Hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system

Abstract

The present application relates to a kind of hydrogen heat and power tri-generation liquid carbon dioxide energy storage system, a kind of hydrogen heat and power tri-generation liquid carbon dioxide energy storage system, comprising: renewable energy power generation device, energy storage module and hydrogen production module.Energy storage module includes molten salt energy storage loop, liquid carbon dioxide energy storage loop, first heat exchanger and second heat exchanger, hydrogen production module includes heat conducting oil loop and methanol hydrogen production loop.Renewable energy power generation device is connected with molten salt energy storage loop, the hot side of first heat exchanger is connected with molten salt energy storage loop, the cold side of first heat exchanger is connected with liquid carbon dioxide energy storage loop, the hot side of second heat exchanger is connected with liquid carbon dioxide energy storage loop, the cold side of second heat exchanger is connected with heat conducting oil loop, heat conducting oil loop is connected with methanol hydrogen production loop reactor, gasifier.The present application utilizes the heat contained in turbine exhaust during energy release phase of energy storage system to provide energy for methanol reforming hydrogen production process, with the advantages of lower hydrogen production cost, higher energy utilization rate etc.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to a hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system. BACKGROUND

[0002] In order to cope with the serious challenges brought by the increasing depletion of fossil fuels and environmental problems caused by the combustion of fossil fuels, China has vigorously developed renewable energy and continuously increased the installed capacity of renewable energy such as wind power and solar power. However, due to the volatility and intermittency of renewable energy, large-scale grid connection will have a great impact on the power grid, threatening the stability and safety of the power grid. Energy storage systems can achieve "peak shaving and valley filling", balance the power demand on the generation side and the load side of the power grid, reduce the impact of renewable energy grid connection on the power grid, and maintain the safety of the power grid.

[0003] Compressed gas liquid energy storage has great development prospects without geographical restrictions. Carbon dioxide working medium has a large density in the running state, and the volume of the components of the cycle system using carbon dioxide as the working medium is small, the structure is compact, and the system cost is low. Moreover, liquid carbon dioxide has a high temperature, and it is easier to achieve liquid storage and has a larger energy storage density when using carbon dioxide as the working medium of the energy storage system. Compared with traditional energy storage systems that use compressors to compress the working medium, using a pump to increase the pressure of the working medium can greatly reduce the compression work and improve the efficiency of the energy storage system.

[0004] Hydrogen energy is one of the important clean energies, and there are more and more researches on hydrogen production and utilization worldwide. Hydrogen is a clean and efficient fuel, and its energy density is 2.68 times that of gasoline. Water is the only product of its combustion, and it is considered to be one of the most potential fossil fuel alternatives. In the context of energy saving and emission reduction, hydrogen energy has become the most potential alternative energy in this century due to its high efficiency and cleanliness. Hydrogen production technology directly affects the cost and development of hydrogen energy. Methanol is the most potential hydrogen source in reforming reaction, and has the advantages of simple structure, easy transportation, easy availability, low reforming reaction temperature, and high hydrogen content in reforming products.

[0005] The working medium at the turbine outlet of the liquid carbon dioxide energy storage system still has a lot of heat during the energy release stage, and the methanol reforming to produce hydrogen is a strong endothermic reaction. Coupling the liquid carbon dioxide energy storage system with the methanol reforming to produce hydrogen system and using the heat contained in the working medium at the turbine outlet of the energy storage system to provide energy for the methanol reforming to produce hydrogen system can not only make the energy of the energy storage system be reasonably utilized and improve the operating efficiency of the energy storage system, but also reduce the operating cost of the methanol reforming to produce hydrogen system. However, there is no structure in the related art that combines the liquid carbon dioxide energy storage system with the methanol reforming to produce hydrogen. SUMMARY

[0006] The present application aims to at least solve one of the technical problems in the related art to some extent.

[0007] To this end, the embodiment of the present application provides a hydrogen-heat-power-trigeneration liquid carbon dioxide energy storage system, which has the advantages of low hydrogen production cost and high energy utilization rate.

[0008] The hydrogen-heat-power-trigeneration liquid carbon dioxide energy storage system provided by the embodiment of the present application comprises a renewable energy power generation device, an energy storage module and a hydrogen production module; the energy storage module comprises a molten salt energy storage loop, a liquid carbon dioxide energy storage loop, a first heat exchanger and a second heat exchanger, the renewable energy power generation device is connected with the molten salt energy storage loop, the hot side of the first heat exchanger is connected with the molten salt energy storage loop, the cold side of the first heat exchanger is connected with the liquid carbon dioxide energy storage loop, and the hot side of the second heat exchanger is connected with the liquid carbon dioxide energy storage loop; the hydrogen production module comprises a heat conducting oil loop and a methanol hydrogen production loop, the methanol hydrogen production loop comprises a reactor and a gasifier, and the heat conducting oil loop is connected with the cold side of the second heat exchanger, the tube side of the reactor and the hot side of the gasifier.

[0009] When the grid load demand is low, the hydrogen-heat-power-trigeneration liquid carbon dioxide energy storage system provided by the embodiment of the present application can not be connected to the grid, the system is in the energy storage stage, the electric energy is stored in the form of heat energy through the molten salt energy storage loop, and the electric energy is stored in the form of pressure energy through the liquid carbon dioxide energy storage loop. When the grid load is high, the system is in the energy release stage, the energy stored in the energy storage stage is converted into electric energy to supply the grid, the heat contained in the turbine exhaust gas can be transferred to the heat conducting oil heat storage medium through the second heat exchanger, and the gasified methanol raw material liquid and the methanol reforming hydrogen production reaction are provided with energy through the gasifier and the reactor. Therefore, the hydrogen-heat-power-trigeneration liquid carbon dioxide energy storage system provided by the embodiment of the present application can absorb and store the heat energy of the turbine outlet carbon dioxide working medium in the energy release stage through the heat conducting oil, so as to gasify the methanol raw material liquid and provide heat for the reactor to maintain the methanol reforming hydrogen production reaction, so that the heat of the carbon dioxide working medium is reasonably and scientifically utilized, the energy cascade utilization is realized, the production cost of hydrogen is greatly reduced, and the influence of the hydrogen production process on the environment is reduced.

[0010] In some embodiments, the liquid carbon dioxide circuit comprises a turbine, a regenerator, a condenser, a low pressure carbon dioxide storage tank, a carbon dioxide working fluid pump, a first cooler, and a high pressure carbon dioxide storage tank, the outlet of the low pressure carbon dioxide storage tank is connected to the inlet of the carbon dioxide working fluid pump, the outlet of the carbon dioxide working fluid pump is connected to the hot side inlet of the first cooler, the hot side outlet of the first cooler is connected to the inlet of the high pressure carbon dioxide storage tank, the outlet of the high pressure carbon dioxide storage tank is connected to the cold side inlet of the regenerator, the cold side outlet of the regenerator is connected to the cold side inlet of the first heat exchanger, the cold side outlet of the first heat exchanger is connected to the inlet of the turbine, the outlet of the turbine is connected to the hot side inlet of the second heat exchanger, the hot side outlet of the second heat exchanger is connected to the hot side inlet of the regenerator, the hot side outlet of the regenerator is connected to the inlet of the condenser, the outlet of the condenser is connected to the inlet of the low pressure carbon dioxide storage tank.

[0011] In some embodiments, the carbon dioxide working fluid pump is connected to the renewable energy power generation device, the renewable energy power generation device can supply power to the carbon dioxide working fluid pump; and / or, the renewable energy power generation device is a wind farm.

[0012] In some embodiments, the molten salt energy storage circuit comprises an electrically heated boiler, a high temperature molten salt storage tank, and a low temperature molten salt storage tank, the renewable energy power generation device is used to supply power to the electrically heated boiler, the outlet of the low temperature molten salt storage tank is connected to the inlet of the electrically heated boiler, the outlet of the electrically heated boiler is connected to the inlet of the high temperature molten salt storage tank, the outlet of the high temperature molten salt storage tank is connected to the hot side inlet of the first heat exchanger, the hot side outlet of the first heat exchanger is connected to the inlet of the low temperature molten salt storage tank.

[0013] In some embodiments, the heat conducting oil circuit comprises a high temperature heat conducting oil storage tank, a heat conducting oil pump, and a low temperature heat conducting oil storage tank, the outlet of the high temperature heat conducting oil storage tank is connected to the inlet of the heat conducting oil pump, the outlet of the heat conducting oil pump is connected to the tube side inlet of the reactor, the tube side outlet of the reactor is connected to the hot side inlet of the gasifier, the hot side outlet of the gasifier is connected to the inlet of the low temperature heat conducting oil storage tank, the outlet of the low temperature heat conducting oil storage tank is connected to the cold side inlet of the second heat exchanger, the cold side outlet of the second heat exchanger is connected to the inlet of the high temperature heat conducting oil tank.

[0014] In some embodiments, the methanol-to-hydrogen circuit further comprises a feed device for supplying methanol feedstock, the feed device being connected to the cold side inlet of the preheater, the cold side outlet of the preheater being connected to the cold side inlet of the gasifier, the cold side outlet of the gasifier being connected to the shell side inlet of the reactor, the shell side outlet of the reactor being connected to the hot side inlet of the preheater, the hot side outlet of the preheater being connected to the hot side inlet of the second cooler, the hot side outlet of the second cooler being connected to the inlet of the gas-liquid separator, the gas side outlet of the gas-liquid separator being connected to the inlet of the pressure swing adsorber, the outlet of the pressure swing adsorber being connected to the inlet of the hydrogen storage tank.

[0015] In some embodiments, the feed device comprises a desalted water storage tank for storing desalted water, a methanol storage tank for storing methanol, and a methanol feedstock liquid pump, water in the desalted water storage tank and methanol in the methanol storage tank being mixed in a certain ratio and then entering the methanol feedstock liquid pump, the outlet of the methanol feedstock liquid pump being connected to the cold side inlet of the preheater.

[0016] In some embodiments, the liquid side outlet of the gas-liquid separator is connected to the inlet of the methanol feedstock liquid pump, and the liquid material separated by the liquid side outlet of the gas-liquid separator can enter the inlet of the methanol feedstock liquid pump.

[0017] In some embodiments, at least one of the condenser, the first cooler and the second cooler is connected to a domestic hot water circuit.

[0018] In some embodiments, the shell side of the reactor is filled with a catalyst required for methanol reforming to produce hydrogen. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a schematic diagram of a hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system according to an embodiment of the present application.

[0020] REFERENCE NUMERALS:

[0021] 1. Wind farm; 2. Electric heating boiler; 3. High-temperature molten salt storage tank; 4. Low-temperature molten salt storage tank; 5. First heat exchanger; 6. Turbine; 7. Second heat exchanger; 8. Regenerator; 9. Condenser; 10. Low-pressure carbon dioxide storage tank; 11. Carbon dioxide working fluid pump; 12. First cooler; 13. High-pressure carbon dioxide storage tank; 14. High-temperature heat transfer oil storage tank; 15. Heat transfer oil pump; 16. Reactor; 17. Vaporizer; 18. Low-temperature heat transfer oil storage tank; 19. Demineralized water storage tank; 20. Methanol storage tank; 21. Methanol feedstock pump; 22. Preheater; 23. Second cooler; 24. Gas-liquid separator; 25. Pressure swing adsorption unit; 26. Hydrogen storage tank. Detailed Implementation

[0022] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0023] The following is a reference appendix. Figure 1 A hydrogen-thermal-powered liquid carbon dioxide energy storage system according to an embodiment of the present invention is described.

[0024] like Figure 1 As shown, a hydrogen-thermal-power combined cycle (CHP) liquid carbon dioxide energy storage system according to an embodiment of the present invention includes: a renewable energy power generation device, an energy storage module, and a hydrogen production module. The energy storage module includes a molten salt energy storage circuit, a liquid carbon dioxide energy storage circuit, a first heat exchanger 5, and a second heat exchanger 7. The renewable energy power generation device is connected to the molten salt energy storage circuit. The hot side of the first heat exchanger 5 is connected to the molten salt energy storage circuit, and the cold side of the first heat exchanger 5 is connected to the liquid carbon dioxide energy storage circuit. The hot side of the second heat exchanger 7 is also connected to the liquid carbon dioxide energy storage circuit. The hydrogen production module includes a heat transfer oil circuit and a methanol-to-hydrogen circuit. The methanol-to-hydrogen circuit includes a reactor 16 and a vaporizer 17. The heat transfer oil circuit is connected to the cold side of the second heat exchanger 7, the tube side of the reactor 16, and the hot side of the vaporizer 17.

[0025] According to an embodiment of the present invention, a hydrogen combined heat and power (CHP) liquid carbon dioxide energy storage system is provided. When the grid load demand is low, the electricity generated by the renewable energy power generation device cannot be connected to the grid, and the system is in the energy storage stage. The electrical energy is stored in the form of thermal energy through a molten salt energy storage circuit, and in the form of pressure energy through a liquid carbon dioxide energy storage circuit.

[0026] When the grid load is high, the system is in the energy release stage, the energy stored in the energy storage stage is converted into electric energy to provide for the grid, in this stage, the heat transfer oil circuit can absorb the heat energy released by the liquid carbon dioxide energy storage circuit through the second heat exchanger 7, it can be understood that the heat transfer oil circuit can transfer the heat contained in the turbine 6 exhaust to the heat transfer oil heat storage medium through the second heat exchanger 7, and provide energy for the gasification of the methanol raw material liquid and the hydrogen production reaction of the methanol reforming through the gasifier 17 and the reactor 16. Therefore, the hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application can utilize the heat energy of the turbine 6 outlet carbon dioxide working medium in the energy release stage to gasify the methanol raw material liquid and provide heat for the reactor 16 to maintain the hydrogen production reaction of the methanol reforming, so that the heat of the carbon dioxide working medium is reasonably and scientifically utilized, the energy cascade utilization is realized, and the production cost of hydrogen is greatly reduced, and the influence of the hydrogen production process on the environment is reduced.

[0027] On the other hand, the hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application can store the electric energy that cannot be utilized by the grid in the form of heat energy or other forms of energy, and convert the stored energy into electric energy when the grid needs it. Moreover, the hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application uses carbon dioxide as the working medium of the energy storage system, compared with other commonly used gases, carbon dioxide has higher density, and using carbon dioxide as the working medium will effectively reduce the size of each component of the energy storage system, shorten the construction period of the energy storage system, and reduce the investment cost of the energy storage system.

[0028] The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application stores the carbon dioxide working medium in liquid form, effectively reduces the volume of the container for storing the carbon dioxide working medium, greatly increases the energy storage density of the energy storage system, effectively reduces the investment cost of the working medium container and the land area occupied by the energy storage system, and reduces the construction cost of the energy storage system.

[0029] Optionally, the liquid carbon dioxide circuit comprises a turbine 6, a regenerator 8, a condenser 9, a low-pressure carbon dioxide storage tank 10, a carbon dioxide working fluid pump 11, a first cooler 12, and a high-pressure carbon dioxide storage tank 13, the outlet of the low-pressure carbon dioxide storage tank 10 is connected to the inlet of the carbon dioxide working fluid pump 11, the outlet of the carbon dioxide working fluid pump 11 is connected to the hot side inlet of the first cooler 12, the hot side outlet of the first cooler 12 is connected to the inlet of the high-pressure carbon dioxide storage tank 13, the outlet of the high-pressure carbon dioxide storage tank 13 is connected to the cold side inlet of the regenerator 8, the cold side outlet of the regenerator 8 is connected to the cold side inlet of the first heat exchanger 5, the cold side outlet of the first heat exchanger 5 is connected to the inlet of the turbine 6, the outlet of the turbine 6 is connected to the hot side inlet of the second heat exchanger 7, the hot side outlet of the second heat exchanger 7 is connected to the hot side inlet of the regenerator 8, the hot side outlet of the regenerator 8 is connected to the inlet of the condenser 9, and the outlet of the condenser 9 is connected to the inlet of the low-pressure carbon dioxide storage tank 10.

[0030] The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application uses the carbon dioxide working fluid pump 11 to increase the pressure of carbon dioxide, compared with the conventional scheme of using a compressor to increase the pressure of working fluid, the use of the pump to increase the pressure of working fluid effectively reduces the compression power consumption and effectively improves the efficiency of the energy storage system.

[0031] Optionally, the molten salt energy storage circuit comprises an electric heating boiler 2, a high-temperature molten salt storage tank 3, and a low-temperature molten salt storage tank 4, the renewable energy power generation device is used to supply power to the electric heating boiler 2, the outlet of the low-temperature molten salt storage tank 4 is connected to the inlet of the electric heating boiler 2, the outlet of the electric heating boiler 2 is connected to the inlet of the high-temperature molten salt storage tank 3, the outlet of the high-temperature molten salt storage tank 3 is connected to the hot side inlet of the first heat exchanger 5, and the hot side outlet of the first heat exchanger 5 is connected to the inlet of the low-temperature molten salt storage tank 4.

[0032] When the grid load demand is low, the electric energy generated by the renewable energy power generation device cannot be connected to the grid, and the system starts the energy storage process. The low-temperature molten salt in the low-temperature molten salt storage tank 4 enters the electric heating boiler 2, the electric heating boiler 2 uses the electric energy of the renewable energy power generation device to generate heat to heat the low-temperature molten salt, and the heated low-temperature molten salt becomes high-temperature molten salt and is stored in the high-temperature molten salt storage tank 3. At the same time, the electric energy of the renewable energy power generation device is used to drive the carbon dioxide working fluid pump 11 to pressurize the low-pressure liquid carbon dioxide in the low-pressure carbon dioxide storage tank 10 into high-pressure liquid carbon dioxide, and then the high-pressure liquid carbon dioxide enters the first cooler 12 and is stored in the high-pressure carbon dioxide storage tank 13 after being cooled, and the hot water generated by the first cooler 12 is used to provide hot water for residents. Through the above energy storage process, the electric energy of the renewable energy power generation device that cannot be connected to the grid is stored in the form of heat energy and pressure energy.

[0033] When the grid load demand is high, the system begins the energy release process. The high-pressure liquid carbon dioxide stored in the high-pressure carbon dioxide storage tank 13 enters the regenerator 8 and is heated to a gas state. The carbon dioxide working medium then enters the first heat exchanger 5 and is further heated by the high-temperature molten salt medium stored in the high-temperature molten salt storage tank 3, thereby increasing the superheat of the carbon dioxide working medium. The low-temperature molten salt medium that has completed the heat exchange process is stored in the low-temperature molten salt storage tank 4. The heated carbon dioxide working medium enters the turbine 6 to do work and drive the generator to generate electric energy. The carbon dioxide working medium then enters the second heat exchanger 7 from the outlet of the turbine 6. The low-temperature heat conducting oil stored in the low-temperature heat conducting oil storage tank 18 enters the second heat exchanger 7 and absorbs the heat energy of the carbon dioxide working medium to become high-temperature heat conducting oil stored in the high-temperature heat conducting oil storage tank 14. The carbon dioxide working medium that has completed the heat exchange enters the regenerator 8 for regenerative heating, heats and vaporizes the carbon dioxide entering the regenerator 8 from the high-pressure carbon dioxide storage tank 13, and then the carbon dioxide working medium that has completed the regenerative process is condensed into a liquid state by the condenser 9 and stored in the low-pressure carbon dioxide storage tank 10. Through the above energy release process, the thermal energy and pressure energy stored in the energy storage process are converted into electric energy to supply power to the grid.

[0034] Alternatively, the carbon dioxide working medium pump 11 is connected to a renewable energy power generation device, and the renewable energy power generation device can supply power to the carbon dioxide working medium pump 11. For example, the renewable energy power generation device is a wind farm 1. It can be understood that the electric heating boiler 2 and the carbon dioxide working medium pump 11 consume electric energy provided by the wind farm 1. The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application adopts the electric heating boiler 2 to store the off-grid electric energy of the wind farm in the form of heat energy in the molten salt heat storage medium, the heat storage temperature is high, and the turbine 6 inlet temperature of the energy storage system is effectively increased, thereby improving the efficiency of the energy storage system.

[0035] In some embodiments, the heat conducting oil circuit includes a high-temperature heat conducting oil storage tank 14, a heat conducting oil pump 15, and a low-temperature heat conducting oil storage tank 18. The outlet of the high-temperature heat conducting oil storage tank 14 is connected to the inlet of the heat conducting oil pump 15. The outlet of the heat conducting oil pump 15 is connected to the tube side inlet of the reactor 16. The tube side outlet of the reactor 16 is connected to the hot side inlet of the gasifier 17. The hot side outlet of the gasifier 17 is connected to the inlet of the low-temperature heat conducting oil storage tank 18. The outlet of the low-temperature heat conducting oil storage tank 18 is connected to the cold side inlet of the second heat exchanger 7. The cold side outlet of the second heat exchanger 7 is connected to the inlet of the high-temperature heat conducting oil tank. It can be understood that the hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application uses the heat conducting oil heat storage medium to store the turbine 6 exhaust heat, so that even if the energy storage system is not in the energy release state, the hydrogen production module still has a stable heat source for maintaining the methanol hydrogen production reaction.

[0036] Further, the methanol-to-hydrogen loop further comprises a feed device, a preheater 22, a second cooler 23, a gas-liquid separator 24, a pressure swing adsorber 25 and a hydrogen storage tank 26. The feed device is used to supply the methanol raw material, and the feed device comprises a desalted water storage tank 19, a methanol storage tank 20 and a methanol raw material liquid pump 21. The desalted water storage tank 19 is used to store desalted water, the methanol storage tank 20 is used to store methanol, and the desalted water in the desalted water storage tank is mixed with the methanol in the methanol storage tank in a certain proportion and then enters the methanol raw material liquid pump 21. The outlet of the methanol raw material liquid pump 21 is connected with the cold side inlet of the preheater 22.

[0037] The cold side outlet of the preheater 22 is connected with the cold side inlet of the gasifier 17, the cold side outlet of the gasifier 17 is connected with the shell side inlet of the reactor 16, the shell side outlet of the reactor 16 is connected with the hot side inlet of the preheater 22, the hot side outlet of the preheater 22 is connected with the hot side inlet of the second cooler 23, the hot side outlet of the second cooler 23 is connected with the inlet of the gas-liquid separator 24, the gas side outlet of the gas-liquid separator 24 is connected with the inlet of the pressure swing adsorber 25, and the outlet of the pressure swing adsorber 25 is connected with the inlet of the hydrogen storage tank 26. The shell side of the reactor 16 is filled with catalysts required for the methanol reforming reaction.

[0038] It can be understood that, in the hydrogen production process, the high-temperature heat conducting oil stored in the high-temperature heat conducting oil storage tank 14 enters the reactor 16 and the gasifier 17 under the action of the heat conducting oil pump 15, and the heat carried by the high-temperature heat conducting oil is used to maintain the methanol reforming reaction and gasify the methanol raw material liquid. Subsequently, the heat conducting oil after completing heat exchange is stored in the low-temperature heat conducting oil storage tank 18. The desalted water stored in the desalted water storage tank 19 is mixed with the methanol stored in the methanol storage tank 20 in a certain proportion to form the methanol raw material liquid, and then the methanol raw material liquid is pressurized by the methanol raw material liquid pump 21 and enters the preheater 22 for preheating. The preheated methanol raw material liquid enters the gasifier 17 and is heated by the heat conducting oil, and the gasified raw material enters the reactor 16 and is heated by the high-temperature heat conducting oil and undergoes the reforming reaction under the catalysis of the catalysts. The reaction product enters the preheater 22 to preheat the methanol raw material liquid, and then the reaction product enters the second cooler 23 and is cooled to enter the gas-liquid separator 24. In the gas-liquid separator 24, the gaseous product enters the pressure swing adsorber 25 to remove impurities therein, and pure hydrogen is obtained. Subsequently, the hydrogen is stored in the hydrogen storage tank 26, and the methanol reforming reaction is completed.

[0039] Optionally, the liquid side outlet of the gas-liquid separator 24 is connected with the inlet of the methanol raw material liquid pump 21, and the liquid material separated by the liquid side outlet of the gas-liquid separator 24 can be introduced into the inlet of the methanol raw material liquid pump 21, so that the liquid product is mixed with the methanol raw material liquid again to undergo the reforming reaction, thereby improving the utilization rate of the raw material and reducing the loss of the raw material.

[0040] In some embodiments, at least one of the condenser 9, the first cooler 12 and the second cooler 23 is connected with a domestic hot water circuit. For example, the condenser 9, the first cooler 12 and the second cooler 23 are all connected with the domestic hot water circuit to provide domestic hot water for residents or meet other daily life needs, realize energy cascade utilization, and reduce the heating and hot water cost of surrounding residents.

[0041] In summary, the hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiments of the present application has at least the following technical effects.

[0042] (1) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiments of the present application uses the heat energy of the carbon dioxide working medium at the outlet of the turbine 6 to absorb and store the heat energy to gasify the methanol raw material liquid and provide heat to the reactor 16 to maintain the methanol reforming reaction, so that the heat of the carbon dioxide working medium at the outlet of the turbine 6 is reasonably and scientifically utilized, energy cascade utilization is realized, the production cost of hydrogen is greatly reduced, and the environmental impact of the production process is greatly reduced.

[0043] (2) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiments of the present application uses the carbon dioxide working medium pump 11 to increase the pressure of the carbon dioxide, compared with the traditional scheme of using a compressor to increase the pressure of the working medium, the use of the pump to increase the pressure of the working medium effectively reduces the compression power consumption and effectively improves the efficiency of the energy storage system.

[0044] (3) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiments of the present application uses carbon dioxide as the working medium of the energy storage system, compared with other commonly used gases, carbon dioxide has higher density, and the use of carbon dioxide as the working medium will effectively reduce the size of each component of the energy storage system, shorten the construction period of the energy storage system, and reduce the investment cost of the energy storage system.

[0045] (4) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiments of the present application uses the electric heating boiler 2 to store the off-grid power of the wind farm 1 in the molten salt heat storage medium in the form of heat energy, the heat storage temperature is high, which effectively improves the inlet temperature of the turbine 6 of the energy storage system and improves the efficiency of the energy storage system.

[0046] (5) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiments of the present application stores the carbon dioxide working medium in a liquid state, effectively reduces the volume of the container for storing the carbon dioxide working medium, greatly increases the energy storage density of the energy storage system, effectively reduces the investment cost of the working medium container and the land area occupied by the energy storage system, and reduces the construction cost of the energy storage system.

[0047] (6) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application uses heat conducting oil as the heat storage medium to store the heat of the turbine 6 exhaust gas, so that even if the energy storage system is not in the energy releasing state, the hydrogen production module still has a stable heat source for maintaining the methanol hydrogen production reaction.

[0048] (7) The hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system of the embodiment of the present application uses the hot water generated by the cooler and condenser 9 to provide heating or meet other daily life needs for the surrounding residents in the form of domestic hot water, realizes energy cascade utilization, and reduces the heating and heat utilization costs of the surrounding residents.

[0049] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0050] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0051] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected or can communicate with each other; can be directly connected, or can be indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0052] In the present application, unless specifically stated and limited otherwise, a first feature "on" or "under" a second feature can be directly in contact with the second feature, or indirectly in contact with the second feature through an intermediate medium. Also, a first feature "over", "above" and "on top of" a second feature can be directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature "under", "below" and "underneath" a second feature can be directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0053] In the present application, the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" mean that a particular feature, structure, material or characteristic is included in at least one embodiment or example of the present application. Exemplary representations of the above terms in the present specification are not necessarily directed to the same embodiment or example. Also, the described specific features, structures, materials or characteristics can be combined in any suitable manner in any one or more embodiments or examples. In addition, different embodiments or examples described in the present specification and features of different embodiments or examples can be combined and combined by those skilled in the art without contradiction.

[0054] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary, and are not to be construed as limiting the present application, and changes, modifications, replacements and variations of the above embodiments made by those skilled in the art are within the scope of the present application.

Claims

1. A hydrogen-thermal-electricity tri-generation liquid carbon dioxide energy storage system, characterized in that, The renewable energy power generation device, the energy storage module and the hydrogen production module are connected in series. The energy storage module comprises a molten salt energy storage loop, a liquid carbon dioxide energy storage loop, a first heat exchanger and a second heat exchanger, the renewable energy power generation device is connected with the molten salt energy storage loop, the hot side of the first heat exchanger is connected with the molten salt energy storage loop, the cold side of the first heat exchanger is connected with the liquid carbon dioxide energy storage loop, and the hot side of the second heat exchanger is connected with the liquid carbon dioxide energy storage loop. The hydrogen production module comprises a heat conducting oil loop and a methanol hydrogen production loop, the methanol hydrogen production loop comprises a reactor and a gasifier, the heat conducting oil loop is connected with the cold side of the second heat exchanger, the tube side of the reactor and the hot side of the gasifier. The liquid carbon dioxide loop comprises a turbine, a regenerator, a condenser, a low-pressure carbon dioxide storage tank, a carbon dioxide working medium pump, a first cooler and a high-pressure carbon dioxide storage tank, The outlet of the low-pressure carbon dioxide storage tank is connected with the inlet of the carbon dioxide working medium pump, the outlet of the carbon dioxide working medium pump is connected with the hot side inlet of the first cooler, the hot side outlet of the first cooler is connected with the inlet of the high-pressure carbon dioxide storage tank, the outlet of the high-pressure carbon dioxide storage tank is connected with the cold side inlet of the regenerator, the cold side outlet of the regenerator is connected with the cold side inlet of the first heat exchanger, the cold side outlet of the first heat exchanger is connected with the inlet of the turbine, the outlet of the turbine is connected with the hot side inlet of the second heat exchanger, the hot side outlet of the second heat exchanger is connected with the hot side inlet of the regenerator, the hot side outlet of the regenerator is connected with the inlet of the condenser, and the outlet of the condenser is connected with the inlet of the low-pressure carbon dioxide storage tank. The high-pressure liquid carbon dioxide stored in the high-pressure carbon dioxide storage tank enters the regenerator and is heated into a gaseous state, then the carbon dioxide working medium enters the first heat exchanger and is further heated by the high-temperature molten salt medium stored in the high-temperature molten salt storage tank, the heated carbon dioxide working medium enters the turbine and does work to drive the generator to generate electric energy, then the carbon dioxide working medium from the turbine outlet enters the second heat exchanger, the low-temperature heat conducting oil stored in the low-temperature heat conducting oil storage tank enters the second heat exchanger and absorbs the heat energy of the carbon dioxide working medium to become high-temperature heat conducting oil which is stored in the high-temperature heat conducting oil storage tank.

2. The hydrogen-thermal-electricity trigeneration liquid carbon dioxide energy storage system according to claim 1, characterized in that, The carbon dioxide working medium pump is connected with the renewable energy power generation device, and the renewable energy power generation device can supply power to the carbon dioxide working medium pump. The renewable energy power generation device is a wind farm.

3. The hydrogen-thermal power tri-generation liquid carbon dioxide energy storage system according to claim 1, wherein The molten salt energy storage loop comprises an electric heating boiler, a high-temperature molten salt storage tank and a low-temperature molten salt storage tank, the renewable energy power generation device is used for supplying power to the electric heating boiler, the outlet of the low-temperature molten salt storage tank is connected with the inlet of the electric heating boiler, the outlet of the electric heating boiler is connected with the inlet of the high-temperature molten salt storage tank, the outlet of the high-temperature molten salt storage tank is connected with the inlet of the hot side of the first heat exchanger, and the hot side outlet of the first heat exchanger is connected with the inlet of the low-temperature molten salt storage tank.

4. The hydrogen-thermal power tri-generation liquid carbon dioxide energy storage system of claim 1, wherein, The heat conducting oil circuit comprises a high-temperature heat conducting oil storage tank, a heat conducting oil pump and a low-temperature heat conducting oil storage tank, the outlet of the high-temperature heat conducting oil storage tank is connected with the inlet of the heat conducting oil pump, the outlet of the heat conducting oil pump is connected with the tube side inlet of the reactor, the tube side outlet of the reactor is connected with the hot side inlet of the gasifier, the hot side outlet of the gasifier is connected with the inlet of the low-temperature heat conducting oil storage tank, the outlet of the low-temperature heat conducting oil storage tank is connected with the cold side inlet of the second heat exchanger, and the cold side outlet of the second heat exchanger is connected with the inlet of the high-temperature heat conducting oil storage tank.

5. A hydrogen-based thermo-electric trigeneration liquid carbon dioxide energy storage system according to claim 1, wherein, The methanol-to-hydrogen circuit further comprises a feeding device, a preheater, a second cooler, a gas-liquid separator, a pressure swing adsorber and a hydrogen storage tank, The feeding device is used for supplying methanol raw material liquid, the feeding device is connected with the cold side inlet of the preheater, the cold side outlet of the preheater is connected with the cold side inlet of the gasifier, the cold side outlet of the gasifier is connected with the shell side inlet of the reactor, the shell side outlet of the reactor is connected with the hot side inlet of the preheater, the hot side outlet of the preheater is connected with the hot side inlet of the second cooler, the hot side outlet of the second cooler is connected with the inlet of the gas-liquid separator, the gas side outlet of the gas-liquid separator is connected with the inlet of the pressure swing adsorber, and the outlet of the pressure swing adsorber is connected with the inlet of the hydrogen storage tank.

6. A hydrogen-based thermo-electric trigeneration liquid carbon dioxide energy storage system according to claim 5, wherein, The feeding device comprises a desalted water storage tank, a methanol storage tank and a methanol raw material liquid pump, the desalted water storage tank is used for storing desalted water, the methanol storage tank is used for storing methanol, and water in the desalted water storage tank and methanol in the methanol storage tank are mixed in a certain proportion and then enter the methanol raw material liquid pump, and the outlet of the methanol raw material liquid pump is connected with the cold side inlet of the preheater.

7. A hydrogen-based thermo-electric trigeneration liquid carbon dioxide energy storage system according to claim 6, wherein, The liquid side outlet of the gas-liquid separator is connected with the inlet of the methanol raw material liquid pump, and liquid substances separated by the liquid side outlet of the gas-liquid separator can enter the inlet of the methanol raw material liquid pump.

8. The hydrogen-thermal power tri-generation liquid carbon dioxide energy storage system of claim 6, wherein, At least one of the condenser, the first cooler and the second cooler is connected with a domestic hot water circuit.

9. A hydrogen-based thermo-electric trigeneration liquid carbon dioxide energy storage system according to any one of claims 1-8, wherein, The shell side of the reactor is filled with a catalyst required for methanol reforming to produce hydrogen.

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