JP5703616B2 - Method for producing sintered ore - Google Patents
Method for producing sintered ore Download PDFInfo
- Publication number
- JP5703616B2 JP5703616B2 JP2010161945A JP2010161945A JP5703616B2 JP 5703616 B2 JP5703616 B2 JP 5703616B2 JP 2010161945 A JP2010161945 A JP 2010161945A JP 2010161945 A JP2010161945 A JP 2010161945A JP 5703616 B2 JP5703616 B2 JP 5703616B2
- Authority
- JP
- Japan
- Prior art keywords
- ore
- iron ore
- raw material
- sintered
- iron
- 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.)
- Active
Links
Landscapes
- Manufacture And Refinement Of Metals (AREA)
Description
本発明は、製鉄原料として使用される焼結鉱の製造方法に関し、特に、焼結パレット内に形成される原料充填層上部の成品歩留および強度を改善するための焼結鉱の製造方法に関する。 The present invention relates to a method for producing sintered ore used as an ironmaking raw material, and more particularly to a method for producing sintered ore for improving the product yield and strength of the upper part of the raw material packed bed formed in the sintering pallet. .
近年、日本で使用する主要鉄鉱石である豪州産の鉄鉱石においては、良質なヘマタイト鉱石の枯渇化が進み、現状ピソライト鉱床、さらには、マラマンバ鉱床や、高燐ブロックマン鉱床の開発が進んでいる。 In recent years, Australia's iron ore, which is the main iron ore used in Japan, has been depleted of high-quality hematite ore. Yes.
これらの鉱床から産出される鉄鉱石は、良質なヘマタイト鉱石に比べて粒度が小さく、かつ、結晶水の含有量が高いことから、焼結時に、通気性の低下や、焼結反応性の悪化の原因となる。 Iron ore produced from these deposits has a smaller particle size and a higher content of crystal water than high-quality hematite ore, resulting in a decrease in air permeability and deterioration in sintering reactivity during sintering. Cause.
既存の高結晶水鉱石であるピソライト鉱石を加えると、これらの鉱床から産出される鉄鉱石のうちの９割は、結晶水含有量が４質量％以上の鉄鉱石である。 When pisolite ore, which is an existing high crystal water ore, is added, 90% of the iron ore produced from these deposits is iron ore with a crystal water content of 4% by mass or more.
焼結原料として、高結晶水鉱石を多量に配合した場合の焼結操業に及ぼす影響について以下に説明する。 The influence on the sintering operation when a large amount of high crystal water ore is added as a sintering raw material will be described below.
一般に、下方吸引型焼結機を用いた焼結鉱の製造は、次のようにして行われる。 In general, the production of sintered ore using a lower suction type sintering machine is performed as follows.
焼結原料は、主原料である鉄鉱石や製鉄プロセスで発生する製鉄ダストなどの鉄含有原料と、焼結反応に必要となる石灰石および蛇紋岩などの副原料と、熱源としてのコークス粉等の固体燃料とを配合して形成される。 Sintering materials include iron-containing materials such as iron ore as the main material and iron-making dust generated in the iron-making process, auxiliary materials such as limestone and serpentine required for the sintering reaction, coke powder as a heat source, etc. It is formed by blending with solid fuel.
焼結原料は、下方吸引型焼結機に装入する前に、ドラム型ミキサーなどの混合・造粒機を用いて、水添加しながら混合、造粒し、主として、粒径１ｍｍ以上の核粒子と、その周囲に付着した粒径０．５ｍｍ以下の付着粉とからなる擬似粒子とする。 Sintering raw materials are mixed and granulated while adding water using a mixing and granulating machine such as a drum mixer before being charged into the lower suction type sintering machine. A pseudo particle composed of particles and adhering powder having a particle diameter of 0.5 mm or less adhering to the periphery thereof is used.
このことにより、焼結機に装入した後、焼結パレット内に形成された焼結充填層内の通気性を維持し、焼結原料の焼結反応を促進し、高い生産性を確保することができる。 By this, after charging into the sintering machine, the air permeability in the sintered packed bed formed in the sintering pallet is maintained, the sintering reaction of the sintering raw material is promoted, and high productivity is ensured. be able to.
擬似粒子化された焼結原料は、焼結機の給鉱部で、焼結パレット内に装入され、原料充填層を形成した後、点火炉で、その表面のコークス粉に点火されるとともに、焼結機下部に空気吸引することにより、コークス粉の燃焼点を下方に移動させる。 The sintered raw material that has been quasi-particled is charged into the sintering pallet in the feeding section of the sintering machine, and after forming the raw material packed bed, the coke powder on the surface is ignited in the ignition furnace. By sucking air into the lower part of the sintering machine, the combustion point of the coke powder is moved downward.
燃焼熱により原料充填層の上層から下層にかけての焼結反応は順次進行し、焼結パレットが移動し排鉱部に到達するまでに焼結は完了する。焼結パレット内の焼結ケーキ（塊）は、排鉱部から排出された後、破砕され、所定粒度の高炉用の焼結鉱が製造される。 Sintering reaction from the upper layer to the lower layer of the raw material packed layer proceeds sequentially by the heat of combustion, and the sintering is completed by the time the sintering pallet moves and reaches the waste ore section. The sintered cake (lumps) in the sintering pallet is discharged from the waste ore section and then crushed to produce a sintered ore for a blast furnace with a predetermined particle size.
焼結鉱の製造において発生した、高炉用の焼結鉱としての所定粒径より小さい焼結鉱粉は、返鉱として、焼結原料中に配合されて、再度焼結される。 Sintered ore powder having a particle size smaller than a predetermined particle size as a blast furnace sinter produced in the production of the sinter is blended in the sintering raw material as a return ore and sintered again.
焼結原料の焼結反応は、１２００℃付近で、主として、鉄含有原料中のＦｅ2Ｏ3と石灰石中のＣａＯとの反応で、カルシウムフェライト（ＣａＯ−Ｆｅ2Ｏ3）の初期融液を生成し、この融液中に鉄鉱石また副原料中の成分が溶け込む同化反応により進行する。 The sintering reaction of the sintering raw material is a reaction between Fe 2 O 3 in the iron-containing raw material and CaO in the limestone at around 1200 ° C., and an initial melt of calcium ferrite (CaO—Fe 2 O 3 ) is obtained. Produces and proceeds by an assimilation reaction in which the iron ore or the components in the auxiliary raw material are dissolved in the melt.
この焼結反応は、初期融液の生成から数分程度で終了する極めて短い反応であり、この反応により、焼結鉱の成品歩留および生産性、並びに、焼結鉱の強度などの品質が大きく影響される。 This sintering reaction is an extremely short reaction that is completed within a few minutes after the formation of the initial melt. This reaction improves the product yield and productivity of the sintered ore and the quality of the sintered ore. It is greatly affected.
例えば、焼結反応が過剰に進み、生成する融液量が極端に増加すると、焼結操業において、焼結層内の通気が悪化し、これによる焼けムラが発生するため、成品歩留および生産性が低下し、強度などの焼結鉱の品質も悪化することになる。 For example, if the sintering reaction proceeds excessively and the amount of melt produced increases excessively, in the sintering operation, the air flow in the sintered layer deteriorates, resulting in burn unevenness, resulting in product yield and production. As a result, the quality of sintered ore such as strength is deteriorated.
一方、焼結反応が十分に進まない場合は、残留鉄鉱石（残留元鉱）等の未溶融部同士を結合させるための融液が減少するため、成品歩留が低下し、強度や還元粉化（ＲＤＩ）などの焼結鉱の品質の悪化を引き起こすこととなる。 On the other hand, if the sintering reaction does not proceed sufficiently, the melt for bonding unmelted parts such as residual iron ore (residual source ore) decreases, so the product yield decreases, and the strength and reduced powder This will cause deterioration of the quality of sintered ore such as chemical conversion (RDI).
この焼結反応は、配合原料中の主原料であり、全体の６割以上を占める鉄鉱石の鉱物組成や性状などに起因する焼結性（同化性）や、焼結原料充填層の通気性を左右する造粒性に大きく影響される。 This sintering reaction is the main raw material in the blended raw materials, and sinterability (assimilability) due to the mineral composition and properties of iron ore, which accounts for over 60% of the total, and the air permeability of the sintered raw material packed layer It is greatly influenced by the granulation property that affects
鉄鉱石として、ピソライト鉱石などの高結晶水鉄鉱石を配合する場合は、鉄鉱石中のゲーサイト組織に由来する結晶水が、３００℃付近からで熱分解、脱水を開始し、この際、ゲーサイト組織に亀裂が発生する。 When high crystal hydrous ores such as pisolite ore are blended as iron ore, the crystal water derived from the goethite structure in the iron ore starts pyrolysis and dehydration at around 300 ° C. Cracks occur in the site structure.
このため、１２００℃付近から開始する焼結反応時に生成した融液中に気孔が生成したり、残留して凝固、結合相が生成したり、亀裂を含む未溶融元鉱石が残存する結果、焼結鉱は脆弱で多孔質な組織となり、焼結鉱の成品歩留が低下し、強度などの焼結鉱の品質の悪化を引き起こすことになる。 For this reason, pores are generated in the melt generated at the time of the sintering reaction starting from around 1200 ° C., or solidified and bonded phases are formed, and unmelted original ore containing cracks remains. The ore becomes a brittle and porous structure, and the yield of the sintered ore is lowered, and the quality of the sintered ore such as strength is deteriorated.
また、鉄鉱石として、マラマンバ鉱石や高燐鉱石などの結晶水の含有量が高く、粒度が細かい鉄鉱石を配合する場合は、上記の結晶水による問題に加えて、造粒性が悪くなるため、擬似粒子が生成し難く、搬送時や原料装入時に崩壊し易くなる。 In addition, as iron ore, when the content of crystal water such as maramamba ore and high phosphate ore is high and iron ore with a fine particle size is blended, in addition to the above-mentioned problems caused by crystal water, the granulation property becomes worse. , Pseudo particles are not easily generated, and are easily disintegrated at the time of transportation or charging of raw materials.
このため、原料をパレットに装入する際に、造粒されないか、崩壊して生成した鉄鉱石の微粉粒子が原料充填層の上層側に偏析して分布することとなり、上層部の通気性を低下させる原因となる。また、結晶水を含むゲーサイト組織は、脆いため、粒度が細かい鉄鉱石粒子に多く存在する。 For this reason, when the raw material is charged into the pallet, the fine particles of iron ore that are not granulated or disintegrated are segregated and distributed on the upper layer side of the raw material packed layer, thereby improving the air permeability of the upper layer part. It causes a decrease. Further, since the goethite structure containing crystal water is brittle, there are many iron ore particles having a small particle size.
このため、原料充填層の上層側に偏析して分布する鉄鉱石の微粉粒子は、上記の結晶水に起因する問題を引き起こす原因にもなる。 For this reason, the fine powder particles of iron ore that are segregated and distributed on the upper layer side of the raw material packed bed also cause a problem caused by the crystal water.
一般に、下方吸引型焼結機を用いた焼結鉱の製造においては、室温に近い空気の吸引により、着火後の原料充填層の表層部の温度が低下することに起因し、上層部における焼結鉱の成品歩留の低下および強度等の品質悪化が、従来から問題となっていた。 Generally, in the production of sintered ore using a lower suction type sintering machine, the temperature of the surface layer portion of the raw material packed layer after ignition is lowered due to the suction of air close to room temperature, and the sintering in the upper layer portion is performed. Conventionally, a decrease in product yield of the ore and deterioration of quality such as strength have been problems.
この上層部における焼結鉱の成品歩留および強度等の品質の問題は、近年の鉄鉱石として焼結原料高結晶水鉄鉱石および細粒鉄鉱石を配合する焼結操業において顕著である。 The problem of quality such as product yield and strength of the sintered ore in the upper layer is remarkable in a sintering operation in which a sintering raw material high-crystal water ore and fine-grained iron ore are blended as a recent iron ore.
上記下方吸引型焼結機を用いた焼結鉱の製造における、焼結原料充填層の上層部における成品歩留および強度などの品質を向上するための方法は、今までに、数多く提案されている。 In the production of sintered ore using the lower suction type sintering machine, many methods have been proposed so far to improve the quality of product yield and strength in the upper layer of the sintered raw material packed layer. Yes.
例えば、原料充填層上層部へ固体燃料を増加させる方法（例えば、特許文献１、参照）が提案されている。 For example, a method of increasing the amount of solid fuel to the upper part of the raw material packed bed (for example, see Patent Document 1) has been proposed.
また、磁気を利用した装入装置により、返鉱、ミルスケール、マグネタイトなどの高ＦｅＯ強磁性原料および強磁性原料と炭材の造粒物を、原料充填層の表層部に装入する方法（例えば、特許文献２〜６、参照）も提案されている。 In addition, a high FeO ferromagnetic raw material such as return mineral, mill scale, and magnetite, and a granulated product of a ferromagnetic raw material and a carbonaceous material are charged into the surface layer portion of the raw material packed bed by using a magnetic charging device ( For example, Patent Documents 2 to 6 are also proposed.
また、焼結原料に配合する鉄鉱石の同化溶融性を考慮し、原料充填層の上層に易溶融性鉄鉱石を装入し、その下層部に、難溶融性鉄鉱石を装入する方法（例えば、特許文献７参照）も提案されている。 In addition, in consideration of the assimilation and melting properties of iron ore to be blended with the sintering raw material, a method of charging easily fusible iron ore into the upper layer of the raw material packed layer and charging poorly fusible iron ore into the lower layer ( For example, see Patent Document 7).
これらの方法は、着火後の原料充填層の表層部の温度を上昇させるために、原料充填層の表層部の固体燃料を増加したり、原料充填層の表層部中に副原料中のＣａＯやＳｉＯ2と融液（ＣａＯ−ＳｉＯ2−ＦｅＯ）を生成し易いＦｅＯを多く含有する強磁性原料や、易溶融性鉄鉱石などを装入することにより、原料充填層上層部の焼結鉱の成品歩留および強度等の品質を向上させる方法である。 In these methods, in order to increase the temperature of the surface layer portion of the raw material packed layer after ignition, the solid fuel in the surface layer portion of the raw material packed layer is increased, or CaO in the auxiliary raw material is included in the surface layer portion of the raw material packed layer. By inserting a ferromagnetic raw material containing a large amount of FeO that easily generates SiO 2 and a melt (CaO—SiO 2 —FeO), or an easily fusible iron ore, This is a method of improving quality such as product yield and strength.
また、本願発明の発明者等は、先願において複数銘柄の鉄鉱石を含む鉄含有原料、副原料、固体燃料、および、返鉱を配合して焼結原料とし、該焼結原料を混合、造粒した後、焼結パレット内に装入し、焼成する焼結鉱の製造方法において、前記鉄鉱石の銘柄毎に融液浸透性の評価試験を行い、鉄鉱石粉中への融液浸透距離の測定値に基づいて、前記複数銘柄の鉄鉱石のうちで、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である１種または２種以上からなる鉄鉱石を、前記焼結パレット内に形成する原料充填層上部の全層厚に対する層厚比率で５〜１２％の範囲に装入し、その他の鉄鉱石を原料充填層下部に装入し、かつ、前記副原料、固体燃料、および、返鉱は、原料充填層の上部および下部で、同じ配合割合で装入することを特徴とする焼結鉱の製造方法と提案している（特許文献８）。 In addition, the inventors of the present invention, in the prior application, iron-containing raw materials containing multiple brands of iron ore, auxiliary raw materials, solid fuel, and return ore are mixed into a sintered raw material, and the sintered raw material is mixed, In the method for producing sintered ore, which is granulated, then charged into a sintering pallet and fired, an evaluation test of melt permeability is performed for each brand of iron ore, and the melt penetration distance into iron ore powder In the sintered pallet, one or two or more kinds of iron ores having a melt penetration distance into the iron ore powder of 4.0 mm or more among the iron ores of the plurality of brands based on the measured values of In the range of 5 to 12% in the layer thickness ratio with respect to the total layer thickness of the upper part of the raw material packed bed to be formed, other iron ore is charged in the lower part of the raw material packed bed, and the auxiliary raw material, solid fuel, The return ore is charged at the same mixing ratio in the upper and lower parts of the raw material packed bed. That proposes a method for producing a sintered ore (Patent Document 8).
しかし、特許文献１乃至７に記載の発明は、原料充填層の上層の熱量や融液生成量を適度に制御することは難しく、熱量が高過ぎたり、融液が過度に増加すると、原料充填層全体の通気性が悪化して、生産性を低下させ、被還元性などの焼結鉱の品質を低下させるという問題があった。 However, in the inventions described in Patent Documents 1 to 7, it is difficult to appropriately control the amount of heat and the amount of melt generated in the upper layer of the raw material filling layer, and if the amount of heat is too high or the melt increases excessively, the raw material filling There was a problem that the air permeability of the entire layer deteriorated, the productivity was lowered, and the quality of sintered ore such as reducibility was lowered.
また、本願発明の発明者等による先願に係る発明（特許文献８）においては、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である鉄鉱石を、焼結パレット内の原料充填層上部に装入する場合に、前記鉄鉱石の装入は、全層厚に対する層厚比率で５〜１２％の範囲に制限されるという問題があった。 In the invention according to the prior application by the inventors of the present invention (Patent Document 8), an iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more is used as a raw material packed layer in a sintering pallet. When charging in the upper part, there was a problem that the charging of the iron ore was limited to a range of 5 to 12% in the layer thickness ratio with respect to the total layer thickness.
上記従来技術の問題点に鑑みて、本発明は、下方吸引型焼結機を用いた焼結鉱の製造方法において、原料充填層の上層の融液が過度に増加することにより、原料充填層全体の通
気性を悪化させ、生産性を低下させ、被還元性などの焼結鉱の品質を低下させることなく
、原料充填層上部に微粉部への融液浸透性に優れ、原料充填層上部の成品歩留および強度を改善し、焼結鉱の生産性を向上することができる焼結鉱の製造方法を提供することを目的とする。
更に、本願発明の発明者等による先願に係る発明（特許文献８）を一歩進め、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である鉄鉱石を、焼結パレット内の原料充填層上部に装入する場合に、前記鉄鉱石の装入を、全層厚に対する層厚比率で５〜５０％の範囲に広げることができる焼結鉱の製造方法を提供することを目的とする。
In view of the above-mentioned problems of the prior art, the present invention provides a raw material packed bed by increasing the melt of the upper layer of the raw material packed layer in the sintered ore manufacturing method using the lower suction type sintering machine. It has excellent melt permeability to the fine powder part on the upper part of the raw material packed layer without lowering the overall air permeability, lowering the productivity, and reducing the quality of sintered ore such as reducibility, and the upper part of the raw material packed layer An object of the present invention is to provide a method for producing a sintered ore that can improve the yield and strength of the product and improve the productivity of the sintered ore.
Furthermore, the invention according to the prior application by the inventors of the present invention (Patent Document 8) is advanced one step, and the iron ore whose melt penetration distance into the iron ore powder is 4.0 mm or more is filled with the raw material in the sintered pallet. An object of the present invention is to provide a method for producing a sintered ore that can expand the charging of the iron ore to a range of 5 to 50% in a layer thickness ratio with respect to the total layer thickness when charging to the upper part of the layer. .
本発明者らは、焼結鉱の製造において焼結パレットに形成される原料充填層上部の成品
歩留および強度を改善するための方法を鋭意検討した。
The present inventors diligently studied a method for improving the product yield and strength of the upper part of the raw material packed bed formed on the sintered pallet in the production of sintered ore.
その結果、焼結原料を構成する複数銘柄の鉄鉱石のうちで、鉄鉱石粉中への融液浸透性
の評価試験により測定した鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石を、焼結パレットを形成する原料充填層上部の所定範囲に装入することにより、原料充填層上部の成品歩留および強度を改善できることを確認した。
As a result, among the multiple brands of iron ore constituting the sintered raw material, the melt penetration distance into the iron ore powder measured by the evaluation test of the melt penetration into the iron ore powder is 4.0 mm or more, Moreover, the product yield and strength of the upper part of the raw material packed bed are charged by charging iron ore obtained by crushing particles having a particle size of 1 mm or more to 10% by mass or less into a predetermined range of the upper part of the raw material packed bed forming the sintered pallet. It was confirmed that can be improved.
この方法によれば、従来提案されている原料充填層上部の固体燃料やＦｅＯ源を増加する方法や、原料充填層の上層に易溶融性鉄鉱石を装入する方法に比べて、原料充填層上部に過度の融液を生成し、原料充填層全体の通気性を低下させることなく、上層部の焼結鉱の成品歩留および強度を改善できる。 According to this method, compared to the conventionally proposed method of increasing the solid fuel and FeO source at the upper part of the raw material packed bed and the method of charging the easily meltable iron ore into the upper layer of the raw material packed bed, the raw material packed bed It is possible to improve the product yield and strength of the sintered ore in the upper layer portion without generating an excessive melt at the upper portion and reducing the air permeability of the entire raw material packed layer.
また、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の鉄鉱石を粒径１ｍｍ以上の粒子を１０質量％以下に破砕して、焼結パレット内の原料充填層上部に装入する場合は、全層厚に対する上層厚比率で５〜５０％の範囲に広げることができる。 Also, when iron ore with a melt penetration distance of 4.0 mm or more into iron ore powder is crushed into particles with a particle size of 1 mm or more to 10% by mass or less and charged into the upper part of the raw material packed bed in the sintering pallet Can be expanded in the range of 5 to 50% in the ratio of the upper layer thickness to the total layer thickness.
本発明は、上記知見に基づいてなされたもので、その発明の要旨は、以下のとおりである。 The present invention has been made based on the above findings, and the gist of the invention is as follows.
（１）複数銘柄の鉄鉱石を含む鉄含有原料、副原料、固体燃料、および、返鉱を配合して焼結原料とし、該焼結原料を混合、造粒した後、焼結パレット内に装入し、焼成する焼結鉱の製造方法において、
前記複数銘柄の鉄鉱石を銘柄毎に融液浸透性の評価試験を行い、鉄鉱石粉中への融液浸透距離の測定値に基づいて鉄鉱石粉中への融液浸透距離を測定する融液浸透距離測定工程と、
前記複数銘柄の鉄鉱石のうち、融液浸透距離が４．０mm以上で、かつ、結晶水が１．２６質量％以下の鉄鉱石の一部又は全部を、粒径１mm以上の粒子が１０質量％以下となるように破砕する鉱石破砕工程と、
前記破砕した鉄鉱石と、破砕していないその他の鉄鉱石、副原料、固体燃料、および返鉱とを混合、造粒して原料を製造する混合、造粒工程と、
前記混合、造粒した原料を、焼結パレット内に形成する原料充填層の上部に全層厚に対する層厚比率で上表面から５％〜上表面から５０％の範囲に装入する装入工程とを実施することを特徴とする焼結鉱の製造方法。
(1) Iron-containing raw materials containing multiple brands of iron ore, secondary raw materials, solid fuel, and return ore are mixed to form a sintered raw material. After mixing and granulating the sintered raw material, In the method for producing sintered ore that is charged and fired,
Perform the melt penetration evaluation test for each brand of iron ore for each brand and measure the melt penetration distance into the iron ore powder based on the measured value of the melt penetration distance into the iron ore powder. A distance measurement process;
Among the iron ores of multiple brands, a part or all of the iron ore having a melt penetration distance of 4.0 mm or more and a crystal water of 1.26% by mass or less , and particles having a particle diameter of 1 mm or more are 10 masses. Ore crushing step of crushing to less than
Mixing and granulating the crushed iron ore with other crushed iron ore, secondary raw materials, solid fuel, and returning ore to produce raw materials,
A charging step of charging the mixed and granulated raw material in a range of 5% from the upper surface to 50% from the upper surface at a layer thickness ratio with respect to the total layer thickness on the raw material packed layer formed in the sintering pallet. And a method for producing a sintered ore.
（２）前記（１）に記載の焼結鉱の製造方法において、
前記装入工程は、二段装入法により行われることを特徴とする焼結鉱の製造方法。
（３）前記（１）に記載の焼結鉱の製造方法において、
前記装入工程は、原料粒度偏析装入法により行われることを特徴とする焼結鉱の製造方法。
(2) In the method for producing a sintered ore according to (1),
The method for producing sintered ore, wherein the charging step is performed by a two-stage charging method.
(3) In the method for producing a sintered ore according to (1),
The said charging process is performed by the raw material particle size segregation charging method, The manufacturing method of the sintered ore characterized by the above-mentioned.
（４）前記（１）乃至（３）のいずれかに記載の焼結鉱の製造方法において、
前記融液浸透距離が４．０ｍｍ以上の鉄鉱石が、更に、気孔率が０．０５ｃｃ/ｇ以上であることを特徴とする焼結鉱の製造方法。
(4) In the method for producing a sintered ore according to any one of (1) to (3),
The method for producing a sintered ore, wherein the iron ore having a melt penetration distance of 4.0 mm or more further has a porosity of 0.05 cc / g or more.
本発明によれば、下方吸引型焼結機を用いた焼結鉱の製造方法において、焼結原料に配合する各銘柄鉄鉱石の微粉部への融液浸透性を評価し、この評価結果に基づき、各銘柄鉄鉱石のうち、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石を原料充填層上部に装入することにより、原料充填層上部の成品歩留および強度を改善し、焼結鉱の生産性を向上することができる。 According to the present invention, in the method for producing sintered ore using the lower suction type sintering machine, the melt permeability to the fine powder portion of each brand iron ore to be blended with the sintering raw material is evaluated, and this evaluation result Based on the iron ore of each brand, the iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more and crushed particles having a particle diameter of 1 mm or more to 10% by mass or less is formed on the upper part of the raw material packed bed. By charging, the product yield and strength of the upper part of the raw material packed bed can be improved, and the productivity of the sintered ore can be improved.
まず、本発明の技術思想について説明する。 First, the technical idea of the present invention will be described.
図１は、焼結機の原料充填層から採取した焼結原料の擬似粒子断面の顕微鏡組織を示す図である。 FIG. 1 is a view showing a microstructure of a pseudo-particle cross section of a sintered raw material collected from a raw material packed layer of a sintering machine.
焼結過程で初期融液は、鉄鉱石（Ｆｅ2Ｏ3）と石灰石（ＣａＯ）が接触した部位で生成すると考えられるが、図１に示すとおり、焼結原料の擬似粒子（粒径１ｍｍ以上の核粒子と、その周囲の粒径０．５ｍｍ以下の付着粉部で構成される）の付着粉部のミクロ観察によれば、鉄鉱石（Ｆｅ2Ｏ3）と石灰石（ＣａＯ）の接触部位は少なく、これらは、不規則に分布している。 In the sintering process, the initial melt is considered to be generated at a site where iron ore (Fe 2 O 3 ) and limestone (CaO) are in contact with each other. As shown in FIG. According to the micro observation of the adhering powder part of the core particle and the surrounding adhering powder part having a particle size of 0.5 mm or less, the contact site of iron ore (Fe 2 O 3 ) and limestone (CaO) There are few, and these are irregularly distributed.
このことから、実際の焼結過程では、焼結原料の擬似粒子の付着粉部中の鉄鉱石（Ｆｅ2Ｏ3）と石灰石（ＣａＯ）の接触部位で、カルシウムフェライト（ＣａＯ−Ｆｅ2Ｏ3）の初期融液が生成した後、初期融液が原料微粉内に浸透し、その他の鉄鉱石や副原料と接触し、同化、合体を繰り返しながら融液量を増加させることで焼結反応が進行し、その結果、焼結鉱の結合相が形成されると考えられる。 From this, in the actual sintering process, calcium ferrite (CaO—Fe 2 O 3 ) at the contact site between iron ore (Fe 2 O 3 ) and limestone (CaO) in the adhering powder part of the pseudo particles of the sintering raw material. After the initial melt is formed, the initial melt penetrates into the raw material fine powder, comes into contact with other iron ores and auxiliary raw materials, and increases the amount of the melt while repeating assimilation and coalescence. As a result, it is considered that a binder phase of sinter is formed.
なお、本発明者らは、焼結過程で生成した初期融液が鉄鉱石充填層内に浸透する挙動、即ち、融液浸透性は鉄鉱石の鉱物特性に依存し、この融液の拡がりが焼結鉱の結合相形成に大きく影響することを明らかにしている（ＩＳＩＪ−Ｉｎｔ.４３（２００３）,ｐ.１３８４、参照）。 The inventors of the present invention have found that the behavior of the initial melt generated in the sintering process penetrates into the iron ore packed bed, that is, the melt permeability depends on the mineral characteristics of the iron ore, and the spread of the melt It has been clarified that this greatly affects the formation of the binder phase of the sinter (see ISIJ-Int. 43 (2003), p. 1384).
本発明者らは、焼結操業中で焼結原料充填層の上層部の温度は低くなり易く、かつ、鉄鉱石（Ｆｅ2Ｏ３）と石灰石（ＣａＯ）との初期融液の生成から焼結反応（同化反応）が完了する時間は短いことに鑑みて、原料充填層の上層部における焼結鉱の成品歩留を向上するためには、原料充填層の上層部に、融液浸透性の高く、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石を選択的に装入し、生成した初期融液を、速やかに原料微粉部中に浸透させ、同化反応を促進することが有効であると考えた。 In the sintering operation, the present inventors tend to lower the temperature of the upper layer of the sintering raw material packed layer, and from the formation of the initial melt of iron ore (Fe 2 O 3 ) and limestone (CaO). In view of the short time required for completion of the calcination reaction (anabolic reaction), in order to improve the yield of sintered ore in the upper layer of the raw material packed layer, the upper part of the raw material packed layer has a melt permeability. The iron ore that is crushed into particles with a particle size of 1 mm or more and having a particle size of 1 mm or more is selectively charged, and the generated initial melt is rapidly infiltrated into the raw fine powder part to promote the assimilation reaction. I thought it was effective.
本発明は、この技術思想に基づいてなされたものであり、複数銘柄の鉄鉱石を含む鉄含有原料、副原料、および、固体燃料を配合して焼結原料とし、該焼結原料を混合、造粒した後、焼結パレット内に装入し、焼成する焼結鉱の製造方法において、前記鉄鉱石の銘柄毎に融液浸透性の評価試験を行い、鉄鉱石粉中への融液浸透距離の測定値に基づいて、前記複数銘柄の鉄鉱石のうちで、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である鉄鉱石を、粒径１ｍｍ以上の粒子が１０質量％以下となるように破砕し、前記焼結パレット内に形成する原料充填層上部の層厚５〜５０％の範囲に装入することを特徴とする。 The present invention was made based on this technical idea, iron-containing raw materials containing a plurality of brands of iron ore, auxiliary raw materials, and a solid fuel is mixed into a sintered raw material, and the sintered raw material is mixed. In the method for producing sintered ore, which is granulated, then charged into a sintering pallet and fired, an evaluation test of melt permeability is performed for each brand of iron ore, and the melt penetration distance into iron ore powder Based on the measured value of the above, among the iron ores of a plurality of brands, the iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more is 10% by mass or less of particles having a particle size of 1 mm or more. Thus, the material is crushed and charged in a range of 5 to 50% of the thickness of the upper part of the raw material packed layer formed in the sintered pallet.
本発明において、鉄鉱石の融液浸透性（初期融液が粒径０．５ｍｍ以下の鉄鉱石粉中へ浸透する際の拡がり易さ）、および、鉄鉱石粉中の融液浸透距離は、本発明者らが、特開２００２−６２２９０号公報などで提案した評価試験（以下、「鉄鉱石の融液浸透性評価試験」という）によって評価、測定することができる。 In the present invention, the melt permeability of the iron ore (ease of spreading when the initial melt penetrates into the iron ore powder having a particle size of 0.5 mm or less) and the melt penetration distance in the iron ore powder are determined according to the present invention. They can be evaluated and measured by an evaluation test proposed by JP-A-2002-62290 or the like (hereinafter, referred to as “iron ore melt permeability evaluation test”).
つまり、本発明における鉄鉱石の融液浸透性評価試験、および、鉄鉱石粉中への融液浸透距離の測定は、以下の要領で行うことができる。 That is, the melt permeability evaluation test of iron ore and the measurement of the melt penetration distance into the iron ore powder in the present invention can be performed as follows.
鉄鉱石試料は、粒径：０．２５〜０．５ｍｍの割合が５０質量％で、かつ、粒径：０．２５ｍｍ以下の割合が５０質量％となるように粒度調整し、十分に混合した後、金型成形ダイスを用いて、成形圧力：４Ｍｐａで成形し、直径：１５ｍｍ、高さ：５ｍｍの鉄鉱石タブレット(水銀圧入法による空隙率（開気孔率）：約３０％)とする。 The iron ore sample was adjusted in particle size so that the ratio of particle size: 0.25 to 0.5 mm was 50% by mass, and the ratio of particle size: 0.25 mm or less was 50% by mass, and mixed well. Thereafter, using a mold forming die, molding is performed at a molding pressure of 4 Mpa to obtain an iron ore tablet having a diameter of 15 mm and a height of 5 mm (porosity (open porosity) by mercury intrusion method: about 30%).
一方、初期融液材は、ＣａＯ−Ｆｅ2Ｏ3の２元系状態図の共晶組成に近いＣａＯ：２６質量％、Ｆｅ2Ｏ３：７４質量％の組成になるように、Ｆｅ2Ｏ３試薬とＣａＯ試薬を配合し、自動乳鉢で２０分間混合した後、鉄鉱石タブレットと同様に、金型成形ダイスを用いて成形圧力：４ＭＰａで成形し、直径：５ｍｍ、高さ：５ｍｍの初期融液材タブレットとする。 On the other hand, the initial melt material is close to the eutectic composition of the binary system phase diagram of CaO-Fe 2 O 3 CaO: 26 wt%, Fe 2 O 3: As will become 74% by weight of the composition, Fe 2 O 3 reagents and CaO reagent were mixed and mixed for 20 minutes in an automatic mortar, then, like an iron ore tablet, molded with a molding die at a molding pressure of 4 MPa, diameter: 5 mm, height: 5 mm A melt material tablet is used.
鉄鉱石粉中への融液浸透距離は、前記鉄鉱石タブレット上面の中心部に、前記初期融液材タブレットを載せて、Ｎｉ製円筒型坩堝（内径２０ｍｍ、高さ１５ｍｍ）に装入し、電気炉内において空気気流中で加熱し、焼成した後、焼成後のタブレットの断面観察により融液浸透距離を測定する。 The melt penetration distance into the iron ore powder was measured by placing the initial melt material tablet in the center of the upper surface of the iron ore tablet and charging it into a Ni cylindrical crucible (inner diameter 20 mm, height 15 mm). After heating and baking in an air stream in the furnace, the melt penetration distance is measured by observing the cross section of the tablet after baking.
なお、焼成後のタブレットにおける融液浸透距離の測定は、タブレット径方向中央部で垂直に切断し、切断面を研磨し、図２に示すように、切断面の鉱物組織を顕微鏡により観察し、撮影した断面組織において、融液が浸透した部分の幅方向（タブレット径方向）中心部(図２中(3)と、この中心部(3)と先端(1)と(5)の中間点である(2)および(4)の３箇所で浸透距離を実測し、それらの平均値から融液浸透距離を求めることが好ましい。 In addition, the measurement of the melt penetration distance in the tablet after baking, cut perpendicularly in the tablet radial direction central portion, polished the cut surface, as shown in FIG. 2, observe the mineral structure of the cut surface with a microscope, In the photographed cross-sectional tissue, the width direction (tablet radial direction) center part of the portion where the melt penetrated ((3) in FIG. 2 and at the midpoint between this center part (3) and the tip (1) and (5)) It is preferable to actually measure the permeation distance at three locations (2) and (4) and obtain the melt permeation distance from the average value thereof.
上記評価試験において、タブレットの焼成条件は、実機の焼結ヒートパターンに近似させ、１１００℃から１２９０℃（最高温度）までを１分で加熱した後、１２９０℃から１１００℃までを３分で冷却し、直ちに、タブレットを炉外へ取り出し空冷する。 In the above evaluation test, the tablet baking conditions are approximated to the sintering heat pattern of the actual machine, heated from 1100 ° C to 1290 ° C (maximum temperature) in 1 minute, and then cooled from 1290 ° C to 1100 ° C in 3 minutes. Immediately take the tablet out of the furnace and allow it to cool.
表１に、焼結原料に配合する主要銘柄の鉄鉱石の化学成分組成と、融液浸透性評価試験で測定された鉄鉱石粉中への融液浸透距離を示す。 Table 1 shows the chemical composition of the main brand iron ore blended in the sintered raw material and the melt penetration distance into the iron ore powder measured in the melt penetration evaluation test.
表１において、Ｂ（ａ）およびＢ（ｂ）は、２種類のブラジル産鉱石、Ｈ（ａ）およびＨ（ｂ）は、２種類の豪州産ヘマタイト鉱石、Ｍ（ａ）およびＭ（ｂ）は、２種類の豪州産マラマンバ鉱石、ＨＰ（ａ）およびＨＰ（ｂ）は、２種類の豪州産高りん鉱石、Ｐ（ａ）およびＰ（ｂ）は、２種類の豪州産ピソライト鉱石、ＨＰＭは、豪州産新規ブレンド鉱石、Ｉ（ａ）およびＩ（ｂ）は、２種類のインド産鉱石を示す。また、Ｓは、製鉄プロセスで発生するスケールを示す。 In Table 1, B (a) and B (b) are two Brazilian ores, H (a) and H (b) are two Australian hematite ores, M (a) and M (b) Are two Australian maramamba ores, HP (a) and HP (b) are two Australian high phosphate ores, P (a) and P (b) are two Australian pisolite ores, HPM Are new blended ores from Australia, I (a) and I (b) represent two types of Indian ores. S indicates a scale generated in the iron making process.
図３は、表１に示す主要銘柄の鉄鉱石の鉄鉱石粉中への融液浸透距離の比較を示す図である。表１および図３によれば、主要銘柄の鉄鉱石の中で、２種類のブラジル産鉱石Ｂ（ａ）およびＢ（ｂ）は、いずれも、鉄鉱石粉中の融液浸透距離が４．０ｍｍ以上と高いことが解る。 FIG. 3 is a diagram showing a comparison of melt penetration distances of iron ores of main brands shown in Table 1 into iron ore powder. According to Table 1 and FIG. 3, among the major brands of iron ore, the two Brazilian ores B (a) and B (b) both have a melt penetration distance of 4.0 mm in the iron ore powder. It can be seen that this is high.
一方、２種類の豪州産ヘマタイト鉱石Ｈ（ａ）およびＨ（ｂ）、２種類の豪州産高りん鉱石ＨＰ（ａ）およびＨＰ（ｂ）、および、２種類の豪州産ピソライト鉱石Ｐ（ａ）およびＰ（ｂ）は、何れも鉄鉱石粉中の融液浸透距離は２．０ｍｍ以下と低いことが解る。 On the other hand, two Australian hematite ores H (a) and H (b), two Australian high-phosphorus ores HP (a) and HP (b), and two Australian pisolite ores P (a) As for P and (b), it is understood that the melt penetration distance in the iron ore powder is as low as 2.0 mm or less.
また、豪州産新規ブレンド鉱石ＨＰＭ、２種類の豪州産マラマンバ鉱石Ｍ（ａ）、Ｍ（ｂ）、および、２種類のインド産鉱石Ｉ（ａ）およびＩ（ｂ）は、融液浸透距離が２．０ｍｍ超〜４．０ｍｍ未満の範囲にあることが解る。 In addition, Australian new blended ore HPM, two Australian maramamba ores M (a) and M (b), and two Indian ores I (a) and I (b) have a melt penetration distance. It turns out that it exists in the range of more than 2.0 mm-less than 4.0 mm.
なお、豪州産ピソライト鉱石Ｐ（ａ）およびＰ（ｂ）は、結晶水含有量が高く、焼結反応において同化溶融し易い、易溶融性鉄鉱石として知られるが、鉄鉱石粉中の融液浸透距離は２．０ｍｍ以下と低く、融液浸透性は良くない鉄鉱石であることが解る。また、製鉄プロセスで発生するスケールＳも、粉中の融液浸透性距離が４．０ｍｍ以上と高いことが解る。 Australian pisolite ores P (a) and P (b) are known as easily meltable iron ores that have a high crystallization water content and are easily assimilated and melted in the sintering reaction. It can be seen that the distance is as low as 2.0 mm or less, and the iron ore has poor melt permeability. It can also be seen that the scale S generated in the iron making process has a high melt permeability distance of 4.0 mm or more in the powder.
ここで、本願発明者等は、先願（特許文献８）において焼結鉱の製造方法を提案しているので、先願発明との対比において、本願発明を説明する。
先願（特許文献８）に係る発明は、「複数銘柄の鉄鉱石を含む鉄含有原料、副原料、固体燃料、および、返鉱を配合して焼結原料とし、該焼結原料を混合、造粒した後、焼結パレット内に装入し、焼成する焼結鉱の製造方法において、前記鉄鉱石の銘柄毎に融液浸透性の評価試験を行い、鉄鉱石粉中への融液浸透距離の測定値に基づいて、前記複数銘柄の鉄鉱石のうちで、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である１種または２種以上からなる鉄鉱石を、前記焼結パレット内に形成する原料充填層上部の全層厚に対する層厚比率で５〜１２％の範囲に装入し、その他の鉄鉱石を原料充填層下部に装入し、かつ、前記副原料、固体燃料、および、返鉱は、原料充填層の上部および下部で、同じ配合割合で装入することを特徴とする焼結鉱の製造方法」である。
Here, since the inventors of this application have proposed the manufacturing method of a sintered ore in a prior application (patent document 8), this invention is demonstrated in contrast with the prior application invention.
The invention according to the prior application (Patent Document 8) is described as follows: “Iron-containing raw material containing multiple brands of iron ore, auxiliary raw material, solid fuel, and return ore are mixed into a sintered raw material, and the sintered raw material is mixed, In the method for producing sintered ore, which is granulated, then charged into a sintering pallet and fired, an evaluation test of melt permeability is performed for each brand of iron ore, and the melt penetration distance into iron ore powder In the sintered pallet, one or two or more kinds of iron ores having a melt penetration distance into the iron ore powder of 4.0 mm or more among the iron ores of the plurality of brands based on the measured values of In the range of 5 to 12% in the layer thickness ratio with respect to the total layer thickness of the upper part of the raw material packed bed to be formed, other iron ore is charged in the lower part of the raw material packed bed, and the auxiliary raw material, solid fuel, And return ore is charged at the same mixing ratio in the upper and lower parts of the raw material packed bed. It is a manufacturing method of a mineral. "
これに対し、本願発明は、「複数銘柄の鉄鉱石を含む鉄含有原料、副原料、固体燃料、および、返鉱を配合して焼結原料とし、該焼結原料を混合、造粒した後、焼結パレット内に装入し、焼成する焼結鉱の製造方法において、前記複数銘柄の鉄鉱石を銘柄毎に融液浸透性の評価試験を行い、鉄鉱石粉中への融液浸透距離の測定値に基づいて鉄鉱石粉中への融液浸透距離を測定し、前記融液浸透距離が４．０ｍｍ以上の鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕した鉄鉱石を製造し、前記鉄鉱石と、その他の鉄鉱石、副原料、固体燃料、および、返鉱と混合、造粒した原料を製造し、前記混合、造粒した原料を、焼結パレット内に形成する原料充填層の上部に全層厚に対する層厚比率で５〜５０％の範囲に装入することを特徴とする焼結鉱の製造方法」である。 On the other hand, the invention of the present application is “after mixing iron-containing raw materials containing multiple brands of iron ore, auxiliary raw materials, solid fuel, and return ore into sintered raw materials, and mixing and granulating the sintered raw materials. In the method for producing sintered ore that is charged into a sintering pallet and fired, the iron ore of the plurality of brands is subjected to a melt permeability evaluation test for each brand, and the melt penetration distance into the iron ore powder is measured. Based on the measured values, the melt penetration distance into the iron ore powder is measured, and iron ore in which the iron ore with the melt penetration distance of 4.0 mm or more is crushed to 10 mass% or less of particles with a particle diameter of 1 mm or more is manufactured. The iron ore and other iron ore, secondary raw material, solid fuel, and raw material mixed and granulated with the return ore are manufactured, and the mixed and granulated raw material is formed in a sintered pallet. It is characterized in that it is charged in the range of 5 to 50% in the layer thickness ratio with respect to the total layer thickness above the packed layer. It is a manufacturing method "of sintered ore.
先願発明が、「鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である１種または２種以上からなる鉄鉱石を、前記焼結パレット内に形成する原料充填層上部の全層厚に対する層厚比率で５〜１２％の範囲に装入する」のに対し、本願発明は、「鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上である鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕し、原料充填層上部の全層厚に対する層厚比率で５〜５０％の範囲に装入する」点で相違する。 The invention of the prior application states that “the total thickness of the upper part of the raw material packed bed in which one or two or more types of iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more is formed in the sintered pallet” In contrast, the invention of the present application states that "the iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more is a particle having a particle diameter of 1 mm or more" Is crushed to 10% by mass or less and charged in a range of 5 to 50% in a layer thickness ratio with respect to the total thickness of the upper part of the raw material packed layer.
本願発明は、融液浸透性が優れた鉄鉱石を、粒径１ｍｍ以上の粒子を１０質量％以下に破砕することに技術的特徴を有しているので、その意義を説明する。 The present invention has a technical feature in crushing iron ore excellent in melt permeability to particles having a particle diameter of 1 mm or more to 10% by mass or less, and the significance thereof will be described.
鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の融液浸透性を有する鉄鉱石は、前記表１に示すＢ（ａ）又はＢ（ｂ）であり、ブラジル産鉱石である。近年、日本で使用する主要鉄鉱石である豪州産鉱石は、微粉が多く、かつ、結晶水含有率が高い劣質鉱石であるのに対し、前記ブラジル産鉱石は、鉄分は高く、結晶水や微粉の少ない高品位鉱石である。当該高品位鉱石は、破砕することなく擬似粒子の核粒子として使用されているのが、当業者の周知な技術である。 The iron ore having a melt permeability having a melt penetration distance of 4.0 mm or more into the iron ore powder is B (a) or B (b) shown in Table 1 and is a Brazilian ore. In recent years, Australian ores, which are the main iron ores used in Japan, are inferior ores with a lot of fine powder and a high content of crystal water, whereas the Brazilian ore has a high iron content, and crystal water and fine powder. It is a high-grade ore with a low content. It is a well-known technique for those skilled in the art that the high-grade ore is used as a core particle of pseudo particles without being crushed.
本願発明は、従来の当業者の常識に反し、当該高品位鉄鉱石をあえて破砕して使用することに特徴がある。即ち、本願発明は、前記ブラジル産鉱石が、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の融液浸透性を有するという特性を活用し、当該鉄鉱石を擬似粒子の核粒子としてではなく、擬似粒子への付着粉として使用することに特徴がある。 The invention of the present application is characterized in that the high-grade iron ore is intentionally crushed and used, contrary to conventional common knowledge of those skilled in the art. That is, the present invention utilizes the property that the Brazilian ore has a melt permeability of 4.0 mm or more into the iron ore powder, and the iron ore is used as a core particle of pseudo particles. And is characterized by being used as a powder adhering to pseudo particles.
焼結原料の混合・造粒で形成される擬似粒子の概念図を図４に示す。通常の焼結鉱原料を混合、造粒した場合を図４（Ａ）に示す。鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石をその他の原料と混合・造粒した場合を図４（Ｂ）に示す。 FIG. 4 shows a conceptual diagram of pseudo particles formed by mixing and granulating sintered raw materials. FIG. 4 (A) shows a case where ordinary sinter raw materials are mixed and granulated. Fig. 4 shows the case where iron ore with a melt penetration distance into ore powder of 4.0 mm or more and crushed particles with a particle size of 1 mm or more to 10 mass% or less is mixed and granulated with other raw materials. Shown in B).
焼結機における原料充填層への原料装入は、装入時の粗粒の転がりにより、通常、粗粒が下層に充填され、細粒が上層に充填される。通常の焼結鉱原料を混合、造粒した場合の図４（Ａ）では、それぞれの粒子は、粒径１ｍｍ以上の粒子を核として、その表面に１ｍｍ以下の微粒子が付着する。しかし、水分の管理が不十分な場合や、微粒子の量が不十分の場合、または、微粒子の付着力が弱く擬似粒子の強度が弱いことが原因で崩壊する場合等は、核粒子の表面に微粒子が付着されず、擬似粒子の造粒が不十分となって、微粒の鉄鉱石が焼結充填層に存在することになる。したがって、充填層上部は、細粒が装入され、擬似粒子が崩壊すると微粉が増え、通気性が阻害される。 In the raw material charging layer in the sintering machine, the coarse particles are usually filled in the lower layer and the fine particles are filled in the upper layer due to the rolling of the coarse particles during the charging. In FIG. 4A where ordinary sinter raw materials are mixed and granulated, each particle has a particle having a particle size of 1 mm or more as a nucleus, and fine particles of 1 mm or less adhere to the surface. However, if moisture management is inadequate, the amount of fine particles is insufficient, or if the fine particles have a weak adhesion and the strength of the pseudo particles is weak, the surface of the core particles Fine particles are not attached, and the pseudo particles are not sufficiently granulated, and fine iron ores are present in the sintered packed bed. Therefore, fine particles are inserted into the upper part of the packed bed, and when the pseudo particles are disintegrated, fine powder is increased and air permeability is inhibited.
一方、下方吸引型焼結機を用いた焼結鉱の製造においては、焼結パレット内の充填層下層の焼結原料は、下方に吸引される上層コークスの燃焼排ガスにより余熱され、熱が十分伝えられる。これに対し、充填層上層の鉱石は、排ガスにより余熱されないため熱が不足し、また、焼成後の焼結鉱は、上方より吸引された空気により急速冷却され、脆い焼結鉱となる。その結果、上層部における焼結鉱の成品歩留の低下および強度等の品質悪化をまねく。 On the other hand, in the production of sintered ore using a lower suction type sintering machine, the sintering raw material of the lower layer of the packed bed in the sintering pallet is preheated by the combustion gas of the upper coke sucked downward, and the heat is sufficient Reportedly. On the other hand, since the ore in the upper layer of the packed bed is not heated by the exhaust gas, the heat is insufficient, and the sintered ore after firing is rapidly cooled by the air sucked from above and becomes brittle sintered ore. As a result, the yield of the sintered ore product in the upper layer is lowered and the quality such as strength is deteriorated.
以上の如く、原料充填層の上層部は、微粉や細粒が存在し通気抵抗が大きく、かつ熱的に不十分な環境にあるため、それに対応した原料充填層上層部の擬似粒子の形成が必要である。 As described above, the upper layer portion of the raw material packed layer has fine powder and fine particles, has a large ventilation resistance, and is in a thermally insufficient environment. is necessary.
図４（Ｂ）は、融液浸透性が優れた鉄鉱石Ｂ（ｂ）を粒径１ｍｍ以上の粒子を１０質量％以下にした破砕品を通常の焼結鉱原料と混合、造粒した場合であり、鉄鉱石Ｂ（ｂ）は、粒径１ｍｍ以上の粒子が１０質量％以下に破砕されているため、核粒子になることはなく、粒径１ｍｍ以上の粒子表面に付着し、擬似粒子を形成する。この場合、鉄鉱石Ｂ（ｂ）の破砕粉は後述する如く、粒径１ｍｍ以上の粒子表面への付着力が強力である。その結果、鉄鉱石Ｂ（ｂ）が粒径１ｍｍ以上の粒子表面に付着した擬似粒子は、輸送又は装入による崩壊が少なく、充填層の上層部で、強固な擬似粒子を形成し、焼結充填層上層において微粉の鉄鉱石の存在が少なくなる。 Fig. 4 (B) shows a case where iron ore B (b) with excellent melt permeability is mixed and granulated with a normal sinter raw material and a crushed product in which particles having a particle size of 1 mm or more are reduced to 10 mass% or less. In the iron ore B (b), particles having a particle size of 1 mm or more are crushed to 10% by mass or less, so that the iron ore B (b) does not become a core particle and adheres to the particle surface having a particle size of 1 mm or more. Form. In this case, the crushed powder of iron ore B (b) has a strong adhesion to the surface of particles having a particle diameter of 1 mm or more, as will be described later. As a result, the pseudo particles in which the iron ore B (b) adheres to the particle surface having a particle diameter of 1 mm or more are less likely to collapse due to transportation or charging, and form strong pseudo particles in the upper layer portion of the packed bed, and are sintered. The presence of fine iron ore is reduced in the upper layer of the packed bed.
融液浸透性が優れた鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下の破砕品が核粒子表面に付着した鉱石は、融液浸透性が優れているから、１２００℃程度の比較的低温で、鉄含有原料中のＦｅ2Ｏ3と石灰石中のＣａＯとの反応でカルシウムフェライト（ＣａＯ−Ｆｅ2Ｏ３）の初期融液を生成する。当該初期融液は、擬似粒子の表面に形勢された融液浸透性の優れた鉄鉱石層に良く融液浸透し、この融液中に鉄鉱石または副原料中の成分が更に溶け込む同化反応を起こし焼結反応を進行させる。その結果、下層に比べ熱的に低温の条件にある原料充填層の上層部でも、強度が高く歩留のよい焼結鉱を製造することができる。 An ore in which a crushed product having a particle size of 1 mm or more and 10% by mass or less of iron ore having excellent melt permeability is attached to the surface of the core particle is excellent in melt permeability. At a low temperature, an initial melt of calcium ferrite (CaO—Fe 2 O 3 ) is generated by a reaction between Fe 2 O 3 in the iron-containing raw material and CaO in limestone. The initial melt is well infiltrated into the iron ore layer excellent in melt permeability formed on the surface of the pseudo particle, and an assimilation reaction in which components in the iron ore or the auxiliary material further dissolve in the melt. Awaken and advance the sintering reaction. As a result, it is possible to produce a sintered ore with high strength and good yield even in the upper layer portion of the raw material packed layer that is in a thermally low temperature condition as compared with the lower layer.
先願（特許文献８）では、融液浸透性が高い鉄鉱石は破砕されていないので、造粒性が低く、焼結機装入時および焼成過程で擬似造粒子が崩壊し、原料充填層内の通気性が低下し易いため、原料充填層全体の焼結性が悪化し、焼結鉱の成品歩留、強度、および、生産率は悪化する（特許文献８、段落「００９３」、図７、図８）。これに対し、本願発明は、融液浸透性が高い鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕しているので、破砕後の粉鉱石は、核粒子への付着力が強く造粒性が高く（本願の後述段落「００９０」）、融液浸透性の優れた鉱石が核粒子の表面に付着することで、カルシウムフェライト（ＣａＯ−Ｆｅ2Ｏ３）の初期融液が鉄鉱石と同化反応を引き起こし、原料充填層上部の全層厚に対する層厚比率で５〜１２％の範囲に制限されることなく５〜５０％の範囲に装入しても、強度と歩留の優れた焼結鉱を製造することができる。 In the prior application (Patent Document 8), since the iron ore having high melt permeability is not crushed, the granulation property is low, and the pseudo-granulated particles are collapsed at the time of charging the sintering machine and in the firing process. Since the air permeability in the inside tends to decrease, the sinterability of the entire raw material packed layer deteriorates, and the product yield, strength, and production rate of the sintered ore deteriorate (Patent Document 8, Paragraph “0093”, FIG. 7, FIG. 8). On the other hand, in the present invention, iron ore having high melt permeability is crushed to 10% by mass or less of particles having a particle size of 1 mm or more, so that the pulverized ore has strong adhesion to the core particles. Since the ore having high granulation property (paragraph “0090” described later in this application) and excellent melt permeability adheres to the surface of the core particles, the initial melt of calcium ferrite (CaO—Fe 2 O 3 ) becomes iron ore. Even if it causes an assimilation reaction with stone and is charged in the range of 5 to 50% without being limited to the range of 5 to 12% in the layer thickness ratio with respect to the total thickness of the upper part of the raw material packed layer, the strength and yield An excellent sintered ore can be produced.
ここで、前記鉱石を原料充填層上部に装入する場合に、全層厚に対する層厚比率で５％以上とするのは、層厚比率で５％以下の最上層は、熱不足が極めて厳しく効果が発揮できないからであり（特許文献８の段落「００８４」、図７、図８、段落「００９２」）、全層厚に対する層厚比率で５０％以下とするのは、原料充填層上部の熱不足対策が解消すれば目的が達成されるからである。 Here, when the ore is charged into the upper part of the raw material packed layer, the layer thickness ratio with respect to the total layer thickness is set to 5% or more. The uppermost layer with the layer thickness ratio of 5% or less has extremely severe heat shortage. This is because the effect cannot be exhibited (paragraph “0084”, FIG. 7, FIG. 8, paragraph “0092” of Patent Document 8), and the ratio of the layer thickness to the total layer thickness is 50% or less. This is because the purpose will be achieved if measures against heat shortage are eliminated.
次に、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の鉄鉱石が、更に、気孔率が０．０５ｃｃ/ｇ以上であることの技術的意義について説明する。 Next, the technical significance that the iron ore with a melt penetration distance into the iron ore powder of 4.0 mm or more has a porosity of 0.05 cc / g or more will be described.
気孔率は、水銀圧入法により、３３０００Ｐｓｉの圧力で測定した場合を言う。各種鉄鉱石の気孔率を表１に示す。鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した１種または２種以上からなる鉄鉱石では、カルシウムフェライト（ＣａＯ−Ｆｅ2Ｏ2）の初期融液が、気孔によく浸透し、気孔内で、鉄鉱石と同化反応を引き起こし、ボンドの強い焼結鉱を製造することができる。 The porosity means a case where measurement is performed at a pressure of 33000 Psi by a mercury intrusion method. Table 1 shows the porosity of various iron ores. In iron ore consisting of one or two or more kinds of iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more and crushed particles having a particle diameter of 1 mm or more to 10% by mass or less, calcium ferrite (CaO— The initial melt of Fe 2 O 2 ) penetrates well into the pores, causes an assimilation reaction with iron ore in the pores, and can produce a sintered ore having a strong bond.
鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石を、原料充填層上部の全層厚に対する層厚比率で５〜５０％の範囲に装入する方法としては、たとえば、原料二段装入法がある。その他原料用の第一のサージホッパーと、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子が１０質量％以下に破砕した鉄鉱石用の第二のサージホッパーを設け、第一のサージホッパーから原料を充填槽下層に装入した後、第二のサージホッパーから、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子が１０質量％以下に破砕した鉄鉱石を充填層上層に装入する方法である。 The iron ore with a melt penetration distance into the iron ore powder of 4.0 mm or more and crushed particles with a particle diameter of 1 mm or more to 10% by mass or less in a layer thickness ratio with respect to the total thickness of the upper part of the raw material packed bed As a method of charging in the range of 5 to 50%, for example, there is a raw material two-stage charging method. In addition, the first surge hopper for the raw material and the second for iron ore in which the melt penetration distance into the iron ore powder is 4.0 mm or more and particles having a particle size of 1 mm or more are crushed to 10 mass% or less. After the raw material is charged into the lower layer of the filling tank from the first surge hopper, the melt penetration distance from the second surge hopper into the iron ore powder is 4.0 mm or more, and In this method, iron ore in which particles having a diameter of 1 mm or more are crushed to 10% by mass or less is charged into the upper layer of the packed bed.
また、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石を、原料充填層上部の全層厚に対する層厚比率で５〜５０％の範囲に装入する方法としては、たとえば、原料粒度偏析装入法がある。
原料粒度偏析装入法は、原料充填層の上層側に細粒を、下層側に粗粒を偏析装入する方法であり、たとえば、サージホッパーからの原料の落下軌跡に、焼結ストランド幅方向に水平に（中島ら：CAMP-ISIJ,4(1991),116.）、又は、ストランドの走行方向に回転バーを設け（稲角ら：鉄と鋼,77(1991),63.）、バーの篩上の粗粒を原料充填層の下層に、篩下の細粒を原料充填層の上層に装入する方法である。
Moreover, the thickness of the iron ore having a melt penetration distance into the iron ore powder of 4.0 mm or more and crushed particles having a particle diameter of 1 mm or more to 10% by mass or less with respect to the total thickness of the upper part of the raw material packed bed As a method of charging in the range of 5 to 50% by ratio, for example, there is a raw material particle size segregation charging method.
The raw material particle size segregation charging method is a method in which fine particles are segregated into the upper layer side of the raw material packed layer and coarse particles are segregated into the lower layer side. Horizontally (Nakajima et al .: CAMP-ISIJ, 4 (1991), 116.) or a rotating bar in the running direction of the strand (Inagaku et al .: Iron and Steel, 77 (1991), 63.) In this method, the coarse particles on the sieve are charged in the lower layer of the raw material packed layer and the fine particles under the sieve are charged in the upper layer of the raw material packed layer.
本発明において、融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石は、細粒の表面に多く付着し擬似粒子を形成する。前記粒度偏析装入装置を用いることにより、融液浸透性が優れた破砕鉄鉱石が表面に付着した擬似粒子を比較的低温雰囲気にある原料充填層上層に装入し、焼成し難い粗粒鉄鉱石を比較的熱余裕のある原料充填層の下層に装入することで強度と歩留の優れた焼結鉱を製造することができる。ただし、この場合、融液浸透性が優れた破砕鉄鉱石が表面に付着した細粒の擬似粒子は、原料充填層の下層にも紛れ込むので、融液浸透性が優れた破砕鉄鉱石の全部が原料充填層の上層に装入されるものではない。 In the present invention, iron ore obtained by crushing particles having a melt penetration distance of 4.0 mm or more and a particle diameter of 1 mm or more to 10 mass% or less adheres to the surface of fine particles and forms pseudo particles. By using the particle size segregation charging apparatus, coarse particles of iron ore, which are charged with pseudo-particles with crushed iron ore with excellent melt permeability attached to the surface, are placed in the upper layer of the raw material packed bed in a relatively low temperature atmosphere and are difficult to fire. By inserting the stone into the lower layer of the raw material packed bed having a relatively large heat margin, a sintered ore having excellent strength and yield can be produced. However, in this case, the fine quasi-particles with crushed iron ore with excellent melt permeability attached to the surface are also mixed into the lower layer of the raw material packed bed, so that all of the crushed iron ore with excellent melt permeability is It is not charged in the upper layer of the raw material packed layer.
次に、本発明の実施例について説明するが、本発明はこれに限られるものではない。 Next, examples of the present invention will be described, but the present invention is not limited thereto.
（実施例１）
本発明は、複数銘柄の鉄鉱石のうちで、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子を１０質量％以下に破砕した鉄鉱石を使用することを特徴とするので、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕した効果を確認するための焼結鍋試験を行った。
(Example 1)
The present invention uses an iron ore having a melt penetration distance into an iron ore powder of 4.0 mm or more and crushed particles having a particle diameter of 1 mm or more to 10% by mass or less among a plurality of types of iron ores. Sintering pot test for confirming the effect of crushing iron ore with a melt penetration distance of 4.0 mm or more into iron ore powder to 10 mass% or less of particles with a particle size of 1 mm or more. Went.
鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の鉄鉱石であるＢ（ｂ）を粒径１ｍｍ以上の粒子が１０質量％以下にする破砕は、ボールミルで行った。 The crushing of B (b), which is an iron ore having a melt penetration distance of 4.0 mm or more into the iron ore powder, to 10% by mass or less of particles having a particle diameter of 1 mm or more was performed by a ball mill.
Ｂ（ｂ）鉱石の破砕前と破砕後の乾式粒度を図５に示す。破砕前のＢ（ｂ）は、平均粒度（ＭＳ）が２．６４ｍｍであるのに対し、破砕後のＢ（ｂ）は、平均粒度（ＭＳ）が０．５８ｍｍであり、粒径１ｍｍ以上の粒子が１０質量％以下であった。
粒度測定方法は、ＪＩＳＭ８７０６の７．４．３（−４０ｍｍ、＋１ｍｍ区分の手動篩分け）および、７．４．４（−１ｍｍ区分の手動篩分け）にしたがった。
The dry particle size before and after crushing B (b) ore is shown in FIG. B (b) before crushing has an average particle size (MS) of 2.64 mm, whereas B (b) after crushing has an average particle size (MS) of 0.58 mm and a particle size of 1 mm or more. The particles were 10% by mass or less.
The particle size measurement method was in accordance with JISM 8706 7.4.3 (-40 mm, manual sieving of +1 mm section) and 7.4.4 (manual sieving of -1 mm section).
Ｂ（ｂ）鉱石の破砕後の乾式粒度と湿式で測定した粒度の比較を図６に示す。湿式で測定した粒度は、−０．０２０ｍｍの微粒が約４０％を占めていた。
湿式粒度測定方法は、ＪＩＳＭ８７０６の７．４．６にしたがった。ただし、各篩区分毎に、超音波振動（３００Ｗ、４５ＫＨｅ、１５分間）を行い、サンプル取り扱いは、前記ＪＩＳ図３方法―１に従った。
FIG. 6 shows a comparison between the dry particle size after crushing B (b) ore and the particle size measured by the wet method. As for the particle size measured by the wet method, fine particles of -0.020 mm accounted for about 40%.
The wet particle size measurement method was in accordance with 7.4.6 of JISM 8706. However, ultrasonic vibration (300 W, 45 KHe, 15 minutes) was performed for each sieve section, and sample handling was in accordance with JIS FIG. 3 method-1.
Ｂ（ｂ）鉱石の破砕前と破砕後の付着力を図７に示す。ボールミルによる破砕によって、付着力が大幅に増加した。破砕したＢ（ｂ）鉱石の付着物の向上により、核粒子への表面に付着し、強固な擬似粒子が形成されるものと考えられる。
ここで、付着力の測定方法は以下による。破砕後鉄鉱石の場合は、１ｍｍ以下に破砕した鉄鉱石を直径３０ｍｍで高さ３０ｍｍの材質がステンレスの円筒に、充填層の気孔率が４５体積％（一定）となるような圧力で装入し、円筒を引き上げる力から付着力（ｇ/ｃｍ２）を算出した。破砕前鉄鉱石の場合は、破砕していない１ｍｍ以下鉱石を同様に測定した。鉱石を破砕すると破砕後の新しい破砕面により、付着力が向上したと考えられる。
The adhesion force before and after crushing B (b) ore is shown in FIG. Adhesion increased significantly due to ball milling. It is considered that the adhering matter of the crushed B (b) ore adheres to the surface to the core particle, and a strong pseudo particle is formed.
Here, the method for measuring the adhesive force is as follows. In the case of iron ore after crushing, iron ore crushed to 1 mm or less is charged into a stainless steel cylinder with a diameter of 30 mm and a height of 30 mm at a pressure such that the porosity of the packed bed is 45% by volume (constant). The adhesive force (g / cm 2 ) was calculated from the force pulling up the cylinder. In the case of iron ore before crushing, 1 mm or less ore which was not crushed was measured in the same manner. When the ore was crushed, it was thought that the adhesion was improved by the new crushing surface after crushing.
Ｂ（ｂ）鉱石を破砕しないで配合原料と混合、造粒した場合と、破砕した後に配合原料と混合、造粒した場合のＳＥＭによる擬似粒子の表面構造を図８に示す。図８（Ａ）で、Ｂ（ｂ）鉱石が破砕されていない場合は、核粒子の表面が微粉鉱石により被覆されていない箇所が観測されたが、Ｂ（ｂ）鉱石が破砕された図８（Ｂ）では、Ｂ（ｂ）鉱石により核粒子の表面が被覆されていることが観測された。 FIG. 8 shows the surface structure of pseudo particles by SEM when the B (b) ore is mixed and granulated with the blended raw material without crushing, and when mixed and granulated with the blended raw material after crushing. In FIG. 8 (A), when B (b) ore is not crushed, a portion where the surface of the core particles is not covered with fine ore was observed, but B (b) ore was crushed. In (B), it was observed that the surface of the core particle was covered with B (b) ore.
焼結鍋試験に用いた原料配合条件を表２に示す。充填槽への充填方法を図９に示す。ベース条件の図９図（Ａ）では、鉱石Ｂ（ｂ）、Ｐ（ｂ）、Ｐ（ａ）、Ｂ（ａ）、ＨＰＭを混合、造粒し、充填層全域（６００ｍｍ）に装入した。図９図（Ｂ）のテストにおいては、原料配合割合はベース条件と同じであるが、鉱石Ｂ（ｂ）は全量、粒径１ｍｍ以上の粒子が１０質量％以下に破砕したものを充填層の上層（３００ｍｍ）に集中させ、充填層の下層（３００ｍｍ）は、ベース条件の配合からＢ（ｂ）を除いたものを混合、造粒して装入した。 Table 2 shows the raw material blending conditions used in the sintering pot test. The filling method to a filling tank is shown in FIG. In FIG. 9A of the base condition, ores B (b), P (b), P (a), B (a), HPM are mixed, granulated, and charged to the entire packed bed (600 mm). . In the test of FIG. 9 (B), the raw material blending ratio is the same as the base condition, but the ore B (b) is the total amount of the ore B (b) having particles of 1 mm or more crushed to 10% by mass or less. The upper layer (300 mm) was concentrated, and the lower layer (300 mm) of the packed layer was mixed and granulated after removing B (b) from the blending of the base conditions.
焼結鉱石の強度を示す指標であるＳＩは、下記成品歩留測定後の焼結鉱の中から粒径：１０〜２５ｍｍの焼結鉱１０ｋｇを採取し、これを、２ｍ高さから４回落下させた後、落下前の焼結鉱の質量（ｋｇ）に対する、落下後の粒径：５ｍｍ以上の焼結鉱の質量（ｋｇ）の割合（質量％）を示す。 SI, which is an index indicating the strength of sintered ore, is obtained by collecting 10 kg of sintered ore having a particle size of 10 to 25 mm from the sintered ore after the following product yield measurement, and dropping this 4 times from a height of 2 m. The ratio (mass%) of the particle size after dropping: mass (kg) of sintered ore of 5 mm or more to the mass (kg) of sintered ore before dropping is shown.
焼結鉱の成品歩留は、焼結ケーキ（塊）を２ｍ高さから５回落下させた後、落下前の焼結ケーキ（塊）（但し、床敷鉱分を除く）の質量（ｋｇ）に対する、落下後の粒径：５ｍｍ以上の焼結鉱（但し、床敷鉱分を除く）の質量（ｋｇ）の割合（質量％）を示す。 The product yield of sintered ore is the mass of the sintered cake (lump) before dropping (excluding the floor ore) after dropping the sintered cake (lump) 5 times from 2m height ), The ratio (mass%) of the mass (kg) of sintered ore (excluding the bedding ore) of 5 mm or more after dropping.
この焼結鍋試験の焼成条件は、層厚：６００ｍｍ、吸引負圧：１４．７ＫＰａ、焼成時間：２７分とした。 The firing conditions of the sintering pot test were as follows: layer thickness: 600 mm, suction negative pressure: 14.7 KPa, firing time: 27 minutes.
焼結鍋試験結果を表３に示す。粒径１ｍｍ以上の粒子が１０質量％以下に破砕したＢ（ｂ）を上層（３００ｍｍ）に集中させることで、成品歩留が８．１％向上した。また、生産率と焼結強度（ＳＩ）も向上した。 The results of the sintering pot test are shown in Table 3. The product yield was improved by 8.1% by concentrating B (b), in which particles having a particle size of 1 mm or more were crushed to 10% by mass or less, in the upper layer (300 mm). Moreover, the production rate and the sintering strength (SI) were also improved.
（実施例２）
鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上の鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕した効果を実機で確認するため、６００ｍ２の実機焼結機において操業試験を行った。
試験に使用した原料配合条件は、焼結鍋試験に用いた配合と同じである。焼結機実機試験の概略設備を図１０に示す。図１０で、融液浸透距離が４．０ｍｍ以上の鉄鉱石Ｂ（ｂ）１をボールミル２に装入し破砕した。破砕前後の粒度を図１１に示す。破砕前の平均粒径１．９７ｍｍに対し、破砕後の平均粒径は０．６５ｍｍで、粒径１ｍｍ以上の粒子が１０質量％以下であった。Ｂ（ｂ）鉱石は破砕した後、Ｂ（ｂ）鉱石槽３に貯留した。図１０で、破砕したＢ（ｂ）は、他の原料槽４の原料とともに切り出され、ミキサー５で、混合・造粒され、粒径１ｍｍ以上の粗粒の表面に付着し、擬似粒子を形成し、擬似粒子は、原料ホッパー６に貯留した。原料ホッパー６から切り出された擬似粒子を、偏析装入装置（回転式スリットバー７）により焼結機パレット上に装入した。この場合、原料の粗粒は、回転式スリットバー７の篩上として原料充填層の下層に挿入され、その後、原料の細粒は充填層下層の上に上層として装入され、原料充填層が形成された。原料充填後、点火炉８で点火された後、焼結機ストランド９で焼結鉱が焼成された。
(Example 2)
In order to confirm the effect of crushing iron ore with a melt penetration distance of 4.0 mm or more into iron ore powder to 10 mass% or less of particles with a particle size of 1 mm or more, an operation test was conducted in a 600 m 2 actual machine sintering machine. Went.
The raw material mixing conditions used for the test are the same as those used for the sintering pot test. FIG. 10 shows the schematic equipment for the actual sintering machine test. In FIG. 10, iron ore B (b) 1 having a melt penetration distance of 4.0 mm or more was charged into a ball mill 2 and crushed. The particle size before and after crushing is shown in FIG. Compared to the average particle size of 1.97 mm before crushing, the average particle size after crushing was 0.65 mm, and particles having a particle size of 1 mm or more were 10% by mass or less. The B (b) ore was crushed and stored in the B (b) ore tank 3. In FIG. 10, the crushed B (b) is cut out together with the raw material of the other raw material tank 4, mixed and granulated by the mixer 5, and adhered to the surface of coarse particles having a particle diameter of 1 mm or more to form pseudo particles. The pseudo particles were stored in the raw material hopper 6. The pseudo particles cut out from the raw material hopper 6 were charged onto the sintering machine pallet by a segregation charging device (rotary slit bar 7). In this case, the raw material coarse particles are inserted into the lower layer of the raw material packed layer as the sieve of the rotary slit bar 7, and then the raw material fine particles are charged as the upper layer above the packed layer lower layer. Been formed. After filling the raw materials, the sintered ore was fired by the sintering machine strand 9 after being ignited by the ignition furnace 8.
原料の偏析状態を図１２に示す。０．２５〜１．０ｍｍの細粒の割合は、充填槽下層が２５％であるのに対し、充填槽上層は３５％であり、０．２５〜１．０ｍｍの細粒の割合が増加している。その結果、融液浸透距離が４．０ｍｍ以上の鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕した鉄鉱石の５８％が全層厚に対する層厚比率で５〜５０％の範囲の充填層上層に装入されていた。 The segregation state of the raw material is shown in FIG. The proportion of fine particles of 0.25 to 1.0 mm is 25% for the lower layer of the filling tank, whereas that of the upper layer of the filling tank is 35%, and the proportion of fine particles of 0.25 to 1.0 mm increases. ing. As a result, 58% of iron ore obtained by crushing iron ore having a melt penetration distance of 4.0 mm or more to particles having a particle diameter of 1 mm or more to 10 mass% or less is in a range of 5 to 50% in a layer thickness ratio with respect to the total thickness. It was charged in the upper layer of the packed bed.
実機操業試験結果を図１３に示す。ベース操業と比較して、融液浸透距離が４．０ｍｍ以上のＢ（ｂ）鉄鉱石を粒径１ｍｍ以上の粒子が１０質量％以下に破砕して、他の原料と混合、造粒後に原料充填層に偏析装入したテストの結果では、生産率、成品歩留の向上が図れた。 The actual machine operation test results are shown in FIG. Compared with the base operation, B (b) iron ore with a melt penetration distance of 4.0 mm or more is crushed to 10% by mass or less of particles with a particle size of 1 mm or more, mixed with other raw materials, and raw material after granulation As a result of the segregation charging in the packed bed, the production rate and product yield were improved.
下方吸引型焼結機を用いた焼結鉱の製造方法において、焼結原料に配合する各銘柄鉄鉱石の微粉部への融液浸透性を評価し、この評価結果に基づき、各銘柄鉄鉱石のうち、鉄鉱石粉中への融液浸透距離が４．０ｍｍ以上であり、かつ、粒径１ｍｍ以上の粒子が１０質量％以下に破砕した鉄鉱石を原料充填層上部に装入することにより、原料充填層上部の成品歩留および強度を改善し、焼結鉱の生産性を向上することができる。 In the manufacturing method of sintered ore using a downward suction type sintering machine, the melt penetration into the fine powder part of each brand iron ore to be blended with the sintering raw material was evaluated, and based on this evaluation result, each brand iron ore Among them, the melt penetration distance into the iron ore powder is 4.0 mm or more, and the iron ore crushed to 10% by mass or less of particles having a particle size of 1 mm or more is charged into the upper part of the raw material packed bed, The product yield and strength of the upper part of the raw material packed bed can be improved, and the productivity of the sintered ore can be improved.
１…鉄鉱石Ｂ（ｂ）、２…ボールミル、３…Ｂ（ｂ）鉱石槽、４…他の鉱石槽コークス、５…ミキサー、６…原料ホッパー、７…回転式スリットバー、８…点火炉、９…焼結機ストランド DESCRIPTION OF SYMBOLS 1 ... Iron ore B (b), 2 ... Ball mill, 3 ... B (b) Ore tank, 4 ... Other ore tank coke, 5 ... Mixer, 6 ... Raw material hopper, 7 ... Rotary slit bar, 8 ... Ignition furnace , 9 ... Sintering machine strand
Claims (4)
前記複数銘柄の鉄鉱石を銘柄毎に融液浸透性の評価試験を行い、鉄鉱石粉中への融液浸透距離の測定値に基づいて鉄鉱石粉中への融液浸透距離を測定する融液浸透距離測定工程と、
前記複数銘柄の鉄鉱石のうち、融液浸透距離が４．０mm以上で、かつ、結晶水が１．２６質量％以下の鉄鉱石の一部又は全部を、粒径１mm以上の粒子が１０質量％以下となるように破砕する鉱石破砕工程と、
前記破砕した鉄鉱石と、破砕していないその他の鉄鉱石、副原料、固体燃料、および返鉱とを混合、造粒して原料を製造する混合、造粒工程と、
前記混合、造粒した原料を、焼結パレット内に形成する原料充填層の上部に全層厚に対する層厚比率で上表面から５％〜上表面から５０％の範囲に装入する装入工程とを実施することを特徴とする焼結鉱の製造方法。 Mixing and granulating iron-containing raw materials containing multiple brands of iron ore, secondary raw materials, solid fuel, and returning ore to make sintered raw materials. After mixing and granulating the sintered raw materials, they are charged into a sintering pallet. In the method for producing sintered ore to be fired,
Perform the melt penetration evaluation test for each brand of iron ore for each brand and measure the melt penetration distance into the iron ore powder based on the measured value of the melt penetration distance into the iron ore powder. A distance measurement process;
Among the iron ores of multiple brands, a part or all of the iron ore having a melt penetration distance of 4.0 mm or more and a crystal water of 1.26% by mass or less , and particles having a particle diameter of 1 mm or more are 10 masses. Ore crushing step of crushing to less than
Mixing and granulating the crushed iron ore with other crushed iron ore, secondary raw materials, solid fuel, and returning ore to produce raw materials,
A charging step of charging the mixed and granulated raw material in a range of 5% from the upper surface to 50% from the upper surface at a layer thickness ratio with respect to the total layer thickness on the raw material packed layer formed in the sintering pallet. And a method for producing a sintered ore.
前記装入工程は、二段装入法により行われることを特徴とする焼結鉱の製造方法。 In the manufacturing method of the sintered ore of Claim 1,
The method for producing sintered ore, wherein the charging step is performed by a two-stage charging method.
前記装入工程は、前記混合、造粒した原料のうちの前記破砕した鉄鉱石を、焼結パレッ
ト内に形成する原料充填層の上部に全層厚に対する層厚比率で５〜５０％の範囲に、原料
粒度偏析装入法により装入することを特徴とする焼結鉱の製造方法。 In the manufacturing method of the sintered ore of Claim 1,
In the charging step, the crushed iron ore out of the mixed and granulated raw materials is in the range of 5 to 50% in the layer thickness ratio with respect to the total layer thickness at the upper part of the raw material packed layer formed in the sintering pallet. The method for producing a sintered ore characterized in that it is charged by a raw material particle size segregation charging method.
前記融液浸透距離が４．０ｍｍ以上の鉄鉱石が、更に、気孔率が０．０５ｃｃ/ｇ以上
であることを特徴とする焼結鉱の製造方法。 In the manufacturing method of the sintered ore in any one of Claims 1 thru | or 3,
The method for producing a sintered ore, wherein the iron ore having a melt penetration distance of 4.0 mm or more further has a porosity of 0.05 cc / g or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2010161945A JP5703616B2 (en) | 2010-07-16 | 2010-07-16 | Method for producing sintered ore |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2010161945A JP5703616B2 (en) | 2010-07-16 | 2010-07-16 | Method for producing sintered ore |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2012021213A JP2012021213A (en) | 2012-02-02 |
| JP5703616B2 true JP5703616B2 (en) | 2015-04-22 |
Family
ID=45775698
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2010161945A Active JP5703616B2 (en) | 2010-07-16 | 2010-07-16 | Method for producing sintered ore |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5703616B2 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62130229A (en) * | 1985-12-02 | 1987-06-12 | Sumitomo Metal Ind Ltd | Sintering operation method |
| JPH08176686A (en) * | 1994-12-20 | 1996-07-09 | Nippon Steel Corp | Production for sintered ore compounded at high ratio with high alumina iron ore |
| JP4422307B2 (en) * | 2000-08-21 | 2010-02-24 | 新日本製鐵株式会社 | Evaluation method of iron ore powder |
| JP4258429B2 (en) * | 2004-05-06 | 2009-04-30 | 住友金属工業株式会社 | Raw material charging method and raw material charging apparatus for sintering machine |
| JP4746410B2 (en) * | 2005-11-17 | 2011-08-10 | 新日本製鐵株式会社 | Method for producing sintered ore |
| JP5000366B2 (en) * | 2007-04-12 | 2012-08-15 | 新日本製鐵株式会社 | Method for producing sintered ore |
| WO2010032466A1 (en) * | 2008-09-17 | 2010-03-25 | 新日本製鐵株式会社 | Sintered ore manufacturing method |
-
2010
- 2010-07-16 JP JP2010161945A patent/JP5703616B2/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| JP2012021213A (en) | 2012-02-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5846049B2 (en) | Method for producing sintered ore | |
| JP5375742B2 (en) | Granulation method of sintering raw material | |
| JP6075231B2 (en) | Method for producing sintered ore | |
| TWI473882B (en) | Sintering raw materials for the adjustment of raw materials and sintering raw materials for powder | |
| JP6102463B2 (en) | Method for producing sintered ore | |
| JP6421666B2 (en) | Method for producing sintered ore | |
| JP4528362B2 (en) | Method for producing sintered ore | |
| JP4422307B2 (en) | Evaluation method of iron ore powder | |
| JP5935979B2 (en) | Method for producing pseudo-particles for producing sinter and method for producing sinter | |
| JP5703616B2 (en) | Method for producing sintered ore | |
| JP4392302B2 (en) | Method for producing sintered ore | |
| JP4580114B2 (en) | Pseudo particles for sintering | |
| TWI632241B (en) | Method for manufacturing sinter ore in carbon material | |
| JP6887717B2 (en) | Charcoal interior granulated particles for sinter production and sinter production method using them | |
| JP4867394B2 (en) | Non-calcined agglomerate for iron making | |
| JP4767388B2 (en) | Method for producing sintered ore with excellent high-temperature properties | |
| JP2007031818A (en) | Method for manufacturing sintered ore | |
| JP2018172761A (en) | Method for manufacturing sintered ore | |
| JP6331639B2 (en) | Sintering raw material blending method | |
| JP2009167466A (en) | Method for producing sintered ore | |
| JP2006104508A (en) | Method for manufacturing sintered ore | |
| JP3952871B2 (en) | Manufacturing method of high-strength sintered ore | |
| JP4077668B2 (en) | Sinter with excellent softening and melting properties | |
| JP2021025112A (en) | Method for manufacturing sintered ore | |
| JPH0598359A (en) | Manufacture of sintered ore |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20120809 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20131021 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20131119 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20140114 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20140902 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20141127 |
|
| A911 | Transfer of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20141204 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20150127 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20150209 |
|
| R151 | Written notification of patent or utility model registration |
Ref document number: 5703616 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R151 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |