KR102046494B1 - Apparatus for refining reducing gas and apparatus for manufacturing molten iron comprising the same - Google Patents

Abstract

Provided is a reduction gas purification method for removing and separating carbon dioxide in a reducing gas, a reduction gas purification device, and an apparatus for manufacturing molten iron including the same. Reduction gas purifying method according to an embodiment of the present invention, the reduction furnace in the molten iron manufacturing apparatus comprising: i) a melt gasification furnace in which reduced iron is charged, and ii) a reduction furnace for reducing iron ore to provide reduced iron to the melt gasifier. Purify the reducing gas discharged from. Reducing gas purification method according to an embodiment of the present invention, i) providing ammonia gas, ii) mixing ammonia gas with a reducing gas to provide a mixed gas, iii) cooling the mixed gas to 50 ℃ or less Purifying the reducing gas by removing carbon dioxide contained in the mixed gas while producing ammonium carbonate, iv) supplying the purified reducing gas to the reduction furnace, v) liquefying ammonium carbonate salt, vi) liquefied ammonium carbonate salt Pyrolysing carbon dioxide and ammonia, and vii) washing the ammonia to provide ammonia water. In the step of providing ammonia gas, the ammonia gas is provided by heating the ammonia water.

Description

Reducing gas purifying apparatus and molten iron manufacturing apparatus including the same {APPARATUS FOR REFINING REDUCING GAS AND APPARATUS FOR MANUFACTURING MOLTEN IRON COMPRISING THE SAME}

The present invention relates to a reducing gas purification apparatus and a molten iron manufacturing apparatus including the same. More specifically, the present invention relates to a reducing gas purification apparatus for removing and separating carbon dioxide in a reducing gas and a molten iron manufacturing apparatus including the same.

In the molten iron reduction method, a reduction furnace for reducing iron ore and a melt gasification furnace for melting reduced iron ore are used. As a heat source for melting the reduced iron charged into the melt gasifier, coal briquettes obtained by agglomeration of coal are charged into the melt gasifier. The reducing gas generated in the melt gasifier is supplied to the reduction furnace to reduce the iron ore charged in the reduction furnace and then discharged from the reduction furnace.

Since the discharged reducing gas contains a large amount of carbon monoxide, hydrogen, and methane having a reducing power, not only can the fuel cost be reduced when reused in the reduction furnace, but also the carbon dioxide generation can be greatly reduced. However, since the exhaust gas contains about 30% of carbon dioxide, side effects such as calorie loss, carbon dioxide accumulation, and equipment overload occur when this is directly injected into the reduction furnace.

It is to provide a reducing gas purification method for removing and separating carbon dioxide. It is an object of the present invention to provide a reducing gas purification apparatus for carrying out the above-described reducing gas purification method. The present invention provides a molten iron manufacturing apparatus including the reducing gas refining apparatus.

Reduction gas purifying method according to an embodiment of the present invention, the reduction furnace in the molten iron manufacturing apparatus comprising: i) a melt gasification furnace in which reduced iron is charged, and ii) a reduction furnace for reducing iron ore to provide reduced iron to the melt gasifier. Purify the reducing gas discharged from. Reducing gas purification method according to an embodiment of the present invention, i) providing ammonia gas, ii) mixing ammonia gas with a reducing gas to provide a mixed gas, iii) cooling the mixed gas to 50 ℃ or less Purifying the reducing gas by removing carbon dioxide contained in the mixed gas while producing ammonium carbonate, iv) supplying the purified reducing gas to the reduction furnace, v) liquefying ammonium carbonate salt, vi) liquefied ammonium carbonate salt Pyrolysing carbon dioxide and ammonia, and vii) washing the ammonia to provide ammonia water. In the step of providing ammonia gas, the ammonia gas is provided by heating the ammonia water.

The step of liquefying ammonium carbonate salt may be achieved by adding steam to the ammonium carbonate salt. In the step of providing the mixed gas, the molar ratio of carbon dioxide, ammonia gas, and moisture contained in the reducing gas is supplied with moisture and ammonia gas may be the same.

  Reducing gas purification apparatus according to an embodiment of the present invention, i) a gas mixer receiving a reducing gas from the reduction furnace and mixed with ammonia gas to provide a mixed gas, ii) receiving a mixed gas to cool the mixed gas to carbonic acid A gas cooler that removes carbon dioxide contained in the mixed gas while producing an ammonium salt to provide a purified reducing gas; Ammonium carbonate decomposer, and iv) an ammonia heater that heats ammonia water to produce ammonia gas and provide it to the gas mixer.

The gas mixer and the gas cooler may be formed as an integrated module. The integrated module includes: i) a body part, ii) a body part, a reducing gas injection hole into which a reducing gas is introduced, a guide part whose cross-sectional area gradually increases toward the body part, iii) a body part, A porous plate having openings formed therein, iv) a fin tube which surrounds the inside of the body portion and indirectly cools the reducing gas injected through the plurality of openings while the cooling water is supplied and circulates to produce ammonium carbonate salt on the surface thereof; Connected, it may include a reducing gas discharge unit for discharging the purified reducing gas to the outside. The guide part may further include a steam inlet for liquefying ammonium carbonate salt by irradiating steam to the fin tube. The integrated module may further include a guide vane formed around the reducing gas inlet while forming an acute angle with the surface of the guide part in the guide part, and the cross-sectional area thereof gradually widening toward the body part.

The apparatus for manufacturing molten iron according to an embodiment of the present invention includes: i) a reduction furnace in which iron ore is charged and a reducing gas is supplied; ii) a reduction gas purification apparatus connected to a reduction furnace, and iii) a reduction gas purification apparatus and a reduction furnace. It is connected to supply a reducing gas to the reduction furnace, and includes a molten gasifier in which the reduced iron in which the iron ore is reduced in the charging furnace is charged. The reduction furnace may be a fluidized bed reduction furnace or a packed bed reduction furnace.

Ammonium carbonate can be produced to selectively remove carbon dioxide contained in the reducing gas. As a result, it is possible to minimize the reducing power loss of the exhaust gas and to re-introduce the exhaust gas into the reduction furnace.

1 is a schematic flowchart of a reducing gas purification method according to an embodiment of the present invention.
2 is a schematic view of a reducing gas purification apparatus according to an embodiment of the present invention.
3 is a schematic perspective view of an integrated module included in the reducing gas purification apparatus of FIG. 2.
4 is a schematic cross-sectional view of the integrated module taken along line IV-IV of FIG. 3.
FIG. 5 is a schematic view of a molten iron manufacturing apparatus including the reducing gas purification apparatus of FIG. 2.
FIG. 6 is a schematic view of another apparatus for manufacturing molten iron including the reducing gas purifying apparatus of FIG. 2.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” include plural forms as well, unless the phrases clearly indicate the opposite. As used herein, the meaning of "comprising" embodies a particular property, region, integer, step, operation, element, and / or component, and other specific properties, region, integer, step, operation, element, component, and / or group. It does not exclude the presence or addition of.

Unless defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Commonly defined terms used are additionally interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

1 is a schematic flowchart of a reducing gas purification method according to an embodiment of the present invention. These flowcharts are merely illustrative of the present invention and are not limited to the present invention.

As shown in FIG. 1, the refining gas purification method includes providing ammonia gas (S10), mixing ammonia gas with a reducing gas to provide a mixed gas (S20), and cooling the mixed gas to form ammonium carbonate salt. Removing the carbon dioxide while producing (S30), supplying the purified reducing gas to the reduction furnace (S40), liquefying the ammonium carbonate salt (S50), pyrolyzing the liquefied ammonium carbonate salt with carbon dioxide and ammonia (S60) ), To wash the ammonia to provide ammonia water (S70), and to heat the ammonia water (S80). In addition, the purification method of the reducing gas may further include other steps.

In step S10, ammonia gas is provided. Ammonia gas is provided by heating ammonia water in step S80. In this case, it is preferable to heat ammonia water to 50 degreeC-100 degreeC. Heating the ammonia water to too high a temperature may cause the ammonia water to evaporate with the water, resulting in a low concentration of ammonia gas. In addition, heating to too low a temperature makes it difficult to obtain a desired amount of ammonia gas. Therefore, ammonia water is heated to the above-mentioned temperature range.

In step S20, ammonia gas is mixed with a reducing gas. Both are gaseous, so they mix well and uniformly. Here, ammonia gas is used to remove carbon dioxide contained in the reducing gas. It is necessary to adjust the input amount of ammonia gas according to the composition of the reducing gas. And since the production efficiency of the ammonium carbonate salt varies according to the water content of the reducing gas, it is possible to selectively add water according to the composition of the reducing gas. However, when ammonia gas and water are added more than necessary amount, an appropriate amount is required because the process cost may increase and the thermal efficiency of the reduction furnace may be lowered. For example, the molar ratios of carbon dioxide, ammonia gas, and water contained in the reducing gas can be the same.

Next, in step S30, carbon dioxide is removed while cooling the mixed gas to produce ammonium carbonate. This is represented by the following formula (1). That is, when the mixed gas is cooled to 50 ° C. or less, as the forward reaction proceeds, carbon dioxide, ammonia gas, and water react with each other to form ammonium carbonate. If the cooling temperature of the mixed gas is too large, it is difficult to remove carbon dioxide because the forward reaction does not proceed well as shown in the following formula (1). Therefore, carbon dioxide can be easily removed by cooling the mixed gas below the aforementioned temperature.

[Formula 1]

CO ₂ + NH ₃ + H ₂ O → NH ₄ HCO ₃

Here, the cooling of the mixed gas is made by indirect contact with the cooling water. When the mixed gas is cooled in direct contact with the refrigerant, loss of reducing gas may occur and carbon dioxide removal efficiency may decrease. Therefore, it is desirable to form ammonium carbonate through indirect cooling to selectively remove carbon dioxide.

In step S40, the purified reducing gas is supplied to a reduction furnace. Since the temperature of the reducing gas is low, it is possible to heat the reducing gas by heating with an oxygen burner or the like and then supply it to the reduction furnace again. Since the reducing power of the reducing gas is restored through these steps, it is possible to reduce the amount of reducing gas used in the reducing furnace to improve fuel costs. Steps S50 to S80 described below are separate processes from the purification of the reducing gas, and are processes for treating the ammonium carbonate salt generated during the purification of the reducing gas.

First, in step S50, ammonium carbonate is liquefied. The ammonium carbonate salt may be irradiated with steam at 100 ° C. to 140 ° C. to convert the solid ammonium carbonate salt into a liquid state. Preferably, the temperature of the steam may be 120 ° C. When using low temperature steam, the liquefaction efficiency of ammonium carbonate salt falls. In addition, when using high-temperature steam, the amount of use can be reduced and the liquefaction time of the ammonium carbonate salt can be shortened, but the equipment cost is increased because a facility that can withstand high temperature and high pressure is required. In particular, a reactor in which solid ammonium carbonate is produced is difficult to manufacture such that a cooling tube in the form of a fin tube has a high pressure therein. Therefore, the temperature of steam is adjusted to the above-mentioned range.

Next, in step S60, the liquefied ammonium carbonate salt is thermally decomposed into carbon dioxide and ammonia. That is, the liquid ammonium carbonate is further heated to thermally decompose it into carbon dioxide and ammonia. This process corresponds to the inverse reaction in Formula 1 above. That is, by continuously irradiating steam at 70 ℃ to 100 ℃ pyrolysis of ammonium carbonate salts with carbon dioxide and ammonia. In addition, among other impurities, for example, an acid gas such as hydrogen sulfide may be separated from carbon dioxide using an organic solvent such as methyl-diethanolamine. Carbon dioxide can be released into the atmosphere, so it can be released or recycled out of the process.

In step S70, ammonia is washed to provide ammonia water. The ammonia can be purified in the scrubber tower. That is, ammonia water is produced while water is mixed with ammonia.

Finally, in step S80, ammonia water is heated. Therefore, water is separated from ammonia to produce ammonia gas. Ammonia gas is used again in step S10.

Figure 2 schematically shows a reducing gas purification apparatus 100 according to an embodiment of the present invention. The structure of the reducing gas purification apparatus 100 shown by the dotted line in FIG. 2 is merely for illustrating the present invention, and the present invention is not limited thereto. Therefore, the structure of the reducing gas purification apparatus 100 may be modified in other forms. In addition, each device and the reduction furnace included in the reducing gas purification apparatus 100 are shown in blocks for convenience of explanation. In FIG. 2, the flow of gas is indicated by a solid arrow, and the flow of liquid is indicated by a dotted arrow.

As shown in FIG. 2, the reducing gas purification apparatus 100 includes a gas mixer 10, a gas cooler 12, an ammonium carbonate cracker 14, and an ammonia heater 16. In addition, the reducing gas purification apparatus 100 may further include other devices as necessary.

The gas mixer 10 receives a reducing gas from the reduction furnace 21. Here, the reduction furnace 21 corresponds to the fluidized-bed reduction reactor 20 of FIG. 4 and the packed-bed reduction reactor 67 of FIG. 5. The gas mixer 10 is also supplied with ammonia gas and moisture. Therefore, a reducing gas, ammonia gas and moisture are mixed to prepare a mixed gas. The mixed gas is supplied to the gas cooler 12. The gas cooler 12 cools the mixed gas to produce ammonium carbonate salt. The gas cooler 12 removes carbon dioxide contained in the mixed gas to provide a purified reducing gas. The purified reducing gas is supplied to the reduction furnace 20.

On the other hand, the ammonium carbonate salt cracker 14 receives ammonium carbonate salt from the gas cooler 12. The ammonium carbonate salt cracker 14 decomposes the ammonium carbonate salt into a carbon dioxide and ammonia solution. Carbon dioxide is emitted out of the system. The ammonia heater 16 receives the ammonia solution and heats it to supply ammonia gas and moisture to the gas mixer 10. If the reducing gas discharged from the reduction furnace 21 contains a sufficient amount of water, the ammonia heater 16 does not need to supply water to the gas mixer 10. On the other hand, the water produced by the ammonia heater 16 is discharged out of the system.

The above-described methods can be used to remove carbon dioxide contained in the reducing gas. As a result, the reducing gas having improved reducing power can be reused in the reducing furnace, thereby significantly reducing the fuel cost.

3 shows a perspective view of the integrated module 11 included in the reducing gas purification apparatus of FIG. 2. The structure of the reducing gas purification module 11 of FIG. 3 is merely for illustrating the present invention, and the present invention is not limited thereto. Therefore, the structure of the reducing gas purification module 11 may be modified in other forms.

In the integrated module 11 shown in FIG. 3, a gas mixer 10 (shown in FIG. 2) and a gas cooler 12 (shown in FIG. 2) are integrally formed. Since the gas mixer 10 and the gas cooler 12 are integrally formed, the facility cost can be reduced by simplifying the facility.

The integrated module 11 includes a body 111, a guide 113, a steam inlet 1115, a reducing gas inlet 1113, an ammonia gas inlet 1133 and a reducing gas outlet 1151. In addition, the integrated module 11 may further include other components as necessary. The reducing gas introduced through the reducing gas injection hole 1131 formed in the guide part 113 is purified by removing carbon dioxide from the mixed gas generated by mixing with the ammonia gas. The purified reducing gas is discharged to the outside of the integrated module 11 through the reducing gas outlet 1151 of the reducing gas discharge unit 115. The ammonium carbonate produced by the reaction of the reducing gas and the ammonia gas is discharged to the outside of the integrated module 11 through the ammonium carbonate salt outlet 1153.

Body portion 111 has a rectangular parallelepiped shape. The cross-sectional area of the guide part 113 connected to the body part 111 gradually increases along the advancing direction of the reducing gas, that is, closer to the body part 111. That is, the guide portion 113 is formed in the shape of a cone or a polygonal pyramid. As a result, the mixed gas does not concentrate in the center and spreads well evenly to the side. The reducing gas discharged from the reduction furnace (not shown) flows well into the body 111 through the reducing gas injection hole 1131. In addition, ammonia gas is introduced into the integrated module 11 through the ammonia gas injection port 1133. The shape of the guide portion 113 may be modified as necessary. Hereinafter, the internal structure of the integrated module 11 will be described in more detail with reference to FIG. 4.

FIG. 4 schematically shows a cross-sectional structure in which the integrated module 11 is cut along the line IV-IV of FIG. 3. The cross-sectional structure of the integrated module 11 of FIG. 4 is merely for illustrating the present invention, but the present invention is not limited thereto.

As shown in FIG. 4, the porous plate 1111 is provided in the body portion 111. Through the plurality of openings 1111a formed in the porous plate 1111, the reducing gas is injected downward along the dotted arrow direction. In the guide part 113, a guide vane 1117 surrounds the reducing gas inlet 1117 to guide the reducing gas into the integrated module 11. The guide vane 1117 is formed to be inclined at an acute angle with the surface of the guide portion 113. Accordingly, the guide gas 113 is used together with the guide vane 1117 to guide the reducing gas. In particular, since the cross-sectional area of the guide vane 1117 gradually increases toward the body portion 111, it is effective for guiding the reducing gas. The number and shape of the porous plate 1111 and the plurality of openings 1111a may be variously modified as necessary.

On the other hand, the fin tube 1113 is formed surrounding the inside of the body portion 111. The fin tube 1113 is formed in a bundle shape to calculate the amount of cooling heat according to the mixed gas component, flow rate and flow rate to set the fin shape, the fin spacing, the tube shape and the tube spacing. In addition, it is determined whether to proceed with cooling using the refrigerant according to the temperature and flow rate conditions of the mixed gas. Cooling water is supplied to the fin tube 1113 to indirectly cool the reducing gas injected through the openings 1111a. As a result, the reducing gas and the ammonia gas react with each other on the surface of the fin tube 1113 to form ammonium carbonate. Cleaning steam may be irradiated to the fin tube 1113 to liquefy the ammonium carbonate salt attached to the fin tube 1113 and then discharged through the ammonium carbonate salt outlet 1153. Meanwhile, as carbon dioxide is removed as the ammonium carbonate is generated, the purified reducing gas is discharged to the outside through the reducing gas discharge unit 1151.

FIG. 5 schematically shows an apparatus for manufacturing molten iron 1000 including the reducing gas purification apparatus 100 of FIG. 2. The apparatus for manufacturing molten iron in FIG. 5 is merely for illustrating the present invention, but the present invention is not limited thereto. Therefore, the apparatus for manufacturing molten iron of FIG. 5 may be modified in other forms.

As shown in FIG. 5, the molten iron manufacturing apparatus 1000 includes a fluidized bed reduction furnace 20, a molten gasifier 10, a reducing gas supply pipe 40, a reducing gas purifying apparatus 100, and a compacted body manufacturing apparatus. 30 and the like. The fluidized-bed reduction reactor 20 includes four bubble fluidized beds 24, 25, 26, 27. In addition, the molten iron manufacturing apparatus 1000 further includes a high temperature uniform back pressure device 62 and a compacted material storage tank 66.

Iron ore is supplied to the fluidized-bed reduction furnace 20 is reduced while flowing in the bubble stages (24, 25, 26, 27) of the multi-stage. The first bubble fluidized bed 24 preheats the iron ore with reducing gas discharged from the second bubble fluidized bed 25. The second bubble fluidized layer 25 and the third bubble fluidized layer 26 preliminarily reduce the preheated iron ore. The fourth bubble fluidized bed 27 finally converts the preliminarily reduced iron ore into reduced iron.

Iron ore is reduced and heated while passing through the fluidized-bed reduction furnace 20. The reducing gas generated and discharged from the melt gasifier 10 is supplied to the fluidized bed reduction furnace 20 through a reducing gas supply pipe 40. The cyclone 44 prevents scattering of fine powder contained in the reducing gas discharged from the melting gasifier 50. The fine powder is collected by the cyclone 44 and flows back into the melt gasifier 50. The reduced iron produced in the fluidized bed reduction furnace 20 is produced as reduced iron compacted material by the reduced iron compacted material manufacturing apparatus 30.

The reduced iron compacted body manufacturing apparatus 30 contains the charging hopper 31, the pair of roll 33, the crusher 35, and the storage tank 37. As shown in FIG. In addition, the reduced iron compacted material manufacturing apparatus 30 may further include another apparatus as needed. The charging hopper 31 stores reduced iron. The reduced iron is press-molded in strip form while charging from the charging hopper 31 to the pair of rolls 33. The pressed iron compacted compact is crushed in the crusher 35 and stored in the storage tank 37. Since the iron-containing compacted material is smaller than the reduced iron compacted material, it is suitable to be reduced while flowing in the fluidized-bed reduction reactor 20.

The reduced iron stored in the reservoir 37 is transferred to the high temperature uniform back pressure device 42. The high temperature uniform pressure-reducing apparatus 12 controls the pressure between the reduced iron compacted material manufacturing apparatus 30 and the molten gasification furnace 50 to feed the reduced iron compacted material into the molten gasification furnace 50. The reduced iron compacted storage tank 46 temporarily stores the reduced iron compacted material and charges the reduced iron compacted material into the molten gasification furnace 50. And the mass carbon material is supplied to the molten gasifier 50 is burned by the oxygen supply while melting the reduced iron to produce molten iron.

The reducing gas discharged from the first bubble fluidized bed 24 is collected in the water treatment device 51 and then supplied to the reducing gas purification device 100 through the exhaust gas pipe 50. The reducing gas purified by the reducing gas purification apparatus 100 removes dust while passing through the cyclone 64. The purified reducing gas may be supplied to the fourth bubble fluidized bed 27 through the reducing gas supply pipe 40 together with the reducing gas generated in the molten gasifier 60 to reduce the iron ore.

FIG. 6 schematically shows another apparatus for manufacturing molten iron 2000 including the reducing gas purification apparatus 100 of FIG. 2. Since the molten iron manufacturing apparatus 2000 of FIG. 6 includes a portion common to the molten iron manufacturing apparatus 1000 of FIG. 5, the same reference numerals are used for the same portions, and a detailed description thereof will be omitted.

As shown in FIG. 6, iron ore is charged into a packed-bed reduction reactor 67 and reduced by reducing gas supplied from the molten gasifier 60 to form reduced iron. The reduced iron is charged into the melt gasifier 60 and melted. In order to melt the reduced iron, the bulk carbonaceous material is charged into the melting gasifier 60, and oxygen is blown to heat the mass carbonaceous material.

The reducing gas discharged from the packed-bed reduction reactor 67 passes through the exhaust gas pipe 50 and enters the reducing gas purification apparatus 100. The reducing gas purified by the reducing gas purification apparatus 100 passes through the cyclone 64 and then is supplied to the packed-bed reduction reactor 67. In addition to the reducing gas generated in the melt gasifier 60 and provided to the packed-bed reduction reactor 67, the reducing gas refined by the reducing gas purification apparatus 100 is additionally supplied, thereby greatly increasing the fuel cost of the molten iron manufacturing apparatus 2000. Can be lowered.

Experimental Example

Hereinafter, the present invention will be described in more detail with reference to experimental examples. These experimental examples are only for illustrating the present invention, and the present invention is not limited thereto.

Process simulation was performed using Aspen Plus. An experiment on the reducing gas was conducted by process simulation. Process simulation was performed to reflect the ionization tendency and the kinetic theory in the liquid phase, and an appropriate model was selected according to the gas composition. The rest of the experimental process is easily understood by those skilled in the art, and detailed description thereof will be omitted.

Experimental Example 1

An experiment was conducted to separate carbon dioxide into ammonium carbonate through cooling. Ammonia gas was supplied and mixed to treat 270,000 Nm ³ / hr of reducing gas discharged from the melt gasifier. In addition, the mixed gas was indirectly cooled to remove carbon dioxide and the separation performance of the reducing gas was confirmed.

Comparative Example 1

As in the prior art, an experiment was performed to separate carbon dioxide by pressure circulation adsorption after pressurization. That is, 270,000 Nm ³ / hr of reducing gas discharged from the melt gasifier was pressurized. The carbon dioxide was removed by the pressure cycling adsorption and the reducing gas was separated to confirm the plant operation data. At high pressure, carbon dioxide and moisture, which are impurities in the exhaust gas, were adsorbed to the adsorbent to separate reducing gases such as carbon monoxide and hydrogen.

Experiment result

The production amount and composition of the reducing gas prepared according to Experimental Example 1 and Comparative Example 1 described above were measured. In addition, the amount and composition of the tail gas discharged after carbon dioxide removal were measured. The results are summarized in Table 1 below.

It was found that the flow rate of the reducing gas of Experimental Example 1 was increased by 30% compared to the flow rate of the reducing gas of Comparative Example 1. That is, the reduction gas recovery rate was improved from 80% of Comparative Example 1 to 100% of Experimental Example 1. On the other hand, the amount of H ₂ slightly decreased, but the amount of CO and CH ₄ increased, and the amount of CO ₂ and N ₂ decreased. As the production amount of the reducing gas increased in this way, it was possible to reduce the fuel cost in the reduction furnace. And it was confirmed that CO ₂ , H ₂ , CH ₄ and N ₂ were removed from the tail gas of Experimental Example 1. Therefore, when the tail gas is discharged to the outside, it is unnecessary to have additional equipment for transport and treatment, thereby reducing equipment costs and operation costs.

On the other hand, in the pressure circulation adsorption method of Comparative Example 1, a loss occurred in the reducing gas. In addition, frequent pressure changes caused continuous equipment failures, making it difficult to maintain the equipment.

Although the present invention has been described above, it will be readily understood by those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the claims set out below.

10. Gas Mixer
11. All-in-one module
12. Gas Cooler
14. Ammonium Carbonate Decomposer
16. Ammonia Burner
18. Pelletizer
19. Water treatment device
20. Fluidized Bed Reduction Furnace
21. Reduction Furnace
24, 25, 26, 27. Bubble Fluidized Bed
30. Reduced iron compacted material manufacturing apparatus
31.Charge Hopper
33. A pair of rolls
35. Crushers
37. reservoir
40. Reducing gas supply line
50. Exhaust Pipe
51. Water treatment device
60. Melt Gasifier
62. High Temperature Balancing Device
64. Cyclone
66. Compacted reservoir
67. Packed Bed Type Reduction Furnace
100. Reduction gas purification device
111.Body
113. Guide section
115. Reducing gas discharge part
1000, 2000. molten iron manufacturing apparatus
1111.Perforated Plate
1111a. Openings
1113.FinTube
1115. Steam inlet
1117.Guide Vane
1131.Reducing gas inlet
1133.Ammonia gas inlet
1151. Reducing gas outlet
1153. Ammonium Carbonate Outlet

Claims (9)

delete delete delete A gas mixer which receives a reducing gas from a reduction furnace and mixes it with ammonia gas to provide a mixed gas,
A gas cooler that receives the mixed gas to cool the mixed gas to form ammonium carbonate to remove carbon dioxide contained in the mixed gas to provide a purified reducing gas;
Ammonium carbonate decomposer receiving the ammonium carbonate to liquefy the ammonium carbonate, pyrolyzing with carbon dioxide and ammonia, and washing the ammonia to provide ammonia water, and
An ammonia heater that heats the ammonia water to generate the ammonia gas and provide it to the gas mixer
Including,
The gas mixer and the gas cooler are formed as an integrated module,
The integrated module,
Body Part,
A guide part connected to the body part and having a reducing gas injection hole through which the reducing gas is introduced, and a cross-sectional area thereof gradually increasing toward the body part;
A porous plate installed in the body portion and having a plurality of openings formed therein;
A fin tube surrounding the inner side of the body part and indirectly cooling the reducing gas injected through the plurality of openings while cooling water is supplied and circulated, thereby producing the ammonium carbonate salt on the surface thereof; and
A reducing gas discharge part connected to the body part and discharging the purified reducing gas to the outside
Including,
The guide unit further comprises a steam injection port for liquefying the ammonium carbonate salt by irradiating the steam to the fin tube further reduction device. delete delete In claim 4,
And a guide vane formed in the guide part to surround the reducing gas inlet while forming an acute angle with the surface of the guide part, and having a cross-sectional area gradually widening toward the body part. A reduction furnace in which iron ore is charged and a reducing gas is supplied,
Reducing gas purification apparatus according to claim 4 connected to the reduction furnace, and
The reducing gas purifier is connected to the reducing gas purifier and the reducing furnace to supply the reducing gas to the reducing furnace, and the reduced iron in which the iron ore is reduced is charged and melted in the reducing furnace.
Molten iron manufacturing apparatus comprising a. In claim 8,
The reduction furnace is molten iron manufacturing apparatus which is a fluidized bed reduction furnace or packed bed reduction furnace.

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