KR101875290B1 - Method for separating carbon dioxide and apparatus for separating carbon dioxide - Google Patents

Abstract

The present invention relates to a carbon dioxide separation method in a flue gas and a carbon dioxide separation apparatus using the same. More particularly, the present invention relates to a carbon dioxide separation method using a flue gas, comprising: a pressurization dissolution step of pressurizing a flue gas to dissolve carbon dioxide in pure water; A separation step of separating the pure water in which the carbon dioxide is dissolved; A depressurizing step of depressurizing the pure water in which the carbon dioxide is dissolved; A degassing step of degassing the carbon dioxide from the decompressed pure water; And a collecting step of collecting the degassed carbon dioxide; And a separation apparatus using the same.
The present invention can separate and collect carbon dioxide in the flue gas in a simple process using the difference in solubility of the gas depending on the pressure.

Description

METHOD FOR SEPARATING CARBON DIOXIDE AND APPARATUS FOR SEPARATING CARBON DIOXIDE BACKGROUND OF THE INVENTION [0001]

The present invention relates to a carbon dioxide separation method in flue gas and a carbon dioxide separation apparatus using the same.

Flue gas emitted from a boiler of a thermal power plant, a steel mill, a cement plant, or an industrial plant using fossil fuels is converted into carbon dioxide and reduced nitrogen such as SO ₂ , NO x, NH ₃ and HCN, which are harmful gases And emissions of flue gases have a negative impact on the environment because they contain a large amount of carbon dioxide that contributes to global warming and atmospheric change. Carbon dioxide should be separated from the flue gas to prevent or reduce the emission of carbon dioxide.

Various methods for separating or reducing carbon dioxide from flue gas have been proposed. For example, the carbon dioxide separation process consists of separation, compression, storage, and transfer phases, which account for more than half of the total cost in the separation phase. In order to minimize the operating cost of the CO2 separation process, the energy required to regenerate the adsorbent should be reduced. The separation step of carbon dioxide is composed of absorption, adsorption and membrane separation. Absorption is carried out at a low temperature and a high pressure with an aqueous solution of an alkanolamine such as monoethanolamine (MEA), diethanolamine (DEA) Zeolite, activated carbon, metal carbonate and the like are applied as dry adsorbents. However, the use of such adsorbents is not preferable because of low selectivity of carbon dioxide, high facility cost and operation cost .

The present invention is directed to a method for separating and collecting carbon dioxide in a flue gas by a simple process using the difference in solubility according to the pressure of the gas.

The present invention also relates to a carbon dioxide separation apparatus using the carbon dioxide separation method in the flue gas.

One aspect of the present invention is a method for producing carbon dioxide, comprising: a pressurization dissolution step of pressurizing a flue gas to dissolve carbon dioxide in pure water; A separation step of separating the pure water in which the carbon dioxide is dissolved; A depressurizing step of depressurizing the pure water in which the carbon dioxide is dissolved; A degassing step of degassing the carbon dioxide from the decompressed pure water; And a collecting step of collecting the degassed carbon dioxide; To a carbon dioxide separation method.

According to an embodiment of the present invention, the pressurizing and melting step includes the steps of: injecting the pure water into the feed tank; Injecting said pure water into said chamber at a water pressure between 3 and 20 bar; And injecting the flue gas into pure water at a partial pressure of 3 to 20 bar to dissolve the carbon dioxide; . ≪ / RTI >

According to an embodiment of the present invention, the step of injecting the pure water into the chamber and the step of dissolving the carbon dioxide may be performed sequentially or simultaneously.

According to an embodiment of the present invention, the pressurizing and melting step includes the steps of: injecting the pure water into the feed tank; And mixing said flue gas at a water pressure of 3 to 20 bar with said flue gas at a pressure of 3 to 20 bar in a single feed tube and injecting into said chamber; . ≪ / RTI >

According to an embodiment of the present invention, the pressurizing and melting step includes the steps of: injecting the pure water into the feed tank; Maintaining the water pressure of the pure water at 3 to 20 bar and bubbling the flue gas into the pure water to dissolve the carbon dioxide; And purging the flue gas with pure water bubbled into the chamber at a water pressure of 3 to 20 bar. . ≪ / RTI >

According to one embodiment of the present invention, the step of bubbling and dissolving carbon dioxide may bubble by introducing the flue gas of 3 to 20 bar into the feed tank.

According to one embodiment of the present invention, the separating step may separate pure water in which the gas and carbon dioxide dissolved in the pure water are dissolved.

According to one embodiment of the present invention, the pressurizing and melting step may use a gas and a flue gas which are not dissolved in the pure water separated in the separation step.

According to an embodiment of the present invention, in the depressurizing step, the pure water in which the carbon dioxide is dissolved may be decompressed to atmospheric pressure by passing the pure water through the separator or by regulating the pressure control valve.

According to an embodiment of the present invention, the separation membrane is a separation membrane that can operate at a partial pressure of 3 to 20 bar, and the separation membrane may include at least one selected from the group consisting of a microfiltration membrane, an ultrafiltration membrane, have.

According to an embodiment of the present invention, the degassing step may include degassing the carbon dioxide in the decompressed pure water, applying the deaerated pure water to the depressurization step and the degassing step after the degassing step, Can be repeated more than once.

According to an embodiment of the present invention, the pure water from which the carbon dioxide has been degassed after the degassing step may be injected into the feed tank and applied to the pressure melting step.

According to an embodiment of the present invention, the step of injecting the flue gas may be injected at a partial pressure of 3 to 20 bar.

According to one embodiment of the present invention, the pressurization dissolution step may enhance pressurization dissolution of the carbon dioxide by irradiating infrared rays.

Another aspect of the present invention relates to a feed tank in which pure water is filled; Liquid supply means for injecting pure water discharged from the feed tank into the chamber at a certain water pressure; A bypass line for regulating a flow rate of pure water discharged from the feed tank; Gas supplying means for injecting the flue gas into the chamber at a constant partial pressure; A chamber in which the carbon dioxide of the flue gas is dissolved in the pure water and the undissolved gas is collected in the upper layer; Gas discharge means for discharging gas in the upper layer in the chamber; Liquid discharging means for discharging pure water from the chamber; A decompression unit for decompressing the discharged pure water; A deaerator for degassing the carbon dioxide in the decompressed pure water; And a carbon dioxide collecting unit for collecting the degassed carbon dioxide; To a carbon dioxide separation device.

According to one embodiment of the present invention, the feed tank includes: a pressurizing means for pressurizing the pure water with a constant pressure; And a bubbler for injecting flue gas into the pure water; As shown in FIG.

According to an embodiment of the present invention, a single supply pipe for mixing the flue gas of constant partial pressure and the pure water of constant water pressure discharged from the feed tank into the chamber; As shown in FIG.

According to an embodiment of the present invention, an infrared lamp further includes an infrared lamp, and the infrared lamp may irradiate infrared rays to at least one of the feed tank, the chamber, and the single supply pipe.

According to an embodiment of the present invention, the pressure-reducing unit may include a separator for filtering and discharging the discharged pure water, a pressure regulating valve, or both.

According to an embodiment of the present invention, the apparatus may further include a liquid circulating unit for supplying the pure water deaerated in the degassing unit to at least one of the feed tank, the chamber, the single feed pipe, and the pressure reducing unit.

The present invention can separate and collect carbon dioxide in a simple process using the difference in solubility between the carbon dioxide contained in the flue gas and the pressure of the other gas.

The present invention can decompose carbon dioxide by using a solvent without using a large amount of adsorbent, reuse the solvent after carbon dioxide separation, or repeat the carbon dioxide separation process using a separated gas without dissolving in the solvent, The economical efficiency and process efficiency of the process can be improved.

Fig. 1 illustrates, by way of example, a flow chart of a carbon dioxide separation method according to an embodiment of the present invention.
Fig. 2 illustrates an exemplary flow chart of a carbon dioxide separation method according to another embodiment of the present invention.
FIG. 3 is a flow chart illustrating a method of separating carbon dioxide according to the present invention, according to another embodiment of the present invention.
4 is a flow chart of a method for separating carbon dioxide according to the present invention, according to another embodiment of the present invention.
5 illustrates an exemplary carbon dioxide separation apparatus according to an embodiment of the present invention.
FIG. 6 illustrates an exemplary carbon dioxide separation apparatus according to another embodiment of the present invention.
FIG. 7 is a schematic view illustrating an apparatus for separating carbon dioxide according to another embodiment of the present invention.
FIG. 8 is a view illustrating an example of a carbon dioxide separation apparatus according to another embodiment of the present invention.
FIG. 9 is a view illustrating an example of a carbon dioxide separation apparatus according to another embodiment of the present invention.
FIG. 10 is a view showing an example of a carbon dioxide separation apparatus according to another embodiment of the present invention.
FIG. 11 is a view illustrating an example of a carbon dioxide separation apparatus according to another embodiment of the present invention.
FIG. 12 is a view showing an example of a carbon dioxide separation apparatus according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, 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. Also, terminologies used herein are terms used to properly represent preferred embodiments of the present invention, which may vary depending on the user, intent of the operator, or custom in the field to which the present invention belongs. Therefore, the definitions of these terms should be based on the contents throughout this specification. Like reference symbols in the drawings denote like elements.

The present invention relates to a carbon dioxide separation method and, in accordance with an embodiment of the present invention, carbon dioxide in a flue gas is dissolved in a solvent by using a difference in solubility of a gas according to pressure, and carbon dioxide is separated And collect it.

Referring to FIG. 1, a method of separating carbon dioxide according to an embodiment of the present invention will now be described with reference to FIG. 1. Referring to FIG. 1, the carbon dioxide separation method includes a pressurizing and melting step S100; Separation step S200; Depressurization step (S300); Degassing step (S400); And a collecting step S500.

According to one embodiment of the present invention, the pressurizing and dissolving step (SlOO) is a step of pressurizing and dissolving carbon dioxide in a flue gas in a pressurized solvent, for example, by supplying flue gas into a pressurized solvent It is possible to dissolve carbon dioxide by injection at a constant partial pressure.

For example, the solvent is a solvent capable of dissolving carbon dioxide, for example, an alcohol having 1 to 4 carbon atoms, pure water, or both. Preferably, it may be pure.

2, a carbon dioxide separation method according to an embodiment of the present invention will be described with reference to FIG. 2. FIG. 2 is a flowchart illustrating a carbon dioxide separation method according to an embodiment of the present invention. (S110a); Injecting a solvent into the chamber (S120a); And injecting the flue gas into the solvent in the chamber to dissolve the carbon dioxide (S130a); (S100), which includes a pressurizing step (S100).

In an embodiment of the present invention, the step (S110a) of injecting the solvent into the feed tank is carried out by filling the feed tank with a solvent and heating at a temperature of 0 ° C to 30 ° C; A temperature of from 5 캜 to 25 캜; Alternatively, the solvent can be maintained at room temperature.

For example, at least a portion of the solvent may be the re-use of the solvent used in the process for separating carbon dioxide according to the present invention.

In one embodiment of the invention, the step of injecting the solvent into the chamber (S120a) comprises: atmospheric pressure, 3 to 20 bar; 3 to 10 bar pressure; 4 to 7 bar pressure; Or 4 to 6 bar, and the solubility of carbon dioxide to the solvent may be increased as the water pressure is increased. The solvent may also be injected into the chamber at a controlled flow rate according to a constant flow rate or process, and the solvent may be maintained at or above the water pressure at the time of injection in the chamber to increase the solubility of the carbon dioxide. In addition to operating at 3 to 10 bar, the present invention also includes operability at high pressures. For example, in areas where the CO2 separation method is applied, when a high-pressure gas mixture is provided (eg, a pre-combustion gas), a high-pressure solvent transfer pump should be used to remove carbon dioxide, (For example, a seawater desalination apparatus in which the pressure is recovered from the concentrated water discarded at high pressure and turned to the inflow water, and the high-pressure concentrated water is converted to the concentrated water at low pressure (atmospheric pressure)).

For example, injecting the solvent into the chamber (S120a) may be performed at a temperature between 0 ° C and 30 ° C; 5 ° C to 25 ° C temperature; Alternatively, the solvent can be maintained at room temperature.

For example, injecting a solvent into the chamber (S120a) may include: introducing a solvent into the chamber at an atmospheric pressure of 3 to 20 bar; 3 to 10 bar pressure; 4 to 7 bar pressure; Or 4 to 6 bar water pressure.

In one embodiment of the present invention, the step (S130a) of injecting flue gas into a solvent in the chamber to dissolve carbon dioxide (S130a) comprises: 3 to 20 (bar); 3 to 10 (bar) partial pressure; 4 to 7 (bar) partial pressure; Or 4 to 6 (bar) partial pressures to pressurize and dissolve carbon dioxide in the flue gas. Since this pressurized solution mixes the pressurized solvent and the flue gas at atmospheric pressure or higher, the carbon dioxide having high solubility is dissolved in the solvent due to the difference in solubility according to the pressure of the gas in the flue gas, and the dissolved gas (for example, O ₂ , N _2, etc., hereinafter referred to as a gas) is collected in the upper layer in the chamber.

For example, the step of dissolving carbon dioxide (S130a) is a step in which, in the step of separating carbon dioxide according to the present invention, a gas which is not dissolved in the solvent, for example, a gas which is not dissolved in the solvent in the chamber, After discharging, it can be injected alone or mixed with the flue gas into the chamber.

For example, the step of injecting the solvent into the chamber (S120a) and the step of dissolving carbon dioxide (S130a) are performed by sequentially injecting the solvent into the chamber (S120a) and then the step of dissolving carbon dioxide (S130a) The step of injecting the solvent into the chamber (S120a) and the step of dissolving the carbon dioxide (S130a) may be performed at the same time in order to make the mixing of the flue gas and the solvent and the dissolution of the carbon dioxide better.

3 is a flowchart illustrating a method of separating carbon dioxide according to an embodiment of the present invention. Referring to FIG. 3, the method for separating carbon dioxide includes the steps of injecting a solvent into a feed tank Step S110b; And mixing the solvent and flue gas in a single feed line and injecting the mixture into the chamber (S120b); (S100), which includes a pressurizing step (S100).

In one embodiment of the present invention, the step of injecting the solvent into the feed tank (S110b) may be performed in the same manner as the step S110a mentioned in Fig.

In one embodiment of the present invention, the step (S120b) of mixing solvent and flue gas in a single feed pipe and injecting into the chamber (S120b) comprises the step of injecting flue gas of 3 to 20 bars of barometric pressure and 3 to 20 bar of flue gas into a single feed pipe And injecting the mixture into the chamber.

For example, the solvent and the flue gas may be mixed while flowing through a single feed line at the same or different pressures, and at least a portion of the carbon dioxide in the flue gas may be pressurized into a solvent in a single feed line.

For example, after being injected into the chamber, the hydraulic pressure of the solvent in the chamber may be maintained constant or higher to induce pressurized dissolution of the carbon dioxide in the solvent, and if necessary, the solvent may be stirred in the chamber have.

For example, the step of injecting (S120b) into the chamber may be carried out by supplying unmelted gas and flue gas into the single supply pipe, referred to in Fig. 2, or the gas may be injected into the chamber through a separate supply pipe have.

In accordance with another embodiment of the present invention, referring to FIG. 4, FIG. 4 illustrates a flow diagram of a method for separating carbon dioxide according to the present invention. 4, the carbon dioxide separation method includes: injecting a solvent into a feed tank (S110c); Bubbling the flue gas into the solvent to dissolve the carbon dioxide (S120c); And injecting a solvent into the chamber (S130c); (Step S100).

As an example of the present invention, the step of injecting the solvent into the feed tank (S110c) is the same as mentioned in step S110a of FIG.

In one embodiment of the present invention, the step (S120c) of bubbling a flue gas with a solvent to dissolve carbon dioxide is performed by pressurizing the water pressure of the solvent in the feed tank to 3 to 20 (bar) Bubbling flue gas into a solvent at a temperature of 5 to 25 占 폚 to pressurize and dissolve carbon dioxide.

For example, the flue gas may be bubbled by introducing a flue gas of 3 to 20 bar into the feed tank.

For example, the step of dissolving carbon dioxide (S120c) may be bubbled with the gas alone or the flue gas not dissolved in the solvent, as mentioned in Fig.

In one embodiment of the present invention, the step of injecting the solvent into the chamber (S130c) comprises the step of injecting the solvent in which the flue gas is bubbled in the dissolving step (S120c) under a pressure of 3 to 20 bars, And then injected into the chamber at an appropriate flow rate.

As an example of the present invention, the pressure melting step (S100) can increase the pressure dissolution of carbon dioxide by irradiating infrared rays. For example, the infrared rays may have a diameter of 3 占 퐉 or more; Or infrared (IR) from 4 [mu] m to 5 [mu] m.

For example, the infrared rays may be applied to at least one of the pressure melting step S100 mentioned in Figs. 2 to 4.

According to one embodiment of the present invention, the separation step (S200) is a step of separating the solvent in which the gas and carbon dioxide dissolved in the solvent are dissolved.

In one embodiment of the present invention, the pressure of the solvent and the partial pressure of the gas in the chamber in the separating step (S200) are maintained above the atmospheric pressure to increase the solubility of carbon dioxide in the flue gas and to remove undissolved gases, N ₂ , O _2, etc. are collected in the upper layer in the chamber. The gas and the solvent trapped in the upper layer are respectively discharged to separate the solvent in which the carbon dioxide is dissolved.

For example, the gas trapped in the upper layer may be vented to the atmosphere or used again in the separation process of carbon dioxide, as noted in FIGS. 2-4.

According to one embodiment of the present invention, the depressurization step 300 is a step of depressurizing the solvent in which the carbon dioxide is dissolved, and the carbon dioxide dissolved in the solvent by the depressurization may be deaerated by the pressure difference.

In one embodiment of the present invention, the depressurization step 300 may reduce the pressure of the solvent in which the carbon dioxide has been dissolved to atmospheric pressure (e.g., 1 atm) using a separator, a pressure control valve, or both.

For example, after the solvent in which the carbon dioxide is dissolved is subjected to the first decompression through the separation membrane, the second decompression can be performed using the pressure control valve.

For example, the separation membrane may be a separation membrane that can operate at a partial pressure of 3 to 20 bar, and the separation membrane may be composed of a single or a plurality of separation membranes.

For example, the separation membrane may include at least one selected from the group consisting of a microfiltration membrane, an ultrafiltration membrane, and a nanofiber membrane.

According to an embodiment of the present invention, the degassing step (S400) is a step of degassing the carbon dioxide in the solvent decompressed and discharged after the decompressing step (300). For example, the carbon dioxide can be deaerated by the partial pressure difference of the decompression dissolution step (S100) and the decompression step (S300).

For example, as noted in FIGS. 2-4, the carbon dioxide depleted solvent can be reused as a solvent in the separation process of the present invention.

For example, in step S400, the carbon dioxide-depleted solvent may be degassed through a depressurization step 300, followed by depressurization step 300 and degassing step S400, More than twice; Can be repeated two to five times.

According to one embodiment of the present invention, the collecting step S500 is a step of collecting carbon dioxide which has been degassed in the degassing step S400, and one or more times depending on the number of steps of the degassing step S400. Carbon dioxide can be collected repeatedly two to five times.

According to one embodiment of the present invention, the pressurization dissolution step S100, the separation step S200, the depressurization step S300, the degassing step S400, and the collecting step S500 are performed by using a solvent (For example, the solvent discharged in the degassing step (S400)) and / or the gas (for example, the gas discharged in the separation step) may be repeatedly operated one or more times to repeatedly separate and collect carbon dioxide , The solvent can be recycled into the carbon dioxide separation process.

According to one embodiment of the present invention, a method for separating carbon dioxide according to the present invention is a method for separating a mixed gas containing carbon dioxide, for example, a mixed gas containing methane (CH ₄ ) and carbon dioxide produced in an anaerobic digestion tank, , Linz-Donawitz Gas (LDG), and Blast Furnace Gas (BFG).

The present invention relates to a carbon dioxide separation apparatus using the carbon dioxide separation method according to the present invention.

According to an embodiment of the present invention, the carbon dioxide separator according to the present invention can separate the carbon dioxide by pressurizing and dissolving the carbon dioxide by using the difference in solubility according to the pressure of the gas.

According to one embodiment of the present invention, the carbon dioxide separation apparatus according to the present invention can recycle the solvent used in the separation process and perform the repeated separation process, thereby improving the efficiency and economy of carbon dioxide separation in the flue gas .

5, the separation apparatus according to the present invention includes a feed tank 100, a chamber 200 (not shown) And a separating unit 500. The separating unit may include a supply unit for supplying the solvent and the gas at a constant pressure and a constant flow rate and a separating unit for separating the solvent and the gas from each other. And will be described more specifically with reference to Figs. 6 to 12 below. Fig.

In one embodiment of the present invention, the feed tank 100 is a feed tank filled with a solvent for dissolving carbon dioxide in the flue gas, and the feed tank controls the flue gas to a predetermined water pressure and / Can supply. The solvent is as mentioned above, preferably pure.

For example, the feed tank 100 may further include a pressurizing means and a temperature regulator (not shown in the figure) for pressurizing the solvent to a predetermined pressure.

In an embodiment of the present invention, the chamber 200 can hold the solvent in which the carbon dioxide of the flue gas is dissolved at a constant partial pressure and a constant temperature, and collect undissolved gas in the solvent as an upper layer and discharge it. The undissolved gas may be collected and discharged until a certain pressure is reached. . For example, the solvent supplied at 6-7 atmospheres may be placed underneath, and the undissolved gas may accumulate on the liquid interface to lower the liquid surface to discharge the gas.

For example, the chamber 200 may be a closed chamber. The chamber 200 may be formed by injecting a constant partial pressure flue gas into a constant-pressure solvent to pressurize the carbon dioxide, or to supply a solvent in which the carbon dioxide of the flue gas is dissolved have

For example, the gas discharged from the chamber 200 may be pressure-dissolved again in the solvent.

According to an embodiment of the present invention, the decompression unit 300 can decompress the solvent in which the carbon dioxide discharged from the chamber 200 is dissolved, and the carbon dioxide dissolved in the solvent by the decompression can be deaerated in the solvent. For example, the depressurization portion 300 can be depressurized using a separation membrane, a pressure control valve, or both.

In an embodiment of the present invention, the deaerating unit 400 may collect carbon dioxide that has been degassed from the decompressed solvent in the decompression unit 300, and then discharge the carbon dioxide to the collecting unit 500. This is because, when the carbon dioxide dissolved in the solvent is depressurized by pressurization, the solubility in the solvent is reduced by the solubility in the decompressed partial pressure, and the other is degassed. The carbon dioxide-depleted solvent may be supplied to the feed tank 100, the chamber 200, or both.

In one embodiment of the present invention, the trapping unit 500 may physically or chemically collect the carbon dioxide discharged from the deasphalting unit 400. For example, the carbon dioxide trapping may be performed by using the method used in the technical field of the present invention For example, using a carbon dioxide adsorbent or liquefying it.

6, the carbon dioxide separator according to the present invention is exemplarily shown in FIG. 6. In FIG. 6, the carbon dioxide separator includes a feed tank 100, a liquid supply means The gas discharge unit 210, the liquid discharge unit 220, the depressurization unit 300, the deaeration unit 400, And may include a collecting unit 500.

In one embodiment of the present invention, the feed tank 100 is formed by bubbling the flue gas to pressurize and dissolve carbon dioxide after the chamber 200 is filled with a solvent for supplying water at a constant water pressure or after pressurizing the solvent at a certain pressure . The solvent is as mentioned above, preferably pure.

For example, the feed tank 100 may maintain the solvent or the gas to which the flue gas is bubbled at a certain water pressure and / or temperature, and to discharge the solvent or the flue gas to which the flue gas is bubbled.

For example, the feed tank 100 may be bubbled using a bubbler, the bubbler may be a micro bubble, and the solvent in which the flue gas is bubbled may be at least 3 bar (bar); Or 6 to 7 bar atmospheric pressure.

The liquid supply means 110 may be a supply pipe for injecting the solvent discharged from the feed tank 100 (or a solvent in which the flue gas is bubbled) into the chamber 200 at a certain water pressure.

For example, the liquid supply means 110 may include a pressure pump P1, a valve 1 (V1), a flow meter L1 and a valve 2 (V2).

For example, the valve 1 (V1) is for regulating the flow rate and water pressure of the discharged solvent. The valve 1 (V1) is opened to transfer a part of the discharged solvent to the bypass line 120, 200 can be controlled.

For example, a pressurizing pump (P1, booster pump) can supply the discharged solvent into the chamber 200 under pressure and adjust the flow rate and water pressure of the discharged solvent.

For example, the flow meter (L1) can confirm the flow rate of the discharged solvent supplied into the chamber (200).

For example, the valve 2 (V2) can adjust the hydraulic pressure and the flow rate of the solvent supplied to the chamber 200 to be constant.

The bypass line 120 is for controlling the flow rate of the solvent discharged from the feed tank 100 and supplied to the chamber 200. The bypass line 120 controls the flow rate of the solvent Can be supplied. For example, the bypass line 120 opens valve 1 (V1) to deliver at least a portion of the solvent supplied to the chamber 200 to the feed tank 100 via the bypass line 120, Can be controlled.

In one example of the present invention, the gas supply means 130 may inject the flue gas into the chamber, the feed tank 100, or both at a constant partial pressure.

For example, the gas supply means 130 includes a valve 3 (V3) and a pressure gauge R1, injecting the flue gas into the chamber 200 by regulating the valve 3 (V3) The partial pressure of the flue gas can be confirmed through the flue gas R1.

For example, the valve 3 (V3) is a solenoid valve, and can control the partial pressure of the flue gas in conjunction with the valve 4 (V4) mentioned below. For example, the gas supply means 130 can supply the flue gas to the feed tank 100 at a constant pressure by adjusting the valve 3 (V3) and supply the flue gas to the feed tank 100 through the pressure gauge 3 (R3) The partial pressure of the flue gas can be confirmed.

In one embodiment of the present invention, the chamber 200 is configured to maintain or increase the hydraulic pressure of the solvent in which the carbon dioxide of the flue gas is dissolved and the partial pressure of the gas in the chamber, and collect undissolved gas in the solvent as an upper layer Is discharged through the gas discharging means (210), and the solvent in which the carbon dioxide is dissolved can be discharged through the liquid discharging means (220).

For example, the liquid discharging means 220 can regulate the pressure gauge 4 (R4) to keep the flow rate and the water pressure of the solvent supplied into or discharged from the chamber 200 constant.

For example, the chamber 200 may be injected with a constant partial pressure flue gas into a certain water pressure solvent to pressurize the carbon dioxide or to receive the carbon dioxide-dissolved solvent.

For example, the gas discharging means 210 includes a valve 4 (V4) and a pressure gauge R2 (R2), and the gas which is not dissolved in the solvent in the chamber 200 is discharged by regulating the valve 4 Alternatively, the gas may be supplied to the gas supply means 130 by adjusting the valve 4 (V4), mixed with the flue gas, or may be supplied alone to the feed tank 100 or the chamber 200. In addition, the pressure gauge 2 (R2) can check the partial pressure of the gas in the chamber 200 and adjust the discharge of the gas and the supply of the flue gas.

For example, the gas is supplied to the feed tank 100 or the chamber 200 by adjusting the valve 5 (V5) via the valve 4 (V4), and the valves 4 (V4) and 5 The partial pressure of the gas supplied to the tank 100 or the chamber 200 can be adjusted.

The pressure of the gas flowing into the feed tank 100 can be confirmed by the pressure gauge R3 and the pressure of the gas flowing into the chamber 200 by the pressure gauge R1 can be confirmed.

For example, the gas may be fed to the feed tank 100 at a constant pressure or at a suitably regulated pressure in accordance with the process, and bubbled in the feed tank 100.

For example, the valve 4 (V4) is adjusted so that the gas partial pressure (for example, 4 to 6 bar) in the chamber 100 is constant, and a solenoid valve or a pressure release valve ).

 For example, the valve 3 (V3) and the valve 4 (V4) can be adjusted so as to coincide with each other so that the values of the pressure gauge 1 (R1) and the pressure gauge 2 (R2) are the same.

The liquid discharging means 220 includes a pressure gauge R4 and discharges the solvent in which the carbon dioxide discharged from the chamber 200 is dissolved and the solvent is delivered to the decompression portion 300 . For example, by checking the pressure gauge 4 (R4), the flow rate of the solvent injected and discharged into the chamber 200 can be adjusted.

7 and 9, the pressure-reducing portion 300 is as described in FIG. 5, and FIGS. 7 to 9 illustrate the pressure-reducing portion 300 according to an embodiment of the present invention. 7, the depressurization unit 300 includes a valve 8 (V8), and the solvent in which the carbon dioxide discharged from the chamber 200 via the valve 8 (V8) is dissolved is decompressed 9, the depressurization unit 300 is depressurized through the separation membrane 310, and the depressurization unit 300 in FIG. 9 separates the depressurized solvent through the separation membrane 310 via the valve 8 (V8) The pressure can be reduced. For example, the valve 8 (V8) may be a pressure regulating valve.

5, the carbon dioxide-depleted solvent is supplied to the feed tank 100 through the liquid circulation unit 410, the chamber 500, (200) and the decompression unit (300).

For example, the liquid circulating part 410 is circulated to a predetermined pressure by the pressurizing pump P2, and the valve 6 (V6) is regulated to supply the degassed solvent to the depressurizing part 300, and the valve 7 V7 may be adjusted to supply the degassed solvent to the feed tank 100 and / or the chamber 200. For example, the degassed solvent is supplied alone by the valve 7 (V7) or mixed with the solvent discharged from the feed tank 100 and supplied to the feed tank 100 and the chamber 200 to perform continuous operation .

10, there is shown a carbon dioxide separator according to another embodiment of the present invention. In FIG. 10, the carbon dioxide separator includes: The liquid supply unit 110, the bypass line 120, the gas supply unit 130, the chamber 200, the gas discharge unit 210, the liquid discharge unit 220, the decompression unit 300 The deaerating unit 400 and the collecting unit 500 are the same as those shown in FIG. 6, and may further include a heat exchanger 600.

The energy recovery equipment 600 may be configured to remove the deaerated solvent supplied through the solvent circulation unit 410 and the solvent discharged from the feed tank 100 and flowing through the bypass line 120 Heat exchange can be performed. The heat exchanged solvent may be supplied to the feed tank 100 via the bypass line 120 or to the feed tank 100 and / or the chamber 200 via valve 7 (V7), respectively. For example, the heat exchanger 600 may be a Dual Work Exchanger Energy Recovery (Dweer) or EDI.

As an example of the present invention, the carbon dioxide separating apparatus including the heat exchanger 600 in FIG. 10 is merely an example, and the constitution of the apparatus is not limited thereto. For example, the carbon dioxide separation apparatus of Figs. 5, 8 to 9, and 11 to 12. Fig.

According to another embodiment of the present invention, referring to FIG. 11, FIG. 11 exemplifies a carbon dioxide separation apparatus according to another embodiment of the present invention. In FIG. 11, The liquid supply unit 110, the bypass line 120, the gas supply unit 130, the chamber 200, the gas discharge unit 210, the liquid discharge unit 220, the decompression unit 300 , The deaerating unit 400 and the collecting unit 500 are as described in FIG. 6 and may further include a single supply pipe 140.

In one embodiment of the present invention, the single supply pipe 140 can be supplied to the chamber 100 by mixing the flue gas supplied to the chamber 100 and the solvent. For example, the flue gas, the gas discharged from the chamber 200, or both may be supplied to the single supply pipe by adjusting the valve 9 (V9) so that the solvent discharged from the feed tank 100, the solvent circulating unit 410 Or may be supplied to the chamber 100 by mixing with the two. In the single supply pipe 150, the flue gas and the carbon dioxide of the gas can be pressurized and dissolved in the solvent.

As an example of the present invention, the carbon dioxide separation device including the single feed pipe 140 in FIG. 11 is merely an example, and the configuration of the device is not limited thereto. For example, the single feed pipe 140 may be coupled to the carbon dioxide separation apparatus of Figs. 5 to 10 and 12.

12, a carbon dioxide separator according to another embodiment of the present invention is illustrated. In FIG. 12, the carbon dioxide separator includes: The liquid supply unit 110, the bypass line 120, the gas supply unit 130, the chamber 200, the gas discharge unit 210, the liquid discharge unit 220, the decompression unit 300 , The deaerating unit 400 and the collecting unit 500 are the same as those shown in FIG. 6 and may further include an infrared lamp 700.

In an example of the present invention, the infrared lamp 700 can increase the solubility of carbon dioxide in the solvent by irradiating infrared rays to the feed tank 100, the chamber 200, or both. For example, the infrared lamp 700 may have a diameter of 3 占 퐉 or more; Or an infrared ray having a wavelength of 4 탆 to 5 탆.

In an example of the present invention, the carbon dioxide separating apparatus including the infrared lamp 700 in FIG. 12 is merely an example, and the constitution of the apparatus is not limited thereto. The infrared lamp 700 may be coupled to the carbon dioxide separation apparatus of Figures 5-11 and may include infrared radiation to at least one of the feed tank 100, the chamber 200, May be configured singularly or plurally.

According to one embodiment of the present invention, a carbon dioxide separation apparatus according to the present invention is a device for separating carbon monoxide (CH ₄ ) and carbon dioxide from a mixed gas containing carbon dioxide, for example, anaerobic digestion tank, , Linz-Donawitz Gas (LDG), and Blast Furnace Gas (BFG).

It will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the following claims And changes may be made without departing from the spirit and scope of the invention.

Example 1

According to the configuration of FIG. 6, the flue gas shown in Table 1 was pressurized and dissolved in a chamber filled with pure water, followed by decompression and degassing to collect carbon dioxide. 4.3 micrometers of infrared radiation was applied to the chamber during pressure melting. The separator was an NF separator (Toray NF90). The solubility, gas concentration, and trap concentration according to each step are shown in Tables 2 to 4.

gas Furtherance Partial pressure N ₂ 70% 0.7 atm O ₂ 10% 0.1 atm CO ₂ 10% 0.1 atm H ₂ O 10% 0.1 atm

(1) the concentration of the gas that can be dissolved in the pressurization step [M]

1 bar flue gas 2 atmospheric pressure flue gas 5 bar flue gas 6 atmospheric pressure flue gas 10 bar flue gas N ₂ 0.000526232 0.001052464 0.00263116 0.003157392 0.00526232 O ₂ 0.00015236 0.00030472 0.0007618 0.00091416 0.0015236 CO ₂ 0.0045463 0.0090926 0.0227315 0.0272778 0.045463

(Henry's constant: N ₂ = 0.00075176M / atm, O ₂ = 0.0015236M / atm, CO ₂ = 0.045463M / atm)

(Concentration of gas dissolved in water = Henry's constant x partial pressure of gas)

(2) Atmospheric pressure  ( 1 atm ) to  After depressurization Degassed  The concentration of gas [M]

1 bar flue gas 2 atmospheric pressure flue gas 5 bar flue gas 6 atmospheric pressure flue gas 10 bar flue gas N2 0.000526232 0.002104928 0.00263116 0.004736088 O2 0.00015236 0.00060944 0.0007618 0.00137124 CO2 0.0045463 0.0181852 0.0227315 0.0409167

(Concentration of gas deaerated by pressure change [M] = concentration of dissolved gas of high-pressure gas [M] - concentration of dissolved gas of low-pressure gas [M]

(3) Atmospheric pressure  ( 1 atm ) to  After depressurization Captured  The composition of gas [ % ]

1 bar flue gas 2 atmospheric pressure flue gas 5 bar flue gas 6 atmospheric pressure flue gas 10 bar flue gas N ₂ 10.07163402 10.07163402 10.07163402 10.07163402 O ₂ 2.916041135 2.916041135 2.916041135 2.916041135 CO ₂ 87.01232485 87.01232485 87.01232485 87.01232485

In Table 2 to 4, 1 g (0.5 liter) of CO ₂ is removed per liter of solution through the process of dissolving flue gas (CO ₂ partial pressure 0.1 atm) at 6 atm in pure water and then reducing pressure to normal pressure (1 atm) And the purity of CO ₂ collected at the end of the process corresponds to 87% (assuming that 1 mole of gas is 22.4 liters at normal temperature / atmospheric pressure). Therefore, through the carbon dioxide separation process according to the present invention, It can be confirmed that the separation and collection performance of carbon dioxide is excellent.

Example 2

According to the configuration of FIG. 6, the flue gas of Table 1 was filled in the chamber again with pure water depleted of carbon dioxide in Example 1, and as shown in Table 5, The discharged gas was injected again into the chamber, and the carbon dioxide separation process was repeated twice. After pressurized dissolution in a chamber filled with pure water, carbon dioxide was collected through decompression and degassing. The solubility, gas concentration and trap concentration according to each step are shown in Tables 5 to 8.

Gas composition Furtherance Partial pressure N ₂ 10.07163402% 0.10071634 atm O ₂ 2.916041135% 0.029160411 atm CO ₂ 87.01232485% 0.870123248 atm

(1) the gas concentration [M] which can be dissolved in water in the pressurization step,

1 bar flue gas 2 atmospheric pressure flue gas 5 bar flue gas 6 atmospheric pressure flue gas 10 bar flue gas N ₂ 7.57145E-05 0.000151429 0.000378573 0.000454287 0.000757145 O ₂ 4.44288E-05 8.88576E-05 0.000222144 0.000266573 0.000444288 CO ₂ 0.039558413 0.079116826 0.197792066 0.237350479 0.395584132

(Henry's constant: N ₂ = 0.00075176M / atm, O ₂ = 0.0015236M / atm, CO ₂ = 0.045463M / atm)

(Concentration of gas dissolved in water = Henry's constant x partial pressure of gas)

(2) Atmospheric pressure  ( 1 atm ) to  After depressurization Degassed  The concentration of gas [M]

1 bar flue gas 2 atmospheric pressure flue gas 5 bar flue gas 6 atmospheric pressure flue gas 10 bar flue gas N ₂ 7.57145E-05 0.000302858 0.000378573 0.000681431 O ₂ 4.44288E-05 0.000177715 0.000222144 0.000399859 CO ₂ 0.039558413 0.158233653 0.197792066 0.356025719

(Concentration of gas deaerated by pressure change [M] = concentration of dissolved gas of high-pressure gas [M] - concentration of dissolved gas of low-pressure gas [M]

(3) Atmospheric pressure  ( 1 atm ) to  After depressurization Captured  The composition of gas [ % ]

1 bar flue gas 2 atmospheric pressure flue gas 5 bar flue gas 6 atmospheric pressure flue gas 10 bar flue gas N ₂ 0.190819733 0.190819733 0.190819733 0.190819733 O ₂ 0.111971822 0.111971822 0.111971822 0.111971822 CO ₂ 99.69720844 99.69720844 99.69720844 99.69720844

Looking at the table 5 to table 8, is dissolved in pure water to the flue gas (CO ₂ partial pressure of 0.1 atm) to atmospheric pressure. 6, when subjected to the step of back pressure to the normal pressure (1 atm) 2 1 CO ₂ 8.7g (4.4 liters per liter ), And the purity of CO ₂ collected at the end of the process is 99.7% (assuming that 1 mole of gas is 22.4 liter volume at normal temperature and normal pressure).

Therefore, it can be confirmed that the carbon dioxide separation efficiency can be improved through repetition of the carbon dioxide separation process.

The present invention can provide a carbon dioxide separation method capable of effectively separating and collecting carbon dioxide in a simple process using the difference in solubility of each component of the flue gas according to the pressure. Further, the present invention can improve the purity of carbon dioxide collected by repeatedly carrying out the carbon dioxide separation process.

Claims (20)

A pressurizing and melting step of pressurizing the flue gas to dissolve carbon dioxide in the pure water;
A separation step of separating the pure water in which the carbon dioxide is dissolved;
A depressurizing step of depressurizing the pure water in which the carbon dioxide is dissolved;
A degassing step of degassing the carbon dioxide from the decompressed pure water; And
A collecting step of collecting the degassed carbon dioxide;
Lt; / RTI >
Wherein the pressure-
Injecting said pure water into a feed tank;
Injecting said pure water into said chamber with a water pressure of at least 3 (bar) and less than 10 (bar); And
Injecting the flue gas into pure water in the chamber at a partial pressure of not less than 3 bar and less than 10 bar to dissolve the carbon dioxide;
Lt; / RTI >
Wherein the pressurization dissolution step is carried out by irradiating infrared rays to promote the pressure dissolution of the carbon dioxide.
delete The method according to claim 1,
Wherein the step of injecting the pure water into the chamber and the step of dissolving the carbon dioxide are carried out sequentially or simultaneously.
The method according to claim 1,
Wherein the pressure-
Injecting said pure water into a feed tank; And
Mixing said flue gas of said pure water with a water pressure of not less than 3 bar and less than 10 bar and said flue gas of not less than 3 bar and less than 10 bar in a single feed pipe and injecting it into the chamber;
Gt; carbon dioxide < / RTI >
The method according to claim 1,
Wherein the pressure-
Injecting said pure water into a feed tank;
Maintaining the water pressure of the pure water above 3 (bar) and below 10 (bar), and bubbling the flue gas into the pure water to dissolve the carbon dioxide; And
Injecting pure water bubbled with said flue gas into said chamber at a water pressure of at least 3 (bar) and less than 10 (bar);
Gt; carbon dioxide < / RTI >
6. The method of claim 5,
Wherein the step of bubbling and dissolving carbon dioxide comprises introducing the flue gas having a partial pressure of 3 bar or more and less than 10 bar into the feed tank and bubbling the carbon dioxide.
The method according to claim 1,
Wherein the separating step separates the pure water in which the gas and the carbon dioxide dissolved in the pure water are dissolved.
The method according to claim 1,
Wherein the pressurized dissolution step uses a flue gas together with a gas that is not dissolved in the pure water separated in the separation step.
The method according to claim 1,
Wherein the decompressing step is performed by reducing the pressure of the pure water in which the carbon dioxide has been dissolved to the atmospheric pressure or regulating the pressure control valve through the separation membrane.
10. The method of claim 9,
The separation membrane is a separation membrane that can operate at a partial pressure of 3 to 20 bar,
Wherein the separation membrane comprises at least one selected from the group consisting of a microfiltration membrane, an ultrafiltration membrane and a nanofiltration membrane.
The method according to claim 1,
The degassing step may include degassing the carbon dioxide in the decompressed pure water,
Wherein after the degassing step, the depressurization step and the degassing step are repeated one or more times by applying pure water in which the carbon dioxide has been degassed.
The method according to claim 1,
Wherein the pure water from which the carbon dioxide has been degassed after the degassing step is injected into the feed tank and applied to the pressure melting step.
The method according to claim 1,
Wherein the step of injecting the flue gas is injected at a partial pressure of at least 3 bar and less than 10 bar.
delete A feed tank filled with pure water;
Liquid supply means for injecting pure water discharged from the feed tank into the chamber at a certain water pressure;
A bypass line for regulating a flow rate of pure water discharged from the feed tank;
Gas supplying means for injecting the flue gas into the chamber at a constant partial pressure;
A chamber in which the carbon dioxide of the flue gas is dissolved in the pure water and the undissolved gas is collected in the upper layer;
Gas discharge means for discharging gas in the upper layer in the chamber;
Liquid discharging means for discharging pure water from the chamber;
A decompression unit for decompressing the discharged pure water;
A deaerator for degassing the carbon dioxide in the decompressed pure water; And
A carbon dioxide collecting unit for collecting the degassed carbon dioxide;
Lt; / RTI >
The pure water is injected into the chamber at a water pressure of 3 bar or more and less than 10 bar,
The flue gas is injected into pure water in the chamber at a partial pressure of at least 3 bar and less than 10 bar,
A single feed pipe for mixing the flue gas of a constant partial pressure and the pure water of constant water pressure discharged from the feed tank into the chamber; Further comprising:
Further comprising an infrared lamp,
Wherein the infrared lamp irradiates infrared rays to at least one of the feed tank, the chamber, and the single supply pipe.
16. The method of claim 15,
Wherein the feed tank comprises: a pressurizing means for pressurizing the pure water at a constant pressure; And a bubbler for injecting flue gas into the pure water; Wherein the carbon dioxide separation device further comprises:
delete delete 16. The method of claim 15,
Wherein the decompression section includes a separation membrane for filtering and discharging the discharged pure water, a pressure control valve, or both.
16. The method of claim 15,
Further comprising a liquid circulating unit for supplying the pure water deaerated in the degassing unit to at least one of the feed tank, the chamber, the single feed pipe, and the pressure reducing unit.

Images