CN115449594A - Stainless steel smelting method using high chromium to replace low chromium - Google Patents
Stainless steel smelting method using high chromium to replace low chromium Download PDFInfo
- Publication number
- CN115449594A CN115449594A CN202210995654.7A CN202210995654A CN115449594A CN 115449594 A CN115449594 A CN 115449594A CN 202210995654 A CN202210995654 A CN 202210995654A CN 115449594 A CN115449594 A CN 115449594A
- Authority
- CN
- China
- Prior art keywords
- chromium
- stainless steel
- furnace
- added
- smelting method
- 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.)
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- 239000011651 chromium Substances 0.000 title claims abstract description 90
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 title claims abstract description 82
- 229910052804 chromium Inorganic materials 0.000 title claims abstract description 82
- 238000003723 Smelting Methods 0.000 title claims abstract description 39
- 238000000034 method Methods 0.000 title claims abstract description 34
- 239000010935 stainless steel Substances 0.000 title claims abstract description 28
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 28
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 37
- 239000010959 steel Substances 0.000 claims abstract description 37
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 23
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 23
- 239000001301 oxygen Substances 0.000 claims abstract description 23
- 238000007664 blowing Methods 0.000 claims abstract description 13
- 238000002844 melting Methods 0.000 claims abstract description 12
- 230000008018 melting Effects 0.000 claims abstract description 12
- 229910000519 Ferrosilicon Inorganic materials 0.000 claims abstract description 7
- 239000002893 slag Substances 0.000 claims abstract description 7
- 238000007670 refining Methods 0.000 claims abstract description 5
- 238000010079 rubber tapping Methods 0.000 claims abstract description 5
- 238000009792 diffusion process Methods 0.000 claims abstract description 4
- 238000012840 feeding operation Methods 0.000 claims abstract description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 239000000843 powder Substances 0.000 claims description 2
- 230000009467 reduction Effects 0.000 abstract description 2
- 230000008569 process Effects 0.000 description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000005261 decarburization Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000036284 oxygen consumption Effects 0.000 description 2
- 229910000599 Cr alloy Inorganic materials 0.000 description 1
- 229910000604 Ferrochrome Inorganic materials 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000011449 brick Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000000788 chromium alloy Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0006—Adding metallic additives
-
- 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
- C21C7/06—Deoxidising, e.g. killing
-
- 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
- C21C7/068—Decarburising
-
- 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
Abstract
The invention belongs to the technical field of steel smelting, and provides a stainless steel smelting method for replacing low chromium with high chromium. The stainless steel smelting method comprises the following steps: (1) electric furnace high chromium replacing low chromium: after a molten pool is formed in the melting period of the electric furnace, high chromium is firstly added, and then scrap steel is added until the Cr in the furnace reaches the specification lower limit +0.30 percent and the C reaches 0.50-0.80 percent; melting down furnace charge, adding 0.3% ferrosilicon, blowing oxygen at 1560-1570 deg.C under oxygen pressure of 1.3-1.5Mpa and oxygen flow of 200-250NM 3 H; and (2) reduction tapping: after the oxygen blowing is finished, adding a strong deoxidizer into the furnace for diffusion deoxidation, so that the slag has good fluidity and is brown; (3) low chromium trim: after VOD refining, the temperature of molten steel is 1690-1700 ℃, low chromium is added to be cooled to 1600 ℃, and wire feeding operation is carried out. By adopting the smelting method, the smelting time is shortened, and the electric energy is reducedAnd the consumption of furnace lining, ladle lining and the like, and the high chromium is greatly used for replacing the low chromium, so that the smelting cost is directly reduced, and the method has good practicability.
Description
Technical Field
The invention belongs to the technical field of steel smelting, and particularly relates to a stainless steel smelting method for replacing low chromium with high chromium.
Background
In the production process of the stainless steel 'electric furnace + LF + VOD' process route, american standard (P is less than or equal to 0.045%) scrap steel is often used for producing national standard (P is less than or equal to 0.035%) stainless steel, so that low-P pure iron, nickel plates and ferrochrome are required to be added to reduce the P content in the furnace in a 'concentration difference' mode.
And the smelting cost of the stainless steel is high for a long time due to the fact that the low chromium is mainly used (about 100 kg/ton of molten steel) and the high chromium is used as the auxiliary (about 20 kg/ton of molten steel) under the condition that the C + Si is less than or equal to 0.70 percent by VOD (vacuum oxygen decarburization) in the tank.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a stainless steel smelting method for replacing low chromium with high chromium, and by adopting the smelting method, the smelting time is shortened, the consumption of electric energy, furnace lining, ladle lining and the like is reduced, the high chromium is greatly used for replacing the low chromium, the smelting cost is directly reduced, and the smelting method has good practicability.
In order to achieve the above purpose, the solution adopted by the invention is as follows:
a method for smelting stainless steel with high chromium instead of low chromium comprises the following steps: (1) electric furnace high chromium instead of low chromium: after a molten pool is formed in the melting period of the electric furnace, high chromium is firstly added, and then scrap steel is added until the Cr in the furnace reaches the specification lower limit +0.30 percent and the C reaches 0.50-0.80 percent; melting down furnace charge, adding 0.3% ferrosilicon, blowing oxygen at 1560-1570 deg.C under oxygen pressure of 1.3-1.5Mpa and oxygen flow of 200-250NM 3 H; and (2) reducing and tapping: after the oxygen blowing is finished, adding a strong deoxidizer for diffusion deoxidation to ensure that the slag has good fluidity and is brown; (3) low chromium trim: after VOD refining, the temperature of molten steel is 1690-1700 ℃, low chromium is added until the temperature is reduced to 1600 ℃, and wire feeding operation is carried out.
Further, in a preferred embodiment of the present invention, in the step (1), high chromium is added in an amount of 80 to 100kg/t of molten steel.
Further, in a preferred embodiment of the present invention, in the step (1), high chromium is added in an amount of 90kg/t molten steel.
Further, in the preferred embodiment of the present invention, in step (1), when the temperature is 1560-1570 ℃, the deep oxygen blowing is started.
Further, in a preferred embodiment of the present invention, in the step (2), the deoxidizer includes aluminum powder, carbon powder or ferrosilicon powder.
Further, in the preferred embodiment of the present invention, in the step (3), low chromium is added in an amount of 35kg/t of molten steel.
The stainless steel smelting method using high chromium to replace low chromium provided by the invention has the beneficial effects that:
(1) In the application, after a molten pool is formed in the melting period of the electric furnace, high chromium is added firstly, and then scrap steel is added, so that electric arcs can be prevented from being directly projected onto the high chromium, and the burning loss of the high chromium is reduced; according to the principle of chromium oxidation kinetics, increasing the C content in steel can reduce [ Cr]/[C]Balancing constant, and reducing oxygen blowing temperature of decarburization and chromium retention; controlling Cr in the furnace to reach the lower limit of specification +0.30%, C to reach 0.50-0.80%, and reducing the melting point of molten steel after the content of C in the molten steel is increased, thereby not only accelerating the melting speed of scrap steel, shortening the melting period by more than 20 minutes, and correspondingly reducing the power consumption and the furnace lining consumption, but also being matched with chromium alloy required by pure iron; adding 0.3% ferrosilicon after furnace charge is melted down, blowing oxygen at 1560-1570 ℃, releasing a large amount of heat from the earlier stage of silicon oxide, and when the oxygen pressure is 1.3-1.5Mpa and the flow is 200-250NM 3 And/h, only carbon is basically oxidized and chromium is not oxidized, so that the aim of decarbonizing and retaining chromium is fulfilled.
(2) In the application, high chromium is greatly used to replace low chromium, so that the smelting cost can be directly reduced.
(3) In the application, after oxygen blowing is finished, a large amount of viscous chromium slag is generated in the furnace, which influences tapping and chromium yield, therefore, strong deoxidizer is added in the furnace until the slag has good fluidity and brown color, and the slag has good reducibility and does not influence the chromium yield.
(4) In the application, a small amount of low chromium is reserved for use after VOD refining, so that the chemical components in the steel are finely adjusted, the cold material is used as the cold material to reduce the temperature of the molten steel, a large amount of time for waiting for cooling is saved, the consumption of the lining is reduced, and the purposes of reducing the smelting cost and improving the quality of the molten steel are achieved.
By adopting the stainless steel smelting method using high chromium to replace low chromium, the smelting time is shortened, the consumption of electric energy, furnace lining, packing and the like is reduced, the high chromium is used to replace the low chromium to a great extent, the smelting cost is directly reduced, and the method has good practicability.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are conventional products which are not indicated by manufacturers and are commercially available.
The features and properties of the present invention are described in further detail below with reference to examples.
Example 1
The embodiment provides a stainless steel smelting method for replacing low chromium with high chromium, which comprises the following steps: (1) electric furnace high chromium replacing low chromium: after a molten pool is formed in the melting period of the electric furnace, high chromium is added according to 90kg/t molten steel, then scrap steel is added until Cr in the furnace reaches the specification lower limit +0.30% (the specification lower limit refers to the specification lower limit of Cr contained in stainless steel, the stainless steel refers to all the stainless steel containing Cr), and C reaches 0.50-0.80%; melting down the furnace charge, adding 0.3% ferrosilicon, blowing oxygen at 1560-1570 deg.C under 1.3-1.5Mpa with oxygen flow rate of 200-250NM 3 H; and (2) reduction tapping: after the oxygen blowing is finished, adding a strong deoxidizer for diffusion deoxidation, so that the slag has good fluidity and is brown; (3) low chromium trim: after VOD refining, the temperature of molten steel is 1690-1700 ℃, low chromium is added to be cooled to 1600 ℃, and wire feeding operation is carried out (the rest parts which are not recorded can refer to the stainless steel 'electric furnace + LF + VOD' process route in the prior art).
Experimental example 1
In the stainless steel "electric furnace + LF + VOD" route, the stainless steel smelting process (new process) using the high chromium instead of the low chromium provided in example 1 is compared with the old process as follows: of run-flat brick No. 13
TABLE 1 comparison of high and low chromium levels for the new and old processes
TABLE 2 comparison of oxygen, electricity consumption and lining consumption in new and old process
| Item | Old process | New process | Increase or decrease |
| Oxygen consumption | 6kg/t molten steel | 28kg/t molten steel | +22kg/t molten steel |
| Consumption of electric energy | 850kwh/t molten steel | 740kwh/t molten steel | -110kwh/t molten steel |
| Lining wear | 15kg/t molten steel | 13kg/t molten steel | -2kg/t molten steel |
According to the results in tables 1 and 2, compared with the prior art, the stainless steel smelting method using high chromium to replace low chromium provided by the application has the advantages that although the electric furnace increases the oxygen consumption, the smelting time is saved by at least 20 minutes, the electric energy and the furnace lining consumption are reduced, and the saved cost is far more than the increased cost of oxygen (table 2); the electric furnace greatly uses high chromium to replace low chromium, and because the price of the high chromium is far lower than that of the low chromium, the smelting cost can be directly reduced (table 1). Therefore, compared with the prior art, the stainless steel smelting method using high chromium to replace low chromium provided by the application can reduce energy consumption, shorten smelting time, remarkably reduce production cost, has good practicability, and is suitable for large-scale industrialization.
In conclusion, the stainless steel smelting method using high chromium to replace low chromium provided by the invention not only shortens the smelting time and reduces the consumption of electric energy, furnace lining, ladle lining and the like, but also greatly uses high chromium to replace low chromium, directly reduces the smelting cost and has good practicability.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. A stainless steel smelting method using high chromium to replace low chromium is characterized in that: the method comprises the following steps:
(1) Electric furnace high chromium instead of low chromium: after a molten pool is formed in the melting period of the electric furnace, high chromium is firstly added, and then scrap steel is added until the Cr in the furnace reaches the specification lower limit +0.30 percent and the C reaches 0.50-0.80 percent; melting down the furnace charge, adding 0.3% ferrosilicon, blowing oxygen at 1560-1570 deg.C under 1.3-1.5Mpa with oxygen flow rate of 200-250NM 3 /h；
(2) Reducing and tapping: after the oxygen blowing is finished, adding a strong deoxidizer for diffusion deoxidation to ensure that the slag has good fluidity and is brown;
(3) Low chromium trim: after VOD refining, the temperature of molten steel is 1690-1700 ℃, low chromium is added to be cooled to 1600 ℃, and wire feeding operation is carried out.
2. The stainless steel smelting method according to claim 1, wherein: in the step (1), the high chromium is added according to 80-100kg/t molten steel.
3. The stainless steel smelting method according to claim 2, wherein: in the step (1), the high chromium is added into the molten steel according to the proportion of 90 kg/t.
4. The stainless steel smelting method according to claim 1, wherein: in the step (1), when the temperature is 1560-1570 ℃, deep oxygen blowing is started.
5. The stainless steel smelting method according to claim 1, wherein: in the step (2), the deoxidizer comprises aluminum powder, carbon powder or ferrosilicon powder.
6. The stainless steel smelting method according to claim 2, wherein: in the step (3), the low chromium is added into the molten steel according to 35 kg/t.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210995654.7A CN115449594B (en) | 2022-08-18 | 2022-08-18 | Stainless steel smelting method using high chromium to replace low chromium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210995654.7A CN115449594B (en) | 2022-08-18 | 2022-08-18 | Stainless steel smelting method using high chromium to replace low chromium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115449594A true CN115449594A (en) | 2022-12-09 |
| CN115449594B CN115449594B (en) | 2023-11-28 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210995654.7A Active CN115449594B (en) | 2022-08-18 | 2022-08-18 | Stainless steel smelting method using high chromium to replace low chromium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115449594B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1812941A (en) * | 1926-12-18 | 1931-07-07 | Republic Steel Corp | Manufacture of stainless iron |
| GB400747A (en) * | 1932-08-19 | 1933-11-02 | Alexander Littlejohn Feild | Improvements in the manufacture of stainless iron |
| CN1066685A (en) * | 1992-05-15 | 1992-12-02 | 冶金工业部钢铁研究总院 | The method of arc furnace with top and bottom complex blowing smelting stainless steel |
| CN107058677A (en) * | 2017-05-22 | 2017-08-18 | 山西太钢不锈钢股份有限公司 | A kind of smelting process of utilization stainless steel electroslag |
| CN107217123A (en) * | 2017-05-26 | 2017-09-29 | 响水恒生不锈钢铸造有限公司 | A kind of AOD tappings processing method |
| CN108913983A (en) * | 2018-07-31 | 2018-11-30 | 河南中原特钢装备制造有限公司 | Corrosion resistance and the strong FV520B steel smelting method of impact flexibility |
-
2022
- 2022-08-18 CN CN202210995654.7A patent/CN115449594B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1812941A (en) * | 1926-12-18 | 1931-07-07 | Republic Steel Corp | Manufacture of stainless iron |
| GB400747A (en) * | 1932-08-19 | 1933-11-02 | Alexander Littlejohn Feild | Improvements in the manufacture of stainless iron |
| CN1066685A (en) * | 1992-05-15 | 1992-12-02 | 冶金工业部钢铁研究总院 | The method of arc furnace with top and bottom complex blowing smelting stainless steel |
| CN107058677A (en) * | 2017-05-22 | 2017-08-18 | 山西太钢不锈钢股份有限公司 | A kind of smelting process of utilization stainless steel electroslag |
| CN107217123A (en) * | 2017-05-26 | 2017-09-29 | 响水恒生不锈钢铸造有限公司 | A kind of AOD tappings processing method |
| CN108913983A (en) * | 2018-07-31 | 2018-11-30 | 河南中原特钢装备制造有限公司 | Corrosion resistance and the strong FV520B steel smelting method of impact flexibility |
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| CN115449594B (en) | 2023-11-28 |
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