Supergravity carbon dioxide trapping system and control method thereof

Abstract

The invention belongs to the technical field of carbon capture systems, and provides a supergravity carbon dioxide capture system and a control method thereof, by introducing a supergravity desorption device and a heat recoverer, the regeneration energy consumption is effectively reduced, and the energy utilization efficiency is improved; cold barren liquor produced by the barren-rich liquor heat exchanger is conveyed into the absorption tower 1 again through a second barren liquor pump to be recycled, so that the emission of amine is effectively reduced, and the environmental pollution is reduced; through multi-stage treatment of the regeneration gas heat recovery unit, the humidifying section and the washing section, small particles and aerosol in the flue gas are effectively removed, and the CO2 trapping efficiency is improved; meanwhile, flow control strategies of a washing pump, a pregnant solution pump, a first barren solution pump, a second barren solution pump and the like are adjusted according to the pregnant solution temperature, the regenerated gas temperature, the absorption tower load and flue gas components, and the reasonability of heat utilization and temperature control is improved.

Description

Technical Field

[0001] The present invention belongs to the field of carbon capture systems, and in particular relates to a high-gravity carbon dioxide capture system and a control method thereof. Background Art

[0002] Among existing carbon dioxide capture technologies, amine solutions are widely used due to their efficient CO2 absorption capacity. However, during the treatment process of traditional carbon dioxide capture systems, amine emissions are often high, which not only causes waste of resources but also may have negative impacts on the environment.

[0003] Existing regeneration systems consume high energy and are prone to producing large amounts of tail gas scrubbing water containing amines during the process. If improperly handled, these amines can volatilize into the atmosphere, causing pollution. Furthermore, existing technologies are inadequate in their treatment of small particles and aerosols in flue gas. These tiny particles and aerosols are difficult to effectively remove and may be emitted into the atmosphere along with the flue gas, posing a potential threat to the environment. In particular, existing technologies fail to consider control strategies for varying trends in rich liquid temperature, regeneration gas temperature, absorber load regulation, flue gas composition, and flow rate, leading to irrational heat utilization and temperature control in some processes. Summary of the Invention

[0004] In order to solve the above problems, the present invention proposes a high-gravity carbon dioxide capture system and a control method thereof. By introducing a high-gravity desorption device and a heat recovery device, the regeneration energy consumption is effectively reduced and the energy utilization efficiency is improved; the cold lean liquid output by the lean-rich liquid heat exchanger is re-transported to the inside of the absorption tower for recycling through the second lean liquid pump, thereby effectively reducing amine emissions and reducing environmental pollution; through multi-stage treatment of the regeneration gas heat recovery unit, humidification section and water washing section, tiny particles and aerosols in the flue gas are effectively removed, and the CO2 capture efficiency is improved; at the same time, the flow control strategy of the water washing pump, the rich liquid pump, the first lean liquid pump and the second lean liquid pump is adjusted according to the rich liquid temperature, the regeneration gas temperature, the absorption tower load and the flue gas composition, thereby improving the rationality of heat utilization and temperature control.

[0005] In order to achieve the above objectives, in a first aspect, the present invention provides a high-gravity carbon dioxide capture system, which adopts the following technical solutions: A high-gravity carbon dioxide capture system comprises an absorption tower, and a regeneration gas heat recovery unit, a humidification section, and a water washing section arranged on the absorption tower; The regeneration gas heat recovery unit is arranged at the bottom of the absorption tower, and the regeneration gas heat recovery unit includes a rich liquid pump connected to the absorption tower through a pipeline, a heat recovery device and a lean-rich liquid heat exchanger respectively connected to the rich liquid pump through pipelines, a first lean liquid pump arranged between the supergravity desorption device and the lean-rich liquid heat exchanger through a pipeline, and a second lean liquid pump arranged between the lean-rich liquid heat exchanger and the absorption tower through a pipeline; the supergravity desorption device is connected to the heat recovery device through a pipeline; The humidification section and the water washing section are arranged at the top of the absorption tower, and are used to humidify the flue gas and cool the flue gas washing water, respectively; an aerosol growth section is provided at the end of the water washing section; and a reboiler is connected to the bottom of the supergravity desorption device; The water washing section is provided with a water washing pump, and the water washing pump, the rich liquid pump, the first lean liquid pump and the second lean liquid pump are connected to a controller, and the controller adjusts the flow of each pump according to the rich liquid temperature, the regeneration gas temperature, the absorption tower load and the flue gas composition.

[0006] Furthermore, the heat recovery device is arranged on the top of the supergravity desorption device, and the lean and rich liquid heat exchanger is arranged between the absorption tower and the supergravity desorption device.

[0007] Furthermore, a flue gas inlet is provided on the surface of the absorption tower, and the flue gas inlet is connected to a fan.

[0008] Furthermore, the lean liquid heat exchanger is provided with a first lean liquid inlet connected to the liquid outlet of the first lean liquid pump, and a second lean liquid outlet connected to the liquid inlet of the second lean liquid pump; the absorption tower is provided with a lean liquid inlet connected to the liquid outlet of the second lean liquid pump.

[0009] Furthermore, the water washing section includes a storage tank connected to the absorption tower and the aerosol growth section through a pipeline, and a water washing cooler and a water washing pump arranged between the storage tank and the absorption tower.

[0010] In order to achieve the above objectives, in a second aspect, the present invention further provides a method for controlling a high-gravity carbon dioxide capture system, which adopts the following technical solution: A method for controlling a high-gravity carbon dioxide capture system uses the high-gravity carbon dioxide capture system as described in the first aspect, including: a control strategy for adjusting a water wash pump, the rich liquid pump, a first lean liquid pump, and a second lean liquid pump based on the rich liquid temperature, the regeneration gas temperature, the absorption tower load, and the flue gas composition.

[0011] Furthermore, when the rich liquid temperature rises above a preset upper limit, the flow rate of the first lean liquid pump is increased to transport more hot lean liquid to the lean-rich liquid heat exchanger. At the same time, the flow rate of the second lean liquid pump is increased to transport more cooled lean liquid back to the absorption tower. When the rich liquid temperature is lower than a preset lower limit, the flow rate of the first lean liquid pump is reduced to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger. The flow rate of the second lean liquid pump is reduced to reduce the amount of cooled lean liquid refluxed to the absorption tower.

[0012] Furthermore, when the regeneration gas temperature is higher than the preset regeneration gas temperature upper limit, the flow rate of the first lean liquid pump is increased to transport more hot lean liquid to the lean-rich liquid heat exchanger, and the flow rate of the second lean liquid pump is increased to transport the cooled lean liquid back to the absorption tower; when the regeneration gas temperature is lower than the preset regeneration gas temperature lower limit, the flow rate of the first lean liquid pump is reduced to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger, and the flow rate of the second lean liquid pump is reduced to reduce the amount of cooled lean liquid refluxed to the absorption tower.

[0013] Furthermore, when the load of the absorption tower increases, the flow rate of the first lean liquid pump is increased, and the flow rate of the second lean liquid pump is increased to transport more cooled lean liquid back to the absorption tower, and the flow rate of the water washing pump is increased to ensure that sufficient cooling water enters the water washing section to maintain the temperature of the washing water; when the load of the absorption tower decreases, the flow rate of the first lean liquid pump is reduced, and the flow rate of the second lean liquid pump is reduced to reduce the amount of cooled lean liquid refluxed to the absorption tower, and the flow rate of the water washing pump is reduced to reduce the amount of cooling water entering the water washing section.

[0014] Furthermore, when the CO2 concentration in the flue gas increases and / or the flue gas flow rate increases, the flow rate of the first lean liquid pump is increased, and the flow rate of the second lean liquid pump is increased to transport more cooled lean liquid back to the absorption tower, and the flow rate of the water wash pump is increased to ensure that sufficient cooling water enters the water wash section; When the concentration of particulate matter or aerosol in the flue gas increases, increase the flow rate of the water washing pump to ensure that there is enough cooling water entering the water washing section, increase the regeneration gas heating power of the humidification section, and promote the growth and removal of particulate matter and aerosol.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention effectively reduces regeneration energy consumption and improves energy utilization efficiency by introducing a supergravity desorption device and a heat recovery device; the cold lean liquid output by the lean-rich liquid heat exchanger is re-transported to the inside of the absorption tower for recycling through the second lean liquid pump, thereby effectively reducing amine emissions and reducing environmental pollution; through multi-stage treatment of the regeneration gas heat recovery unit, humidification section and water washing section, tiny particles and aerosols in the flue gas are effectively removed, and the CO2 capture efficiency is improved; at the same time, the flow control strategy of the water washing pump, rich liquid pump, first lean liquid pump and second lean liquid pump is adjusted according to the rich liquid temperature, regeneration gas temperature, absorption tower load and flue gas composition, thereby improving the rationality of heat utilization and temperature control.

[0016] 2. In the control method of the present invention, by designing control strategies for rich liquid temperature, regeneration gas temperature, absorption tower load adjustment, flue gas composition and flow rate under different changing trends, the rationality of heat utilization and temperature control is improved, and the purposes of improving temperature stability in the absorption tower, maintaining system temperature balance, improving washing efficiency, and promoting the growth and removal of particulate matter and aerosols are achieved.

[0017] 3. The present invention effectively reduces amine emissions and environmental pollution by optimizing low-amine emission control measures. Through multi-stage treatment, it effectively removes tiny particles and aerosols in the flue gas and improves CO2 capture efficiency. The system has a simple structure, is easy to operate and maintain, and has high practicality and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting a part of the specification of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments and descriptions of this embodiment are used to explain this embodiment and do not constitute an improper limitation on this embodiment.

[0019] Figure 1 This is a schematic diagram of the system structure of Example 1 of the present invention; Among them, 1. Absorption tower; 2. Fan; 3. Supergravity desorption device; 4. Heat recovery device; 5. Lean and rich liquid heat exchanger; 6. Rich liquid pump; 7. First lean liquid pump; 8. Second lean liquid pump; 9. Humidification section; 10. Water washing section; 11. Storage tank; 12. Water washing cooler; 13. Water washing pump; 14. Aerosol growth section; 15. Reboiler. DETAILED DESCRIPTION

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0022] Example 1: like Figure 1 As shown, this embodiment provides a high-gravity carbon dioxide capture system designed to reduce amine emissions, improve CO2 capture efficiency, and minimize environmental impact by optimizing the regeneration system and low-amine emission control measures. The system includes an absorption tower 1, a fan 2, a high-gravity desorption device 3, a heat recovery device 4, a lean-rich liquid heat exchanger 5, a rich liquid pump 6, a first lean liquid pump 7, a second lean liquid pump 8, a humidification section 9, a water wash section 10, a storage tank 11, a water wash cooler 12, a water wash pump 13, an aerosol growth section 14, and a reboiler 15.

[0023] The fan 2 transports the flue gas to the interior of the absorption tower 1; specifically, in one embodiment, the surface of the absorption tower 1 is provided with a flue gas inlet connected to the air outlet end of the fan 2, and the top of the absorption tower 1 is provided with a decarbonized flue gas outlet.

[0024] The above design can facilitate the fan 2 to transport the flue gas into the absorption tower 1.

[0025] The supergravity desorption device 3, the heat recovery device 4, the lean-rich liquid heat exchanger 5, the rich liquid pump 6, the first lean liquid pump 7, and the second lean liquid pump 8 constitute a regeneration gas heat recovery unit. Optionally, the rich liquid inlet of the lean-rich liquid heat exchanger 5 and the rich liquid inlet of the heat recovery device 4 are respectively connected to the outlet of the rich liquid pump 6 via pipelines, and the inlet of the rich liquid pump 6 is connected to the absorption tower 1 via a pipeline. The lean-rich liquid heat exchanger 5 is also connected to the outlet of the first lean liquid pump 7 via a pipeline, and the inlet of the first lean liquid pump 7 is connected to the supergravity desorption device 3 via a pipeline. The first outlet of the lean-rich liquid heat exchanger 5 (the outlet connected to the rich liquid pump 6) is connected to the supergravity desorption device 3 via a pipeline, and the second outlet of the lean-rich liquid heat exchanger 5 (the outlet connected to the first lean liquid pump 7) is connected to the inlet of the second lean liquid pump 8 via a pipeline, and the outlet of the second lean liquid pump 8 is connected to the absorption tower 1 via a pipeline.

[0026] In one embodiment, the heat recovery device 4 is disposed on the top of the high-gravity desorption device 3 , and the lean-rich liquid heat exchanger 5 is disposed between the absorption tower 1 and the high-gravity desorption device 3 .

[0027] The above design can effectively recover the heat of the regeneration gas and reduce the regeneration energy consumption.

[0028] In one embodiment, the rich liquid pump 6 transports a portion of the rich liquid generated in the absorption tower 1 to the lean-rich liquid heat exchanger 5 for heat exchange, and transports another portion of the rich liquid to the heat recovery device 4 for heat exchange, and then transports it to the interior of the supergravity desorption device 3 for regeneration to obtain hot lean liquid and regenerated gas, and transports the hot lean liquid to the lean-rich liquid heat exchanger 5 through the first lean liquid pump 7 for heat exchange with the cold rich liquid, and finally enters the absorption tower 1 through the second lean liquid pump 8 for reuse, thereby improving the heat recovery utilization rate.

[0029] In one embodiment, the bottom outer surface of the absorption tower 1 is provided with a rich liquid outlet connected to the liquid inlet end of the rich liquid pump 6, and the surfaces of the lean and rich liquid heat exchanger 5 and the heat recovery device 4 are both provided with a rich liquid inlet connected to the liquid outlet end of the rich liquid pump 6.

[0030] The above design can facilitate the rich liquid pump 6 to transport the rich liquid in the absorption tower 1 to the inside of the lean and rich liquid heat exchanger 5 and the heat recovery device 4 respectively.

[0031] In one embodiment, a connecting pipe communicating with the supergravity desorption device 3 is provided at the bottom of the heat recovery device 4 , and a first lean liquid outlet communicating with the liquid inlet end of the first lean liquid pump 7 is provided at the bottom of the supergravity desorption device 3 .

[0032] The above design can facilitate the first lean liquid pump 7 to discharge the lean liquid produced by the supergravity desorption device 3 .

[0033] In one embodiment, the surface of the lean and rich liquid heat exchanger 5 is provided with a first lean liquid inlet connected to the liquid outlet end of the first lean liquid pump 7, and the outer surface of the lean and rich liquid heat exchanger 5 is provided with a second lean liquid outlet connected to the liquid inlet end of the second lean liquid pump 8, and the surface of the absorption tower 1 is provided with a second lean liquid inlet connected to the liquid outlet end of the second lean liquid pump 8.

[0034] The above design effectively recovers the heat of the regenerated gas and reduces the regeneration energy consumption. At the same time, the above design facilitates the first lean liquid pump 7 to transport the lean liquid produced by the supergravity desorption device 3 into the lean-rich liquid heat exchanger 5 for heat exchange, thereby realizing heat recovery and utilization. At the same time, the second lean liquid pump 8 transports the cold lean liquid produced by the lean-rich liquid heat exchanger 5 back to the inside of the absorption tower 1 for further recycling.

[0035] The humidification section 9 is disposed at the top of the absorption tower 1 and is used to humidify the flue gas. Specifically, in one embodiment, the humidification section 9 uses regeneration gas to heat the flue gas scrubbing water after the absorption tower 1, thereby humidifying the flue gas and promoting the rapid growth of small particles and aerosols. Optionally, the humidification section 9 includes at least one pipeline, one end of which extends into the absorption tower 1 and is equipped with a nozzle or other equipment, and the other end can be connected to a washing device or a liquid supply device through a pump and pipeline. This can be achieved using conventional technology and will not be described in detail here.

[0036] The water washing section 10 is used to cool the flue gas washing water and generate a large amount of condensed water to remove large particle droplets and volatile amines. The water washing section 10 includes a storage tank 11 connected to the absorption tower 1 and the aerosol growth section 14 through a pipeline, and a water washing cooler 12 and a water washing pump 13 arranged between the storage tank 11 and the absorption tower 1; The aerosol growth section 14 is provided at the end of the water washing section 10 and is used to remove aerosol.

[0037] In one embodiment, the aerosol growth section 14 uses a wire mesh demister to remove aerosol.

[0038] The reboiler 15 is disposed at the bottom of the supergravity desorption device 3 ; specifically, the reboiler 15 is used to provide secondary steam generated by vaporization of the lean liquid to the supergravity desorption device 3 .

[0039] At the same time, the first lean liquid pump 7, the second lean liquid pump 8 and the water wash pump 13 involved above can, during the operation of the entire supergravity carbon dioxide capture system, be controlled by a controller (such as an external PLC controller) to accurately and precisely control the flow rates of the first lean liquid pump 7, the second lean liquid pump 8 and the water wash pump 13 in real time, thereby maximizing energy utilization efficiency and capture efficiency.

[0040] Among them, by setting the heat recovery device 4, the lean-rich liquid heat exchanger 5, the rich liquid pump 6, the first lean liquid pump 7 and the second lean liquid pump 8, the rich liquid pump 6 transports a part of the rich liquid generated in the absorption tower 1 to the lean-rich liquid heat exchanger 5 for heat exchange, and transports another part of the rich liquid to the heat recovery device 4 for heat exchange, and then transports it to the interior of the supergravity desorption device 3 for regeneration to obtain hot lean liquid and regenerated gas, and transports the hot lean liquid to the lean-rich liquid heat exchanger 5 through the first lean liquid pump 7 for heat exchange with the cold rich liquid, and finally Then it enters the absorption tower 1 through the second lean liquid pump 8 for reuse. In this process, the heat of the regenerated gas is effectively recovered and the regeneration energy consumption is reduced. At the same time, through the above design, it is convenient for the first lean liquid pump 7 to transport the lean liquid produced by the supergravity desorption device 3 into the lean-rich liquid heat exchanger 5 for heat exchange, thereby realizing heat recovery and utilization. At the same time, the second lean liquid pump 8 transports the cold lean liquid produced by the lean-rich liquid heat exchanger 5 back to the absorption tower 1 for recycling and utilization, thereby effectively reducing amine emissions and reducing environmental pollution.

[0041] This embodiment effectively reduces regeneration energy consumption and improves energy efficiency by introducing a high-gravity desorption device and a heat recovery unit. Optimizing low-amine emission control measures effectively reduces amine emissions and minimizes environmental pollution. Multi-stage treatment effectively removes fine particles and aerosols from flue gas, improving CO2 capture efficiency. The system proposed in this embodiment boasts a simple structure, easy operation and maintenance, and high practicality and cost-effectiveness.

[0042] Example 2: This embodiment provides a method for controlling a high-gravity carbon dioxide capture system, using the high-gravity carbon dioxide capture system as described in the first aspect, including: a control strategy for adjusting the water wash pump, the rich liquid pump, the first lean liquid pump, and the second lean liquid pump according to the rich liquid temperature, the regeneration gas temperature, the absorption tower load, and the flue gas composition.

[0043] In one embodiment, the controller adjustment process includes: S1, adjust according to the rich liquid temperature: S1.1. The rich liquid temperature is too high, for example, exceeding a preset upper limit: A rise in the rich liquid temperature indicates that the system's heat recovery may be insufficient, and the lean liquid flow rate needs to be increased to remove more heat. Optionally, increase the flow rate of the first lean liquid pump 7 to deliver more hot lean liquid to the lean-rich liquid heat exchanger 5 to enhance heat exchange with the cold rich liquid. Simultaneously, appropriately increase the flow rate of the second lean liquid pump 8 to deliver more cooled lean liquid back to the absorption tower 1 to maintain a stable temperature within the absorption tower.

[0044] S1.2. The rich liquid temperature is too low, for example, below a preset lower limit: This indicates excessive heat recovery in the system, and the lean liquid flow rate needs to be reduced to prevent overcooling. Optionally, reduce the flow rate of the first lean liquid pump 7 to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger 5. Appropriately reduce the flow rate of the second lean liquid pump 8 to reduce the amount of cooled lean liquid refluxed to the absorption tower 1.

[0045] S2, adjust according to the regeneration gas temperature: S2.1. The regeneration gas temperature is too high, for example, above the preset upper regeneration gas temperature limit. This indicates that the reboiler 15 is providing too much heat, requiring increased lean liquid flow to absorb the excess heat. Optionally, increase the flow rate of the first lean liquid pump 7 to deliver more hot lean liquid to the lean-rich liquid heat exchanger 5 to absorb the heat from the regeneration gas. Appropriately increase the flow rate of the second lean liquid pump 8 to deliver the cooled lean liquid back to the absorption tower 1 to maintain system temperature balance.

[0046] S2.2. The regeneration gas temperature is too low, for example, below the preset lower limit. This indicates insufficient heat recovery and requires reducing the lean liquid flow rate to minimize heat absorption. Optionally, reduce the flow rate of the first lean liquid pump 7 to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger 5. Appropriately reduce the flow rate of the second lean liquid pump 8 to reduce the amount of cooled lean liquid refluxed to the absorption tower 1.

[0047] S3, according to the load adjustment of absorption tower 1: S3.1. Increased Load on Absorber 1: The increased load on Absorber 1 requires more lean liquid to absorb CO2 and more cooling water to maintain temperature. Optionally, increase the flow rate of the first lean liquid pump 7 to ensure sufficient hot lean liquid enters the lean-rich liquid heat exchanger 5. Increase the flow rate of the second lean liquid pump 8 to transport more cooled lean liquid back to Absorber 1. Increase the flow rate of the water wash pump 13 to ensure sufficient cooling water enters the water wash section 10 to maintain the wash water temperature.

[0048] S3.2. Reduce the load on absorber 1: As the load on absorber 1 decreases, the flow rates of lean liquid and cooling water need to be reduced to avoid waste. Optionally, reduce the flow rate of the first lean liquid pump 7 to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger 5. Reduce the flow rate of the second lean liquid pump 8 to reduce the amount of cooled lean liquid refluxed to absorber 1. Reduce the flow rate of the water wash pump 13 to reduce the amount of cooling water entering the water wash section 10.

[0049] S4. Adjust according to flue gas composition and flow rate: S4.1. Increased CO2 concentration in flue gas: Increased CO2 concentration requires more lean liquid to absorb the CO2 and more cooling water to maintain temperature. Optionally, increase the flow rate of the first lean liquid pump 7 to ensure sufficient hot lean liquid enters the lean-rich liquid heat exchanger 5. Increase the flow rate of the second lean liquid pump 8 to transport more cooled lean liquid back to the absorption tower 1. Increase the flow rate of the water wash pump 13 to ensure sufficient cooling water enters the water wash section 10.

[0050] S4.2. Increase Flue Gas Flow: Increased flue gas flow requires more lean liquid to absorb CO2 and more cooling water to maintain temperature. Optionally, increase the flow rate of the first lean liquid pump 7 to ensure sufficient hot lean liquid enters the lean-rich liquid heat exchanger 5. Increase the flow rate of the second lean liquid pump 8 to transport more cooled lean liquid back to the absorption tower 1. Increase the flow rate of the water wash pump 13 to ensure sufficient cooling water enters the water wash section 10.

[0051] S4.3. Increased concentration of particulate matter or aerosols in flue gas: Optionally, if the concentration of particulate matter or aerosols increases, it may be necessary to increase the cooling water flow rate in the water wash section 10 to improve scrubbing efficiency. Optionally, increase the flow rate of the water wash pump 13 to ensure sufficient cooling water enters the water wash section 10. Appropriately increase the regeneration gas heating power in the humidification section 9 to promote the growth and removal of particulate matter and aerosols.

[0052] In the above control strategy, data such as rich liquid temperature, regeneration gas temperature, load flue gas composition and flow rate can be achieved by setting temperature sensors, flue gas sensors and flow rate sensors at corresponding positions, which will not be described in detail here.

[0053] The above description is merely a preferred embodiment of this embodiment and is not intended to limit this embodiment. Those skilled in the art will readily appreciate that this embodiment may be modified and varied in various ways. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this embodiment shall be within the scope of protection of this embodiment.

Claims

1. A high gravity carbon dioxide capture system, characterized in that: It comprises an absorption tower (1), and a regeneration gas heat recovery unit, a humidification section (9), and a water washing section (10) arranged on the absorption tower (1); The regeneration gas heat recovery unit is arranged at the bottom of the absorption tower (1), and comprises a rich liquid pump (6) connected to the absorption tower (1) through a pipeline, a heat recovery device (4) and a lean-rich liquid heat exchanger (5) respectively connected to the rich liquid pump (6) through pipelines, a first lean liquid pump (7) arranged between the supergravity desorption device (3) and the lean-rich liquid heat exchanger (5) through a pipeline, and a second lean liquid pump (8) arranged between the lean-rich liquid heat exchanger (5) and the absorption tower (1) through a pipeline; the supergravity desorption device (3) and the heat recovery device (4) are connected through a pipeline; The humidifying section (9) and the water washing section (10) are arranged at the top of the absorption tower (1), and the humidifying section (9) and the water washing section (10) are used to humidify the flue gas and cool the flue gas washing water, respectively; an aerosol growth section (14) is provided at the end of the water washing section (10); and a reboiler (15) is connected to the bottom of the supergravity desorption device (3); The water washing section (10) is provided with a water washing pump (13). The water washing pump (13), the rich liquid pump (6), the first lean liquid pump (7) and the second lean liquid pump (8) are connected to a controller. The controller adjusts the flow rate of each pump according to the rich liquid temperature, the regeneration gas temperature, the absorption tower load and the flue gas composition.

2. The high-gravity carbon dioxide capture system according to claim 1, characterized in that: The heat recovery device (4) is arranged on the top of the supergravity desorption device (3), and the lean-rich liquid heat exchanger (5) is arranged between the absorption tower (1) and the supergravity desorption device (3).

3. The high-gravity carbon dioxide capture system according to claim 1, characterized in that: A flue gas inlet is provided on the surface of the absorption tower (1), and the flue gas inlet is connected to a fan (2).

4. The high-gravity carbon dioxide capture system according to claim 1, wherein: The lean-rich liquid heat exchanger (5) is provided with a first lean liquid inlet connected to the liquid outlet of the first lean liquid pump (7), and a second lean liquid outlet connected to the liquid inlet of the second lean liquid pump (8); the absorption tower (1) is provided with a lean liquid inlet connected to the liquid outlet of the second lean liquid pump (8).

5. The high-gravity carbon dioxide capture system according to claim 1, wherein: The water washing section (10) includes a storage tank (11) connected to the absorption tower (1) and the aerosol growth section (14) through a pipeline, and a water washing cooler (12) and a water washing pump (13) arranged between the storage tank (11) and the absorption tower (1).

6. A method for controlling a high-gravity carbon dioxide capture system, characterized in that: A high-gravity carbon dioxide capture system as described in any one of claims 1 to 5 is used, including: a control strategy for adjusting the water wash pump, the rich liquid pump, the first lean liquid pump and the second lean liquid pump according to the rich liquid temperature, the regeneration gas temperature, the absorption tower load and the flue gas composition.

7. The method for controlling a high-gravity carbon dioxide capture system according to claim 6, wherein: When the rich liquid temperature rises above a preset upper limit, the flow rate of the first lean liquid pump (7) is increased to transport more hot lean liquid to the lean-rich liquid heat exchanger (5), and at the same time, the flow rate of the second lean liquid pump (8) is increased to transport more cooled lean liquid back to the absorption tower (1); when the rich liquid temperature is lower than a preset lower limit, the flow rate of the first lean liquid pump (7) is reduced to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger (5), and the flow rate of the second lean liquid pump (8) is reduced to reduce the amount of cooled lean liquid refluxed to the absorption tower (1).

8. The method for controlling a high-gravity carbon dioxide capture system according to claim 6, wherein: When the regeneration gas temperature is higher than the preset regeneration gas temperature upper limit, the flow rate of the first lean liquid pump (7) is increased to transport more hot lean liquid to the lean-rich liquid heat exchanger (5), and the flow rate of the second lean liquid pump (8) is increased to transport the cooled lean liquid back to the absorption tower (1); when the regeneration gas temperature is lower than the preset regeneration gas temperature lower limit, the flow rate of the first lean liquid pump (7) is reduced to reduce the amount of hot lean liquid entering the lean-rich liquid heat exchanger (5), and the flow rate of the second lean liquid pump (8) is reduced to reduce the amount of cooled lean liquid refluxed to the absorption tower (1).

9. The method for controlling a high-gravity carbon dioxide capture system according to claim 6, wherein: When the load of the absorption tower (1) increases, the flow rate of the first lean liquid pump (7) is increased, and the flow rate of the second lean liquid pump (8) is increased to transport more cooled lean liquid back to the absorption tower (1), and the flow rate of the water washing pump (13) is increased to ensure that sufficient cooling water enters the water washing section (10) to maintain the temperature of the washing water; when the load of the absorption tower (1) decreases, the flow rate of the first lean liquid pump (7) is reduced, and the flow rate of the second lean liquid pump (8) is reduced to reduce the amount of cooled lean liquid refluxed to the absorption tower (1), and the flow rate of the water washing pump (13) is reduced to reduce the amount of cooling water entering the water washing section (10).

10. The method for controlling a high-gravity carbon dioxide capture system according to claim 6, wherein: When the CO2 concentration in the flue gas increases and / or the flue gas flow rate increases, the flow rate of the first lean liquid pump (7) and the flow rate of the second lean liquid pump (8) are increased to transport more cooled lean liquid back to the absorption tower (1), and the flow rate of the water washing pump (13) is increased to ensure that sufficient cooling water enters the water washing section (10); When the concentration of particulate matter or aerosol in the flue gas increases, the flow rate of the water washing pump (13) is increased to ensure that sufficient cooling water enters the water washing section (10), and the regeneration gas heating power of the humidification section (9) is increased to promote the growth and removal of particulate matter and aerosol.

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