A kind of method and apparatus of reduction iron production
Technical field
The present invention relates to a kind of method and apparatus of reduction iron production, be specifically related to the method and apparatus of the serialization production molten iron that a kind of reduction and melting process carry out at same equipment.
Background technology
Reduction iron production is the important component part of Iron and Steel Production, its principal feature is as the disposable energy and reductive agent with mill coal, the oxide compound of iron is reduced under molten state, have briquet replacing coke, flow process is short, environmental pollution is little, construction investment is few, advantages such as production cost is low, by extensively good in the industry field, the iron and steel enterprise of various countries competitively researchs and develops.The method of existing reduction iron production mainly contains COREX method (CN1010323B), DIOS method (CN1035136A), HISELT method (CN1037542A).COREX method suitability for industrialized production wherein, other two kinds of methods are still under test.But all reduction iron production technology, since aspects such as energy consumption height, production cost height, difficult and blast furnace technology competition.
Granted publication number is that the Chinese patent of CN2697565Y discloses a kind of " electric-arc furnace steelmaking continuous charging scrap preheater ", its electric arc furnace is made of body of heater and electrode, its continuous charging steel scrap preliminary heating device is made up of preheating channel, water-cooled feeding trough etc., high-temperature flue gas in the electric arc furnace and the raw material in the preheating channel directly carry out heat exchange, can improve the preheating temperature of charging, save the energy.But this method is only utilized the sensible heat in the flue gas, can't utilize the chemical energy of the CO that produces in the steelmaking process.
The applicant provides " a kind of method and apparatus of smelting iron in arc furnace " at application number for 2008100799930.5 application for a patent for invention, include body of heater, bell, electrode, feeding equipment and discharging equipment, device also comprises at least one pair of combustion chamber and at least one pair of thermophore, the combustion chamber is connected with the body of heater of electric arc furnace by Link Port, one end of thermophore is connected with the combustion chamber, and the other end is connected with blowdown system, blower fan and gas treatment equipment respectively.This application for a patent for invention makes full use of the bubbing that smelting reduction process produces, and makes the heat storage in the bubbing burning heating thermophore, by gas circulation heat is brought in the body of heater from thermophore again, and waste heat is fully used.But this process is periodical operation to be become, and adds another stove again after stove reduction is finished and reduces, and production efficiency is restricted.
Summary of the invention
For overcoming above-mentioned the deficiencies in the prior art, the invention provides a kind of method of reduction iron production, reduction and melting process are carried out in same equipment, molten iron is produced in serialization, improves reduction efficiency.Another object of the present invention provides a kind of reduction iron production device of realizing aforesaid method.
Reduction iron-smelting method provided by the invention is, the material that will reduce places reduction furnace, heating is reduced into metallic iron in the gas heating reduction zone, after the reducing metal rate reaches 40~95%, the reduction furnace product is proceeded the electric-arc heating fusing, and carry out slag iron and separate, produce the molten iron or the molten steel that directly reduces.Described gas heating reduction and two processes of electric-arc heating fusing are carried out in same equipment, utilize the heat storage in the bubbing burning liberated heat heating thermophore that produces in the reduction process in the gas heating reduction zone, bring heat into reduction furnace from thermophore by gas again and add thermal material.The described temperature that enters reduction furnace gas is 300~2000 ℃, and the material that reduced melts by electric-arc heating at furnace bottom.
Described reduced material is natural lump ore and ore agglomerates, described artificial rich ore is carbon containing dressing pelletizing, breathe shell, partly breathe shell, open wide shell, block or cellular carbon containing or non-carbon containing forming composition, the breathing shell contains the mixture of ferriferous oxide and materials such as carbonaceous material and catalyst binder or only contains ferric oxide or only contain carbonaceous material.It is sticking and form with tackiness agent that the dressing of dressing pelletizing is mainly limestone powder, rhombspar powder or silicate powder, and described tackiness agent is silicon sol, water glass, phosphoric acid or aluminum oxide, or the mixture of above-mentioned substance.
For realizing the method for above-mentioned reduction iron production, the invention provides a kind of device of reduction iron production, comprise reduction furnace, thermophore, combustion chamber, gas blower, blowdown system and pipeline that matches and valve.Reduction furnace is respectively equipped with more than one on the furnace wall, both sides of gas heating reduction zone as 1~10 air inlet port, every side thermophore is connected with reduction furnace with air inlet port by the combustion chamber, the other end of thermophore is connected with blowdown system with gas blower, and the combustion chamber is provided with burner.Described reduction furnace is divided into preheating zone, heating reduction zone, slag district and melting area, and reduction furnace also comprises electrode, bell, feeding unit, air inlet port, molten iron outlet and carburized material, and described electrode is inserted into the melting area.
The reduction furnace rectangular configuration that is as the criterion is provided with more than 1 as 3 electrodes in the described reduction furnace body of heater, described electrode is DC electrode or ac electrode; Electrode is that Graphite Electrodes also can be the electrode of other form, and Graphite Electrodes scribbles the protection against oxidation layer outward.Corresponding one group of thermophore of a plurality of air inlet ports of reduction furnace one side and combustion chamber or each air inlet port be corresponding one group of thermophore and combustion chamber separately.Another form of described reduction furnace is that every side is provided with the two rows air inlet port, and every row is provided with 1~10 air inlet port, and described combustor exit connects by the upper and lower respectively two row's air inlet ports of T-valve.Described roasting kiln is provided with geseous fuel burner or liquid fuel burner or solid fuel burner or peripheral fuel burner, or the combination of above-mentioned burner, according to arts demand can refuel also not refuel or add sometimes sometimes do not add.
Reduction furnace also can be designed as, and the top is provided with two plasma guns, is provided with partition wall in the reduction furnace, and the top of partition wall is provided with gas passage, and affiliated partition wall is the fire-resistant brickwork construction of fire-resistant brickwork construction or water-cooled interlayer.Heat storage in the described thermophore is that ceramic refractory, metallic substance or the material itself that is reduced are made heat storage.Heat storage be shaped as spherule, cuboid or cellular polyhedron.
Described device also is suitable for calcium carbide production process, and yellow phosphorus and phosphoric acid are produced the chemical process that waits other carbon reduction; Producing calcium carbide is raw material to breathe shell, breathes in the shell and only is made up of carbonaceous material and catalyzer, breathes the shell shell and mainly is made up of lime carbonate.Be heated to 1100~2100 ℃ by the gas heating district, enter in the calcium carbide smelting furnace of bottom, at this moment, described reduction furnace top is that lime carbonate decomposes the district, and the bottom is the calcium carbide smelting zone.The smelting part of reduction furnace is divided into electrical heater, electric arc furnace, electromagnetic induction furnace, electroslag furnace, electroslag furnace or plasma heating furnace, or the combination between the above-mentioned type of furnace.
Compared with prior art, advantage of the present invention is: 1. gas heating reduction and two processes of electric-arc heating fusing are carried out in same equipment, can go back original production continuously, have simplified operating process, have saved equipment, improve the efficient of reduction iron production.2. utilize the heat of reduction process flue gas and the heat that contains CO bubbing burning generation that reduction process produces, the heat storage in the heating thermophore is brought heat into reduction body of heater internal heating by gas circulation and is reduced thing, makes Btu utilization reach optimizing.3. can adopt single air inlet port or double air inlet port air inlet, flexible operation.4. use the heating of three-phase alternating current electrode, power is big, is beneficial to expand production capacity.5. use Graphite Electrodes to add the protection against oxidation layer, help prolonging the work-ing life of electrode, reduce the cost of reduction iron production.Flow process of the present invention is reasonable, reduces investment outlay and hold facility, is applicable to fused reduction iron-smelting production, and also can be used for the smelting process of other metal or other need be with the reduction process of charcoal reductive metal oxide.6. form is flexible on the basis of same principle, can derive multiple type of service.7. reduce the hear rate in the reductive agent iron manufacturing process,,, also reduced pollution widely, and reduced the cost and the operational cost of whole process owing to optimized technological process to adapt to different specific requirements
Fig. 1 is a reduction iron production device schematic flow sheet of the present invention;
Fig. 2 connects vertical view for reduction furnace;
Fig. 3 is another program reduction furnace synoptic diagram of the present invention;
Fig. 4 is the vertical view of the described scheme of Fig. 3.
Fig. 5 is a third embodiment of the invention reduction furnace synoptic diagram.
Wherein:
1-valve, 2-gas blower, 3-thermophore, 4-combustion chamber, 5-bell, 6-reduction furnace, 7-preheating zone, 8-gas heating reduction zone, 9-air inlet port, 10-electrode, 11-feeding equipment, 12-slag district, 13-melting area, the outlet of 14-molten iron, 15-carburized material, 16-plasma gun, 17-partition wall, 18-passage, 19-pore, 20-T-valve.
Embodiment
The present invention is further illustrated below in conjunction with accompanying drawing.
Embodiment 1
The device of reduction iron production of the present invention mainly is made up of reduction furnace 6, thermophore 3, combustion chamber 4, gas blower 2, blowdown system and the pipeline that matches and valve 1 as shown in Figure 1.One end of thermophore is connected with reduction furnace by combustion chamber, air inlet port, and the other end of thermophore is connected with blowdown system with gas blower 2, and described blowdown system comprises fly-ash separator, induced draft fan and chimney.The combustion chamber is provided with burner, and fuel conduit and airline are connected to burner.Reduction furnace is divided into preheating zone 7, gas heating reduction zone 8, slag district 12 and melting area 13.Reduction furnace also comprises electrode 10, bell 5, air inlet port 9, apparatus for feeding 11, molten iron outlet 14 and carburized material 15, and electrode is inserted into melting area 13.As shown in Figure 2, the reduction furnace cross section rectangular configuration that is as the criterion, reduction furnace is inserted with three ac electrodes 10, and described electrode is a Graphite Electrodes, and the outside of electrode is provided with inoxidzable coating.Reduction furnace is respectively equipped with 6 air inlet ports 9 on the furnace wall, both sides of gas heating reduction zone, the outlet of every side combusion chamber is connected to each air inlet port by adiabatic pipeline.
The process of reduction iron production of the present invention is, reduced material is inserted in the reduction furnace 6, material is for breathing shell, freezing air is by air-blaster 2, valve 1 through the left side blasts, the freezing air quilt that enters heat storage is by being heated as high temperature air through the heat storage of smoke pre-heating last time, enter the combustion chamber in left side, coal gas burner is housed in the combustion chamber, the preheating high temperature air becomes high-temperature flue gas with the coal gas mixed firing that burner sprays into, high-temperature flue gas menopause pipe line and air inlet port 9 spray into gas heating reduction zone 8 and add thermal material, finishing waste gas after the heating discharges from the air inlet port on reduction furnace right side and enters the combustion chamber, right side, because in the gas heating reduction zone, material can produce a large amount of inflammable gass in reduction process, comprise the CO that produces in the reduction process, the fugitive constituent that produces after coal is heated etc., inflammable gas enters into the combustion chamber on right side with waste gas, burner in the combustion chamber sprays into combustion air, with the inflammable gas perfect combustion in the waste gas, high-temperature flue gas after the burning enters the thermophore on right side again, flue gas with the heat transferred heat storage after, temperature reduces gradually and reduces, discharge by the thermophore afterbody, enter atmosphere through blowdown system.Along with carrying out gradually of process, the flue-gas temperature that goes out the right side heat storage raises gradually, after reaching certain temperature, entire equipment commutation work, freezing air process gas blower and valve enter the combustion chamber, right side by the thermophore on right side, freezing air is being heated to form high temperature air through behind the heat storage, with the coal gas mixed firing that infeeds in the combustion chamber, right side, the insulated piping that the high-temperature flue gas that produces is connected with reduction furnace by the combustion chamber, enter the gas heating reduction zone in the stove from the right side, add the laggard combustion chamber of going into the left side of thermal material, to discharge by the left side thermophore after the inflammable gas perfect combustion in the waste gas, entire equipment is cycle operation in this manner, makes the inflammable gas perfect combustion that produces in the reduction process, and the heat that burning produces provides energy for the thermal reduction that adds of material again.
In reduction furnace, material moves from top to bottom, through entering the gas heating reduction zone of reduction furnace after the preheating of preheating zone, the high-temperature gas that material is infeeded in this district heats rapidly, be increased to 1600 ℃ in short period of time, the inflammable gas that produces in the reduction process, both can this zone in and the surplus high-temperature air burning, also can enter the combustion chamber internal combustion with gas, the dressing pelletizing heats and the reductive process in the heating reduction zone, after pelletizing reaches certain degree of metalization, enters the melting area of reduction furnace bottom, product after will being reduced by electrode melts fully, and the molten iron after the fusing is discharged by the iron notch of reduction furnace bottom.Can place carburized material such as barren rock electrode ink at reduction furnace molten bath interior and regulate hot metal composition, make hot metal composition can reach specified requirement.
Because in the gas heating reduction zone, the gas that sprays into has oxidisability, and is at high temperature oxidized in order to prevent Graphite Electrodes, can be in the top layer of graphite brushing oxidation resistant coating.
Embodiment 2
Another embodiment of the present invention as shown in Figure 5, material on gas heating reduction zone 8 every wing furnace walls at reduction furnace middle part, is provided with two rows air inlet port 9 for breathing shell, every row is provided with 3 air inlet ports, and 4 outlets of described combustion chamber are connected with upper and lower two row's air inlet ports respectively by T-valve.During reduction furnace work, high-temperature gas goes out the combustion chamber, left side earlier, spray in the reduction furnace by furnace wall, left side lower air inlet, the high-temperature gas transverse flow adds thermal material in body of heater, the gas that adds behind the thermal material enters the combustion chamber, opposite by row's air inlet port 9 on the furnace wall, right side, after the combustion chamber was with the burning of the combustiblecomponents in the waste gas, waste gas was discharged to blowdown system through thermophore 3.The commutation of work for some time system, high-temperature gas goes out the combustion chamber, right side, and row's air inlet port sprays into stove internal heating material down from the reduction furnace right side, and the waste gas after the heating is discharged through the left side upper air-vent again, the air inlet port alternation of arranging up and down in this manner realizes that material is heated evenly.Other workflow is identical with embodiment 1, no longer repeats.
Embodiment 3
Embodiment as shown in Figure 3 and Figure 4 among the present invention the 3rd, raw material is for breathing shell, the reduction furnace roof is provided with two plasma guns 16, be provided with partition wall 17 in the reduction furnace, the top of partition wall is provided with gas passage 18, described partition wall is the fire-resistant brickwork construction of fire-resistant brickwork construction or water-cooled interlayer, the air inlet port 9 of reduction furnace is located at bottom, furnace wall, both sides, furnace bottom is provided with iron notch 14, after the reduction material is added by the top plup inlet, high-temperature gas enters reduction furnace by a side bottom air inlet port, upwards flow along burner hearth at furnace gas and to add thermal material, after waste gas arrives upper furnace, through the partition wall pore, enter an other wing furnace thorax, flow downward again and add thermal material, the waste gas that adds behind the thermal material is discharged by the pore that is positioned at the bottom, commutation work after work for some time, reach certain temperature when being heated material by gas heating, and when having certain degree of metalization, two plasma guns that are positioned at the reduction furnace top are started working, and coal dust and air are sprayed in the stove as medium, with the reduzate heat fused, the molten iron after the fusing is discharged by the iron notch that is located at the bottom.Add new breathing shell subsequently again and begin, prolonged the circulation path of high-temperature gas in reduction furnace in this way, improved heat exchange efficiency as another round-robin.After carrying out a large amount of CO heat fused material of incomplete combustion generation by plasma gun coal dust and air simultaneously; introduce the above-mentioned same body of heater of an other side from pore 19; except that material in this stove is carried out the gas shield; also can be used as fuel to material or body of heater is held body outward heat, heating efficiency is improved and reduce and pollute.
Embodiment 4 is used to produce calcium carbide
Another embodiment of the present invention is for producing calcium carbide with device shown in Figure 1, and at this moment, the district is decomposed for lime carbonate in the gas heating reduction zone 8 in the reduction furnace, and melting area 13 is the calcium carbide smelting zone.Material is breathed in the shell and only is made up of carbonaceous material and catalyzer for breathing shell.Calcium carbide production process is identical with embodiment 1, to there be the breathing shell of carbonaceous material to place reduction furnace, preheating zone at reduction furnace, the dressing pelletizing is carried out preheating, along with the carrying out that produces, material moves from top to bottom, enter the gas heating reduction zone, in this zone, the dressing pelletizing is heated to 1200~2000 ℃ by the high-temperature flue gas after being heated through heat storage, the outer lime carbonate dressing of pelletizing resolves into calcium oxide in heat-processed, and with pelletizing in the part carbon generation carbide of calcium that reacts, the CO (carbon monoxide converter) gas that generates in reaction process enters in the combustion chamber with waste gas, the air mixed burning that infeeds with the combustion chamber, the high-temp waste gas that produces is stored in heat storage with heat after by thermophore, and the heat of heat storage is taken back to reduction furnace internal heating material by thermal barrier in next one circulation heat-processed.After the dressing pelletizing of process gas heating reduction zone is heated to high temperature and the partial reduction reaction has taken place, enter the smelting zone of reduction furnace bottom, in this zone, proceed electrically heated to the complete smelting reduction of pelletizing by electrode, final calcium carbide product is discharged by the outlet that is positioned at the reduction furnace bottom.