A kind of method of smelting metal has been described in EP-A-0174291, be the method for particulate non-ferrous metal ore in sand form of the oxidation of melting copper, lead, zinc, nickel, cobalt and tin etc., in the melting gasifier of wherein above-mentioned ore in sand form being packed into by in the formed reduction zone of the fluidized-bed of coal.When ore in sand form passed through this reduction zone, the ore in sand form furnace charge of oxidation was reduced into metal, and this metal is collected in the bottom of melting gasifier.
It shows, can help reductive oxide compound and elemental carbon to react being lower than under 1000 ℃ the temperature by the method for EP-A-0174291.Yet some problems can appear, promptly work as smelting ferroalloy, when also using elemental carbon as reductive agent as ferromanganese, ferrochrome and ferrosilicon, have only temperature to surpass under 1000 ℃ the situation and just can produce iron alloy, because this oxide compound furnace charge that reacts under comparatively high temps is quite of short duration with duration of contact of the carbon granules that forms fluidized-bed from their oxide compound.
The present invention is intended to avoid these shortcomings and difficulty, and its objective is that providing a kind of just defines the method and apparatus of kind in beginning, makes it to produce iron alloy with the bulk oxide furnace charge in a melting gasifier, as ferromanganese, ferrochrome and ferrosilicon etc.Wherein metal pair oxygen has high-affinity, so that makes it only can react with elemental carbon when temperature surpasses 1000 ℃.Method and apparatus of the present invention is specially adapted to from any bulk oxide material production iron alloy, as ferromanganese, ferrochrome and ferrosilicon.
Have a method that beginning just defines kind with this, realized above-mentioned purpose according to the present invention, in this method, the bulk oxide furnace charge under the effect of gravity by one by three layers of static coal bed of forming, these three layers are:
-by the bottom A that degassing coal constitutes, it is covered with the molten bath of as-reduced liquid metal and liquid slag,
-oxygen or a kind of oxygen-containing gas introduced middle layer B so as to produce mainly the thermal reduction gas that constitutes by carbon monoxide and
-combustion-supporting gas of carbon granule and oxygen or oxygen-containing gas is introduced top layer C.
The advantage of this method is to use the bulk oxide furnace charge of 6~50mm granularity, preferably is the furnace charge of 10~30mm with granularity.
In order to form static bed, can use granularity is that 5~100mm, particularly granularity are the suitable coal of 5~30mm.
By embodiment preferred, the thickness of the static bed at intermediary and top will remain on 1m between the 4m.
Be characterised in that according to another embodiment of the inventive method the powdered carbon granule is separated from the waste gas by static bed (reduction zone), and make these carbon granules, be preferably in the nozzle of giving the static bed of alignment of top under the hot state with oxygen or oxygen-containing gas together.
As used coal, still keeping blocky feature after being preferably in the degassing, so that it still has such size range from 5mm to 100mm in use, best size range is that 5mm is to 30mm.Should have 50% in the degassing coal that degassing back is produced at least respectively within its primary granularity 5~100mm or 5~30mm, remaining then is undersized granularity.
Employed flux is CaCO
3(Wingdale), CaMg(CO
3)
2(rhombspar) and SiO
2(quartz).
The advantage that method of the present invention presented is keeping to heat with fossil energy, in shaft furnace, carry out the whole known advantage of reduction process, for example, carry out convective heat exchange and metallurgical reaction with the elemental carbon in the static bed, this is for the reduction of cheap metal oxide compound and separately be necessary with metal and slag well.The coking of coal and the degassing can be finished under the situation that does not form tar and other coagulable compound.The gas that coal is produced when the degassing enters in the reducing gas that forms from degassing coal gasification as additional reductive agent.
The superior especially part of this method is that the reduction of the oxide compound of cheap element such as silicon, chromium and manganese etc. can finish under the situation without electric energy.Be the required energy of the may command coal degassing with a kind of simple method in the method for the invention, this be because undersized grain (less than 5mm) top along with the hot waste gas of melting gasifier is discharged from together, separates and turns back to the oxygen-containing gas blast area, here undersized grain is by the oxygen-containing gas oxidation and discharge heat.
To test be that to get some grades be that the particle of 16~20mm put it in the cell that is preheated to 1400 ℃ the degassing one hour in behavior to particle breakdown.The volume of cell is 12dm
3(decimetre
3).After then spray is cooled off with cold rare gas element, measure the distribution situation of granularity again.
The present invention further comprises an equipment of implementing the inventive method, and promptly the vertical melting gasifier of a band refractory lining has the charging bole of loading coal and bulk oxide furnace charge and the vent pipe of waste gas on the top of this melting gasifier; Have at the sidewall of melting gasifier to penetrate the conduit that coal and oxygen or oxygen-containing gas are provided respectively in the stove, then be used for collecting liquid metal and liquid slag in the bottom of melting gasifier.This melting equipment is characterised in that its inside has formed three layers of synergetic static bed A, B, C.
-the annular bustle pipe of a blast pipe arranged in the bottom of the static bed B of intermediary, by these blast pipes be blown into oxygen or oxygen-containing gas and
-at this certain distance that makes progress, be equipped with the annular bustle pipe that has plurality of nozzles in the bottom of the static bed C on top, in melting gasifier, spray into carbon granule and oxygen or oxygen-containing gas respectively by these nozzles.
Another advantage of this melting gasifier is to have adorned hot tornado dust collector on the pipeline of combustion gas, so that carbon granule is separated from waste gas.The outlet end of these hot tornado dust collector then is connected with flow line with the annular bustle pipe of dress nozzle.
Represent that with 1 cylindrical melting gasifier has refractory liner 2.The bottom of melting gasifier is used to accommodate liquid metal 3 and liquid slag 4.Go out the metal mouth and represent that with 5 slag notch is represented with 6.A charging bole 7 and the charging bole 9 that the bulk oxide furnace charge is provided that lump coal is provided is housed on the top of melting gasifier.On the molten bath of liquid metal 3 and liquid slag 4, formed static coal bed, i.e. a bottom A who constitutes by degassing coal who does not have that gas passes through; A layer top is exactly the middle layer B that is made of degassing coal that gas passes through; B layer top is exactly the top layer C that is made of lump coal that gas passes through.
Have some blast pipes to pierce into the sidewall of melting gasifier 1, promptly the annular bustle pipe by blast pipe 8 is blown into oxygen or oxygen-containing gas respectively in gasifier.These pipes are installed in the bottom that does not have the static bed B that gas passes through.
A distance on blast pipe 8, the annular bustle pipe of the nozzle 10 that penetrates melting gasifier 1 sidewall promptly is housed in the bottom of layer C, spray into the mixture of powdery carbon granule and oxygen or oxygen-containing gas thus, the waste gas that is produced in the gasifier is introduced hot tornado dust collector 12 from a dust flue 11 that is contained in melting gasifier top.
In hot tornado dust collector 12, will be suspended in powdery carbon granule in the waste gas and separate and deliver to the outlet end of hot tornado dust collector 12, a distribution device 13 will be housed here, receive each nozzle 10 that is contained on the bustle pipe by conduit 14 again.The conduit that oxygen-containing gas is caused nozzle 10 is represented with 15.Hot tornado dust collector 12 can be regulated by the degree of dust filling with distribution device 13, and the separating effect of hot tornado dust collector 12 can be influenced.Conduit 16 combustion gas by hot tornado dust collector top.
Another advantage of producing the method for iron alloy by the invention process is that coal and bulk oxide furnace charge are normally packed into by the charging bole on melting gasifier 1 top.Coal outgases in static bed C.The coal necessary heat that outgases is provided by the thermal reduction gas that rises from static bed B on the one hand, and the combustion heat of being emitted during on the other hand by the oxygen-containing gas burning carbon granules of nozzle 10 ejections is supplied with.For the vertical height of layer C is so selected, and promptly its temperature will reach 950 ℃ at least when gas leaves layer C.Guaranteed to make the cracking of tar and other coagulable compound thus.Like this, the obstructive action of the static bed C on top has not just existed, and verified in fact, the bed thickness from 1m to 4m is favourable for the C layer.Confirm that also the vertical height from 1m to 4m also is useful for static bed B.After the coal degassing in static bed C, when its collapses down, just formed static bed B.
The bulk oxide furnace charge is melted in static bed B and by elemental carbon it is reduced.The fusing and the required heat that reduces are used and are blown into oxygen-containing gas by blast pipe 8 in gasifier and provide with the degassing coal of heat of gasification, and liquid metal that produces in static bed B and liquid slag will flow downward and be collected and guide to below the static bed A.