CN1014432B - Process and apparatus for smelting and rducing iron ores - Google Patents
Process and apparatus for smelting and rducing iron oresInfo
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- CN1014432B CN1014432B CN 88108700 CN88108700A CN1014432B CN 1014432 B CN1014432 B CN 1014432B CN 88108700 CN88108700 CN 88108700 CN 88108700 A CN88108700 A CN 88108700A CN 1014432 B CN1014432 B CN 1014432B
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- iron ore
- preheating
- prereduction
- reducing furnace
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Abstract
A method for smelting reduction of iron ore, comprises the steps of:introducing iron ore into a preheat and prereduction furnace and preheating and prereducing the iron ore, a prereduction degree being less than 30 % ; charging the iron ore, carbonaceous material and flux into a smelting reduction furnace; blowing oxygen gas, through decarburization nozzles and post-combustion nozzles placed in a top end of an oxygen lance, into the smelting reduction furnace, the top end of the oxygen lance being located so as to be between a top level and a bottom level of a slag layer; blowing a stirring gas through side tuyeres placed in a side wall and bottom tuyeres placed in a bottom wall of the smelting reduction furnace; a top blow oxygen lance with decarburization nozzles and post-combustion nozzles;side tuyeres and bottom tuyeres.
Description
The present invention relates to smelting reduction of ion ores and produce the method for the pig iron, specifically, relate to the molten pig ore and the ferriferous method in next life of reducing in oxygen converter formula container.
Produce the shortcoming that iron needs expensive initial cost and big area to take up an area of for overcoming blast furnace process, the melting and reducing production iron processes of latest developments is just replacing blast furnace process.
In existing melting reduction iron-smelting method, iron ore is used earlier waste gas prereduction, then with the iron ore after the prereduction with carbonaceous material and the fusing assistant reduction furnace of packing into.In reduction furnace, be blown into oxygen and stir gas.Carbonaceous material is dissolved in the liquid pig iron of packing in advance, and the carbon in the carbonaceous material is by dioxygen oxidation simultaneously.The heat of utilizing this oxidizing reaction to produce, iron ore melt and formed liquid pig iron by the carbon reduction in the carbonaceous material bathes.The CO gas that produces during liquid pig iron is bathed burns into CO afterwards with the excessive oxygen that blows into
2CO
2Sensible heat in the gas is transferred to liquid pig iron and is bathed in the slag blanket and iron particle on surface, transfers to liquid pig iron again and bathes.
In above-mentioned technological process, iron ore reduction becomes molten pig iron.For alleviating the reduction load in the fusion reducing furnace, before fusion reducing furnace that iron ore is packed into, the reduction degree of iron ore elder generation prereduction to 60～75%.Therefore, the waste gas that requires fusion reducing furnace to produce is the suboxide degree, be high reductibility, and quantity wants big.
An object of the present invention is to provide the method for melting and reducing iron ore, in this technological process, improved heat transfer efficiency; Produce excessive energy for having reduced productive expense and having kept the reasonable energy balancing control; Also reduced the restricted condition of operation in addition.
The production pig iron method of melting and reducing iron ore provided by the invention comprises the steps: iron ore sent to and makes iron ore preheating and prereduction at least one preheating and the pre-reducing furnace, and the prereduction degree is lower than 30%;
With iron ore, carbonaceous material and the fusing assistant of preheating and the prereduction fusion reducing furnace of packing into;
By decarburization first nozzle and the oxygen blast in fusion reducing furnace of afterfire second nozzle that is contained in the top blow oxygen lance top end part, the position of the top end part of said top blow oxygen lance be on slag blanket and below between;
Be contained in the melting and reducing furnace sidewall by at least one and be blown into stirring gas with the air port that at least one is contained in the melting and reducing furnace hearth wall, stirring gas is to be selected from Ar, N
2, CO, CO
2With at least a gas in the gas that produces after the preheating precompressed reduction;
Control the flow of said oxygen and stirring gas, the oxidisability that makes the waste gas that produces in the fusion reducing furnace is between 0.4～0.9, the temperature of waste gas is between 300～1300 ℃, and said waste gas is used to send at least one preheating and pre-reducing furnace, said herein oxidisability formula (H
2O+CO
2)/(H
2+ H
2O+CO+CO
2) expression.
In addition, the equipment provided by the invention that is used for above-mentioned qualification method comprises:
At least one preheating and pre-reducing furnace that preheating and pre-reduced iron are mining, iron ore prereduction degree is lower than 30%;
The preheating prereduction iron ore of packing into, the fusion reducing furnace of carbonaceous material and fusing assistant reduces the iron ore of preheating prereduction in this stove;
Decarburization is housed with first nozzle and the afterfire top blow oxygen lance with second nozzle, oxygen is blown into fusion reducing furnace by these nozzles;
Be contained at least one air port and at least one air port that is contained in the melting and reducing furnace hearth wall of melting and reducing furnace sidewall, stir gas and be blown into fusion reducing furnace by these air ports.
In conjunction with the accompanying drawings, referring to following detailed description, other purpose of the present invention and advantage can become clearly.
Fig. 1 is an embodiment synoptic diagram of melting and reducing iron mine apparatus of the present invention.
Fig. 2 is the cross sectional illustration figure of gas flow in the fusion reducing furnace of pie graph 1 an apparatus shown part.
Fig. 3 is the explanatory view of position relation between at least one sidewall air port of the present invention and the air port, the end.
Fig. 4 represents the level height of top blow oxygen lance among the present invention and the relation between the heat transfer efficiency.
Fig. 5 represents the relation between the side-blown gas and heat transfer efficiency among the present invention.
Fig. 6 represents the oxidisability of waste gas among the present invention and the relation between the excess energy.
When in order to alleviate in the fusion reducing furnace reduction load, and before the fusion reducing furnace of packing into, the top reduction degree of iron ore is set at 30% or when slightly many, just needs to reduce the oxidizability of Exhaust Gas from fusion reducing furnace. Term used herein " oxidizability " is abbreviated as " OD " later, and OD is formulated as
（H
2O+CO
2）/（H
2+H
2O+CO+CO
2). If OD reduces, the emission gases amount increases certainly, and this disclosed, such as Japan Patent 43406/86. The energy that the result produces in fusion reducing furnace surpasses 12.6 lucky joule/liquid pig irons per ton, thus from be included in one the steel mill ironmaking and the angle of the overall energy balance of steel rolling, the energy that produces is too many. The shortcoming nature causes production cost to raise on such energy balance.
In addition, when the prereduction degree is 30% or higher, need low OD value emission gases, the time of staying of iron ore in preheating and pre-reducing furnace has to elongated. As a result, the prereduction iron ore pack into fusion reducing furnace and the discharging liquid pig iron balance be difficult to keep. This difficulty causes that the operation of fusion reducing furnace has several requisite restrictive conditions.
The method of prior art has the measure that increases iron ore melting speed, its objective is the reduction rate that iron ore is provided, and wherein the CO gas in the fusion reducing furnace is finished after-combustion, to utilize the heat that produces, for keeping above-mentioned burning, O2Gas is blown in the fusion reducing furnace by a upper wall air port of fusion reducing furnace. Method accordingly, if improve after-combustion speed, temperature of exhaust gas raises, this is that the result has to discharge high-temperature gas because the measure of sensible heat of after-combustion not being shifted has reduced heat transfer efficiency. The result is because high-temperature discharge gas is with heat to produce serious problems, and the refractory lining of fusion reducing furnace inwall is badly damaged. , it is generally acknowledged that oxidizability can not be mentioned such height for this reason.
(1) based on the fusion reduction reaction research on mechanism with for improving the measurement result of heat transfer efficiency and promotion iron ore reduction, the inventor finds:
As above-mentioned, the basic concept of prior art is that owing to the technical restriction that improves heat transfer efficiency and by the harm of after-combustion erosion to the fusion reducing furnace inwall, after-combustion speed does not have very big adjustment leeway. But, oxygen is blown into slag blanket, and simultaneously strong mixing slag blanket, after-combustion is just carried out at slag blanket like this, just can obtain the after-combustion of height and can improve simultaneously heat transfer efficiency. Like this because the after-combustion of high level has been arranged, the iron ore in slag and the slag just by heat to high temperature, can effectively be improved by the iron ore reduction speed shown in the formula hereinafter described. Following formula C represents to be contained in the C in the liquid pig iron.
(2) in several examples of prior art, in whole period of restoring operation or part period, carry out continuously bottom blowing oxygen. To after-combustion, BOTTOM OXYGEN is very disadvantageous like this. In other words, when carrying out BOTTOM OXYGEN, produce a large amount of CO gas in the liquid pig iron, simultaneously strong mixing liquid pig iron. As a result liquid pig iron splash enters the after-combustion district, and the C in the pig iron of splash and oxygen reaction have reduced the after-combustion rate thus. Therefore, the when phase in office, must avoid BOTTOM OXYGEN.
Based on these knowledge and experiences, determine following condition, the present invention can provide very fast restoring operation.
(1) is used in combination side-blown and bottom blowing and stirs gas, make liquid pig iron be diffused into energetically the slag blanket district that iron ore exists, utilize this diffusion to promote because the ore deposit reduction that the C that liquid pig iron contains carries out.
(2) decarburization nozzle and after-combustion nozzle are contained in top blow oxygen lance Top, oxygen are blown in the fusion reducing furnace by them, and the result obtains predetermined or higher OD degree. Oxygen is sent into slag blanket and is formed herein the zone of carrying out after-combustion by the after-combustion nozzle. With side-blown strong mixing slag blanket. The heat that is produced by after-combustion like this is transferred to iron ore.
(3) as the stirring and the vector gas that are blown into from sidewall and diapire, can use at least one place in the following gas, Ar, N2、CO、CO
2With the gas that produces after the preheating prereduction, can not reduce like this reduction and the after-combustion speed of institute's carbon containing in the liquid pig iron.
Referring to accompanying drawing, an embodiment of the present invention is described.Fig. 1 is the synoptic diagram of melting and reducing iron ore equipment used of the present invention, makes floated preheater as preheating and pre-reducing furnace.The meaning of two C is that each of this two C interknits among Fig. 1, and the meaning of two D also is that each of this two D interknits.In fusion reducing furnace 10, form liquid pig iron bath 11 and slag blanket 12.On fusion reducing furnace top first chute 13 is housed, in stove, loads iron ore, carbonaceous material and fusing assistant, top blow oxygen lance 21 vertical insertions wherein by this groove.At the top blow oxygen lance top decarburization first nozzle 22 and afterfire second nozzle 23 are installed,, the 3rd nozzle 24 are installed in stove, to be blown into iron ore, carbonaceous material and fusing assistant particulate or powder in top center so that oxygen is blown in the stove.In addition, sidewall and diapire difference installation side air port 25 and air port, the end 26 at stove 10 are blown in stove as the Ar, the N that stir gas by these air ports
2, CO, CO
2Or the gas that produces after the preheating prereduction.As pressurization and transmitting device setting pressure equipment 27, carrier gas and iron ore fines or powder mixes resulting mixture are blown into mixture in the fusion reducing furnace by crosswind mouth 25 and air port, the end 26 again.
Adorn floated preheater 30(on stove 10 tops and be called SP later on), as preheating and pre-reducing furnace, mainly carry out the iron ore preheating.SP30 is a multiple-unit equipment, and there is the cyclone of multistage arranged vertical every unit, hot switching path and conduit.In the embodiment of Fig. 1, as an example, the first module of SP30 has first cyclone 31, first hot switching path 32 and first conduit 33, and SP30 is triple unit by this, that is, and and unit 1,2 and 3 one-tenth arranged verticals.Unitary sequence number can be determined according to the order of loading raw material, places the hot switching path 40 of high bit location 3 that second chute 45 is arranged, and sends into the iron ore coarse grain by this groove from starting material hopper (not showing Fig. 1).
Then, narration is by the method for the melting and reducing iron ore of above-mentioned fusion apparatus use.The raw material iron ore installs to SP30 by chute 45.Iron ore particle size by this method can be determined by the capacity of SP30.
The waste gas that produces in the fusion reducing furnace is introduced first interchanger 32, and the heat that shifts oneself by heat exchange waste gas is to iron ore, and second conduit 37 of the unit 2 of iron ore by placing 1 top, unit advances downwards.After the heat exchange, waste gas enters first cyclone 31 and separates from the iron ore of delivering to second hot switching path 36.Similar to this mode, second heat exchanger channels 36 and second whirlwind 35 of waste gas by unit 2, the 3rd heat exchanger channels 40 and the 3rd whirlwind 39 of unit 3 of reducing emits.Meanwhile, the iron ore and the waste gas that install to SP30 by second chute 45 meet, and obtain heat in flow state from waste gas in the 3rd heat exchanger channels 40.Then, lighter relatively iron ore enters the cyclone 39 and the cyclone 35 that is positioned at than the unit 2 of low level of the unit 3 that is positioned at high bit respectively with relative heavier iron ore, and separates from waste gas respectively therein.After separating, lighter iron ore and heavier the iron ore conduit 37 of the conduit 41 by unit 3 and unit 2 respectively enter the heat exchanger channels 36 that is positioned at lower unit 2 and the heat exchanger channels 32 of unit 1 downwards.Enter fusion reducing furnace by heat exchanger channels 32 or conduit 33 after iron ore preheating and the prereduction.
At least a portion has installed to the iron ore after the preheating prereduction in the fusion reducing furnace 10, carbonaceous material and fusing assistant fully stir with the liquid pig iron bath 11 and the slag blanket 12 that have formed in fusion reducing furnace with stirring gas, stir gas and are blown in the stove by air port, furnace side 25 and air port, the end 26.At least a iron ore, carbonaceous material and fusing assistant are by at least one crosswind mouth or at least one air port, the end or be contained in vertical the 3rd nozzle of top blow oxygen lance and be blown into fusion reducing furnace.To stirring gas, also can adopting another kind of technology, be about to stir gas pressurization and mix with raw material, as iron ore, the fine particle of carbonaceous material and fusing assistant, the formation mixture, again with mixture from the air port 25,26 or the 3rd nozzle 24 of top blow oxygen lance 21 be blown into.Can promote the heating and the fusing of iron ore effectively with this method, solubility promoter forms the oxidation of slag and carbonaceous material, produces to improve.In addition, by first channel 13, also be simple and efficient method to filling piece or particulate material with gravity filling raw material, it is disadvantageous loading raw material by the venting port of fusion reducing furnace, this is to load effect because the meeting of dispersing of fine particle raw material obviously reduces.Therefore, replace using waste gas outlet, preferably by first chute 13, feed in raw material in the nozzle 24 or the air port 25 or 26 that are positioned on the top blow oxygen lance 21.
Below with reference to Fig. 2～5, be described in detail gas and be blown into relation between fusion reducing furnace 10 and the reaction in furnace.Fig. 2 illustrates the behavior that is blown into gas by crosswind mouth 25 shown in Figure 1 and air port, the end 26.Among Fig. 2, oxygen-blowing gun 21 following arrows 28 and 29 represent to inject by decarburization first nozzle and afterfire second nozzle direction of oxygen respectively.DCO
2The oxygen that expression is blown into by direction shown in nozzle 22 arrows 28; PCO
2The oxygen that expression is blown into by direction shown in nozzle 23 arrows 29.In whole restoring operation, carry out by oxygen-blowing gun 21 oxygen blast in crosswind mouth 25 and air port, the end 26 operation from start to end continuously.Blowing to coact by crosswind mouth and air port, the end is diffused in the slag molten metal, the result, and blowing has increased reduction rate widely.
Originally the beginning part that is described in detail is described, new discovery according to the contriver, the main C that is contained in the molten metal that uses is as reduction of iron ore agent in the reduction slag blanket 12, the present invention is actually and actively impels liquid pig iron to be diffused into such zone, by strong mixing iron ore is flowed at the lower position of slag blanket herein, to improve reduction rate.For this purpose, be blown into stirring gas, be preferably in the inflatable parts that liquid pig iron 12 surface forms liquid pig irons, simultaneously, also be blown into stirring gas from crosswind mouth 25 by air port, the end 26, with make at least part blow side into stirring gas squeeze into the A district.Because gas is gone in side-blown, diffusing the sprinkling in slag blanket 12 of liquid pig iron of inflatable district A.The apparent specific gravity of slag blanket is generally at 0.1～0.5g/cm like this
3Between and the actual iron ore proportion of state that gathers at about 2～5g/cm
3Between.
Therefore, institute's iron-stone concentrates the lower floor that floats over slag blanket 12 in the slag.When the protuberance of liquid pig iron A broke up through side-blown stirring air-flow, the liquid pig iron 17 that breaks up was diffused into the lower region of slag blanket 12.Break up contained C reduction of iron ore in the liquid pig iron.Therefore, reduction is to carry out at a high speed.For reaching this effect, preferably allow the side-blown air-flow part A of accurate impact liquid pig iron as far as possible.In orthographic plan, the position in crosswind mouth 25 and air port, the end 26 relation satisfies (a) or (b) among Fig. 3.
Fig. 3 (a) shows the position relation when adopting single crosswind mouth 25 and air port 26, the single end, and Fig. 3 (b) shows the position relation when adopting air port 26 at the bottom of 3 crosswind mouths 25 and 3.In Fig. 3, arrow shows the direction that the crosswind mouth is blown into air-flow.Certainly, the number in crosswind mouth 25 and air port, the end 26 and position not always only as shown in Figure 3 but can not be according to deciding with the capacity of fusion reducing furnace and its output.And, need crosswind mouth 25 and air port, the end 26 and carry out the heat-flash stirring with being blown into mass air flow.Being blown into airshed can be determined according to conditions such as the liquid pig iron amount and the liquid pig iron degree of depth.Outside blowing gas stream also stirs the top of slag blanket 12 except playing diffusion, thereby forms the subsequent combustion district.This describes in detail below.
As mentioned above, the air-flow that is blown into of crosswind mouth 25 and air port, the end 26 is at least a N of being selected from
2, Ar, CO, CO
2With the gas that produces after the preheating prereduction.Preferably without O
2O not
2Reason as follows: the first, if use O
2The big gas of ratio of mixture then can bring the most basic problem as side-blown gas, has promptly broken up and enters contained C burning in the liquid pig iron of slag blanket 12 lower floors, and the reduction reaction of carrying out will be hindered, and the second, if adopt O
2, then serve as a contrast flame retardant coating on the fusion reducing furnace inwall and can be heated and damage.And as mentioned above, if sneak into O in the bottom blowing air-flow
2Too much, will produce a large amount of CO and make liquid pig iron be able to stir too consumingly.The result is that liquid pig iron breaks up and enters the slag blanket top area and reach PCO
2Be able to incendiary subsequent combustion zone (seeing the B among Fig. 2).Therefore, subsequent combustion is hindered because in the liquid pig iron contained C with should be used for the O of subsequent combustion
2Reaction has taken place.
In the present invention, the subsequent combustion zone forms and reaches simultaneously the subsequent combustion of height as shown in Figure 2 in the area B in slag blanket 12.So, in slag blanket, form subsequent combustion zone and slag blanket and be able to intensively stirred method through the side-blown air-flow again and can keep the subsequent combustion of height and obtain high heat transfer efficient because of adopting.Therefore, require in slag blanket 12, to be blown into subsequent combustion O
2To form the subsequent combustion area B therein.
Special requirement top blow oxygen lance 21 should be taken into account the top of the slag and liquid pig iron face and is placed on suitable height location.In other words, if be placed on the upper surface that any one position in the nozzle 22,23 and 24 on the top blowing oxygen air gun is higher than slag blanket 12, then the subsequent combustion zone just can not form in slag blanket and heat transfer efficiency can reduce again.On the contrary, if nozzle location is lower than the upper surface of liquid pig iron bath 11, then the subsequent combustion zone still can not form in slag blanket.Top blow oxygen lance is limited at the bottom of the slag blanket in nozzle 22,23 and 24 positions following.
Fig. 4 shows the relation between the top blow oxygen lance top height and heat transfer efficiency among the present invention, and therefrom as can be seen, the oxygen-blowing gun top can not reach good heat transfer efficient in the higher position very much from the top of the slag.With regard to abscissa, zero the right numerical tabular understands that the oxygen-blowing gun top exceeds the height on slag blanket surface, and zero left side numerical tabular understands that the oxygen-blowing gun top is lower than the height on slag blanket surface.Fig. 5 has shown the relation between side-blown airshed and the heat transfer efficiency.As can be seen from Figure 5, if crosswind mouth 25 is blown into a large amount of side-blown air-flows, but just can obtain good heat transfer efficient and violent stirring slag blanket.Result shown in the Figure 4 and 5 is to be that 50 tons melting and reducing furnace operating obtains with capacity, and liquid pig iron output is 28 tons/hour.
According to the present invention, because the heat transfer efficiency height, so can reach high reduction rate by improving OD as mentioned above.With the exception of this, owing to improved OD, so can reduce the add-on of carbonaceous material.The result is to have reduced the consumption rate of carbonaceous material, and reduced the P content in the liquid pig iron simultaneously, because most of P brings liquid pig iron into carbonaceous material.And, if OD has improved, just can promote to evaporate desulfurization, therefore can reduce the S content in the liquid pig iron.From these viewpoints, OD preferably be decided to be 0.4 or more than.Be limited on the OD 1 and OD high more good more.But, from following energy balance angle, on be defined as 0.9.If OD be 0.7 or more than, just can promote the reduction reaction in the fusion reducing furnace and needn't adopt preheating and the prereduction method of utilizing preheating and pre-reducing furnace to carry out, therefore can save the cost of equipment of preheating and prereduction.
In embodiment of the present invention, as long as operation is to carry out under the felicity condition in described OD and temperature range, the reduction degree that is used as the suspended preheater of preheating and pre-reducing furnace can not surpass 15%, the prereduction degree of preheating and pre-reducing furnace and the OD of waste gas and temperature is closely related and in fact the prereduction degree advantageously be higher than 15% and can reach 30% or below, this will be according to the specification of smelting and rducing iron ores device, and operational condition and the characteristics of feeding intake are determined.In addition, according to the aforesaid operations condition, preheating and pre-reducing furnace can be with being selected from fluid bed furnace, the fluid bed furnace of band fine powder circulating system and at least a replacement suspended preheater of jet flow pool furnace.
Another characteristics of the present invention are the energy balance that improved subsequent combustion efficient and reached whole ironworks.Referring now to Fig. 6, in order to reach this energy balance, the relation between the OD of the waste gas that produces in the available fusion reducing furnace and the iron ore prereduction degree is illustrated.
Fig. 6 shows the relation between the excess energy of the OD of waste gas in the fusion reducing furnace shown in Figure 1 and generation with line chart.Among Fig. 6, draw oblique line and partly shown the suitable energy balance zone that comprises whole ironworks.Actually shown the energy balance that contains the low volatility materials carbonaceous material, and dotted line has shown the energy balance that contains high volatile volatile material carbonaceous material, all with reference to the prereduction degree, wherein indicates with percentages.These results get with the melting and reducing furnace operating that obtains Fig. 4 and result shown in Figure 5.According to result shown in Figure 6, if OD less than 0.4, excess energy is too many and energy is slatterned.On the other hand, if OD greater than 0.9, energy-producing excess quantity can not satisfy the ironworks demand very little.As shown in Figure 6, the prereduction degree is fixed on to reach reasonably suitable energy balance below 30%.If the prereduction degree be higher than 30% in preheating and the pre-reducing furnace residence time of iron ore oversize, and as described below the restriction of operational condition is just become quite strict.
And, in art methods, when the prereduction degree is decided to be 60-75%, the iron ore residence time determines in preheating and the pre-reducing furnace, OD in the waste gas and iron ore feed intake and the liquid pig iron discharging between balancing control all become insoluble difficulty, but in the preferred embodiment of the invention, these difficulties have all obtained overcoming greatly, and for reduction equipment and process cost have also installed preheating and pre-reducing furnace additional, main purpose is the preheating iron ore.The basic imagination of An Paiing is like this, and the CO air-flow that produces in fusion reducing furnace carries out subsequent combustion as much as possible, and the heat that produces is used for removing the contained carbon of fusion reducing furnace iron ore and makes reduction of iron ore as the energy.Therefore, if OD less than 0.4, spent air temperture can not improve satisfactorily, and if surpass 0.9, equipment and process cost can obviously rise again.
Temperature when introducing preheating and pre-reducing furnace as for waste gas, if be lower than 300 ℃, iron ore just can not obtain gratifying heating, and if be higher than 1300 ℃, the resistivity against fire of preheating and pre-reducing furnace can become serious problems again.Therefore, spent air temperture preferably is decided to be 700-1100 ℃.Reason is, if be limited to 500-600 ℃, iron ore can become powdery because of reduction reduces, and when being higher than 1100 ℃, can forming the bulk material that constitutes by iron ore particle because of the bonding of the sintering of iron ore and metallic iron again and bring problem may for initiation reaction in preheating and the pre-reducing furnace or make troubles for the operation that feeds intake of the pre-reduced iron ore of fusion reducing furnace.
As example of the present invention, according to preferred embodiment, can reach 0.6 and the heat transfer efficiency of OD and 95%, wherein adopt 1124Kg coal/ton liquid pig iron and 798Nm
3Oxygen/ton liquid pig iron.
Claims (7)
1, the melting and reducing iron ore is produced the method for the pig iron, iron ore is sent to make the iron ore preheating open prereduction at least one preheating and the pre-reducing furnace earlier, and the fusion reducing furnace of then iron ore, carbonaceous material and the fusing assistant of preheating and prereduction being packed into is characterized in that,
The prereduction degree is lower than 30%;
By decarburization first nozzle and the oxygen blast in fusion reducing furnace of afterfire second nozzle that is contained in the top blow oxygen lance top end part, the position of the top end part of said top blow oxygen lance be on slag blanket and below between;
Be contained in the melting and reducing furnace sidewall by at least one and be blown into stirring gas with the air port that at least one is contained in the melting and reducing furnace hearth wall, stirring gas is to be selected from Ar, N
2, CO, CO
2With at least a gas in the process gas, said process gas is the recycle gas that produces after preheating and prereduction;
Control the flow of said oxygen and stirring gas, the oxidisability that makes the waste gas that produces in the fusion reducing furnace is between 0.4～0.9, the temperature of waste gas is kept by a heat exchanger, between 300～1300 ℃, said waste gas is used to send at least one preheating and pre-reducing furnace, said herein oxidisability formula (H
2O+CO
2)/(H
2+ H
2O+CO+CO
2) expression.
2, the method for claim 1, it is characterized in that, wherein blowing the microgas flow step is to make at least a portion stir air-flow to break up the bossing that liquid pig iron is bathed in the reduction furnace, and said part stirring air-flow is blown into at least one crosswind mouth and said bossing is to use the stirring air-flow that is blown into from least one air port, the end to form.
3, the method for claim 1 is characterized in that, the operation that wherein feeds intake comprises by the chute that links to each other with fusion reducing furnace with gravity decline preheating and pre-reduced iron ore, carbonaceous material and fusing assistant.
4, the method for claim 1 is characterized in that, wherein the operation of preheating and pre-reduced iron ore is included in preheating and pre-reduced iron ore in the suspended preheater, and the prereduction degree is lower than 15%.
5, the method for claim 1 is characterized in that, wherein OD is 0.7～0.9.
6, the method for claim 1, it is characterized in that, wherein the operation of preheating and pre-reduced iron ore is included in and is selected from suspended preheater, fluid bed furnace, preheating and pre-reduced iron ore in the fluid bed furnace of band fine powder circulating system and at least one in the injection fluid bed furnace.
7, the method for claim 1, it is characterized in that, Unit the 3rd, Unit second and first module preheating and pre-reduced iron ore at floated preheater, iron ore in Unit the 3rd is by the heating by the exhaust gases and the prereduction that produce from Unit second, at the iron ore of Unit the 3rd preheating and prereduction in Unit second by the heating by the exhaust gases and the prereduction that produce from first module, and at the iron ore of Unit second preheating and prereduction in first module by the heating by the exhaust gases and the prereduction that produce from fusion reducing furnace.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62322321A JP2600732B2 (en) | 1987-12-18 | 1987-12-18 | Smelting reduction method and equipment |
| JP322321/87 | 1987-12-18 | ||
| JP62322322A JP2600733B2 (en) | 1987-12-18 | 1987-12-18 | Smelting reduction method |
| JP322328/87 | 1987-12-18 | ||
| JP322322/87 | 1987-12-18 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1035136A CN1035136A (en) | 1989-08-30 |
| CN1014432B true CN1014432B (en) | 1991-10-23 |
Family
ID=26570766
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 88108700 Expired CN1014432B (en) | 1987-12-18 | 1988-12-17 | Process and apparatus for smelting and rducing iron ores |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1014432B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL9401103A (en) * | 1994-07-01 | 1996-02-01 | Hoogovens Groep Bv | Method and device for the pre-reduction of iron compounds. |
| JP5606320B2 (en) * | 2008-09-16 | 2014-10-15 | 株式会社Ｉｓｔｃ | Manufacturing method of molten iron |
-
1988
- 1988-12-17 CN CN 88108700 patent/CN1014432B/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| CN1035136A (en) | 1989-08-30 |
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