CN110616378A - Production method of high-purity silicon iron for producing silicon steel - Google Patents
Production method of high-purity silicon iron for producing silicon steel Download PDFInfo
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- CN110616378A CN110616378A CN201910896961.8A CN201910896961A CN110616378A CN 110616378 A CN110616378 A CN 110616378A CN 201910896961 A CN201910896961 A CN 201910896961A CN 110616378 A CN110616378 A CN 110616378A
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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
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
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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
- C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
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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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Silicon Compounds (AREA)
Abstract
The invention relates to a production method of high-purity silicon iron for producing silicon steel, which is characterized in that silicon mud and an adhesive are mixed, stirred, granulated and dried, then are melted at high temperature in a medium-frequency induction furnace, and then are cast in a silicon iron tank, cooled and crushed to obtain a high-purity silicon iron product. The invention utilizes silicon mud produced by photovoltaic industry, selects proper raw materials and process conditions, and produces high-purity silicon iron for smelting silicon steel. After the method is implemented, the environmental pollution caused by the silicon mud is reduced; the power consumption of the silicon iron produced by the method is 2800-.
Description
Technical Field
The invention relates to the technical field of alloy production, in particular to a production method of high-purity silicon iron for producing silicon steel.
Background
Currently, ferrosilicon smelting at home and abroad adopts silica, metallurgical coke (petroleum coke, charcoal, coal and the like), steel scraps (or iron ore) to be reduced in an ore-smelting furnace, and a multi-element slag absorption method is used outside the furnace to remove partial impurities, so that the process is complex and the energy consumption is high. The traditional compounding method is that the ratio of silica, coke and steel scrap is 100: (48-56): 26 silica with SiO2 > 97% can be used, the coke particle size is 5-18 mm. Its disadvantages are high metallurgical coke ash content, large coke granularity, small surface area and long reduction reaction time.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a production method of high-purity silicon iron for producing silicon steel.
In order to achieve the purpose, the invention adopts the following technical scheme: a production method of high-purity silicon iron for producing silicon steel is characterized by comprising the following production steps:
a granulation drying
Mixing and stirring the silicon mud and the adhesive, pressing balls after mixing to produce silicon mud particles, and then drying the silicon mud particles;
b high temperature melting
Mixing the granulated and dried silicon mud particles with reduced iron powder, wherein the particle size of the silicon mud particles is 0-50mm, electrifying a medium-frequency induction furnace, heating and baking to more than 1000 ℃, introducing inert gas for protection into the medium-frequency induction furnace, gradually adding the mixed silicon mud particles and the reduced iron powder into a hearth, simultaneously, filling the hearth until the hearth is full, maintaining the charge level, adding the silicon mud particles and the reduced iron powder in sequence, tamping and pricking holes according to needs, properly adding a slag former according to conditions, continuously smelting, intermittently starting the furnace, sampling and analyzing, discharging after the silicon mud particles and the reduced iron powder are qualified, wherein the first discharging time is longer, and the periodic furnace discharging time is different according to the volume;
c cooling and crushing
Discharging the smelting product obtained after the high-temperature melting in the step B into a ferrosilicon tank for ingot casting, and then cooling and crushing the ingot casting to obtain a high-purity ferrosilicon product;
d warehouse entry
And inspecting and packaging the high-purity ferrosilicon, and warehousing after packaging is finished.
The chemical component mass percentage requirement of the silicon mud in the step A is SiO2＞90.0％，Al2O3Less than 0.03 percent, less than 0.01 percent of CaO and less than 0.02 percent of the total of other impurities except ferric oxide.
And the granularity of the silicon mud particles in the step B is 5-40 mm.
In the step B, the weight ratio of the silicon mud particles to the reduced iron powder is 100: 25.
And B, producing on a 1600KVA intermediate frequency induction furnace, wherein the main parameters are as follows: the furnace type is a steel shell medium frequency induction furnace, the inlet wire voltage of the induction furnace is 550V, the outer diameter of the furnace shell is 1400mm, the height of the furnace shell is 1600mm, the inner diameter of the hearth is 1000mm, the depth of the hearth is 1400mm, the diameter of the electrode is 500mm, the electrode is a high-power or ultrahigh-power electrode, and the lining is siliceous.
In the step B, external refining is not needed under normal conditions, and due to the addition of the slag former, when the impurities of the discharged product exceed the standard, a small amount of chlorine, oxygen or chlorine-oxygen can be introduced according to the impurity components to carry out external liquid refining.
C, controlling the impurity content mass percent of the high-purity silicon iron product obtained in the step C to be in the following range; 0.05 to 0.003 percent of C, 0.01 to 0.002 percent of S, less than 0.02 percent of P, 0.05 to 0.001 percent of V, 0.01 to 0.002 percent of B, less than 0.10 percent of Mn, 0.05 to 0.005 percent of Mg0.05 to 0.007 percent of Tis, 0.05 to 0.002 percent of Ca0.05 percent of Ca, less than 0.05 percent of Cr, less than 0.05 percent of Ni, 0.01 to 0.003 percent of Zrs, less than 0.1 percent of Al, and less than 0.05 percent of the total amount of other impurities.
The invention has the beneficial effects that: the invention utilizes silicon mud produced by photovoltaic industry, selects proper raw materials and process conditions, and produces high-purity silicon iron for smelting silicon steel. After the method is implemented, the environmental pollution caused by the silicon mud is reduced; the power consumption of the silicon iron produced by the method is 2800-.
Drawings
FIG. 1 is a process flow diagram of the present invention;
the following detailed description will be made in conjunction with embodiments of the present invention with reference to the accompanying drawings.
Detailed Description
The invention is further illustrated by the following examples in conjunction with the accompanying drawings:
as shown in FIG. 1, a method for producing high-purity silicon iron for silicon steel, which is characterized by comprising the following steps:
a granulation drying
Mixing and stirring the silicon mud and the adhesive, pressing balls after mixing to produce silicon mud particles, and then drying the silicon mud particles;
b high temperature melting
Mixing the granulated and dried silicon mud particles with reduced iron powder, wherein the particle size of the silicon mud particles is 0-50mm, electrifying a medium-frequency induction furnace, heating and baking to more than 1000 ℃, introducing inert gas for protection into the medium-frequency induction furnace, gradually adding the mixed silicon mud particles and the reduced iron powder into a hearth, simultaneously, filling the hearth until the hearth is full, maintaining the charge level, adding the silicon mud particles and the reduced iron powder in sequence, tamping and pricking holes according to needs, properly adding a slag former according to conditions, continuously smelting, intermittently starting the furnace, sampling and analyzing, discharging after the silicon mud particles and the reduced iron powder are qualified, wherein the first discharging time is longer, and the periodic furnace discharging time is different according to the volume;
c cooling and crushing
Discharging the smelting product obtained after the high-temperature melting in the step B into a ferrosilicon tank for ingot casting, and then cooling and crushing the ingot casting to obtain a high-purity ferrosilicon product;
d warehouse entry
And inspecting and packaging the high-purity ferrosilicon, and warehousing after packaging is finished.
The chemical component mass percentage requirement of the silicon mud in the step A is SiO2＞90.0％，Al2O3Less than 0.03 percent, less than 0.01 percent of CaO and less than 0.02 percent of the total of other impurities except ferric oxide.
And the granularity of the silicon mud particles in the step B is 5-40 mm.
In the step B, the weight ratio of the silicon mud particles to the reduced iron powder is 100: 25.
And B, producing on a 1600KVA intermediate frequency induction furnace, wherein the main parameters are as follows: the furnace type is a steel shell medium frequency induction furnace, the inlet wire voltage of the induction furnace is 550V, the outer diameter of the furnace shell is 1400mm, the height of the furnace shell is 1600mm, the inner diameter of the hearth is 1000mm, the depth of the hearth is 1400mm, the diameter of the electrode is 500mm, the electrode is a high-power or ultrahigh-power electrode, and the lining is siliceous.
In the step B, external refining is not needed under normal conditions, and due to the addition of the slag former, when the impurities of the discharged product exceed the standard, a small amount of chlorine, oxygen or chlorine-oxygen can be introduced according to the impurity components to carry out external liquid refining.
C, controlling the impurity content mass percent of the high-purity silicon iron product obtained in the step C to be in the following range; 0.05 to 0.003 percent of C, 0.01 to 0.002 percent of S, less than 0.02 percent of P, 0.05 to 0.001 percent of V, 0.01 to 0.002 percent of B, less than 0.10 percent of Mn, 0.05 to 0.005 percent of Mg0.05 to 0.007 percent of Tis, 0.05 to 0.002 percent of Ca0.05 percent of Ca, less than 0.05 percent of Cr, less than 0.05 percent of Ni, 0.01 to 0.003 percent of Zrs, less than 0.1 percent of Al, and less than 0.05 percent of the total amount of other impurities.
Example 1
A production method of high-purity silicon iron for producing silicon steel is characterized by comprising the following production steps:
a granulation drying
Mixing and stirring silicon mud and an adhesive, pressing balls after mixing to produce silicon mud particles, and then drying the silicon mud particles, wherein the chemical component mass percentage of the silicon mud is required to be SiO2＞90.0％，Al2O3＜0.03％，CaO＜0.01％，The sum of other impurities except ferric oxide is less than 0.02 percent;
b high temperature melting
Mixing the granulated and dried silicon sludge particles with reduced iron powder according to the weight ratio of 100:25, electrifying a medium-frequency induction furnace, heating and baking to more than 1000 ℃, introducing inert gas for protection into the medium-frequency induction furnace, gradually adding the mixed silicon sludge particles and the reduced iron powder into the hearth, and simultaneously filling the hearth, then maintaining the charge level, adding along with the shortage, stoking and piercing according to the needs, adding slag former according to the situation, continuously smelting, intermittently blowing in the furnace, sampling and analyzing, discharging after being qualified, the first discharging time is longer, then the regular discharging time is different according to the volume, the external refining is not needed under the normal condition, because the addition of the slag former brings that the impurities of the discharged product exceed the standard, a small amount of chlorine gas, oxygen or chlorine-oxygen can be introduced according to impurity components for liquid refining outside the furnace;
c cooling and crushing
Discharging the smelting product obtained after the high-temperature melting in the step B into a ferrosilicon tank for ingot casting, and then cooling and crushing the ingot casting to obtain a high-purity ferrosilicon product;
d warehouse entry
And inspecting and packaging the high-purity ferrosilicon, and warehousing after packaging is finished.
The test production is carried out on a 1600KVA intermediate frequency furnace, and the main parameters are as follows: the furnace type is a steel shell medium frequency induction furnace, the inlet wire voltage of the induction furnace is 550V, the outer diameter of the furnace shell is 1400mm, the height of the furnace shell is 1600mm, the inner diameter of the hearth is 1000mm, the depth of the hearth is 1400mm, the diameter of the electrode is 500mm, the electrode is a high-power or ultrahigh-power electrode, and the lining is siliceous. The raw materials are silicon mud particles of 0-50mm and low-carbon reduced iron powder of 0-5 mm. Under the normal condition of electric power, the power consumption is 2800-.
The invention utilizes silicon mud produced by photovoltaic industry, selects proper raw materials and process conditions, and produces high-purity silicon iron for smelting silicon steel. After the method is implemented, the environmental pollution caused by the silicon mud is reduced; the invention reduces the power consumption of the high-purity silicon iron by more than half.
The invention is described above with reference to the accompanying drawings, it is obvious that the invention is not limited to the above-described embodiments, and it is within the scope of the invention to use various modifications of the inventive concept and solution, or to apply the same to other applications without modification.
Claims (7)
1. A production method of high-purity silicon iron for producing silicon steel is characterized by comprising the following production steps:
a granulation drying
Mixing and stirring the silicon mud and the adhesive, pressing balls after mixing to produce silicon mud particles, and then drying the silicon mud particles;
b high temperature melting
Mixing the granulated and dried silicon mud particles with reduced iron powder, wherein the particle size of the silicon mud particles is 0-50mm, electrifying a medium-frequency induction furnace, heating and baking the silicon mud particles to more than 1000 ℃, introducing inert gas for protection into the medium-frequency induction furnace, gradually adding the mixed silicon mud particles and the reduced iron powder into a hearth, simultaneously filling the hearth until the hearth is full, maintaining the charge level, adding the silicon mud particles and the reduced iron powder along with the charge level, tamping and piercing the hearth according to the needs, properly adding a slag former according to the situation, continuously smelting, intermittently opening the hearth, sampling and analyzing, discharging after the hearth is qualified, wherein the first discharging time is longer, and then the regular discharging time is different according to the volume;
c cooling and crushing
Discharging the smelting product obtained after the high-temperature melting in the step B into a ferrosilicon tank for ingot casting, and then cooling and crushing the ingot casting to obtain a high-purity ferrosilicon product;
d warehouse entry
And inspecting and packaging the high-purity ferrosilicon, and warehousing after packaging is finished.
2. The method for producing high-purity Si-Fe for silicon steel according to claim 1, wherein the chemical composition of Si slurry in the step A is SiO in mass percent2＞90.0％，Al2O3Less than 0.03 percent, less than 0.01 percent of CaO and less than 0.02 percent of the total of other impurities except ferric oxide.
3. The method for producing high-purity ferrosilicon for silicon steel according to claim 1, wherein the grain size of the silicon sludge in step B is 5 to 40 mm.
4. The method for producing high-purity ferrosilicon for silicon steel according to claim 1, wherein the weight ratio of the silicon sludge particles to the reduced iron powder in step B is 100: 25.
5. The method for producing high-purity ferrosilicon for silicon steel according to claim 1, wherein the production in step B is carried out in a 1600KVA medium frequency induction furnace, and the main parameters are as follows: the furnace type is a steel shell medium frequency induction furnace, the inlet wire voltage of the induction furnace is 550V, the outer diameter of the furnace shell is 1400mm, the height of the furnace shell is 1600mm, the inner diameter of the hearth is 1000mm, the depth of the hearth is 1400mm, the diameter of the electrode is 500mm, the electrode is a high-power or ultrahigh-power electrode, and the lining is siliceous.
6. The method of claim 1, wherein in step B, the external refining is not required, and the impurities of the discharged product are more than standard due to the addition of the slag former, and the external liquid refining is performed by introducing a small amount of chlorine, oxygen, or chlorine-oxygen into the impurities.
7. The method for producing high-purity Si-Fe for silicon steel according to claim 1, wherein the impurity content of the high-purity Si-Fe product obtained in step C is controlled in the following range; 0.05 to 0.003 percent of C, 0.01 to 0.002 percent of S, less than 0.02 percent of P, 0.05 to 0.001 percent of V, 0.01 to 0.002 percent of B, less than 0.10 percent of Mn, 0.05 to 0.005 percent of Mg0.05 to 0.007 percent of Tis, 0.05 to 0.002 percent of Ca0.05 percent of Ca, less than 0.05 percent of Cr, less than 0.05 percent of Ni, 0.01 to 0.003 percent of Zrs, less than 0.1 percent of Al and less than 0.05 percent of the total amount of other impurities.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910896961.8A CN110616378A (en) | 2019-09-23 | 2019-09-23 | Production method of high-purity silicon iron for producing silicon steel |
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| CN201910896961.8A CN110616378A (en) | 2019-09-23 | 2019-09-23 | Production method of high-purity silicon iron for producing silicon steel |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1048067A (en) * | 1990-07-07 | 1990-12-26 | 湖北省十堰市铁合金厂 | Barium-silicon-iron alloy production process |
| CN1281819A (en) * | 2000-08-31 | 2001-01-31 | 齐国庆 | New method for smelting industrial silium and ferro-silicon and its equipment |
| CN103695768A (en) * | 2013-12-25 | 2014-04-02 | 嵩县开拓者钼业有限公司 | Tungsten-molybdenum-iron alloy and preparation method for same |
| CN107385264A (en) * | 2017-07-19 | 2017-11-24 | 常州赛蓝光伏技术有限公司 | Utilize the method for the clay standby silicon alloy of useless silicon |
-
2019
- 2019-09-23 CN CN201910896961.8A patent/CN110616378A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1048067A (en) * | 1990-07-07 | 1990-12-26 | 湖北省十堰市铁合金厂 | Barium-silicon-iron alloy production process |
| CN1281819A (en) * | 2000-08-31 | 2001-01-31 | 齐国庆 | New method for smelting industrial silium and ferro-silicon and its equipment |
| CN103695768A (en) * | 2013-12-25 | 2014-04-02 | 嵩县开拓者钼业有限公司 | Tungsten-molybdenum-iron alloy and preparation method for same |
| CN107385264A (en) * | 2017-07-19 | 2017-11-24 | 常州赛蓝光伏技术有限公司 | Utilize the method for the clay standby silicon alloy of useless silicon |
Non-Patent Citations (1)
| Title |
|---|
| 戴永年等: ""造渣氧化精炼提纯冶金级硅研究进展"", 《真空科学与科技学报》 * |
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