噴流と衝
突させることにより精錬滓を系外へ逸散することなく高
温状態にして溶銑中に吹きこみ溶銑中の炭素により精錬
滓を脱りん改質する方法であり、高価な電気エネルギー
の代わりに安価な炭素含有物と酸素ガスとの燃焼エネル
ギーを用いて精錬滓を脱りん改質しようとするものであ
る。That is, by charging carbon-containing materials and pre-pulverized smelting slag onto a conveying air stream into high-temperature hot metal that has been prefilled in a container, and colliding with a jet of oxygen gas surrounding the injection supply stream. This is a method of dephosphorizing and reforming smelting slag by raising it to a high temperature and blowing it into hot metal without escaping it outside the system, and using the carbon in the hot metal to dephosphorize the smelting slag.It uses inexpensive carbon-containing material instead of expensive electrical energy. This is an attempt to dephosphorize and reform smelting slag using the energy of combustion with oxygen gas.

しかしながら、この方法では精錬滓を改質するのに高温
溶銑を用いるところに問題があった。つまり、高温溶銑
を用いているために高温溶銑自体の温度低下を防ぐため
の熱源を必要とし、精錬滓還元に必要とする炭素含有物
と酸素のエネルギーコストが本来の精錬滓還元に必要な
理論上のエネルギーをこえて必要になる。また、溶銑を
用いた際には精錬滓から還元したりんなどの元素は溶銑
中に含まれるため、溶銑は所定の回数の精錬滓の改質を
行った後、脱炭、脱りんを行い溶鋼にする必要があり、
このため精錬滓の改質プロセスは所定の回数毎に新しい
溶銑を要し、熱エネルギーコストおよび処理コストのい
ずれの上でも改良の余地を残す。However, this method has a problem in that high-temperature hot metal is used to reform the slag. In other words, since high-temperature hot metal is used, a heat source is required to prevent the temperature of the high-temperature hot metal itself from decreasing, and the energy cost of carbon-containing materials and oxygen required for smelting slag reduction is higher than the original theory necessary for smelting slag reduction. It is needed beyond the energy above. In addition, when hot metal is used, elements such as phosphorus reduced from the smelting slag are contained in the hot metal, so after reforming the smelting slag a predetermined number of times, the molten pig iron is decarburized and dephosphorized. need to be,
For this reason, the slag reforming process requires new hot metal every predetermined number of times, leaving room for improvement in terms of both thermal energy cost and processing cost.

（発明が解決しようとする問題点） 転炉滓や溶銑脱りん滓など冶金操業にて生成した洗練滓
から、その焼結鉱原料としてのリサイクル利用上不利な
元素を効果的かつ経済的に除去して精錬滓のより有利な
リサイクルを図るプロセスのコストをさらに下げ高効率
、低コストの精錬滓の改質プロセスにすることがこの発
明の目的である。(Problem to be solved by the invention) Effectively and economically removes elements that are disadvantageous for recycling as a raw material for sintered ore from refined slag generated in metallurgical operations such as converter slag and hot metal dephosphorization slag. It is an object of the present invention to further reduce the cost of the process for more advantageous recycling of the smelting slag, thereby making it a highly efficient and low-cost reforming process for the smelting slag.

（問題点を解決するための手段） この発明は転炉滓ないしは溶銑脱りん滓など鉄冶金操業
で生成した精錬滓の溶融物に対して、少なくとも炭素材
酸素を供給することを特徴とする精錬滓の改質処理方法
である。(Means for Solving the Problems) The present invention provides a smelting method characterized in that at least carbon material oxygen is supplied to a melt of smelting slag produced in iron metallurgy operations, such as converter slag or hot metal dephosphorization slag. This is a method for reforming slag.

精錬滓の溶融物が、 予め破砕して粉粒状とした精錬滓、 粉粒状炭素材の少なくとも一部、 の両者を別個に、あるいは混合して搬送気流にのせて供
給し、粉粒状炭素材を含む搬送気流に対して酸素気流を
衝突させて生じた高温火炎により、予め粉粒状とした精
錬滓を過熱昇温させて得られる溶融物であること、 炭素材の供給が、炭素材の少なくとも一部を粉粒状とな
して搬送気流にのせ、一方酸素の供給が、上記の搬送気
流に向けて衝突させること、さらには、 粉粒状炭素材の少なくとも一部と予め破砕して粉粒状と
した精錬源とを別個にあるいは混合して搬送気流にのせ
、この搬送気流に対して酸素気流を１重を突させること によって二層有利に上記の精錬源の改質処理方法が実現
される。The molten slag is supplied in advance by crushing the smelting slag into powder and at least a portion of the granular carbon material, either separately or in a mixed manner on a conveying air stream, to form the granular carbon material. The molten material is obtained by superheating and raising the temperature of smelting slag, which has previously been made into powder, using a high-temperature flame generated by colliding an oxygen stream with a carrier air stream containing the carbon material. The carbon material is pulverized into granules and placed on a conveying air stream, while the oxygen supply collides with the above-mentioned carrier air stream, and furthermore, at least a part of the granular carbon material is crushed in advance and refined into granules. The above-mentioned method for reforming the refining source can be realized in a two-layer advantageous manner by placing the oxygen gas separately or in a mixed manner on a carrier air stream, and by impinging a single oxygen stream on the carrier air stream.

第１図にてこの発明の実施要領を、模式に図解した。FIG. 1 schematically illustrates the implementation procedure of this invention.

図中１は噴射ノズル、２は反応容器、３は溶融スラグ、
４は噴射流、５は底吹きガス配管、６は冷却水配管、７
は酸素配管、８は炭素粉タンク、９は粉化精錬源タンク
であり、１０．１１　は搬送用窒素ガス配管、１２は合
流管である。In the figure, 1 is the injection nozzle, 2 is the reaction vessel, 3 is the molten slag,
4 is a jet flow, 5 is a bottom blowing gas pipe, 6 is a cooling water pipe, 7
8 is an oxygen pipe, 8 is a carbon powder tank, 9 is a powder refining source tank, 10.11 is a nitrogen gas pipe for transportation, and 12 is a merging pipe.

発明者らは、精錬源を粉化し、粉粒状炭素材および媒溶
剤とともに反応容器内へ搬送気流にのせて装入し、この
搬送流に対し酸素ガス気流の衝突を導くことにより該粉
粒状炭素材を燃焼させて高温火炎を該容器内で形成し、
この高温火炎中に粉化精錬源を通過させて溶湯容器内に
湛えた高温に溶銑の浴中に吹きこむ、上掲特願昭５９−
２６８５１９号の精錬源の改質方法に関し、試みに第１
図の装置を用いて反応容器に予め装入する高温溶銑量を
種々変化させ、精錬源の改質への溶銑の役割を調査した
。その結果、粉化した精錬源が溶解していれば、溶銑は
必ずしも必要ではないことが見出された。The inventors pulverized the smelting source, charged it into a reaction vessel along with a granular carbon material and a solvent, and introduced the collision of an oxygen gas stream against the granular carbon material into the granular coal. burning the material to form a high temperature flame within the container;
The above-mentioned patent application No. 59-197--in which a pulverized refining source is passed through this high-temperature flame and the high temperature in the molten metal container is blown into the hot metal bath.
Regarding the method of reforming the refining source of No. 268519, the first attempt was made.
Using the equipment shown in the figure, we varied the amount of high-temperature hot metal charged into the reaction vessel in advance to investigate the role of hot metal in reforming the refining source. As a result, it was found that hot metal is not necessarily necessary as long as the powdered refining source is molten.

第２図のａ）　、　ｂ）に噴射ノズルの噴口部を示した
ように、噴射ノズル１３又は１３′からそれぞれ粉化精
錬源と炭素粉、また噴気ノズル１４．１４’より酸素を
それらの衝突下に炭素粉の燃焼を導きつつ、粉化精錬源
を高温溶銑中に吹きこみ、その際高温溶銑量、粉化精錬
源および炭素粉の吹きこみ量を変化させて精錬源の還元
状況を調査した。その結果、高温溶銑は精錬源の還元に
おいて次の役割を果たしていることが判明した。As shown in Figure 2 a) and b), the injection nozzle 13 or 13' injects the pulverized smelting source and carbon powder, and the jet nozzles 14 and 14' inject oxygen into their collision. A pulverized smelting source is injected into high-temperature hot metal while guiding the combustion of carbon powder, and the reduction status of the smelting source is investigated by changing the amount of high-temperature molten metal, the amount of pulverized smelting source, and the amount of carbon powder blown into the molten pig iron. did. As a result, it was found that high-temperature hot metal plays the following roles in the reduction of smelting sources.

１）　精錬源を完全に溶解すること。1) Completely dissolve the refining source.

２）　溶銑中のＣが還元に寄与すること。2) C in hot metal contributes to reduction.

しかしながら、第２図に示したランスを用いる損業実験
にて、粉化精錬源は、溶銑中に吹きこまれる前、酸素ガ
スの気流が作る火炎中を通過する間にすでにほとんど溶
解し、高温溶銑はこの場合精錬滓を溶解するのに必要で
はなく、また粉化精錬源の還元についても同時に添加す
る固体炭素源によってほとんど還元が行われているため
溶銑中のＣは還元には事実上必要ではないことが判明し
た。However, in a commercial experiment using the lance shown in Figure 2, the pulverized smelting source was already almost melted while passing through the flame created by the oxygen gas stream before being blown into the hot metal, resulting in a high temperature. In this case, hot metal is not necessary to melt the smelting slag, and most of the reduction of the powdered smelting source is done by the solid carbon source added at the same time, so C in the hot metal is actually necessary for reduction. It turns out not to be.

つまり、粉化した精錬源が溶解していれば溶銑は必ずし
も必要ではないわけである。In other words, if the powdered refining source is molten, hot metal is not necessarily necessary.

そこで、さらに扮化精錬滓を吹き込む際に溶解させるの
に適したランスの形状を調査した。精錬源および炭素粉
を搬送するガス気流に対し酸素ガス気流の衝突角度を変
化させて精錬源の溶解状況について実験を行い、調査し
たところ、搬送流と酸素ガス気流の角度が０度より大き
くなるにつれ、炭材と酸素ガスとの衝突により火炎は高
温となり、そのなす角度が２０度以上となると浴中の精
錬源は完全に溶解しその結果炭素による還元状況も最も
良好であることが見出された。Therefore, we further investigated the shape of the lance suitable for dissolving the slag when blowing into it. An experiment was conducted to investigate the dissolution state of the refining source by changing the collision angle of the oxygen gas flow with respect to the gas flow transporting the refining source and carbon powder, and it was found that the angle between the transport flow and the oxygen gas flow was larger than 0 degrees. It was discovered that when the flame becomes hot due to the collision between the carbonaceous material and the oxygen gas, and the angle formed by the flame becomes 20 degrees or more, the refining source in the bath is completely dissolved, and as a result, the state of reduction by carbon is the best. It was done.

以上の結果から精錬源および炭素粉を搬送するガス気流
に対して酸素ガス気流を衝突させて高温火炎を形成させ
火炎中に粉化精錬源を通過させて容器内に吹きこむだけ
でこの発明の目的に適合する。From the above results, the present invention can be achieved by simply colliding an oxygen gas stream with a gas stream carrying a refining source and carbon powder to form a high-temperature flame, passing the powdered refining source through the flame, and blowing it into a container. Fit for purpose.

また、改質すべき精錬源は必ずしもその全量を上記のラ
ンスから粉粒状で供給しないでも、高温の溶融状態のも
のを炉内に装入し、上記の様にして、炭素粉と酸素ガス
を供給するだけで、スラグを溶融状態に保持しつつ還元
処理ができる。In addition, even if the entire amount of the refining source to be reformed is not necessarily supplied in the form of powder from the above-mentioned lance, a high-temperature molten source is charged into the furnace, and carbon powder and oxygen gas are supplied as described above. By simply doing this, the reduction process can be carried out while keeping the slag in a molten state.

以上の知見を基に溶銑を用いずに炭素含有物と酸素ガス
の燃焼による安価な熱源を用いて、粉化転炉滓を反応容
器内にて高温雰囲気を通過するように噴射供給するか、
溶融精錬滓に炭素含有物と酸素ガスを供給して有効な炭
素還元を行わせ、高効率下にコスト的にも有利な転炉滓
から有価元素を回収し、転炉スラグを脱りん変成させる
方法を与えることができる。Based on the above knowledge, it is possible to inject and supply powdered converter slag so that it passes through a high-temperature atmosphere in a reaction vessel, using an inexpensive heat source by combustion of carbon-containing materials and oxygen gas without using hot metal.
Supply carbon-containing substances and oxygen gas to the smelting slag to perform effective carbon reduction, recover valuable elements from the converter slag with high efficiency and cost advantage, and dephosphorize the converter slag. I can give you a method.

ところで製鋼過程で発生するスラグ量は一般に溶鋼１ト
ン当り８０〜１２０　ｋｇと大量であり、製鋼スラグの
利用として埋立て用や一部は路盤材などにも使われてい
るが、大部分は廃棄されている。Incidentally, the amount of slag generated during the steelmaking process is generally large, at 80 to 120 kg per ton of molten steel, and although steelmaking slag is used in landfills and some is used as roadbed material, the majority is discarded. has been done.

すでに触れたとおり製鉄所内でのリサイクルっまり焼結
工場に戻して転炉滓中のＴ、ＦｅやＣａＯを有効利用す
ることも実施されているが、このリサイクルにより、転
炉滓中のりんが再び溶銑に移行し、従ってこれは過剰量
の石灰による製鋼過程での除去を要し、そこに発生する
スラグ量が更に増加するという悪循環のため、リサイク
ル使用量に限界があった。As mentioned above, recycling within the steelworks is also returned to the sintering factory to effectively utilize T, Fe, and CaO in the converter slag, but through this recycling, phosphorus in the converter slag is There was a limit to the amount that could be recycled because of the vicious cycle of transitioning back to hot metal, which therefore had to be removed during the steelmaking process with an excess amount of lime, and the amount of slag generated therein further increased.

そこで製鋼滓のリサイクル量を増加するためには該原生
のりん除去がどうしても必要である。Therefore, in order to increase the amount of steel slag recycled, it is absolutely necessary to remove the native phosphorus.

製鋼滓からの脱りん方法としては、固体炭素による還元
除去が最も簡単で経済的にも他の方法より（優れている
ことは周知であるが、この発明はこの還元膜りんをさら
に有効に行うことができる方法を開発したところに有用
性がある。As a method for dephosphorizing steel slag, it is well known that reduction removal using solid carbon is the simplest and economically superior to other methods, but this invention makes this reduced membrane phosphorus even more effective. The usefulness lies in the development of a method that can do this.

この発明では転炉滓に炭素含有物が混入した噴出流に、
酸素ガスを衝突させるようなランス構造により転炉を容
易に溶融状態にして溶融スラグに吹きこめる。In this invention, the jet stream mixed with carbon-containing substances in the converter slag is
The lance structure allows oxygen gas to collide with the converter to easily bring it into a molten state and blow it into the molten slag.

なお粉化転炉滓と炭素粉は予め混合することもできるが
粉化転炉滓の搬送速度を小さく抑えるなど、ノズル孔内
面摩耗の問題がなければ、必ずしも混合する必要はない
。The pulverized converter slag and carbon powder can be mixed in advance, but it is not necessary to do so unless the conveyance speed of the pulverized converter slag is kept low and there is no problem of internal wear of the nozzle hole.

また製鋼工場におけるように、精錬滓を溶融状態で入手
できる場合は、これをそのまま利用することができ、さ
らに、精錬滓の溶解に要する熱源が不要となってエネル
ギー的に有利となる。この場合は、粉化転炉滓の使用量
を減じることによりランスノズルなどの粉化転炉滓によ
る摩耗などのトラブルをなくすことができる。Further, if the slag is available in a molten state, as in a steel factory, it can be used as is, and furthermore, a heat source required for melting the slag is not required, which is advantageous in terms of energy. In this case, by reducing the amount of powdered converter slag used, troubles such as wear of the lance nozzle and the like due to powdered converter slag can be eliminated.

（作　用） 第１図に従い炭素粉すなわちコークス粉または石炭粉と
、粉化転炉滓は別々のタンクから気体搬送し、ランスの
入口直前で混合し、この際安全性を考慮して、この混合
粉を搬送する配管１０．１１．１２に対し酸素ガス配管
７はランス頂端までは別々の配管にし、第２図（ａ）、
ら）に例示したノズル１を用いて反応容器２内にて火炎
を発生させる。(Function) According to Figure 1, carbon powder (coke powder or coal powder) and powdered converter slag are transported in gas from separate tanks and mixed just before the inlet of the lance. The oxygen gas piping 7 is separate from the piping 10, 11, and 12 for conveying the mixed powder up to the top of the lance, as shown in Fig. 2(a).
A flame is generated in the reaction vessel 2 using the nozzle 1 exemplified in (2).

この火炎中で粉化転炉滓を加熱溶融させるか、あるいは
精錬過程で生成して溶融状態をそのまま反応容器２に導
いてもよい。The pulverized converter slag may be heated and melted in this flame, or it may be generated during the refining process and the molten state may be directly introduced into the reaction vessel 2.

ここに供給された炭素粉は、酸素ガスと反応して粉化転
炉滓を加熱すると同時に、熱量の一部は転炉滓の還元反
応による吸熱、排ガス顕熱や炉体放散として持ち去られ
る熱量を補償する。The carbon powder supplied here reacts with oxygen gas to heat the powdered converter slag, and at the same time, part of the heat is absorbed by the reduction reaction of the converter slag, and the heat is carried away as exhaust gas sensible heat and furnace body radiation. Compensate for.

供給される炭素粉は上記火炎中ですべてが燃焼されるわ
けではなく、未反応の炭素は溶融スラグ浴中に浸入し、
溶融スラグの還元に使用される。The supplied carbon powder is not all burned in the flame, and unreacted carbon enters the molten slag bath.
Used for reducing molten slag.

上記ランスより粉化転炉滓と炭素粉を噴射供給し、これ
に対して酸素ガス気流を衝突させて、この際炭素粉によ
って形成された火炎中に上記粉化転炉滓を通過させ、炉
内の高温溶銑浴中に吹きつける。The pulverized converter slag and carbon powder are injected and supplied from the lance, and an oxygen gas stream is collided with them, and the pulverized converter slag is passed through the flame formed by the carbon powder. Blow into the high temperature hot metal bath inside.

すでに述べた様にその際酸素ガス気流と精錬滓と炭素粉
の搬送流のなす角度を２０度以上になるよう衝突させれ
ば精錬滓をほぼ溶融状態で吹きつけることができ、また
一部の精錬滓は容器底部に到達するまでに炭素粉によっ
て還元される。As already mentioned, if the oxygen gas flow, the smelting slag, and the carbon powder carrier flow collide at an angle of 20 degrees or more, the smelting slag can be sprayed in an almost molten state, and some The slag is reduced by carbon powder before reaching the bottom of the vessel.

かくして上記粉体の供給を継続すると溶融スラグ浴が生
成される。Thus, by continuing to feed the powder, a molten slag bath is produced.

この際溶融スラグ浴は容器内スラグ浴に到達するまでに
一部火炎中で炭素によって還元され、さらに溶融スラグ
中に吹きこまれている炭素粉によって完全に還元される
。At this time, the molten slag bath is partially reduced by carbon in the flame before reaching the slag bath in the container, and is further completely reduced by the carbon powder blown into the molten slag.

このようにして溶融スラグの還元が進み、溶融スラグ中
の酸化鉄、りんなどは還元されて、溶融スラグ底部には
高濃度のりんを含む溶鉄が蓄積される。In this way, the reduction of the molten slag progresses, iron oxide, phosphorus, etc. in the molten slag are reduced, and molten iron containing a high concentration of phosphorus is accumulated at the bottom of the molten slag.

この高濃度のりんを含む溶鉄は通常精錬滓１ｔｏｎ当り
１５０〜３００　ｋｇ生成し、多量のＣを含むため、未
還元の粉化精錬滓が若しも混入したときでもそれを改質
するのに寄与することとなる。Molten iron containing a high concentration of phosphorus is normally produced in an amount of 150 to 300 kg per ton of smelting slag, and contains a large amount of C, so even if unreduced pulverized smelting slag is mixed in, it is difficult to reform it. This will make a contribution.

溶融スラグが容器内で所定量増加した時点て改質溶融ス
ラグを排滓する。When the molten slag increases to a predetermined amount within the container, the modified molten slag is discharged.

その後、上記の精錬滓の改質プロセスをくり返し行う。Thereafter, the above-described reforming process of the slag is repeated.

生成した改質溶融スラグは容器から排出した後焼結工場
に移送して、有利にリサイクル使用に供されうる。改質
溶融スラグの排滓を何回かくり返した後、高濃度のりん
を含む溶鉄量が増加してくると、転炉滓および固体炭素
源の吹きごみを中止して炉内の変成後のスラグを全量排
出した後、溶鉄を排除する。The produced modified molten slag can be discharged from the container and then transferred to a sintering plant where it can be advantageously recycled. After the reformed molten slag has been repeatedly discharged several times, when the amount of molten iron containing a high concentration of phosphorus increases, the blowing waste of the converter slag and solid carbon source is stopped and the molten iron after the metamorphosis inside the furnace is removed. After all the slag has been discharged, remove the molten iron.

生成した高濃度りんを含む溶鉄は例えば鉄りん合金とし
て利用できる。The produced molten iron containing high concentration of phosphorus can be used, for example, as an iron-phosphorus alloy.

また酸素ガスを少量の脱りんフラックスと共に吹きこみ
通常の転炉で行う脱炭、脱りん吹錬を行う。その結果溶
銑中Ｐは吹錬スラグ中に移行し、溶銑は脱炭、脱りんさ
れ、通常の溶鋼に精錬される。In addition, oxygen gas is blown in with a small amount of dephosphorization flux to perform decarburization and dephosphorization blowing, which are performed in a normal converter. As a result, the P in the hot metal is transferred to the blowing slag, and the hot metal is decarburized, dephosphorized, and refined into normal molten steel.

このように生成した精錬スラグと溶鋼は、それぞれ前者
は燐肥として、後者は溶鋼として利用できる。The refined slag and molten steel thus generated can be used as phosphorus fertilizer and as molten steel, respectively.

したがって、この発明によれば転炉スラグの還元処理後
に得られる改質溶融スラグを焼結原料としてリサイクル
し、一方還元回収されたＰ、Ｆｅなどの有価元素は鉄り
ん合金あるいは溶鋼と燐肥として利用できる。こうした
転炉滓の利用プロセスフローを第３図に示す。Therefore, according to the present invention, the modified molten slag obtained after reduction treatment of converter slag is recycled as a sintering raw material, while the reduced and recovered valuable elements such as P and Fe are used as iron phosphorus alloy or molten steel and phosphorous fertilizer. Available. Figure 3 shows the process flow for utilizing such converter slag.

なお炭素が上記のランスからの供給だけでは不足する場
合、その不足分は炉底羽口から吹きこんでもよいし、経
済的には多少劣るが、少量でもあるので炉口から塊状の
炭素含有物を投入して補なってもよい。スラグの還元反
応を効率よく生せしめるには、スラグの流動性を確保す
ることが重要であり、そのためには、媒溶剤を適宜、炉
口乃至はランスから供給するのが好適である。If the supply of carbon from the above-mentioned lance is insufficient, the shortage can be blown in from the tuyere at the bottom of the furnace, or, although it is somewhat less economical, since it is a small amount, the carbon-containing lumps can be injected from the furnace mouth. You may supplement by adding . In order to efficiently carry out the reduction reaction of the slag, it is important to ensure the fluidity of the slag, and for this purpose, it is preferable to supply the solvent from the furnace mouth or lance.

実施例１ 第１図に示した設備により第２図（ａ）の噴射ノズル１
を用いて、５トン規模の転炉で実験を行った。Example 1 The injection nozzle 1 shown in FIG. 2(a) was constructed using the equipment shown in FIG.
An experiment was conducted in a 5-ton scale converter using .

この発明の実施例を以下に示す。反応容器２の底部に内
径４　ｍｍφの単管羽口を４本取付け、外気底吹きガス
配管５から導いたＮ２ガスを合計量でｌＮｍ３／ｍｉｎ
の割合にて供給しつつ、反応容器２内へ転炉精錬終了直
後の溶融スラグ３を３ｔ、媒溶剤としては螢石を１２０
　ｋｇそれぞれ装入した。Examples of this invention are shown below. Four single tube tuyeres with an inner diameter of 4 mmφ were attached to the bottom of the reaction vessel 2, and a total amount of N2 gas led from the outside air bottom blowing gas pipe 5 was 1Nm3/min.
While supplying 3 tons of molten slag 3 immediately after converter refining into the reaction vessel 2 at a ratio of 120 tons of fluorite as a solvent,
kg each.

続いて、噴射ノズル１を下降し、酸素を１ＯＮｍ’／ｍ
ｉｎ　、コークス粉を１７ｋｇ／ｍｉｎの割合で供給し
つつ、約６０分間の還元処理を行った。なお、途中で炭
素過多になるところでコークス粉を減少し理論燃焼分供
給した。該処理後、約６００　ｋｇの高濃度のりんを含
む溶銑が転炉滓中の鉄、燐、マンガンなどの還元によっ
て溶融スラグ３の下部に生成された。Next, the injection nozzle 1 is lowered and oxygen is injected at 1ONm'/m.
Reduction treatment was performed for about 60 minutes while supplying coke powder at a rate of 17 kg/min. In addition, the amount of coke powder was reduced at a point where there was too much carbon, and the amount of theoretical combustion was supplied. After the treatment, about 600 kg of hot metal containing high concentration of phosphorus was produced in the lower part of the molten slag 3 by reduction of iron, phosphorus, manganese, etc. in the converter slag.

前記、還元処理前の精錬滓と処理後の変形滓の組成を表
１に示す。また、転炉滓の還元において生じた溶銑の組
成を表２に示す。Table 1 shows the compositions of the smelting slag before the reduction treatment and the deformed slag after the treatment. Furthermore, Table 2 shows the composition of hot metal produced in the reduction of converter slag.

■ 表２ 実施例２ 第１図に示した設備と、第２図ら）のランス４を用いて
、５トン規模の転炉で実験を行ったこの発明の実施例を
以下に示す。転炉５へ５トンの溶銑を装入し、通常の脱
炭吹錬を行った後、出鋼孔より溶鋼のみをすっかり排出
した。■Table 2 Example 2 An example of the present invention is shown below, in which an experiment was conducted in a 5-ton converter using the equipment shown in FIG. 1 and the lance 4 shown in FIG. 2, etc. After charging 5 tons of hot metal into the converter 5 and performing normal decarburization blowing, only the molten steel was completely discharged from the tapping hole.

排出した後転炉内に残った溶融状態のスラグは約１ｔで
あった。底吹きガスを０．５Ｎｍ３７ｍｉｎ流しなから
転炉を直立させた後、精錬滓噴射ノズルと酸素ノズルと
のなす角が２５°のランス１を下降させ、酸素を１５Ｎ
ｍ３７ｍｉｎ　、　：］−ランスを２５ｋｇ／ｍｉｎ、
媒溶剤として螢石を１．６　ｋｇ／ｍｉｎとして粉化転
炉滓を４０１ａｇ／ｍｉｎの割合で供給した。Approximately 1 ton of molten slag remained in the converter after being discharged. After the converter was placed upright while the bottom blowing gas was flowing at 0.5 Nm for 37 min, the lance 1, which had an angle of 25° between the slag injection nozzle and the oxygen nozzle, was lowered and oxygen was injected at 15 Nm.
m37min, :]-Lance 25kg/min,
Fluorite was used as a solvent at a rate of 1.6 kg/min, and powdered converter slag was supplied at a rate of 401 ag/min.

なお、途中で炭素過多になるところでコークス粉を減少
した。In addition, the amount of coke powder was reduced at a point where there was too much carbon.

転炉滓を溶解した後、改質溶融スラグとして容器内にた
まり、溶融状のスラグと合計３ｔになるまで処理を行っ
た。その際に転炉滓１を当り約２００ｋｇの、高濃度の
りんを含む溶銑が転炉滓中の鉄、りん、マンガンなどの
還元により溶融スラグ３の下部に生成された。この溶銑
は転炉滓の溶解と溶鉄中炭素による転炉滓の還元に寄与
する。After the converter slag was melted, it was collected in a container as modified molten slag, and the process was continued until the total amount including molten slag reached 3 tons. At that time, about 200 kg of hot metal containing high concentration of phosphorus per converter slag 1 was generated in the lower part of molten slag 3 by reduction of iron, phosphorus, manganese, etc. in the converter slag. This hot metal contributes to the melting of the converter slag and the reduction of the converter slag by the carbon in the molten iron.

還元処理前の洗練滓と処理後の改質溶融スラグの組成を
表３に示す。Table 3 shows the compositions of the refined slag before reduction treatment and the modified molten slag after treatment.

表３ （ｗｔ％） さらに転炉滓の還元において生じた溶鉄の組成を表４に
示す。Table 3 (wt%) Furthermore, Table 4 shows the composition of the molten iron produced in the reduction of the converter slag.

表４ 実施例３ 転炉底部には単管羽口を用いてＮ２またはＡｒガスを溶
鉄１を当りＯ，ＱＯ３〜Ｏ，１５Ｎｍ’／ｍｉｎ供給で
きるようにした。溶銑の装入されていない転炉の炉口か
ら続いて炭素材または／および精錬滓噴射ノズルと、酸
素ノズルとのなす角度が２５°のランス１を下降させ、
酸素を１５Ｎｍ３７ｍｉｎ　、：］　−ランスを２５ｋ
ｇ／ｍｉｎ、媒溶剤として螢石を１．６　ｋｇ／＋ｎｉ
ｎとして粉化転炉滓を４０ｋｇ／ｍｉｎの割合で供給し
た。Table 4 Example 3 A single tube tuyere was used at the bottom of the converter so that N2 or Ar gas could be supplied at a rate of O, QO3 to O, 15 Nm'/min per molten iron. Continuing from the furnace mouth of the converter where hot metal is not charged, the lance 1 having an angle of 25° between the carbon material or/and smelting slag injection nozzle and the oxygen nozzle is lowered,
Oxygen at 15Nm37min, :] - Lance at 25k
g/min, 1.6 kg/+ni of fluorite as a solvent
The powdered converter slag was supplied as n at a rate of 40 kg/min.

ここで媒溶剤は螢石の場合粉化転炉滓量の４％程度添加
した。In the case of fluorite, the solvent was added in an amount of about 4% of the amount of powdered converter slag.

なお、途中で炭素過多になるところでコークス粉を減少
し理論燃焼量分供給した。In addition, the amount of coke powder was reduced at a point where there was an excess of carbon, and the amount of coke powder was supplied in the amount equal to the theoretical combustion amount.

転炉滓は溶解した後変成スラグとして容器にたまり、計
３ｔになるまで上記処理を行った。After the converter slag was melted, it was collected in a container as metamorphosed slag, and the above treatment was carried out until the total amount was 3 tons.

その際に転炉滓１を当り約２００　ｋｇの高濃度のりん
を含む溶銑が転炉滓中の鉄、りん、マンガンなどの還元
によって溶融スラグ３の下部に生成された。この溶銑は
転炉滓の溶解と溶鉄中炭素による転炉滓の還元に寄与す
る。還元処理前の精錬滓と処理後の改質溶融スラグの組
成は実施例２とほぼ同じであった 以上の実施例１〜３ではコークスを用いたが微粉炭を固
体炭素源として用いても本質的には全く違いはない。た
だし微粉炭の場合にはそれに含有される炭化水素中の水
素が火炎中で酸化し発熱するが鉄浴面で再び還元される
ので、転炉全体の熱収支の観点からはコークス粉の場合
より発熱量が小さくなるので供給量を増加させればよい
。At this time, about 200 kg of hot metal containing high concentration of phosphorus per converter slag 1 was generated in the lower part of molten slag 3 by reduction of iron, phosphorus, manganese, etc. in the converter slag. This hot metal contributes to the melting of the converter slag and the reduction of the converter slag by the carbon in the molten iron. The compositions of the smelting slag before the reduction treatment and the modified molten slag after the treatment were almost the same as in Example 2. Although coke was used in Examples 1 to 3 above, it is essentially the same even if pulverized coal is used as the solid carbon source. There is no difference at all. However, in the case of pulverized coal, the hydrogen in the hydrocarbons contained in it oxidizes in the flame and generates heat, but it is reduced again on the iron bath surface, so from the perspective of the heat balance of the entire converter, it is better than the case of coke powder. Since the amount of heat generated is small, the supply amount can be increased.

また、これらの実施例では、熱収支を計算すると過剰に
炭素分を添加していることがわかるが、これは実験を行
った転炉が小さいため、単位メタル当りの炉体成敗熱が
大型炉に較べて大きく、この熱を補うための炭素分に見
合うことがわかった。In addition, in these examples, when calculating the heat balance, it is found that excessive carbon content was added, but this is because the converter in which the experiment was conducted was small, and the heat of failure of the furnace body per unit metal was higher than that of a large furnace. It was found that the carbon content was large compared to that of the previous year, and that it was worth the carbon content to compensate for this heat.

なお、これらの実施例では転炉滓の還元について主に説
明したが溶銑脱りん滓や近年注目されている転炉内での
Ｍｎ鉱石やＣｒ鉱石を溶融還元した後のスラグなど、炭
素で還元しうるスラグの改質ならば何でもこの発明の対
象となり得るのはいうまでもない。In addition, although these examples mainly explained the reduction of converter slag, hot metal dephosphorization slag and slag after melting and reducing Mn ore and Cr ore in the converter, which have been attracting attention in recent years, can also be reduced with carbon. Needless to say, any possible modification of slag can be covered by the present invention.

（発明の効果） 以上の結果から、電力などの高価なエネルギーの代わり
に数分の１のコストの下で微粉炭やコークス粉の酸素ガ
スとの燃焼エネルギーを用いて、通常２〜５％のＰ２Ｏ
５を含む製鋼滓からＰ２Ｏ５≦０．１０％の変成スラグ
が得られる。この結果、高炉へ製鋼滓のリサイクルを行
っても出銑りん濃度を事実上高める不利がなくなる。(Effects of the invention) From the above results, it has been found that by using the combustion energy of pulverized coal or coke powder with oxygen gas at a fraction of the cost instead of using expensive energy such as electricity, P2O
Metamorphic slag with P2O5≦0.10% can be obtained from steel slag containing P2O5. As a result, even if steel slag is recycled to the blast furnace, there is no disadvantage of effectively increasing the tap iron phosphorus concentration.

またこれらのスラグの改質に伴い、スラグ中の鉄やりん
は溶鉄、フェロリンとしてさらには燐肥などとして回収
利用できる。In addition, as these slags are reformed, iron and phosphorus in the slags can be recovered and used as molten iron, ferroline, and even phosphorus fertilizer.

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

第１図は実験を行った設備を示すスケルトン図、第２図
はこの発明の実施に用いたランス先端のノズル構成を例
示した断面図、 第３図はこの発明によるプロセスの流れ図である。 ■・・・噴射ノズル　　　　２・・・反応容器３・・・
溶融スラグ　　　　４・・・噴射流５・・・底吹きガス
配管　　６・・・冷却水配管７・・・酸素配管　　　　
　訃・・炭素粉タンク９・・・粉化精錬滓タンク １０．１１・・・搬送用窒素ガス配管 １２・・・合流管 １３、１３　’・・・転炉スラグ粉炭素粉の噴射ノズル
１４、１４　’・・・酸素ガス噴射ノズル１５・・・ラ
ンス水冷水路FIG. 1 is a skeleton diagram showing the equipment on which the experiment was conducted, FIG. 2 is a cross-sectional view illustrating the nozzle configuration at the tip of the lance used in carrying out the present invention, and FIG. 3 is a flowchart of the process according to the present invention. ■...Injection nozzle 2...Reaction vessel 3...
Molten slag 4... Jet flow 5... Bottom blowing gas piping 6... Cooling water piping 7... Oxygen piping
Death...Carbon powder tank 9...Powdered smelting slag tank 10.11...Nitrogen gas piping for transportation 12...Merge pipes 13, 13'...Converter slag powder carbon powder injection nozzle 14, 14'...Oxygen gas injection nozzle 15...Lance water cooling channel

Claims (1)

【特許請求の範囲】 １、転炉滓ないしは溶銑脱りん滓など鉄冶金操業で生成
した精錬滓の溶融物に対して、 炭素材を供給すると共に、酸素を供給する こと を特徴とする精錬滓の改質処理方法。 ２、精錬滓の溶融物が、 予め破砕して粉粒状とした精錬滓、 粉粒状炭素材の少なくとも一部、 の両者を別個に、あるいは混合して搬送気流にのせて供
給し、粉粒状炭素材を含む搬送気流に対して酸素気流を
衝突させて生じた高温火炎により、予め粉粒状とした精
錬滓を加熱昇温させて得られる溶融物である１記載の処
理方法。 ３、炭素材の供給が、炭素材の少なくとも一部を粉粒状
となして搬送気流にのせ、一方酸素の供給が、上記の搬
送気流に向けて衝突させる ことからなる、１、又は２、記載の処理方法。 ４、粉粒状炭素材の少なくとも一部と、予め破砕して粉
粒状とした精錬滓とを、別個にあるいは混合して搬送気
流にのせ、この搬送気流に対して酸素気流を衝突させる
ことからなる１〜３の何れか一に記載の処理方法。[Scope of Claims] 1. A smelting slag characterized by supplying carbon material and oxygen to a melt of smelting slag produced in iron metallurgy operations, such as converter slag or hot metal dephosphorization slag. Modification treatment method. 2. The molten material of the smelting slag is supplied by supplying the smelting slag, which has been crushed in advance into powder, and at least a part of the granular carbon material, either separately or in a mixed manner on a conveying air stream, to form granular charcoal. 1. The processing method according to 1, wherein the molten material is obtained by heating and raising the temperature of smelting slag, which has been previously made into powder, using a high-temperature flame generated by colliding an oxygen stream with a conveying air stream containing the raw material. 3. The description in 1 or 2, wherein the supply of the carbon material consists of making at least a part of the carbon material into powder and granules and placing it on the carrier air stream, while the supply of oxygen consists of colliding it toward the carrier air stream. processing method. 4. At least a part of the granular carbon material and the smelting slag, which has been crushed in advance and made into granules, are placed on a conveying air stream, either separately or in a mixture, and an oxygen air stream is made to collide with the conveying air stream. 4. The treatment method according to any one of 1 to 3.