JP2012001779A - Method for desulfurizing steel - Google Patents
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- JP2012001779A JP2012001779A JP2010138980A JP2010138980A JP2012001779A JP 2012001779 A JP2012001779 A JP 2012001779A JP 2010138980 A JP2010138980 A JP 2010138980A JP 2010138980 A JP2010138980 A JP 2010138980A JP 2012001779 A JP2012001779 A JP 2012001779A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 27
- 239000010959 steel Substances 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 20
- 230000003009 desulfurizing effect Effects 0.000 title claims abstract description 8
- 239000002893 slag Substances 0.000 claims abstract description 64
- 239000000203 mixture Substances 0.000 claims abstract description 49
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 31
- 230000023556 desulfurization Effects 0.000 claims abstract description 31
- 229910000272 alkali metal oxide Inorganic materials 0.000 claims abstract description 23
- 238000007670 refining Methods 0.000 claims description 41
- 229910018068 Li 2 O Inorganic materials 0.000 claims description 12
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 10
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 9
- 230000004907 flux Effects 0.000 abstract description 26
- 239000000654 additive Substances 0.000 abstract description 22
- 230000000996 additive effect Effects 0.000 abstract description 20
- 239000007790 solid phase Substances 0.000 abstract description 16
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 abstract description 14
- 239000010436 fluorite Substances 0.000 abstract description 14
- 239000000463 material Substances 0.000 abstract description 12
- 239000002689 soil Substances 0.000 abstract description 6
- 239000000155 melt Substances 0.000 abstract description 2
- 238000005272 metallurgy Methods 0.000 abstract 5
- 229910004282 SiO—MgO Inorganic materials 0.000 abstract 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 52
- 239000000292 calcium oxide Substances 0.000 description 26
- 235000012255 calcium oxide Nutrition 0.000 description 26
- 229910004261 CaF 2 Inorganic materials 0.000 description 17
- 239000011734 sodium Substances 0.000 description 17
- 238000006243 chemical reaction Methods 0.000 description 13
- 239000000126 substance Substances 0.000 description 10
- 238000003723 Smelting Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 6
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 6
- 239000011737 fluorine Substances 0.000 description 6
- 229910052731 fluorine Inorganic materials 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 102200082816 rs34868397 Human genes 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 238000002386 leaching Methods 0.000 description 2
- 241000284466 Antarctothoa delta Species 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910000760 Hardened steel Inorganic materials 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
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Abstract
Description
この発明は、溶鋼の電気炉精錬に続く還元精錬工程である取鍋精錬における精錬スラグ中に含有されるフッ素を減少したフッ素レス技術に関する。 The present invention relates to a fluorine-less technique in which fluorine contained in refining slag in ladle refining is a reduction refining process following electric furnace refining of molten steel.
従来、取鍋精錬では、ＣａＯ、Ａｌ2Ｏ3、ＳｉＯ2などの造滓材をスラグの基本成分として添加して還元スラグを造り、鋼を脱硫する。この取鍋精錬の造滓方法では、滓化性の向上および脱硫の促進を目的として、上記のＣａＯ、Ａｌ2Ｏ3、ＳｉＯ2などからなるスラグの基本成分に、ホタル石のＣａＦ2を添加し、スラグの流動性を確保している。 Conventionally, in ladle refining, steelmaking materials such as CaO, Al 2 O 3 and SiO 2 are added as basic components of slag to produce reduced slag and desulfurize steel. In this ladle refining method, fluorite CaF 2 is added to the basic components of slag composed of CaO, Al 2 O 3 , SiO 2 and the like for the purpose of improving hatchability and promoting desulfurization. The slag fluidity is ensured.
ところで、例えば、脱硫の促進を図るため溶銑に脱硫剤を添加して反応界面おける還元雰囲気を維持し、さらに反応生成物の移動速度を高めるものとした溶銑脱硫材が開発されている（例えば、特許文献１参照。）。 By the way, for example, a hot metal desulfurization material has been developed in which a desulfurization agent is added to the hot metal to maintain a reducing atmosphere at the reaction interface to further promote the desulfurization and further increase the moving speed of the reaction product (for example, (See Patent Document 1).
一方、溶銑の脱硫方法として生石灰のＣａＯやＣａＣ2や炭酸ソーダのＮａ2ＣＯ3などが古くから用いられている。中でも炭酸ソーダのＮａ2ＣＯ3は脱硫能が極めて高く、低硫鋼を安定的に製造する方法として利用されているが、炭酸ソーダを用いると耐火物の溶損が激しいことから、ソーダ灰に酸化鉄を混合した粉体が提案されている。しかし、このもので脱硫すると大きな精錬効果は得られるが、依然耐火物の溶損は激しいものであった。これらを改良して耐火物の要素を大幅に抑制し、低コストで溶鋼脱硫処理する脱硫剤が提案されている（例えば、特許文献２参照。）。 On the other hand, such as Na 2 CO 3 of quicklime CaO and CaC 2 or sodium carbonate is used for a long time as the desulfurization method of hot metal. Among them, sodium carbonate Na 2 CO 3 has an extremely high desulfurization ability and is used as a method for stably producing low-sulfur steel. However, when sodium carbonate is used, the refractory melts severely. Powders mixed with iron oxide have been proposed. However, desulfurization with this material can provide a large refining effect, but the refractory was still severely damaged. There has been proposed a desulfurization agent that improves these and significantly suppresses the elements of the refractory and performs a desulfurization treatment of molten steel at a low cost (for example, see Patent Document 2).
従来の取鍋精錬におけるスラグは、ホタル石のＣａＦ2を添加しているのでフッ素を多く含有している。このために、ホタル石を添加して取鍋精錬したスラグを路盤材などとしてリサイクルして使用する場合、この路盤材を用いた周辺土壌へ路盤材からのフッ素の溶出が問題となる。 The slag in the conventional ladle refining contains a lot of fluorine because CaF 2 of fluorite is added. For this reason, when slag refined with a ladle and added with fluorite is recycled and used as roadbed material, elution of fluorine from the roadbed material into the surrounding soil using this roadbed material becomes a problem.
近年、土壌環境基準にフッ素の溶出量および含有量が規定されているので、それらの規定をクリアしたスラグでなければ路盤材として使用することはできない。また、取鍋耐火物の溶損もスラグ中へのホタル石のＣａＦ2の添加により一層に大きくなる。 In recent years, since the amount and content of fluorine are stipulated in the soil environment standards, it cannot be used as a roadbed material unless it is a slag that satisfies these regulations. Moreover, the melting loss of the ladle refractory is further increased by adding CaF 2 of fluorite to the slag.
そこで、本願発明が解決しようとする課題は、上記の問題を解消することであり、取鍋精錬における取鍋の耐火物の溶損を減少し、さらに取鍋精錬後のスラグを路盤材にする場合に土壌環境基準を満たすスラグとするために、溶鋼の取鍋精錬を新規の造滓剤を用いて低コストで脱硫して実施する方法を提供することである。 Therefore, the problem to be solved by the present invention is to eliminate the above-mentioned problem, reduce the refractory melting of the ladle in ladle refining, and further use the slag after ladle refining as roadbed material In order to obtain a slag that satisfies the soil environmental standards in some cases, the present invention is to provide a method for performing ladle refining of molten steel by desulfurization at a low cost using a novel ironmaking agent.
上記の課題を解決するための本発明の手段は、請求項１の手段では、還元スラグである取鍋精錬用のスラグの組成が、基本組成としてＣａＯ−Ａｌ2Ｏ3−ＳｉＯ2−ＭｇＯからなり、この基本組成を１００ｍｏｌ％とするとき、従来のホタル石のＣａＦ2に代わる添加材として、上記の基本組成にアルカリ酸化物であるＮａ2Ｏ、Ｋ2Ｏ、Ｌｉ2Ｏを０．５〜１０ｍｏｌ％を添加したスラグからなるものとして、溶鋼を取鍋精錬により脱硫することを特徴とする鋼の脱硫方法である。 The means of the present invention for solving the above problem is that, in the means of claim 1, the composition of the slag for ladle refining, which is reduced slag, is CaO—Al 2 O 3 —SiO 2 —MgO as a basic composition. Thus, when the basic composition is 100 mol%, as an additive in place of CaF 2 in the conventional fluorite, 0.52 of Na 2 O, K 2 O, and Li 2 O, which are alkali oxides, are added to the above basic composition. A steel desulfurization method characterized by desulfurizing molten steel by ladle refining as slag added with -10 mol%.
請求項２の手段では、取鍋精錬スラグの基本組成は、質量％で、ＣａＯ：５０〜７０％、Ａｌ2Ｏ3：１０〜４０％、ＳｉＯ2：５〜１５％、ＭｇＯ：２〜１０％であることを特徴とする請求項１の手段の鋼の脱硫方法である。 The means of claim 2, the basic composition of the ladle refining slag, in mass%, CaO: 50~70%, Al 2 O 3: 10~40%, SiO 2: 5~15%, MgO: 2~10 The method of desulfurizing steel according to claim 1, characterized in that the ratio is%.
請求項３の手段では、取鍋精錬用のスラグである還元スラグに添加するアルカリ酸化物がＮａ2Ｏ、Ｋ2ＯおよびＬｉ2Ｏから選択した１種以上であることを特徴とする請求項１又は２に記載の鋼の脱硫方法である。
The means of
この本願の発明の方法において、上記の取鍋精錬スラグの基本組成にアルカリ酸化物を添加する手段により、取鍋精錬スラグの基本組成に従来のホタル石のＣａＦ2を添加した方法の手段における脱硫能と同等か又はそれ以上の脱硫能を確保することができる。 In the method of the invention of this application, desulfurization in the means of the conventional method of adding CaF 2 of fluorite to the basic composition of the ladle refining slag by means of adding an alkali oxide to the basic composition of the above ladle refining slag A desulfurization capacity equal to or higher than the capacity can be ensured.
本発明は、上記の手段に記載の様に、鋼の取鍋精錬における還元スラグの添加材として、還元スラグの基本組成であるＣａＯ−Ａｌ2Ｏ3−ＳｉＯ2−ＭｇＯからなる添加材に、従来のホタル石であるＣａＦ2を添加する代わりに、アルカリ酸化物の適切な量を添加することで、ホタル石のＣａＦ2を添加する以上の脱硫効果が確認された。さらに還元スラグ中におけるＣａＦ2レス化により、取鍋精錬後に得られたスラグを有効利用として路盤材などにリサイクルする際に、周辺土壌へのフッ素の溶出が減少でき、フッ素溶出量が土壌環境基準を超える恐れがなくなった。又、スラグ中にＣａＦ2を含有していないので、ＣａＦ2による取鍋耐火物の溶損もなくなるなど、本発明の手段は優れた効果を奏する。 The present invention, as described in the above means, as an additive for reducing slag in steel ladle refining, an additive consisting of CaO-Al 2 O 3 —SiO 2 —MgO, which is the basic composition of reduced slag, Instead of adding CaF 2 , which is a conventional fluorite, the addition of an appropriate amount of an alkali oxide confirmed a desulfurization effect more than adding CaF 2 of fluorite. Furthermore, by eliminating CaF 2 in the reduced slag, when the slag obtained after ladle refining is recycled to roadbed materials, etc. for effective use, the leaching of fluorine into the surrounding soil can be reduced, and the amount of leaching of fluorine is the soil environment standard The fear of exceeding In addition, since no contain CaF 2 in the slag, such as is also eliminated erosion of ladle refractories by CaF 2, it means of the present invention exhibits an excellent effect.
本発明を実施するための形態について、表および図面を参照して以下に説明する。このためには、取鍋精錬スラグの基本組成として、質量％で、ＣａＯ：５０〜７０％、Ａｌ2Ｏ3：１０〜４０％、ＳｉＯ2：５〜１５％、ＭｇＯ：２〜１０％からなるものとする。この基本組成に、ホタル石のＣａＦ2に代わる添加材として、アルカリ酸化物であるＮａ2Ｏ、Ｋ2Ｏ、Ｌｉ2Ｏのいずれか１種以上を添加して取鍋精錬スラグとしたものとして検討する。 EMBODIMENT OF THE INVENTION The form for implementing this invention is demonstrated below with reference to a table | surface and drawing. For this purpose, the basic composition of the ladle refining slag is, in mass%, CaO: 50 to 70%, Al 2 O 3 : 10 to 40%, SiO 2 : 5 to 15%, MgO: 2 to 10%. Shall be. To this basic composition, one or more of alkali oxides Na 2 O, K 2 O and Li 2 O were added as an alternative to fluorite CaF 2 to make a ladle refining slag. consider.
そこで、上記の検討を表１に示し、以下の（１）〜（５）に区分して説明した。なお、表１におけるΔＧ0は温度１６００Ｋにおけるものである。（１）は精錬スラグの基本組成をＣａＯ、Ａｌ2Ｏ3、ＳｉＯ2、ＭｇＯとして、図１にフラックスＡとして示した。この場合、表１で、スラグの基本組成として主成分である固相のＣａＯで示し、添加材を無添加とした。そのＣａＯの固相率は３３．３％であった。この基本組成では、さらなる添加材は使用しないものであった。この基本組成のみからなる取鍋精錬スラグの自由エネルギーのΔＧ0は、図２に見られるように、温度１６００Ｋで−９０４ｋＪ／ｍｏｌであった。 Therefore, the above examination is shown in Table 1 and described in the following (1) to (5). In Table 1, ΔG 0 is the temperature at 1600K. (1) shows the basic composition of the smelted slag as CaO, Al 2 O 3 , SiO 2 , MgO, and as flux A in FIG. In this case, in Table 1, the basic composition of slag is indicated by solid-phase CaO as the main component, and the additive was not added. The solid phase ratio of CaO was 33.3%. In this basic composition, no additional additives were used. The ΔG 0 of the free energy of the ladle smelting slag consisting only of this basic composition was −904 kJ / mol at a temperature of 1600 K as seen in FIG.
（２）は精錬スラグの基本組成に、さらに、従来のホタル石であるＣａＦ2を添加して取鍋精錬スラグとしたものであり、図１にＣａＦ2として示した。この場合、表１で、（１）と同様に、スラグの基本組成として主成分である固相のＣａＯで示し、そのＣａＯの固相率は２８．０％とし、添加材はＣａＦであった。 (2) is obtained by adding CaF 2 which is a conventional fluorite to the basic composition of the refining slag to obtain a ladle refining slag, which is shown as CaF 2 in FIG. In this case, similarly to (1), in Table 1, the basic composition of slag is represented by solid phase CaO as a main component, the solid phase ratio of CaO was 28.0%, and the additive was CaF. .
以下は精錬スラグの基本組成に、さらにアルカリ酸化物を添加材として取鍋精錬スラグとしたもので、添加材のアルカリ酸化物としてＬｉ2Ｏ、Ｎａ2Ｏ、Ｋ2Ｏを使用するもので、これらを以下の（３）〜（５）で説明した。 The following is a basic composition of smelting slag, and further using an alkali oxide as a ladle smelting slag, and using Li 2 O, Na 2 O, K 2 O as an alkali oxide of the additive, These are described in the following (3) to (5).
（３）は取鍋精錬スラグの基本組成に、添加材としてＬｉ2Ｏを使用したもので、図１にＬｉ2Ｏとして示した。この場合、表１で、（１）と同様に、スラグの基本組成として主成分である固相のＣａＯで示し、そのＣａＯの固相率は３０．１％であった。この取鍋精錬スラグの自由エネルギーのΔＧ0は、図２に見られるように、温度１６００Ｋで−９０８ｋＪ／ｍｏｌであった。 (3) uses Li 2 O as an additive in the basic composition of the ladle smelting slag, and is shown as Li 2 O in FIG. In this case, in Table 1, similarly to (1), the basic composition of slag is indicated by solid phase CaO as the main component, and the solid phase ratio of CaO was 30.1%. The free energy ΔG 0 of this ladle refining slag was −908 kJ / mol at a temperature of 1600 K as seen in FIG.
（４）は取鍋精錬スラグの基本組成に、添加材としてＮａ2Ｏを使用したもので、図１にＮａ2Ｏとして示した。この場合、表１で、（１）と同様に、スラグの基本組成として主成分である固相のＣａＯで示し、固相ＣａＯの固相率は２６．０％であった。この取鍋精錬スラグの自由エネルギーのΔＧ0は、図２に見られるように、温度１６００Ｋで−１２４７ｋＪ／ｍｏｌであった。 (4) uses Na 2 O as an additive in the basic composition of the ladle refining slag, and is shown as Na 2 O in FIG. In this case, in Table 1, similarly to (1), the basic composition of slag is indicated by solid phase CaO as the main component, and the solid phase ratio of solid phase CaO was 26.0%. ΔG 0 of the free energy of this ladle refining slag was −1247 kJ / mol at a temperature of 1600 K as seen in FIG.
（５）は取鍋精錬スラグの基本組成に、添加材としてＫ2Ｏを使用したもので、図１にＫ2Ｏとして示した。この場合、表１で、（１）と同様に、スラグの基本組成として主成分である固相のＣａＯで示し、固相ＣａＯの固相率は２８．６％であった。この取鍋精錬スラグの自由エネルギーのΔＧ0は、図２に見られるように、温度１６００Ｋで−１３８７ｋＪ／ｍｏｌであった。 (5) uses K 2 O as an additive in the basic composition of the ladle smelting slag, and is shown as K 2 O in FIG. In this case, in Table 1, as in (1), the basic composition of slag is represented by solid phase CaO as the main component, and the solid phase ratio of solid phase CaO was 28.6%. ΔG 0 of the free energy of this ladle refining slag was −1387 kJ / mol at a temperature of 1600 K as seen in FIG.
表１に示す検討の結果、（２）の従来のＣａＯにホタル石を添加する場合も、（３）〜（５）のアルカリ酸化物を添加する場合、すなわち取鍋精錬スラグの基本組成に、ホタル石に代わる添加材として、アルカリ酸化物であるＮａ2Ｏ、Ｋ2Ｏ、Ｌｉ2Ｏのいずれかを添加する場合も、脱硫率の高いＣａＯの固相が存在し、この固相率は（１）の基本に比して３．２％〜７．３％低下し、スラグの流動性は向上しており、さらにΔＧ0の値から脱硫反応の駆動力が大である。したがって、取鍋精錬スラグの基本組成にアルカリ酸化物であるＮａ2Ｏ、Ｋ2Ｏ、Ｌｉ2Ｏのいずれかを添加することで、従来のホタル石のＣａＦ2の添加と同等か、それ以上の脱硫能が確保できることが判明した。 As a result of the examination shown in Table 1, when adding fluorite to the conventional CaO of (2), when adding the alkali oxides of (3) to (5), that is, to the basic composition of the ladle smelting slag, When adding any one of alkali oxides Na 2 O, K 2 O, and Li 2 O as an additive instead of fluorite, there is a CaO solid phase with a high desulfurization rate. Compared to the basis of (1), the slag fluidity is improved by 3.2% to 7.3%, and the driving force of the desulfurization reaction is large from the value of ΔG 0 . Therefore, adding any of alkali oxides Na 2 O, K 2 O, Li 2 O to the basic composition of ladle smelting slag is equivalent to or higher than the addition of CaF 2 in conventional fluorite. It was proved that the desulfurization ability of can be secured.
以下に、取鍋精錬における脱硫反応式を熱力学的に化１により示す。取鍋精錬スラグである均一液相のフラックスによる脱硫反応はこの化１により進行する。
本実験におけるフラックスの中の主な塩基性成分はＣａＯおよびアルカリ酸化物であるため、化１の反応の自由エネルギー変化は化２で表される。そこで、上記の脱硫反応式におけるフラックスの反応の自由エネルギー変化を化２により示す。
ここで、フラックス中の硫化物およびメタル中のＳの活量を活量係数を用いて表すと化３の様になる。
化３を化２に代入することにより化４に示すＳ分配比のＬｓが得られる。
化４中のｆ'S 、ａAl、３ＲＴは一定であるため、Ｓの分配値は化５の右辺に比例する値である。
鋼種としてＪＩＳ規格のＳＣＭ４２０を取鍋精錬する際のスラグを基本にして、この鋼成分に質量％で、Ａｌを０．０５０％、Ｓを０．１０％となるように、ＡｌおよびＳを添加して鋼成分を調整した。このＳＣＭ４２０を取鍋精錬により還元精錬する際のフラックス組成の基本組成を表２、表３に示す。当スラグは、ＳＣＭ４２０や下記のＳ４５Ｃのみならず、ＳＣｒ、軸受などの一般鋼やステンレス鋼などにも適用できる。 Based on slag when refining JIS standard SCM420 as a steel type, Al and S are added to this steel component so that the mass percentage is 0.050% for Al and 0.10% for S. And the steel component was adjusted. Tables 2 and 3 show the basic composition of the flux composition when the SCM420 is refining by ladle refining. This slag can be applied not only to SCM420 and S45C described below, but also to general steel such as SCr and bearings, and stainless steel.
鋼種としてＪＩＳ規格のＳ４５Ｃを取鍋精錬する際のスラグを基本にして、この鋼成分に質量％で、Ａｌを０．０５０％、Ｓを０．１０％となるように、ＡｌおよびＳを添加して鋼成分を調整した。このＳ４５Ｃを取鍋精錬により還元精錬する際のフラックス組成の基本組成を表３に示す。 Based on slag when ladle refining JIS S45C as a steel grade, Al and S are added to this steel component so that the mass percentage is 0.050% for Al and 0.10% for S. And the steel component was adjusted. Table 3 shows the basic composition of the flux composition when S45C is refining by ladle refining.
この表２に示すフラックス組成を図１のフラックスＡの基本組成とし、この基本組成を１００ｍｏｌ％としたとき、この基本組成１００ｍｏｌ％のフラックスＡに対して、添加材としてそれぞれＣａＦ2、Ｌｉ2Ｏ、Ｎａ2Ｏ、Ｋ2Ｏを３ｍｏｌ％を添加して全量を１０３ｍｏｌ％として取鍋精錬スラグであるフラックスとした。 When the flux composition shown in Table 2 is the basic composition of flux A in FIG. 1 and the basic composition is 100 mol%, CaF 2 and Li 2 O are added as additives to the flux A having the basic composition of 100 mol%, respectively. Then, 3 mol% of Na 2 O and K 2 O were added to make the total amount 103 mol% to obtain a flux as ladle refining slag.
上記で調整した上記のフラックスを用いて模式的な取鍋精錬として、シリコニット縦型炉により１５００°Ｃ、３５０ｃｃ／ｍｉｎのＡｒガス雰囲気中でＳＣＭ４２０の溶鋼を精錬した。この溶鋼を１２０ｇ、フラックスを２０ｇずつ５分毎にサンプリングし、赤外線吸収法によりＳ分析を実施した。このＳ分析結果を、縦軸をＳ／ＳＯ、横軸を時間（ｍｉｎ）とするグラフとして図１に示す。なお、グラフにおいてフラックスＡはフラックスの基本成分からなるものである。この基本成分のフラックスＡに添加材としてＣａＦ2、Ｌｉ2Ｏ、Ｎａ2Ｏ、Ｋ2Ｏを３ｍｏｌ％加えた場合のＳ分析値のＳ／ＳＯを示す。この結果、脱硫は、フラックスＡ＜ＣａＦ2＜Ｌｉ2Ｏ＜Ｎａ2Ｏ＜Ｋ2Ｏの順に、早くなった。 As a typical ladle refining using the above-prepared flux, molten steel of SCM420 was refined in a siliconite vertical furnace in an Ar gas atmosphere of 1500 ° C. and 350 cc / min. 120 g of this molten steel and 20 g of flux were sampled every 5 minutes, and S analysis was performed by an infrared absorption method. The S analysis results are shown in FIG. 1 as a graph with the vertical axis representing S / SO and the horizontal axis representing time (min). In the graph, flux A is composed of basic components of the flux. S / SO of the S analysis value when 3 mol% of CaF 2 , Li 2 O, Na 2 O, and K 2 O is added as an additive to the basic component flux A is shown. As a result, desulfurization was accelerated in the order of flux A <CaF 2 <Li 2 O <Na 2 O <K 2 O.
上記した脱硫反応式である化２の式の自由エネルギーのΔＧ0を縦軸に、温度（ｋ）を横軸にとり、フラックスの基本成分をＣａＯのみとするもの、基本成分に添加材をそれぞれＬｉ2Ｏ、Ｎａ2Ｏ、Ｋ2Ｏとして添加した脱硫反応の自由エネルギー変化を示して図２とした。この結果、上記した表１の基本とアルカリ酸化物に示しているものにおいて、添加材としてアルカリ酸化物を添加するものでは、固相率が基本よりも３〜４％低下し、流動性が確保され、脱硫反応の駆動力が大となっていることが示された。 In the above desulfurization reaction formula, the free energy ΔG 0 of the formula 2 is plotted on the vertical axis, the temperature (k) is plotted on the horizontal axis, the basic component of the flux is only CaO, and the additive is added to the basic component. Changes in the free energy of the desulfurization reaction added as 2 O, Na 2 O, and K 2 O are shown in FIG. As a result, in the basic and alkaline oxides shown in Table 1 above, in the case where an alkaline oxide is added as an additive, the solid phase ratio is reduced by 3 to 4% from the basic, ensuring fluidity. It was shown that the driving force of the desulfurization reaction is large.
上記の実施例１、実施例２では、フラックス組成の基本組成が表２、表３に示すものであり、添加材としてのアルカリ酸化物を表１に示すＣａＯの固相率となるように適切量添加したものであるが、この実施例１、実施例２と同様にアルカリ酸化物を適切量としながらも、フラックス組成の基本組成のＣａＯが表２、表３よりも少ない場合、すなわち、質量％で、ＣａＯ：４６％、Ａｌ2Ｏ3：４２％、Ｓｉ2Ｏ：８％、ＭｇＯ：４％とするときは、ＣａＯが少なすぎて流動性及び脱硫反応が悪く×であった。これに反し、フラックス組成の基本組成のＣａＯが表２、表３よりも多い場合、フラックス組成の基本組成のＣａＯが、質量％で、７０％を超えるとスラグの融点が高くなりすぎ、×であった。 In the above Example 1 and Example 2, the basic composition of the flux composition is as shown in Tables 2 and 3, and the alkali oxide as the additive is appropriately set to have a solid phase ratio of CaO shown in Table 1. Although it is added in an amount, the basic composition of the flux composition is less than those in Tables 2 and 3 while the alkali oxide is set to an appropriate amount in the same manner as in Examples 1 and 2, that is, mass. in%, CaO: 46%, Al 2 O 3: 42%, Si 2 O: 8%, MgO: when the 4%, CaO is too small fluidity and desulfurization reaction was bad ×. On the other hand, when the CaO of the basic composition of the flux composition is larger than those in Tables 2 and 3, the CaO of the basic composition of the flux composition is in mass%, and when it exceeds 70%, the melting point of the slag becomes too high. there were.
上記の実施例１、２では、フラックス組成の基本組成が表２、表３に示すもので、添加材としてのアルカリ酸化物（Ｎａ2Ｏ）を０．３〜１０ｍｏｌ％添加したものであるが、添加材としてのアルカリ酸化物が少ない場合、すなわち０．３ｍｏｌ％で、０．５ｍｏｌ％より少ないときは、添加物の効果がなくなり、×であった。これに反し、アルカリ酸化物が多い場合、すなわち、ｍｏｌ％で、１０％添加しても、脱硫に差がなく、コストアップとなるので×であった。 In the above Examples 1 and 2, the basic composition of the flux composition is shown in Tables 2 and 3, and 0.3 to 10 mol% of an alkali oxide (Na 2 O) as an additive is added. When the amount of the alkali oxide as the additive is small, that is, 0.3 mol% and less than 0.5 mol%, the effect of the additive is lost and the result is x. On the other hand, when the amount of alkali oxide is large, that is, mol%, even if 10% is added, there is no difference in desulfurization and the cost is increased.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS4913016A (en) * | 1972-05-19 | 1974-02-05 | ||
| JPS5594411A (en) * | 1979-01-11 | 1980-07-17 | Ishii Sangyo Kk | Production of desulfurizer |
| JP2002060832A (en) * | 2000-08-08 | 2002-02-28 | Nippon Magnetic Dressing Co Ltd | Calcium aluminate-based desulfurizing agent |
| JP2002285217A (en) * | 2001-03-23 | 2002-10-03 | Kobe Steel Ltd | Dephosphorizing agent and desulfurizing agent for molten iron and molten steel |
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| JPS4913016A (en) * | 1972-05-19 | 1974-02-05 | ||
| JPS5594411A (en) * | 1979-01-11 | 1980-07-17 | Ishii Sangyo Kk | Production of desulfurizer |
| JP2002060832A (en) * | 2000-08-08 | 2002-02-28 | Nippon Magnetic Dressing Co Ltd | Calcium aluminate-based desulfurizing agent |
| JP2002285217A (en) * | 2001-03-23 | 2002-10-03 | Kobe Steel Ltd | Dephosphorizing agent and desulfurizing agent for molten iron and molten steel |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US9127327B2 (en) | 2011-03-31 | 2015-09-08 | Nippon Steel & Sumitomo Metal Corporation | Environmentally friendly flux for molten steel desulfurization |
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