CN103924025A - Method for pre-desulfuration of combined-blowing molten iron at top and bottom in ladle - Google Patents

Method for pre-desulfuration of combined-blowing molten iron at top and bottom in ladle Download PDF

Info

Publication number
CN103924025A
CN103924025A CN201410118031.7A CN201410118031A CN103924025A CN 103924025 A CN103924025 A CN 103924025A CN 201410118031 A CN201410118031 A CN 201410118031A CN 103924025 A CN103924025 A CN 103924025A
Authority
CN
China
Prior art keywords
powder
molten iron
bottom blowing
hot metal
blowing
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.)
Granted
Application number
CN201410118031.7A
Other languages
Chinese (zh)
Other versions
CN103924025B (en
Inventor
罗志国
董建
李林蔚
梁义会
游洋
顾克井
刘志兴
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Northeastern University China
Tangshan Guofeng Iron and Steel Co Ltd
Original Assignee
Northeastern University China
Tangshan Guofeng Iron and Steel Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Northeastern University China, Tangshan Guofeng Iron and Steel Co Ltd filed Critical Northeastern University China
Priority to CN201410118031.7A priority Critical patent/CN103924025B/en
Publication of CN103924025A publication Critical patent/CN103924025A/en
Application granted granted Critical
Publication of CN103924025B publication Critical patent/CN103924025B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Abstract

The invention relates to a method for pre-desulfuration of a combined-blowing molten iron at the top and bottom in a ladle. The method is characterized in that equipment applied to the method mainly comprises a top-blowing powder spraying tank, a bottom-blowing powder spraying tank, the ladle, a top-blowing spraying gun and a bottom-blowing ventilation element. According to the equipment, various spraying and blowing parameters and the spraying-in quantity of desulfurizing agents such as magnesium powder are controlled, so that compared with the single top-blowing process under the same carrier gas flow, the method provided by the invention has the advantages that the even mixing time is shortened by 15-20%, and the magnesium powder is saved by 0.20-0.30kg in each ton of molten iron.

Description

A kind of method of top and bottom complex blowing molten iron pre-desulfurization in hot metal ladle
Technical field
The invention belongs to metallurgical technology field, be specifically related to a kind of method of pre-desulfuration of molten iron in foundry ladle.
Background technology
Along with modern industry is produced and scientific and technical developing rapidly, the requirement of steel product quality is improved day by day.Produce low-sulfur steel and ultralow-sulfur steel and need adopt molten iron pre-desulfurization technique, and molten iron pre-desulfurization has become one of indispensable operation of optimizing metallurgical production technique.
The Desulphuring Process of Molten Iron of having realized at present suitability for industrialized production mainly can be divided into mechanical mixing method desulfurization (KR) and two kinds of methods of top spray method desulfurization, also has in addition preindustrial hot metal ladle bottom blowing powder injection sulfur method.
KR paddling process is to utilize agitator to enter rotation in hot metal ladle to stir molten iron, adds sweetening agent to make it be involved in the inner fully reaction of molten iron simultaneously, thereby reaches the object of desulfurizing iron.The method reacting dynamics condition is good, and desulfurizing iron efficiency is high; Shortcoming is that hot metal temperature drop is large, invests high.
Top spray method is to utilize rare gas element as current-carrying gas, by desulfurization powder (as CaO, CaC 2and Mg) by spray gun, sprayed in molten iron, blowing gas, sweetening agent and molten iron three are fully mixed and carry out desulfurization.Blowing process is the molten iron pre-desulfurization method still having comparative advantage at present, and its advantage is that cost of equipment is low, flexible operation, and the winding-up time is short, and hot metal temperature drop is little; Maximum shortcoming is that dynamic conditions is poor.
The patent of invention that the patent No. is 201110222088 provides the method for the pre-desulfurization of a kind of bottom blowing powder injection.The method is that in the molten bath that the mixture of calcium carbide powder and basic metal material is jetted sweetening agent in hot metal ladle by the dusting device of hot metal ladle bottom, its advantage is that cost is low, simple to operate.
For top-blown powder sulfur removal technology, the passivated magnesium that is blown into molten iron gasifies rapidly, in spray gun exit or dissolve in rapidly molten iron, or with the form floating of small bubbles, and in the process of floating, continue to dissolve in molten iron or directly contact generation desulphurization reaction with the sulphur in molten iron.Data shows, magnesium steam bubble can only slough 3%~8% by the sulphur in molten iron, so the magnesium that desulphurization reaction or take dissolves is as main.Accelerate magnesium bubble to the speed of dissolving in molten iron, the solubleness that improves magnesium in molten iron is most important to improving the utilization ratio of magnesium.
While adopting conventional top-blown powder desulfurization operations, owing to existing larger dead band, desulfurization powder to be difficult to move to hot metal ladle bottom in hot metal ladle, pulvis utilization ratio is low.Meanwhile, merely utilize raising top blast load volume to add strong mixing, and then quickening magnesium is inappropriate to the dissolving in molten iron.Along with the raising of top blast load volume, its impact that bath is all done time is less, and meanwhile, load volume is larger, and the magnesium steam that carrier gas is swept along is away more, causes the utilization ratio of magnesium powder to reduce.
Because the dynamic conditions of top-blown powder doctor treatment is poor, the utilization ratio of magnesium is always lower, causes desulfurization processing efficiency low, and to cost efficiency, work has brought disadvantageous effect.
Summary of the invention
For the problem of existing top blast molten iron pretreatment desulfurizing existence, the invention provides the apparatus and method for of top and bottom complex blowing desulfurizing iron in a kind of hot metal ladle.
Method of the present invention is:
1, equipment aspect
As shown in Figures 1 and 2, the equipment of this invention is mainly by top-blown powder tank (1), bottom blowing powder injection tank (2), hot metal ladle (3), top-blown spray gun (4), bottom blowing ventilated element (5) forms, wherein between the rifle body of top-blown spray gun (4) and hot metal ladle (3) central axis, maintain certain angle α, these angle α=10~20 °, one end of top-blown spray gun (4) is connected with top-blown powder tank (1), the degree of depth that the other end of top-blown spray gun (4) inserts molten iron is about 200~300mm apart from hot metal ladle bottom surface, the muzzle of top-blown spray gun (4) is centered close on hot metal ladle (3) central axis, the rifle body medullary ray of top-blown spray gun (4) and bottom blowing ventilated element (5) medullary ray are all in the same vertical elevation through hot metal ladle (3) bottom surface diameter, bottom blowing powder injection tank (2) is connected with bottom blowing ventilated element (5), bottom blowing ventilated element (5) is centered close to 1/2nd places of hot metal ladle (3) bottom surface radius.
2, process aspect
Use aforesaid device to smelt, wherein:
(1) top blast: top-blown spray gun (4) be take nitrogen as carrier, at the about about ton iron 0.05~0.08Nm of 0.18~0.22MPa, nitrogen flow of jetting pressure 3under the condition of/min, with the about winding-up intensity of ton iron 0.00~0.08kg/min, the magnesium powder in top-blown powder tank (1) is jetted in molten steel, magnesium powder after gasification is promptly taken away by bottom blown gas and is incorporated in iron liquid, approximately 0~0.5kg/t molten iron is measured in the winding-up of magnesium powder, the winding-up time is 0~6min approximately, and powder to air ratio is about 1.0kg/Nm 3.
(2) bottom blowing: nitrogen buffer gas is jetted the desulfurization powder in bottom blowing powder injection tank to hot metal ladle (3) by bottom blowing ventilated element (5), jetting pressure is the about ton iron 0.05~0.1Nm of 0.3~0.5MPa, nitrogen flow approximately 3/ min, winding-up intensity is ton iron 0~0.4kg/min approximately, and approximately 0~4kg/t molten iron is measured in the winding-up of desulfurization powder, and the winding-up time is 8~10min, and powder to air ratio is about 3kg/Nm 3.Top and bottom complex blowing can form comparatively strong stirring, drives molten iron Rapid Circulation, thereby has greatly improved the dynamic conditions of desulfurization.
According to starting condition such as the initial sulphur content of molten iron, molten iron temperatures, determine the proper ratio of different desulfurization stage bottom blowing pulvis and top blast magnesium powder, while wherein requiring final sulfur content higher than 100ppm, adopt mass ratio 1: 0~0.3; When sulphur content blowing magnesium powder during lower than 100ppm, early stage, the mixture to hot metal ladle (3) interior spray calcium carbide powder and calcium oxide came desulfurizing iron by bottom blowing ventilated element (5), molten steel sulfur content reaches 0.010% and enters the later stage, and now blowing magnesium powder carries out dark desulfurization to molten iron.
Bottom blowing ventilated element of the present invention (5) is selected the disclosed a kind of gas permeable brick for end powder injection process of the Chinese patent application of ZL2005201458206.Utilize this gas permeable brick to do bottom blowing ventilated element (5), can not take bottom blowing powder injection operation, only by bottom blowing, strengthen the stirring in molten bath, improve the dissolution rate of magnesium in molten bath, improve the utilization ratio of magnesium; Also can be blown into the mixture of calcium carbide powder and calcium oxide, further reduce the consumption of magnesium powder.
Adopt two powder spraying pots, because bottom blowing is subject to the impact of ferrostatic pressure and bottom blowing element, its jetting pressure is higher than top blast, simultaneously because bottom blown gas is to be directly blown into from hot metal ladle (3) bottom blowing ventilated element (5), can make full use of the power merit of bubble, thereby in the situation that not increasing gas gross, improve the stirring capacity of bath.
Experimental result shows, under equal carrier gas flux, all doing time and shortened 15~20% of the more single Top Blown Process of top and bottom complex blowing technique, saves magnesium powder 0.20~0.30kg/t molten iron.
Accompanying drawing explanation
Accompanying drawing 1 is testing apparatus schematic diagram;
Accompanying drawing 2 is top-blown spray gun (4), Bottom Blowing Ejection Gun and hot metal ladle (3) position view.
In accompanying drawing, 1 is top-blown powder tank (dress magnesium powder); 2 is bottom blowing powder injection tank (dress calcium carbide and calcium oxide mixing powder); 3 is hot metal ladle; 4 is top-blown spray gun; 5 is bottom blowing ventilated element.
Embodiment
Below in conjunction with specific embodiment, further describe the present invention, the present invention utilizes conventional spray gun to carry out top spray to blow, and utilizes the slit gas permeable brick that dusts to carry out end winding-up, in these two kinds of modes, is combined with each other and carries out desulfurization processing.Specifically be implemented as follows:
Embodiment 1:
The present invention implements at the scene, and for desulfurizing iron, the temperature of processed molten iron is 1390 ℃, and the initial sulphur content of molten iron is 0.035%.
The angle of top-blown spray gun during enforcement (4) rifle body and hot metal ladle (3) central axis is 18 °, the degree of depth that top-blown spray gun (4) inserts molten iron is apart from the bag about 220mm in the end, being centered close on hot metal ladle (3) central axis of muzzle, body of spray gun rifle medullary ray and bottom blowing ventilated element (5) medullary ray are in together in the same vertical elevation through hot metal ladle (3) bottom surface diameter, bottom blowing ventilated element (5) is centered close to 1/2nd places of hot metal ladle (3) bottom surface radius, what the set bottom blowing ventilated element (5) in hot metal ladle (3) bottom was used is bottom ventilated element, gas permeable brick specification is Φ 74 * Φ 104 * 160mm.
Jet early stage: top-blown spray gun (4) nitrogen-blow, jetting pressure is 0.20MPa, nitrogen flow is a ton iron 0.06Nm 3/ min; The bottom blowing nitrogen flow short period of time is interior by 0.05Nm 3/ min is increased to 0.1Nm 3during/min, the main component that starts to jet is the passive lime of CaO, and jetting pressure is 0.4MPa, and winding-up intensity is ton molten iron 0.28kg/min, and the time of dusting is 9 minutes, records molten steel sulfur content and has been reduced to 0.010%.
The winding-up later stage: a bottom ventilated element nitrogen-blow, jetting pressure is 0.4MPa, nitrogen flow is ton iron 0.1Nm 3/ min; Top-blown spray gun (4) be take nitrogen and is blown into magnesium powder as carrier, jetting pressure 0.20MPa, and carrier gas flux is a ton iron 0.06Nm 3/ min, winding-up intensity is ton molten iron 0.05kg/min, and the spray magnesium time is 3.5 minutes, and the molten steel sulfur content after processing is 0.002%, saves magnesium powder 0.28kg/t molten iron.

Claims (2)

1. the method for a pre-desulfuration of molten iron in foundry ladle, it is characterized in that the equipment using in method is mainly by top-blown powder tank, bottom blowing powder injection tank, hot metal ladle, top-blown spray gun, bottom blowing ventilated element forms, angle α=10~20 ° that wherein keep between the rifle body of top-blown spray gun and hot metal ladle central axis, one end of top-blown spray gun is connected with top-blown powder tank, the other end of top-blown spray gun inserts the degree of depth of molten iron apart from hot metal ladle bottom surface 200~300mm, the muzzle of top-blown spray gun is centered close on hot metal ladle central axis, the rifle body medullary ray of top-blown spray gun and bottom blowing ventilated element medullary ray are all in the same vertical elevation through hot metal ladle bottom surface diameter, bottom blowing powder injection tank and bottom blowing ventilated element together with, bottom blowing ventilated element is centered close to 1/2nd places of hot metal ladle bottom surface radius,
While using aforesaid device to carry out molten iron pre-desulfurization, take following method:
(1) top-blown spray gun be take nitrogen as carrier, at jetting pressure, is that 0.18~0.22MPa, nitrogen flow are ton iron 0.05~0.08Nm 3under the condition of/min, with the winding-up intensity of ton iron 0.00~0.08kg/min, the magnesium powder in top-blown powder tank is jetted in molten steel, magnesium powder winding-up amount is 0~0.5kg/t molten iron, winding-up time 0~6min, and powder to air ratio is about 1.0kg/Nm 3;
(2) bottom blowing nitrogen buffer gas is jetted desulfurization powder in bottom blowing powder injection tank to hot metal ladle by bottom blowing ventilated element, and jetting pressure 0.3~0.5MPa, nitrogen flow are ton iron 0.05~0.1Nm 3/ min, winding-up intensity is ton iron 0~0.4kg/min, and the winding-up amount of desulfurization powder is 0~4kg/t molten iron, and the winding-up time is 8~10min, and powder to air ratio is about 3kg/Nm 3.
2. method according to claim 1, it is characterized in that in described method according to starting condition such as the initial sulphur content of molten iron, molten iron temperatures, determine the proper ratio of different desulfurization stage bottom blowing pulvis and top blast magnesium powder, while wherein requiring final sulfur content higher than 100ppm, adopting mass ratio is 1: 0~0.3; When sulphur content blowing magnesium powder during lower than 100ppm.
CN201410118031.7A 2014-03-27 2014-03-27 A kind of method of top and bottom complex blowing molten iron pre-desulfurization in hot metal ladle Expired - Fee Related CN103924025B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410118031.7A CN103924025B (en) 2014-03-27 2014-03-27 A kind of method of top and bottom complex blowing molten iron pre-desulfurization in hot metal ladle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410118031.7A CN103924025B (en) 2014-03-27 2014-03-27 A kind of method of top and bottom complex blowing molten iron pre-desulfurization in hot metal ladle

Publications (2)

Publication Number Publication Date
CN103924025A true CN103924025A (en) 2014-07-16
CN103924025B CN103924025B (en) 2015-09-30

Family

ID=51142415

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410118031.7A Expired - Fee Related CN103924025B (en) 2014-03-27 2014-03-27 A kind of method of top and bottom complex blowing molten iron pre-desulfurization in hot metal ladle

Country Status (1)

Country Link
CN (1) CN103924025B (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104480251A (en) * 2014-12-05 2015-04-01 中冶京诚工程技术有限公司 Pretreatment device for simultaneously desulfurizing, desiliconizing and dephosphorizing molten iron, and application and smelting method thereof
CN106755738A (en) * 2015-11-24 2017-05-31 上海梅山钢铁股份有限公司 A kind of method for improving molten iron pretreatment desulfurizing pulvis deactivating magnesium powder utilization rate
CN107513598A (en) * 2017-07-20 2017-12-26 首钢集团有限公司 A kind of molten iron tank deck bottom composite blowing sulfur method
CN107663560A (en) * 2016-07-28 2018-02-06 上海梅山钢铁股份有限公司 The control method of pulverized limestone dosage in a kind of magnesium-based composite blowing Desulphuring Process of Molten Iron
CN109072320A (en) * 2016-04-25 2018-12-21 新日铁住金株式会社 The sulfur method and desulfurizer of molten iron
CN110157854A (en) * 2019-06-04 2019-08-23 甘肃酒钢集团宏兴钢铁股份有限公司 A method of the deoxidation of molten steel alloying in converter
CN113502367A (en) * 2021-07-09 2021-10-15 吕梁建龙实业有限公司 Molten iron desulphurization pretreatment process and method
CN115287404A (en) * 2022-07-29 2022-11-04 鞍钢股份有限公司 Pretreatment method of molten iron in converter

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0790337A (en) * 1993-07-27 1995-04-04 Kawasaki Steel Corp Pretreatment method for simultaneous dephosphorization and desulphurization of hot metal
JPH0813016A (en) * 1994-07-01 1996-01-16 Kawasaki Steel Corp Method for dephosphorizing and desulfurizing molten iron
JPH0892618A (en) * 1994-09-22 1996-04-09 Kobe Steel Ltd Prerefining method
CN1461812A (en) * 2002-05-31 2003-12-17 李江 Method and device for pretreating metal iron using torpedo hot metal mixer car diversified composite jetting method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0790337A (en) * 1993-07-27 1995-04-04 Kawasaki Steel Corp Pretreatment method for simultaneous dephosphorization and desulphurization of hot metal
JPH0813016A (en) * 1994-07-01 1996-01-16 Kawasaki Steel Corp Method for dephosphorizing and desulfurizing molten iron
JPH0892618A (en) * 1994-09-22 1996-04-09 Kobe Steel Ltd Prerefining method
CN1461812A (en) * 2002-05-31 2003-12-17 李江 Method and device for pretreating metal iron using torpedo hot metal mixer car diversified composite jetting method

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104480251A (en) * 2014-12-05 2015-04-01 中冶京诚工程技术有限公司 Pretreatment device for simultaneously desulfurizing, desiliconizing and dephosphorizing molten iron, and application and smelting method thereof
CN106755738A (en) * 2015-11-24 2017-05-31 上海梅山钢铁股份有限公司 A kind of method for improving molten iron pretreatment desulfurizing pulvis deactivating magnesium powder utilization rate
CN109072320A (en) * 2016-04-25 2018-12-21 新日铁住金株式会社 The sulfur method and desulfurizer of molten iron
CN107663560A (en) * 2016-07-28 2018-02-06 上海梅山钢铁股份有限公司 The control method of pulverized limestone dosage in a kind of magnesium-based composite blowing Desulphuring Process of Molten Iron
CN107663560B (en) * 2016-07-28 2019-09-17 上海梅山钢铁股份有限公司 The control method of pulverized limestone dosage in a kind of magnesium-based composite blowing Desulphuring Process of Molten Iron
CN107513598A (en) * 2017-07-20 2017-12-26 首钢集团有限公司 A kind of molten iron tank deck bottom composite blowing sulfur method
CN110157854A (en) * 2019-06-04 2019-08-23 甘肃酒钢集团宏兴钢铁股份有限公司 A method of the deoxidation of molten steel alloying in converter
CN113502367A (en) * 2021-07-09 2021-10-15 吕梁建龙实业有限公司 Molten iron desulphurization pretreatment process and method
CN115287404A (en) * 2022-07-29 2022-11-04 鞍钢股份有限公司 Pretreatment method of molten iron in converter
CN115287404B (en) * 2022-07-29 2023-11-10 鞍钢股份有限公司 Converter molten iron pretreatment method

Also Published As

Publication number Publication date
CN103924025B (en) 2015-09-30

Similar Documents

Publication Publication Date Title
CN103924025B (en) A kind of method of top and bottom complex blowing molten iron pre-desulfurization in hot metal ladle
CN107513598B (en) A kind of molten iron tank deck bottom composite blowing sulfur method
CN109207672A (en) A kind of production method of Slagoff method and ultra-low phosphoretic steel in ultra-low phosphoretic steel production process
CN106755738A (en) A kind of method for improving molten iron pretreatment desulfurizing pulvis deactivating magnesium powder utilization rate
JP2016151027A (en) Production method of molten steel
JPS6023163B2 (en) steel smelting method
JP2019119906A (en) Converter refining method
CN109790590B (en) Dephosphorization apparatus and dephosphorization method of molten iron using the same
JPS5828324B2 (en) Youtetsuno Datsuryuuzai
CN103757179A (en) Method for deeply desulfurizing semisteel
CN102268505A (en) Method for pre-desulfuration of molten iron in foundry ladle
CN103773918A (en) Method for reducing resulfurization of semisteel-making converter
TWI703219B (en) Dephosphorization method of hot metal
KR20040053602A (en) Desulfurization material injecting method for improving desulfurizing efficiency
JP2018035376A (en) Hot metal dephosphorization method
JP5962616B2 (en) Hot metal pretreatment method
CN106244760B (en) A kind of method of vanadium-bearing hot metal dephosphorization in converter extracting vanadium
CN216891064U (en) KR desulfurization equipment for molten iron pretreatment
CN113122673A (en) CaC using calcium carbide2Process for pretreating converter blowing end point steel slag
CN105734194A (en) Molten iron pre-desilication process for converter steelmaking
JP2005089839A (en) Method for refining molten steel
CN103320570A (en) Method for manufacturing steel
JP2019090078A (en) Immersion lance for blowing and refining method of molten iron
CN103320574A (en) Molten iron dephosphorizing method
CN109468433A (en) Fluxing agent and the molten iron method of refining for utilizing it

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20150930

Termination date: 20160327

CF01 Termination of patent right due to non-payment of annual fee