Coal-fired power generation system integrated with heat pump heat storage cycle and operation method thereof

Abstract

The application discloses a coal-fired power generation system integrated with a heat pump heat storage cycle and an operation method, and belongs to the technical field of coal-fired power generation. The coal-fired power generation system integrated with the heat pump heat storage cycle is coupled with a heat pump heat storage and heat release system, and under the control of heat storage valves and heat release valves, heat energy of low-temperature flue gas can be stored when the load of a power grid is low, heat loss of the coal-fired system is reduced, heat storage energy of a high-temperature heat storage tank can be quickly released when the load of the power grid is high, the power generation capacity of the coal-fired power generation system is increased, and the load change demand can be quickly responded to through flexible switching of heat storage operation and heat release operation modes, so that the peak regulation capacity of the power grid is improved.

Description

Technical Field

[0001] This invention relates to the field of coal-fired power generation technology, specifically to a coal-fired power generation system and operation method with integrated heat pump thermal storage cycle. Background Technology

[0002] Coal-fired power generation, historically the dominant method of electricity production, presents inherent operational characteristics and environmental pressures that are particularly prominent in the context of the current energy transition. Supercritical water gasification technology for coal-fired power utilizes supercritical water as a medium to efficiently convert coal into hydrogen-rich syngas under extremely high temperatures and pressures. This not only improves hydrogen production efficiency but also facilitates the deposition and separation of harmful elements such as nitrogen and sulfur through a specific chemical reaction pathway, simplifying subsequent pollution control. More importantly, this technology also facilitates carbon capture during coal combustion, contributing to the reduction of greenhouse gas emissions and aligning with the global trend towards low-carbon energy transition.

[0003] Despite the significant potential of supercritical water gasification technology for coal-fired power plants in improving energy conversion efficiency and environmental friendliness, it still faces several challenges in practical applications. In particular, its ability to rapidly respond to changes in grid load is relatively limited, especially during peak-shaving operations, where its lack of flexibility is particularly pronounced. This not only restricts its adaptability to modern power grids but also exacerbates the operational difficulties of power systems facing the intermittency and uncertainty of renewable energy sources.

[0004] Therefore, how to achieve flexibility in coal-fired power generation systems has become a technical challenge that urgently needs to be overcome by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a coal-fired power generation system and operation method with integrated heat pump thermal storage cycle, so as to overcome the problem of insufficient flexibility of coal-fired power generation system during peak shaving operation in the prior art.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution:

[0007] This invention provides a coal-fired power generation system with an integrated heat pump thermal storage cycle, including a heat pump thermal storage system, a heat release system, and a coal supercritical water gasification power generation system; the heat pump thermal storage system includes thermal storage valves, a heat pump evaporator, a heat pump compressor, a thermal storage heat exchanger, a heat pump expansion valve, a low-temperature thermal storage tank, and a high-temperature thermal storage tank; the heat release system includes a low-temperature thermal storage tank, a high-temperature thermal storage tank, a heat release valve, and a heat release heat exchanger;

[0008] The low-temperature flue gas from the supercritical coal gasification power generation system is connected to the cooling inlet of the supercritical coal gasification power generation system via a heat storage valve and the hot end of the heat pump evaporator. The cold end outlet of the heat pump evaporator is connected to the heat pump compressor, the hot end of the heat storage heat exchanger, and the heat pump expansion valve to the cold end inlet of the heat pump evaporator. The outlet of the low-temperature heat storage tank is connected to the inlet of the high-temperature heat storage tank via the cold end of the heat storage heat exchanger.

[0009] The pressurized gasification feedwater of the supercritical water gasification power generation system is connected to the oxidation reaction inlet of the supercritical water gasification power generation system via a heat release valve and the cold end of a heat release heat exchanger. The outlet of the high-temperature heat storage tank is connected to the low-temperature heat storage tank via the hot end of a heat release heat exchanger.

[0010] A further improvement of the present invention is that the coal supercritical water gasification power generation system includes a supercritical water gasification reactor, a burner, a gas turbine, a feedwater heat exchanger, a cooler, a gas-liquid separator, a feedwater pump, and an organic Rankine cycle system.

[0011] The supercritical water gasification reactor is sequentially connected to a burner, a gas turbine, the hot end of a feedwater heat exchanger, the hot end of an organic Rankine cycle system, a cooler, a gas-liquid separator, and a feedwater pump to the cold end of the feedwater heat exchanger. The cold end outlet of the feedwater heat exchanger is connected to the inlet of the supercritical water gasification reactor and the burner, respectively.

[0012] A further improvement of the present invention is that the organic Rankine cycle system includes an organic working fluid heat exchanger, an organic working fluid turbine, a condenser, and an organic working fluid pump, wherein the cold end outlet of the organic working fluid heat exchanger is sequentially connected to the organic working fluid turbine, the condenser, and the organic working fluid pump to the cold end inlet of the organic working fluid heat exchanger, and the hot end of the organic working fluid heat exchanger is the hot end of the organic Rankine cycle system.

[0013] A further improvement of the present invention is that the inlet temperature of the gas turbine is 700℃~1500℃.

[0014] A further improvement of the present invention is that the outlet temperature of the cooler is 20℃~35℃.

[0015] A further improvement of this invention is that the operating temperature of the supercritical water gasification reactor is 600℃~700℃.

[0016] A further improvement of this invention is that the operating pressure of the supercritical water gasification reactor is 25 MPa to 30 MPa.

[0017] A further improvement of the present invention is that the heat storage medium of the heat pump heat storage system and the heat release system is molten salt.

[0018] This invention also provides an operation method for a coal-fired power generation system with an integrated heat pump thermal storage cycle. The coal-fired power generation system with the integrated heat pump thermal storage cycle described above is operated by opening the thermal storage valve and closing the heat release valve. The coal-fired power generation system is in the thermal pump thermal storage operation mode. The low-temperature flue gas from the coal supercritical water gasification power generation system enters the hot end inlet of the heat pump evaporator through the thermal storage valve. The cold end outlet of the heat pump evaporator is pressurized by the heat pump compressor and then enters the hot end inlet of the thermal storage heat exchanger. The hot end outlet of the thermal storage heat exchanger is depressurized by the heat pump expansion valve and then enters the cold end inlet of the heat pump evaporator. The thermal storage medium at the outlet of the low-temperature thermal storage tank is heated by the cold end of the thermal storage heat exchanger and then enters the high-temperature thermal storage tank.

[0019] With the heat release valve open and the heat storage valve closed, the coal-fired power generation system is in heat release operation mode. The pressurized gasification feedwater of the coal supercritical water gasification power generation system enters the oxidation reaction inlet of the coal supercritical water gasification power generation system sequentially through the heat release valve and the cold end of the heat release heat exchanger. The heat storage medium at the outlet of the high-temperature heat storage tank enters the low-temperature heat storage tank after releasing heat at the hot end of the heat release heat exchanger.

[0020] A further improvement of this invention is that: when the coal-fired power generation system is in heat pump thermal storage operation mode, the power generation of the coal supercritical water gasification power generation system is reduced by recovering the low-temperature thermal energy of the low-temperature flue gas, and the low-temperature thermal energy is converted into high-temperature thermal energy and stored in the high-temperature thermal storage tank; when the coal-fired power generation system is in heat release operation mode, the power generation of the coal supercritical water gasification power generation system is increased by releasing the thermal energy stored in the high-temperature thermal storage tank to the pressurized gasification feedwater.

[0021] Compared with the prior art, the positive and progressive effects of the present invention are as follows:

[0022] The coal-fired power generation system with integrated heat pump thermal storage cycle provided by this invention, by coupling heat pump thermal storage and heat release systems, and under the control of thermal storage valves and heat release valves, realizes the storage of thermal energy of low-temperature flue gas during the off-peak of grid load, reducing the heat loss of the coal-fired system. During the peak of load, it increases the power generation of the coal-fired power generation system by rapidly releasing the thermal energy stored in the high-temperature thermal storage tank. Through the flexible switching between thermal storage operation and heat release operation modes, it can quickly respond to load change demands and improve the grid peak-shaving capability. Attached Figure Description

[0023] The accompanying drawings are provided to further understand the invention and constitute a part of this invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] Figure 1 This is a connection diagram of a coal-fired power generation system with an integrated heat pump thermal storage cycle according to the present invention.

[0025] Figure 2 A connection diagram for the heat pump thermal storage operation mode;

[0026] Figure 3 This is a connection diagram for the exothermic operation mode;

[0027] 1 is a supercritical water gasification reactor, 2 is a burner, 3 is a gas turbine, 4 is a feedwater heat exchanger, 5 is an organic working fluid heat exchanger, 6 is a cooler, 7 is a gas-liquid separator, 8 is a feedwater pump, 9 is an organic working fluid turbine, 10 is a condenser, 11 is an organic working fluid pump, 12 is a heat storage valve, 13 is a heat pump evaporator, 14 is a heat pump compressor, 15 is a heat storage heat exchanger, 16 is a heat pump expansion valve, 17 is a low-temperature heat storage tank, 18 is a high-temperature heat storage tank, 19 is a heat release valve, and 20 is a heat release heat exchanger. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. This is an explanation of the present invention and not a limitation thereof.

[0034] See Figure 1 A coal-fired power generation system integrating a heat pump thermal storage cycle includes a heat pump thermal storage system, a heat release system, and a coal supercritical water gasification power generation system; the heat pump thermal storage system includes a thermal storage valve 12, a heat pump evaporator 13, a heat pump compressor 14, a thermal storage heat exchanger 15, a heat pump expansion valve 16, a low-temperature thermal storage tank 17, and a high-temperature thermal storage tank 18; the heat release system includes a low-temperature thermal storage tank 17, a high-temperature thermal storage tank 18, a heat release valve 19, and a heat release heat exchanger 20;

[0035] The low-temperature flue gas of the supercritical coal gasification power generation system is connected to the cooling inlet of the supercritical coal gasification power generation system via the heat storage valve 12 and the hot end of the heat pump evaporator 13 in sequence; the cold end outlet of the heat pump evaporator 13 is connected to the heat pump compressor 14, the hot end of the heat storage heat exchanger 15, and the heat pump expansion valve 16 in sequence to the cold end inlet of the heat pump evaporator 13; the outlet of the low-temperature heat storage tank 17 is connected to the inlet of the high-temperature heat storage tank 18 via the cold end of the heat storage heat exchanger 15.

[0036] The pressurized gasification feedwater of the supercritical water gasification power generation system is connected to the oxidation reaction inlet of the supercritical water gasification power generation system via heat release valve 19 and the cold end of heat release heat exchanger 20. The outlet of the high temperature heat storage tank 18 is connected to the low temperature heat storage tank 17 via the hot end of heat release heat exchanger 20.

[0037] Specifically, the supercritical water gasification power generation system includes a supercritical water gasification reactor 1, a burner 2, a gas turbine 3, a feedwater heat exchanger 4, a cooler 6, a gas-liquid separator 7, a feedwater pump 8, and an organic Rankine cycle system.

[0038] The supercritical water gasification reactor 1 is sequentially connected to the burner 2, the gas turbine 3, the hot end of the feedwater heat exchanger 4, the hot end of the organic Rankine cycle system, the cooler 6, the gas-liquid separator 7, and the feedwater pump 8 to the cold end of the feedwater heat exchanger 4. The cold end outlet of the feedwater heat exchanger 4 is connected to the inlet of the supercritical water gasification reactor 1 and the burner 2, respectively.

[0039] Specifically, the organic Rankine cycle system includes an organic working fluid heat exchanger 5, an organic working fluid turbine 9, a condenser 10, and an organic working fluid pump 11. The cold end outlet of the organic working fluid heat exchanger 5 is sequentially connected to the organic working fluid turbine 9, the condenser 10, and the organic working fluid pump 11 to the cold end inlet of the organic working fluid heat exchanger 5. The hot end of the organic working fluid heat exchanger 5 is the hot end of the organic Rankine cycle system.

[0040] Specifically, the inlet temperature of gas turbine 3 is 700℃~1500℃.

[0041] Specifically, the outlet temperature of cooler 6 is 20℃~35℃.

[0042] Specifically, the operating temperature of the supercritical water gasification reactor 1 is 600℃~700℃.

[0043] Specifically, the operating pressure of the supercritical water gasification reactor 1 is 25 MPa to 30 MPa.

[0044] Specifically, molten salt is used as the heat storage medium in both the heat pump heat storage system and the heat release system.

[0045] Based on the same inventive concept, this invention provides an operation method for a coal-fired power generation system with an integrated heat pump thermal storage cycle, employing the coal-fired power generation system with the integrated heat pump thermal storage cycle described above. (See also...) Figure 2 Open the heat storage valve 12 and close the heat release valve 19. The coal-fired power generation system is in heat pump heat storage operation mode. The low temperature flue gas of the coal supercritical water gasification power generation system enters the hot end inlet of the heat pump evaporator 13 through the heat storage valve 12. The cold end outlet of the heat pump evaporator 13 is pressurized by the heat pump compressor 14 and enters the hot end inlet of the heat storage heat exchanger 15. The hot end outlet of the heat storage heat exchanger 15 is depressurized by the heat pump expansion valve 16 and enters the cold end inlet of the heat pump evaporator 13. The heat storage medium at the outlet of the low temperature heat storage tank 17 is heated by the cold end of the heat storage heat exchanger 15 and enters the high temperature heat storage tank 18.

[0046] See Figure 3 Open the heat release valve 19 and close the heat storage valve 12. The coal-fired power generation system is in heat release operation mode. The pressurized gasification feedwater of the coal supercritical water gasification power generation system enters the oxidation reaction inlet of the coal supercritical water gasification power generation system through the heat release valve 19 and the cold end of the heat release heat exchanger 20. The heat storage medium at the outlet of the high temperature heat storage tank 18 enters the low temperature heat storage tank 17 after being released by the hot end of the heat release heat exchanger 20.

[0047] Specifically, when the coal-fired power generation system is in heat pump thermal storage operation mode, the power generation of the coal supercritical water gasification power generation system is reduced by recovering the low-temperature thermal energy of the low-temperature flue gas, and the low-temperature thermal energy is converted into high-temperature thermal energy and stored in the high-temperature thermal storage tank 18; when the coal-fired power generation system is in heat release operation mode, the power generation of the coal supercritical water gasification power generation system is increased by releasing the thermal energy stored in the high-temperature thermal storage tank 18 to the pressurized gasification feedwater.

[0048] Example 1

[0049] A coal-fired power generation system with integrated heat pump thermal storage cycle includes a coal supercritical water gasification power generation system, a heat pump thermal storage system, and a heat release system.

[0050] The supercritical water gasification power generation system includes a supercritical water gasification reactor 1, a burner 2, a gas turbine 3, a feedwater heat exchanger 4, an organic working fluid heat exchanger 5, a cooler 6, a gas-liquid separator 7, a feedwater pump 8, an organic working fluid turbine 9, a condenser 10, and an organic working fluid pump 11. The cold end outlets of the coal and oxygen exchangers and the feedwater heat exchanger 4 are connected to the inlet of the supercritical water gasification reactor 1, respectively. Ash is discharged from the outlet of the supercritical water gasification reactor 1. The outlet of the supercritical water gasification reactor 1 is connected to the burner 2. The inlet of burner 2 is connected to the inlet of gas turbine 3; the outlet of gas turbine 3 is connected to the hot end inlet of feedwater heat exchanger 4; the hot end outlet of feedwater heat exchanger 4 is connected to the hot end inlet of organic working fluid heat exchanger 5; the hot end outlet of organic working fluid heat exchanger 5 is connected to the inlet of gas-liquid separator 7 via cooler 6; the liquid phase outlet of gas-liquid separator 7 and makeup water are connected to the cold end inlet of feedwater heat exchanger 4 via feedwater pump 8; the cold end outlet of feedwater heat exchanger 4 is connected to supercritical water gasification reactor 1 and the inlet of burner 2, respectively.

[0051] The heat pump thermal storage system, based on the supercritical coal-fired water gasification power generation system, also includes a thermal storage valve 12, a heat pump evaporator 13, a heat pump compressor 14, a thermal storage heat exchanger 15, a heat pump expansion valve 16, a low-temperature thermal storage tank 17, and a high-temperature thermal storage tank 18. The hot-end outlet of the feedwater heat exchanger 4 is diverted through the thermal storage valve 12 to the hot-end inlet of the heat pump evaporator 13. The hot-end outlet of the heat pump evaporator 13 mixes with the hot-end outlet of the organic working fluid heat exchanger 5 and connects to the inlet of the cooler 6. The cold-end outlet of the heat pump evaporator 13 connects to the inlet of the heat pump compressor 14, and the outlet of the heat pump compressor 14 connects to the hot-end inlet of the thermal storage heat exchanger 15. The hot-end outlet of the thermal storage heat exchanger 15 connects to the cold-end inlet of the heat pump evaporator 13 via the heat pump expansion valve 16. The outlet of the low-temperature thermal storage tank 17 connects to the inlet of the high-temperature thermal storage tank 18 via the cold end of the thermal storage heat exchanger 15.

[0052] Based on the supercritical coal-water gasification power generation system, the heat release system also includes a low-temperature heat storage tank 17, a high-temperature heat storage tank 18, a heat release valve 19, and a heat release heat exchanger 20; the outlet of the feedwater pump 8 is diverted through the heat release valve 19 to the cold end inlet of the heat release heat exchanger 20, and the cold end outlet of the heat release heat exchanger 20 is connected to the inlet of the burner 2; the outlet of the high-temperature heat storage tank 18 is connected to the inlet of the low-temperature heat storage tank 17 through the hot end of the heat release heat exchanger 20.

[0053] This invention, based on supercritical water gasification technology, reduces the generation of nitrogen oxides and sulfur oxides while achieving complete carbon capture of carbon dioxide, providing a novel technological path for clean, efficient, and low-carbon operation of coal-fired power generation. It fully utilizes the high-temperature thermal energy and waste heat from the supercritical water gasification process, combined with heat pump technology to improve the quality of low-temperature waste heat, achieving multi-stage energy cascade utilization and significantly reducing heat loss in the coal-fired system. Through the efficient operation of the thermal storage system, it reduces the waste of high-temperature energy and improves the overall thermal efficiency of the system. By integrating heat pump thermal storage and heat release cycles, it stores waste heat from flue gas and low-grade thermal energy during periods of low grid load and rapidly releases the stored energy during peak load periods, increasing system power generation. Through flexible switching between conventional operation, thermal storage operation, and heat release operation modes, the system can quickly respond to load changes and significantly improve the grid's peak-shaving capacity.

[0054] Example 2

[0055] An operation method for a coal-fired power generation system with an integrated heat pump thermal storage cycle is as follows: The coal-fired power generation system includes a conventional operation mode, a heat pump thermal storage operation mode, and a heat release operation mode. In the conventional operation mode, coal, oxygen, and gasification feedwater from the outlet of the feedwater heat exchanger 4 enter the supercritical water gasification reactor 1 to undergo a supercritical water gasification reaction. Ash is discharged from the outlet of the supercritical water gasification reactor 1, and syngas enters the burner 2 from the outlet of the supercritical water gasification reactor 1 to undergo a complete oxidation reaction with oxygen. Part of the gasification feedwater from the outlet of the feedwater heat exchanger 4 enters the inlet of the burner 2 to regulate the inlet temperature of the gas turbine 3. The flue gas from the outlet of the burner 2 enters the gas turbine... The gas turbine 3 expands to generate electricity. The exhaust gas from the gas turbine 3 enters the hot end of the feedwater heat exchanger 4 to preheat and vaporize the feedwater. The hot end outlet of the feedwater heat exchanger 4 enters the hot end of the organic working fluid heat exchanger 5 to heat the organic working fluid. The cold end outlet of the organic working fluid heat exchanger 5 enters the organic working fluid turbine 9 for expansion and power generation. The outlet of the organic working fluid turbine 9 passes through the condenser 10 and the organic working fluid pump 11 before entering the cold end inlet of the organic working fluid heat exchanger 5. The hot end outlet of the organic working fluid heat exchanger 5 is cooled by the cooler 6 and then enters the gas-liquid separator 7. The gas phase outlet of the gas-liquid separator 7 undergoes complete carbon capture, and the liquid phase outlet mixes with the makeup water and is pressurized by the feedwater pump 8 before entering the cold end inlet of the feedwater heat exchanger 4.

[0056] See Figure 2Heat pump thermal storage operation mode: Based on the normal operation mode, the thermal storage valve 12 is opened, and part of the flue gas from the hot end outlet of the feedwater heat exchanger 4 enters the hot end inlet of the heat pump evaporator 13 through the thermal storage valve 12. The hot end outlet of the heat pump evaporator 13 mixes with the hot end outlet of the organic working fluid heat exchanger 5 and then enters the inlet of the cooler 6. In the heat pump cycle, the cold end outlet of the heat pump evaporator 13 is pressurized by the heat pump compressor 14 and then enters the hot end inlet of the thermal storage heat exchanger 15. The hot end outlet of the thermal storage heat exchanger 15 is depressurized by the heat pump expansion valve 16 and then enters the cold end inlet of the heat pump evaporator 13. The thermal storage working fluid from the outlet of the low-temperature thermal storage tank 17 is heated by the cold end of the thermal storage heat exchanger 15 and then enters the high-temperature thermal storage tank 18.

[0057] See Figure 3 Heat release operation mode: Based on the conventional operation mode, the heat release valve 19 is opened, and part of the gasified feedwater from the outlet of the feedwater pump 8 enters the cold end inlet of the heat release heat exchanger 20 through the heat release valve 19. The cold end outlet of the heat release heat exchanger 20 enters the inlet of the burner 2. The heat storage medium from the outlet of the high temperature heat storage tank 18 enters the low temperature heat storage tank 17 after being released by the hot end of the heat release heat exchanger 20.

[0058] During off-peak load periods, the thermal storage valve 12 is opened to divert part of the flue gas from the hot end outlet of the feedwater heat exchanger 4. By recovering some of the low-temperature heat energy from the flue gas, the power generation of the organic working fluid turbine 9 is reduced. Through the integrated heat pump thermal storage cycle, the low-grade heat energy is converted into high-grade heat energy and stored in the thermal storage tank, further absorbing surplus power from the grid or renewable energy. During peak load periods, the heat release valve 19 is opened to release the heat stored in the thermal storage tank to part of the gasified feedwater at the outlet of the feedwater pump 8, thereby increasing the power generation of the gas turbine 3 and the organic working fluid turbine 9.

[0059] Finally, it should be noted that the embodiments listed above are merely one or more specific manifestations of the technical solution of this invention. Their purpose is to clearly illustrate the concept, principle, and application of this invention through specific examples, and is by no means intended to limit the scope of protection of this invention to these specific embodiments. In fact, the true value of this invention lies in its proposed technical ideas and innovations, rather than its manifestations or implementation methods.

[0060] For those skilled in the art, after thoroughly reading and understanding the technical solution of this invention, they are fully capable of making various changes, modifications, or equivalent substitutions to the specific implementation of the invention based on their own professional knowledge and skills. These changes may include, but are not limited to: adjusting the range of technical parameters, optimizing the algorithm flow to improve efficiency, and replacing some technical components to achieve better compatibility or reduce costs. As long as these modified technical solutions substantially retain the technical features claimed by the original invention, that is, they can still achieve the core functions and effects of this invention, then these changes should be considered to fall within the scope of protection of the pending claims of this invention.

[0061] Furthermore, with the continuous progress and development of technology, new technical means and methods are constantly emerging, which provides ample space for further improvement and perfection of this invention. Therefore, the scope of protection of this invention should also include reasonable and foresightful improvements and extensions based on existing technology. As long as these improvements and extensions do not depart from the basic principles and core concepts of this invention, they should be considered equivalents of this invention and are equally protected by patent rights.

Claims

1. A coal-fired power generation system integrating a heat pump thermal storage cycle, characterized in that, It includes a heat pump thermal storage system, a heat release system, and a coal supercritical water gasification power generation system; the heat pump thermal storage system includes a thermal storage valve (12), a heat pump evaporator (13), a heat pump compressor (14), a thermal storage heat exchanger (15), a heat pump expansion valve (16), a low-temperature thermal storage tank (17), and a high-temperature thermal storage tank (18); the heat release system includes a low-temperature thermal storage tank (17), a high-temperature thermal storage tank (18), a heat release valve (19), and a heat release heat exchanger (20); The low-temperature flue gas of the supercritical coal gasification power generation system is connected to the cooling inlet of the supercritical coal gasification power generation system via the heat storage valve (12) and the hot end of the heat pump evaporator (13); the cold end outlet of the heat pump evaporator (13) is connected to the heat pump compressor (14), the hot end of the heat storage heat exchanger (15), the heat pump expansion valve (16) to the cold end inlet of the heat pump evaporator (13); the outlet of the low-temperature heat storage tank (17) is connected to the inlet of the high-temperature heat storage tank (18) via the cold end of the heat storage heat exchanger (15). The pressurized gasification feedwater of the supercritical water gasification power generation system is connected to the oxidation reaction inlet of the supercritical water gasification power generation system via the heat release valve (19) and the cold end of the heat release heat exchanger (20). The outlet of the high temperature heat storage tank (18) is connected to the low temperature heat storage tank (17) via the hot end of the heat release heat exchanger (20). The supercritical water gasification power generation system includes a supercritical water gasification reactor (1), a burner (2), a gas turbine (3), a feedwater heat exchanger (4), a cooler (6), a gas-liquid separator (7), a feedwater pump (8), and an organic Rankine cycle system. The supercritical water gasification reactor (1) is connected in sequence to the burner (2), the gas turbine (3), the hot end of the feedwater heat exchanger (4), the hot end of the organic Rankine cycle system, the cooler (6), the gas-liquid separator (7), the feedwater pump (8) to the cold end of the feedwater heat exchanger (4), and the cold end outlet of the feedwater heat exchanger (4) is connected to the inlet of the supercritical water gasification reactor (1) and the burner (2), respectively. The organic Rankine cycle system includes an organic working fluid heat exchanger (5), an organic working fluid turbine (9), a condenser (10) and an organic working fluid pump (11), wherein the cold end outlet of the organic working fluid heat exchanger (5) is connected in sequence to the organic working fluid turbine (9), the condenser (10), the organic working fluid pump (11) to the cold end inlet of the organic working fluid heat exchanger (5), and the hot end of the organic working fluid heat exchanger (5) is the hot end of the organic Rankine cycle system.

2. The coal-fired power generation system with integrated heat pump thermal storage cycle according to claim 1, characterized in that, The inlet temperature of the gas turbine (3) is 700℃~1500℃.

3. A coal-fired power generation system with integrated heat pump thermal storage cycle according to claim 1, characterized in that, The outlet temperature of the cooler (6) is 20℃~35℃.

4. A coal-fired power generation system with integrated heat pump thermal storage cycle according to claim 1, characterized in that, The supercritical water gasification reactor (1) operates at a temperature of 600℃~700℃.

5. A coal-fired power generation system with integrated heat pump thermal storage cycle according to claim 1, characterized in that, The supercritical water gasification reactor (1) operates at a pressure of 25 MPa to 30 MPa.

6. A coal-fired power generation system with integrated heat pump thermal storage cycle according to claim 1, characterized in that, Molten salt is used as the heat storage medium in both the heat pump heat storage system and the heat release system.

7. An operation method for a coal-fired power generation system with an integrated heat pump thermal storage cycle, characterized in that, In a coal-fired power generation system using an integrated heat pump thermal storage cycle as described in any one of claims 1 to 6, the thermal storage valve (12) is opened and the heat release valve (19) is closed. The coal-fired power generation system is in the thermal pump thermal storage operation mode. The low-temperature flue gas from the coal supercritical water gasification power generation system enters the hot end inlet of the heat pump evaporator (13) through the thermal storage valve (12). The cold end outlet of the heat pump evaporator (13) is pressurized by the heat pump compressor (14) and enters the hot end inlet of the thermal storage heat exchanger (15). The hot end outlet of the thermal storage heat exchanger (15) is depressurized by the heat pump expansion valve (16) and enters the cold end inlet of the heat pump evaporator (13). The thermal storage medium at the outlet of the low-temperature thermal storage tank (17) is heated by the cold end of the thermal storage heat exchanger (15) and enters the high-temperature thermal storage tank (18). Open the heat release valve (19) and close the heat storage valve (12). The coal-fired power generation system is in the heat release operation mode. The pressurized gasification feedwater of the coal supercritical water gasification power generation system enters the oxidation reaction inlet of the coal supercritical water gasification power generation system through the heat release valve (19) and the cold end of the heat release heat exchanger (20). The heat storage medium at the outlet of the high temperature heat storage tank (18) enters the low temperature heat storage tank (17) after being released by the heat release heat at the hot end of the heat release heat exchanger (20).

8. The operation method of a coal-fired power generation system with integrated heat pump thermal storage cycle according to claim 7, characterized in that, When the coal-fired power generation system is in heat pump thermal storage operation mode, the power generation of the coal supercritical water gasification power generation system is reduced by recovering the low-temperature thermal energy of the low-temperature flue gas, and the low-temperature thermal energy is converted into high-temperature thermal energy and stored in the high-temperature thermal storage tank (18). When the coal-fired power generation system is in heat release operation mode, the power generation of the coal supercritical water gasification power generation system is increased by releasing the thermal energy stored in the high-temperature thermal storage tank (18) to the pressurized gasification feedwater.

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