JPH0429721B2 - - Google Patents
Info
- Publication number
- JPH0429721B2 JPH0429721B2 JP23425984A JP23425984A JPH0429721B2 JP H0429721 B2 JPH0429721 B2 JP H0429721B2 JP 23425984 A JP23425984 A JP 23425984A JP 23425984 A JP23425984 A JP 23425984A JP H0429721 B2 JPH0429721 B2 JP H0429721B2
- Authority
- JP
- Japan
- Prior art keywords
- limonite
- component
- feo
- sintering
- ore
- 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.)
- Expired
Links
- 239000002994 raw material Substances 0.000 claims description 20
- 238000005245 sintering Methods 0.000 claims description 18
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 15
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 14
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 13
- 239000008187 granular material Substances 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 3
- 239000013078 crystal Substances 0.000 claims description 2
- 230000009467 reduction Effects 0.000 description 15
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 14
- 229910052595 hematite Inorganic materials 0.000 description 13
- 239000011019 hematite Substances 0.000 description 13
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 13
- 238000000227 grinding Methods 0.000 description 10
- 238000005469 granulation Methods 0.000 description 8
- 230000003179 granulation Effects 0.000 description 8
- 238000002425 crystallisation Methods 0.000 description 5
- 230000008025 crystallization Effects 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 238000010298 pulverizing process Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 2
- 235000011941 Tilia x europaea Nutrition 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000004571 lime Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- UHZZMRAGKVHANO-UHFFFAOYSA-M chlormequat chloride Chemical compound [Cl-].C[N+](C)(C)CCCl UHZZMRAGKVHANO-UHFFFAOYSA-M 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000010410 dusting Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Landscapes
- Manufacture And Refinement Of Metals (AREA)
Description
（産業上の利用分野）
本発明は、高アルミナ褐鉄鉱を原料の一部とし
て使用する焼結鉱製造方法に関する。
（従来の技術）
銑鉄製造用の溶鉱炉に装入される原料として
CaO濃度の高い石灰焼結鉱が広く使用されている
が、日本の製鉄業においては、品質の安定した焼
結鉱を得るために種々の性質を有する鉄鉱石をブ
レンドして焼結原料として使用するのが一般であ
る。このようにブレンドされる鉄鉱石のうち高ア
ルミナ褐鉄鉱は、焼結性に悪影響をおよぼす因子
を種々有しており、特に、耐還元粉化性について
は、第２図に示すように、鉱石のAl2O3成分の増
加、結晶水成分の増加にしたがつて悪化する傾向
がある。本発明で対象とするアルミナ褐鉄鉱は、
Al2O3を2.3wt％以上および結晶水（CW）を
2.0wt％以上含有するものである。
上記のような高アルミナ褐鉄鉱の耐還元粉化性
悪化要因に対しては、多くの対策や原料処理方法
が提案されている。たとえば、特開昭52−49905
号公報においては、種々の鉱石原料を一度に混合
造粒するのではなく、造粒性の悪い原料のみを別
途予備混合造粒することにより通気性の改善を図
る方法が示されている。しかしながら、この方法
は通気性の改善を目的に成されたものであり、焼
結鉱の品質改善を達成するには到つていない。
一般に、石灰焼結鉱の還元粉化は、ヘマタイト
がマグネタイトに還元される時に膨張し、応力を
発生することが主原因とされているが、特に、ヘ
マタイト鉱石が未反応で残存するヘマタイト（一
次ヘマタイト）よりも、焼結反応から発生するヘ
マタイト（二次ヘマタイト）の方がその発生応力
が大きいことが知られている。さらに、二次ヘマ
タイトの中でもAl2O3成分を多く含むヘマタイト
は、発生膨張応力が高く、還元粉化を生じさせ易
い鉱物と言われている。本発明で使用されるアル
ミナ褐鉄鉱は、そのうち褐鉄鉱部分において、焼
結反応直前には結晶水が分解して多孔質な鉱石と
なり、焼結反応が良好であるため、一次ヘマタイ
トを残存させず二次ヘマタイトを形成させる傾向
がある。その上、高さAl2O3成分を含有している
ため、発生膨張応力の大きい高Al2O3含有の二次
ヘマタイトを形成し、耐還元粉化性を大幅に悪化
させている。
（発明が解決しようとする問題点）
耐還元粉化性を改善するために、FeO成分や
MgO成分を添加して二次ヘマタイトの生成を抑
制する方法が考えられる。しかしながら、ヘマタ
イトを完全に抑制するためには多量のFeO成分や
MgO成分を添加する必要があり、その結果、焼
結鉱全体のFeO成分やMgO成分が上昇し、焼結
鉱の被還元性が大幅に悪化することとなる。
そこで、本発明の目的は、被還元性を損なうこ
となく、耐還元粉化性を改善することができる、
高アルミナ褐鉄鉱を原料の一部として使用する焼
結鉱製造方法を提供することにある。
（問題点を解決するための手段）
上記問題点を解決し、上記目的を達成するため
に、本発明は、Al2O3を2.3wt％以上および結晶
水を2.0wt％以上含むアルミナ褐鉄鉱を焼結原料
の一部として使用し、CaO成分が6.5〜12.0wt％
の自溶性焼結鉱を製造する方法において、上記ア
ルミナ褐鉄鉱を5.8〜20.0wt％のFeO成分存在下
に事前予備混合造粒し、得られた予備混合造粒物
を他の残りの焼結原料とともに混合または造粒し
た後焼結することを特徴とするものである。
本発明によれば、第１ａ図に示すように、
Al2O3成分が2.3wt％以上、結晶水が2.0wt％以上
の高アルミナ褐鉄鉱の１種または数種に高FeO成
分鉱石、返鉱等の予備混合造粒物原料Ａが配合さ
れ、ミキサー１により事前混合造粒される。事前
混合造粒に際しては、FeO成分が5.8〜20.0wt％、
最も好ましくは12wt％前後となるように成分調
整される。事前混合造粒には、好ましくは高
MgO成分鉱石がさらに配合される。事前混合造
粒におけるFeO成分を5.8wt％以上としたのは、
第３図に示すように、事前混合造粒物中のFeO成
分濃度が5.8wt％以上になると、耐還元粉化性が
顕著に改善されるのに対し、5.8wt％未満の場合
には、耐還元粉化性の改善がほとんど見られない
からである。また、FeO成分の上限を20.0wt％と
したのは、被還元性を損なわないためである。
MgO成分鉱石を添加する場合には、予備混合造
粒物中のMgO成分濃度が1.0〜5.0wt％となるの
が好ましい。これは、第４図に示されるように、
MgO成分濃度が1.0wt％以上となると、耐還元粉
化性の改善が顕著となるからである。上限は、被
還元性を低下させないためのものである。
事前混合造粒を行なうためのミキサー１として
は、ドラムタイプ、パンペレタイザータイプ等の
ものが使用される。造粒性の点からは、パンペレ
タイザータイプのものが好ましい。
事前混合粒度構成は、２mm以下のものが80wt
％以上あることが望ましい。これは、第５図から
も明らかなように、細粒化することにより造粒物
の成分的均一性が促進され、耐還元粉化性がより
改善されるからである。
事前混合造粒物は、他の残り焼結原料Ｂととも
にミキサー２において混合造粒され、焼結機３に
供給されて焼結される。
あるいは、事前混合造粒物は、第１ｂ図に示す
ように、他の残り焼結原料のみを別途ミキサー
１′により予備混合造粒したものと合わせて、焼
結機３に供給するようにしてもよい。この場合、
２種の造粒物は別途ミキサー（図示せず）により
混合することが望ましいが、焼結パレツト装入ま
での搬送過程を利用して混合してもよい。
（作 用）
上記のように事前処理を施した焼結原料を焼結
機に装入すると、事前に予備混合造粒された造粒
物は、CaOと反応して融液を作り、冷却されて鉱
物を形成するが、造粒物近傍のFeO、MgO、
Al2O3成分は他の部分と比べて高くなるが、高
Al2O3成分含有の二次ヘマタイトの形成は抑制さ
れる。一方、事前混合造粒に関与しない原料側付
近では、FeO、MgO、Al2O3成分は低下し、二次
ヘマタイトは形成されてもAl2O3含有濃度は低
い。このように、結局、焼結鉱全体としては、均
一系のものと比べて、耐還元粉化性が改善され
る。一方、耐還元粉化性の改善のために使用され
るFeO成分、MgO成分量は一定範囲に限定され
ているので、被還元性は実質的に低下しない。
（実施例）
第１表に示す性状の原料を用い、第２表に示す
条件で焼結鍋テストを実施した。焼成操業条件は
一定となるように行なつた。結果を、第３表、第
４表および第３図〜第５図に示す。なお、従来法
としては、第６図に示すように、全焼結鉱原料を
ミキサー２′で一挙に混合、造粒後、焼結機３に
て焼結する方法を採用した。
(Industrial Application Field) The present invention relates to a method for producing sintered ore using high alumina limonite as part of the raw material. (Conventional technology) As a raw material charged into a blast furnace for producing pig iron.
Lime sintered ore with a high CaO concentration is widely used, but in the Japanese steel industry, iron ore with various properties is blended and used as a sintering raw material in order to obtain sintered ore with stable quality. It is common to do so. Among the iron ores blended in this way, high alumina limonite has various factors that adversely affect sinterability, and in particular, regarding reduction powdering resistance, as shown in Figure 2, the ore's It tends to worsen as the Al 2 O 3 component increases and the crystal water component increases. The alumina limonite targeted by the present invention is
2.3wt% or more of Al 2 O 3 and water of crystallization (CW)
It contains 2.0wt% or more. Many countermeasures and raw material processing methods have been proposed for the above-mentioned factors that deteriorate the reduction powdering resistance of high alumina limonite. For example, JP-A-52-49905
The publication discloses a method of improving air permeability by separately pre-mixing and granulating only raw materials with poor granulation properties, rather than mixing and granulating various ore raw materials at once. However, this method was developed for the purpose of improving air permeability, and has not yet achieved improvement in the quality of sintered ore. Generally, the main cause of the reduction and pulverization of lime sinter is that hematite expands and generates stress when it is reduced to magnetite. It is known that the stress generated in hematite (secondary hematite) generated from a sintering reaction is greater than that in hematite (secondary hematite). Furthermore, among secondary hematites, hematite containing a large amount of Al 2 O 3 components is said to be a mineral that generates high expansion stress and is easily reduced and powdered. In the alumina limonite used in the present invention, immediately before the sintering reaction, the crystallization water decomposes in the limonite part to form a porous ore, and because the sintering reaction is good, the primary hematite does not remain and the secondary It has a tendency to form hematite. Furthermore, since it contains a high Al 2 O 3 component, secondary hematite containing high Al 2 O 3 is formed which generates a large expansion stress, and the resistance to reduction and pulverization is significantly deteriorated. (Problem to be solved by the invention) In order to improve reduction powdering resistance, FeO components and
A possible method is to add an MgO component to suppress the formation of secondary hematite. However, in order to completely suppress hematite, large amounts of FeO components and
It is necessary to add an MgO component, and as a result, the FeO component and MgO component of the sintered ore as a whole increase, and the reducibility of the sintered ore significantly deteriorates. Therefore, an object of the present invention is to improve reduction resistance to powdering without impairing reducibility.
An object of the present invention is to provide a method for producing sintered ore using high alumina limonite as part of the raw material. (Means for Solving the Problems) In order to solve the above problems and achieve the above objects, the present invention provides an alumina limonite containing 2.3 wt% or more of Al 2 O 3 and 2.0 wt% or more of crystallization water. Used as part of sintering raw material, CaO component is 6.5-12.0wt%
In the method for producing self-fusing sintered ore, the alumina limonite is premixed and granulated in the presence of 5.8 to 20.0wt% FeO component, and the obtained premixed granules are mixed with other remaining sintering raw materials. It is characterized in that it is mixed or granulated together with other materials and then sintered. According to the invention, as shown in FIG. 1a,
One or more types of high alumina limonite containing 2.3 wt% or more of Al 2 O 3 components and 2.0 wt% or more of crystallization water are mixed with premixed granulated raw material A such as high FeO component ore and return ore, and then mixed with a mixer. Premix granulation is performed by 1. During premix granulation, the FeO component is 5.8 to 20.0wt%,
Most preferably, the composition is adjusted to about 12 wt%. For premix granulation, preferably high
MgO component ore is further blended. The FeO component in pre-mix granulation was set to 5.8wt% or more because
As shown in Figure 3, when the FeO component concentration in the pre-mixed granules is 5.8wt% or more, the reduction powdering resistance is significantly improved, whereas when it is less than 5.8wt%, This is because almost no improvement in reduction powdering resistance is observed. Furthermore, the reason why the upper limit of the FeO component is set at 20.0 wt% is to not impair reducibility.
When adding MgO component ore, it is preferable that the MgO component concentration in the premixed granules is 1.0 to 5.0 wt%. As shown in Figure 4, this
This is because when the MgO component concentration is 1.0 wt% or more, the improvement in resistance to reduction and powdering becomes remarkable. The upper limit is for not reducing the reducibility. As the mixer 1 for premixing and granulation, a drum type, pan pelletizer type, or the like is used. From the viewpoint of granulation properties, a pan pelletizer type is preferred. The pre-mixed particle size composition is 80wt for particles of 2mm or less.
% or more is desirable. This is because, as is clear from FIG. 5, by making the particles finer, the compositional uniformity of the granulated product is promoted and the resistance to reduction and pulverization is further improved. The premixed granules are mixed and granulated together with other remaining sintering raw materials B in a mixer 2, and then supplied to a sintering machine 3 where they are sintered. Alternatively, the premixed granules may be supplied to the sintering machine 3 together with other remaining sintering raw materials separately premixed and granulated using a mixer 1', as shown in FIG. 1b. Good too. in this case,
Although it is desirable to mix the two types of granules using a separate mixer (not shown), they may also be mixed using the transportation process up to charging the sintered pallet. (Function) When the sintering raw material that has been pretreated as described above is charged into the sintering machine, the granules that have been premixed and granulated in advance react with CaO to form a melt and are cooled. However, FeO, MgO, and
Although the Al 2 O 3 component is higher than other parts,
The formation of secondary hematite containing the Al 2 O 3 component is suppressed. On the other hand, near the raw material side that does not participate in premix granulation, FeO, MgO, and Al 2 O 3 components decrease, and even if secondary hematite is formed, the Al 2 O 3 content concentration is low. In this way, the sintered ore as a whole has improved resistance to reduction and pulverization compared to a homogeneous one. On the other hand, since the amounts of FeO and MgO components used to improve resistance to reduction and powdering are limited to a certain range, reducibility does not substantially decrease. (Example) Using raw materials having the properties shown in Table 1, a sintering pot test was conducted under the conditions shown in Table 2. The firing operation conditions were kept constant. The results are shown in Table 3, Table 4, and Figures 3 to 5. As a conventional method, as shown in FIG. 6, all the sintered ore raw materials were mixed at once in a mixer 2', granulated, and then sintered in a sintering machine 3.
【表】【table】
【表】【table】
【表】【table】
【表】【table】
【表】【table】
【表】
（発明の効果）
上記したように、本発明によれば、特定範囲の
FeO成分存在下に高アルミナ褐鉄鉱を事前混合造
粒することにより、他の品質を悪化させることな
く、耐還元粉化性および生産性を改善することが
できる。[Table] (Effects of the invention) As described above, according to the present invention, a specific range of
By premixing and granulating high alumina limonite in the presence of FeO components, reduction dusting resistance and productivity can be improved without deteriorating other qualities.
第１ａ図および第１ｂ図は本発明による原料処
理フローを示す図、第２図は鉱石の結晶水−
Al2O3成分と還元粉化との関係を示すグラフ、第
３図は予備混合造粒物のFeO成分濃度と還元粉化
性との関係を示すグラフ、第４図は予備混合造粒
物のMgO成分濃度と還元粉化性との関係を示す
グラフ、第５図は高アルミナ褐鉄鉱の粒度変更テ
スト結果を示すグラフ、第６図は従来の原料処理
フローを示す図である。
１，１′，２，２′…ミキサー、３…焼結機。
Figures 1a and 1b are diagrams showing the raw material processing flow according to the present invention, and Figure 2 is a diagram showing the crystallization water of ore.
A graph showing the relationship between Al 2 O 3 components and reduction powdering. Figure 3 is a graph showing the relationship between the FeO component concentration and reduction powdering property of the premixed granules. Figure 4 is a graph showing the relationship between the premixed granules. Figure 5 is a graph showing the results of a particle size change test for high alumina limonite, and Figure 6 is a diagram showing the conventional raw material processing flow. 1, 1', 2, 2'... mixer, 3... sintering machine.
Claims (1)
以上含む高アルミナ褐鉄鉱を焼結原料の一部とし
て使用し、CaO成分が6.5〜12.0wt％の自溶性焼
結鉱を製造する方法において、上記アルミナ褐鉄
鉱を5.8〜20wt％のFeO成分存在下に事前予備混
合造粒し、得られた予備混合造粒物を他の残りの
焼結原料とともに混合および／または造粒した後
焼結することを特徴とする高アルミナ褐鉄鉱を用
いる焼結鉱製造方法。1 2.3wt% or more of Al 2 O 3 and 2.0wt% of crystal water
In a method for producing self-soluble sinter with a CaO component of 6.5 to 12.0 wt% using high alumina limonite containing the above as part of the sintering raw material, the above alumina limonite is mixed in the presence of a FeO component of 5.8 to 20 wt%. A method for producing sintered ore using high alumina limonite, which comprises premixing and granulating in advance, mixing and/or granulating the obtained premix granules with other remaining sintering raw materials, and then sintering. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23425984A JPS61113729A (en) | 1984-11-06 | 1984-11-06 | Manufacture of sintered ore using high alumina limonite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23425984A JPS61113729A (en) | 1984-11-06 | 1984-11-06 | Manufacture of sintered ore using high alumina limonite |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61113729A JPS61113729A (en) | 1986-05-31 |
| JPH0429721B2 true JPH0429721B2 (en) | 1992-05-19 |
Family
ID=16968166
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23425984A Granted JPS61113729A (en) | 1984-11-06 | 1984-11-06 | Manufacture of sintered ore using high alumina limonite |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61113729A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0730417B2 (en) * | 1989-10-17 | 1995-04-05 | 新日本製鐵株式会社 | Manufacturing method of sinter for blast furnace using high goethite ore |
| JP5617167B2 (en) * | 2009-02-12 | 2014-11-05 | Ｊｆｅスチール株式会社 | Method for producing sintered ore for blast furnace |
| CN102787234B (en) * | 2012-08-23 | 2014-06-25 | 武钢集团昆明钢铁股份有限公司 | High-ratio sintering method for limonite |
-
1984
- 1984-11-06 JP JP23425984A patent/JPS61113729A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61113729A (en) | 1986-05-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |