EP3752650B1 - Procédé d'affinage de métal fondu faisant appel à un convertisseur - Google Patents

Procédé d'affinage de métal fondu faisant appel à un convertisseur Download PDF

Info

Publication number
EP3752650B1
EP3752650B1 EP19704797.0A EP19704797A EP3752650B1 EP 3752650 B1 EP3752650 B1 EP 3752650B1 EP 19704797 A EP19704797 A EP 19704797A EP 3752650 B1 EP3752650 B1 EP 3752650B1
Authority
EP
European Patent Office
Prior art keywords
converter
powdered material
side wall
slag
nozzle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
EP19704797.0A
Other languages
German (de)
English (en)
Other versions
EP3752650A1 (fr
Inventor
Sabrine KHADHRAOUI
Satyajit Das
Hans-Jürgen ODENTHAL
Fabian Krause
Andreas Kemminger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SMS Group GmbH
Original Assignee
SMS Group GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SMS Group GmbH filed Critical SMS Group GmbH
Publication of EP3752650A1 publication Critical patent/EP3752650A1/fr
Application granted granted Critical
Publication of EP3752650B1 publication Critical patent/EP3752650B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/32—Blowing from above
    • 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
    • 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
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/0087—Treatment of slags covering the steel bath, e.g. for separating slag from the molten metal
    • 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
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/064—Dephosphorising; Desulfurising
    • C21C7/0645—Agents used for dephosphorising or desulfurising
    • 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
    • F27D3/0025—Charging or loading melting furnaces with material in the solid state
    • F27D3/0026—Introducing additives into the melt
    • 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
    • F27D3/0033—Charging; Discharging; Manipulation of charge charging of particulate material
    • 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
    • F27D3/18—Charging particulate material using a fluid carrier
    • 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
    • F27D3/18—Charging particulate material using a fluid carrier
    • F27D2003/185—Conveying particles in a conduct using a fluid

Definitions

  • the present invention relates to a method for refining molten metal using a converter, e.g. a converter steelmaking method for producing steel from molten iron.
  • a converter e.g. a converter steelmaking method for producing steel from molten iron.
  • the Linz-Donauwitz-process (also known as basic Oxygen steelmaking or Oxygen converter process) is a steel making process in which Oxygen is blown onto the surface of carbon-rich molten pig iron (iron bath) in a converter.
  • molten pig iron is introduced into a steelmaking converter, e.g. from a blast furnace, to form a bath of molten metal.
  • Suitable converters are known in the art, their design being e.g. based on a Bessemer converter.
  • the converter may be formed as a metallurgical vessel as for example disclosed in the patent specification of GB 1 276 029 .
  • a converter can be a metallurgical vessel, which can be held using e.g.
  • an encircling support ring having two trunnions defining a horizontal pivoting axis about which the converter can be rotated from a vertical orientation in which the steelmaking process is carried out into a tilted orientation for pouring or discharging the steel out of the converter.
  • Oxygen For refining the molten iron, Oxygen, usually high purity Oxygen, is blown at high pressure and at supersonic speed onto and into the surface of the iron bath usually through a water-cooled lance comprising one or more nozzles at its tip.
  • the Oxygen ignites carbon dissolved in the molten metal to form carbon monoxide and carbon dioxide thus lowering carbon content of the molten metal.
  • Fluxes, in particular dephosphorization agents, such as e.g. burnt lime are fed into the vessel to form slag and to absorb impurities (including phosphor) during the steelmaking process.
  • Magnesium oxide (MgO) containing agents may be added also for protecting an inner converter lining. Blowing the Oxygen onto and into the molten metal stirs the molten metal such that metal and fluxes may form an emulsion which facilitates the refining process.
  • a drawback which may be associated with a use of powdered lime is a possibly large loss of the lime as converter dust e.g. to gas cleaning plant systems. This may be less of a problem for lime powders of larger grain size or for bulk lime.
  • bulk lime can be dissolved less efficiently and it was found that bulk lime can in particular not be dissolved in a foamy slag.
  • a foamy slag may be advantageous for refining processes as an amount of metal droplets residing in the slag is at maximum during foaming (which results in a high decarburisation rate), only little dephosphorization appears possible when using bulk lime.
  • the Patent GB 2 011 477 A discloses a method for refining molten metal using a converter comprising at least one side wall nozzle mounted to a side wall of the converter. Further, a molten metal bath is formed inside of the converter and a mixture of an essential oxygen free carrier gas and a powdered material is blown onto and into a slag formed at least partially on the surface of the bath of molten metal using the at least one side wall nozzle.
  • a disadvantage of the disclosed method is that the powdered material is blown at the hot spot of the converter and thus increased the loss of the powder to the dedusting system.
  • a further object of the present invention is to avoid complex control mechanisms for introducing Oxygen and solid materials into a metallurgical converter.
  • a method for refining molten metal, preferably molten iron, e.g. molten pig iron, using a converter, e.g. a metallurgical furnace, for example for making steel from molten pig iron.
  • molten metal preferably molten iron, e.g. molten pig iron
  • a converter e.g. a metallurgical furnace
  • the converter is a top blown converter including at least one upper nozzle mounted to a top lance for blowing oxygen onto a bath of molten metal.
  • at least one upper nozzle is movably assigned to an upper wall of the converter.
  • the at least one upper nozzle is mounted movably in a vertical direction to the converter and is included in a, preferably water cooled, vertical lance.
  • the vertical lance itself can be mounted movably to the converter and can be movable through a corresponding opening formed in the upper wall of the converter.
  • the converter can for example also be a combined blown converter where oxygen may be partially blown into the molten bath via bottom tuyeres, while further oxygen is blown onto the bath of molten metal from above via a top lance.
  • the converter can be a combined blown converter including at least one bottom nozzle and at least one upper nozzle.
  • the converter further comprises at least one side wall nozzle mounted to a side wall of the converter lower in a vertical direction than a horizontal pivoting axis of the converter, when the converter is in an upright orientation and the method comprises a step of forming a bath of molten metal inside of the converter.
  • molten iron may be charged into the converter directly or after a suitable pretreatment stage from a blast furnace.
  • the method comprise blowing Oxygen gas onto a surface of the bath of molten metal using the at least one upper nozzle.
  • the method may comprise blowing Oxygen gas from at least one bottom nozzle or tuyere into the bath of molten metal from below.
  • the Oxygen gas may be high purity Oxygen and may be blown into the bath of molten metal at high pressure (e.g. in between 200 and 2000 kilopascal) at supersonic speeds. Reacting with Carbon included in the bath of molten metal to produce carbon oxides, blowing the Oxygen gas onto the bath surface provides the effect of removing carbon from the molten metal.
  • An iron refining or steelmaking process using the converter in accordance with the invention involves a formation of a slag on the surface of a bath of molten metal.
  • the slag may e.g. be formed using fluxes fed into the converter to absorb impurities during the process.
  • the converter being a top blown converter, the slag may e.g. be formed mainly aside of a hot spot zone where the Oxygen gas from the at least one upper nozzle impinges the surface of the bath of molten metal.
  • slag and molten metal may be mixed forming a slag/metal emulsion possibly on top of a slag layer.
  • the method further comprises blowing a mixture of a carrier gas and powdered material onto and downwardly into the slag (and/or the slag/metal emulsion) formed at least partially on the surface of the bath of molten metal using the at least one side wall nozzle.
  • the side wall nozzle is preferably mounted to a respective side wall of the converter such that the mixture of carrier gas and powdered material is injected mainly into the slag and/or into a slag/metal emulsion, preferably avoiding the hot spot zone in the case of a top blown or combined blown converter.
  • the slag being the reaction zone for the powdered material, e.g. a powdered agent, in particular for powdered lime, efficiency in using solid input materials in the converter can be thus increased.
  • a powdered material e.g. a powdered agent, in particular for powdered lime
  • the powdered material comprises a dephosphorization agent selected from a group including lime powder, Calcium Oxide (CaO), and 2CaO.SiO 2 powder may be injected directly into the reaction zone, that is the slag, which results in a high reactivity in particular in terms of efficient continuous dissolution of the agent and efficient dephosphorization of the molten metal.
  • 2CaO.SiO 2 powder may in a preferred embodiment have a grain or particle size equal to or smaller than 2 mm, preferably in between 20 to 50 ⁇ m. It turned out that 2CaO.SiO 2 powder can advantageously dissolve P 2 O 5 in solid form and thus increase the phosphorus capacity in slag which leads to high dephosphorization efficiency.
  • the use of such dephosphorization agents may allow that e.g. using high amounts of lump lime with large grain size can be avoided.
  • avoiding a use of lump lime has been found to be advantageous for a steelmaking process, as lump lime usually dissolves only slowly and undissolved parts may remain even after the end of the process.
  • the side wall nozzles may provide the following additional advantage. For example, when oxygen is blown through bottom tuyeres in case of a combined blown converter into the bath of molten metal, the produced slag amount is usually much lower than in the case of a top blown converter. This results in lower iron loss as compared with the case of a top blown converter, however, also to limited dissolution of solid lime und thus insufficient dephosphorization.
  • the method may preferably further comprise blowing a mixture of an essentially Oxygen free carrier gas and the powdered material into the bath of molten metal from below the bath of molten metal using the at least one bottom nozzle. Blowing a gas from below into the metal bath helps stirring the bath and thus facilitates the refining process. Providing additionally powdered material from below increases the total injection rate of said powdered material without introducing further load on the at least one side wall nozzle.
  • the carrier gas (preferably all gas from the at least one side wall nozzle) is essentially Oxygen (O) free.
  • the carrier gas does not comprise Oxygen up to a tolerable Oxygen pollution, e.g. a residue Oxygen concentration e.g. below 1%, e.g. below 0,1%, e.g. below 0,01% (by weight).
  • the carrier gas is an inert gas, preferably free of Oxygen.
  • the inert gas may e.g. be selected from the group of noble gases and is preferably Argon (Ar).
  • the carrier gas may comprise Nitrogen (N), being preferably free of Oxygen.
  • an oxygen-free carrier gas is advantageous as thereby, the overall system requires less complex control.
  • introducing Oxygen only (or mainly) via the at least one upper nozzle, mounted to a vertical lance prevents a necessity to synchronize oxygen blowing rates between the at least one upper nozzle and the at least one side wall nozzle.
  • a similar effect may be achieved by using the side wall nozzle in the cases of a combined blown converter.
  • the at least one side wall nozzle is mounted to the side wall at a height in a vertical direction, the height being lower than a horizontal pivoting axis of the converter, when the converter is in an upright orientation.
  • Blowing the mixture of the essentially Oxygen free carrier gas and the powdered material comprises blowing the mixture of the essentially Oxygen free carrier gas and the powdered material downwardly into the slag.
  • the at least one side wall nozzle is mounted to the converter side wall underneath the pivoting axis, defined e.g. by the trunnions about which the converter may be tilted.
  • the at least one side wall nozzle is thus mounted in close proximity to the slag and/or to the slag/metal emulsion.
  • the at least one side wall nozzle is not used for introducing oxygen into the converter, but to introduce the powdered material, e.g. the powdered dephosphorization agent, for example powdered iime, directly into the slag or slag/metal emulsion being carried by an essentially oxygen-free gas.
  • the at least one side wall nozzle By mounting the at least one side wall nozzle underneath the trunnions or a trunnion ring, the at least one side wall nozzle is located in close proximity to the reaction zone, i.e. the slag.
  • the powder can easily reach the reaction zone with minimal gas pressure such that only a reduced amount of carrier gas is necessary which is in particular advantageous if noble gasses such as Argon are used as carrier gas.
  • Noble gasses such as Argon are used as carrier gas.
  • Nitrogen Nitrogen
  • Blowing powdered material onto a slag and/or the metal bath surface from above conventionally resulted in undesirably large losses of the powdered material.
  • powdered and gaseous materials cannot be fully introduced into the slag/and or the metal bath but are blown into an inner volume of the converter above the metal bath and the slag.
  • gaseous and powdered materials are often extracted from the converter and fed to a gas cleaning plant (GCP) for separating the gaseous and powdered materials.
  • GCP gas cleaning plant
  • a mean diameter of particles forming the powdered material is smaller than 2 mm, preferably smaller than 1 mm, more preferably smaller than 0,1 mm. It was found that for example by injecting powdered lime or lime fines with grain size ⁇ 2 mm via at least one side wall nozzle located close to the slag, the typical losses to the GCP system known from using small grain sized lime are avoided or minimized.
  • the at least one side wall nozzle is arranged on the side wall of the converter underneath the trunnion ring, such that the blown mixture of carrier gas and powdered material is directed to impinge directly into the slag and/or the slag/metal emulsion.
  • a corresponding injection angle is set accordingly.
  • the blowing of the mixture of the essentially Oxygen free carrier gas and the powdered material comprises blowing the mixture of the essentially Oxygen free carrier gas and the powdered material into the slag downwardly at an injection angle with respect to the horizontal pivoting axis, the injection angle being in between 1° and 60°, preferably in between 10° and 50°, more preferably in between 15° and 35°. It was found that in particular within these angle ranges, beneficial results could be achieved in terms of use efficiency of the powdered material, e.g. the powdered dephosphorization agent.
  • Blowing the mixture of the essentially Oxygen free carrier gas and the powdered material comprises blowing the mixture of the essentially Oxygen free carrier gas and the powdered material along a main blowing direction of the at least one side wall nozzle into the slag, wherein said main blowing direction of the at least one side wall nozzle forms an angle in between 45° and 89° with a main blowing direction of the upper nozzle.
  • the powdered material can be suitably directed to areas aside of a hot spot zone in a case of a top blown converter in which zone oxygen from the upper nozzle impinges the metal bath surface into areas where slag and/or slag/metal emulsion is usually formed.
  • the essentially Oxygen free carrier gas is blown at subsonic speed onto and into the slag.
  • an inner diameter of the side wall nozzle is essentially constant along a length direction of the side wall nozzle.
  • the use of nozzles having e.g. converging and diverging inner profiles such as Laval nozzles is avoided. It was found that a use of nozzles with such inner profile are subject to larger wear of inner surfaces by grinding of particles transported through the nozzles. In the case of Laval nozzles, such grinding may be attributed to the fact that a carrier gas may reach supersonic velocities while velocities of powder particles usually remain subsonic. Nozzles with an essentially constant inner diameter are therefore advantageous as inner surfaces are subject to less wear.
  • the powdered material comprises converter dust.
  • converter dust is mainly iron oxide in form of Fe 2 O 3 and may also contain dephosphorization agents, such as CaO. It turned advantageously out that the converter dust, if introduced through the side wall nozzles can be used as a substitute for iron ore and thus as a cooling agent for the slag or as a slag former. It turned out that the cooling effect can be beneficial for dephosphorization.
  • converter dust may be converter dust recycled from the same converter or from a different converter.
  • the converter dust can be recycled without briquetting. This is advantageous as briquetting processes can be avoided and as corresponding costs can be avoided.
  • the use of the inventive side wall nozzles allow for an efficient recycling of powdered material lost to the inner volume of the converter above the bath of molten metal and the slag.
  • converter dust may be recycled from the converter.
  • the method comprises extracting a mixture of gaseous materials and converter dust from an inner converter volume during the refining of the molten metal. Thereafter, the converter dust is separated from the gaseous materials and the separated converter dust is again blown onto and into the slag via the at least one side wall nozzle.
  • the efficiency of the use of the powdered material is further increased as powdered material which escaped the reaction zone can be recycled from the converter dust and again injected into the reaction zone, i.e. into the slag and/or the slag/metal emulsion.
  • the powdered material comprises a slag forming material, preferably lime powder, preferably CaO powder. It was found that the use of the inventive side wall nozzles leads to a high efficiency of dephosphorization. Further materials such as iron ore can be used e.g. for cooling purposes.
  • the mixture of an essentially Oxygen free carrier gas and powdered material further comprises iron ore, e.g. iron ore powder. It was found that this material further has an advantageous cooling effect on the melt. Further, even though MgO-containing agents may have a negative effect on dephosphorization, this negative effect is overcompensated by the highly efficient dephosphorization enabled by the use of the side wall nozzles. Therefore, in a preferred embodiment, the mixture of an essentially Oxygen free carrier gas and powdered material further comprises dolomite powder, preferably MgO. The addition of dolomite powder helps to protect an inner converter lining.
  • the powdered material may comprise foaming or anti-foaming materials.
  • foaming or anti-foaming materials may have several advantages. For example, slag foaming increases the total reaction surface of the metallic droplets in the slag and thus the impurities removal rate. However, excessive foaming may lead to slopping (slag overrunning from the converter mouth). Thus, by appropriately providing foaming or anti-foaming materials, slag formation can be controlled.
  • the side wall nozzles can be used to either enhance or suppress the slag foaming by blowing foaming or anti-foaming agents in powdered form into or onto the slag. For example, fine powder coke was found to increase the foam height while grain coke (size 1 to 2 mm) suppresses the foaming.
  • the mixture of an essentially Oxygen free carrier gas and the powdered material may further comprise pulverized fuel materials including carbon and/or aluminum containing materials.
  • pulverized fuel materials including carbon and/or aluminum containing materials.
  • FIG. 1 shows a schematic illustration of a converter to be used in a method for refining molten metal.
  • Fig. 1 schematically illustrates a converter 100, in the shown only exemplary case a top blown converter, to be used in a method for refining molten metal, e.g. molten pig iron, for producing steel.
  • a refractory lining 110 forms an upper wall 111, a side wall 113 (the side wall essentially rotationally symmetric around a vertical axis 607) and a bottom wall 115.
  • Fig. 1 shows the converter 100 schematically during a refining process where a bath 501 of molten metal, e.g. molten iron, is formed inside the converter, a surface 503 of the bath 501 being partially covered by slag 401.
  • the slag 401 is formed least partially on the surface 503 of the bath 501, in the shown example around a hot spot zone 510 of the surface 503 which is impinged by an oxygen stream 301 from an upper nozzle 121 included in a vertical lance 120.
  • the vertical lance is mounted movable to the converter 100 along a vertical axis 607 which coincides with a main blowing direction 607 of the upper nozzle 121.
  • the vertical lance itself can be mounted movably to the converter 100 and can be movable through a corresponding opening formed in the upper wall of the converter 100.
  • a splashing mode of the vertical lance 120 can be enabled where the stream of oxygen from the upper nozzle 121 is used to generate metal droplets from the bath 501 of molten metal into to the slag 401.
  • a slag-metal interface can be increased to thereby increase the reactivity of the slag 401.
  • Fig. 1 further shows a trunnion ring 105 (cross sections of said ring at both sides of the converter 100) which embraces the converter 100.
  • the trunnion ring 105 has respective trunnions 106 which define a horizontal pivoting axis 601 around which the converter 100 can be tilted to pour the liquid steel after the refining process out of the converter 100.
  • the figure further illustrates side wall nozzles 150 which are mounted to the side wall 113 underneath a plane perpendicular to the vertical axis 607 and including the horizontal axis 601.
  • the side wall nozzles 150 are mounted lower than the trunnions 106 or the trunnion ring 105, when the converter 100 is in its upright, vertical orientation in which the steelmaking or iron refining process is carried out inside of the converter 100.
  • the figure illustrates the possibility of using a plurality of side wall nozzles (four side wall nozzles 150 are visible) which may be arranged in a ring-like fashion around the side wall 113 of the converter 100.
  • Providing the side wall nozzles 150 allows the possibility that maintenance of the powder injectors, i.e. according to the invention the side wall nozzles 150, can be done separately from the vertical lance 120, and therefore, a malfunction/breakdown of one of the side wall nozzles 150 would not affect the blowing profile and the plant operation.
  • the nozzles 150 are mounted to the side wall 113 at respective injection angles ( ⁇ 1 , ⁇ 2 shown in the figure) with respect to the horizontal pivoting axis 601 such that a mixture 303 of an essentially Oxygen free carrier gas, e.g. Argon and/or Nitrogen, and powdered material, e.g. powdered lime, is injected into the slag 401 while essentially avoiding the hot spot area 510.
  • an essentially Oxygen free carrier gas e.g. Argon and/or Nitrogen
  • powdered material e.g. powdered lime
  • the injection angle is chosen such that a main blowing direction 603, 605 of each side wall nozzle is essentially along an orientation of the slag 401 such that the mixture 303 is not blown into the metal bath 501 but such that most of the powdered material is injected into the volume of the slag 401 and or a slag/metal emulsion.
  • the side wall nozzles 150 it is possible to use the side wall nozzles 150 to generate metal droplets from the bath 501 of molten metal into to the slag 401 by blowing onto the metal bath surface (similar to a splashing mode of the vertical lance). In this way, a slag-metal interface can be increased increasing the reactivity. Using the side wall nozzles 150 in this way, it becomes possible to keep operating the vertical lance 120 and the upper nozzle 121 at a suitable vertical distance from the metal bath to reduce wear on the vertical lance 120 thereby increasing its possible lifetime.
  • the powdered material e.g. the powdered lime or CaO
  • the side wall nozzles being provided in close proximity to the slag underneath the trunnion ring 105.
  • GCP gas cleaning plant
  • powdered lime can be dissolved well in a foamy slag also when the iron oxide content in the slag is low. Losses of powdered material to the GCP system can also be efficiently avoided by blowing of the powdered material into the slag via the side wall nozzles placed in close proximity to the slag underneath the trunnion ring. Yet a further advantage achieved by blowing the mixture of carrier gas and powdered material through the side wall nozzles 150 is that a high iron content in the slag, which conventionally may be required to dissolve e.g. lime, is no longer necessary which reduces refractory and increases iron yield.
  • an efficient dephosphorization can be achieved leading to a high quality end product, e.g. a low P-content steel with a Phosphorous (P) content as low as 50 ppm.
  • the inventive method thus may allow also for refining of lower-priced raw materials with high phosphorus content.
  • the at least one side wall nozzle is provided below the trunnion ring (pivoting axis), so that the at least one side wall nozzle is situated in short distance to the slag yet a further advantage arises.
  • the powder can then easily reach the reaction zone with minimal gas pressure (and thus minimal total gas amount). In the case when Ar-gas is used, this would lead to costs reduction and in the case of nitrogen, to less N-pickup of the bath.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Analytical Chemistry (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)

Claims (17)

  1. Procédé destiné à l'affinage d'un métal en fusion en utilisant un convertisseur (100) qui comprend au moins une buse de paroi latérale (150) qui est montée sur une paroi latérale (113) du convertisseur (100) plus bas, dans une direction verticale, qu'un axe de pivotement horizontal (601) du convertisseur (100), lorsque le convertisseur (100) se trouve dans une orientation dressée, le procédé comprenant les étapes suivantes dans lesquelles :
    on forme un bain (501) d'un métal en fusion à l'intérieur du convertisseur (100) ;
    on applique par soufflage un mélange (303) d'un gaz porteur essentiellement exempt d'oxygène et d'une matière pulvérulente sur, et en orientation descendante, dans un laitier (401) qui est formée au moins en partie sur la surface (503) du bain (501) du métal en fusion en utilisant ladite au moins une buse de paroi latérale (150) en formant un angle d'injection (α1, α2) par rapport à l'axe de pivotement horizontal (601), l'angle d'injection étant compris entre 1° et 60° ;
    caractérisé en ce que :
    le convertisseur (100) comprend en outre au moins une buse supérieure (121) qui est attribuée en mobilité à une paroi supérieure (111) du convertisseur (100) ; et dans lequel le procédé comprend en outre :
    le fait d'appliquer par soufflage de l'oxygène gazeux (301) sur une surface (503) du bain (501) du métal en fusion en utilisant ladite au moins une buse supérieure (121) ; et
    le mélange (303) est insufflé, en suivant une direction de soufflage principale (603, 605) de ladite au moins une buse de paroi latérale (150), jusque dans le laitier (401) ; dans lequel ladite direction de soufflage principale (603, 605) de ladite au moins une buse de paroi latérale (150) forme un angle qui se situe entre 45° et 89° par rapport à une direction de soufflage principale (607) de la buse supérieure (121).
  2. Le procédé conformément à la revendication 1, dans lequel l'angle d'injection (α1, α2) se situe entre 10° et 50°, de préférence entre 15° et 35°.
  3. Le procédé conformément à l'une quelconque des revendications 1 à 2, dans lequel le convertisseur (100) comprend en outre au moins une buse inférieure qui est montée sur une paroi inférieure (115) du convertisseur (100), le procédé comprenant en outre :
    le fait d'introduire un mélange d'un gaz porteur essentiellement exempt d'oxygène et d'une matière pulvérulente dans le bain (501) de métal en fusion à partir d'un endroit situé en dessous du bain (501) du métal en fusion en utilisant ladite au moins une buse inférieure.
  4. Le procédé conformément à l'une quelconque des revendications 1 à 3, dans lequel le fait d'insuffler le mélange (303) du gaz porteur essentiellement exempt d'oxygène et de la matière pulvérulente comprend :
    le fait d'insuffler le gaz porteur essentiellement exempt d'oxygène à une vitesse subsonique sur et dans le laitier (401).
  5. Le procédé conformément à l'une quelconque des revendications 1 à 4, dans lequel un diamètre interne de la buse de paroi latérale (150) est essentiellement constant sur une direction qui s'étend sur la longueur (603, 605) de la buse de paroi latérale (150) ; dans lequel le fait d'insuffler le mélange (303) du gaz porteur essentiellement exempt d'oxygène et de la matière pulvérulente comprend :
    le fait d'insuffler le gaz porteur essentiellement exempt d'oxygène à une vitesse subsonique sur et dans le laitier (401).
  6. Le procédé conformément à l'une quelconque des revendications 1 à 5, dans lequel la matière pulvérulente comprend de la poussière de convertisseur recyclée.
  7. Le procédé conformément à l'une quelconque des revendications 1 à 6, qui comprend en outre :
    le fait d'extraire un mélange de matières gazeuses et de poussière de convertisseur à partir d'un volume interne du convertisseur au cours de l'affinage du métal en fusion ;
    le fait de séparer la matière pulvérulente des matières gazeuses ; et
    le fait d'insuffler sur le laitier (401) la matière pulvérulente qui a été séparée, en passant par ladite au moins une buse de paroi latérale (150).
  8. Le procédé conformément à l'une quelconque des revendications 1 à 7, dans lequel la matière pulvérulente comprend un agent de déphosphoration, qui est choisi de préférence à partir d'un groupe qui comprend de la poudre de chaux, de la poudre de CaO et du 2CaO.SiO2.
  9. Le procédé conformément à l'une quelconque des revendications 1 à 8, dans lequel la matière pulvérulente comprend de la poudre de dolomite, de préférence du MgO.
  10. Le procédé conformément à l'une quelconque des revendications 1 à 9, dans lequel la matière pulvérulente comprend du minerai de fer.
  11. Le procédé conformément à l'une quelconque des revendications 1 à 10, dans lequel la matière pulvérulente comprend en outre des matières combustibles pulvérisées, y compris des matières qui contiennent du carbone et/ou de l'aluminium.
  12. Le procédé conformément à l'une quelconque des revendications 1 à 11, dans lequel la matière pulvérulente comprend des matières de transformation en mousse ou des matières qui s'opposent à la transformation en mousse.
  13. Le procédé conformément à l'une quelconque des revendications 1 à 12, dans lequel le gaz porteur représente un gaz inerte.
  14. Le procédé conformément à l'une quelconque des revendications 1 à 13, dans lequel le gaz porteur comprend de l'argon et/ou de l'azote.
  15. Le procédé conformément à l'une quelconque des revendications 1 à 14, dans lequel ladite au moins une buse supérieure (121) est montée en mobilité dans une direction verticale par rapport à la paroi supérieure (111) du convertisseur (100) par l'intermédiaire d'une lance verticale (120) qui a été refroidie avec de l'eau.
  16. Le procédé conformément à l'une quelconque des revendications 1 à 15, dans lequel un diamètre moyen des particules qui forment la matière pulvérulente est inférieur à 2 mm, de préférence inférieur à 1 mm et de manière plus préférée inférieur à 0,1 mm.
  17. Le procédé conformément à l'une quelconque des revendications 1 à 16, dans lequel le métal en fusion comprend du fer qui a été mis en fusion.
EP19704797.0A 2018-02-16 2019-02-11 Procédé d'affinage de métal fondu faisant appel à un convertisseur Active EP3752650B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN201841005906 2018-02-16
PCT/EP2019/053318 WO2019158479A1 (fr) 2018-02-16 2019-02-11 Procédé d'affinage de métal fondu faisant appel à un convertisseur

Publications (2)

Publication Number Publication Date
EP3752650A1 EP3752650A1 (fr) 2020-12-23
EP3752650B1 true EP3752650B1 (fr) 2022-10-05

Family

ID=65409089

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19704797.0A Active EP3752650B1 (fr) 2018-02-16 2019-02-11 Procédé d'affinage de métal fondu faisant appel à un convertisseur

Country Status (3)

Country Link
EP (1) EP3752650B1 (fr)
ES (1) ES2934857T3 (fr)
WO (1) WO2019158479A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102020215076A1 (de) 2020-11-30 2022-06-02 Sms Group Gmbh Verfahren zur Behandlung von Metallschmelzen und/oder Schlacken in metallurgischen Bädern sowie metallurgische Anlage zur Behandlung von Metallschmelzen

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2029083B1 (fr) 1969-01-25 1974-02-01 Demag Ag
BE792128A (fr) * 1971-12-06 1973-03-16 Uss Eng & Consult Procede et installation pour l'affinage de l'acier
BE782186A (fr) * 1972-04-14 1972-04-28 Centre Rech Metallurgique Procede d'affinage de fonte.
US4195985A (en) * 1977-12-10 1980-04-01 Eisenwerk-Gesellschaft Maximilianshutte Mbh. Method of improvement of the heat-balance in the refining of steel
ATE5202T1 (de) 1979-12-11 1983-11-15 Eisenwerk-Gesellschaft Maximilianshuette Mbh Stahlerzeugungsverfahren.
CN102796841B (zh) * 2012-08-21 2014-05-14 东北大学 一种在顶底复吹转炉中侧吹粉粒石灰石造渣炼钢的方法

Also Published As

Publication number Publication date
EP3752650A1 (fr) 2020-12-23
ES2934857T3 (es) 2023-02-27
WO2019158479A1 (fr) 2019-08-22

Similar Documents

Publication Publication Date Title
EP0446860B1 (fr) Procédé pour la fabrication de métaux et d'alliages dans un récipient pour la réduction en bain de fusion
TWI473883B (zh) 轉爐煉鋼方法
US9580764B2 (en) Top-blowing lance and method for refining molten iron using the same
JP5644355B2 (ja) 溶銑の精錬方法
JPWO2002022891A1 (ja) 精錬剤および精錬方法
JP2018178260A (ja) 転炉製鋼方法
JP5087905B2 (ja) 溶銑の脱燐処理方法
JP5834980B2 (ja) 溶鋼の製造方法
EP3752650B1 (fr) Procédé d'affinage de métal fondu faisant appel à un convertisseur
JPH1180825A (ja) 転炉精錬用上吹きランスおよびそれによる転炉精錬方法
JP5471151B2 (ja) 転炉製鋼方法
CN109790590B (zh) 脱磷处理装置及使用了该装置的铁液的脱磷方法
Aleksashin et al. Creation and growth of oxygen-converter steelmaking
KR20140053195A (ko) 고로 용선 등의 액상 용금의 탈린 방법 및 장치
JP2003239009A (ja) 溶銑の脱りん精錬方法
JP3711835B2 (ja) 溶銑脱燐用の焼結剤および溶銑の脱燐方法
JP3333339B2 (ja) 脱炭滓をリサイクルする転炉製鋼法
JP7400845B2 (ja) 溶鉄の精錬方法
JP2019090078A (ja) 吹き込み用浸漬ランス及び溶融鉄の精錬方法
JP3339982B2 (ja) 転炉製鋼法
JP6327298B2 (ja) 溶銑の精錬方法
JPH1121610A (ja) ガス吹き用ランス及び転炉型精錬炉の操業方法
JPH032312A (ja) 低燐銑の製造方法
JPH10176211A (ja) 金属精錬時のダスト逸散抑制方法及び装置
JPH03111507A (ja) 鉄系合金溶湯の製造法および装置

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20200916

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20220524

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1522785

Country of ref document: AT

Kind code of ref document: T

Effective date: 20221015

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602019020264

Country of ref document: DE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20221005

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2934857

Country of ref document: ES

Kind code of ref document: T3

Effective date: 20230227

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230206

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230105

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230205

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230106

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602019020264

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

REG Reference to a national code

Ref country code: AT

Ref legal event code: UEP

Ref document number: 1522785

Country of ref document: AT

Kind code of ref document: T

Effective date: 20221005

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20230707

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

Ref country code: AL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

26N No opposition filed

Effective date: 20230706

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20230228

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20230211

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230211

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230228

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230228

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20221005

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230211

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230211

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230211

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230228

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20230228

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 20240220

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20240219

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20240228

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20240328

Year of fee payment: 6