Coal power exhaust smoke carbon capture and carbon dioxide energy storage integrated system and control method thereof

Abstract

The invention discloses a coal power exhaust smoke carbon capture and carbon dioxide energy storage integrated system and a control method thereof, and relates to the technical field of energy conservation, carbon reduction, energy storage and the like of a coal power unit, in particular to the coal power exhaust smoke carbon capture and carbon dioxide energy storage integrated system and the control method thereof. Comprising an adsorption separation tower module, a compressor, a carbon dioxide high-pressure storage tank and a turbine in sequence, and the boiler smoke exhaust pipeline is connected between the turbine and the adsorption separation tower module; the plurality of heat exchangers are respectively arranged between the boiler smoke exhaust pipeline and the adsorption separation tower module, between the compressor and the carbon dioxide high-pressure storage tank and between the carbon dioxide high-pressure storage tank and the turbine. The method has the advantages that the carbon capture capacity is enhanced, the operation flexibility is improved, the energy utilization efficiency is improved, the peak output capacity is enhanced, and renewable energy integration, economic benefits, social benefits and resource recycling are promoted.

Description

Technical Field

[0001] The present invention relates to the technical fields of energy conservation, carbon reduction, energy storage and the like of coal-fired power units, and in particular to an integrated system for coal-fired power plant exhaust carbon capture and carbon dioxide energy storage and a control method thereof. Background Art

[0002] The present invention relates to the fields of energy conservation and carbon reduction, energy storage technology, etc., especially in the efficient operation and carbon emission control of coal-fired power units. With the transformation of the global energy structure and the enhancement of environmental protection awareness, reducing the carbon emissions of coal-fired power units and improving their operational flexibility have become urgent issues that need to be addressed. Existing coal-fired power unit technology and carbon capture and utilization technology (CCUS) have the following shortcomings: 1. Limited operational flexibility: Traditional coal-fired power units are mainly designed for base load power generation and are difficult to adapt to the grid's demand for rapid response and deep peak load regulation. This not only affects the stability of the power system, but also limits the competitiveness of coal-fired power units in the power market where the proportion of renewable energy is gradually increasing.

[0003] 2. Challenges in carbon emission control: Coal-fired power units are one of the main sources of carbon dioxide emissions. Although the existing CCUS technology can capture carbon dioxide, it has problems such as high energy consumption, high cost, and limited capture efficiency, which limits its large-scale application.

[0004] 3. Low energy efficiency: During the operation of coal-fired power units, waste heat resources are not effectively utilized, resulting in low overall energy efficiency. In addition, when coal-fired power units operate at partial load, their efficiency drops significantly, further increasing energy consumption and carbon emissions.

[0005] 4. Insufficient peak load regulation and peak capacity: Due to the inherent characteristics of coal-fired power units, the peak load regulation capacity is limited during the peak load period in summer, making it difficult to meet the grid's demand for peak output. This not only affects the supply and demand balance of the power system, but also increases the operating cost of the power system.

[0006] 5. Integration of renewable energy: With the rapid development of renewable energy such as wind power and photovoltaic power, its intermittency and instability have brought new challenges to the power system. How to effectively integrate renewable energy and reduce its impact on the power grid is one of the important issues facing the current power system.

[0007] Therefore, developing a comprehensive processing system that can improve the operating flexibility of coal-fired power units, reduce carbon emissions, effectively utilize waste heat resources, and enhance peak-shaving and peak-peaking capabilities is of great significance for achieving low-carbon transformation and sustainable development of the power system. Summary of the invention

[0008] The present invention aims to overcome the above-mentioned shortcomings of the prior art and provide an integrated system for coal-fired power plant exhaust carbon capture and carbon dioxide energy storage and a control method thereof.

[0009] The technical solution adopted by the present invention is as follows: An integrated system for coal-fired power plant exhaust carbon capture and carbon dioxide energy storage, comprising: a boiler exhaust pipe, a plurality of heat exchangers, and a circulation pipeline sequentially composed of an adsorption separation tower module, a compressor, a carbon dioxide high-pressure storage tank, and a turbine, wherein the boiler exhaust pipe is connected between the turbine and the adsorption separation tower module; A plurality of heat exchangers are respectively arranged between the boiler exhaust pipe and the adsorption separation tower module, between the compressor and the carbon dioxide high-pressure storage tank, and between the carbon dioxide high-pressure storage tank and the turbine.

[0010] Furthermore, the adsorption separation tower module includes at least two adsorption separation towers, and an inter-tower heat exchanger is arranged between the adsorption separation towers.

[0011] Furthermore, the adsorption separation tower module is independently provided with a smoke inlet and a smoke outlet outside the circulation pipeline.

[0012] Furthermore, a plurality of heat exchangers are separately provided with heat exchange pipelines outside the circulation pipeline.

[0013] Furthermore, a plurality of heat exchangers are provided between the compressor and the carbon dioxide high-pressure storage tank.

[0014] Furthermore, it includes a control system, a boiler exhaust pipe, a heat exchanger, an adsorption separation tower module, a compressor, a carbon dioxide high-pressure storage tank and a permeate, which are electrically connected to the control system.

[0015] Furthermore, the circulation pipeline is provided with a plurality of one-way valves.

[0016] Furthermore, a control method for an integrated system of coal-fired power exhaust carbon capture and carbon dioxide energy storage comprises the following steps: S1: When the system is first started, the flue gas from the boiler is cooled by heat exchange with the heat exchanger and the condensate of the steam turbine and then flows into the adsorption separation tower module. The carbon dioxide in the flue gas is adsorbed and the remaining gas is discharged through the smoke outlet; S2: When one of the adsorption separation towers is saturated, the control system switches the flue gas to another adsorption separation tower to start adsorption separation; S3: A stream of high-temperature flue gas or steam is introduced from the flue gas inlet into the adsorption separation tower with saturated adsorption to increase its temperature, whereby carbon dioxide is desorbed and flows into the compressor for pressurization, and then is cooled into liquid after heat exchange in the heat exchanger and stored in a high-pressure storage tank; S4: When desorption is completed in one of the adsorption separation towers, the other adsorption separation tower completes adsorption. The control system transfers the heat of the adsorption separation tower that has completed desorption to the adsorption separation tower to be desorbed through the inter-tower heat exchanger, so that the carbon dioxide therein starts to be desorbed and input into the compressor to complete liquefaction storage. At the same time, the adsorption separation tower that has completed desorption is cooled down and starts to adsorb carbon dioxide in the flue gas again, and the cycle repeats. S5: In the subsequent operation, due to the inevitable heat exchange loss of the inter-tower heat exchanger, the control system injects high-temperature flue gas or steam through the smoke inlet to supplement the heat of the adsorption separation tower module according to the amount of heat loss.

[0017] Furthermore, when the coal-fired power unit is operating with zero power supply: on the basis of the operation of carbon capture to produce liquid carbon dioxide, in order to consume all the electricity of the coal-fired power unit after deducting the factory power consumption, the control system increases the compressor speed, increases the compressor power consumption, and realizes zero power supply operation without stopping; at this time, the control system adjusts the input flue gas volume to ensure that the adsorption and desorption rates of the two towers in the system remain consistent.

[0018] Furthermore, when the coal-fired power unit is in peak operation: on the basis of producing liquid carbon dioxide, the control system controls the high-pressure carbon dioxide stored in the high-pressure storage tank to flow into the turbine to expand and generate power after absorbing heat through the heat exchanger. The low-pressure carbon dioxide that has completed the work is merged into the boiler exhaust pipe, and after being cooled by heat exchange with condensate through the heat exchanger, it flows into the adsorption separation tower in the adsorption state for adsorption and storage. At this time, the input flue gas flow is adjusted by the control system so that the adsorption rate and desorption rate of the two towers are consistent.

[0019] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. Enhanced carbon capture capability: The system has a highly efficient carbon capture function, which can realize the continuous and stable capture, separation, compression and liquefaction storage of carbon dioxide (CO2) in the flue gas of coal-fired power units. Compared with the traditional CCUS system, the use of low-pressure adsorption technology to separate and store CO2 in the flue gas greatly reduces the floor space and investment cost, and realizes the market application of large-scale energy storage matching large-power coal-fired power units, which helps to significantly reduce the carbon emissions of coal-fired power units and is in line with the global trend of low-carbon economic development.

[0020] 2. Improve operational flexibility: The system significantly enhances the peak load regulation capability of coal-fired power units by integrating turbine power generation systems and advanced control systems. It can achieve zero power supply operation without stopping the machine, as well as rapid conversion between low load and peak load, thus improving the stability and responsiveness of the power system.

[0021] 3. Improve energy efficiency: Through the optimized design of the heat exchanger system, the system can effectively recycle the waste heat resources in the boiler exhaust gas, significantly improving the overall energy efficiency of the coal-fired power unit. This not only reduces energy waste, but also reduces operating costs.

[0022] 4. Enhance peak output capacity: During peak load periods, the system can release the stored high-pressure carbon dioxide, which is then expanded by the turbine to generate electricity, effectively increasing the peak output capacity of the coal-fired power units and meeting the grid’s demand for peak power.

[0023] 5. Promote the integration of renewable energy: The system can use low-cost wind power and photovoltaic power and other renewable energy sources that cannot be connected to the grid as the power source of the compressor, further reducing the coal consumption and carbon emissions of coal-fired power units. At the same time, by converting renewable energy into high-quality electricity for grid connection, the utilization efficiency of renewable energy is improved.

[0024] 6. Economic and social benefits: By improving the operational flexibility and carbon emission control capabilities of coal-fired power units, the system can bring significant economic and social benefits to power plants. In addition, by reducing carbon emissions and optimizing the energy structure, it helps achieve the country's energy conservation and emission reduction goals and sustainable development strategies.

[0025] 7. Resource recycling: The captured carbon dioxide can not only be stored for industrial production, such as carbonated beverages, food processing, chemical raw materials, etc., but also can be used for long-term carbon fixation through geological storage and other methods, further promoting the development of the carbon circular economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the structure of the present invention; Markings in the figure: 1-circulation pipeline, 2-adsorption separation tower module, 3-adsorption separation tower, 4-compressor, 5-heat exchanger, 6-high-pressure storage tank, 7-turbine, 8-boiler exhaust pipe, 9-inter-tower heat exchanger, 10-smoke inlet, 11-smoke outlet, 12-heat exchange pipeline. DETAILED DESCRIPTION

[0027] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] Embodiment 1 In this embodiment, if Figure 1As shown, a coal-fired power exhaust carbon capture and carbon dioxide energy storage integrated system includes: a boiler exhaust pipe 8, a plurality of heat exchangers 5 and a circulation pipeline 1 composed of an adsorption separation tower module 2, a compressor 4, a carbon dioxide high-pressure storage tank 6 and a turbine 7 in sequence, and the boiler exhaust pipe 8 is connected between the turbine 7 and the adsorption separation tower module 2; The plurality of heat exchangers 5 are respectively arranged between the boiler exhaust pipe 8 and the adsorption separation tower module 2 , between the compressor 4 and the carbon dioxide high-pressure storage tank 6 , and between the carbon dioxide high-pressure storage tank 6 and the turbine 7 .

[0030] Specifically, the circulation pipeline 1 is arranged as follows: the turbine 7 is connected to the first heat exchanger 5, the first heat exchanger 5 is introduced into the turbine condensate through the heat exchange pipeline 12, the first heat exchanger 5 is connected to the adsorption separation tower module 2, the adsorption separation tower module 2 is connected to the compressor 4, the second heat exchanger 5 and the third heat exchanger 5 are connected between the compressor 4 and the high-pressure storage tank 6, the second heat exchanger 5 and the third heat exchanger 5 are introduced into the turbine feed water and the turbine condensate respectively through the heat exchange pipeline 12 to realize multi-stage heat exchange and make full use of thermal energy, the high-pressure storage tank 6 is connected to the fourth heat exchanger 5, the fourth heat exchanger 5 is introduced into the boiler high-temperature flue gas or the turbine high-temperature steam through the heat exchange pipeline 12, and the fourth heat exchanger 5 is connected to the turbine 7 to form a circulation pipeline 1.

[0031] Furthermore, the adsorption separation tower module 2 includes at least two adsorption separation towers 3 , and an inter-tower heat exchanger 9 is disposed between the adsorption separation towers 3 .

[0032] In this embodiment, the adsorption separation tower module 2 includes two adsorption separation towers 3, and the two adsorption separation towers 3 are operated alternately. The carbon dioxide adsorption separation tower module 2 in the system includes two adsorption separation towers 3 arranged in parallel, and a heat exchanger 5 is arranged between the two towers to realize heat exchange between the two towers. The two towers alternately serve as the heat source for desorption of each other, and the module basically realizes internal heat self-sustaining, and completes the continuous carbon capture of the input exhaust gas. Among them, the adsorption separation tower module 2 realizes that the two towers alternately serve as cold or heat sources to each other by designing two towers in parallel and matching the inter-tower heat exchanger 9 and the corresponding pipeline connection of the valve, so as to realize the alternating operation of exhaust carbon dioxide adsorption separation and carbon dioxide desorption in the two groups of adsorption separation towers 3, thereby realizing the continuous and efficient carbon capture of the exhaust gas of the coal power plant and producing liquid carbon dioxide.

[0033] Furthermore, the adsorption separation tower module 2 is separately provided with a smoke inlet 10 and a smoke outlet 11 outside the circulation pipeline 1 .

[0034] The smoke inlet 10 is used to input high-temperature smoke or steam to supplement the heat of the adsorption separation tower module 2, and the smoke outlet 11 is used to discharge other gases after the adsorption of carbon dioxide, so as to fully utilize the hot steam of the steam turbine unit and improve the energy utilization efficiency.

[0035] Furthermore, the plurality of heat exchangers 5 are separately provided with a heat exchange pipeline 12 outside the circulation pipeline 1 .

[0036] It is used to introduce high-temperature flue gas from boilers or high-temperature steam from turbines, condensate from turbines, feed water, etc., to fully utilize the heat in the system and improve energy efficiency.

[0037] Furthermore, a plurality of heat exchangers 5 are provided between the compressor 4 and the carbon dioxide high-pressure storage tank 6 .

[0038] As the core component of the compression device, the compressor 4 can compress the captured carbon dioxide to increase its pressure and density for subsequent storage and utilization. This design ensures the efficiency and stability of the compression process and improves the carbon emission control capability of the system.

[0039] Multi-stage heat exchange system makes full use of heat energy and improves the unit operation efficiency: As the core component of the waste heat recovery device, the heat exchanger 5 can effectively recover the waste heat resources in the flue gas and transfer it to other devices for utilization through the heat exchange medium. This design improves the overall thermal efficiency of the system.

[0040] Furthermore, including a control system, the boiler exhaust pipe 8, the heat exchanger 5, the adsorption separation tower module 2, the compressor 4, the carbon dioxide high-pressure storage tank 6 and the turbine 7 are all electrically connected to the control system.

[0041] Used to control the overall system and perform different controls according to different power generation conditions.

[0042] Furthermore, the circulation pipeline 1 is provided with a plurality of one-way valves.

[0043] The flow direction of the circulation pipeline 1 is effectively controlled to improve the system operation efficiency.

[0044] Embodiment 2 A control method for an integrated system of coal-fired power plant exhaust carbon capture and carbon dioxide energy storage, comprising the following steps: S1: When the system is first started, the flue gas from the boiler is cooled by heat exchange with the heat exchanger 5 and the condensate of the steam turbine and then flows into the adsorption separation tower module 2. The carbon dioxide in the flue gas is adsorbed and the remaining gas is discharged through the smoke outlet 11; S2: When one of the adsorption separation towers 3 is saturated with adsorption, the control system switches the flue gas to another adsorption separation tower 3 to start adsorption separation; S3: A stream of high-temperature flue gas or steam is introduced from the smoke inlet 10 into the adsorption separation tower 3 which is saturated with adsorption to increase its temperature, wherein carbon dioxide is desorbed and flows into the compressor 4 for pressurization, and then is cooled into liquid after heat exchange in the heat exchanger 5 and stored in the high-pressure storage tank 6; S4: When the desorption of one of the adsorption separation towers 3 is completed, the other adsorption separation tower 3 is completed. The control system transfers the heat of the adsorption separation tower 3 that has completed desorption to the adsorption separation tower 3 to be desorbed through the inter-tower heat exchanger 9, so that the carbon dioxide therein starts to be desorbed and is input into the compressor 4 to complete liquefaction and storage. At the same time, the adsorption separation tower 3 that has completed desorption is cooled down and starts to adsorb carbon dioxide in the flue gas again, and the cycle repeats. S5: In the subsequent operation, due to the inevitable heat exchange loss of the inter-tower heat exchanger 9, the control system inputs high-temperature flue gas or steam through the smoke inlet 10 to supplement the heat of the adsorption separation tower module 2 according to the amount of heat loss.

[0045] Carbon capture to produce liquid carbon dioxide: When the system is started for the first time, the flue gas from the boiler exhaust pipe 8 is cooled by heat exchange with the heat exchanger 5 and the turbine condensate, and then flows into the adsorption separation tower module 2. The carbon dioxide in the flue gas is adsorbed and the remaining gas is discharged. When the adsorption of the first adsorption separation tower 3 is completed, the control system switches the flue gas to flow into the second adsorption separation tower 3 to start adsorption separation; at the same time, a stream of high-temperature flue gas or steam is introduced into the first adsorption separation tower 3 to heat up the carbon dioxide therein so as to desorb it, and then flows into the compressor 4 for pressurization, and then passes through the second and third heat exchangers 5 respectively. After heat exchange with turbine feed water and condensate, it is cooled to liquid and stored in high-pressure storage tank 6; when the first adsorption separation tower 3 is completely desorbed, the second adsorption separation tower 3 is also just adsorbed, and the flue gas is switched back to the first adsorption separation tower 3 again, and the heat in the first adsorption separation tower 3 is transported to the second adsorption separation tower 3 through the inter-tower heat exchanger 9, so that the carbon dioxide in the second adsorption separation tower 3 begins to desorb and enter the compressor 4, and at the same time, the first adsorption separation tower 3 starts to adsorb carbon dioxide in the flue gas after cooling, and the cycle is repeated to achieve continuous operation of flue gas carbon capture and liquid carbon dioxide production. In the subsequent operation, due to the inevitable heat exchange loss of the inter-tower heat exchanger 9, high-temperature flue gas or steam is intermittently added to supplement the heat of the adsorption separation tower module 2.

[0046] Embodiment 3 When the coal-fired power unit is in zero-power operation: on the basis of the operation of carbon capture to produce liquid carbon dioxide, in order to consume all the electricity of the coal-fired power unit after deducting the factory power consumption, the control system increases the speed of compressor 4, increases the power consumption of compressor 4, and realizes zero-power operation without stopping; at this time, the control system adjusts the input flue gas volume to ensure that the adsorption and desorption rates of the two towers in the system remain consistent.

[0047] When the unit needs to be shut down due to the start-stop peak load regulation, by increasing the speed of compressor 4 and increasing the compression power, the coal-fired power unit is reduced to the minimum load, and the remaining output except for the factory power consumption is all used to drive compressor 4, so that the coal-fired power unit can be operated without stopping and with zero power supply, thus avoiding a large amount of energy loss caused by the start-stop of the coal-fired power unit. When the coal-fired power unit does not need to be shut down and only needs to operate at a low load, the minimum power supply load of the coal-fired power unit can also be further reduced by increasing the power consumption of compressor 4, thereby improving the deep peak load regulation capability of the coal-fired power unit. The pressurized high-temperature carbon dioxide is cooled by the two-stage heat exchanger 5 and stored in the storage tank for subsequent energy release process.

[0048] Embodiment 4 When the coal-fired power unit is in peak operation: on the basis of the operation of producing liquid carbon dioxide, the control system controls the high-pressure carbon dioxide stored in the high-pressure storage tank 6 to flow into the turbine 7 to expand and generate power after absorbing heat through the heat exchanger 5. The low-pressure carbon dioxide that has completed the work flows into the boiler exhaust pipe 8, and after being cooled by heat exchange with condensate through the heat exchanger 5, it flows into the adsorption separation tower 3 in the adsorption state for adsorption and storage. At this time, the input flue gas flow is adjusted by the control system so that the adsorption rate and desorption rate of the two towers are consistent.

[0049] When the coal-fired power unit needs to increase its power generation, the energy release part of the system is put into operation, and a stream of high-temperature flue gas or steam is introduced to heat the retained high-pressure carbon dioxide, which then enters the turbine 7 to expand and do work to drive the generator to generate electricity, thereby effectively improving the peak output capacity of the coal-fired power unit. According to the power plant's ramp rate requirements, the turbine 7 can be in a shutdown or hot standby state when it is not generating electricity. By dynamically adjusting the flow distribution in different operating modes, the adsorption and desorption rates of the two adsorption separation towers 3 are kept consistent, thereby achieving continuous and stable operation of the system.

[0050] In addition, if the power plant has the conditions to use low-priced wind power and photovoltaic power that cannot be connected to the grid as the power consumption of compressor 4, the profit can be further increased. The power consumption of compressor 4 is the low-priced wind power and photovoltaic power that cannot be connected to the grid, and the coal consumption of coal-fired power units is reduced under the same power generation load; when it is necessary to increase the peak output, the energy release system is operated, and turbine 7 generates electricity and connects to the grid, converting the low-priced wind power and photovoltaic power that cannot be connected to the grid into high-quality electricity for the grid, which can bring higher economic and social benefits to the power plant.

[0051] The above description is only a preferred embodiment of the invention and is not intended to limit the invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the invention should be included in the protection scope of the invention.

Claims

1. An integrated system for coal-fired power exhaust carbon capture and carbon dioxide energy storage, characterized in that: include: A boiler exhaust pipe (8), a plurality of heat exchangers (5) and a circulation pipeline (1) which is sequentially composed of an adsorption separation tower module (2), a compressor (4), a carbon dioxide high-pressure storage tank (6) and a turbine (7), wherein the boiler exhaust pipe (8) is connected between the turbine (7) and the adsorption separation tower module (2); The multiple heat exchangers (5) are respectively arranged between the boiler exhaust pipe (8) and the adsorption separation tower module (2), between the compressor (4) and the carbon dioxide high-pressure storage tank (6), and between the carbon dioxide high-pressure storage tank (6) and the turbine (7).

2. According to the integrated system of coal-fired power exhaust carbon capture and carbon dioxide energy storage as described in claim 1, it is characterized by: The adsorption separation tower module (2) comprises at least two adsorption separation towers (3), and an inter-tower heat exchanger (9) is arranged between the adsorption separation towers (3).

3. According to the integrated system of coal-fired power exhaust carbon capture and carbon dioxide energy storage as described in claim 1, it is characterized by: The adsorption separation tower module (2) is independently provided with a smoke inlet (10) and a smoke outlet (11) outside the circulation pipeline (1).

4. According to the coal-fired power exhaust carbon capture and carbon dioxide energy storage integrated system as described in claim 1, it is characterized by: The multiple heat exchangers (5) are independently provided with a heat exchange pipeline (12) outside the circulation pipeline (1).

5. According to the integrated system of coal-fired power exhaust carbon capture and carbon dioxide energy storage as described in claim 1, it is characterized by: A plurality of heat exchangers (5) are arranged between the compressor (4) and the carbon dioxide high-pressure storage tank (6).

6. According to the integrated system of coal-fired power exhaust carbon capture and carbon dioxide energy storage as described in claim 1, it is characterized by: It comprises a control system, wherein the boiler smoke exhaust pipe (8), the heat exchanger (5), the adsorption separation tower module (2), the compressor (4), the carbon dioxide high-pressure storage tank (6) and the turbine (7) are all electrically connected to the control system.

7. According to the coal-fired power exhaust carbon capture and carbon dioxide energy storage integrated system as described in claim 1, it is characterized by: The circulation pipeline (1) is provided with a plurality of one-way valves.

8. A control method for an integrated system of carbon capture and carbon dioxide energy storage for coal-fired power generation exhaust, applied to an integrated system of carbon capture and carbon dioxide energy storage for coal-fired power generation exhaust according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: When the system is started for the first time, the flue gas from the boiler is cooled by heat exchange with the condensate of the steam turbine in the heat exchanger (5) and then flows into the adsorption separation tower module (2). The carbon dioxide in the flue gas is adsorbed and the remaining gas is discharged through the smoke outlet (11); S2: When one of the adsorption separation towers (3) is saturated with adsorption, the control system switches the flue gas to another adsorption separation tower (3) to start adsorption separation; S3: A stream of high-temperature flue gas or steam is introduced from the flue gas inlet (10) into the adsorption separation tower (3) with saturated adsorption, so that the temperature is increased, and the carbon dioxide is desorbed and flows into the compressor (4) for pressurization, and then passes through the heat exchanger (5) for heat exchange and is cooled to liquid state and stored in the high-pressure storage tank (6); S4: When one of the adsorption separation towers (3) has completed desorption, the other adsorption separation tower (3) has completed adsorption, and the control system transfers the heat of the adsorption separation tower (3) that has completed desorption to the adsorption separation tower (3) to be desorbed through the inter-tower heat exchanger (9), so that the carbon dioxide therein starts to be desorbed and is input into the compressor (4) to complete liquefaction and storage. At the same time, the adsorption separation tower (3) that has completed desorption starts to adsorb carbon dioxide in the flue gas again after cooling down, and the cycle repeats. S5: In the subsequent operation, due to the inevitable heat exchange loss in the inter-tower heat exchanger (9), the control system inputs high-temperature flue gas or steam through the smoke inlet (10) to supplement the heat of the adsorption separation tower module (2) according to the amount of heat loss.

9. A control method for an integrated system of coal-fired power plant exhaust carbon capture and carbon dioxide energy storage according to claim 8, characterized in that: When the coal-fired power unit is in zero-power operation: on the basis of the operation of carbon capture to produce liquid carbon dioxide, in order to consume all the electricity of the coal-fired power unit after deducting the factory power consumption, the control system increases the speed of the compressor (4), increases the power consumption of the compressor (4), and realizes zero-power operation without stopping; at this time, the control system adjusts the input flue gas volume to ensure that the adsorption and desorption rates of the two towers in the system remain consistent.

10. The control method of the integrated system of coal-fired power exhaust carbon capture and carbon dioxide energy storage according to claim 8, characterized in that: When the coal-fired power unit is in peak operation: on the basis of the operation of producing liquid carbon dioxide, the control system controls the high-pressure carbon dioxide stored in the high-pressure storage tank (6) to flow into the turbine (7) to expand and generate power after absorbing heat through the heat exchanger (5). The low-pressure carbon dioxide that has completed the work flows into the boiler exhaust pipe (8), and after being cooled by heat exchange with condensed water through the heat exchanger (5), it flows into the adsorption separation tower (3) in the adsorption state for adsorption and storage. At this time, the control system adjusts the input flue gas flow rate so that the adsorption rate and desorption rate of the two towers are consistent.

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