CN1995404A - Mono-slag converter process for producing high carbon low-phosphorus molten steel - Google Patents
Mono-slag converter process for producing high carbon low-phosphorus molten steel Download PDFInfo
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- CN1995404A CN1995404A CN 200610166515 CN200610166515A CN1995404A CN 1995404 A CN1995404 A CN 1995404A CN 200610166515 CN200610166515 CN 200610166515 CN 200610166515 A CN200610166515 A CN 200610166515A CN 1995404 A CN1995404 A CN 1995404A
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Abstract
The invention discloses a manufacturing method of high-carbon low-phosphor molten steel of rotary furnace in the metallurgical technical domain, which comprises the following steps: transmitting high-silicon high-phosphoric molten steel in the rotary furnace; blowing through gun-changing oxygen-changing flow operation; removing phosphor first; pouring rich phosphoric slag at blowing time; adjusting terminal temperature and terminal carbon.
Description
Technical field
The present invention relates to the metallurgical technology field, specifically refer to a kind of technology that high-carbon low-phosphorus steel is produced in converter that is adapted to.
Background technology
Converter has two kinds of tapping technology patterns when producing high carbon low-phosphorus molten steel, a kind of is the low mend carbon technology that draws, i.e. mend carbon (end point carbon is between 0.07～0.12%) more in a large number after the low-carbon (LC) tapping; Another kind is high-carbon tapping technology (end point carbon 〉=0.30%).Low catch carbon technology can guarantee lower terminal point phosphorus, suitable terminal temperature and metastable end point carbon (being stabilized between 0.07～0.12%), and its technology is comparatively stable, thereby is adopted by most steel mills.But this technology molten bath terminal point oxygen level height, its iron and steel stock consumes high, and yield of alloy is low, and the production cost height is serious to lining erosion.If adopt high-carbon tapping technology, will increase substantially end point carbon, significantly reduce molten bath terminal point oxygen, thereby reduce iron and steel stock and alloy consumption, and significantly reduce the inclusion that deoxidation alloying produces, improve the molten steel purity.But converter high-carbon tapping technology exists the dephosphorization ability, terminal temperature is on the low side and the mobile difference of finishing slag is unfavorable for difficult points such as slag splashing.When therefore converter current adopts high silicon high phosphorus hot metal to produce high carbon low-phosphorus molten steel, the low mend carbon technology that draws of many employings.Even if implement the high-carbon tapping, also adopt following two kinds of technologies usually, a kind of is earlier molten iron to be carried out the dephosphorization pre-treatment, implements the high-carbon tapping by converter again; Another kind is to adopt duplex practice to finish by two block converters, promptly by the dephosphorization of block converter elder generation, is heated up by another block converter carbon drop again.Based on the dual purpose that improves the quality and reduce cost, adopting high-carbon tapping explained hereafter high carbon low-phosphorus molten steel is very effective a kind of means, but all there is certain disadvantage in aforementioned two kinds of high-carbon tapping technology, the dephosphorization of molten iron pretreatment technology has increased the facility investment and the production cost of hot metal pretreatment greatly, and duplex practice not only the organization of production difficulty is big, and can restrict the performance of converter production capacity.
Summary of the invention
The objective of the invention is at the problems referred to above provide a kind of cost low, be convenient to before and after operation production capacity coupling, can in a block converter, be raw material, adopt single slag process to produce the converter process of high carbon low-phosphorus molten steel with high silicon high phosphorus hot metal.
Technical scheme of the present invention is: high silicon high phosphorus hot metal is sent in the top bottom blowing converter, and carried out following step:
(1) a blowing dephosphorization in early stage: 45%～55% of slag making materials total amount is added in the converter, adopt low-in the operation of blowing of high rifle position and height-middle oxygen flow, bath temperature when the control blowing finishes in earlier stage is 1350～1450 ℃, basicity of slag is between 2.0～2.5, and iron oxide content is between 9%～13%;
(2) blowing secondary dephosphorization in mid-term and deslagging: 25%～35% of slag making materials total amount is added in the converter, adopt the operation of blowing of high rifle position and low oxygen flow, mid-term is poured out 50%～60% rich phosphorus slag after the end in blowing, the bath temperature that control is blown when finishing mid-term is 1560～1600 ℃, basicity of slag is between 3.5～4.0, and iron oxide content is 12%～16%;
(3) blowing later stage dephosphorization and adjust molten bath terminal temperature and end point carbon once more: will remain in 15%～20% the slag making materials adding converter, adopt the operation of blowing of high-low rifle position and medium oxygen flow, basicity of slag when the control blowing later stage finishes is between 3.7～4.2, iron oxide content is 12%～18%, after the blowing later stage finishes, after in tapping process, carrying out the deoxidation alloying processing, promptly obtain high carbon low-phosphorus molten steel.
In the above-mentioned steps (1), said low-in high rifle position and height-middle oxygen flow be: the rifle position and the 3.0Nm that adopt 1.4m earlier
3The oxygen flow of/mint after 110～140 seconds is carried the rifle position to 1.6m, simultaneously oxygen flow is reduced to 2.8Nm
3/ mint, the said blowing time in early stage was controlled at 330～360 seconds.
In the above-mentioned steps (2), the slag making materials of said adding is the adding of in batches staggering of the batch by every crowd of 3～5kg/t, and said high rifle position and low oxygen flow are operating as: the rifle position and the 2.65Nm that adopt 1.85m
3The oxygen flow of/mint, the said blowing time in mid-term was controlled at 370～410 seconds.
In the above-mentioned steps (3), the slag making materials of said adding is the adding of in batches staggering of the batch by every crowd of 2～4kg/t, said height-in low rifle position and medium oxygen flow be operating as: the rifle position and the 2.7Nm that adopt 1.7m earlier
3The oxygen flow of/mint, tapping was depressed into 1.55m with the rifle position in preceding 30 seconds again, and the said time in blowing later stage was controlled at 100～140 seconds.
Above-mentioned steps has gone out the slag that stays behind the steel in (3), adopts the oxygen rifle to spatter slag rifle position to the slag oxygen blast again, and wherein the rifle position is 0.5～0.8m, and oxygen flow is 2.8Nm
3/ mint, oxygen supply time were controlled at 10～20 seconds.
In step (1), because blowing bath temperature in early stage is low, the quantity of slag is unsuitable excessive, will control lower basicity of slag simultaneously, makes slag active as early as possible, so that under the prerequisite of effective dephosphorization, for the middle and later periods high efficiency dephosphorating lays the first stone.
In step (2), owing to rise in blowing temperature in mid-term, decarburizing reaction is accelerated, and iron oxide content reduces, thereby need rationally join slag and guarantee that slag has enough basicity and high oxidisability, to reach the purpose of high efficiency dephosphorating.When blowing finished mid-term, phosphorus pentoxide content rose in the slag, is unfavorable for the dephosphorization in later stage that blows, thereby must operates by deslagging and reduce Vanadium Pentoxide in FLAKES total amount in the slag.
In step (3), owing to further rise at the blowing latter temperature, phosphor partition ratio is lower between the slag steel, thereby need be in guarantee high basicity of slag and hyperoxia voltinism with addition of enough slag charges again after the deslagging operation, thereby reach further dephosphorization, obtain the purpose of low terminal point phosphorus by step (2).
The present invention is by the effective dephosphorization of blowing early stageization slag, blow and remove rich phosphorus slag mid-term behind the high efficiency dephosphorating, the blowing later stage carries out dephosphorization again and adjusts terminal temperature and end point carbon, the tapping back adopts the oxygen rifle to spatter slag rifle position to the slag oxygen blast, solved the dephosphorization ability, terminal temperature is on the low side and the mobile difference of finishing slag is unfavorable for difficult points such as slag splashing, the high carbon low-phosphorus molten steel of being produced is compared with the high carbon low-phosphorus molten steel that traditional method obtains, it is bessemerized end point carbon and rises to 0.3%～0.8% by 0.07%～0.12%, the terminal point oxygen level is reduced to about 100ppm about by 350ppm, terminal point phosphorus is less than 0.015%, its iron and steel stock, cost consumptions such as alloy all significantly reduce, the smelting cost of high carbon low-phosphorus molten steel reduces by 26 yuan of/ton steel approximately, and terminal temperature is up to 1640～1660 ℃, make high carbon low-phosphorus molten steel reduce by 12 yuan of/ton steel approximately, promptly reduced production cost in the smelting cost of back operation (ladle refining furnace); Converting process is all carried out in a converter simultaneously, the deslagging operation also has only 1 time, the high carbon low-phosphorus molten steel of producing is when having above-mentioned advantage, do not increase the organization of production difficulty, make the production capacity of converter, ladle refining furnace and continuous casting working procedure reach coupling, thereby this technology is suitable for large-scale promotion application.
Embodiment
The invention will be further described below in conjunction with embodiment.
Embodiment: high silicon high phosphorus hot metal is sent in the top bottom blowing converter, and carried out following step:
(1) a blowing dephosphorization in early stage: 45%～55% of slag making materials total amount is added in the converter, when blowing, adopt low rifle position and the molten steel 3.0Nm per ton of 1.4m earlier
3The operation of blowing of the oxygen flow of/min to strengthen stirring intensity of molten pool, after 110～140 seconds is carried the rifle position to 1.7m, simultaneously oxygen flow is reduced to molten steel 2.6Nm per ton
3/ min, so that reduce blowing heat-up rate in early stage, guarantee effective dephosphorization in early stage, and lay the first stone for the middle and later periods high efficiency dephosphorating, time in blowing early stage is the shortest to be no less than 330 seconds, and no longer than 360 seconds, the bath temperature when the control blowing finishes early stage was 1350～1450 ℃, basicity of slag is between 2.0～2.5, and iron oxide content is between 9%～13%;
(2) blowing secondary dephosphorization in mid-term and deslagging: 25%～35% of slag making materials total amount is added in the converter, and by the batch of every crowd of molten steel 3～5kg per ton with slag making materials addings of staggering, rifle position and the molten steel 2.65Nm per ton of employing 1.85m in batches
3The operation of blowing of the oxygen flow of/min, the blowing time in mid-term the shortlyest is no less than 370 seconds, no longer than 410 seconds, pour out 50%～60% rich phosphorus slag after the end, and get the steel sample and determine that for the later stage duration of blast provides foundation, the bath temperature that control is blown when finishing mid-term is 1560～1600 ℃, and basicity of slag is between 3.5～4.0, and iron oxide content is between 12%～16%;
(3) blowing later stage dephosphorization and adjust molten bath terminal temperature and end point carbon once more: will remain in 15%～20% the slag making materials adding converter, and by the adding of staggering of the batch of every crowd of molten steel 2～4kg per ton in batches, when blowing, adopt rifle position and the molten steel 2.7Nm per ton of 1.7m earlier
3The oxygen flow of/min, tap and again the rifle position was forced down to 1.55m in preceding 30 seconds, wherein, basicity of slag when the control blowing later stage finishes is between 3.7～4.2, and iron oxide content is between 10%～15%, and institute's steel sample of getting determines that the blowing time in mid-term the shortlyest is no less than 110 seconds when finishing mid-term according to blowing, no longer than 140 seconds, after the blowing later stage finishes, in tapping process, carry out promptly obtaining high carbon low-phosphorus molten steel after deoxidation alloying handles.After tapping, pass through to adopt rifle position and the molten steel 2.8Nm per ton of 0.5～0.8m
3The oxygen flow of/min to improve slag fluidity, is guaranteed the slag splashing effect to slag oxygen blast 10～20 seconds.
Adopt processing method of the present invention, can make end point carbon reach 0.3%～0.8%, terminal point oxygen is about 100ppm, and terminal point phosphorus is less than 0.015%.Terminal temperature reaches 1640～1660 ℃.
Claims (5)
1, a kind of single slag process is produced the converter process of high carbon low-phosphorus molten steel, it is characterized in that, high silicon high phosphorus hot metal is sent in the converter, and carried out following step:
(1) a blowing dephosphorization in early stage: 45%～55% of slag making materials total amount is added in the converter, adopt low-in the operation of blowing of high rifle position and height-middle oxygen flow, bath temperature when the control blowing finishes in earlier stage is 1350～1450 ℃, basicity of slag is between 2.0～2.5, and iron oxide content is between 9%～13%;
(2) blowing secondary dephosphorization in mid-term and deslagging: 25%～35% of slag making materials total amount is added in the converter, adopt the operation of blowing of high rifle position and low oxygen flow, mid-term is poured out 50%～60% rich phosphorus slag after the end in blowing, the bath temperature that control is blown when finishing mid-term is 1560～1600 ℃, basicity of slag is between 3.5～4.0, and iron oxide content is 12%～16%;
(3) blowing later stage dephosphorization and adjust molten bath terminal temperature and end point carbon once more: will remain in 15%～20% the slag making materials adding converter, adopt the operation of blowing of high-low rifle position and medium oxygen flow, basicity of slag when the control blowing later stage finishes is between 3.7～4.2, iron oxide content is 12%～18%, after the blowing later stage finishes, after in tapping process, carrying out the deoxidation alloying processing, promptly obtain high carbon low-phosphorus molten steel.
2, single slag process as claimed in claim 1 is produced the converter process of high carbon low-phosphorus molten steel, it is characterized in that, in the step (1), said low-in high rifle position and height-middle oxygen flow be: rifle position and the 3.0Nm of first employing 1.4m
3The oxygen flow of/mint after 120～150 seconds is carried the rifle position to 1.6m, simultaneously oxygen flow is reduced to 2.8Nm
3/ mint, the said blowing time in early stage was controlled at 330～360 seconds.
3, single slag process as claimed in claim 1 is produced the converter process of high carbon low-phosphorus molten steel, it is characterized in that, in the step (2), the slag making materials of said adding is the adding of in batches staggering of the batch by every crowd of 3～5kg/t, and said high rifle position and low oxygen flow are operating as: the rifle position and the 2.65Nm that adopt 1.85m
3The oxygen flow of/mint, the said blowing time in mid-term was controlled at 370～410 seconds.
4, single slag process as claimed in claim 1 is produced the converter process of high carbon low-phosphorus molten steel, it is characterized in that, in the step (3), the slag making materials of said adding is the adding of in batches staggering of the batch by every crowd of 2～4kg/t, said height-in low rifle position and medium oxygen flow be operating as: the rifle position and the 2.7Nm that adopt 1.7m earlier
3The oxygen flow of/mint, tap preceding 30 seconds again with the rifle potential drop to 1.55m, the said time in blowing later stage was controlled at 100～140 seconds.
5, produce the converter process of high carbon low-phosphorus molten steels as claim 1 or 4 described single slag process, it is characterized in that,, adopt the oxygen rifle again to spatter slag rifle position to the slag oxygen blast to having gone out the slag that stays behind the steel in the step (3), wherein the rifle position is 0.5～0.8m, and oxygen flow is 2.8Nm
3/ mint, oxygen supply time were controlled at 10～20 seconds.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006101665154A CN100453657C (en) | 2006-12-28 | 2006-12-28 | Mono-slag converter process for producing high carbon low-phosphorus molten steel |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006101665154A CN100453657C (en) | 2006-12-28 | 2006-12-28 | Mono-slag converter process for producing high carbon low-phosphorus molten steel |
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| CN1995404A true CN1995404A (en) | 2007-07-11 |
| CN100453657C CN100453657C (en) | 2009-01-21 |
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| CNB2006101665154A Expired - Fee Related CN100453657C (en) | 2006-12-28 | 2006-12-28 | Mono-slag converter process for producing high carbon low-phosphorus molten steel |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN102747182A (en) * | 2012-06-14 | 2012-10-24 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Method for producing high-carbon steel by applying high-carbon-catch single-slag method through 50t top blast converter |
| CN103060511A (en) * | 2013-01-14 | 2013-04-24 | 攀钢集团攀枝花钢铁研究院有限公司 | Oxygen supply method for preventing dedusting explosion venting of semisteel steel converter and semisteel smelting method |
| CN103060509A (en) * | 2012-03-31 | 2013-04-24 | 上海梅山钢铁股份有限公司 | High-silicon molten iron smelting method |
| CN103266195A (en) * | 2013-05-15 | 2013-08-28 | 武汉钢铁(集团)公司 | Method for improving smelting dephosphorization of converter |
| CN104561433A (en) * | 2014-12-24 | 2015-04-29 | 山东钢铁股份有限公司 | Converter smelting method of medium-high carbon and ultra-low phosphorus molten steel |
| CN104878153A (en) * | 2015-05-22 | 2015-09-02 | 河北钢铁股份有限公司邯郸分公司 | Converter dephosphorization method for high-phosphorus low-silicon molten iron |
| CN104911295A (en) * | 2015-06-08 | 2015-09-16 | 北京科技大学 | Converter low-slag-added smelting method |
| CN105132611A (en) * | 2015-09-29 | 2015-12-09 | 山东钢铁股份有限公司 | Method for producing ultra-low phosphorous steel through single slag of converter |
| CN107779540A (en) * | 2016-08-31 | 2018-03-09 | 鞍钢股份有限公司 | A kind of converter list slag melting method of high-silicon molten iron |
| CN109022670A (en) * | 2018-07-20 | 2018-12-18 | 首钢集团有限公司 | A kind of converter steel making method producing ultra-low phosphoretic steel |
| CN113293260A (en) * | 2021-04-27 | 2021-08-24 | 宁夏钢铁(集团)有限责任公司 | Efficient dephosphorization process method using fly ash as converter slagging agent |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| DE3931024C1 (en) * | 1989-09-16 | 1991-05-16 | Krupp Stahl Ag, 4630 Bochum, De | Steel prodn. having low phosphor content - comprises single stage process using calcium oxide saturated residual stage from porous melt |
| JPH11343514A (en) * | 1998-06-02 | 1999-12-14 | Kawasaki Steel Corp | Method for melting high carbon steel using bottom-blown converter |
| CN100354433C (en) * | 2006-02-21 | 2007-12-12 | 攀钢集团成都钢铁有限责任公司 | Converter smelting method |
-
2006
- 2006-12-28 CN CNB2006101665154A patent/CN100453657C/en not_active Expired - Fee Related
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
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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 |
| CN102230052B (en) * | 2011-07-19 | 2015-01-21 | 山东钢铁股份有限公司 | Top-bottom combined blowing converter technology for high-carbon low-phosphor molten steel with single-slag process |
| CN103060509B (en) * | 2012-03-31 | 2015-03-18 | 上海梅山钢铁股份有限公司 | High-silicon molten iron smelting method |
| CN103060509A (en) * | 2012-03-31 | 2013-04-24 | 上海梅山钢铁股份有限公司 | High-silicon molten iron smelting method |
| CN102747182A (en) * | 2012-06-14 | 2012-10-24 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Method for producing high-carbon steel by applying high-carbon-catch single-slag method through 50t top blast converter |
| CN103060511A (en) * | 2013-01-14 | 2013-04-24 | 攀钢集团攀枝花钢铁研究院有限公司 | Oxygen supply method for preventing dedusting explosion venting of semisteel steel converter and semisteel smelting method |
| CN103060511B (en) * | 2013-01-14 | 2014-07-09 | 攀钢集团攀枝花钢铁研究院有限公司 | Oxygen supply method for preventing dedusting explosion venting of semisteel steel converter and semisteel smelting method |
| CN103266195B (en) * | 2013-05-15 | 2015-12-23 | 武汉钢铁(集团)公司 | A kind of method improving converter smelting dephosphorization |
| CN103266195A (en) * | 2013-05-15 | 2013-08-28 | 武汉钢铁(集团)公司 | Method for improving smelting dephosphorization of converter |
| CN104561433A (en) * | 2014-12-24 | 2015-04-29 | 山东钢铁股份有限公司 | Converter smelting method of medium-high carbon and ultra-low phosphorus molten steel |
| CN104878153A (en) * | 2015-05-22 | 2015-09-02 | 河北钢铁股份有限公司邯郸分公司 | Converter dephosphorization method for high-phosphorus low-silicon molten iron |
| CN104911295A (en) * | 2015-06-08 | 2015-09-16 | 北京科技大学 | Converter low-slag-added smelting method |
| CN104911295B (en) * | 2015-06-08 | 2017-07-18 | 北京科技大学 | The smelting process that a kind of converter less-slag material is added |
| CN105132611A (en) * | 2015-09-29 | 2015-12-09 | 山东钢铁股份有限公司 | Method for producing ultra-low phosphorous steel through single slag of converter |
| CN105132611B (en) * | 2015-09-29 | 2017-04-19 | 山东钢铁股份有限公司 | Method for producing ultra-low phosphorous steel through single slag of converter |
| CN107779540A (en) * | 2016-08-31 | 2018-03-09 | 鞍钢股份有限公司 | A kind of converter list slag melting method of high-silicon molten iron |
| CN109022670A (en) * | 2018-07-20 | 2018-12-18 | 首钢集团有限公司 | A kind of converter steel making method producing ultra-low phosphoretic steel |
| CN113293260A (en) * | 2021-04-27 | 2021-08-24 | 宁夏钢铁(集团)有限责任公司 | Efficient dephosphorization process method using fly ash as converter slagging agent |
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