Rapid start-stop carbon capture system suitable for peak-shaving unit, and rapid start-stop method

Abstract

Disclosed in the present disclosure are a rapid start-stop carbon capture system suitable for a peak-shaving unit and a rapid start-stop method. The rapid start-stop carbon capture system suitable for a peak-shaving unit comprises an absorption tower, a desorption tower, a heat exchanger and a carbon capture treatment assembly, wherein the heat exchanger is connected between the absorption tower and the desorption tower, and the carbon capture treatment assembly is connected to a carbon dioxide outlet of the desorption tower; and the absorption tower has a first electric heating assembly, and the desorption tower has a second electric heating assembly and a reboiler, the first electric heating assembly being configured to heat a first working medium in the absorption tower, and the second electric heating assembly and the reboiler being configured to heat a second working medium in the desorption tower.

Description

Carbon capture system and method for rapid start and stop suitable for rapid start and stop of peak regulation unit

[0001] Cross-reference to Related Applications

[0002] The present application is based on and claims priority to Chinese Patent Application No. 202410590927.9, filed on May 13, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure belongs to the technical field of carbon capture, and specifically relates to a carbon capture system and method for rapid start and stop suitable for rapid start and stop of a peak regulation unit. BACKGROUND

[0004] In related technologies, a carbon capture system generally relies on a conventional coal-fired power plant unit, rather than a peak regulation unit. However, with the increasing demand for peak regulation of thermal power plants, the carbon capture system also needs to start and stop with the peak regulation of thermal power units, facing frequent start and stop requirements. However, it takes a long time for the carbon capture system to reach the expected temperature when starting, and the entire system needs to reach a stable state, which will seriously affect the capture efficiency of the carbon capture system and increase the system energy consumption due to uneven heat exchange in the case of frequent start and stop.

[0005] In addition, the high-temperature steam of the power plant is used to heat the rich liquid in the desorption tower through the reboiler to regenerate it. However, the stability of the rich liquid pumping is affected, and the heat exchange effect is poor under the condition that the rich liquid flow entering the reboiler is unstable. SUMMARY

[0006] The present disclosure aims to at least partially solve one of the technical problems in the related art.

[0007] To this end, an embodiment of the present disclosure proposes a carbon capture system for rapid start and stop suitable for a peak regulation unit, which can improve the temperature rising speed of the absorption tower and the desorption tower in the carbon capture system, reduce the problem of poor heat exchange stability in the starting stage, realize rapid start of the carbon capture system, improve the carbon capture effect, and reduce the system energy consumption.

[0008] An embodiment of the present disclosure also proposes a method for rapid start and stop of a carbon capture system.

[0009] The carbon capture system for rapid start and stop suitable for a peak regulation unit according to an embodiment of the present disclosure includes an absorption tower, a desorption tower, a heat exchanger, and a carbon capture processing assembly. The heat exchanger is connected between the absorption tower and the desorption tower, and is used to exchange heat of a first working medium entering the absorption tower from the desorption tower and a second working medium entering the desorption tower from the absorption tower. The carbon capture processing assembly is connected with a carbon dioxide outlet of the desorption tower.

[0010] The absorption tower has a first electric heating assembly, the desorption tower has a second electric heating assembly and a reboiler, the first electric heating assembly is used for heating a first working medium in the absorption tower, and the second electric heating assembly and the reboiler are used for heating the second working medium in the desorption tower.

[0011] The carbon capture system suitable for rapid start-stop of the peak regulation unit can heat and warm the solution in the absorption tower and the desorption tower through the first electric heating assembly and the second electric heating assembly in the initial stage of system start, can not only improve the warming speed of the absorption tower and the desorption tower in the carbon capture system, but also can make the solution be uniformly heated, has good heat exchange stability, reduces the problem of poor heat exchange stability due to unstable solution flow in the related technology, can realize rapid start of the carbon capture system, and thus improves the carbon capture effect and reduces system energy consumption.

[0012] In some embodiments, the number of the first electric heating assemblies is multiple, and the multiple first electric heating assemblies are arranged in the inner cavity of the absorption tower in the height direction of the absorption tower; and / or

[0013] The number of the second electric heating assemblies is multiple, and the multiple second electric heating assemblies are arranged in the inner cavity of the desorption tower in the height direction of the desorption tower.

[0014] In some embodiments, the first electric heating assembly and the second electric heating assembly each include a temperature control component for controlling the temperature of the corresponding electric heating assembly.

[0015] In some embodiments, the first electric heating assembly and the second electric heating assembly each include multiple electric heating wires, and the multiple electric heating wires are arranged in a grid shape.

[0016] In some embodiments, the temperature in the absorption tower is 40-50 DEG C, and the temperature in the desorption tower is 110-120 DEG C.

[0017] In some embodiments, the carbon capture system suitable for rapid start-stop of the peak regulation unit further includes a photovoltaic panel and an energy storage device, the photovoltaic panel is connected with the energy storage device, and the energy storage device is connected with the first electric heating assembly and the second electric heating assembly.

[0018] In some embodiments, the energy storage device includes:

[0019] A first storage tank having a first inlet and a first outlet;

[0020] a first compressor, an inlet end of the first compressor being connected with a carbon dioxide outlet of the desorption tower, an outlet end of the first compressor being connected with the first inlet, the first compressor having a driving part, the driving part being connected with the photovoltaic panel;

[0021] a power generation component, the power generation component being connected with the first outlet of the first storage tank, the power generation component being connected with the first electric heating assembly and the second electric heating assembly to supply power to the first electric heating assembly and the second electric heating assembly.

[0022] In some embodiments, a first pipeline is provided between the inlet end of the first compressor and the carbon dioxide outlet of the desorption tower, a first valve being provided on the first pipeline; and / or

[0023] a second pipeline is provided between the carbon dioxide outlet of the desorption tower and the inlet end of the carbon capture and processing assembly, a second valve being provided on the second pipeline; and / or

[0024] the power generation component comprises a turbine and a generator, an inlet end of the turbine being connected with the first outlet of the first storage tank, an outlet end of the turbine being connected with the inlet end of the carbon capture and processing assembly, the turbine being drivingly connected with the generator to drive the generator to work; and / or

[0025] the first storage tank has a second outlet, a second storage tank being connected with the second outlet.

[0026] In some embodiments, the carbon capture system suitable for rapid start-stop of the peak regulation unit further comprises a third storage tank, an inlet end of the third storage tank being connected with the carbon dioxide outlet of the desorption tower, an outlet end of the third storage tank being connected with the inlet end of the first compressor and the inlet end of the carbon capture and processing assembly; and / or

[0027] the carbon capture and processing assembly comprises a second compressor; and / or

[0028] the photovoltaic panel is arranged on a top of the first storage tank; and / or

[0029] the carbon capture system suitable for rapid start-stop of the peak regulation unit further comprises a heat storage assembly, the heat storage assembly being used for storing heat released when the first compressor compresses carbon dioxide, and the heat storage assembly being used for heating carbon dioxide discharged from the first outlet of the first storage tank.

[0030] The carbon capture system rapid start-stop method according to the embodiments of the present disclosure is used for rapid start-stop operation of the carbon capture system suitable for rapid start-stop of the peak regulation unit in any one of the above embodiments, and comprises the following steps:

[0031] the photovoltaic panel receives sunlight and converts it into electric energy;

[0032] Part of the gaseous carbon dioxide discharged by the thermal power unit is compressed into liquid carbon dioxide by the electric energy provided by the photovoltaic panel to achieve energy storage;

[0033] After the peak-shaving unit is started, the liquid carbon dioxide is used to drive the turbine to operate and drive the generator to generate electricity to electrically heat the solutions in the absorption tower and the desorption tower;

[0034] When the temperature of the solution in the absorption tower reaches a first preset threshold and the temperature of the solution in the desorption tower reaches a second preset threshold, the turbine and the generator are turned off;

[0035] The solution entering the desorption tower is heated by the reboiler to maintain the temperature of the solutions in the absorption tower and the desorption tower, so that the carbon capture system can be quickly started. BRIEF DESCRIPTION OF DRAWINGS

[0036] Fig. 1 is a structural schematic diagram of a carbon capture system suitable for quick start and stop of a peak-shaving unit according to an embodiment of the present disclosure.

[0037] Fig. 2 is a flowchart of a method for quick start and stop of a carbon capture system according to an embodiment of the present disclosure.

[0038] Reference signs: 1, absorption tower; 2, desorption tower; 21, carbon dioxide outlet; 3, energy storage device; 31, first storage tank; 311, first outlet; 312, second outlet; 32, photovoltaic panel; 33, first compressor; 34, turbine; 35, generator; 36, electric motor; 41, first electric heating assembly; 42, second electric heating assembly; 43, temperature control component; 5, heat exchanger; 61, first pipeline; 62, first valve; 63, second pipeline; 64, second valve; 71, third storage tank; 72, second compressor. DETAILED DESCRIPTION

[0039] The embodiments of the present disclosure are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present disclosure, and cannot be understood as a limitation of the present disclosure.

[0040] As shown in Fig. 1, the carbon capture system suitable for quick start and stop of a peak-shaving unit according to an embodiment of the present disclosure includes an absorption tower 1, a desorption tower 2, a heat exchanger 5 and a carbon capture processing assembly, the heat exchanger 5 is connected between the absorption tower 1 and the desorption tower 2, the heat exchanger 5 is used to heat the first working medium entering the absorption tower 1 from the desorption tower 2 and the second working medium entering the desorption tower 2 from the absorption tower 1, and the carbon capture processing assembly is connected with the carbon dioxide outlet 21 of the desorption tower 2.

[0041] The first working medium is lean liquid, and the second working medium is rich liquid. The flue gas containing carbon dioxide gas is introduced into the absorption tower 1 and reacts with the lean liquid introduced into the absorption tower 1. The lean liquid absorbs the carbon dioxide gas to form rich liquid. The flue gas from which the carbon dioxide is absorbed is discharged from the top of the absorption tower 1. The rich liquid at the bottom of the absorption tower 1 is transported into the desorption tower 2. After the rich liquid enters the desorption tower 2, the rich liquid is heated by the reboiler and desorbs the carbon dioxide gas to form lean liquid. The desorbed carbon dioxide gas is discharged from the carbon dioxide outlet 21 at the top of the desorption tower 2. The solutions in the absorption tower 1 and the desorption tower 2 are circulated through the heat exchanger 5. The lean liquid and the rich liquid are heat exchanged in the heat exchanger 5 to improve the utilization rate of heat and maintain the balance of the system.

[0042] The carbon dioxide desorbed from the desorption tower 2 is discharged from the carbon dioxide outlet 21 of the desorption tower 2 and subjected to subsequent centralized processing and application by the carbon capture processing assembly.

[0043] The absorption tower 1 of the embodiment of the present disclosure has a first electric heating assembly 41, and the desorption tower 2 has a second electric heating assembly 42 and a reboiler. The first electric heating assembly 41 is used to heat the first working medium in the absorption tower 1. The second electric heating assembly 42 and the reboiler are used to heat the second working medium in the desorption tower 2.

[0044] It should be understood that the carbon capture system uses the steam of the power plant to heat the rich liquid through the reboiler in the desorption tower 2, thereby ensuring the balance of the system and ensuring that the rich liquid can desorb the carbon dioxide gas in the desorption tower 2. However, at the initial stage of starting the carbon capture system, the solution temperature of the lean liquid and the rich liquid is low, which cannot meet the normal operation of the system. In addition, due to the poor stability of the rich liquid pump and the unstable flow, the temperature rising speed of the system is also affected. Based on only using the steam of the power plant as a heat source, the carbon capture system starts slowly, the carbon capture effect is poor, and the system energy consumption is large.

[0045] In the embodiment of the present disclosure, the first electric heating assembly 41 and the second electric heating assembly 42 are arranged to directly heat the solution by using the electric heating assemblies arranged in the desorption tower 2 and the absorption tower 1, thereby improving the stability and effect of heat exchange, and realizing the rapid start of the carbon capture system.

[0046] In the embodiment of the present disclosure, the electric auxiliary heating mode is adopted to rapidly reach the optimal reaction temperature range of the absorption tower 1 and the desorption tower 2, thereby effectively shortening the time required for balancing the capture system. For example, the resistance wire heating layer is used for heating, which is equivalent to direct heating, and the influence of the flow rate of the rich liquid on the heat exchange effect can be excluded.

[0047] The embodiment of the present disclosure can use the electric heating assembly to rapidly heat the solution at the start-up stage of the carbon capture system. After the carbon capture system normally operates, the reboiler is used to ensure the balance of the system.

[0048] In some embodiments, the number of the first electric heating assemblies 41 is multiple, and the multiple first electric heating assemblies 41 are arranged in the inner cavity of the absorption tower 1 along the height direction of the absorption tower 1 at intervals. The number of the second electric heating assemblies 42 is multiple, and the multiple second electric heating assemblies 42 are arranged in the inner cavity of the desorption tower 2 along the height direction of the desorption tower 2 at intervals.

[0049] It should be understood that arranging multiple first electric heating assemblies 41 in the absorption tower 1 can be adjusted according to the optimal absorption range of different carbon capture solvents, and the temperature can be accurately controlled in the optimal temperature range in which the chemical equilibrium reaction proceeds in the forward direction, generally between 40°C and 50°C, so that the optimal reaction conditions in the absorption tower 1 are quickly reached, and the capture efficiency when the machine is started is effectively ensured.

[0050] Arranging multiple second electric heating assemblies 42 in the desorption tower 2 can be adjusted according to the optimal desorption range of different carbon capture solvents, and the temperature can be accurately controlled in the optimal temperature range in which the chemical equilibrium reaction proceeds in the reverse direction, generally between 110°C and 120°C, so that the optimal reaction conditions in the desorption tower 2 are quickly reached, and the desorption efficiency when the machine is started is effectively ensured.

[0051] In addition, the multiple first electric heating assemblies 41 and the multiple second electric heating assemblies 42 can be arranged in multiple layers at intervals, can sufficiently and uniformly heat the system solution, and can also play the role of a filler layer, increase the time of gas-liquid contact and stay, and improve the absorption effect of carbon dioxide gas in the absorption tower 1 and the desorption effect of carbon dioxide gas in the desorption tower 2.

[0052] The multiple first electric heating assemblies 41 and the multiple second electric heating assemblies 42 can form gradient temperature heating, can optimize the absorption and desorption effects according to the temperature of different positions of the absorption tower 1 and the desorption tower 2 in the height direction, reduce energy consumption, and improve the heat exchange effect.

[0053] In some embodiments, the first electric heating assembly 41 and the second electric heating assembly 42 each include a temperature control component 43 for controlling the temperature of the corresponding electric heating assembly. That is, the temperature of a single electric heating assembly is accurately controlled by using the temperature control component 43, which can ensure that the temperature in the absorption tower 1 and the desorption tower 2 is within the optimal reaction interval.

[0054] The temperature control component 43 can be a voltage regulator, which controls the voltage of different electric heating assemblies to adjust the temperature of the corresponding electric heating assembly.

[0055] In some embodiments, the first electric heating assembly 41 and the second electric heating assembly 42 each include a plurality of electric heating wires arranged in a grid shape. It should be noted that the first electric heating assembly 41 and the second electric heating assembly 42 are arranged in a grid shape by the electric heating wires, which can improve their role as a filler layer and facilitate the interval arrangement in the vertical direction in the absorption tower 1 and the desorption tower 2.

[0056] For example, the absorption tower 1 and the desorption tower 2 are cylindrical, and the first electric heating assembly 41 and the second electric heating assembly 42 are also circular electric heating mesh plates arranged in a grid shape, which are coaxially arranged with the absorption tower 1 and the desorption tower 2.

[0057] In some embodiments, the temperature in the absorption tower 1 is 40-50°C, and the temperature in the desorption tower 2 is 110-120°C. It should be understood that the optimal temperature range for the chemical reaction of the lean liquid with carbon dioxide in the absorption tower 1 is 40-50°C, and the optimal desorption temperature of the rich liquid in the desorption tower is 110-120°C.

[0058] In some embodiments, the carbon capture system suitable for the rapid start-stop of the peak regulation unit further includes a photovoltaic panel 32 and an energy storage device 3, the photovoltaic panel 32 is connected with the energy storage device 3, and the energy storage device 3 is connected with the first electric heating assembly 41 and the second electric heating assembly 42.

[0059] It should be noted that the photovoltaic panel 32 is used to generate electricity, so that the power plant does not need to provide additional electricity, reduces the regenerative energy consumption of the system, improves the economic benefits of carbon capture, and the energy storage device 3 is used to store the energy after the photovoltaic panel 32 receives sunlight. When the carbon capture system starts, the energy storage device 3 is used to supply power to the first electric heating assembly 41 and the second electric heating assembly 42.

[0060] In some embodiments, the energy storage device 3 includes a first storage tank 31, a first compressor 33, and a power generation component. The first storage tank 31 has a first inlet and a first outlet 311. The inlet end of the first compressor 33 is connected with the carbon dioxide outlet 21 of the desorption tower 2, and the outlet end of the first compressor 33 is connected with the first inlet. The first compressor 33 has a driving part connected with the photovoltaic panel 32. The power generation component is connected with the first outlet 311 of the first storage tank 31, and the power generation component is connected with the first electric heating assembly 41 and the second electric heating assembly 42 to supply power to the first electric heating assembly 41 and the second electric heating assembly 42.

[0061] It should be understood that, in the embodiments of the present disclosure, the gaseous carbon dioxide is compressed into liquid carbon dioxide by using the electric energy generated by the photovoltaic panel 32, and the energy is stored. In response to the start of the carbon capture system, the stored liquid carbon dioxide releases energy when it needs to be heated by the first electric heating assembly 41 and the second electric heating assembly 42, and the re-gasified carbon dioxide drives the power generation component to work, thereby generating electric energy to provide electric energy for the first electric heating assembly 41 and the second electric heating assembly 42.

[0062] The first compressor 33 has a driving part, which is an electric motor 36. The electric energy generated by the photovoltaic panel 32 drives the electric motor 36 to work, and then drives the first compressor 33 to work, so as to compress the gaseous carbon dioxide into liquid carbon dioxide.

[0063] In some embodiments, the power generation component includes a turbine 34 and a generator 35. The inlet end of the turbine 34 is connected with the first outlet 311 of the first storage tank 31, and the outlet end of the turbine 34 is connected with the inlet end of the carbon capture processing assembly. The turbine 34 is in transmission connection with the generator 35 to drive the generator 35 to work. That is, after the re-gasified carbon dioxide enters the turbine 34, the turbine 34 is driven to work, and the generator 35 is driven to work. The gaseous carbon dioxide after work enters the carbon capture processing assembly from the outlet end of the turbine 34, so as to guarantee the carbon capture effect of the whole system.

[0064] Further, the energy storage device 3 further includes a heat storage assembly. The heat storage assembly is used to store the heat released when the first compressor 33 compresses the carbon dioxide, and the heat storage assembly is used to heat the carbon dioxide discharged from the first outlet 311 of the first storage tank 31.

[0065] It should be understood that, when the electric energy generated by the photovoltaic panel 32 drives the first compressor 33 to compress the carbon dioxide, the carbon dioxide is liquefied and releases heat. The heat storage assembly can collect the heat generated in the compression process, so as to realize the decoupling conversion storage of the electric energy into the internal energy and heat energy of the carbon dioxide. In response to the need for the gasification of the liquid carbon dioxide and the driving of the turbine 34 to work, the heat collected by the heat storage assembly is used to heat and expand the gaseous carbon dioxide, so as to realize the coupling conversion of the internal energy and the heat energy of the carbon dioxide, and complete the energy release.

[0066] In some embodiments, the heat storage assembly can adopt a phase-change type heat storage device. When charging, the heat medium heats the phase-change material through the coil, the phase-change material absorbs heat, the temperature gradually rises to the phase-change temperature point, the phase-change material absorbs heat and changes phase, and the heat storage process is completed. When discharging, the cold medium (carbon dioxide gas) absorbs heat from the phase-change material through the coil to heat up, so as to realize the instant heating function. With the continuous heat absorption of the cold medium, the temperature of the phase-change material decreases, the phase-change material changes phase at the phase-change temperature point, and releases latent heat. The temperature of the phase-change material continues to decrease after the phase-change process and the phase-change end, and the heat release process is completed.

[0067] In some embodiments, the inlet end of the first compressor 33 is connected to the carbon dioxide outlet 21 of the desorption tower 2 through a first pipeline 61, and a first valve 62 is arranged on the first pipeline 61. The first valve 62 can control the opening and stop of the pipeline between the carbon dioxide and the first compressor 33. In response to the need for energy storage during the day, the first valve 62 is opened, the photovoltaic panel 32 generates electric energy to drive the first compressor 33 to work, and part of the carbon dioxide enters the first compressor 33 and is compressed into liquid carbon dioxide. In response to the need for energy storage, for example, at night, the first valve 62 is closed.

[0068] Further, the carbon capture system suitable for the rapid start-stop of the peak regulation unit further comprises a third storage tank 71. The inlet end of the third storage tank 71 is connected to the carbon dioxide outlet 21 of the desorption tower 2, and the outlet end of the third storage tank 71 is connected to the inlet end of the first compressor 33 and the inlet end of the carbon capture processing assembly.

[0069] It should be understood that the third storage tank 71 can be used as an intermediate storage tank of carbon dioxide. In response to the stop of the carbon capture system, in order to ensure the operation of the energy storage device 3, the carbon dioxide in the third storage tank 71 can be transported to the first compressor 33 for compression and energy storage. For example, when the peak regulation unit does not work during the day, the carbon capture system stops working, and there is no source of carbon dioxide, which will cause the electric energy generated by the photovoltaic panel 32 to be unable to drive the first compressor 33 to store energy. Due to the arrangement of the third storage tank 71, the carbon dioxide in the third storage tank 71 can be used to ensure the normal operation of the energy storage device 3.

[0070] In some embodiments, the carbon dioxide outlet 21 of the desorption tower 2 is connected to the inlet end of the carbon capture processing assembly through a second pipeline 63, and a second valve 64 is arranged on the second pipeline 63. According to the operation requirements of the system, it can be determined whether to open or close the second valve 64 on the second pipeline 63. For example, when the carbon dioxide generated by the carbon capture system needs to be supplied to the energy storage device 3, the second valve 64 is closed. In response to the non-working of the energy storage device 3 or the excess carbon dioxide needing to be processed, the second valve 64 is opened.

[0071] In some embodiments, the first storage tank 31 has a second outlet 312, and a second storage tank is connected to the second outlet 312. The second storage tank can be used as a secondary storage to increase the storage capacity.

[0072] In some embodiments, the carbon capture processing assembly comprises a second compressor 72. The second compressor 72 is used to compress and store the gaseous carbon dioxide, so as to facilitate subsequent application.

[0073] In some embodiments, the photovoltaic panel 32 is arranged on the top of the first storage tank 31. By arranging the photovoltaic panel 32 on the top of the first storage tank 31, the land occupation can be reduced, the integration of the equipment can be improved, and the layout of the plant can be optimized.

[0074] As shown in FIG. 1 and FIG. 2, the carbon capture system quick start-stop method according to the embodiments of the present disclosure is used for the quick start-stop operation of the carbon capture system suitable for the quick start-stop of the peak shaving unit in any of the above embodiments, and includes the following steps:

[0075] S101, the photovoltaic panel 32 receives sunlight and converts it into electrical energy.

[0076] S102, using the electrical energy provided by the photovoltaic panel 32, part of the gaseous carbon dioxide discharged by the thermal power unit is compressed into liquid carbon dioxide to achieve energy storage. It should be understood that after the carbon dioxide in the flue gas discharged by the thermal power unit is captured by the carbon capture system, part of the gaseous carbon dioxide is converted into liquid carbon dioxide by the compressor driven by the electrical energy generated by the photovoltaic panel 32.

[0077] In some embodiments, the heat generated during the conversion of carbon dioxide can also be stored by the heat storage assembly, realizing the decoupling conversion storage of electrical energy into internal energy and thermal energy of carbon dioxide.

[0078] S103, after the peak shaving unit is started, the liquid carbon dioxide is used to drive the turbine 34 to operate, and the generator 35 is driven to generate electricity to electrically heat the solutions in the absorption tower 1 and the desorption tower 2.

[0079] The carbon capture system also starts and stops with the peak shaving condition. Based on the increasing demand for electricity, after the peak shaving unit is started, the carbon capture system is also started synchronously. At this time, the liquid carbon dioxide is used to drive the turbine 34 to operate, and the generator 35 is driven to generate electricity to electrically heat the solutions in the absorption tower 1 and the desorption tower 2, realizing the rapid heating of the solutions in the absorption tower 1 and the desorption tower 2, shortening the start-up time of the carbon capture system, and improving the carbon capture effect.

[0080] In the gasification process of liquid carbon dioxide, the gasification expansion effect can be improved by heating the carbon dioxide, realizing the coupling conversion of the internal energy and the thermal energy of carbon dioxide into electrical energy.

[0081] S104, after the temperature of the solution in the absorption tower 1 reaches a first preset threshold value and the temperature of the solution in the desorption tower 2 reaches a second preset threshold value, the turbine 34 and the generator 35 are closed.

[0082] S105, the solution entering the desorption tower 2 is heated by the reboiler to maintain the temperature of the solutions in the absorption tower 1 and the desorption tower 2, realizing the quick start of the carbon capture system.

[0083] The system reaches a steady state operation by electric heating in a starting stage of the carbon capture system; in the daytime, photovoltaic power generation is coupled with compressed carbon dioxide energy storage; the carbon dioxide obtained by capture is used as an energy storage medium; and the carbon capture system provides electric energy required by electric heating in a starting preliminary stage of a peak regulation unit.

[0084] The embodiments of the present disclosure can store carbon dioxide energy while capturing carbon, reduce energy consumption of the carbon capture system, improve system balance, and help further development of the carbon capture system.

[0085] Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present disclosure, and those of ordinary skill in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A carbon capture system suitable for quick start-stop of a peak-shaving unit, comprising an absorption tower, a desorption tower, a heat exchanger connected between the absorption tower and the desorption tower for heat exchange of a first working medium entering the absorption tower from the desorption tower and a second working medium entering the desorption tower from the absorption tower, and a carbon capture treatment assembly connected with a carbon dioxide outlet of the desorption tower; the absorption tower has a first electric heating assembly for heating the first working medium in the absorption tower, and the desorption tower has a second electric heating assembly and a reboiler for heating the second working medium in the desorption tower.

2. The fast start-up and shutdown carbon capture system suitable for a peak shaving unit of claim 1, wherein, a plurality of the first electric heating assemblies are arranged in the inner cavity of the absorption tower along the height direction of the absorption tower; and / or a plurality of the second electric heating assemblies are arranged in the inner cavity of the desorption tower along the height direction of the desorption tower.

3. The fast start-up and shutdown carbon capture system suitable for a peak shaving unit of claim 2, wherein, The first electric heating assembly and the second electric heating assembly each comprise a temperature control component for controlling the temperature of the corresponding electric heating assembly.

4. The fast start-up and shutdown carbon capture system suitable for a peak shaving unit of claim 2, wherein, The first electric heating assembly and the second electric heating assembly each comprise a plurality of electric heating wires arranged in a grid shape.

5. The fast start-stop carbon capture system suitable for a peak-shaving plant of any one of claims 1 to 4, wherein, The temperature in the absorption tower is 40-50°C, and the temperature in the desorption tower is 110-120°C.

6. The fast start-stop carbon capture system suitable for a peak-shaving plant of any one of claims 1 to 5, wherein, Further comprising a photovoltaic panel and an energy storage device, the photovoltaic panel being connected with the energy storage device, and the energy storage device being connected with the first electric heating assembly and the second electric heating assembly.

7. The fast start-up and shutdown carbon capture system suitable for peaking plant of claim 6, wherein, The energy storage device comprises: a first storage tank having a first inlet and a first outlet; a first compressor having an inlet end connected with the carbon dioxide outlet of the desorption tower, an outlet end connected with the first inlet, and a driving portion connected with the photovoltaic panel; a power generation component connected with the first outlet of the first storage tank and connected with the first electric heating assembly and the second electric heating assembly to supply power to the first electric heating assembly and the second electric heating assembly.

8. The fast start-up and shutdown carbon capture system suitable for peaking plant of claim 7, wherein, The inlet end of the first compressor and the carbon dioxide outlet of the desorption tower are connected through a first pipeline, and a first valve is arranged on the first pipeline; and / or the carbon dioxide outlet of the desorption tower and the inlet end of the carbon capture treatment assembly are connected through a second pipeline, and a second valve is arranged on the second pipeline; and / or the power generation component comprises a turbine and a generator, the inlet end of the turbine is connected with the first outlet of the first storage tank, the outlet end of the turbine is connected with the inlet end of the carbon capture treatment assembly, and the turbine is drivingly connected with the generator to drive the generator to work; and / or the first storage tank has a second outlet connected with a second storage tank.

9. The fast start-up and shutdown carbon capture system adapted for a peak shaving unit of claim 7, wherein, a third storage tank, an inlet end of the third storage tank being connected with a carbon dioxide outlet of the desorption tower, an outlet end of the third storage tank being connected with an inlet end of the first compressor and an inlet end of the carbon capture processing assembly; and / or the carbon capture processing assembly comprises a second compressor; and / or the photovoltaic panel is arranged on a top of the first storage tank; and / or a heat storage assembly is further included, the heat storage assembly being used for storing heat released when the first compressor compresses carbon dioxide, and the heat storage assembly being used for heating carbon dioxide discharged from a first outlet of the first storage tank. 10.A method for quick start and stop of a carbon capture system, the method being used for quick start and stop of the carbon capture system adapted for quick start and stop of a peak-shaving unit according to any one of claims 1 to 9, and the method comprising the following steps: the photovoltaic panel receives sunlight and converts the sunlight into electric energy; the electric energy provided by the photovoltaic panel is used to compress part of gaseous carbon dioxide discharged from the thermal power unit into liquid carbon dioxide to achieve energy storage; after the peak-shaving unit is started, the liquid carbon dioxide is used to drive a turbine to operate and drive a generator to generate electricity to electrically heat solutions in the absorption tower and the desorption tower; after a temperature of the solution in the absorption tower reaches a first preset threshold value and a temperature of the solution in the desorption tower reaches a second preset threshold value, the turbine and the generator are stopped; the reboiler is used to heat the solution entering the desorption tower to maintain the temperatures of the solutions in the absorption tower and the desorption tower, and to achieve quick start of the carbon capture system.

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