A system for recycling a desulfurization and decarburization absorbent and a method for using and regulating the same

Abstract

The present application relates to a kind of desulfurization decarburization absorbent recycling system and its use and flexible control method, system includes the partition absorption tower and absorption agent high-efficiency capture recycling absorption pollutant integrated device being interconnected, partition absorption tower includes by lower and upper sequentially arranged desulfurization zone, first decarburization zone, second decarburization zone and tower top demisting device, desulfurization zone is connected with desulfurization absorbent pool, first decarburization zone is connected with first decarburization absorbent pool, second decarburization zone is connected with second decarburization absorbent pool;Desulfurization absorbent pool, first decarburization absorbent pool, second decarburization absorbent pool are connected with amine or ammonia pool respectively.The present application guarantees that desulfurization meets ultra-low emission requirement, system absorbent loss rate can be reduced by more than 95%, gaseous ammonia or amine, aerosol removal efficiency is more than 99%, decarburization efficiency can be promoted to more than 95%, even can reach 99%, while it can reduce system operating cost by more than 25%.

Description

Technical Field

[0001] This invention belongs to the field of air pollution control and energy conservation and emission reduction technology, specifically relating to a desulfurization and decarbonization absorbent reuse system and its use and control method. Background Technology

[0002] Pollutants (SO2, SO3, NO) generated during industrial production processes such as power generation and steelmaking due to the use of fossil fuels. x PM2.5 (PM2.5, heavy metals, etc.) and CO2 are important causes of air pollution, the greenhouse effect and climate change.

[0003] Chemical absorption is widely used in pollutant treatment (limestone-gypsum desulfurization, ammonia desulfurization, etc.) and CO2 post-combustion capture (organic amine decarbonization, ammonia decarbonization, etc.), and is currently the most commercially viable method for pollution reduction and carbon reduction. Furthermore, the ammonia or amine absorbents used in desulfurization and decarbonization share a high degree of interchangeability in absorption mechanisms and technologies, which also provides the possibility for the integration of desulfurization and decarbonization technologies. However, the current cost of low-concentration carbon capture in China is relatively high (300-600 RMB / t(CO2)), with a significant proportion of the cost being absorbent loss due to the volatilization and escape of ammonia or amine absorbents (for monoethanolamine decarbonization, the loss is approximately 0.5-0.8 kg MEA / t(CO2)). The escaped absorbent is in the form of gaseous ammonia or amine (concentration 10...). 2 ~10 4 ppm) and aerosols (concentration 10) 2 ~10 3 mg / m 3 Emissions in the form of [unspecified form] cause serious secondary pollution and affect the stable operation of the system. Therefore, reducing the escape and loss of absorbents in the chemical absorption desulfurization and decarbonization process and improving the efficiency of absorbent reuse are the key points of current technological development.

[0004] Patent CN 104707451 A discloses a method for carbon capture and chemical synthesis from flue gas using ammonia. The method uses ammonia water as an absorbent to capture CO2 from the flue gas and sodium sulfate as a conversion medium to produce chemical products such as sodium carbonate and sodium bicarbonate. However, simply washing the ammonia-containing tail gas after decarbonization results in a significant amount of ammonia escaping.

[0005] Patent CN 114345098 A proposes a method and system for inhibiting the decomposition of CO2 capture absorbents and achieving efficient pollution reduction. This method captures escaped amine absorbents through water washing and electrostatic demisting. However, the entire process uses demineralized water as the absorbent recovery medium, inevitably diluting the recovered absorbent and making it difficult to directly reuse it.

[0006] Patent CN 114917743 A establishes a device and method for controlling ammonia escape in an ammonia-based decarbonization system. The method absorbs escaped gaseous ammonia using process water, acidic ammonium sulfate solution, and acidic washing liquid, and then sends the absorbed liquid to the decarbonization and desulfurization circulation tanks. However, the multi-spray tower design used in this method occupies a large area, requiring reserved space for at least three spray towers, which is not conducive to the modification of existing flue gas treatment systems. Secondly, its ability to recover aerosol absorbent is limited, and direct reuse in the desulfurization and decarbonization circulation tanks will cause dilution and water balance problems, leading to continuous moisture accumulation in the system and affecting efficient desulfurization and decarbonization and stable system operation.

[0007] Therefore, existing technologies still have practical problems such as large absorbent loss, difficulty in controlling secondary pollution, and difficulty in achieving water and material balance in desulfurization and decarbonization systems. There is an urgent need to develop new technologies for reducing absorbent loss and effectively reusing it. Summary of the Invention

[0008] In order to overcome the shortcomings of the existing technology, the present invention provides a desulfurization and decarbonization absorbent recycling system and its use and control method.

[0009] The technical solution adopted in this invention is as follows:

[0010] A desulfurization and decarbonization absorbent reuse system includes interconnected partitioned absorption towers and an integrated device for high-efficiency capture, reuse, and absorption of pollutants. The partitioned absorption towers include, from bottom to top, a desulfurization zone, a first decarbonization zone, a second decarbonization zone, and a tower top demister. The desulfurization zone is connected to a desulfurization absorbent pool, the first decarbonization zone is connected to a first decarbonization absorbent pool, and the second decarbonization zone is connected to a second decarbonization absorbent pool. The desulfurization absorbent pool, the first decarbonization absorbent pool, and the second decarbonization absorbent pool are respectively connected to an amine replenishment pool or an ammonia pool.

[0011] The integrated device for efficient collection and reuse of absorbent pollutants includes, from bottom to top, a flue gas desulfurization and cooling section, a recovered absorbent enrichment tank, a first zoned high-efficiency scrubbing section for absorbent, a second zoned high-efficiency scrubbing section for absorbent, and an ion wind flushing charged collection section. The recovered absorbent enrichment tank is connected to the first zoned high-efficiency scrubbing section, the second zoned high-efficiency scrubbing section for absorbent, the ion wind flushing charged collection section, the flue gas desulfurization and cooling section, and the tower top demister. The desulfurization absorbent tank is connected to the recovered absorbent enrichment tank.

[0012] Preferably, the ion wind scouring charged collection section is arranged in a honeycomb tube array, and a snowflake-type ion wind scouring enhancement electrode is used in a single tube. The snowflake-type ion wind scouring enhancement electrode is placed at the geometric center of the collection tube, wherein the electrode tip is perpendicular to the tube wall (i.e., the collection plate) of the collection tube (the tip is perpendicular to the hexagonal tube wall).

[0013] As the length of the electrode tip increases, the discharge intensity increases, but the ion diffusion range generated by the tip discharge narrows and the current density on both sides of the tip decreases. Therefore, the preferred length of the electrode tip is 10~15mm.

[0014] As the spacing between electrode needles increases, the discharge intensity increases, and the breakdown voltage does not decrease significantly with the increase in the total number of needles. However, the current provided by each needle gradually decreases, resulting in a maximum decrease in peak current density and reduced tip utilization. Therefore, a needle spacing of 20-50 mm is preferred. For the ion wind scouring charged collection section, a novel snowflake-shaped ion wind scouring enhanced electrode was designed and developed. Through the coupling and regulation of ion wind and corona discharge, the discharge intensity of the honeycomb charged collection is improved, significantly increasing the aerosol collection efficiency, with an aerosol removal efficiency of over 95%. The ion wind scouring enhanced electrode used in the ion wind scouring charged collection section achieves high-intensity scouring of the electrode plate by the ion wind through the vertical arrangement of the needle tip and the electrode plate. This weakens the accumulation of viscous absorbent on the electrode plate, reduces the frequency of intermittent spray cleaning, avoids dilution of the absorbent during cleaning, and effectively improves the enrichment effect.

[0015] Preferably, the first absorbent zone high-efficiency washing section and the second absorbent zone high-efficiency washing section use desulfurization liquid with low pH (pH 3~4.5) supplemented by desulfurization slurry tank.

[0016] Preferably, the flue gas desulfurization and cooling section adopts a multi-stage spray design, using unidirectional or bidirectional hollow cone nozzles. The absorbent is replenished from a self-recovered absorbent enrichment tank. The absorbent is enriched by passing through a first absorbent zone high-efficiency washing section, a second absorbent zone high-efficiency washing section, and an ion wind flushing charged collection section. Cooling and desulfurization can be performed by reusing the absorbent, avoiding absorbent replenishment and achieving low-loss synergistic removal of pollutants and CO2. Most of the water in the enriched liquid of the flue gas desulfurization and cooling section evaporates from the high-temperature flue gas, avoiding absorbent dilution. After saturation, the absorbent in the flue gas desulfurization and cooling section can be widely used in the production of value-added products such as ammonium sulfate and thioamine after filtration and ion exchange.

[0017] The present invention also provides a method for reusing desulfurization and decarbonization absorbent, which uses the above-mentioned system and includes the following steps:

[0018] (1) After the flue gas is treated by the flue gas desulfurization and cooling section, it enters the zoned absorption tower. In the zoned absorption tower, the desulfurization zone, the first decarbonization zone, and the second decarbonization zone generate high-concentration gaseous substances (concentration 10) during the absorption of SO2 and CO2. 2 ~10 4 ppm) and aerosol (concentration 10) 2 ~10 3 mg / m 3If the absorbent escapes, it will be pretreated by the demister at the top of the tower and then enter the integrated device for high-efficiency capture and reuse of absorbents and pollutants. The zoned absorption towers are separated by gas lifting caps, and the absorbents in each zone are strictly distinguished.

[0019] (2) The escaped gaseous absorbent is absorbed by the desulfurization liquid with low pH (pH 3~4.5) in the first absorbent zone high-efficiency washing section and the second absorbent zone high-efficiency washing section. Some of the aerosol absorbent is removed under the action of inertial interception and acid absorption. Then the flue gas enters the ion wind flushing charged collection section. The aerosol absorbent is captured under the action of electric field force. Some of the unwashed gaseous absorbent is polarized under the action of charged ions and then enhanced to change into liquid phase. The purified flue gas is discharged into the atmosphere. The collected absorbent is enriched in the recovery absorbent enrichment tank.

[0020] (3) After the absorbent concentration in the absorbent enrichment tank reaches the standard, it is transported to the flue gas desulfurization and cooling section to regulate the temperature and pre-desulfurize and remove dust from the flue gas at the desulfurization and decarbonization inlet through circulating spraying, so as to realize the effective recovery and utilization of absorbent; most of the water in the enrichment liquid is evaporated by the high temperature flue gas; the salt-containing droplets and particles that condense and crystallize with the flue gas are captured by the inertial interception of spraying and demisting; after the absorbent in the flue gas desulfurization and cooling section is saturated, it is filtered and ion exchanged and then used for the production of value-added products; the absorbent in the desulfurization absorbent tank, the first decarbonization absorbent tank, and the second decarbonization absorbent tank is supplemented by amine or ammonia tank.

[0021] The first and second absorbent partition high-efficiency washing sections use saturated low-pH (pH 3~4.5) desulfurization liquid replenished by the desulfurization slurry tank to improve the absorption efficiency of the escape absorbent. Compared with water washing, the first and second absorbent partition high-efficiency washing sections can use a lower liquid flow rate, achieving low water consumption of the flue gas treatment system, which is conducive to the enrichment of absorbent and improves reuse performance.

[0022] In addition, the present invention also provides a method for regulating the above-mentioned desulfurization and decarbonization absorbent reuse system, comprising the following steps:

[0023] Step S1: Establish a database of flue gas parameters, absorbent and recovery liquid parameters, and corona discharge parameters based on real-time and historical data. Specific parameters include flue gas flow rate. G pH values ​​of the desulfurization absorbent tank, decarbonization absorbent tank, and recovered absorbent enrichment tank. pH i ,temperature T i Circulation volume L i Absorbent tank level H i The voltage of the ion wind scouring the charged collection section U 12 CurrentI 12 ; Replenish fluid volume L 3-9 , L 9-2 , L 9-7 , L 13-3 , L 13-14 ;

[0024] Step S2: Determine the partial pressure of ammonia or amine in the absorbent based on real-time and historical data. p NH3-amine N2 concentration in absorbent flue gas n N2 N2 voltage divider p N2 SO2 concentration n SO2 SO2 partial pressure p SO2 CO2 concentration n CO2 CO2 partial pressure p CO2 water vapor concentration n H2O partial pressure of water vapor p H2O Based on Dalton's law of partial pressure, the concentration of amine or ammonia emitted during the absorption process is predicted. C NH3-amine Obtain the total amount of substance at the outlet of the absorption tower. n absorber This leads to the creation of a database of absorbent escape emission concentrations during operation;

[0025]

[0026]

[0027]

[0028] Step S3: Based on the database established in Steps S1 and S2, establish an optimization model for the efficient reuse and absorption of pollutants and CO2 under different operating conditions, to realize the different functions of various parts (each part of the desulfurization and decarbonization absorbent reuse system) such as the integrated device for efficient absorbent capture, reuse and absorption of pollutants, the pollutant and CO2 zoned absorption tower, and the flue gas desulfurization and cooling section. This model regulates the system's water balance and material (absorbent) balance, supporting the coordinated and optimized operation of each part of the desulfurization and decarbonization absorbent reuse system. The following constraints are set for the adjustment range of each operating parameter:

[0029]

[0030]

[0031]

[0032]

[0033]

[0034] in, , The CO2 removal efficiency and the target efficiency are listed in order. , The SO2 removal efficiency and the target efficiency are listed in order. , In order, the removal efficiency of escaped ammonia or amine and the target efficiency are respectively; , In order, the aerosol removal efficiency and the target efficiency are: p in The total pressure of the flue gas at the system inlet;

[0035] Step S4: Establish a model for key control parameters. The specific model is as follows:

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042] Step S5: Combining the consumption of absorbent, the amount of absorbent escape, and the material and energy consumption costs of each functional area under real-time operating conditions, optimize the material and energy consumption costs based on the particle swarm optimization algorithm, thereby determining the optimal parameter combination, collecting the system output emission values, and repeating steps S3 to S4. Through advanced control methods including predictive control and fuzzy control, until the optimal energy and material consumption values ​​are reached, achieving steady-state operation with optimal comprehensive energy efficiency and cost.

[0043] The beneficial effects of this invention are as follows:

[0044] 1. Compared to carbon dioxide, sulfur oxides react more readily with the absorbent, thereby promoting the mass transfer of amine / ammonia-based absorbent components from the gas phase to the aerosol phase. The presence of SO2 significantly increases the aerosol number concentration, by 48.43% compared to the CO2-only condition, with aerosol particle size concentrated around 1 μm, indicating significant aerosol aggregation and growth. This phenomenon is mainly due to SO2's stronger binding capacity for absorbent components (ammonia / amine), water, and other molecules, resulting in a significantly larger initial aerosol cluster size than in the CO2-only case. On the other hand, the addition of SO2 may lead to the oxidative degradation of amines, resulting in the formation of more degradation products in the aerosol, reducing the amine concentration, and consequently causing more amine to transfer into the aerosol. Meanwhile, SO2 hinders the performance and chemical stability of CO2 absorbents, leading to a decrease in CO2 capture efficiency. With increasing SO2 concentration, the CO2 capture efficiency drops to 28.5%. Similar to the effect of SO2, the more acidic SO3 limits the reaction between CO2 and the absorbent, and a higher absorbent loss rate reduces the amount of absorbent available for CO2 capture, resulting in a decrease in CO2 capture efficiency. To address these issues, this invention proposes a multi-component, segmented recovery gas-liquid separation method based on washing-charging-condensation. By decoupling and controlling parameters such as absorbent temperature and liquid-to-gas ratio in the absorption process, aerosol emission reduction at the source is achieved. By increasing the washing temperature and flow rate in the high-efficiency washing section, the aerosol removal efficiency can reach up to 66.2%. By controlling the polarity, discharge parameters, and operating voltage of the ion wind-flushing charged capture section, the aerosol removal efficiency can reach over 98%, while the CO2 removal efficiency can reach over 90%.

[0045] 2. The system adopts a highly integrated design, including a flue gas desulfurization and cooling section, a recovered absorbent enrichment tank, a zoned high-efficiency washing section for absorbent, and an ion wind flushing and charging collection section. This design saves more than 50% of the system's space and is beneficial for the retrofitting of existing flue gas treatment systems. The recovered absorbent is used for flue gas desulfurization and cooling at the system inlet, solving the problem of reusing low-concentration absorbent and reducing enrichment and wastewater treatment processes. The entire system ensures that desulfurization meets ultra-low emission requirements and has superior economic efficiency and practicality.

[0046] 3. The absorbent recovery process (including the absorbent partition high-efficiency washing section and the ion wind flushing charged collection section) achieves high-efficiency absorption of escaped absorbent by reusing saturated desulfurization absorbent through low pH (pH 3~4.5) solvent. The absorbent recovery and collection efficiency can reach more than 95%, maximizing the utilization of absorbent in the system. The system absorbent loss rate is reduced by more than 90% compared with conventional desulfurization and decarbonization systems, and no additional water or other material consumption is required. Compared with conventional desulfurization and decarbonization integrated systems, the system operating cost can be reduced.

[0047] 4. A flexible control method for a highly efficient system for reusing and absorbing pollutants in desulfurization and decarbonization was developed. Based on training, numerical prediction, and iterative optimization using real-time and historical data from a particle swarm optimization algorithm, this method ensures desulfurization efficiency, decarbonization efficiency, gaseous amine / ammonia removal efficiency, and aerosol removal efficiency. Through precise control of parameters such as temperature at different levels, circulating liquid volume, solvent pH, and liquid level, the system optimizes the coordinated configuration of various components, achieving a reduction of absorbent loss rate of over 95% compared to conventional desulfurization and decarbonization systems. The removal efficiency of gaseous ammonia or amines and aerosols exceeds 99%. Based on optimized control of ammonia or amine supplementation, the decarbonization efficiency is increased to over 90%, reaching a maximum of 99%. The system's water balance and absorbent balance are controlled, supporting the coordinated and optimized operation of the absorbent reuse system and the desulfurization and decarbonization system. Compared to conventional integrated desulfurization and decarbonization systems, this method can reduce system operating costs by over 25%. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the desulfurization and decarbonization absorbent reuse system of the present invention;

[0049] Figure 2 This is a schematic diagram of the novel discharge structure of the ion wind scouring charged collection section of the present invention;

[0050] Figure 3 This is a flowchart of the control method for the desulfurization and decarbonization absorbent reuse system of the present invention;

[0051] Illustration:

[0052] Integrated device for high-efficiency capture and reuse of absorbent and absorption of pollutants: 1. Flue gas desulfurization and cooling section; 2. Desulfurization absorbent pool; 3. Desulfurization zone; 4. First decarbonization zone; 5. Second decarbonization zone; 6. Tower top demister; 7. Zoned absorption tower; 8. Recovered absorbent enrichment pool; 9. First absorbent zoned high-efficiency washing section; 10. Second absorbent zoned high-efficiency washing section; 11. Ion wind flushing charged capture section; 12. Ammonia replenishment pool; 13. First decarbonization absorbent pool; 14. Second decarbonization absorbent pool; 15. Detailed Implementation

[0053] The technical solution of the present invention will be further described in detail below through embodiments. These embodiments are for illustrative purposes only and are not intended to limit the present invention. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0054] Unless otherwise specified, the experimental methods described in the embodiments are conventional methods; the percentages mentioned are all mass percentages unless otherwise specified; and the reagents and materials mentioned are all commercially available unless otherwise specified.

[0055] Example 1

[0056] Reference Figures 1-3 A desulfurization and decarbonization absorbent reuse system (a high-efficiency desulfurization and decarbonization absorbent reuse and pollutant absorption system) mainly includes an integrated device 1 for high-efficiency capture, reuse, and pollutant absorption of absorbent and a matching zoned absorption tower (pollutant and CO2 zoned absorption tower) 8. Flue gas containing SO2, PM, CO2, and other components enters the pollutant and CO2 zoned absorption tower 8, where desulfurization and decarbonization are integrated in the desulfurization zone 4, the first decarbonization zone 5, and the second decarbonization zone 6. The zoned absorption towers are separated by gas lift caps, and the absorbents in each zone are stored in different absorption tanks for strict differentiation. The absorbents in the desulfurization absorbent tank 3, the first decarbonization absorbent tank 14, and the second decarbonization absorbent tank 15 are replenished by amine or ammonia tank 13. During the absorption of SO2 and CO2, the absorbent volatilizes, condenses, and escapes, generating high-concentration gaseous and aerosol absorbents. After pretreatment by the tower top demister 7, these absorbents enter the integrated device 1 for high-efficiency capture, reuse, and pollutant absorption of absorbent.

[0057] The flue gas first enters the first absorbent zone high-efficiency scrubbing section 10 and the second absorbent zone high-efficiency scrubbing section 11. The scrubbing liquid in this section is supplemented by desulfurization liquid with low pH and low free ammonia or amine concentration saturated in the desulfurization slurry tank 3, which can improve the absorption efficiency of the escape absorbent. Alkaline gaseous absorbents such as gaseous amines / ammonia are dissolved in acidic desulfurization saturated liquid. The first absorbent zone high-efficiency scrubbing section 10 and the second absorbent zone high-efficiency scrubbing section 11 adopt a packing design, and some aerosol absorbents are removed under the action of inertial interception and acid absorption. Compared with water washing, a lower liquid flow rate can be used, realizing low water consumption of the flue gas treatment system, which is conducive to the enrichment of absorbent and improves reuse performance.

[0058] The flue gas, carrying most of the aerosols and a small amount of unabsorbed gaseous absorbent, enters the ion wind scouring charged collection section 12. The aerosol absorbent becomes charged after corona discharge and is collected by the honeycomb collection plate under the influence of the electric field. Some of the unwashed gaseous absorbent is polarized under the influence of high-concentration charged ions, thus undergoing enhanced phase transformation into a liquid phase, and is finally collected on the collection plate. The structure of the ion wind scouring charged collection section 12 is as follows: Figure 2 The ion wind scouring charged collection section 12 adopts a honeycomb tube array arrangement. A novel snowflake-type ion wind scouring enhanced electrode is placed at the geometric center of the collection tube in each tube. Through the coupling and regulation of ion wind and corona discharge, the intensity of honeycomb charged collection discharge is improved, significantly improving the aerosol collection efficiency. The purified low-pollution flue gas can be discharged into the atmosphere. In addition, through the vertical arrangement of the needle tip and the electrode plate, the high-velocity airflow brought by the ion wind achieves high-intensity scouring of the electrode plate, weakens the accumulation of viscous absorbent on the electrode plate, reduces the cleaning frequency of intermittent spraying, avoids the dilution of absorbent by cleaning, and effectively improves the enrichment effect. The collected absorbent is enriched in the recovery absorbent enrichment tank 9.

[0059] As the length of the electrode tip increases, the discharge intensity increases, but the ion diffusion range generated by the tip discharge narrows and the current density on both sides of the tip decreases. Therefore, the preferred length of the electrode tip is 10~15mm.

[0060] As the spacing between electrode needle rows increases, the discharge intensity increases, and the breakdown voltage does not decrease significantly with the increase in the total number of needles. However, the current provided by each needle gradually decreases, the corresponding peak current density decreases to the maximum, and the tip utilization rate decreases. Therefore, a needle spacing of 20~50mm is preferred.

[0061] Through real-time monitoring of pH, liquid level, etc., after the absorbent concentration in the absorbent enrichment tank 9 reaches the standard, the enriched liquid is transported to the flue gas desulfurization and cooling section 2. Through a multi-stage spray design, the flue gas at the desulfurization and decarbonization inlet is circulated and sprayed for temperature control and pre-desulfurization and dust removal. The absorbent is reused for cooling and desulfurization, avoiding the need for absorbent replenishment. This achieves low-loss synergistic removal of pollutants and CO2, and realizes effective recycling of the absorbent. The use of unidirectional or bidirectional hollow cone nozzles for spraying ensures that most of the water in the enriched liquid evaporates from the high-temperature flue gas. Salt droplets and particles that condense and crystallize with the flue gas are captured by the inertial interception of the spraying and demisting action. The evaporation of most of the water in the enriched liquid from the high-temperature flue gas avoids the dilution of the absorbent and solves the water balance problem of the desulfurization and decarbonization system. After the absorbent is saturated, it can be widely used in the production of value-added products such as ammonium sulfate and thioamine after filtration and ion exchange.

[0062] Reference Figure 3 The system for efficient reuse and absorption of pollutants by desulfurization and decarbonization absorbents is configured with targeted and flexible control methods. Based on particle swarm optimization, it achieves precise prediction and flexible control of the integrated device 1 for efficient capture and reuse of absorbents and the zoned absorption tower 8 for pollutants and CO2. The specific steps include the following:

[0063] Step S1: Establish a database of flue gas parameters, absorbent and recovery liquid parameters, and corona discharge parameters based on real-time and historical data. Specific parameters include flue gas flow rate. G pH values ​​of each module (desulfurization absorbent tank, decarbonization absorbent tank, recovered absorbent enrichment tank, etc.) pH i ,temperature T i Circulation volume L i Absorbent tank level H i The voltage of the ion wind scouring the charged collection section U 12 Current I 12 ; Replenish fluid volume L 3-9, L 9-2 , L 9-7 , L 13-3 , L 13-14 ;

[0064] Step S2: Determine the partial pressure of ammonia or amine in the absorbent based on real-time and historical data. p NH3-amine N2 concentration in absorbent flue gas n N2 N2 voltage divider p N2 SO2 concentration n SO2 SO2 partial pressure p SO2 CO2 concentration n CO2 CO2 partial pressure p CO2 water vapor concentration n H2O partial pressure of water vapor p H2O Based on Dalton's law of partial pressure, the concentration of amine or ammonia emitted during the absorption process is predicted. C NH3-amine Obtain the total amount of substance at the outlet of the absorption tower. n absorber This leads to the creation of a database of absorbent escape emission concentrations during operation;

[0065]

[0066]

[0067]

[0068] Step S3: Based on the established database, establish an optimization model for the synergistic capture and absorption of pollutants and CO2 under different operating conditions, and for the efficient reuse and absorption of absorbents. This model aims to realize the different functions of the integrated device for efficient capture, reuse, and absorption of pollutants using absorbents, the zoned absorption towers for pollutants and CO2, and the flue gas desulfurization and cooling section. It also aims to regulate the system's water balance and absorbent balance, supporting the synergistic optimization operation of the absorbent reuse system and the desulfurization and decarbonization system. The following constraints are set for the adjustment range of each operating parameter:

[0069]

[0070]

[0071]

[0072]

[0073]

[0074] in, , The CO2 removal efficiency and the target efficiency are listed in order. , The SO2 removal efficiency and the target efficiency are listed in order. , In order, the removal efficiency of escaped ammonia or amine and the target efficiency are respectively; , In order, the aerosol removal efficiency and the target efficiency are: p in The total pressure of the flue gas at the system inlet;

[0075] Step S4: Establish a model for key control parameters. The specific model is as follows:

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082] Step S5: Combining the consumption of absorbent, the amount of absorbent escape, and the material and energy consumption costs of each functional area under real-time operating conditions, optimize the material and energy consumption costs based on the particle swarm optimization algorithm, thereby determining the optimal parameter combination, collecting the system output emission values, and repeating steps S3 to S4. Through advanced control methods including predictive control and fuzzy control, until the optimal energy and material consumption values ​​are reached, achieving steady-state operation with optimal comprehensive energy efficiency and cost.

[0083] The integrated desulfurization and decarbonization design is achieved through the desulfurization zone 4, the first decarbonization zone 5, and the second decarbonization zone 6 within the absorption tower. This enables the synergistic absorption and removal of pollutants and CO2 within the same unit. Combined with the reuse of absorbent in the flue gas desulfurization and cooling section 2, the SO2 removal efficiency can reach over 95%, and the CO2 capture efficiency can exceed 80%. The absorbent recovery process (including the high-efficiency washing section of the absorbent zone and the ion wind flushing charged capture section) can achieve an absorbent capture efficiency of over 95%, a gaseous ammonia or amine removal efficiency of over 95%, and a reduction in system absorbent loss rate by over 90%.

[0084] Through flexible adjustment, the system utilizes a combination of real-time and historical data training, numerical prediction, and iterative optimization based on particle swarm optimization to optimize the collaborative configuration between modules. This results in a reduction of absorbent loss rate by over 95% compared to conventional desulfurization and decarbonization systems, SO2 removal efficiency exceeding 99%, removal efficiency of gaseous ammonia or amines and aerosols exceeding 99%, and decarbonization efficiency exceeding 90%. By regulating the system's water balance and absorbent balance, the system supports the coordinated and optimized operation of the absorbent reuse system and the desulfurization and decarbonization system, achieving steady-state operation with optimal overall energy efficiency and cost.

[0085] Example 2

[0086] A first absorbent-zoned high-efficiency scrubbing section and a second absorbent-zoned high-efficiency scrubbing section are installed before the ion wind scouring charged collection section to further improve the aerosol removal efficiency. After flue gas temperature adjustment in the water washing section, the flue gas temperature decreases by approximately 2°C, the number of aerosols in the 0.009-0.017 μm range decreases, while the number of aerosols in the 0.026-0.042 μm range increases, and the aerosol particle size increases by 6%-8%. The aerosol removal efficiency reaches 98.40%-98.81%. For the ion wind scouring charged collection section, to obtain good aerosol removal performance, the applied voltage is preferably 35 kV, with an aerosol removal efficiency greater than 98% and an outlet concentration lower than 1 mg / m³. 3 .

[0087] This invention proposes an integrated device for efficient collection and reuse of pollutants by absorbent, and a flexible control method adapted to the system, while ensuring efficient desulfurization and decarbonization. Addressing practical issues such as high absorbent loss, severe secondary pollution, and difficulties in achieving water and material balance in desulfurization and decarbonization systems, this system employs a highly integrated design comprising a flue gas desulfurization and cooling section, a recovered absorbent enrichment tank, a zoned high-efficiency washing section for the absorbent, and an ion wind flushing and charged collection section. This design saves over 50% of system space and facilitates the retrofitting of existing flue gas treatment systems. The recovered absorbent is used for desulfurization and cooling of the system's inlet flue gas, solving the problem of reusing low-concentration absorbents, reducing enrichment and wastewater treatment processes, and avoiding dilution of the absorbent components during washing. The entire system ensures that desulfurization meets ultra-low emission requirements, reducing absorbent loss by over 95%, achieving over 99% removal efficiency for gaseous ammonia or amines and aerosols, and increasing decarbonization efficiency to over 95%, even reaching 99%. It regulates system water and absorbent balance, supporting the coordinated and optimized operation of the absorbent reuse system and the desulfurization and decarbonization system, reducing system operating costs by over 25%. This system boasts superior economic efficiency and practicality, facilitating the promotion of clean and long-term pollution reduction technologies. This also lays the foundation for further optimizing the layout of the flue gas purification system, shortening the flue gas treatment process, and carrying out the synergistic removal of CO2 and other pollutants.

[0088] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A system for reusing desulfurization and decarbonization absorbent, characterized in that: The system includes interconnected zoned absorption towers and an integrated device for efficient collection, reuse, and absorption of pollutants using absorbent. Each zoned absorption tower comprises, from bottom to top, a desulfurization zone, a first decarbonization zone, a second decarbonization zone, and a top demister. The desulfurization zone is connected to a desulfurization absorbent pool, the first decarbonization zone is connected to a first decarbonization absorbent pool, and the second decarbonization zone is connected to a second decarbonization absorbent pool. The desulfurization absorbent pool, the first decarbonization absorbent pool, and the second decarbonization absorbent pool are respectively connected to an amine replenishment pool or an ammonia pool. The integrated device for efficient collection and reuse of absorbent pollutants includes, from bottom to top, a flue gas desulfurization and cooling section, a recovered absorbent enrichment tank, a first zoned efficient scrubbing section for absorbent, a second zoned efficient scrubbing section for absorbent, and an ion wind flushing charged collection section. The recovered absorbent enrichment tank is connected to the first zoned efficient scrubbing section for absorbent, the second zoned efficient scrubbing section for absorbent, the ion wind flushing charged collection section for absorbent, the flue gas desulfurization and cooling section for flue gas, and the top demisting device. The desulfurization absorbent tank is connected to the recovered absorbent enrichment tank. The ion wind scouring charged collection section is arranged in a honeycomb tube array, and a snowflake-type ion wind scouring enhanced electrode is used in a single tube. The snowflake-type ion wind scouring enhanced electrode is placed at the geometric center of the collection tube, wherein the electrode tip is perpendicular to the tube wall of the collection tube. The control method for the desulfurization and decarbonization absorbent reuse system includes the following steps: Step S1: Establish a database of flue gas parameters, absorbent and recovery liquid parameters, and corona discharge parameters based on real-time and historical data. Specific parameters include flue gas flow rate. G pH values ​​of the desulfurization absorbent tank, decarbonization absorbent tank, and recovered absorbent enrichment tank. pH i ,temperature T i Circulation volume L i Absorbent tank level H i The voltage of the ion wind scouring the charged collection section U 12 Current I 12 ; Replenish fluid volume L 3-9 , L 9-2 , L 9-7 , L 13-3 , L 13-14 ; Step S2: Determine the partial pressure of ammonia or amine in the absorbent based on real-time and historical data. p NH3-amine N2 concentration in absorbent flue gas n N2 N2 voltage divider p N2 SO2 concentration n SO2 SO2 partial pressure p SO2 CO2 concentration n CO2 CO2 partial pressure p CO2 water vapor concentration n H2O partial pressure of water vapor p H2O Based on Dalton's law of partial pressure, the concentration of amine or ammonia emitted during the absorption process is predicted. C NH3-amine Obtain the total amount of substance at the outlet of the absorption tower. n absorber This leads to the creation of a database of absorbent escape emission concentrations during operation; ； ； ； Step S3: Based on the database established in Steps S1 and S2, establish an optimization model for the synergistic capture and absorption of pollutants and CO2 under different operating conditions, and for the efficient reuse of absorbents. This model aims to realize the different functions of various components, including the integrated device for efficient capture, reuse, and absorption of absorbents, the zoned absorption towers for pollutants and CO2, and the flue gas desulfurization and cooling section. It also aims to regulate the system's water and material balance, supporting the synergistic optimization of various components within the desulfurization and decarbonization absorbent reuse system. The following constraints are set for the adjustment range of each operating parameter: ； ； ； ； ； in, , The CO2 removal efficiency and the target efficiency are listed in order. , The SO2 removal efficiency and the target efficiency are listed in order. , In order, the removal efficiency of escaped ammonia or amine and the target efficiency are respectively; , In order, the aerosol removal efficiency and the target efficiency are: p in The total pressure of the flue gas at the system inlet; Step S4: Establish a model for key control parameters. The specific model is as follows: ； ； ； ； ； ； Step S5: Combining parameters including absorbent consumption, absorbent escape, and material and energy consumption costs of each functional area under real-time operating conditions, optimize material and energy consumption costs based on particle swarm optimization algorithm to determine the optimal parameter combination, collect system output emission values, and repeat steps S3 to S4. Through advanced control methods including predictive control and fuzzy control, until the optimal energy and material consumption values ​​are reached, achieving steady-state operation with optimal comprehensive energy efficiency and cost.

2. The desulfurization and decarbonization absorbent reuse system according to claim 1, characterized in that: The electrode tip length is 10~15mm, and the electrode spacing is 20~50mm.

3. The desulfurization and decarbonization absorbent reuse system according to claim 1, characterized in that: The first absorbent zone high-efficiency washing section and the second absorbent zone high-efficiency washing section use desulfurization liquid supplemented by desulfurization slurry tank.

4. The desulfurization and decarbonization absorbent reuse system according to claim 1, characterized in that: The flue gas desulfurization and cooling section adopts a multi-stage spray design, using unidirectional or bidirectional hollow cone nozzles for spraying. The absorbent is replenished by a self-recovering absorbent enrichment tank. The absorbent is enriched by passing through the first absorbent partition high-efficiency washing section, the second absorbent partition high-efficiency washing section, and the ion wind flushing charged collection section.

5. A method for reusing a desulfurization and decarbonization absorbent, characterized in that: The system according to any one of claims 1-4 comprises the following steps: (1) After the flue gas is treated by the flue gas desulfurization and cooling section, it enters the zoned absorption tower. In the zoned absorption tower, the desulfurization zone, the first decarbonization zone, and the second decarbonization zone generate SO2 and CO2 with a concentration of 10 during the absorption process. 2 ~10 4 High concentrations of gaseous matter at ppm and concentrations of 10 2 ~10 3 mg / m 3 The aerosol absorbent that escapes is pretreated by the top demister and then enters the integrated device for efficient capture and reuse of absorbent pollutants. The zoned absorption tower is separated by a gas-lifting cap, and the absorbents in each zone are strictly distinguished. (2) The escaped gaseous absorbent is absorbed by the desulfurization liquid with pH 3~4.5 in the first absorbent zone high-efficiency washing section and the second absorbent zone high-efficiency washing section. Some of the aerosol absorbent is removed under the action of inertial interception and acid absorption. Then the flue gas enters the ion wind flushing charged collection section. The aerosol absorbent is captured under the action of electric field force. Some of the unwashed gaseous absorbent is polarized under the action of charged ions and then enhanced to change into liquid phase. The purified flue gas is discharged into the atmosphere. The collected absorbent is enriched in a recycled absorbent enrichment tank; (3) After the absorbent in the absorbent enrichment tank reaches pH > 8.5, it is transported to the flue gas desulfurization and cooling section to regulate the temperature and pre-desulfurize and remove dust from the flue gas at the desulfurization and decarbonization inlet through circulating spraying, so as to realize the effective recovery and utilization of absorbent; most of the water in the enrichment liquid is evaporated by the high temperature flue gas; the salt droplets and particles that condense and crystallize with the flue gas are captured by the inertial interception of spraying and demisting; after the absorbent in the flue gas desulfurization and cooling section is saturated, it is filtered and ion exchanged and then used for the production of value-added products; the absorbent in the desulfurization absorbent tank, the first decarbonization absorbent tank, and the second decarbonization absorbent tank is replenished by amine or ammonia tank.

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