Solar-assisted carbon capture coal-fired power generation device and method

Abstract

The invention belongs to the technical field of coal-fired power generation, and particularly relates to a solar-assisted carbon capture coal-fired power generation device and method. The device comprises a boiler, a steam turbine, a carbon capture system, a fused salt heat storage tank, a recoverer, an oil-water heat exchanger, a recoverer and a steam-water separator, a tail flue outlet of the boiler is connected with an inlet of the carbon capture system; a steam outlet of the boiler is connected with an inlet of the steam turbine; a steam exhaust port of the steam turbine is connected with a heat release side inlet of the fused salt heat storage tank, a heat absorption side outlet of the fused salt heat storage tank is connected with a steam inlet of the carbon capture system, a steam outlet of the carbon capture system is communicated with a heat absorption side inlet of the fused salt heat storage tank, and a heat release side outlet of the fused salt heat storage tank is communicated with an inlet of the recoverer. And an outlet of the recoverer is connected with the steam-water separator through the water side of the oil-water heat exchanger. According to the device, the environmental protection performance and economical efficiency of the solar-assisted carbon capture coal-fired power generation system can be remarkably improved, and the device is expected to become one of important solutions for carbon emission reduction in the coal power industry in the future.

Description

Technical Field

[0001] This invention belongs to the field of coal-fired power generation technology, specifically relating to a solar-assisted carbon capture coal-fired power generation device and method. Background Technology

[0002] With the increasing severity of global warming, reducing carbon dioxide emissions has become a major challenge facing the world. There is an urgent need to develop efficient and economical carbon reduction technologies. Combining carbon capture with coal-fired power generation is a promising solution, but traditional carbon capture processes are energy-intensive, severely impacting power generation efficiency. Significant progress has been made in solar thermal power generation technology, providing a new approach to solving the energy consumption problem of carbon capture. Combining solar thermal power generation with coal-fired power generation and carbon capture to form a solar-assisted carbon capture coal-fired power generation system is expected to significantly reduce carbon capture energy consumption and improve power generation efficiency. However, the intermittent and seasonal variations of solar energy resources pose significant challenges to system operation and control. Therefore, there is an urgent need to develop advanced control strategies suitable for this system. Summary of the Invention

[0003] This application provides a solar-assisted carbon capture coal-fired power generation device and method, aiming to solve the problem of complex control of solar thermal power generation caused by the intermittent and seasonal changes of solar energy resources.

[0004] The first aspect of this application provides a solar-assisted carbon capture coal-fired power generation device, including a boiler, a steam turbine, a carbon capture system, a molten salt thermal storage tank, a recovery unit, an oil-water heat exchanger, a recovery unit, and a steam-water separator;

[0005] The boiler's tail flue outlet is connected to the inlet of the carbon capture system, and the boiler's steam outlet is connected to the inlet of the steam turbine. The steam turbine's exhaust port is connected to the heat release side inlet of the molten salt thermal storage tank. The molten salt thermal storage tank's heat absorption side outlet is connected to the steam inlet of the carbon capture system. The carbon capture system's steam outlet is connected to the heat absorption side inlet of the molten salt thermal storage tank. The molten salt thermal storage tank's heat release side outlet is connected to the inlet of the recovery unit. The recovery unit's outlet is connected to the steam-water separator via the water side of the oil-water heat exchanger.

[0006] According to some embodiments of the solar-assisted carbon capture coal-fired power generation device described in this application, it also includes a solar collector, wherein the steam outlet of the steam-water separator is connected to the heat release side inlet of the molten salt heat storage tank, the water outlet of the steam-water separator is connected to the inlet of the recovery unit, and the solar collector is connected to the oil side of the oil-water heat exchanger.

[0007] According to some embodiments of the solar-assisted carbon capture coal-fired power generation device described in this application, it also includes a condenser and a regenerative heater system. The exhaust port of the steam turbine is connected to the inlet of the condenser, the outlet of the condenser is connected to the inlet of the boiler via the heat absorption side of the regenerative heater system, and the extraction port of the steam turbine is connected to the heat release side of the regenerative heater system.

[0008] According to some embodiments of the solar-assisted carbon capture coal-fired power generation device described in this application, an air preheater is also included, wherein the boiler tail flue outlet is connected to the inlet of the carbon capture system via the air preheater.

[0009] According to some embodiments of the solar-assisted carbon capture coal-fired power generation device described in this application, the outlet of the solar collector is connected to the oil-side inlet of an oil-water heat exchanger via a pump, and the oil-side outlet of the oil-water heat exchanger is connected to the inlet of the solar collector.

[0010] According to some embodiments of the solar-assisted carbon capture coal-fired power generation device described in this application, it further includes a first valve, a second valve, and a third valve. The first valve is installed on the pipeline connecting the exhaust port of the steam turbine and the molten salt thermal storage tank; the second valve is installed on the pipeline connecting the steam outlet of the steam-water separator and the heat release side inlet of the molten salt thermal storage tank; and the third valve is installed on the pipeline connecting the heat absorption side outlet of the molten salt thermal storage tank and the steam inlet of the carbon capture system.

[0011] According to some embodiments of the solar-assisted carbon capture coal-fired power generation device described in this application, it also includes a controller, which is connected to the control terminals of the first valve, the second valve, and the third valve.

[0012] The second aspect of this application provides a method for solar-assisted carbon capture coal-fired power generation, implemented based on the solar-assisted carbon capture coal-fired power generation device described in the first aspect of this application.

[0013] According to some embodiments of the solar-assisted carbon capture coal-fired power generation method described in this application, when the grid load increases, the second valve is controlled to increase its opening, the third valve is controlled to increase its opening, and the first valve is controlled to decrease its opening; when the grid load decreases, the first valve is controlled to increase its opening, the second valve is controlled to decrease its opening, and the third valve is controlled to decrease its opening.

[0014] The beneficial effects of this application include: the introduction of a molten salt thermal storage tank into the solar-assisted carbon capture (CACC) coal-fired power generation device described in this application allows for the storage of excess heat when solar resources are abundant and the release of heat when solar energy is insufficient, thereby achieving peak shaving and valley filling on the source side and mitigating the impact of renewable energy fluctuations. Simultaneously, it optimizes the coupling method between the carbon capture device and the power generation system and formulates a multi-variable collaborative control strategy for factors such as solar output and load demand. This achieves source-grid-load coordination in aspects such as turbine start-up and shutdown, power generation load regulation, and regeneration steam extraction pressure optimization, maximizing solar energy utilization efficiency and ensuring unit flexibility and carbon capture rate. This application can significantly improve the environmental performance and economic efficiency of solar-assisted CACC coal-fired power generation systems and is expected to become one of the important solutions for carbon emission reduction in the coal-fired power industry in the future. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the solar-assisted carbon capture coal-fired power generation device described in this application.

[0016] In the diagram: 1. Boiler, 2. Air preheater, 3. Steam turbine, 4. Regenerative heater system, 5. Carbon capture system, 6. Condenser, 7. Third valve, 8. First valve, 9. Molten salt heat storage tank, 10. Second valve, 11. Pump, 12. Steam-water separator, 13. Heat collector, 14. Oil-water heat exchanger, 15. Recovery unit. Detailed Implementation

[0017] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0018] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0019] This application provides a solar-assisted carbon capture coal-fired power generation device, including a boiler, a steam turbine, a carbon capture system, a molten salt thermal storage tank, a recovery unit, an oil-water heat exchanger, a recovery unit, and a steam-water separator; The boiler's tail flue outlet is connected to the inlet of the carbon capture system, and the boiler's steam outlet is connected to the inlet of the steam turbine. The steam turbine's exhaust port is connected to the heat release side inlet of the molten salt thermal storage tank. The molten salt thermal storage tank's heat absorption side outlet is connected to the steam inlet of the carbon capture system. The carbon capture system's steam outlet is connected to the heat absorption side inlet of the molten salt thermal storage tank. The molten salt thermal storage tank's heat release side outlet is connected to the inlet of the recovery unit. The recovery unit's outlet is connected to the steam-water separator via the water side of the oil-water heat exchanger.

[0020] The solar-assisted carbon capture (CACC) coal-fired power generation device described in this application incorporates a molten salt thermal storage tank. This tank can store excess heat when solar resources are abundant and release heat when solar energy is insufficient, thereby achieving peak shaving and valley filling on the source side and mitigating the impact of renewable energy fluctuations. Simultaneously, the coupling method between the carbon capture device and the power generation system is optimized, and a multi-variable collaborative control strategy is formulated based on factors such as solar output and load demand. This achieves source-grid-load coordination in aspects such as turbine start-up and shutdown, power generation load regulation, and regeneration steam extraction pressure optimization, maximizing solar energy utilization efficiency and ensuring unit flexibility and carbon capture rate. This application can significantly improve the environmental performance and economic efficiency of solar-assisted CACC coal-fired power generation systems and is expected to become one of the important solutions for carbon emission reduction in the coal-fired power industry in the future.

[0021] In some embodiments of this application, a solar collector is also included, wherein the steam outlet of the steam-water separator is connected to the heat release side inlet of the molten salt heat storage tank, the water outlet of the steam-water separator is connected to the inlet of the recovery unit, and the solar collector is connected to the oil side of the oil-water heat exchanger.

[0022] In some embodiments of this application, a condenser and a regenerative heater system are also included, wherein the exhaust port of the steam turbine is connected to the inlet of the condenser, the outlet of the condenser is connected to the inlet of the boiler via the heat absorption side of the regenerative heater system, and the extraction port of the steam turbine is connected to the heat release side of the regenerative heater system.

[0023] In some embodiments of this application, an air preheater is also included, and the boiler tail flue outlet is connected to the inlet of the carbon capture system via the air preheater.

[0024] In some embodiments of this application, the outlet of the solar collector is connected to the oil-side inlet of an oil-water heat exchanger via a pump, and the oil-side outlet of the oil-water heat exchanger is connected to the inlet of the solar collector.

[0025] In some embodiments of this application, a first valve, a second valve, and a third valve are also provided. The first valve is provided on the pipe connecting the exhaust port of the steam turbine and the molten salt thermal storage tank; the second valve is provided on the pipe connecting the steam outlet of the steam-water separator and the heat release side inlet of the molten salt thermal storage tank; and the third valve is provided on the pipe connecting the heat absorption side outlet of the molten salt thermal storage tank and the steam inlet of the carbon capture system.

[0026] In some embodiments of this application, a controller is also included, which is connected to the control terminals of the first valve, the second valve, and the third valve.

[0027] This application also provides a method for solar-assisted carbon capture coal-fired power generation, implemented based on the solar-assisted carbon capture coal-fired power generation device described in the first aspect of this application.

[0028] In some embodiments of this application, when the grid load increases, the second valve is controlled to increase its opening, the third valve is controlled to increase its opening, and the first valve is controlled to decrease its opening; when the grid load decreases, the first valve is controlled to increase its opening, the second valve is controlled to decrease its opening, and the third valve is controlled to decrease its opening.

[0029] The technical solution of this application will be further described below with reference to specific embodiments.

[0030] Example 1 refer to Figure 1 The solar-assisted carbon capture coal-fired power generation device described in this application includes a boiler 1, an air preheater 2, a steam turbine 3, a regenerative heater system 4, a carbon capture system 5, a condenser 6, a third valve 7, a first valve 8, a molten salt heat storage tank 9, a second valve 10, a pump 11, a steam-water separator 12, a solar collector 13, an oil-water heat exchanger 14, and a recovery unit 15. The steam outlet of boiler 1 is connected to the inlet of turbine 3, and the exhaust port of turbine 3 is connected to the inlet of condenser 6. The outlet of condenser 6 is connected to the inlet of boiler 1 via the heat absorption side of regenerative heater system 4. The extraction port of turbine 3 is connected to the heat release side of regenerative heater system 4. The exhaust port of turbine 3 is connected to the heat release side inlet and heat absorption side inlet of molten salt thermal storage tank 9 via first valve 8. The tail flue of boiler 1 is connected to the inlet of carbon capture system 5 via air preheater 2. The heat absorption side outlet of molten salt thermal storage tank 9 is connected to the steam inlet of carbon capture system 5 via third valve 7. The steam outlet of the collector system 5 is connected to the heat absorption side inlet of the molten salt heat storage tank 9. The heat release side outlet of the molten salt heat storage tank 9 is connected to the inlet of the recovery unit 15. The outlet of the recovery unit 15 is connected to the inlet of the steam-water separator 12 via the water side of the oil-water heat exchanger 14. The steam outlet of the steam-water separator 12 is connected to the heat release side inlet of the molten salt heat storage tank 9 via the second valve 10. The water outlet of the steam-water separator 12 is connected to the inlet of the recovery unit 15. The outlet of the collector 13 is connected to the oil side inlet of the oil-water heat exchanger 14 via the pump 11. The oil side outlet of the oil-water heat exchanger 14 is connected to the inlet of the collector 13.

[0031] It should be noted that the present invention involves a first valve 8, a second valve 10 and a third valve 7, wherein the first valve 8 is used to control the steam volume of the unit, the second valve 10 is used to adjust the steam volume output by the steam-water separator 12, and the third valve 7 is used to control the hot water volume.

[0032] The working process of the solar-assisted carbon capture coal-fired power generation device described in this application is as follows: Steam output from boiler 1 enters steam turbine 3. The exhaust steam from steam turbine 3 is divided into two paths. One path enters boiler 1 through condenser 6 and regenerative heater system 4. The other path enters the heat absorption and heat release sides of molten salt heat storage tank 9 through first valve 8. The heat transfer oil output from collector 13 enters oil-water heat exchanger 14 to release heat and then returns to collector 13. The feedwater output from the recovery unit 15 enters the oil-water heat exchanger 14 to absorb heat, and then enters the steam-water separator 12 for separation. The separated water enters the recovery unit 15, and the separated steam enters the heat release side of the molten salt heat storage tank 9 through the second valve 10 to release heat, and then returns to the recovery unit 15. The steam output from the heat absorption side of the molten salt heat storage tank 9 enters the carbon capture system 5 through the third valve 7 to release heat, and then returns to the heat absorption side of the molten salt heat storage tank 9.

[0033] Example 2 A method for solar-assisted carbon capture (CACC) power generation, wherein the method is implemented based on the CACC power generation device described in Example 1, the CACC power generation device comprising a boiler 1, an air preheater 2, a steam turbine 3, a regenerative heater system 4, a carbon capture system 5, a condenser 6, a third valve 7, a first valve 8, a molten salt thermal storage tank 9, a second valve 10, a pump 11, a steam-water separator 12, a solar collector 13, an oil-water heat exchanger 14, and a recovery unit 15; Specifically, the method for solar-assisted carbon capture in coal-fired power generation includes the following steps: When the grid load increases, the coal-fired power generation system needs to increase the output of its units to meet the grid's demands. At this time, the second valve 10 is controlled to increase its opening, the third valve 7 is controlled to increase its opening, and the first valve 8 is controlled to decrease its opening. When the grid load decreases, the coal-fired power generation system needs to reduce the output of its units. Therefore, the first valve 8 is controlled to increase its opening, the second valve 10 is controlled to decrease its opening, and the third valve 7 is controlled to decrease its opening.

[0034] It should be noted that the present invention has the following characteristics: This invention combines thermal storage trough solar thermal power generation with coal-fired power generation and carbon capture to form a novel integrated system. It also introduces molten salt thermal storage, which can store excess heat when solar resources are abundant and release heat when solar energy is insufficient, thereby achieving peak shaving and valley filling on the source side, mitigating the impact of renewable energy fluctuations, and improving solar energy utilization efficiency.

[0035] This application proposes a multi-variable coordinated control strategy for the variable operating conditions of the power plant. Through the coordinated adjustment of three valves, the coal-fired power generation system can achieve rapid response to grid load fluctuations. When the load increases, the opening of the second valve 10 and the third valve 7 is increased, while the opening of the first valve 8 is decreased; when the load decreases, the opening of the first valve 8 is increased, while the openings of the second valve 10 and the third valve 7 are decreased. This flexible control strategy improves the system's operational flexibility.

[0036] This application optimizes the coupling method between the carbon capture device and the power generation system, utilizing solar energy and molten salt thermal storage to heat the carbon capture system 5. This significantly reduces the impact of carbon capture on the coal-fired power generation system and decreases coal consumption. Simultaneously, the emission of flue gas after carbon capture treatment significantly reduces carbon dioxide emissions.

[0037] Example 3 A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of a solar-assisted carbon capture and power generation method, for example, including: when the grid load increases, controlling a second valve 10 to increase its opening, controlling a third valve 7 to increase its opening, and controlling a first valve 8 to decrease its opening; when the grid load decreases, controlling the first valve 8 to increase its opening, controlling the second valve 10 to decrease its opening, and controlling the third valve 7 to decrease its opening. The memory includes main memory, such as high-speed random access memory, and also includes non-volatile memory, such as at least one disk storage device. The processor, network interface, and memory are interconnected via an internal bus, which can be an industry-standard architecture bus, a peripheral component interconnection standard bus, an extended industry-standard architecture bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The memory stores the program; specifically, the program can include program code, which includes computer operation instructions. The memory can include main memory and non-volatile memory, and provides instructions and data to the processor.

[0038] Example 4 A computer-readable storage medium storing a computer program, which, when executed by a processor, implements a method for solar-assisted carbon capture and coal-fired power generation, comprising: when the grid load increases, controlling a second valve 10 to increase its opening, controlling a third valve 7 to increase its opening, and controlling a first valve 8 to decrease its opening; when the grid load decreases, controlling the first valve 8 to increase its opening, controlling the second valve 10 to decrease its opening, and controlling the third valve 7 to decrease its opening. Specifically, the computer-readable storage medium includes, but is not limited to, volatile memory and / or non-volatile memory. The volatile memory may include random access memory (RAM) and / or cache memory, etc. The non-volatile memory may include read-only memory (ROM), hard disk, flash memory, optical disk, magnetic disk, etc.

[0039] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0040] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0041] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0042] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0043] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and disclosure of the invention. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims.

[0044] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

[0045] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A solar-assisted carbon capture coal-fired power generation device, characterized in that, It includes a boiler (1), a steam turbine (3), a carbon capture system (5), a molten salt heat storage tank (9), a recovery unit (15), an oil-water heat exchanger (14), a recovery unit (15), and a steam-water separator (12). The tail flue outlet of the boiler (1) is connected to the inlet of the carbon capture system (5), and the steam outlet of the boiler (1) is connected to the inlet of the steam turbine (3); the exhaust port of the steam turbine (3) is connected to the heat release side inlet of the molten salt heat storage tank (9), the heat absorption outlet of the molten salt heat storage tank (9) is connected to the steam inlet of the carbon capture system (5), the steam outlet of the carbon capture system (5) is connected to the heat absorption side inlet of the molten salt heat storage tank (9), the heat release side outlet of the molten salt heat storage tank (9) is connected to the inlet of the recovery unit (15), and the outlet of the recovery unit (15) is connected to the steam-water separator (12) via the water side of the oil-water heat exchanger (14).

2. The solar-assisted carbon capture coal-fired power generation device according to claim 1, characterized in that, It also includes a solar collector (13), the steam outlet of the steam-water separator (12) is connected to the heat release side inlet of the molten salt heat storage tank (9), the water outlet of the steam-water separator (12) is connected to the inlet of the recovery unit (15), and the solar collector (13) is connected to the oil side of the oil-water heat exchanger (14).

3. The solar-assisted carbon capture coal-fired power generation device according to claim 1, characterized in that, It also includes a condenser (6) and a regenerative heater system (4). The exhaust port of the turbine (3) is connected to the inlet of the condenser (6). The outlet of the condenser (6) is connected to the inlet of the boiler (1) via the heat absorption side of the regenerative heater system (4). The extraction port of the turbine (3) is connected to the heat release side of the regenerative heater system (4).

4. The solar-assisted carbon capture coal-fired power generation device according to claim 1, characterized in that, It also includes an air preheater (2), and the tail flue outlet of the boiler (1) is connected to the inlet of the carbon capture system (5) via the air preheater (2).

5. The solar-assisted carbon capture coal-fired power generation device according to claim 2, characterized in that, The outlet of the solar collector (13) is connected to the oil-side inlet of the oil-water heat exchanger (14) via a pump (11), and the oil-side outlet of the oil-water heat exchanger (14) is connected to the inlet of the solar collector (13).

6. The solar-assisted carbon capture coal-fired power generation device according to claim 1, characterized in that, It also includes a first valve (8), a second valve (10) and a third valve (7). The first valve (8) is installed on the pipe connecting the exhaust port of the steam turbine (3) and the molten salt heat storage tank (9); the second valve (10) is installed on the pipe connecting the steam outlet of the steam-water separator (12) and the heat release side inlet of the molten salt heat storage tank (9); and the third valve (7) is installed on the pipe connecting the heat absorption side outlet of the molten salt heat storage tank (9) and the steam inlet of the carbon capture system (5).

7. The solar-assisted carbon capture coal-fired power generation device according to claim 6, characterized in that, It also includes a controller, which is connected to the control end of the first valve (8), the control end of the second valve (10) and the control end of the third valve (7).

8. A method for solar-assisted carbon capture in coal-fired power generation, characterized in that, The implementation is based on the solar-assisted carbon capture coal-fired power generation device according to any one of claims 1-7.

9. The method for solar-assisted carbon capture and coal-fired power generation according to claim 8, characterized in that, When the grid load increases, control the second valve (10) to increase its opening, control the third valve (7) to increase its opening, and control the first valve (8) to decrease its opening; when the grid load decreases, control the first valve (8) to increase its opening, control the second valve (10) to decrease its opening, and control the third valve (7) to decrease its opening.

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