KR101064992B1 - Apparatus for manufacturing molten irons - Google Patents

Abstract

The present invention relates to a molten iron manufacturing apparatus for allowing the collection of dust generated in a facility for compacting the reduced coal or iron ore in a reduction furnace dry-type, the molten iron manufacturing apparatus according to the present invention is a fluidized bed type for reducing iron ore A reduction furnace; A compacted material manufacturing unit for receiving compacted spectroscopically reduced in the reduction furnace to produce compacted material; A dust collecting unit having at least one cyclone to dry-collect dust generated in the compacted material manufacturing unit; The compacted material is charged and includes a melting furnace for blowing molten iron into the molten iron.

Reduction Furnace, Compacted Material, Dust Collection, Dust, Cyclone, Dry

Description

Molten iron manufacturing equipment {APPARATUS FOR MANUFACTURING MOLTEN IRONS}

The present invention relates to an apparatus for manufacturing molten iron, and more particularly, to an apparatus for manufacturing molten iron, which enables to dryly collect dust generated in a facility for compacting reduced coal and reduced iron ore in a reduction furnace.

The steel industry is a core industry that supplies basic materials to the entire industry, such as automobiles, shipbuilding, home appliances, and construction, and is one of the oldest industries that have been with human development. Steel mills, which play a pivotal role in the steel industry, use molten iron and coal as raw materials to produce molten pig iron, which is then manufactured and supplied to each customer.

In order to solve the problems of the blast furnace method, many countries around the world are putting a lot of effort into the development of the molten reduction steelmaking method.

1 is a view schematically showing a molten iron manufacturing apparatus according to a conventional molten iron reduction method, Figure 2 is a schematic view showing a compacted body manufacturing unit and a wet damper of the conventional molten iron manufacturing apparatus.

As shown in the drawings, a molten iron manufacturing apparatus according to a conventional molten iron reduction method includes a plurality of fluidized bed reduction furnace 10, a compacted material manufacturing unit 100, a compacted material storage tank 50, and a melting furnace 20. . In addition, the dust collector 70 and the PSA 40 provided in the exhaust gas pipe 90 are included as needed.

In particular, the compacted material manufacturing unit 100, the storage tank 110, the compacted machine 120, the compacted iron is shredded to crush the compacted material is reduced and transported by the pressure difference 130a, 130b , Conveyor 140 for moving the crushed compacted material to the compacted material storage tank 50 in a high temperature state. And, dust collecting conduits (200,300) dust collected in the compacted material manufacturing unit 100, the wet dust collector 400 to finally process the collected dust and the fan 500 to provide the suction force required for dust removal Consists of.

Referring to the method of removing the dust by the wet dedusting machine 400, the dust passes through the wet dust collector 400 installed in the front of the fan 500, where the reduced spectroscopy is collected by the process water is transferred to the water treatment process do. The degree of dust removal is determined by the fan suction power. If the fan suction power is lowered, the generated dust is not completely removed, and when the fan suction power is increased, even unwanted relatively large particles are generated. When dust is removed, ambient air is inhaled together, which causes a problem of reoxidation of some dusts.

In addition, the above wet dedusting method requires the use of process water required for dust removal, requires a water treatment facility for treating sludge in the process water, and has a disadvantage in that water-containing sludge is discharged as a final product. Particularly, the dust treated by the wet dedusting method is discharged into the sludge containing water, and thus, there is a problem in that it has to go through a drying process in order to be recycled in its own process or another process.

The present invention has been made to solve the above-mentioned problems, and in the molten iron manufacturing process using ordinary coal and iron ore to collect the dust generated in the compacted material manufacturing unit by dry to reduce the amount of sludge generated in the entire molten iron manufacturing process It provides a molten iron manufacturing apparatus that can reduce the scale of the water treatment equipment, sludge treatment equipment of the molten iron manufacturing process through.

The molten iron manufacturing apparatus according to the present invention and the fluidized bed reduction furnace for reducing iron ore; A compacted material manufacturing unit for receiving compacted spectroscopically reduced in the reduction furnace to produce compacted material; A dust collecting unit having at least one cyclone to dry-collect dust generated in the compacted material manufacturing unit; The compacted material is charged and includes a melting furnace for blowing molten iron into the molten iron.

The dust collecting unit is provided with a dust collecting conduit to move the dust generated in the compacted manufacturing unit, the cyclone is provided in the dust collecting conduit, characterized in that the dust storage is provided with the dust collected in the cyclone It is done.

The dust collecting unit is characterized in that the dust collecting conduit is further provided with a wet dust collector in which the dust passing through the cyclone is collected.

The dust collecting unit is characterized in that the dust collecting conduit is further provided with a bag filter for collecting the dust passing through the cyclone.

Injecting nitrogen at room temperature into the dust collection conduit of the cyclone end is characterized in that the temperature of the bag filter is 200 ℃ or less.

The dust collected by the bag filter is stored in the dust reservoir.

According to the present invention, it is possible to reduce the dust generated in the compacted material manufacturing unit by installing a cyclone device as a dry equipment, and finally to collect the dust by the method by dry dust collection, thereby reducing the amount of sludge generated have.

In addition, there is an effect that can reduce the amount of process water used for wet dust collection.

Such sludge generation and process water consumption reduction can reduce the size of the water treatment equipment as a result, and can improve the water quality of the process water.

In addition, since the dust is discharged into the dust instead of the sludge generated during the wet dust collection there is an advantage that the dust is easy to recycle.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail.

3 is a view schematically showing a compacted material manufacturing unit and a dust collecting unit of the molten iron manufacturing apparatus according to the present invention.

1 and 3, the molten iron manufacturing apparatus according to the present invention is a plurality of fluidized bed reduction furnace 10, compacted material manufacturing unit 100, dust collecting unit 600, compacted material storage tank 50, the melting furnace ( 20). In addition, a dust collector 70, a compressor 80, and a gas extraction unit 40 provided in the exhaust gas pipe 90 are included as necessary.

The molten iron manufacturing apparatus manufactures molten iron by directly using iron ore and coal collected from the mountain region.

Reduction furnace 10 is a means for producing reduced iron by reducing the iron ore with a reducing gas, by supplying iron ore to the reduction furnace 10 to flow iron ore in the reduction furnace (10). Iron ore can be used as iron ore, if necessary, can be used by mixing the side materials. A fluidized bed is formed inside the reduction furnace 10 to reduce iron ore. The reduction furnace 10 includes a first reduction furnace 11, a second reduction furnace 12, a third reduction furnace 13, and a fourth reduction furnace 14. Although four reduction furnaces are shown in this embodiment, one or more reduction furnaces may be used. In addition, although the fluidized bed reduction furnace is illustrated in this embodiment, this is for illustrating the present invention and the present invention is not limited thereto, and other types of reduction furnaces may be used.

The first reduction furnace 11 preheats the iron ore with the reducing gas discharged from the second reduction furnace 12. The second reduction furnace 12 and the third reduction furnace 13 preliminarily reduce the preheated iron ore. The fourth reduction furnace 14 finally converts the preliminarily reduced iron ore into reduced iron.

Iron ore is reduced and heated while passing through the reduction furnace (10).

The reducing gas supplied to the reduction furnace 10 is the gas generated and discharged from the melting furnace 20 is supplied to the reduction furnace 10 through the reduction gas supply pipe 30. At this time, in order to prevent the fine powder contained in the reducing gas discharged from the melting furnace 20 is scattered to install a dust collector (60). Therefore, the fine powder is collected by the fine dust collector 60 and flows back into the melting furnace 20. The differential dust collector 60 may be used for example cyclone equipment.

Iron ore is reduced by reducing gas in the reduction furnace 10 is made of reduced iron. The reduced iron is transferred from the compacted material manufacturing unit 100 and then manufactured into compacted material.

The compacted material manufacturing unit 100 is a spectroscopic reservoir 110 in which reduced spectroscopy is transported and stored by a pressure difference, a compacted machine 120 for compressing and compacting the spectra into a compacted material, and shredding the compacted compacted material into a desired size. And a conveyor 140 for transferring the crushed compacts 130a and 130b and the crushed compacted material to the compacted material storage tank 50.

In this case, the shredders 130a and 130b may include a plurality of shredders in order to break the compacted material into a desired size. At this time, the screen 150 is installed between each of the crushers (130a, 130b) to sort and crush the compacted material having a size of more than the desired size. In addition, transfer conduits 160a and 160b are installed between the shredders 130a and 130b and the conveyor 140 to prevent dust generated during the shredding and transportation of the compacted material to the outside.

The compacted material manufactured in the compacted material manufacturing unit 100 is transferred through the conveyor 140 and stored in the compacted material storage tank 50.

The compacted material storage tank 50 temporarily stores the compacted material and charges the compacted material into the melting furnace 20.

The melting furnace 20 is a means for manufacturing molten iron by melting charged compacts. In addition, the melting furnace 20 is charged with a bulk carbonaceous material to form a coal filling layer together with the compacted material. The bulk coal material includes lump coal or coal briquettes. Coal briquettes are manufactured by press-molding pulverized coal. In addition, coke may be charged as needed.

When the coal filling layer is formed in this way, oxygen is blown into the melting furnace 20. Oxygen is blown into the coal packed bed to form a combustion zone, and compacted material is burned in the combustion zone to generate reducing gas. As the compacted material is burned in the combustion zone, molten iron is manufactured to produce molten iron, and the molten iron is discharged to the outside of the melting furnace 20.

The fine gas is discharged from the first reduction furnace 11 through the exhaust gas pipe 90. Therefore, the fine powder is collected using the dust collector 70 installed in the exhaust gas pipe 90, and only the exhaust gas is discharged through the exhaust gas pipe 90. After the fine powder is removed, only the desired gas is removed from the gas extraction unit 40 and then supplied back to the reduction furnace 10 to be used as the reducing gas.

The gas extraction unit 40 may be, for example, a pressure swing absorber (PSA).

In addition, the present invention includes a dust collecting unit 600 for collecting the dust generated in the compacted material manufacturing unit 100 dry.

The dust collecting unit 600 is provided with dust collecting conduits 200 and 300 through which dust generated in the compacted material manufacturing unit 100 is moved, and at least one cyclone 610 is provided in the dust collecting conduits 200 and 300. A dust reservoir 620 is provided in which dust collected in the cyclone 610 is stored.

In addition, the dust collecting conduits 200 and 300 are further provided with a wet vibration damper 400 for collecting dust passing through the cyclone 610. Thus, the cyclone 610 collects a part of the dust, and then the remaining dust is collected in the wet deduster 400.

The cyclone 610 is a dry device that collects the desired dust using a centrifugal force, and the dust collected in the cyclone 610 is stored in the dust storage 620 and then a pug mill 630. Is discharged to outside. Here, in consideration of the efficiency of the cyclone 610, the differential pressure of the cyclone 610, maintenance of equipment, and the like, it is preferable that two cyclone 610s are installed. The reason for this is that when the cyclone 610 differential pressure is too high, a dust collection problem may occur because the collecting conduit 300 takes a negative pressure.

Table 1 below shows the calculated values of cyclone efficiency and differential pressure according to the number of cyclones. In Table 1, the efficiency shows the values when the average particle size is 7.5 μm and 26.4 μm, respectively.

Cyclone count Efficiency (%) (7.5 μm) Efficiency (%) (26.4 μm) Differential pressure (mmAq) One 38.8 58.5 31.0 2 52.0 67.6 37.3 3 54.5 70.8 42.6

As shown in Table 1, when two cyclones 610 are installed, the amount of sludge generated by dust generation in the wet dedusting process can be reduced by 50% or more, and the amount of process water required for dust collection can be reduced. have. However, it can also be seen that other dust collectors are needed in addition to the cyclone 610 for complete dust removal.

Thus, in the present embodiment, as described above, the wet vibration damper 400 may collect dust that has passed through the cyclone 610. As the cyclone 610 and the wet vibration damper 400 are connected in series, more than half of the dust is collected in the cyclone 610 and the remaining dust is collected in the wet vibration damper 400 to be used in the wet vibration damper 400. It is possible to reduce the use of the process water, and to collect the dust in the powder state, not sludge, it is possible to improve the post-treatment efficiency of the collected dust.

4 is a view schematically showing a compacted material manufacturing unit and a dust collecting unit according to another embodiment of the present invention.

As shown in the figure, another embodiment of the present invention installs a bag filter 700 which is a dry facility, not a wet vibration damper 400, at the rear end of the cyclone 610. As a result, all dust is collected by a dry method.

At this time, the dust collection conduit (200,300) is maintained between 200 ~ 300 ℃ temperature, because some dust is in contact with the air reoxidation occurs first collect the relatively large particles through the cyclone 610, cyclone 610 As the nitrogen at room temperature is blown into the dust collecting conduit 300 at the rear end and the temperature is lowered, the bag filter 700 is prevented from being damaged by the reclaimed dust particles.

At this time, it is preferable that the temperature of the bag filter 700 is 200 ° C. or less by adjusting the amount of nitrogen blown into the dust conduit 300. The reason is that since the temperature of the dust collecting conduit 300 is maintained at 200 to 300 ° C., the temperature of the bag filter 700 is lowered than the temperature in the dust collecting conduit 300 to prevent dust from being reoxidized.

1 is a view schematically showing a molten iron manufacturing apparatus according to a conventional molten iron reduction method,

2 is a view schematically showing a compacted material manufacturing unit and a wet vibration damper of a conventional molten iron manufacturing apparatus,

3 is a view schematically showing a compacted material manufacturing unit and a dust collecting unit of the molten iron manufacturing apparatus according to the present invention,

4 is a view schematically showing a compacted material manufacturing unit and a dust collecting unit according to another embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: compacted material manufacturing unit 110: storage tank

120: compaction machine 130a, 130b: shredder

140: conveyor 600: dust collecting unit

610 cyclone 620 dust storage

700: bag filter

Claims (6)

A fluidized bed reduction furnace for reducing iron ore; A compacted material manufacturing unit for receiving compacted spectroscopically reduced in the reduction furnace to produce compacted material; A dust collection conduit provided with at least one cyclone and a bag filter for collecting dust generated in the compacted material manufacturing unit in a dry manner, and dust collected in the cyclone is stored. A dust collecting unit, and a dust collecting unit for injecting nitrogen at room temperature into the dust collecting conduit at the rear end of the cyclone such that the temperature of the bag filter is 200 ° C. or less; The molten iron manufacturing apparatus including a melting furnace that is charged with the compacted material, the oxygen is blown into the molten iron, delete The method of claim 1, wherein the dust collecting unit The dust collecting conduit is molten iron manufacturing apparatus, characterized in that further provided with a wet damper is collected dust passed through the cyclone. delete delete The method according to claim 1, The dust collected in the bag filter is molten iron manufacturing apparatus, characterized in that stored in the dust storage.

Images