KR102205282B1 - Method and apparatus of sodium bicarbonate production - Google Patents

Abstract

The present invention relates to an apparatus and method for preparing sodium bicarbonate and, more particularly, to an apparatus and method for preparing sodium bicarbonate, which comprises the steps of: supplying an aqueous sodium carbonate solution generated in a caprolactam (C_6H_11NO) production process; supplying combustion exhaust gas containing carbon dioxide (CO_2); preparing sodium bicarbonate (NaHCO_3) slurry by subjecting the aqueous sodium carbonate solution and the combustion exhaust gas to a bicarbonation reaction in a bubble column containing a micro-bubbler; and transferring the sodium bicarbonate slurry to a dehydration process to separate into powder and mother liquid.

Description

Sodium bicarbonate production apparatus and method for producing the same TECHNICAL FIELD [Method and apparatus of sodium bicarbonate production]

The present invention relates to an apparatus for producing sodium bicarbonate and a method for producing sodium bicarbonate.

In recent years, as the importance of the environment increases, regulations on carbon dioxide in the atmosphere are becoming very severe. In particular, with the entry into force of the Kyoto Protocol, we are actively responding to these regulations for the survival of various domestic industries, as we are focusing on reducing the amount of carbon dioxide generated, which has the largest total domestic emissions, and the contribution to the greenhouse effect, and the amount of carbon dioxide generated worldwide. I need this.

Along with the reduction of carbon dioxide, which is a representative greenhouse gas, there is an urgent need to reduce carbon dioxide in power plants, and research on technology for separating and recovering carbon dioxide is currently underway.

However, operating a facility for separating and recovering carbon dioxide has a disadvantage in that very high energy is consumed. Therefore, there is a need to develop a device capable of manufacturing a high value-added compound using exhaust gas including carbon dioxide emitted.

On the other hand, caprolactam is made using cyclohexane, ammonia and sulfur obtained from crude oil as main ingredients, nylon fibers used in the manufacture of clothes, tire cords, fishing nets, carpets, and nylon resins used in the manufacture of mechanical parts and engineering plastics. It is used as a raw material for Such caprolactam is produced as a by-product of the process and generates an aqueous solution of sodium carbonate with a scale of 10,000 tons per month, which incurs a large treatment cost. Accordingly, some aqueous solutions of sodium carbonate are used for neutralization treatment of wastewater, but research to treat them is continuing.

The technical problem to be solved of the present invention is a manufacturing method for producing sodium bicarbonate using carbon dioxide contained in combustion exhaust gas discharged from a thermal power plant, a cement, and a petrochemical plant, and an aqueous solution of sodium carbonate generated in the production process of caprolactam, and It is an object to provide a manufacturing apparatus.

According to an aspect of the present invention for achieving the above object, in the apparatus for producing sodium bicarbonate using combustion flue gas and caprolactam (C ₆ H ₁₁ NO) production by-product, caprolactam (C ₆ H ₁₁ NO) A sodium carbonate aqueous solution supply unit for supplying an aqueous solution of sodium carbonate generated in the production process, a combustion exhaust gas supply unit for supplying combustion exhaust gas containing carbon dioxide (CO ₂ ), the sodium carbonate aqueous solution and the combustion exhaust gas undergo a bicarbonate reaction to form a bicarbonate slurry. It provides an apparatus for producing sodium bicarbonate comprising a gas-liquid bubble tower to be prepared, and a dehydration unit for transferring the sodium bicarbonate slurry to separate powder and mother liquor.

According to an embodiment of the present invention, the gas-liquid bubble tower may further include a microbubbler for supplying the aqueous solution of sodium carbonate and the combustion exhaust gas.

According to an embodiment of the present invention, the microbubbler includes a first microbubbler for supplying combustion exhaust gas including carbon dioxide, and the first microbubbler is located under the gas-liquid bubbler. It may be located.

According to an embodiment of the present invention, the microbubbler includes a second microbubbler for supplying the demand solution of soda carbonate, and the second microbubbler is located above the gas-liquid bubble tower. I can.

According to an embodiment of the present invention, the dehydration unit may further include a vibration separation membrane for separating the prepared heavy carbonized slurry into powder and mother liquor.

According to another aspect of the present invention, in the method of producing sodium bicarbonate using the soda bicarbonate production apparatus, the combustion exhaust gas containing carbon dioxide (CO ₂ ) is converted into a gas-liquid bubble tower using a first micro bubbler. Supplying the sodium carbonate solution to the inside, supplying the aqueous solution of sodium carbonate into the gas-liquid bubble tower using a second microbubbler, bicarbonation by performing a bicarbonation reaction between the aqueous solution of sodium carbonate and the combustion exhaust gas It provides a method for producing sodium bicarbonate comprising the step of preparing a soda (NaHCO ₃ ) slurry and transferring the sodium bicarbonate slurry to a dehydration process to separate it into powder and mother liquor.

According to an embodiment of the present invention, the aqueous solution of sodium carbonate may be supplied by spraying at a pressure of 1 bar to 10 bar from the top of the gas-liquid bubble tower using a second micro bubbler.

According to an embodiment of the present invention, the aqueous solution of sodium carbonate may be supplied in an amount of 5 wt% to 30 wt%.

According to an embodiment of the present invention, the combustion exhaust gas including carbon dioxide may be supplied by spraying the gas-liquid bubble tower from the bottom to the top at a pressure of 1 bar to 10 bar using a first micro bubbler. .

According to an embodiment of the present invention, the combustion exhaust gas including carbon dioxide may be supplied at 0.1 m/s to 1.0 m/s.

According to an embodiment of the present invention, the step of preparing the sodium bicarbonate (NaHCO ₃ ) slurry may be manufactured by operating a gas-liquid bubble tower at a temperature of 30°C to 60°C.

According to an embodiment of the present invention, the dehydration process may be separating into powder and mother liquor using a vibration separation membrane.

According to an embodiment of the present invention, the powder separated by using the vibration separation membrane may be transferred to a drying process with a sodium bicarbonate slurry, and the mother liquor may be recycled by moving to a storage unit containing an aqueous sodium carbonate solution.

According to an embodiment of the present invention, the drying process may be to maintain the drying process at 40° C. to 70° C. in order to obtain a solid powder by drying the powder.

The effect of the apparatus for producing sodium bicarbonate and the method for producing the same according to the present invention will be described as follows.

By utilizing the discharged exhaust gas and the aqueous solution of sodium carbonate generated in the production process of caprolactam, sodium bicarbonate with high commercial value can be produced, and the produced sodium bicarbonate can be used in various industries such as feed additives and detergents.

1 is a schematic diagram showing a production process flow of sodium bicarbonate according to an embodiment of the present invention.
2 is a simplified diagram of an apparatus for producing sodium bicarbonate according to an embodiment of the present invention.

Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but identical or similar elements are denoted by the same reference numerals regardless of reference numerals, and redundant descriptions thereof will be omitted. In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all modifications included in the spirit and scope of the present invention It should be understood to include equivalents or substitutes.

Terms including ordinal numbers, such as first and second, may be used to describe various elements, but the elements are not limited by the terms. These terms are used only for the purpose of distinguishing one component from another component.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In the present application, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

The reaction formula of the sodium bicarbonate reaction in which carbon dioxide and sodium carbonate react to produce sodium bicarbonate is shown in Scheme 1 below.

[Scheme 1]

Na ₂ CO ₃ +CO ₂ +H ₂ O = ₂ NaHCO ₃

As shown in Scheme 1, 1 mole of sodium carbonate reacts with 1 mole of carbon dioxide and water to generate 2 moles of sodium bicarbonate.In the reaction formula, when considering the molecular weight of raw materials and products, 1 ton of sodium carbonate is injected. Through this, about 1.6 tons of sodium bicarbonate can be produced. In this regard, generally, an apparatus for producing sodium bicarbonate using carbon dioxide and soda carbonate is known to produce sodium bicarbonate through a sodium carbonate dissolution process, a carbon dioxide capture process, and a carbonation reaction process. At this time, the carbon dioxide used for the reaction uses high-purity carbon dioxide secured through the capture process, and it is known that a lot of cost is required to install and operate the plant for the carbon dioxide capture process.

Accordingly, in the present invention, it is intended to provide an apparatus for producing sodium bicarbonate having low cost and high efficiency.

The apparatus for producing sodium bicarbonate according to this embodiment is a byproduct of carbon dioxide (CO ₂ ) contained in exhaust gas discharged from thermal power plants, cement and petrochemical plants, and sodium carbonate (Na ₂ CO ₃ ) aqueous solution generated in the production process of caprolactam. It relates to an apparatus for producing sodium bicarbonate (NaHCO ₃ ) through a chemical reaction of. More specifically, in the apparatus for producing sodium bicarbonate according to the present embodiment, the exhaust gas emitted from the power plant is directly absorbed without a separate carbon dioxide capture process or treatment process, and the exhaust gas containing carbon dioxide and sodium carbonate generated in the production process of caprolactam (Na ₂ CO ₃ ) An aqueous solution by-product is produced using the bicarbonate soda production apparatus 200 without a separate treatment.

Hereinafter, the apparatus and method for producing sodium bicarbonate of the present invention will be described in detail.

1 is a schematic diagram showing a production process flow of sodium bicarbonate according to an embodiment of the present invention. As shown in FIG. 1, looking at the production process flow of bicarbonate soda of the bicarbonate soda production apparatus 100, exhaust gas including carbon dioxide generated from the external plant 110 is supplied to the bicarbonate slurry production reactor 120 do. In addition, an aqueous sodium carbonate solution is supplied from the soda carbonate dissolution reactor 130 containing the aqueous sodium carbonate solution generated in the production process of caprolactam to the slurry preparation reactor 120. Thereafter, the sodium bicarbonate slurry prepared through the bicarbonate reaction in the slurry preparation reactor 120 moves to the dehydration reactor 140 to separate the sodium bicarbonate and the filtrate to prepare sodium bicarbonate.

2 is a simplified diagram of an apparatus for producing sodium bicarbonate according to an embodiment of the present invention, and a detailed description of an apparatus for producing sodium bicarbonate and a method for producing sodium bicarbonate according to a production process flow.

As shown in FIG. 2, the bicarbonate soda production apparatus 200 includes a combustion exhaust gas supply unit 210, a sodium carbonate aqueous solution supply unit 230, a gas-liquid bubble tower 220 for preparing a bicarbonate slurry, and dehydration. Includes part 240.

First, the combustion exhaust gas supply unit 210 includes a combustion exhaust gas input line 211, a first high pressure compressor 212, a first inlet 213 and a first micro bubbler 214.

Specifically, the combustion exhaust gas supply unit 210 is supplied with the combustion exhaust gas through the first inlet 213 along the combustion exhaust gas input line 211 to the gas-liquid bubble tower 220, and the combustion exhaust gas input line ( The combustion exhaust gas supplied along 211) is in a high-pressure state through the first high-pressure compressor 212, and the high-pressure combustion exhaust gas is supplied into the gas-liquid bubble tower 220.

At this time, in order to improve the dispersibility of the combustion exhaust gas supplied into the gas-liquid bubble tower 220, the gas-liquid bubble tower 220 is introduced into the gas-liquid bubble tower 220 using the first microbubbler 214, which is a disperser in the form of a high pressure nozzle. By dispersing and supplying, the combustion exhaust gas may be supplied at a high pressure of 1 bar to 10 bar.

In addition, the combustion exhaust gas supplied to the gas-liquid bubble tower 220 is a low concentration as it supplies carbon dioxide discharged from a chemical plant or a power plant without a separate collection process. Specifically, the concentration of the combustion exhaust gas may be 10 vol% to 15 vol%.

In addition, the combustion exhaust gas is characterized in that it is supplied to the inside of the gas-liquid bubble tower 220 at a linear speed of 0.1m/s to 1.0m/s.

The soda carbonate aqueous solution supply unit 230 includes a soda carbonate aqueous solution storage device 231, a second high pressure compressor 232, a second inlet 233, and a second micro bubbler 234.

In detail, the aqueous sodium carbonate solution is supplied to the inside of the gas-liquid bubble tower 220 through the second inlet 233, and the aqueous sodium carbonate solution contained in the storage device 231 is a second high-pressure compressor. It is characterized in that the high-pressure state is achieved through the lasher 232, and a high-pressure sodium carbonate aqueous solution is supplied to the inside of the gas-liquid bubble column 220. At this time, in order to improve the dispersibility of the high-pressure sodium carbonate aqueous solution supplied into the gas-liquid bubble tower 220, the gas-liquid bubble tower 220 is used by using the second microbubbler 234, which is a high-pressure nozzle type disperser. ) To be distributed and supplied inside, the aqueous solution of sodium carbonate may be supplied at a high pressure of 1 bar to 10 bar.

In addition, the aqueous solution of sodium carbonate supplied to the gas-liquid bubble tower 220 uses an aqueous solution of sodium carbonate produced as a by-product in the caprolactam process, and in detail, the concentration of the aqueous sodium carbonate solution may be 5 wt% to 30 wt%. have. In detail, the concentration of the aqueous sodium carbonate solution may be 10 wt% to 20 wt%.

In addition, the aqueous solution of sodium carbonate is characterized in that it is supplied to the inside of the gas-liquid bubble tower 220 at a flow rate of 10ml/min to 60ml/min.

In the gas-liquid bubble tower 220, the combustion exhaust gas and the aqueous sodium carbonate solution supplied from the combustion exhaust gas supply unit 210 and the sodium carbonate aqueous solution supply unit 230 undergo a bicarbonate reaction to produce sodium bicarbonate.

The gas-liquid bubble tower 220 is a principle in which a flow is induced in the reactor by the flow of a fluid injected at high pressure without any internal components inside the tower, thereby activating a chemical reaction. In order to increase production efficiency, the gas-liquid The diameter (D) of the bubble tower is preferably set such that the linear velocity of the combustion exhaust gas introduced into the gas-liquid bubble tower is 0.1 m/s to 1.0 m/s.

In addition, the height (H) of the gas-liquid bubble tower is the ratio of the diameter to the height of the gas-liquid bubble tower 220 (H/D, H: height of the gas-liquid bubble tower, D: gas- It is preferable that the diameter of the liquid bubble tower) has a range of 5 to 20 times.

For example, when the H/D of the gas-liquid bubble tower 220 is 20 times or more, the mixing efficiency of the slurry is lowered, and when the H/D of the gas-liquid bubble tower 220 is 5 or less, the fluid in the slurry The separation efficiency of the solid component may be lowered by mixing, and the final yield may be lowered.

In addition, the operating temperature of the gas-liquid bubble tower 220 may be 30 ℃ to 60 ℃.

For example, when the operating temperature is less than 30°C, the solubility of solid sodium carbonate is lowered, so that a part of the solid sodium carbonate is precipitated, so that stable operation may be difficult.

In addition, a combustion exhaust gas supply unit 210 is disposed below the gas-liquid bubble tower 220, and a sodium carbonate aqueous solution supply unit 230 is disposed above the gas-liquid bubble tower 220. Since the combustion exhaust gas supply unit 210 is located at the bottom and the sodium carbonate aqueous solution supply unit 230 is located at the top, the combustion exhaust gas and the aqueous sodium carbonate solution are mixed to maximize the residence time in the gas-liquid bubble tower 220 It is characterized in that to be.

At this time, when the residence time is maximized, the particle size of the final product (sodium bicarbonate) can be produced at an industrially usable level due to the increase in the reaction time for bicarbonate in the process.

The apparatus for producing sodium bicarbonate according to the present invention may be introduced into a dehydration and drying process in order to utilize the sodium bicarbonate slurry produced in a continuous reaction process in a dried powder form. Since the solid content of the prepared sodium bicarbonate slurry is usually 10 to 30 wt%, an effective dehydration process is absolutely necessary.

To this end, the apparatus for producing sodium bicarbonate according to the present invention may constitute a vibration-type dehydration process in order to effectively dehydrate the sodium bicarbonate. In general, a belt-type dehydration process is often used for the dehydration of a slurry containing solid particles, but the average size of the sodium bicarbonate slurry prepared by using the soda bicarbonate production apparatus according to the present invention is 10㎛ to 20㎛. As it is small, it may be unreasonable to apply the belt-type dehydration process.

Accordingly, the dehydration unit 240 according to the present invention is characterized in that it includes a discharge pipe 241, a pump 242, and a collecting device 243. In addition, the dehydration unit 240 may further include a separator, a vibration generating unit, and a drying unit. The dehydration unit 240 is disposed outside the gas-liquid bubble tower 220 and is characterized in that it receives and dehydrates sodium bicarbonate generated by a bicarbonate reaction between the combustion exhaust gas and the aqueous sodium carbonate solution.

First, the discharge pipe 241 may be formed in the form of a'b' shape, and the vertical pipe may extend along the longitudinal direction of the gas-liquid bubble tower 220, and the bicarbonate produced through the vertical pipe is configured to fall. Can be. In addition, the horizontal pipe of the discharge pipe 241 is capable of being separated and dried while the sodium bicarbonate dropped from the gas-liquid bubble tower 220 moves, and the other end may be connected to the collecting device 243.

In addition, the pump 242 may be disposed in a part of the horizontal pipe of the discharge pipe 241. The pump 242 may be configured to flow bicarbonate soda moving to the separation membrane through the discharge pipe 241.

For example, the pump 242 may be disposed on the horizontal observation side, and the separator and the vibration generator may be disposed at the rear end of the pump 242 based on the flow direction in which the bicarbonate soda flows to the discharge pipe 241.

The separation membrane may be formed to correspond to the inner periphery of the discharge pipe 241 for discharging the bicarbonate to the outside of the gas-liquid bubble tower 220, and micropores may be formed on the surface. The size of the micropores may be formed to allow penetration of sodium bicarbonate, for example, the size of the micropores may be 10 μm to 20 μm.

The vibration generating unit causes vibration in the separation membrane and may be connected to the separation membrane and disposed outside the discharge pipe 241. The vibration generator may be disposed to prevent the micropores from being blocked by sodium bicarbonate, and when the differential pressure of the discharge pipe 241 increases by 10% or more than a normal time, the vibration generator may be operated. For example, the separation membrane may be vibrated by the frequency applied to the vibration generating unit, and may be configured to prevent micropores of the separation membrane from being blocked by small particles due to vibration of the separation membrane.

The sodium bicarbonate slurry separated by using the separator and the vibration generator is separated into sodium bicarbonate powder and a mother liquor. At this time, the separated sodium bicarbonate slurry is moved to a drying unit, and the mother liquor is moved to a storage device 231 containing a sodium carbonate aqueous solution and recycled.

Most of the water containing residual impurities contained in the sodium bicarbonate slurry is firstly removed by passing through the separation membrane. At this time, the sodium bicarbonate slurry powder that has passed through the separation membrane may be composed of a mixture of wet powder and powder, and the moisture content of the moisture that has passed through the separation membrane may be about 10 wt% to 30 wt%.

Accordingly, in order to completely dry the residual moisture remaining in the sodium bicarbonate slurry that has passed through the separation membrane, it is dried through a drying unit. By drying the residual moisture of the sodium bicarbonate slurry from which most of the moisture has been removed, energy consumption required for drying can be significantly reduced.

Specifically, the drying unit is configured to dry the sodium bicarbonate that has passed through the separation membrane, is disposed on the outer surface of the discharge pipe 241, a plurality of through holes are formed in the discharge pipe 241 close to the drying unit, the discharge pipe 241 By increasing the temperature of the sodium bicarbonate flowing through, residual moisture can be removed. In this case, the drying unit may include a dryer and a heater.

For example, the drying unit may be dried with medium temperature air introduced from the bottom of the dryer. In detail, the drying temperature may be 40°C to 70°C.

Sodium bicarbonate, which has been dried through the drying unit, may be collected by the collecting device 243. Sodium bicarbonate collected by the collecting device 243 can be used to remove various impurities (chlorine, nitrogen oxides, sulfur oxides, etc.) included in the exhaust gas generated by the industry.

The residual gas discharge unit 250 is disposed above the gas-liquid bubble tower 220 based on a direction perpendicular to the ground, and may discharge residual gas excluding combustion exhaust gas and aqueous sodium carbonate solution to the outside.

Specifically, the residual gas discharge unit 250 may include a net 251 and a residual gas discharge port 251 along the inner circumference of the gas-liquid bubble tower 220. The net 251 may be disposed below the residual gas outlet 251, and micropores may be formed on the surface. At this time, the micropores on the surface of the net 251 may be formed in a size that does not allow the penetration of the manufactured sodium bicarbonate.

For example, the combustion exhaust gas injected upward and the aqueous sodium carbonate solution injected downward react, and the residual gas is discharged to the residual gas outlet 251, thereby reacting the carbon dioxide of the combustion exhaust gas with the aqueous sodium carbonate solution. A flow field may be formed in the liquid bubble tower 220, and sodium bicarbonate may be formed in a slurry form by a chemical reaction, and the sodium bicarbonate slurry may be transferred to the dehydration unit 240.

Hereinafter, the present invention will be described in detail through examples and experimental examples. However, the following examples and experimental examples are merely illustrative of the present invention, and the present invention is not limited by the following examples and experimental examples.

Example 1.

The combustion exhaust gas is introduced at a flow rate of 25 L/min through the gas input line at the bottom of the bubble tower reactor. At this time, the flow rate of the flue gas falls within the range of operating conditions for optimal performance in the experimental device. The concentration of carbon dioxide based on the daily carbon dioxide treatment amount of ₁₀ kgCO ₂ is a condition for simulating the exhaust gas conditions of a coal-fired power plant (carbon dioxide concentration: 13 vol% to 15 vol%), and the carbon dioxide concentration contained in the input combustion exhaust gas is about 13 vol% to 15 vol%. The gas-liquid bubble tower has a height of 1,200 mm and a diameter of 80 mm. The temperature, concentration, and amount of the aqueous sodium carbonate solution to be added are 60°C, 30wt%, and 45ml/min, respectively. The concentration of the aqueous soda carbonate solution is similar to the amount of soda carbonate that can be dissolved at an input temperature of 60°C.

The aqueous solution of sodium carbonate in this example uses an aqueous solution of soda carbonate produced as a by-product in the caprolactam process, and the concentration of the sodium carbonate is 13 wt% to 15 wt%. The concentration corresponds to the average concentration of sodium carbonate in the caprolactam process by-product.

A measuring device was installed inside the gas-liquid bubble tower to measure temperature, pressure, conductivity, and pH, so that various changes in conditions occurring during continuous operation could be measured. Sodium bicarbonate produced through the carbonation reaction is then subjected to dehydration and drying processes to obtain a final powdery powder. When drying, the temperature is set to 40℃ so that the thermal decomposition of sodium bicarbonate (2NaHCO ₃ → Na ₂ CO ₃ + H ₂ O +CO ₂ ) is minimized. In Example 1, a continuous operation was performed for about 3 hours, and the operation results and the purity and particle diameter of the prepared sodium bicarbonate are shown in Tables 1 and 2.

Example 2.

In Example 1, the main results carried out in the same manner as in Example 1, except that the flow rate of the aqueous solution of sodium carbonate added to the top of the bubble tower reactor was 55 ml/min, are shown in Tables 1 and 2.

Example 3.

In Example 1, the main results carried out in the same manner as in Example 1, except that the height of the gas-liquid bubble tower reactor was 1,000 mm, are shown in Tables 1 and 2.

Comparative Example 1.

In Example 1, the main results are shown in Tables 1 and 2 in the same manner as in Example 1, except for the method of dissolving industrial sodium carbonate (purity> 98%) and constituting sodium carbonate as the main raw material.

Remark Reactor
Height(mm) Soda carbonate input Carbon dioxide conversion rate
(Or collection rate) Remark Parts by weight Input amount (ml/min) Example 1 1,200 30 45 58~61% Caprolactam
production process
by-product Example 2 1,200 30 55 59~62% Example 3 1,000 30 45 49~53% Comparative Example 1 1,200 30 45 61-62% Industrial purchase

Remark Sodium bicarbonate purity (%) Sodium bicarbonate particle size 355㎛ or more 355㎛ or less Example 1 97 <1% > 99% Example 2 96 <1% > 99% Example 3 97 <1% > 99% Comparative Example 1 98 <1% > 99%

In the case of Example 1, the carbon dioxide capture rate (conversion rate) was kept constant over 55%, and as a result of analysis of the components of the powder obtained through this, the purity was at the level of about 97%, and it was confirmed that there was no significant difference from the purity of the commercially available product. , It was confirmed that a particle diameter of less than 355 μm was 99% or more, and a considerable fine powder was generated.

In Example 2, the height of the reactor was the same and the input amount of the aqueous sodium carbonate solution was changed, and there was no significant difference in the conversion rate of carbon dioxide from that of Example 1.

In the case of Example 3, compared to Example 1, the height of the gas-liquid bubble tower was reduced by 200 mm, and it was confirmed that the carbon dioxide conversion rate was reduced by 5% to 10%. Through this, it was confirmed that the design of an optimal gas-liquid bubble tower manufacturing apparatus is important for effective heavy carbonation reaction.

In addition, when comparing Example 1 and Comparative Example 1, it was confirmed that even when industrial sodium carbonate was used, the carbon dioxide conversion rate was similar to that of Example 1. Through this, it can be confirmed that excellent sodium bicarbonate can be prepared using an aqueous solution of sodium carbonate generated in the combustion flue gas and caprolactam production process.

Sodium bicarbonate manufactured using the apparatus for producing sodium bicarbonate according to the present invention has a small particle size, and thus reactivity with pollutants in exhaust gas is improved, and impurities can be more effectively removed.

In addition, by using exhaust gas generated from coal-fired power plants, cement and petrochemical plants, etc., it is possible to reduce carbon dioxide, which is a greenhouse gas, by producing sodium bicarbonate, which is commercially valuable, and the generated bicarbonate is used to refine exhaust gas, It can be used in various industries such as feed additives and detergents.

In this specification, only a few examples of various embodiments performed by the present inventors will be described, but the technical idea of the present invention is not limited thereto or is not limited thereto, and may be modified and variously implemented by those skilled in the art.

100: bicarbonate soda production apparatus
110: external plant
120: slurry preparation reactor
130: sodium carbonate dissolution reactor
140: dehydration reactor
200: bicarbonate soda production apparatus
210: combustion exhaust gas supply unit, 211: combustion exhaust gas input line, 212: first high pressure compressor, 213: first inlet, 214: first micro bubbler
220: vapor-liquid bubble tower
230: Soda carbonate aqueous solution supply unit, 231: Soda carbonate aqueous solution storage device, 232: second high pressure compressor, 233: second inlet, 234: second microbubbler
240: dehydration unit, 241: discharge pipe, 242: pump, 243: collection device

Claims (14)

delete delete delete delete delete delete delete delete delete A sodium carbonate aqueous solution supply unit for supplying an aqueous sodium carbonate solution;
A combustion exhaust gas supply unit for supplying combustion exhaust gas including carbon dioxide (CO ₂ );
A gas-liquid bubble tower in which the aqueous solution of sodium carbonate and the combustion exhaust gas undergo a bicarbonate reaction to prepare a slurry of sodium bicarbonate; And
Including; a dehydration unit for separating the powder and mother liquor by transferring the sodium bicarbonate slurry,
The combustion exhaust gas supply unit includes a first high pressure compressor,
The gas-liquid bubble tower includes a micro bubbler for supplying the aqueous solution of sodium carbonate and the combustion exhaust gas,
The micro bubbler includes a first micro bubbler for supplying the combustion exhaust gas,
The first micro bubbler is disposed under the gas-liquid bubble tower,
In the combustion exhaust gas, combustion exhaust gas in a high pressure state is formed through the first high pressure compressor,
The pressure of the combustion exhaust gas in the high-pressure state is 1 bar to 10 bar,
The aqueous solution of soda carbonate supplies a by-product generated from the production process of caprolactam (C ₆ H ₁₁ NO),
Soda bicarbonate production device. delete The method of claim 10,
The micro bubbler includes a second micro bubbler for supplying the aqueous solution of sodium carbonate,
The second micro bubbler is located above the gas-liquid bubble tower,
To supply the sodium carbonate aqueous solution by spraying at a pressure of 1 bar to 10 bar,
Soda bicarbonate production device. delete The method of claim 10,
The dehydration unit further comprises a vibration separation membrane for separating the prepared heavy carbonized slurry into powder and mother liquor.
Soda bicarbonate production device.

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