CN1095108A - Coal-oxygen-ore deposit-coal-oxygen-ore-solvent compound jet iron-bathing gas-making and ironmaking - Google Patents
Coal-oxygen-ore deposit-coal-oxygen-ore-solvent compound jet iron-bathing gas-making and ironmaking Download PDFInfo
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- CN1095108A CN1095108A CN 93104740 CN93104740A CN1095108A CN 1095108 A CN1095108 A CN 1095108A CN 93104740 CN93104740 CN 93104740 CN 93104740 A CN93104740 A CN 93104740A CN 1095108 A CN1095108 A CN 1095108A
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Abstract
The invention belongs to the chemical industry metallurgical field, a kind of new technological flow of fused reduction iron-smelting.It is characterized by at same iron and bathe in the reactor,, carry out the reduction eventually of iron ore by rifle at the bottom of the multithread road and top rifle composite blowing coal-oxygen-ore deposit-flux.In gas making and smelting reduction process, when changing each injection parameter (carbon/Sauerstoffatom ratio, top rifle height, secondary oxygen flow etc.), obtain the coal gas of heterogeneity, both satisfied the requirement of prereduction of iron ore, improved the utilization of the chemical energy of coal again.When reduction finishes eventually, directly bathe blowing desulfurization agent desulfurization in the reactor, obtain qualified molten iron or half steel at iron.
Description
The invention belongs to the chemical industry metallurgical field, is a kind of novel process of fused reduction iron-smelting.This technology is with the powder-spraying metallurgical technology, and fused reduction iron-smelting technology and gas preparation technology are combined as a whole, so have multiple functions such as fused reduction iron-smelting, half steel, gas making and scrap melting.
Since the sixties in this century, many emtallurgy research workers of countries in the world are devoted to fused reduction iron-smelting Research on New and development always, promptly attempt directly to smelt the pig iron or half steel with oxygen, coal, ore.Particularly over past ten years, the exploitation of this new technology there has been great breakthrough.Kind surplus the smelting reduction process of developing at present has ten, but in essence, the melting of coal oxygen can be divided into two classes, i.e. single stage method and two step method.Single stage method is as reductive agent and thermal source with coal, iron ore directly is reduced into the pig iron or half steel in iron liquid furnace under molten state, coal dust and oxygen can spray into the iron bath from furnace bottom, furnace roof or furnace side, and iron ore and slag making material spray into molten iron from the furnace roof adding or with coal dust, in order to improve heat supply intensity, also in smelting furnace cavity or slag, be blown into oxygen simultaneously and improve post-combustion rate.Two step method is to have added one or two pre-reducing furnaces on the basis of single stage method, is thermal source and reductive agent with smelting furnace coal gas at first promptly, and and then iron ore prereduction under solid state carried out fusion reduction eventually then to a certain degree.
No matter be single stage method or two step method, most of flow processs all be unable to do without iron bath fusion reduction eventually.The required coal gas of two step method also must be bathed reactor by iron and be produced.For fluidized-bed prereduction breeze, need to be transported to iron and bathe in the reactor through injection method.In addition, owing to be blown into a large amount of coal dusts, cause in the molten iron sulphur content higher, need after desulfurization, just can be used for steel-making.Therefore we can say that it is the maincenter link of whole smelting reduction process that iron is bathed reactor.
At present, multiple smelting reduction process and reactor are being developed in countries in the world.The smelting reduction process more approaching with the present invention is Japanese SUMITOMO METAL IND KK company's coal oxygen iron bath gasification and iron-smelting process (patent No. 86229175/08635).This technology is that coal oxygen is sprayed into from the bottom that vertical iron is bathed reactor, and end rifle nozzle is by the hydrocarbon compound gas C that is blown into simultaneously
nH
mCracking heat absorption is protected, and breeze and flux spray into reactor by the top rifle from the top of reactor, and the breeze major part directly enters slag.Because breeze can not directly contact with molten iron, thereby speed of response is slower.In addition, the coal gas post-combustion rate is low, and composition should not be adjusted, slag FeO content height, and sweetening power is poor, and the quantity of slag is big, is difficult to obtain the molten iron of qualified sulphur content.
Technology of the present invention has overcome above-mentioned shortcoming, and the present invention sprays into the molten iron surface with prereduction breeze, coal dust and oxygen from furnace roof, sprays into coal dust and oxygen from furnace bottom, when furnace volume greater than 2m
3The time, also spray into secondary oxygen from the top rifle, make further secondary combustion of coal gas and control gas composition, behind the melting of coal oxygen and the gas making end and the slag that overflows, directly in stove, carry out end powder injection desulphurization refining batch processing.
Technological design of the present invention the iron of a coal-oxygen-ore deposit-ore-solvent compound jet bathe reactor, in same reactor, realize fusion reduction eventually, make the coal gas of heterogeneity, three purposes of refining desulfuration.This technology had both been utilized the chemical energy of coal fully, again the program of secondary desulfurization had been introduced this technology, thereby had saved equipment, had improved benefit, had reduced the cost of ironmaking.Can obtain desired qualified coal gas of pre-reducing furnace and the desired qualified molten iron of steel melting furnace.
For realizing the purpose of invention, the present inventor has designed top spray gun and the rifle of the premixed end of double flow duct and the supporting use of converter body in multithread road.The top rifle is divided into two kinds of water-cooled multithread road spray gun and double flow duct spray guns, the size of generally looking furnace volume, and (furnace volume is less than 2M can to adopt the double flow duct shower nozzle respectively
3) or the multithread channel showerhead (furnace volume is greater than 2M
3).
Fig. 1 is the synoptic diagram of coal-oxygen-ore deposit-ore-solvent compound jet gas making and iron making by smelting reduction iron reactor.Fig. 2 is top rifle (A) structural representation.Fig. 3 is top rifle (B) structural representation.Fig. 4 is an end rifle structural representation.(1) top rifle wherein, (2) end rifle, (3) converter type iron liquid furnace body, (4) pipe core, (5) intervalve, (6) outer tube, (7) outer endless tube, (8) annular space, (9) pipe core, (10) circumferential weld in the middle of, (11) outer endless tube, (12) inner nozzle, (13) inner nozzle, (14) lance head, (15) pipe in, (16) oxygen spray pipe, (17) outer tube, (18) inner nozzle, (19) outer nozzle, (20) outer nozzle inlet union, (21) sealing gland, (22) sealing plug, (23) premix barrel.
Fig. 1 is the structure chart of reactor, is characterized in being made up of top rifle (1), end rifle (2), (3) three parts of converter type body of heater. The top rifle is installed in the upper of furnace body (see figure 1), in order to spray oxygen-coal-ore, steam, secondary oxygen. End rifle is the premixed spray gun of dual channel, is installed in furnace bottom, in order to spray coal and ore deposit, oxygen or flux. Detailed description is arranged (Chinese patent CN91216746.7) for the structure of end rifle and performance present inventor in the patent obtaining, designed furnace bottom coaloust-oxygen gun need not the cold gas protection, and is protected by the coal dust pyrolyzing.
Fig. 2 is multiple flow passages nozzle structure schematic diagram, and central tube (4) is coal dust, the breeze runner, intervalve (5) is main oxygen channel, outer tube (6) is the second-time burning auxiliary oxygen flow way, and outer endless tube (7) is the cooling water runner, and the annular space (8) adjacent with central tube is the steam runner. Shower nozzle is formed by the red copper casting, is threaded with the body of a gun. The design of auxiliary oxygen flow way not only makes the further second-time burning of carbon monoxide, discharges more heat for the reduction heat absorption, improves the thermal efficiency, and has improved the heat transfer condition between gas-slag, and this is that the key that is different from other top rifles is deposited.
Fig. 3 is dual channel nozzle structure schematic diagram, inner nozzle (13), inner nozzle (12), spray Rifle head (14) is respectively by 2520 heat resisting steel, the 1Cr18Ni9Ti stainless steel, and red copper is made, and other parts such as middle pipe (15) are made by seamless steel pipe. Inner nozzle (13) and inner nozzle (12) be with being threaded, and oxygen spray pipe (16) and lance head (14) are with being threaded. Outer tube (17) then is weldingly connected with lance head (14).
Fig. 4 is the structural representation of end rifle, and it is described that its structure and performance see the patent of CN91216746.7 for details.
The supporting use of end spray gun and body of heater is tied a knot in furnace lining, equal being advisable in rifle premix section termination, the end and furnace bottom surface.
The raw materials used coal dust that comprises of this technology, the prereduction breeze, lime, desulfurizer powder, oxygen, nitrogen, a small amount of block coke, the granularity of powder is all below 60mesh, process implementing is crossed kind of employed other equipment such as pulverizing mill, air feed delivery system, powder injection system, the coal gas gathering system is a proven technique, does not belong to the scope of the invention.
During blow-on, the molten iron of a constant volume must be arranged in the stove, melt pool height is preferably about 1/3rd of maximum molten bath amount in the stove, and before being blended into molten iron, end rifle will constantly be blown into nitrogen, in case shower nozzle stops up.At first beginning end rifle coal oxygen mine winding-up, by the annular space coal and the ore deposit runner of end rifle, is that carrier sprays in the stove with nitrogen with broken coal dust and the breeze below 60 orders promptly, and the nitrogen with end rifle pipe core switches to oxygen subsequently.Simultaneously, the top rifle is reduced to apart from the bath surface certain altitude, the coal oxygen runner of top rifle will be kept certain nitrogen amount, in case shower nozzle stops up.When adopting Type B top rifle, after treating that furnace temperature is suitable, begin again to spray into coal dust, breeze, be blown into oxygen by middle circumferential weld (10) by the pipe core (9) of top rifle, it is normal to adjust top rifle and each injection parameter of end rifle: best furnace temperature 1500-1650 ℃, the furnace gas export temperature is less than 1700 ℃, basicity of slag R=1-3.The basicity of slag adds amount of lime by furnace roof and adjusts.Lime adds in batches, and decide on injecting velocity the pitch time that adds lime, and lime adding amount is decided on winding-up material component and basicity of slag requirement.For preventing foamy slag splash and protection furnace lining, along with lime adds the block coke of part.Carbon oxygen content is the key of operation in the fusion process control stove, so end spray carbon Sauerstoffatom ratio is C/O=1.0-2.0, top spray carbon Sauerstoffatom is than being C/O=0.8-1.6, and spray parameter colliery, top weight ratio is coal/ore deposit=1-2.
Along with the carrying out of winding-up, liquid level raises gradually in the molten bath, when melt pool height surpasses normal running and allows height, promotes the top rifle, stops top rifle winding-up, switches end rifle coal supply oxygen supply, makes to keep end rifle pipe core and annular space has suitable nitrogen flow.Behind the excessive slag of grate, be that carrier sprays into the operation that desulfurization powder carries out desulfurization by end rifle pipe core with nitrogen.Sweetening agent can be the synthetic slag of calcium oxide-based polynary slag system or other high sulfur capacities.Traditional sulfur method is undertaken by adding the lime slag making by furnace roof, because in fusion process, FeO content height in the slag, thereby slag desulfurization capacity is poor, and being blown into of coal dust, and causes in the molten iron sulphur content higher again, obtain the molten iron of low sulfur content, must in stove, add a large amount of lime and make a large amount of basic slags, just can reach the effect of desulfurization, be made in like this and bring very big difficulty in the actual production.In order to address this problem, the present invention introduces this technology with the technology of outside-stove refining dephosphorization, promptly when melting and reducing finishes, sprays into desulfurization powder by the end rifle that is contained in furnace bottom, can make molten iron desulfurization apace.In addition, slag blanket is thinner in the technology stove of the present invention, and the phosphorous vapor that part is reduced out also has little time fully to be absorbed by slag and molten iron and along with coal gas is overflowed, so the phosphorus content in the molten iron is lower than blast-melted and with the phosphorus content of the molten iron of other technology gained.
Through a large number of experiments show that under different types of raw material and burning and the different technical parameters, this technology is compared with domestic and international similar patent, better effects if, and reactor lifetime is long, the top rifle life-span can reach more than 200 hours, and the life-span of end rifle also makes (referring to lining life) greater than stove.
Preferred example:
The furnace charge of packing on example one, D100kg level thermal model fusing, Intake Quantity is 1/3 of its capacity, keeps end rifle that an amount of N is arranged in the melting process
2Feed, in case end rifle stops up.After the furnace charge fusing, beginning end coal powder injection oxygen, and reduce the top rifle and carry out top blast secondary oxygen, when furnace temperature reaches more than 1500 ℃, stop secondary oxygen, and push up the spray coal oxygen mine, injection parameter carbon-to-oxygen ratio C/O is 1.5 the end of when, spray parameter colliery, top ratio is 1.0, carbon oxygen (oxygen of main oxygen channel) atomic ratio 1.0, breeze is the fluidized-bed prereduction breeze of degree of metalization 32%, and coal dust is a datong bitumite, and basicity of slag is controlled at about 2.0, at top lance spray nozzle apart from the about 400mm of weld pool surface, every 5min gets under the technical parameter condition of gas sample analysis, in coal-oxygen-ore deposit composite blowing gas making and fusion process, in the test period of 80min in the process of the test, the gas composition analytical results of preparation is: 68-76%CO, 15-20%H
2, 1-3%CO
2, 5-7%N
2, 85%-96%(CO+H
2); Hot metal composition: C4.5-5.0%, Mn0.27-0.31%, P0.14-0.15%, Si0.3-0.4%, SO0.02-0.15%, iron is bathed strong to the reducing power of molten pig oxide compound, and the ferric oxide total amount can be controlled in below 5% in the slag.
After coal-oxygen-ore deposit composite injection gas making and the whole reduction, promptly when melt pool height increases to specified volume, mention the top rifle and stop winding-up, switching end rifle coal powder injection oxygen is the CaO-CaF that jets
2Powder carries out desulfurizing and refining, when sweetening agent winding-up amount is 20 kilograms of/ton iron.In the time of 20min, the sulphur in the molten iron has been reduced to 0.006% by 0.15%, and desulfurization degree is more than 95%.Stop end spray sweetening agent, and suitably keep end rifle certain N is arranged
2Flow is with anti-clogging plug, grate overflow slag, tap a blast furnace 2/3.Begin the operation of next stove labour then.
From the on-test to the off-test (about 4 hours), the phosphorus content in the molten iron slightly increases.
Example two, can obtain different (CO+H with oxygen flow by control rifle position
2) coal gas of content.For example on the basis of example one parameter, increase secondary oxygen flow, then can obtain 58-64%(CO+H to 1/3 of main oxygen amount
2), 28-31%(CO
2+ H
2O) coal gas had both satisfied the requirement of fluidized-bed to iron ore prereduction degree, had effectively utilized the chemical energy of coal again in iron is bathed.Test through tens of times shows that the coal oxygen top rifle life-span can reach more than hundreds of hours.
Example three, with the end of example one spray parameter carbon/oxygen ratio change into 1.0 can refine the half steel of carbon content 2.0-2.5%.
Claims (5)
1, a kind of fused reduction iron-smelting (or half steel), the technical process of gas making is characterized in that in same reactor (converter type body of heater), design and installation the top rifle in water-cooled multithread road (comprising double flow duct), rifle at the bottom of the double flow duct carries out composite blowing coal-oxygen-prereduction ore deposit-flux; The atomic ratio of adjusting top rifle injection parameter carbon and oxygen is C/O=0.8-1.6, and the colliery weight ratio is coal/ore deposit=1-2, and bath temperature is 1500-1650 ℃, the basicity R=1-3 of control slag, (R=CaO+MgO+MnO/SiO
2+ 0.55Al
2O
3+ 1.18P
2O
5), adjust end rifle injection parameter carbon Sauerstoffatom than C/O=1-2, can obtain the coal gas of heterogeneity; After reduction finished eventually, the slag that overflows sprayed into calcium oxide-based polynary slag system direct refining desulfuration with nitrogen as carrier by end rifle.
2, by the described method of claim 1, best basicity of slag R=1.5-2.0
3, press the equipment of the described method of claim 1, A is three runner top rifles, its constitutional features is: pipe core (4) is the runner of coal dust and breeze, intervalve (5) is a main oxygen channel, outer tube (6) is the secondary combustion auxiliary oxygen flow way, outer endless tube (7) is the water coolant runner, and the shower nozzle casting forms, and is threaded with the body of a gun.
4, by the described lance driving device of claim 3, the top rifle can be made up of four runners; The annular space (8) adjacent with pipe core is the water vapour runner.
5, by the described spray gun of claim 3, B is a double flow duct top rifle, and its constitutional features is to comprise: pipe core (9), inner nozzle (13), inner nozzle (12), lance head (14), middle pipe (15), outer tube parts such as (17); Pipe core (9) is ore deposit and coal runner, and middle circumferential weld (10) is an oxygen runner, and outer endless tube (11) is the water coolant runner; Inner nozzle (13) and inner nozzle (12) be with being threaded, and oxygen spray pipe (16) and lance head (14) be with being threaded, and outer tube (17) and lance head (14) are by being weldingly connected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93104740 CN1033276C (en) | 1993-05-12 | 1993-05-12 | Coal-oxygen-ore-solvent compound jet iron-bathing gas-making and iron-smelting |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93104740 CN1033276C (en) | 1993-05-12 | 1993-05-12 | Coal-oxygen-ore-solvent compound jet iron-bathing gas-making and iron-smelting |
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| Publication Number | Publication Date |
|---|---|
| CN1095108A true CN1095108A (en) | 1994-11-16 |
| CN1033276C CN1033276C (en) | 1996-11-13 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 93104740 Expired - Fee Related CN1033276C (en) | 1993-05-12 | 1993-05-12 | Coal-oxygen-ore-solvent compound jet iron-bathing gas-making and iron-smelting |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100595287C (en) * | 2003-05-14 | 2010-03-24 | Sms德马格股份公司 | Metallurgical reactor for the production of cast iron |
| CN105803147A (en) * | 2016-04-06 | 2016-07-27 | 安徽工业大学 | Method for smelting and reducing iron ores through converter steelmaking system |
| WO2018058951A1 (en) * | 2016-09-27 | 2018-04-05 | 东北大学 | Vortex mixing method for smelting reduction of iron |
| CN110305998A (en) * | 2019-06-28 | 2019-10-08 | 武汉钢铁有限公司 | The online regulation method and device of S content in a kind of reduction blast furnace gas |
| CN110975725A (en) * | 2019-12-27 | 2020-04-10 | 昆明理工大学 | Top-blown cyclone-driven topological mixing stirring reactor and stirring method |
| CN111235338A (en) * | 2020-02-26 | 2020-06-05 | 内蒙古赛思普科技有限公司 | Method for producing ultra-low trace element molten iron by using smelting reduction furnace |
| CN112094980A (en) * | 2020-08-18 | 2020-12-18 | 北京科技大学 | System and method for efficient smelting of converter through top-bottom composite powder injection |
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| CN110396435A (en) | 2019-09-03 | 2019-11-01 | 牛强 | A kind of organic solid waste blowing gasification installation of double liquid-baths |
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1993
- 1993-05-12 CN CN 93104740 patent/CN1033276C/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100595287C (en) * | 2003-05-14 | 2010-03-24 | Sms德马格股份公司 | Metallurgical reactor for the production of cast iron |
| CN105803147A (en) * | 2016-04-06 | 2016-07-27 | 安徽工业大学 | Method for smelting and reducing iron ores through converter steelmaking system |
| WO2018058951A1 (en) * | 2016-09-27 | 2018-04-05 | 东北大学 | Vortex mixing method for smelting reduction of iron |
| GB2567770A (en) * | 2016-09-27 | 2019-04-24 | Univ Northeastern | Vortex mixing method for smelting reduction of iron |
| US11091816B2 (en) | 2016-09-27 | 2021-08-17 | Northeastern University | Method for ironmaking by smelting reduction in stir-generated vortex |
| GB2567770B (en) * | 2016-09-27 | 2021-10-06 | Univ Northeastern | Method for ironmaking by smelting reduction in strir-generated vortex |
| CN110305998A (en) * | 2019-06-28 | 2019-10-08 | 武汉钢铁有限公司 | The online regulation method and device of S content in a kind of reduction blast furnace gas |
| CN110305998B (en) * | 2019-06-28 | 2021-03-16 | 武汉钢铁有限公司 | Online regulation and control method and device for reducing S content in blast furnace gas |
| CN110975725A (en) * | 2019-12-27 | 2020-04-10 | 昆明理工大学 | Top-blown cyclone-driven topological mixing stirring reactor and stirring method |
| CN111235338A (en) * | 2020-02-26 | 2020-06-05 | 内蒙古赛思普科技有限公司 | Method for producing ultra-low trace element molten iron by using smelting reduction furnace |
| CN112094980A (en) * | 2020-08-18 | 2020-12-18 | 北京科技大学 | System and method for efficient smelting of converter through top-bottom composite powder injection |
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|---|---|
| CN1033276C (en) | 1996-11-13 |
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