CN102787201A - Application of coal as steelmaking slag pressing agent and method for inhibiting steel slag foaming - Google Patents
Application of coal as steelmaking slag pressing agent and method for inhibiting steel slag foaming Download PDFInfo
- Publication number
- CN102787201A CN102787201A CN2012103171898A CN201210317189A CN102787201A CN 102787201 A CN102787201 A CN 102787201A CN 2012103171898 A CN2012103171898 A CN 2012103171898A CN 201210317189 A CN201210317189 A CN 201210317189A CN 102787201 A CN102787201 A CN 102787201A
- Authority
- CN
- China
- Prior art keywords
- slag
- coal
- steel
- agent
- dephosphorization
- 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.)
- Pending
Links
- 239000002893 slag Substances 0.000 title claims abstract description 57
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 25
- 239000003245 coal Substances 0.000 title claims abstract description 18
- 238000009628 steelmaking Methods 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims description 12
- 229910000831 Steel Inorganic materials 0.000 title abstract description 29
- 239000010959 steel Substances 0.000 title abstract description 29
- 238000005187 foaming Methods 0.000 title 1
- 230000002401 inhibitory effect Effects 0.000 title 1
- 239000002817 coal dust Substances 0.000 claims description 14
- 238000007664 blowing Methods 0.000 claims description 10
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 8
- 229910052760 oxygen Inorganic materials 0.000 claims description 8
- 239000001301 oxygen Substances 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 3
- 239000003507 refrigerant Substances 0.000 claims description 3
- 230000005764 inhibitory process Effects 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 47
- 229910052742 iron Inorganic materials 0.000 abstract description 23
- 238000003723 Smelting Methods 0.000 abstract description 12
- 238000010079 rubber tapping Methods 0.000 abstract description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 239000000463 material Substances 0.000 abstract description 4
- 239000000126 substance Substances 0.000 abstract description 3
- 238000004134 energy conservation Methods 0.000 abstract 1
- 230000007613 environmental effect Effects 0.000 abstract 1
- 230000002035 prolonged effect Effects 0.000 abstract 1
- 238000005516 engineering process Methods 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 3
- 235000011941 Tilia x europaea Nutrition 0.000 description 3
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 3
- 238000005261 decarburization Methods 0.000 description 3
- 239000010436 fluorite Substances 0.000 description 3
- 239000004571 lime Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 241001062472 Stokellia anisodon Species 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000006477 desulfuration reaction Methods 0.000 description 2
- 230000023556 desulfurization Effects 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- 239000008188 pellet Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 241000143432 Daldinia concentrica Species 0.000 description 1
- 241000721047 Danaus plexippus Species 0.000 description 1
- RWDBMHZWXLUGIB-UHFFFAOYSA-N [C].[Mg] Chemical compound [C].[Mg] RWDBMHZWXLUGIB-UHFFFAOYSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 235000019504 cigarettes Nutrition 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- XWHPIFXRKKHEKR-UHFFFAOYSA-N iron silicon Chemical compound [Si].[Fe] XWHPIFXRKKHEKR-UHFFFAOYSA-N 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000036284 oxygen consumption Effects 0.000 description 1
- 230000033764 rhythmic process Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
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- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
The invention discloses the use of coal as a slag pressing agent for steelmaking, so that direct steel tapping can be realized without pouring slag before dephosphorization smelting, the smelting period is shortened, the average production period is shortened from original 35 minutes to 25 minutes, the consumption of steel and iron materials is effectively reduced, the service life of a converter lining is prolonged, the production targets of low cost, high efficiency, energy conservation and environmental protection for smelting semisteel by a dephosphorization furnace are realized, the environment is not influenced, and the requirements on chemical components and temperature of the semisteel are met.
Description
Technical field
The present invention relates to steelmaking technical field, particularly coal is pressed the purposes of slag agent and is suppressed the method that slag steeps as steel-making.
Background technology
Along with the rise of the steel market prices of raw and semifnished materials, while steel products user improves constantly quality product, can satisfy the requirement of smelting the high added value variety steel as a new generation's " complete three take off " technological process of production." complete three take off " molten iron refers to the molten iron after desulfurization, dephosphorization and the desiliconization.The base iron dephosphorization technology mainly carries out in metal mixer car, iron ladle etc.Since 20 beginnings of the century, Nippon Steel is factory in the Nagoya, the Sumitomo in Lu Daochang, Kawasaki Steel on the water island Iron And Steel Plant test special-purpose converter and carry out dephosphorization.To the end of the nineties; The converter dephosphorization technology reaches its maturity, and each major company popularizes in an all-round way and uses, and replaces metal mixer car and iron ladle dephosphorizing technology one after another; Especially monarch Tianjin Iron And Steel Plant of Japanese Nippon Steel all change the metal mixer car of two steelworkss into converter dephosphorization in the short period of time at the end of the nineties.The Sumitomo Wakayama factory that Japan went into operation in 1999 has built a converter dephosphorization workshop specially, specially to the decarburization converter dephosphorization molten iron is provided by the dephosphorization converter.
It is short that dephosphorization is bessemerized the time; Only 5～6 minutes; Converting process adds auxiliary materials such as lime, light-burned, ore and fluorite and carries out slag making, desiliconization and dephosphorization, and its dephosphorizing mainly relies on FeO content higher in the slag, and the contact area that strengthens between slag and the molten iron is carried out dephosphorization fast; Dephosphorization converter slag FeO is too high in the actual production process, and the reaction of slag steel is uneven.FeO control is higher in the slag brings many problems for the smelting of dephosphorization stove, and for example: iron loss is high, adds the ore not reduction basically of dephosphorization stove, and complete loss is in slag; Reduce slag desulfurization capacity; Contaminate environment, because the reaction of slag steel is uneven, FeO higher in the slag produces a large amount of red cigarettes with the reaction of half steel carbon in going out half steel or half steel transportation.Deslagging before dephosphorization is smelted always has a strong impact on the dephosphorization cycle; There is certain potential safety hazard etc. because splash takes place the slag bubble easily after the half steel finishing blowing.
The dephosphorization stove can be owing to FeO content higher (TFe reaches 16%) in the slag can't directly be tapped before the finishing blowing tapping steel; Need carry out preceding deslagging, and then tapping, smelting cycle and rhythm of production so both influenced; Improved iron and steel stock consumption simultaneously, steel-making cost increases.But adopting " complete three take off " smelting technology of converter dephosphorization technology at present is domestic first employing, though day present technique is ripe, because its confidentiality, the working specification that suppresses the slag bubble about dephosphorization stove finishing blowing does not also appear in the newspapers.
Conventional general employing carbon containing modification agent, the magnesium carbon balls etc. smelted of domestic steel mill are pressed the slag and the slag transformation of the way; Better for conventional metallurgical effect; But owing to reasons such as dephosphorization stove dephosphorization operation FeO content is higher, and the dephosphorisation reaction temperature is low cause the agent of ordinary pressure slag can't reach the purpose that suppresses the slag bubble.Usually need shake forward to about 78 ℃ deslagging in slag ladle after the converter dephosphorization finishing blowing, finish deslagging during 90 ℃ of deslagging to converter angles and tap.This working method not only influences 3-5 minute converter smelting cycle, also causes the significant wastage of iron and steel stock simultaneously.
Summary of the invention
Technical problem to be solved by this invention provides the purposes of a kind of coal as the agent of steel-making pressure slag, has solved the problem of deslagging before the dephosphorization converter tapping is necessary before.
For solving the problems of the technologies described above, the invention provides the purposes of coal as the agent of steel-making pressure slag, this pressure slag agent is base with the coal;
Further, said coal dust is a steam coal;
Further, the quality percentage composition of the full water of said coal dust is below 20%;
Further, the quality percentage composition of the combustible basis volatile matter of said coal dust is more than 20%, below 40%;
Further, the particle diameter of said coal dust is that 30mm is to 50mm;
When solving that dephosphorization is smelted in the steel-making always before deslagging; Have a strong impact on the problem in dephosphorization cycle; The present invention also provides the method that suppresses the slag bubble; Control converter temperature reduces 8-11 ℃; Every stove is added about 0.5 to 0.8 ton of cooling agent; Oxygen supply is opened and is blown 30000-35000Nm3/h in early stage, opens to blow after 2-3 minute to be adjusted into 20000-25000Nm3/h until finishing blowing; After the dephosphorization finishing blowing, in converter, add the agent of said pressure slag;
Further, said refrigerant is an agglomerate;
The present invention relates to coal as the purposes of steel-making pressure slag agent and the method for inhibition slag bubble thereof, through reducing finishing slag FeO content, dephosphorization is smelted need not just can directly tap in preceding deslagging; Greatly shorten smelting cycle, the average period of production shortened to 25 minutes by former 35 minutes, effectively reduced iron and steel stock consumption simultaneously; Improve the converter lining life-span, realize the low cost of dephosphorization stove smelting half steel, high-level efficiency; The productive target of energy-conserving and environment-protective, and do not influence environment and reach half steel chemical ingredients and temperature requirement.
Embodiment
Dephosphorization furnace pressure slag provided by the invention agent is a base with the coal dust, and said coal dust is a steam coal, quality percentage composition Mt≤20% of the full water of said coal dust, the quality percentage composition 20%≤V of the volatile matter of said coal dust combustible basis
Daf≤40%, the particle diameter of coal dust be 30mm to 50mm, and the compacting balling-up.In this embodiment; In conjunction with the characteristics and the molten iron condition of 300t dephosphorization converter, converter oxygen supply intensity, oxygen lance position; Situation such as oxygen consumption and auxiliary material adding; Add the pressure slag provided by the invention agent of Different Weight, can the full iron of dephosphorization converter finishing slag be controlled at below 10%, and the realization converter is tapped fast.
After the dephosphorization converter is adorned steel scrap and converted the iron operation, operate according to control of corresponding rifle position and feed pattern, 8-11 ℃ of control converter temperature reduction, every stove is added the about 0.5-0.8 ton of agglomerate, and oxygen flow is opened to blow and is 30000-35000Nm early stage
3/ h opens to blow after 2-3 minute and is adjusted into 20000-25000Nm
3/ h was until finishing blowing oxygen supply time 5-6 minute.Finishing blowing is carried rifle, carries adding said pressure slag agent 200-300kg behind the rifle, if molten iron silicon content is higher, can be in two batches time adds, and need not preceding deslagging after the adding, directly converter is shaken to stove and taps.
Embodiment 1
Smelt half steel; Going into stove steel scrap weight is 25.85 tons, 295.2 tons of weight of molten iron, molten iron C content 4.33%, Si content 0.26%, S content 0.001%, P content 0.0793%, Mn content 0.0201%, 1344 ℃ of molten iron temperatures.
Operation scheme: this heat stays 3 tons of the quantity of slag, adds the decarburization stove and returns 6 tons of slags, and lime adds 3.0 tons, 1.02 tons of light-burned addings, and agglomerate adds 3.92 tons, and cooled agglomerated pellet adds 3.0 tons, and fluorite adds 0.502 ton.Converter oxygen gun adds said pressure slag agent 245kg after carrying rifle, the deslagging operation before need not tapping, directly tapping.Converter can be avoided the preceding deslagging (88 ℃ at converter inclination angle) of converter after adopting this methodology, taps and directly shake to stove.
The terminal point situation: terminal point C is 3.42%, and P is 0.0323%, and temperature is 1346 ℃; Terminal point control is good, all hits, dephosphorization rate 59.3%.
Case study on implementation 2
Smelt half steel: going into stove steel scrap weight is 25.59 tons, and weight of molten iron is 296.19 tons, and molten iron C content is 4.36%, and Si content is 0.46%, and P content is 0.085%, and Mn content is 0.24%, and S content is 0.002%, and molten iron temperature is 1360 ℃.
Operation scheme: this heat stays 3 tons of the quantity of slag, adds the decarburization stove and returns 6 tons of slags, and lime adds 5.639 tons, 2.271 tons of light-burned addings, and agglomerate adds 9.69 tons, and cooled agglomerated pellet adds 6.122 tons, and fluorite adds 0.285 ton.Converter oxygen gun adds said pressure slag agent 238kg after carrying rifle, the deslagging operation before need not tapping, directly tapping.
The terminal point situation: terminal point C is 3.49%, and P is 0.027%, and temperature is 1343 ℃, TFe10.7% in the slag, and terminal point control is good, all hits, dephosphorization rate 68.2%.
The present invention uses coal to press the slag agent as steel-making, and through reducing finishing slag FeO content, dephosphorization is smelted need not just can directly tap in preceding deslagging, greatly shortens smelting cycle, and the average period of production shortened to 25 minutes by former 35 minutes; Effectively reduce iron and steel stock consumption, improve the converter lining life-span, realize the low cost of dephosphorization stove smelting half steel, high-level efficiency, the productive target of energy-conserving and environment-protective, and do not influence environment and reach half steel chemical ingredients and temperature requirement.
It should be noted last that; Above embodiment is only unrestricted in order to technical scheme of the present invention to be described; Although with reference to instance the present invention is specified, those of ordinary skill in the art should be appreciated that and can make amendment or be equal to replacement technical scheme of the present invention; And not breaking away from the spirit and the scope of technical scheme of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.
Claims (8)
1. coal is pressed the purposes of slag agent as steel-making.
2. coal as claimed in claim 1 is characterized in that: it is characterized in that as the purposes of steel-making pressure slag agent: this pressure slag agent is base with the coal dust.
3. according to claim 1 or claim 2 coal is pressed the purposes of slag agent as steel-making, and it is characterized in that: said coal dust is a steam coal.
4. like the purposes of each described coal of claim 1 to 3 as the agent of steel-making pressure slag, it is characterized in that: the quality percentage composition of the full water of said coal dust is below 20%.
5. like the purposes of each described coal of claim 1 to 4 as the agent of steel-making pressure slag, it is characterized in that: the quality percentage composition of the combustible basis volatile matter of said coal dust is more than 20%, below 40%.
6. like the purposes of each described coal of claim 1 to 5 as the agent of steel-making pressure slag, it is characterized in that: the particle diameter of said coal dust is that 30mm is to 50mm.
7. one kind is suppressed the method that slag steeps, and it is characterized in that: control converter temperature reduces 8-11 ℃, and every stove is added about 0.5 to 0.8 ton of refrigerant, and oxygen supply is opened and blown 30000-35000Nm in early stage
3/ h opens to blow after 2-3 minute and is adjusted into 20000-25000Nm
3/ h is until finishing blowing; After the dephosphorization finishing blowing, in converter, add like each said pressure slag agent of claim 1 to 6.
8. the method for inhibition slag bubble as claimed in claim 7, it is characterized in that: said refrigerant is an agglomerate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103171898A CN102787201A (en) | 2012-08-31 | 2012-08-31 | Application of coal as steelmaking slag pressing agent and method for inhibiting steel slag foaming |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103171898A CN102787201A (en) | 2012-08-31 | 2012-08-31 | Application of coal as steelmaking slag pressing agent and method for inhibiting steel slag foaming |
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|---|---|
| CN102787201A true CN102787201A (en) | 2012-11-21 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2012103171898A Pending CN102787201A (en) | 2012-08-31 | 2012-08-31 | Application of coal as steelmaking slag pressing agent and method for inhibiting steel slag foaming |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104878161A (en) * | 2014-02-28 | 2015-09-02 | 上海梅山钢铁股份有限公司 | Slag pressing agent for converter slag tank, and preparation method thereof |
| CN105132613A (en) * | 2015-09-25 | 2015-12-09 | 唐山不锈钢有限责任公司 | Application of coal gangue used as converter slag inhibiting agent, and converter slag inhibiting method |
| CN106755739A (en) * | 2016-11-22 | 2017-05-31 | 首钢京唐钢铁联合有限责任公司 | Dephosphorizing slag pressing agent and method for inhibiting steel slag foaming by same |
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| CN87100551A (en) * | 1987-02-12 | 1988-08-31 | 冶金工业部钢铁研究总院 | Coal-oxygen composite blow technology for oxygen converter |
| US4792352A (en) * | 1986-01-20 | 1988-12-20 | Nippon Kokan Kabushiki Kaisha | Method for manufacturing steel through smelting reduction |
| JPH01201408A (en) * | 1988-02-08 | 1989-08-14 | Nkk Corp | Slopping inhibitor for steelmaking |
| US5480473A (en) * | 1992-10-16 | 1996-01-02 | Technological Resources Pty. Limited | Method for intensifying the reactions in metallurgical reaction vessels |
| CN101487069A (en) * | 2008-01-18 | 2009-07-22 | 上海梅山钢铁股份有限公司 | Foam slag inhibitor for converter |
| CN101857911A (en) * | 2010-07-16 | 2010-10-13 | 四川省达州钢铁集团有限责任公司 | Method for steelmaking by using converter |
| CN102230052A (en) * | 2011-07-19 | 2011-11-02 | 莱芜钢铁股份有限公司 | Top-bottom combined blowing converter technology for high-carbon low-phosphor molten steel with single-slag process |
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2012
- 2012-08-31 CN CN2012103171898A patent/CN102787201A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4792352A (en) * | 1986-01-20 | 1988-12-20 | Nippon Kokan Kabushiki Kaisha | Method for manufacturing steel through smelting reduction |
| CN87100551A (en) * | 1987-02-12 | 1988-08-31 | 冶金工业部钢铁研究总院 | Coal-oxygen composite blow technology for oxygen converter |
| JPH01201408A (en) * | 1988-02-08 | 1989-08-14 | Nkk Corp | Slopping inhibitor for steelmaking |
| US5480473A (en) * | 1992-10-16 | 1996-01-02 | Technological Resources Pty. Limited | Method for intensifying the reactions in metallurgical reaction vessels |
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| CN102230052A (en) * | 2011-07-19 | 2011-11-02 | 莱芜钢铁股份有限公司 | Top-bottom combined blowing converter technology for high-carbon low-phosphor molten steel with single-slag process |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104878161A (en) * | 2014-02-28 | 2015-09-02 | 上海梅山钢铁股份有限公司 | Slag pressing agent for converter slag tank, and preparation method thereof |
| CN105132613A (en) * | 2015-09-25 | 2015-12-09 | 唐山不锈钢有限责任公司 | Application of coal gangue used as converter slag inhibiting agent, and converter slag inhibiting method |
| CN105132613B (en) * | 2015-09-25 | 2017-10-10 | 唐山不锈钢有限责任公司 | The application and converter that gangue presses down slag agent as converter press down the method for slag |
| CN106755739A (en) * | 2016-11-22 | 2017-05-31 | 首钢京唐钢铁联合有限责任公司 | Dephosphorizing slag pressing agent and method for inhibiting steel slag foaming by same |
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Application publication date: 20121121 |