A method of inhibiting dissolved oxygen in a carbon capture system

Abstract

The application discloses a method for inhibiting dissolved oxygen in a carbon capture system, and belongs to the technical field of carbon dioxide capture, and comprises the following steps: detecting a dissolved oxygen parameter in rich liquid, and calculating a real-time dissolved oxygen content in the rich liquid in real time; obtaining lean liquid, dissolving a sacrificial antioxidant in the lean liquid to obtain a sacrificial antioxidant solution; obtaining flue gas oxygen load, calculating a basic feeding amount of the sacrificial antioxidant solution according to a preset feeding ratio, feeding the sacrificial antioxidant solution at the basic feeding amount at a preset feeding point, obtaining rich liquid after preliminary deoxygenation, dynamically adjusting a real-time feeding amount of the sacrificial antioxidant solution based on the real-time dissolved oxygen content in the rich liquid after preliminary deoxygenation and system load, and obtaining deoxygenated rich liquid; and performing carbon dioxide resolution treatment on the deoxygenated rich liquid to obtain target product CO2. The method provided by the application can effectively inhibit dissolved oxygen in the carbon capture system, improve the carbon capture efficiency, and reduce equipment maintenance cost.

Description

Technical Field

[0001] This invention belongs to the field of carbon dioxide capture technology, specifically relating to a method for suppressing dissolved oxygen in a carbon capture system. Background Technology

[0002] Chemical absorption is currently the most mature CO2 capture technology in industrial applications. Its core process is based on the chemical adsorption of CO2 in flue gas by an amine-based absorbent (such as monoethanolamine or multi-component amine systems) in an absorption tower to generate a rich solution. Subsequently, high-purity CO2 is released and the lean solution is regenerated in a desorption tower through high-temperature heating. Flue gas typically contains 5-10 vol% oxygen, which dissolves into the absorbent and is transported to the desorption tower with the rich solution. Under the combined effects of high temperature and oxygen, the absorbent undergoes significant oxidative and thermal degradation, producing byproducts such as thermally stable salts, aldehydes, or organic acids. This leads to problems such as absorbent loss, decreased efficiency, equipment corrosion, and increased operation and maintenance costs.

[0003] To inhibit absorbent degradation, the industry generally uses non-sacrificial antioxidants / stabilizers, mainly including metal ion chelators, phenolic stabilizers, amine free radical blockers, and composite corrosion inhibitors. These stabilizers are designed to be non-consumable and remain in the circulating system for a long time, avoiding sacrificial antioxidant routes. Patent CN104226079A discloses an antioxidant for organic amine decarbonization solutions, which involves adding a metal chelator and an organometallic complex composite antioxidant to the organic amine decarbonization solution. The metal chelator reduces the content of free metal ions and inhibits catalytic oxidation; the organometallic complex blocks the oxidation reaction chain; the two work synergistically to inhibit the oxidative degradation of the amine solution. In this system, the agent is added once and remains in the circulating system for a long time, without undergoing a stoichiometric consumption reaction with oxygen. Patent CN116983822A discloses a compound antioxidant and its application. This patent uses an antioxidant composed of a free radical scavenger, an oxygen scavenger, and a metal ion passivator, added to an amine solution to inhibit oxidative degradation. Stability is achieved by blocking free radicals, passivating metal ions, and assisting oxygen isolation, with a non-sacrificial, long-lasting retention mechanism throughout. Patent CN106237792A discloses an absorbent with antioxidant properties for removing acidic gases, using a phenolic antioxidant (dendritic macromolecular phenol). These existing technologies mostly involve one-time addition to a lean solution and long-term retention, failing to address dissolved oxygen at its source, lacking targeted removal of dissolved oxygen and continuous precise addition design. Furthermore, the treated products are mostly complexes / stabilized salts, easily accumulating, reducing absorption capacity, and exacerbating foaming and corrosion. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for suppressing dissolved oxygen in a carbon capture system. This invention uses a sacrificial antioxidant, which can improve the oxidative degradation rate of amine liquid, while the product is clean and residue-free, green and environmentally friendly, effectively improving the service life of the equipment and reducing waste liquid discharge and maintenance costs.

[0005] This invention provides the following technical solution: A method for suppressing dissolved oxygen in a carbon capture system is provided, comprising: Detect dissolved oxygen parameters in the rich solution and calculate the real-time dissolved oxygen content in the rich solution; Obtain a lean solution, dissolve the sacrificial antioxidant in the lean solution to obtain a sacrificial antioxidant solution; Obtain the flue gas oxygen load, calculate the basic dosage of the sacrificial antioxidant solution according to the preset dosage ratio, and add it at the preset dosage point at the basic dosage to obtain a rich solution with preliminary deoxygenation. Based on the real-time dissolved oxygen content and system load in the rich solution with preliminary deoxygenation, dynamically adjust the real-time dosage of the sacrificial antioxidant solution to obtain a rich solution with deoxygenation. The deoxygenated rich liquid was subjected to carbon dioxide desorption treatment to obtain the target product CO2.

[0006] Furthermore, the step of detecting dissolved oxygen parameters in the rich solution and calculating the real-time dissolved oxygen content in the rich solution includes: detecting dissolved oxygen parameters in the rich solution, the dissolved oxygen parameters including dissolved oxygen concentration, flow rate and temperature, and calculating the real-time dissolved oxygen content in the rich solution, wherein the real-time dissolved oxygen content is the amount of oxygen moles per unit time.

[0007] Furthermore, the mass fraction of dissolved oxygen in the sacrificial antioxidant is 5-20 wt%.

[0008] Furthermore, the sacrificial antioxidant includes any one or more of isoascorbic acid, sodium isoascorbate, carbazide, oxime compounds, hydroxylamine derivatives, aminoguanidine salts, or sulfur-containing antioxidants; The sulfur-containing antioxidant includes any one or more of sodium sulfite, sodium metabisulfite, sodium bisulfite, or sodium dithionite.

[0009] Furthermore, when the sacrificial antioxidant is a sulfur-containing antioxidant, the method for inhibiting dissolved oxygen in the carbon capture system further includes: performing sulfate removal treatment on the deoxygenated rich solution and / or the target product.

[0010] Furthermore, the preset injection points include the turbulent liquid section of the rich liquid pipeline at the absorber outlet, the rich liquid pump outlet section, the inlet side of the lean and rich liquid heat exchanger, and the inlet side of the desorption tower feed inlet.

[0011] Furthermore, the preset dosage ratio is the ratio of the molar amount of the sacrificial antioxidant administered per unit time to the real-time dissolved oxygen content, and the ratio is 1.1 to 1.25 times the stoichiometric ratio corresponding to the complete reaction of the sacrificial antioxidant with oxygen.

[0012] Furthermore, the sacrificial antioxidant solution can be delivered via pressure atomization spraying, Venturi spraying, or online ultrasonic enhanced mixing, or any one or more of these methods.

[0013] Furthermore, the concentration of the sacrificial antioxidant solution is 100~500 mg / L.

[0014] Furthermore, the process of obtaining flue gas oxygen load, calculating the basic dosage of sacrificial antioxidant solution based on a preset dosage ratio, and dispensing it at a preset dosage point at the basic dosage to obtain a pre-deoxygenated rich solution, and dynamically adjusting the real-time dosage of sacrificial antioxidant solution based on the real-time dissolved oxygen content and system load in the pre-deoxygenated rich solution to obtain a deoxygenated rich solution, includes: The oxygen content and flow rate of the flue gas at the inlet of the carbon capture system are monitored in real time, the flue gas oxygen load is calculated, and the basic dosage of the sacrificial antioxidant solution is determined based on the preset dosage ratio and flue gas oxygen load. The solution is then added at the preset dosage point according to the basic dosage to obtain a rich solution with preliminary deoxygenation. The real-time dissolved oxygen content in the pre-deoxygenated rich solution is detected. Based on the preset dissolved oxygen target value, the deviation of dissolved oxygen in the pre-deoxygenated rich solution is calculated. The deviation of dissolved oxygen is corrected based on the amount of CO2 desorption, and the real-time compensation dosage of the sacrificial antioxidant solution is obtained. The base dosage and the real-time compensation dosage are added together to obtain the final real-time dosage, which is then applied at the preset dosage points to obtain deoxygenated rich solution.

[0015] Compared with the prior art, the beneficial effects of the present invention are: (1) This invention employs a sacrificial antioxidant. Based on real-time monitoring of dissolved oxygen content and dynamic adjustment of load, the content of the sacrificial antioxidant is adjusted to ensure that it can fully react with dissolved oxygen in the rich solution, blocking and degrading dissolved oxygen at the source. The selected preset dosing point is set before the high-temperature desorption section, avoiding the oxidative and thermal degradation of dissolved oxygen in the rich solution in the high-temperature desorption section, reducing competition with CO2, and ensuring the absorption-desorption balance of CO2. This improves the CO2 capture efficiency. (2) This invention uses the lean liquid of the system as a reagent to dissolve the drug without adding water, thus not increasing the energy consumption of desorption. This invention can flexibly select non-sulfur-containing or sulfur-containing sacrificial antioxidants according to the actual working conditions. When non-sulfur-containing sacrificial antioxidants (such as isoascorbic acid, sodium isoascorbate, hydroxylamine derivatives or aminoguanidine salts, etc.) are selected, the main products after their reaction with dissolved oxygen are water, nitrogen, carbon dioxide or soluble organic acids. These products can be discharged with the gas phase or remain in the aqueous phase without producing thermally stable salts under the high temperature environment of the stripping tower. It is green, clean and salt-free. When sulfur-containing sacrificial antioxidants (such as sodium sulfite, sodium metabisulfite, sodium bisulfite or sodium dithionite, etc.) are selected, this invention sets a sulfate removal device in the carbon capture system to remove the sulfate in the sulfate-containing rich liquid before it enters the stripping tower, so as to avoid the salts from entering the circulation system, or remove the sulfate at the outlet of the stripping tower to achieve the clean operation effect of "no thermally stable salt accumulation" in the system. (3) The method provided by the present invention only adds a monitoring and dosing unit, which can be directly used to modify existing devices. In addition, the method provided by the present invention can extend the life of the absorbent and reduce waste liquid discharge and maintenance costs. Attached Figure Description

[0016] Figure 1 This is a flowchart of the method for suppressing dissolved oxygen in the carbon capture system of the present invention. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0018] In the description of this invention, unless otherwise stated, "a plurality of" means two or more. The terms "comprising," "including," "having," "containing," etc., as used herein are open-ended, meaning they include but are not limited to.

[0019] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0020] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0021] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0022] Example 1

[0023] This embodiment provides a method for suppressing dissolved oxygen in a carbon capture system, comprising the following steps.

[0024] S1. Detect dissolved oxygen parameters in the rich solution and calculate the real-time dissolved oxygen content in the rich solution.

[0025] Dissolved oxygen parameters in the enriched solution are detected, including dissolved oxygen concentration, flow rate, and temperature. The real-time dissolved oxygen content in the enriched solution is calculated, which is the amount of oxygen moles per unit time.

[0026] S2. Obtain a lean solution by dissolving the sacrificial antioxidant in the lean solution to obtain a sacrificial antioxidant solution.

[0027] In some possible embodiments, the sacrificial antioxidant includes sulfur-containing and non-sulfur-containing antioxidants. Non-sulfur-containing antioxidants include any one or more of isoascorbic acid, sodium isoascorbate, carbazide, oxime compounds, hydroxylamine derivatives, or aminoguanidine salts. Sulfur-containing antioxidants include any one or more of sodium sulfite, sodium metabisulfite, sodium bisulfite, or sodium dithionite. When a sulfur-containing antioxidant is used as the sacrificial antioxidant, a sulfate removal device needs to be added to the carbon capture system to remove sulfate from the deoxygenated rich solution and / or target product. In some possible embodiments, a sulfate removal device is installed downstream of the preset dosing point or at the outlet of the stripping tower to remove the sulfate generated in the reaction, avoiding pipeline corrosion and blockage caused by salt accumulation. The sulfate removal device can be an ion exchange resin bed, an electrodialysis unit, or a precipitation filtration unit. The preset dosage ratio is the ratio of the molar amount of sacrificial antioxidant added per unit time to the real-time dissolved oxygen content, which is 1.1 to 1.25 times the stoichiometric ratio of the sacrificial antioxidant to oxygen for complete reaction. This ensures that the sacrificial antioxidant is slightly in excess of the oxygen in the rich solution, so that it can completely react with the dissolved oxygen in the rich solution.

[0028] In some possible embodiments, the sacrificial antioxidant solution may also contain metal chelates to synergistically suppress dissolved oxygen in the rich solution. Metal chelates include any one or more of iron-based chelates, cobalt-based chelates, cerium-based chelates, or copper-based chelates.

[0029] S3. Obtain the oxygen load of the flue gas, calculate the basic dosage of the sacrificial antioxidant solution according to the preset dosage ratio, and add it at the preset dosage point at the basic dosage to obtain a rich solution with preliminary deoxygenation. Based on the real-time dissolved oxygen content and system load in the rich solution with preliminary deoxygenation, dynamically adjust the real-time dosage of the sacrificial antioxidant solution to obtain a rich solution with deoxygenation.

[0030] In some possible embodiments, the sacrificial antioxidant solution is delivered via pressure atomization, venturi injection, or online ultrasonic-enhanced mixing, or a combination thereof. A static mixer can also be installed downstream of the preset delivery point to ensure uniform mixing of the sacrificial antioxidant solution with dissolved oxygen in the rich solution. In one possible embodiment, a static mixer is used. The static mixer is installed on the rich solution delivery pipeline and fixed between two flanges via a flange connection, positioned immediately downstream of the preset delivery point. The mixer contains multiple fixed flow dividers, which repeatedly shear, divide, rotate, and merge the rich solution and the sacrificial antioxidant solution as they flow through, achieving rapid and uniform mixing. Installation is not directionally restricted and can be horizontal, vertical, or other combinations thereof depending on the pipeline layout.

[0031] In one possible embodiment, the dosing method employs high-pressure atomized injection, with a static mixer positioned downstream of the dosing point to ensure thorough mixing of the sacrificial antioxidant with the rich solution. The mixed rich solution then passes through a predetermined length of retention pipe to guarantee sufficient reaction contact time, resulting in a deoxygenated rich solution.

[0032] In one possible embodiment, the delivery method employs a Venturi jetting approach, with a Venturi injector connected in series in the rich solution delivery pipeline. The upstream end is the high-pressure rich solution inlet, and the downstream end is the mixed solution outlet. The high-pressure rich solution is accelerated through the nozzle to form a high-speed jet, creating a low-pressure zone at the throat that draws in the sacrificial antioxidant solution. The high-speed jet and the agent undergo vigorous mixing within the throat and diffuser section. This method requires no external power, utilizing the residual pressure at the rich solution pump outlet, and is particularly suitable for high-pressure delivery points such as the pump outlet section.

[0033] In one possible embodiment, an online ultrasonic-enhanced mixing method is employed. An ultrasonic transducer is installed in the pipeline section downstream of a predetermined dosing point. The transducer is fixed to the outside of the pipeline via a flange and connected to an ultrasonic generator. The cavitation effect generated by the ultrasonic field disperses the antioxidant solution into micron-sized droplets, greatly increasing the interfacial contact area with the rich liquid and achieving rapid and thorough mixing. This method is suitable for operating conditions requiring high mixing uniformity, or as a supplementary enhancement to static mixers.

[0034] In some possible embodiments, the preset injection points include the turbulent liquid section of the rich liquid section at the absorber outlet, the rich liquid pump outlet section, the inlet side of the lean-rich liquid heat exchanger, and the inlet side of the desorption tower feed inlet. This allows it to react rapidly with dissolved oxygen before the absorbent, completely removing oxygen before the rich liquid enters the high-temperature desorption tower; the injected sacrificial antioxidant does not react with amine molecules and does not affect the CO2 load. In this invention, the antioxidant is dissolved in a lean liquid system without the need for an aqueous solution, thus not affecting the water balance. The reaction products are water or gas, which can be discharged with the tail gas without residue or affecting the main process.

[0035] In some possible embodiments, the method for dynamically controlling the real-time dosage of the sacrificial antioxidant solution employs strategies such as flue gas oxygen content feedforward control, primary coarse dosing and secondary fine-tuning series protection, including the following steps.

[0036] 1. Feedforward control of flue gas oxygen content

[0037] An oxygen content analyzer and flow meter are installed at the flue gas inlet to monitor the oxygen content (C) of the flue gas at the carbon capture system in real time. 氧 and flue gas flow rate Q 烟气 Calculate the flue gas oxygen load, where the flue gas oxygen load L = C. 氧 ×Q 烟气The basic dosage of the sacrificial antioxidant solution is calculated. The core function of feedforward control is to respond in advance and compensate for the lag of feedback control. The feedforward coefficient K = 0.8~1.2 and the utilization rate of sacrificial antioxidant η = 0.85~0.95.

[0038] 2. Series protection between primary coarse adjustment and secondary fine adjustment

[0039] Using the feedforward-calculated baseline as the master setpoint, a primary coarse feed is performed at 1.0 to 1.2 times the theoretical oxygen demand, with a response time of 5 to 30 seconds, ensuring that the supply is maintained near the target under steady-state conditions to obtain a pre-deoxygenated rich solution.

[0040] A dissolved oxygen sensor was used to detect the real-time dissolved oxygen (DO) content in the pre-deoxygenated rich solution. real According to the preset dissolved oxygen target value DO target (0.3~0.5 mg / L) Calculate the deviation ΔDO of dissolved oxygen in the initially deoxygenated rich solution. Introduce the system load (CO2 desorption) to correct the deviation of dissolved oxygen. The deviation is calculated by the proportional-integral-derivative (PID) algorithm to generate the real-time compensation dosage, which is superimposed on the first-level coarse dosage to obtain the final real-time dosage. The dosage is then delivered at the preset dosage point to obtain the deoxygenated rich solution. Second-level fine adjustment is performed, with a response time of 1~5 seconds.

[0041] The delivery method of this invention adopts a coordinated mechanism of series protection. First, a primary coarse delivery is performed to "guarantee the minimum level" so that basic deoxygenation is maintained even if the feedback signal fails. Then, a secondary fine-tuning is performed to "guarantee the accuracy" so that fluctuations are compensated for. The two are connected in series to ensure deoxygenation accuracy and system robustness.

[0042] S4. The deoxygenated rich liquid is subjected to carbon dioxide desorption treatment to obtain the target product CO2.

[0043] In this invention, the deoxygenated rich liquid enters the desorption tower for CO2 desorption; the reaction products (H2O, N2, CO2, etc.) are discharged with the desorption gas / tower top tail gas, with no harmful residues or by-product accumulation.

[0044] S5. The regenerated lean liquor after being treated by the desorption tower is returned to the absorption tower for recycling, and dissolved oxygen is degraded again based on the above steps.

[0045] This invention ensures that oxygen is removed before the rich liquid enters the high-temperature desorption section, so as not to compete with CO2 and not to affect the absorption-desorption balance. The oxidative degradation rate of amine liquid is reduced by 60-90%. In addition, this invention can extend the life of absorbent by 2-5 times and reduce waste liquid discharge and maintenance costs.

[0046] Example 2

[0047] Based on the method provided in Example 1, this example uses sodium isoascorbate as a sacrificial antioxidant, and prepares a solution with a concentration of 300 mg / L using lean solution as the solvent. The molar ratio (antioxidant: dissolved oxygen) is 2.2:1. After conversion, the actual mass ratio of the sacrificial antioxidant to O2 is approximately 13.62:1, which is greater than the stoichiometric ratio for complete reaction of sodium isoascorbate and oxygen, ensuring that sodium isoascorbate is added in excess.

[0048] In this embodiment, the preset injection point is the turbulent region at the outlet of the rich solution pump. The isoascorbic acid solution is injected using a high-pressure atomization injection method, and a static mixer is set downstream of the preset injection point to enhance mixing.

[0049] Example 3

[0050] Based on the method provided in Example 1, this example uses sodium sulfite as a sacrificial antioxidant and prepares a solution with a concentration of 300 mg / L using lean solution as the solvent. The molar ratio (antioxidant: dissolved oxygen) is 2.2:1. After conversion, the actual mass ratio of antioxidant to O2 is approximately 8.66:1, which is greater than the stoichiometric ratio for complete reaction of sodium sulfite and oxygen, ensuring that sodium sulfite is added in excess.

[0051] In this embodiment, the preset injection point is the turbulent section of the rich liquid section at the outlet of the absorption tower. The injection is carried out by high-pressure atomization injection. An ion exchange resin bed is set downstream of the injection point as a sulfate removal device.

[0052] Comparative Example 1

[0053] This comparative example follows the same method as Example 1, except that isoascorbic acid is not added.

[0054] Comparative Example 2

[0055] The method used in this comparative example is the same as that in Example 2, except that sodium sulfite is not added.

[0056] The dissolved oxygen levels in the enriched solutions after deoxygenation in Examples 2 and 3 were measured. The results showed that in Example 2, the residual dissolved oxygen in the enriched solution decreased from 4.2 mg / L to below 0.3 mg / L, with a deoxygenation rate of over 92%. In Example 3, the residual dissolved oxygen in the enriched solution decreased from 3.8 mg / L to below 0.5 mg / L, with a deoxygenation rate of over 87%.

[0057] Accelerated oxidation experiments were conducted on Example 2 and Comparative Example 1 for 30 consecutive days. The results showed that the amine oxidation degradation rate of monoethanolamine (MEA) in Comparative Example 1 was 7.33%, while the amine oxidation degradation rate of Example 2 was reduced to below 1.5% after the addition of sodium isoascorbate. The amine oxidation degradation rate was reduced by about 80%, and the reaction products were dehydroisoascorbic acid and water. No heat-stable salts were produced, which is green and environmentally friendly, and showed a significant inhibitory effect on amine oxidation degradation.

[0058] Both Example 3 and Comparative Example 2 were subjected to the same accelerated oxidation experiment. The results showed that the MEA degradation rate of Comparative Example 2 was 7.60 × 10⁻⁶. -4 kmol / m 3 •h, while in Example 3, the addition of sodium sulfite reduced it to 1.2 × 10. -4 kmol / m 3 Below 1 hour, the amine solution oxidation degradation rate decreases by approximately 84%. The sodium sulfate generated in the reaction is removed through an ion exchange resin bed, achieving a removal rate of over 95%, thus preventing salt accumulation within the system.

[0059] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for suppressing dissolved oxygen in a carbon capture system, characterized in that, include: Detect dissolved oxygen parameters in the rich solution and calculate the real-time dissolved oxygen content in the rich solution; Obtain a lean solution, dissolve the sacrificial antioxidant in the lean solution to obtain a sacrificial antioxidant solution; Obtain the flue gas oxygen load, calculate the basic dosage of the sacrificial antioxidant solution according to the preset dosage ratio, and add it at the preset dosage point at the basic dosage to obtain a rich solution with preliminary deoxygenation. Based on the real-time dissolved oxygen content and system load in the rich solution with preliminary deoxygenation, dynamically adjust the real-time dosage of the sacrificial antioxidant solution to obtain a rich solution with deoxygenation. The deoxygenated rich liquid was subjected to carbon dioxide desorption treatment to obtain the target product CO2.

2. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The detection of dissolved oxygen parameters in the rich solution and the real-time calculation of the dissolved oxygen content in the rich solution include: The dissolved oxygen parameters in the rich solution are detected, including the dissolved oxygen concentration, flow rate and temperature, and the real-time dissolved oxygen content in the rich solution is calculated, wherein the real-time dissolved oxygen content is the amount of oxygen moles per unit time.

3. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The mass fraction of dissolved oxygen in the sacrificial antioxidant is 5-20 wt%.

4. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The sacrificial antioxidants include any one or more of isoascorbic acid, sodium isoascorbate, carbazide, oxime compounds, hydroxylamine derivatives, aminoguanidine salts, or sulfur-containing antioxidants. The sulfur-containing antioxidant includes any one or more of sodium sulfite, sodium metabisulfite, sodium bisulfite, or sodium dithionite.

5. The method for suppressing dissolved oxygen in the carbon capture system according to claim 4, characterized in that, When the sacrificial antioxidant is a sulfur-containing antioxidant, the method for inhibiting dissolved oxygen in the carbon capture system further includes: performing sulfate removal treatment on the deoxygenated rich solution and / or the target product.

6. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The preset injection points include the turbulent liquid section of the rich liquid pipeline at the absorber outlet, the rich liquid pump outlet section, the inlet side of the lean and rich liquid heat exchanger, and the inlet side of the desorption tower feed inlet.

7. The method for suppressing dissolved oxygen in the carbon capture system according to claim 2, characterized in that, The preset dosage ratio is the ratio of the molar amount of the sacrificial antioxidant administered per unit time to the real-time dissolved oxygen content, and the ratio is 1.1 to 1.25 times the stoichiometric ratio corresponding to the complete reaction of the sacrificial antioxidant with oxygen.

8. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The sacrificial antioxidant solution can be delivered via pressure atomization, venturi spraying, or online ultrasonic-enhanced mixing, or any one or more of these methods.

9. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The concentration of the sacrificial antioxidant solution is 100~500 mg / L.

10. The method for suppressing dissolved oxygen in the carbon capture system according to claim 1, characterized in that, The process of obtaining flue gas oxygen load involves calculating the basic dosage of sacrificial antioxidant solution based on a preset dosage ratio, and then dispensing it at a preset dosage point at the basic dosage to obtain a pre-deoxygenated rich solution. Based on the real-time dissolved oxygen content and system load in the pre-deoxygenated rich solution, the real-time dosage of the sacrificial antioxidant solution is dynamically adjusted to obtain a deoxygenated rich solution. This process includes: The oxygen content and flow rate of the flue gas at the inlet of the carbon capture system are monitored in real time, the flue gas oxygen load is calculated, and the basic dosage of the sacrificial antioxidant solution is determined based on the preset dosage ratio and flue gas oxygen load. The solution is then added at the preset dosage point according to the basic dosage to obtain a rich solution with preliminary deoxygenation. The real-time dissolved oxygen content in the pre-deoxygenated rich solution is detected. Based on the preset dissolved oxygen target value, the deviation of dissolved oxygen in the pre-deoxygenated rich solution is calculated. The deviation of dissolved oxygen is corrected based on the amount of CO2 desorption, and the real-time compensation dosage of the sacrificial antioxidant solution is obtained. The base dosage and the real-time compensation dosage are added together to obtain the final real-time dosage, which is then applied at the preset dosage points to obtain deoxygenated rich solution.

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