JP2612162B2 - Blast furnace operation method - Google Patents
Blast furnace operation methodInfo
- Publication number
- JP2612162B2 JP2612162B2 JP61149959A JP14995986A JP2612162B2 JP 2612162 B2 JP2612162 B2 JP 2612162B2 JP 61149959 A JP61149959 A JP 61149959A JP 14995986 A JP14995986 A JP 14995986A JP 2612162 B2 JP2612162 B2 JP 2612162B2
- Authority
- JP
- Japan
- Prior art keywords
- blast furnace
- heavy oil
- slurry
- tuyere
- iron 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 - Lifetime
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B5/00—Making pig-iron in the blast furnace
- C21B5/001—Injecting additional fuel or reducing agents
- C21B5/003—Injection of pulverulent coal
- C21B5/004—Injection of slurries
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Iron (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 この発明は、荷下がり安定下において高炉の溶銑中Si
濃度を低減させることができる高炉操業方法に係り、よ
り詳しくは高炉羽口から鉄鉱石粉をスラリー状にして吹
込むことによって、コークス比低下、炉内脱珪反応促進
をはかり低Si操業の安定化をはかる高炉操業方法に関す
る。The present invention relates to a method for producing Si in molten iron of a blast furnace under stable unloading.
Regarding the blast furnace operating method that can reduce the concentration, more specifically, stabilize the low Si operation by lowering the coke ratio and promoting the desiliconization reaction in the furnace by blowing iron ore powder in slurry form from the tuyere of the blast furnace. The present invention relates to a method of operating a blast furnace.
技術的背景 高炉内における溶銑中へのSi移行は、炉内湯溜部にお
けるスラグ−メタル反応よりもむしろSiOガスを媒介と
するガス−メタル反応が主要な役割を果たしている。Technological background The transfer of Si into the hot metal in the blast furnace plays a major role in the gas-metal reaction mediated by SiO gas, rather than in the slag-metal reaction in the furnace basin.
SiOガスを媒介とする溶銑中へのSiの移行は、次の２
つの過程に大別される（鉄と鋼Vol58 1972 219頁）。The transfer of Si into hot metal mediated by SiO gas is as follows:
(Iron and Steel Vol 58, 1972, p. 219).
すなわち、レースウエイ近傍の高温低酸素分圧領域
におけるコークス中の灰分を主源とするSiO2とコークス
中の固定炭素との反応によるSiOガスの生成過程、軟
化融着帯以下における上昇ガス流中に含まれるSiOガス
と滴下している溶銑中の炭素との反応による溶銑中への
Si移行過程であり、この両過程を反応式で表わすと以下
のようになる。That is, the process generation of SiO gas by reaction with fixed carbon of SiO 2 and coke to the ash in the coke in the high temperature and low oxygen partial pressure region of raceways near a main source, increase the gas stream in the cohesive zone below Of molten iron into the hot metal by the reaction between the SiO gas contained in
This is the Si transfer process, and both processes are represented by the following reaction formulas.
（SiO2）＋Ｃ＝SiO（ｇ）＋CO（ｇ） …式 SiO（ｇ）＋Ｃ＝Si＋CO（ｇ） …式 ここで、（）はその化合物がスラグ中に存在すること
を示す慣用表記法であり、元素名の下線はその成分が溶
銑中に存在することを示す慣用表記法である。(SiO 2 ) + C = SiO (g) + CO (g) Formula SiO (g) + C = Si + CO (g) Formula Here, () is a conventional notation indicating that the compound is present in slag. The underline of the element name is a conventional notation that indicates that the component is present in the hot metal.
したがって、溶銑中Si濃度の制御方法としては、SiO
ガス発生反応の制御と溶銑中へのSi移行反応の制御とが
ある。Therefore, the control method of the Si concentration in the hot metal is SiO
There are control of gas generation reaction and control of Si transfer reaction into hot metal.
実際の高炉操業において、前者の制御手段としては、
コークス中の灰分量の制御による羽口前持込みSiO2量の
制御や羽口前温度制御によるSiOガス発生速度の制御等
が実施されている。後者の制御手段としては、装入物分
布制御に基づいたコークス比制御による融着帯レベルの
管理や焼結鉱の被還元性・軟化融着帯性状制御による融
着帯レベルの制御等がある（鉄と鋼Vol68 1982 219
頁）。In actual blast furnace operation, the former control means
Control of the SiO gas generation rate is implemented by the control and blade preoral temperature control blade preoral bringing SiO 2 amount by the control of the ash content in the coke. As the latter control means, there is control of the cohesive zone level by controlling the coke ratio based on the charge distribution control, control of the cohesive zone level by controlling the reducible and softened cohesive zone properties of the sinter, and the like. (Iron and steel Vol68 1982 219
page).
従来技術とその問題点 溶銑中Si濃度の制御方法としては、上記の高炉内で溶
銑中へのSi移行メカニズムに立脚した制御手段以外に、
送風羽口から酸化鉄を吹込み、下記式の反応によって
溶銑中Siを酸化させる、いわゆる炉内脱珪手段が開発さ
れている（特開昭56−29601、特開昭51−77508）。Conventional technology and its problems As a method for controlling the Si concentration in the hot metal, in addition to the control means based on the Si transfer mechanism into the hot metal in the blast furnace described above,
So-called desiliconization means in furnaces have been developed in which iron oxide is blown from a blowing tuyere to oxidize Si in hot metal by a reaction of the following formula (JP-A-56-29601 and JP-A-51-77508).
Si＋2FeO＝（SiO2）＋2Fe …式 この制御手段の場合、上記反応が適切に制御されれ
ば、出銑直前での溶銑中Si濃度の制御が可能であり、溶
銑中Si濃度の管理が容易に実施できる。Si + 2FeO = (SiO 2 ) + 2Fe In the case of this control means, if the above reaction is appropriately controlled, the Si concentration in the hot metal immediately before tapping can be controlled, and the Si concentration in the hot metal can be easily controlled. Can be implemented.
しかしながら、従来の気体輸送による羽口からの酸化
鉄吹込みによる溶銑中Si濃度の制御方法は、粉末乾燥設
備および運転費が高くつきコスト的に不利であること、
また輸送配管系、特に分配器および曲管部における摩耗
が進展し長期的な安定稼働が困難であるという問題があ
った。However, the conventional method of controlling the concentration of Si in hot metal by injecting iron oxide from tuyeres by gas transportation is disadvantageous in terms of cost due to high powder drying equipment and operation costs,
In addition, there is a problem that abrasion in the transport piping system, particularly in the distributor and the curved pipe portion, progresses, and it is difficult to perform long-term stable operation.
かかる対策として、特開昭60−258403号公報には、粉
状の酸化鉄を水と混合し酸化鉄スラリーとして高炉羽口
から吹込む方法が提案されている。しかし、この方法で
は溶銑中Si含有量の低下、配管および羽口の摩耗減少の
効果は得られても、酸化鉄をスラリー状にするのに水を
用いているため水の分解熱を必要とし、コークス比が著
しく悪化するという問題がある。As a countermeasure, Japanese Patent Application Laid-Open No. 60-258403 proposes a method in which powdery iron oxide is mixed with water and is blown from a blast furnace tuyere as an iron oxide slurry. However, although this method has the effect of reducing the Si content in the hot metal and reducing the wear of pipes and tuyeres, it requires the heat of decomposition of water because it uses water to make the iron oxide into a slurry. However, there is a problem that the coke ratio is significantly deteriorated.
発明の目的 この発明は、製鋼工程での造滓剤使用量の低減を目的
とした高炉操業法における従来の前記問題点を解決する
ためになされたものであり、粉体乾燥を必要とせず、配
管摩耗を起すことなく、羽口からの粉鉄鉱石吹込みを可
能とするのみならず、コークス比の低減結果と、荷下が
り安定下で大きなSi操業効果を得ることが可能な高炉操
業方法を提供せんとするものである。Object of the invention This invention has been made in order to solve the above-mentioned conventional problems in the blast furnace operating method for the purpose of reducing the amount of slag-forming agent used in the steelmaking process, without the need for powder drying, A blast furnace operating method that not only enables the injection of fine iron ore from the tuyeres without causing pipe abrasion, but also reduces the coke ratio and achieves a large Si operating effect with stable unloading. It will not be provided.
問題点を解決するための手段 この発明は、鉄鉱石粉と重油とを混合してスラリー状
とし、この鉄鉱石粉・重油スラリーを高炉羽口から吹込
むことによって、羽口前での重油の燃焼により吹込み鉱
石の還元・溶融を促進し、コークス比の低減、荷下がり
安定化および大きなSi低減効果を得るとともに、配管摩
耗防止等の効果も同時に得ることができる方法である。Means for Solving the Problems The present invention relates to a method in which iron ore powder and heavy oil are mixed to form a slurry, and the iron ore powder / heavy oil slurry is blown from a blast furnace tuyere to burn heavy oil in front of the tuyere. This is a method that promotes the reduction and melting of blown ore, reduces the coke ratio, stabilizes the unloading, and greatly reduces the Si, and can also simultaneously achieve the effects of preventing pipe abrasion.
ここで、鉄鉱石粉の高炉吹込み方法として、重油スラ
リー方式を採用したのは、以下に示す理由による。Here, the reason why the heavy oil slurry method was adopted as the method for blowing the iron ore powder into the blast furnace was as follows.
すなわち、羽口前での重油の燃焼により吹込み鉱石
の還元・溶融が促進されること、シャフト下部におい
て水素還元反応が進行するために鉱石類の溶融滴下性状
を好転させる、レースウエイ近傍でのコークス粉量を
低下させるため荷下がりが安定する、重油が羽口に吹
込まれるため高炉のコークス比低減に寄与する、粉体
の乾燥設備費および運転費が不要となり、コスト的に気
体輸送に比べ有利である、配管摩耗が防止され長期的
に安定して粉体の供給が可能となるという効果が得られ
るからである。In other words, the reduction and melting of blown ore is promoted by the combustion of heavy oil in front of the tuyere, and the hydrogen reduction reaction proceeds at the lower part of the shaft to improve the melting and dropping properties of the ore. Lowering the amount of coke powder stabilizes unloading. Heavy oil is blown into the tuyere, contributing to a reduction in the coke ratio of the blast furnace. This is because it is advantageous in that abrasion of the pipe is prevented and the powder can be supplied stably over a long period of time.
一方、高炉操業は昭和40年代、羽口から重油、タール
等の液体燃料を多量に吹込むことにより低コークス比、
高出銑比操業が指向されてきた。その後、昭和50年代前
半、原油価格の高騰によりエネルギー価格体系が大きく
変化し、高炉操業はオールコークス操業が主流となって
きた。On the other hand, in blast furnace operation, in the 1960s, a large amount of liquid fuel such as heavy oil and tar was injected from tuyere to reduce coke ratio,
High output ratio operation has been pursued. After that, in the early 1950s, the rise in crude oil prices drastically changed the energy price system, and blast furnace operations became dominated by all-coke operations.
しかし、昭和60年代後半より、円高の影響および産油
国の原油価格引下げに伴い、再び製鉄工程においてエネ
ルギー源として重油を使用コークス比に下げる方がコス
ト的に有利な状況も現れてきている。However, from the latter half of the 1960s, due to the impact of the strong yen and the lowering of crude oil prices in oil-producing countries, it has become more cost-effective to reduce the use of heavy oil as an energy source in the iron making process to a lower coke ratio.
したがって、鉄鉱石粉・重油スラリーは、前記粉体供
給系のメリットだけでなく、高炉操業上も非常に有効で
ある。Therefore, the iron ore powder / heavy oil slurry is very effective not only in the merit of the powder supply system but also in blast furnace operation.
すなわち、重油スラリー吹込みによる水素投入量の上
昇は、羽口前温度低下による低Si操業に対して有効であ
るとともに、シャフト下部において水素還元反応が進行
するために鉱石類の溶融滴下性状を好転させる効果を奏
し、さらにレースウエイ近傍でのコークス粉量を低下さ
せるため荷下がり安定化に大きく寄与する。In other words, an increase in the amount of hydrogen injected due to the injection of heavy oil slurry is effective for low Si operation due to a decrease in the temperature in front of the tuyere, and also improves the melting and dropping properties of ores because the hydrogen reduction reaction proceeds at the lower part of the shaft. This has the effect of reducing the amount of coke powder in the vicinity of the raceway, which greatly contributes to stabilization of unloading.
また、重油スラリー吹込みにおいては、鉄鉱石粉とと
もに重油が羽口に吹込まれるため、高炉のコークス比低
減に寄与する。Further, in the heavy oil slurry injection, heavy oil is injected into the tuyere together with the iron ore powder, thereby contributing to a reduction in the coke ratio of the blast furnace.
なお、鉄鉱石粉と重油の混合割合は、スラリーの液性
限界内であれば特に限定するものではなく、鉄鉱石粉で
大略80重量％まで可能である。したがって、両者の比率
はこの範囲内において製銑サイドのニーズ（溶銑中Si制
御・コークス比低減）に基づいて決定される。The mixing ratio of iron ore powder and heavy oil is not particularly limited as long as it is within the liquid limit of the slurry, and can be up to about 80% by weight in iron ore powder. Therefore, the ratio of the two is determined within this range based on the needs of the ironmaking side (Si control in hot metal and reduction of coke ratio).
発明の図面による開示 第１図はこの発明の一実施例を示す概略図であり、１
はサービスホッパー、２はロータリーフィーダー、３は
ミキシングタンク、４は重油供給ライン、５はスラリー
ポンプ、６は分配器、７はスラリー吹込みノズル、８は
羽口、９は高炉をそれぞれ示す。FIG. 1 is a schematic diagram showing an embodiment of the present invention.
Denotes a service hopper, 2 denotes a rotary feeder, 3 denotes a mixing tank, 4 denotes a heavy oil supply line, 5 denotes a slurry pump, 6 denotes a distributor, 7 denotes a slurry injection nozzle, 8 denotes a tuyere, and 9 denotes a blast furnace.
すなわち、サービスホッパー１内に貯蔵された鉄鉱石
粉は、該ホッパー下部に設けられたロータリーフィーダ
ー２を介して所定量切出されてミキシングタンク３内に
供給され、該ミキシングタンク内で重油供給ライン４よ
り供給される所定量の重油と均一に混合され、所定濃度
の鉄鉱石粉・重油スラリーに調整される。しかる後、ミ
キシングタンク３下部からスラリーポンプ５により分配
器６を介して各羽口８に分配・流送され、スラリー吹込
みノズル７より高炉９内に吹込まれる。That is, the iron ore powder stored in the service hopper 1 is cut out by a predetermined amount through a rotary feeder 2 provided at a lower portion of the hopper, supplied to a mixing tank 3, and supplied to a heavy oil supply line 4 in the mixing tank. It is uniformly mixed with a predetermined amount of heavy oil supplied from the above, and adjusted to a predetermined concentration of iron ore powder / heavy oil slurry. Thereafter, the slurry is supplied from the lower portion of the mixing tank 3 to each tuyere 8 by the slurry pump 5 via the distributor 6 and is then fed into the blast furnace 9 from the slurry injection nozzle 7.
なお、スラリー吹込みノズル７は各羽口に設置されて
おり、分配器６は必要に応じて１つ以上複数個、場合に
よっては多段で設置されている。また、サービスホッパ
ー１からスラリーポンプ５までの系統は、１つ以上出銑
口方向別に必要に応じて複数設置されている。In addition, the slurry injection nozzle 7 is installed in each tuyere, and one or more distributors 6 are installed as needed, and in some cases, multiple stages are installed. In addition, one or more systems from the service hopper 1 to the slurry pump 5 are installed as needed for each tap hole direction.
実施例 Ａ高炉（内容積5050m3）において、第１表に示す組成
の鉄鉱石粉を重油と混合して吹込んだ場合の結果を、従
来の気体輸送方式により吹込んだ場合と比較して第２表
に示す。Example A In a blast furnace (internal volume of 5050 m 3 ), the results of the case where iron ore powder having the composition shown in Table 1 was mixed with heavy oil and injected were compared with the results obtained when the ore powder was injected by the conventional gas transport method. The results are shown in Table 2.
本実施例は、溶銑中Si濃度の低減を目的として、期間
Ａでは従来の気体輸送による高炉羽口からの鉄鉱石粉吹
込みを実施した。その時の吹込み量は、40kg/p−Ｔで、
溶銑中Si濃度は0.17％まで低下したが、スリップ回数は
減らなかった。また、気体輸送による粉体吹込みのた
め、配管摩耗による設備トラブルが発生し、月間約４回
の輸送停止と設備補修を実施する必要があった。In this embodiment, in order to reduce the Si concentration in the hot metal, in the period A, the iron ore powder was injected from the blast furnace tuyere by the conventional gas transport. The blowing rate at that time is 40kg / p-T,
Although the Si concentration in the hot metal decreased to 0.17%, the number of slips did not decrease. In addition, due to powder injection by gas transportation, equipment troubles occurred due to pipe wear, and it was necessary to stop transportation and repair equipment about four times a month.
一方、期間Ｂではこの発明方法を適用し、鉄鉱石粉・
重油スラリーの高炉吹込みを実施した。その際、スラリ
ー中の鉄鉱石粉量は40kg/p−Ｔ、重油量は30kg/p−Ｔに
設定し、トータル70kg/p−Ｔの鉄鉱石粉・重油スラリー
を吹込んだ。On the other hand, in the period B, the method of the present invention was applied to
Blast furnace injection of heavy oil slurry was performed. At that time, the amount of iron ore powder in the slurry was set to 40 kg / p-T, the amount of heavy oil was set to 30 kg / p-T, and a total of 70 kg / p-T of iron ore powder / heavy oil slurry was blown.
その結果、溶銑中Si濃度が0.16％まで低下するととも
に、高炉水素投入量が8.1kg/p−Ｔまで上昇したため、
高炉内の装入物荷下がりは安定化し、スリップ回数は低
下した。さらに、コークス比の低下をもたらし、エネル
ギーコスト低減がはかられた。As a result, the concentration of Si in the hot metal decreased to 0.16%, and the hydrogen input of the blast furnace increased to 8.1 kg / p-T.
The load drop in the blast furnace stabilized and the number of slips decreased. Furthermore, the coke ratio was reduced, and the energy cost was reduced.
また、本発明法は重油スラリー輸送であるため、配管
の摩耗は大幅に低減され、月１回の高炉定期休風時に設
備点検を実施することにより、設備トラブル発生なしに
連続運転が可能であった。In addition, since the method of the present invention uses heavy oil slurry transportation, the wear on the piping is greatly reduced, and by performing equipment inspections once a month when the blast furnace is regularly closed, continuous operation is possible without equipment trouble. Was.
なお、鉄鉱石粉を水と混合しスラリー状にして高炉に
吹込んだ場合には、輸送設備トラブル発生なしに連続運
転は可能であるが、高炉内では水の分解熱を必要とする
ためコークス比の悪化を余儀なくされることは明らかで
ある。When iron ore powder is mixed with water and slurried and blown into a blast furnace, continuous operation is possible without any trouble with transportation equipment. It is clear that this has to be worsened.
発明の効果 以上説明したごとく、この発明方法によれば、鉄鉱石
粉を重油スラリーとして羽口から吹込むことにより、配
管摩耗防止等の効果が得られるばかりでなく、羽口前で
の重油の燃焼により吹込み鉱石の還元・溶融が促進され
コークス比の低減がはかられ、かつ荷下がり安定化で長
期的に低Si操業を実施することが可能となり、高炉操業
の安定化と高効率化に大きく寄与するとともに、製鋼工
程での造滓剤使用量低減にも大きな効果を奏する。 Effect of the Invention As described above, according to the method of the present invention, by blowing iron ore powder as a heavy oil slurry from the tuyere, not only effects such as prevention of pipe wear can be obtained, but also combustion of heavy oil in front of the tuyere. Promotes the reduction and melting of blown ore, reduces the coke ratio, and stabilizes unloading to enable long-term low-Si operation, stabilizing blast furnace operation and increasing efficiency. In addition to making a significant contribution, it also has a significant effect on reducing the amount of slag-making agent used in the steelmaking process.
第１図はこの発明の一実施例を示す概略図である。 １……サービスホッパー ２……ロータリーフィーダー ３……ミキシングタンク ４……重油供給ライン ５……スラリーポンプ ６……分配器 ７……スラリー吹込みノズル ８……羽口 ９……高炉 FIG. 1 is a schematic view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Service hopper 2 ... Rotary feeder 3 ... Mixing tank 4 ... Heavy oil supply line 5 ... Slurry pump 6 ... Distributor 7 ... Slurry injection nozzle 8 ... Tuyere 9 ... Blast furnace
───────────────────────────────────────────────────── フロントページの続き (72)発明者 須山 真一 兵庫県尼崎市西長洲本通１丁目３番地 住友金属工業株式会社中央技術研究所内 (56)参考文献 特開 昭60−258403（ＪＰ，Ａ) 特開 昭53−87908（ＪＰ，Ａ) ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shinichi Suyama 1-3-3 Nishi-Nagasu Hondori, Amagasaki City, Hyogo Prefecture Inside the Central Research Laboratory, Sumitomo Metal Industries, Ltd. (56) References JP-A-60-258403 (JP, A ) JP-A-53-87908 (JP, A)
Claims (1)
し、この鉄鉱石粉・重油スラリーを高炉羽口から吹込む
ことを特徴とする高炉操業方法。1. A blast furnace operating method comprising mixing iron ore powder and heavy oil to form a slurry, and blowing the iron ore powder / heavy oil slurry from a blast furnace tuyere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61149959A JP2612162B2 (en) | 1986-06-26 | 1986-06-26 | Blast furnace operation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61149959A JP2612162B2 (en) | 1986-06-26 | 1986-06-26 | Blast furnace operation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS637305A JPS637305A (en) | 1988-01-13 |
| JP2612162B2 true JP2612162B2 (en) | 1997-05-21 |
Family
ID=15486341
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61149959A Expired - Lifetime JP2612162B2 (en) | 1986-06-26 | 1986-06-26 | Blast furnace operation method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2612162B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0676883B2 (en) * | 1988-05-18 | 1994-09-28 | 本田技研工業株式会社 | Optical sensor device |
| JP4837277B2 (en) * | 2004-11-30 | 2011-12-14 | シャープ株式会社 | Ranging sensor and equipment equipped with it |
| JP4206419B2 (en) | 2006-09-15 | 2009-01-14 | 友宏 秋山 | Ore processing method, ore processing equipment, iron making method, and iron and steel making method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5387908A (en) * | 1977-01-13 | 1978-08-02 | Nippon Steel Corp | Treating method for dust from iron manufacture |
| JPS60258403A (en) * | 1984-06-06 | 1985-12-20 | Sumitomo Metal Ind Ltd | Operating methof of blast furnace by blowing in slurry iron oxide |
-
1986
- 1986-06-26 JP JP61149959A patent/JP2612162B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS637305A (en) | 1988-01-13 |
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