CN104611513A - Method for utilizing vanadium in steel slag - Google Patents

Method for utilizing vanadium in steel slag Download PDF

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Publication number
CN104611513A
CN104611513A CN201510054126.1A CN201510054126A CN104611513A CN 104611513 A CN104611513 A CN 104611513A CN 201510054126 A CN201510054126 A CN 201510054126A CN 104611513 A CN104611513 A CN 104611513A
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steel
slag
vanadium
reductive agent
heating
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CN104611513B (en
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魏跃军
张俊粉
李凤臣
王琪
陈超
高玲玲
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Chengde Branch of HBIS Co Ltd
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Hebei Iron and Steel Group Co Ltd Chengde Branch
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Treatment Of Steel In Its Molten State (AREA)
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Abstract

The invention relates to a method for utilizing vanadium in steel slag, and belongs to the technical field of metallurgy. The specific process is as follows: conveying steel slag of generated by steel discharge of a converter into a refining LF furnace, adding lime and fluorite, and adding a reducing agent to reduce vanadium oxide in the slag; meanwhile, using an LF furnace electrode to supplement heat, and adjusting argon flow to increase the interfacial reaction of the steel slag after heating, to promote the reduction reaction. During steel discharge of the converter, the discharge quantity of the steel slag is increased, the refining LF furnace is used for reducing the vanadium oxide in the steel slag, the vanadium oxide in the steel slag is reduced to be lower than 0.03%, the vanadium recovery rate in molten steel is 0.008-0.015%, the recycled phosphor is not larger than 0.003%, vanadium is used for alloying steel to achieve the purpose of resource recovery, the requirements of a smelting process can be satisfied, and an obvious effect is achieved.

Description

The Application way of vanadium in a kind of slag
Technical field
The invention belongs to metallurgical technology field, particularly relate to the Application way of vanadium in a kind of slag.
Background technology
Chengde area vanadium titano-magnetite rich reserves, for world-class vanadium titano-magnetite base, current China and most countries many employings indirect method vanadium extraction in the world, namely after first molten iron being smelt in ore deposit, recycling converter is oxidized the raw material of slag as vanadium extraction that blowing obtains containing vanadium, semi-steel after extraction of vanadium (molten iron namely after vanadium extraction) is still containing higher residual vanadium, in addition the restriction of indivedual operation processing power in vanadium-bearing hot metal technical process, part vanadium-bearing hot metal is directly blended into steel-making converter without vanadium extraction, the residual vanadium oxidation having a great deal of in this process half steel or molten iron enters slag, make the V in slag 2o 5content is higher, is generally 3 ~ 5%.
V-bearing steel slag is high alkalinity, low-grade furnace charge, and main component is CaO 40 ~ 60%, TFe 11 ~ 12%, Si0 27 ~ 10%, MgO 5 ~ 11%, V 2o 53 ~ 5%.V-bearing steel slag is metallurgical secondary resource that is important, that have very much utility value, can be used as and extracts V 2o 5important source material, but due to its calcium, iron level high, content of vanadium is low, vanadium existence is complicated, Dispersed precipitate in multi mineral mutually in, make vanadium wherein be difficult to recycle, current vanadium in vanadium containing steel slag cannot realize resource reutilization, and many air storages, cause disadvantageous effect to environment.
Summary of the invention
Technical problem to be solved by this invention is: V in slag 2o 5recycling, go out the quantity of slag mainly through increasing slag in converter tapping process, refining utilizes the V in aluminium powder, silicon carbide, ferrosilicon powder reduced steel slag 2o 5enter molten steel, realize vanadium resource recycling.
For solving the problems of the technologies described above, in a kind of slag of the present invention, the Application way of vanadium takes following processing step: after the slag of converter tapping enters refining LF stove, add lime, fluorite, adds the vanadium oxide in reductive agent reducing slag; Utilize the concurrent heating of LF stove electrode, after heating, adjustment argon flow amount increases slag interface reaction, promotes reduction reaction simultaneously.
Reductive agent of the present invention is any one or a few in ferrosilicon powder, silicon carbide, aluminium powder; Reductive agent addition is ferrosilicon powder 0.5-1.0kg/t steel, silicon carbide 0.5-1.0kg/t steel, aluminium powder 0.5-1.0kg/t steel.
During converter tapping of the present invention, thickness of steel slag is 200-500mm.
Of the present invention enter refining LF stove after add lime 3-6kg/t steel, fluorite 1-2kg/t steel, makes CaO/SiO in slag 2for 5-8, reductive agent add-on 0.5-3.0kg/t steel.
Of the present inventionly should utilize the concurrent heating of LF stove heated by electrodes, Heating temperature is 1590-1620 DEG C, and heat-up time is 10-15min.
Argon flow amount 1000-1500nL/min is adjusted, time 3-5min after heating of the present invention.
Slag amount 350mm of the present invention, adds lime 4kg/t steel, fluorite 1.2kg/t steel, and add reductive agent 1.8kg/t steel, reductive agent is ferrosilicon powder 0.5kg/t steel, silicon carbide 0.5kg/t steel, aluminium powder 0.8kg/t steel; CaO/SiO in slag 2be 5, electrode concurrent heating 12min, temperature is 1590 DEG C, argon flow amount 1200nL/min, time 3min after heating.
Slag amount 400mm of the present invention, adds lime 4.5kg/t steel, fluorite 1.5kg/t steel, and add reductive agent 1.7kg/t steel, reductive agent is silicon carbide 0.8kg/t steel, aluminium powder 0.9kg/t steel; CaO/SiO in slag 2be 6, electrode concurrent heating 13min, temperature is 1620 DEG C, argon flow amount 1300nL/min, time 5min after heating.
Slag amount 450mm of the present invention, adds lime 5.0kg/t steel, fluorite 1.8kg/t steel, and add reductive agent 1.8kg/t steel, reductive agent is silicon carbide 0.9kg/t steel, aluminium powder 0.9kg/t steel; CaO/SiO in slag 2be 8, electrode concurrent heating 13min, temperature is 1600 DEG C, argon flow amount 1200nL/min, time 4min after heating.
theoretical basis of the present invention
Thermodynamics: utilize Basic thermodynamics data can derive barium oxide and changed by the standard Gibbs free energy that C, Si, Al reduce.
V 2O 5（s）+C （s）=2 VO 2（s）+CO （g）△G 0=-49070-213.42T (1)
VO 2（s）+1/2C （s）=1/2 V2O 3（s）+1/2CO （g）△G 0=47650.25-79.433T (2)
V 2O 3（s）+C （s）=2VO （s）+CO （g）△G 0=239099.5-163.215T (3)
VO （s）+C （s）=V （s）+CO （g）△G 0=310300-165.81T (4)
Because V and carbon have larger avidity, the red-hot vanadium metal generated in reaction can react with carbon immediately and generate VC, V 2c.The standard Gibbs free energy change of this reaction is shown in for (5), (6) formula.
V （s）+C （s）=VC （s） △G 0=-102100+9.58T (5)
2V （s）+C （s）=V 2C （s） △G 0=-146400+3.35T (6)
At relatively high temperatures, the standard Gibbs free energy change of more than reacting be all negative, can occur viewed from thermodynamics, but the heat that reaction (5), (6) need absorption a large amount of, therefore react and carry out under refining LF stove heating condition, be conducive to above-mentioned reaction and occur.
V 2O 5（s）+5/2Si （s）=2V （s）+5/2SiO 2（s）△G 0=-747710+47.855T (7)
VO 2（s）+Si （s）=V （s）+SiO 2（s）△G 0=-198460+18.07T (8)
V 2O 3（s）+3/2Si （s）=2V （s）+3/2SiO 2（s）△G 0=-154240+22.545T (9)
VO （s）+1/2Si （s）=V （s）+1/2SiO 2（s）△G 0=-27680+6.65T (10)
V 2O 5（s）+10/3Al （s）=2V （s）+5/3 Al 5O 3（s）△G 0=-1280000+132.1T (11)
VO 2（s）+4/3Al （s）=V （s）+2/3Al 5O 3（s）△G 0=-410433+18.07T (12)
V 2O 3（s）+2Al （s）=2V （s）+Al 5O 3（s）△G 0=-472200+75.67T (13)
3VO （s）+2Al （s）=3V （s）+Al 5O 3（s）△G 0=-401000+149.78T (14)
Above-mentioned reaction normal gibbs free energy changeization is all negative, can occur viewed from thermodynamics.According to the experience of metal-thermic smelting ferrovanadium alloy, after the reaction heat of above-mentioned reaction reaches certain value, reaction can spontaneously be carried out, and exothermic heat of reaction can reach and makes load melting, reaction and can reach the degree making slag sluicing system.During oxide compound with Si reduction vanadium, due to shortage of heat, reaction is carried out slowly and not exclusively, must external heat source, such as electric energy.During oxide compound with aluminium reducing vanadium, the heat release of self just can maintain the carrying out of reaction.And have a surplus due to thermite reaction thermal value, also need add inert material in furnace charge, to reduce furnace charge thermal value, ensure that reacting balance carries out.Thermite reaction carries out speed soon simultaneously, and the reaction times is short, is difficult to control.In actual smelting, do just reduction with ferrosilicon, make whole reductive agent with aluminium.
The beneficial effect adopting technique scheme to produce is: increase the tapping quantity of slag during present method converter tapping, utilize the oxide compound of vanadium in refining LF stove reduced steel slag, in slag, the oxide compound of vanadium is reduced to less than 0.03%, molten steel reclaims vanadium 0.008% ~ 0.015%, rephosphorization≤0.003%, utilizes vanadium to carry out alloying to steel, reaches the object of resource reutilization, smelting technology needs can be met, achieve obvious effect.
Embodiment
Below in conjunction with embodiment, the present invention is further detailed explanation.
Embodiment 1
Smelt SS400 converter tapping slag thickness 350mm, after entering refining LF stove, add lime 4kg/t steel, fluorite 1.2kg/t steel, add reductive agent 1.8kg/t steel, reductive agent is ferrosilicon powder 0.5kg/t steel, silicon carbide 0.5kg/t steel, aluminium powder 0.8kg/t steel; CaO/SiO in slag 2be 5, reduce rephosphorization, utilize LF stove electrode concurrent heating 12min, temperature is 1590 DEG C simultaneously, and after heating, adjustment argon flow amount 1200nL/min, time 3min, increase slag interface reaction, promote reduction reaction.The oxide compound that reaction terminates vanadium in rear detection slag is 0.029%, and molten steel vanadium is 0.010%, rephosphorization 0.002%.
Embodiment 2
Smelt SS400 converter tapping slag thickness 400mm, after entering refining LF stove, add lime 4.5kg/t steel, fluorite 1.5kg/t steel, add reductive agent 1.7kg/t steel, reductive agent is silicon carbide 0.8kg/t steel, aluminium powder 0.9kg/t steel; CaO/SiO in slag 2be 6, reduce rephosphorization, utilize LF stove electrode concurrent heating 13min, temperature is 1620 DEG C simultaneously, and after heating, adjustment argon flow amount 1300nL/min, time 5min, increase slag interface reaction, promote reduction reaction.The oxide compound that reaction terminates vanadium in rear detection slag is 0.027%, and molten steel vanadium is 0.012%, rephosphorization 0.003%.
Embodiment 3
Smelt SS400 converter tapping slag thickness 450mm, after entering refining LF stove, add lime 5.0kg/t steel, fluorite 1.8kg/t steel, add reductive agent 1.8kg/t steel, reductive agent is silicon carbide 0.9kg/t steel, aluminium powder 0.9kg/t steel; CaO/SiO in slag 2be 8, reduce rephosphorization, utilize LF stove electrode concurrent heating 13min, temperature is simultaneously--1600 DEG C, after heating, adjustment argon flow amount 1200nL/min, time 4min, increase slag interface reaction, promote reduction reaction.The oxide compound that reaction terminates vanadium in rear detection slag is 0.028%, and molten steel vanadium is 0.014%, rephosphorization 0.003%.
Embodiment 4
Smelt SS400 converter tapping slag thickness 200mm, after entering refining LF stove, add lime 3.0kg/t steel, fluorite 1.0kg/t steel, add reductive agent ferrosilicon powder 1kg/t steel; CaO/SiO in slag 2be 7, reduce rephosphorization, utilize LF stove electrode concurrent heating 10min, temperature is 1595 DEG C simultaneously, and after heating, adjustment argon flow amount 1000nL/min, time 3min, increase slag interface reaction, promote reduction reaction.The oxide compound that reaction terminates vanadium in rear detection slag is 0.026%, and molten steel vanadium is 0.013%, rephosphorization 0.003%.
Embodiment 5
Smelt SS400 converter tapping slag thickness 550mm, after entering refining LF stove, add lime 6.0kg/t steel, fluorite 2.0kg/t steel, add reductive agent 3kg/t steel, reductive agent is ferrosilicon powder 1kg/t steel, silicon carbide 1kg/t steel, aluminium powder 1kg/t steel; CaO/SiO in slag 2be 8, reduce rephosphorization, utilize LF stove electrode concurrent heating 15min, temperature is simultaneously--1615 DEG C, after heating, adjustment argon flow amount 1500nL/min, time 5min, increase slag interface reaction, promote reduction reaction.The oxide compound that reaction terminates vanadium in rear detection slag is 0.024%, and molten steel vanadium is 0.015%, rephosphorization 0.002%.

Claims (9)

1. the Application way of vanadium in slag, is characterized in that, after the slag of converter tapping enters refining LF stove, adds lime, fluorite, adds the vanadium oxide in reductive agent reducing slag; Utilize the concurrent heating of LF stove electrode, after heating, adjustment argon flow amount increases slag interface reaction, promotes reduction reaction simultaneously.
2. the Application way of vanadium in a kind of slag according to claim 1, is characterized in that, described reductive agent is any one or a few in ferrosilicon powder, silicon carbide, aluminium powder; Reductive agent addition is ferrosilicon powder 0.5-1.0kg/t steel, silicon carbide 0.5-1.0kg/t steel, aluminium powder 0.5-1.0kg/t steel.
3. the Application way of vanadium in a kind of slag according to claim 1, it is characterized in that, during converter tapping, thickness of steel slag is 200-500mm.
4. the Application way of vanadium in a kind of slag according to claim 1, is characterized in that, described in enter refining LF stove after add lime 3-6kg/t steel, fluorite 1-2kg/t steel, makes CaO/SiO in slag 2for 5-8, reductive agent add-on 0.5-3.0kg/t steel.
5. the Application way of vanadium in a kind of slag according to claim 1, is characterized in that, describedly should utilize the concurrent heating of LF stove heated by electrodes, and Heating temperature is 1590-1620 DEG C, and heat-up time is 10-15min.
6. the Application way of vanadium in a kind of slag according to claim 1, is characterized in that, adjust argon flow amount 1000-1500nL/min after described heating, time 3-5min.
7. the Application way of vanadium in a kind of slag according to claim 1-6 any one, it is characterized in that, described slag amount 350mm, add lime 4kg/t steel, fluorite 1.2kg/t steel, add reductive agent 1.8kg/t steel, reductive agent is ferrosilicon powder 0.5kg/t steel, silicon carbide 0.5kg/t steel, aluminium powder 0.8kg/t steel; CaO/SiO in slag 2be 5, electrode concurrent heating 12min, temperature is 1590 DEG C, argon flow amount 1200nL/min, time 3min after heating.
8. in a kind of slag according to claim 1-6 any one, the Application way of vanadium, is characterized in that, described slag amount 400mm, add lime 4.5kg/t steel, fluorite 1.5kg/t steel, add reductive agent 1.7kg/t steel, reductive agent is silicon carbide 0.8kg/t steel, aluminium powder 0.9kg/t steel; CaO/SiO in slag 2be 6, electrode concurrent heating 13min, temperature is 1620 DEG C, argon flow amount 1300nL/min, time 5min after heating.
9. in a kind of slag according to claim 1-6 any one, the Application way of vanadium, is characterized in that, described slag amount 450mm, add lime 5.0kg/t steel, fluorite 1.8kg/t steel, add reductive agent 1.8kg/t steel, reductive agent is silicon carbide 0.9kg/t steel, aluminium powder 0.9kg/t steel; CaO/SiO in slag 2be 8, electrode concurrent heating 13min, temperature is 1600 DEG C, argon flow amount 1200nL/min, time 4min after heating.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106811576A (en) * 2015-12-02 2017-06-09 鞍钢股份有限公司 Converter slag thermal state recycling method
CN109295316A (en) * 2018-12-05 2019-02-01 盐边县向阳钒业有限公司 The recovery process of vanadium in vanadium containing steel slag
CN109457117A (en) * 2018-11-16 2019-03-12 河北工程大学 A kind of method of valuable constituent element comprehensive reutilization in steel slag
CN111057877A (en) * 2019-12-31 2020-04-24 永平县勇泰工业废渣有限公司 Ingredient for refining vanadium from low-grade vanadium waste residue
CN112063803A (en) * 2020-08-05 2020-12-11 新兴铸管股份有限公司 Method for reducing vanadium element in slag of refining furnace

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JP2002235123A (en) * 2001-02-02 2002-08-23 Nippon Cms Kk Method for recovering valuable metal from used catalyst
CN101067182A (en) * 2007-06-05 2007-11-07 钢铁研究总院 V2O5 direct alloying steelmaking technology
CN101798618A (en) * 2010-03-26 2010-08-11 河北钢铁股份有限公司承德分公司 Method for performing vanadium increase and refining in vanadium alloying by utilizing vanadium slag
CN103131852A (en) * 2013-03-06 2013-06-05 河北钢铁股份有限公司承德分公司 Method for utilizing sludge containing vanadium and chromium

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1071708A (en) * 1991-10-17 1993-05-05 承德钢铁厂 Directly alloying process in vanadium slag furnace
JP2002235123A (en) * 2001-02-02 2002-08-23 Nippon Cms Kk Method for recovering valuable metal from used catalyst
CN101067182A (en) * 2007-06-05 2007-11-07 钢铁研究总院 V2O5 direct alloying steelmaking technology
CN101798618A (en) * 2010-03-26 2010-08-11 河北钢铁股份有限公司承德分公司 Method for performing vanadium increase and refining in vanadium alloying by utilizing vanadium slag
CN103131852A (en) * 2013-03-06 2013-06-05 河北钢铁股份有限公司承德分公司 Method for utilizing sludge containing vanadium and chromium

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106811576A (en) * 2015-12-02 2017-06-09 鞍钢股份有限公司 Converter slag thermal state recycling method
CN106811576B (en) * 2015-12-02 2019-01-04 鞍钢股份有限公司 Converter slag thermal state recycling method
CN109457117A (en) * 2018-11-16 2019-03-12 河北工程大学 A kind of method of valuable constituent element comprehensive reutilization in steel slag
CN109295316A (en) * 2018-12-05 2019-02-01 盐边县向阳钒业有限公司 The recovery process of vanadium in vanadium containing steel slag
CN111057877A (en) * 2019-12-31 2020-04-24 永平县勇泰工业废渣有限公司 Ingredient for refining vanadium from low-grade vanadium waste residue
CN112063803A (en) * 2020-08-05 2020-12-11 新兴铸管股份有限公司 Method for reducing vanadium element in slag of refining furnace

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