KR100276347B1 - A fluidized-bed apparatus for reducing fine iron ore and a method therefor - Google Patents

Abstract

The present invention relates to a fluidized bed type preliminary reduction device of the iron ore in the molten reduction process for producing molten iron using a wide range of particle size ore, and to a pre-reduction method using the same. It is to provide a fluidized bed pre-reduction device and a pre-reduction method using the same to reduce the fine powder processing burden of the cyclone in the preliminary reduction of the iron ore in the melt reduction process, and also to suppress the scattering loss of the fine ore. , Its purpose is.

The present invention comprises a plurality of preliminary reduction furnace configured to reduce the iron ore while forming a bubble fluid layer; And

In the fluidized bed pre-reduction device of the iron-iron ore comprising a plurality of cyclones for collecting particulate ore contained in each exhaust gas of the pre-reduction path,

A powder flow reduction reactor configured to receive and reduce particulate ore collected in each of the cyclones; And

And a fluidized bed preliminary reduction device for iron ore, and a preliminary reduction method for iron ore using the same, further comprising a third cyclone for collecting particulate ores contained in the flue gas of the finely divided flow reduction reactor.

Description

Fluidized-bed pre-reduction device for iron ore and pre-reduction method using the same {A FLUIDIZED-BED APPARATUS FOR REDUCING FINE IRON ORE AND A METHOD THEREFOR}

The present invention relates to a fluidized bed type preliminary reduction device of iron ore in the molten reduction process for producing molten iron using a wide range of particle size ore, and to a method of preliminary reduction of iron ore using the same. Preferably, the fluidized bed pre-reduction device of the iron-iron ore and preliminary preparation of the iron-iron ore using the same in order to pre-reduce the iron-iron ore in the melt reduction process to reduce the cyclone processing burden and also to suppress the scattering loss of the fine ore It relates to a reduction method.

Until now, a method of using a blast furnace has been mainly used as a method of producing molten iron by reducing iron ore. However, in the blast furnace method, the raw material is pretreated for efficiency of the manufacturing process. In other words, the iron ore is charged into the blast furnace in the form of sintered ore produced through the sintering process in order to improve breathability and reducibility, and coke used as a heat source and a reducing agent is essential to coking strong coking coal. The pretreatment of such raw materials not only has to be equipped with ancillary equipment that requires huge investment costs, but also faces many problems with environmental regulations that are being strengthened around the world. In addition, the effective utilization of fine iron ore, which accounts for more than 70% of the world's iron ore reserves, is required, and coking coking raw material coking coal is not only low in amount but also geopolitically distributed, so the supply-demand problem of steel demand increases. have. In order to overcome the problems of the blast furnace method and use the molten iron ore and without the pre-treatment of coal, the melt reduction method has recently emerged, a representative example is US Patent No. 4,978,378.

The method described in US Pat. No. 4,978,378 can simplify the process and equipment by directly eliminating the pretreatment of raw materials such as the sintering process and the caulking process as compared to the existing blast furnace method by directly using iron ore and coal.

As shown in FIG. 1, a preliminary process of indirectly reducing iron ore by using a reducing gas generated in a molten gasifier 10 and a molten gasifier responsible for producing a reducing gas and melting a reduced ore by gasification of charged coal is performed. It can be divided into a reduction furnace 20 and its auxiliary facilities.

In FIG. 1, reference numeral 50 denotes a cyclone, 90 denotes a wet vibration damper, and 45 denotes a molten combustion apparatus.

The preliminary reduction process can be classified into moving bed and fluidized bed according to the contact state of iron ore with reducing gas. Iron ore with a wide particle size distribution is charged into the preliminary reduction reactor and the reducing gas is sent through the distribution plate at the bottom to reduce iron ore while flowing. A fluidized bed equation is known as a suitable way to reduce such iron ore.

In order to effectively reduce the iron ore having such a large particle size distribution and to charge the molten reduction reactor, it has been mainly used to pass through a plurality of conical fluidized bed preliminary reactors. However, through the multiple fluidized bed preliminary reactors, iron ore is generated and accumulated a lot of differentiation due to differentiation, thereby increasing the load on the cyclone, a gas purification facility for each fluidized bed preliminary reactor, and thus reducing to the next fluidized reactor. By increasing the dust content of the gas, fine powder is attached to the distribution plate of the preliminary reactor, which eventually blocks the holes of the distribution plate, which not only prevents the flow of iron ore in the preliminary reactor, but also causes clogging in extreme cases due to excessive micronization of the cyclone. This will cause huge disruption to the operation.

Examples of methods for solving the above problems include US Patent No. 4,978,387, Korean Patent Application No. 87-12076, and Japanese Patent Laid-Open No. 62-224620. In these methods, differential reduction ore is finally preliminarily reduced. What is collected from the cyclone of the furnace is fed to the melting reduction furnace to process the fine powder.

However, in the above methods, the differential reduction ore collected in the cyclone of the final preliminary reduction furnace is blown into the molten reduction furnace, and the differentiation of the iron ore is almost completed in the first preliminary reduction furnace in which the iron ore is directly charged. It has been found that the differential dust collection burden of the cyclone in the reduction furnace is increased.

That is, in the above methods, the fine powder is rapidly increased due to the differentiation of iron ore, which is almost completed in the first preliminary reduction reactor, and thus, the burden of the first preliminary reduction reactor cyclone is increased, and the efficiency is lowered, and even clogging in severe cases. There is a problem that occurs.

The present inventors have filed a Korean Patent Application No. 97-71432 by proposing a fluidized bed type preliminary reduction device for iron ore and a method for preliminary reduction of iron ore using the same.

However, the above-described patent application No. 97-71432 has not solved problems such as weighting of the cyclone caused by particulate ore generated in the final preliminary reduction furnace and reducing its efficiency.

The present invention is an improvement of the Republic of Korea Patent Application No. 97-71432, a differential flow reduction reactor for separately preliminary reduction only the fines generated in the cyclone that is generated in the preliminary reduction reactor and configured to process the fine powder scattered with the exhaust gas, respectively. The purpose of the present invention is to reduce the dusting load of the cyclone, to prevent clogging occurring in extreme cases, and to reduce the scattering loss of the iron ore by minimizing the fine powder content in the exhaust gas.

1 is an example configuration of a conventional fluidized bed pre-reduction reactor

Figure 2 is an example configuration of the fluidized bed pre-reduction device of the ferrite ore according to the present invention

Explanation of symbols on the main parts of the drawings

110 ... melt gasification furnace 120 ... final preliminary reduction reactor

130 ... first reserve reduction furnace 140 ... differential flow reduction reactor

150 ... First Cyclone 160 ... Second Cyclone

170 ... Third Cyclone 180 ... Wet Vibrator

165,114,116 ... Reduced gas supply pipe 121 ... Reduced iron discharge pipe

115,117 ... Flow regulating valve 152,153,163,164 ...

151,162 ... first and second anisotropy

The present invention comprises a plurality of pre-reduction furnace configured to reduce the iron ore while forming a bubble flow layer; And

In the fluidized bed pre-reduction device of the iron-iron ore comprising a plurality of cyclones for collecting particulate ore contained in each exhaust gas of the pre-reduction path,

A powder flow reduction reactor configured to receive and reduce particulate ore collected in each cyclone;

And a third cyclone for collecting particulate ore contained in the flue gas of the finely divided flow reduction reactor.

The present invention also relates to a method for preliminary reducing iron ore using the fluidized bed preliminary reduction apparatus of the iron ore of the present invention described above.

Hereinafter, the present invention will be described in detail with reference to the drawings.

Figure 2 shows an example of a fluidized bed pre-reduction device of the iron ore of the present invention.

As shown in FIG. 2, the fluidized bed preliminary reduction apparatus 100 of the iron ore of the present invention is configured to receive the iron ore from the hopper for storing the iron ore (not shown) and form a bubble fluidized bed to reduce the first fluid ore. Preliminary reduction path 130;

A final preliminary reduction path 120 configured to receive the preliminary reduction ore discharged from the first preliminary reduction path 130 and finally reduce and discharge the preliminary reduction ore;

A first cyclone 150 for collecting particulate ore contained in the exhaust gas of the first preliminary reduction reactor 130;

A second cyclone 160 for collecting particulate ore contained in the exhaust gas of the final preliminary reduction reactor 120;

A differential flow reduction reactor 140 configured to receive and reduce the fine ore collected in the first cyclone 150 and the second cyclone 160;

And a third cyclone 170 for collecting particulate ore contained in the flue gas of the finely divided flow reduction reactor 140.

The first preliminary reduction path 130 has a conical structure, the first gas distribution plate 137 is mounted therein, the bottom of the first gas distribution plate 137 is used as a reducing gas for the final preliminary reduction The first reduction gas supply pipe 165 for supplying the flue gas of the furnace 120 and the flue gas of the fine oil flow reduction reactor 140 is connected, and the side wall of the first gas distribution plate 137 is connected to a raw material charging hopper. The ore supply pipe 133 for supplying the prepared preparations, such as stored iron ore and limestone into the reduction furnace, and the pre-reduced ore discharge pipe 131 for discharging the pre-reduced ore are connected.

In addition, an upper portion of the first preliminary reduction path 130 is connected to the first cyclone 150 through a first exhaust gas discharge pipe 132.

The first particulate light supply pipe 153 for supplying the fine ore contained in the exhaust gas of the first preliminary reduction path 130 to the first preliminary reduction path 130 at the lower portion of the first high temperature cyclone (150) Is connected, preferably, it is extended to the bottom in the first preliminary reduction path 130.

The first cyclone is connected to a second exhaust gas discharge pipe 154 for discharging the exhaust gas of the first preliminary reduction path 130 from which the fine ore is separated, and the second exhaust gas discharge pipe 154 is a wet vibration suppressor 180. In communication with

The first particulate light supply pipe 153 is connected to the second particulate light supply pipe 152 for supplying the fine ore to the differential flow reduction path 140, the first particulate light supply pipe 153 and the second particulate The first anisotropic side 151 is provided at the connection portion of the light supply pipe 152.

The final preliminary reduction path 120 has a conical structure, the second gas distribution plate 127 is mounted therein, and the second reduction gas supply pipe 114 for supplying reducing gas is connected to the bottom thereof. The side walls of the second gas distribution plate 127 have a pre-reduced light discharge pipe 131 for supplying pre-reduced ore pre-reduced ore from the first pre-reduction path 130 and for discharging the final reduced ore. Reduced iron discharge pipe 121 is connected.

In addition, an upper portion of the final preliminary reduction path 120 is connected to the second cyclone 160 through a third exhaust gas discharge pipe 122.

A third particulate light supply pipe 163 is connected to a lower portion of the second cyclone 160 to supply particulate ore contained in exhaust gas of the final preliminary reduction path 120 to the final preliminary reduction path 120. Preferably, it extends to the bottom in the final preliminary reduction path (120).

The third particulate light supply pipe 163 is connected to the fourth particulate light supply pipe 164 for supplying the particulate ore to the differential flow reduction path 140, the fourth particulate light supply pipe 164 is the fine flow flow It is desirable to extend to the bottom in the reduction furnace 140.

A second anisotropic side 162 is provided at a connection portion of the third particulate light supply pipe 163 and the fourth particulate light supply pipe 164.

A first reducing gas supply pipe 165 is connected to the second high temperature cyclone 160 to use exhaust gas separated from particulates as a reducing gas, and the first reducing gas supply pipe 165 is a first preliminary reduction path. It is in communication with the bottom of 130.

The differential flow reduction path 140 has a cylindrical structure, and a third gas distribution plate 147 is mounted therein, and a third reducing gas supply pipe 116 for supplying a reducing gas is connected to a bottom thereof. have.

As shown in FIG. 2, when the preliminary reduction apparatus of the present invention is connected to the molten gasifier 110, the second reducing gas supply pipe 114 and the third reducing gas supply pipe 116 are the molten gasifier 110. In order to use the exhaust gas of the reducing gas is preferably configured to be in communication with the melting gasifier (110).

In addition, the fine particle discharge pipe 141 for discharging the reduced fine ore is connected to the side wall of the differential flow reduction path 140, and the second fine particle to receive the fine ore collected from the first cyclone (150) The light supply pipe 152 is connected.

In addition, an upper portion of the differential flow reduction path 140 is connected to the third cyclone 170 through a fourth exhaust gas discharge pipe 145.

A fifth particulate light supply pipe 171 is connected to a lower portion of the third cyclone 170 to supply the particulate ore contained in the flue gas of the powder flow reduction reactor 140 to the powder flow reduction reactor 140. .

The fifth exhaust gas discharge pipe 172 for discharging the exhaust gas separated from the particulate light is connected to the upper portion of the third cyclone 170, the fifth exhaust gas discharge pipe 172 is the first reducing gas supply pipe 165 In communication with

On the other hand, the second reducing gas supply pipe 114 and the third reduction gas supply pipe 116 is preferably provided with first and second flow control valves 115 and 117, respectively.

As shown in FIG. 2, when the melt gasifier 110 is provided, the second reduced gas supply pipe 114 and the third reducing gas supply pipe 116 are connected to the upper portion of the melt gasifier 110 to melt the gasification. In communication with the sixth exhaust gas supply pipe 113 for discharging the exhaust gas of the furnace 110, and the reduced iron discharge pipe 121 is also connected to the molten gasifier 110 in the ore communication relationship.

In addition, the particulate light discharge pipe 141 is connected to the melting and combustion device 142.

Meanwhile, the first reducing gas supply pipe 165, the second reducing gas supply pipe 114, and the third reducing gas supply pipe 116 may be supplied with oxygen (O ₂ ).

In Fig. 2, reference numeral 111 denotes "melting line" and 112 denotes "coal layer".

Hereinafter, a method of preliminarily reducing the iron ore using the fluidized bed preliminary reduction apparatus of the iron ore will be described.

The iron ore is charged into the first preliminary reduction reactor 130 and uses the exhaust gas of the final preliminary reduction reactor 120 and the differential flow reduction reactor 140 as the reducing gas.

In this case, when the first preliminary reduction reactor 130 does not reach the target temperature by the exhaust gas of the final preliminary reduction reactor 120 and the exhaust gas of the differential flow reduction reactor 140, oxygen is blown to raise the reducing gas to raise the first preliminary gas. The temperature in the reduction furnace 130 is adjusted.

In the conical first preliminary reduction path 130, not only iron ore is pre-reduced by the preliminary reduction gas coming through the first reducing gas supply pipe 165, but also differentiation of iron ore occurs due to reduction, so the fine content increases rapidly. Such a large amount of fine powder is collected in the first cyclone 150 to purify the exhaust gas of the first preliminary reduction path 130, the initial operation of the first anisotropic 151 in the direction of the first preliminary reduction path 130 Opening and recycling, but when the charging and discharge of iron ore is in a steady state while maintaining a constant fluidized bed height, the first anisotropic 151 is opened toward the differential flow reduction path 140 to the differential flow reduction path (140). To reduce the burden on the first cyclone (150) by treating the fine reduced ore generated in the first preliminary reduction path 130 and accumulating with the continuous charging of iron ore without recycling. Let's do it.

Exhaust gas of the first preliminary reduction path 130 from which the fine ore is separated from the first cyclone 150 is scrubbed by the wet dust eliminator 180 to remove dust and is discharged to the outside.

Meanwhile, the pre-reduced coarse iron ore that is not scattered in the first preliminary reduction path 130 is charged into the final preliminary reduction path 120 through the preliminary reduction ore discharge pipe 131 and finally reduced.

The preliminary reduction iron ore charged into the final preliminary reduction reactor 120 is the final preliminary reduction by the exhaust gas of the melt gasifier 110 introduced for use as reducing gas through the second reduction gas supply pipe 114, the molten gasification furnace If the reducing gas coming from 110 does not reach the target temperature of the final preliminary reduction reactor 120, the oxygen is blown to raise the reducing gas to adjust the temperature in the final preliminary reduction reactor 120.

Particulate ore contained in the exhaust gas discharged from the final preliminary reduction path 120 is collected in the second cyclone 160 to open the second anisotropy 162 toward the final preliminary return path 120 at the beginning of the operation. Ring, but when the charging and discharging of the final preliminary reduction reactor 120 and the steady state of the fluidized bed are reached, the second anisotropic side 162 is opened toward the differential flow reduction reactor 140 to finely reduce the finely-reduced iron. It is charged to the flow reduction path 140.

As such, by not recycling the fine iron into the final preliminary reactor 120, the fine collection capacity of the second cyclone 160 can be improved to effectively remove fine powder in the reducing flue gas.

Then, the coarse reducing ore that is not scattered in the final preliminary reduction reactor 120 is discharged and charged into the melt gasifier 110 is melt-reduced to be manufactured as molten iron.

The unspectral spectra collected in the first cyclone 150 and the second cyclone 160 and charged in the differential flow reduction reactor 140 are melted introduced for use as the reducing gas through the third reducing gas supply pipe 116. The final preliminary reduction by the exhaust gas of the gasifier 110, if the reducing gas coming from the molten gasifier 110 does not reach the target temperature of the final preliminary reduction reactor 120, the oxygen is blown to raise the reducing gas to the differential flow The temperature in the reduction furnace 140 is adjusted.

The fine powder contained in the gas discharged from the differential flow reduction path 140 is collected in the third cyclone 170 attached to the differential flow reduction path 140 and recycled to the differential flow reduction path 140. The finely-reduced iron discharged from the flow reduction path 140 is blown into the molten gasifier 110 by oxygen by the melting and combustion device 142, and is finally reduced while being melted and dropped as it is without being scattered in the molten gasifier 110.

Exhaust gas (reduction gas) discharged from the melt gas furnace 110 is distributed to the second preliminary reduction path 120 and the differential flow reduction path 140, the flow rate of the flow control valve 115, 117, respectively Can be adjusted by

As described above, in the present invention, the first and second anisotropy in the steady state where the loading and discharge of the conical final preliminary reduction path 120 and the conical first preliminary reduction path 130 and the height of the fluidized bed is constant, the differential flow reduction By opening in the furnace 140 to effectively process the fine powder, the fine dust collecting ability of the first and second cyclones (150, 160) can be sufficiently exhibited to significantly reduce the dust content of the exhaust gas.

2 shows only a fluidized bed preliminary reduction device of two-stage iron ore, the present invention is not limited to the two-stage preliminary reduction device, and may be applied to a multistage preliminary reduction device such as a three-stage preliminary reduction device. It is.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example

Reduction experiments were performed under the following conditions using the reduction apparatus of FIG. 2 having the following size, and the dust content and the scattering rate of the exhaust gas were measured, and the results are shown in Table 1 below.

1) Specification and condition of reduction device

end. Conical final and first preliminary reduction reactor

Reduction part (distribution plate) inner diameter: 0.3m

Enlarged part inner diameter: 0.7m

Cone Bottom Angle: 4 degrees

-Height of the inclined part (on the surface of the dispersion plate): 4.0m

Cylindrical Upper Height: 2.5m

Flow rate: 1.2 m / s

Pressure: 1.8kgf / ㎠ (conical first preliminary reduction reactor), 2.0kgf / ㎠ (conical final reserve reduction reactor)

I. Differential Flow Reduction Furnace

Inner diameter: 0.25m

Height (at the surface of the dispersion plate): 2 m

Flow rate: 0.2 m / s

Pressure: 2.0kgf / ㎠

All. Raw material

A. Iron ore (-8mm)

-Chemical composition: T.Fe: 62.17%, FeO: 0.51%, SiO ₂ : 5.5%, TiO ₂ : 0.11%,

Mn: 0.05%, S: 0.012%, P: 0.65%, Number of crystals: 2.32%

Particle size distribution: -0.05mm: 4.6%, 0.05-0.15mm: 5.4%, 0.15-0.5 mm: 16.8%,

0.5-4.75mm: 59.4%, 4.75-8mm: 13.8%

N. gas

-Chemical composition: CO: 65%, H ₂ : 25%, CO ₂ : 5%, N ₂ : 5%

Gas temperature: final preliminary reduction and differential flow reduction reactor: 850 ℃, first preliminary reduction reactor: 780 ℃

Experimental condition Flue gas dust content (g / N㎥) % Scattering Experiment 1 Undiluted oil flow reduction reactor 2.5 0.41 Experiment 2 Via a differential flow reduction reactor 0.7 0.11

As a result of the experiment under the experimental conditions, it was found that the dust content of the exhaust gas is greatly reduced by using a fine fluidized bed reduction furnace, which can greatly reduce the scattering loss of iron ore. At this time, the gas utilization rate is about 30-35%, the gas source unit is 1300-1500N㎥ / ton-ore, and the reduction rate of iron ore discharged from the first conical preliminary reduction reactor and entering the conical final preliminary reduction reactor is 30-40%, and the final The reduction rate of the reduced iron charged into the melt gasifier in the preliminary reduction furnace is 80-85%, while the reduction rate of the finely divided iron discharged from the cylindrical fine flow reduction reactor is high up to about 90%, making it easier to reduce the fine spectroscopy. Could.

As described above, the present invention connects the microfluidic flow reduction path with the cyclone of the preliminary reduction path in which iron ore differentiation occurs, and separates the fine particles from the coarse ore, thereby reducing the burden of micron processing due to recycling. The fine powder removal ability in the flue gas is improved, and thus, the fine powder content in the flue gas is greatly reduced.

Claims (6)

A first preliminary reduction path 130 configured to receive the ferrous iron ore from the iron ore storage hopper and form a bubble fluidized bed to reduce the iron ore; A final preliminary reduction path 120 configured to receive the preliminary reduction ore discharged from the first preliminary reduction path 130 and finally reduce and discharge the preliminary reduction ore; A first cyclone 150 for collecting particulate ore contained in the exhaust gas of the first preliminary reduction reactor 130; and It includes a second cyclone 160 for collecting the fine ore contained in the exhaust gas of the final preliminary reduction path 120, The first gas distribution plate 137 is mounted in the first preliminary reduction path 130, and the bottom of the exhaust gas and the differential flow reduction path 140 of the final preliminary reduction path 120 used as the reducing gas is installed at the bottom thereof. The first reducing gas supply pipe 165 for supplying the exhaust gas is connected, the side wall of the upper portion of the first gas distribution plate 137 for supplying preparation materials such as iron ore and limestone stored in the raw material loading hopper into the reduction furnace. The ore supply pipe 133 and the pre-reduced ore discharge pipe 131 for discharging the pre-reduced ore is connected, the upper portion of the first pre-reduction path 130 is connected between the first through the first exhaust gas discharge pipe 132 Connected to cron 150; A second gas distribution plate 127 is mounted in the final preliminary reduction path 120, and a second reduction gas supply pipe 114 for supplying a reducing gas is connected to a bottom thereof, and the second gas dispersion is performed. The side wall of the upper plate 127 is connected to a pre-reduced light discharge pipe 131 for supplying a pre-reduced ore pre-reduced in the first pre-reduction path 130 and a reduced iron discharge pipe 121 for discharging the final reduced ore In the above, the upper portion of the final preliminary reduction path 120 is connected to the second cyclone 160 through the third exhaust gas discharge pipe 122 in the fluidized bed pre-reduction device of the iron ore, A differential flow reduction reactor 140 configured to receive and reduce the fine ore collected in the first cyclone 150 and the second cyclone 160; And further comprises a 3 cyclone (170) for collecting the fine ore contained in the flue gas of the powder flow reduction reactor 140, A first particulate light supply pipe 153 is connected to a lower portion of the first cyclone 150 to supply the fine ore contained in the exhaust gas of the first preliminary reduction path 130 to the first preliminary reduction path 130. The first particulate light supply pipe 153 is connected to the second particulate light supply pipe 152 for supplying particulate ore to the differential flow reduction path 140, and is connected to the first particulate light supply pipe 153. A first anisotropic side 151 is provided at the connection portion of the second particulate light supply pipe 152, and the second cyclone 150 has a second exhaust gas discharge pipe 154 for discharging the exhaust gas from which fine powder is separated. ) Is connected, and the second exhaust gas discharge pipe 154 is in communication with the wet oscillator 180; A third particulate light supply pipe 163 is connected to a lower portion of the second cyclone 160 to supply the fine ore contained in the exhaust gas of the final preliminary reduction path 120 to the final preliminary reduction path 120. The third particulate light supply pipe 163 is connected to the fourth particulate light supply pipe 164 for supplying particulate ore to the differential flow reduction path 140, and the third particulate light supply pipe 163 and the fourth particulate light are connected to the third particulate light supply pipe 163. The second anisotropic side 162 is provided at the connection portion of the supply pipe 164. A first reducing gas supply pipe 165 is connected to an upper portion of the second cyclone 160; The differential flow reduction path 140 has a cylindrical structure, and a third gas distribution plate 147 is mounted therein, and a third reducing gas supply pipe 116 for supplying a reducing gas is connected to a bottom thereof. A particulate light discharge pipe 141 for discharging the reduced particulate ore is connected to a sidewall of an upper portion of the third gas dispersion plate 147; The upper portion of the differential flow reduction path 140 is connected to the third cyclone 170 through a fourth exhaust gas discharge pipe 145, and the differential flow reduction path 140 is located below the third cyclone 170. The fifth particulate light supply pipe 171 for supplying the fine ore contained in the exhaust gas of the) to the differential flow reduction path 140 is connected, A fifth exhaust gas discharge pipe 172 for discharging the exhaust gas separated from the particulate light is connected to an upper portion of the third cyclone 170, and the fifth exhaust gas discharge pipe 172 is connected to the first reducing gas supply pipe 165. Fluidized bed pre-reduction device of iron ore characterized in that the communication is configured The method of claim 1, wherein the second reducing gas supply pipe 114 and the third reducing gas supply pipe 116, the first or second flow control valves 115 and 117, respectively, characterized in that the iron ore Fluidized bed pre-reduction device According to claim 1 or 2, wherein the first particulate light supply pipe 153 and the third particulate light supply pipe 163 are extended to the lower portion in the first preliminary reduction path 130 and the final preliminary reduction path 120, respectively. Fluidized bed pre-reduction device of iron ore characterized in that In preliminary reduction of the iron ore using the fluidized bed preliminary reduction device of the iron ore of claim 1, the iron ore charged in the first preliminary reduction path 130 is exhaust gas of the final preliminary reduction path 120 supplied from the bottom and The primary preliminary reduction by the exhaust gas of the differential flow reduction reactor 140, the differential reduction ore collected in the first cyclone 150 is recycled to the first preliminary reduction reactor 130 at the beginning of the operation, the first preliminary reduction reactor At 130, when the charging and discharging of the iron ore reaches a steady state in which the height of the fluidized bed becomes constant, the first anisotropic side 151 is opened toward the differential flow reduction path 140 so that the differential reduction ore flows into the differential flow reduction path 140 Charge); The first preliminary reduction in the first preliminary reduction path 130 and charged to the final preliminary reduction path 120 is finally pre-reduced by the reducing gas supplied from the bottom discharged, collected in the second cyclone 160 The differential reduction ore is recycled to the final preliminary reduction reactor 120 at the beginning of the operation, and when the charging and discharging of the ferrite ore and the height of the fluidized bed are reached in the final preliminary reduction reactor 130, the second anisotropy ( 162) to open toward the differential flow reduction path 140 so that the differential reduction ore is charged into the differential flow reduction path 140; And The differential reduction ore collected in the first cyclone 150 and the second cyclone 160 and charged in the differential flow reduction reactor 140 may be finally reduced and discharged by the reducing gas supplied from the bottom. Preliminary reduction method of iron ore 5. The method for preliminary reduction of iron ore according to claim 4, wherein the first and second anisotropies 151 and 162 are interlocked to open and close so that finely-reduced iron is blown into the molten gasifier. The method of claim 4 or 5, wherein the differential reduction ore discharged from the differential flow reduction path 140 is blown into the melt gasifier 110 by the melting and combustion device 142, and the final preliminary reduction path 120 Preliminary reduction method of the iron ore, characterized in that to be charged into the molten gasifier 110 discharged from the granulated reduction ore discharged from