JPS6227526A - Pretreatment of starting material for sintering - Google Patents

Abstract

PURPOSE:To improve the gas permeability of starting materials for sintering during sintering without using quick lime and to manufacture sintered ore having superior characteristic at a low cost by adding hyperfine ore as a pseudo- pelletizing agent to iron ore as a starting material when sintered ore for a blast furnace is manufactured. CONSTITUTION:When sintered ore for a blast furnace is manufactured, hyperfine iron ore as a pseudo-pelletizing agent is added to fine iron ore as a starting material by 20-50% in place of expensive quick lime. The radio of the hyperfine iron ore to the fine iron ore in average grain size is <=0.04. The ores are pelletized and the resulting pellets are sintered together with coke, etc. The gas permeability of the starting materials for sintering during sintering is improved without using expensive quick lime and sintered ore having superior characteristics can be manufactured at a low cost.

Description

【発明の詳細な説明】 ［発明の利用分野］ 本発明は高炉の主要装入物である焼結鉱の製造工程のう
ちの一工程である焼結原料の事前処理法に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for pre-treating a sintered raw material, which is one step in the manufacturing process of sintered ore, which is the main charge of a blast furnace.

［従来技術］ 焼結鉱は、粉鉱石１石灰石、返鉱、粉コークス、生石灰
等をドラムミキサーで混合し、造粒を行った後、焼結機
のパレット上に所定の厚さ層状に装入して原料層とし、
これを焼成することにより製造されるものである。上記
造粒された焼結原料がパレット上に装入された直後に、
原料層上部へ着火され、その後パレットの下方からファ
ンによって吸引される空気によって焼成が下部の方に進
行する。[Prior art] Sintered ore is produced by mixing powdered ore, limestone, return ore, coke powder, quicklime, etc. in a drum mixer, granulating it, and then stacking it on a pallet of a sintering machine in layers to a predetermined thickness. into the raw material layer,
It is manufactured by firing this. Immediately after the granulated sintered raw material is loaded onto the pallet,
The upper part of the raw material layer is ignited, and then the firing progresses toward the lower part by air sucked in by a fan from below the pallet.

焼結鉱の生産性はパレット上に装入された着火前の原料
層の通気性に強く依存するためその通気性を良好にする
ことが要求されている。Since the productivity of sintered ore strongly depends on the air permeability of the raw material layer charged on the pallet before ignition, it is required to improve the air permeability.

ところで、この通気性は焼結原料の擬似粒子化性の改善
に伴って向上する。Incidentally, this air permeability improves as the pseudo-particle formation property of the sintering raw material improves.

焼結原料の擬似粒子化性は、ドラムミキサーなどの造粒
機で造粒することによる、擬似粒子の形成される程度で
表されている。擬似粒子とは第４図に示すように、核鉱
石１の周囲に微粉状の粉コークス２、微粉鉱石３および
造滓剤４が付着して形成される粒子状の物体を指す、具
体的には。The ability to form pseudo-particles of a sintered raw material is expressed by the degree to which pseudo-particles are formed by granulation with a granulator such as a drum mixer. As shown in FIG. 4, pseudo particles refer to particulate objects formed by fine coke powder 2, fine ore powder 3, and slag forming agent 4 attached around core ore 1. teeth.

０．５ｍｍ以下の微粉粒子が１．０　＋＊ｍ以上の核粒
子に付着する程度で擬似粒子化性を表している。第４図
は造粒前の真粒子の粒度分布と造粒後の擬似粒子の粒度
分布を示したグラフである。第５図から０．５−型具下
の微粉粒子が１．０謬−以上の核粒子に付着する程度、
すなわち擬似粒子化性が分る。The extent to which fine powder particles of 0.5 mm or less adhere to core particles of 1.0 +* m or more indicates pseudo-particulate property. FIG. 4 is a graph showing the particle size distribution of true particles before granulation and the particle size distribution of pseudo particles after granulation. From Fig. 5, the extent to which the fine powder particles under the 0.5-mold mold adhere to the core particles of 1.0- or more,
In other words, the property of forming pseudo-particles can be seen.

しかるに、従来は、擬似粒子化性を促進し、その結果と
して原料層の通気性を確保するための方法として、生石
灰等のバインダーを粉体の原料に１〜２重量パ°−セン
ト添加して造粒していた。However, in the past, a binder such as quicklime was added to the powder raw material in an amount of 1 to 2% by weight in order to promote pseudo-particulate properties and thereby ensure air permeability of the raw material layer. It was granulating.

しかし生石灰は高価であるため、従来の方法ではコスト
アップになってしまう。However, since quicklime is expensive, conventional methods increase costs.

［発明の目的］ 本発明の目的は、生石灰を使用せずに焼結原料の擬似粒
子化性を促進し、通気性の良い焼結原料を作成できる焼
結原料の事前処理法を提供するにある。[Object of the Invention] An object of the present invention is to provide a method for pre-processing sintered raw materials that can promote pseudo-granulation properties of sintered raw materials and create sintered raw materials with good air permeability without using quicklime. be.

［発明の概要］ 上記目的は、粉鉱石を主成分とする焼結原料に、該焼結
原料との平均粒径比が０．０４以下である微粉鉱石を擬
似粒子化剤として、混合した後、造粒を行うことを特徴
とする焼結原料の事前処理方法によって達成される。[Summary of the Invention] The above object is to produce a sintered raw material containing fine ore as a main component, after mixing fine ore having an average particle size ratio of 0.04 or less with the sintering raw material as a pseudo-granulating agent. , is achieved by a method for pre-processing sintering raw materials, which is characterized by performing granulation.

なお、微粉鉱石の配合量は、擬似粒子化性の悪い焼結原
料の０．５ｍｍ以下の配合割合以上が好ましい、また、
本発明の対象となる粉鉱石、微粉鉱石としでは、たとえ
ば、鉄鉱石、マンガン鉱石、亜鉛鉱石、鉛鉱石などがあ
げられる。In addition, the blending amount of fine ore is preferably at least 0.5 mm of the sintering raw material with poor pseudo-particulate property, and
Examples of fine ore and fine ore to be used in the present invention include iron ore, manganese ore, zinc ore, and lead ore.

［発明の実施例］ 以下に本発明の実施例を比較例とともに示す。[Embodiments of the invention] Examples of the present invention are shown below along with comparative examples.

なお、以下に述べる原料の擬似粒子化性の評価方法であ
るが、擬似粒子径の大きい焼結原料はど原料層の通気性
が向上することから、原料層の通気性によって擬似粒子
化性を評価することができる。そして原料層の通気性は
（１）式のＪＰＵによって評価できることから、焼結原
料の擬似粒子化性は（１）式のＪＰＵによって評価でき
る。In addition, in the method for evaluating the pseudo-granulation property of raw materials described below, since the sintered raw material with a large pseudo-particle size improves the permeability of the raw material layer, the pseudo-particulation property can be evaluated by the air permeability of the raw material layer. can be evaluated. Since the air permeability of the raw material layer can be evaluated by the JPU of equation (1), the pseudo-particulate property of the sintered raw material can be evaluated by the JPU of the equation (1).

ｈ　　　０９６ ＪＰ、Ｕ＝ｖ・（−）　　・・・・・・・・・（１）Δ
　ｐ ここで、Ｖは塔内に焼結原料を入れていない時の気体の
通気速度である空塔波速Ｃｍ／■ｉｎ　）、ｈは塔内に
入れた焼結原料層の厚さく＋５ｉＩ）　、Δｐは焼結原
料層における圧力損失（ｍｍＨ２０）をそれぞれ示す。h 096 JP, U=v・(-) ・・・・・・・・・(1)Δ
p Here, V is the gas ventilation velocity when no sintering raw material is placed in the column, which is the superficial wave velocity Cm/■in), and h is the thickness of the sintering raw material layer placed in the column + 5iI), Δp represents the pressure loss (mmH20) in the sintered raw material layer.

（比較例） 最初に焼結原料の鉱石の平均粒径に対し、０．０３倍以
下の平均粒径の鉱石を擬似粒子化剤として添加しない条
件での焼結原料の通気性を測定した。(Comparative Example) First, the air permeability of the sintering raw material was measured under the condition that ore having an average particle size of 0.03 times or less of the average particle size of the ore of the sintering raw material was not added as a pseudo-granulating agent.

実験は焼結原料の鉱石を３１以下の石灰石粉、３■以下
の粉コークスとともに、直径３００重腸１長さ２８０■
の小型のドラムミキサーで造粒した後、直径　１０５■
、高さ４００＋ｓｍの小型の焼結鍋に造粒した焼結原料
を入れ（１）式により通気性ＪＰＵを求めた。実験に使
用した鉱石は、Ａ：マウントφニューマン（Ｍｔ、Ｎｅ
ｗｍａｎ　）　、　Ｂ　：　Ｏ−ブリバー（Ｒｏｂｅｒ
ｉｖｅｒ）　、Ｃ：ヤンピーサウンド（Ｙ　ａｍｐｉＳ
　ｏｕｎｄ）で、それぞれの粒径分布は同一で、第１表
に示す粒度分布をしている。In the experiment, the ore used as the raw material for sintering was used together with limestone powder of 31 mm or less and coke powder of 3 mm or less, with a diameter of 300 mm and a length of 280 mm.
After granulation with a small drum mixer, the diameter is 105cm.
The granulated sintering raw material was placed in a small sintering pot with a height of 400+sm, and the air permeability JPU was determined using equation (1). The ore used in the experiment was A: Mount φ Newman (Mt, Ne
wman), B: O-Bliver (Rober
iver), C:YampiS
ound), and each particle size distribution is the same and has the particle size distribution shown in Table 1.

鉱石Ａ、Ｂ、Ｃを焼結原料とした原料層の通気性を第６
図に示す０通気性はＡ、Ｂ、Ｃの順に低くなることが分
る。なお、ＪＰＵは水分量によって変化するため、水分
量との関係で示しである。The air permeability of the raw material layer using ores A, B, and C as raw materials for sintering is
It can be seen that the zero air permeability shown in the figure decreases in the order of A, B, and C. Note that since JPU changes depending on the amount of water, it is shown in relation to the amount of water.

（実施例） 比較例においては通気性の悪い鉱石Ｃに対し、鉱石Ａの
微粉を添加して、擬似粒子化による通気性向上を検討し
た。(Example) In a comparative example, fine powder of ore A was added to ore C, which has poor air permeability, and improvement of air permeability by forming pseudo particles was investigated.

通気性の評価は（２）式に示す微粉鉱石添加時のＪＰＵ
と、微粉鉱石無添加時のＪＰＵとの比である相対通気度
により行い、添加する鉱石の粒径の評価は（３）式に示
す微粉鉱石の平均粒径と、焼結原料の平均粒子径の比で
ある平均粒子径比とした。The evaluation of air permeability is the JPU when fine ore is added as shown in equation (2).
The particle size of the added ore is evaluated based on the average particle size of the fine ore shown in equation (3) and the average particle size of the sintering raw material. The average particle diameter ratio was defined as the ratio of

・・・・・・・・・（２） ・・・・・・・・・（３） まず、平均粒子径比０．０１２．０．０２．０．０３と
。・・・・・・・・・(2) ・・・・・・・・・(3) First, the average particle diameter ratio is 0.012.0.02.0.03.

０．１２（比較例）の４種につき、鉱石Ａの微粉鉱石の
添加量を変化させて相対通気度を測定した。その結果を
第１図および第２図に示す、第１図に示すように微粉゛
鉱石の添加に伴って相対通気度が増加し、約３５％で最
大値を示すことがわかる。この相対通気度の最大値が平
均粒子径比によって異なっていることもわかる。0.12 (comparative example), the relative air permeability was measured by changing the amount of fine ore added of ore A. The results are shown in FIGS. 1 and 2. As shown in FIG. 1, it can be seen that the relative air permeability increases with the addition of fine ore and reaches a maximum value at about 35%. It can also be seen that the maximum value of this relative air permeability differs depending on the average particle size ratio.

そして、平均粒子径比０．０１２．０．０２．０．０３
については、微粉鉱石の添加量が２０〜５０重量％の範
囲（実施例の範囲）において良好な相対通気度を示して
いる。And the average particle size ratio 0.012.0.02.0.03
shows good relative air permeability when the amount of fine ore added is in the range of 20 to 50% by weight (range in the examples).

第２図では、相対通気度の最大値を縦軸にとり、平均粒
子径比を横軸にとっである。第２図から、平均粒径比が
０．０３倍以下になると相対通気度が急増し、鉱石Ｃの
擬似粒子化性が飛躍的に向上することが分る。In FIG. 2, the maximum value of relative air permeability is plotted on the vertical axis, and the average particle diameter ratio is plotted on the horizontal axis. From FIG. 2, it can be seen that when the average particle size ratio becomes 0.03 times or less, the relative permeability increases rapidly, and the pseudo-grainability of ore C dramatically improves.

これは粒子と粒子の粒径差が大きいほど、両者の付着頻
度が高くなるためであるが、焼結原料の場合には最大粒
子径に限界があるため、粒子径を小さくすることによっ
て粒径差を大きくする必要がある。This is because the larger the difference in particle size between particles, the more frequently they will adhere to each other, but in the case of sintered raw materials, there is a limit to the maximum particle size, so by reducing the particle size, It is necessary to increase the difference.

（第２実施例） 鉱石Ｃよりも通気性のよい、すなわち擬似粒子化性のよ
い鉱石Ａ鉱石Ｂを被添加鉱石とし、鉱石Ａの微粉を添加
した。添加量は３５重量％、平均粒子径比は０．０１２
である。(Second Example) Ore A Ore B, which has better air permeability than Ore C, that is, has better pseudo-granulation properties, was used as the additive ore, and fine powder of Ore A was added. Addition amount is 35% by weight, average particle size ratio is 0.012
It is.

その結果を第３図に示す、第３図かられかるように、相
対通気度は、鉱石Ａの場合は、１．２、鉱石Ｂの場合は
　１．６と良好であった。The results are shown in FIG. 3. As can be seen from FIG. 3, the relative air permeability was good at 1.2 for ore A and 1.6 for ore B.

なお、以上の実施例では、添加微粉鉱石として鉱石Ａの
微粉鉱石の例を示したが、鉱石Ｂの微粉鉱石でもよい、
しかし、鉱石Ｃのように擬似粒子化性の悪いものは効果
がない。In addition, in the above example, an example of fine ore of ore A was shown as the added fine ore, but fine ore of ore B may also be used.
However, ore C, which has poor pseudo-grainability, is not effective.

［発明の効果］ 焼結鉱の原料の事前処理工程において、焼結原料の平均
粒径に対し平均粒径が０．０３倍以下の鉱石を擬似粒子
化剤として焼結原料に添加すると、焼結原料を造粒した
後の焼結工程において、原料層の通気性が向上する。[Effect of the invention] In the pre-treatment process of the raw material for sintered ore, if ore with an average particle size of 0.03 times or less than the average particle size of the sintered raw material is added as a pseudo-granulating agent to the sintered raw material, In the sintering step after granulating the sintering raw material, the air permeability of the raw material layer is improved.

従って従来のように擬似粒子化性を向上させるために用
いていた高価な生石灰を焼結原料に添加する必要が無く
なり、焼結鉱の製造時のコストが下がるという効果が生
じる。Therefore, it is no longer necessary to add expensive quicklime to the sintering raw material, which was conventionally used to improve pseudo-grainability, resulting in the effect of lowering the manufacturing cost of sintered ore.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は原料層の通気性に及ぼす微粉鉱石Ａの添加の影
響を示すグラフである。第２図は原料層の通気性に及ぼ
す微粉鉱石と焼結原料との平均粒子径比の影響を示すグ
ラフである。第３図は各種被添加鉱石に対する相対通気
度を示すグラフである。第４図は擬似粒子の模式図であ
る。第５図は造粒による粒度分布の変化を示すグラフで
ある。 第６図は鉱石Ａ、Ｂ、Ｃに微粉鉱石を添加しない条件で
の通気性を表わすグラフである。 第１図 位相ζ包６ｎｅｔｉ−（％］ 第２図 早呵難）時代（−） 第４図 第５図 飽）り’ｉ　（ｍｍ） 第６図 ７に値（匁FIG. 1 is a graph showing the influence of the addition of fine ore A on the air permeability of the raw material layer. FIG. 2 is a graph showing the influence of the average particle diameter ratio of fine ore and sintering raw material on the air permeability of the raw material layer. FIG. 3 is a graph showing the relative permeability of various ores to be added. FIG. 4 is a schematic diagram of a pseudo particle. FIG. 5 is a graph showing changes in particle size distribution due to granulation. FIG. 6 is a graph showing the air permeability of ores A, B, and C under the condition that no fine ore is added. Fig. 1 Phase ζ envelope 6neti- (%) Fig. 2 Era (-) Fig. 4 Fig. 5 Saturation) i (mm) Fig. 6 Value (momme)

Claims (1)

【特許請求の範囲】[Claims] 粉鉱石を主成分とする焼結原料に、該焼結原料との平均
粒径比が０．０４以下である微粉鉱石を擬似粒子化剤と
して、混合した後、造粒を行うことを特徴とする焼結原
料の事前処理方法。A sintering raw material mainly composed of fine ore is mixed with fine ore having an average particle size ratio of 0.04 or less to the sintering raw material as a pseudo-granulating agent, and then granulation is performed. A pre-treatment method for sintering raw materials.