Zero-carbon combined heat and power system and operation method

Abstract

The present invention provides a zero-carbon combined heat and power system and operation method, including a connected compressed air energy storage and release system, a hydrogen fuel cell power generation system, an ORC power generation system and a heat pump heating system, wherein the compressed air energy storage and release system exchanges heat with the heat pump heating system through a first heat exchanger; the compressed air discharged from the compressed air energy storage and release system exchanges heat with the cooling water of the hydrogen fuel cell power generation system through a second heat exchanger, and the cooling water after heat exchange exchanges heat with the liquid working medium of the ORC power generation system, so as to realize the circulation of cooling water and liquid working medium; the heat pump heating system includes a first heat pump unit and a cross-seasonal hot water storage body, the first heat pump unit increases the temperature after heat exchange with the first heat exchanger, and supplies heat to the heating network; the cross-seasonal hot water storage body realizes heat supply / heat storage through a third heat exchanger. This implementation method realizes the combined heat and power supply through the energy cascade utilization method, so that renewable energy can obtain a relatively stable output, and improves energy utilization efficiency while ensuring energy supply reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of waste energy recovery, and in particular to a zero-carbon combined heat and power system and an operation method thereof. Background Art

[0002] In the context of global climate change and energy transformation, multiple energy systems are included, such as compressed air energy storage and hydrogen energy as a clean and efficient secondary energy source.

[0003] Both hydrogen energy and compressed air energy storage have cross-seasonal, long-term energy storage characteristics, which can realize large-scale storage of electricity over a long period across seasons, and can be used for peak and frequency regulation of the power grid, improving the safety, reliability and flexibility of the power system.

[0004] However, how to further promote energy transformation, achieve low-carbon development goals, and improve the utilization rate of waste heat remains a difficult problem to be solved. Summary of the invention

[0005] The content of the present invention is used to introduce the concepts in a brief form, which will be described in detail in the detailed implementation section below. The content of the present disclosure is not intended to identify the key features or essential features of the technical solution claimed for protection, nor is it intended to limit the scope of the technical solution claimed for protection.

[0006] Some embodiments of the present invention provide a zero-carbon combined heat and power system and an operation method to solve the technical problems mentioned in the above background technology section.

[0007] In a first aspect, some embodiments of the present invention provide a zero-carbon combined heat and power system, which includes a compressed air energy storage and release system, a hydrogen fuel cell power generation system, an ORC power generation system, and a heat pump heating system connected to each other, wherein:

[0008] The compressed air energy storage and release system exchanges heat with the heat pump heating system through a first heat exchanger;

[0009] The compressed air discharged from the compressed air energy storage and release system exchanges heat with the cooling water of the hydrogen fuel cell power generation system through the second heat exchanger, and the cooling water after heat exchange exchanges heat with the liquid working medium of the ORC power generation system, so as to realize the circulation of cooling water and liquid working medium;

[0010] The heat pump heating system includes a first heat pump unit and an inter-seasonal hot water storage body. The first heat pump unit increases the temperature after heat exchange with the first heat exchanger and supplies heat to the heating network; the inter-seasonal hot water storage body realizes heat supply / heat storage through the third heat exchanger.

[0011] In a second aspect, some embodiments of the present invention provide an operation method for the above-mentioned zero-carbon combined heat and power system, the method comprising:

[0012] In the first cogeneration mode, the compressed air energy storage and release system, the hydrogen fuel cell power generation system and the ORC power generation system supply power to the grid, and the compressed air and cooling water, as well as the cooling water and liquid working fluid, exchange heat once; the first heat pump unit and the inter-seasonal hot water storage body supply energy to the heating network through the first heat exchanger and the third heat exchanger respectively;

[0013] In the second cogeneration mode, the compressed air discharged from the compressed air energy storage and release system is discharged after passing through the second heat exchanger, and is used to increase the temperature of the liquid working medium and realize the circulation of the liquid working medium; the heating process of the second cogeneration mode is the same as that of the first cogeneration mode;

[0014] In the power supply and heat storage mode in the non-heating season, after the heat network supplies heat through the first heat pump unit, the heat is stored in the inter-seasonal hot water storage body through the third heat exchange component; the power supply and heat storage mode in the non-heating season is the same as the power supply process of the first cogeneration mode;

[0015] In the energy storage and heating / heat storage mode, the hydrogen fuel cell power generation system and ORC power generation system stop working, and the compressed air energy storage and release system stores compressed air; the first heat pump unit and the cross-seasonal hot water storage body provide heating / heat storage.

[0016] The above embodiments of the present invention have the following beneficial effects:

[0017] The energy cascade utilization method of compressed air energy storage and release system, hydrogen power generation system and ORC power generation system realizes the combined supply of heat and electricity, so that renewable energy can obtain relatively stable output, ensuring the reliability of energy supply while improving energy utilization efficiency.

[0018] Specifically, between the above-mentioned compressed air energy storage and release system, hydrogen fuel cell power generation system, and ORC power generation system, the compressed air exchanges heat with the cooling water through the second heat exchanger, so that the compressed air is cooled to a temperature suitable for the hydrogen fuel cell reaction. The cooling water exchanges heat with the liquid working fluid through the heat storage evaporator, so that the cooling water temperature is reduced and can return to the hydrogen fuel cell for continued cooling, thereby realizing the circulation of cooling water. The increase in the temperature of the liquid working fluid can provide a heat source for the ORC power generation system and realize the recycling of the liquid working fluid. In this way, the heat of the compressed air is effectively utilized, and the utilization rate of waste heat is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of an embodiment of a zero-carbon combined heat and power system of the present invention;

[0021] Figure 2 It is a structural schematic diagram of an embodiment of the first cogeneration mode of the present invention;

[0022] Figure 3 It is a structural schematic diagram of an embodiment of the second cogeneration mode of the present invention;

[0023] Figure 4 It is a structural schematic diagram of an embodiment of the power supply and heat storage mode in the non-heating season of the present invention;

[0024] Figure 5 It is a structural schematic diagram of an embodiment of the energy storage and heating mode of the present invention;

[0025] Figure 6 It is a structural schematic diagram of another embodiment of the energy storage and heating mode of the present invention;

[0026] Figure 7 It is a structural schematic diagram of an embodiment of the energy storage and heat storage mode of the present invention.

[0027] Description of reference numerals:

[0028] 1. Multi-stage compressor unit; 2. First heat exchanger; 3. Gas storage tank; 4. Multi-stage expansion unit; 5. First generator; 6. Second heat exchanger; 7. Hydrogen fuel cell; 8. Hydrogen storage tank; 9. Circulation pump; 10. Thermal storage evaporator; 11. Fourth heat exchanger; 12. Expansion machine; 13. Second generator; 14. Condenser; 15. Circulation pump; 16. Circulation pump; 17. First heat pump unit; 18. Circulation pump; 19. Circulation pump; 20. Circulation pump; 21. Second heat pump unit; 22. Circulation pump; 23. Inter-seasonal hot water storage body; 24. Circulation pump; 25. Circulation pump; 26. Third heat exchanger; 27. Circulation pump; 28. Air filter; 29. ​​Ejector. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The present disclosure will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0033] First see Figure 1 , Figure 1 FIG. 1 is a schematic diagram of the structure of an embodiment of the zero-carbon combined heat and power system of the present invention. Figure 1 As shown, the zero-carbon cogeneration system includes a connected compressed air energy storage and release system, a hydrogen fuel cell power generation system, an ORC power generation system and a heat pump heating system.

[0034] The compressed air energy storage and release system includes a multi-stage compressor unit 1, and the final exhaust end of the multi-stage compressor unit 1 is connected to the gas side inlet of the first heat exchanger 2. The first heat exchanger 2 is also connected to the heat pump heating system, so that it can exchange heat with the compressed air, reduce the temperature of the compressed air, and provide heat for the heat pump heating system. The gas side outlet of the first heat exchanger 2 is connected to a gas storage tank 3, and the compressed gas can be stored in the gas storage tank 3 to achieve energy storage of compressed air. The outlet end of the gas storage tank 3 is connected to a multi-stage expansion unit 4, and the compressed air in the gas storage tank 3 can make the multi-stage expansion unit 4 expand and do work, so that the first generator 5 connected to the multi-stage expansion unit 4 generates electricity. The first generator 5 is also connected to the power grid through a cable, so as to realize the power generation cycle of compressed air.

[0035] The exhaust end of the multi-stage expansion unit 4 is also connected to the hydrogen fuel cell power generation system. Specifically, the hydrogen fuel cell power generation system includes a hydrogen fuel cell 7, the anode of the hydrogen fuel cell 7 is connected to a hydrogen storage tank 8 through a pipeline, and the hydrogen storage tank 8 is used to transport hydrogen to the anode. An ejector 29 is also provided between the anode and the hydrogen storage tank 8 to improve the utilization rate of hydrogen.

[0036] The hydrogen fuel cell 7 power generation system further includes a second heat exchanger 6, the exhaust end of the multi-stage expansion unit 4 is connected to the gas inlet of the second heat exchanger 6, and the gas outlet of the second heat exchanger 6 is connected to the cathode of the hydrogen fuel cell 7 via a pipeline. An air filter 28 may also be provided between the second heat exchanger 6 and the cathode for filtering compressed air.

[0037] The hydrogen fuel cell 7 is also connected to the power grid via a cable. In the working state, the hydrogen provided by the hydrogen storage tank 8 reacts chemically with the compressed air to generate electrical energy, which supplies energy to the power grid.

[0038] The cooling water outlet of the hydrogen fuel cell 7 can be connected to the water side inlet of the second heat exchanger 6 through a circulation pump 9. The water side outlet of the second heat exchanger 6 exchanges heat with the ORC power generation system to reduce the cooling water temperature, and finally connected back to the cooling water inlet of the hydrogen fuel cell 7.

[0039] That is to say, the second heat exchanger 6 allows the compressed air to exchange heat with the cooling water discharged from the hydrogen fuel cell 7, so that the temperature of the compressed air is reduced to match the reaction temperature of the hydrogen fuel cell 7. The cooling water temperature is increased, and after heat exchange with the ORC power generation system, it provides heat for the ORC power generation system, and at the same time, the cooling water temperature is reduced to match the cooling temperature of the hydrogen fuel cell 7, so that the cooling water is circulated and used, and the heat of the compressed air can be effectively used.

[0040] The ORC power generation system includes a thermal storage evaporator 10, an expander 12, and a second generator 13. The working fluid side outlet of the thermal storage evaporator 10 is connected to the expander 12. Both ends of the second generator 13 are connected to the expander 12 and the power grid respectively. The working fluid outlet of the expander 12 is also connected to the working fluid side inlet of the thermal storage evaporator 10 through a pipeline.

[0041] The water-side inlet of the thermal storage evaporator 10 is communicated with the water-side outlet of the second heat exchanger 6 , and the water-side outlet of the thermal storage evaporator 10 is communicated with the cooling water inlet of the hydrogen fuel cell 7 .

[0042] In the working state, the liquid working medium is transmitted by the circulating pump 15, and heat is exchanged with the cooling water in the thermal storage evaporator 10 to increase the temperature. After the expander 12 performs work, the second generator 13 generates electricity, thereby supplying energy to the power grid. The liquid working medium is discharged from the working medium outlet of the expander 12, and will be transmitted by the circulating pump 15 again and heat exchanged with the cooling water through the thermal storage evaporator 10, thus realizing the circulation of the liquid working medium, thereby effectively utilizing the heat of the cooling water.

[0043] Overall, the energy cascade utilization method of compressed air energy storage and release system, hydrogen power generation system, and ORC power generation system realizes the combined supply of heat and electricity, so that renewable energy can obtain relatively stable output, ensuring the reliability of energy supply while improving energy utilization efficiency.

[0044] Specifically, between the above-mentioned compressed air energy storage and release system, hydrogen fuel cell power generation system, and ORC power generation system, the compressed air exchanges heat with the cooling water through the second heat exchanger 6, so that the compressed air is cooled to a temperature suitable for the reaction of the hydrogen fuel cell 7. The cooling water exchanges heat with the liquid working fluid through the heat storage evaporator 10, so that the cooling water temperature is reduced and can return to the hydrogen fuel cell 7 for continued cooling, thereby realizing the circulation of cooling water. The increase in the temperature of the liquid working fluid can provide a heat source for the ORC power generation system and realize the recycling of the liquid working fluid. In this way, the heat of the compressed air is effectively utilized, and the utilization rate of waste heat is improved.

[0045] The heat pump heating system comprises a first heat pump unit 17, the water side outlet of the first heat pump unit 17 is connected to the water side inlet of the first heat exchanger 2 via a pipeline and a circulating pump 16. The water side outlet of the second heat exchanger 6 is connected to the water side inlet of the first heat pump unit 17. The condensation side outlet of the first heat pump unit 17 is connected to the water supply end of the heat network via a pipeline, and the return water end of the heat network is connected to the condensation side inlet of the first heat pump unit 17 via a pipeline and a circulating pump 18.

[0046] In the working state, water circulates between the first heat pump unit 17 and the first heat exchanger 2 under the transmission of the circulation pump 16, and the circulating water exchanges heat with the compressed air through the first heat exchanger 2 to increase the temperature. The heated circulating water provides a low-temperature heat source for the first heat pump unit 17. After the first heat pump unit 17 increases the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating cycle.

[0047] The heat pump heating system may also include an inter-seasonal hot water storage body 23, which includes two sets of circulating pipelines arranged in parallel. The outlet and inlet of the first circulating pipeline are respectively connected to the primary side inlet and outlet of the third heat exchanger 26 through a circulating pump 25 or a circulating pump 24 and a pipeline. The transmission direction of the circulating pump 25 is opposite to that of the circulating pump 24, so as to realize the energy supply and energy storage of the inter-seasonal hot water storage body 23. The secondary side inlet and outlet of the third heat exchanger 26 are connected to the return water end of the heat network and the water supply end of the heat network through a circulating pump 27 and a pipeline. In this way, the circulating water in the inter-seasonal hot water storage body 23 is heat-exchanged with the return water of the heat network through the third heat exchanger 26, thereby completing the heating / heat storage cycle.

[0048] The outlet and inlet of the second circulation pipeline are respectively connected to the water side inlet and water side outlet of the first heat pump unit 17 through the circulation pump 25 and the pipeline. The inter-seasonal hot water storage body 23 provides a low-temperature heat source for the first heat pump unit 17. After the first heat pump unit 17 raises the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating cycle.

[0049] Further, the heat pump heating system may also include a fourth heat exchanger 11, the primary side inlet and outlet of the fourth heat exchanger 11 are respectively connected to the water side outlet of the thermal storage evaporator 10 and the cooling water inlet of the hydrogen fuel cell 7 through pipelines. The secondary side inlet and outlet of the fourth heat exchanger 11 are respectively connected to the return water end of the heat network and the water supply end of the heat network through a circulating pump 19 and a pipeline. Thus, the return water of the heat network exchanges heat with the cooling water through the fourth heat exchanger 11, thereby completing the cycle of heating, making full use of the waste heat of the cooling water, and improving the waste heat utilization rate.

[0050] Furthermore, the heat pump heating system may also include a condenser 14 and a second heat pump unit 21 , wherein the working fluid side inlet and outlet of the condenser 14 are respectively connected to the working fluid outlet of the expander 12 and the working fluid side inlet of the thermal storage evaporator 10 through pipelines.

[0051] The water side inlet and outlet of the condenser 14 are respectively connected to the water side outlet and inlet of the second heat pump unit 21 through a circulating pump 20 and a pipeline. The condensing side outlet and inlet of the second heat pump unit 21 are respectively connected to the water supply end and the return end of the heat network through a circulating pump 22 and a pipeline.

[0052] In the working state, the liquid working medium exchanges heat with the circulating water through the condenser 14, and the heated circulating water provides a low-temperature heat source for the second heat pump unit 21. After the second heat pump unit 21 raises the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating cycle. In this process, the waste heat of the liquid working medium can be fully utilized to improve the waste heat utilization rate.

[0053] The present invention also provides an operating method for a zero-carbon combined heat and power system, which can be used for the zero-carbon combined heat and power system in the above embodiments. The operating method includes multiple operating modes.

[0054] See also Figure 2 , Figure 2 FIG. 1 is a schematic diagram of a structure of an embodiment of the first cogeneration mode of the present invention. Figure 3 As shown, in the first cogeneration mode, valves V2, V3, V4, V6, V7, V8, V9, V10, V11, V12, V13, V17, V19, V20, V21, V22, and V23 are opened, and other valves are closed.

[0055] During the power supply process, the compressed air in the gas storage tank 3 can cause the multi-stage expansion unit 4 to expand and perform work, thereby enabling the first generator 5 connected to the multi-stage expansion unit 4 to generate electricity.

[0056] The hydrogen storage tank 8 transports hydrogen to the anode of the hydrogen fuel cell 7. The compressed air discharged from the terminal exhaust end of the multi-stage expansion unit 4 is cooled by heat exchange with the cooling water of the hydrogen fuel cell 7 through the second heat exchanger 6 and then transported to the cathode of the hydrogen fuel cell 7. After electrochemical reaction to generate electricity, it is connected to the power grid.

[0057] The cooling water is heated by the second heat exchanger 6 and then enters the heat storage evaporator 10 to exchange heat with the liquid working medium. The heated liquid working medium performs work through the expander 12, so that the second generator 13 generates electricity, thereby supplying energy to the power grid.

[0058] During the heating process, water circulates between the first heat pump unit 17 and the first heat exchanger 2 under the transmission of the circulation pump, and the circulating water exchanges heat with the compressed air through the first heat exchanger 2 to increase its temperature. The heated circulating water provides a low-temperature heat source for the first heat pump unit 17, and after the first heat pump unit 17 increases the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating cycle.

[0059] In addition, the inter-seasonal hot water storage body 23 adopts the first circulation pipeline and the circulation pump 25 to exchange heat with the return water of the heating network through the third heat exchanger 26, thereby completing the heating cycle.

[0060] Furthermore, the return water of the heat network exchanges heat with the cooling water through the fourth heat exchanger 11, thereby completing the heat supply cycle, making full use of the waste heat of the cooling water and improving the waste heat utilization rate.

[0061] Furthermore, the liquid working medium exchanges heat with the circulating water through the condenser 14, and the heated circulating water provides a low-temperature heat source for the second heat pump unit 21. After the second heat pump unit 21 raises the temperature of the low-temperature heat source, it can exchange heat with the return water of the heating network, thereby completing the heating cycle. Figure 3 , Figure 3 FIG. 1 is a schematic diagram of a structure of an embodiment of the second cogeneration mode of the present invention. Figure 3 As shown, in the second cogeneration mode, valves V1, V5, V6, V7, V8, V9, V10, V11, V12, V13, V17, V19, V20, V21, V22, and V23 are opened, and other valves are closed.

[0062] During the power supply process, the compressed air in the gas storage tank 3 can cause the multi-stage expansion unit 4 to expand and perform work, thereby enabling the first generator 5 connected to the multi-stage expansion unit 4 to generate electricity.

[0063] The compressed air discharged from the exhaust end of the multi-stage expansion unit 4 is discharged after passing through the second heat exchanger 6. The compressed air can exchange heat with the circulating water passing through the heat storage evaporator 10, so that the heated circulating water exchanges heat with the liquid working medium. After the heated liquid working medium passes through the expander 12 to do work, the second generator 13 generates electricity, thereby supplying energy to the power grid.

[0064] The heating process of the second cogeneration mode is the same as the heating process of the first cogeneration mode, and will not be described again here.

[0065] See also Figure 4 , Figure 4 FIG. 1 is a schematic diagram of a structure of an embodiment of the power supply and heat storage mode in the non-heating season of the present invention. Figure 4 As shown, in the power supply and heat storage mode in the non-heating season, valves V2, V3, V4, V6, V7, V8, V9, V10, V11, V12, V13, V16, V18, V20, V21, V22, and V23 are opened, and other valves are closed.

[0066] The power supply process of the power supply and heat storage mode in the non-heating season is the same as the power supply process of the first cogeneration mode, and will not be repeated here.

[0067] During the heat storage process, water circulates between the first heat pump unit 17 and the first heat exchanger 2 under the transmission of the circulation pump 16, and the circulating water exchanges heat with the compressed air through the first heat exchanger 2 to increase its temperature. The heated circulating water provides a low-temperature heat source for the first heat pump unit 17. After the first heat pump unit 17 increases the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating of the heat network.

[0068] Furthermore, the return water of the heating network exchanges heat with the cooling water through the fourth heat exchanger 11, thereby completing the heating supply to the heating network.

[0069] Furthermore, the liquid working medium exchanges heat with the circulating water through the condenser 14, and the heated circulating water provides a low-temperature heat source for the second heat pump unit 21. After the second heat pump unit 21 heats the low-temperature heat source, it can exchange heat with the return water of the heating network, thereby completing the heating of the heating network.

[0070] Since there are no heat users in the heat network at this time, the heat is stored in the inter-seasonal hot water storage body 23 through the third heat exchanger 26 and the circulation pump 24 .

[0071] See also Figure 5 , Figure 5 FIG. 1 is a schematic diagram of a structure of an embodiment of the energy storage and heating mode of the present invention. Figure 5 As shown, in the energy storage and heating mode, the hydrogen fuel cell power generation system and the ORC power generation system stop working, valves V10, V11, V12, V13, V17, V19, V20, V21, V22, and V23 are opened, and other valves are closed.

[0072] During the energy storage process, the external air is compressed by the multi-stage compressor unit 1 to generate compressed air. After the compressed air is heat exchanged by the heat exchanger, it enters the air storage tank 3 to complete the energy storage.

[0073] During the heating process, water circulates between the first heat pump unit 17 and the first heat exchanger 2 under the transmission of the circulation pump, and the circulating water exchanges heat with the compressed air through the first heat exchanger 2 to increase its temperature. The heated circulating water provides a low-temperature heat source for the first heat pump unit 17, and after the first heat pump unit 17 increases the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating cycle.

[0074] In addition, the inter-seasonal hot water storage body 23 passes through the first circulation pipeline, so that the circulating water in the inter-seasonal hot water storage body 23 exchanges heat with the return water of the heating network through the third heat exchanger 26 and the circulation pump 25, thereby completing the heating.

[0075] See also Figure 6 , Figure 6 FIG. 1 is a structural diagram of another embodiment of the energy storage and heating mode of the present invention. Figure 6 As shown, when the circulating water in the inter-seasonal hot water storage body 23 drops to a preset temperature and the gas storage tank 3 is full, valves V12, V13, V14, V15, V17, and V19 can be opened and other valves can be closed.

[0076] During the heating process, the seasonal hot water storage body 23 passes through the second circulation pipeline. The circulating water of the seasonal hot water storage body can provide a low-temperature heat source for the first heat pump unit 17. After the first heat pump unit 17 raises the temperature of the low-temperature heat source, it can exchange heat with the return water of the heating network to complete the heating.

[0077] See also Figure 7 , Figure 7 FIG. 1 is a schematic diagram of a structure of an embodiment of the energy storage and heat storage mode of the present invention. Figure 7 As shown, in the energy storage and heat storage mode, the hydrogen fuel cell power generation system and the ORC power generation system also stop working, and valves V10, V11, V12, V13, V16, V18, V20, V21, V22, and V23 are opened, and other valves are closed.

[0078] The energy storage process of this energy storage and heat storage mode is the same as that of the above energy storage and heating mode, and will not be repeated here.

[0079] During the heat storage process, water circulates between the first heat pump unit 17 and the first heat exchanger 2 under the transmission of the circulation pump 16, and the circulating water exchanges heat with the compressed air through the first heat exchanger 2 to increase its temperature. The heated circulating water provides a low-temperature heat source for the first heat pump unit 17. After the first heat pump unit 17 increases the temperature of the low-temperature heat source, it can exchange heat with the return water of the heat network, thereby completing the heating of the heat network.

[0080] Since there are no heat users in the heat network at this time, the heat is stored in the inter-seasonal hot water storage body 23 through the third heat exchanger 26 and the circulation pump 24 .

[0081] The heat pump unit and heat exchanger of the present invention are auxiliary equipment for heating. The system operation is mainly based on the compressed air storage, hydrogen power generation and ORC power generation needs. The heating and heat storage modes are switched in real time to ensure the stable operation of the system. When the power grid does not need to supply power, the system operates in a single heating mode according to the demand of the heating network.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A zero-carbon combined heat and power system, characterized in that: It includes a connected compressed air energy storage and release system, a hydrogen fuel cell power generation system, an ORC power generation system and a heat pump heating system, among which: The compressed air energy storage and release system exchanges heat with the heat pump heating system through a first heat exchanger; The compressed air discharged from the compressed air energy storage and release system exchanges heat with the cooling water of the hydrogen fuel cell power generation system through the second heat exchanger, and the cooling water after heat exchange exchanges heat with the liquid working medium of the ORC power generation system, so as to realize the circulation of cooling water and liquid working medium; The heat pump heating system includes a first heat pump unit and an inter-seasonal hot water storage body. The first heat pump unit increases the temperature after heat exchange with the first heat exchanger and supplies heat to the heating network; the inter-seasonal hot water storage body realizes heat supply / heat storage through the third heat exchanger.

2. The zero-carbon combined heat and power system according to claim 1, characterized in that: The compressed air energy storage and release system comprises a multi-stage compressor unit, an air storage tank, a multi-stage expansion unit and a first generator which are connected to each other, wherein the first heat exchanger is connected between the multi-stage compressor unit and the air storage tank.

3. The zero-carbon combined heat and power system according to claim 2, characterized in that: The hydrogen fuel cell power generation system comprises a hydrogen storage tank and a hydrogen fuel cell which are connected in sequence, and the compressed air discharged from the end of the multi-stage expansion unit is connected to the cathode of the hydrogen fuel cell through the second heat exchanger.

4. The zero-carbon combined heat and power system according to claim 3, characterized in that: The cooling water of the hydrogen fuel cell passes through the second heat exchanger and the ORC power generation system in sequence and then returns to the cooling water inlet of the hydrogen fuel cell.

5. The zero-carbon combined heat and power system according to claim 4, characterized in that: The ORC power generation system includes a thermal storage evaporator, an expander, and a second generator 13 connected in sequence, and a working medium outlet of the expander is connected to the thermal storage evaporator.

6. The zero-carbon combined heat and power system according to claim 5, characterized in that: The cooling water after heat exchange in the second heat exchanger passes through the heat storage evaporator and can exchange heat with the liquid working medium discharged from the expander.

7. The zero-carbon combined heat and power system according to claim 1, characterized in that: The inter-seasonal hot water storage body is also connected to the first heat pump unit to provide a low-temperature heat source.

8. The zero-carbon combined heat and power system according to claim 1, characterized in that: The heat pump heating system further includes a fourth heat exchanger, which is used to exchange heat between cooling water passing through the ORC power generation system and return water of the heat network.

9. The zero-carbon combined heat and power system according to claim 5, characterized in that: The heat pump heating system also includes a connected condenser and a second heat pump unit. The condenser is used to provide a low-temperature heat source for the second heat pump unit by exchanging heat with the liquid working fluid discharged from the expander; the second heat pump unit raises the temperature of the low-temperature heat source and then supplies heat to the heating network.

10. A method for operating a zero-carbon combined heat and power system as claimed in any one of claims 1 to 9, the method comprising: In the first cogeneration mode, the compressed air energy storage and release system, the hydrogen fuel cell power generation system and the ORC power generation system supply power to the grid, and the compressed air and cooling water, as well as the cooling water and liquid working fluid, exchange heat once; the first heat pump unit and the inter-seasonal hot water storage body supply energy to the heating network through the first heat exchanger and the third heat exchanger respectively; In the second cogeneration mode, the compressed air discharged from the compressed air energy storage and release system is discharged after passing through the second heat exchanger, and is used to increase the temperature of the liquid working medium and realize the circulation of the liquid working medium; the heating process of the second cogeneration mode is the same as that of the first cogeneration mode; In the power supply and heat storage mode in the non-heating season, after the heat network supplies heat through the first heat pump unit, the heat is stored in the inter-seasonal hot water storage body through the third heat exchange component; the power supply and heat storage mode in the non-heating season is the same as the power supply process of the first cogeneration mode; In the energy storage and heating / heat storage mode, the hydrogen fuel cell power generation system and ORC power generation system stop working, and the compressed air energy storage and release system stores compressed air; the first heat pump unit and the cross-seasonal hot water storage body provide heating / heat storage.

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