A method and system for absorbing carbon dioxide

Abstract

The present invention discloses a carbon dioxide absorption method and absorption system. The device comprises an absorption box; a liquid recovery tank and a liquid outlet pipe are provided at the bottom of the absorption box, and a first valve is provided on the liquid outlet pipe; a "T"-shaped first liquid spray pipe is provided at the top of the absorption box, and a first rotating motor is provided above the absorption box; the top of the first liquid spray pipe extends into the first sleeve, and the other end of the first sleeve is fixedly connected to the first liquid inlet pipe; a "T"-shaped second liquid spray pipe is provided above the liquid recovery tank; the lower part of the second liquid spray pipe is fixedly connected to the second rotating motor; the end of the second liquid spray pipe extends into the second sleeve, and the other end of the second sleeve is fixedly connected to the second liquid inlet pipe; a plurality of air inlet pipes are provided on the side wall of the absorption box; and a plurality of air outlets are provided at the top of the absorption box. The system of the present invention absorbs carbon dioxide with a hyperbranched polyamine carbon dioxide absorbent, and can also obtain a carbon-rich fluid, which can be used to increase oil recovery, improve the absorption rate of carbon dioxide reduction, and reduce the absorption cost after recovery.

Description

Technical Field

[0001] The invention relates to the technical field of CCUS, and in particular to a method and system for absorbing carbon dioxide using a hyperbranched polyamine carbon dioxide absorbent. Background Art

[0002] By capturing, storing and actively utilizing the emitted carbon elements, we develop the capture, utilization and storage technology (CCUS) of CO2 with the fundamental feature of reducing the carbon content in the atmosphere. The ideal situation is to achieve zero carbon emissions. At present, the main methods for capturing CO2 from various mixed gases are chemical absorption, pressure swing adsorption, membrane treatment and low-temperature fractionation. Chemical absorption is the most mature, and the others are mainly in the practical / experimental stage. Due to the large consumption of regeneration steam, high regeneration energy consumption, strong corrosiveness of high-temperature solution, easy degradation of solution, large solvent loss, high equipment investment cost, huge capture equipment, low cycle efficiency, and reduced power generation efficiency of power plants, etc. The traditional CO2 capture process is to convert gaseous CO2 into a solution state through the reaction of absorbent and CO2, and then decompose and analyze it at high temperature (>120℃), purify and compress it, and then store it for external transportation for storage. This carbon dioxide capture and storage technology (CCS) is relatively expensive. A hyperbranched polyamine carbon dioxide absorbent is a new type of carbon dioxide absorbent. After absorbing carbon dioxide, it reacts to generate a carbon-rich fluid, which can be used as an oil displacement agent to increase the recovery rate of oil. In this way, carbon dioxide can be stored in oil and gas fields, and the recovery rate of oil can be increased, and the cost of carbon dioxide capture and storage technology (CCS) can be reduced, achieving multiple goals at one stroke. Therefore, a method and a system for absorbing carbon dioxide with a hyperbranched polyamine carbon dioxide absorbent are needed to increase the absorption rate of carbon dioxide and recover the carbon-rich fluid for oil production. Summary of the invention

[0003] In view of the above prior art, the purpose of the present invention is to provide a method and system for absorbing carbon dioxide using a hyperbranched polyamine carbon dioxide absorbent. The system of the present invention can improve the absorption rate of carbon dioxide, and the absorbent can also obtain carbon-rich fluid after absorbing carbon dioxide, which can be used to improve oil recovery after recovery.

[0004] To achieve the above object, the present invention adopts the following technical solution:

[0005] According to a first aspect of the present invention, there is provided a carbon dioxide absorption system, comprising an absorption box; a liquid recovery pool is provided at the bottom of the absorption box, a liquid outlet pipe is provided at the bottom of the liquid recovery pool, and a first valve is provided on the liquid outlet pipe; a "T"-shaped first liquid spray pipe is provided at the top of the absorption box, and a plurality of first nozzles with openings facing downward are provided on the first liquid spray pipe; a first rotating motor is provided above the absorption box, and the first rotating motor is fixedly connected to the first liquid spray pipe; the top end of the first liquid spray pipe extends into a first sleeve, and the other end of the first sleeve is fixedly connected to a first liquid inlet pipe; a "T"-shaped second liquid spray pipe is provided above the liquid recovery pool, and a plurality of first nozzles with openings facing downward are provided on the second liquid spray pipe. a second nozzle with an upward opening; the lower part of the second liquid spray pipe is fixedly connected to the second rotating motor; the end of the second liquid spray pipe extends into the second sleeve, and the other end of the second sleeve is fixedly connected to the second liquid inlet pipe; the second liquid inlet pipe passes through the side wall of the absorption box and is connected to the outer wall; a plurality of air inlet pipes are arranged on the side wall of the absorption box, and the air inlet pipes are located between the first liquid spray pipe and the second liquid spray pipe; a plurality of air outlets are arranged on the top of the absorption box; the air inlet pipe is connected to the gas cooler through a pipeline; the first liquid inlet pipe and the second liquid inlet pipe are respectively connected to the absorbent configuration box through pipelines, and the absorbent configuration box is respectively provided with a water pipe and an absorbent pipe; the liquid outlet pipe is connected to the liquid storage tank through a pipeline.

[0006] Preferably, a plurality of stirrers are provided on the bottom and top side walls of the liquid recovery tank. The stirrer is provided on the top side wall to mix gas and liquid, further mix the unabsorbed carbon dioxide with the absorption liquid, and improve the absorption efficiency.

[0007] Preferably, the spraying ranges of adjacent first nozzles are connected or partially overlapped; and the spraying ranges of adjacent second nozzles are connected or partially overlapped.

[0008] Preferably, the first nozzle and the second nozzle are atomizing nozzles.

[0009] Preferably, the first liquid inlet pipe and the second liquid inlet pipe are connected to the absorbent configuration box via a second pressure pump, respectively.

[0010] Preferably, the liquid outlet pipe is further provided with a first pressure pump, and the first pressure pump is respectively connected to the first liquid inlet pipe and the second liquid inlet pipe through a reflux pipe; and a second valve is provided on the reflux pipe.

[0011] Preferably, the first liquid inlet pipe is provided with a third valve; the second liquid inlet pipe is provided with a fourth valve.

[0012] Preferably, the reflux pipe is also provided with a liquid recovery pipe; the liquid recovery pipe is provided with a fifth valve; the liquid recovery pipe is connected to the liquid storage tank through a pipe.

[0013] The second aspect of the present invention provides a method for absorbing carbon dioxide by the above system, comprising the following steps:

[0014] (1) A carbon dioxide absorbent and water are mixed to form a 25 wt% absorption liquid, and a gas containing carbon dioxide is introduced into the absorption box through an air inlet pipe;

[0015] (2) The absorption liquid is sprayed out through the atomizing nozzles on the first liquid inlet pipe and the second liquid inlet pipe, and the absorption liquid is fully mixed with carbon dioxide and finally falls into the liquid recovery pool;

[0016] (3) When the absorption liquid in the liquid recovery tank is full, the first valve, the second valve and the first pressure pump are opened to send the absorption liquid into the first liquid inlet pipe and the second liquid inlet pipe through the reflux pipe, and then spray out again to continue absorbing carbon dioxide;

[0017] (4) When the pH value of the absorption liquid in the liquid recovery tank is less than or equal to 7.5, close the second valve, open the fifth valve, discharge the absorption liquid through the liquid recovery pipe, and then recycle it.

[0018] Preferably, the carbon dioxide absorbent is a hyperbranched polyamine carbon dioxide absorbent, the structural formula of the hyperbranched polyamine carbon dioxide absorbent has a repeating structural unit of -AC- or -BC-, and the structural formulas of A, B, and C are as follows:

[0019]

[0020] R1, R2, R3, and R4 independently represent -Ar- or a C1-C8 unsubstituted or substituted alkyl group, wherein Ar is a divalent aromatic group; and n=0-4.

[0021] The preparation method of the hyperbranched polyamine carbon dioxide absorbent is:

[0022] (1) In an organic solvent, pentaerythritol or glycerol reacts with phosphorus tribromide to obtain tetrabromopentaerythritol or tribromoglycerol;

[0023] (2) In an organic solvent, tetrabromopentanyl alcohol or tribromoglycerol reacts with a compound of the general formula P1 in the presence of a base to obtain a compound having a structural formula A or B; the structural formula of the compound of the general formula P1 is as follows:

[0024] Wherein R represents -Ar- or C1-C8 unsubstituted or substituted alkyl;

[0025] (3) In an organic solvent, under the action of a reducing agent, a compound having the structural formula A or B reacts with a compound having the structural formula C to obtain a hyperbranched polyamine carbon dioxide absorber.

[0026] Preferably, the hyperbranched polyamine carbon dioxide absorbent absorbs carbon dioxide to obtain a carbon-rich fluid.

[0027] Beneficial effects of the present invention:

[0028] (1) The system of the present invention can not only improve the absorption rate of carbon dioxide, but also improve the utilization efficiency of the absorbent and reduce the absorption cost of carbon dioxide.

[0029] (2) The present invention uses a hyperbranched polyamine carbon dioxide absorbent as a material for absorbing carbon dioxide. After absorbing carbon dioxide, the hyperbranched polyamine carbon dioxide absorbent becomes a carbon-rich fluid and can also be used to improve oil recovery. The carbon dioxide can be stored in oil and gas fields, and the oil recovery rate can be improved, and the cost of carbon dioxide capture and storage technology (CCS) can be reduced. There is no need to separate the carbon dioxide in the absorbent separately, achieving multiple goals at one stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 : A schematic structural diagram of a first embodiment of the present invention;

[0031] Figure 2 : A schematic structural diagram of a second embodiment of the present invention;

[0032] Figure 3 : A schematic diagram of the structure of the absorption box in the first embodiment;

[0033] Figure 4 : A schematic diagram of the structure of the absorption box in the second embodiment;

[0034] Figure 5 : Schematic diagram of the connection mode between the first liquid spray pipe and the first liquid inlet pipe, and the connection mode between the second liquid spray pipe and the second liquid inlet pipe;

[0035] Wherein: 1. absorption box, 2. liquid recovery tank, 3. liquid outlet pipe, 4. first valve, 5. first liquid spray pipe, 6. first nozzle, 7. first rotating motor, 8. first sleeve pipe, 9. first liquid inlet pipe, 10. second liquid spray pipe, 11. second nozzle, 12. second rotating motor, 13. second sleeve pipe, 14. second liquid inlet pipe, 15. air inlet pipe, 16. air outlet, 17. agitator, 18. first booster pump, 19. reflux pipe, 20. second valve, 21. third valve, 22. fourth valve, 23. fifth valve, 24. liquid recovery pipe, 25. gas cooler, 26. absorbent configuration box, 27. water pipe, 28. absorbent pipe, 29. liquid storage tank, 30. second booster pump. DETAILED DESCRIPTION

[0036] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0037] As introduced in the background technology section, the traditional CO2 capture process is to convert gaseous CO2 into a solution state through the reaction of absorbent and CO2, and then decompose and analyze it through high temperature (>120℃), purify and compress it, and then store and transport it for sealing. This carbon dioxide capture and storage technology (CCS) is relatively expensive.

[0038] Based on this, the purpose of the present invention is to provide a method and an absorption system for absorbing carbon dioxide using a hyperbranched polyamine carbon dioxide absorbent. The present invention comprehensively considers the entire process of CO2 capture and utilization, and through the research and development of a new absorbent material: a hyperbranched polyamine carbon dioxide absorbent, the solution after the absorbent absorbs CO2, that is, the carbon-rich fluid, can be effectively utilized, combined with the secondary and tertiary oil recovery in the oil field development link, thereby removing the entire high-temperature analysis and gas compression system, greatly simplifying the absorption process, solving the problems faced by traditional processes, greatly reducing investment costs, and greatly improving operational stability. The CO2 capture facility is transformed into an oilfield chemical production device, and the "waste liquid" that absorbs CO2 is turned into treasure, which is used as a high-value-added oilfield chemical to be injected back into the oil reservoir, sealing CO2 while increasing oil recovery, which is a brand-new CCUS technology.

[0039] Since CO2 is heavier than air, the present invention sets a first liquid spray pipe 5 and a second liquid spray pipe 10 at the top and bottom of the absorption box 1, respectively, sets the air inlet of carbon dioxide between the first liquid spray pipe 5 and the second liquid spray pipe 10, sprays liquid through an atomizing nozzle, improves the absorption rate of carbon dioxide, and the absorption liquid after absorbing carbon dioxide becomes a carbon-rich fluid, which is finally discharged and recovered from the liquid recovery pool 2 and used as an oil displacement agent later. Other unabsorbed gases are discharged through the air outlet 16 at the top of the absorption box 1.

[0040] A carbon dioxide absorption system, such as Figure 1 and 3As shown, the first embodiment of the present invention is as follows: it includes an absorption box 1; a liquid recovery pool 2 is provided at the bottom of the absorption box 1, a liquid outlet pipe 3 is provided at the bottom of the liquid recovery pool 2, and a first valve 4 is provided on the liquid outlet pipe 3; a "T"-shaped first liquid spray pipe 5 is provided on the top of the absorption box 1, and a plurality of first nozzles 6 with openings facing downward are provided on the first liquid spray pipe 5; a first rotating motor 7 is provided above the absorption box 1, and the first rotating motor 7 is fixedly connected to the first liquid spray pipe 5; the top end of the first liquid spray pipe 5 extends into a first sleeve 8, and the other end of the first sleeve 8 is fixedly connected to a first liquid inlet pipe 9; a "T"-shaped second liquid spray pipe 10 is provided above the liquid recovery pool 2, and a plurality of second nozzles 11 with openings facing upward are provided on the second liquid spray pipe 10; The lower part of the second liquid spray pipe 10 is fixedly connected to the second rotating motor 12; the end of the second liquid spray pipe 10 extends into the second sleeve 13, and the other end of the second sleeve 13 is fixedly connected to the second liquid inlet pipe 14; the second liquid inlet pipe 14 passes through the side wall of the absorption box 1 and is connected to the outer wall; a plurality of air inlet pipes 15 are provided on the side wall of the absorption box 1, and the air inlet pipes 15 are located between the first liquid spray pipe 5 and the second liquid spray pipe 10; a plurality of air outlets 16 are provided on the top of the absorption box 1; the air inlet pipe 15 is connected to the gas cooler 25 through a pipeline; the first liquid inlet pipe 9 and the second liquid inlet pipe 14 are respectively connected to the absorbent configuration box 26 through pipelines, and the absorbent configuration box 26 is respectively provided with a water pipe 27 and an absorbent pipe 28; the liquid outlet pipe 3 is connected to the liquid storage tank 29 through a pipeline.

[0041] like Figure 2 As shown, the second embodiment of the present invention is: on the basis of the first embodiment, a plurality of agitators 17 are provided on the side walls of the bottom and top of the liquid recovery pool 2. The ranges of liquid spraying between adjacent first nozzles 6 are connected or partially overlapped; the ranges of liquid spraying between adjacent second nozzles 11 are connected or partially overlapped. The first nozzles 6 and the second nozzles 11 are atomizing nozzles. The first liquid inlet pipe 9 and the second liquid inlet pipe 14 are connected to the absorbent configuration box 26 through the second booster pump 30 respectively. The liquid outlet pipe 3 is also provided with a first booster pump 18, and the first booster pump 18 is respectively connected to the first liquid inlet pipe 9 and the second liquid inlet pipe 14 through a reflux pipe 19; the reflux pipe 19 is provided with a second valve 20. The first liquid inlet pipe 9 is provided with a third valve 21; the second liquid inlet pipe 14 is provided with a fourth valve 22. The reflux pipe 19 is also provided with a liquid recovery pipe 24; the liquid recovery pipe 24 is provided with a fifth valve 23; the liquid recovery pipe 24 is connected to the liquid storage tank 29 through a pipe.

[0042] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments.

[0043] The test materials used in the examples of the present invention are all conventional test materials in the art and can be purchased through commercial channels.

[0044] Example 1

[0045] Preparation of hyperbranched polyamine carbon dioxide absorbent:

[0046] The general formula is -AC- repeating unit, and R1=R2=R3=R4= Preparation of compound P4-1 with n=2;

[0047] The structural formula of P4-1 is:

[0048]

[0049] 1) Pentaerythritol (13.6 g, 0.1 mol) was dissolved in dry N,N-dimethylformamide (200 mL), and phosphorus tribromide (133 g, 0.5 mol) was added in batches at 25°C. After stirring for 20 minutes, the temperature was slowly raised to 125°C and reacted for 12 hours. After the reaction was completed, the reaction solution was poured into ice water (500 mL), and sodium hydroxide solution (0.2 mol L -1 ) was adjusted to pH 8, and the residue was filtered to obtain tetrabromopentylerythrin (24.6 g, 64%). 1 H NMR (CDCl3, 400MHz): δ3.20 (s, 8H). 13 C NMR(CDCl3,100MHz):δ146.1,37.9.HR-MS(MALDI):m / z[M] + cacld for C5H8Br4,383.7860; found,387.7319.

[0050] 2) Add tetrabromopentyl alcohol (19.2 g, 0.05 mol) and 4-hydroxybenzaldehyde (26.8 g, 0.220 mol) prepared in step 1) and potassium carbonate (41.4 g, 0.30 mol) to N,N-dimethylformamide (250 mL), heat to 100° C. and react for 16 hours. Pour the reaction solution into ice water (500 mL), and filter the residue to obtain intermediate product A-1 (22.9 g, 83%). 1 H NMR (CDCl3, 400MHz): δ3.82 (s, 8H), 7.17 (d, J = 8.0Hz, 8H), 7.78 (d, J = 8.0Hz, 8H), 10.02 (s, 4H). 13C NMR(CDCl3,100MHz): δ191.11,165.23,131.92,128.56,114.97,61.23,40.26.HR-MS(MALDI):m / z[M] + cacld for C33H28O8,552.1784; found,553.1790.

[0051] 3) The intermediate product A-1 (27.6 g, 0.05 mol) prepared in step 2) and C-1 (n = 2) triethylenetetramine (14.6 g, 0.10 mol) were added to methanol (100 mL), and sodium borohydride (7.6 g, 0.20 mol) was slowly added in batches at 0-10 ° C. After the addition, the reaction solution was heated to room temperature and the reaction was continued for 5 hours. The solvent was evaporated under reduced pressure, and the residue was dissolved in chloroform and filtered. The filtrate was evaporated under reduced pressure to obtain hyperbranched polyamine P4-1 (33.4 g, 86%). 1 H NMR (CDCl3, 400MHz): δ2.52-2.66 (m, 48H), 3.74 (s, 8H), 3.80 (s, 8H), 7.12 (d, J = 8.0Hz, 8H), 7.54 (d, J = 8.0Hz, 8H). 13 CNMR (CDCl3, 100MHz): δ157.71,156.63,131.82,130.26,127.17,114.20,61.23,52.33,51.20,49.12,48.25,41.26.

[0052] Example 2

[0053] (1) The carbon dioxide absorbent prepared in Example 1 and water were respectively sent into the absorbent preparation box through the absorbent pipe and the water pipe, and prepared into a 25 wt% absorption liquid.

[0054] The flue gas comes from the flue gas after desulfurization in the steel plant, and the sulfur content of the flue gas is 35mg / Nm 3 , carbon dioxide content is 10.6%, gas volume is 300000Nm 3 / h. The flue gas is pressurized to a slight positive pressure of 2000Pa and sent to the gas cooler 25, where the flue gas is cooled from 120°C to below 30°C, and the gas containing carbon dioxide is introduced into the absorption box through the air inlet pipe.

[0055] (2) Liquid-gas ratio 10L / m 3, send the configured absorption liquid into the first liquid inlet pipe and the second liquid inlet pipe through the second pressure pump, open the third valve and the fourth valve, spray the absorption liquid through the atomizing nozzles on the first spray pipe and the second spray pipe, start the first rotating motor and the second rotating motor, the first liquid inlet pipe and the second liquid inlet pipe rotate in the absorption box, the absorption liquid is fully mixed with carbon dioxide, and finally falls into the liquid recovery pool.

[0056] (3) When the absorption liquid in the liquid recovery tank is full, close the third valve and the fourth valve, open the first valve, the second valve and the first pressure pump, and send the absorption liquid into the first liquid inlet pipe and the second liquid inlet pipe through the reflux pipe, and spray it out again to continue absorbing carbon dioxide.

[0057] (4) When the pH value of the absorption liquid in the liquid recovery tank is equal to 7.5, the absorption liquid absorbs enough carbon dioxide to become a carbon-rich fluid. Close the second valve, open the fifth valve, and discharge the absorption liquid into the liquid storage tank through the liquid recovery pipe for recycling. The carbon-rich fluid is recovered and used as an oil displacement agent.

[0058] It has been calculated that the average content of carbon dioxide in the exhaust flue gas is 0.11% through real-time monitoring of the gas discharged from the outlet.

[0059] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for absorbing carbon dioxide using a carbon dioxide absorption system, characterized in that: The carbon dioxide absorption system comprises an absorption box; a liquid recovery pool is provided at the bottom of the absorption box, a liquid outlet pipe is provided at the bottom of the liquid recovery pool, and a first valve is provided on the liquid outlet pipe; a "T"-shaped first liquid spray pipe is provided at the top of the absorption box, and a plurality of first nozzles with openings facing downward are provided on the first liquid spray pipe; a first rotating motor is provided above the absorption box, and the first rotating motor is fixedly connected to the first liquid spray pipe; the top end of the first liquid spray pipe extends into the first sleeve, and the other end of the first sleeve is fixedly connected to the first liquid inlet pipe; a "T"-shaped second liquid spray pipe is provided above the liquid recovery pool, and a plurality of second nozzles with openings facing upward are provided on the second liquid spray pipe The nozzle comprises a nozzle; the lower part of the second liquid spray pipe is fixedly connected to the second rotating motor; the end of the second liquid spray pipe extends into the second sleeve, and the other end of the second sleeve is fixedly connected to the second liquid inlet pipe; the second liquid inlet pipe passes through the side wall of the absorption box and is connected to the outer wall; a plurality of air inlet pipes are arranged on the side wall of the absorption box, and the air inlet pipes are located between the first liquid spray pipe and the second liquid spray pipe; a plurality of air outlets are arranged on the top of the absorption box; the air inlet pipe is connected to the gas cooler through a pipeline; the first liquid inlet pipe and the second liquid inlet pipe are respectively connected to the absorbent configuration box through pipelines, and the absorbent configuration box is respectively provided with a water pipe and an absorbent pipe; the liquid outlet pipe is connected to the liquid storage tank through a pipeline; A plurality of agitators are provided on the side walls of the bottom and top of the liquid recovery tank; The spraying ranges of adjacent first nozzles are connected or partially overlapped; the spraying ranges of adjacent second nozzles are connected or partially overlapped; the first nozzle and the second nozzle are atomizing nozzles; The first liquid inlet pipe and the second liquid inlet pipe are respectively connected to the absorbent configuration box through a second pressure pump; The liquid outlet pipe is also provided with a first pressure pump, and the first pressure pump is connected to the first liquid inlet pipe and the second liquid inlet pipe respectively through a reflux pipe; the reflux pipe is provided with a second valve; The first liquid inlet pipe is provided with a third valve; the second liquid inlet pipe is provided with a fourth valve; The reflux pipeline is also provided with a liquid recovery pipe; the liquid recovery pipe is provided with a fifth valve; the liquid recovery pipe is connected to the liquid storage tank through a pipeline; The method comprises the following steps: (1) The carbon dioxide absorbent and water are respectively sent into the absorbent preparation box through the absorbent pipe and the water pipe to prepare a 25wt% absorption liquid. The gas containing carbon dioxide is sent into the gas cooler to cool the gas to below 30°C, and the gas containing carbon dioxide is introduced into the absorption box through the air inlet pipe; The carbon dioxide absorbent is a hyperbranched polyamine carbon dioxide absorbent, and the structural formula of the hyperbranched polyamine carbon dioxide absorbent has a repeating structural unit of -AC- or -BC-, and the structural formulas of A, B, and C are as follows: ； R1, R2, R3, R4 each independently represent -Ar- or C1~C8 unsubstituted or substituted alkyl, wherein Ar is a divalent aromatic group; n=0~4; (2) The prepared absorption liquid is sent into the first liquid inlet pipe and the second liquid inlet pipe through the second pressure pump, and sprayed out through the atomizing nozzles on the first liquid spray pipe and the second liquid spray pipe. The absorption liquid is fully mixed with carbon dioxide and finally falls into the liquid recovery pool; (3) When the absorption liquid in the liquid recovery tank is full, the first valve, the second valve and the first pressure pump are opened to send the absorption liquid into the first liquid inlet pipe and the second liquid inlet pipe through the reflux pipe, and then spray out again to continue absorbing carbon dioxide; (4) When the pH value of the absorption liquid in the liquid recovery tank is less than or equal to 7.5, close the second valve, open the fifth valve, and discharge the absorption liquid into the liquid storage tank through the liquid recovery pipe for recycling.

2. The method according to claim 1, characterized in that The hyperbranched polyamine carbon dioxide absorbent absorbs carbon dioxide to obtain a carbon-rich fluid.

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