JP2020094240A - Oxygen blast furnace system and operation method of oxygen blast furnace - Google Patents
Oxygen blast furnace system and operation method of oxygen blast furnace Download PDFInfo
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本発明は、酸素または酸素富化空気と、気体還元材および／または固体還元材とを羽口から高炉内に供給して操業する酸素高炉設備および当該酸素高炉設備を用いた酸素高炉の操業方法に関する。 The present invention relates to an oxygen blast furnace facility that operates by supplying oxygen or oxygen-enriched air and a gas reducing agent and/or a solid reducing agent into a blast furnace from tuyere, and an operating method of an oxygen blast furnace using the oxygen blast furnace facility. Regarding
酸素高炉は、羽口から酸素または酸素を５０体積％以上含む酸素富化空気と、還元材である微粉炭と、を吹き込むことで空気を予熱した熱風送風を行う通常高炉と比較して、高炉内部での鉄鉱石の還元に作用しない炉内の窒素ガス量を低減し、これにより、高炉の生産性の向上を実現している。しかしながら、酸素高炉では羽口から純酸素を吹き込んで炉内滞留コークスと反応させるので、羽口先温度が異常に高温になるという課題がある。このため、酸素高炉の操業では、羽口先温度である羽口先の燃焼領域の温度を通常高炉と同等の２０００℃以上２６００℃以下程度に制御する必要がある。 Oxygen blast furnace is a blast furnace compared to a normal blast furnace that blows oxygen or oxygen-enriched air containing 50% by volume or more of oxygen from tuyere and pulverized coal that is a reducing agent to blow hot air by preheating the air. By reducing the amount of nitrogen gas in the furnace that does not affect the reduction of iron ore inside, the productivity of the blast furnace is improved. However, in the oxygen blast furnace, pure oxygen is blown from the tuyere to react with the coke staying in the furnace, which causes a problem that the tuyere tip temperature becomes abnormally high. Therefore, in the operation of the oxygen blast furnace, it is necessary to control the temperature of the combustion region at the tuyere, which is the tuyere temperature, to about 2000° C. or more and 2600° C. or less, which is equivalent to that of the normal blast furnace.
特許文献１には、ＣＯ２を含む炉頂ガスを還流させて羽口から純酸素とともに吹き込むことで、羽口先温度を所定の温度範囲に制御する方法が開示されている。また、特許文献１には、羽口から常温の純酸素とともに冷却剤であるＨ２ＯまたはＣＯ２を炉内に吹込み、羽口先温度を所定の温度範囲に制御しながら、窒素を含まない高炉ガスを発生させる方法も開示されている。 Patent Document 1 discloses a method in which a furnace top gas containing CO 2 is refluxed and blown together with pure oxygen from a tuyere to control the tuyere tip temperature within a predetermined temperature range. Further, in Patent Document 1, H 2 O or CO 2 which is a coolant is blown into the furnace together with pure oxygen at room temperature from the tuyere to control the tuyere tip temperature within a predetermined temperature range, but does not contain nitrogen. A method of generating blast furnace gas is also disclosed.
特許文献２には、純酸素とともに羽口先温度を調整する重質油を羽口から吹き込む酸素高炉の操業方法が開示されている。また、特許文献３には、純酸素の一部に予熱酸素を用いることで、固体還元材である微粉炭の着火性の改善と羽口先温度の調整を両立する酸素高炉の操業方法が開示されている。 Patent Document 2 discloses a method for operating an oxygen blast furnace in which heavy oil for adjusting the tuyere temperature is blown from the tuyere together with pure oxygen. Further, Patent Document 3 discloses a method for operating an oxygen blast furnace that uses preheated oxygen as a part of pure oxygen to improve the ignitability of pulverized coal which is a solid reducing material and adjust the tuyere temperature. ing.
羽口先の温度が高温化するのは、酸素高炉に特有の問題であって、例えば、特許文献１では羽口から常温純酸素とともにＨ２ＯやＣＯ２を吹き込んだときの吸熱反応を利用して羽口先温度を低下させている。これは、燃焼（酸化）とは逆反応（還元）の吸熱反応を利用して、異常に高温化した羽口先温度を低温化するものである。また、一般的に行われている羽口からの微粉炭吹込みの場合も、高炉でのコークス使用量の低減効果だけでなく、固体還元材としての吸熱反応を利用し、かつ、常温の微粉炭が昇温することにより羽口先温度を低下させている。 The increase in the temperature of the tuyere is a problem peculiar to the oxygen blast furnace. For example, in Patent Document 1, the endothermic reaction when H 2 O and CO 2 are blown from the tuyere together with room temperature pure oxygen is used. To lower the tuyere temperature. This utilizes an endothermic reaction, which is a reaction (reduction) that is the reverse of combustion (oxidation), to lower the temperature of the tuyere tip, which has become abnormally high. In addition, in the case of pulverized coal injection from the tuyere, which is generally performed, not only the effect of reducing the amount of coke used in the blast furnace but also the endothermic reaction as a solid reducing agent is used, and fine powder at room temperature is used. The tuyere temperature is lowered by the temperature rise of the charcoal.
一方で、酸素高炉においても、通常高炉と同様に多くの操業トラブルが発生する可能性がある。例えば、炉頂ガス循環設備が停止した場合、冷却剤であるＨ２ＯやＣＯ２が吹込めなくなるので羽口先温度は上昇し、例えば、純酸素とコークスのみの反応では３０００℃以上にもなる。また、微粉炭吹込みにおいても、経路内において微粉炭詰りが発生した場合、微粉炭の冷却剤としての機能が低下するので羽口先温度は上昇する。酸素高炉は通常高炉よりも微粉炭の吹込み量が多いので羽口先温度への影響は特に大きくなる。 On the other hand, in the oxygen blast furnace, many operational troubles may occur as in the normal blast furnace. For example, when the furnace top gas circulation facility is stopped, H 2 O and CO 2 that are coolants cannot be blown in, so the tuyere temperature rises, and for example, in the reaction of pure oxygen and coke alone, it reaches 3000° C. or higher. .. Further, even when pulverized coal is injected, if the pulverized coal is clogged in the path, the function of the pulverized coal as a coolant is lowered, and the tuyere temperature is increased. Since the oxygen blast furnace has a larger amount of pulverized coal blown in than the normal blast furnace, the effect on the tuyere temperature is particularly large.
羽口先温度が上昇すると、ＳｉＯ２が還元されＳｉＯガスとなって高炉を上昇し、冷却されて再度ＳｉＯ２となるときに当該ＳｉＯ２が高炉内の原料同士を接着する。この接着により高炉内の原料の棚吊が発生しやすくなる。高炉内における原料の棚吊は、酸素高炉の操業を阻害する原因となる。また、羽口先温度が上昇すると、羽口への熱負荷も大きくなる。羽口への熱負荷は、羽口破損の原因となるので、羽口の寿命が短くなると共に、羽口交換作業による高炉操業のダウンタイムの増加に繋がり、生産性を悪化させる。 When tuyere temperature rises, becomes SiO gas SiO 2 is reduced by increasing the blast furnace, the SiO 2 to adhere the material to each other in the blast furnace when the SiO 2 again cooled. Due to this adhesion, hanging of raw materials in the blast furnace is likely to occur. The suspension of raw materials in the blast furnace becomes a cause of hindering the operation of the oxygen blast furnace. Further, when the tuyere tip temperature rises, the heat load on the tuyere also increases. The heat load on the tuyere causes damage to the tuyere, which shortens the life of the tuyere and leads to an increase in downtime of the blast furnace operation due to the tuyere replacement work, which deteriorates the productivity.
一方、羽口への酸素の供給を停止すれば、酸素とコークスとの反応は停止し羽口先温度は低下するが、羽口が閉塞する可能性が高くなる。羽口が閉塞する原因は、通常操業では羽口から酸素（気体）を炉内へ吹き込むことで、吹き込まれた気体がコークスを押しのけて羽口先に空間を形成しているが、酸素が吹き込まれなくなればコークスを押しのけられず、空間の形成が不可能になるからである。また、羽口先の空間が無くなると共に、羽口先温度も低下すると、スラグ固着などにより羽口が閉塞しやすい状態となる。羽口が閉塞すると再送風が困難となるので、酸素高炉では、冷却剤の供給が停止した場合に、羽口閉塞を回避しつつ羽口先温度を制御する設備や、当該設備を用いた酸素高炉の操業方法が求められていた。 On the other hand, if the supply of oxygen to the tuyere is stopped, the reaction between oxygen and coke is stopped and the tuyere tip temperature is lowered, but the tuyere is likely to be blocked. The cause of the tuyere blockage is that in normal operation oxygen (gas) is blown into the furnace from the tuyere, and the blown gas pushes away the coke and forms a space at the tip of the tuyere. If it disappears, the coke cannot be pushed away, and it becomes impossible to form a space. Further, when the space at the tip of the tuyere disappears and the temperature of the tip of the tuyere decreases, the tuyere tends to be blocked due to slag sticking or the like. If the tuyere is clogged, it will be difficult to re-send the air.Therefore, in the oxygen blast furnace, if the coolant supply is stopped, the equipment that controls the tuyere tip temperature while avoiding the tuyere closure and the oxygen blast furnace that uses the equipment. Was required.
本発明は、上述した課題を鑑みてなされたものであり、その目的は、冷却剤の供給が停止した場合でも羽口先温度の上昇を抑制しつつ羽口閉塞を回避できる、酸素高炉設備および酸素高炉の操業方法を提供することである。 The present invention has been made in view of the above-mentioned problems, and an object thereof is to avoid tuyere blockage while suppressing an increase in the tuyere tip temperature even when the supply of the coolant is stopped, an oxygen blast furnace facility and oxygen. It is to provide a method of operating a blast furnace.
このような課題を解決するための本発明の特徴は、以下の通りである。
（１）酸素と、気体還元材および／または固体還元材と、を羽口から高炉内に供給して操業する酸素高炉設備であって、空気の圧力を高める圧縮機と、前記圧縮機によって圧力が高められた高圧空気を貯蔵する空気貯蔵設備と、気体還元材および／または固体還元材の流量を測定する流量計と、前記空気貯蔵設備から前記羽口への前記高圧空気の供給を制御する制御装置と、を有する、酸素高炉設備。
（２）酸素と、気体還元材および／または固体還元材と、を羽口から高炉内に供給して操業する酸素高炉設備であって、窒素の圧力を高める圧縮機と、前記圧縮機によって圧力が高められた高圧窒素を貯蔵する窒素貯蔵設備と、気体還元材および／または固体還元材の流量を測定する流量計と、前記窒素貯蔵設備から前記羽口への前記高圧窒素の供給を制御する制御装置と、を有する、酸素高炉設備。
（３）（１）に記載の酸素高炉設備を用いた酸素高炉の操業方法であって、前記気体還元材および／または固体還元材の流量が予め定められた流量以下になった場合に前記制御装置は、前記空気貯蔵設備から前記羽口に前記高圧空気を供給する、酸素高炉の操業方法。
（４）（１）に記載の酸素高炉設備を用いた酸素高炉の操業方法であって、前記酸素は、酸素を５０体積％以上含む酸素富化空気であり、前記気体還元材および／または固体還元材の流量が予め定められた流量以下になった場合に前記制御装置は、前記空気貯蔵設備から前記羽口に前記高圧空気を供給して酸素を５０体積％未満含む酸素富化空気に希釈する、酸素高炉の操業方法。
（５）（２）に記載の酸素高炉設備を用いた酸素高炉の操業方法であって、前記気体還元材および／または固体還元材の流量が予め定められた流量以下になった場合に前記制御装置は、前記窒素貯蔵設備から前記羽口に前記高圧窒素を供給する、酸素高炉の操業方法。
The features of the present invention for solving such a problem are as follows.
(1) An oxygen blast furnace facility that operates by supplying oxygen and a gas reducing agent and/or a solid reducing agent from tuyere into a blast furnace, and a compressor for increasing the pressure of air, and a pressure by the compressor. Storage facility for storing high-pressure air having increased temperature, a flow meter for measuring the flow rate of a gas reducing agent and/or a solid reducing agent, and controlling the supply of the high-pressure air from the air storage facility to the tuyere An oxygen blast furnace facility having a control device.
(2) An oxygen blast furnace facility that operates by supplying oxygen and a gas reducing agent and/or a solid reducing agent into the blast furnace from tuyere, and a compressor for increasing the pressure of nitrogen, and a pressure by the compressor. Storage facility for storing high-pressure nitrogen having a high temperature, a flow meter for measuring the flow rate of a gas reducing agent and/or a solid reducing agent, and controlling the supply of the high-pressure nitrogen from the nitrogen storage facility to the tuyere An oxygen blast furnace facility having a control device.
(3) A method of operating an oxygen blast furnace using the oxygen blast furnace facility according to (1), wherein the control is performed when the flow rate of the gas reducing agent and/or the solid reducing agent becomes equal to or lower than a predetermined flow rate. The apparatus is a method for operating an oxygen blast furnace, wherein the high pressure air is supplied from the air storage facility to the tuyere.
(4) A method for operating an oxygen blast furnace using the oxygen blast furnace facility according to (1), wherein the oxygen is oxygen-enriched air containing 50% by volume or more of oxygen, and the gas reducing material and/or solid When the flow rate of the reducing material becomes equal to or lower than a predetermined flow rate, the control device supplies the high pressure air from the air storage facility to the tuyere to dilute it into oxygen-enriched air containing less than 50% by volume of oxygen. How to operate the oxygen blast furnace.
(5) A method of operating an oxygen blast furnace using the oxygen blast furnace facility according to (2), wherein the control is performed when the flow rate of the gas reducing agent and/or the solid reducing agent becomes equal to or lower than a predetermined flow rate. The apparatus is a method for operating an oxygen blast furnace, which supplies the high-pressure nitrogen to the tuyere from the nitrogen storage facility.
本発明の酸素高炉設備を用いることで、冷却剤の供給が停止した場合に羽口閉塞を回避しつつ羽口先温度の上昇を抑制できる。このように、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できるので、冷却剤の供給停止というトラブルが解消した後に酸素や冷却剤の供給を容易に再開でき、酸素高炉の安定操業への復帰が容易になる。 By using the oxygen blast furnace facility of the present invention, it is possible to prevent the tuyere tip temperature from increasing while avoiding the tuyere blockage when the supply of the coolant is stopped. In this way, it is possible to avoid the tuyere blockage while suppressing the rise in the tuyere temperature, so it is possible to easily restart the supply of oxygen and coolant after the trouble of the supply stop of the coolant is solved, and to achieve stable operation of the oxygen blast furnace. Will be easier to return to.
本発明の実施形態を通じて本発明を説明する。図１は、第１の実施形態に係る酸素高炉設備１０を示す模式図である。酸素高炉設備１０は、高炉１２と、酸素供給設備２０と、微粉炭供給設備４０と、空気供給設備５０とを有する。酸素高炉設備１０の高炉１２においても、従来の熱風高炉と同じように炉頂から鉄鉱石や焼結鉱とともにコークスが装入される。高炉１２の炉下部には羽口設備１４が設けられており、当該羽口設備１４から熱風に代えて常温の純酸素が高炉１２内に供給される。 The present invention will be described through embodiments of the present invention. FIG. 1 is a schematic diagram showing an oxygen blast furnace facility 10 according to the first embodiment. The oxygen blast furnace facility 10 includes a blast furnace 12, an oxygen supply facility 20, a pulverized coal supply facility 40, and an air supply facility 50. In the blast furnace 12 of the oxygen blast furnace facility 10, coke is also charged from the furnace top together with iron ore and sinter as in the case of the conventional hot blast furnace. Tuyere equipment 14 is provided in the lower part of the blast furnace 12, and pure oxygen at room temperature is supplied from the tuyere equipment 14 into the blast furnace 12 in place of hot air.
酸素供給設備２０は、常温の酸素を製造し、羽口設備１４に酸素を供給する設備である。酸素供給設備２０は、酸素製造装置２２と、酸素配管２４と、酸素圧縮機２６と、高圧酸素配管２８と、酸素貯蔵設備３０と、酸素供給配管３２とを有する。図１に示した例において、酸素製造装置２２は、深冷分離法によって酸素を製造する設備であり、純酸素を製造する。酸素配管２４は、酸素製造装置２２と酸素圧縮機２６とを接続する配管である。酸素圧縮機２６は、酸素製造装置２２によって製造された純酸素を圧縮する。本実施形態において、酸素圧縮機２６は、純酸素の圧力を０．５ＭＰａ以上に圧縮する。 The oxygen supply facility 20 is a facility that produces oxygen at room temperature and supplies the oxygen to the tuyere facility 14. The oxygen supply facility 20 includes an oxygen production device 22, an oxygen pipe 24, an oxygen compressor 26, a high pressure oxygen pipe 28, an oxygen storage facility 30, and an oxygen supply pipe 32. In the example shown in FIG. 1, the oxygen production apparatus 22 is equipment for producing oxygen by the cryogenic separation method, and produces pure oxygen. The oxygen pipe 24 is a pipe that connects the oxygen production device 22 and the oxygen compressor 26. The oxygen compressor 26 compresses the pure oxygen produced by the oxygen producing device 22. In the present embodiment, the oxygen compressor 26 compresses the pressure of pure oxygen to 0.5 MPa or more.
酸素貯蔵設備３０は、圧縮された純酸素を貯蔵する設備である。このように、圧縮された純酸素を貯蔵する酸素貯蔵設備３０を設けることによって、酸素圧縮機２６と羽口設備１４間における圧縮された酸素の貯蔵量を増やすことができる。このように、圧縮された酸素の貯蔵量を増やすことで、純酸素を高炉に吹き込むことによる圧力低下が抑制されるので安定して高炉１２内に純酸素を供給できる。また、酸素貯蔵設備３０を設けることで、酸素圧縮機２６の装置規模を小さくできる。 The oxygen storage facility 30 is a facility that stores compressed pure oxygen. As described above, by providing the oxygen storage facility 30 for storing the compressed pure oxygen, the amount of compressed oxygen stored between the oxygen compressor 26 and the tuyere facility 14 can be increased. In this way, by increasing the storage amount of compressed oxygen, the pressure drop caused by blowing pure oxygen into the blast furnace is suppressed, so that pure oxygen can be stably supplied into the blast furnace 12. Further, by providing the oxygen storage facility 30, the device scale of the oxygen compressor 26 can be reduced.
酸素供給配管３２は、酸素貯蔵設備３０と羽口設備１４とを接続する配管である。圧縮された純酸素は、酸素供給配管３２および羽口設備１４を経由して高炉１２内に供給される。 The oxygen supply pipe 32 is a pipe that connects the oxygen storage facility 30 and the tuyere facility 14. The compressed pure oxygen is supplied into the blast furnace 12 via the oxygen supply pipe 32 and the tuyere facility 14.
微粉炭供給設備４０は、羽口設備１４に微粉炭を供給する設備である。微粉炭供給設備４０は、微粉炭配管４２と微粉炭流量計４４とを有する。微粉炭を微粉炭配管４２に供給する設備は、一般的な熱風高炉に用いられている設備と同じ設備を用いてよい。本実施形態に係る微粉炭供給設備４０では、微粉炭配管４２に微粉炭流量計４４が設けられている。微粉炭流量計４４は、微粉炭配管４２を流れる微粉炭の流量を測定する。なお、微粉炭流量計４４として、超音波を用いた流量計、マイクロ波を用いた流量計または静電容量２電極方式の微粉炭流量計を用いてよい。なお、微粉炭は、固体還元材の一例であり、微粉炭に代えて、廃プラスチックを用いてもよい。 The pulverized coal supply equipment 40 is equipment for supplying pulverized coal to the tuyere equipment 14. The pulverized coal supply facility 40 includes a pulverized coal pipe 42 and a pulverized coal flow meter 44. As the equipment for supplying the pulverized coal to the pulverized coal piping 42, the same equipment as that used for a general hot air blast furnace may be used. In the pulverized coal supply equipment 40 according to the present embodiment, a pulverized coal flow meter 44 is provided in the pulverized coal pipe 42. The pulverized coal flow meter 44 measures the flow rate of the pulverized coal flowing through the pulverized coal pipe 42. As the pulverized coal flowmeter 44, a flowmeter using ultrasonic waves, a flowmeter using microwaves, or a pulverized coal flowmeter of a capacitance two-electrode type may be used. Pulverized coal is an example of a solid reducing material, and waste plastic may be used instead of pulverized coal.
空気供給設備５０は、微粉炭供給設備４０から羽口設備１４に供給される微粉炭の流量が予め定められた流量よりも少なくなった場合に、羽口設備１４に空気を供給する設備である。微粉炭の流量が予め定められた流量よりも少なくなった場合に空気供給設備５０から空気を供給することで羽口先温度の上昇を抑制できる。 The air supply facility 50 is a facility that supplies air to the tuyere facility 14 when the flow rate of the pulverized coal supplied from the pulverized coal supply facility 40 to the tuyere facility 14 becomes smaller than a predetermined flow rate. .. When the flow rate of the pulverized coal becomes smaller than the predetermined flow rate, the air is supplied from the air supply facility 50, so that the rise of the tuyere temperature can be suppressed.
空気供給設備５０は、空気圧縮機５２と、高圧空気配管５４と、空気貯蔵設備５６と、空気供給配管５８と、制御装置９０とを有する。空気圧縮機５２は、常温の空気の圧力を高めて高圧空気とする。本実施形態において、空気圧縮機５２は、空気の圧力を０．５ＭＰａ以上に圧縮させる。 The air supply facility 50 includes an air compressor 52, a high-pressure air pipe 54, an air storage facility 56, an air supply pipe 58, and a controller 90. The air compressor 52 raises the pressure of normal temperature air to high pressure air. In the present embodiment, the air compressor 52 compresses the pressure of air to 0.5 MPa or more.
高圧空気配管５４は、空気圧縮機５２と空気貯蔵設備５６とを接続する配管である。空気貯蔵設備５６は、圧力が高められた高圧空気を貯蔵する設備である。このように、高圧空気を貯蔵する空気貯蔵設備５６を設けることによって、空気圧縮機５２と羽口設備１４間における高圧空気の貯蔵量を増やすことができる。高圧空気の貯蔵量を増やすことで、空気を高炉に吹き込むことによる空気の圧力低下が小さくなるので、高炉１２内への空気の供給が安定する。 The high-pressure air pipe 54 is a pipe that connects the air compressor 52 and the air storage facility 56. The air storage facility 56 is a facility that stores high-pressure air whose pressure has been increased. In this way, by providing the air storage facility 56 that stores high-pressure air, the storage amount of high-pressure air between the air compressor 52 and the tuyere facility 14 can be increased. By increasing the storage amount of high-pressure air, the pressure drop of the air caused by blowing the air into the blast furnace becomes small, so that the supply of air into the blast furnace 12 is stabilized.
空気供給配管５８は、空気貯蔵設備５６と羽口設備１４とを接続する配管である。制御装置９０は、制御装置９０は、空気貯蔵設備５６と羽口設備１４とを接続する空気供給配管５８に設けられ、空気貯蔵設備５６から羽口設備１４への高圧空気の供給量を制御する。制御装置９０は、例えば、流量調整弁である。 The air supply pipe 58 is a pipe that connects the air storage facility 56 and the tuyere facility 14. The control device 90 is provided in the air supply pipe 58 that connects the air storage facility 56 and the tuyere facility 14, and controls the amount of high-pressure air supplied from the air storage facility 56 to the tuyere facility 14. .. The control device 90 is, for example, a flow rate adjusting valve.
酸素高炉設備１０では、羽口設備１４から純酸素と微粉炭とを高炉１２内に供給しながら酸素高炉の操業が実施される。微粉炭を高炉１２内に供給することで、コークス使用量削減の効果だけでなく、固体還元材としての吸熱反応を利用し、かつ、常温の微粉炭が昇温するのに必要な顕熱により、羽口先温度の過度な昇温を抑制することができる。しかしながら、何らかの不具合により微粉炭の供給量が少なくなると、羽口先温度の上昇が抑制できなくなり、羽口先温度が上昇する。羽口先温度を低下させるために純酸素の供給を停止すると、酸素の供給によって押しのけられていた羽口先のコークスが羽口側に移動し、羽口先の空間が無くなると共に、羽口先温度も低下してくると、スラグ固着などにより羽口が閉塞しやすい状態となる。羽口閉塞が発生すると、微粉炭の供給停止というトラブルが解消した後に、純酸素や微粉炭の供給を再開することが困難になる。 In the oxygen blast furnace facility 10, the oxygen blast furnace is operated while supplying pure oxygen and pulverized coal from the tuyere facility 14 into the blast furnace 12. By supplying pulverized coal into the blast furnace 12, not only the effect of reducing the amount of coke used but also the endothermic reaction as a solid reducing material is utilized, and the sensible heat necessary for raising the temperature of the pulverized coal at room temperature is obtained. It is possible to suppress an excessive rise in the tuyere temperature. However, if the supply amount of pulverized coal decreases due to some trouble, the rise in tuyere temperature cannot be suppressed, and the tuyere temperature rises. When the supply of pure oxygen is stopped in order to lower the tuyere temperature, the coke at the tuyere that was pushed away by the oxygen supply moves to the tuyere side, the space at the tuyere disappears, and the tuyere temperature also drops. When coming in, the tuyere tends to be blocked due to slag sticking or the like. When the tuyere blockage occurs, it becomes difficult to restart the supply of pure oxygen or pulverized coal after the trouble of stopping the supply of pulverized coal is resolved.
これに対し、本実施形態では、微粉炭配管４２に微粉炭流量計４４を設け、微粉炭の流量が予め定められた流量以下になった場合に、制御装置９０は、空気供給配管５８を通じて空気貯蔵設備５６から羽口設備１４に高圧空気を供給する。高圧空気を供給することで、羽口設備１４から供給される酸素濃度が低下するので、冷却剤として機能する微粉炭の供給量が少なくなったとしても羽口先温度の上昇は抑制される。また、羽口設備１４への酸素の供給は継続されるので、羽口先温度の温度が低下し過ぎて羽口閉塞が発生することも抑制される。このように、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できるので、微粉炭の供給停止というトラブルが解消した後に酸素や微粉炭の供給を再開することが容易になり、酸素高炉の安定操業への復帰が容易になる。 On the other hand, in the present embodiment, the pulverized coal flowmeter 44 is provided in the pulverized coal pipe 42, and when the flow rate of the pulverized coal becomes equal to or less than the predetermined flow rate, the control device 90 causes the air supply pipe 58 to generate air. High pressure air is supplied from the storage facility 56 to the tuyere facility 14. By supplying the high-pressure air, the oxygen concentration supplied from the tuyere equipment 14 decreases, so that the rise in the tuyere tip temperature is suppressed even if the supply amount of the pulverized coal that functions as a coolant decreases. Further, since the supply of oxygen to the tuyere equipment 14 is continued, it is also possible to prevent the tuyere tip temperature from being excessively lowered and causing the tuyere blockage. In this way, since it is possible to avoid the tuyere blockage while suppressing the rise in the tuyere temperature, it becomes easy to restart the supply of oxygen and pulverized coal after the trouble of the supply stop of pulverized coal is resolved, and the oxygen blast furnace It will be easy to return to stable operation.
羽口保護の観点から微粉炭の吹込みが停止した後、なるべく早く高圧空気を供給することが好ましいが、羽口設備１４からのガスの吹込み量が急激に増加させると、酸素高炉の操業が不安定になる。このため、高圧空気を供給とともに純酸素の供給量を減らして、羽口設備１４からのガスの吹込み量を一定にすることが好ましい。これにより、酸素高炉の操業を安定に維持できる。 From the viewpoint of tuyere protection, it is preferable to supply high-pressure air as soon as possible after the pulverized coal blowing is stopped, but if the gas blowing amount from the tuyere equipment 14 is rapidly increased, the operation of the oxygen blast furnace will be performed. Becomes unstable. For this reason, it is preferable to supply high-pressure air and reduce the supply amount of pure oxygen so that the amount of gas blown from the tuyere equipment 14 is constant. Thereby, the operation of the oxygen blast furnace can be stably maintained.
なお、図１に示した酸素高炉設備１０では微粉炭を冷却剤として用いる例を示したが、これに限らない。例えば、微粉炭に代えて、または、微粉炭とともに冷却剤として気体還元材を用いてもよい。気体還元材としては、例えば、都市ガス、プロパンガス、製鉄所内で発生する副生ガスを用いてよい。気体還元材を用いた場合においても、気体還元材を羽口設備１４に供給する配管に流量計を設け、気体還元材の流量が予め定められた流量以下になった場合に、制御装置９０は、空気貯蔵設備５６から羽口設備１４に高圧空気を供給する。これにより、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できる。 In the oxygen blast furnace facility 10 shown in FIG. 1, an example in which pulverized coal is used as the coolant is shown, but the invention is not limited to this. For example, a gas reducing agent may be used as a coolant instead of or together with pulverized coal. As the gas reducing material, for example, city gas, propane gas, or by-product gas generated in a steel mill may be used. Even in the case of using the gas reducing material, the control device 90 is provided with a flow meter provided in the pipe for supplying the gas reducing material to the tuyere facility 14, and when the flow rate of the gas reducing material becomes equal to or less than a predetermined flow rate. The air storage facility 56 supplies high pressure air to the tuyere facility 14. Thereby, the tuyere blockage can be avoided while suppressing the rise of the tuyere tip temperature.
また、図１に示した酸素高炉設備１０では酸素貯蔵設備３０を有する例を示したが、これに限られない。高圧酸素は、常時高炉１２内に供給されるので、酸素貯蔵設備３０を有さなくてもよい。一方、内部監視孔のガラス保護のために流される微量の空気を除く高圧空気は、微粉炭等の冷却剤の流量が予め定められた流量以下になった場合に限り高炉１２内に供給される。このように、高圧空気は常時供給されるものではないので、所定容量の高圧空気を貯蔵できる空気貯蔵設備５６を設けると、高圧空気が供給されない間に空気を圧縮させ、空気貯蔵設備５６に蓄えることができるので、空気圧縮機５２の装置規模を小さくできる。また、所定容量の空気貯蔵設備５６を設けることで、空気を高炉に吹き込むことによる空気の圧力低下が小さくなるので、安定して高炉１２内に空気を供給できる。なお、４０００ｍ３級の高炉１２を用いた場合において、空気貯蔵設備５６の容量は、２５００ｍ３以上５０００ｍ３以下にすることが好ましい。 Further, although the oxygen blast furnace facility 10 shown in FIG. 1 has an example in which the oxygen storage facility 30 is provided, the present invention is not limited to this. Since high-pressure oxygen is constantly supplied into the blast furnace 12, the oxygen storage facility 30 may not be provided. On the other hand, the high-pressure air excluding a small amount of air that is flown to protect the glass of the internal monitoring hole is supplied into the blast furnace 12 only when the flow rate of the coolant such as pulverized coal is equal to or lower than a predetermined flow rate. .. As described above, since high-pressure air is not always supplied, if an air storage facility 56 capable of storing a predetermined volume of high-pressure air is provided, the air is compressed while the high-pressure air is not supplied and stored in the air storage facility 56. Therefore, the device scale of the air compressor 52 can be reduced. Further, by providing the air storage facility 56 having a predetermined capacity, the pressure drop of the air caused by blowing the air into the blast furnace is reduced, so that the air can be stably supplied into the blast furnace 12. When the 4000 m 3 class blast furnace 12 is used, the capacity of the air storage facility 56 is preferably 2500 m 3 or more and 5000 m 3 or less.
図２は、第２の実施形態に係る酸素高炉設備１６を示す模式図である。酸素高炉設備１６は、高炉１２と、酸素供給設備２１と、微粉炭供給設備４０と、空気供給設備５１とを有する。酸素高炉設備１６では、当該羽口設備１４から酸素を５０体積％以上含む酸素富化空気が高炉１２内に供給される。なお、図２の酸素高炉設備１６において、図１に示した酸素高炉設備１０と同じ要素には同じ参照番号を付して重複する説明を省略する。酸素高炉設備１６は、酸素供給配管３４および空気供給配管５９を有する点において、図１に示した酸素高炉設備１０と異なる。 FIG. 2 is a schematic diagram showing an oxygen blast furnace facility 16 according to the second embodiment. The oxygen blast furnace facility 16 includes a blast furnace 12, an oxygen supply facility 21, a pulverized coal supply facility 40, and an air supply facility 51. In the oxygen blast furnace facility 16, oxygen-enriched air containing 50% by volume or more of oxygen is supplied from the tuyere facility 14 into the blast furnace 12. In the oxygen blast furnace equipment 16 of FIG. 2, the same elements as those of the oxygen blast furnace equipment 10 shown in FIG. The oxygen blast furnace facility 16 differs from the oxygen blast furnace facility 10 shown in FIG. 1 in that it has an oxygen supply pipe 34 and an air supply pipe 59.
酸素供給配管３４は、酸素貯蔵設備３０と空気供給配管５９とを接続する配管である。酸素貯蔵設備３０に貯蔵された高圧酸素は、酸素供給配管３４、空気供給配管５９および羽口設備１４を経由して高炉１２内に供給される。 The oxygen supply pipe 34 is a pipe that connects the oxygen storage facility 30 and the air supply pipe 59. The high-pressure oxygen stored in the oxygen storage facility 30 is supplied into the blast furnace 12 via the oxygen supply pipe 34, the air supply pipe 59, and the tuyere facility 14.
空気供給配管５９は、空気供給配管５８とは別に設けられた、空気貯蔵設備５６と羽口設備１４とを接続する配管である。空気供給配管５９を通じて空気貯蔵設備５６から所定量の高圧空気が供給され、純酸素は酸素を５０体積％以上含む酸素富化空気に希釈される。酸素を５０体積％以上含む酸素富化空気は、羽口設備１４から高炉１２内に供給される。 The air supply pipe 59 is a pipe that is provided separately from the air supply pipe 58 and that connects the air storage facility 56 and the tuyere facility 14. A predetermined amount of high-pressure air is supplied from the air storage facility 56 through the air supply pipe 59, and pure oxygen is diluted with oxygen-enriched air containing 50% by volume or more of oxygen. Oxygen-enriched air containing 50% by volume or more of oxygen is supplied from the tuyere facility 14 into the blast furnace 12.
このような、酸素高炉設備１６では、羽口設備１４から酸素を５０体積％以上含む酸素富化空気と微粉炭とを高炉１２内に供給しながら酸素高炉の操業が実施される。微粉炭を羽口設備１４から高炉１２内に供給することで、高炉１２でのコークス使用量削減の効果だけでなく、固体還元材の吸熱反応により羽口先温度の上昇が抑制される効果が得られる。しかしながら、何らかの不具合により微粉炭の供給量が少なくなると、羽口先温度を低温化できなくなるので酸素を５０体積％以上含む酸素富化空気であっても羽口先温度が上昇する。この対応として、酸素を５０体積％以上含む酸素富化空気の供給を停止すると、羽口先の空間がなくなるとともに羽口先温度が低下し過ぎて羽口が閉塞する。 In the oxygen blast furnace facility 16 as described above, the oxygen blast furnace is operated while supplying the oxygen-enriched air containing 50% by volume or more of oxygen and the pulverized coal from the tuyere facility 14 into the blast furnace 12. By supplying pulverized coal from the tuyere facility 14 into the blast furnace 12, not only the effect of reducing the amount of coke used in the blast furnace 12 but also the effect of suppressing the rise in the tuyere tip temperature due to the endothermic reaction of the solid reducing material are obtained. Be done. However, if the supply amount of pulverized coal decreases due to some trouble, the tuyere temperature cannot be lowered, and therefore the tuyere temperature rises even with oxygen-enriched air containing 50% by volume or more of oxygen. As a countermeasure against this, when the supply of oxygen-enriched air containing 50% by volume or more of oxygen is stopped, the space at the tuyere disappears and the tuyere temperature is excessively lowered to close the tuyere.
本実施形態では、微粉炭配管４２に微粉炭流量計４４を設け、微粉炭の流量が予め定められた流量以下になった場合に、制御装置９０は、空気供給配管５８を通じて、空気貯蔵設備５６から羽口設備１４に高圧空気を供給して酸素を５０体積％未満含む酸素富化空気に希釈する。これにより、羽口設備１４から供給される酸素負化空気の酸素濃度が低下するので、冷却剤として機能する微粉炭の供給量が少なくなったとしても羽口先温度の上昇は抑制される。また、羽口設備１４への酸素の供給は継続されるので羽口先の空間が確保され、また、羽口先温度の温度が低下し過ぎることが抑制され、これにより、羽口閉塞の発生が抑制される。このように、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できるので、微粉炭の供給停止というトラブルが解消した後に酸素や微粉炭の供給を再開することが容易になり、酸素高炉の安定操業への復帰が容易になる。 In the present embodiment, the pulverized coal flowmeter 44 is provided in the pulverized coal pipe 42, and when the flow rate of the pulverized coal becomes equal to or lower than a predetermined flow rate, the control device 90 causes the air storage facility 56 to flow through the air supply pipe 58. To supply the high pressure air to the tuyere equipment 14 to dilute the oxygen-enriched air containing less than 50% by volume of oxygen. As a result, the oxygen concentration of the oxygen-negative air supplied from the tuyere equipment 14 decreases, so that the rise in the tuyere tip temperature is suppressed even if the supply amount of the pulverized coal that functions as a coolant decreases. Further, since the supply of oxygen to the tuyere equipment 14 is continued, the space at the tuyere tip is secured, and the temperature of the tuyere tip temperature is prevented from being excessively lowered, thereby suppressing the occurrence of the tuyere blockage. To be done. In this way, since it is possible to avoid the tuyere blockage while suppressing the rise in the tuyere temperature, it becomes easy to restart the supply of oxygen and pulverized coal after the trouble of the supply stop of pulverized coal is resolved, and the oxygen blast furnace It will be easy to return to stable operation.
図３は、第３の実施形態に係る酸素高炉設備１８を示す模式図である。酸素高炉設備１８は、高炉１２と、酸素供給設備２０と、微粉炭供給設備４０と、窒素供給設備６０とを有する。酸素高炉設備１８では、当該羽口設備１４から熱風に代えて常温の純酸素が高炉１２内に供給される。なお、図３の酸素高炉設備１８において、図１に示した酸素高炉設備１０と同じ要素には同じ参照番号を付して重複する説明を省略する。酸素高炉設備１８は、窒素供給設備６０を有する点において、図１に示した酸素高炉設備１０と異なる。 FIG. 3 is a schematic diagram showing an oxygen blast furnace facility 18 according to the third embodiment. The oxygen blast furnace facility 18 includes a blast furnace 12, an oxygen supply facility 20, a pulverized coal supply facility 40, and a nitrogen supply facility 60. In the oxygen blast furnace facility 18, pure oxygen at room temperature is supplied from the tuyere facility 14 into the blast furnace 12 in place of hot air. In the oxygen blast furnace equipment 18 of FIG. 3, the same elements as those of the oxygen blast furnace equipment 10 shown in FIG. 1 are designated by the same reference numerals, and a duplicate description will be omitted. The oxygen blast furnace facility 18 differs from the oxygen blast furnace facility 10 shown in FIG. 1 in that it has a nitrogen supply facility 60.
窒素供給設備６０は、窒素圧縮機６２と、高圧窒素配管６４と、窒素貯蔵設備６６と、窒素供給配管６８と、制御装置９０とを有する。窒素圧縮機６２は、常温の窒素の圧力を高めて高圧窒素とする。なお、本実施形態において、窒素は、深冷分離法によって酸素を製造する酸素製造装置２２により製造される窒素を用いることができる。また、窒素圧縮機６２は、窒素の圧力を０．５ＭＰａ以上圧縮させる。 The nitrogen supply facility 60 includes a nitrogen compressor 62, a high-pressure nitrogen pipe 64, a nitrogen storage facility 66, a nitrogen supply pipe 68, and a controller 90. The nitrogen compressor 62 raises the pressure of nitrogen at room temperature into high pressure nitrogen. In addition, in this embodiment, as the nitrogen, nitrogen produced by the oxygen producing apparatus 22 that produces oxygen by the cryogenic separation method can be used. Further, the nitrogen compressor 62 compresses the pressure of nitrogen by 0.5 MPa or more.
高圧窒素配管６４は、窒素圧縮機６２と窒素貯蔵設備６６とを接続する配管である。窒素貯蔵設備６６は、圧力が高められた高圧窒素を貯蔵する設備である。このように、高圧窒素を貯蔵する窒素貯蔵設備６６を設けることによって、窒素圧縮機６２と羽口設備１４間における高圧窒素の貯蔵量を増やすことができる。高圧窒素の貯蔵量を増やすことで、窒素を高炉１２に吹き込むことによる窒素の圧力低下が小さくなるので、高炉１２内への窒素の供給が安定する。 The high-pressure nitrogen pipe 64 is a pipe that connects the nitrogen compressor 62 and the nitrogen storage facility 66. The nitrogen storage facility 66 is a facility for storing high-pressure nitrogen whose pressure has been increased. As described above, by providing the nitrogen storage facility 66 for storing high-pressure nitrogen, the storage amount of high-pressure nitrogen between the nitrogen compressor 62 and the tuyere facility 14 can be increased. By increasing the storage amount of high-pressure nitrogen, the pressure drop of nitrogen caused by blowing nitrogen into the blast furnace 12 becomes small, so that the supply of nitrogen into the blast furnace 12 is stabilized.
酸素高炉設備１８では、羽口設備１４から純酸素と微粉炭とを高炉１２内に供給しながら酸素高炉の操業が実施される。しかしながら、何らかの不具合により微粉炭の供給量が少なくなると、羽口先温度を低温化できなり、羽口先温度が上昇する。一方、羽口先温度を低下させるために純酸素の供給を停止すると、羽口先の空間がなくなるとともに羽口先温度が低下し過ぎて羽口が閉塞する。 In the oxygen blast furnace facility 18, the oxygen blast furnace is operated while supplying pure oxygen and pulverized coal from the tuyere facility 14 into the blast furnace 12. However, if the amount of pulverized coal supplied decreases due to some trouble, the tuyere temperature cannot be lowered, and the tuyere temperature rises. On the other hand, when the supply of pure oxygen is stopped in order to lower the tuyere temperature, the space at the tuyere is lost and the tuyere temperature is too low, and the tuyere is blocked.
本実施形態では、微粉炭配管４２に微粉炭流量計４４を設け、微粉炭の流量が予め定められた流量以下になった場合に、制御装置９０は、窒素供給配管６８を通じて窒素貯蔵設備６６から羽口設備１４に高圧窒素を供給する。高圧窒素を供給することで、羽口設備１４から供給される酸素濃度が低下するので、冷却剤として機能する微粉炭の供給量が少なくなったとしても羽口先温度の上昇は抑制される。また、羽口設備１４への酸素の供給は継続されるので羽口先の空間が確保され、また、羽口先温度の温度が低下し過ぎることが抑制され、これにより、羽口閉塞の発生が抑制される。このように、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できるので、微粉炭の供給停止というトラブルが解消した後に酸素や微粉炭の供給を再開することが容易になり、酸素高炉の安定操業への復帰が容易になる。 In the present embodiment, the pulverized coal flowmeter 44 is provided in the pulverized coal pipe 42, and when the flow rate of the pulverized coal becomes equal to or lower than a predetermined flow rate, the control device 90 causes the nitrogen storage facility 66 to operate from the nitrogen storage facility 66 through the nitrogen supply pipe 68. High-pressure nitrogen is supplied to the tuyere equipment 14. By supplying the high-pressure nitrogen, the oxygen concentration supplied from the tuyere equipment 14 is reduced, so that the rise in the tuyere temperature is suppressed even if the supply amount of the pulverized coal that functions as a coolant is reduced. Further, since the supply of oxygen to the tuyere equipment 14 is continued, the space at the tuyere tip is secured, and the temperature of the tuyere tip temperature is prevented from being excessively lowered, thereby suppressing the occurrence of the tuyere blockage. To be done. In this way, since it is possible to avoid the tuyere blockage while suppressing the rise in the tuyere temperature, it becomes easy to restart the supply of oxygen and pulverized coal after the trouble of the supply stop of pulverized coal is resolved, and the oxygen blast furnace It will be easy to return to stable operation.
図４は、羽口設備１４の断面模式図である。羽口設備１４は、羽口７０と、バーナー７２とを有する。バーナー７２は羽口７０に内包されるように接続されている。羽口設備１４が酸素高炉設備１０、１６に設けられる場合に、バーナー７２には外側から、酸素供給配管３２、微粉炭配管４２、空気供給配管５８の順に接続する。一方、羽口設備１４が酸素高炉設備１８に設けられる場合に、バーナー７２には外側から、酸素供給配管３２、微粉炭配管４２、窒素供給配管６８の順に接続する。なお、微粉炭とともに気体還元材を高炉１２内に供給する場合には、気体還元材配管７４は、酸素供給配管３２と微粉炭配管４２との間に接続する。 FIG. 4 is a schematic sectional view of the tuyere facility 14. The tuyere installation 14 includes a tuyere 70 and a burner 72. The burner 72 is connected so as to be included in the tuyere 70. When the tuyere equipment 14 is installed in the oxygen blast furnace equipment 10 and 16, the oxygen supply pipe 32, the pulverized coal pipe 42, and the air supply pipe 58 are sequentially connected to the burner 72 from the outside. On the other hand, when the tuyere facility 14 is provided in the oxygen blast furnace facility 18, the oxygen supply pipe 32, the pulverized coal pipe 42, and the nitrogen supply pipe 68 are sequentially connected to the burner 72 from the outside. When supplying the gas reducing material together with the pulverized coal into the blast furnace 12, the gas reducing material pipe 74 is connected between the oxygen supply pipe 32 and the pulverized coal pipe 42.
空気供給配管５８または窒素供給配管６８とバーナー７２との接続部には内部監視窓が設けられており、内部監視窓を保護する目的で、少量の高圧空気や高圧窒素を流している。このような羽口設備１４において、微粉炭の供給量が少なくなると羽口先温度が急激に上昇し、羽口７０の熱負荷が大きくなる。羽口７０の熱負荷が大きくなると、羽口破損の原因となり、羽口の寿命が短くなる。 An internal monitoring window is provided at the connection between the air supply pipe 58 or the nitrogen supply pipe 68 and the burner 72, and a small amount of high-pressure air or high-pressure nitrogen is supplied for the purpose of protecting the internal monitoring window. In such a tuyere installation 14, when the supply amount of pulverized coal decreases, the tuyere temperature rises rapidly and the heat load on the tuyere 70 increases. A large heat load on the tuyere 70 causes damage to the tuyere and shortens the life of the tuyere.
本実施形態に係る酸素高炉設備１０、１６、１８では、微粉炭の流量が予め定められた流量以下になった場合、空気または窒素を羽口設備１４に供給して羽口先温度の上昇を抑制している。これにより、羽口７０の熱負荷の増大を抑制でき、羽口寿命の低下を抑制できる。 In the oxygen blast furnace equipment 10, 16 and 18 according to the present embodiment, when the flow rate of pulverized coal becomes equal to or lower than a predetermined flow rate, air or nitrogen is supplied to the tuyere equipment 14 to suppress an increase in tuyere tip temperature. doing. As a result, an increase in the heat load on the tuyere 70 can be suppressed, and a decrease in the life of the tuyere can be suppressed.
（実施例１）
次に酸素高炉設備１０を用いた酸素高炉の操業方法の効果を、高炉の下部を模擬したラボ実験設備８０を用いて確認した実施例１を説明する。図５は、ラボ実験設備８０の断面模式図である。ラボ実験設備８０は、実験炉８４の炉壁８２に図４に示した羽口設備１４が設けられている。高炉１２の下部を模擬し、実験炉８４にコークスを充填した。実験炉８４に充填したコークスの粒径の範囲は６〜１５ｍｍである。
(Example 1)
Next, Example 1 in which the effect of the operation method of the oxygen blast furnace using the oxygen blast furnace equipment 10 was confirmed by using the laboratory experiment equipment 80 simulating the lower part of the blast furnace will be described. FIG. 5 is a schematic sectional view of the laboratory experiment equipment 80. The lab experimental equipment 80 is provided with the tuyere equipment 14 shown in FIG. 4 on the furnace wall 82 of the experimental furnace 84. The lower part of the blast furnace 12 was simulated, and the experimental furnace 84 was filled with coke. The particle size range of the coke charged in the experimental furnace 84 is 6 to 15 mm.
酸素供給配管３２から常温の純酸素４５Ｎｍ３／ｈと、微粉炭配管４２から溶銑１ｔ当たり３３０ｋｇに相当する量の微粉炭と、を羽口設備１４を通じて実験炉８４に吹込んでコークスを燃焼させた。なお、内部監視孔のガラスを保護するために、通常時においても少量の空気を流した。羽口先温度は、バーナー７２の中央部に設けられた内部監視孔の後方に設置された２色式放射温度計８６（株式会社チノー社製、ＩＲ−ＦＬ）を用いて測定した。 Pure oxygen at a normal temperature of 45 Nm 3 /h from the oxygen supply pipe 32 and pulverized coal in an amount corresponding to 330 kg per ton of molten pig iron from the pulverized coal pipe 42 were blown into the experimental furnace 84 through the tuyere facility 14 to burn coke. .. In addition, in order to protect the glass of the internal monitoring hole, a small amount of air was made to flow even in normal times. The tuyere temperature was measured using a two-color radiation thermometer 86 (IR-FL manufactured by Chino Co., Ltd.) installed behind an internal monitoring hole provided in the central portion of the burner 72.
図６は、羽口先温度の時間変化を示すグラフである。図６において、横軸は時間（秒）であり、縦軸は羽口先温度（℃）である。図６の（ア）の領域は、純酸素と微粉炭とを実験炉８４に吹込んだ場合の羽口先温度の時間変化を示す。（ア）の領域では、純酸素を吹込んでいるものの冷却剤としての微粉炭を吹込んでいるので、羽口先温度は１５００から２０００℃になった。 FIG. 6 is a graph showing the time variation of the tuyere tip temperature. In FIG. 6, the horizontal axis represents time (second) and the vertical axis represents tuyere temperature (° C.). The area (A) of FIG. 6 shows the time variation of the tuyere temperature when pure oxygen and pulverized coal are blown into the experimental furnace 84. In the region (a), since pure oxygen was blown, but pulverized coal as a coolant was blown, the tuyere temperature increased from 1500 to 2000°C.
図６（イ）の領域では、微粉炭詰りを再現するために微粉炭の吹込みを意図的に停止させ、純酸素のみを実験炉８４に吹込んだ。（イ）の領域では、冷却剤としての役割を担う微粉炭の吹込みが停止されたので、羽口先温度は上昇し、２０００℃を超える場合もあった。 In the region of FIG. 6A, the blowing of the pulverized coal was intentionally stopped to reproduce the clogging of the pulverized coal, and only pure oxygen was blown into the experimental furnace 84. In region (a), the blowing of the pulverized coal, which plays a role as a coolant, was stopped, so the tuyere temperature increased and sometimes exceeded 2000°C.
図６（ウ）の領域では、空気供給配管５８から空気を実験炉８４に吹込み、酸素供給配管３２からの純酸素の供給を停止した。空気の送風温度は、空気圧縮機出側の温度を想定して１８０℃とした。また、最終的には空気の送風量を純酸素の送風量と同じ４５Ｎｍ３／ｈにした。このように空気を送風することで、羽口先温度は１０００〜１５００℃に低下した。 In the region of FIG. 6C, air was blown into the experimental furnace 84 from the air supply pipe 58, and the supply of pure oxygen from the oxygen supply pipe 32 was stopped. The air blowing temperature was set to 180° C. assuming the temperature on the outlet side of the air compressor. Further, finally, the air blowing rate was set to 45 Nm 3 /h, which is the same as the pure oxygen blowing rate. By blowing the air in this way, the tuyere temperature was lowered to 1000 to 1500°C.
このように、冷却材となる微粉炭の吹込みが何らかの理由により停止し羽口先温度が上昇したとしても、当該微粉炭の吹込みが停止したことを微粉炭の流量計で測定し、その後、空気を吹込むことで羽口先温度の上昇を抑制できることが確認された。そして、制御装置９０を用いて空気の吹込み量を制御し、純酸素と空気との吹込み量の比率を変えることで、純酸素をのみを吹込んだ場合の温度から、空気のみを吹込んだ場合の温度までの間に羽口先温度を制御できる。このように空気の吹込み量を制御することで、羽口先温度を制御できるので、これにより、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できる。 In this way, even if the blowing of pulverized coal as a coolant is stopped for some reason and the tuyere temperature rises, it is measured with a pulverized coal flowmeter that the blowing of the pulverized coal has stopped, and then, It was confirmed that blowing in air could suppress the rise in tuyere temperature. Then, by controlling the blowing amount of air using the control device 90 and changing the ratio of the blowing amounts of pure oxygen and air, only the air is blown from the temperature when only pure oxygen is blown. The tuyere temperature can be controlled up to the temperature when it is included. Since the tuyere temperature can be controlled by controlling the air blowing amount in this way, it is possible to prevent the tuyere blockage while suppressing the rise of the tuyere temperature.
（実施例２）
次に、酸素高炉設備１８を用いた酸素高炉操業方法の効果を、同じラボ実験設備を用いて確認した実施例２を説明する。実施例２においても、酸素供給配管３２から常温の純酸素４５Ｎｍ３／ｈと、微粉炭配管４２から溶銑１ｔ当たり３３０ｋｇに相当する量の微粉炭と、を羽口設備１４を通じて実験炉８４に吹込んでコークスを燃焼させた。なお、内部監視孔のガラスを保護するために、通常時においても少量の窒素を流した。羽口先温度は、バーナー７２の中央部に設けられた内部監視孔の後方に設置された２色式放射温度計８６（株式会社チノー社製、ＩＲ−ＦＬ）を用いて測定した。
(Example 2)
Next, Example 2 in which the effect of the oxygen blast furnace operating method using the oxygen blast furnace equipment 18 was confirmed using the same laboratory experiment equipment will be described. Also in Example 2, pure oxygen at a normal temperature of 45 Nm 3 /h from the oxygen supply pipe 32 and pulverized coal in an amount corresponding to 330 kg per ton of hot metal from the pulverized coal pipe 42 were blown into the experimental furnace 84 through the tuyere facility 14. Then I burned the coke. In order to protect the glass of the internal monitoring hole, a small amount of nitrogen was flowed even in normal times. The tuyere temperature was measured using a two-color radiation thermometer 86 (IR-FL manufactured by Chino Co., Ltd.) installed behind an internal monitoring hole provided in the central portion of the burner 72.
図７は、羽口先温度の時間変化を示すグラフである。図７において、横軸は時間（秒）であり、縦軸は羽口先温度（℃）である。図７の（ア）の領域は、純酸素と微粉炭とを実験炉８４に吹込んだ場合の羽口先温度の時間変化を示す。（ア）の領域では、純酸素を吹込んでいるものの冷却剤としての微粉炭を吹込んでいるので、羽口先温度は１５００から２０００℃になった。 FIG. 7 is a graph showing the time variation of the tuyere tip temperature. In FIG. 7, the horizontal axis represents time (second) and the vertical axis represents tuyere temperature (° C.). The area (A) of FIG. 7 shows the time variation of the tuyere temperature when pure oxygen and pulverized coal are blown into the experimental furnace 84. In the region (a), since pure oxygen was blown, but pulverized coal as a coolant was blown, the tuyere temperature increased from 1500 to 2000°C.
図７の（イ）の領域では、微粉炭詰りを再現するために微粉炭の吹込みを意図的に停止させ、純酸素のみを実験炉８４に吹込んだ。（イ）の領域では、冷却剤としての役割を担う微粉炭の吹込みが停止されたので、羽口先温度は上昇し、２５００℃を超える場合もあった。 In the region (a) of FIG. 7, in order to reproduce the clogging of the pulverized coal, the blowing of the pulverized coal was intentionally stopped and only pure oxygen was blown into the experimental furnace 84. In region (a), the blowing of pulverized coal, which plays a role as a coolant, was stopped, so the tuyere temperature increased and sometimes exceeded 2500°C.
図７の（ウ）の領域では、窒素供給配管６８からの窒素を実験炉８４に吹込み、酸素供給配管３２からの純酸素の供給を停止した。窒素の送風温度は、窒素圧縮機出側の温度を想定して１８０℃とした。また、最終的には窒素の送風量を純酸素と同じ４５Ｎｍ３／ｈにした。このように窒素を送風することで、羽口先温度は１５００℃以下に低下した。なお、本実施例で温度測定に使用したＩＲ−ＦＬは８８０℃以下の温度が測定できない。このため、図７の（ウ）の温度が８８０℃以下の部分は平らな波形となっている。実施例１，２では、実験炉であるため熱損失が大きいので、羽口先温度のレベルは実機高炉とは異なるが、微粉炭詰りにより羽口先温度の上昇を抑制できることが確認できた。 In the region (c) of FIG. 7, nitrogen from the nitrogen supply pipe 68 was blown into the experimental furnace 84, and the supply of pure oxygen from the oxygen supply pipe 32 was stopped. The blowing temperature of nitrogen was set to 180° C. assuming the temperature on the outlet side of the nitrogen compressor. Finally, the blowing rate of nitrogen was set to 45 Nm 3 /h, which is the same as that of pure oxygen. By blowing nitrogen in this way, the tuyere temperature decreased to 1500° C. or less. The IR-FL used for temperature measurement in this example cannot measure temperatures of 880° C. or lower. Therefore, the portion of FIG. 7C having a temperature of 880° C. or lower has a flat waveform. In Examples 1 and 2, since the heat loss was large because of the experimental furnace, it was confirmed that although the level of the tuyere temperature was different from that of the actual blast furnace, the rise of the tuyere temperature could be suppressed by the clogging of the pulverized coal.
（実施例３）
次に、酸素高炉設備１８を用いた酸素高炉操業方法の効果を、小型の試験高炉を用いて確認した実施例３を説明する。炉本体は、内容積３．９ｍ３、炉床径０．９５ｍφ、炉口径０．７ｍφ、炉高５．１ｍで、羽口は３本である。基本の試験条件は出銑量１２ｔ／ｄ、コークス使用量３５２ｋｇ／ｔ−溶銑、微粉炭使用量３２０ｋｇ／ｔ−溶銑、酸素使用量３８３Ｎｍ３／ｔ−溶銑である。微粉炭の吹込みを行わず酸素送風のみを行った場合は、炉内での棚吊が発生した。この棚吊は、羽口先温度の上昇に起因したＳｉＯ２よる高炉内での原料同士の接着が原因と考えられる。また、基本の試験条件において、微粉炭の吹込みトラブルが発生し、酸素送風を停止した場合は、羽口閉塞が発生した。
(Example 3)
Next, Example 3 in which the effect of the oxygen blast furnace operating method using the oxygen blast furnace facility 18 was confirmed using a small test blast furnace will be described. The furnace body has an inner volume of 3.9 m 3 , a hearth diameter of 0.95 mφ, a furnace throat diameter of 0.7 mφ, a furnace height of 5.1 m, and three tuyeres. The basic test conditions are 12 t/d of tapping amount, 352 kg/t-hot metal of coke, 320 kg/t-hot metal of pulverized coal, and 383 Nm 3 /t-hot metal of oxygen use. When only blasting oxygen was performed without blowing pulverized coal, shelving in the furnace occurred. It is considered that this hanging is caused by the adhesion of the raw materials in the blast furnace due to SiO 2 caused by the rise in the temperature of the tuyere. Under the basic test conditions, when pulverized coal blowing trouble occurred and oxygen blowing was stopped, tuyere blockage occurred.
次に、微粉炭の吹込みトラブルが発生した時に、酸素送風量を低下させつつ空気を送風した。最終的には酸素送風をゼロとし、空気を基本試験条件における酸素使用量と同じ３８３Ｎｍ３／ｔ−溶銑とした。これにより、羽口閉塞は発生しなかった。微粉炭の設備のトラブルが解消した後に、微粉炭の吹込みを開始するとともに、酸素送風量を増加させつつ、空気送風量を低下させ、問題なく、基本の試験条件に復帰させることができた。 Next, when a problem of blowing pulverized coal occurred, air was blown while reducing the amount of oxygen blown. Finally, oxygen blowing was set to zero, and air was set to 383 Nm 3 /t-hot metal, which is the same as the amount of oxygen used in the basic test conditions. As a result, tuyere blockage did not occur. After the trouble of the pulverized coal facility was resolved, the pulverized coal injection was started, and the air blowing amount was decreased while increasing the oxygen blowing amount, and it was possible to return to the basic test conditions without problems. ..
このように、冷却材となる微粉炭の吹込みが何らかの理由により停止し羽口先温度が上昇したとしても、当該微粉炭の吹込みが停止したことを微粉炭の流量計で測定し、その後、窒素を吹込むことで羽口先温度の上昇を抑制できることが確認された。そして、制御装置９０を用いて窒素の吹込み量を制御し、純酸素と窒素との吹込み量の比率を変えることで、純酸素をのみを吹込んだ場合の温度から、窒素のみを吹込んだ場合の温度までの間に羽口先温度を制御できる。このように空気の吹込み量を制御することで、羽口先温度を制御できるので、これにより、羽口先温度の上昇を抑制しつつ羽口閉塞を回避できる。 In this way, even if the blowing of pulverized coal as a coolant is stopped for some reason and the tuyere temperature rises, it is measured with a pulverized coal flowmeter that the blowing of the pulverized coal has stopped, and then, It was confirmed that blowing up nitrogen can suppress the rise in tuyere temperature. Then, by controlling the blowing amount of nitrogen by using the control device 90 and changing the ratio of the blowing amounts of pure oxygen and nitrogen, only nitrogen is blown from the temperature when only pure oxygen is blown. The tuyere temperature can be controlled up to the temperature when it is included. Since the tuyere temperature can be controlled by controlling the air blowing amount in this way, it is possible to prevent the tuyere blockage while suppressing the rise of the tuyere temperature.
また、実施例１、２では純酸素を吹込んだ例を示したが、純酸素に代えて酸素を５０体積％以上含む酸素富化空気と微粉炭を吹込んで酸素高炉の操業を実施した場合においても同様に、空気または窒素を吹込むことで羽口先温度の上昇を抑制しつつ羽口閉塞を回避できる。さらに、実施例１、２では、微粉炭詰りを想定した例を示したが、微粉炭に代えて廃プラスチックを吹込んだ場合であっても同様に効果が得られ、微粉炭に代えて、気体還元材（都市ガス、プロパンガス、製鉄所内で発生する副生ガス）を吹込んだ場合であっても同様の効果が得られる。 In addition, in Examples 1 and 2, an example in which pure oxygen was blown was shown, but when oxygen-enriched air containing 50% by volume or more of oxygen and pulverized coal were blown in place of pure oxygen to carry out the operation of the oxygen blast furnace. Similarly, by blowing air or nitrogen, the tuyere blockage can be avoided while suppressing the rise in the tuyere tip temperature. Furthermore, in Examples 1 and 2, an example in which pulverized coal clogging was assumed was shown, but the same effect can be obtained even when waste plastic is blown in place of pulverized coal, and instead of pulverized coal, Similar effects can be obtained even when a gas reducing material (city gas, propane gas, by-product gas generated in a steel plant) is blown.
１０ 酸素高炉設備
１２ 高炉
１４ 羽口設備
１６ 酸素高炉設備
１８ 酸素高炉設備
２０ 酸素供給設備
２１ 酸素供給設備
２２ 酸素製造装置
２４ 酸素配管
２６ 酸素圧縮機
２８ 高圧酸素配管
３０ 酸素貯蔵設備
３２ 酸素供給配管
３４ 酸素供給配管
４０ 微粉炭供給設備
４２ 微粉炭配管
４４ 微粉炭流量計
５０ 空気供給設備
５１ 空気供給設備
５２ 空気圧縮機
５４ 高圧空気配管
５６ 空気貯蔵設備
５８ 空気供給配管
５９ 空気供給配管
６０ 窒素供給設備
６２ 窒素圧縮機
６４ 高圧窒素配管
６６ 窒素貯蔵設備
６８ 窒素供給配管
７０ 羽口
７２ バーナー
７４ 気体還元材配管
８０ ラボ実験設備
８２ 炉壁
８４ 実験炉
８６ ２色式放射温度計
９０ 制御装置
10 Oxygen Blast Furnace Equipment 12 Blast Furnace 14 Tuyere Equipment 16 Oxygen Blast Furnace Equipment 18 Oxygen Blast Furnace Equipment 20 Oxygen Supply Equipment 21 Oxygen Supply Equipment 22 Oxygen Production Equipment 24 Oxygen Pipe 26 Oxygen Compressor 28 High Pressure Oxygen Pipe 30 Oxygen Storage Equipment 32 Oxygen Supply Pipe 34 Oxygen supply piping 40 Pulverized coal supply equipment 42 Pulverized coal piping 44 Pulverized coal flow meter 50 Air supply equipment 51 Air supply equipment 52 Air compressor 54 High pressure air piping 56 Air storage equipment 58 Air supply piping 59 Air supply piping 60 Nitrogen supply equipment 62 Nitrogen compressor 64 High-pressure nitrogen piping 66 Nitrogen storage equipment 68 Nitrogen supply piping 70 Tuyere 72 Burner 74 Gas reducing agent piping 80 Laboratory experimental equipment 82 Furnace wall 84 Experimental furnace 86 Two-color radiation thermometer 90 Controller
Claims (5)
空気の圧力を高める圧縮機と、
前記圧縮機によって圧力が高められた高圧空気を貯蔵する空気貯蔵設備と、
気体還元材および／または固体還元材の流量を測定する流量計と、
前記空気貯蔵設備から前記羽口への前記高圧空気の供給を制御する制御装置と、
を有する、酸素高炉設備。 An oxygen blast furnace facility for operating by supplying oxygen and a gas reducing agent and/or a solid reducing agent into a blast furnace from tuyere,
A compressor that increases the pressure of air,
An air storage facility for storing high-pressure air whose pressure is increased by the compressor,
A flow meter for measuring the flow rate of the gas reducing agent and/or the solid reducing agent,
A control device for controlling the supply of the high-pressure air from the air storage facility to the tuyere,
With oxygen blast furnace equipment.
窒素の圧力を高める圧縮機と、
前記圧縮機によって圧力が高められた高圧窒素を貯蔵する窒素貯蔵設備と、
気体還元材および／または固体還元材の流量を測定する流量計と、
前記窒素貯蔵設備から前記羽口への前記高圧窒素の供給を制御する制御装置と、
を有する、酸素高炉設備。 An oxygen blast furnace facility for operating by supplying oxygen and a gas reducing agent and/or a solid reducing agent into a blast furnace from tuyere,
A compressor that increases the pressure of nitrogen,
A nitrogen storage facility for storing high-pressure nitrogen whose pressure is increased by the compressor,
A flow meter for measuring the flow rate of the gas reducing agent and/or the solid reducing agent,
A control device for controlling the supply of the high-pressure nitrogen from the nitrogen storage facility to the tuyere,
With oxygen blast furnace equipment.
前記気体還元材および／または固体還元材の流量が予め定められた流量以下になった場合に前記制御装置は、前記空気貯蔵設備から前記羽口に前記高圧空気を供給する、酸素高炉の操業方法。 A method for operating an oxygen blast furnace using the oxygen blast furnace facility according to claim 1,
A method for operating an oxygen blast furnace, wherein the control device supplies the high pressure air from the air storage facility to the tuyere when the flow rate of the gas reducing agent and/or the solid reducing agent becomes equal to or lower than a predetermined flow rate. ..
前記酸素は、酸素を５０体積％以上含む酸素富化空気であり、
前記気体還元材および／または固体還元材の流量が予め定められた流量以下になった場合に前記制御装置は、前記空気貯蔵設備から前記羽口に前記高圧空気を供給して酸素を５０体積％未満含む酸素富化空気に希釈する、酸素高炉の操業方法。 A method for operating an oxygen blast furnace using the oxygen blast furnace facility according to claim 1,
The oxygen is oxygen-enriched air containing 50% by volume or more of oxygen,
When the flow rate of the gas reducing agent and/or the solid reducing agent becomes less than or equal to a predetermined flow rate, the control device supplies the high pressure air from the air storage facility to the tuyere to supply 50% by volume of oxygen. Operating method of oxygen blast furnace, diluting to oxygen-enriched air containing less than.
前記気体還元材および／または固体還元材の流量が予め定められた流量以下になった場合に前記制御装置は、前記窒素貯蔵設備から前記羽口に前記高圧窒素を供給する、酸素高炉の操業方法。 A method for operating an oxygen blast furnace using the oxygen blast furnace facility according to claim 2,
When the flow rate of the gas reducing agent and/or the solid reducing agent becomes less than or equal to a predetermined flow rate, the control device supplies the high pressure nitrogen from the nitrogen storage facility to the tuyere, the operating method of the oxygen blast furnace ..
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| CN113188338A (en) * | 2021-05-18 | 2021-07-30 | 云南驰宏锌锗股份有限公司 | Metallurgical stove gas safety, spray gun interlocking control protection system |
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| CN113188338A (en) * | 2021-05-18 | 2021-07-30 | 云南驰宏锌锗股份有限公司 | Metallurgical stove gas safety, spray gun interlocking control protection system |
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