JP2005248292A - Method for uniformizing level of pig slag in blast furnace - Google Patents

Method for uniformizing level of pig slag in blast furnace Download PDF

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JP2005248292A
JP2005248292A JP2004063451A JP2004063451A JP2005248292A JP 2005248292 A JP2005248292 A JP 2005248292A JP 2004063451 A JP2004063451 A JP 2004063451A JP 2004063451 A JP2004063451 A JP 2004063451A JP 2005248292 A JP2005248292 A JP 2005248292A
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blast furnace
potential difference
level
potential
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JP4313701B2 (en
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Kazuya Kunitomo
和也 国友
Koichi Yokoyama
浩一 横山
Takashi Orimoto
隆 折本
Masahito Sugiura
雅人 杉浦
Kiichiro Nakamura
毅一郎 中村
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Nippon Steel Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for uniformizing the level of pig slag and the flow of a molten metal in a furnace, through quickly detecting the formation of the nonuniform level of the pig slag and the nonuniform flow of the molten metal. <P>SOLUTION: The method for uniformizing the level of the pig slag in a blast furnace comprises: arranging a plurality of measurement points 11 for an electric potential at a spacing on the surface of a blast furnace shell 1 in a vertical direction; arranging potentiometers 12 for measuring a potential difference between the measurement points 11 for the electric potential, on a plurality of positions of a blast furnace body in the circumferential direction; determining a difference ΔE between a maximum potential difference and a minimum potential difference indicated in each potentiometer 12, at every timing of tapping; and taking an action against the blast furnace for correcting an amplitude of ΔE in accordance with the amplitude of ΔE in each potentiometer. The method further comprises arranging a plurality of the measurement points 11 for the electric potential on the bottom brick 5 of the blast furnace, in place of the surface of the blast furnace shell. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、高炉内の高炉円周方向における銑滓レベル及び炉内湯流れ状況を均一化する方法に関するものである。   The present invention relates to a method for equalizing the soot level in the blast furnace circumferential direction in the blast furnace and the state of hot water flow in the furnace.

高炉炉内において、原料となる鉄鉱石はコークスとともに炉頂から炉体内に供給され、羽口から炉体内に圧送される熱風によって温度が上昇し、コークスによって還元されて溶銑となる。溶銑は炉底部に貯留し、溶銑の上に接して溶滓（スラグ）が貯留する。高炉炉内に貯留した溶銑の最上部でかつ溶滓が存在する部位の高さ方向の位置を、ここでは銑滓レベルという。   In the blast furnace furnace, iron ore as a raw material is supplied from the top of the furnace together with coke into the furnace body, the temperature rises by hot air fed from the tuyere into the furnace body, and is reduced by the coke to form molten iron. The hot metal is stored at the bottom of the furnace, and the hot metal (slag) is stored in contact with the hot metal. The position in the height direction of the uppermost part of the hot metal stored in the blast furnace furnace and where the hot metal exists is referred to as the hot metal level here.

時間の経過とともに炉底部に貯留する溶銑量が増大し、銑滓レベルが上昇する。炉底部に設けられた出銑口を開口すると、溶銑及び溶滓が出銑口から炉外に導き出され、炉内の銑滓レベルが低下する。   As time passes, the amount of hot metal stored at the bottom of the furnace increases and the level of hot metal rises. When the tap hole provided in the bottom of the furnace is opened, the hot metal and the hot metal are led out of the furnace from the tap hole, and the level of the hot metal in the furnace is lowered.

炉内の銑滓レベルを検出する手段として、特許文献１では、高炉の炉底付近の炉壁を構成するレンガに、少なくとも１対の電極を設けて四端子測定法による抵抗測定系（ダブルブリッジ系）電気回路を構成し、電気抵抗の測定値から銑滓レベルを測定する方法が開示されている。この方法は、レンガと銑滓の電気抵抗を測定するため、レンガの経時的な劣化や銑滓のレンガへの浸入等に起因するレンガの導電性の変動、およびレンガ近傍の銑滓温度や銑滓の凝固状態または流動状態に起因する銑滓の導電性の変動などによりレンガと銑滓の電気抵抗の測定値は変動し、信頼性のある炉内銑滓レベルの測定データを得ることは困難である。   As a means for detecting the soot level in the furnace, in Patent Document 1, a resistance measuring system (double bridge) is provided by providing at least one pair of electrodes on a brick that constitutes the furnace wall near the bottom of the blast furnace and using a four-terminal measurement method. System) A method of constructing an electric circuit and measuring a wrinkle level from a measured value of electric resistance is disclosed. This method measures the electrical resistance between the brick and the fence, so that the conductivity of the brick due to the deterioration of the brick over time, the penetration of the fence into the brick, etc. The measured values of the electrical resistance of bricks and fences fluctuate due to fluctuations in the conductivity of the fence due to the solidification state or flow state of the fence, and it is difficult to obtain reliable measurement data for the level in the furnace It is.

高炉炉底部付近の鉄皮表面の高さ方向２個所間において電位差が検出され、その電位差は高炉炉内の銑滓レベルと関係があることが知られている。非特許文献１によると、測定点として炉底部及び羽口上部の鉄皮表面を用いて電位差を測定した結果、出銑の開始・終了のインターバルと測定した電位差の時間的変動との間に相関が見られる点が記載されている。検出される電位差は０．２ｍＶ前後であり、出銑口を閉鎖している間に電位差は０．１ｍＶほど増大し、出銑口を開いて出銑を行っている間に電位差は０．１ｍＶほど減少して元に戻る。   It is known that a potential difference is detected between two places in the height direction of the iron skin surface near the bottom of the blast furnace furnace, and the potential difference is related to the soot level in the blast furnace furnace. According to Non-Patent Document 1, as a result of measuring the potential difference using the iron bottom surface at the bottom of the furnace and the top of the tuyere as a measurement point, there is a correlation between the start and end intervals of the tapping and the temporal variation of the measured potential difference. The point where is seen is described. The detected potential difference is around 0.2 mV, the potential difference increases by about 0.1 mV while closing the tap and the potential difference is 0.1 mV while opening the tap. It decreases and returns to the original.

高炉炉底部の水平断面において、溶銑の湯流れは炉内いずれの部位においても均一であることが望ましい。しかし、水平断面におけるいずれかの部位において溶銑の湯流れが悪くなり、いわゆる不活性部位と呼ばれる領域が発生することがある。高炉炉壁から成長する粘稠層が高炉円周方向で不均一に発達したり、あるいは炉底部における空隙率が一部の部位のみ不均一に低下することが原因であると考えられている。このように高炉炉内で湯流れの不均一が発生すると、同時に銑滓レベルについても炉内で不均一化する。   In the horizontal section of the bottom of the blast furnace furnace, it is desirable that the hot metal flow is uniform in any part of the furnace. However, the hot metal flow of hot metal may deteriorate at any part of the horizontal section, and a so-called inactive part may be generated. It is thought that this is because the viscous layer that grows from the blast furnace wall develops unevenly in the circumferential direction of the blast furnace, or the porosity at the bottom of the furnace decreases nonuniformly only in some parts. Thus, when non-uniformity of the hot water flow occurs in the blast furnace, the soot level also becomes non-uniform in the furnace.

高炉内において銑滓レベルが不均一化して溶銑の湯流れが悪くなる不活性部位が発生すると、炉床部における湯流れの円周方向バランスが崩れ、出銑口毎の出銑量や出銑品質にばらつきが生じ、溶銑品質、炉体保護、操業安定性に重大な悪影響を及ぼすこととなる。従って、銑滓レベルの不均一化や湯流れの不均一化の発生を早期に検出し、不均一を是正するための操業アクションを行うことは、高炉操業安定化のために重要である。   If an inert part that makes the molten iron level uneven in the blast furnace and the molten metal flow becomes worse, the balance in the circumferential direction of the molten metal flow in the hearth is disrupted, and the amount of t Variations in quality will have a serious adverse effect on hot metal quality, furnace protection, and operational stability. Therefore, it is important for stabilizing the operation of the blast furnace to detect the occurrence of non-uniformity of the soot level and the non-uniformity of the molten metal flow at an early stage and to perform an operation action for correcting the non-uniformity.

従来、炉内の銑滓レベルの不均一化や湯流れの不均一化の発生については、複数の出銑口毎の出銑量や出銑温度、あるいはスラグ比（単位出銑量当たりの出滓量）、出滓率（出銑時間に占める出滓時間の割合）あるいは出銑速度、出滓速度の時系列推移から炉内湯流れ状況を推定するにとどまり、直接的な検知手段はなかった。   Conventionally, the occurrence of non-uniformity in the soot level in the furnace and non-uniformity in the flow of hot water has been explained by the amount of tapping, temperature, or slag ratio (output per unit tapping amount). The amount of hot water in the furnace was only estimated from the time-series transition of the output rate and the output rate (ratio of the output time in the output time) or the output speed and output speed, and there was no direct detection means. .

特開昭５９−１４０３０９号公報JP 59-140309 A Development & application of new techniques for blast furnace process control at SSAB Tunnplant, Lulea works. 1995 Ironmaking conference Proceedings pp271 - 279Development & application of new techniques for blast furnace process control at SSAB Tunnplant, Lulea works. 1995 Ironmaking conference Proceedings pp271-279

炉内の銑滓レベルの不均一化や湯流れの不均一化の発生については上記従来の炉内状況の推定にとどまるため、熟練炉前作業者の経験と勘に頼るところが大きく、正確な炉内状況の把握が困難であるという問題があった。   The occurrence of non-uniformity of the soot level in the furnace and the non-uniformity of the molten metal flow is limited to the above estimation of the conventional in-furnace condition. There was a problem that it was difficult to grasp the situation.

本発明は、炉内の銑滓レベルの不均一化や湯流れの不均一化の発生を迅速に検出すると共に、銑滓レベル及び炉内湯流れ状況を均一化する方法を提供することを目的とする。   It is an object of the present invention to provide a method for quickly detecting the occurrence of non-uniformity of the soot level in the furnace and the non-uniformity of the hot water flow, and to uniformize the soot level and the state of the hot water flow in the furnace. To do.

高炉炉内の銑滓レベルと関連があるとされている高炉鉄皮表面の炉底部高さ方向の電位差検出を行うと、出銑タイミング毎に電位差が変動し、出銑開始直前の銑滓レベルが最も高くなっているときに電位差は最も高い値を示し、出銑終了直前の銑滓レベルが最も低くなっているときに電位差は最も低い値を示す。ここでは、出銑タイミング毎に測定された最大電位差と最小電位差の差をΔＥとする。さらに、高炉円周方向複数個所において同時に電位差検出を行ったところ、炉内に局部的に不活性部位が形成されて湯流れが不均一化した場合において、円周方向測定位置毎のΔＥの値に較差が生じることが明らかになった。即ち、不活性部位が形成された近傍で測定した電位差のΔＥは、不活性部位が形成されていない近傍で測定した電位差のΔＥに比較して小さな値となる。このように炉体の測定部位によって生じるΔＥの差を、ここではΔＥの較差とよぶ。   When the potential difference in the furnace bottom height direction on the surface of the blast furnace core, which is considered to be related to the soot level in the blast furnace furnace, is detected, the potential difference fluctuates at each tapping timing, and the soot level immediately before the start of tapping The potential difference shows the highest value when is the highest, and the potential difference shows the lowest value when the heel level just before the end of output is the lowest. Here, ΔE is the difference between the maximum potential difference and the minimum potential difference measured at each output timing. Furthermore, when potential difference detection was performed simultaneously at a plurality of locations in the blast furnace circumferential direction, a value of ΔE at each circumferential measurement position was obtained when an inactive site was locally formed in the furnace and the molten metal flow became uneven. It became clear that there was a difference in. That is, the potential difference ΔE measured in the vicinity where the inactive site is formed is smaller than the potential difference ΔE measured in the vicinity where the inactive site is not formed. The difference in ΔE caused by the measurement site of the furnace body is referred to herein as a difference in ΔE.

高炉炉体内部の炉底レンガに複数個の電位測定点を高さ方向に間隔を開けて設け、電位測定点の間の電位差を測定すると、５ｍＶ前後の電位差が存在し、かつ出銑タイミング毎に測定された最大電位差と最小電位差の差ΔＥも５ｍＶ前後の大きな値となることが明らかになった。従来知られている高炉炉体の鉄皮表面で検出される電位差と比較すると、電位差の値および銑滓レベルの変動に伴う電位差の変動量ΔＥともに、１桁程度高い値である。そのため、ノイズの影響による誤差が非常に小さくなり、従来知られているいずれの方法と比較しても高い精度で銑滓レベルを推定することが可能になった。   A plurality of potential measurement points are provided on the bottom brick inside the blast furnace body at intervals in the height direction, and when the potential difference between the potential measurement points is measured, there is a potential difference of around 5 mV, and at each output timing. It was revealed that the difference ΔE between the maximum potential difference and the minimum potential difference measured in (1) was a large value around 5 mV. Compared to the conventionally known potential difference detected on the surface of the blast furnace core, both the value of the potential difference and the amount of potential difference variation ΔE associated with the variation of the soot level are higher by about one digit. For this reason, the error due to the influence of noise becomes very small, and it becomes possible to estimate the eyelid level with high accuracy compared to any conventionally known method.

本発明は上記知見に基づいてなされたものであり、その要旨とするところは以下のとおりである。
（１）高炉鉄皮１表面に複数個の電位測定点１１を高さ方向に間隔を開けて設け、電位測定点１１の間で電位差を測定する電位差測定装置１２とし、高炉炉体円周方向複数の個所に電位差測定装置１２を設け、各電位差測定装置１２において各出銑タイミング毎に最大電位差と最小電位差との差ΔＥを求め、各電位差測定装置毎のΔＥの較差に応じて該ΔＥ較差を是正するための高炉操業アクションを行うことを特徴とする高炉内銑滓レベル均一化方法。
（２）前記ΔＥ較差を是正するための高炉操業アクションは、ΔＥが小さい電位差測定装置付近の出銑口の使用を開始する又は当該出銑口からの出銑量を増大させるアクションであることを特徴とする上記（１）に記載の高炉内銑滓レベル均一化方法。
（３）高炉鉄皮表面に代え、高炉炉底レンガ５に複数個の電位測定点１１を設けることを特徴とする上記（１）又は（２）に記載の高炉内銑滓レベル均一化方法。
（４）前記複数の電位測定点１１の高炉高さ方向配置位置は、少なくとも１個所は出銑口レベル以上とし、他の電位測定点のうち少なくとも１個は出銑口レベル未満とすることを特徴とする上記（１）乃至（３）のいずれかに記載の高炉内銑滓レベル均一化方法。 This invention is made | formed based on the said knowledge, The place made into the summary is as follows.
(1) A plurality of potential measurement points 11 are provided on the surface of the blast furnace core 1 at intervals in the height direction, and a potential difference measurement device 12 that measures a potential difference between the potential measurement points 11 is used. A potential difference measuring device 12 is provided at a plurality of locations, and each potential difference measuring device 12 obtains a difference ΔE between the maximum potential difference and the minimum potential difference at each output timing, and the ΔE difference according to the difference of ΔE for each potential difference measuring device. A blast furnace leveling method characterized by performing blast furnace operation action to correct the blast furnace.
(2) The blast furnace operation action for correcting the ΔE range is an action for starting the use of the tap hole near the potential difference measuring device having a small ΔE or increasing the tap amount from the tap hole. The method for equalizing the level in a blast furnace furnace as described in (1) above.
(3) The blast furnace inner leveling method according to (1) or (2) above, wherein a plurality of potential measurement points 11 are provided on the blast furnace bottom brick 5 in place of the blast furnace iron surface.
(4) At least one location of the plurality of potential measurement points 11 in the blast furnace height direction is set to a level higher than the tap hole level, and at least one of the other potential measurement points is set to a level lower than the tap port level. The method for leveling a blast furnace soot level according to any one of (1) to (3) above,

本発明は、高炉炉体円周方向複数の高さ方向電位差を測定し、各出銑タイミング毎に最大電位差と最小電位差との差ΔＥを求め、各電位差測定装置毎のΔＥの較差に応じて該ΔＥ較差を是正するための高炉操業アクションを行うことにより、炉内の不活性部位発生をいち早くキャッチして高炉内の銑滓レベルを均一化することができ、出銑口毎の出銑量や出銑品質のばらつきを解消し、溶銑品質、炉体保護、操業安定性を維持することを可能にした。   The present invention measures a plurality of height direction potential differences in the circumferential direction of the blast furnace body, obtains a difference ΔE between the maximum potential difference and the minimum potential difference at each output timing, and according to the difference of ΔE for each potential difference measuring device. By performing the blast furnace operation action to correct the ΔE range, it is possible to quickly catch the generation of inactive parts in the furnace and make the blast furnace level uniform. In addition, it has been possible to eliminate variations in iron and steel quality and maintain hot metal quality, furnace protection, and operational stability.

本発明はさらに、電位測定点を炉底レンガに設けることにより、銑滓レベルの測定精度を一層向上させることができた。   Furthermore, the present invention can further improve the measurement accuracy of the soot level by providing potential measurement points on the brick at the bottom of the furnace.

本発明の上記（１）においては、図１に示すように、高炉鉄皮１表面に複数個の電位測定点１１を高さ方向に間隔を開けて設ける。銑滓レベルを評価するために有効な電位差は、高炉の高さ方向に発生しているからである。電位差を測定するのであるから個数は最低でも２個必要であり、高さ方向３個所以上にわたって３個以上の電位測定点１１を設ければ、高炉高さ方向の電位分布を評価に加えることも可能である。高さ方向複数の電位測定点の間で電位差を測定するので、この複数の電位測定点１１のセットを電位差測定装置１２と称する。   In the above (1) of the present invention, as shown in FIG. 1, a plurality of potential measurement points 11 are provided on the surface of the blast furnace iron shell 1 at intervals in the height direction. This is because the potential difference effective for evaluating the soot level is generated in the height direction of the blast furnace. Since the potential difference is measured, at least two pieces are required. If three or more potential measurement points 11 are provided in three or more height directions, the potential distribution in the blast furnace height direction can be added to the evaluation. Is possible. Since a potential difference is measured between a plurality of potential measurement points in the height direction, the set of the plurality of potential measurement points 11 is referred to as a potential difference measuring device 12.

複数の電位測定点１１の高さ方向取り付け位置は、溶銑と溶滓の境界面を挟むように配置すると、電位差測定値から銑滓レベルを評価するためには好ましい結果を得ることができる。具体的には、本発明の上記（４）にあるように、少なくとも１個の取り付け位置を出銑口３のレベル以上とし、少なくとも１個の取り付け位置を出銑口３のレベル未満とするように配置すれば、銑滓レベル評価のための電位差測定を行う上で好ましい。図１において、電位測定点１１ａは出銑口３のレベル未満に配置され、電位測定点１１ｂは出銑口３のレベル以上であって羽口４の位置に配置されている。羽口４のレベルを明らかにするため、図１（ｂ）に羽口４を部分図にて示している。   When the height direction attachment positions of the plurality of potential measurement points 11 are arranged so as to sandwich the interface between the hot metal and the hot metal, a preferable result can be obtained in order to evaluate the hot metal level from the potential difference measurement value. Specifically, as described in the above (4) of the present invention, at least one attachment position is set to be equal to or higher than the level of the spout opening 3, and at least one attachment position is set to be lower than the level of the spout opening 3. If it arrange | positions, it is preferable when measuring the electrical potential difference for wrinkle level evaluation. In FIG. 1, the potential measurement point 11 a is disposed below the level of the tap hole 3, and the potential measurement point 11 b is disposed at the position of the tuyere 4 above the level of the tap hole 3. In order to clarify the level of the tuyere 4, the tuyere 4 is shown in a partial view in FIG.

高炉円周方向の電位差測定装置１２の配置位置としては、図２に示す高炉炉体の円周方向４個所に、９０°ピッチで上記電位差測定装置１２を配置することができる。そのうちの２個所の電位差測定装置（１２ａ、１２ｂ）はそれぞれ出銑口（３ａ、３ｂ）の近辺に、残り２個所の電位差測定装置（１２ｃ、１２ｄ）は出銑口３と直角の位置に配置している。各電位差測定装置１２の電位測定点１１の高さ方向の配置については、図１に示すとおり、１個所は高炉炉底部、１個所は羽口レベルに配置するとよい。   As the arrangement position of the potential difference measuring device 12 in the blast furnace circumferential direction, the potential difference measuring device 12 can be arranged at a 90 ° pitch at four locations in the circumferential direction of the blast furnace body shown in FIG. Two of the potential difference measuring devices (12a, 12b) are arranged in the vicinity of the spout (3a, 3b), and the other two potential difference measuring devices (12c, 12d) are disposed at a right angle to the spout 3. doing. About the arrangement | positioning of the height direction of the electric potential measurement point 11 of each electric potential difference measuring device 12, as shown in FIG. 1, it is good to arrange | position one place to a blast furnace bottom part and one place to a tuyere level.

図２の配置位置とは若干異なるが、図３（ａ）に示す４つの出銑口（３ａ〜３ｄ）を有する高炉において、各出銑口の位置に電位差測定装置（１２ａ〜１２ｄ）を配置した。そのうち出銑口３ａと出銑口３ｂとを交互に開いて出銑を行っていることから、電位差測定装置１２ａ、及び１２ｂを選択し、電位差の測定結果の時間推移と出銑タイミングとの関係について評価した。   Although slightly different from the arrangement position of FIG. 2, in the blast furnace having four outlets (3a to 3d) shown in FIG. 3 (a), the potential difference measuring devices (12a to 12d) are arranged at the positions of the outlets. did. Among them, since the taps 3a and 3b are alternately opened and the tap is performed, the potential difference measuring devices 12a and 12b are selected, and the relationship between the time transition of the potential difference measurement results and the tap timing Was evaluated.

出銑口３ａ、３ｂからの出銑量や出銑温度に差異が存在せず、炉内に不活性部位が発生していないと推定される時期における電位差測定結果を、図３（ｂ）に示す。出銑口３ａからの出銑タイミング１７ａ及び引き続く出銑口３ｂからの出銑タイミング１７ｂにおいて、電位差測定装置１２ａで測定した測定電位差１５ａ及び電位差測定装置１２ｂで測定した測定電位差１５ｂの時間経過をプロットした。測定電位差１５は各出銑タイミング１７の出銑開始時に最も高い値を示し、出銑終了時に最も低い値を示すと同時に、測定電位差１５の最高値と最低値との差ΔＥについては、電位差測定装置１２ａ、電位差測定装置１２ｂのいずれの測定結果もほぼ同等の値を示しており、ΔＥの較差がほとんど存在しない。   FIG. 3 (b) shows the potential difference measurement results at the time when it is estimated that there is no difference in the amount and temperature of the taps from the taps 3a and 3b and no inactive sites are generated in the furnace. Show. The time course of the measured potential difference 15a measured by the potential difference measuring device 12a and the time difference of the measured potential difference 15b measured by the potential difference measuring device 12b at the output timing 17a from the output port 3a and the subsequent output timing 17b from the output port 3b are plotted. did. The measurement potential difference 15 shows the highest value at the start of output at each output timing 17 and shows the lowest value at the end of output. At the same time, the difference ΔE between the maximum value and the minimum value of the measurement potential difference 15 is measured by the potential difference. The measurement results of both the device 12a and the potential difference measuring device 12b show almost the same value, and there is almost no difference in ΔE.

一方、図４（ａ）に示すように出銑口３ｂの側に幅広く不活性部位１８が発生した場合において電位差の測定を行った。不活性部位１８の発生は、近傍の側壁レンガ温度が同レベルの他部位に比較して低くなっていることによって確認することができた。このときに電位差測定装置（１２ａ、１２ｂ）によって測定した電位差を図４（ｂ）に示す。高炉炉内が健全であった図３（ｂ）の結果と比較すると、出銑口３ａの近傍であって不活性部位１８から遠い電位差測定装置１２ａでは測定電位差１５ａの差ΔＥａが大きくなり、逆に不活性部位１８に近い電位差測定装置１２ｂでは測定電位差１５ｂの差ΔＥｂが小さくなっており、ΔＥの較差が大きくなっていることが明らかである。   On the other hand, as shown in FIG. 4A, the potential difference was measured when the inactive site 18 was widely generated on the side of the tap mouth 3b. Generation | occurrence | production of the inert site | part 18 was able to be confirmed by the side wall brick temperature of the vicinity being low compared with the other site | part of the same level. FIG. 4B shows the potential difference measured by the potential difference measuring device (12a, 12b) at this time. Compared with the result of FIG. 3B in which the inside of the blast furnace was sound, the difference ΔEa of the measured potential difference 15a is larger in the potential difference measuring device 12a in the vicinity of the taphole 3a and far from the inert portion 18, and vice versa. In the potential difference measuring device 12b close to the inert site 18, the difference ΔEb in the measured potential difference 15b is small, and it is clear that the difference in ΔE is large.

以上のとおり、炉内に局部的に不活性部位１８が形成されて湯流れが不均一化した場合において、円周方向測定位置毎のΔＥの値に較差が生じることが明らかになった。従って、本発明の上記（１）にあるように各電位差測定装置毎のΔＥの較差に応じて該ΔＥ較差を是正するための高炉操業アクションを行うこととすれば、不活性部位１８の発生をいち早くキャッチし、高炉の炉況が著しく悪化する前に不活性部位を解消することが可能になる。例えば、ΔＥの較差に予め所定の閾値を定めておき、測定したΔＥの較差がこの閾値を超えたときにΔＥが小さい電位差測定装置付近を不活性部位発生個所と認定する方法を採用することができる。   As described above, it has been clarified that when the inert portion 18 is locally formed in the furnace and the molten metal flow becomes non-uniform, there is a difference in the value of ΔE at each circumferential measurement position. Therefore, if the blast furnace operation action for correcting the ΔE difference is performed according to the difference of ΔE for each potential difference measuring device as described in (1) of the present invention, the generation of the inactive site 18 is prevented. It is possible to catch quickly and eliminate the inactive site before the blast furnace conditions deteriorate significantly. For example, a method may be adopted in which a predetermined threshold is set in advance for the difference in ΔE, and when the measured difference in ΔE exceeds this threshold, the vicinity of the potentiometric device having a small ΔE is recognized as an inactive site generation site. it can.

ΔＥに較差が生じたときにΔＥ較差を是正するための高炉操業アクションとしては、本発明の上記（２）にあるように、ΔＥが小さい電位差測定装置１２付近の出銑口３の使用を開始する又は当該出銑口３からの出銑量を増大させるアクションを採用することができる。   As the blast furnace operation action for correcting the ΔE difference when a difference occurs in ΔE, the use of the tap 3 near the potential difference measuring device 12 having a small ΔE is started as described in (2) of the present invention. Or an action for increasing the amount of tapping from the tapping port 3 can be adopted.

ΔＥが小さい電位差測定装置１２付近の出銑口３が使用されていない状態であれば、当該出銑口３の使用を開始することができる。ΔＥが小さい電位差測定装置１２付近の出銑口３が既に使用中であれば、当該出銑口３からの出銑量を増大させるアクションをとることができる。出銑口の径を大きな錐で掘削して拡大する促進開口を行うことにより、出銑口３からの出銑量を増大することができる。このようなアクションをとると、出銑量を増大した出銑口の近傍において、溶銑顕熱の伝熱による温度上昇により、湯流れを阻害していた未溶解物が溶解し、通液性が改善され、湯流れ領域の拡大、湯溜り領域の広域化という状況が形成され、結果として当該出銑量を増大した出銑口の近傍に形成されていた不活性部位を解消することが可能になる。   If the tap 3 near the potential difference measuring device 12 having a small ΔE is not used, the use of the tap 3 can be started. If the tap 3 near the potential difference measuring device 12 having a small ΔE is already in use, an action for increasing the tap output from the tap 3 can be taken. By carrying out the opening for digging and expanding the diameter of the taphole with a large cone, the amount of tapping from the taphole 3 can be increased. If such an action is taken, the undissolved material that hindered the hot water flow is dissolved by the temperature rise due to the heat transfer of the hot metal sensible heat in the vicinity of the spout opening where the amount of spout is increased, and the liquid permeability is improved. It is improved, and the situation of expansion of the hot water flow area and widening of the hot water pool area is formed, and as a result, it is possible to eliminate the inactive site formed in the vicinity of the tap outlet that increased the amount of the tap pouring Become.

上記２種類のアクションについては、それぞれ単独で実施して効果を上げることができるとともに、２つのアクションを同時に行えばより迅速に効果を発揮することが可能になる。   The above two types of actions can be carried out independently to increase the effect, and if the two actions are performed simultaneously, the effect can be exhibited more quickly.

高炉の炉底付近の内部構造は、図５に示すように、鉄皮１の内側に炉底レンガ５が築造され、炉底レンガ５の最外周と鉄皮１との間にはステーブ６が設けられたりあるいはスタンプ材７が充填されている。本発明の上記（３）においては、電位測定点の設置位置を、本発明（１）における高炉鉄皮表面に代えて炉底レンガ５に設ける。高炉炉体内部に位置する炉底レンガにおける電位測定点１１を用いて電位を測定するために、電位測定点１１から高炉炉体外部まで延びる電極１０を設ける。鉄皮１やステーブ６、スタンプ材７にはこの電極１０を通すための開口が設けられる。電極１０は電位測定点１１において炉底レンガ５に接触し、鉄皮１、ステーブ６、スタンプ材７などとの間に導通を生じないように外部に導かれ、高炉炉体外部において電極１０に別の導線１４を接続し、電圧計１３を用いて複数の電位測定点１１の間の電位差を測定する。   As shown in FIG. 5, the inner structure of the blast furnace near the bottom of the blast furnace is constructed such that a bottom brick 5 is built inside the iron shell 1, and a stave 6 is provided between the outermost periphery of the bottom brick 5 and the iron core 1. It is provided or is filled with a stamp material 7. In the above (3) of the present invention, the installation position of the potential measurement point is provided on the furnace bottom brick 5 in place of the surface of the blast furnace iron shell in the present invention (1). In order to measure the potential using the potential measurement point 11 in the bottom brick located inside the blast furnace body, an electrode 10 extending from the potential measurement point 11 to the outside of the blast furnace body is provided. The iron skin 1, the stave 6, and the stamp material 7 are provided with openings for passing the electrodes 10. The electrode 10 comes into contact with the furnace bottom brick 5 at the potential measurement point 11 and is guided to the outside so as not to cause conduction with the iron shell 1, the stave 6, the stamp material 7, and the like, and is connected to the electrode 10 outside the blast furnace body. Another conductor 14 is connected, and a potential difference between the plurality of potential measurement points 11 is measured using a voltmeter 13.

高炉炉体内部の炉底レンガ５に設けた電位測定点１１の間の電位差を測定すると、５ｍＶ前後の電位差が存在し、かつ高炉炉内の銑滓レベルの変動に伴う電位差の変動量ΔＥが５ｍＶ前後の値を示す。従来知られている高炉炉体の鉄皮表面で検出される電位差と比較すると、電位差の値および銑滓レベルの変動に伴う電位差の変動量ΔＥともに、１桁程度高い値である。そのため、ノイズの影響による誤差が非常に小さくなり、従来知られているいずれの方法と比較しても高い精度で銑滓レベルを推定することが可能になった。   When the potential difference between the potential measurement points 11 provided on the bottom brick 5 inside the blast furnace body is measured, there is a potential difference of about 5 mV, and the variation amount ΔE of the potential difference accompanying the variation of the soot level in the blast furnace furnace is The value is around 5 mV. Compared to the conventionally known potential difference detected on the surface of the blast furnace core, both the value of the potential difference and the amount of potential difference variation ΔE associated with the variation of the soot level are higher by about one digit. For this reason, the error due to the influence of noise becomes very small, and it becomes possible to estimate the eyelid level with high accuracy compared to any conventionally known method.

炉底レンガ５における高炉半径方向の電位測定点１１の配置位置は、図６（ａ）に示すように最も外周側である炉底レンガ表面に設けても良いし、図６（ｂ）に示すように炉底レンガ５に非貫通孔２０を設けた上で当該非貫通孔２０の奥端を電位測定点１１とする、すなわち炉底レンガ５の内部に電位測定点を設けても良い。   The arrangement position of the potential measuring point 11 in the blast furnace radial direction in the furnace bottom brick 5 may be provided on the surface of the furnace bottom brick which is the outermost side as shown in FIG. 6A, or as shown in FIG. Thus, after providing the non-through hole 20 in the furnace bottom brick 5, the back end of the non-through hole 20 may be set as the potential measurement point 11, that is, the potential measurement point may be provided inside the furnace bottom brick 5.

本発明（３）においても、電位測定点の高炉高さ方向の配置位置、および高炉円周方向の配置位置についての考え方は、本発明（１）と同様である。   In the present invention (3), the concept of the arrangement position of the potential measurement point in the blast furnace height direction and the arrangement position in the blast furnace circumferential direction are the same as in the present invention (1).

高炉炉体円周方向における出銑口の配置位置は、高炉毎に異なっている。図２に示すように円周方向１８０°の位置に２個所配置したもの、あるいは図３に示すように円周方向９０°毎の位置に４個所配置したものなどが稼働している。図３に示す配置の場合には、４個所すべての出銑口を常時用いることはせず、例えば出銑口３ａと出銑口３ｂの２個所を交互に開口して出銑を行う場合においては、出銑口３ｃと出銑口３ｄについては休止して樋の補修などを行うことが多い。このように休止した出銑口を有する高炉においては、休止した出銑口の近傍はその休止時間に比例して炉内が不活性になる傾向がある。従って、本発明の高炉内銑滓レベル均一化方法は、休止した出銑口を有する高炉において特に有効な効果を発揮することが可能である。   The arrangement position of the tap hole in the circumferential direction of the blast furnace body is different for each blast furnace. As shown in FIG. 2, two are arranged at 180 ° in the circumferential direction, or four are arranged at every 90 ° in the circumferential direction as shown in FIG. In the case of the arrangement shown in FIG. 3, not all of the four outlets are used at all times. For example, when two outlets, the outlet 3a and the outlet 3b, are opened alternately, In many cases, the exit port 3c and the exit port 3d are stopped and repaired. In such a blast furnace having an outage port, the vicinity of the outage port tends to become inactive in proportion to the outage time. Therefore, the method for equalizing the level in the blast furnace of the present invention can exert particularly effective effects in a blast furnace having a suspended taphole.

炉内容積３２７３ｍ3、炉床径１２．０ｍ、図３のように円周方向に４個所の出銑口を有する高炉において、本発明の高炉内銑滓レベル均一化方法を適用した。電位測定点１１を高炉鉄皮１表面とし、高さ方向の配置位置は図１に示すとおりであり、下方の測定点はこの炉体の出銑口３から５ｍ下方の炉底カーボンレンガ１段目レベルとし、上方の測定点は出銑口３から３．８ｍ上方の羽口と同一レベルとし、この２点間で電位差を測定する１組の電位差測定装置１２とした。電位差測定装置１２の高炉円周方向の配置位置は、４箇所の出銑口部とした。これら４組のうち２組の電位差測定装置を用いて電位差を測定し、各出銑タイミング毎に最大電位差と最小電位差との差ΔＥを求め、さらに各電位差測定装置毎のΔＥの較差を求めた。ΔＥ較差の閾値を０．２８ｍＶとし、ΔＥ較差がこの閾値を超えた際においては、ΔＥが最も小さい値となった電位差測定装置１２の近傍に不活性部位が発生しているものと判定し、不活性部位を消滅して銑滓レベルを均一化するためのアクションを実施した。ΔＥ較差の閾値を０．２８ｍＶとした理由は、この閾値以下になると出銑滓のアンバランスが発生する傾向があるためである。 In the blast furnace having an inner volume of 3273 m 3 , a hearth diameter of 12.0 m, and four outlets in the circumferential direction as shown in FIG. 3, the blast furnace inner leveling method of the present invention was applied. The potential measurement point 11 is the surface of the blast furnace iron skin 1, the arrangement position in the height direction is as shown in FIG. 1, and the lower measurement point is one stage of the bottom carbon brick 5 m below the outlet 3 of the furnace body. The eye level was set at the same level as the tuyere 3.8 m above the spout 3, and a pair of potential difference measuring devices 12 for measuring the potential difference between the two points was obtained. Arrangement positions of the potential difference measuring device 12 in the circumferential direction of the blast furnace were four tap holes. The potential difference was measured using two of the four sets of potential difference measuring devices, the difference ΔE between the maximum potential difference and the minimum potential difference was determined for each output timing, and the difference of ΔE for each potential difference measuring device was determined. . The threshold value of ΔE difference is set to 0.28 mV, and when the ΔE difference exceeds this threshold value, it is determined that an inactive site is generated in the vicinity of the potentiometer 12 where ΔE is the smallest value. Actions were taken to eliminate inactive sites and make the wrinkle level uniform. The reason why the threshold value of the ΔE difference is set to 0.28 mV is that there is a tendency that the output imbalance occurs when the threshold value is less than or equal to this threshold value.

ΔＥ較差を是正するための高炉操業アクションとしては、当該出銑口の錐径拡大、使用時間の増加、あるいは使用頻度の増加を採用した。   As the blast furnace operation action for correcting the ΔE range, the cone diameter expansion, the use time increase, or the use frequency increase was adopted.

従来は、溶銑成分や溶銑温度、出滓率などの指標において出銑口間の格差が顕著になったときに不活性部位が発生していると認識し、燃料費を大幅に増加し、炉床部に多大な燃料を投入することにより、不活性部位を活性化させる操業（クリーニング操業）を行っていた。しかし、これでは不活性部位発生の認識が遅すぎ、また回復までに要する時間及び燃料の増加とそれに伴う大幅な減産という問題が生じていた。それに対し、本発明の高炉内銑滓レベル均一化方法を採用した結果、不活性部位を迅速に是正して高炉内銑滓レベルを均一化することができ、出銑口毎の溶銑品質（溶銑成分、溶銑温度）の差が生じることがなく、炉体保護、操業安定を図る上で大きな効果を発揮することができた。   Conventionally, it has been recognized that an inert site has been generated when the disparity between outlets becomes significant in indicators such as hot metal components, hot metal temperature, and output rate, and fuel costs have been greatly increased. An operation (cleaning operation) for activating the inactive site by putting a large amount of fuel into the floor was performed. However, in this case, the recognition of the generation of inactive sites is too late, and there has been a problem of increased time and fuel required for recovery, and a significant reduction in production. On the other hand, as a result of adopting the blast furnace iron level leveling method of the present invention, it is possible to quickly correct the inactive site and uniformize the blast furnace iron level, and to improve the hot metal quality (hot metal quality) for each outlet. There was no difference between the components and the hot metal temperature), and a great effect was achieved in protecting the furnace body and stabilizing the operation.

本発明の電位差測定状況を示す図であり、（ａ）は高炉部分断面図、（ｂ）は羽口部を示す部分断面図である。It is a figure which shows the electrical potential difference measurement condition of this invention, (a) is a blast furnace partial sectional view, (b) is a partial sectional view which shows a tuyere part. 本発明の電位差測定状況を示す高炉の平面断面図である。It is a plane sectional view of a blast furnace which shows the potential difference measurement situation of the present invention. 不活性部位が発生していないときの本発明の電位差測定状況と電位差測定結果を示す図であり、（ａ）は出銑口、電位差測定装置を示す高炉の平面断面図であり、（ｂ）は電位差測定結果である。It is a figure which shows the electric potential difference measurement condition and electric potential difference measurement result of this invention when an inactive site has not generate | occur | produced, (a) is a plane sectional view of the blast furnace which shows a taphole and an electric potential difference measuring apparatus, (b) Is a potential difference measurement result. 不活性部位が発生しているときの本発明の電位差測定状況と電位差測定結果を示す図であり、（ａ）は出銑口、電位差測定装置、不活性部位発生位置を示す高炉の平面断面図であり、（ｂ）は電位差測定結果である。It is a figure which shows the electric potential difference measurement condition and electric potential difference measurement result of this invention when the inactive site has generate | occur | produced, (a) is a plane sectional drawing of the blast furnace which shows a taphole, an electric potential difference measuring apparatus, and an inactive site generating position (B) shows the result of potential difference measurement. 炉底レンガで電位差を測定する本発明を示す図であり、（ａ）は高炉部分断面図、（ｂ）は部分拡大図である。It is a figure which shows this invention which measures an electrical potential difference with a furnace bottom brick, (a) is a blast furnace partial sectional drawing, (b) is a partial enlarged view. 炉底レンガにおける電位測定点を示す図であり、（ａ）は炉底レンガ表面を電位測定点とし、（ｂ）は炉底レンガ内部を電位測定点としたものである。It is a figure which shows the electric potential measurement point in a furnace bottom brick, (a) makes a furnace bottom brick surface the electric potential measurement point, (b) makes the electric furnace measurement brick the electric potential measurement point.

符号の説明Explanation of symbols

１ 鉄皮
２ 炉内構造物
３ 出銑口
４ 羽口
５ 炉底レンガ
６ ステーブ
７ スタンプ材
８ 溶銑
９ スラグ
１０ 電極
１１ 電位測定点
１２ 電位差測定装置
１３ 電圧計
１４ 導線
１５ 測定電位差
１７ 出銑タイミング
１８ 不活性部位
２０ 非貫通孔 DESCRIPTION OF SYMBOLS 1 Iron skin 2 Furnace structure 3 Outlet 4 Tail 5 Furnace bottom brick 6 Stave 7 Stamp material 8 Hot metal 9 Slag 10 Electrode 11 Potential measuring point 12 Potential difference measuring device 13 Voltmeter 14 Conductive wire 15 Measuring potential difference 17 Outing timing 18 Inactive site 20 Non-through hole

Claims (4)

高炉鉄皮表面に複数個の電位測定点を高さ方向に間隔を開けて設け、前記電位測定点の間で電位差を測定する電位差測定装置とし、高炉炉体円周方向複数の個所に電位差測定装置を設け、前記各電位差測定装置において各出銑タイミング毎に最大電位差と最小電位差との差ΔＥを求め、各電位差測定装置毎のΔＥの較差に応じて該ΔＥ較差を是正するための高炉操業アクションを行うことを特徴とする高炉内銑滓レベル均一化方法。   A plurality of potential measurement points are provided on the surface of the blast furnace iron at an interval in the height direction, and a potential difference measurement device that measures a potential difference between the potential measurement points is used. A potential difference measurement is performed at a plurality of locations in the blast furnace body circumferential direction. A blast furnace operation is provided to provide a difference ΔE between the maximum potential difference and the minimum potential difference at each output timing in each of the potential difference measuring devices, and to correct the ΔE difference according to the difference of ΔE for each potential difference measuring device. A method for equalizing the level in a blast furnace. 前記ΔＥ較差を是正するための高炉操業アクションは、ΔＥが小さい電位差測定装置付近の出銑口の使用を開始する又は当該出銑口からの出銑量を増大させるアクションであることを特徴とする請求項１に記載の高炉内銑滓レベル均一化方法。   The blast furnace operation action for correcting the ΔE range is an action of starting the use of the tap hole near the potential difference measuring device having a small ΔE or increasing the tap amount from the tap hole. The blast furnace inner leveling method according to claim 1. 高炉鉄皮表面に代え、高炉炉底レンガに複数個の電位測定点を設けることを特徴とする請求項１又は２に記載の高炉内銑滓レベル均一化方法。   3. A method for equalizing the level of a blast furnace slag according to claim 1 or 2, wherein a plurality of potential measurement points are provided on a blast furnace bottom brick instead of the blast furnace iron surface. 前記複数の電位測定点の高炉高さ方向配置位置は、少なくとも１個所は出銑口レベル以上とし、他の電位測定点のうち少なくとも１個は出銑口レベル未満とすることを特徴とする請求項１乃至３のいずれかに記載の高炉内銑滓レベル均一化方法。   At least one location of the plurality of potential measurement points in the blast furnace height direction is set to a level higher than the tap hole level, and at least one of the other potential measurement points is set to a level lower than the tap port level. Item 4. The method for equalizing the level in the blast furnace in any one of Items 1 to 3.
JP2004063451A 2004-03-08 2004-03-08 Method for leveling the level in the blast furnace Expired - Lifetime JP4313701B2 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010138437A (en) * 2008-12-10 2010-06-24 Jfe Steel Corp Method for measuring level of melt in vertical furnace and device therefor
CN104131126A (en) * 2014-08-07 2014-11-05 中冶南方工程技术有限公司 Blast furnace slag flow detection method based on fuzzy model
CN106319122A (en) * 2016-10-09 2017-01-11 上海大学 Method and device for measuring slag-iron liquid level information of hearth of blast furnace online

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010138437A (en) * 2008-12-10 2010-06-24 Jfe Steel Corp Method for measuring level of melt in vertical furnace and device therefor
CN104131126A (en) * 2014-08-07 2014-11-05 中冶南方工程技术有限公司 Blast furnace slag flow detection method based on fuzzy model
CN104131126B (en) * 2014-08-07 2016-06-29 中冶南方工程技术有限公司 Blast furnace cinder flow rate testing methods based on fuzzy model
CN106319122A (en) * 2016-10-09 2017-01-11 上海大学 Method and device for measuring slag-iron liquid level information of hearth of blast furnace online

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