JPH0765120B2 - Method and apparatus for refining molten metal by ultrasonic wave - Google Patents
Method and apparatus for refining molten metal by ultrasonic waveInfo
- Publication number
- JPH0765120B2 JPH0765120B2 JP62283138A JP28313887A JPH0765120B2 JP H0765120 B2 JPH0765120 B2 JP H0765120B2 JP 62283138 A JP62283138 A JP 62283138A JP 28313887 A JP28313887 A JP 28313887A JP H0765120 B2 JPH0765120 B2 JP H0765120B2
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- Prior art keywords
- gas
- refining
- molten steel
- molten metal
- nozzle
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Classifications
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- 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
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は精錬ガスに超音波を印加して精錬反応の迅速化
を図った、溶融金属の精錬方法およびその装置に関す
る。Description: TECHNICAL FIELD The present invention relates to a method for refining molten metal and an apparatus for refining molten metal by applying ultrasonic waves to a refining gas to accelerate the refining reaction.
溶融金属の精錬においては、通常、浴中に不活性なガス
あるいは活性なガスを吹込み、精錬反応を促進する方法
が多用されている。この際にはガス吹込みによる精錬反
応の促進効果を大とすることが必要である。In refining molten metal, a method of blowing an inert gas or an active gas into a bath to accelerate the refining reaction is often used. In this case, it is necessary to enhance the effect of promoting the refining reaction by blowing gas.
代表的な例の第１として、溶鋼の脱酸処理について説明
すると、この場合には、取鍋内の溶鋼中にアルミニウム
（Al）などの脱酸剤を添加し、溶鋼中に溶存している酸
素を微細な酸化物として析出させ、これらの微小析出物
例えばAl2O3を溶鋼から浮上分離させる。この際に、ア
ルゴンガスを吹込み浴を撹拌することによって、脱酸生
成物である酸化物の分離速度を促進する、いわゆるArガ
ス撹拌法がある。As a first representative example, the deoxidation treatment of molten steel will be described. In this case, a deoxidizing agent such as aluminum (Al) is added to the molten steel in the ladle and dissolved in the molten steel. Oxygen is precipitated as fine oxides, and these fine precipitates such as Al 2 O 3 are floated and separated from the molten steel. At this time, there is a so-called Ar gas stirring method in which argon gas is blown into the bath to stir to accelerate the separation rate of oxides that are deoxidized products.
この方法は非常に簡便な設備で、しかも処理費用も低額
であるため製鋼工程で多用されている。この際に、酸化
物の分離速度、すなわち脱酸速度を向上させることは、
精錬操作の能率向上の点でも、また酸化物の少ない清浄
な鋼を得る点でも非常に重要である。This method is widely used in the steelmaking process because it is a very simple facility and the processing cost is low. At this time, improving the separation rate of oxides, that is, the deoxidation rate,
It is very important in terms of improving the efficiency of refining operation and obtaining clean steel with less oxide.
脱酸速度を向上するために種々の方法が採用されてい
る。その１つの方法として、Arガスの吹込み羽口に多孔
質のレンガを用いて気泡を微細化し、多数の気泡を作っ
て気泡への酸化物の吸着を促進する方法がある。この方
法はArガス吹込み羽口としてノズルを用いる方法より気
泡が微細化される点で優れ、脱酸速度も大となる。Various methods have been adopted to improve the deoxidation rate. As one of the methods, there is a method in which a porous brick is used for the tuyere of blowing Ar gas to make bubbles fine, and a large number of bubbles are formed to promote adsorption of oxides to the bubbles. This method is superior to the method using a nozzle as the tuyere for blowing Ar gas in that the bubbles are made finer, and the deoxidation rate is also high.
しかし、真空脱ガス装置を用いる脱酸方法と比較する
と、到達可能な酸素濃度に限界があり、Arガス撹拌法は
高級鋼の製造には不十分である。However, compared with the deoxidizing method using a vacuum degassing device, there is a limit to the oxygen concentration that can be reached, and the Ar gas stirring method is insufficient for producing high-grade steel.
代表的な第２例として溶鋼中にArガスを吹込み溶鋼中に
溶解している水素や窒素を気泡中に移行させて除去す
る、いわゆる脱ガス処理がある。このような操作は多量
のArガスを使用すれば原理的には可能であるが脱ガス効
率が悪いために現在では工業的に使用されていない。As a typical second example, there is a so-called degassing treatment in which Ar gas is blown into molten steel to remove hydrogen and nitrogen dissolved in molten steel by moving them into bubbles. Such an operation is possible in principle if a large amount of Ar gas is used, but it is not industrially used at present due to poor degassing efficiency.
本発明は以上のような従来技術に改善を加えて精錬反応
の促進と効率化を図ることを目的とし、超音波を用いた
溶融金属の精錬方法を提供するものである。The present invention aims to promote the refining reaction and improve efficiency by improving the above-mentioned conventional techniques and to provide a method for refining molten metal using ultrasonic waves.
本発明方法は、溶鋼金属中にガスを吹込んで精錬を行う
に当り、ノズルまたは羽口に超音波を印加することを特
徴とする溶鋼金属の精錬方法である。The method of the present invention is a refining method for molten steel metal, which comprises applying ultrasonic waves to a nozzle or tuyere when blowing gas into the molten steel for refining.
上記本発明方法を好適に実施することのできる本発明装
置は、金属棒の一端に超音波振動子を装着し、該金属棒
中にガス通路を形成し、他端を溶融金属中にガスを吹込
むノズルまたは羽口を形成したことを特徴とする溶鋼金
属の精錬装置である。The apparatus of the present invention capable of suitably carrying out the method of the present invention is such that an ultrasonic transducer is attached to one end of a metal rod, a gas passage is formed in the metal rod, and a gas is introduced into the molten metal at the other end. A refining device for molten steel metal, characterized in that a blowing nozzle or tuyere is formed.
本発明はガス吹込み精錬における反応の促進を目的とし
て超音波を利用するものであり、その原理はガス気泡を
吹込むノズルに超音波を印加すると気泡が非常に微細化
されることによる。The present invention utilizes ultrasonic waves for the purpose of accelerating the reaction in the gas blowing refining, and the principle thereof is that when ultrasonic waves are applied to a nozzle for blowing gas bubbles, the bubbles are extremely miniaturized.
このように気泡が微細化されると溶鋼を気泡間の界面積
が増大することによって、第１の例の脱酸処理では酸化
物の気泡への吸着によって除去される脱酸速度が増大す
る。When the bubbles are miniaturized in this manner, the interfacial area between the molten steel and the bubbles is increased, so that in the deoxidation treatment of the first example, the deoxidation rate at which oxides are removed by adsorption to the bubbles is increased.
また、溶鋼中に溶解している窒素や水素を気泡によって
脱ガスする第２の場合においても、気泡と溶鋼中の界面
積が増大するために脱ガス速度が大となる。Also, in the second case in which nitrogen or hydrogen dissolved in the molten steel is degassed by the bubbles, the degassing rate becomes large because the boundary area between the bubbles and the molten steel increases.
次に本発明の装置は金属棒の一端に超音波振動子を装着
し、他端にノズルまたは羽口を形成したので、直接ノズ
ルまたは羽口に超音波が伝達され、効率よく精錬を行う
ことを可能とする。Next, in the device of the present invention, the ultrasonic transducer was attached to one end of the metal rod, and the nozzle or tuyere was formed at the other end, so that the ultrasonic wave is directly transmitted to the nozzle or tuyere to efficiently perform refining. Is possible.
第１図、第２図に本発明の実施例の概略を示すが、第１
図では超音波伝達用のホーンとしての金属棒１の周囲に
耐火材２を構築し、金属棒の中心部にArガス通路３を設
ける。このようにして金属棒１の先端部に超音波振動子
４を設置する。これを取鍋５の溶鋼６中に浸漬し、Arガ
ス通路３を通じてその先端のノズル７からArガスを溶鋼
中に吹込む。The outline of the embodiment of the present invention is shown in FIG. 1 and FIG.
In the figure, a refractory material 2 is built around a metal rod 1 as a horn for transmitting ultrasonic waves, and an Ar gas passage 3 is provided at the center of the metal rod. In this way, the ultrasonic transducer 4 is installed at the tip of the metal rod 1. This is immersed in the molten steel 6 in the ladle 5, and Ar gas is blown into the molten steel through the Ar gas passage 3 from the nozzle 7 at the tip.
また第２図の例では、取鍋５の底部に設けた金属パイプ
８、９からなる２重管ノズルにおいて、内管ノズルを形
成する金属パイプ８の先端に振動子４を設置し、内管８
に超音波を印加する、このようにして外管９と内管８の
作る環状部と内管８にA4rガスを流し、２重管ノズルの
先端部から浴中にArガスを吹込む。Further, in the example of FIG. 2, in the double pipe nozzle composed of the metal pipes 8 and 9 provided at the bottom of the ladle 5, the vibrator 4 is installed at the tip of the metal pipe 8 forming the inner pipe nozzle, 8
Ultrasonic waves are applied to the inner tube 8 and the annular portion formed by the outer tube 9 and the inner tube 8 in this manner, and Ar gas is blown into the bath from the tip of the double tube nozzle.
このような方法による超音波の気泡微細化効果につい
て、まず第１図に示す方法によって水中に窒素ガスを吹
込み、ノズル先端部で生成される気泡の直径を高速度写
真撮影によって測定した。Regarding the effect of ultrasonic bubble miniaturization by such a method, first, nitrogen gas was blown into water by the method shown in FIG. 1, and the diameter of the bubble generated at the tip of the nozzle was measured by high-speed photography.
この実験ではホーン部長さが118mmでノズルの先端の外
径は5mm、内径は2mmとし、ノズル先端からガス導入口ま
では74mmとして、ガス導入位置はホーンの振動の節の位
置とした。超音波発振器は周波数25kHz、出力100Wであ
る。内径が150mmで高さが250mmのアクリル製の円筒に約
３の水（水深165mm）を入れ、ノズル先端が浴面から7
5mm位置となるように浸漬し、N2ガスあるいはCO2ガスを
吹き込んだ。In this experiment, the horn length was 118 mm, the outer diameter of the nozzle tip was 5 mm, the inner diameter was 2 mm, the distance from the nozzle tip to the gas introduction port was 74 mm, and the gas introduction position was at the vibration node of the horn. The ultrasonic oscillator has a frequency of 25 kHz and an output of 100 W. Approximately 3 water (water depth of 165 mm) is put into an acrylic cylinder with an inner diameter of 150 mm and a height of 250 mm, and the nozzle tip is 7 from the bath surface.
It was immersed so that the position was 5 mm, and N 2 gas or CO 2 gas was blown into it.
ガス流量が0.5〜3.0N/minの範囲において、超音波を
印加する場合としない場合で、気泡径は大幅に異なり、
平均粒径で約10倍の差のあることが明らかとなった。ま
た、この傾向は小流量の場合ほぼ大きく、0.5N/minで
は12〜13倍の差があり、超音波を印加すると気泡径が著
しく微細化されることが明らかとなった。In the gas flow rate range of 0.5 to 3.0 N / min, the bubble diameter is significantly different depending on whether ultrasonic waves are applied or not.
It was revealed that there is a difference of about 10 times in the average particle size. In addition, this tendency is almost large when the flow rate is small, and there is a difference of 12 to 13 times at 0.5 N / min, and it was clarified that the bubble diameter was remarkably reduced when ultrasonic waves were applied.
さらに円筒内の水を0.02規定のNaOH溶液としてCO2ガス
あるいはN2ガスを吹込みCO2ガスの吸収速度、あるいはC
O2ガスの脱ガスについて、超音波印加の効果を調査し
た。水溶液中のCO2ガスの濃度変化は次式で表される。Further, the water in the cylinder is made into a 0.02N NaOH solution and CO 2 gas or N 2 gas is blown into it to absorb CO 2 gas or
Regarding the degassing of O 2 gas, the effect of ultrasonic wave application was investigated. The change in CO 2 gas concentration in the aqueous solution is expressed by the following equation.
ただし、 Ce:気液界面での液側のCO2濃度（％） Co:実験開始時のCO2濃度（％） C:時刻ｔにおけるCO2濃度（％） K:見掛けの速度定数（min-1） t:時間（min） である。上式における速度定数Ｋの値を測定して超音波
印加の効果を調べた。 However, Ce: CO 2 concentration in the liquid side in the gas-liquid interface (%) Co: CO 2 concentration at the beginning of the experiment (%) C: CO 2 concentration (%) at time t K: apparent rate constants (min - 1 ) t: time (min). The value of the rate constant K in the above equation was measured to examine the effect of ultrasonic wave application.
その結果、速度定数ＫはCO2の吸収および脱ガスの両実
験ともに超音波を印加すると、1.3〜３倍程度増大する
ことが明らかとなった。As a result, it was revealed that the rate constant K was increased by about 1.3 to 3 times when ultrasonic waves were applied in both CO 2 absorption and degassing experiments.
以上の実験結果に基づき、1kW、25kWHzの超音波発振器
を用いて、第１図に示す方法で約50kgの溶鋼を用いたア
ルミニウム脱酸実験を行い、Arガスを一定時間吹込み溶
鋼中の酸素濃度を測定し、次式に基づいてｋの値を求め
た。Based on the above experimental results, an aluminum deoxidation experiment was performed using about 50 kg of molten steel by the method shown in FIG. The concentration was measured and the value of k was calculated based on the following equation.
ただし、 Co:t＝ｏでの酸素濃度（ppm） Cf:t＝ｔｆでの酸素濃度（ppm） k:脱酸速度定数（min-1） ｔｆ:Arガス吹込み時間（min） である。この実験では溶鋼は炭素0.04〜0.06％を含有す
る鉄鉄・炭素２元系であり、酸素濃度は約500ppmであ
る。 However, Co: t = oxygen concentration (ppm) in o Cf: t = oxygen concentration at t f (ppm) k: an Ar gas blowing time (min): deoxidation rate constant (min -1) t f is there. In this experiment, the molten steel is a ferrous iron / carbon binary system containing 0.04 to 0.06% carbon, and the oxygen concentration is about 500 ppm.
吹込み装置を取鍋内の溶鋼中に約80mm浸漬して、Arガス
を3N/minで吹込むと共、約1kgのAlを添加し、脱酸処
理を行った。The blowing apparatus was immersed in molten steel in a ladle for about 80 mm, and Ar gas was blown at 3 N / min, about 1 kg of Al was added, and deoxidation treatment was performed.
実験開始時と５〜10分のArガス吹き後、溶鋼サンプルを
採取し、酸素濃度を分析して前式に基づいて脱酸速度定
数ｋを求めた。その結果、超音波を印加しない場合は、 ｋ＝0.05〜0.09 min-1 であり超音波を印加すると、 ｋ＝0.07〜0.14 min-1 となり、超音波印加によって脱酸速度定数は平均値で約
1.5倍大きくなることが明らかである。At the start of the experiment and after blowing Ar gas for 5 to 10 minutes, a molten steel sample was taken, the oxygen concentration was analyzed, and the deoxidation rate constant k was obtained based on the above equation. As a result, when ultrasonic wave was not applied, k = 0.05 to 0.09 min −1 , and when ultrasonic wave was applied, k = 0.07 to 0.14 min −1 , and the deoxidation rate constant was about an average value when ultrasonic wave was applied.
It is clear that it will be 1.5 times larger.
また、脱酸処理終了時の溶鋼の酸素濃度も超音波印加で
15〜23ppm、印加なしで21〜38ppmであり、超音波印加に
より酸素濃度が大幅に低下し、清浄な鋼の製造の可能な
ことが明らかとなった。Also, the oxygen concentration in the molten steel at the end of the deoxidizing treatment can be determined by applying ultrasonic waves.
It was 15 to 23 ppm and 21 to 38 ppm without application, and it became clear that the oxygen concentration was significantly reduced by the application of ultrasonic waves, and that it was possible to produce clean steel.
この結果は水溶液系の実験にて観察されたように、Arガ
ス気泡が超音波の印加によって微細化されるため、気泡
へのAl2O3の吸着が促進されるためと考えられる。This result is considered to be because, as observed in the experiment of the aqueous solution system, the Ar gas bubbles are miniaturized by the application of ultrasonic waves, so that the adsorption of Al 2 O 3 on the bubbles is promoted.
また、水溶液の実験では明らかではないが、その他の理
由として超音波がノズル先端部から溶鋼に伝達されるこ
とによって、微細なAl2O3の溶鋼中での凝集が促進され
て大きな径のAl2O3に成長して浮上分離が容易となるた
め脱酸速度が増大する効果も考えられる。Further, although it is not clear in the experiment of the aqueous solution, as another reason, the ultrasonic waves are transmitted from the nozzle tip to the molten steel, whereby the aggregation of fine Al 2 O 3 in the molten steel is promoted and the large diameter Al The effect of increasing the deoxidation rate is also considered because it grows to 2 O 3 to facilitate floating separation.
いずれにしても第１図、第２図に示す方法によって、超
音波を印加すると溶鋼の脱酸速度が増大し、また、酸素
濃度もより低値とすることが可能である。In any case, by the method shown in FIGS. 1 and 2, when ultrasonic waves are applied, the deoxidation rate of molten steel is increased, and the oxygen concentration can be made lower.
以上の例は取鍋内溶鋼を対象として説明したが、容器は
取鍋に限定されるものではなく、脱ガス装置の真空槽や
還流管および連続鋳造のタンディッシュなどでも実施可
能である。また、溶鋼の脱酸処理を説明したが、本発明
は脱酸処理に限定されるものではなく、超音波を印加し
て気泡を吹込むことで精錬反応の促進を狙うものであ
り、気泡による脱ガス等の精錬反応の促進に有効に適用
可能である。The above example has been described for molten steel in a ladle, but the container is not limited to a ladle, and can be implemented in a vacuum tank of a degassing device, a reflux pipe, a continuous casting tundish, or the like. Further, although the deoxidation treatment of molten steel has been described, the present invention is not limited to the deoxidation treatment, and is intended to promote the refining reaction by blowing bubbles by applying ultrasonic waves. It can be effectively applied to the promotion of refining reactions such as degassing.
本発明によれば、溶融金属の精錬において精錬反応の促
進と効率化に著しい効果を奏する。ADVANTAGE OF THE INVENTION According to this invention, in refining a molten metal, there exists a remarkable effect in promotion of refining reaction and efficiency improvement.
第１図、第２図はそれぞれ本発明の実施例の模式縦断面
図である。 １……金属棒、２……耐火物 ３……Arガス流路、４……超音波振動子 ５……取鍋、６……溶融金属 ７……ノズル、８……二重管の内管 ９……二重管の外管FIG. 1 and FIG. 2 are schematic vertical sectional views of an embodiment of the present invention. 1 ... Metal rod, 2 ... Refractory 3 ... Ar gas flow path, 4 ... Ultrasonic transducer 5 ... Ladle, 6 ... Melted metal 7 ... Nozzle, 8 ... Double tube Tube 9: Double tube outer tube
Claims (2)
当り、ノズルまたは羽口に超音波を印加することを特徴
とする溶融金属の精錬方法。1. A method for refining a molten metal, which comprises applying an ultrasonic wave to a nozzle or a tuyere in blowing gas into the molten metal for refining.
金属棒中にガス通路を形成し、他端に溶融金属中にガス
を吹込むノズルまたは羽口を形成したことを特徴とする
溶融金属の精錬方法。2. An ultrasonic transducer is attached to one end of a metal rod, a gas passage is formed in the metal rod, and a nozzle or tuyere for blowing gas into the molten metal is formed at the other end. Refining method for molten metal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62283138A JPH0765120B2 (en) | 1987-11-11 | 1987-11-11 | Method and apparatus for refining molten metal by ultrasonic wave |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62283138A JPH0765120B2 (en) | 1987-11-11 | 1987-11-11 | Method and apparatus for refining molten metal by ultrasonic wave |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01127624A JPH01127624A (en) | 1989-05-19 |
| JPH0765120B2 true JPH0765120B2 (en) | 1995-07-12 |
Family
ID=17661721
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62283138A Expired - Lifetime JPH0765120B2 (en) | 1987-11-11 | 1987-11-11 | Method and apparatus for refining molten metal by ultrasonic wave |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0765120B2 (en) |
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| JPH0459937A (en) * | 1990-06-28 | 1992-02-26 | Nippon Steel Corp | Method for bubble refining by ultrasonic wave and apparatus therefor |
| CN103056318B (en) | 2008-03-05 | 2017-06-09 | 南线有限责任公司 | As the niobium of the protective wall in motlten metal |
| DK2556176T3 (en) * | 2010-04-09 | 2020-05-04 | Southwire Co Llc | Ultrasonic degassing of molten metals |
| CN102554195A (en) * | 2011-12-31 | 2012-07-11 | 大连理工大学 | Power ultrasonic device for treating high-temperature metal melt under vacuum state and method thereof |
| CN104357618B (en) * | 2014-11-26 | 2016-06-29 | 山东钢铁股份有限公司 | A kind of ultrasound wave metallurgical plant for RH refining furnace |
| CN109295280B (en) * | 2018-11-24 | 2020-08-18 | 宁波市神光电炉有限公司 | Impurity removal device and method for medium-frequency induction smelting furnace |
| US20220048105A1 (en) * | 2020-08-13 | 2022-02-17 | Qingyou Han | Acoustic rotary liquid processor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS564133A (en) * | 1979-06-22 | 1981-01-17 | Olympus Optical Co Ltd | Information display device of automatic strobe |
-
1987
- 1987-11-11 JP JP62283138A patent/JPH0765120B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103889598A (en) * | 2011-10-11 | 2014-06-25 | 南线有限责任公司 | Ultrasonic device with integrated gas delivery system |
| KR20150000458A (en) * | 2011-10-11 | 2015-01-02 | 사우쓰와이어 컴퍼니, 엘엘씨 | Ultrasonic device with integrated gas delivery system |
| CN103889598B (en) * | 2011-10-11 | 2016-02-24 | 南线有限责任公司 | There is the Vltrasonic device of integrated gas delivery system |
| CN109913663A (en) * | 2013-11-18 | 2019-06-21 | 南线有限责任公司 | The ultrasonic probe with gas vent for degassing molten metal |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01127624A (en) | 1989-05-19 |
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