WO2019022319A1

WO2019022319A1 - Sodium bicarbonate preparation apparatus using combustion exhaust gas and sodium bicarbonate preparation method using same

Info

Publication number: WO2019022319A1
Application number: PCT/KR2018/000188
Authority: WO
Inventors: 이지현; 이동욱; 심재구; 곽노상; 이정현; 류순도
Original assignee: 한국전력공사; 한국동서발전(주)
Priority date: 2017-07-28
Filing date: 2018-01-04
Publication date: 2019-01-31
Also published as: KR101951617B1; CN109588048B; KR20190014209A; CN109588048A

Abstract

The present invention relates to a sodium bicarbonate preparation apparatus using combustion exhaust gas and a sodium bicarbonate preparation method using the same. In one specific embodiment, the sodium bicarbonate preparation apparatus using the combustion exhaust gas comprises: a first reactor for bringing a caustic soda solution supplied from the upper portion thereof and the combustion exhaust gas flowing in from the lower portion thereof in contact with each other so as to produce a first treated gas and a first slurry; and a second reactor including a first reaction part formed at the lower portion thereof, and a second reaction part formed at the upper portion of the first reaction part so as to communicate with the first reaction part, allowing the first treated gas to branch into the lower portion of the first reaction part and the lower portion of the second reaction part and flow thereinto through a first gas line, and allowing the first treated gas having flowed into the lower portion of the first reaction part and the lower portion of the second reaction part to respectively come in contact with the caustic soda solution flowing in from the upper portion of the second reaction part.

Description

A device for producing bicarbonate using combustion gas and a method for producing bicarbonate using the same

The present invention relates to a device for producing bicarbonate using combustion gas and a method for producing bicarbonate using the same.

A number of processes have been studied to remove carbon dioxide from flue gas emitted from a power plant that is the cause of global greenhouse gases. Among them, a method of removing carbon dioxide by a wet absorption method using monoethanolamine (MEA) Is capable of large-scale processing at normal pressure, but it has disadvantages of large installation cost and high energy consumption due to the large scale of treatment facilities due to characteristics of gas stream such as atmospheric pressure.

In recent years, studies have been actively conducted to produce a high-value compound such as sodium bicarbonate using a continuous flue gas discharged from a coal-fired power plant, and at the same time to reduce carbon dioxide, a representative greenhouse gas.

Prior art relating to the present invention is Japanese Patent Laid-Open Publication No. 1999-104440 (published on Apr. 20, 1999, entitled " Method and apparatus for removing acidic gas in exhaust gas "). This document discloses a reactor comprising a vertical reactor having an inlet for flue gas at the bottom and an outlet for flue gas at the top, a means for injecting the slurry into the vertical reactor, a separator for separating dry solids contained in the flue gas from the reactor, And a recycle furnace for recirculating a part of the exhaust gas to the reactor.

One object of the present invention is to provide an apparatus for producing bicarbonate using an excellent flue gas having excellent carbon dioxide removal efficiency and environment friendliness and capable of producing high purity bicarbonate.

Another object of the present invention is to provide an apparatus for producing bicarbonate using flue gas having excellent economy, productivity and environment friendliness.

It is still another object of the present invention to provide a method for producing bicarbonate using the apparatus for producing bicarbonate using the flue gas.

One aspect of the present invention relates to an apparatus for producing bicarbonate using combustion gas. In one embodiment, the apparatus for producing bicarbonate using the combustible gas comprises a first reaction tower in which a caustic soda solution supplied from an upper part and a combustible gas introduced from a lower part contact with each other to produce a first process gas and a first slurry; And a second reaction unit formed on the first reaction unit and communicating with the first reaction unit, wherein the first process gas is supplied to the first reaction unit through the first gas line, The first process gas flowing into the lower part of the first reaction part and the lower part of the second reaction part and flowing into the lower part of the first reaction part and the lower part of the second reaction part, 2 reaction tower, wherein the first slurry and the unreacted caustic soda solution stay in the lower part of the first reaction tower to form a first mixed slurry, To a slurry drying unit provided at a lower portion of the slurry drying unit to produce sodium bicarbonate.

In one embodiment, a portion of the first mixed slurry may be recycled through the first circulation line to the top of the first reaction column.

In one embodiment, the second reaction tower may include a gas dispersion unit between the first reaction unit and the second reaction unit, wherein the gas dispersion unit has a plurality of holes formed on an inner circumferential surface thereof, The first process gas may be introduced into the lower portion of the second reaction unit through the plurality of holes.

In one embodiment, the first process gas introduced into the lower part of the first reaction part and the lower part of the second reaction part is in contact with the caustic soda solution flowing in from the upper part of the second reaction part to form the second process gas, the second slurry, 3 slurry, wherein the second slurry, the third slurry and the unreacted caustic soda solution remain in the lower portion of the first reaction section to form a second mixed slurry, and a part of the second mixed slurry forms the first slurry Can be circulated to the upper part of the first reaction part through the second circulation line provided at the lower part of the reaction part and can be in contact with the first process gas.

In one embodiment, a portion of the second mixed slurry may flow into the upper portion of the first reactor through a first feed line disposed below the first reactor to contact the flue gas.

In one embodiment, the pH of the first mixed slurry produced in the lower portion of the first reaction tower may be about 8.5 to about 9.0.

In one embodiment, the pH of the second slurry produced in the first reaction section is from about 10 to about 11, and the pH of the third slurry produced in the second reaction section may be from about 11 to about 12. [

In one embodiment, the diameters of the first reaction tower and the second reaction tower may be such that the linear velocities of the incoming combustion gas and the first process gas are respectively about 50 m / hr to about 80 m / hr.

In one embodiment, the height H1 of the first reaction tower and the height H2 of the second reaction tower may be about 80 cm to about 200 cm, respectively.

In one embodiment, the height H1 of the first reaction tower and the height H2 of the second reaction tower may be about 12 to about 15 times the diameter of the first reaction tower and the second reaction tower.

In one embodiment, the slurry drying unit includes: separating means for separating the transferred first slurry into a powdery and slurry filtrate through a separation membrane; Drying means for drying the powder to produce bicarbonate; And separating the first mixed slurry into powdery and slurryy filtrate by using vibrational energy, and separating the separated slurryy filtrate from the separated mixed slurry, And may be introduced into the upper portion of the first reaction column.

In one embodiment, the drying means may dry the powder at about 40 ° C to about 70 ° C.

Another aspect of the present invention relates to a method for producing bicarbonate using the apparatus for producing bicarbonate. For example, the caustic soda solution supplied from the upper part of the first reaction tower and the combusted gas flowing from the lower part contact each other to produce a first process gas and a first slurry. And the first process gas flows into the lower part of the first reaction part and the lower part of the second reaction part of the second reaction column through the first gas line and flows into the lower part of the first reaction part and the lower part of the second reaction part, Contacting the first process gas with a caustic soda solution introduced from the top of the second reaction section, wherein the first slurry and the unreacted caustic soda solution remain in the lower portion of the first reaction column, And the first mixed slurry is transferred to a slurry drying unit provided at a lower portion of the first reaction tower to produce sodium bicarbonate.

When the apparatus for producing bicarbonate of the present invention and the manufacturing method of the present invention are applied, the carbon dioxide removal efficiency is excellent, and it is possible to manufacture a high-purity bicarbonate with a small-scale processing facility and a low cost, thereby being excellent in economy, productivity and environment friendliness.

FIG. 1 shows an apparatus for producing bicarbonate using flue gas according to one embodiment of the present invention.

Fig. 2 (a) shows a cross section of a gas dispersion part according to one embodiment of the present invention, and Fig. 2 (b) shows the gas dispersion part.

3 shows a separating means of the slurry drying unit according to one embodiment of the present invention.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

연소배가스를Combustible gas 이용한 중탄산소다 제조장치 Bicarbonate production equipment used

One aspect of the present invention relates to an apparatus for producing bicarbonate using combustion gas. FIG. 1 shows an apparatus for producing bicarbonate using flue gas according to one embodiment of the present invention. Referring to FIG. 1, the apparatus for producing bicarbonate 1000 using a combustion gas includes a first reaction, in which a caustic soda solution supplied from an upper part and a combustible gas introduced from a lower part are brought into contact with each other to produce a first process gas and a first slurry A tower 200; And an upper part of the first reaction part A1 and the first reaction part A1 formed at the lower part. And a second reaction part (A2) communicating with the first reaction part (A2), wherein the first process gas is supplied through the first gas line (20) to the lower part of the first reaction part (A1) The first process gas flowing into the lower part of the second reaction part A2 flows into the lower part of the second reaction part A2 and flows into the lower part of the second reaction part A2, And a second reaction tower (300) for producing a second process gas, a third process gas, a second slurry and a third slurry, respectively, in contact with the solution.

NaOH (sodium hydroxide) may be introduced into the upper portion of the first reaction tower 200 by a conventional method. For example, caustic soda may be introduced into the upper part of the first reaction tower 200 and a supply line (not shown) connected to the caustic soda supply unit 400 to be described later.

The combustible gas is discharged from the combustion of fossil fuel in a coal-fired power plant, a cement plant, a petrochemical plant, etc., and a gas containing carbon dioxide (CO ₂ ) can be used. The concentration of carbon dioxide in the combustible gas may be determined by the fuel used in a power plant or a cement factory and a combustion method. In one embodiment, the carbon dioxide in the flue gas may comprise about 13% to about 16% by volume of flue gas generated in a coal-fired power plant. In another embodiment, in the case of flue gas generated in a steelmaking furnace or the like, the carbon dioxide may comprise from about 20% by volume to about 23% by volume. If the concentration of carbon dioxide in the flue gas is high, the amount of carbon dioxide that can be treated at the same reactor scale increases, which is advantageous.

Referring to FIG. 1, the flue gas may flow into the lower portion of the first reaction tower 200 through the flue gas inlet line 10. In one embodiment, the flue gas may be cooled through the gas cooling unit 100 and introduced into the lower portion of the first reaction tower 200. When the combustible gas is cooled, the reaction efficiency increases, and the carbon dioxide removal efficiency of the first process gas can be excellent. The combustion gas inflow line 10 may further include a gas blower or the like to introduce the combustible gas into the first reaction tower 200.

Upon contact between the caustic soda solution and the flue gas, a carbonation reaction as shown in the following chemical formulas (1) and (2) is generated to produce a first process gas and a first slurry in which carbon dioxide contained in the flue gas is removed:

[Chemical Formula 1]

CO ₂ (g) + 2NaOH (1) - > Na ₂ CO ₃ + H ₂ O

(2)

Na ₂ CO ₃ + CO ₂ (g) + H ₂ O → 2NaHCO ₃

Referring to FIG. 1, a first filling material 210 may be included in the first reaction tower 200. As the above-mentioned filling material, a conventional one can be used. For example, an amorphous fill material can be used. When the first filler material 210 is included, the residence time for contact between the combustible gas and the caustic soda is increased to minimize the size of the reaction tower with excellent reaction efficiency.

The first slurry and the combustible gas and the unreacted caustic soda solution are retained in the lower part of the first reaction tower 200 to form a first mixed slurry M 1, 1 mixed slurry M1 can maintain a constant liquid level.

In one embodiment, a portion of the first mixed slurry M1 is recycled into the upper portion of the first reaction column 200 through the first circulation line 70 provided in the lower portion of the first reaction column 200, / RTI > For example, circulated through the first circulation pump 72 provided in the first circulation line 70. When the first mixed slurry is circulated under the above conditions, the residence time necessary for the carbonation reaction between the carbon dioxide and the caustic soda solution in the combustible gas is increased through the circulation of the first mixed slurry (M1), so that the carbon dioxide The reaction efficiency between caustic soda is increased, which can contribute greatly to reducing the size (or reactor volume) of the entire column.

2 shows a gas dispersion unit according to one embodiment of the present invention. Referring to FIGS. 1 and 2, the first process gas includes a gas dispersion unit 320 disposed between the first reaction unit A1 and the first reaction unit A1 and between the first reaction unit A1 and the second reaction unit A2. Through the gas inlet 321 of the gas inlet 321. In one embodiment, the first process gas may flow into the second reaction unit through a plurality of holes 322 formed in the inner circumferential surface of the gas dispersion unit 320.

Referring to FIG. 1, filling

materials

310 and 312 may be contained in the first reaction part A1 and the second reaction part A2, respectively. As the above-mentioned filling material, a conventional one can be used. For example, a static filling material in the form of a metal sheet or a structured packing may be used. When the

filler

310 or 312 is included, the residence time for contacting the first process gas with the caustic soda is increased to minimize the size of the reaction tower with excellent reaction efficiency.

In one embodiment, the first process gas in which the carbon dioxide is removed by contact with the caustic soda solution in the first reaction section A1 is reused in the second reaction section A2 communicating with the first reaction section A1, Solution and is combined with the first process gas from which carbon dioxide has been removed in the second reaction section A2 to form a second process gas.

Referring to FIG. 2, the second slurry, the third slurry, the first process gas and the unreacted caustic soda solution are retained in the lower portion of the first reaction unit A1 to separate the second mixed slurry M2 into the first The second mixed slurry M2 under the reaction part A1 can maintain a constant liquid level.

A part of the second mixed slurry M2 is circulated to the upper part of the first reaction part A1 through the second circulation line 50 provided in the lower part of the first reaction part A1, / RTI > For example, the second mixed slurry may be recycled to the upper portion of the first reaction unit A1 using a second circulation pump 52 provided in the second circulation line 50. [

Part of the first and second mixed slurries may be added to the upper portion of the first reactor 200 and the upper portion of the first reactor A1 in an amount of about 5 liter / kg · mol CO ₂ to about 30 liter / kg · mol CO ₂ Respectively. Under the above conditions, the efficiency of producing bicarbonate can be excellent.

1, the second mixed slurry M2 flows into the upper part of the first reaction column 200 through a first transfer line 60 provided below the first reaction part A1, It can come into contact with the combustion gas.

In one embodiment, the pH of the first slurry produced in contact with the upper portion of the first reactor 200 may be about 8.5 to about 11.0. In the above range, the reactivity is excellent, and the productivity and quality of sodium bicarbonate can be excellent. The pH of the first mixed slurry M1 under the first reaction column 200 may be adjusted to about 8.5 to about 9.0. Under the above conditions, the purity of the bicarbonate produced according to the present invention can be maximized.

When the pH of the first mixed slurry at the lower end of the first reaction tower 200 is less than about 8.5, precipitation due to the lowering of the solubility of the sodium bicarbonate may be generated, the slurry discharge line 80 may be clogged, , The production efficiency of sodium bicarbonate is lowered and the purity is lowered, while the amount of produced sodium carbonate (Na ₂ CO ₃ ) may increase.

In one embodiment, the pH of the second slurry produced in the first reaction part A1 is from about 10 to about 11, and the pH of the third slurry produced in the second reaction part A2 is from about 11 to about 12 days . In the above range, the reactivity is excellent, and the productivity and quality of sodium bicarbonate can be excellent.

A first reaction section (A1) a second slurry pH is, while the content of sodium carbonate (Na ₂ CO ₃₎ increase of the slurry drops to about 10 less than, said first transfer line to the precipitates according to the solubility characteristics of the bicarbonate of the ( 60 is clogged and the pH of the second slurry exceeds about 11, it is difficult to keep the pH of the first mixed slurry (M1) at about 8.5 to about 9.0, so that the purity of the sodium bicarbonate Can be degraded.

1, the caustic soda solution stored in the caustic soda storage unit 400 may be transferred to the upper end of the first reaction unit A1 of the second reaction tower 300 through the caustic soda supply line 40. In one embodiment, the caustic soda may comprise from about 10% to about 30% by weight of the total weight of the caustic soda solution. For example, from about 15% to about 20% by weight.

When the caustic soda is contained in an amount less than about 10 wt.%, The reaction efficiency with carbon dioxide in the flue gas becomes low. Therefore, the purity of the desired sodium bicarbonate can not be obtained in the reaction tower of the present invention. %, It may cause many troubles in terms of long-term operation because precipitates may be formed in the transfer line at a low temperature due to the solubility characteristics of the produced carbonate and bicarbonate as well as the corrosion of the reactor. For example, in the total weight of the caustic soda solution, the caustic soda may be present at a concentration of about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, , 28, 29 or 30% by weight.

As described above, in the apparatus for producing bicarbonate of the present invention, the treatment stream of the combustion gas is supplied from the first reaction tower 200 to the second reaction tower 300 through the flow of the slurry formed by contacting the caustic soda solution and the combustion exhaust gas Are crossed from the second reaction tower 300 to the first reaction tower 100. The optimal pH for the production of high purity sodium bicarbonate can be controlled when the process is performed under the above conditions.

Referring to FIG. 1, a gas discharge line 30 is provided at an upper portion of the second reaction tower 300 to discharge the formed second process gas to the outside.

In one embodiment, the diameters of the first reaction tower and the second reaction tower may be such that the linear velocities of the incoming combustion gas and the first process gas are respectively about 50 m / hr to about 80 m / hr. In the above linear velocity range, the carbonation reaction rate and process efficiency of the present invention can be excellent.

In one embodiment, the height H1 of the first reaction tower and the height H2 of the second reaction tower may be about 80 cm to about 200 cm, respectively. Within the above range, the carbonation reaction rate and process efficiency of the present invention can be excellent. For example, the height H1 of the first reaction tower and the height H2 of the second reaction tower may be about 80 cm to about 150 cm, respectively.

In one embodiment, the height H1 of the first reaction tower and the height H2 of the second reaction tower may be about 12 to about 15 times the diameter of the first reaction tower and the second reaction tower. Within the above range, the carbonation reaction rate and process efficiency of the present invention can be excellent.

In one embodiment, the first reaction tower 200 and the second reaction tower 300 further include a temperature measurement unit, a pH measurement unit, and a conductivity measurement unit, and can perform various condition change analysis during operation .

In one embodiment,

mist eliminators

230 and 330 are provided in the first reaction column 200 and the second reaction column 300 to remove droplets of the first process gas and the second process gas, respectively, Balance can be maintained.

In one embodiment, a carbon dioxide measuring sensor is provided in each of the combustion gas inflow line 10, the first gas line 20 and the gas discharge line 30 to perform analysis of the carbon dioxide removal efficiency (or carbon dioxide conversion) . &Lt; / RTI >

In one embodiment, the first mixed slurry M is transferred to the slurry drying unit 500 provided at the lower part of the first reaction tower 200 to produce sodium bicarbonate. In one embodiment, the slurry drying unit 500 includes: separating means for separating the transferred first mixed slurry M1 into a powdery and slurry filtered liquid through a separation membrane; Drying means for drying the powder to produce bicarbonate; And a bicarbonate soda storage for storing the produced bicarbonate. The separated slurry filtrate may be introduced into the upper part of the first reaction column through a filtrate discharge line.

In one embodiment, the average size of the solid particles of the first mixed slurry may be about 20 탆 or less. For example from greater than about 0 to about 20 microns. The solids content of the first mixed slurry (M1) may be from about 10% to about 20% by weight. Therefore, the dehydration and drying of the first mixed slurry (M1) proceeds in the slurry drying unit, and solid sodium bicarbonate can be obtained.

During the passage of the separation membrane, the first slurry is separated into powder and slurry filtrate by using vibration energy. FIG. 3 shows the separating means 510 of the slurry dryer 500 according to one embodiment of the present invention. 3, the separating means 510 includes a separating membrane 502 separating the powdery and slurry filtrate from the first mixed slurry M1, a vibrating means 504 provided below the separating membrane 502, A filtrate discharge line 510 through which the slurry filtrate passed through the separation membrane is discharged, and a powder storage section 506 through which the powder passing through the separation membrane is stored.

When the vibration energy is applied, the separation membrane itself vibrates at a high frequency to prevent the phenomenon that the fine particles in the first mixed slurry M1 to be separated adhere to the membrane surface to deteriorate the membrane separation efficiency, can do.

The method of removing moisture from the slurry through the diaphragm separation process of the present invention is advantageous in terms of operation and energy efficiency of the drying means. Specifically, most of the water containing the residual impurities in the first mixed slurry is removed through the separation membrane, so that the amount of water to be blown off by spray drying is reduced by the corresponding amount, and energy consumption is greatly reduced.

The powder stored in the powder storage portion 506 may be transferred to a drying means and dried. The water content of the powders subjected to the vibrating separation membrane process may be about 10 wt% to about 20 wt%. Therefore, it is necessary to remove residual water by drying. For example, the drying means may be a fluidized bed dryer. In one embodiment, the drying means is capable of drying the powder using air at about 40 ° C to about 70 ° C. Under the above conditions, the drying efficiency is excellent and pyrolysis of the bicarbonate can be prevented.

In one embodiment, a slurry storage unit (not shown) may be further disposed between the lower portion of the first reaction tower A1 and the slurry drying unit 500. In one embodiment, the first reaction tower 200 may further include a diaphragm-type slurry transfer pump. When the slurry transfer pump is further included, the slurry can be transferred to the slurry drying unit 500 without clogging due to slurry deposition in the slurry discharge line 80.

연소배가스를Combustible gas 이용한 중탄산소다 제조장치를 이용한 중탄산소다 제조방법 METHOD FOR MANUFACTURING SODIUM BICKENBOXIDE BY USING SAME

Another aspect of the present invention relates to a method for producing bicarbonate using the apparatus for producing bicarbonate using the combustible gas. Wherein the caustic soda solution supplied from the upper part of the first reaction tower and the combusted gas flowing from the lower part contact with each other to produce a first process gas and a first slurry; And the first process gas flows into the lower part of the first reaction part and the lower part of the second reaction part of the second reaction column through the first gas line and flows into the lower part of the first reaction part and the lower part of the second reaction part, Wherein the first process gas is in contact with the caustic soda solution introduced from the upper portion of the second reaction section to thereby generate the second process gas, the third process gas, the second slurry, and the third slurry, respectively, 1 slurry and the unreacted caustic soda solution and the unreacted caustic soda solution form a first mixed slurry in a lower portion of the first reaction tower, Line to the upper portion of the first reaction column to be in contact with the combustion gas, and the first mixed slurry is transferred to the slurry drying unit provided in the lower portion of the first reaction column to produce bicarbonate. The bicarbonate device is the same as that described above, so that detailed description thereof will be omitted.

The present invention utilizes combustion exhaust gas discharged from the combustion of fossil fuels in coal-fired power plants, cement and petrochemical plants, and produces carbon dioxide, which is commercially valuable, and reduces carbon dioxide, which is a typical greenhouse gas. .

The sodium bicarbonate produced according to the present invention can be utilized in various industrial fields such as soaps, detergents, food additives, and exhaust gas refining, and has high added value and excellent usability.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

실시예Example 및 And 비교예Comparative Example

실시예Example

Bicarbonate Soda Production Bicarbonate was produced using the apparatus for producing bicarbonate as shown in FIG. The height H1 of the first reaction column and the height H2 of the second reaction column were respectively 150 cm. In the first reaction column 200, the first filling material 210 containing the amorphous filling material 1 is supplied to the upper part of the reaction tower 200 and is cooled through the gas cooling part 100 and flows into the combustion gas inflow line 10 Through the bottom of the first reaction column 200 at a flow rate of 25 liter / min, and contacted with the combustion gas containing carbon 15 to 15 vol% to produce the first process gas and the first slurry.

The first process gas is then introduced into the first reaction section A1 of the second reaction tower 300 and the first reaction section A1 and the second reaction section A2 through the plurality of holes 322 formed in the inner circumferential surface of the gas dispersion unit and flows into the lower portion of the second reaction unit.

At this time, 50% by volume of the branched first process gas was introduced into the lower part of the first reaction part, and 50% by volume was introduced into the second reaction part through the gas dispersion part.

The first process gas flowing into the lower part of the first reaction part and the lower part of the second reaction part and the caustic soda solution (containing 15 wt% of caustic soda, flowing at a flow rate of 45 ml / min) flowing from the upper part of the second reaction part , The second process gas, the third process gas, the second slurry and the third slurry, respectively.

The first slurry, the combustible gas and the unreacted caustic soda solution stayed in the lower part of the first reaction tower to form a first mixed slurry. A part of the first mixed slurry circulates through the first circulation line provided in the lower part of the first reaction tower to the upper part of the first reaction tower and is in contact with the combustible gas.

Also, in the second reaction tower 300, the second slurry, the third slurry, the first process gas and the unreacted caustic soda solution remain in the lower portion of the first reaction unit A1 to form a second mixed slurry And the second mixed slurry circulates through the second circulation line 50 provided in the lower part of the first reaction part A1 to the upper part of the first reaction part to be in contact with the first process gas. Also, a part of the second mixed slurry flows into the upper part of the first reaction tower 200 through the first transfer line 60 provided in the lower part of the first reaction part A1, Respectively.

At this time, the flow rates of the circulating first and second mixed slurries were respectively 50 liter / kg · mol CO ₂ conditions.

The first mixed slurry was transferred to a slurry drying unit provided at a lower portion of the first reaction tower through a slurry discharge line (80). The first mixed slurry was transferred to a separating means, passed through a separation membrane, and separated into a powdery and slurry filtrate. During the passage of the separation membrane, the first mixed slurry was separated into a powdery and slurry filtrate using vibrational energy, the powder was transferred to a drying means and dried at a temperature of 40 ° C to produce bicarbonate, Soda was transferred to the bicarbonate storage and stored. The separated slurry filtrate flowed into the upper part of the first reaction column through a filtrate discharge line.

실시예Example 2 2

The same procedure as in Example 1 was carried out except that the concentration of the caustic soda solution introduced into the upper part of the second reaction column (upper part of the second reaction part) was 20% by weight and the feed amount per minute was adjusted to 30 ml Respectively.

실시예Example 3 3

The same procedure as in Example 1 was carried out except that the amount of caustic soda solution introduced into the upper part of the second reaction tower (upper part of the second reaction part) was adjusted to 30 ml.

실시예Example 4 4

The same procedure as in Example 1 was carried out except that the height of the first and second reaction columns was 200 cm.

비교예Comparative Example 1 One

Without branching the first process gas. Sodium bicarbonate was prepared in the same manner as in Example 1, except that it was added to the lower portion of the first reaction portion of the second reaction column.

비교예Comparative Example 2 2

Without branching the first process gas. Sodium bicarbonate was prepared in the same manner as in Example 1 except that it was added to the lower portion of the second reaction portion of the second reaction column.

Table 1 shows the operation results of the continuous operation for 3 hours with respect to Examples 1 to 4 above.

Referring to the results shown in Table 1, the carbon dioxide capture ratio (conversion ratio) of the Example 1 was kept constant at 90% or more, and the XRD and X-ray diffraction purity of the obtained powder was 98% And there was no significant difference from the purity of commercially available products.

Next, in Examples 2 and 3, the heights of the reactors were the same, and the results were obtained by changing the amount or concentration of caustic soda. As a result of the operation, the average capture ratio of carbon dioxide was over 90%, which was very good. However, during operation for more than 2 hours, sediment was formed on the line and clogged frequently.

Table 1 shows the operation results of the continuous operation for 3 hours in Example 1 and Comparative Examples 1 and 2. In order to secure the reliability of the operation result, a carbonation reaction model capable of simulating Example 1 and Comparative Examples 1 and 2 was constructed using the pre-established process simulation tool (gPROMS, PSE) The carbon dioxide conversion rate under the same conditions was analyzed, and the results of the analysis in comparison with the continuous operation test are shown in Table 2.

Referring to Table 2, it was analyzed that the average carbon dioxide capture ratio (conversion ratio) of Comparative Example 1 and Comparative Example 2 was lower than that of Example 1. As described in the detailed description of the present invention, in the case of Example 1, the first reaction is performed in the second reaction portion of the second reaction column operated in a region having a relatively high pH (pH range of the third slurry: 11 to 12) In the first reaction part (the second slurry pH range: 10 to 11) in which a considerable part of the exhaust gas discharged from the tower is introduced to induce the carbonation reaction under a short residence time and the reaction is performed in a lower pH range than the second reaction part It is judged that the first process gas branched from the first reaction column is subjected to the first reaction in the first reaction part of the second reactor and then the second reaction part again in the second reaction part so that the conversion of carbon dioxide is improved as compared with the comparative examples 1 and 2 .

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

A first reaction tower for contacting the caustic soda solution supplied from the upper part and the combustion gas flowing from the lower part to generate a first process gas and a first slurry; And

And a second reaction part formed on the first reaction part and communicating with the first reaction part, wherein the first process gas is supplied to the first reaction part through the first gas line, The first process gas introduced into the lower part of the first reaction part and the lower part of the second reaction part flows into the lower part of the second reaction part, 2 reaction tower,

The first slurry and the unreacted caustic soda solution stay in the lower part of the first reaction tower to form a first mixed slurry,

Wherein the first mixed slurry is transferred to a slurry drying unit provided in a lower portion of the first reaction tower to produce sodium bicarbonate.
The apparatus for producing bicarbonate using combustion gases according to claim 1, wherein a part of the first mixed slurry circulates through the first circulation line to the upper part of the first reaction tower.
The apparatus according to claim 1, wherein the second reaction tower has a gas dispersion unit between the first reaction unit and the second reaction unit,

Wherein the gas dispersion portion has a plurality of holes formed in an inner peripheral surface thereof,

Wherein the first process gas flows into the lower portion of the second reaction unit through the plurality of holes.
The apparatus for producing bicarbonate according to claim 1, further comprising a slurry storage part between the lower part of the first reaction tower and the slurry drying part.
The method according to claim 1, wherein the first process gas flowing into the lower portion of the first reaction portion and the lower portion of the second reaction portion is in contact with the caustic soda solution flowing in the upper portion of the second reaction portion, And a third slurry,

The second slurry, the third slurry, and the unreacted caustic soda solution stay in the lower part of the first reaction part to form a second mixed slurry,

Wherein a part of the second mixed slurry circulates through the second circulation line provided below the first reaction unit to the upper portion of the first reaction unit and is in contact with the first process gas. Bicarbonate production equipment.
6. The method according to claim 5, wherein a part of the second mixed slurry flows into an upper part of the first reaction column through a first transfer line provided below the first reaction part and is in contact with the combustible gas A device for producing bicarbonate using combustion gas.
The apparatus for producing bicarbonate using combustible gas according to claim 1, wherein the pH of the first slurry generated in the lower part of the first reaction tower is about 8.5 to about 9.0.
6. The method according to claim 5, wherein the pH of the second slurry produced in the first reaction part is about 10 to about 11,

And the pH of the third slurry produced in the second reaction part is about 11 to about 12. The apparatus for producing bicarbonate using combustion gas according to claim 1,
[3] The apparatus of claim 1, wherein the first reaction column and the second reaction column have a diameter of about 50 m / hr to about 80 m / hr, respectively, Wherein the flue gas is a flue gas.
The apparatus for producing bicarbonate using combustion gas according to claim 1, wherein the first reaction tower height (H1) and the second reaction tower height (H2) are about 80 cm to about 200 cm, respectively.
The method according to claim 1, wherein the first reaction tower height (H1) and the second reaction tower height (H2) are about 12 to about 15 times the diameter of the first reaction tower and the second reaction tower Wherein the flue gas is a flue gas.
The method according to claim 1, wherein the slurry drying unit comprises: separating means for separating the transported first mixed slurry into a powdery and slurry filtrate through a separation membrane;

Drying means for drying the powder to produce bicarbonate; And

And a bicarbonate storage unit for storing the generated bicarbonate,

Separating the first mixed slurry into a powdery and slurry filtrate by using vibrational energy,

And the separated slurry filtrate flows into the upper portion of the first reaction column.
The apparatus for producing bicarbonate using combustion gases according to claim 11, wherein the drying means is to dry the powder at about 40 ° C to about 70 ° C.
A method for producing bicarbonate using the apparatus for producing bicarbonate of claim 1,

Generating a first process gas and a first slurry by contacting a caustic soda solution supplied from an upper part of the first reaction tower and a combusted gas flowing from a lower part; And

The first process gas flows into the lower part of the first reaction part and the lower part of the second reaction part of the second reaction column through the first gas line and flows into the lower part of the first reaction part and the lower part of the second reaction part, One process gas is contacted with a caustic soda solution introduced at the top of the second reaction section,

The first slurry and the unreacted caustic soda solution stay in the lower part of the first reaction tower to form a first mixed slurry,

Wherein the first mixed slurry is transferred to a slurry drying unit provided at a lower portion of the first reaction tower to produce bicarbonate.