US20180371562A1 - Method for production of iron-silicon-aluminum alloys and their use - Google Patents
Method for production of iron-silicon-aluminum alloys and their use Download PDFInfo
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- US20180371562A1 US20180371562A1 US15/563,038 US201615563038A US2018371562A1 US 20180371562 A1 US20180371562 A1 US 20180371562A1 US 201615563038 A US201615563038 A US 201615563038A US 2018371562 A1 US2018371562 A1 US 2018371562A1
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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
- C21C5/5264—Manufacture of alloyed steels including ferro-alloys
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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
- C21C5/527—Charging of the electric 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0025—Adding carbon material
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C27/00—Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
- C22C27/06—Alloys based on chromium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C28/00—Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C35/00—Master alloys for iron or steel
- C22C35/005—Master alloys for iron or steel based on iron, e.g. ferro-alloys
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
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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 invention pertains to a method for producing of ferro-silicon-aluminum master alloys
- Ferrosilicon is a master alloy which, in particular, is used for steel and cast iron production, if appropriate together with other materials such as aluminum. Density and melting point of ferrosilicon significantly depend on the content of silicon. The higher the silicon content (mass %) the lower is its density. Generally, for doping of steel alloys standard ferrosilicon alloys are used such as FeSi 45, FeSi 65 and FeSi 75. Said master alloys belong way back to the proven initial materials for reducing and doping of steel alloys. Subject to the required quality of the alloyed or reduced steel one more doping element—aluminum—is added to the melt.
- DE 22 23 974 B2 describes a method of producing a doping alloy for reducing and doping of steel which uses a carbonaceous rock with 40 to 50 mass % ash content, 15 to 25 mass % volatile matter, 15 to 25 mass % combined carbon and 2 to 6 mass % sulfur, with calorific capacity of 1.500 to 2.000 kcal/kg as original stock for melting it into a carbon alloy, containing of 25-50 mass % Si, 10-40 mass. % aluminum, 2-10 mass. % of calcium, 0.5-2.5 mass. % of titanium, balance iron and subject to technical specifications various admixtures, as well as micro-admixtures of vanadium and boron if required.
- RU 2251586 C2 discloses the method of producing of ferro-silicon-aluminum alloys using carbonaceous rock with 15-35% carbon, as a silicon-aluminum containing material, with additional charging of coke and/or quartzite. By this way smelting of an aluminum-silicon alloy with aluminum content of 5 to 35% is carried out.
- EP 2 295 614 B1 describes an alloy for reducing and doping of steel with the following composition (mass-%):
- Silicon 45-63 Aluminum 10-25 Calcium 1-10 Barium 1-10 Vanadium 0.3-5 Titanium 1-10 Carbon 0.1-1 Balance - iron and admixtures.
- EA 201100824 A1 describes a method of smelting ferro-silicon-aluminum alloys. Carbonaceous rock, quartzite, metal scrap and wood chips are used as raw materials. The charge materials are sieved to ⁇ 20 mm size, whereby 75% thereof is charged onto the furnace peripherals.
- UA 6198 U describes a method of production of complex deoxidizers (reducers), in particular, ferro-silicon-aluminum alloys. These reducers are used preferably for dead-melted and rimming steels (for steel melting). The raw material for this method is metal scrap.
- CN 102839257 A discloses a FeSiAl based reducer used for steel production and having the following composition (mass.-%): 48-54% Al, 18-22% Si, 0.06-0.6% C, 0.006-0.05% S, 0.01-0.05% P, 0.17-0.6% Cu, balance—Fe.
- a similar alloy is described in CN 102839292 A having the following composition: (mass.-%): 20-30% Al, 45-55% Si, 22-28% Fe. Following elements can be present as admixtures: ⁇ 0.008% C, ⁇ 0.02% P, ⁇ 0.02% S, ⁇ 0.05% Cu, ⁇ 0.005% Ti, ⁇ 1.0% Mn, ⁇ 0.05% N.
- the object of the present invention is to provide for an efficient low-cost production of the FeSIAI master alloy out of simple and cheap raw materials without carbide forming in the melt during the melting process.
- the charge is to be mixed and homogenized preferably outside the melting furnace, whereby is to be loaded cone up into the melting furnace with S ⁇ derberg electrodes and then the FeSiAl alloy is being smelted.
- the claimed method allows to avoid the use of coke.
- iron-bearing material it is possible to prevent efficiently an undesirable formation of silicon carbides in the melt or considerably decrease it to a minimum.
- the carbide forming a monolithic dense master alloy is being received which can be used for deoxidation and doping of steel as well as for reducing of magnesium.
- Preparation of the carbonaceous rock is carried out, e.g. in jaw or rolling crushers, as well as similar mills. Specifically it is preferable to use grain sizes between 20 mm and 80 mm to be charged into the melting furnace.
- the carbonaceous rock is a low caloric high-ash layer between the coal layers.
- Carbonaceous rock in different deposits has different qualitative attributes and contents.
- the charged carbonaceous rock with ash content of >50% to ⁇ 65% can contain, i.a. the following chemical composition in the mineral part (ash):
- quartzite can be added or like carbonaceous rock crushed in an adequate mill whereas the preferred grain sizes are from 25 mm to 60 mm.
- quartzite consists of 97-98% SiO 2 and 1-2% Al 2 O 3 .
- Iron turnings, burning scale and iron-bearing oxides in the form of hematite and various iron ores and concentrates can serve as iron-bearing material. Preferred are iron turnings.
- Iron turnings are added in sizes 5 to 50 mm. Iron turnings can be at least partially oxidized whereas the film oxide thickness should not exceed 0.7 mm. Iron turnings can originate from common wastes of metalworking productions, e.g. milling machines, cutters, etc. Hence turnings can be considered as small sized iron fragments preferably with large oxidizable surface.
- Grain size is preferred from 50 mm to 100 mm.
- wood chips with >50% volatiles are added to the primary material, if needed.
- wood chips e.g. a high-volatile coal is used it has to have more than 40% of volatile matters.
- coke is not used as a primary material. Coke has not enough or has no volatile matters at all and it does not facilitate sufficient porosity of the furnace charge. In case of wood chips or high-volatile coal this is different because they have high percentage of volatile matters.
- the main raw materials carbonaceous rock, quartzite and iron-bearing material
- the main raw materials are being stored separately in hoppers. Should the need arise to add wood chips or high-volatile coal they are also stored in separate hoppers.
- the raw stock—carbonaceous rock, quartzite and iron turnings, and, if required, wood chips or high-volatile coal are mixed in a defined share proportion preferably outside the melting furnace and are charged to the melting furnace preferably equipped with S ⁇ derberg electrodes.
- the preferred product should be a FeSiAl master alloys with the following composition (mass-%):
- An equipment operating as per the claimed method consists of a melting furnace with at least one S ⁇ derberg electrode, various hoppers for storage of, at least, carbonaceous rock containing Si and Al oxides, quartzite, and also iron-bearing materials, if needed hoppers for wood chips or high-volatile coal, if needed preparation and crushing units at least for carbonaceous rock and if necessary for quartzite, mixing and dosing devices for charging mixture, and feeder units for feeding specifically homogeneous mixed charging material around the furnace electrodes.
- the furnace is equipped with several S ⁇ derberg electrodes, thus, in particular, the mixed homogeneous charge material is loaded cone-up wise around the electrode(s).
- special charging tubes located around the electrode(s). If the desirable conical form is not reached by common furnace charge feeding, special mechanical scrapers are used.
- the smelted FeSiAl material can be advantageously used for steel deoxidizing and doping.
- FeSiAl alloy for production of various refined grades of ferroalloys.
- Table 1 a shows examples of the molten FeSiAl master alloys which could be used for steel production.
- Table 1 b shows examples of consumption of quartzite and iron per 1 ton of FeSiAl alloy.
- Total iron content percentage consists of:
- a thin slag layer as a rule ⁇ 3.5 g/cm 3 , lies on the melt during the steel production.
- the addition of the iron turnings is of considerable technical importance for reaching the assigned density of each FeSiAl alloy as per Table 1a.
- the ratio of Fe total/Fe from iron turnings should be between 1.1 and 1.35, more specific between 1.2 and 1.3.
- Aluminum has a density of 2.2 g/cm 3 . It can happen in traditional combinations of FeSi+Al that aluminum does not penetrate into the steel volume and floats on the surface of the steelmaking slag. Such cannot happen to the FeSiAl alloy as the density increases by virtue of addition of iron turnings.
- Table 2a shows examples of FeSiAl alloys which can be used in magnesium production.
- Table 2b shows examples of consumption of quartzite and iron per 3 tons of carbonaceous rock.
- iron-bearing materials more specifically iron turnings in combination with the carbonaceous rock with high electric resistance more specifically 10 ⁇ 6 ⁇ to 10 ⁇ 1 ⁇ , and also quartzite, if necessary with addition of wood chips or high-volatile coal for the first time ever gives the chance to considerably reduce formation of silicon carbides during smelting FeSiAl alloys.
- purposeful addition of iron turnings increases the density of the melted FeSiAl master alloy so that can be reached the already described advantages of application of this master alloy in the production of steel and magnesium.
- the FeSiAl alloy produced under the claimed method substitutes the above mentioned alloys FeSi75 (+Al) and FeSi65 (+Al).
- the content of iron turnings amounts to 5 to 20% of the total mass of the primary materials.
- the best way is to add iron turnings with a big surface, thus the length of the coils chips may be up to 50-60 mm.
- the excess of the iron-bearing material decreases the concentration of basic elements—aluminum and silicon, and its lack leads to undesirable carbide forming in the melt and the master alloy melting process is impaired.
- the grain size of the furnace charge for carbonaceous rock and quartzite has to be >20-80 mm.
- the known process employs a melting furnace equipped with so called S ⁇ derberg electrodes (made of carbon and steel casing). Carbon is slowly reacting with the loaded furnace charge and is partially acting as deoxidizer. Iron in a very small quantity is converted from the electrode casing into the master alloy melt.
- oxide scale hematite, iron ore and concentrates instead of iron turnings but these materials do not prevent carbide forming as efficient as iron turnings.
- Another advantage is the fact that application of the object of invention allows to meet the different customers' requirements. So for instance, if required, it is possible to add to the furnace charge and to melt other primary oxide elements either single or combined such as barium, vanadium, calcium, etc. in form of ores or similar.
- FIGS. 1 to 3 Diagram of handling and processing of raw materials, carbonaceous rock, quartzite and iron turnings
- FIGS. 4 and 5 Diagrams of the melting furnace with several electrodes in different views.
- FIGS. 1-3 show the diagrams of handling and processing of raw materials, carbonaceous rock, quartzite and iron turnings
- FIGS. 1 and 2 are constructed similarly, thus FIG. 1 represents crushing and screening of carbonaceous rock and FIG. 2 the same of quartzite.
- the supplied carbonaceous rock 1 is being fed to the bin (hopper) 2 connected to a vibration feeder 3 or a similar device.
- the carbonaceous rock 1 gets into the crusher 5 , for example a jaw crusher.
- the crushed carbonaceous rock 1 is being screened with a screen 6 to grain sizes 0 to 20 mm and >20 to 80 mm. Grain size >20 to 80 mm is further being used in the furnace charge.
- FIG. 2 represents handling of quartzite 7 which is also being fed into bin (hopper) 8 .
- quartzite is transported to the crusher unit 11 , another jaw crusher, if required, and then is being screened through screen 12 to grain sizes 0 to 25 mm, as well as >25 to 60 mm. Size >25 to 60 mm is being further used for production. If quartzite 7 is not crushed/screened on-site it can be delivered already crushed.
- the respective mixture (carbonaceous rock >20 to 80 mm, quartzite >25 to 60 mm) is being fed via conveyors to hoppers 13 , 14 ( FIG. 3 ).
- Another hopper 15 contains also required primary material—iron-turnings 15 a with size between 5 and 100 mm, preferably 5 to 50 mm.
- iron-turnings 15 a with size between 5 and 100 mm, preferably 5 to 50 mm.
- a dosing strain-gauge weigher 16 , 17 , 18 the preset portions of carbonaceous rock 1 (hopper 13 ), quartzite 7 (hopper 14 ), as well as iron turnings 15 a (hopper 15 ) are being transported to a belt conveyor 19 , whereby the primary materials 1 , 7 , 15 a are being homogenized.
- another hopper B can be fed with wood chips H, size 50-100 mm, which is admixed to the charge consisting of carbonaceous rock 1 , quartzite 7 and iron turnings 15 a .
- wood chips H size 50-100 mm, which is admixed to the charge consisting of carbonaceous rock 1 , quartzite 7 and iron turnings 15 a .
- high-volatile coal instead of wood chips H.
- the prepared homogenized furnace charge material consisting of carbonaceous rock 1 , quartzite 7 and iron turnings 15 a (if required wood chips H) is being discharged into the furnace (not shown here). If necessary further homogenization steps like screw mixing or similar can be conducted on the way to the furnace (which is not shown here).
- FIGS. 4 and 5 represent a simplified execution of the melting furnace 23 containing several S ⁇ derberg electrodes 21 .
- the arrows designate directions of discharging of the homogenized furnace charge consisting of carbonaceous rock 1 , quartzite 7 and iron turnings 15 a and if required wood chips H loaded in the only in the designated conical form 22 around the electrodes 21 . If the conical form is impossible to reach, special mechanical auxiliary devices such as scrapers, etc. come to action in order to achieve this conical form.
- Carbonaceous raw material (high-ash coal with ash content 45-50%, carbonaceous rock with ash content 55-65%) is characterized through different content of ash, volatiles and humidity.
- one batch of carbonaceous raw material may contain lumps with different ash content. Therefore it is very important to blend the composition of the supplied batch of the carbonaceous raw material. This can be achieved through its thorough mixing during crushing and screening and also during its storage.
- Quartzite is being delivered already screened.
- the effective screen size is 25-60 mm.
- Iron turnings are being delivered crushed with 5-50 mm screen size. 50-100 mm oversize should not exceed 10%. The iron turnings can be oxidized. Oxide film thickness should not exceed 0.7 mm.
- the unit for furnace charge handling consists of a standard set of a jaw crusher and a screen—the crushing and screening unit (CSU).
- the set contains a bin (hopper) with a vibration feeder in which a pay-loader loads the carbonaceous stock. And the raw materials are transported to the bin (hopper) from different parts of the heap. From the bin (hopper) the raw materials are moved proportionally and uniformly to the crusher with 100 mm distance between the crusher jaws. After crushing the carbonaceous stock is transported to the screen having a mesh of 20 mm where the raw materials are screened into two sizes of 0 to 20 mm and >20 to 80 mm. Size >20 to 80 mm is the effective size needed for the production and is being stored.
- Weighing is carried out with the use of common batching units consisting of a 20-60 m 3 dispensing bin (hopper), a vibration feeder, tensometric balance of strip or bin type, reversible-shuttle belt.
- There should be at least three batching units for the carbonaceous stock 1-2 units for the quartzite and 1 unit for the iron turnings.
- the three batching units for the carbonaceous stock are designated for batching different batches with various ash contents. Hence it is possible to mix in different proportions the carbonaceous material of 45% and 65% ash content or coal with 30% ash content and carbonaceous rock with 65% ash content thus obtaining the required ash content needed to smelt one or another alloy grade.
- the basic batching unit is one of the weighing bins (hoppers) for carbonaceous raw material depending on the speed with which other raw materials are transported for weighing. After weighing all raw materials are fed to one reversible-shuttle belt. The raw material is placed layer-wise on it. Thereby is reached a uniform distribution of the carbonaceous raw material, the quartzite and the iron turnings. Further the charge mix is discharged from the reversible-shuttle belt to the inclined belt conveyer which feeds the charge mix to the melting shop on a mark with the furnace bins (hoppers).
- the charge gets from the inclined belt conveyer through a hopper mechanism to a running inclined belt conveyor on the furnace bins (hoppers) mark over the furnace bath.
- the furnace bins (hoppers) are sequentially fed by furnace charge.
- the charge from the furnace bins (hoppers) is discharged into the furnace bath through charging tubes, if necessary, and depends on the speed of its smelting in the furnace bath.
- the ferrosilicon aluminum smelting process can be divided into three intervals depending on the temperature and preferential behavior of the different reactions.
- SiO+C solid Si liquid +CO (4)
- SiO 2 solid +CO ⁇ SiO ⁇ +CO 2 (7)
- Al 2 O+C solid 2Al liquid +CO (8)
- SiO gas +SiC solid 2Si liquid +CO (10)
- a specific feature of this temperature interval/range is the formation of aluminum carbide which is easily neutralized in surplus of silica with formation of ferrosilicon aluminum.
- This example presents a ferrosilicon aluminum alloy in the charge of which was added manganese as oxide material, besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- This example presents a ferrosilicon aluminum alloy in the charge of which was added barium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- This example presents a ferrosilicon aluminum alloy in the charge of which was added calcium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- This example presents a ferrosilicon aluminum alloy in the charge of which was added chrome as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- the following example presents a ferrosilicon aluminum alloy in the charge of which was added vanadium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- V 2 O 5 Vanadium pentoxide briquettes 0.15 tons, size 10-30 mm
- This example presents a ferrosilicon aluminum alloy in the charge of which was added titanium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- This example presents a refined ferrochrome (FeCr) alloy in the charge of which besides chrome ore and lime was added FeSiAl alloy as reducing material.
- the following example presents the process of production of one ton magnesium metal with the use of FeSiAl alloy as a reducing agent.
- the beginning of the process includes briquetting of crushed doloma (calcined lime dolomite) and FeSiAl with size 0.1-5 mm.
- the reducing process is running for 8 hours in a retort at 1,200° C. and vacuum 10 ⁇ 2 atm.
- Doloma 1.7 ton, size 0.1 to 2.0 mm
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Abstract
Method of producing FeSiAI alloys wherein a carbonaceous rock with an ash content >50% to <65%, is being mixed with quartzite, iron-bearing material, and wood chips, if required, high volatile coal, in a preset ratio of the charge components and the homogenized charge material is being loaded into a melting furnace for melting of FeSiAI alloy, the charged carbonaceous rock can contain i.a. the following chemical composition in the mineral part (ash): Fe2O3 1.5-4.5% SiO2 55-65% Al2O3 25-35%, especially 32-34% CaO 0.3-3% MgO 0.3-2% TiO2 up to 1.5 S>0-0.4%, especially 0.01-0.06% P 0.01-0.05%
Description
- The invention pertains to a method for producing of ferro-silicon-aluminum master alloys
- Ferrosilicon is a master alloy which, in particular, is used for steel and cast iron production, if appropriate together with other materials such as aluminum. Density and melting point of ferrosilicon significantly depend on the content of silicon. The higher the silicon content (mass %) the lower is its density. Generally, for doping of steel alloys standard ferrosilicon alloys are used such as FeSi 45, FeSi 65 and FeSi 75. Said master alloys belong way back to the proven initial materials for reducing and doping of steel alloys. Subject to the required quality of the alloyed or reduced steel one more doping element—aluminum—is added to the melt.
- DE 22 23 974 B2 describes a method of producing a doping alloy for reducing and doping of steel which uses a carbonaceous rock with 40 to 50 mass % ash content, 15 to 25 mass % volatile matter, 15 to 25 mass % combined carbon and 2 to 6 mass % sulfur, with calorific capacity of 1.500 to 2.000 kcal/kg as original stock for melting it into a carbon alloy, containing of 25-50 mass % Si, 10-40 mass. % aluminum, 2-10 mass. % of calcium, 0.5-2.5 mass. % of titanium, balance iron and subject to technical specifications various admixtures, as well as micro-admixtures of vanadium and boron if required.
- It is known in the prior art (DE 28 53 007 A1) the method of producing silicon containing ferroalloys which consists of pelletizing the mixture of a carbonaceous reducing agent and leading element ore of the resulting alloy with addition of quartzite, of received charge material into the melting furnace and in the following continuous single-stage recovery of the resulting alloy elements.
- RU 2251586 C2 discloses the method of producing of ferro-silicon-aluminum alloys using carbonaceous rock with 15-35% carbon, as a silicon-aluminum containing material, with additional charging of coke and/or quartzite. By this way smelting of an aluminum-silicon alloy with aluminum content of 5 to 35% is carried out.
- EP 2 295 614 B1 describes an alloy for reducing and doping of steel with the following composition (mass-%):
-
Silicon 45-63 Aluminum 10-25 Calcium 1-10 Barium 1-10 Vanadium 0.3-5 Titanium 1-10 Carbon 0.1-1 Balance - iron and admixtures. - EA 201100824 A1 describes a method of smelting ferro-silicon-aluminum alloys. Carbonaceous rock, quartzite, metal scrap and wood chips are used as raw materials. The charge materials are sieved to <20 mm size, whereby 75% thereof is charged onto the furnace peripherals.
- UA 6198 U describes a method of production of complex deoxidizers (reducers), in particular, ferro-silicon-aluminum alloys. These reducers are used preferably for dead-melted and rimming steels (for steel melting). The raw material for this method is metal scrap.
- CN 102839257 A discloses a FeSiAl based reducer used for steel production and having the following composition (mass.-%): 48-54% Al, 18-22% Si, 0.06-0.6% C, 0.006-0.05% S, 0.01-0.05% P, 0.17-0.6% Cu, balance—Fe.
- A similar alloy is described in CN 102839292 A having the following composition: (mass.-%): 20-30% Al, 45-55% Si, 22-28% Fe. Following elements can be present as admixtures: <0.008% C, <0.02% P, <0.02% S, <0.05% Cu, <0.005% Ti, <1.0% Mn, <0.05% N.
- The known prior art reflecting the process of FeSiAl production is distinct in high carbide forming in slag which is negatively affecting FeSiAl production. In the event the melting furnace becomes impracticable or must be picked out for the next operation which is extremely expensive.
- The object of the present invention is to provide for an efficient low-cost production of the FeSIAI master alloy out of simple and cheap raw materials without carbide forming in the melt during the melting process.
- Besides, there should be offered an opportunity to replace alloys for reducing and doping of steel, such as ferrosilicon and aluminum which earlier were applied separately.
- This objective is solved by Method of producing FeSiAl alloys wherein a carbonaceous rock with an ash content >50% to <65%, is being mixed with quartzite, iron-bearing material, and wood chips, if required, high volatile coal, in a preset ratio of the charge components and the homogenized charge material is being loaded into a melting furnace for melting of FeSiAl alloy, the charged carbonaceous rock can contain i.a. the following chemical composition in the mineral part (ash):
-
Fe2O3 1.5-4.5% Si02 55-65% Al2O3 25-35%, especially 32-34% CaO 0.3-3% MgO 0.3-2% TiO2 up to 1.5% S >0-0.4%, especially 0.01-0.06% P 0.01-0.05% - Advantageous improvements of the claimed method can be examined in the correspondent dependent method claims.
- The charge is to be mixed and homogenized preferably outside the melting furnace, whereby is to be loaded cone up into the melting furnace with Søderberg electrodes and then the FeSiAl alloy is being smelted.
- As opposed to the prior art this method enables to produce the FeSiAl master alloys using cheap raw materials (carbonaceous rock, quartzite, iron-bearing material), replacing at the same time common ferrosilicon alloys and addition of aluminum if required.
- Distinct from the known prior art the claimed method allows to avoid the use of coke. By a calculated addition of iron-bearing material it is possible to prevent efficiently an undesirable formation of silicon carbides in the melt or considerably decrease it to a minimum. By virtue of the ultimate fall-off of the carbide forming a monolithic dense master alloy is being received which can be used for deoxidation and doping of steel as well as for reducing of magnesium.
- Preparation of the carbonaceous rock is carried out, e.g. in jaw or rolling crushers, as well as similar mills. Specifically it is preferable to use grain sizes between 20 mm and 80 mm to be charged into the melting furnace.
- Under the carbonaceous rock the specialists understand a coal-bearing rock with 50% to 65% ash content. The carbonaceous rock is a low caloric high-ash layer between the coal layers.
- Carbonaceous rock in different deposits has different qualitative attributes and contents. For the claimed method it is preferable to use carbonaceous rock with higher electrical resistance of the rock. Preferred is the range of resistance between 10−6Ω and 10−1Ω. The higher the electrical resistance of the rock the better is it to control the furnace temperature.
- The charged carbonaceous rock with ash content of >50% to <65% can contain, i.a. the following chemical composition in the mineral part (ash):
-
Fe2O3 1.5-4.5% SiO2 55-65% Al2O3 25 05-35% CaO 0.3-3% MgO 0.3-2% TiO2 up to 1.5% S 0.01-0.06% P 0.01-0.05% - If appropriate quartzite can be added or like carbonaceous rock crushed in an adequate mill whereas the preferred grain sizes are from 25 mm to 60 mm. Usually quartzite consists of 97-98% SiO2 and 1-2% Al2O3.
- Iron turnings, burning scale and iron-bearing oxides in the form of hematite and various iron ores and concentrates can serve as iron-bearing material. Preferred are iron turnings.
- Iron turnings are added in
sizes 5 to 50 mm. Iron turnings can be at least partially oxidized whereas the film oxide thickness should not exceed 0.7 mm. Iron turnings can originate from common wastes of metalworking productions, e.g. milling machines, cutters, etc. Hence turnings can be considered as small sized iron fragments preferably with large oxidizable surface. - As appropriate a certain portion of wood chips or high-volatile coal can be added to the charge mixture. Grain size is preferred from 50 mm to 100 mm.
- Similarly wood chips with >50% volatiles are added to the primary material, if needed.
- If instead of wood chips, e.g. a high-volatile coal is used it has to have more than 40% of volatile matters.
- As already mentioned coke is not used as a primary material. Coke has not enough or has no volatile matters at all and it does not facilitate sufficient porosity of the furnace charge. In case of wood chips or high-volatile coal this is different because they have high percentage of volatile matters.
- The main raw materials (carbonaceous rock, quartzite and iron-bearing material) with the required grain sizes are being stored separately in hoppers. Should the need arise to add wood chips or high-volatile coal they are also stored in separate hoppers.
- Based on the capacity of the melting furnace, the raw stock—carbonaceous rock, quartzite and iron turnings, and, if required, wood chips or high-volatile coal, are mixed in a defined share proportion preferably outside the melting furnace and are charged to the melting furnace preferably equipped with Søderberg electrodes.
- The preferred product should be a FeSiAl master alloys with the following composition (mass-%):
-
Si 40-85% Al >1-<40% C >0.001-<1.0% Ti 2% max Ca <1.0% P <0.05% S <0.1% Mn 0.7% max Fe balance - An equipment operating as per the claimed method consists of a melting furnace with at least one Søderberg electrode, various hoppers for storage of, at least, carbonaceous rock containing Si and Al oxides, quartzite, and also iron-bearing materials, if needed hoppers for wood chips or high-volatile coal, if needed preparation and crushing units at least for carbonaceous rock and if necessary for quartzite, mixing and dosing devices for charging mixture, and feeder units for feeding specifically homogeneous mixed charging material around the furnace electrodes.
- Advantageous improvements of the claimed equipment can be examined in the corresponding dependent claims.
- As already presented the furnace is equipped with several Søderberg electrodes, thus, in particular, the mixed homogeneous charge material is loaded cone-up wise around the electrode(s). Here are used special charging tubes located around the electrode(s). If the desirable conical form is not reached by common furnace charge feeding, special mechanical scrapers are used.
- The smelted FeSiAl material can be advantageously used for steel deoxidizing and doping.
- Alternatively, it is also possible to use another quality of FeSiAl in the process of manufacturing of magnesium alloys, e.g. as a reducing agent.
- Furthermore it is practical to use FeSiAl alloy for production of various refined grades of ferroalloys.
- Table 1 a shows examples of the molten FeSiAl master alloys which could be used for steel production.
-
TABLE 1a Alloy Grade FeSiAl 45/15 FeSiAl 55/20 FeSiAl 65/15 Silicon Si 45% 55% 65% Aluminum Al 15% 20% 15% Iron Fe 38% 23% 18% Titanium Ti 1% 1% 1% Specific density 4.5 g/cm3 4.0 g/cm3 3.8 g/cm3 *) about 1 mass-% of the total impurities Ca, P, S, Mn, Cr can be ignored - Table 1 b shows examples of consumption of quartzite and iron per 1 ton of FeSiAl alloy.
-
TABLE 1b Quantity of 2.5 t 3.15 t 2.8 t carbonaceous rock (tons) Ash content of 55% 58% 56% carbonaceous rock V = 20 W = 4 V = 18 W = 4 V = 22 W = 4 Quartzite qty. (tons) 0.5 t 0.42 t 0.9 t Fe total (tons) 0.315 t 0.158 t 0.14 t incl. Fe from 0.015 t 0.018 t 0.02 t electrodes (tons) incl. Fe turnings (tons) 0.30 t 0.14 t 0.12 t - Total iron content percentage consists of:
-
- iron ratio from carbonaceous rock
- iron ratio from iron turnings (iron turnings are cited also as iron-bearing material)
- iron ratio from melting electrodes.
- A thin slag layer, as a rule <3.5 g/cm3, lies on the melt during the steel production.
- The addition of the iron turnings is of considerable technical importance for reaching the assigned density of each FeSiAl alloy as per Table 1a. The ratio of Fe total/Fe from iron turnings should be between 1.1 and 1.35, more specific between 1.2 and 1.3.
- Due to the above indicated density FeSiAl alloys (table 1a) do not float to the surface of the steelmaking slag but rather penetrate through it thus fulfilling their mission namely: deoxidation or doping of steel.
- Aluminum has a density of 2.2 g/cm3. It can happen in traditional combinations of FeSi+Al that aluminum does not penetrate into the steel volume and floats on the surface of the steelmaking slag. Such cannot happen to the FeSiAl alloy as the density increases by virtue of addition of iron turnings.
- Table 2a shows examples of FeSiAl alloys which can be used in magnesium production.
-
TABLE 2a Alloy Type FeSiAl 75/10 FeSiAl 80/7 Silicon Si 75% 80% Aluminum Al <10% <10 % Iron Fe 13% <10% Titanium Ti <1% <1% Specific density 3.5 g/cm3 3.3 g/cm3 *) about 1 mass-% of the total impurities Ca. P, S, Mn, Cr can be ignored - Table 2b shows examples of consumption of quartzite and iron per 3 tons of carbonaceous rock.
-
TABLE 2b Alloy Grade FeSi45Al15 FeSi55Al20 Quantity of carbonaceous rock (ton) 3.0 t 3.0 t Ash content carbonaceous rock 55% 55% V = 20 W = 4 Quartzit qty (ton) 0.58 t 0.57 t Fe total, incl. 0.375 t 0.18 t Fe from electrodes (ton) 0.015 t 0.012 t Fe from iron turnings (ton) 0.36 t 0.16 t - Application of iron-bearing materials more specifically iron turnings in combination with the carbonaceous rock with high electric resistance more specifically 10−6Ω to 10−1Ω, and also quartzite, if necessary with addition of wood chips or high-volatile coal for the first time ever gives the chance to considerably reduce formation of silicon carbides during smelting FeSiAl alloys. In this case it is possible to use cheap raw materials: carbonaceous rock, quartzite and iron turnings that represents a more economical alternative to traditional raw materials FeSi+Al. In particular purposeful addition of iron turnings increases the density of the melted FeSiAl master alloy so that can be reached the already described advantages of application of this master alloy in the production of steel and magnesium.
- Contingent on the used carbonaceous rocks it may contain up to 1.5% titanium, which is not affecting the process of deoxidation and doping of steel or reduction of magnesium.
- Iron oxide (FeO) on the surface of turnings disrupts silicon carbide (SiC) and prevents the carbide forming process during the FeSiAl production.
- As already mentioned sometimes it is possible to add pre-measured amount of wood chips and alternatively high-volatile coal, thus these materials are used only as an aerator for the furnace charge in order to avoid sintering on the furnace mouth and to achieve a uniform emission of the reaction gases.
- Nowadays in the world market there exist, i.a., standard alloys of FeSi65 and FeSi75 which are universally used combined with addition of aluminum in the production of steel or magnesium.
- The FeSiAl alloy produced under the claimed method substitutes the above mentioned alloys FeSi75 (+Al) and FeSi65 (+Al).
- As a result of the desired prevention of carbide forming during the FeSiAl smelting a dense alloy as master alloy is being made which contributes to better quality of the respective steel and magnesium grades.
- Depending on the subsequent compositions of steel and magnesium the content of iron turnings amounts to 5 to 20% of the total mass of the primary materials. The best way is to add iron turnings with a big surface, thus the length of the coils chips may be up to 50-60 mm.
- The excess of the iron-bearing material decreases the concentration of basic elements—aluminum and silicon, and its lack leads to undesirable carbide forming in the melt and the master alloy melting process is impaired.
- The grain size of the furnace charge for carbonaceous rock and quartzite has to be >20-80 mm.
- The known process employs a melting furnace equipped with so called Søderberg electrodes (made of carbon and steel casing). Carbon is slowly reacting with the loaded furnace charge and is partially acting as deoxidizer. Iron in a very small quantity is converted from the electrode casing into the master alloy melt.
- If needed, it is possible to use oxide scale, hematite, iron ore and concentrates instead of iron turnings but these materials do not prevent carbide forming as efficient as iron turnings. Another advantage is the fact that application of the object of invention allows to meet the different customers' requirements. So for instance, if required, it is possible to add to the furnace charge and to melt other primary oxide elements either single or combined such as barium, vanadium, calcium, etc. in form of ores or similar.
- The below table indicates oxide components to be added if required:
-
Ca 0.05-7.0% Ba 1.5-15% V 0.5-10% Ti 0.05-10% Cr 5-20% Mn 5-20% - Examples of embodiments of the invention are presented and described as follows:
-
FIGS. 1 to 3 Diagram of handling and processing of raw materials, carbonaceous rock, quartzite and iron turnings; -
FIGS. 4 and 5 Diagrams of the melting furnace with several electrodes in different views. -
FIGS. 1-3 show the diagrams of handling and processing of raw materials, carbonaceous rock, quartzite and iron turnings; -
FIGS. 1 and 2 are constructed similarly, thusFIG. 1 represents crushing and screening of carbonaceous rock andFIG. 2 the same of quartzite. - The supplied carbonaceous rock 1 is being fed to the bin (hopper) 2 connected to a
vibration feeder 3 or a similar device. Through the only indicated conveyor 4 the carbonaceous rock 1 gets into thecrusher 5, for example a jaw crusher. In this way the crushed carbonaceous rock 1 is being screened with ascreen 6 to grain sizes 0 to 20 mm and >20 to 80 mm. Grain size >20 to 80 mm is further being used in the furnace charge. -
FIG. 2 represents handling ofquartzite 7 which is also being fed into bin (hopper) 8. From the vibratingfeeder 9 andconveyor belt 10 quartzite is transported to thecrusher unit 11, another jaw crusher, if required, and then is being screened throughscreen 12 to grain sizes 0 to 25 mm, as well as >25 to 60 mm. Size >25 to 60 mm is being further used for production. Ifquartzite 7 is not crushed/screened on-site it can be delivered already crushed. - In further process stages the respective mixture (carbonaceous rock >20 to 80 mm, quartzite >25 to 60 mm) is being fed via conveyors to
hoppers 13, 14 (FIG. 3 ). - Another hopper 15 contains also required primary material—iron-
turnings 15 a with size between 5 and 100 mm, preferably 5 to 50 mm. Through a dosing strain-gauge weigher iron turnings 15 a (hopper 15) are being transported to abelt conveyor 19, whereby theprimary materials - If required another hopper B can be fed with wood chips H, size 50-100 mm, which is admixed to the charge consisting of carbonaceous rock 1,
quartzite 7 andiron turnings 15 a. As described earlier it is possible to use high-volatile coal instead of wood chips H. - Via next transport equipment/
device 20, shown here as a belt conveyor, the prepared homogenized furnace charge material consisting of carbonaceous rock 1,quartzite 7 andiron turnings 15 a (if required wood chips H) is being discharged into the furnace (not shown here). If necessary further homogenization steps like screw mixing or similar can be conducted on the way to the furnace (which is not shown here). -
FIGS. 4 and 5 represent a simplified execution of the meltingfurnace 23 containingseveral Søderberg electrodes 21. The arrows designate directions of discharging of the homogenized furnace charge consisting of carbonaceous rock 1,quartzite 7 andiron turnings 15 a and if required wood chips H loaded in the only in the designatedconical form 22 around theelectrodes 21. If the conical form is impossible to reach, special mechanical auxiliary devices such as scrapers, etc. come to action in order to achieve this conical form. - Further the object of the invention is described more detailed in examples:
- For example: the following homogenized furnace charge materials are used to produce FeSiAl 65/15:
- A. Carbonaceous rock, 3 tons, ash content 50-55%, grain size >20-80 mm Ash chemical analysis
-
SiO2 55-60% Fe2O3 1.5-4.5% Al2O3 32-34% CaO 0.3-3.0% TiO2 0.8-1.2% S 0.02-0.04% P 0.01-0.05% - B. Quartzite, 0.4-1.3 tons, grain size 25-60 mm
-
SiO2 >97% Al2O3 1.0% Fe2O3 + CaO + MgO + P2O3 ≈ 2% - C. Iron Turnings >0-0.5%
- Raw Material
- Carbonaceous raw material (high-ash coal with ash content 45-50%, carbonaceous rock with ash content 55-65%) is characterized through different content of ash, volatiles and humidity. For example one batch of carbonaceous raw material may contain lumps with different ash content. Therefore it is very important to blend the composition of the supplied batch of the carbonaceous raw material. This can be achieved through its thorough mixing during crushing and screening and also during its storage.
- Quartzite is being delivered already screened. The effective screen size is 25-60 mm.
- Iron turnings are being delivered crushed with 5-50 mm screen size. 50-100 mm oversize should not exceed 10%. The iron turnings can be oxidized. Oxide film thickness should not exceed 0.7 mm.
- 1.1. Crushing and Screening of Raw Materials
- The unit for furnace charge handling consists of a standard set of a jaw crusher and a screen—the crushing and screening unit (CSU). The set contains a bin (hopper) with a vibration feeder in which a pay-loader loads the carbonaceous stock. And the raw materials are transported to the bin (hopper) from different parts of the heap. From the bin (hopper) the raw materials are moved proportionally and uniformly to the crusher with 100 mm distance between the crusher jaws. After crushing the carbonaceous stock is transported to the screen having a mesh of 20 mm where the raw materials are screened into two sizes of 0 to 20 mm and >20 to 80 mm. Size >20 to 80 mm is the effective size needed for the production and is being stored.
- 1.2. Storage of the Carbonaceous Stock
- After crushing the effective size of the carbonaceous raw material is stored in even layers on the whole defined surface. This is achieved by using a traversing conveyor with a splitter or directly by a pay-loader. Thus is obtained a pile of 3-4 layers of the carbonaceous stock. The feeding of the carbonaceous stock to the weighing bin (hopper) is done from the end of the pile while the layers are being mixed.
- In this way mixing and blending of the raw material batch is made during crushing, piling and charging of the carbonaceous stock into the weighing bin (hopper).
- 1.3. Weighing of Raw Materials
- Weighing is carried out with the use of common batching units consisting of a 20-60 m3 dispensing bin (hopper), a vibration feeder, tensometric balance of strip or bin type, reversible-shuttle belt. There should be at least three batching units for the carbonaceous stock, 1-2 units for the quartzite and 1 unit for the iron turnings. The three batching units for the carbonaceous stock are designated for batching different batches with various ash contents. Hence it is possible to mix in different proportions the carbonaceous material of 45% and 65% ash content or coal with 30% ash content and carbonaceous rock with 65% ash content thus obtaining the required ash content needed to smelt one or another alloy grade.
- The basic batching unit is one of the weighing bins (hoppers) for carbonaceous raw material depending on the speed with which other raw materials are transported for weighing. After weighing all raw materials are fed to one reversible-shuttle belt. The raw material is placed layer-wise on it. Thereby is reached a uniform distribution of the carbonaceous raw material, the quartzite and the iron turnings. Further the charge mix is discharged from the reversible-shuttle belt to the inclined belt conveyer which feeds the charge mix to the melting shop on a mark with the furnace bins (hoppers).
- 1.4. Furnace Bins (Hoppers) and Furnace Bath Charging
- The charge gets from the inclined belt conveyer through a hopper mechanism to a running inclined belt conveyor on the furnace bins (hoppers) mark over the furnace bath. The furnace bins (hoppers) are sequentially fed by furnace charge. The charge from the furnace bins (hoppers) is discharged into the furnace bath through charging tubes, if necessary, and depends on the speed of its smelting in the furnace bath. There are ten charging tubes, i.e. three near each electrode and one charging tube in the center between the electrodes. The charge is steadily fed to the electrodes. If required it is scraped to the electrodes with special steel scrapers (for small electric furnaces of up to 5 MVA) or with special devices for charge distribution (for electric furnaces of 10-33 MVA) to the electrodes creating 300-600 mm high charge cones around the electrodes. It improves settling of fumes of gaseous silicon (SiO) and aluminum (Al2O) suboxides.
- The ferrosilicon aluminum smelting process can be divided into three intervals depending on the temperature and preferential behavior of the different reactions.
- The temperature interval/range of T=1,400-1,500° C. is characterized by active decrease in mullite concentration in the reaction mixture. Following reactions are taking place in this temperature interval/range depending on the way of heating the charge in this temperature interval/range:
-
SiO2,solid+Csolid={SiO}+CO (1) -
SiO2,solid+2Csolid+Fe=SiFe+2CO (2) -
[Si]+Csolid=SiC (3) -
SiO+Csolid=Siliquid+CO (4) -
{SiO}+2Csolid=SiCsolid+CO (5) -
SiO2 solid→SiO+½O2 (7) -
SiO2 solid+CO={SiO}+CO2 (7) -
Al2O+Csolid=2Alliquid+CO (8) - Among them the greatest product yield is only produced by the reaction leading to formation of silicon carbide. The change of its quantity in the reaction mixture is characterized by prompt burst starting from temperature >1.550° C.
- In a temperature interval/range 1,650-2,050° C. in the wake of temperature rising the following reactions start to run:
-
SiO2,solid+Siliquid=2SiO (9) -
SiOgas+SiCsolid=2Siliquid+CO (10) -
SiO2+SiC=SiO+Si+CO (11) - With further rise of temperature (above 1,800° C.) following reactions are developing:
-
2Al2O3 solid+9Csolid=Al4C3 solid+6CO (12) -
2Al4C3 solid+3SiO2=8Alliquid+3Siliquid+6CO (13) -
⅔Al2O3+2SiC+Fe=2SiFe+ 4/3AlFe+2CO (14) -
Al2O3 solid+2C=Al2O+2CO (15) -
Al2O3 solid+3C=2All+3CO (16) -
Al2O3+SiC=Al2O+SiO+CO (17) - A specific feature of this temperature interval/range is the formation of aluminum carbide which is easily neutralized in surplus of silica with formation of ferrosilicon aluminum.
- At temperatures over 2,050° C. the content of silicon carbides in the charge drops substantially and concentration of silicon and aluminum in the metal rises. Whereby the silicon carbide is mainly consumed for interaction with alumina, Si- and Al-suboxides with formation of a silicon-aluminum alloy:
-
2Al2O3+SiCsolid=4Alliquid+SiOgas+CO (18) -
Al2Ogas+SiCsolid=2Alliquid+Siliquid+CO (19) -
Alliquid→Algas (20) - But simultaneously form >2,100° C. temperature level the evaporation of aluminum increases.
- This example presents a ferrosilicon aluminum alloy in the charge of which was added manganese as oxide material, besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- FeSiAl Alloys with Manganese
- A. Carbonaceous rock 2.99 tons, size >20-80 mm
-
Ash content (on dry mass) 53.4%; Volatile matter (on dry mass) 18.3% Humidity 4.0% Ash composition: SiO2 63.2% Fe2O3 2.5% Al2O3 31.7% CaO 1.1% TiO2 0.9% MgO 0.3% S 0.018% P 0.012% - B. Quartzite—0.126 tons, size 25-60 mm
-
SiO2 97.5% Al2O3 1.0% Fe2O3 0.6% CaO 0.5% MgO 0.2% Σ (oxides P, S, Na, K, Ti) <0.2% (balance) - C. Iron turnings—0.09 tons, size 5-30 mm
-
Fetotal 98.6% Si, Al, C balance - D. Manganese ore 0.457 ton, size 10-60 mm
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Mn2O3 53.9% Fe2O3 7.9% SiO2 26.2% Al2O3 1.7% CaO 5.2% TiO2 0.1% MgO 1.0% S 0.02% P 0.02% Ignition losses 3.96% - At the end of the melting process is obtained a FeSiAl alloy with Manganese with the following average composition (mass-%):
-
Si 45.2 Al 18.8 Mn 14.6 C 0.25 Ti 0.6 Ca 1.2 P 0.01 S 0.001; Fe balance - This example presents a ferrosilicon aluminum alloy in the charge of which was added barium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- FeSiAl with Barium
- A. Carbonaceous rock 3.03 tons, size >20-80 mm
-
Ash content (on dry mass) 55.2% Volatile matter (on dry mass) 18.7% Humidity 5.1% Ash composition: SiO2 60.9% Fe2O3 2.2% Al2O3 34.2% CaO 1.5% TiO2 1.0% MgO 0.12% S 0.014% P 0.016% - B. Quartzite—0.397 tons, size 25-60 mm
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SiO2 97.3% Al2O3 1.2% Fe2O3 0.7% CaO 0.4% (MgO + TiO2 + P2O5 + S + MnO + Cr2O3) <0.4%-balance - C. Iron turnings—0.091 tons, size 5-30 mm
-
Fetotal 98.6% Si, Al, C— balance - D. Barium ore—0.306 tons, size 10-50 mm
-
BaSO4 81.3% SiO2 15.2% Fe2O3 1.4% Al2O3 0.82% CaO 1.2% MgO 0.06% P2O5 0.02% - At the end of the melting process is obtained a FeSiAl alloy with Barium with the following average composition (mass-%):
-
Si 51.3 Al 20.7 Ba 10.7 C 0.15 Ti 0.6 Ca 0.8 P 0.011 S 0.002 Fe balance - This example presents a ferrosilicon aluminum alloy in the charge of which was added calcium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- FeSiAl Alloy with Calcium
- A. Carbonaceous rock 3.17 tons, size >20-80 mm
-
Ash content (on dry mass) 55.2% Volatile matter (on dry mass) 18.7% Humidity 4.5% Ash composition: SiO2 60.9% Fe2O3 2.2% Al2O3 34.2% CaO 1.5% TiO2 1.0% MgO 0.17% S 0.014% P 0.016% - B. Quartzite—0.42 tons, size 25-60 mm
-
SiO2 97.3% Al2O3 1.2% Fe2O3 0.7% CaO 0.4% (MgO + TiO2 + P2O5 + S) <0.4% - balance - C. Iron turnings—0.11 tons, size 5-30 mm
-
Fetotal 98.6% Si, Al, C - balance. - D. Lime−0.143 tons, size 10-30 mm
-
SiO2 4.6% Fe2O3 2.5% Al2O3 1.3% CaO 86.4% MgO 4.4% P2O5 0.12% Ignition losses 0.68% - At the end of the melting process is obtained a FeSiAl alloy with Calcium with the following average composition (mass-%):
-
Si 53.2 Al 20.5 Ca 6.5 C 0.19 Ti 0.64 P 0.013 S 0.001 Fe balance - This example presents a ferrosilicon aluminum alloy in the charge of which was added chrome as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- FeSiAl Alloy with Chrome
- A. Carbonaceous rock 3.0 tons, size >20-80 mm
-
Ash content (on dry mass) 50.1% Volatile matter (on dry mass) 18.4% Humidity 4.1% Ash composition: SiO2 64.8% Fe2O3 2.6% Al2O3 30.4% CaO 0.96% TiO2 1.12% MgO 0.1% S 0.012% P 0.008% - B. Quartzite—0.455 tons, size 25-60 mm
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SiO2 97.2% Al2O3 1.0% Fe2O3 0.6% CaO 0.2% (MgO + TiO2 + P2O5 + S) <1.0% - balance - C. Iron turnings—0.1 t, size 5-30 mm
-
Fetotal 98.6% Si, Al, C balance. - D. Chrome ore 0.325 t, size 8-50 mm
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Cr2O3 47.35% FeO 13.57% SiO2 9.5% Al2O3 7.5% CaO 0.4% MgO 18.0% S 0.01% P 0.008% Ignition losses 3.66% - At the end of the melting process is obtained a FeSiAl alloy with Chrome with the following average composition (mass-%):
-
Si 52.4 Al 18.1 Cr 16.0 C 0.24 Ti 0.50 Ca 0.63 P 0.011 S 0.001 Fe balance - The following example presents a ferrosilicon aluminum alloy in the charge of which was added vanadium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- FeSiAl Alloy with Vanadium
- A. Carbonaceous rock 2.93 tons, size >20-80 mm
-
Ash content (on dry mass) 53.4% Volatile matter (on dry mass) 18.1% Humidity 4.7% Ash composition: SiO2 62.2 Fe2O3 2.6% Al2O3 32.5% CaO 1.4% TiO2 1.14% MgO 0.14 S 0.01% P 0.011% - B. Quartzite—0.54 tons, size 25-60 mm
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SiO2 97.5% Al2O3 1.2% Fe2O3 0.7% CaO 0.4% (MgO + TiO2 + P2O5 + S) <0.2% - balance - C. Iron turnings—0.118 t, size 5-30 mm
-
- Fetotal—98.6%
- Si, Al, C—balance
- D. Vanadium pentoxide briquettes (V2O5) 0.15 tons, size 10-30 mm
-
V2O5 95.0% SiO2 0.3% Fe2O3 0.5% Al2O3 0.5% CaO 0.2% K2O + Na2O 0.4% P2O5 0.09% Ignition losses 3.01%. - At the end of the melting process is obtained a FeSiAl alloy with vanadium with the following average composition (mass-%):
-
Si 54.0 Al 18.5 V 7.4 Ca 1.0 C 0.21 Ti 0.60 P 0.007 S 0.001 Fe balance. - This example presents a ferrosilicon aluminum alloy in the charge of which was added titanium as oxide material besides carbonaceous rock, quartzite and iron turnings (wooden chips if required).
- FeSiAl Alloy with Titanium
- A. Carbonaceous rock 2.88 tons, size >20-80 mm
-
Ash content (on dry mass) 53.7% Volatile matter (on dry mass) 17.5% Humidity 4.2% Ash composition: SiO2 63.5% Fe2O3 2.3% Al2O3 31.4% CaO 1.7% TiO2 0.95% MgO 0.023% S 0.011% P 0.009% (MgO + TiO2 + P2O5 + S) <0.2%-balance - B. Quartzite—0.36 tons, size 25-60 mm
-
SiO2 97.5% Al2O3 1.2% Fe2O3 0.7% CaO 0.4%. - C. Iron turnings—0.129 tons, size 5-30 mm
-
- Fetotal—98.6%
- Si Al, C—balance
- D. Rich titanium slag 0.26 tons, size 10-40 mm
-
SiO2 9.67% Fe2O3 16.8% Al2O3 3.60% TiO2 63.2% CaO 3.4% MgO 1.7% P2O5 0.008% V2O5 1.40% Humidity 1.0%. - At the end of the melting process is obtained a FeSiAl alloy with titanium with the following average composition (mass.-%):
-
Si 49.5 Al 18.7 Ti 7.7 Ca 1.4 V 0.2 C 0.22 P 0.007 S 0.001 Fe— balance. - This example presents a refined ferrochrome (FeCr) alloy in the charge of which besides chrome ore and lime was added FeSiAl alloy as reducing material.
- A. Chrome ore 2.29 t, size 5-15 mm
-
Cr2O3 49.5% FeO— 11.2% SiO2 8.6% Al2O3 7.5% CaO 0.22% MgO 18.5% S— 0.023% P 0.007% Ignition losses 4.45% - B. Lime—1.3 ton, size 10-25 mm
-
SiO2 4.6% Fe2O3 0.3% Al2O3 0.5% CaO 90.1% MgO 2.4%; P2O5 0.1% Ignition losses 2.0% - C. FeSiAl—0.5 ton, size 5-10 mm
-
Si 58.6 Al 19.2 Fe 20.32 Ca 0.74 Ti 0.85 C 0.28 P 0.01 S 0.001 - At the end of the melting process is obtained a FeCr alloy with the following average composition (mass-%):
-
Cr 71.3 Si 1.45 Al 0.20 C 0.08 P 0.01 S 002 Fe balance. - The following example presents the process of production of one ton magnesium metal with the use of FeSiAl alloy as a reducing agent. The beginning of the process includes briquetting of crushed doloma (calcined lime dolomite) and FeSiAl with size 0.1-5 mm. The reducing process is running for 8 hours in a retort at 1,200° C. and
vacuum 10−2 atm. - A. Doloma—1.7 ton, size 0.1 to 2.0 mm
-
CaO 50.3% MgO 35.5% SiO2 1.8% FeO 1.0% Al2O3 0.8% P2O5 0.03% Ignition losses 10.57%. - B. FeSiAl—0.25 ton, size 0.1-5 mm
-
Si 77.8% Al 7.2% Ca 0.70% Ti 0.50% C 0.12% P 0.009% S 0.002% Fe balance - At the end of the smelting process is obtained a pure magnesium metal (99.9%) and slag.
-
- 1 carbonaceous rock
- 2 bin (hopper)
- 3 vibration feeder
- 4 conveyor
- 5 crusher
- 6 screen
- 7 quartzite
- 8 bin (hopper)
- 9 vibration feeder
- 10 conveyor belt
- 11 crusher unit
- 12 screen
- 13 hopper
- 14 hopper
- 15 hopper
- 15 a iron turnings
- 16 dosing strain-gage weighter
- 17 dosing strain-gage weighter
- 18 dosing strain-gage weighter
- 19 belt conveyor
- 20 transport equipment
- 21 Søderberg electrodes
- 22 cone
- 23 melting furnace
- B hopper
- H wood chips
Claims (20)
1. A method of producing FeSiAl alloys wherein a carbonaceous rock with an ash content >50% to <65%, is being mixed with quartzite, iron-bearing material, and wood chips, if required, high volatile coal, in a preset ratio of the charge components and the homogenized charge material is being loaded into a melting furnace for melting of FeSiAl alloy, the charged carbonaceous rock can contain i.a. the following chemical composition in the mineral part (ash):
2. The method under claim 1 , wherein the charge materials are mixed and homogenized outside the melting furnace, and then the homogenized charge is loaded dosed into the melting furnace equipped with electrodes cone up, and then the FeSiAl alloy is being smelted.
3. The method under claim 1 , wherein the carbonaceous rock has a size >20 to 80 mm, the quartzite has a size 25 to 60 mm and the iron-bearing material has a size 5 to 100 mm, in particular 5 to 50 mm.
4. The method under claim 1 , wherein the wood chips or the high volatile coal has a size 50-100 mm.
5. The method under claim 1 , wherein while using the wood chips the raw material has >50% of volatile matter.
6. The method according to claim 1 , wherein while using high volatile coal the raw material has >40% volatile matter.
7. The method under claim 1 , wherein the charge materials carbonaceous rock, quartzite and iron-containing material, if required wood chips or high volatile coal are stored in separate bins (hoppers) with the required fraction size and, depending on the capacity of the melting furnace, are mixed in a preset ratio and are loaded dosed into the melting furnace equipped with Søderberg electrodes.
8. The method under claim 1 , wherein carbonaceous rock with high electrical resistance is used as a raw material, in particular with an electrical resistance between 10−6Ω and 10−1Ω.
9. The method under claim 1 , wherein, if required, the following oxide materials containing Mn, Ca, Ba, Cr, V, Ti are being individually added to the charge materials.
10. The method under claim 9 , wherein the quantity of the oxide material added, if required, to the composition of the charge, secures the following composition of the charge:
11. The method under claim 1 , wherein FeSiAl alloys with the following chemical composition is being melted in the melting furnace (mass-%):
12. The method under claim 10 , wherein manganese in form of oxide material is added, if required, to the charge material whereby a FeSiAl alloy with the following chemical composition is melted in the melting furnace:
and in the same manner, if required, are added Ca, Ba, V, Ti and Cr in form of oxide materials to secure the content of these elements, each of them individually, as per claim 10 .
13. The FeSiAl alloy produced under the method of claim 1 is used for reducing and doping of steel.
14. The FeSiAl alloy produced under the method of claim 1 is used for production of magnesium.
15. The FeSiAl alloy produced under the method of claim 1 is used for production of refined grades of ferroalloys.
16. The method under claim 2 , wherein the carbonaceous rock has a size >20 to 80 mm, the quartzite has a size 25 to 60 mm and the iron-bearing material has a size 5 to 100 mm, in particular 5 to 50 mm.
17. The method under claim 2 , wherein the wood chips or the high volatile coal has a size 50-100 mm.
18. The method under claim 3 , wherein the wood chips or the high volatile coal has a size 50-100 mm.
19. The method under claim 2 , wherein while using the wood chips the raw material has >50% of volatile matter.
20. The method under claim 3 , wherein while using the wood chips the raw material has >50% of volatile matter.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP15000931.4A EP3075869B1 (en) | 2015-03-30 | 2015-03-30 | Method for production of iron-silicon-aluminum alloys |
EP15000931.4 | 2015-03-30 | ||
PCT/EP2016/000506 WO2016155873A1 (en) | 2015-03-30 | 2016-03-23 | Method for production of iron-silicon-aluminum alloys and their use |
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US20180371562A1 true US20180371562A1 (en) | 2018-12-27 |
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US15/563,038 Abandoned US20180371562A1 (en) | 2015-03-30 | 2016-03-23 | Method for production of iron-silicon-aluminum alloys and their use |
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Country | Link |
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US (1) | US20180371562A1 (en) |
EP (1) | EP3075869B1 (en) |
JP (1) | JP2018513921A (en) |
KR (1) | KR20170126000A (en) |
CN (1) | CN107429306A (en) |
AU (1) | AU2016239262A1 (en) |
BR (1) | BR112017020659A2 (en) |
CA (1) | CA2980499A1 (en) |
EA (1) | EA037656B1 (en) |
PL (1) | PL3075869T3 (en) |
WO (1) | WO2016155873A1 (en) |
ZA (1) | ZA201706390B (en) |
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CN115747415A (en) * | 2022-11-16 | 2023-03-07 | 中冶东方工程技术有限公司 | Electric furnace feeding system suitable for transforming long flow of converter into short flow of electric furnace |
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NO343946B1 (en) * | 2018-04-03 | 2019-07-22 | Elkem Materials | Silicon based alloy, method for the production thereof and use of such alloy |
NO20180804A1 (en) * | 2018-06-11 | 2019-12-12 | Elkem Materials | Silicon based alloy, method for the production thereof and use of such alloy |
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-
2016
- 2016-03-23 KR KR1020177030933A patent/KR20170126000A/en unknown
- 2016-03-23 CA CA2980499A patent/CA2980499A1/en not_active Abandoned
- 2016-03-23 BR BR112017020659A patent/BR112017020659A2/en not_active Application Discontinuation
- 2016-03-23 WO PCT/EP2016/000506 patent/WO2016155873A1/en active Application Filing
- 2016-03-23 EA EA201792150A patent/EA037656B1/en unknown
- 2016-03-23 US US15/563,038 patent/US20180371562A1/en not_active Abandoned
- 2016-03-23 JP JP2018502318A patent/JP2018513921A/en active Pending
- 2016-03-23 CN CN201680019568.5A patent/CN107429306A/en active Pending
- 2016-03-23 AU AU2016239262A patent/AU2016239262A1/en not_active Abandoned
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Publication number | Publication date |
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EA037656B1 (en) | 2021-04-27 |
EP3075869A1 (en) | 2016-10-05 |
PL3075869T3 (en) | 2019-04-30 |
EP3075869B1 (en) | 2018-10-17 |
ZA201706390B (en) | 2019-05-29 |
JP2018513921A (en) | 2018-05-31 |
KR20170126000A (en) | 2017-11-15 |
BR112017020659A2 (en) | 2018-07-03 |
EA201792150A1 (en) | 2018-01-31 |
CN107429306A (en) | 2017-12-01 |
AU2016239262A1 (en) | 2017-10-12 |
CA2980499A1 (en) | 2016-10-06 |
WO2016155873A1 (en) | 2016-10-06 |
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