JP7553179B2 - Method for pre-treating lump ore and method for operating a blast furnace - Google Patents
Method for pre-treating lump ore and method for operating a blast furnace Download PDFInfo
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本発明は、高炉に装入する前の塊鉱石に対して付着粉を除去する前処理を行う方法と、この前処理方法によって得られた塊鉱石を高炉に装入する高炉の操業方法に関する。 The present invention relates to a method for pre-treating lump ore to remove any adhering powder before it is charged into a blast furnace, and a method for operating a blast furnace in which the lump ore obtained by this pre-treating method is charged into the blast furnace.
特許文献１では、塊状鉱石を含む処理原料（鉄原料）を加熱処理して乾燥し、乾燥した処理原料を炉頂から炉内に装入する前に、篩選別処理によって、処理原料に付着した微粉鉱石を除去している。微粉鉱石を除去することにより、微粉鉱石によって炉内の空隙率が低下することを抑制し、炉内圧力の変動を抑制するようにしている。 In Patent Document 1, raw materials (iron raw materials) containing lump ore are heated and dried, and before the dried raw materials are charged into the furnace from the top, fine ore adhering to the raw materials is removed by screening. By removing the fine ore, it is possible to prevent the void ratio in the furnace from decreasing due to the fine ore, and to suppress fluctuations in the pressure in the furnace.
特許文献１では、高炉の上部に形成される処理原料層（鉱石層）の空隙率に着目し、この空隙率の低下を抑制するために、処理原料に付着している微粉鉱石を除去している。本発明者は、塊鉱石の種類によっては、塊鉱石に付着している付着粉を除去することにより、塊鉱石の高温還元性状を改善できることを見い出し、本発明を完成するに至った。高温還元性状とは、鉄原料の軟化が開始される炉下部における還元性状であり、高温還元性状を改善することにより、高炉の操業を改善することができる。 In Patent Document 1, attention is paid to the porosity of the processing raw material layer (ore layer) formed in the upper part of the blast furnace, and in order to prevent this porosity from decreasing, fine ore adhering to the processing raw material is removed. The inventors discovered that, depending on the type of lump ore, the high-temperature reduction properties of the lump ore can be improved by removing the adhering powder adhering to the lump ore, and thus completed the present invention. The high-temperature reduction properties are the reduction properties in the lower part of the furnace where the softening of the iron raw material begins, and by improving the high-temperature reduction properties, the operation of the blast furnace can be improved.
本発明である塊鉱石の前処理方法は、所定の組成を有する塊鉱石について、高炉に装入する前に、塊鉱石から直径が３ｍｍ以下の付着粉を除去する。この塊鉱石は、ＳｉＯ２の含有量が４.５質量％以下であり、Ａｌ２Ｏ３の含有量が３重量％以下であり、かつ、ＳｉＯ２の含有量に対するＡｌ２Ｏ３の含有量の比が０．５以上である。 The lump ore pretreatment method of the present invention removes adhering fines having a diameter of 3 mm or less from lump ore having a predetermined composition before the lump ore is charged into a blast furnace. The lump ore has a SiO2 content of 4.5 mass% or less, an Al2O3 content of 3 weight% or less, and a ratio of the Al2O3 content to the SiO2 content of 0.5 or more.
付着粉の除去を行う前の塊鉱石の質量に対して、塊鉱石に残存する付着粉の質量が占める割合が２質量％未満となるまで、付着粉の除去を行うことができる。また、付着粉の除去を行う前に、塊鉱石を乾燥することができる。 The adhering powder can be removed until the mass of the adhering powder remaining on the lump ore is less than 2% by mass of the mass of the lump ore before the adhering powder is removed. The lump ore can also be dried before the adhering powder is removed.
本発明である高炉の操業方法は、上述した前処理方法によって得られた塊鉱石を高炉に装入する。 The method of operating a blast furnace according to the present invention involves charging the lump ore obtained by the above-mentioned pretreatment method into the blast furnace.
本発明によれば、塊鉱石を炉内に装入する前に、上述した組成を有する塊鉱石から付着粉を除去することにより、炉内における塊鉱石の高温還元性状を改善することができる。 According to the present invention, by removing adhering powder from lump ore having the above-mentioned composition before the lump ore is charged into the furnace, the high-temperature reduction properties of the lump ore in the furnace can be improved.
本実施形態である塊鉱石の前処理方法では、所定の組成を有する塊鉱石について、塊鉱石を高炉に装入する前に、塊鉱石に付着した付着粉を除去する。また、本実施形態である高炉の操業方法では、上述した前処理方法によって得られた塊鉱石を高炉に装入する。塊鉱石は、焼結鉱やペレットと同様に鉄原料として用いられ、コークスと交互に炉頂から炉内に装入される。また、付着粉とは、直径が３ｍｍ以下の微粉鉱石である。 In the lump ore pretreatment method of this embodiment, fine particles adhering to lump ore having a predetermined composition are removed before the lump ore is charged into a blast furnace. In the blast furnace operation method of this embodiment, the lump ore obtained by the above-mentioned pretreatment method is charged into a blast furnace. The lump ore is used as an iron raw material like sintered ore and pellets, and is charged into the furnace from the top alternately with coke. The fine particles are fine ore having a diameter of 3 mm or less.
本実施形態が対象とする塊鉱石は、ＳｉＯ２の含有量が４．５質量％以下であり、Ａｌ２Ｏ３の含有量が３質量％以下であり、かつ、ＳｉＯ２の含有量に対するＡｌ２Ｏ３の含有量の質量比（すなわち、Ａｌ２Ｏ３の含有量をＳｉＯ２の含有量で除算した値、以下、質量比Ａ／Ｓという）が０．５［－］以上である。この組成を満たす塊鉱石としては、例えば、ピルバラブレンド鉱石が挙げられる。この塊鉱石について、付着粉を除去した後に高炉に装入することにより、高温（１１００℃～１２００℃）での塊鉱石の還元性状を改善することができる。 The lump ore targeted by this embodiment has a SiO2 content of 4.5 mass% or less, an Al2O3 content of 3 mass % or less, and a mass ratio of the Al2O3 content to the SiO2 content (i.e., the value obtained by dividing the Al2O3 content by the SiO2 content , hereinafter referred to as the mass ratio A/S) of 0.5 [-] or more. An example of a lump ore that satisfies this composition is Pilbara blend ore. By removing the attached powder from this lump ore and then charging it into a blast furnace, the reduction properties of the lump ore at high temperatures (1100°C to 1200°C) can be improved.
塊鉱石の高温還元性状は、塊鉱石自体（付着粉を除いたもの）の還元性と、塊鉱石に付着している付着粉の量に依存することが分かった。そして、塊鉱石自体の還元性及び付着粉の量の関係に着目したところ、上述した組成を満たす塊鉱石については、塊鉱石の高温還元性状を改善する上で、付着粉を除去することの意義が大きいことが分かった。以下、上述した塊鉱石の組成の意義について説明する。 It was found that the high-temperature reduction properties of lump ore depend on the reducibility of the lump ore itself (excluding adhering fines) and the amount of adhering fines adhering to the lump ore. When we looked at the relationship between the reducibility of the lump ore itself and the amount of adhering fines, we found that for lump ores that satisfy the above-mentioned composition, removing the adhering fines is very important in improving the high-temperature reduction properties of the lump ore. The significance of the above-mentioned lump ore composition is explained below.
塊鉱石自体の還元性は、ＳｉＯ２の含有量及びＡｌ２Ｏ３の含有量に依存する。図１に示すＦｅＯ－Ａｌ２Ｏ３－ＳｉＯ２の平衡状態図において、質量比Ａ／Ｓが０．５未満であるとき、１２００℃において２ＦｅＯ・ＳｉＯ２系融液が生成される領域がある。２ＦｅＯ・ＳｉＯ２系融液が低温で生成されると、塊鉱石の軟化収縮によって還元反応が遅延してしまう。一方、質量比Ａ／Ｓが０．５以上であれば、図１に示す平衡状態図において、２ＦｅＯ・ＳｉＯ２系融液が生成される領域が存在しない。このため、質量比Ａ／Ｓは０．５以上とする必要がある。 The reducibility of the lump ore itself depends on the SiO 2 content and the Al 2 O 3 content. In the equilibrium diagram of FeO-Al 2 O 3 -SiO 2 shown in FIG. 1, when the mass ratio A/S is less than 0.5, there is a region where 2FeO.SiO 2- based melt is generated at 1200°C. If the 2FeO.SiO 2 -based melt is generated at a low temperature, the reduction reaction is delayed due to the softening and shrinkage of the lump ore. On the other hand, if the mass ratio A/S is 0.5 or more, there is no region where 2FeO.SiO 2 -based melt is generated in the equilibrium diagram shown in FIG. 1. For this reason, the mass ratio A/S needs to be 0.5 or more.
また、質量比Ａ／Ｓが０．５以上であっても、ＳｉＯ２の含有量が増加すると、２ＦｅＯ・ＳｉＯ２系融液の生成量が増加することにより、塊鉱石が軟化収縮しやすくなり還元反応が遅延しやすくなる。この点を考慮して、本実施形態では、ＳｉＯ２の含有量を４．５質量％以下とした。ここで、ＳｉＯ２の含有量は、４．０質量％以下であることが好ましく、３．５質量％以下であることが更に好ましい。ＳｉＯ２の含有量は、ＪＩＳ Ｍ８２１４の規定に準じて測定することができる。 In addition, even if the mass ratio A/S is 0.5 or more, when the SiO2 content increases, the amount of 2FeO.SiO2 -based melt produced increases, which makes the lump ore more likely to soften and shrink, and the reduction reaction is more likely to be delayed. In consideration of this point, in this embodiment, the SiO2 content is set to 4.5 mass% or less. Here, the SiO2 content is preferably 4.0 mass% or less, and more preferably 3.5 mass% or less. The SiO2 content can be measured in accordance with the provisions of JIS M8214.
また、質量比Ａ／Ｓが０．５以上であっても、Ａｌ２Ｏ３の含有量が増加すると、２ＦｅＯ・ＳｉＯ２－Ａｌ２Ｏ３系融液の生成量が増加することにより、塊鉱石が軟化収縮しやすくなり還元反応が遅延しやすくなる。この点を考慮して、本実施形態では、Ａｌ２Ｏ３の含有量を３質量％以下とした。ここで、Ａｌ２Ｏ３の含有量は２．５質量％以下であることが好ましい。Ａｌ２Ｏ３の含有量は、ＪＩＳ Ｍ８８５６の規定に準じて測定することができる。 Furthermore, even if the mass ratio A/S is 0.5 or more, if the content of Al 2 O 3 increases, the amount of 2FeO.SiO2-Al 2 O 3 melt produced increases, which makes the lump ore more likely to soften and shrink, and the reduction reaction is more likely to be delayed. In consideration of this point, in this embodiment, the content of Al 2 O 3 is set to 3 mass% or less. Here, the content of Al 2 O 3 is preferably 2.5 mass% or less. The content of Al 2 O 3 can be measured in accordance with the provisions of JIS M8856.
塊鉱石から付着粉を除去する処理（以下、除去処理という）としては、公知の処理を適宜採用することができる。この除去処理では、少なくとも一部の付着粉を塊鉱石から除去すればよい。除去処理では、例えば、塊鉱石を水洗することにより付着粉を除去したり、塊鉱石に振動を与えることにより付着粉を除去したりすることができる。振動によって付着粉を除去する場合には、加熱処理などにより塊鉱石を事前に乾燥することが好ましい。塊鉱石を乾燥することにより、付着粉を除去しやすくなる。また、高炉に装入される塊鉱石について、加熱処理などにより塊鉱石の水分量が所定量以下となるまで乾燥すれば、塊鉱石を高炉に装入したときに、水分の蒸発熱を低減して炉内温度が低下することを抑制できる。したがって、高炉の安定操業の上では、乾燥処理が行われた塊鉱石を高炉に装入することが好ましい。 As a process for removing the adhering powder from the lump ore (hereinafter referred to as the removal process), a known process can be appropriately adopted. In this removal process, at least a part of the adhering powder may be removed from the lump ore. In the removal process, for example, the adhering powder may be removed by washing the lump ore with water, or by vibrating the lump ore. When removing the adhering powder by vibration, it is preferable to dry the lump ore in advance by a heat treatment or the like. Drying the lump ore makes it easier to remove the adhering powder. In addition, if the lump ore to be charged into the blast furnace is dried until the moisture content of the lump ore is reduced to a predetermined amount or less by a heat treatment or the like, the heat of evaporation of the moisture can be reduced when the lump ore is charged into the blast furnace, and the temperature inside the furnace can be prevented from dropping. Therefore, for the stable operation of the blast furnace, it is preferable to charge the lump ore that has been dried into the blast furnace.
塊鉱石から付着粉を除去する操作を定量的に表すために、次の指標を用いる。
除去処理を行う前の塊鉱石の質量（付着粉を含む） Ｗｔ
除去処理で除去される付着粉の質量 Ｗｐｄ
除去処理後の塊鉱石に残留する付着粉の質量 Ｗｐｒ
付着粉の総質量（＝Ｗｐｄ＋Ｗｐｒ） Ｗｐｔ
The following index is used to quantitatively express the operation of removing the adhering fines from the lump ore.
Mass of lump ore before removal treatment (including attached powder) Wt
Mass of adhering powder removed by removal process Wpd
Mass of powder remaining on lump ore after removal process Wpr
Total mass of attached powder (= Wpd + Wpr) Wpt
除去処理を行った後において、塊鉱石に付着したままとなる付着粉の残存割合Ｒｐｒは、２質量％未満であることが好ましい。 After the removal process, it is preferable that the remaining proportion of adhering powder Rpr that remains attached to the lump ore is less than 2 mass%.
ここに、残存割合Ｒｐｒとは、下記（１）式で定義する。
Ｒｐｒ＝１００×（Ｗｐｒ／Ｗｔ） ・・・（１）
Here, the remaining ratio Rpr is defined by the following formula (1).
Rpr=100×(Wpr/Wt)...(1)
ここに、Ｗｐｒ＝Ｗｐｔ－Ｗｐｄであるから、Ｒｐｒは下記（２）式から計測できる。
Ｒｐｒ＝１００×（（Ｗｐｔ－Ｗｐｄ）／Ｗｔ） ・・・（２）
Here, since Wpr=Wpt-Wpd, Rpr can be calculated from the following equation (2).
Rpr=100×((Wpt-Wpd)/Wt)...(2)
なお、質量Ｗｔの代わりに付着粉を除いた塊鉱石の質量Ｗо（Ｗｔ－Ｗｐｄ、或いは、Ｗｔ－Ｗｐｔ）を用い、残存割合Ｒｐｒ（Ｒｐｒ＝１００×（Ｗｐｒ／Ｗо））を規定することもできる。 In addition, the mass of the lump ore excluding adhering powder, Wо (Wt-Wpd or Wt-Wpt), can be used instead of the mass Wt to determine the remaining ratio Rpr (Rpr = 100 x (Wpr/Wо)).
塊鉱石から除去する付着粉の質量Ｗｐｄは、除去処理の時間に依存する。すなわち、除去処理時間が長いほど、質量Ｗｐｄが多くなるため、除去処理時間及び質量Ｗｐｄの間には、所定の相関関係が成り立つ。この相関関係を予め求めておけば、除去処理時間を調整することにより、質量Ｗｐｄを調整することができる。そして、質量Ｗｔ，Ｗｐｔを予め測定しておけば、上記（２）式によって、除去処理時間を調整することにより、残存割合Ｒｐｒを調整することができる。このため、残存割合Ｒｐｒが２質量％未満となるまでの除去処理時間を予め決めておき、この時間だけ除去処理を行えば、残存割合Ｒｐｒを２質量％未満とすることができる。 The mass Wpd of the adhering powder removed from the lump ore depends on the time of the removal process. In other words, the longer the removal process time, the greater the mass Wpd, and so a certain correlation is established between the removal process time and the mass Wpd. If this correlation is determined in advance, the mass Wpd can be adjusted by adjusting the removal process time. If the masses Wt and Wpt are measured in advance, the remaining ratio Rpr can be adjusted by adjusting the removal process time using the above formula (2). Therefore, by determining in advance the removal process time until the remaining ratio Rpr becomes less than 2 mass%, and performing the removal process for this time, the remaining ratio Rpr can be made less than 2 mass%.
上述した組成を有する塊鉱石については、残存割合Ｒｐｒが低いほど、高温還元性状を改善しやすくなるが、塊鉱石の高温還元率Ｒ１１００をより高くする上では、残存割合Ｒｐｒを２質量％未満とすることが好ましい。高温還元率Ｒ１１００は、鉄原料の被還元性の指標となる値であり、１１００℃における鉄原料の還元率である。 For lump ore having the above-mentioned composition, the lower the residual ratio Rpr, the easier it is to improve the high-temperature reduction properties, but in order to increase the high-temperature reduction ratio R1100 of the lump ore, it is preferable to set the residual ratio Rpr to less than 2 mass%. The high-temperature reduction ratio R1100 is a value that serves as an index of the reducibility of the iron raw material, and is the reduction ratio of the iron raw material at 1100°C.
４種類の塊鉱石Ａ（ピルバラブレンド）、塊鉱石Ｂ（ローブ）、塊鉱石Ｃ（ゴア）、塊鉱石Ｄ（ヤンディ）について、残存割合Ｒｐｒ及び高温還元率Ｒ１１００の関係を調べた。各塊鉱石Ａ～Ｄとしては、篩い分けによって直径が１０～１５ｍｍの粒度に調整した。下記表１には、各塊鉱石Ａ～Ｄにおける化学成分及び質量比Ａ／Ｓと総付着粉割合Ｒｐｔとを示す。 The relationship between the residual ratio Rpr and the high-temperature reduction ratio R1100 was investigated for four types of lump ore, namely, lump ore A (Pilbara Blend), lump ore B (Robe), lump ore C (Gore), and lump ore D (Yandi). Each lump ore A to D was adjusted to a particle size of 10 to 15 mm in diameter by sieving. Table 1 below shows the chemical components and mass ratio A/S and the total attached powder ratio Rpt for each lump ore A to D.
ここに、全鉄Ｔ．Ｆｅは、ＪＩＳ Ｍ８２１２の規定に準じて測定し、結晶水ＣＷは、カールフィッシャー法によって測定した。 Here, total iron (T.Fe) was measured according to the JIS M8212 standard, and water of crystallization (CW) was measured by the Karl Fischer method.
総付着粉割合Ｒｐｔとは、上述した総付着粉の質量Ｗｐｔを水洗処理で除去された粉の質量と見做し（Ｗｐｔ＝Ｗｐｄ，Ｗｐｒ＝０）、その水洗処理を行う前の塊鉱石の質量Ｗｔに対する、水洗処理で除去された粉の質量の割合（Ｒｐｔ＝１００×（Ｗｐｄ／Ｗｔ））である。 The total adhering powder ratio Rpt is the ratio of the mass of the powder removed by the water washing process to the mass of the lump ore before the water washing process, Wt (Rpt = 100 x (Wpd/Wt)), assuming that the mass of the total adhering powder Wpt described above is the mass of the powder removed by the water washing process (Wpt = Wpd, Wpr = 0).
総付着粉割合Ｒｐｔの測定では、まず、水洗処理を行う前に、塊鉱石（付着粉を含む）の質量Ｗｔを測定する。次に、水洗処理を行うことにより、塊鉱石に付着している、すべての付着粉を除去し、除去された付着粉の質量Ｗｐｄ（＝Ｗｐｔ）を測定する。これにより、総付着粉割合Ｒｐｔが求められる。 When measuring the total adhering powder ratio Rpt, first, the mass Wt of the lump ore (including the adhering powder) is measured before performing the water washing process. Next, all the adhering powder adhering to the lump ore is removed by performing the water washing process, and the mass Wpd (= Wpt) of the removed adhering powder is measured. This gives the total adhering powder ratio Rpt.
残存割合Ｒｐｒ及び高温還元率Ｒ１１００の関係については、残存割合Ｒｐｒを異ならせながら、残存割合Ｒｐｒ毎に高温還元率Ｒ１１００を測定した。高温還元率Ｒ１１００は、論文「焼結鉱の軟化溶融性状評価法の開発」（細谷ら，鉄と鋼，Ｖｏｌ．８３（１９９７），９７－１０２）に記載された測定方法に基づいて測定し、その結果から、温度が１１００℃に到達した時点の還元率を高温還元率Ｒ１１００とした。この論文では焼結鉱を用いているが、焼結鉱の代わりに塊鉱石を用いて、高温還元率Ｒ１１００を測定することができる。還元率Ｒ１１００の測定条件は上記論文に記載されたとおりであり、高温還元率Ｒ１１００の算出方法も公知であるため、ここでは詳細な説明を省略する。 Regarding the relationship between the residual ratio Rpr and the high-temperature reduction ratio R1100 , the high-temperature reduction ratio R1100 was measured for each residual ratio Rpr while varying the residual ratio Rpr. The high-temperature reduction ratio R1100 was measured based on the measurement method described in the paper "Development of a method for evaluating the softening and melting properties of sintered ore" (Hosoya et al., Iron and Steel, Vol. 83 (1997), 97-102), and the reduction ratio at the time when the temperature reached 1100°C was taken as the high-temperature reduction ratio R1100 based on the result. Although sintered ore is used in this paper, the high-temperature reduction ratio R1100 can be measured by using lump ore instead of sintered ore. The measurement conditions for the reduction ratio R1100 are as described in the above paper, and the calculation method for the high-temperature reduction ratio R1100 is also known, so a detailed explanation will be omitted here.
各塊鉱石Ａ～Ｄの残存割合Ｒｐｒを異ならせる処理について、以下に説明する。 The process of varying the remaining ratio Rpr of each lump ore A to D is described below.
まず、乾燥器内に各塊鉱石Ａ～Ｄを設置し、１１０℃の雰囲気で１日中放置した。この乾燥処理の後、篩目が２．７ｍｍである篩が設置されたロータップ振盪器を用いて各塊鉱石Ａ～Ｄを振盪させることにより、各塊鉱石Ａ～Ｄから付着粉を除去した。そして、各塊鉱石Ａ～Ｄから除去した付着粉について、除去割合Ｒｐｄを測定した。 First, each lump ore A to D was placed in a dryer and left in an atmosphere at 110°C for a day. After this drying process, each lump ore A to D was shaken using a rotary tap shaker equipped with a sieve with 2.7 mm mesh to remove the adhering powder from each lump ore A to D. The removal rate Rpd was then measured for the adhering powder removed from each lump ore A to D.
除去割合Ｒｐｄとは、ロータップ振盪器によって振盪を行う前の塊鉱石の質量（上述した質量Ｗｔに相当する）に対して、振盪によって除去された付着粉の質量Ｗｐｄの割合（Ｒｐｄ＝１００×（Ｗｐｄ／Ｗｔ））である。振盪を行う前の塊鉱石の質量Ｗｔを測定するとともに、振盪によって除去された付着粉の質量Ｗｐｄを測定すれば、除去割合Ｒｐｄが求められる。 The removal rate Rpd is the ratio of the mass Wpd of the adhering powder removed by shaking to the mass of the lump ore before shaking with the rotary tap shaker (corresponding to the mass Wt described above) (Rpd = 100 x (Wpd/Wt)). The removal rate Rpd can be determined by measuring the mass Wt of the lump ore before shaking and the mass Wpd of the adhering powder removed by shaking.
上述したように、質量Ｗｐｄ（言い換えれば、除去割合Ｒｐｄ）は、ロータップ振盪器の振盪時間（上述した除去処理時間）に依存するため、振盪時間を調整することにより、質量Ｗｐｄ（除去割合Ｒｐｄ）を調整することができる。除去割合Ｒｐｄを調整すれば、塊鉱石に付着したままとなる付着粉の残存割合Ｒｐｒを調整することができる。残存割合Ｒｐｒは、上記（２）式から分かるように、総付着粉割合Ｒｐｔから除去割合Ｒｐｄを減算した値となる。各塊鉱石Ａ～Ｄについて、複数の残存割合Ｒｐｒを設定しておき、残存割合Ｒｐｒ毎に、各塊鉱石Ａ～Ｄの高温還元率Ｒ１１００を測定することにより、残存割合Ｒｐｒ及び高温還元率Ｒ１１００の関係が得られる。 As described above, since the mass Wpd (in other words, the removal ratio Rpd) depends on the shaking time of the rotary tap shaker (the above-mentioned removal processing time), the mass Wpd (removal ratio Rpd) can be adjusted by adjusting the shaking time. By adjusting the removal ratio Rpd, the remaining ratio Rpr of the adhering powder that remains attached to the lump ore can be adjusted. As can be seen from the above formula (2), the remaining ratio Rpr is a value obtained by subtracting the removal ratio Rpd from the total adhering powder ratio Rpt. A plurality of remaining ratios Rpr are set for each of the lump ores A to D, and the high-temperature reduction ratio R 1100 of each of the lump ores A to D is measured for each remaining ratio Rpr, whereby the relationship between the remaining ratio Rpr and the high-temperature reduction ratio R 1100 can be obtained.
図２には、各塊鉱石Ａ～Ｄについて、残存割合Ｒｐｒ及び高温還元率Ｒ１１００の関係（実測値）を示す。図２から分かるように、残存割合Ｒｐｒが低下するほど、高温還元率Ｒ１１００が上昇する。ここで、残存割合Ｒｐｒの低下量に対する高温還元率Ｒ１１００の上昇量の割合、言い換えれば、図２に示す各近似直線の傾きは、塊鉱石Ａ～Ｄの種類に応じて異なることが分かった。 Fig. 2 shows the relationship (actual measurement value) between the residual ratio Rpr and the high-temperature reduction ratio R1100 for each lump ore A to D. As can be seen from Fig. 2, the higher the residual ratio Rpr, the higher the high-temperature reduction ratio R1100 . Here, it was found that the ratio of the increase in the high-temperature reduction ratio R1100 to the decrease in the residual ratio Rpr, in other words, the slope of each approximation line shown in Fig. 2, differs depending on the type of lump ore A to D.
図２によれば、塊鉱石Ａについて、残存割合Ｒｐｒの低下量に対する高温還元率Ｒ１１００の上昇量の割合が最も大きくなった。塊鉱石Ａ～Ｄのうち、実施形態で説明した組成を満たす塊鉱石は、塊鉱石Ａだけとなる。このことから、塊鉱石の高温還元性状を向上させる上では、塊鉱石Ａについて除去処理を行うことが効果的であることが分かる。 2, the ratio of the increase in the high-temperature reduction ratio R1100 to the decrease in the residual ratio Rpr was the largest for the lump ore A. Among the lump ores A to D, the only lump ore that satisfies the composition described in the embodiment is the lump ore A. From this, it can be seen that performing the removal treatment for the lump ore A is effective in improving the high-temperature reduction properties of the lump ore.
残存割合Ｒｐｒの低下量に対する高温還元率Ｒ１１００の上昇量の割合だけに着目すると、塊鉱石Ａ，Ｄは同様の挙動を示すが、高温還元率Ｒ１１００に着目すると、塊鉱石Ａの高温還元率Ｒ１１００は塊鉱石Ｄの高温還元率Ｒ１１００よりも高くなるため、高温還元性状については、塊鉱石Ｄよりも塊鉱石Ａのほうが優れていることになる。また、塊鉱石Ａについて、残存割合Ｒｐｒを２質量％未満にすれば、塊鉱石Ａ～Ｄのなかで、高温還元率Ｒ１１００が最も高くなる。このことから、塊鉱石Ａから付着粉を除去するときには、残存割合Ｒｐｒを２質量％未満とすることが好ましいことが分かる。 When only the ratio of the increase in the high-temperature reduction rate R 1100 to the decrease in the residual rate Rpr is considered, the lump ores A and D show similar behavior. However, when the high-temperature reduction rate R 1100 is considered, the high-temperature reduction rate R 1100 of the lump ore A is higher than that of the lump ore D. Therefore, the high-temperature reduction property of the lump ore A is superior to that of the lump ore D. Furthermore, when the residual rate Rpr of the lump ore A is set to less than 2 mass%, the high-temperature reduction rate R 1100 of the lump ore A is the highest among the lump ores A to D. From this, it is understood that when removing the adhering powder from the lump ore A, it is preferable to set the residual rate Rpr to less than 2 mass%.
尚、前述の２質量％未満とした塊鉱石Ａの好ましい残存割合Ｒｐｒは、付着粉の除去処理を行う前の塊鉱石Ａの質量Ｗｔに対する、除去処理後の塊鉱石Ａに残留する付着粉の質量Ｗｐｒの比率（上記（１）式）で表記した数値である。付着粉を除いた塊鉱石の質量Ｗо（すなわち、Ｗｔ－Ｗｐｔ）に対して残存割合Ｒｐｒを定義した場合では、塊鉱石Ａの総付着粉割合Ｒｐｔが８．９質量％であるから、残存割合Ｒｐｒは２．２質量％（＝２質量％／（１－（８．９／１００）））未満であることが好ましい。
The preferable remaining ratio Rpr of the lump ore A, which is less than 2 mass%, is a value expressed by the ratio (expressed by the above formula (1)) of the mass Wpr of the adhering fine remaining on the lump ore A after the adhering fine removal process to the mass Wt of the lump ore A before the adhering fine removal process. When the remaining ratio Rpr is defined with respect to the mass Wo of the lump ore excluding the adhering fine (i.e., Wt-Wpt), the total adhering fine ratio Rpt of the lump ore A is 8.9 mass%, so that the remaining ratio Rpr is preferably less than 2.2 mass% (=2 mass%/(1-(8.9/100))).
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006291255A (en) | 2005-04-07 | 2006-10-26 | Sumitomo Metal Ind Ltd | Blast furnace operation method |
| JP2008261016A (en) | 2007-04-12 | 2008-10-30 | Nippon Steel Corp | Method for producing sintered ore |
| JP2009149969A (en) | 2007-11-29 | 2009-07-09 | Jfe Steel Corp | Removal method of adhering powder of lump ore |
| JP2017110241A (en) | 2015-12-14 | 2017-06-22 | Ｊｆｅスチール株式会社 | Blast furnace charging raw material supply apparatus and method |
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| JP4634887B2 (en) * | 2005-08-03 | 2011-02-16 | 新日本製鐵株式会社 | Blast furnace operation method |
| JP5505188B2 (en) * | 2010-08-12 | 2014-05-28 | Ｊｆｅスチール株式会社 | Bulk ore processing method |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006291255A (en) | 2005-04-07 | 2006-10-26 | Sumitomo Metal Ind Ltd | Blast furnace operation method |
| JP2008261016A (en) | 2007-04-12 | 2008-10-30 | Nippon Steel Corp | Method for producing sintered ore |
| JP2009149969A (en) | 2007-11-29 | 2009-07-09 | Jfe Steel Corp | Removal method of adhering powder of lump ore |
| JP2017110241A (en) | 2015-12-14 | 2017-06-22 | Ｊｆｅスチール株式会社 | Blast furnace charging raw material supply apparatus and method |
Non-Patent Citations (1)
| Title |
|---|
| 佐々木 貴広他２名，塊鉱石の成分及び品質が高炉操業に及ぼす影響，材料とプロセス，Ｖｏｌ．２１（２００８），８８９頁 |
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