Carbon dioxide absorption system

Abstract

The present invention relates to a carbon dioxide absorption device comprising: a first housing; a first storage tank configured inside the first housing and storing a carbon dioxide absorbent therein; and a membrane contactor configured inside the first housing, into which the carbon dioxide absorbent is introduced from the first storage tank and air is introduced from outside the first housing so that the carbon dioxide absorbent absorbs carbon dioxide from the air by membrane contact; and a carbon dioxide regeneration device comprising: a second housing; a third storage tank configured inside the second housing and storing a saturated carbon dioxide absorbent therein; a degassing reactor configured inside the second housing into which the saturated carbon dioxide absorbent is introduced from the third storage tank and separates carbon dioxide from the saturated carbon dioxide absorbent by degassing; a third storage tank receiving and storing the regenerated carbon dioxide absorbent from the degassing reactor; and a carbon dioxide storage tank receiving and storing the carbon dioxide separated from the degassing reactor.

Description

Technology Field

[0001] The present invention relates to a system comprising a device capable of controlling the concentration of carbon dioxide in indoor air, etc., and a device for regenerating a carbon dioxide absorbent used in such a device. Background Technology

[0003] Carbon dioxide is generally present in the atmosphere at a concentration of 0.03 to 0.04%, and carbon dioxide itself does not typically have a significant impact on human health. However, when carbon dioxide levels increase in indoor spaces, the amount of oxygen required for breathing becomes insufficient, leading to symptoms such as headaches, lethargy, dizziness, vomiting, and discomfort; therefore, it is considered a significant indoor air pollutant.

[0004] Previously, fine dust and airborne microorganisms were classified as the most important air pollutants in indoor spaces, but recently, interest in carbon dioxide has been rapidly increasing.

[0005] Carbon capture and storage (CCS) technology is being actively researched as a method to selectively separate and isolate such carbon dioxide. In particular, methods for selectively separating only carbon dioxide from exhaust gases include cryogenics, membrane separation, absorption, and adsorption.

[0006] However, research on technologies that enable the miniaturization of these carbon dioxide absorption methods to control carbon dioxide concentration indoors is relatively limited. Prior art literature

[0008] Republic of Korea Patent Registration No. 943537 The problem to be solved

[0009] The present invention has been devised to solve the above-mentioned problems and aims to provide a system comprising a device installed indoors to control indoor carbon dioxide concentration and a device for regenerating a carbon dioxide absorbent used in such a device. means of solving the problem

[0011] A carbon dioxide absorption system according to the present invention for achieving the above-mentioned purpose (hereinafter referred to as the "system of the present invention") comprises: a first housing; a first storage tank configured inside the first housing and storing a carbon dioxide absorbent therein; and a membrane contactor configured inside the first housing, wherein the carbon dioxide absorbent is introduced from the first storage tank and air is introduced from outside the first housing, thereby allowing the carbon dioxide absorbent to absorb carbon dioxide from the air through membrane contact; A carbon dioxide regeneration device comprising: a second housing; a second storage tank configured inside the second housing and storing a carbon dioxide absorbent saturated therein; a degassing reactor configured inside the second housing, into which the carbon dioxide absorbent saturated from the second storage tank is introduced to separate carbon dioxide from the saturated carbon dioxide absorbent by degassing; a third storage tank receiving and storing the carbon dioxide absorbent regenerated from the degassing reactor; and a carbon dioxide storage tank receiving and storing the carbon dioxide separated from the degassing reactor; wherein the carbon dioxide absorbent comprises, for every 100 parts by weight of one polyamine selected from ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetraamine (TETA), 50 to 200 parts by weight of one or more amino acids selected from glycine, alanine, and gamma-aminobutyric acid (GABA), 1 to 5 parts by weight of piperazine, and 1 to It is characterized by comprising 5 parts by weight, 0.5 to 3 parts by weight of fulvic acid, and 0.5 to 3 parts by weight of magnesium aluminum silicate.

[0012] As one example, the membrane contactor comprises: an air inlet line that allows air to flow in from outside the first housing to the bottom; a membrane contact section that allows the inlet air and the carbon dioxide absorbent to react so that the carbon dioxide absorbent absorbs carbon dioxide from the air; an air discharge line that discharges air from which carbon dioxide has been removed at the top of the membrane contact section to the outside of the first housing; an absorbent inlet line that allows the carbon dioxide absorbent from the first storage tank to flow into the top of the membrane contact section; and an absorbent discharge line that discharges the carbon dioxide absorbent, from which carbon dioxide has been absorbed at the bottom of the membrane contact section, to the first storage tank.

[0013] As an example, the first housing is configured with a sensor capable of measuring carbon dioxide concentration, the air inlet line is configured with a blower, the absorbent inlet line is configured with a pump, and a first control unit is configured to control the blower or the pump in conjunction with the sensor.

[0014] As an example, the second housing is further configured with a pressure reducing pump, and is characterized by further configured with a second control unit that controls the pressure reducing pump.

[0015] As an example, the saturated carbon dioxide absorbent of the second storage tank is introduced into the cyclone separator at the downstream end to filter out foreign substances from the saturated carbon dioxide absorbent, and the saturated carbon dioxide absorbent from which foreign substances have been filtered is introduced into the degassing reactor.

[0016] As one example, the above-described cyclone separator is characterized by comprising: an inverted cone-shaped body portion that induces a vortex, with an inflow line formed at the top and a foreign substance discharge line formed at the bottom for discharging foreign substances; a heating means formed on the outer periphery of the body portion; a guide tube with a lower portion exposed to the inside of the body portion and an upper portion exposed to the outside of the body portion; an absorbent collection portion formed in a shape that surrounds the guide tube, with an absorbent discharge line formed to collect a carbon dioxide absorbent overflowing the top of the guide tube and discharge the carbon dioxide absorbent to a degassing reactor at the rear end, and having an open upper surface; a gas-liquid separation membrane formed at the opening; and a carbon dioxide collection portion that collects the separated carbon dioxide on the upper part of the gas-liquid separation membrane and discharges the collected carbon dioxide to the carbon dioxide storage tank.

[0017] As one example, the carbon dioxide absorbent is characterized by further including 0.1 to 1 weight part of ammonium thiocyanate.

[0018] delete

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[0021] delete Effects of the invention

[0023] As explained above, the system of the present invention has the advantage of not only being able to control the amount of carbon dioxide indoors, such as in school classrooms, but also being able to easily regenerate the saturated carbon dioxide absorbent.

[0024] In addition, the system of the present invention has the advantage of being able to improve durability as well as have excellent carbon dioxide removal efficiency by applying an appropriate carbon dioxide absorbent.

[0025] In addition, the system of the present invention has the advantage of being able to reduce the load and improve durability. Brief explanation of the drawing

[0027] FIG. 1 is a schematic diagram showing a basic example of the present invention. FIGS. 2 and FIGS. 3 are operating state diagrams of partial components of the present invention. FIG. 4 is a side cross-sectional view showing one embodiment of the present invention. Specific details for implementing the invention

[0028] A preferred embodiment according to the present invention will be described in detail below.

[0030] As shown in FIG. 1, the system (1) of the present invention comprises a carbon dioxide absorption device (2) including a first housing (21), a first storage tank (23) configured inside the first housing (21) and storing a carbon dioxide absorbent therein, and a membrane contactor (22) configured inside the first housing (21) to allow the carbon dioxide absorbent to flow in from the first storage tank (23) and air to flow in from outside the first housing (21) so that the carbon dioxide absorbent absorbs carbon dioxide from the air through membrane contact; The carbon dioxide regeneration device (3) is characterized by including: a second housing (31); a second storage tank (32) configured inside the second housing (31) and storing a carbon dioxide absorbent saturated therein; a degassing reactor (33) configured inside the second housing (31) into which the carbon dioxide absorbent saturated from the second storage tank (32) is introduced and which separates carbon dioxide from the carbon dioxide absorbent saturated by degassing; a third storage tank (34) that receives and stores the carbon dioxide absorbent regenerated from the degassing reactor (33); and a carbon dioxide storage tank (35) that receives and stores the carbon dioxide separated from the degassing reactor (33).

[0031] First, the carbon dioxide absorption device (2) will be explained.

[0032] The first housing (21) above has a space formed inside so that a membrane contactor (22), a first storage tank (23), etc. are housed in the space, and although not shown in the drawing, a structure that can be opened and closed must be applied.

[0033] The first storage tank (23) is configured to store a carbon dioxide absorbent, and the carbon dioxide absorbent stored in the first storage tank (23) is supplied to the membrane contactor (22), and the carbon dioxide absorbent that has absorbed carbon dioxide in the membrane contactor (22) is then fed back into the first storage tank (23).

[0034] The above membrane contactor (22) is configured such that the carbon dioxide absorbent absorbs carbon dioxide from the air through a reaction caused by membrane contact between the air and the carbon dioxide absorbent, and the air from which the carbon dioxide has been removed is discharged to the outside.

[0035] To this end, the membrane contactor (22) is characterized by including an air inlet line that allows air to flow in from outside the first housing (21) to the bottom, although no drawing number is shown; a membrane contact part that allows the inlet air and the carbon dioxide absorbent to react so that the carbon dioxide absorbent absorbs carbon dioxide from the air; an air discharge line that allows the air from which carbon dioxide has been removed at the top of the membrane contact part to be discharged to the outside of the first housing (21); an absorbent inlet line that allows the carbon dioxide absorbent from the first storage tank (23) to flow into the top of the membrane contact part; and an absorbent discharge line that allows the carbon dioxide absorbent from which carbon dioxide has been absorbed at the bottom of the membrane contact part to be discharged to the first storage tank (23).

[0036] Air from outside the first housing (21) is introduced to the bottom of the membrane contactor (22) through the air inlet line, and the air introduced in this way rises and passes through the membrane contact part. During this process, the carbon dioxide absorbent introduced to the membrane contact part through the absorbent inlet line descends, and the reaction mentioned above occurs through membrane contact between the rising air and the descending carbon dioxide absorbent.

[0037] Since the reaction of these membrane contact parts corresponds to a known mechanism of operation, a detailed description thereof is omitted.

[0038] The air from which carbon dioxide has been removed at the above membrane contact section is discharged to the outside of the first housing (21) through the air discharge line, and the carbon dioxide absorbent from which carbon dioxide has been absorbed is discharged to the first storage tank (23) through the absorbent discharge line.

[0039] In addition, the first housing (21) is configured with a sensor (26) capable of measuring carbon dioxide concentration, the air inlet line is configured with a blower (24), the absorbent inlet line is configured with a pump (231), and the first control unit (27) is configured to control the blower (24) or the pump (231) in conjunction with the sensor (26).

[0040] The carbon dioxide concentration in the room is measured by the sensor (26), and in order to meet the carbon dioxide standard of the indoor air, the first control unit (27) controls the blower (24) to control the amount of air flowing into the membrane contactor (22) or controls the pump (231) to control the amount of carbon dioxide absorbent flowing into the membrane contactor (22).

[0041] To this end, the first control unit (27) is configured with an analysis unit, although not shown in the drawing, to compare the carbon dioxide concentration of indoor air measured by the sensor (26) with a preset carbon dioxide standard value to derive the amount of incoming air and the amount of incoming carbon dioxide absorbent, and to control the operation of the blower (24) or the pump (231) based on the derived data.

[0042] In addition, although not shown in the drawing, an example is presented in which a filter unit is further configured in the air discharge line to remove foreign substances from the air from which carbon dioxide has been removed and discharge it.

[0043] The air from which carbon dioxide has been removed while passing through the membrane contactor (22) may contain fine particles that may be generated during the reaction process with the carbon dioxide absorbent, and such foreign substances are removed in the filter section and discharged outside the first housing (21).

[0044] In addition, foreign substances that can be removed by the filter unit may include moisture, bacteria, etc., in addition to the fine particles; therefore, the filter unit may be configured in combination with components capable of removing moisture, antibacterial action, and filtration of fine particles.

[0045] Next, the carbon dioxide regeneration device (3) is described.

[0046] The second housing (31) has a space formed inside so that a degassing reactor (33), second and third storage tanks (32, 34), etc. are housed in the space, and although not shown in the drawing, a structure that can be opened and closed must be applied.

[0047] The above second storage tank (32) is configured to store a saturated carbon dioxide absorbent, and the saturated carbon dioxide absorbent is introduced from the first storage tank (23) of the carbon dioxide absorption device (2), and is defined as a carbon dioxide absorbent that has been used and requires regeneration.

[0048] The above degassing reactor (33) corresponds to a configuration in which a saturated carbon dioxide absorbent is introduced from the above second storage tank (32) and a degassing reaction is performed to separate carbon dioxide from the saturated carbon dioxide absorbent by degassing.

[0049] The above degassing reactor (33) may be equipped with various known technologies, for example, a membrane contact method. The membrane contact method is intended to regenerate the absorbent in which carbon dioxide has been absorbed, and to maximize the contact area between the absorbent and the atmosphere.

[0050] The carbon dioxide saturated into the lumen side (inside of the tube) is allowed to flow through the absorbent, and although not shown in the drawing, air is allowed to flow through the shell side (outer part), thereby separating the carbon dioxide from the saturated carbon dioxide absorbent in the membrane forming the tube by a known operating mechanism.

[0051] The third storage tank (34) is configured to receive and store the regenerated carbon dioxide absorbent from the degassing reactor (33), and the regenerated carbon dioxide absorbent stored in the third storage tank (34) is supplied back to the first storage tank (23) of the carbon dioxide absorption device (2).

[0052] The carbon dioxide storage tank (35) above is configured to receive and store carbon dioxide separated from the degass reactor (33). The carbon dioxide stored in this way can be introduced into a known device, which is not shown in the drawing, and converted into calcium carbonate, etc., to be recycled in civil engineering, construction, etc.

[0053] In addition, in the present invention, as shown in FIG. 1, a pressure reducing pump (38) may be further configured in the second housing (31), and as shown in FIG. 3, the pressure reducing pump (38) may be controlled by the second control unit (37).

[0054] The operating mechanism of the pressure pump (38) in the degassing reaction is a known operating mechanism, so a detailed description thereof is omitted.

[0055] In addition, the second control unit (37) is capable of controlling the heating means (392) described below.

[0056] To this end, although not shown in the drawing, it is reasonable to configure a pressure sensor and a temperature sensor in the second housing (31) so that the pressure reducing pump (38) and the heating means (392) are automatically controlled in conjunction with these sensors.

[0057] That is, although not shown in the drawing, the second control unit (37) is configured with an analysis unit to compare the pressure and temperature values ​​measured by the sensor with preset reference values ​​so that the pressure reduction pump (38) and the heating means (392) are controlled.

[0058] Meanwhile, the saturated carbon dioxide absorbent contains foreign substances such as reaction products, and the present invention provides an example in which a cyclone separator (39) is further configured to remove such foreign substances and simultaneously reduce the load on the subsequent degassing reactor (33).

[0059] The above cyclone separator (39) is characterized by allowing the saturated carbon dioxide absorbent of the second storage tank (32) to be introduced so that foreign substances are filtered from the saturated carbon dioxide absorbent, and allowing the saturated carbon dioxide absorbent from which foreign substances have been filtered to be introduced into the degassing reactor (33), while simultaneously separating carbon dioxide from the saturated carbon dioxide absorbent and supplying the separated carbon dioxide to the carbon dioxide storage tank (35).

[0060] To explain the above cyclone separator (39) in more detail, it comprises an inverted cone-shaped body part (391) that induces a vortex, having an inflow line (391-1) formed at the top and a foreign matter discharge line (391-2) formed at the bottom for discharging foreign matter; a heating means (392) formed on the outer periphery of the body part (391); a guide tube (393) whose lower end is exposed to the inside of the body part (391) and whose upper end is exposed to the outside of the body part (391); an absorbent collection part (394) which is configured in a shape that surrounds the guide tube (393), has an absorbent discharge line (394-1) that collects carbon dioxide absorbent overflowing from the top of the guide tube (393) and discharges the carbon dioxide absorbent to a degassing reactor (33) at the rear end, and has an open upper surface; a gas-liquid separation membrane (395) formed at the opening; and the It is characterized by including a carbon dioxide capture unit (396) that captures separated carbon dioxide on the upper part of the gas-liquid separation membrane (395) and discharges the captured carbon dioxide to the carbon dioxide storage tank (35).

[0061] The above body part (391) is configured in an inverted cone shape and is configured to form a vortex through a known operating mechanism. An inlet line (391-1) is formed at the top through which a saturated carbon dioxide absorbent is introduced from the second storage tank (32). As the introduced saturated carbon dioxide absorbent forms a vortex, foreign substances with a relatively high specific gravity descend along the wall of the above body part (391) by centrifugal force and are discharged through the foreign substance discharge line (391-2), and the saturated carbon dioxide absorbent from which foreign substances have been removed rises along the guide pipe (393).

[0062] However, the saturated carbon dioxide absorbent rising along the guide tube (393) may also contain foreign substances with a specific gravity similar to that of the saturated carbon dioxide absorbent. As shown in the drawing, the guide tube (393) is further configured with a filter (393-1) to remove foreign substances with a specific gravity similar to that of the saturated carbon dioxide absorbent.

[0063] The saturated carbon dioxide absorbent from which foreign substances have been removed in this way overflows the top of the guide tube (393) and is collected in the absorbent collection unit (394), and the collected carbon dioxide absorbent is discharged to the degassing reactor (33) through the absorbent discharge line (394-1).

[0064] In this way, heating is performed by the heating means (392) during the flow process by vortex in the body (391) and guide tube (393) of the saturated carbon dioxide absorbent, and degassing of carbon dioxide is performed from the saturated carbon dioxide absorbent by heating.

[0065] Since various known technologies can be applied to this heating means (392), a detailed description thereof is omitted.

[0066] In this way, the degassing of carbon dioxide is partially carried out before the degassing reactor (33), thereby reducing the load of the degassing reactor (33). For example, in the case of membrane contact, the load of the degassing reactor (33) may be reduced due to membrane clogging caused by an increase in the amount of carbon dioxide degassing.

[0067] The carbon dioxide thus degassed rises in the induction tube (393), passes through the gas-liquid separation membrane (395), and is collected in the carbon dioxide collection unit (396). The carbon dioxide collected in the carbon dioxide collection unit (396) is discharged to the carbon dioxide storage tank (35) through the carbon dioxide discharge line (396-1).

[0068] The above gas-liquid separation membrane (395) is configured to selectively allow only carbon dioxide mixed into a saturated carbon dioxide absorbent to pass through, and it is obvious that various known materials can be applied.

[0069] In addition, the present invention provides an embodiment of a carbon dioxide absorbent, wherein the carbon dioxide absorbent of this embodiment is characterized by comprising polyamine, amino acid, and piperazine.

[0070] The above polyamine is characterized by being a linear polyamine as shown in the following chemical formula.

[0071]

[0072]

[0073]

[0074] High viscosity and high surface tension are required as characteristics of an absorbent capable of controlling the membrane wetting of a membrane contactor. To this end, the present invention 1) uses a linear polyamine having two or more amino groups as a backbone to increase the viscosity of the absorbent solution while allowing multiple amino groups to absorb CO2, and 2) attaches an amino acid to the amino group at the end of the polyamine to increase the surface tension of the solution, thereby resulting in high CO2 absorption capacity and low membrane pore wetting characteristics (synergistic effect of viscosity and surface tension).

[0075] As explained above, in order to increase CO2 absorption capacity and viscosity, it is preferable that the linear polyamine be one or more selected from ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetraamine (TETA), and to increase surface tension, an equimolar or greater number of amino acids per mole of polyamine are mixed to form a macromolecule, and it is appropriate to use one or more selected from amino acids whose surface tension increases as their concentration increases, such as glycine, alanine, and gamma-aminobutyric acid (GABA).

[0076] The above piperazine is intended to enable the function of a reaction accelerator.

[0077] Preferably, it is appropriate to formulate the mixture to include 50 to 200 parts by weight of amino acid and 1 to 5 parts by weight of piperazine per 100 parts by weight of polyamine.

[0078] Meanwhile, it has been confirmed that amine-based absorbents used for a long period of time have reduced carbon dioxide absorption capacity or converted into other components that are not easily regenerated. This amine degradation not only essentially lowers the carbon dioxide absorption rate but also acts as a factor that reduces the durability of the capture equipment, such as foaming, corrosion, and fouling.

[0079] Amine degradation occurs due to various causes, among which side reactions caused by oxygen contained in flue gas are a cause. Flue gas from coal-fired power plants contains about 4 to 8% oxygen, and when carbon dioxide is captured from such flue gas, amine absorbents generate various modified products such as ammonia, aldehyde, ketone, amide, and carboxylic acid due to side reactions with oxygen.

[0080] Accordingly, the present invention provides an example in which diosmetine is further included in addition to the above compositions to control the side reaction with oxygen of the amine series.

[0081] In other words, the addition of diosmetine controls side reactions of polyamines and the like with oxygen contained in the flue gas.

[0082] Preferably, it is reasonable to incorporate 1 to 5 parts by weight of diosmetine per 100 parts by weight of the polyamine.

[0083] Furthermore, as mentioned above, the aforementioned amine modification is induced by an oxidation reaction with oxygen contained in the flue gas, and Fe as an impurity in the flue gas 3 + , Fe 2 + , Cu + In the presence of metal ions, there is a problem in that oxidative degradation is accelerated due to the catalytic action of the metal ions.

[0084] Accordingly, in the present invention, in addition to controlling the oxidation of amine systems by adding the above-mentioned diosmetine, fulvic acid is further added to Fe 3 + , Fe 2 + , Cu + By removing metal ions such as the metal ions, the oxidative degradation promoted by the catalytic action of metal ions is controlled, thereby further increasing the control efficiency of amine degradation.

[0085] The above fulvic acid is a chelate compound that combines with metal ions in an aqueous solution to form a complex, thereby controlling the catalytic action of the metal ions.

[0086] Preferably, it is reasonable to mix 0.5 to 3 parts by weight of fulvic acid with respect to 100 parts by weight of the polyamine.

[0087] However, metal ions mixed in flue gas can be classified into monovalent cations, divalent cations, and trivalent cations. Among these, monovalent cations generally dissolve well in water, and even when precipitated in the form of salts, they tend to be highly soluble in water.

[0088] On the other hand, divalent and trivalent cations do not dissolve well in water, which can cause scale to form on the membrane, ultimately lowering the carbon dioxide removal rate of the absorbent and acting as a factor that reduces the durability of the membrane.

[0089] That is, the complex compound formed by combining fulvic acid and metal ions is deposited on the membrane to form scale, and the present invention provides an example in which magnesium aluminum silicate is further included to remove such complex compounds.

[0090] The magnesium aluminum silicate is formed into a three-dimensional crystal structure and possesses the property of adsorbing other components. As a result, the magnesium aluminum silicate mixes well with other water-soluble compositions, and in particular, adsorbs the complex compounds, thereby controlling scale formation on the aforementioned film through the precipitation of the complex compounds.

[0091] In addition, the inclusion of magnesium aluminum silicate further increases viscosity, thereby further increasing the control efficiency of membrane wetting.

[0092] Preferably, it is appropriate to mix 0.5 to 3 parts by weight of magnesium aluminum silicate with respect to 100 parts by weight of the polyamine.

[0093] Meanwhile, the carbon dioxide absorption reaction by the carbon dioxide absorbent is an exothermic reaction, and additionally, piperazine is added to the absorbent of the present invention as a reaction promoter. As the reaction is promoted by the addition of piperazine, the amount of heat increases, and due to this heat, the surface tension decreases, which may lead to a problem where the effect of controlling membrane wetting by the addition of amino acids, as mentioned above, is reduced.

[0094] Accordingly, the present invention presents an example in which ammonium thiocyanate (NH4SCN) is further added in addition to the above compositions. By lowering the heat of thiocyanate through the addition of ammonium thiocyanate, the reduction of surface tension is controlled.

[0095] Preferably, it is appropriate to mix 0.1 to 1 part by weight of ammonium thiocyanate with 100 parts by weight of polyamine.

[0097] A preferred embodiment of the absorbent in the present invention is described below based on experimental examples.

[0099] <Example 1>

[0100] A sample was prepared by including 10 parts by weight of glycine and 0.2 parts by weight of piperazine with 10 parts by weight of triethylenetetraamine with 10 parts by weight of water, and during the preparation of the sample, synthesis was achieved by the interaction of the deprotonated carboxyl group of the amino acid and the amino group at the end of the linear polyamine in an aqueous solution.

[0102] <Example 2>

[0103] A sample was prepared in the same manner as in Example 1, but with an additional 0.1 weight part of diosmetine added.

[0105] <Example 3>

[0106] A sample was prepared in the same manner as in Example 2, but with an additional 0.05 parts by weight of fulvic acid added.

[0108] <Example 4>

[0109] A sample was prepared in the same manner as in Example 3, but with an additional 0.05 parts by weight of magnesium aluminum silicate added.

[0111] <Example 5>

[0112] A sample was prepared in the same manner as in Example 1, but with an additional 0.01 parts by weight of ammonium thiocyanate added.

[0114] As shown below, the carbon dioxide absorption performance was measured by using a gas composition of CO2 50%, CH4 40%, and O2 10% to simulate a mixed gas composition, performing absorption at 40°C and desorption at 80°C to measure the cyclic CO2 capacity, and the membrane pore wetting characteristics were confirmed by measuring the critical entry pressure (CEP), which is the pressure at which the absorbent solution penetrates the pores and flows out to the opposite side, using a flat membrane with a pore size of 45 μm.

[0116] The carbon dioxide absorption capacity of each sample was tested. Table 1 below shows the operating conditions, and the experiment was performed according to the following experimental flow.

[0118] Absorption temperature (°C) 40 CO2 flow rate (ml / min) 600 Detachment temperature (°C) 80 CO2 concentration (v / v%) 50 Absorbent volume (ml) 200 CH4balance

[0120] Experiment Flow

[0121] ① This experiment is CO 2, Using CH4 gas, set the volume of CO2 gas to be flowed first to 50 v / v%.

[0122] ② Place the reactor in a water bath set to 40℃ and flow the gas set in ① into the reactor to start CO2 absorption.

[0123] ③ When the CO2 concentration of the absorbent reaches 49%, stop CO2 injection to terminate absorption, and remove the CO2 remaining in the reactor and tubes (prevention of physical absorption).

[0124] ④ Transfer the reactor to a water bath set to 80℃, start stripping with only methane injected into the reactor, and terminate all experiments when the CO2 concentration reaches 5%.

[0126] Cyclic capacity (mol / L) BAR Example 1 1.00133 3.05 Example 2 1.610221 3.01 Example 3 1.788221 3.11 Example 4 1.801121 4.01 Example 5 1.1189011 3.98

[0128] As shown in Table 2 above, the cyclic capacity is the amount of CO2 that can be removed per cycle, and it can be seen that the case of Example 2 is higher than that of Example 1. This is attributed to the fact that in the case of Example 2, more diosmetine was added to control the side reactions of polyamines, etc. with oxygen.

[0129] In addition, it can be seen that the cases of Examples 3 and 4 are higher than that of Example 2, which is attributed to the fact that in the case of Examples 3 and 4, additional fulvic acid is added to remove metal ions, thereby controlling the catalytic action in the oxidation of metal ions.

[0130] In addition, experiments on membrane pore wetting were conducted using a critical permeation pressure measuring device, and it was determined that the higher the measured CEP, the more the wetting is controlled. The experimental results are shown in Table 2 above.

[0131] It can be seen that the measured CEP in Example 4 is higher than in Example 3, which is attributed to the fact that Example 4 contains more magnesium aluminum silicate, which adsorbs the complex compound formed by the addition of fulvic acid in Example 3 to control scale formation on the membrane, and also increases viscosity to further improve the control efficiency of membrane wetting.

[0132] In addition, it can be seen that the membrane wetting control efficiency is high in the case of Example 5, which is attributed to the addition of ammonium thiocyanate to Example 5, which lowers the surface tension.

[0134] As described above, although the present invention has been explained by limited embodiments and drawings, the present invention is not limited to the above embodiments, and it is obvious that various modifications and variations from the description above may be possible by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0136] 1: System of the present invention 2: Carbon dioxide absorption device 3 : Carbon dioxide regeneration device

Claims

Claim 1 A carbon dioxide absorption device comprising: a first housing; a first storage tank configured inside the first housing and storing a carbon dioxide absorbent therein; and a membrane contactor configured inside the first housing, wherein the carbon dioxide absorbent is introduced from the first storage tank and air is introduced from outside the first housing to allow the carbon dioxide absorbent to absorb carbon dioxide from the air through membrane contact. A carbon dioxide regeneration device comprising: a second housing; a second storage tank configured inside the second housing and storing a carbon dioxide absorbent saturated therein; a degassing reactor configured inside the second housing, into which the carbon dioxide absorbent saturated from the second storage tank is introduced to separate carbon dioxide from the saturated carbon dioxide absorbent by degassing; a third storage tank receiving and storing the carbon dioxide absorbent regenerated from the degassing reactor; and a carbon dioxide storage tank receiving and storing the carbon dioxide separated from the degassing reactor; wherein the carbon dioxide absorbent comprises, for every 100 parts by weight of one polyamine selected from ethylenediamine (EDA), diethylenetriamine (DETA), and triethylenetetraamine (TETA), 50 to 200 parts by weight of one or more amino acids selected from glycine, alanine, and gamma-aminobutyric acid (GABA), 1 to 5 parts by weight of piperazine, and 1 to 5 parts by weight of diosmetine. A carbon dioxide absorption system characterized by comprising 0.5 to 3 parts by weight of fulvic acid and 0.5 to 3 parts by weight of magnesium aluminum silicate. Claim 2 A carbon dioxide absorption system according to claim 1, wherein the membrane contactor comprises: an air inlet line for allowing air to flow in from outside the first housing to the bottom; a membrane contact section for allowing the carbon dioxide absorbent to react with the inlet air to absorb carbon dioxide from the air; an air discharge line for discharging air from which carbon dioxide has been removed at the top of the membrane contact section to the outside of the first housing; an absorbent inlet line for allowing the carbon dioxide absorbent from the first storage tank to flow into the top of the membrane contact section; and an absorbent discharge line for discharging the carbon dioxide absorbent from which carbon dioxide has been absorbed at the bottom of the membrane contact section to the first storage tank. Claim 3 A carbon dioxide absorption system according to claim 2, characterized in that a sensor capable of measuring carbon dioxide concentration is configured in the first housing, a blower is configured in the air inlet line, a pump is configured in the absorbent inlet line, and a first control unit is configured to control the blower or the pump in conjunction with the sensor. Claim 4 A carbon dioxide absorption system according to claim 1, characterized in that a pressure reducing pump is further configured in the second housing, and a second control unit for controlling the pressure reducing pump is further configured. Claim 5 A carbon dioxide absorption system according to claim 4, characterized in that the saturated carbon dioxide absorbent of the second storage tank is introduced into a cyclone separator at the rear end to filter out foreign substances from the saturated carbon dioxide absorbent, and the saturated carbon dioxide absorbent from which foreign substances have been filtered is introduced into the degassing reactor. Claim 6 In claim 5, the cyclone separator comprises: an inverted cone-shaped body portion that induces a vortex, having an inflow line formed at the top and a foreign matter discharge line formed at the bottom for discharging foreign matter; a heating means formed on the outer periphery of the body portion; a guide tube with a lower portion exposed to the inside of the body portion and an upper portion exposed to the outside of the body portion; an absorbent collection portion formed in a shape that surrounds the guide tube, having an absorbent discharge line formed to collect a carbon dioxide absorbent overflowing the top of the guide tube and discharge the carbon dioxide absorbent to a degassing reactor at the rear end, and having an open upper surface; a gas-liquid separation membrane formed at the opening; and a carbon dioxide collection portion that collects carbon dioxide separated on the upper part of the gas-liquid separation membrane and discharges the collected carbon dioxide to the carbon dioxide storage tank. Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 delete Claim 11 A carbon dioxide absorption system according to claim 1, characterized in that the carbon dioxide absorbent further comprises 0.1 to 1 weight part of ammonium thiocyanate.

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