JPH046764B2 - - Google Patents
Info
- Publication number
- JPH046764B2 JPH046764B2 JP27506386A JP27506386A JPH046764B2 JP H046764 B2 JPH046764 B2 JP H046764B2 JP 27506386 A JP27506386 A JP 27506386A JP 27506386 A JP27506386 A JP 27506386A JP H046764 B2 JPH046764 B2 JP H046764B2
- Authority
- JP
- Japan
- Prior art keywords
- tuyere
- furnace
- tuyeres
- ore
- reduction furnace
- 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
- 238000002844 melting Methods 0.000 claims description 17
- 230000008018 melting Effects 0.000 claims description 17
- 239000003575 carbonaceous material Substances 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 16
- 238000003723 Smelting Methods 0.000 claims description 11
- 239000002245 particle Substances 0.000 claims description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 4
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 4
- 239000003638 chemical reducing agent Substances 0.000 claims description 2
- 238000011017 operating method Methods 0.000 claims 1
- 238000006722 reduction reaction Methods 0.000 description 23
- 238000004519 manufacturing process Methods 0.000 description 9
- 239000002893 slag Substances 0.000 description 9
- 239000000571 coke Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 229910052751 metal Inorganic materials 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910044991 metal oxide Inorganic materials 0.000 description 4
- 150000004706 metal oxides Chemical class 0.000 description 4
- 238000007664 blowing Methods 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 210000001015 abdomen Anatomy 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000011818 carbonaceous material particle Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000012255 powdered metal Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Manufacture Of Iron (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、竪型溶融還元炉の操業方法に関し、
金属酸化物を含有する粉状鉱石を溶融還元して溶
融金属を製造する炉の操業方法に関する。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method of operating a vertical smelting reduction furnace,
The present invention relates to a method for operating a furnace for producing molten metal by melting and reducing powdery ore containing metal oxides.
地下資源としての鉄鉱石などの金属酸化物の形
態としては、塊状のものより粉状のものが大半で
あり、将来さらに粉状鉱石が増大すると予想され
る。このような鉱石を粉状のままで直接使用する
ことが省エネルギー、製造コストなどの面で有利
となる。
Most metal oxides such as iron ore as underground resources are in the form of powder rather than lumps, and it is expected that the number of powder ores will increase further in the future. Direct use of such ores in powder form is advantageous in terms of energy savings and manufacturing costs.
従来、粉鉱石の溶融還元法として予備還元鉱を
電気炉、転炉などの溶解炉で溶融還元する方法が
とられていた。その場合、予備還元鉱にバインダ
ーを添加して塊成化し、その塊成物を溶解炉で溶
融還元する方式が多い。しかし、このような方式
では塊成化のための設備、処理鉱費、処理エネル
ギーなどを必要とするばかりでなく、塊成化した
のち焼成する場合には、その際に焼成炉から排出
されるガスのNOx、SOxならびにダストを処理
するための費用が多大である。 Conventionally, as a method for melting and reducing fine ore, a method has been used in which preliminary reduced ore is melted and reduced in a melting furnace such as an electric furnace or a converter. In that case, there are many methods in which a binder is added to the pre-reduced ore to agglomerate it, and the agglomerate is melted and reduced in a melting furnace. However, this type of method not only requires equipment for agglomeration, processing costs, processing energy, etc., but also, when agglomerated and then fired, waste is discharged from the kiln. The cost of treating gas NOx, SOx, and dust is significant.
そこで特公昭59−18452にて粉鉱石を溶融還元
する方法として竪型炉タイプの溶融還元炉を提案
した。 Therefore, we proposed a vertical furnace type smelting reduction furnace as a method for smelting and reducing fine ore in the Japanese Patent Publication No. 59-18452.
それによると、炉下部に設置された高温空気を
吹込む上下２段の羽口のうち、少なくとも上段の
羽口から粉状鉱石を高温空気とともに竪型炉内に
吹込み、炉内に充填した炭材を燃焼させて溶融還
元することを特徴としている。上段および下段羽
口を有する竪型溶融還元炉では上下段羽口間に充
填層を形成している炭材が燃焼して高温が発生す
る。従つて、上段羽口から吹込まれる粉鉱石は加
熱されて溶融し、充填層を滴下する間に固体炭材
により直接還元されて溶融状態のメタルおよびス
ラグを生成し、炉底部に溜まる。 According to the report, powdered ore was blown into the vertical furnace along with high-temperature air from at least the upper tuyere of the upper and lower tuyeres installed at the bottom of the furnace to blow in high-temperature air, and the furnace was filled. It is characterized by burning carbonaceous materials and melting and reducing them. In a vertical melting reduction furnace having upper and lower tuyeres, the carbonaceous material forming a packed layer between the upper and lower tuyeres burns and generates high temperatures. Therefore, the fine ore injected from the upper tuyere is heated and melted, and while dropping through the packed bed, it is directly reduced by the solid carbonaceous material to produce molten metal and slag, which accumulate at the bottom of the furnace.
上記の方法では、上段羽口から供給される粉鉱
石が羽口先で速やかに溶融しないと、炉の下部領
域に滴下することができず、操業トラブルの原因
となるので、下段羽口からも高温空気や酸素富化
空気を吹込むことによつてトラブルを防止してい
る。 In the above method, if the fine ore supplied from the upper tuyere does not melt quickly at the tip of the tuyere, it will not be able to drip into the lower area of the furnace, causing operational troubles. Problems are prevented by blowing air or oxygen-enriched air.
上段および下段羽口を有する竪型溶融還元炉で
の生産量は、レースウエイ有効界面積から定まる
鉱石の還元反応速度、ならびに風量により定まる
レースウエイの大きさなどに影響される。とりわ
け、レースウエイ有効界面積から定まる反応速度
はメタルの生産量を決める重要因子であり、それ
は炭材粒径や上下段羽口間の距離で決まるが、炭
材の棚つり、吹抜けまたは上下段羽口間での溶融
金属やスラグのフラツデイング（気液向流の充填
層で流下していた液体が上昇ガスに吹上げられて
流下しなくなる現象）を考慮したガス流速と、炭
材粒径および操業条件に見合う上下段羽口間の距
離については十分な検討はなされていない。 The production volume in a vertical smelting reduction furnace having upper and lower tuyeres is influenced by the ore reduction reaction rate determined by the effective interfacial area of the raceway, and the size of the raceway determined by the air volume. In particular, the reaction rate determined by the effective interfacial area of the raceway is an important factor that determines the production amount of metal.It is determined by the carbon material particle size and the distance between the upper and lower tuyeres, but it is The gas flow rate takes into account the flattening of molten metal and slag between the tuyeres (a phenomenon in which the liquid that was flowing down in the packed bed of gas-liquid counterflow is blown up by the rising gas and stops flowing down), and the carbon material particle size and Sufficient consideration has not been given to the distance between the upper and lower tuyeres that suits the operating conditions.
粉鉱石を上段および下段羽口のうちの上段羽口
より吹込む竪型炉の溶融還元方法では、上下段羽
口先でのレースウエイ有効界面積により還元反応
速度が定まり、生産性に影響する。それらは、炉
床径、炭材粒径や上下段羽口間の距離で決定され
る。また、炭材を炉内に充填して熱風を炉内へ送
風する場合、炭材粒径によつてはある送風量で吹
抜け、あるいはスラグフラツデイングが生じ操業
トラブルの原因となる。
In the smelting reduction method using a vertical furnace in which fine ore is injected through the upper tuyere of the upper and lower tuyeres, the reduction reaction rate is determined by the effective interfacial area of the raceway at the tips of the upper and lower tuyeres, which affects productivity. They are determined by the hearth diameter, the carbon material particle size, and the distance between the upper and lower tuyeres. Furthermore, when a furnace is filled with carbonaceous material and hot air is blown into the furnace, depending on the particle size of the carbonaceous material, blow-through or slag flooding may occur at a certain amount of air flow, causing operational troubles.
そこで生産量に見合う炭材粒径に応じて上段と
下段羽口の距離を定めることにより定められた生
産量を確保して操業の安定化を図ることができる
ことがわかつた。 Therefore, it was found that by determining the distance between the upper and lower tuyeres according to the carbon material particle size that corresponds to the production volume, it was possible to secure the specified production volume and stabilize the operation.
本発明は上下段羽口を有し、上段羽口より粉状
鉱石等を吹込む竪型炉の溶融還元方法に関し、操
業上の制約条件に見合う炉床径、コークス粒径、
上下段羽口間の距離を適正に定め、操業の安定を
図ろうとするものである。 The present invention relates to a method for melting and reducing a vertical furnace having upper and lower tuyeres and injecting powdered ore, etc. from the upper tuyere, and is concerned with a hearth diameter, coke particle diameter, etc. that meet operational constraints.
The aim is to appropriately determine the distance between the upper and lower tuyeres to stabilize operations.
本発明は、炭素系固体還元剤の充填層が形成さ
れたシヤフト炉であつてその下段羽口より高温空
気を吹込み、上段羽口より粉状鉱石を吹込む複数
の羽口を有する溶融還元炉操業方法において、炭
材の平均粒径DC（ｍ）ならびに炉床径DT（ｍ）と、
上段および下段の羽口間隔Ｈ（ｍ）との間に下記
式を満たすことを特徴とする竪型溶融還元炉の操
業方法である。
The present invention is a shaft furnace in which a packed bed of a carbon-based solid reducing agent is formed, and has a plurality of tuyeres into which high-temperature air is blown from the lower tuyere and powdered ore is blown from the upper tuyere. In the furnace operation method, the average particle diameter of the carbonaceous material D C (m) and the hearth diameter D T (m),
This is a method of operating a vertical melting reduction furnace, characterized in that the following formula is satisfied between the upper and lower tuyere intervals H (m).
Ｈ＝ｋ・DC・DT 0.3 但し、30＜ｋ＜100である。 H=k・D C・D T 0.3 However, 30<k<100.
上段および下段羽口を有する竪型の溶融還元炉
であつて、粉鉱石などの金属酸化物を少なくとも
上段の羽口から吹込む竪型溶融還元炉は、上下段
羽口間に充填層を形成する炭材が800〜1000℃に
加熱された空気により燃焼して高温が発生する。
上段羽口から吹込まれる粉鉱石は加熱され、溶融
し、充填層を滴下する間に、固体炭材により直接
還元されて溶融状態のメタルおよびスラグが生成
する。
A vertical smelting reduction furnace having upper and lower tuyeres, in which metal oxides such as fine ore are injected from at least the upper tuyere, forms a packed layer between the upper and lower tuyeres. The carbonaceous material is combusted by air heated to 800-1000℃, generating high temperatures.
The fine ore injected from the upper tuyere is heated and melted, and while dropping through the packed bed, it is directly reduced by solid carbonaceous material to produce molten metal and slag.
その場合、上段羽口から供給される粉鉱石が羽
口先で速やかに溶融するように、下段羽口からも
高温空気や酸素富化空気を吹込んで溶融還元を促
進している。上記の竪型溶融還元炉の生産性は風
量から定まるレースウエイの大きさ、上段および
下段羽口のレースウエイ有効界面積から定まる還
元反応速度が影響する。 In this case, hot air or oxygen-enriched air is also blown from the lower tuyere to promote melting and reduction so that the fine ore supplied from the upper tuyere quickly melts at the tip of the tuyere. The productivity of the above-mentioned vertical melting reduction furnace is influenced by the size of the raceway determined by the air flow rate and the reduction reaction rate determined by the raceway effective interfacial area of the upper and lower tuyeres.
そしてレースウエイ有効界面積は、ある生産量
を確保するに必要な送風量から定まるレースウエ
イの大きさが一定の場合、炭材粒径から求まる充
填層容積当りのコークス表面積や上下段羽口間の
距離で決まる。ところで炉内では、炉口ガス流速
や羽口間のガス流速によつて、流速が小の時、炭
材の棚つり、大きい時吹抜けおよび羽口間のガス
流速が大きいと、スラグのフラツデイングが生
じ、操業トラブルの原因となる。そのため、炭材
粒径は吹抜けやスラグフラツデイングを考慮し、
炉口流速炉、腹流速などから決まる吹抜け流速、
フラツデイング流速ならびに定められた生産量を
確保するに必要な炉床径や上下段羽口の距離から
総合的に決定されるべきである。 The effective interfacial area of the raceway is determined by the amount of air flow required to ensure a certain production volume.If the size of the raceway is constant, the surface area of the coke per packed bed volume determined from the particle size of the carbonaceous material, and the gap between the upper and lower tuyeres. determined by the distance. By the way, in the furnace, depending on the gas flow rate at the furnace mouth and the gas flow rate between the tuyeres, when the flow rate is low, the carbon material is suspended, when the flow rate is high, it blows through, and when the gas flow rate between the tuyeres is high, the slag is flattened. This can cause operational problems. Therefore, the carbonaceous material particle size should be determined by taking into account blow-through and slag flattening.
The blow-through flow velocity is determined by the furnace mouth velocity furnace, belly flow velocity, etc.
It should be determined comprehensively from the hearth diameter and the distance between the upper and lower tuyeres necessary to ensure the flattening flow rate and the specified production volume.
第１図に炉床径に対する適正な２段羽口間隔Ｈ
とコークスDCの比の関係を示す。本発明によれ
ば、２段羽口間隔Ｈとコークル粒径DCの比を炉
床径DTに対して
30DT 0.3＜Ｈ／DC＜100DT 0.3
の範囲内に定めれば吹抜けフラツデイングが発生
せずに操業が安定することがわかつた。逆に炭材
粒度を予め定めた場合には、２段羽口間隔Ｈは
30DC×DT 0.3＜Ｈ＜100DC×DT 0.3
の範囲とすれば最適となる。 Figure 1 shows the appropriate two-stage tuyere spacing H for the hearth diameter.
The relationship between the ratio of C and coke D C is shown. According to the present invention, if the ratio of the two-stage tuyere interval H to the corkle particle diameter D C is set within the range of 30D T 0.3 < H/D C < 100D T 0.3 with respect to the hearth diameter D T , the blow-through flattening can be achieved. It was found that the operation was stable without any occurrence of this problem. On the contrary, when the carbon material particle size is determined in advance, the two-stage tuyere interval H is optimal if it is in the range of 30D C ×D T 0.3 <H<100D C ×D T 0.3 .
しかしながら、第１図の適正範囲より上の領域
ではフラツデイングや棚つりが起こり易く、下の
領域では吹抜けや還元不足が起こり易く、正常か
つ安定な操業ができない。DTが定まれば、ある
生産量を確保するに必要な送風量は一義的に決定
される。 However, in the region above the appropriate range shown in FIG. 1, flattening and shelf suspension are likely to occur, and in the region below, blow-through and insufficient reduction are likely to occur, making normal and stable operation impossible. Once D T is determined, the amount of air flow required to secure a certain production amount is uniquely determined.
第２図に溶融還元炉のプロセスフローを基に実
施例を示す。
FIG. 2 shows an example based on the process flow of a melting reduction furnace.
粉状の金属酸化物と溶剤は所定の混合割合でホ
ツパ１に入つており、鉱石供給量調節フイーダ３
で適量切り出され、吹込用パイプ４を経て、上段
の羽口６より溶融還元炉５内に吹込まれる。コー
クスはコークス用ホツパ２に貯蔵され適量溶融還
元炉５内に装入される。 Powdered metal oxide and solvent are put into the hopper 1 at a predetermined mixing ratio, and the ore supply amount adjustment feeder 3
An appropriate amount is cut out, passed through the blowing pipe 4, and blown into the melting reduction furnace 5 through the upper tuyere 6. Coke is stored in a coke hopper 2 and charged in an appropriate amount into a smelting reduction furnace 5.
次に送風空気は送風ブロワ７より熱交換器９に
送られる過程で適量な酸素が酸素流量調節器８を
介して添加され、熱交換器９に送られ1000〜1100
℃に加熱され、送風管１０を通して熱風として上
段羽口６および下段羽口１１からそれぞれ溶融還
元炉５内に送風される。そして溶融還元炉５内に
おいて酸化物は送風空気中の酸素とコークス中の
カーボンが反応する際に発生する燃焼熱と還元ガ
スならびに酸化物とカーボンの接触により溶融還
元されて流下し、溶融メタルは出銑口１２、スラ
グは出滓口１３より排出される。 Next, in the process of sending the blast air from the blower 7 to the heat exchanger 9, an appropriate amount of oxygen is added via the oxygen flow rate regulator 8, and the air is sent to the heat exchanger 9 at a rate of 1000 to 1100.
℃, and is blown as hot air through the blast pipe 10 into the melting reduction furnace 5 from the upper tuyere 6 and the lower tuyere 11, respectively. Then, in the melting reduction furnace 5, the oxide is melted and reduced by the combustion heat and reducing gas generated when the oxygen in the blast air reacts with the carbon in the coke, as well as the contact between the oxide and the carbon, and the molten metal flows down. The tap hole 12 and the slag are discharged from the slag hole 13.
実施例としては炉内径1.2ｍの溶融還元炉に上
下段羽口各３本を取り付け、上下段羽口間隔1.0
ｍとした溶融還元炉を用いてコークス粒径15mm、
送風量1600Nm3／hr、送風温度900℃、鉱石吹込
量600〜800Kg／hrの範囲で試験操業を行い、銑鉄
12トン／日の生産量が確保できた。 As an example, three upper and lower tuyeres are installed in a melting reduction furnace with an inner diameter of 1.2 m, and the interval between the upper and lower tuyeres is 1.0.
Using a melting reduction furnace with a diameter of 15 mm,
Test operations were conducted with an air flow rate of 1600Nm 3 /hr, a blowing temperature of 900℃, and an ore injection amount of 600 to 800Kg/hr.
A production capacity of 12 tons/day was secured.
本発明によれば、竪型溶融還元炉においてコー
クスの吹抜け等のトラブルもなく従来より安定し
た操業が行えるようになつた。
According to the present invention, a vertical smelting reduction furnace can now operate more stably than before without problems such as coke blow-through.
第１図は適正な２段羽口間隔範囲を示すグラ
フ、第２図は本発明を示す溶融還元炉プロセスフ
ローシートである。
１……鉱石用ホツパ、２……コークス用ホツ
パ、３……鉱石供給量調節フイーダ、４……鉱石
吹込用パイプ、５……溶融還元炉、６……上段羽
口、７……送風ブロワ、８……酸素流量調節器、
９……熱交換器、１０……送風管、１１……下段
羽口、１２……出銑口、１３……出滓口。
FIG. 1 is a graph showing an appropriate two-stage tuyere spacing range, and FIG. 2 is a smelting reduction furnace process flow sheet showing the present invention. 1... hopper for ore, 2... hopper for coke, 3... ore supply amount adjustment feeder, 4... ore injection pipe, 5... smelting reduction furnace, 6... upper tuyere, 7... blast blower , 8...Oxygen flow rate regulator,
9...Heat exchanger, 10...Blow pipe, 11...Lower tuyere, 12...Tapping port, 13...Slag port.
Claims (1)
フト炉であつてその下段羽口より高温空気を吹込
み、上段羽口より粉状鉱石を吹込む複数の羽口を
有する溶融還元炉の操業方法において、炭材の平
均粒径DC（ｍ）ならびに炉床径DT（ｍ）と上段と
下段の羽口間隔Ｈ（ｍ）との間に下記式を満たす
ことを特徴とする竪型溶融還元炉の操業方法。 記 Ｈ＝ｋ・DC・DT 0.3 但し、30＜ｋ＜100である。[Scope of Claims] 1. A shaft furnace in which a packed bed of a carbon-based solid reducing agent is formed, and has a plurality of tuyeres into which high-temperature air is blown from the lower tuyere and powdered ore is blown from the upper tuyere. In the operating method of the smelting reduction furnace, the following formula must be satisfied between the average particle diameter of the carbonaceous material D C (m), the hearth diameter D T (m), and the tuyere spacing H (m) between the upper and lower stages. A method of operating a vertical melting reduction furnace characterized by: Note H=k・D C・D T 0.3 However, 30<k<100.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27506386A JPS63128108A (en) | 1986-11-18 | 1986-11-18 | Operation method for vertical type smelting reduction furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27506386A JPS63128108A (en) | 1986-11-18 | 1986-11-18 | Operation method for vertical type smelting reduction furnace |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63128108A JPS63128108A (en) | 1988-05-31 |
| JPH046764B2 true JPH046764B2 (en) | 1992-02-06 |
Family
ID=17550322
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27506386A Granted JPS63128108A (en) | 1986-11-18 | 1986-11-18 | Operation method for vertical type smelting reduction furnace |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63128108A (en) |
-
1986
- 1986-11-18 JP JP27506386A patent/JPS63128108A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63128108A (en) | 1988-05-31 |
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