WO1999054512A1 - Method of judging slag forming state in electric furnace steel production and method of operating electric furnace - Google Patents
Method of judging slag forming state in electric furnace steel production and method of operating electric furnace Download PDFInfo
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- WO1999054512A1 WO1999054512A1 PCT/JP1998/001828 JP9801828W WO9954512A1 WO 1999054512 A1 WO1999054512 A1 WO 1999054512A1 JP 9801828 W JP9801828 W JP 9801828W WO 9954512 A1 WO9954512 A1 WO 9954512A1
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- WIPO (PCT)
- Prior art keywords
- electric furnace
- slag
- molten steel
- forming
- molten
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Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
- C21C5/5211—Manufacture of steel in electric furnaces in an alternating current [AC] electric arc furnace
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
- C21C5/42—Constructional features of converters
- C21C5/46—Details or accessories
- C21C5/4673—Measuring and sampling devices
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
- C21C5/5229—Manufacture of steel in electric furnaces in a direct current [DC] electric arc furnace
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
- C21C5/54—Processes yielding slags of special composition
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/06—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces with movable working chambers or hearths, e.g. tiltable, oscillating or describing a composed movement
- F27B3/065—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces with movable working chambers or hearths, e.g. tiltable, oscillating or describing a composed movement tiltable
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/08—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces heated electrically, with or without any other source of heat
- F27B3/085—Arc furnaces
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
- F27B3/28—Arrangement of controlling, monitoring, alarm or the like devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D17/00—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases
- F27D17/008—Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases cleaning gases
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D19/00—Arrangements of controlling devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/15—Tapping equipment; Equipment for removing or retaining slag
- F27D3/1545—Equipment for removing or retaining slag
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/52—Manufacture of steel in electric furnaces
- C21C2005/5288—Measuring or sampling devices
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C2300/00—Process aspects
- C21C2300/02—Foam creation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D19/00—Arrangements of controlling devices
- F27D2019/0006—Monitoring the characteristics (composition, quantities, temperature, pressure) of at least one of the gases of the kiln atmosphere and using it as a controlling value
- F27D2019/0012—Monitoring the composition of the atmosphere or of one of their components
- F27D2019/0015—Monitoring the composition of the exhaust gases or of one of its components
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Definitions
- the present invention relates to a method for determining slag forming in electric furnace steelmaking and a method for operating an electric furnace using the method, and particularly to a method for determining the suitability of slag forming generated in a refining process in an electric furnace in exhaust gas. together judged by amount of NO x measurement is a technique to operate completely cut off while the contact between the molten steel and the atmosphere by adjusting the slag 'forming state.
- the steelmaking method using an electric arc furnace has the following advantages over the normal steelmaking method combining a blast furnace and a converter for mass production (hereinafter referred to as blast furnace-converter steelmaking method). ing.
- the initial capital investment is smaller than that of the blast furnace first converter steelmaking method.
- the basic phenomena of the denitrification and nitrification reaction of the molten steel in the electric furnace are the same as those in the converter, and when the denitrification rate and the nitrification rate are balanced, the nitrogen in the molten steel during tapping It is considered that the content is determined.
- the electric furnace steelmaking method has the following major differences in equipment and operation compared to the converter steelmaking method.
- the reduction of nitrogen content in molten steel by the electric furnace steelmaking method has conventionally been achieved by using raw materials containing high carbon such as reduced iron and pig iron, or by injecting carbon material into the molten steel to reduce CO2 from the molten steel surface. This has been done by increasing the amount of gas generated and promoting so-called slag 'forming. In other words, the contact between the atmosphere gas and the molten steel surface was cut off by the formed slag to reduce the amount of nitrogen absorption caused by the above (1) and (2) and to promote the denitrification by the effect of (3).
- Japanese Unexamined Patent Publication No. 53-43003 discloses that “When dissolving a molten material, an oxidizing agent such as mill scale and dust is used. Available oxygen concentration in oxidizer (wt%) ⁇
- Japanese Unexamined Patent Publication No. 3-28312 discloses that "Carrier gas in which gas generated from a coke oven, a blast furnace, or a converter is used alone or in a mixture with molten steel in an electric furnace, and which contains solid carbon, aluminum ash, or flux ( Injecting slag-making agent).
- coke oven gas, blast furnace gas, and converter gas were used as means to increase the carbon concentration in the molten steel after meltdown.
- Japanese Patent Application Laid-Open No. 52-14751-3 discloses that in a steelmaking arc furnace, an electrode is made hollow, and an inert gas such as Ar and a reducing gas such as hydrocarbon are introduced into the arc through the hollow part. While supplying one or more species, make the carbon content in molten steel at the time of meltdown 0.1% or more, and make the average heating rate during the molten steel reduction period 10 ° C / min or less. '' Has been disclosed. Disclosure of the invention
- the principle of denitrification is the diffusion and discharge of nitrogen into the CO gas bubbles generated in the steel bath in the arc-type electric furnace steelmaking, as in the converter steelmaking method. Is understood. Therefore, the higher the decarburization rate from molten steel, the more denitrification is promoted. However, even if the amount of generated CO gas is increased to promote denitrification, it is good as long as the CO gas is generated, but at the end of operation when the amount of generated CO gas is reduced, the absorption from the arc spot is reduced. If the nitriding rate exceeds the denitrifying rate, the nitrogen content in the molten steel will increase as the operation proceeds.
- the molten steel temperature does not reach the target tapping temperature even if the carbon concentration in the molten steel is reduced.In the last stage of such operation, the amount of nitrogen absorption in the heating process is increased. Due to its large size, the nitrogen content in molten steel during tapping is often the same as in normal operation, regardless of the method used to inject the carbon material. Therefore, it is difficult to stably obtain molten steel having a low nitrogen content by simply using a high carbon content raw material or injecting a carbonaceous material by using the above-described technology. In addition, some carbon materials used have a high nitrogen content, so the injection of the carbon material may instead increase the nitrogen content in the molten steel, and it was necessary to select a carbon material.
- the appropriateness of slag off O one timing conditions occurring in an electric furnace steelmaking co Enabling determined by N_ ⁇ x amount measurement in the exhaust gas, the molten steel and the atmosphere by adjusting the forming conditions The aim is to provide a method for operating an electric furnace that completely cuts off the contact and constantly achieves a low nitrogen level at the time of tapping, or reduces power consumption.
- Fig. 1 shows an arc-type electric furnace embodying the present invention and a slag It is a longitudinal cross-sectional view which shows a trimming state.
- FIG. 2 is a longitudinal sectional view showing an example of a device for sucking exhaust gas.
- FIG. 3 is a graph showing the change over time of the NO x amount in the exhaust gas in the operation of the comparative example.
- FIG. 4 is a diagram showing the change over time in the amount of NO x in the exhaust gas in the operation of Example 1.
- Figure 5 is a graph showing a change with time of the NO x amount in the exhaust gas in the operation of the second embodiment.
- FIG. 6 is a diagram showing the relationship between the wear thermal efficiency of the cumulative N_ ⁇ x amount and the molten steel in the first charge operation.
- FIG. 7 is a diagram showing the relationship between the heat transfer efficiency and the power consumption index in operation.
- FIG. 8 is a diagram showing the relationship between the carbon content in steel and the nitrogen content in steel.
- the inventor studied grasping the slag forming state generated in the electric furnace. As a result, paying attention to the formation of the New Omicron chi at the contact point of the atmosphere and the molten steel (arc spot), it can be prevented The better follower one timing state of the slag in contact with molten steel and the atmosphere is, New Omicron chi occurs Thought not to. While working diligently to realize this idea, he discovered that the amount of ⁇ ⁇ ⁇ generated was closely related to the basic unit of electric power in the electric furnace operation, and completed the present invention.
- the present invention when producing molten steel by melting, refining, and raising the temperature of an iron scrap sequentially in an electric arc furnace, the amount of exhaust gas was measured during the refining and raising the temperature of the molten metal.
- This is a method for determining slag / forming in electric furnace steelmaking, wherein the state of slag / forming is determined based on the slag / forming.
- the present invention is characterized in that the scouring period is started at a time when the melting of the iron scrap is completed and the molten metal surface becomes flat, or at a time when the molten metal temperature exceeds 1550 ° C. This is a method for determining slag / forming in electric steelmaking.
- the present invention provides a method for producing molten steel by sequentially melting, refining, and raising the temperature of an iron scrap in an electric arc furnace, based on the determination of the slag forming state described in claim 1 during the refining of the molten metal and during the temperature raising period.
- a method of operating an electric furnace comprising: blowing a carbon material into slag so that molten steel is covered with slag; and forming the slag.
- the slag-forming conditions were evaluated by cumulative value of the exhaust gas in the amount of NO x was measured from the time of burn through material, the cumulative N_ ⁇ x amount
- This is a method of operating an electric furnace characterized by injecting carbon material into slag and forming slag so that the molten metal is covered with slag during the refining and heating period of the molten metal in order to keep it below 2000 ppm ⁇ min. .
- the present invention provides that the carbon material is coke powder having a diameter of 0.2 mm or less, or the iron scrap contains one or two selected from molten pig iron, solid pig iron, reduced iron, and iron carbide. This is a method of operating an electric furnace, characterized in that more than one kind is blended to make a main raw material.
- the present invention is characterized in that 40 to 60 wt% of the main raw material is molten pig iron and Z or solid pig iron, or the molten steel is a low nitrogen molten steel having a nitrogen content of less than 70 ppm. It is also a method of operating electric furnaces.
- the slag-forming state refers to the degree to which the molten steel is covered with the formed slag, and if it is completely covered, including the arc spot of the electrode of the electric furnace, the generation of ⁇ ⁇ ⁇ ⁇ is zero. Most preferred. Since the slag-forming conditions in an electric furnace in this onset facie as judged by Nyu_ ⁇ ⁇ Ryohaka constant in the exhaust gas, so that the conventional operating Four relied on feeling Isseki timing conditions can be accurately grasped become. By controlling the forming state, nitrogen absorption during the refining and heating periods can be prevented, and the nitrogen content in the molten steel can be maintained at a low level.
- the molten metal surface is reliably covered with the formed slag, heat diffusion from the molten metal can be prevented, and the power consumption per unit of operation can be greatly reduced.
- the present invention also slag in an electric furnace, and evaluated by the cumulative value of the New Omicron chi amount in the exhaust gas to be measure the forming state, by paying the cumulative Nyu_ ⁇ chi amount in a predetermined range, in the molten steel It will be possible to control the nitrogen content or to operate the electric furnace at a specific power consumption.
- the slag 9 formed by the scouring reaction contains a part of the gas and foams as shown in FIG. 1, and its height is increased so as to cover the molten metal surface.
- the nitriding of the molten steel 10 at the arc spot is due to the intrusion of the atmosphere into the arc spot, and when the atmosphere enters, the denitrification and NO x occur even occurs, the NO x is mixed in exhaust gas on the molten steel surface.
- One of the present invention includes a base that this part of the exhaust gas sucked in flue 1 1 as shown in FIG. 2, to measure the N_ ⁇ x amount of the suction gas in the NO x measuring device 1 5 I do. That is, the air entering the arc spot detected by generated N_ ⁇ x, it is to determine the appropriateness of slag-forming conditions.
- Another present invention based on the appropriateness determination of the slag Fomi ing state obtained by measurement of the N_ ⁇ x amount was considered to be break contact of the molten steel and the atmosphere in the seminal ⁇ and heating period. In other words, based on the above determination, the slag-forming state is improved to prevent nitrogen absorption, and the arc spot is completely covered with the formed slag.
- This slag forming As an operation for improving the condition, the present invention employs the injection of carbonaceous material into the slag. More specifically, as shown in FIG. This generates CO gas and increases the height of the slag 9 that has been reduced. Conventionally, this operation of improving the slag forming state has been performed by the operator according to the operating conditions (when the electrode is no longer covered with the slag, the sound of the arc increases). The operation will be computerized, and stable nitrogen absorption prevention during scouring and heating will be achieved.
- the determination of the suitability of the slag / forming during the operation of the electric furnace is performed, for example, by measuring the N ⁇ ⁇ ⁇ x Estimating the quantity by its cumulative value allows quantification.
- the measured amount of exhaust gas in the exhaust gas is accumulated in measurement records at predetermined intervals (such as at 30-second intervals), and the accumulated amount of exhaust gas is set to 2000 ppm min or less (also referred to as a predetermined range).
- the heat dissipation from the molten metal is performed by performing the slag forming operation to keep the accumulated N ⁇ x amount within a predetermined range.
- the method of operating an electric furnace at a low power consumption unit with improved heat transfer efficiency is achieved.
- the reason why the predetermined range is set to 2000 ppm ⁇ min or less is that if the value exceeds this value, the heat transfer efficiency to molten steel decreases to the conventional level.
- the slag / forming state is improved. It is preferred that the carbonaceous material be a coke powder of 0.2 mm or less.
- coke powder obtained from a dust remover of an ironworks CDQ facility (coke dry fire extinguishing facility) can be preferably used.
- molten pig iron, solid pig iron, reduced iron, and iron carbide when one or more selected from molten pig iron, solid pig iron, reduced iron, and iron carbide are blended as a part of the main raw material of the electric furnace, the molten pig iron and the solid pig iron are mixed. At least 40-60 wt% was used.
- the denitrification effect by gas is achieved in addition to the above-mentioned nitrogen absorption prevention operation.
- the present invention defines low nitrogen molten steel as less than 70 ppm. The reason is that if it is more than 70 ppm, high-grade steel products cannot be manufactured.
- An arc type electric furnace 1 having a capacity of 100 tons as shown in FIG. 1 was used, and the tapping port 5 was completely closed to produce a low-nitrogen steel.
- a measuring device for the amount of N ⁇ x in the exhaust gas (usually using a NO x measuring device 15 consisting of an infrared gas analyzer) was attached to the flue 11 and operation was performed while measuring the value. .
- melt down After 40 minutes Since the melt surface became flat, it was judged that all of the raw materials had completely melted (hereinafter referred to as melt down). The determination of melt-down may be made when the temperature of the molten metal exceeds 1550 ° C.
- the carbonaceous material used in this operation was coke powder with a particle size range of 0.1 to 0.2 mm, and the N content of the obtained molten steel was 100 ppm.
- the same operation as in the above comparative example was performed until melt down, and carbon material was injected along with acid supply immediately after the refining period after melt down, and the slag forming determination method and the electric furnace operation method according to the present invention were performed.
- the carbonaceous material used is coke powder with a particle size of 0.2 mm or less collected by the dust collector of the CDQ facility at the steelworks.
- Figure 6 shows the relationship between the cumulative generation amount and the molten steel wearing thermal efficiency of N_ ⁇ x in 1 charge operation. From Fig. 6, it is clear that the longer the operation where the molten metal surface and the arc are covered with the formed slag, the heat diffusion is reduced, and the heat of the arc is heated to the molten steel.
- the heat transfer efficiency (7)%) is defined as follows.
- the input power varies depending on the scrap and hot metal used until the raw material burns down (called MD). Therefore, the heat input and heat output between the time of MD and tapping (shown as TAP) were compared, and this was defined as the heat transfer efficiency. That is, the heat transfer efficiency (7%) was obtained by the following equation.
- E is the input power [KwhZch] (the power input from MD to TAP).
- C 2 represents the heat input by the C + 0-CO reaction is defined by the following equation.
- TAP C C concentration in molten steel at TAP
- Fig. 6 there is a correlation between the cumulative NO x value and the heat transfer efficiency.
- the measured NO x amount in the exhaust gas is accumulated at a certain measurement cycle (30 seconds interval, etc.), and the accumulated N ⁇ x amount is shown in Fig. 6.
- thermal diffusion is suppressed and an electric furnace operating method with a 10% or more increase in heating efficiency is achieved.
- Fig. 7 shows the relationship between the above heat transfer efficiency and power consumption rate. If the heat transfer efficiency can be controlled to about 60%, the power consumption rate can be reduced by 20% compared to the conventional operation. This result suggests that the present invention is useful not only for the production of low-nitrogen molten steel but also for the production of all types of steel, such as operation using only scrap.
- Fig. 8 summarizes the relationship between carbon and nitrogen in molten steel. Also in this case, there was a clear difference in the nitrogen absorption between the case where the present invention was applied and the case where the present invention was not applied.
- the quality of the slag forming state in electric steelmaking can be measured by using the equipment.
- this determination of the forming state as a control index and operating, it has become possible to stably produce low-nitrogen molten steel.
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- General Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Environmental & Geological Engineering (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP03461397A JP3743095B2 (ja) | 1997-02-19 | 1997-02-19 | 電気炉製鋼におけるスラグ・フォーミングの判定方法及び電気炉の操業方法 |
EP98914125A EP1006201A4 (en) | 1997-02-19 | 1998-04-21 | METHOD FOR ASSESSING THE SLAG SHAPING STATE IN ELECTRIC OVEN STEEL GENERATION AND FOR OPERATING AN ELECTRIC FOUNTAIN |
US09/445,960 US6375701B1 (en) | 1998-04-21 | 1998-04-21 | Method of judging slag forming state in electric furnace steel production and method of operating electric furnace |
BR9810449-7A BR9810449A (pt) | 1998-04-21 | 1998-04-21 | Método de julgar espumação de escória em fabricação de aço por forno elétrico e método de operar forno elétrico |
PCT/JP1998/001828 WO1999054512A1 (en) | 1997-02-19 | 1998-04-21 | Method of judging slag forming state in electric furnace steel production and method of operating electric furnace |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP03461397A JP3743095B2 (ja) | 1997-02-19 | 1997-02-19 | 電気炉製鋼におけるスラグ・フォーミングの判定方法及び電気炉の操業方法 |
PCT/JP1998/001828 WO1999054512A1 (en) | 1997-02-19 | 1998-04-21 | Method of judging slag forming state in electric furnace steel production and method of operating electric furnace |
Publications (1)
Publication Number | Publication Date |
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WO1999054512A1 true WO1999054512A1 (en) | 1999-10-28 |
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PCT/JP1998/001828 WO1999054512A1 (en) | 1997-02-19 | 1998-04-21 | Method of judging slag forming state in electric furnace steel production and method of operating electric furnace |
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US (1) | US6375701B1 (ja) |
EP (1) | EP1006201A4 (ja) |
WO (1) | WO1999054512A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103328913A (zh) * | 2010-11-29 | 2013-09-25 | 现代制铁株式会社 | 用于电炉的排渣门设备 |
CN115386678A (zh) * | 2022-08-02 | 2022-11-25 | 中南大学 | 一种基于“eaf-lf-vd-cc”炼钢流程的冶炼状态和炉号识别方法 |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6316075B1 (en) | 1998-02-04 | 2001-11-13 | Mannington Mills, Inc. | Surface coverings containing fused recycled material and processes of making the same |
KR100797342B1 (ko) * | 2001-07-13 | 2008-01-22 | 주식회사 포스코 | 전기로 보일링 판정방법 |
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LU81207A1 (fr) * | 1979-04-30 | 1980-12-16 | Arbed | Procede d'affinage d'un bain de metal contenant des matieres refroidissantes solides |
JPS5687617A (en) * | 1979-12-19 | 1981-07-16 | Daido Steel Co Ltd | Steel making method using arc furnace |
JPS6049684B2 (ja) * | 1980-03-26 | 1985-11-05 | 住友金属工業株式会社 | 転炉のフオ−ミング検出方法 |
JPS5919170A (ja) * | 1982-07-23 | 1984-01-31 | Canon Inc | 印字装置 |
ATA155793A (de) * | 1993-08-04 | 1996-04-15 | Voest Alpine Ind Anlagen | Verfahren zum herstellen einer metallschmelze und anlage zur durchführung des verfahrens |
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US5714113A (en) * | 1994-08-29 | 1998-02-03 | American Combustion, Inc. | Apparatus for electric steelmaking |
WO1997035038A1 (en) * | 1996-03-22 | 1997-09-25 | Steel Technology Corporation | Stable operation of a smelter reactor |
DE19827299C1 (de) * | 1998-06-19 | 2000-03-09 | Schloemann Siemag Ag | Verfahren und Vorrichtung zur Stahlerzeugung in einem Ofengefäß |
EP2264435A3 (en) * | 2000-06-26 | 2011-12-07 | Murray Thomson | Method for improved process control in combustion applications |
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1998
- 1998-04-21 US US09/445,960 patent/US6375701B1/en not_active Expired - Fee Related
- 1998-04-21 EP EP98914125A patent/EP1006201A4/en not_active Withdrawn
- 1998-04-21 WO PCT/JP1998/001828 patent/WO1999054512A1/ja not_active Application Discontinuation
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JPS5919170B2 (ja) * | 1978-12-26 | 1984-05-02 | 大同特殊鋼株式会社 | 溶鋼の精錬方法 |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103328913A (zh) * | 2010-11-29 | 2013-09-25 | 现代制铁株式会社 | 用于电炉的排渣门设备 |
CN115386678A (zh) * | 2022-08-02 | 2022-11-25 | 中南大学 | 一种基于“eaf-lf-vd-cc”炼钢流程的冶炼状态和炉号识别方法 |
CN115386678B (zh) * | 2022-08-02 | 2023-11-21 | 中南大学 | 一种基于“eaf-lf-vd-cc”炼钢流程的冶炼状态和炉号识别方法 |
Also Published As
Publication number | Publication date |
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EP1006201A4 (en) | 2005-07-27 |
EP1006201A1 (en) | 2000-06-07 |
US6375701B1 (en) | 2002-04-23 |
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