JP5862738B2 - Refining vessel for hot metal desulfurization treatment - Google Patents
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- JP5862738B2 JP5862738B2 JP2014191218A JP2014191218A JP5862738B2 JP 5862738 B2 JP5862738 B2 JP 5862738B2 JP 2014191218 A JP2014191218 A JP 2014191218A JP 2014191218 A JP2014191218 A JP 2014191218A JP 5862738 B2 JP5862738 B2 JP 5862738B2
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- 239000002184 metal Substances 0.000 title claims description 143
- 229910052751 metal Inorganic materials 0.000 title claims description 143
- 238000006477 desulfuration reaction Methods 0.000 title claims description 107
- 230000023556 desulfurization Effects 0.000 title claims description 104
- 238000007670 refining Methods 0.000 title claims description 71
- 238000011282 treatment Methods 0.000 title claims description 35
- 239000011449 brick Substances 0.000 claims description 73
- 238000003723 Smelting Methods 0.000 claims description 40
- 230000003009 desulfurizing effect Effects 0.000 claims description 39
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 34
- 238000010276 construction Methods 0.000 claims description 20
- 238000010907 mechanical stirring Methods 0.000 claims description 20
- 229910052742 iron Inorganic materials 0.000 claims description 17
- 230000002093 peripheral effect Effects 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 description 52
- 238000003756 stirring Methods 0.000 description 41
- 238000000034 method Methods 0.000 description 33
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 28
- 238000012360 testing method Methods 0.000 description 17
- 239000000292 calcium oxide Substances 0.000 description 14
- 235000012255 calcium oxide Nutrition 0.000 description 14
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 12
- 235000011941 Tilia x europaea Nutrition 0.000 description 12
- 239000004571 lime Substances 0.000 description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 238000013019 agitation Methods 0.000 description 9
- 239000006185 dispersion Substances 0.000 description 9
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- 238000006243 chemical reaction Methods 0.000 description 8
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- 239000007789 gas Substances 0.000 description 6
- 238000002474 experimental method Methods 0.000 description 5
- 229910052717 sulfur Inorganic materials 0.000 description 5
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 4
- 238000005520 cutting process Methods 0.000 description 4
- 238000006722 reduction reaction Methods 0.000 description 4
- 239000011819 refractory material Substances 0.000 description 4
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- 229920006395 saturated elastomer Polymers 0.000 description 3
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 235000019738 Limestone Nutrition 0.000 description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 2
- 239000012159 carrier gas Substances 0.000 description 2
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- 239000010959 steel Substances 0.000 description 2
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- 239000002699 waste material Substances 0.000 description 2
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- 239000005997 Calcium carbide Substances 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 229910000519 Ferrosilicon Inorganic materials 0.000 description 1
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 description 1
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
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- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 235000011116 calcium hydroxide Nutrition 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
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- 239000010459 dolomite Substances 0.000 description 1
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- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000010436 fluorite Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000012447 hatching Effects 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
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- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 238000007634 remodeling Methods 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- CLZWAWBPWVRRGI-UHFFFAOYSA-N tert-butyl 2-[2-[2-[2-[bis[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]amino]-5-bromophenoxy]ethoxy]-4-methyl-n-[2-[(2-methylpropan-2-yl)oxy]-2-oxoethyl]anilino]acetate Chemical compound CC1=CC=C(N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)C(OCCOC=2C(=CC=C(Br)C=2)N(CC(=O)OC(C)(C)C)CC(=O)OC(C)(C)C)=C1 CLZWAWBPWVRRGI-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Furnace Housings, Linings, Walls, And Ceilings (AREA)
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
Description
本発明は、インペラーを備えた機械攪拌式脱硫装置を用いて溶銑を脱硫処理するための脱硫処理用精錬容器及び脱硫処理方法に関し、詳しくは、溶銑を収容する精錬容器底部に傾斜勾配を設けるなどして底部形状を精錬容器の中心軸に対して軸対称ではない形状とすることで、インペラーにより生成される渦流を乱し、この乱れによって添加した脱硫剤を効果的に溶銑中に分散させ、高い脱硫率で脱硫することのできる脱硫処理用精錬容器及び脱硫処理方法に関する。 The present invention relates to a desulfurization refining vessel and a desulfurization processing method for desulfurizing hot metal using a mechanically stirred desulfurization apparatus equipped with an impeller, and more specifically, providing an inclined gradient at the bottom of the refining vessel containing hot metal, etc. Then, by making the bottom shape a shape that is not axisymmetric with respect to the central axis of the smelting vessel, the vortex generated by the impeller is disturbed, and the desulfurization agent added by this disturbance is effectively dispersed in the hot metal, The present invention relates to a desulfurization refining vessel and a desulfurization treatment method that can be desulfurized at a high desulfurization rate.
高炉で溶製された溶銑から鋼を製造するにあたり、高炉から出銑された溶銑には、鋼の品質に悪影響を及ぼす硫黄（Ｓ）が０．０４〜０．０５質量％程度の高濃度で含まれている。しかも、次工程の転炉精錬工程では、酸化精錬による不純物の除去を目的としていることから、主として還元反応により除去される硫黄の除去は余り期待できず、そこで、他の含有成分などの影響から脱硫しやすい溶銑の段階において、要求される品質に応じて、種々の方法によって脱硫処理が行われている。 When manufacturing steel from hot metal melted in a blast furnace, the hot metal discharged from the blast furnace has a high concentration of sulfur (S), which has an adverse effect on the quality of steel, of about 0.04 to 0.05 mass%. include. Moreover, since the next converter refining process is aimed at removing impurities by oxidative refining, the removal of sulfur mainly removed by the reduction reaction cannot be expected so much. In the hot metal stage where desulfurization is easy, desulfurization treatment is performed by various methods according to the required quality.
この溶銑の脱硫処理技術の１つとして、溶銑中に浸漬させたインペラー（「回転羽根」または「回転翼」とも呼ぶ）を機械的に回転させて溶銑を攪拌しながら脱硫剤を添加し、添加した脱硫剤を溶銑中に巻き込ませて脱硫する方法（「機械攪拌式脱硫法」という）が広く行われている。機械攪拌式脱硫法のうちで、インペラーを攪拌体（スターラー）として用いる方法はＫＲ法とも呼ばれており、また、機械的に溶銑と脱硫剤とを攪拌させて脱硫する装置は、機械攪拌式脱硫装置と呼ばれている。この機械攪拌式脱硫法においては、脱硫剤として比較的安価な生石灰（ＣａＯ）を主成分とするものが用いられており、また、脱硫反応は還元性雰囲気で促進されることから、Ａｌなどの脱酸剤の添加を併用する場合も行われている。 As one of the desulfurization treatment techniques for hot metal, a desulfurizing agent is added while stirring the hot metal by mechanically rotating an impeller (also called “rotary blade” or “rotary blade”) immersed in the hot metal. A method of desulfurizing a desulfurizing agent that has been entrained in hot metal (referred to as “mechanical stirring type desulfurization method”) is widely used. Among mechanical stirring type desulfurization methods, a method using an impeller as a stirrer (stirrer) is also called a KR method. An apparatus for mechanically stirring hot metal and a desulfurizing agent is a mechanical stirring type. It is called desulfurization equipment. In this mechanical stirring type desulfurization method, a relatively low-priced quicklime (CaO) as a main component is used as a desulfurization agent, and the desulfurization reaction is promoted in a reducing atmosphere. It is also carried out when a deoxidizer is added.
ところで、生石灰は溶銑に比べて比重が小さく且つ溶銑との濡れ性が悪いため、脱硫剤である生石灰が溶銑中に侵入・分散しにくく、反応効率が低いという課題がある。溶銑上で浮遊する生石灰は、ほとんど脱硫反応には寄与しない。そこで、溶銑中への生石灰の分散を促進させ、脱硫反応効率を向上させる技術が幾つか提案されている。 By the way, quick lime has a specific gravity smaller than that of hot metal and has poor wettability with hot metal, so that quick lime, which is a desulfurizing agent, is difficult to enter and disperse in hot metal, resulting in low reaction efficiency. Quick lime floating on the hot metal hardly contributes to the desulfurization reaction. In view of this, several techniques for promoting the dispersion of quicklime in hot metal and improving the efficiency of the desulfurization reaction have been proposed.
例えば、特許文献１には、インペラーによる回転攪拌中の溶銑へ成分調整剤を添加するにあたり、溶銑を機械的に攪拌して溶銑の流れを形成するとともに、この流れの中に障害物を設け、該障害物の後方に惹起される乱流中へ成分調整剤を添加する方法が提案されている。特許文献１によれば、障害物の後方には乱流が形成され、この部分に投入された合金類或いは処理剤は溶銑と直ちに混合するとしている。 For example, in Patent Document 1, when adding a component regulator to hot metal during rotary stirring by an impeller, the hot metal is mechanically stirred to form a hot metal flow, and an obstacle is provided in this flow. A method has been proposed in which a component modifier is added to the turbulent flow induced behind the obstacle. According to Patent Document 1, a turbulent flow is formed behind the obstacle, and the alloys or processing agent introduced into this portion are immediately mixed with the molten iron.
また、特許文献２には、インペラーによる機械攪拌式脱硫法において、攪拌強度を高めるべく、インペラーを精錬容器の中心に対して偏心させた状態で回転させる方法が提案されている。特許文献２によれば、溶銑の攪拌が乱れて乱流となり、脱硫効率が向上するとしている。 Patent Document 2 proposes a method in which the impeller is rotated in an eccentric state with respect to the center of the refining vessel in order to increase the stirring strength in the mechanical stirring type desulfurization method using the impeller. According to Patent Document 2, the stirring of the hot metal is disturbed to form a turbulent flow, and the desulfurization efficiency is improved.
しかしながら、上記従来技術には以下の問題点がある。 However, the above prior art has the following problems.
即ち、特許文献１では、邪魔板などの障害物を設置することで溶銑の流れを乱すことはできるものの、旋回する溶銑の多大な力が障害物に負荷され、障害物の寿命は極めて短く、場合によっては数回の脱硫処理で障害物そのものが消失してしまうという問題がある。つまり、障害物に関わるコストが嵩み、却って脱硫処理コストを増大させる恐れがある。 That is, in Patent Document 1, although the flow of hot metal can be disturbed by installing an obstacle such as a baffle plate, a great force of swirling hot metal is loaded on the obstacle, and the lifetime of the obstacle is extremely short. In some cases, the obstacle itself disappears after several desulfurization treatments. In other words, the cost associated with the obstacle increases, and there is a risk that the desulfurization processing cost will increase.
特許文献２では、インペラーの位置を一定の偏心した位置に合わせることが困難であり、偏心位置の違いによって脱硫効率が変動し、脱硫処理の安定性を欠くという問題がある。また、偏心した側の精錬容器の内張り耐火物の溶損量が、それ以外の部位の内張り耐火物の溶損量に比べて多くなり、精錬容器の寿命を劣化させるという問題もある。 In Patent Document 2, it is difficult to adjust the position of the impeller to a certain eccentric position, and there is a problem that the desulfurization efficiency varies due to the difference in the eccentric position and lacks the stability of the desulfurization process. Moreover, the amount of erosion of the lining refractory in the eccentric smelting vessel is larger than the amount of refractory lining refractory in other parts, and there is a problem that the life of the smelting vessel is deteriorated.
このように、上記の従来技術は設備寿命や安定性などに課題があり、工業的規模での工程的な運用に至ったとの報告はなされていない。 As described above, the above prior art has problems in equipment life and stability, and it has not been reported that the process has been operated on an industrial scale.
本発明は上記事情に鑑みてなされたもので、その目的とするところは、機械攪拌式脱硫装置を用いて溶銑を脱硫処理するにあたり、添加した脱硫剤を溶銑中に効率良く分散することができ、溶銑を従来に比べて高い脱硫率で脱硫処理することのできる、溶銑の脱硫処理用精錬容器及び脱硫処理方法を提供することである。 The present invention has been made in view of the above circumstances, and an object of the present invention is to efficiently disperse the added desulfurizing agent in the hot metal when desulfurizing the hot metal using a mechanical stirring type desulfurization apparatus. An object of the present invention is to provide a hot metal desulfurization refining vessel and a desulfurization processing method capable of desulfurizing hot metal at a higher desulfurization rate than before.
上記課題を解決するための第１の発明に係る溶銑の脱硫処理用精錬容器は、内部に収容した溶銑を機械攪拌式脱硫装置で脱硫処理するための鍋型精錬容器であって、底部の内面形状が該精錬容器の中心軸に対して軸対称とはならないように、底部に施工される耐火物の施工厚みが施工箇所に応じて異なることを特徴とするものである。 A refining vessel for desulfurization treatment of hot metal according to the first invention for solving the above-mentioned problem is a pan-type refining vessel for desulfurization treatment of hot metal contained therein with a mechanical stirring desulfurization apparatus, and an inner surface of the bottom portion The construction thickness of the refractory constructed on the bottom differs depending on the construction location so that the shape is not axisymmetric with respect to the central axis of the smelting vessel.
第２の発明に係る溶銑の脱硫処理用精錬容器は、第１の発明において、前記鍋型精錬容器は、底部の外殻が下方に向かって凸状の曲面であり、且つ、それぞれ底部を２分割し、底部の中心位置を通って直行する２本の直線と平行な方向に成形煉瓦がワーク煉瓦として施工された精錬容器であって、前記２本の直線のうちの何れか一方の直線を境として、底部の片側の１／２の範囲は、厚みが一定の成形煉瓦がワーク煉瓦として施工され、底部の反対側の１／２の範囲は、前記厚みが一定の成形煉瓦よりも厚みが大きく、且つ、前記直線から離れるに伴って厚みの大きくなる成形煉瓦がワーク煉瓦として施工された鍋型精錬容器であることを特徴とするものである。 The refining vessel for desulfurization treatment of hot metal according to the second invention is the refining vessel for desulfurization treatment of hot metal according to the first invention, wherein the pot-type refining vessel is a curved surface having a convex outer shell at the bottom and 2 bottom portions respectively. A refining vessel in which a formed brick is constructed as a work brick in a direction parallel to two straight lines that are divided and go straight through the center of the bottom, and one of the two straight lines is As a boundary, in the range of 1/2 on one side of the bottom, a molded brick with a constant thickness is constructed as a work brick, and in the range of 1/2 on the opposite side of the bottom, the thickness is larger than that of the molded brick with a constant thickness. It is a pan-type smelting vessel in which the molded brick that is large and increases in thickness as it moves away from the straight line is constructed as a work brick.
第３の発明に係る溶銑の脱硫処理用精錬容器は、第１の発明において、前記鍋型精錬容器は、底部外殻が下方に向かって凸状の曲面であり、且つ、底部の中心位置を中心として同心円の環状に成形煉瓦がワーク煉瓦として施工された精錬容器であって、少なくとも底部の中心位置から底部内面半径の１／２を超えた外周側では、底部の中心位置を通って底部を２分割する直線を境として、底部の片側の１／２の範囲は、厚みが一定の成形煉瓦がワーク煉瓦として施工され、底部の反対側の１／２の範囲は、前記厚みが一定の成形煉瓦よりも厚みが大きく、且つ、前記直線から離れるに伴って厚みの大きくなる成形煉瓦がワーク煉瓦として施工された鍋型精錬容器であることを特徴とするものである。 The refining vessel for desulfurization treatment of hot metal according to the third invention is the refining vessel for desulfurization treatment of hot metal according to the first invention, wherein the pot-type refining vessel is a curved surface whose bottom outer shell is convex downward and has a center position at the bottom. A refining vessel in which a shaped brick is constructed as a work brick in the shape of a concentric circle as the center, and at least on the outer peripheral side exceeding the half inner radius of the bottom from the center position of the bottom, the bottom is passed through the center of the bottom. With a straight line dividing into two as a boundary, a half of the range on one side of the bottom is formed as a work brick with a fixed thickness, and a half of the range on the opposite side of the bottom is formed with a constant thickness. The molded brick, which has a thickness greater than that of the brick and increases with increasing distance from the straight line, is a pan-type smelting container constructed as a work brick.
第４の発明に係る溶銑の脱硫処理方法は、内部に耐火物が施工された、ほぼ円形平断面の鍋型精錬容器に収容された溶銑に、前記精錬容器のほぼ中心位置でインペラーを浸漬させ、且つ該インペラーの回転軸をほぼ鉛直にして溶銑中で回転させ、溶銑上に添加された脱硫剤と溶銑とを攪拌して溶銑を脱硫処理するにあたり、前記精錬容器として、その底部の内面形状が該精錬容器の中心軸に対して軸対称ではない鍋型精錬容器を用いることを特徴とするものである。 According to a fourth aspect of the present invention, there is provided a hot metal desulfurization treatment method in which an impeller is immersed at a substantially central position of a smelting vessel in a hot metal housed in a pan-type smelting vessel having a substantially circular flat cross section. In addition, when the desulfurizing agent and hot metal added to the hot metal are agitated and desulfurized by rotating the impeller at a substantially vertical rotation axis in the hot metal, the inner shape of the bottom of the refining vessel is used. However, a pan-type refining vessel that is not axially symmetric with respect to the central axis of the refining vessel is used.
第５の発明に係る溶銑の脱硫処理方法は、第４の発明において、前記鍋型精錬容器は、第１ないし第３の発明の何れか１つに記載の脱硫処理用精錬容器であることを特徴とするものである。 According to a fifth aspect of the present invention, there is provided the hot metal desulfurization treatment method according to the fourth aspect, wherein the pan-type refining vessel is the refining vessel for desulfurization treatment according to any one of the first to third inventions. It is a feature.
第６の発明に係る溶銑の脱硫処理方法は、第４の発明において、前記精錬容器として、底部外殻が下方に向かって凸状の曲面である鍋型精錬容器であって、底部内面の約１／２の範囲が水平面に対して傾斜する平坦状の１つの面となり、且つ、残りの範囲が下方に向かって凸状の曲面となるように、耐火物が施工された鍋型精錬容器を用いることを特徴とするものである。 A hot metal desulfurization treatment method according to a sixth aspect of the present invention is the hot metal desulfurization treatment method according to the fourth aspect of the present invention, wherein the refining vessel is a pan-type refining vessel whose bottom outer shell is a curved surface that protrudes downward. A pot-type smelting vessel in which refractories are constructed so that one half of the flat surface is inclined with respect to the horizontal plane, and the remaining range is a convex curved surface downward. It is characterized by using.
第７の発明に係る溶銑の脱硫処理方法は、第６の発明において、前記底部の平坦状の１つの面は、前記鍋型精錬容器の鉛直方向に直線状の側壁鉄皮外面の下端位置と凸状の曲面である底部鉄皮外面の中心位置とを結ぶ直線が水平面に対して傾斜する角度に対して、更に、３°以上１０°以下の範囲で傾斜していることを特徴とするものである。 According to a seventh aspect of the present invention, there is provided a hot metal desulfurization treatment method according to the sixth aspect of the invention, wherein one flat surface of the bottom portion has a lower end position of an outer surface of the side wall that is linear in the vertical direction of the pot-type refining vessel. A straight line connecting the center position of the outer surface of the bottom iron skin, which is a convex curved surface, is further inclined within a range of 3 ° to 10 ° with respect to an angle inclined with respect to the horizontal plane. It is.
第８の発明に係る溶銑の脱硫処理方法は、第４の発明において、前記精錬容器として、その底部の内面全体が、水平面に対して傾斜する平坦状の１つの面となるように、耐火物が施工された鍋型精錬容器を用いることを特徴とするものである。 The hot metal desulfurization treatment method according to an eighth invention is the refractory according to the fourth invention, wherein the entire inner surface of the bottom portion of the smelting vessel is a flat surface inclined with respect to a horizontal plane. It is characterized by using a pot-type smelting vessel in which is constructed.
第９の発明に係る溶銑の脱硫処理方法は、第８の発明において、前記底部の平坦状の１つの面は、水平面に対して３°以上１０°以下の範囲で傾斜していることを特徴とするものである。 The hot metal desulfurization treatment method according to the ninth invention is characterized in that, in the eighth invention, one flat surface of the bottom portion is inclined in a range of 3 ° to 10 ° with respect to a horizontal plane. It is what.
本発明によれば、機械攪拌式脱硫装置を用いて溶銑を脱硫処理する際に、溶銑を収容する鍋型精錬容器として、その底部の内面形状が該精錬容器の中心軸に対して軸対称ではない鍋型精錬容器を用いるので、インペラーの回転によって生成する渦流が偏心して乱れ、溶銑の攪拌が強化され、溶銑上に添加した脱硫剤と溶銑との攪拌・混合が向上して脱硫剤の溶銑中への分散が促進され、高い脱硫率での脱硫処理が実現される。その結果、脱硫剤の削減などにより製造コストが低減されるのみならず、脱硫スラグ発生量の減少に伴う廃棄物削減により環境への影響が緩和されるなど、顕著な効果がもたらされる。 According to the present invention, when the hot metal is desulfurized using the mechanical stirring type desulfurization apparatus, the shape of the inner surface of the bottom portion of the hot metal is not symmetrical with respect to the central axis of the refining vessel. Since no hot pot-type smelting vessel is used, the vortex generated by the impeller rotation is decentered and turbulent, stirring of the hot metal is strengthened, and the stirring and mixing of the desulfurizing agent and hot metal added to the hot metal is improved. Dispersion into the inside is promoted, and desulfurization treatment at a high desulfurization rate is realized. As a result, not only the manufacturing cost is reduced by reducing the desulfurizing agent, but also the remarkable effect is brought about such as the environmental impact is mitigated by reducing the waste due to the reduction in the amount of desulfurized slag.
以下、本発明を詳細に説明する。 Hereinafter, the present invention will be described in detail.
本発明者らは、機械攪拌式脱硫法において脱硫剤の溶銑中への分散を促進させる方法について検討した。従来の知見から、インペラーの回転攪拌時に生成される渦流の形状を何らかの方法で乱すことで、脱硫剤の巻き込みが促進されることは分かっているが、前述したように、従来技術には工程的な通常運用には問題があった。そこで、本発明者らは、溶銑を収容する精錬容器そのものに改善を施すことで渦形状を乱すことができれば、邪魔板のような短寿命で終わることもなく、また、浸漬位置の偏心のように安定性を欠くこともなくなるのではと考えた。このような考えのもと、本発明者らは、渦形状を乱すための容器形状について検討した。 The present inventors examined a method for promoting the dispersion of the desulfurizing agent in the hot metal in the mechanical stirring type desulfurization method. From the conventional knowledge, it is known that the entrainment of the desulfurization agent is promoted by disturbing the shape of the vortex generated during the rotating stirring of the impeller by some method. There was a problem with normal operation. Therefore, if the vortex shape can be disturbed by improving the smelting vessel itself that contains the hot metal, the present inventors do not end with a short life like a baffle plate, and also the eccentricity of the immersion position. I thought that it would no longer lack stability. Based on such an idea, the present inventors examined a container shape for disturbing the vortex shape.
精錬容器形状の検討にあたっては、機械攪拌式脱硫法における脱硫剤の溶銑中への分散挙動を可視評価するために広く採り入れられている水モデル実験装置を用いて実験した。つまり、実機精錬容器を模擬したアクリル製容器に水を入れ、アクリル製インペラーを水中に浸漬させて回転攪拌を行いつつ、容器上方から擬似脱硫剤を添加した。擬似脱硫剤添加後の水中の状況を高速度カメラを用いて撮影し、水中に進入・分散している擬似脱硫剤の個数を数えて評価した。 In examining the shape of the refining vessel, experiments were conducted using a water model experimental apparatus widely adopted to visually evaluate the dispersion behavior of the desulfurizing agent in the molten iron in the mechanical stirring desulfurization method. That is, water was put into an acrylic container simulating an actual machine refining container, and a pseudo desulfurizing agent was added from above the container while rotating and stirring the acrylic impeller in water. The situation in water after the addition of the pseudo-desulfurizing agent was photographed using a high-speed camera, and the number of pseudo-desulfurizing agents that entered and dispersed in the water was counted and evaluated.
このような評価検討を行った結果、容器の底部を水平面に対して傾斜させた平面とすることで、インペラーの回転により生成される渦流が偏心して、擬似脱硫剤の巻き込みが促進され、擬似脱硫剤の巻き込みは、邪魔板を設置した場合やインペラーの浸漬位置を偏心させた場合と同等になることを確認した。 As a result of such an evaluation study, by setting the bottom of the container to a plane inclined with respect to the horizontal plane, the vortex generated by the rotation of the impeller is decentered and the entrainment of the pseudo desulfurization agent is promoted, and the pseudo desulfurization is performed. It was confirmed that the entrainment of the agent was the same as when the baffle plate was installed or the impeller was immersed in an eccentric position.
図１に、水モデル実験で実施した４種類の試験条件の概要及び試験結果を示す。４種類の試験条件とは、図１に示すように、（１）水平面と平行な平面を底部とする容器の中心位置にインペラーを設置した場合（「通常攪拌」と称す）、（２）通常攪拌の条件下で更に容器の側壁に邪魔板を設置した場合（「邪魔板攪拌」と称す）、（３）水平面と平行な平面を底部とする容器の中心位置とは偏心させてインペラーを設置した場合（「偏心攪拌」と称す）、及び、（４）水平面に対して傾斜した平面を底部とする容器の中心位置にインペラーを設置した場合（「底部勾配攪拌」と称す）の４水準である。 FIG. 1 shows an outline and test results of four types of test conditions performed in the water model experiment. As shown in FIG. 1, the four types of test conditions are as follows: (1) When the impeller is installed at the center position of the container having a plane parallel to the horizontal plane as the bottom (referred to as “normal stirring”), (2) Normal When a baffle plate is further installed on the side wall of the container under stirring conditions (referred to as “baffle plate agitation”), (3) the impeller is installed eccentrically from the central position of the container with a plane parallel to the horizontal plane as the bottom. (4) when the impeller is installed at the center position of the container having a plane inclined with respect to the horizontal plane as the bottom (referred to as “bottom gradient agitation”). is there.
回転するインペラーにより生成する渦形状は、「通常攪拌」ではインペラーの回転軸を中心に軸対称の渦が形成されたのに対し、「邪魔板攪拌」、「偏心攪拌」及び「底部勾配攪拌」では、何れも生成される渦流がインペラーの回転軸に対して対称ではなくなり、偏心した渦流が形成され、渦流が乱れる様子が観察された。また、擬似脱硫剤の巻き込み割合についても、「通常攪拌」では添加した擬似脱硫剤の１０％であったのに対し、「邪魔板攪拌」、「偏心攪拌」及び「底部勾配攪拌」では添加した擬似脱硫剤の２５％が巻き込まれることが確認できた。尚、擬似脱硫剤の巻き込み割合は、「（水中に巻き込まれた擬似脱硫剤の個数）×１００／（添加した全擬似脱硫剤の個数）」で求めたものである。 The vortex shape generated by the rotating impeller is symmetric with respect to the rotation axis of the impeller in “normal stirring”, whereas “baffle stirring”, “eccentric stirring” and “bottom gradient stirring”. In either case, the generated vortex was not symmetrical with respect to the impeller rotation axis, and an eccentric vortex was formed, and the vortex was observed to be disturbed. Further, the entrainment ratio of the pseudo-desulfurization agent was 10% of the added pseudo-desulfurization agent in the “normal stirring”, whereas it was added in the “baffle plate stirring”, “eccentric stirring” and “bottom gradient stirring”. It was confirmed that 25% of the pseudo-desulfurization agent was involved. In addition, the entrainment ratio of the pseudo desulfurizing agent is obtained by “(number of pseudo desulfurizing agents entrained in water) × 100 / (number of all pseudo desulfurizing agents added)”.
このように水モデル実験においては、精錬容器の底部に傾斜勾配を設けることで渦流を乱すことができ、脱硫剤の巻き込みを増加させることが確認できたので、実機での可能性を確認するべく、実機試験を実施した。具体的には、精錬容器としてほぼ円形平断面の溶銑鍋を用い、溶銑鍋の底部全体の形状を耐火物の施工によって水平面に対して傾斜させた平坦状の面に変更し、機械攪拌式脱硫法での精錬容器に供した。その結果、実機の機械攪拌式脱硫装置においても、溶銑鍋の底部全体の形状を水平面に対して傾斜させた平坦状の面として、インペラーを精錬容器のほぼ中心位置でほぼ鉛直にして回転することで、脱硫効率が大幅に向上することが確認できた。これは、水モデル実験で確認されたように、実操業においても添加した脱硫剤の溶銑中への分散が促進され、脱硫反応に寄与し得る脱硫剤の割合が増加し、脱硫効率が向上したためである。 In this way, in the water model experiment, it was confirmed that the vortex flow could be disturbed by providing an inclined gradient at the bottom of the refining vessel, and it was confirmed that the entrainment of the desulfurization agent was increased. An actual machine test was conducted. Specifically, a hot metal ladle with a substantially circular flat cross section is used as the refining vessel, and the shape of the entire bottom of the hot metal ladle is changed to a flat surface inclined with respect to the horizontal surface by the construction of refractory, and mechanical stirring desulfurization is performed. Used for refining vessel by law. As a result, even in the actual mechanical stirring type desulfurization apparatus, the shape of the entire bottom of the hot metal ladle is a flat surface inclined with respect to the horizontal plane, and the impeller is rotated substantially vertically at the substantially center position of the smelting vessel. It was confirmed that the desulfurization efficiency was greatly improved. This is because, as confirmed in the water model experiment, the dispersion of the desulfurizing agent added in the actual operation was promoted in the molten iron, the proportion of the desulfurizing agent that can contribute to the desulfurization reaction increased, and the desulfurization efficiency was improved. It is.
尚、実機溶銑鍋の底部は耐火物で施工されるので、「平面」に施工しようとしても幾何学的な平面を得ることは極めて困難であり、特に成形煉瓦で施工した場合には、細かい凹凸を有する面として施工されるが、全体的な形状は平坦状の１つの面と見て差し支えないので、ここでは、施工された耐火物により形成される上記形状の面を「平坦状の１つの面」と定義している。また、溶銑鍋の平断面は設計時には円形であるが、使用中に熱により変形し楕円形状になり、この変形した形状も含めて、「ほぼ円形平断面」と称している。また、インペラーの設置位置を、「精錬容器のほぼ中心位置」と表示しているが、インペラーの設置位置は目視で行われることが多く、本発明においては「目視による精錬容器の中心位置」にインペラーを設置すればよく、「精錬容器のほぼ中心位置」とは、幾何学的な中心位置ではなく、「目視による精錬容器の中心位置」という意味である。また更に、「インペラーをほぼ鉛直にして回転する」とは、幾何学的な鉛直方向であればもちろん好ましいが、鉛直方向に設計されても偏心などにより使用中に幾何学的な鉛直方向からずれることがあり、これを含むという意味である。 In addition, since the bottom of the actual hot metal ladle is constructed with refractory material, it is extremely difficult to obtain a geometrical plane even when trying to construct it on a “planar”, especially when it is constructed with molded bricks. However, since the overall shape can be viewed as a flat surface, the surface of the above shape formed by the applied refractory is referred to as “a flat surface. Is defined as "face". The flat cross section of the hot metal ladle is circular at the time of design, but is deformed by heat during use to become an elliptical shape, and this deformed shape is also referred to as an “almost circular flat cross section”. In addition, although the installation position of the impeller is indicated as “substantially the center position of the refining vessel”, the installation position of the impeller is often visually observed, and in the present invention, the “center position of the refining vessel” is indicated. An impeller may be installed, and the “substantially center position of the refining vessel” means “the center position of the refining vessel by visual observation”, not the geometric center position. Furthermore, “rotating with the impeller substantially vertical” is of course preferably in the geometrical vertical direction, but even if designed in the vertical direction, it deviates from the geometrical vertical direction during use due to eccentricity or the like. It means that it is included.
また、精錬容器底部の半分程度を「平坦状の１つの面」とした場合も、底部全体を傾斜させた場合と同等の脱硫率向上効果が得られることが確認できた。精錬容器の底部の半分程度を「平坦状の１つの面」とする場合には、既設の精錬容器であっても、改造のための耐火物の施工量が底部全体を平坦状にする場合に比べて少なくなることから望ましい。 In addition, it was confirmed that even when about half of the bottom of the refining vessel was made “one flat surface”, the same desulfurization rate improvement effect was obtained as when the entire bottom was inclined. When about half of the bottom of the smelting vessel is set to “one flat surface”, even if it is an existing smelting vessel, the amount of refractory construction for remodeling is to make the entire bottom flat. This is desirable because it is less.
更に、本発明者らは、容器底部の「平坦状の１つの面」の傾斜勾配の最適化範囲についても検討した。その結果、底部の全体が平坦状の精錬容器の場合は、「平坦状の１つの面」の水平面に対する傾斜角度は３°以上１０°以下の範囲が好ましいことが分かった。水平面に対する傾斜角度が３°未満では生成する渦流の偏心程度が少なく、脱硫効率の改善効率が少なくなり、一方、水平面に対する傾斜角度が１０°を越えると脱硫効率の改善効果は飽和してそれ以上の改善効果は得られず、逆に、精錬容器の収容容量が減少して生産性が低下するなどの問題が生ずる。 Furthermore, the present inventors also examined the optimization range of the inclination gradient of “one flat surface” at the bottom of the container. As a result, it was found that when the entire bottom portion is a flat refining vessel, the inclination angle of “one flat surface” with respect to the horizontal plane is preferably in the range of 3 ° to 10 °. If the tilt angle with respect to the horizontal plane is less than 3 °, the degree of eccentricity of the generated vortex is small and the desulfurization efficiency improvement efficiency decreases. On the other hand, if the tilt angle with respect to the horizontal plane exceeds 10 °, the desulfurization efficiency improvement effect is saturated and beyond. However, there is a problem that the capacity of the refining vessel is reduced and productivity is lowered.
また、溶銑鍋のような底部の外殻形状が下方に向かって凸状の曲面である鍋型精錬容器の場合には、曲面形状の底部内面の勾配は外殻と同様に水平ではない。底部に施工される耐火物は外殻形状に添って施工されることから、この曲面形状の底部の勾配を、「当該鍋型精錬容器の鉛直方向に直線形状である側壁鉄皮の下端位置と、凸状の曲面形状である底部鉄皮の中心位置とを結ぶ直線が、水平面に対して傾斜する角度（この角度を「角度θs」と表示する）」と定義すると、「平坦状の１つの面」は、前記直線が水平面に対して傾斜する角度θsよりも更に３°以上１０°以下傾斜することが好ましいことが分かった。３°未満では軸対称からの変位が小さいので生成する渦流の偏心程度が少なく、一方、１０°を超えると脱硫効率の改善効果は飽和してそれ以上の改善効果は得られず、逆に、精錬容器の収容容量が減少して生産性が低下するなどの問題が生ずる。 In addition, in the case of a pot-type smelting vessel in which the shape of the outer shell of the bottom, such as a hot metal ladle, is a curved surface that is convex downward, the gradient of the inner surface of the bottom of the curved shape is not horizontal as with the outer shell. Since the refractory to be constructed at the bottom is constructed according to the outer shell shape, the slope of the bottom of this curved shape is defined as `` the lower end position of the side wall iron skin that is linear in the vertical direction of the pot-type smelting vessel. When the angle connecting the straight line connecting the center position of the bottom iron shell, which is a convex curved shape, is inclined with respect to the horizontal plane (this angle is expressed as “angle θs”), It was found that the “plane” is preferably inclined at 3 ° or more and 10 ° or less than the angle θs at which the straight line is inclined with respect to the horizontal plane. If the angle is less than 3 °, the displacement from the axial symmetry is small, so the degree of eccentricity of the generated vortex is small. On the other hand, if it exceeds 10 °, the improvement effect of the desulfurization efficiency is saturated and no further improvement effect can be obtained. Problems such as a reduction in productivity due to a decrease in the capacity of the refining vessel occur.
図２に、底部の外殻形状が下方に向かって凸状の曲面である溶銑鍋２を精錬容器として使用した場合に、溶銑鍋２の底部に耐火物を施工し、溶銑鍋底部の全体を、水平面に対して傾斜角度θで傾斜させた、平坦状の１つの面とした例（図２（Ａ））と、溶銑鍋底部の約半分を底部傾斜角度θsよりも更に傾斜角度θで傾斜させた、平坦状の１つの面とした例（図２（Ｂ））とを示す。図２（Ｂ）の直線Ｘ−Ｘ’が、溶銑鍋２の鉛直方向に直線形状である側壁鉄皮の下端位置と、凸状の曲面形状である底部鉄皮の中心位置と、を結ぶ直線である。 In FIG. 2, when using the hot metal ladle 2 whose bottom shell shape is a convex curved surface downward as a smelting vessel, a refractory is applied to the bottom of the hot metal ladle 2 and the entire bottom of the hot metal ladle is An example of a flat surface inclined at an inclination angle θ with respect to the horizontal plane (FIG. 2A) and about half of the bottom of the hot metal ladle at an inclination angle θ further than the bottom inclination angle θs The example (FIG. 2 (B)) made into one flat surface made is shown. A straight line XX ′ in FIG. 2B connects the lower end position of the side wall iron skin that is linear in the vertical direction of the hot metal ladle 2 and the center position of the bottom iron skin that is a convex curved surface shape. It is.
また更に、詳細に検討した結果、精錬容器底部の全体或いは半分程度を傾斜した「平坦状の１つの面」とするだけでなく、インペラーの回転により生成される渦流が、インペラーの回転軸に対して対称ではなくなり、偏心した渦流が形成されるような形状とすれば、脱硫剤の分散が促進されることを確認した。 In addition, as a result of detailed examination, not only the whole or half of the bottom of the smelting vessel is made to be a “flat one surface”, but also the vortex generated by the rotation of the impeller is not affected by the rotation axis of the impeller. It was confirmed that the dispersion of the desulfurizing agent was promoted if the shape was not symmetrical and formed an eccentric vortex.
即ち、溶銑鍋のような底部の外殻形状が下方に向かって凸状の曲面である精錬容器において、底部の耐火物の施工厚みを変化させ、底部全体の内面形状は曲面ではあるが曲率の異なる曲面とすることで、渦流がインペラーの回転軸に対して対称ではなくなり、偏心した渦流が形成されて、脱硫剤の分散が促進されることを確認した。 That is, in a smelting vessel where the outer shell shape of the bottom, such as a hot metal ladle, is a curved surface that is convex downward, the construction thickness of the refractory at the bottom is changed, and the inner shape of the entire bottom is curved but the curvature is It was confirmed that by using different curved surfaces, the vortex was not symmetrical with respect to the impeller rotation axis, an eccentric vortex was formed, and the dispersion of the desulfurizing agent was promoted.
図３及び図４は、底部の外殻形状が下方に向かって凸状の曲面である精錬容器の底部に施工されるワーク煉瓦の厚みを変化させ、底部全体の内面形状は曲面ではあるが、底部の１／２の範囲における曲率を他の１／２の範囲での曲率とは変化させた例を示す図であり、図３は精錬容器の底部全体のワーク煉瓦の施工方法を示す平面図、図４は図３のＸ−Ｘ’矢視による断面図である。 3 and 4, the thickness of the work brick applied to the bottom of the smelting vessel whose outer shell shape at the bottom is a curved surface convex downward is changed, and the inner shape of the entire bottom is a curved surface, It is a figure which shows the example which changed the curvature in the 1/2 range of the bottom part with the curvature in the other 1/2 range, and FIG. 3 is a top view which shows the construction method of the work brick of the whole bottom part of a smelting vessel 4 is a cross-sectional view taken along the line XX ′ of FIG.
図３及び図４に示すように、精錬容器１３の外殻を形成する鉄皮１４の内面側に、成形煉瓦からなる永久煉瓦１５が施工され、その内面側に成形煉瓦からなるワーク煉瓦１６が施工されている。この場合、底部には３層の永久煉瓦１５が施工されているが、永久煉瓦１５は３層に限るものではなく１層以上であれば構わない。また、底部において、永久煉瓦１５は同一の厚みで施工されている。 As shown in FIGS. 3 and 4, a permanent brick 15 made of molded brick is constructed on the inner surface side of the iron skin 14 that forms the outer shell of the refining vessel 13, and a work brick 16 made of molded brick is formed on the inner surface side thereof. It is being constructed. In this case, the three-layer permanent brick 15 is constructed at the bottom, but the permanent brick 15 is not limited to three layers and may be one or more layers. Moreover, the permanent brick 15 is constructed with the same thickness at the bottom.
この永久煉瓦１５の内面側にワーク煉瓦１６が、精錬容器１３の底部を２分割し、底部の中心位置を通って直行する２本の直線（図３では紙面の上下方向の中心線及び左右方向の中心線）と平行な方向に規則的に施工されている。そして、上下方向の中心線よりも右側のワーク煉瓦１６は厚みが１６０ｍｍの一定であり、一方、上下方向の中心線よりも左側のワーク煉瓦１６は、厚みが２３０ｍｍ、２８０ｍｍ、３２０ｍｍの３種類であり、しかも、上下方向の中心線から離れるに伴って厚みの大きいワーク煉瓦１６が施工されている。即ち、ワーク煉瓦１６の稼働面（溶銑との接触面）の曲率が底部の他の１／２の範囲とは異なり、且つ、更に曲率の異なる範囲での曲率が徐々に変化するように、ワーク煉瓦１６が施工されている。 The work brick 16 divides the bottom part of the refining vessel 13 into two parts on the inner surface side of the permanent brick 15 and goes straight through the center position of the bottom part (in FIG. 3, the center line in the vertical direction and the horizontal direction in FIG. 3). It is constructed regularly in a direction parallel to the center line of The work brick 16 on the right side of the center line in the vertical direction has a constant thickness of 160 mm, while the work brick 16 on the left side of the center line in the vertical direction has three types of thicknesses of 230 mm, 280 mm, and 320 mm. In addition, a thick work brick 16 is constructed as the distance from the vertical center line increases. In other words, the work brick 16 has a working surface (contact surface with the hot metal) having a curvature different from the other half of the bottom and further changing the curvature in a different curvature range. A brick 16 is constructed.
この精錬容器１３を用いて溶銑を脱硫処理した場合には、インペラーの回転により生成される渦流が、インペラーの回転軸に対して対称ではなくなり、偏心して乱れた渦流が形成され、脱硫剤の分散が促進される。 When the hot metal is desulfurized using the refining vessel 13, the vortex generated by the rotation of the impeller is not symmetric with respect to the rotation axis of the impeller, and an eccentric and turbulent vortex is formed. Is promoted.
また、図５及び図６は、底部の外殻形状が下方に向かって凸状の曲面である精錬容器の底部ワーク煉瓦の厚みを変化させ、底部全体の内面形状は曲面ではあるが、底部の曲率を変化させた他の例を示す図であり、図５は精錬容器の底部全体のワーク煉瓦の施工方法を示す平面図、図６は図５のＹ−Ｙ’矢視による断面図である。 5 and 6 change the thickness of the bottom work brick of the smelting vessel in which the outer shell shape of the bottom portion is a curved surface convex downward, and the inner shape of the entire bottom portion is a curved surface. It is a figure which shows the other example which changed the curvature, FIG. 5 is a top view which shows the construction method of the work brick of the whole bottom part of a smelting container, FIG. 6 is sectional drawing by the YY 'arrow of FIG. .
図５及び図６に示すように、精錬容器１３Ａの外殻を形成する鉄皮１４の内面側に、成形煉瓦からなる永久煉瓦１５が施工され、その内面側に成形煉瓦からなるワーク煉瓦１７が施工されている。この場合、底部には３層の永久煉瓦１５が施工されているが、永久煉瓦１５は３層に限るものではなく１層以上であれば構わない。また、底部において、永久煉瓦１５は同一の厚みで施工されている。 As shown in FIGS. 5 and 6, a permanent brick 15 made of molded brick is constructed on the inner surface side of the iron skin 14 forming the outer shell of the refining vessel 13A, and a work brick 17 made of molded brick is formed on the inner surface side. It is being constructed. In this case, the three-layer permanent brick 15 is constructed at the bottom, but the permanent brick 15 is not limited to three layers and may be one or more layers. Moreover, the permanent brick 15 is constructed with the same thickness at the bottom.
この永久煉瓦１５の内面側にワーク煉瓦１７が、底部の中心位置を中心として同心円の環状に、円周方向に放射状に並んで施工されている。そして、少なくとも底部の中心位置から底部内面半径の１／２を超えた外周側では、同心円の円環に、底部の中心位置を通って底部を２分割する直線（図５では紙面の上下方向の中心線）を境として、底部の片側の１／２の範囲は、厚みが１６０ｍｍの一定であるワーク煉瓦１７が施工され、一方、底部の反対側の１／２の範囲は、厚みが２３０ｍｍ、２８０ｍｍ、３２０ｍｍの３種類のワーク煉瓦１７のうちの少なくとも２種類以上のワーク煉瓦１７が、前記上下方向の中心線から離れるに伴って厚みが大きくなるように施工されている。即ち、底部のワーク煉瓦１７の稼働面の曲率が位置によって異なり、且つ、その曲率が徐々に変化するように、ワーク煉瓦１７が施工されている。 Work bricks 17 are constructed on the inner surface side of the permanent bricks 15 in a concentric annular shape centering on the center position of the bottom and arranged radially in the circumferential direction. And at least on the outer peripheral side exceeding the bottom inner radius of the bottom from the center position of the bottom, a straight line that divides the bottom into two through the center position of the bottom in a concentric circle (in FIG. With the center line) as a boundary, a half range on one side of the bottom is constructed with a work brick 17 having a constant thickness of 160 mm, while a half range on the opposite side of the bottom is 230 mm in thickness, Of the three types of work bricks 17 of 280 mm and 320 mm, at least two types of work bricks 17 are constructed so as to increase in thickness as they move away from the center line in the vertical direction. That is, the work brick 17 is constructed so that the curvature of the working surface of the bottom work brick 17 varies depending on the position and the curvature gradually changes.
この精錬容器１３Ａを用いて溶銑を脱硫処理した場合には、インペラーの回転により生成される渦流が、インペラーの回転軸に対して対称ではなくなり、偏心して乱れた渦流が形成され、脱硫剤の分散が促進される。 When the hot metal is desulfurized using the refining vessel 13A, the vortex generated by the rotation of the impeller is not symmetrical with respect to the rotation axis of the impeller, and an eccentric and turbulent vortex is formed. Is promoted.
尚、精錬容器１３及び精錬容器１３Ａでは、４種類の厚みのワーク煉瓦を使用しているが、２種類以上であれば、インペラーの回転により生成される渦流に乱れが生ずることを確認しており、ワーク煉瓦の厚みは２種類であっても構わない。また、精錬容器１３及び精錬容器１３Ａでは、ワーク煉瓦が１層であるが２層以上としても構わない。更に、永久煉瓦１５の施工方法は、図３に示すような格子状であっても、また図５に示すような環状であってもどちらでも構わない。 The refining vessel 13 and the refining vessel 13A use four types of work bricks, but if there are two or more types, it has been confirmed that the vortex generated by the rotation of the impeller is disturbed. The thickness of the work brick may be two types. Further, in the refining vessel 13 and the refining vessel 13A, the work brick is one layer, but two or more layers may be used. Furthermore, the construction method of the permanent brick 15 may be either a lattice shape as shown in FIG. 3 or an annular shape as shown in FIG.
このワーク煉瓦の稼働面の曲率を変化させる耐火物施工方法は、精錬容器底部の全体或いは一部を「平坦状の１つの面」とする場合に比較して成形煉瓦の種類を少なくすることができ、施工が容易であるのみならずコスト的にも好ましい。 The refractory construction method that changes the curvature of the working surface of this work brick may reduce the type of the formed brick compared to the case where the entire or part of the bottom of the smelting vessel is made "one flat surface". This is preferable not only because the construction is easy, but also in terms of cost.
このように、精錬容器の底部形状を、精錬容器の中心軸に対して軸対称ではない形状とすれば、インペラーの回転により生成される渦流も自ずと精錬容器の中心軸に対して軸対称ではなくなり、偏心した渦流が形成される。従って、精錬容器の底部形状を、傾斜する面と水平面とが交互に現れ、全体としては傾斜した構造や、一方側から他方側に向けて傾斜した曲面構造などとしても同等の効果を得ることができる。 Thus, if the bottom shape of the smelting vessel is a shape that is not axially symmetric with respect to the central axis of the smelting vessel, the vortex generated by the rotation of the impeller is not naturally symmetric with respect to the central axis of the smelting vessel. An eccentric vortex is formed. Therefore, the bottom shape of the smelting vessel can be obtained as an inclined structure and a curved surface structure that is inclined from one side to the other side as a whole, with inclined surfaces and horizontal surfaces appearing alternately. it can.
本発明は上記知見に基づきなされたもので、本発明に係る溶銑の脱硫処理用精錬容器は、底部の内面形状が該精錬容器の中心軸に対して軸対称とはならないように、底部に施工される耐火物の施工厚みが施工箇所に応じて異なる鍋型精錬容器であり、本発明に係る脱硫処理方法は、内部に耐火物が施工された、ほぼ円形平断面の鍋型精錬容器に収容された溶銑に、前記精錬容器のほぼ中心位置でインペラーを浸漬させ、且つ該インペラーの回転軸をほぼ鉛直にして溶銑中で回転させ、溶銑上に添加された脱硫剤と溶銑とを攪拌して溶銑を脱硫処理するにあたり、前記精錬容器として、その底部形状が該精錬容器の中心軸に対して軸対称ではない鍋型精錬容器を用いることを特徴とする。 The present invention has been made on the basis of the above knowledge, and the refining vessel for desulfurization treatment of hot metal according to the present invention is applied to the bottom so that the inner shape of the bottom is not axisymmetric with respect to the central axis of the refining vessel. The refractory construction thickness varies depending on the construction location, and the desulfurization treatment method according to the present invention is accommodated in a pan-type smelting container having a substantially circular flat cross section in which the refractory is constructed. In the molten iron, the impeller is immersed at a substantially central position of the refining vessel, and the impeller is rotated in the molten iron so that the rotation axis of the impeller is substantially vertical, and the desulfurizing agent and molten iron added on the molten iron are stirred. When the hot metal is desulfurized, a pan-type smelting vessel whose bottom shape is not axisymmetric with respect to the central axis of the smelting vessel is used as the smelting vessel.
本発明の脱硫処理において、使用する脱硫剤としては、生石灰単独、或いは生石灰に滓化促進剤としてホタル石（ＣａＦ2）を混合したものを使用することができる。但し、フッ素の環境への影響を軽減する観点から、ホタル石を含有しない脱硫剤であることが望ましい。その他の脱硫剤としては、ＣａＯ系であれば、消石灰や石灰石を用いることができ、カルシウムカーバイト系やソーダ系、更にはドロマイト系の脱硫剤を使用することもできる。また更に、溶銑脱硫処理において発生する脱硫スラグを回収し、再度脱硫剤としてリサイクル使用することも可能である。 In the desulfurization treatment of the present invention, as the desulfurizing agent to be used, quick lime alone or a mixture of limestone (CaF 2 ) as a hatching accelerator can be used. However, from the viewpoint of reducing the influence of fluorine on the environment, a desulfurization agent containing no fluorite is desirable. As other desulfurizing agents, slaked lime and limestone can be used as long as they are CaO-based, and calcium carbide-based, soda-based, and dolomite-based desulfurizing agents can also be used. Furthermore, it is also possible to collect the desulfurization slag generated in the hot metal desulfurization treatment and recycle it again as a desulfurization agent.
脱硫剤の添加方法は、ホッパー及びシュートなどからなる供給装置を用いて精錬容器内の溶銑上に上置き添加するのが一般的であるが、精錬容器の上方に設けた上吹きランスからＡｒガス或いは窒素ガスなどを搬送用ガスとして、連続的に溶銑浴面に吹き付けて添加する方法であってもよい。 The desulfurizing agent is generally added on top of the hot metal in the refining vessel using a feeding device such as a hopper and a chute, but Ar gas is supplied from the upper blowing lance provided above the refining vessel. Alternatively, a method may be used in which nitrogen gas or the like is added as a carrier gas by spraying continuously on the hot metal bath surface.
また、脱硫反応は雰囲気の酸素ポテンシャルが低いほど促進されるので、脱硫処理時に金属Ａｌ、フェロシリコンなどの金属系脱酸剤やＡｌドロスを精錬容器内に投入することが好ましい。また、溶銑浴面を還元性雰囲気とするために、プロパンガスのような炭化水素系ガスを精錬容器内に供給するようにしてもよい。 Further, since the desulfurization reaction is promoted as the oxygen potential of the atmosphere is lower, it is preferable to introduce a metal deoxidizer such as metal Al or ferrosilicon or Al dross into the refining vessel during the desulfurization treatment. Moreover, in order to make the hot metal bath surface a reducing atmosphere, a hydrocarbon-based gas such as propane gas may be supplied into the refining vessel.
このようにして溶銑を脱硫処理することで、インペラーの回転によって生成される精錬容器内の渦流が偏心して乱れ、溶銑の攪拌が強化され、溶銑上に添加した脱硫剤と溶銑との攪拌・混合が向上して脱硫剤の溶銑中への分散が促進され、高い脱硫率での脱硫処理が実現される。その結果、脱硫剤の削減などにより製造コストが低減されるのみならず、脱硫スラグ発生量の減少に伴う廃棄物削減により環境への影響が緩和されるなど、顕著な効果がもたらされる。 By desulfurizing the hot metal in this way, the vortex flow in the refining vessel generated by the rotation of the impeller is decentered and disturbed, the stirring of the hot metal is strengthened, and the desulfurization agent added on the hot metal is stirred and mixed. This improves the dispersion of the desulfurizing agent in the hot metal and realizes a desulfurization process at a high desulfurization rate. As a result, not only the manufacturing cost is reduced by reducing the desulfurizing agent, but also the remarkable effect is brought about such as the environmental impact is mitigated by reducing the waste due to the reduction in the amount of desulfurized slag.
容量が３００トンの溶銑鍋を用い、通常の溶銑鍋を用いて溶銑鍋の中心位置にインペラーを設置した場合（通常攪拌）、通常攪拌の条件下で更に容器の側壁に邪魔板を設置した場合（邪魔板攪拌）、通常の溶銑鍋を用いて溶銑鍋の中心位置とは偏心させてインペラーを設置した場合（偏心攪拌）、及び、底部の約１／２を水平面に対して傾斜した平面とする溶銑鍋の中心位置にインペラーを設置した場合（底部勾配攪拌）の４水準により溶銑に対して脱硫試験を実施した。尚、溶銑鍋の底部外殻形状は、溶銑鍋の中心軸に対して軸対称な、下方に凸状の曲面で構成されている。上記の底部勾配攪拌が本発明例であり、その他は比較例である。 When using an iron pan with a capacity of 300 tons and installing an impeller at the center position of the hot metal pan using a normal hot metal pan (normal stirring), when installing a baffle plate on the side wall of the container under normal stirring conditions (Baffle plate agitation), when a normal hot metal ladle is used and an impeller is installed eccentrically with the center position of the hot metal ladle (eccentric agitation), and a plane in which about 1/2 of the bottom is inclined with respect to the horizontal plane The desulfurization test was carried out on the hot metal according to the four levels when the impeller was installed at the center position of the hot metal ladle (bottom gradient stirring). In addition, the bottom outer shell shape of the hot metal ladle is configured by a downwardly convex curved surface that is axisymmetric with respect to the central axis of the hot metal ladle. The bottom gradient agitation described above is an example of the present invention, and the others are comparative examples.
図７に、４水準の脱硫試験を実施した機械攪拌式脱硫装置の概略断面図を示す。尚、図７は、通常の溶銑鍋を使用した「通常攪拌」の例を示す図である。 FIG. 7 shows a schematic cross-sectional view of a mechanical stirring desulfurization apparatus that has performed a four-level desulfurization test. In addition, FIG. 7 is a figure which shows the example of "normal stirring" using a normal hot metal ladle.
図７に示すように、機械攪拌式脱硫裝置は、精錬容器である溶銑鍋２に収容された溶銑３に浸漬・埋没し、旋回して溶銑３を攪拌するための耐火物製のインペラー４を備えており、このインペラー４は、昇降装置（図示せず）によってほぼ鉛直方向に昇降し、且つ、回転装置（図示せず）によって軸４ａを回転軸として旋回するようになっている。また、機械攪拌式脱硫裝置には、粒状または粉体状の脱硫剤７を溶銑鍋２に収容された溶銑３の浴面に上置き添加するための投入シュート６、並びに、粉体状の脱硫剤７Ａを溶銑鍋２に収容された溶銑３に向けて搬送用ガスとともに上吹きして添加するための上吹きランス５が設置されている。更に、溶銑鍋２の上方位置には、集塵機（図示せず）に接続する排気ダクト口（図示せず）が備えられ、脱硫処理中に発生するガスやダストが排出されるようになっている。 As shown in FIG. 7, the mechanical stirring type desulfurization apparatus includes a refractory impeller 4 for immersing and burying in a hot metal 3 accommodated in a hot metal ladle 2 which is a refining vessel, and rotating to stir the hot metal 3. The impeller 4 is moved up and down in a substantially vertical direction by an elevating device (not shown) and swiveled around a shaft 4a as a rotating shaft by a rotating device (not shown). In addition, in the mechanical stirring type desulfurization apparatus, a granular or powdered desulfurizing agent 7 is added to the bath surface of the hot metal 3 accommodated in the hot metal ladle 2, and a powder desulfurization is performed. An upper blowing lance 5 is provided for blowing the agent 7A toward the hot metal 3 accommodated in the hot metal ladle 2 and adding it together with the conveying gas. Further, an exhaust duct port (not shown) connected to a dust collector (not shown) is provided at an upper position of the hot metal ladle 2 so that gas and dust generated during the desulfurization process are discharged. .
投入シュート６は、粒状または粉体状の脱硫剤７を収容するホッパー１０と、ホッパー１０から定量切り出すためのロータリーフィーダー１１とからなる供給装置と接続しており、投入シュート６から、粒状または粉体状の脱硫剤７を任意のタイミングで供給できる構造になっている。また、上吹きランス５は、粉体状の脱硫剤７Ａを収容するホッパー８と、ホッパー８から定量切り出すための切出装置９とからなる供給装置と接続しており、上吹きランス５から、窒素ガスやＡｒガスなどの搬送用ガスとともに、粉体状の脱硫剤７Ａを任意のタイミングで供給できる構造になっている。 The input chute 6 is connected to a supply device including a hopper 10 that contains the granular or powdered desulfurization agent 7 and a rotary feeder 11 for quantitatively cutting out from the hopper 10. The body-like desulfurizing agent 7 can be supplied at an arbitrary timing. Further, the upper blowing lance 5 is connected to a supply device including a hopper 8 containing the powdery desulfurizing agent 7A and a cutting device 9 for quantitative cutting out from the hopper 8, Along with a carrier gas such as nitrogen gas or Ar gas, the powdery desulfurizing agent 7A can be supplied at an arbitrary timing.
尚、脱硫剤を上吹きランス５から吹き込むか、投入シュート６から添加するかは、使用する脱硫剤の大きさなどから、適宜選択すればよい。本実施例では、条件をそろえるために投入シュート６から上置き添加した。溶銑鍋２は台車１に搭載されており、台車１の位置を調整することで、インペラー４の位置が決定される。但し、溶銑鍋２は台車１に対して常に一定の位置に搭載されるわけではなく、台車上での搭載位置に多少の余裕代があり、台車１の停車位置を一定に調整しても、インペラー４の位置は多少ではあるが前後左右にずれることになる。 Whether the desulfurizing agent is blown from the top blowing lance 5 or added from the charging chute 6 may be appropriately selected based on the size of the desulfurizing agent to be used. In this example, the addition was carried out from the charging chute 6 in order to adjust the conditions. The hot metal ladle 2 is mounted on the carriage 1, and the position of the impeller 4 is determined by adjusting the position of the carriage 1. However, the hot metal ladle 2 is not always mounted at a fixed position with respect to the carriage 1, and there is some margin in the mounting position on the carriage, and even if the stopping position of the carriage 1 is adjusted to be constant, The position of the impeller 4 is slightly shifted from front to back and from side to side.
通常攪拌を除く、邪魔板攪拌、偏心攪拌及び底部勾配攪拌の３水準のそれぞれの試験において使用した溶銑鍋の形状及びインペラーと溶銑鍋との位置関係を図８に示す。 FIG. 8 shows the shape of the hot metal ladle and the positional relationship between the impeller and the hot metal ladle used in each of the three tests of baffle plate stirring, eccentric stirring, and bottom gradient stirring except for normal stirring.
邪魔板攪拌の場合には、図８（Ａ）に示すように、溶銑鍋の側壁の一箇所に邪魔板１２を設置した。この邪魔板１２は、溶銑鍋の内径（半径）をＤとすると、厚み及び幅ともにＤ／１０とし、高さは溶銑浴の高さ以上とした。溶銑鍋の底部形状は通常の溶銑鍋と同一形状であり、インペラーは溶銑鍋のほぼ中心に配置した。 In the case of baffle plate stirring, as shown in FIG. 8 (A), a baffle plate 12 was installed at one place on the side wall of the hot metal ladle. When the inner diameter (radius) of the hot metal ladle is D, the baffle plate 12 has a thickness and a width of D / 10, and the height is higher than the height of the hot metal bath. The shape of the bottom of the hot metal ladle was the same as that of a normal hot metal ladle, and the impeller was arranged almost at the center of the hot metal ladle.
偏心攪拌の場合には、図８（Ｂ）に示すように、溶銑鍋の内径（半径）をＤとすると、溶銑鍋の中心軸に対してＤ／４だけ偏心した位置にインペラーを配置した。溶銑鍋の底部形状は通常の溶銑鍋と同一形状である。 In the case of eccentric stirring, as shown in FIG. 8 (B), when the inner diameter (radius) of the hot metal ladle is D, the impeller is arranged at a position eccentric by D / 4 with respect to the central axis of the hot metal ladle. The shape of the bottom of the hot metal ladle is the same as that of a normal hot metal ladle.
底部勾配攪拌の場合には、図８（Ｃ）に示すように、溶銑鍋底部の約１／２の耐火物の施工方法を通常とは変えてほぼ平坦状の面とし、且つこの面が底部傾斜角度θsよりも更に傾斜角度度θ＝５°の角度で傾斜するように耐火物を施工した。インペラーは溶銑鍋のほぼ中心に配置した。 In the case of bottom gradient agitation, as shown in FIG. 8C, the construction method of about 1/2 of the refractory material at the bottom of the hot metal pan is changed from a normal one to a substantially flat surface, and this surface is the bottom. The refractory was constructed so as to be inclined at an angle of inclination angle θ = 5 ° further than the inclination angle θs. The impeller was placed almost at the center of the hot metal pan.
そして、化学成分が、Ｃ：３．９〜４．９質量％、Ｓｉ：０．６質量％以下、Ｍｎ：０．０５〜０．３０質量％、Ｐ：０．０３０〜０．１３０質量％、Ｓ：０．０２０〜０．０４０質量％であり、温度が１２３０〜１３５０℃の溶銑に対して脱硫処理を施した。脱硫剤は生石灰単独とし、処理前の溶銑中硫黄濃度に応じて添加量を設定した。また、生石灰の添加前に金属Ａｌを溶銑に添加し、脱硫反応を促進させた。 And a chemical component is C: 3.9-4.9 mass%, Si: 0.6 mass% or less, Mn: 0.05-0.30 mass%, P: 0.030-0.130 mass% , S: 0.020 to 0.040 mass%, and desulfurization treatment was performed on the hot metal having a temperature of 1230 to 1350 ° C. The desulfurizing agent was quick lime alone, and the addition amount was set according to the sulfur concentration in the hot metal before the treatment. In addition, metal Al was added to the hot metal before the addition of quicklime to promote the desulfurization reaction.
実験結果を図９に示す。図９の縦軸の「脱硫石灰効率」とは、溶銑中の硫黄が石灰と反応する化学式を「［Ｓ］＋ＣａＯ＝ＣａＳ＋［Ｏ］」としたときに、下記の（１）式で定義される石灰の利用効率である。
脱硫石灰効率(%)＝{[処理前溶銑中S濃度(質量%)-処理後溶銑中S濃度(質量%)]×10×56/32}/[生石灰添加量(kg/t-溶銑)]…(1)
図９に示すように、邪魔板攪拌では通常攪拌と比較して脱硫石灰効率が約２倍以上に向上しているものの、４チャージ処理した後には、邪魔板が消失してしまった。
The experimental results are shown in FIG. The “desulfurized lime efficiency” on the vertical axis in FIG. 9 is defined by the following formula (1) when the chemical formula in which sulfur in hot metal reacts with lime is “[S] + CaO = CaS + [O]”. The utilization efficiency of lime.
Desulfurized lime efficiency (%) = {[S concentration in hot metal before treatment (mass%)-S concentration in hot metal after treatment (mass%)] x 10 x 56/32} / [Amount of quick lime added (kg / t- hot metal) ] ... (1)
As shown in FIG. 9, the baffle plate agitation improved the desulfurized lime efficiency by about twice or more compared with the normal agitation, but the baffle plate disappeared after the 4-charge treatment.
また、偏心攪拌では、脱硫石灰効率が大きくばらつく結果となり、試験チャンスによっては通常攪拌を下回るものも散見された。これは、インペラーの浸漬位置をＤ／４ずらすことを目標としたが、目視での位置合わせであるので偏心量を一定にはできず、そのために脱硫石灰効率のばらつきが大きくなったと考えている。 In addition, in the case of eccentric stirring, the desulfurized lime efficiency varied greatly, and depending on the test chance, there were some cases where it was below normal stirring. This aimed to shift the immersion position of the impeller by D / 4, but since it was a visual alignment, the amount of eccentricity could not be made constant, and thus the dispersion of desulfurized lime efficiency was considered to have increased. .
一方、底部勾配攪拌では、脱硫石灰効率は、邪魔板攪拌と同様に通常攪拌の約２倍程度に増加し、しかも、ばらつきも小さいことが確認された。また、底部勾配攪拌を同一の溶銑鍋で３００チャージ処理したが、何ら問題は発生せず、通常の溶銑鍋と同等の寿命であり、溶銑受払いなどの脱硫処理以外の操業においても何ら問題は発生しなかった。 On the other hand, in the bottom gradient stirring, it was confirmed that the desulfurized lime efficiency increased to about twice the normal stirring as in the baffle plate stirring, and the variation was small. In addition, although the bottom gradient agitation was 300 charged in the same hot metal ladle, no problem occurred, the life was the same as that of a normal hot metal ladle, and no problems occurred in operations other than desulfurization such as hot metal receiving and discharging. I did not.
図７に示す機械攪拌式脱硫装置において、図８（Ｃ）に示す溶銑鍋を用い、傾斜した平面の傾斜角度θを変化させて溶銑の脱硫処理を実施した。傾斜角度θは、溶銑鍋底部の耐火物の施工量を変えることにより調整した。試験条件をそろえるために、化学成分が、Ｃ：４．４〜４．７質量％、Ｓｉ：０．３〜０．４質量％、Ｍｎ：０．２０〜０．３０質量％、Ｐ：０．１１０〜０．１３０質量％、Ｓ：０．０２８〜０．０３２質量％、温度が１２８０〜１３１０℃の溶銑を用い、この溶銑に脱硫処理を施した。脱硫剤は生石灰単独とし、また、生石灰の添加前に金属Ａｌを溶銑に添加し、脱硫反応を促進させた。図１０に試験結果を示す。尚、図１０には、比較のために、通常の溶銑鍋を使用して脱硫処理した通常攪拌のデータも併せて示している。 In the mechanical stirring type desulfurization apparatus shown in FIG. 7, the hot metal desulfurization treatment was performed by changing the inclination angle θ of the inclined plane using the hot metal ladle shown in FIG. 8C. The inclination angle θ was adjusted by changing the construction amount of the refractory at the bottom of the hot metal pan. In order to align the test conditions, the chemical components were C: 4.4 to 4.7% by mass, Si: 0.3 to 0.4% by mass, Mn: 0.20 to 0.30% by mass, P: 0. .110-0.130 mass%, S: 0.028-0.032 mass%, The hot metal of temperature 1280-1310 degreeC was used, and the desulfurization process was performed to this hot metal. The desulfurization agent was quick lime alone, and metal Al was added to the hot metal before the addition of quick lime to promote the desulfurization reaction. FIG. 10 shows the test results. In addition, in FIG. 10, the data of the normal stirring which carried out the desulfurization process using the normal hot metal ladle are also shown for the comparison.
図１０からも明らかなように、溶銑鍋の底部平面の傾斜角度θが３°よりも小さい、θ＝１°及びθ＝２°の場合には、通常攪拌の場合よりも脱硫石灰効率は高くなったが、その改善効果は少ないことが分かった。一方、θ＝３°からθ＝１０°の範囲では、傾斜角度θを大きくするに伴って、微増ではあるが脱硫石灰効率が高くなることが確認された。しかしながら、傾斜角度θが１０°を超える範囲では、脱硫石灰効率はほぼ一定で、脱硫石灰効率の改善効果は飽和していることが確認できた。 As is clear from FIG. 10, when the inclination angle θ of the bottom plane of the hot metal ladle is smaller than 3 °, θ = 1 ° and θ = 2 °, the desulfurized lime efficiency is higher than in the case of normal stirring. However, it was found that the improvement effect was small. On the other hand, in the range of θ = 3 ° to θ = 10 °, it was confirmed that the desulfurized lime efficiency increased with a slight increase as the inclination angle θ was increased. However, in the range where the inclination angle θ exceeds 10 °, the desulfurized lime efficiency is almost constant, and it has been confirmed that the effect of improving the desulfurized lime efficiency is saturated.
このように、傾斜角度θは３°以上１０°以下の範囲が最適であることが確認できた。 Thus, it was confirmed that the inclination angle θ is optimally in the range of 3 ° to 10 °.
１ 台車
２ 溶銑鍋
３ 溶銑
４ インペラー
５ 上吹きランス
６ 投入シュート
７ 脱硫剤
７Ａ 脱硫剤
８ ホッパー
９ 切出装置
１０ ホッパー
１１ ロータリーフィーダー
１２ 邪魔板
１３ 精錬容器
１４ 鉄皮
１５ 永久煉瓦
１６ ワーク煉瓦
１７ ワーク煉瓦
DESCRIPTION OF SYMBOLS 1 Bogie 2 Hot metal ladle 3 Hot metal 4 Impeller 5 Top blowing lance 6 Input chute 7 Desulfurization agent 7A Desulfurization agent 8 Hopper 9 Cutting device 10 Hopper 11 Rotary feeder 12 Baffle plate 13 Smelting container 14 Iron skin 15 Permanent brick 16 Work brick 17 Work brick brick
Claims (4)
底部の内面形状が該精錬容器の中心軸に対して軸対称とはならないように、前記機械攪拌式脱硫装置のインペラーの下方の底部に施工される耐火物の施工厚みが施工箇所に応じて異なることを特徴とする、溶銑の脱硫処理用精錬容器。 A pan-type refining vessel for desulfurizing the hot metal contained therein with a mechanical stirring desulfurization device,
The construction thickness of the refractory applied to the bottom of the impeller of the mechanical stirring desulfurization device differs depending on the construction location so that the inner shape of the bottom is not axisymmetric with respect to the central axis of the refining vessel A refining vessel for hot metal desulfurization treatment.
底部の外殻が下方に向かって凸状の曲面であり、
前記底部が、前記外殻を形成する鉄皮の内側に施工される耐火物が形成する内面形状の曲率が異なる部分を有し且つ前記底部の内面形状が前記精錬容器の中心軸に対して軸対称とはならないように、底部に施工される耐火物の施工厚みが施工箇所に応じて異なることを特徴とする、溶銑の脱硫処理用精錬容器。 A pan-type refining vessel for desulfurizing the hot metal contained therein with a mechanical stirring desulfurization device,
The outer shell of the bottom is a curved surface that is convex downward.
The bottom portion has a portion with a different curvature of the inner surface shape formed by the refractory applied to the inside of the iron shell forming the outer shell, and the inner surface shape of the bottom portion is an axis with respect to the central axis of the refining vessel A refining vessel for desulfurization treatment of hot metal, characterized in that the construction thickness of the refractory constructed on the bottom differs depending on the construction location so as not to be symmetric.
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| JP6119954B2 (en) * | 2012-08-30 | 2017-04-26 | Ｊｆｅスチール株式会社 | Hot metal desulfurization treatment method |
| JP5999054B2 (en) * | 2013-09-13 | 2016-09-28 | Ｊｆｅスチール株式会社 | Hot metal desulfurization treatment method |
| WO2016142970A1 (en) * | 2015-03-12 | 2016-09-15 | Ｊｆｅスチール株式会社 | Method for desulfurizing molten iron and device for desulfurizing molten iron |
| CN113801976A (en) * | 2020-06-17 | 2021-12-17 | 宝山钢铁股份有限公司 | High-efficiency KR desulfurization hot-metal bottle |
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| CN112024861A (en) * | 2020-08-06 | 2020-12-04 | 首钢京唐钢铁联合有限责任公司 | KR desulfurization ladle inside lining |
| CN112024861B (en) * | 2020-08-06 | 2022-04-26 | 首钢京唐钢铁联合有限责任公司 | KR desulfurization ladle inside lining |
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| JP2011026696A (en) | 2011-02-10 |
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