JPH03291314A - Method for operating blast furnace - Google Patents
Method for operating blast furnaceInfo
- Publication number
- JPH03291314A JPH03291314A JP9299290A JP9299290A JPH03291314A JP H03291314 A JPH03291314 A JP H03291314A JP 9299290 A JP9299290 A JP 9299290A JP 9299290 A JP9299290 A JP 9299290A JP H03291314 A JPH03291314 A JP H03291314A
- Authority
- JP
- Japan
- Prior art keywords
- furnace
- iron
- blast furnace
- iron ore
- amount
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title abstract description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 75
- 229910052742 iron Inorganic materials 0.000 claims abstract description 36
- 239000000571 coke Substances 0.000 claims abstract description 12
- 239000012256 powdered iron Substances 0.000 claims description 15
- 238000011017 operating method Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 14
- 150000002505 iron Chemical class 0.000 abstract 2
- 239000002801 charged material Substances 0.000 abstract 1
- 239000000463 material Substances 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 239000003245 coal Substances 0.000 description 14
- 229910052710 silicon Inorganic materials 0.000 description 14
- 239000010703 silicon Substances 0.000 description 14
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 13
- 239000002184 metal Substances 0.000 description 13
- 229910052751 metal Inorganic materials 0.000 description 13
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 10
- 230000007423 decrease Effects 0.000 description 8
- 238000002347 injection Methods 0.000 description 8
- 239000007924 injection Substances 0.000 description 8
- 239000000843 powder Substances 0.000 description 8
- 238000006722 reduction reaction Methods 0.000 description 7
- 230000015572 biosynthetic process Effects 0.000 description 6
- 240000001549 Ipomoea eriocarpa Species 0.000 description 4
- 235000005146 Ipomoea eriocarpa Nutrition 0.000 description 4
- 238000009423 ventilation Methods 0.000 description 4
- 210000001015 abdomen Anatomy 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000001934 delay Effects 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 2
- 239000011449 brick Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910052814 silicon oxide Inorganic materials 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000007664 blowing Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 208000024891 symptom Diseases 0.000 description 1
Landscapes
- Manufacture Of Iron (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は、炉頂から装入さける鉄鉱石と羽目から吹込ま
れる粉状鉄源の合計の量を高炉の炉熱が安定するように
調整することにより、生産性を安定させる高炉操業法に
関する。Detailed Description of the Invention (Industrial Application Field) The present invention aims to reduce the total amount of iron ore charged from the top of the furnace and powdered iron source injected from the siding so that the furnace heat of the blast furnace is stabilized. This article relates to a blast furnace operating method that stabilizes productivity through adjustment.
(従来の技術)
最近の高炉操業にあっては、後工程である製鋼工程にお
ける品質の向上、経済性の観点から低シリコン操業が指
向されている。この種の操業形態の代表的なものとして
、微粉炭とともに酸化鉄粉または還元鉄粉などの粉状鉄
源を羽口部から吹込む方法があり、特開昭57−137
402号公報に開示されている。(Prior Art) In recent blast furnace operations, low-silicon operations are being pursued from the viewpoint of improving quality in the subsequent steel manufacturing process and from the viewpoint of economic efficiency. A typical method of this type of operation is to inject a powdered iron source such as oxidized iron powder or reduced iron powder together with pulverized coal from the tuyere.
It is disclosed in Publication No. 402.
このようにして吹込まれた酸化鉄粉、還元鉄粉などの粉
状鉄源は高炉内で還元反応を受けて金属状態に還元され
るとともに、還元途中で高炉内の溶銑と反応して2(F
eO)十旦」=2乙二十(SiOy)の反応により溶銑
中のノリコンを低下させる。Powdered iron sources such as iron oxide powder and reduced iron powder that are injected in this way undergo a reduction reaction in the blast furnace and are reduced to a metallic state. F
The reaction of SiOy (SiOy) lowers the silicon in the hot metal.
高炉操業安定時には、羽口部から吹込まれる粉状鉄源の
分だけ高炉の炉頂から装入する鉄鉱石の量を減らすこと
が出来る。When blast furnace operation is stable, the amount of iron ore charged from the top of the blast furnace can be reduced by the amount of powdered iron source injected from the tuyere.
通常、炉頂から装入される鉄鉱石は、炉内の通気性を維
持するために、塊成化されたものが使用されているから
、予備処理の必要な鉄鉱石に代えて単価の低い粉状鉄源
を使用することは、高炉操業の経済性を高める上でも効
果が大きい。Normally, the iron ore that is charged from the top of the furnace is agglomerated in order to maintain ventilation inside the furnace, so it is a cheaper alternative to iron ore that requires preliminary treatment. Using a powdered iron source is also highly effective in improving the economic efficiency of blast furnace operation.
(発明が解決しようとする課題)
ところで従来の高炉操業において、高炉の炉熱低下以外
の理由で炉頂から装入する鉄鉱石の量を減らす場合が存
在する。それは高炉のシャフト下部から炉腹部、朝顔部
にかけて炉壁部の装入物の降下遅延、停滞、付着物の生
成などにより通気性の不良、装入物の降下異常が発生し
た場合、または発生の徴候がみられる場合であり、この
とき炉壁部の鉱石とコークスの比率(以下0/Cと略す
)を減らし、その分生間部から中心部のO/Cを増加す
る。中間部から中心部のO/Cを増加できない場合は、
炉壁部の0/Cを減らすとともに全体のO/Cを減らす
。これにより炉壁部のガス流を強化して装入物の降下遅
延、停滞、付着物の生成を解消、または防止する。(Problems to be Solved by the Invention) In conventional blast furnace operations, there are cases in which the amount of iron ore charged from the top of the blast furnace is reduced for reasons other than a decrease in the furnace heat of the blast furnace. This occurs when there is poor ventilation or abnormality in the descent of the burden due to delays in the descent of the burden, stagnation, or the formation of deposits on the furnace wall from the bottom of the shaft of the blast furnace to the belly of the furnace and the morning glory. If symptoms are observed, the ratio of ore to coke (hereinafter abbreviated as 0/C) in the furnace wall is reduced, and the O/C in the central part is increased. If it is not possible to increase the O/C from the middle to the center,
Reduce the O/C of the furnace wall and reduce the overall O/C. This strengthens the gas flow at the furnace wall and eliminates or prevents delays in lowering the charge, stagnation, and the formation of deposits.
炉壁部の装入物の降下遅延、停滞、付着物の生成が起こ
るときは高炉の炉熱低下を伴わないことが多く、全体の
O/Cを減らすことはコークス比の上昇となり、生産量
の減少、溶銑中のシリコンの増加を招き高炉操業上好ま
しくない。装入物の降下遅延、停滞、付着物の生成を解
消または防止するには3日ないし10日かかることが多
く、この間生産量の減少、溶銑中のシリコンの増加が続
くことになる。羽口部から粉状鉄源を吹込んでいる場合
でも通気性が不良になることを恐れて、粉状鉄源の量を
変えないかカットしてしまうことが多い。When a delay in the descent of the charge, stagnation, or the formation of deposits on the furnace wall occurs, it is often not accompanied by a decrease in the furnace heat of the blast furnace.Reducing the overall O/C will increase the coke ratio and reduce the production volume. This is unfavorable for blast furnace operation as it causes a decrease in silicon content and an increase in silicon content in the hot metal. It often takes 3 to 10 days to eliminate or prevent the delay in lowering the charge, stagnation, and the formation of deposits, during which time production continues to decrease and silicon levels in the hot metal continue to increase. Even when powdered iron source is injected through the tuyeres, the amount of powdered iron source is often left unchanged or cut for fear of poor ventilation.
このように従来の高炉操業は3日ないし10日の生産量
の減少、溶銑中のシリコンの増加を余儀なくされてきた
。As described above, conventional blast furnace operations have been forced to reduce production by 3 to 10 days and increase the amount of silicon in the hot metal.
そこで本発明は高炉の炉熱低下を伴わない装入物の降下
遅延、停滞、付着物の生成が起こったときに、それを解
消または防止するためにコークス比の上昇を行わないで
、一定の生産量、一定の溶銑中のシリコンを維持するこ
とを目的とする。Therefore, the present invention aims to eliminate or prevent the slow descent of the charge, stagnation, and the formation of deposits without decreasing the furnace heat of the blast furnace, without increasing the coke ratio. The aim is to maintain the production volume and silicon in the hot metal constant.
(課題を解決するための手段および作用)本発明の高炉
操業法は、その目的を達成するために、羽口部から粉状
鉄源を高炉の内部に吹込み、炉頂から鉄鉱石とコークス
を交互に装入する操業法において、炉頂から装入する鉄
鉱石を減らす操作を行ったとき、該鉄鉱石が羽口部に到
達した後に、該鉄鉱石に相当する量の粉状鉄源を、羽口
部から高炉の内部に吹込むことを特徴とする。(Means and effects for solving the problem) In order to achieve the object, the blast furnace operating method of the present invention injects a powdered iron source into the blast furnace from the tuyere part, and iron ore and coke from the top of the furnace. In an operation method in which iron ore is alternately charged, when an operation is performed to reduce the amount of iron ore charged from the top of the furnace, after the iron ore reaches the tuyere, an amount of powdered iron source corresponding to the iron ore is is blown into the inside of the blast furnace from the tuyere.
高炉のシャフト下部から炉腹部、朝顔部にかけて炉壁部
の装入物の降下遅延、停滞、付着物の生成などにより通
気性不良、装入物の降下異常が発生した場合、または発
生の徴候がみられる場合は、高炉の炉熱低下を伴わない
ことが多い(すなわちレースウェイ部は安定した反応伝
熱状態にある)から、羽口部における送風条件を変える
必要がない。If poor ventilation or an abnormality in the descent of the burden occurs due to delays in the descent of the burden, stagnation, or the formation of deposits on the furnace wall from the bottom of the shaft of the blast furnace to the belly of the furnace and the morning glory, or if there are any signs of such occurrence. If this occurs, it is often not accompanied by a decrease in the furnace heat of the blast furnace (that is, the raceway section is in a stable reaction heat transfer state), so there is no need to change the air blowing conditions at the tuyere section.
しかし炉頂から装入する鉄鉱石の量を減らしくすなわち
全体のO/Cを減らし)、5〜6時間後に羽口部に降下
したO/Cの装入物が到達したときは、レースウェイ部
は炉熱過剰となる。本発明において、炉頂から装入する
鉄鉱石が羽口部に到達した後とは、炉頂からの装入後5
〜6時間経過したときをいう。このときに炉頂から装入
する鉄鉱石の量を減らした分に相当する量の粉状鉄源を
羽口部から吹込むことにより、レースウェイ部は安定し
た反応伝熱状態に維持される。これにより通気性が不良
に至ることはない。However, by reducing the amount of iron ore charged from the top of the furnace (that is, reducing the overall O/C), when the O/C charge that descended to the tuyere reached the raceway after 5 to 6 hours, part of the furnace becomes overheated. In the present invention, after the iron ore charged from the top of the furnace reaches the tuyere section, 5 hours after the iron ore is charged from the top of the furnace.
~6 hours have passed. At this time, the raceway section is maintained in a stable reaction heat transfer state by injecting from the tuyeres an amount of powdered iron source equivalent to the reduced amount of iron ore charged from the top of the furnace. . This does not lead to poor air permeability.
炉頂から装入する鉄鉱石の量を減らした分に相当する量
の粉状鉄源は鉄分が一定となることを原則とするが、酸
化鉄粉か還元鉄粉かによって、その還元部の分だけ量を
加減する。粉状鉄源と同時に微粉炭を吹込んでいる場合
は、微粉炭の量を増加することにより粉状鉄源の量を増
加できる。粉状鉄源の還元率と相当する量の関係、微粉
炭の増用量の関係を第1表に示す。In principle, the amount of powdered iron source equivalent to the reduced amount of iron ore charged from the top of the furnace will have a constant iron content, but depending on whether it is oxidized iron powder or reduced iron powder, the reduction part Adjust the amount accordingly. When pulverized coal is injected at the same time as the pulverized iron source, the amount of pulverized iron source can be increased by increasing the amount of pulverized coal. Table 1 shows the relationship between the reduction rate of the powdered iron source and the corresponding amount, and the relationship between the increased amount of pulverized coal.
第 1 表 (実施例) 以下実施例により本発明の特徴を具体的に説明する。Part 1 table (Example) The features of the present invention will be specifically explained below with reference to Examples.
第2表に示すように、実施例1はオールコークス操業に
おいて、シャフト下部の炉壁部レンガに設置した温度計
の円周方向の平均値が通常の120℃±20℃から外れ
て、95℃となったため、炉頂から装入している鉱石量
75t/回をIt/回減らし、5時間後に羽口から吹込
む粒度1.Oam以下の酸化鉄粉(還元率0%)の量4
080 Kg/hr増加させた場合であり、オールコー
クス操業の基準操業1に対して、生産量、溶銑中のシリ
コンはほぼ一定である。As shown in Table 2, in the all-coke operation in Example 1, the average value in the circumferential direction of the thermometer installed on the furnace wall brick at the bottom of the shaft deviated from the normal value of 120°C ± 20°C to 95°C. Therefore, the amount of ore charged from the top of the furnace was reduced from 75 tons/time to It/time, and after 5 hours, the particle size of the ore injected from the tuyere was 1. Amount of iron oxide powder (reduction rate 0%) below Oam 4
080 Kg/hr, and the production amount and silicon in the hot metal are almost constant compared to the standard operation 1, which is an all-coke operation.
比較例1はオールコークス操業において、シャフト下部
の炉壁部レンガに設置した温度計の円周方向の平均値が
通常の120℃±20℃から外れて、95℃となったた
め、炉頂から装入している鉱石量75t/回をIt/回
減らし、そのまま操業を継続した場合であり、オールコ
ークス操業の基準操業1に対して、生産量低下、溶銑中
のシリコンの上昇が大きい。In Comparative Example 1, during all-coke operation, the average value in the circumferential direction of the thermometer installed on the furnace wall brick at the bottom of the shaft deviated from the normal 120°C ± 20°C and reached 95°C. This is a case where the amount of ore inputted is reduced by 75t/time to It/time and the operation is continued as it is, and the production volume decreases and the silicon content in the hot metal increases significantly compared to the standard operation 1 of all coke operation.
第3表に示すように、実施例2は微粉炭吹込み操業にお
いて、炉腹部のステーブに埋め込んだ温度計の円周方向
の平均値が通常の100℃±15℃から外れて、80℃
となったため、炉頂から装入している鉱石量90t/回
を1.5t/回減らし、6時間後に羽目から吹込む粒度
0.51以下の酸化鉄粉(還元率30%)の量を815
0 Kg/hr増加させ、かつ微粉炭の量をI 000
Kg/hr増加させた場合であり、微粉炭吹込み操業
の基準操業2に対して、生産量、溶銑中のシリコンはほ
ぼ一定である。As shown in Table 3, in Example 2, during the pulverized coal injection operation, the average value in the circumferential direction of the thermometer embedded in the stave in the furnace belly deviated from the normal 100°C ± 15°C to 80°C.
Therefore, the amount of ore charged from the top of the furnace (90t/time) was reduced by 1.5t/time, and the amount of iron oxide powder with a particle size of 0.51 or less (30% reduction rate) injected from the siding after 6 hours was reduced. 815
0 Kg/hr, and the amount of pulverized coal was increased to I 000
Kg/hr is increased, and the production amount and silicon in the hot metal are almost constant compared to the standard operation 2 of the pulverized coal injection operation.
実施例3は微粉炭吹込み操業において、朝顔部のステー
ブに埋め込んだ温度計の円周方向の平均値が通常の15
0℃±25℃から外れて、120℃となったため、炉頂
から装入している鉱石量90t/回を1.5t/回減ら
し、6時間後に羽口から吹込む粒度0.75am以下の
酸化鉄粉(還元率60%)の量を9270 Kg/hr
増加させ、かつ微粉炭の量を500 Kg/hr増加さ
せた場合であり、微粉炭吹込み操業の基準操業2に対し
て、生産量、溶銑中のシリコンはほぼ一定である。In Example 3, during the pulverized coal injection operation, the average value in the circumferential direction of the thermometer embedded in the stave of the morning glory section was 15
As the temperature exceeded 0℃±25℃ and reached 120℃, the amount of ore charged from the top of the furnace (90t/time) was reduced by 1.5t/time, and after 6 hours, the amount of ore charged from the tuyere with a grain size of 0.75am or less was reduced. The amount of iron oxide powder (reduction rate 60%) was 9270 Kg/hr.
This is a case where the amount of pulverized coal is increased by 500 kg/hr, and the production amount and silicon in the hot metal are almost constant compared to the standard operation 2 of the pulverized coal injection operation.
実施例4は微粉炭吹込み操業において、朝顔部のステー
ブに埋め込んだ温度計の円周方向の平均値が通常の15
0℃±25℃から外れて、120℃となったため、炉頂
から装入している鉱石量90t/回を1.5t/回減ら
し、6時間後に羽口から吹込む粒度0.25g+g+以
下の酸化鉄粉(還元率100%)の量を186301[
g/hr増加させた場合であり、微粉炭吹込み操業の基
準操業2に対して、生産量は上昇し、溶銑中のシリコン
は低下している。In Example 4, during the pulverized coal injection operation, the average value in the circumferential direction of the thermometer embedded in the stave of the morning glory section was 15
Since the temperature was deviated from 0℃±25℃ and became 120℃, the amount of ore charged from the top of the furnace, 90t/time, was reduced by 1.5t/time, and after 6 hours, the amount of ore charged from the tuyere was reduced to 0.25g+g+ or less. The amount of iron oxide powder (reduction rate 100%) was 186301[
g/hr is increased, and the production amount increases and the silicon content in the hot metal decreases compared to the standard operation 2 of the pulverized coal injection operation.
比較例2は微粉炭吹込み操業において、炉腹部ステーブ
に埋め込んだ温度計の円周方向の平均値が通常の100
℃±15℃から外れて、80℃となったため、炉頂から
装入している鉱石量90t/回を1.5t/回減らし、
そのまま操業を継続した場合であり、微粉炭吹込み操業
の基準操業2に対して、生産量低下、溶銑中のシリコン
上昇が大きい。In Comparative Example 2, during pulverized coal injection operation, the average value in the circumferential direction of the thermometer embedded in the furnace stave was 100%, which is the normal value.
Since the temperature was 80℃, which was outside of ±15℃, the amount of ore charged from the top of the furnace, which was 90t/time, was reduced by 1.5t/time.
This is the case where the operation continues as it is, and the production volume decreases and the silicon in the hot metal increases significantly compared to the standard operation 2 of pulverized coal injection operation.
(発明の効果)
以上説明したように、本発明は、炉頂から装入される鉄
鉱石と羽口から吹込まれる粉状鉄源の合計の量を高炉の
炉熱が安定するように調整することにより、生産量、溶
銑中のシリコンを一定に維持し、安定した溶銑の供給が
可能である。(Effects of the Invention) As explained above, the present invention adjusts the total amount of iron ore charged from the top of the furnace and powdered iron source injected from the tuyere so that the furnace heat of the blast furnace is stabilized. By doing so, production volume and silicon content in hot metal can be maintained constant, and a stable supply of hot metal can be achieved.
出 願 人 新日本製鐵株式会社Out wish Man Nippon Steel Corporation
Claims (1)
から鉄鉱石とコークスを交互に装入する操業法において
、炉頂から装入する鉄鉱石を減らす操作を行ったとき、
該鉄鉱石が羽口部に到達した後に、該鉄鉱石に相当する
量の粉状鉄源を、羽口部から高炉の内部に吹込むことを
特徴とする高炉操業法。(1) In an operating method in which powdered iron source is injected into the blast furnace from the tuyere and iron ore and coke are alternately charged from the top of the furnace, an operation was performed to reduce the amount of iron ore charged from the top of the furnace. When,
A blast furnace operating method characterized in that after the iron ore reaches the tuyere, a powdered iron source in an amount equivalent to the iron ore is injected into the blast furnace from the tuyere.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9299290A JPH03291314A (en) | 1990-04-10 | 1990-04-10 | Method for operating blast furnace |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9299290A JPH03291314A (en) | 1990-04-10 | 1990-04-10 | Method for operating blast furnace |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH03291314A true JPH03291314A (en) | 1991-12-20 |
Family
ID=14069866
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP9299290A Pending JPH03291314A (en) | 1990-04-10 | 1990-04-10 | Method for operating blast furnace |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH03291314A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100434736B1 (en) * | 2000-12-22 | 2004-06-07 | 주식회사 포스코 | Method for managing the top gas temperature in lowering the level of charge in the blast furnace |
-
1990
- 1990-04-10 JP JP9299290A patent/JPH03291314A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100434736B1 (en) * | 2000-12-22 | 2004-06-07 | 주식회사 포스코 | Method for managing the top gas temperature in lowering the level of charge in the blast furnace |
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