JPH0459916A - Method for degassing from molten metal - Google Patents
Method for degassing from molten metalInfo
- Publication number
- JPH0459916A JPH0459916A JP16842990A JP16842990A JPH0459916A JP H0459916 A JPH0459916 A JP H0459916A JP 16842990 A JP16842990 A JP 16842990A JP 16842990 A JP16842990 A JP 16842990A JP H0459916 A JPH0459916 A JP H0459916A
- Authority
- JP
- Japan
- Prior art keywords
- molten steel
- molten metal
- porous material
- molten
- pipe
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 43
- 239000002184 metal Substances 0.000 title claims abstract description 43
- 238000007872 degassing Methods 0.000 title claims abstract description 19
- 238000000034 method Methods 0.000 title description 12
- 239000011148 porous material Substances 0.000 claims abstract description 21
- 238000010438 heat treatment Methods 0.000 claims description 5
- 239000000126 substance Substances 0.000 claims 1
- 229910000831 Steel Inorganic materials 0.000 abstract description 43
- 239000010959 steel Substances 0.000 abstract description 43
- 239000007789 gas Substances 0.000 abstract description 22
- 239000001257 hydrogen Substances 0.000 abstract description 13
- 229910052739 hydrogen Inorganic materials 0.000 abstract description 13
- 230000007423 decrease Effects 0.000 abstract description 7
- 125000004435 hydrogen atom Chemical class [H]* 0.000 abstract 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 238000006356 dehydrogenation reaction Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 150000002431 hydrogen Chemical class 0.000 description 5
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 230000003247 decreasing effect Effects 0.000 description 3
- 229910052748 manganese Inorganic materials 0.000 description 3
- 239000011572 manganese Substances 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 229910002090 carbon oxide Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は溶融金属からの脱ガス方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for degassing molten metal.
従来の技術
溶融金属中に水素、酸素、窒素、−酸化炭素ガスは下記
のように溶解する。BACKGROUND OF THE INVENTION Hydrogen, oxygen, nitrogen, and carbon oxide gases are dissolved in molten metal as follows.
Ｎ２→２ Ｈ（＋）
０２→２０ （２）
Ｎ２→２ Ｎ （３）
ＧＯ４Ｃ＋０（４）
ここで、Ｈ７，０２、Ｎ、、Ｃ：０は気体中のガスを、
Ｈｌｏ、Ｎ、Ｃは溶融金属中に溶解したガスを示す。N2→2 H(+) 02→20 (2) N2→2 N (3) GO4C+0(4) Here, H7,02,N,,C:0 represents the gas in the gas,
Hlo, N, and C represent gases dissolved in the molten metal.
従って、従来は、溶融金属中のガスを除去する方法とし
ては、溶融金属を減圧下に曝し、水素、酸素、窒素、−
酸化炭素ガスの分圧を小さくすることによって、各々の
溶解水素、溶解酸素、溶解窒素、溶解炭素を少なくする
方法が一般的に行われている。この場合、溶融金属内部
からガスが発生するため、脱ガス速度を速くする程、溶
融金属は飛散し、減圧容器及び減圧ポンプを汚染するた
め、減圧容器内及び減圧ポンプの清掃をする必要があり
、生産性を低下させる等の問題があった。Therefore, conventional methods for removing gases in molten metal include exposing the molten metal to reduced pressure to remove hydrogen, oxygen, nitrogen, and
A commonly used method is to reduce the amount of each of dissolved hydrogen, dissolved oxygen, dissolved nitrogen, and dissolved carbon by reducing the partial pressure of carbon oxide gas. In this case, gas is generated from inside the molten metal, so the faster the degassing rate is, the more the molten metal will scatter and contaminate the vacuum container and vacuum pump, so it is necessary to clean the vacuum container and vacuum pump. , there were problems such as reduced productivity.
又、減圧下に溶融金属を曝すことにより、溶融金属その
ものが蒸発し、溶融金属の歩留を低下させる等の問題も
あった。更に、ガスを除去しようとする溶融金属は専用
の減圧容器に移し替える必要があり、作業性を悪くする
等の問題もあった。Furthermore, by exposing the molten metal to reduced pressure, the molten metal itself evaporates, resulting in a reduction in the yield of the molten metal. Furthermore, it is necessary to transfer the molten metal from which the gas is to be removed to a dedicated vacuum container, which poses problems such as poor workability.
本発明は、これらの問題を解決し、安価で且つ効率的に
溶融金属からガスを除去するために開発されたものであ
る。The present invention was developed to solve these problems and to remove gas from molten metal inexpensively and efficiently.
課題を解決するための手段
その特徴とするところは、溶融金属は通過させないが、
ガスを通過させる多孔質物質の溶融金属に接触する表面
を３００℃以上にした後、多孔質物質の一面を溶融金属
に接触させ、他方の面を減圧下に曝すことにより、溶融
金属が含有するガスを除去する脱ガス方法である。Means to solve the problem The feature is that it does not allow molten metal to pass through, but
After the surface of the porous material that allows gas to pass through that is in contact with the molten metal is heated to 300°C or higher, one side of the porous material is brought into contact with the molten metal and the other side is exposed to reduced pressure to remove the molten metal. This is a degassing method that removes gas.
従来法による脱ガス方法は、溶融金属の自由表面を直接
減圧下に曝すため、溶融金属内部で生成したガスが溶融
金属の自由表面で破裂し、溶融金属の飛散を発生させ、
減圧容器及び減圧ポンプを汚染することとなる。又、溶
融金属自由表面を直接減圧下に曝すため、Ｎ気圧の低い
溶融金属の場合は溶融金属そのものが蒸発することもあ
る。つまり、従来法はガスを除去しようとする溶融金属
を直接減圧下に曝すために種々の問題が発生し、脱ガス
処理の生産性の低下、歩留の低下を招いている。In the conventional degassing method, the free surface of the molten metal is directly exposed to reduced pressure, so the gas generated inside the molten metal ruptures on the free surface of the molten metal, causing the molten metal to scatter.
This will contaminate the vacuum vessel and vacuum pump. Furthermore, since the free surface of the molten metal is directly exposed to reduced pressure, the molten metal itself may evaporate if the N atmosphere is low. In other words, in the conventional method, various problems occur because the molten metal from which gas is to be removed is directly exposed to a reduced pressure, resulting in a decrease in productivity and yield in the degassing process.
そこで、本発明は溶融金属内部で生成したガスを減圧下
に直接放出しない方法について種々の検討を行った。そ
の結果、溶融金属は通過させないが、ガスを通過させる
多孔質物質を介して、溶融金属内部で生成したガスを減
圧下に放出すれば、従来法の溶融金属の飛散及び溶融金
属の蒸発を防止しつつ、溶融金属からガスを除去できる
ことを見出したものである。Therefore, in the present invention, various studies have been conducted on methods that do not directly release the gas generated inside the molten metal under reduced pressure. As a result, if the gas generated inside the molten metal is released under reduced pressure through a porous material that does not allow the molten metal to pass through, but allows gas to pass through, it prevents the molten metal from scattering and the molten metal from evaporating in the conventional method. It has been discovered that gas can be removed from molten metal at the same time.
以下に溶鋼から水素を除去する場合を例にして、詳細に
説明を行う、従来法で、溶鋼から脱水素を行う場合は、
溶鋼の入った容器ごとタンクの中に置き、真空ポンプで
タンク内を減圧にし、脱水素する真空溶解炉方式の脱ガ
ス方法、あるいは溶鋼を減圧槽内に送り込むＲＨ脱ガス
、ＤＨ脱ガス等により脱水素する脱ガス方法が採用され
ていた。この場合、タンク内あるいは槽内の真空度をあ
げると、水素分圧は低下し、溶鋼中に溶解する平衡水素
ガス濃度は減少するので、溶鋼中から水素ガス気泡が発
生する。この水素ガスは溶鋼静圧が小さくなる溶鋼自由
表面に近づくにしたがい、急激に気泡径が増大し、溶鋼
自由表面から離脱するが、離脱の際、溶鋼を飛散するこ
とになる。また、通常工業的に使われる溶鋼はマンガン
を含有しているが、マンガンの蒸気圧は１２９２℃で１
ｍｍＨｇである。タンク内あるいは槽内の真空度が１
ｍｍＨｇ以上の高真空度になると、マンガンは蒸発し
、溶鋼成分を変化させるばかりでなく、マンガン蒸気で
タンク内、槽内、あるいは真空ポンプを汚染する恐れが
ある。The following is a detailed explanation using the case of removing hydrogen from molten steel as an example. When dehydrogenating molten steel using the conventional method,
A degassing method using a vacuum melting furnace method in which a container containing molten steel is placed in a tank and the tank is depressurized using a vacuum pump to dehydrogenate it, or RH degassing, DH degassing, etc. in which molten steel is sent into a decompression tank A degassing method of dehydrogenation was used. In this case, when the degree of vacuum inside the tank or vessel is increased, the hydrogen partial pressure decreases and the equilibrium concentration of hydrogen gas dissolved in the molten steel decreases, so hydrogen gas bubbles are generated from the molten steel. As this hydrogen gas approaches the free surface of the molten steel where the static pressure of the molten steel decreases, its bubble diameter rapidly increases and it leaves the free surface of the molten steel, but when it leaves, it scatters the molten steel. In addition, the molten steel normally used industrially contains manganese, and the vapor pressure of manganese is 1 at 1292°C.
mmHg. The degree of vacuum inside the tank or tank is 1
When the degree of vacuum reaches a high degree of vacuum of mmHg or more, manganese not only evaporates and changes the molten steel composition, but also has the risk of contaminating the inside of the tank, bath, or vacuum pump with manganese vapor.
本発明は溶融金属は通過させないが、ガスを通過させる
多孔質物質の一面を溶融金属に接触させ、他方の面を減
圧下に曝すことにより、溶融金属が含有するガスを除去
する脱ガス方法である。The present invention is a degassing method in which the gas contained in the molten metal is removed by bringing one side of a porous material that does not allow the molten metal to pass through but allows gas to pass through to the molten metal and exposes the other side to a reduced pressure. be.
第１図にしたがって、本発明を溶鋼からの水素を除去す
る方法について説明する。容器１に保持した溶鋼２の中
に、片端を封じた多孔質物質からなるバイブ３を浸漬し
、バイブの他端を真空ポンプ４に連結し、バイブ内を減
圧する。これによって、溶鋼に接したバイブの外側で発
生した水素５は、バイブの内側に吸引され、真空ポンプ
４により排気される。逆に、第２図に示したように、容
器１に保持された溶鋼２を多孔質物質からなるバイブ３
の中を通過させ、容器」０に移す際、バイブ３の外側を
カバー６で覆い、バイブ３とカバー間の空間と真空ポン
プ４に連結し、バイブ３とカバー間の空間を減圧しても
良い、容器の耐雪方法は第２図のように水平方向だけで
なく、上下方向に配置しても脱ガス効果は変わりない、
多孔質物質としては、通常溶鋼処理に使用されている耐
火物で気孔率１０〜３０％あれば十分である。A method of removing hydrogen from molten steel according to the present invention will be explained with reference to FIG. A vibrator 3 made of a porous material with one end sealed is immersed in molten steel 2 held in a container 1, and the other end of the vibrator is connected to a vacuum pump 4 to reduce the pressure inside the vibrator. As a result, hydrogen 5 generated on the outside of the vibrator in contact with the molten steel is drawn into the inside of the vibrator and exhausted by the vacuum pump 4. On the other hand, as shown in FIG. 2, the molten steel 2 held in the container 1 is transferred to
When passing through the inside of the vibrator 3 and transferring it to the container 0, cover the outside of the vibrator 3 with a cover 6, connect the space between the vibrator 3 and the cover to the vacuum pump 4, and reduce the pressure in the space between the vibrator 3 and the cover. Good, the snowproofing method for containers is not only horizontal as shown in Figure 2, but even if they are placed vertically, the degassing effect remains the same.
As the porous material, a refractory material normally used for processing molten steel with a porosity of 10 to 30% is sufficient.
しかし、この際、多孔質物質を常温のまま溶鋼と接触さ
せると脱ガス速度が急激に低下することを見出した。こ
の原因を解明するため種々の検討を行った結果、多孔質
物質を常温のまま溶鋼と接触させると多孔質物質の表面
に溶鉄が凝固し、多孔質物質の表面を被覆し、脱ガス速
度が低下することが分かった。これを改善するため種々
の実験を行った結果、多孔質物質の表面を３００℃以上
、望ましくは９００℃以上にした後、溶鋼と接触させれ
ば、工業的には脱ガス速度が低下しないことを見出した
ものである。これは、多孔質物質の表面を３００℃以上
にすれば、例え多孔質物質の表面に一時的に溶鋼が凝固
したとしても、溶鋼の熱で再溶解する時間が短く、工業
的には脱ガス速度が低下しないものと考えられる。尚、
多孔質物質の加熱方法としては、通常のガスバーナー加
熱方式、通電方式、あるいは溶鋼等の高温物体に一度接
触させる方法等の通常の耐火物加熱方式で十分である。However, at this time, it was discovered that when the porous material was brought into contact with molten steel at room temperature, the degassing rate decreased rapidly. As a result of conducting various studies to elucidate the cause of this, we found that when a porous material is brought into contact with molten steel at room temperature, molten iron solidifies on the surface of the porous material, coats the surface of the porous material, and slows down the degassing rate. It was found that it decreased. As a result of conducting various experiments to improve this problem, we found that if the surface of the porous material is brought into contact with molten steel after heating it to 300°C or higher, preferably 900°C or higher, the degassing rate will not decrease industrially. This is what we discovered. This is because if the surface of the porous material is heated to 300°C or higher, even if molten steel temporarily solidifies on the surface of the porous material, the time for remelting it with the heat of the molten steel will be short, making it difficult to degas industrially. It is thought that the speed will not decrease. still,
As a heating method for the porous material, a normal gas burner heating method, an electric current method, or a normal refractory heating method such as once contacting a high temperature object such as molten steel is sufficient.
実施例１
第１表に示した下端を閉じた多孔質パイプを、２０分間
バーナー加熱し、表面温度を３００℃にした後、１００
ｋｇ溶解炉で第２表に示した成分に調整した溶鋼に２０
ｃｍ浸漬し、多孔質パイプ内を真空ポンプで１ ｔｉｍ
Ｈｇまで減圧し、３０分間脱水素処理をした。尚、溶鋼
表面は１気圧のアルゴンでシールした。初期水素８．３
ｐｐｍの溶鋼が、処理後＋、ｅｐｐｍまで低下した。尚
、溶鋼表面からは溶鋼の飛散は認められなかった。Example 1 The porous pipe shown in Table 1 with its lower end closed was heated with a burner for 20 minutes to reach a surface temperature of 300°C, and then
20 kg of molten steel adjusted to the composition shown in Table 2 in a melting furnace.
immersed in the porous pipe for 1 tim with a vacuum pump.
The pressure was reduced to Hg, and dehydrogenation treatment was performed for 30 minutes. The surface of the molten steel was sealed with argon at 1 atm. Initial hydrogen 8.3
ppm of molten steel decreased to +, eppm after treatment. Incidentally, no molten steel was observed to be scattered from the molten steel surface.
比較例１
第１表に示した下端を閉じた多孔質パイプを常温のまま
、１００ｋｇ溶解炉で第２表に示した成分に調整した溶
鋼に２０ｃ＋ｓ浸漬し、多孔質パイプ内を真空ポンプで
１ ｍｍＨｇまで減圧し、３０分間脱水素処理をした。Comparative Example 1 A porous pipe shown in Table 1 with its lower end closed was immersed in molten steel adjusted to the composition shown in Table 2 in a 100 kg melting furnace at room temperature for 20 c+s, and the inside of the porous pipe was heated with a vacuum pump for 1 hour. The pressure was reduced to mmHg, and dehydrogenation treatment was performed for 30 minutes.
尚、溶鋼表面は１気圧のアルゴンでシールした。初期水
素６．２ＰＰＭの溶鋼が、処理後も５．９ｐｐｍであり
脱水素の効果は認められなかった。尚、実施例１と同様
に溶鋼表面からは溶鋼の飛散は認められなかった。The surface of the molten steel was sealed with argon at 1 atm. The molten steel, which had an initial hydrogen content of 6.2 ppm, had a hydrogen content of 5.9 ppm even after the treatment, and no dehydrogenation effect was observed. Note that, as in Example 1, no molten steel was observed to scatter from the molten steel surface.
比較例２
１００ｋｇ溶解炉で第２表に示した成分に調整した溶鋼
表面を真空ポンプで１薦冒Ｈｇまで減圧し、３０分間脱
水素処理をした。初期水素６．２ｐｐｍの溶鋼が、処理
ｖｋ１．７ｐｐｍであり脱水素の効果は認められたが、
溶鋼が激しく飛散し、溶解炉上部に多量の地金が付着し
た。Comparative Example 2 The surface of the molten steel, which had been adjusted to the composition shown in Table 2 in a 100 kg melting furnace, was depressurized to 1.0% Hg using a vacuum pump and subjected to dehydrogenation treatment for 30 minutes. The molten steel with an initial hydrogen concentration of 6.2 ppm had a treated vk of 1.7 ppm, and the dehydrogenation effect was recognized, but
Molten steel was violently scattered and a large amount of metal was attached to the upper part of the melting furnace.
（以下余白）
発明の効果
本発明によれば、従来の脱ガス方法と比較して、溶融金
属の飛散がなく、容易に且つ確実に溶融金属の脱ガスが
でき、また、工業的規模で正確な脱ガスができる等の優
れた効果が得ることを可能にした。(Left below) Effects of the Invention According to the present invention, compared to conventional degassing methods, molten metal can be easily and reliably degassed without molten metal scattering, and can be accurately degassed on an industrial scale. This makes it possible to obtain excellent effects such as effective degassing.
第１図、第２図は本発明の実施方法の一例を示す説明図
である。
１．１０−−−容器、２９０．溶鋼、３００．バイブ、
４−・中真空ポンプ、５φｅ・水素、６１１−・カバーFIGS. 1 and 2 are explanatory diagrams showing an example of a method of implementing the present invention. 1.10---Container, 290. Molten steel, 300. vibrator,
4-・Medium vacuum pump, 5φe・Hydrogen, 611-・Cover
Claims (1)
質の溶融金属に接触する表面を３００℃以上にした後、
多孔質物質の一面を溶融金属に接触させ、他方の面を減
圧下に曝すことにより、溶融金属が含有するガスを除去
することを特徴とする脱ガス方法。After heating the surface of the porous material that contacts the molten metal to 300°C or higher, which does not allow the molten metal to pass through, but allows the gas to pass through,
A degassing method characterized by removing gas contained in molten metal by bringing one side of a porous substance into contact with molten metal and exposing the other side to a reduced pressure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16842990A JPH0459916A (en) | 1990-06-28 | 1990-06-28 | Method for degassing from molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16842990A JPH0459916A (en) | 1990-06-28 | 1990-06-28 | Method for degassing from molten metal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0459916A true JPH0459916A (en) | 1992-02-26 |
Family
ID=15867957
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16842990A Pending JPH0459916A (en) | 1990-06-28 | 1990-06-28 | Method for degassing from molten metal |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0459916A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008035584A1 (en) * | 2006-09-20 | 2008-03-27 | Mitsui Chemicals, Inc. | Polyolefin composition |
| CN109985976A (en) * | 2019-04-21 | 2019-07-09 | 苏州鲁卡斯金属科技有限公司 | A kind of inflation mode buries metallic conduit method and its equipment |
-
1990
- 1990-06-28 JP JP16842990A patent/JPH0459916A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008035584A1 (en) * | 2006-09-20 | 2008-03-27 | Mitsui Chemicals, Inc. | Polyolefin composition |
| CN109985976A (en) * | 2019-04-21 | 2019-07-09 | 苏州鲁卡斯金属科技有限公司 | A kind of inflation mode buries metallic conduit method and its equipment |
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