JPH0770617A - Method for repairing furnace bottom part in blast furnace - Google Patents
Method for repairing furnace bottom part in blast furnaceInfo
- Publication number
- JPH0770617A JPH0770617A JP21965493A JP21965493A JPH0770617A JP H0770617 A JPH0770617 A JP H0770617A JP 21965493 A JP21965493 A JP 21965493A JP 21965493 A JP21965493 A JP 21965493A JP H0770617 A JPH0770617 A JP H0770617A
- Authority
- JP
- Japan
- Prior art keywords
- electrodes
- brick
- furnace
- furnace bottom
- bricks
- 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.)
- Withdrawn
Links
Landscapes
- Blast Furnaces (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、炉底レンガの損耗を抑
制し、長期間にわたって高炉を健全な状態に維持する方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for suppressing wear of a bottom brick and maintaining a blast furnace in a healthy state for a long period of time.
【0002】[0002]
【従来の技術】高炉は、製銑手段として熱経済的に優れ
たものであるが、炉体及び付帯設備を構築するために長
期間の作業を必要にすると共に、多額の設備負担を伴
う。設備費を含めた溶銑コストを下げるためには、高炉
の長寿命化が重要な条件となる。高炉の寿命は主として
炉底レンガの損耗度合いに応じて定まることから、長寿
命化を図る上で炉底レンガの損耗を抑える必要がある。
炉底レンガは、稼動面側に溶銑の凝固層が形成されてお
り、定常状態では溶銑と直接接触していない。しかし、
コークスフリー層の形成等によって熱負荷が増大した場
合,炉底部の冷却能が低下した場合等では、溶銑の凝固
層が溶解し、レンガに溶銑が直接接触するようになる。
溶銑との直接接触が続くと、炉底レンガの損耗が進行す
る。そこで、常に溶銑の凝固層が炉底レンガの稼動面側
に形成されているように、熱負荷に対応して炉底部を冷
却し、炉底レンガを保護する方法が従来から提案されて
いる。たとえば、底部に設けたパイプ内に所定量の水を
流すことにより、炉底底面を冷却している。また、散水
やステーブクーラ等によって、炉底側壁を冷却してい
る。何れの部位においても、冷え込みを防止するため、
冷却水供給量等を制御し、熱負荷に応じて冷却能を調整
している。2. Description of the Related Art Blast furnaces are excellent in terms of thermo-economics as a pig iron making means, but they require a long period of work for constructing a furnace body and incidental equipment, and entail a large amount of equipment burden. In order to reduce the hot metal cost including equipment cost, extending the life of the blast furnace is an important condition. Since the life of the blast furnace is determined mainly by the degree of wear of the bottom bricks, it is necessary to suppress the wear of the bottom bricks in order to extend the life.
In the furnace bottom brick, a solidified layer of hot metal is formed on the operating surface side, and in a steady state, it does not directly contact the hot metal. But,
When the heat load increases due to the formation of a coke-free layer or when the cooling capacity at the bottom of the furnace decreases, the solidified layer of hot metal melts and the hot metal comes into direct contact with the bricks.
If the direct contact with the hot metal continues, the wear of the bottom brick progresses. Therefore, a method of protecting the furnace bottom brick by cooling the furnace bottom portion in response to a heat load so that a solidified layer of hot metal is always formed on the operating surface side of the furnace bottom brick has been proposed. For example, the bottom surface of the furnace bottom is cooled by flowing a predetermined amount of water into a pipe provided at the bottom. Further, the side wall of the furnace bottom is cooled by water sprinkling or a stave cooler. In any part, to prevent cold,
The amount of cooling water supplied is controlled to adjust the cooling capacity according to the heat load.
【0003】[0003]
【発明が解決しようとする課題】従来の冷却方式では、
炉底や炉底側壁を構築する炉底レンガが一体的なもので
あると仮定して、熱負荷に対応した冷却能を算出してい
る。しかし、実際の炉底レンガは、流動状態の溶銑によ
る熱負荷や物理的衝撃を受け、特に目地部が損傷され易
く、レンガ間に空隙が発生する。レンガ間に生じた空隙
は、伝熱抵抗が大きく、炉底部の冷却能を悪化させる。
その結果、冷却水の流量をいくら増大させても、冷却効
果が炉底レンガの稼動面側まで到達せず、稼動面側が高
温状態のまま推移する。このような状態では、溶銑の凝
固層が溶解し、炉底レンガの損耗が促進される。したが
って、炉底レンガの損耗を抑制するため、炉底レンガ間
に生じた空隙を補修材で埋めることが必要とされる。し
かし、稼動中の高炉においてレンガ間に生じた空隙を検
出する有効な手段は、いままでのところ開発されていな
い。そのため、炉底レンガの保護を図るため炉底のいた
るところから頻繁に補修材を圧入する結果、多大の補修
コストや補修作業を余儀なくされていた。本発明は、こ
のような問題を解消すべく案出されたものであり、電気
抵抗値の変化からレンガ間の空隙発生箇所を検出し、こ
の検出結果に基づき補修材を圧入することにより、タイ
ムリーで且つ効果的に炉底レンガを補修し、炉底を保護
することを目的とする。In the conventional cooling system,
The cooling capacity corresponding to the heat load is calculated by assuming that the bottom bricks that construct the bottom and the side walls of the bottom are integrated. However, an actual hearth bottom brick is subjected to a heat load or physical shock due to molten pig iron in a fluidized state, and particularly, a joint portion is easily damaged, and a void is generated between the bricks. The voids generated between the bricks have a large heat transfer resistance and deteriorate the cooling capacity of the furnace bottom.
As a result, no matter how much the flow rate of the cooling water is increased, the cooling effect does not reach the operating surface side of the furnace bottom brick, and the operating surface side remains in a high temperature state. In such a state, the solidified layer of the hot metal melts and the wear of the furnace bottom brick is accelerated. Therefore, in order to suppress the wear of the hearth bricks, it is necessary to fill the voids generated between the hearth bricks with a repair material. However, an effective means for detecting voids between bricks in an operating blast furnace has not been developed so far. Therefore, as a result of frequently press-fitting the repair material from all over the furnace bottom in order to protect the furnace bottom brick, a large amount of repair cost and repair work have been forced. The present invention has been devised to solve such a problem, by detecting the void occurrence location between the bricks from the change in the electrical resistance value, by press-fitting repair material based on this detection result, The purpose is to protect the bottom of the furnace by repairing the bottom brick effectively and effectively.
【0004】[0004]
【課題を解決するための手段】本発明の補修方法は、そ
の目的を達成するため、炉底レンガ内の複数箇所に電極
を差し込み、炉底レンガを介した隣接電極間の間の電気
抵抗を定期的に測定し、該電気抵抗が増大する傾向が検
出された電極の周辺に設けられている開口部から補修材
を前記炉底レンガ内に圧入することを特徴とする。ま
た、鉄皮の複数箇所に電極を装着し、電極と鉄皮との間
の電気抵抗を定期的に測定し、この測定結果を炉底レン
ガに差し込んだ電極で得られた電気抵抗の測定結果に加
味しても良い。高炉の炉底部には、図1に模式的に示す
ように、冷却能を高くするためカーボン系のレンガ1が
数段にわたって積み上げられている。これらレンガ1の
うち、所定位置にあるレンガ1に電極2を挿入する。電
極2は、図2に示すように、絶縁物3で被覆された導体
4からケーブル5を引き出している。電極2は、レンガ
1に形成されている挿入孔6に差し込まれ、導体4が一
か所でレンガ1と接触する。In order to achieve the object, a repairing method of the present invention is to insert electrodes into a plurality of locations in a hearth brick to reduce the electric resistance between adjacent electrodes through the hearth brick. It is characterized in that the repair material is press-fitted into the furnace bottom brick through an opening provided around the electrode, which is periodically measured and the tendency of which the electric resistance increases is detected. In addition, the electrodes were attached to the iron skin at multiple points, the electrical resistance between the electrode and the iron skin was periodically measured, and the measurement results of the electrical resistance obtained by the electrodes inserted into the furnace bottom brick were measured. You may add it to. As schematically shown in FIG. 1, carbon-based bricks 1 are piled up in several steps at the bottom of the blast furnace in order to enhance the cooling capacity. The electrode 2 is inserted into the brick 1 at a predetermined position among these bricks 1. As shown in FIG. 2, the electrode 2 pulls out a cable 5 from a conductor 4 covered with an insulator 3. The electrode 2 is inserted into the insertion hole 6 formed in the brick 1, and the conductor 4 contacts the brick 1 at one place.
【0005】導体4としては、高温に耐え且つ導電性を
呈するものである限り、材質の制約を受けない。しか
し、熱伝導率や熱膨張率を考慮するとき、カーボンレン
ガ1と同材質である炭素系電極を使用することが好まし
い。絶縁物3としては、導電性がなく、耐熱性をもつも
のである限り、どのような材質でも使用できる。個々の
電極2から引き出したケーブル5は、図1に示すように
一か所に集められ、それぞれ電気抵抗測定器7に接続さ
れる。電気抵抗測定器7からの出力を観察又は記録する
ことにより、各電極2間の経時変化が把握される。この
経時変化から、レンガ1間に空隙が発生したか否かが判
定される。空隙は、レンガ1と鉄皮8との間に生じるこ
ともある。そこで、鉄皮8に対しても電極を取り付け、
同様に鉄皮8とレンガ1間の電気抵抗を測定し、その経
時変化を観察又は記録する。The conductor 4 is not restricted by the material as long as it can withstand high temperatures and exhibits conductivity. However, when considering the thermal conductivity and the coefficient of thermal expansion, it is preferable to use a carbon-based electrode made of the same material as the carbon brick 1. As the insulator 3, any material can be used as long as it is not conductive and has heat resistance. The cables 5 drawn out from the individual electrodes 2 are gathered in one place as shown in FIG. 1, and are connected to the electric resistance measuring device 7, respectively. By observing or recording the output from the electric resistance measuring device 7, the change with time between the electrodes 2 can be grasped. From this change over time, it is determined whether or not a void has occurred between the bricks 1. Voids may occur between the brick 1 and the iron skin 8. Therefore, attach the electrode also to the iron skin 8,
Similarly, the electric resistance between the iron skin 8 and the brick 1 is measured, and the change with time thereof is observed or recorded.
【0006】[0006]
【作用】電極1間の電気抵抗は、その領域の温度変化に
より増減する。しかし、レンガ−レンガ間やレンガ−鉄
皮間に空隙が発生すると、エアギャップによって熱伝導
率が著しく低下し、レンガの稼動面側が高温状態にな
る。エアギャップの発生は、同時に電気抵抗を大幅に上
昇される。この電気抵抗の上昇は、温度変化に起因する
電気抵抗の変動に比較して遥かに大きい。したがって、
炉底部の複数箇所に設置された電極2で各部間の電気抵
抗を測定し、その経時変化をみるとき、空隙の発生が明
確に検出される。The electrical resistance between the electrodes 1 increases or decreases depending on the temperature change in the area. However, when voids are generated between the bricks or between the bricks and the iron shell, the thermal conductivity is significantly reduced due to the air gap, and the working surface side of the bricks is in a high temperature state. The occurrence of an air gap simultaneously increases the electrical resistance significantly. This increase in the electric resistance is much larger than the change in the electric resistance caused by the temperature change. Therefore,
When the electric resistance between the respective parts is measured by the electrodes 2 installed at a plurality of places on the bottom of the furnace and the change with time is observed, the generation of voids is clearly detected.
【0007】電気抵抗の急激な上昇がみられた箇所は、
空隙が発生している箇所である。したがって、この箇所
に補修材9を圧入するとき、発生した空隙を効果的に埋
めることができる。空隙発生箇所は、炉底に挿入する電
極2の個数が多いほど、高い精度で検出される。しか
し、電極2の個数増加に伴って設備費用の上昇を招くこ
とから、空隙発生データに関する過去の実績等を勘案
し、必要に応じて電極の設置個数及び設置位置を選定す
ることが好ましい。他方、電気抵抗に大きな変動がみら
れない箇所では、レンガ1ーレンガ1間やレンガ1ー鉄
皮8間に空隙が発生していない。この箇所に補修材を圧
入しようとしても、圧入材が入らず無駄な作業になる。
この点、本発明においては、空隙発生の有無が明確に区
別できることから、空隙発生箇所にのみ補修材が圧入さ
れ、高い作業効率で炉底部の補修が行われる。The place where the electric resistance is suddenly increased is
It is a place where a void is generated. Therefore, when the repair material 9 is press-fitted into this portion, the generated void can be effectively filled. The larger the number of electrodes 2 to be inserted into the furnace bottom, the higher the accuracy at which the voids are generated will be detected. However, since the equipment cost increases as the number of the electrodes 2 increases, it is preferable to select the number of electrodes to be installed and the position of the electrodes as necessary in consideration of the past record regarding the void generation data. On the other hand, no void is generated between the brick 1 and the brick 1 or between the brick 1 and the iron crust 8 at a portion where the electric resistance does not change significantly. Even if an attempt is made to press-fit the repair material into this portion, the press-fitting material does not enter, resulting in useless work.
In this respect, in the present invention, since the presence / absence of voids can be clearly distinguished, the repair material is press-fitted only into the voids, and the furnace bottom is repaired with high work efficiency.
【0008】[0008]
【実施例】炉内容積1650m3 の高炉の炉底側壁10
に、図3に示すように円周方向に関して等間隔で6本の
電極211,212,213・・・216を挿入した。炉底側壁
10に対する電極211,212,213・・・216の挿入深
度は、300mmに設定した。また、電極211,212,
213・・・216間の中間位置で、電極221,222,223
・・・226を鉄皮8と接触して取り付けた。電極211,
212,213・・・216及び電極221,222,223・・・
226をそれぞれケーブル5を介して電気抵抗測定器7に
接続し、互いに隣り合う電極間及び鉄皮ー電極間の電気
抵抗を8時間間隔で測定した。測定結果の一部を、図4
に示す。[Example] Furnace bottom side wall 10 of a blast furnace having an inner volume of 1650 m 3
Then, as shown in FIG. 3, six electrodes 2 11 , 2 12 , 2 13 ... 2 16 were inserted at equal intervals in the circumferential direction. The insertion depth of the electrodes 2 11 , 2 12 , 2 13 ... 2 16 into the furnace bottom side wall 10 was set to 300 mm. In addition, the electrodes 2 11 , 2 12 ,
At an intermediate position between 2 13 ... 2 16 the electrodes 2 21 , 2 22 , 2 23
... 2 26 was attached in contact with the iron skin 8. Electrode 2 11 ,
2 12 , 2 13 ... 2 16 and electrodes 2 21 , 2 22 , 2 23 ...
2 26 was connected to the electric resistance measuring device 7 via the cable 5 respectively, and the electric resistances between the electrodes adjacent to each other and between the iron-sheath electrodes were measured at intervals of 8 hours. Fig. 4 shows a part of the measurement results.
Shown in.
【0009】本実施例の操業では、図4に示すように、
電極214と電極215との間の電気抵抗及び電極224と電
極215との間の電気抵抗に上昇傾向がみられ、経過日数
5日で高い電気抵抗が示された。このことから、電極2
24と電極215との間にある炉底レンガに空隙が発生した
ことが判る。他方、電極215と電極216との間の電気抵
抗及び電極225と電極216との間の電気抵抗には、空隙
発生に起因する変動が実質的にみられなかった。そこ
で、電極224と電極215との間に位置する圧入口から、
休風日にタール系補修材を3時間で100kg充填し
た。圧入材充填後の高炉を操業を継続したとき、電極2
14と電極215との間の電気抵抗及び電極224と電極215
との間の電気抵抗が急激に当初の値まで低下した。この
ことから、電極224と電極215との間にある炉底レンガ
に発生した空隙が補修材で埋められ、炉底レンガが補修
されたことが判る。In the operation of this embodiment, as shown in FIG.
The electric resistance between the electrode 2 14 and the electrode 2 15 and the electric resistance between the electrode 2 24 and the electrode 2 15 tended to increase, and a high electric resistance was shown after 5 days elapsed. From this, the electrode 2
It can be seen that a void was generated in the hearth brick between 24 and electrode 2 15 . On the other hand, the electric resistance between the electrodes 2 15 and 2 16 and the electric resistance between the electrodes 2 25 and 2 16 did not substantially fluctuate due to the generation of voids. Therefore, from the pressure inlet located between the electrodes 2 24 and 2 15
On a breeze day, 100 kg of a tar-based repair material was filled in 3 hours. When the operation of the blast furnace after filling the press-fit material is continued, the electrode 2
Electrical resistance between 14 and electrode 2 15 and electrode 2 24 and electrode 2 15
The electrical resistance between and suddenly dropped to the initial value. From this, it is understood that the voids generated in the hearth brick between the electrodes 2 24 and 2 15 were filled with the repair material, and the hearth brick was repaired.
【0010】[0010]
【発明の効果】以上に説明したように、本発明において
は、レンガーレンガ間及び/又はレンガー鉄皮間の電気
抵抗を測定し、電気抵抗の経時変化から炉底レンガの空
隙発生及び発生箇所を検出している。電気抵抗の急激な
経時変化は、どこのレンガ間又はレンガー鉄皮間に空隙
が発生したかを正確に表している。そのため、電気抵抗
の経時変化に基づき、補修材を圧入する箇所を特定し、
補修材を圧入するとき、タイムリーに且つ効果的に炉底
レンガを補修することができる。その結果、炉底部の熱
伝導が常に良好な状態に保たれ、溶銑の溶解等に起因し
た炉底レンガの損耗が抑制される。As described above, in the present invention, the electric resistance between bricks and bricks and / or between the bricks and the iron shell is measured, and the generation of voids in the furnace bottom brick and the generation location are detected from the change with time of the electric resistance. is doing. The abrupt change of the electric resistance with time accurately indicates where between the bricks or between the brick and the iron crust a void is generated. Therefore, based on the change over time of the electrical resistance, identify the place to press fit the repair material,
When press-fitting the repair material, the furnace bottom brick can be repaired in a timely and effective manner. As a result, the heat conduction at the bottom of the furnace is always maintained in a good state, and the wear of the brick at the bottom of the furnace due to the melting of the hot metal is suppressed.
【図1】 高炉炉底部に電極を挿入した模式図Fig. 1 Schematic diagram of electrodes inserted in the bottom of the blast furnace
【図2】 炉底レンガに対する電極の挿入状態[Fig. 2] State of insertion of electrodes into the bottom brick
【図3】 本発明実施例において複数の電極を装着して
炉底側壁FIG. 3 is a furnace bottom side wall in which a plurality of electrodes are mounted in the embodiment of the present invention.
【図4】 各電極で測定されたレンガ間及びレンガー鉄
皮間の電気抵抗の経時変化を示したグラフFIG. 4 is a graph showing changes over time in electric resistance between bricks and between bricks and iron skin measured at each electrode.
1:カーボン系のレンガ 2:電極 3:絶縁体
4:導体 5:ケーブル 6:レンガに開けた挿
入孔 7:電気抵抗測定器 8:鉄皮 9:補修
材 10:炉底側壁 211,212,213・・・216:レンガに差し込んだ電極 221,222,223・・・226:鉄皮に接触して取り付け
た電極1: Carbon brick 2: Electrode 3: Insulator
4: Conductor 5: Cable 6: Insertion hole opened in brick 7: Electric resistance measuring instrument 8: Iron skin 9: Repair material 10: Side wall of furnace bottom 2 11 , 2 12 , 2 13 ... 2 16 : Inserted in brick Electrode 2 21 , 2 22 , 2 23, ... 2 26 : Electrode attached in contact with the iron skin
Claims (2)
み、炉底レンガを介した隣接電極間の間の電気抵抗を定
期的に測定し、該電気抵抗が増大する傾向が検出された
電極の周辺に設けられている開口部から補修材を前記炉
底レンガ内に圧入することを特徴とする高炉炉底部の補
修方法。1. An electrode in which electrodes are inserted into a plurality of locations in a hearth brick, electric resistances between adjacent electrodes through the hearth bricks are periodically measured, and a tendency in which the electric resistance increases is detected. A method for repairing the bottom of a blast furnace, wherein a repair material is press-fitted into the brick of the furnace bottom through an opening provided in the periphery of the furnace.
み、且つ鉄皮の複数箇所に電極を装着し、炉底レンガを
介した隣接電極間及び/又は電極と鉄皮との間の電気抵
抗を定期的に測定し、該電気抵抗が増大する傾向が検出
された電極の周辺に設けられている開口部から補修材を
前記炉底レンガ内に圧入することを特徴とする高炉炉底
部の補修方法。2. Electricity between adjacent electrodes and / or between the electrodes and the iron shell through the hearth brick by inserting electrodes into the furnace bottom brick at a plurality of locations and attaching electrodes to the iron shell at a plurality of locations. The resistance is measured regularly, and the repair material is press-fitted into the furnace bottom brick from an opening provided in the periphery of the electrode in which the tendency that the electric resistance is increased is detected. Repair method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21965493A JPH0770617A (en) | 1993-09-03 | 1993-09-03 | Method for repairing furnace bottom part in blast furnace |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21965493A JPH0770617A (en) | 1993-09-03 | 1993-09-03 | Method for repairing furnace bottom part in blast furnace |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH0770617A true JPH0770617A (en) | 1995-03-14 |
Family
ID=16738895
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP21965493A Withdrawn JPH0770617A (en) | 1993-09-03 | 1993-09-03 | Method for repairing furnace bottom part in blast furnace |
Country Status (1)
Country | Link |
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JP (1) | JPH0770617A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109631588A (en) * | 2019-01-31 | 2019-04-16 | 王贵江 | A kind of method for maintaining of all-electric melting kiln |
-
1993
- 1993-09-03 JP JP21965493A patent/JPH0770617A/en not_active Withdrawn
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN109631588A (en) * | 2019-01-31 | 2019-04-16 | 王贵江 | A kind of method for maintaining of all-electric melting kiln |
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A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20001107 |