CN101049629A - Method for preparing continuous casting protecting slag by using continuous casting sheet iron slag - Google Patents
Method for preparing continuous casting protecting slag by using continuous casting sheet iron slag Download PDFInfo
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- CN101049629A CN101049629A CN 200710052192 CN200710052192A CN101049629A CN 101049629 A CN101049629 A CN 101049629A CN 200710052192 CN200710052192 CN 200710052192 CN 200710052192 A CN200710052192 A CN 200710052192A CN 101049629 A CN101049629 A CN 101049629A
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Abstract
A process for preparing the protecting slag of conticasting from the oxidized iron scales of conticasting includes such steps as magnetically separating the oxidized iron scales whose content of TFe is 60-72% from the residual protecting slag whose content of TFe is less than 3%, proportionally mixing said residual protecting slag with assistant chosen from wallastonite, lime stone, fluorite, quartz, sodium carbonate and borax, adding carbon material, and stirring.
Description
Technical field
The present invention relates to the comprehensive utilization of the final waste material continuous casting iron sheet slag of producing of continuous casting of molten steel production technology, refer to a kind of method of utilizing continuous casting iron sheet slag to prepare continuous casting covering slag particularly.
Background technology
Continuous casting iron sheet slag is the mixture of the residue that produces of the used continuous casting covering slag of the iron scale that produced after the continuous casting billet oxidation by air and continuous cast mold.Continuous casting covering slag is indispensable auxiliary material in the continuous casting of molten steel process, and it is added in the molten steel surface in the continuous cast mold, plays a part to prevent molten steel oxidation and lubricated steel billet after its fusing.After steel billet went out continuous cast mold, continuous casting covering slag is swept away from steel billet by cooling water became the covering slag residue.Meanwhile, high temperature billet steel loses the protection of continuous casting covering slag, directly contacts with the cooling water and air, and its surface is oxidized to the oxide of iron, i.e. iron scale inevitably.Under conticaster, iron scale and covering slag residue are poured a detritus tank together.
As the requisite auxiliary material of continuous casting process, the composition of continuous casting covering slag, performance requirement are very strict.For the ease of controlling its composition and performance, continuous casting covering slag all is to produce with the mineral matter (lime stone, fluorite, quartz, graphite etc.) of ingredient stability and chemical industry material (clinker, soda ash, borax, carbon black etc.).The present preliminary melting type continuous casting covering slag that generally uses; especially several raw materials are mixed back high temperature melting, shrend, the levigate fritting material that becomes; again according to the performance requirement of various covering slags; in pre-melt, allocating suitable raw mineral materials into and adjusting composition, performance, and allocating carbonaceous material into and produce the preliminary melting type continuous casting covering slag.Like this, its cost is very high, about 1700 yuan/ton of the price of at present pre-melt.
The consumption of continuous casting covering slag is also very big in the continuous casting of molten steel production technology, and steel per ton needs 0.4～0.7 kilogram approximately.By its final formed waste material continuous casting iron sheet slag is carried out sample analysis, find that the covering slag residue in the continuous casting iron sheet slag accounts for 20～40%, iron scale accounts for 60～80%.Owing to contain low melting point such as Na in the continuous casting iron sheet slag
2O, K
2O, CaF
2, B
2O
3Deng, for twice laid, some producer is its sintering aid as pellet at present, perhaps directly as the raw material of pellet.But these low melting points are Na particularly
2O and K
2O is extremely harmful to blast furnace, causes the fire door dross easily, and international standard requires Na in the pellet
2O+K
2O must be lower than 0.35%, so these continuous casting iron sheet slag waste materials and be not suitable for pellet.Therefore, a lot of steel plant only sell as leftover bits and pieces the continuous casting iron sheet slag that produces in the casting process with extremely low price.
Summary of the invention
Purpose of the present invention is exactly the deficiency that will solve the above-mentioned background technology, proposes a kind of method of utilizing continuous casting iron sheet slag to prepare continuous casting covering slag.Adopt this method to produce continuous casting covering slag, can reclaim the discarded object that produces in the continuous casting production process to greatest extent, make it effectively to be fully utilized, and then significantly reduce the production cost of continuous casting steel billet.
For achieving the above object, the continuous casting iron sheet slag that utilizes that the present invention is designed prepares the method for continuous casting covering slag, in turn includes the following steps:
1) is raw material with the final formed waste material continuous casting iron sheet slag of continuous casting of molten steel production technology, adopts magnetic selection method that it is separated, be divided into TFe content and be 60～72% iron scale and TFe content less than 3% covering slag residue.In the isolated iron scale of institute, Na
2O＜0.35% can be used as iron-making and steel-making raw material, SiO
2＜0.5% can be used as magnetic material, iron powder material.Isolated covering slag residue, its chemical analysis is the same substantially with common slab covering slag, and its hemisphere point, viscosity are also very approaching, only need allocate a certain amount of other auxiliary material into, just can adjust its physicochemical property, so used as the continuous casting covering slag raw material.
2) get 50～98% covering slag residue by weight; allocate 0～48% auxiliary material into; auxiliary material is one or more the combination in wollastonite, lime stone, fluorite, quartz, sodium carbonate, the borax; add 2～20% carbonaceous material again; fully mix, can obtain the required continuous casting covering slag of continuous casting of molten steel production technology.
Further, in the said step 1), adopting earlier magnetic field intensity successively is that the first leg magnetic separation is directly carried out to continuous casting iron sheet slag in the low-intensity magnetic field of 1000～1500Oe and middle magnetic field that magnetic field intensity is 1500～10000Oe, isolates a part of iron scale and covering slag residue; To become granularity to account for iron sheet slag ore pulp more than 80% with wet grinding through the tailings of first leg magnetic separation then less than the particle of 0.07mm; Adopt low-intensity magnetic field and the middle magnetic field corresponding that iron sheet slag ore pulp is carried out the second leg magnetic separation more successively, isolate remaining iron scale and covering slag residue with above-mentioned magnetic field intensity.Through two magnetic separation that bout is meticulous; can to greatest extent continuous casting iron sheet slag be separated into iron scale and covering slag residue two parts; guarantee that particularly the isolated covering slag residue TFe content of institute less than 3%, so just is suitable for the raw material as continuous casting covering slag.
Further; said step 2) in; auxiliary material adopts the combination of quartz, fluorite and sodium carbonate; carbonaceous material adopts carbon powder or graphite powder; the preferable weight proportion of each component is: covering slag residue 70～85%; quartz 3～10%, fluorite 1～4%, sodium carbonate 1～6%, carbon powder or graphite powder 2～10%.The optimum weight proportioning of each component is: covering slag residue 85%, quartz 5%, fluorite 2%, sodium carbonate 3%, carbon powder or graphite powder 5%.These auxiliary materials are cheap, wide material sources, stable performance, be easy to obtain, and can significantly improve the cost performance of continuous casting covering slag.
The invention has the advantages that: designed method at first is separated into iron scale and covering slag residue by magnetic separation with continuous casting iron sheet slag effectively, can isolated iron scale be reclaimed as the Ferrous Metallurgy raw material or as the raw material of producing iron powder and magnetic material according to the character of iron scale on the one hand; Can give full play to covering slag residue and continuous casting covering slag on the other hand in chemical analysis and essentially identical in nature characteristics, utilize the raw material of covering slag residue as the preparation continuous casting covering slag.Thereby greatly increased the comprehensive utilization ratio of continuous casting iron sheet slag, the resources costs of significantly having saved continuous casting manufacturing technique has also greatly reduced the production cost of continuous casting steel billet.
Description of drawings
Accompanying drawing is for to carry out two bout magnetic separation separation processes flow charts to the continuous casting iron sheet slag raw material among the preparation method of the present invention.
The specific embodiment
Below in conjunction with the drawings and specific embodiments preparation method of the present invention is described in further detail:
Embodiment 1:
The waste material continuous casting iron sheet slag that is produced with Wuhan Iron ﹠ Steel's the 3rd steel mill continuous casting of molten steel production technology is a raw material, and preparation method of the present invention in turn includes the following steps:
Step 1): get above-mentioned continuous casting iron sheet slag, it is carried out magnetic separation separate.Concrete operation method as shown in drawings; at first adopting magnetic field intensity is the low-intensity magnetic field of 1000～1500Oe; a part of iron scale in the continuous casting iron sheet slag is just branched away; next adopts magnetic field intensity is the middle magnetic field of 1500～10000Oe; a part of covering slag residue in the continuous casting iron sheet slag is just branched away, finish the magnetic separation of first leg.Learnt from else's experience the then tailings of first leg magnetic separation, wet grinding mill is fine into iron sheet slag ore pulp in the self-overflow type ball mill, and granularity should account for more than 80% less than the particle of 0.07mm in the iron sheet slag ore pulp.Get levigate iron sheet slag ore pulp again, repeat the magnetic separation operation in above-mentioned low-intensity magnetic field and middle magnetic field, finish second leg magnetic separation, iron scale and covering slag residue in the continuous casting iron sheet slag are separated fully iron sheet slag ore pulp.
Through Instrumental Analysis, chemical analysis (%), ratio and the physical property of above-mentioned continuous casting iron sheet slag and iron scale that is separated and covering slag residue are as shown in table 1:
Table 1:
| SiO 2 | Al 2O 3 | CaO | F | Na 2O | TFe | The hemisphere point (℃) | Viscosity (pool, 1300 ℃) | Ratio (%) | |
| The iron sheet slag | 6.16 | 1.32 | 7.4 | 1.45 | 59.79 | ||||
| The covering slag residue | 29.98 | 6.71 | 35.48 | 6.21 | 8.24 | 2.86 | 1097 | 2.1 | 15.7 |
| Iron scale | 2.48 | 0.46 | 1.47 | 0.4 | 0.25 | 71.38 | 68.2 | ||
| Tailings | 14.1 |
In the analysis result, the ratio total amount of each chemical analysis is 98%, less than 100% shown in the table 1.The residue component is oxygen element, impurity and the volatile matter loss in the iron oxide, does not count.As seen from Table 1, Na in the continuous casting iron sheet slag
2The content of O is 1.45%, is to be not suitable for making the pellet that is used for blast furnace process.Iron scale after the separation, its TFe content is 71.38%, Na
2O content is 0.25% only, is lower than required standard value 0.35%, compares with common iron ore, and it is that its T Fe is far above common iron ore, and ingredient stability, objectionable impurities S, P, SiO through the steelmaking process high ferro component that oxidation produces on continuous casting billet
2Content is extremely low, can be used for blast furnace fully and as other Ferrous Metallurgy raw material, even can produce iron powder and magnetic material.
And the covering slag residue after separating, its TFe content is 2.86%, and is the same substantially with common slab covering slag, 1097 ℃ of its hemisphere points, viscosity 2.1 pools (1300 ℃) are also approaching with common slab covering slag.Through the X-ray diffraction facies analysis, the covering slag residue that is separated is the same with the pre-melt of existing covering slag, is non-crystal structure.Thereby, only need allocate a certain amount of other auxiliary material into, just can adjust its physicochemical property, make the various different continuous casting covering slags that require.
Step 2): get above-mentioned covering slag residue 85% by weight ratio, allocate quartz 5%, fluorite 2%, sodium carbonate 3% into, add carbon powder 5%, fully mix,, can obtain the required continuous casting covering slag of continuous casting of molten steel production technology through mist projection granulating.Through check, its hemisphere point is 1050 ℃, and 1300 ℃ of viscosity are 1.7 pools, experimentize in Wuhan Iron ﹠ Steel's second steel mill Q235 plate slab continuous casting manufacturing technique, and the gained cc billet surface quality is good, does not have any bad problem and occurs.
Embodiment 2:
Its step 1) is identical with embodiment 1 to the magnetic separation separation of continuous casting iron sheet slag.Its step 2) in, by weight ratio fetch protection slag residue 80%, allocate quartzy 8%, fluorite 4%, sodium carbonate 2% into, add carbon powder 6%, fully mix, through mist projection granulating, can obtain the required continuous casting covering slag of continuous casting of molten steel production technology.
Embodiment 3:
Its step 1) is identical with embodiment 1 to the magnetic separation separation of continuous casting iron sheet slag.Its step 2) in, by weight ratio fetch protection slag residue 75%, allocate quartzy 8%, fluorite 7%, sodium carbonate 6% into, add carbon powder 4%, fully mix, through mist projection granulating, can obtain the required continuous casting covering slag of continuous casting of molten steel production technology.
Embodiment 4:
Its step 1) is identical with embodiment 1 to the magnetic separation separation of continuous casting iron sheet slag.Its step 2) in, by weight ratio fetch protection slag residue 70%, allocate quartzy 10%, lime stone 4%, sodium carbonate 6% into, add carbon powder 10%, fully mix, through mist projection granulating, can obtain the required continuous casting covering slag of continuous casting of molten steel production technology.
Embodiment 2～3 prepared continuous casting covering slags are used for the experiment of second and third steel mill Q235 of Wuhan Iron ﹠ Steel (Group) Corp. plate slab continuous casting manufacturing technique; embodiment 4 prepared continuous casting covering slags are used for square billet production; the gained cc billet surface quality is good, does not have bad problem and occurs.
Claims (6)
1. method of utilizing continuous casting iron sheet slag to prepare continuous casting covering slag in turn includes the following steps:
1) is raw material with the final formed waste material continuous casting iron sheet slag of continuous casting of molten steel production technology, adopts magnetic selection method that it is separated, be divided into TFe content and be 60～72% iron scale and TFe content less than 3% covering slag residue;
2) get 50～98% covering slag residue by weight; allocate 0～48% auxiliary material into; auxiliary material is one or more the combination in wollastonite, lime stone, fluorite, quartz, sodium carbonate, the borax; add 2～20% carbonaceous material again; fully mix, can obtain the required continuous casting covering slag of continuous casting of molten steel production technology.
2. the method for utilizing continuous casting iron sheet slag to prepare continuous casting covering slag according to claim 1; it is characterized in that: in the said step 1); earlier adopt low-intensity magnetic field and middle magnetic field directly continuous casting iron sheet slag to be carried out the first leg magnetic separation successively; isolate a part of iron scale and covering slag residue; to become iron sheet slag ore pulp with wet grinding through the tailings of first leg magnetic separation then; adopt low-intensity magnetic field and middle magnetic field that iron sheet slag ore pulp is carried out the second leg magnetic separation more successively, isolate remaining iron scale and covering slag residue.
3. the method for utilizing continuous casting iron sheet slag to prepare continuous casting covering slag according to claim 2 is characterized in that: will grind to form granularity through the tailings of first leg magnetic separation and account for iron sheet slag ore pulp more than 80% less than the particle of 0.07mm.
4. the method for utilizing continuous casting iron sheet slag to prepare continuous casting covering slag according to claim 2, it is characterized in that: the magnetic field intensity of the low-intensity magnetic field that adopts is 1000～1500Oe, adopt in the magnetic field intensity in magnetic field be 1500～10000Oe.
5. the method for utilizing continuous casting iron sheet slag to prepare continuous casting covering slag according to claim 1; it is characterized in that: said step 2); auxiliary material adopts the combination of quartz, fluorite and sodium carbonate; carbonaceous material adopts carbon powder or graphite powder; the weight proportion of each component is: covering slag residue 70～85%; quartz 3～10%, fluorite 1～4%, sodium carbonate 1～6%, carbon powder or graphite powder 2～10%.
6. the method for utilizing continuous casting iron sheet slag to prepare continuous casting covering slag according to claim 1; it is characterized in that: said step 2); auxiliary material adopts the combination of quartz, fluorite and sodium carbonate; carbonaceous material adopts carbon powder; the weight proportion of each component is: covering slag residue 85%; quartz 5%, fluorite 2%, sodium carbonate 3%, carbon powder or graphite powder 5%.
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| CNB2007100521920A CN100443216C (en) | 2007-05-17 | 2007-05-17 | Method for preparing continuous casting protecting slag by using continuous casting sheet iron slag |
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| CNB2007100521920A CN100443216C (en) | 2007-05-17 | 2007-05-17 | Method for preparing continuous casting protecting slag by using continuous casting sheet iron slag |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101433950B (en) * | 2008-12-03 | 2011-07-27 | 宜兴市振球炉料有限公司 | Method for preparing protecting residue from recovery refining slag |
| CN101637812B (en) * | 2009-08-11 | 2012-05-09 | 河南省西保冶材集团有限公司 | Small plate blank continuous casting functional protective material |
| CN103447489A (en) * | 2013-09-12 | 2013-12-18 | 武汉钢铁(集团)公司 | Method for preparing high-iron-content continuous casting mold flux for laboratory |
| CN103624227A (en) * | 2013-11-04 | 2014-03-12 | 河南通宇冶材集团有限公司 | Continuous casting crystallizer casting powder of square billet casting powder low-carbon and medium-carbon steel and production method of continuous casting crystallizer casting powder |
| CN103639380A (en) * | 2013-11-04 | 2014-03-19 | 河南通宇冶材集团有限公司 | Continuous casting used crystallizer casting powder for plate blank and preparing method thereof |
| CN104439194A (en) * | 2014-11-19 | 2015-03-25 | 北京天力创玻璃科技开发有限公司 | Anti-oxidation protective agent for composite roll |
| CN110590048A (en) * | 2019-09-20 | 2019-12-20 | 中冶东方工程技术有限公司 | Continuous casting turbid circulating water treatment equipment and method |
| CN113319258A (en) * | 2021-06-02 | 2021-08-31 | 中钢南京环境工程技术研究院有限公司 | Method for preparing fluorine-free continuous casting covering slag by using rear lithium battery sagger |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US3704744A (en) * | 1971-10-22 | 1972-12-05 | Inland Steel Co | Slag use in continuous casting of steel |
| DE4123956C2 (en) * | 1991-07-19 | 1994-07-21 | Thyssen Stahl Ag | Process and plant for producing a metal strand by casting |
| US5941295A (en) * | 1996-09-30 | 1999-08-24 | Ag Industries, Inc. | System and method for removing crystallized flux |
| CN1186864A (en) * | 1997-11-27 | 1998-07-08 | 宝山钢铁(集团)公司 | Protective slag for continuous super low carbon steel casting |
| JP3929600B2 (en) * | 1998-05-22 | 2007-06-13 | 古河機械金属株式会社 | Waste melting slag casting equipment |
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2007
- 2007-05-17 CN CNB2007100521920A patent/CN100443216C/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101433950B (en) * | 2008-12-03 | 2011-07-27 | 宜兴市振球炉料有限公司 | Method for preparing protecting residue from recovery refining slag |
| CN101637812B (en) * | 2009-08-11 | 2012-05-09 | 河南省西保冶材集团有限公司 | Small plate blank continuous casting functional protective material |
| CN103447489A (en) * | 2013-09-12 | 2013-12-18 | 武汉钢铁(集团)公司 | Method for preparing high-iron-content continuous casting mold flux for laboratory |
| CN103624227A (en) * | 2013-11-04 | 2014-03-12 | 河南通宇冶材集团有限公司 | Continuous casting crystallizer casting powder of square billet casting powder low-carbon and medium-carbon steel and production method of continuous casting crystallizer casting powder |
| CN103639380A (en) * | 2013-11-04 | 2014-03-19 | 河南通宇冶材集团有限公司 | Continuous casting used crystallizer casting powder for plate blank and preparing method thereof |
| CN103624227B (en) * | 2013-11-04 | 2016-08-17 | 河南通宇冶材集团有限公司 | A kind of square billet middle low carbon steel continuous crystallizer protecting slag and preparation method thereof |
| CN104439194A (en) * | 2014-11-19 | 2015-03-25 | 北京天力创玻璃科技开发有限公司 | Anti-oxidation protective agent for composite roll |
| CN104439194B (en) * | 2014-11-19 | 2017-02-01 | 北京天力创玻璃科技开发有限公司 | Anti-oxidation protective agent for composite roll |
| CN110590048A (en) * | 2019-09-20 | 2019-12-20 | 中冶东方工程技术有限公司 | Continuous casting turbid circulating water treatment equipment and method |
| CN113319258A (en) * | 2021-06-02 | 2021-08-31 | 中钢南京环境工程技术研究院有限公司 | Method for preparing fluorine-free continuous casting covering slag by using rear lithium battery sagger |
| CN113319258B (en) * | 2021-06-02 | 2022-11-29 | 中钢集团洛阳耐火材料研究院有限公司 | Method for preparing fluoride-free continuous casting covering slag by using used lithium battery sagger |
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