CN1243882A - Low-basicity less-slag iron smelting technology for blast furnace with external desulfurizing greatly of molten iron - Google Patents
Low-basicity less-slag iron smelting technology for blast furnace with external desulfurizing greatly of molten iron Download PDFInfo
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- CN1243882A CN1243882A CN 98121520 CN98121520A CN1243882A CN 1243882 A CN1243882 A CN 1243882A CN 98121520 CN98121520 CN 98121520 CN 98121520 A CN98121520 A CN 98121520A CN 1243882 A CN1243882 A CN 1243882A
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Abstract
A technology for smelting iron with blast furnace features that the sulfur in molten iron is greatly removed outside the furnace with low cost, so lowering desulfurizing cost and realizing low-basicity less-slag smelting of blast furnace. Said desulfurizing agent is ordinary lime-series one. In addition, raw magnesium is added to molten iron runner. With the better dynamic condition of molten iron in tapping and tranportation procedure, the sulfur in molten ion can be reduced to zero. Its advantages are less investment and quickly taking its effect.
Description
The present invention relates to the ironmaking novel process of sulfur removal technology in the blast furnace ironmaking process and even whole slagging regime, burden structure.
Slagging regime requires slag in the blast furnace ironmaking process: 1. alap temperature of fusion and melting temperature and less viscosity are arranged not increasing under the direct reductive situations of element such as Fe, Mn, Si; 2. to have the ability ((S)≤0.03%) that higher basicity guarantees enough to remove sulphur in the molten iron (S).Sometimes also to add certain MgO,, adapt to the fluctuation of furnace temperature and charge composition in order to improve the thermostability and the chemical stability of slag.Smelting low-grade iron ore, contain SiO in the gangue like this
2Higher, former, fuel contains Al
2O
3When higher, the ironmaking of high basicity certainly will cause slag iron than raising, and sometimes even up to 600～900kg/TP and even more than one ton, so just makes blast furnace ironmaking production efficiency low unavoidably, and the fuel consumption height is low in economic efficiency.
Purpose of the present invention is exactly a kind of ironmaking novel process that proposes at the problems referred to above.In the existing iron-smelting process various secondary desulfurization method is arranged, but all carry out for alleviating next step steel making working procedure desulfurization task.Have is that the desulfurization of only the extra molten iron that occurs occasionally being carried out is handled again.The invention is characterized in less expensive secondary desulfurization method and remove (S) in the molten iron significantly, just do not alleviate steel making working procedure desulfurization task, main is the load that alleviates high cost desulfurization in the blast furnace, reduce slag basicity and reduce slag iron ratio, blast furnace can be freed from high flow rate, low output, poor benefit.
At present the method for external desulfurization of hot metal has: with sweetening agent in trough spreading method with add the plane flow method continuously, vortex motion or machinery or induction stirring or rotating cylinder rotary method etc., or add skimmer desulfurization slag is separated with molten iron, in iron ladle, have and add suspension system behind the sweetening agent, machinery or gas blow mixing method, airlift pump method, also have blowing desulfurization agent method, insertion bell jar or fire-resistant insertion rod to immerse sweetening agent method, tank switching method, vacuum method, electrolytic process etc., or its different methods make up mutually.Desulfurizer therefor comprises Su Da powder, NaOH, lime powder, Ca (OH)
2, rhombspar, Wingdale, powdered carbon, graphite, CaC
2, calcium cyanamide, colemanite, fluorite, CaCl, Al
2O
3Desulfurization dephosphorization synthetic slag, propane, magnesium grain, magnesium coke, magnesium alloy etc. and the different mixture of forming thereof, or add some addition agents promotions or buffering desulphurization reaction in addition.Popular effective desulfurizing iron method is spray into lime series sweetening agent in iron ladle after, metering sprays into magnesium or lime, magnesium mixed sweetening agent again, with utilization ratio and the comprehensive deep desulfuration efficient that improves magnesium, obtained good sweetening effectiveness (two zero is following).But facility investment is big, and it is less to be not suitable in China most producers iron ladle again, and hot metal temperature drop is big, physical conditions such as prerssure on transport.If it is big to make full use of blast furnace discharge yard, distance flows, and occupy the high good dynamic conditions of this process of tapping a blast furnace of iron ladle that pours, behind skimmer, emit sweetening agent the The Small Well top of molten iron evenly to be sprinkled into continuously with molten iron stream, make sweetening agent with the molten iron trough of flowing through, occupy height again and pour iron ladle, so just make the comprehensive engagement substantially of sweetening agent and molten iron.Its mixing effect of evidence is not second to jetting in the jar, and invests little instant effect, do not need the flower great amount of investment and builds the desulfurization station, all successful implementations in a short time of general producer, therefore this secondary desulfurization method of special recommendation here.It is characterized in that the lime series sweetening agent of cheapness is spread equably continuously or sprays on the molten iron that The Small Well behind the skimmer is emerged, or at each iron ladle molten iron stream place of chewing or establishing the storage molten iron or do not storing molten iron formula skimmer to shunting molten iron place, each iron ladle position, or at the storage molten iron or after not storing molten iron formula skimmer, evenly spread or spray sweetening agent continuously to molten iron stream again, or add magnesium or magnalium, magnesium calcium, magnesium alloy such as magnesium manganese, or do not establish the storage molten iron or do not store molten iron formula skimmer, remove slag in the iron ladle to steelworks with slag removal machine or alternate manner, or when molten iron is poured out iron ladle, establish a grade slag device shelves slag, desulfurization slag is separated with molten iron.The same about method from magnesium coke to iron ladle that add magnesium or magnesium alloy,, many now with the method for spraying into or insert bell jar or fire-resistant insertion rod immersed method with the spray lime powder, the complicated heaviness of equipment, operational danger is big.Calculation of thermodynamics and test show that all the vapour pressure of magnesium under the molten iron temperature is quite big, and sharply a large amount of magnesium vapors that produce can be blasted, and with the molten iron splash outside iron ladle.Therefore because long more utilization ratio of magnesium desulfidation time is high more, add magnesium from trough in addition, just have more superiority to desulfurization slag is separated before steelworks is gone into steel melting furnace with molten iron.So recommend here liquid magnesium or its alloy are cast into the porous cast iron piece, again its porous mouth is inserted downwards in the trough, with the size in hole with put into the magnesium vapor generation speed of how much controlling of ingot pig a suitable level.Make magnesium flow through long trough with molten iron, occupy height and pour iron ladle, reaction for a long time in being transported to steel mill's process more so just can obtain with above-mentioned magnesium or magnesium alloy are immersed the same effect of iron ladle.For prevent that porous casting magnesium ingot pig from floating in trough, polylith can be built, or the porous cast iron piece be made vertical, have certain altitude, stand in the trough.The porous cast iron piece can be got iron on the spot and be made by the special messenger in the stokehold, need not outsourcing, does not also get rid of certainly and uses other porous iron block or iron alloy block.Perhaps liquid magnesium or magnesium alloy are cast in the set porous refractory brick blocks, insert its porous mouth in the trough downwards after the cooling, add certain pressure on it, in case in trough, float, or make vertical porous casting magnesium refractory brick blocks, or add certain pressure thereon again with certain altitude.This porous refractory brick blocks can be used repeatedly.The used magnesium material of magnesium that is cast into or magnesium alloy can use crude magnesium (system magnesium intermediates) to replace, to reduce cost.The simple desulfuration efficiency height of this method can make blast furnace molten slag basicity reduce significantly.
Except that from smooth operation of furnace, the needs of the desulphurization reaction between the slag iron also are main to existing smelting process to the requirement of viscosity coefficient of dross.AL
2O
3Content basicity of slag (binary) or total alkalinity (ternary) more for a long time also requires higherly slightly, and this just certainly will make the quantity of slag increase, and makes blast furnace increase depletion and imitates.
Slag can from the smooth effusive peak viscosity of blast furnace be 20～25 the pool (P) (2.0～2.5Pa second).In the actual measurement finishing slag flows out 1350～1550 ℃ of outer temperature ranges of stove, can both meet above-mentioned viscosity requirement with the slag of the most of compositions shown in figure below, the table (stroke frame except).Accompanying drawing 1 is slag pairing viscograph under differing temps of 1 group of interior each slag different components in the table; Accompanying drawing 2 is slag pairing viscographs under differing temps of 2 groups of interior each slag different componentss in the table; Accompanying drawing 3 is slag pairing viscographs under differing temps of 3 groups of interior each slag different componentss in the table; Accompanying drawing 4 is slag pairing viscographs under differing temps of 4 groups of interior each slag different componentss in the table; Accompanying drawing 5 is slag pairing viscographs under differing temps of 5 groups of interior each slag different componentss in the table; Accompanying drawing 6 is slag pairing viscographs under differing temps of 6 groups of interior each slag different componentss in the table; Accompanying drawing 7 is slag pairing viscographs under differing temps of 7 groups of interior each slag different componentss in the table.Some low MgO synthetic slag suitably increases a part of MgO again, still can further improve its thermostability and chemical stability.Blast furnace slag from basicity and total alkalinity MV minium viscosity district all between 0.8～1.2 (dual alkalinity) and 1.2～1.4 (total alkalinitys).Basicity is in the scope of 0.9-1.2, and increasing its stability of suitable MgO (5-15%) can be quite a lot of.Yet basicity can be better less than 0.9 stability.Just can not consider its sweetening power fully in this case, because there is the secondary desulfurization of above-mentioned cheapness to guarantee.Only slag compositing range is the first crystalline region of melilith, magnesium rose stone, monticellite at the quaternary slag system.In ternary is the first crystalline region of wollastonite, rankinite and gehetinite.Certainly concrete suitable basicity is still needed according to former, the fuel situation of each department, further determines through the production practice of laboratory test and blast furnace.
Method with above-mentioned cheap sweetening agent secondary desulfurization can make blast furnace slag basicity reduce at least more than 0.1 as calculated, and furnace processor will improve 2.5-3.5%, and comprehensive coke ratio reduces more than the 2.5-3.5%.
Low such as the bit comparison of the present used iron ore product of Anshan iron and steel plant iron work, SiO in the iron ore gangue
2Content shows general slag basicity 1.11 up to (only being 1-4% in the rich ore) more than the 7-10%.Resemble 3 like this
#Blast furnace slag iron is than up to (abroad be 300kg/Tp about) about 600kg/TP.Iron ore, flux, fuel are brought AL into
2O
3Account for 8.5% for about 50kg/TP, stable is about 45kg/TP with MgO content 7.2%.Make dual alkalinity CaO%/SiO if reduce CaO
2% is 1.0, and (S) only is elevated to 0.025% from 0.019%, is one-level sulphur molten iron still≤0.03%, adds also the have substantial degradation potentiality of slag basicity of secondary desulfurization.That is to say that the blast furnace ironmaking slagging regime can not consider the desulfurization by slag problem fully, desulfurization is placed on outside the stove, and the reduction amplitude of slag basicity will far surpass 0.1, and increase output and reduce and consume also far away from more than 2.5～3.5%.When the time comes, the problem of slag etch furnace lining has not just existed, and alkali-metal function is also bigger in the slag discharge stove, and prepurging has not needed yet, and adds not consider desulfuration in furnace, only needs the low temperature smooth running, and blast furnace will obtain once big liberation.
For reducing slag basicity, the burden structure that the Anshan iron and steel plant blast furnace can adopt: one, two row's blast furnaces (7
#Except the blast furnace) can consider with acid, the two ball agglomerate of alkali, or high and low basicity pellet agglomerate, the slag composition only needs according to the slag viscosity adjustment.All the other stoves can reduce the high basicity sinter consumption, if the acid pellet deficiency can suitably be replenished natural lump ore (Ru Aokuang) or acid small-ball sintering mine, so that keep lower blast furnace slag basicity.The Anshan iron and steel plant blast furnace tentatively can be reduced to basicity over and operated exhausted 1.05 or lower present stage, and carried out the outer separation of flow of cheap stove, so that improve blast furnace production economic benefit as early as possible.Other producer's acid burden material can consider to adopt cold bound pellet or carbonaceous pelletizing etc.
In a word, resembling Anshan iron and steel plant smelts gangue like this and contains SiO
2Than the blast furnace of higher low-grade iron ore, the economic benefit of above-mentioned novel process is conspicuous.
In order to avoid using low intensive self-fluxed sinter when reducing slag basicity, recommend a kind of novel sintered ore deposit here in addition, promptly the high-basicity agglomerate burns the acid small-ball sintering mine of folder.Also promptly in high basicity sinter folder burn acid bead, with the basicity of how much regulating of wherein high basicity sinter and acid bead consumption, or in order to obtain suitably low blast furnace finishing slag basicity.
Owing to do not consider the sweetening power of slag, carry out secondary desulfurization, just have only a restriction in the slagging regime, suitably low viscosity promptly to be arranged, melting temperature.This just formulates slagging regime for the blast-furnace smelting of various furnace charges and has created and advantageous conditions.Eliminate slag, close the fluorine rare earth slag, smelt such as baric blast furnace slag, height under many situations such as the high magnesioferrite of high alumina and haveed no alternative but adopt low Basicity Operation.Its sweetening power is lower, and as adopting secondary desulfurization, chamber test and production practice are bound to further make more suitable favourable slagging regime by experiment.
Annotate: various composition synthetic slags pairing viscograph under differing temps is seen accompanying drawing 1-7 in the 1-7 group.
Claims (6)
1, a kind of blast furnace ironmaking novel process, blast furnace ironmaking carries out smoothly for guaranteeing to smelt now, produce qualified molten iron, usually require slag that lower temperature of fusion and melting temperature and viscosity are arranged, and require to have certain high basicity, to guarantee to have enough abilities that removes sulphur in the molten iron, adopt various burden structures, generally do not carry out secondary desulfurization, or there is secondary desulfurization to carry out to indivedual off-irons or for alleviating next step steel making working procedure desulfurization task, the method of used external desulfurization of hot metal comprises: with sweetening agent in trough spreading method with add continuously the plane flow method, vortex motion or machinery or induction stirring or rotating cylinder rotary method etc., or add skimmer desulfurization slag is separated with molten iron, in iron ladle, have and add suspension system behind the sweetening agent, machinery or gas blow mixing method, the airlift pump method, also has blowing desulfurization agent method, insert bell jar or fire-resistant insertion rod and immerse the sweetening agent method, the tank switching method, vacuum method, electrolytic process etc., or its different methods makes up mutually, and desulfurizer therefor comprises Su Da, NaOH, lime, rhombspar, Ca (OH)
2, Wingdale, charcoal, graphite, CaC
2, calcium cyanamide, colemanite, fluorite, CaCl, Al
2O
3Desulfurization dephosphorization synthetic slag, propane, magnesium or magnesium alloy etc. or its different mixtures of forming, the invention is characterized in and utilize less expensive sweetening agent outside stove, to handle molten iron, remove sulphur in the molten iron significantly, thereby effectively alleviate the desulfurization load of high cost in the blast furnace, reduce slag basicity significantly, reduce slag iron ratio, and can further improve, optimize burden structure and make blast furnace subtract consumption synergy.
2, according to claim 1, the invention is characterized in the lime of cheapness series sweetening agent evenly is sprinkling upon on the molten iron that The Small Well is emerged behind the skimmer continuously, or be diverted to shunting place of each iron ladle at molten iron, or before chewing, the molten iron stream of each iron ladle establishes skimmer, or skim with other slag skimming method, or behind skimmer, spread sweetening agent again or add magnesium or magnesium alloy, or do not establish skimmer and remove slag in the iron ladle with various slag removal machines or other slag skimming method to steelworks, or when molten iron is poured out iron ladle, establish the slag-blocking apparatus pushing off the slag, desulfurization slag is separated with molten iron.
3, according to claim 1.2, the invention is characterized in that the method that adds magnesium or magnesium alloy in the trough before molten iron enters iron ladle is that liquid magnesium or magnesium alloy are cast in the good porous cast iron piece of prior casting, insert its porous mouth in the trough downwards after the cooling, or polylith is built, or be the vertical porous casting magnesium ingot pig of certain altitude, or be other porous casting magnesium iron block or iron alloy block, or with crude magnesium replace cast magnesium or magnesium alloy.
4, according to claim 1.2, the invention is characterized in that the method that adds magnesium or magnesium alloy in the trough before molten iron enters iron ladle is that liquid magnesium or magnesium alloy are cast in the set porous refractory brick blocks, insert its porous mouth in the trough downwards after the cooling, or add certain pressure thereon, or the vertical porous of making certain altitude is cast the magnesium refractory brick blocks, or add certain pressure, or with crude magnesium replace cast magnesium or magnesium alloy.
5, according to claim 1.2, the invention is characterized in the more a spot of high basicity sinter of blast furnace burden structure, be equipped with a large amount of acidic pellet ores or acid small-ball sintering mine or natural lump ore, or cold bound pellet or carbonaceous pelletizing, or without high basicity sinter, and with acid, the two ball agglomerate of alkali or high and low basicity pellet agglomerate, in order to adjust blast-furnace slag basicity, the amplitude that makes it to reduce than normal basicity of slag is more than 0.01.
6, according to claim 1.2, the invention is characterized in that the blast furnace burden structure is used in the high basicity sinter folder and burns acid bead and burn acid small-ball sintering mine with the high-basicity folder that obtains suitable finishing slag basicity, or make amplitude that blast furnace slag basicity reduces than normal basicity of slag more than 0.01.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98121520 CN1243882A (en) | 1998-08-03 | 1998-10-09 | Low-basicity less-slag iron smelting technology for blast furnace with external desulfurizing greatly of molten iron |
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| CN98118128 | 1998-08-03 | ||
| CN98118128.7 | 1998-08-03 | ||
| CN 98121520 CN1243882A (en) | 1998-08-03 | 1998-10-09 | Low-basicity less-slag iron smelting technology for blast furnace with external desulfurizing greatly of molten iron |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101775541A (en) * | 2010-03-09 | 2010-07-14 | 武汉钢铁(集团)公司 | Quake-proof construction steel with yield strength of 160MPa and production method thereof |
| CN102586547A (en) * | 2012-03-13 | 2012-07-18 | 鞍钢股份有限公司 | Production method for low-cost clean steel |
| CN103060506A (en) * | 2013-01-18 | 2013-04-24 | 莱芜钢铁集团有限公司 | Electromagnetic induction desulfurizing molten iron jar |
| CN107955855A (en) * | 2016-10-16 | 2018-04-24 | 铁东区强东冶金技术咨询服务中心 | The method of no slag gasification removing Sulfur Content in Hot Iron phosphorus silicon |
| CN111206134A (en) * | 2020-02-24 | 2020-05-29 | 本钢板材股份有限公司 | Method for improving desulfurization effect by adding limestone in molten iron desulfurization by blowing method |
| CN111996328A (en) * | 2020-10-10 | 2020-11-27 | 内蒙古赛思普科技有限公司 | Molten iron desulphurization method for smelting reduction furnace |
| CN112626296A (en) * | 2020-12-17 | 2021-04-09 | 本钢板材股份有限公司 | Method for optimizing fluidity of low-aluminum slag |
| CN113846197A (en) * | 2020-06-28 | 2021-12-28 | 宝山钢铁股份有限公司 | Method for improving desulfurization rate of molten iron |
-
1998
- 1998-10-09 CN CN 98121520 patent/CN1243882A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101775541A (en) * | 2010-03-09 | 2010-07-14 | 武汉钢铁(集团)公司 | Quake-proof construction steel with yield strength of 160MPa and production method thereof |
| CN102586547A (en) * | 2012-03-13 | 2012-07-18 | 鞍钢股份有限公司 | Production method for low-cost clean steel |
| CN102586547B (en) * | 2012-03-13 | 2013-11-06 | 鞍钢股份有限公司 | Production method for low-cost clean steel |
| CN103060506A (en) * | 2013-01-18 | 2013-04-24 | 莱芜钢铁集团有限公司 | Electromagnetic induction desulfurizing molten iron jar |
| CN103060506B (en) * | 2013-01-18 | 2015-11-04 | 莱芜钢铁集团有限公司 | A kind of electromagnetic induction desulfurization hot-metal bottle |
| CN107955855A (en) * | 2016-10-16 | 2018-04-24 | 铁东区强东冶金技术咨询服务中心 | The method of no slag gasification removing Sulfur Content in Hot Iron phosphorus silicon |
| CN111206134A (en) * | 2020-02-24 | 2020-05-29 | 本钢板材股份有限公司 | Method for improving desulfurization effect by adding limestone in molten iron desulfurization by blowing method |
| CN113846197A (en) * | 2020-06-28 | 2021-12-28 | 宝山钢铁股份有限公司 | Method for improving desulfurization rate of molten iron |
| CN111996328A (en) * | 2020-10-10 | 2020-11-27 | 内蒙古赛思普科技有限公司 | Molten iron desulphurization method for smelting reduction furnace |
| CN112626296A (en) * | 2020-12-17 | 2021-04-09 | 本钢板材股份有限公司 | Method for optimizing fluidity of low-aluminum slag |
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