Solar energy storage power generation system

Abstract

The invention discloses a solar energy storage power generation system. The system comprises a calcium carbonate storage tank; the calcium carbonate decomposition reactor is connected with the calcium carbonate storage tank and can decompose calcium carbonate into solid calcium oxide and gaseous carbon dioxide; the solar heat collection equipment is used for converting solar energy into heat energy; the compressor is connected with the calcium carbonate decomposition reactor and can compress gaseous carbon dioxide into liquid carbon dioxide; the liquid carbon dioxide storage tank is connected with the compressor; the calcium carbonate synthesis reactor is connected with the liquid carbon dioxide storage tank and can synthesize the solid calcium oxide and the liquid carbon dioxide into calcium carbonate and heat external nitrogen by utilizing heat generated in the synthesis process of the calcium carbonate; the expansion machine is connected with the calcium carbonate synthesis reactor and performs expansion power generation through heated nitrogen, unstable solar energy can be converted into energy in various stable forms to be stored, carbon dioxide is effectively utilized through internal circulation, and on-demand power generation is achieved on the basis of calcium-based thermal chemical reaction.

Description

Technical Field

[0001] This application belongs to the field of new energy storage technology, specifically relating to a solar energy storage power generation system. Background Technology

[0002] With the deepening implementation of the "dual carbon" target, the proportion of renewable energy, represented by solar energy, in the energy structure continues to increase. Solar power generation technology is mainly divided into two major routes: photovoltaic power generation and concentrated solar power (CSP). Among them, concentrated solar power (CSP) technology converts solar energy into high-temperature heat energy through a concentrating solar collector system, and then generates electricity through a thermal cycle. Its biggest advantage is that it can achieve time-shifted and stable, dispatchable power output by supporting a large-scale thermal storage system, effectively overcoming the intermittency and volatility problems of solar energy. It is a key technological support for building a future high-proportion renewable energy grid.

[0003] However, current mainstream solar thermal energy storage technologies, such as molten salt thermal energy storage, face challenges such as upper operating temperature limits, solidification risks, long-term corrosion, and thermal decay. Their single-medium energy storage density is gradually approaching its theoretical limit. Therefore, researchers have turned their attention to the more promising thermochemical energy storage (TCES). Among various options, calcium-based (CaCO3 / CaO) thermochemical energy storage cycles stand out due to the extremely low cost, wide availability, and non-toxic nature of their reactants (limestone, lime), and their extremely high energy storage density (theoretically reaching 3 GJ / m³). 3 (Far exceeding molten salt), it is considered one of the most promising long-term energy storage technologies. This technology utilizes the endothermic decomposition reaction of calcium carbonate (CaCO3) (CaCO3... The reaction (CaO + CO2 - ΔH) stores thermal energy during charging and releases it during exothermic reactions through the recombination of calcium oxide (CaO) and carbon dioxide (CO2). Its reaction temperature range (800-900℃) closely matches the output temperature of next-generation high-temperature concentrating solar collectors, making it an ideal pathway for achieving efficient solar energy conversion and long-term storage.

[0004] However, the commercial application of calcium-based energy storage faces a core bottleneck: the efficient separation and storage of carbon dioxide, a byproduct of the reaction. If the large amount of carbon dioxide gas produced by the decomposition reaction is not properly disposed of, the system will not be able to operate stably. The traditional approach is to construct large-scale atmospheric pressure carbon dioxide storage facilities, but this not only results in a huge land area and high civil engineering costs, but also poses a risk of gas leakage, severely restricting the application of this technology in areas lacking natural geological reservoirs.

[0005] Meanwhile, another large-scale physical energy storage technology, Liquid CO2 Energy Storage (LCES), has developed rapidly in recent years. LCES is based on the characteristics of high critical temperature (31.1℃) and easy liquefaction of carbon dioxide. The gaseous carbon dioxide is converted into liquid carbon dioxide by compression and cooling for storage. LCES has high energy storage density, and the liquid storage tank can operate at normal temperature and pressure, and the cost is much lower than that of the same scale high-pressure gaseous storage tank. However, LCES also faces a "closed loop" problem: during the discharging process, the carbon dioxide expands to do work in the turbine and becomes gaseous at low temperature and low pressure again. A large low-pressure gas storage unit is needed to accommodate the circulating working medium, resulting in a large system footprint and reduced efficiency. SUMMARY

[0006] The purpose of the present application is to provide a solar energy storage power generation system that converts unstable solar energy into multiple stable forms of energy for storage, effectively utilizes carbon dioxide through internal circulation, and realizes on-demand power generation based on calcium-based thermochemical reactions, effectively solving the problems of gas storage dependence, efficiency bottleneck, and high cost faced by single energy storage technology.

[0007] To achieve the above purpose, the present application provides a solar energy storage power generation system, which comprises: a calcium carbonate storage tank for storing calcium carbonate; a calcium carbonate decomposition reactor connected to the output end of the calcium carbonate storage tank and used for decomposing calcium carbonate into solid calcium oxide and gaseous carbon dioxide; a solar heat collecting device for converting solar energy into heat energy required for decomposing calcium carbonate in the calcium carbonate decomposition reactor; a compressor with a gas input end connected to the output end of the calcium carbonate decomposition reactor and used for compressing gaseous carbon dioxide into liquid carbon dioxide; a liquid carbon dioxide storage tank connected to the fluid output end of the compressor and used for storing liquid carbon dioxide from the fluid output end; a calcium carbonate synthesis reactor connected to the liquid carbon dioxide storage tank, used for synthesizing calcium carbonate from solid calcium oxide and liquid carbon dioxide from the liquid carbon dioxide storage tank, and heating external nitrogen gas using the heat generated during the synthesis of calcium carbonate; an expander connected to the output end of the calcium carbonate synthesis reactor and used for expanding and generating electricity using the heated nitrogen gas.

[0008] In an embodiment of the present application, the solid calcium oxide is powdered calcium oxide, and the solar energy storage power generation system further comprises: a first separator, an input end of the first separator being connected with the output end of the calcium carbonate decomposition reactor, a first output end of the first separator being connected with the input end of the compressor, for separating the first fluid mixture from the calcium carbonate decomposition reactor into solid calcium oxide and gaseous carbon dioxide and nitrogen, wherein the first fluid mixture is formed by mixing the solid calcium oxide, the gaseous carbon dioxide and the nitrogen.

[0009] In the embodiment of the present application, the compressor comprises a compression heat output end and an electric energy input end, the compression heat output end being used for outputting compression heat generated when the gaseous carbon dioxide is compressed into liquid carbon dioxide, and the solar energy storage power generation system further comprises: a thermoelectric power generation device, an input end of the thermoelectric power generation device being connected with the compression heat output end and being used for generating electric energy by using the compression heat, and an output end of the thermoelectric power generation device being connected with the electric energy input end and being used for transmitting the electric energy to the electric energy input end.

[0010] In the embodiment of the present application, the solar energy storage power generation system further comprises: a first nitrogen conveying pipeline, an output end of the first nitrogen conveying pipeline being connected with the first input end of the calcium carbonate storage tank and being used for conveying nitrogen into the calcium carbonate storage tank; a second separator, an input end of the second separator being connected with the fluid output end of the compressor and being used for inputting a second fluid mixture, the second fluid mixture being formed by mixing the liquid carbon dioxide and the nitrogen flowing through the calcium carbonate storage tank, the first separator and the compressor in sequence, a first output end of the second separator being connected with the liquid carbon dioxide storage tank and being used for outputting the liquid carbon dioxide separated from the second fluid mixture, and a second output end of the second separator being connected with the input end of the first nitrogen conveying pipeline and being used for outputting the nitrogen separated from the second fluid mixture.

[0011] In the embodiment of the present application, the solar energy storage power generation system further comprises: a first circulating fan, arranged on the first nitrogen conveying pipeline and used for accelerating the nitrogen output from the second output end of the second separator to flow to the first input end of the calcium carbonate storage tank.

[0012] In the embodiment of the present application, the solar energy storage power generation system further comprises: a carbon dioxide booster pump, arranged between the liquid carbon dioxide storage tank and the calcium carbonate synthesis reactor and used for pressurizing the liquid carbon dioxide to enter the calcium carbonate synthesis reactor.

[0013] In the embodiment of the present application, the solar energy storage power generation system further comprises: a calcium oxide storage tank, a first input end of the calcium oxide storage tank being connected with the second output end of the first separator, and an output end of the calcium oxide storage tank being connected with the second input end of the calcium carbonate synthesis reactor, for storing the solid calcium oxide separated by the first separator.

[0014] In the embodiments of the present application, the solar energy storage power generation system further comprises: a third separator, an input end of the third separator being connected with an output end of the calcium carbonate synthesis reactor, a first output end of the third separator being connected with an input end of the expander, the third separator being used for separating the third fluid mixture from the calcium carbonate synthesis reactor into calcium carbonate and heated nitrogen, the third fluid mixture being formed by mixing calcium carbonate and heated nitrogen.

[0015] In the embodiments of the present application, a second output end of the third separator is connected with a second input end of the calcium carbonate storage tank and is used for conveying the calcium carbonate separated from the third fluid mixture to the calcium carbonate storage tank.

[0016] In the embodiments of the present application, the solar energy storage power generation system further comprises: a second nitrogen conveying pipeline, an input end of the second nitrogen conveying pipeline being connected with an output end of the expander, an output end of the second nitrogen conveying pipeline being connected with a second input end of the calcium oxide storage tank, and the second nitrogen conveying pipeline being used for conveying the nitrogen output from the expander to the calcium oxide storage tank; a second circulating fan, which is arranged on the second nitrogen conveying pipeline and is used for accelerating the nitrogen output from the expander to flow to the second input end of the calcium oxide storage tank.

[0017] According to the above technical solution, the solar energy storage power generation system comprises: a calcium carbonate storage tank, which is used for storing calcium carbonate; a calcium carbonate decomposition reactor, which is connected with an output end of the calcium carbonate storage tank and is used for decomposing the calcium carbonate into solid calcium oxide and gaseous carbon dioxide; a solar heat collecting device, which is used for converting solar energy into heat energy required for decomposing the calcium carbonate by the calcium carbonate decomposition reactor; a compressor, a gas input end of the compressor being connected with an output end of the calcium carbonate decomposition reactor and the compressor being used for compressing the gaseous carbon dioxide into liquid carbon dioxide; a liquid carbon dioxide storage tank, which is connected with a fluid output end of the compressor and is used for storing the liquid carbon dioxide from the fluid output end; a calcium carbonate synthesis reactor, which is connected with the liquid carbon dioxide storage tank and is used for synthesizing the calcium carbonate by combining the solid calcium oxide and the liquid carbon dioxide from the liquid carbon dioxide storage tank and heating external nitrogen by using heat generated in the synthesis process of the calcium carbonate; and an expander, which is connected with an output end of the calcium carbonate synthesis reactor and is used for generating power by expanding the heated nitrogen. The solar energy storage power generation system integrates the solar heat collecting device, the energy storage loop based on the calcium-based thermochemical reaction and the liquid carbon dioxide energy storage device, not only converts unstable solar energy into stable and controllable chemical energy and internal energy, realizes long-time and large-capacity energy storage and controllable power generation, but also greatly improves the utilization efficiency of carbon dioxide through internal circulation.

[0018] Other features and advantages of the embodiments of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings are included to provide a further understanding of the embodiments of the application, and are incorporated in and constitute a part of this specification, illustrate embodiments of the application, and together with the description serve to explain the principles of the application. The drawings are provided to illustrate the structures described herein and are not necessarily drawn to scale. In the drawings: Figure 1 A schematic diagram of the system of the present application.

[0020] BRIEF DESCRIPTION OF DRAWINGS 1 - calcium carbonate storage tank; 2 - calcium carbonate decomposition reactor; 3 - first circulating fan; 4 - first separator; 5 - compressor; 6 - thermoelectric generator; 7 - second separator; 8 - liquid carbon dioxide storage tank; 9 - carbon dioxide booster pump; 10 - calcium carbonate synthesis reactor; 11 - calcium oxide storage tank; 12 - third separator; 13 - second circulating fan; 14 - expander; 15 - solar heat collecting device; 16 - first nitrogen conveying pipeline; 17 - second nitrogen conveying pipeline; 18 - first fluid conveying pipeline; 19 - liquid carbon dioxide conveying pipeline; 20 - calcium carbonate conveying pipeline; 21 - calcium oxide conveying pipeline; 22 - second fluid conveying pipeline; 23 - third nitrogen conveying pipeline. DETAILED DESCRIPTION

[0021] The specific embodiments of the present application will be described in detail below with reference to the drawings. It should be understood that the specific embodiments described herein are merely illustrative and explanatory and are not intended to limit the application.

[0022] A solar energy storage power generation system is provided in the embodiments of the present application, as shown in FIG. 1, which comprises: a calcium carbonate storage tank 1 for storing calcium carbonate; a calcium carbonate decomposition reactor 2 connected to the output end of the calcium carbonate storage tank 1 and used for decomposing calcium carbonate into solid calcium oxide and gaseous carbon dioxide; a solar heat collecting device 15 for converting solar energy into heat energy required for decomposing calcium carbonate in the calcium carbonate decomposition reactor 2; a compressor 5, the gas input end of which is connected to the output end of the calcium carbonate decomposition reactor 2 and used for compressing gaseous carbon dioxide into liquid carbon dioxide; a liquid carbon dioxide storage tank 8 connected to the fluid output end of the compressor 5 and used for storing liquid carbon dioxide from the fluid output end; a calcium carbonate synthesis reactor 10 connected to the liquid carbon dioxide storage tank 8 and used for synthesizing calcium carbonate from solid calcium oxide and liquid carbon dioxide from the liquid carbon dioxide storage tank 8 and heating external nitrogen gas with the heat generated in the synthesis process of calcium carbonate; and an expander 14 connected to the output end of the calcium carbonate synthesis reactor 10 and used for generating electricity by expanding the heated nitrogen gas. Figure 1 A solar energy storage power generation system is provided in the embodiments of the present application, as shown in FIG. 1, which comprises: a calcium carbonate storage tank 1 for storing calcium carbonate; a calcium carbonate decomposition reactor 2 connected to the output end of the calcium carbonate storage tank 1 and used for decomposing calcium carbonate into solid calcium oxide and gaseous carbon dioxide; a solar heat collecting device 15 for converting solar energy into heat energy required for decomposing calcium carbonate in the calcium carbonate decomposition reactor 2; a compressor 5, the gas input end of which is connected to the output end of the calcium carbonate decomposition reactor 2 and used for compressing gaseous carbon dioxide into liquid carbon dioxide; a liquid carbon dioxide storage tank 8 connected to the fluid output end of the compressor 5 and used for storing liquid carbon dioxide from the fluid output end; a calcium carbonate synthesis reactor 10 connected to the liquid carbon dioxide storage tank 8 and used for synthesizing calcium carbonate from solid calcium oxide and liquid carbon dioxide from the liquid carbon dioxide storage tank 8 and heating external nitrogen gas with the heat generated in the synthesis process of calcium carbonate; and an expander 14 connected to the output end of the calcium carbonate synthesis reactor 10 and used for generating electricity by expanding the heated nitrogen gas.

[0023] Specifically, the inner cavity of the calcium carbonate storage tank 1 is pre-stored with calcium carbonate (in the form of powder in the present embodiment), during the energy storage period of the solar energy storage power generation system, the calcium carbonate flows out of the output end of the calcium carbonate storage tank 1 and enters the inner cavity of the calcium carbonate decomposition reactor 2 through the input end of the calcium carbonate decomposition reactor 2, the calcium carbonate decomposition reactor 2 uses the heat energy converted from the sunlight energy by the solar heat collecting device to decompose the calcium carbonate into solid calcium oxide (in the form of powder in the present embodiment) and gaseous carbon dioxide, the decomposed gaseous carbon dioxide flows out of the output end of the calcium carbonate decomposition reactor 2 and enters the compressor 5 through the gas input end of the compressor 5 to be compressed, the compressor 5 pressurizes the gaseous carbon dioxide to a supercritical state and cools the supercritical carbon dioxide at room temperature, so that the gaseous carbon dioxide is converted into liquid carbon dioxide, the liquid carbon dioxide enters the inner cavity of the liquid carbon dioxide storage tank 8 through the fluid output end of the compressor 5 and the input end of the liquid carbon dioxide storage tank 8. During the energy release period of the solar energy storage power generation system, the liquid carbon dioxide in the liquid carbon dioxide storage tank 8 enters the inside of the calcium carbonate synthesis reactor 10 through the output end of the liquid carbon dioxide storage tank 8 and the first input end of the calcium carbonate synthesis reactor 10, and reacts with the solid calcium oxide in the inside of the calcium carbonate synthesis reactor 10, during the above-mentioned synthesis reaction, external nitrogen gas enters the inside of the calcium carbonate synthesis reactor 10, the synthesis reaction produces a large amount of heat energy, the heat energy heats the nitrogen gas entering the inside of the calcium carbonate synthesis reactor 10, the heated nitrogen gas is high-temperature nitrogen gas, the temperature range of the high-temperature nitrogen gas is 400-500°C; then the high-temperature nitrogen gas (i.e. the heated nitrogen gas) enters the inside of the expander 14 through the output end of the calcium carbonate synthesis reactor 10 and the input end of the expander 14 and drives the expander 14 to do work and generate electricity.

[0024] The solar energy storage power generation system in the present embodiment converts the sunlight energy into the heat energy required for the calcium carbonate decomposition reactor 2 to decompose calcium carbonate, the gaseous carbon dioxide after the decomposition of calcium carbonate is compressed by the compressor 5 to form liquid carbon dioxide and is stored by the liquid carbon dioxide storage tank 8, the liquid carbon dioxide synthesizes solid calcium carbonate with calcium oxide in the calcium carbonate synthesis reactor 10 and produces heat, the heat heats external nitrogen gas, so that the expander 14 expands to generate electricity by using the heated nitrogen gas, not only the unstable sunlight energy is converted into stable and controllable chemical energy and internal energy, realizing long-time and large-capacity energy storage and controllable electricity generation, but also the utilization efficiency of carbon dioxide and calcium carbonate is greatly improved through internal circulation.

[0025] In one embodiment of the present application, the solid calcium oxide is powdered calcium oxide, and the solar energy storage power generation system further comprises a first separator 4, an input end of the first separator 4 being connected with an output end of the calcium carbonate decomposition reactor 2, a first output end of the first separator 4 being connected with an input end of the compressor 5, and the first separator 4 being configured to separate the first fluid mixture from the calcium carbonate decomposition reactor 2 into the solid calcium oxide and the gaseous carbon dioxide and nitrogen, wherein the first fluid mixture is formed by mixing the solid calcium oxide, the gaseous carbon dioxide and the nitrogen.

[0026] Specifically, when the solar energy storage power generation system in the embodiment is in operation, the high-speed flowing nitrogen enters the calcium carbonate storage tank 1 through the first input end of the calcium carbonate storage tank 1 and drives the calcium carbonate in the inner cavity of the calcium carbonate storage tank 1 to flow outwards to the calcium carbonate decomposition reactor 2, the solid calcium oxide, the gaseous carbon dioxide and the nitrogen formed after the calcium carbonate decomposition reactor 2 decomposes the calcium carbonate together form the first fluid mixture and flow out from the output end of the calcium carbonate decomposition reactor 2, then enter the first separator 4 through the input end of the first separator 4, the first separator 4 separates the first fluid mixture, the first separator 4 separates the gaseous carbon dioxide and the nitrogen which are gaseous and the solid calcium oxide, the gaseous carbon dioxide and the nitrogen which are gaseous enter the inside of the compressor 5 through the fluid output end of the first separator 4 and the input end of the compressor 5.

[0027] In one embodiment of the present application, the compressor 5 comprises a compression heat output end and an electric energy input end, the compression heat output end being configured to output the compression heat generated when the gaseous carbon dioxide is compressed into liquid carbon dioxide, and the solar energy storage power generation system further comprises a thermoelectric power generation device 6, an input end of the thermoelectric power generation device 6 being connected with the compression heat output end and being configured to generate electric energy by using the compression heat, and an output end of the thermoelectric power generation device 6 being connected with the electric energy input end and being configured to deliver the electric energy to the electric energy input end.

[0028] Specifically, after the gaseous carbon dioxide and the nitrogen from the fluid output end of the first separator 4 enter the inside of the compressor 5 through the gas input end of the compressor 5, the compressor 5 compresses the gaseous carbon dioxide and the nitrogen and generates compression heat, the compression heat enters the inside of the thermoelectric power generation device 6 through the compression heat output end of the compressor 5 and the input end of the thermoelectric power generation device 6 (the thermoelectric power generation device 6 in the embodiment can be selected as a thermoelectric generator), the thermoelectric power generation device 6 generates electric energy by using the compression heat through an organic Rankine cycle (or a steam Rankine cycle, etc.), and the electric energy generated by the thermoelectric power generation device 6 is delivered to the compressor 5 through the output end of the thermoelectric power generation device 6 and the electric energy input end of the compressor 5, so as to supplement the electric energy consumption of the compressor 5 in the compression process, thereby realizing the recycling of part of the energy and reducing the energy loss in the operation process of the solar energy storage power generation system.

[0029] In one embodiment of the present application, the solar energy storage power generation system further comprises: a first nitrogen conveying pipeline 16, an output end of the first nitrogen conveying pipeline 16 being connected with a first input end of the calcium carbonate storage tank 1 and used for conveying nitrogen into the calcium carbonate storage tank 1; and a second separator 7, an input end of the second separator 7 being connected with a fluid output end of the compressor 5 and used for inputting a second fluid mixture, the second fluid mixture being formed by liquid carbon dioxide and nitrogen sequentially flowing through the calcium carbonate storage tank 1, the first separator 4 and the compressor 5, a first output end of the second separator 7 being connected with the liquid carbon dioxide storage tank 8 and used for outputting the liquid carbon dioxide separated from the second fluid mixture, and a second output end of the second separator 7 being connected with an input end of the first nitrogen conveying pipeline 16 and used for outputting the nitrogen separated from the second fluid mixture.

[0030] Specifically, the inside of the first nitrogen conveying pipeline 16 is pre-filled with nitrogen for recycling by the solar energy storage power generation system. During the energy storage period of the solar energy storage power generation system, the gaseous carbon dioxide separated from the first separator 4 and the nitrogen enter the compressor 5 through the gas input end of the compressor 5, and then are converted into the second fluid mixture formed by liquid carbon dioxide and nitrogen sequentially flowing through the calcium carbonate storage tank 1, the first separator 4 and the compressor 5 after being compressed by the compressor 5. The second fluid mixture enters the inside of the second separator 7 through the fluid output end of the compressor 5 and the input end of the second separator 7. The second separator 7 separates the liquid carbon dioxide and the nitrogen in the second fluid mixture. The separated liquid carbon dioxide enters the inner cavity of the liquid carbon dioxide storage tank 8 through the first output end of the second separator 7 and the input end of the liquid carbon dioxide storage tank 8. The separated nitrogen enters the first nitrogen conveying pipeline 16 through the second output end of the second separator 7 and the input end of the first nitrogen conveying pipeline 16. During the energy storage period of the solar energy storage power generation system, the nitrogen in the first nitrogen conveying pipeline 16 is conveyed to the inner cavity of the calcium carbonate storage tank 1 through the output end of the first nitrogen conveying pipeline 16 and the first input end of the calcium carbonate storage tank 1.

[0031] Further, the solar energy storage power generation system in the present embodiment further comprises a first fluid conveying pipeline 18, an input end of the first fluid conveying pipeline 18 being connected with an output end of the calcium carbonate storage tank 1, and an output end of the first fluid conveying pipeline 18 being connected with an input end of the second separator 7. The calcium carbonate decomposition reactor 2, the first separator 4 and the compressor 5 are all arranged on the first fluid conveying pipeline 18 and are sequentially distributed between the calcium carbonate storage tank 1 and the second separator 7. The nitrogen entering the calcium carbonate storage tank 1 is conveyed to the inside of the second separator 7 together with the liquid carbon dioxide after passing through the first fluid conveying pipeline 18, and then is separated into the separate liquid carbon dioxide and the separate nitrogen by the second separator 7.

[0032] In one embodiment of the present application, the solar energy storage power generation system further comprises: a first circulating fan 3 arranged on the first nitrogen conveying pipeline 16 and used for accelerating the nitrogen flowing from the second output end of the second separator 7 to the first input end of the calcium carbonate storage tank 1.

[0033] Specifically, during the energy storage period of the solar energy storage power generation system, the first circulating fan 3 arranged on the first nitrogen conveying pipeline 16 provides power to generate airflow of the nitrogen in the first nitrogen conveying pipeline 16, drives the nitrogen in the first nitrogen conveying pipeline 16 to accelerate to the first input end of the calcium carbonate storage tank 1, so that the high-speed flowing nitrogen blows the calcium carbonate out of the inner cavity of the calcium carbonate storage tank 1 and into the inside of the calcium carbonate decomposition reactor 2. Through the above steps, the solar energy storage power generation system converts the solar light energy and the electric energy into chemical energy and internal energy storage of calcium oxide and liquid carbon dioxide, and recovers and converts part of the heat energy into electric energy.

[0034] In one embodiment of the present application, the solar energy storage power generation system further comprises: a carbon dioxide booster pump 9 arranged between the liquid carbon dioxide storage tank 8 and the calcium carbonate synthesis reactor 10 and used for pressurizing the liquid carbon dioxide to enter the calcium carbonate synthesis reactor 10.

[0035] Specifically, during the energy release period of the solar energy storage power generation system, the liquid carbon dioxide stored in the inner cavity of the liquid carbon dioxide storage tank 8 enters the inside of the carbon dioxide booster pump 9 through the output end of the liquid carbon dioxide storage tank 8 and the input end of the carbon dioxide booster pump 9, the liquid carbon dioxide is pressurized by the carbon dioxide booster pump 9 to form high-pressure liquid carbon dioxide (or supercritical carbon dioxide), and the high-pressure liquid carbon dioxide (or supercritical carbon dioxide) enters the calcium carbonate synthesis reactor 10 through the output end of the carbon dioxide booster pump 9 and the first input end of the calcium carbonate synthesis reactor 10.

[0036] Further, the solar energy storage power generation system in the embodiment further comprises a liquid carbon dioxide conveying pipeline 19 for conveying the liquid carbon dioxide, the input end of the liquid carbon dioxide conveying pipeline 19 is connected with the first output end of the second separator 7, the output end of the liquid carbon dioxide conveying pipeline 19 is connected with the first input end of the calcium carbonate synthesis reactor 10, and the carbon dioxide booster pump 9 is arranged on the liquid carbon dioxide conveying pipeline 19 and distributed between the second separator 7 and the calcium carbonate synthesis reactor 10.

[0037] In one embodiment of the present application, the solar energy storage power generation system further comprises: a calcium oxide storage tank 11, the first input end of the calcium oxide storage tank 11 is connected with the second output end of the first separator 4, the output end of the calcium oxide storage tank 11 is connected with the second input end of the calcium carbonate synthesis reactor 10, and the calcium oxide storage tank 11 is used for storing the solid calcium oxide separated by the first separator 4.

[0038] Specifically, the solid calcium oxide separated from the first separator 4 is stored in the calcium oxide storage tank 11, and in the energy releasing process of the solar energy storage power generation system, the solid calcium oxide in the calcium oxide storage tank 11 enters the inside of the calcium carbonate synthesis reactor 10 through the second input end of the calcium carbonate synthesis reactor 10, and the solid calcium oxide and the high-pressure liquid carbon dioxide (or supercritical carbon dioxide) in the calcium carbonate synthesis reactor 10 generate the calcium carbonate through a synthesis reaction.

[0039] Further, the solar energy storage power generation system in the embodiment further comprises a calcium oxide conveying pipeline 21 for conveying the solid calcium oxide, an input end of the calcium oxide conveying pipeline 21 is connected with the first output end of the first separator 4, an output end of the calcium oxide conveying pipeline 21 is connected with the second input end of the calcium carbonate synthesis reactor 10, and the calcium oxide storage tank 11 is arranged on the calcium oxide conveying pipeline 21 and is distributed between the first separator 4 and the calcium carbonate synthesis reactor 10.

[0040] In an embodiment of the present application, the solar energy storage power generation system further comprises a third separator 12, an input end of the third separator 12 is connected with an output end of the calcium carbonate synthesis reactor 10, and a first output end of the third separator 12 is connected with an input end of the expander 14, and the third separator 12 is used for separating the third fluid mixture from the calcium carbonate synthesis reactor 10 into the calcium carbonate and the heated nitrogen, and the third fluid mixture is formed by mixing the calcium carbonate and the heated nitrogen.

[0041] Specifically, the solar energy storage power generation system in the embodiment further comprises a second fluid conveying pipeline 22 for conveying the third fluid mixture, an input end of the second fluid conveying pipeline 22 is connected with an output end of the calcium carbonate synthesis reactor 10, and an output end of the second fluid conveying pipeline 22 is connected with an input end of the third separator 12, and the calcium carbonate and the high-temperature nitrogen (i.e. the third fluid mixture) from the calcium carbonate synthesis reactor 10 enter the inside of the third separator 12 through the output end of the calcium carbonate synthesis reactor 10, the second fluid conveying pipeline 22 and the input end of the third separator 12, and the third separator 12 separates the third fluid mixture into the calcium carbonate and the high-temperature nitrogen.

[0042] Further, the solar energy storage power generation system in the embodiment further comprises a third nitrogen conveying pipeline 23 for conveying the high-temperature nitrogen, an input end of the third nitrogen conveying pipeline 23 is connected with a first output end of the third separator 12, and an output end of the third nitrogen conveying pipeline 23 is connected with an input end of the expander 14, and the high-temperature nitrogen separated from the third fluid mixture enters the inside of the expander 14 through the first output end of the third separator 12, the third nitrogen conveying pipeline 23 and the input end of the expander 14, so that the expander 14 generates electricity by expanding the high-temperature nitrogen.

[0043] In an embodiment of the present application, the second output end of the third separator 12 is connected with the second input end of the calcium carbonate storage tank 1 and used to transport the calcium carbonate separated from the third fluid mixture to the calcium carbonate storage tank 1.

[0044] Specifically, the solar energy storage power generation system in the embodiment further comprises a calcium carbonate delivery pipeline 20, the input end of the calcium carbonate delivery pipeline 20 is connected with the second output end of the third separator 12, the output end of the calcium carbonate delivery pipeline 20 is connected with the second input end of the calcium carbonate storage tank 1, and the calcium carbonate separated from the third separator 12 returns to the inner cavity of the calcium carbonate storage tank 1 through the calcium carbonate delivery pipeline 20.

[0045] Further, the solar energy storage power generation system in the embodiment further comprises a calcium oxide delivery pipeline 21 used to transport the solid calcium oxide, the input end of the calcium oxide delivery pipeline 21 is connected with the first output end of the first separator 4, the output end of the calcium oxide delivery pipeline 21 is connected with the second input end of the calcium carbonate synthesis reactor 10, and the calcium oxide storage tank 11 is arranged on the calcium oxide delivery pipeline 21 and distributed between the first separator 4 and the calcium carbonate synthesis reactor 10. In this way, the solar energy storage power generation system utilizes the energy storage circulation loop based on the calcium-based thermochemical reaction to recycle the calcium carbonate, thereby improving the utilization rate of the calcium carbonate.

[0046] In an embodiment of the present application, the solar energy storage power generation system further comprises a second nitrogen delivery pipeline 17, the input end of the second nitrogen delivery pipeline 17 is connected with the output end of the expander 14, the output end of the second nitrogen delivery pipeline 17 is connected with the second input end of the calcium oxide storage tank 11, and used to deliver the nitrogen output from the expander 14 to the calcium oxide storage tank 11; and a second circulating fan 13 arranged on the second nitrogen delivery pipeline and used to accelerate the nitrogen output from the expander 14 to flow to the second input end of the calcium oxide storage tank 11.

[0047] Specifically, the inside of the second nitrogen delivery pipeline 17 is pre-filled with nitrogen for recycling by the solar energy storage power generation system. During the energy release period of the solar energy storage power generation system, the high-temperature nitrogen separated from the third separator 12 enters the inside of the expander 14 through the first output end of the third separator 12 and the input end of the expander 14, pushes the expander 14 to work and generate electric energy output, and the high-temperature nitrogen restores to normal temperature after the expansion of the expander 14 and enters the second nitrogen delivery pipeline 17 through the output end of the expander 14 and the input end of the second nitrogen delivery pipeline 17. The second circulating fan 13 provides power to make the nitrogen in the second nitrogen delivery pipeline 17 generate airflow, drives the nitrogen in the second nitrogen delivery pipeline 17 to accelerate to flow to the second input end of the calcium oxide storage tank 11, so that the high-speed flowing nitrogen blows the calcium oxide out of the inner cavity of the calcium oxide storage tank 11 and into the inside of the calcium carbonate synthesis reactor 10.

[0048] Through the above steps, the solar energy storage power generation system completes the conversion of chemical energy and internal energy of calcium carbonate and carbon dioxide into electric energy.

[0049] In the description of the present application, it needs to be understood that the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. 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.

[0050] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and other terms should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrated; it can be mechanical connection, or electrical connection or communication with each other; it can be directly connected, or indirectly connected through an intermediate medium, it 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.

[0051] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0052] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A solar energy storage power generation system, characterized by, The solar energy storage power generation system comprises: a calcium carbonate storage tank (1) for storing calcium carbonate; a calcium carbonate decomposition reactor (2) connected with an output end of the calcium carbonate storage tank (1) and used for decomposing the calcium carbonate into solid calcium oxide and gaseous carbon dioxide; a solar heat collecting device (15) for converting solar energy into heat energy required by the calcium carbonate decomposition reactor (2) for decomposing the calcium carbonate; a compressor (5) with a gas input end connected with an output end of the calcium carbonate decomposition reactor (2) and used for compressing the gaseous carbon dioxide into liquid carbon dioxide; a liquid carbon dioxide storage tank (8) connected with a fluid output end of the compressor (5) and used for storing the liquid carbon dioxide from the fluid output end; a calcium carbonate synthesis reactor (10) connected with the liquid carbon dioxide storage tank (8) and used for synthesizing the solid calcium oxide and the liquid carbon dioxide from the liquid carbon dioxide storage tank (8) into calcium carbonate and heating external nitrogen gas by using heat generated in the synthesis process of the calcium carbonate; an expander (14) connected with an output end of the calcium carbonate synthesis reactor (10) and used for generating power by expanding the heated nitrogen gas.

2. The solar energy power generation system of claim 1, wherein, The calcium oxide is in a powder form, and the solar energy storage power generation system further comprises: a first separator (4) with an input end connected with an output end of the calcium carbonate decomposition reactor (2) and a first output end connected with an input end of the compressor (5) and used for separating a first fluid mixture from the calcium carbonate decomposition reactor (2) into the solid calcium oxide, the gaseous carbon dioxide and the nitrogen gas, wherein the first fluid mixture is formed by mixing the solid calcium oxide, the gaseous carbon dioxide and the nitrogen gas.

3. The solar energy power generation system of claim 1, wherein, The compressor (5) comprises a compression heat output end and an electric energy input end, the compression heat output end is used for outputting compression heat generated by compressing the gaseous carbon dioxide into the liquid carbon dioxide, and the solar energy storage power generation system further comprises: a thermoelectric power generation device (6) with an input end connected with the compression heat output end and used for generating power by using the compression heat and generating electric energy, and an output end connected with the electric energy input end and used for delivering the electric energy to the electric energy input end.

4. The solar energy power generation system of claim 2, wherein, The solar energy storage power generation system further comprises: a first nitrogen gas conveying pipeline (16) with an output end connected with a first input end of the calcium carbonate storage tank (1) and used for conveying nitrogen gas to the calcium carbonate storage tank (1); A second separator (7) is connected with the fluid output end of the compressor (5) and used for inputting a second fluid mixture, which is formed by the liquid carbon dioxide and the nitrogen gas sequentially flowing through the calcium carbonate storage tank (1), the first separator (4) and the compressor (5). A first output end of the second separator (7) is connected with the liquid carbon dioxide storage tank (8) and used for outputting the liquid carbon dioxide separated from the second fluid mixture. A second output end of the second separator (7) is connected with the input end of the first nitrogen gas conveying pipeline (16) and used for outputting the nitrogen gas separated from the second fluid mixture.

5. The solar energy power generation system of claim 4, wherein, The solar energy storage power generation system further comprises: A first circulating fan (3) is arranged on the first nitrogen gas conveying pipeline (16) and used for accelerating the flow of the nitrogen gas output from the second output end of the second separator (7) to the first input end of the calcium carbonate storage tank (1).

6. The solar energy power generation system of claim 1, wherein, The solar energy storage power generation system further comprises: A carbon dioxide booster pump (9) is arranged between the liquid carbon dioxide storage tank (8) and the calcium carbonate synthesis reactor (10) and used for pressurizing the liquid carbon dioxide before entering the calcium carbonate synthesis reactor (10).

7. The solar energy power generation system of claim 2, wherein, The solar energy storage power generation system further comprises: A calcium oxide storage tank (11) is connected with the second output end of the first separator (4) and used for storing the solid calcium oxide separated from the first separator (4).

8. The solar energy power generation system of claim 4, wherein, The solar energy storage power generation system further comprises: A third separator (12) is connected with the output end of the calcium carbonate synthesis reactor (10) and used for separating a third fluid mixture from the calcium carbonate synthesis reactor (10) into the calcium carbonate and the heated nitrogen gas. The third fluid mixture is formed by the calcium carbonate and the heated nitrogen gas.

9. The solar energy power generation system of claim 8, wherein, A second output end of the third separator (12) is connected with the second input end of the calcium carbonate storage tank (1) and used for conveying the calcium carbonate separated from the third fluid mixture to the calcium carbonate storage tank (1).

10. The solar energy power generation system of claim 7, wherein, The solar energy storage power generation system further comprises: A second nitrogen gas conveying pipeline (17) is connected with the output end of the expander (14) and used for conveying the nitrogen gas output from the expander (14) to the calcium oxide storage tank (11). A second circulating fan (13) is arranged on the second nitrogen gas conveying pipeline and used for accelerating the flow of the nitrogen gas output from the expander (14) to the second input end of the calcium oxide storage tank (11).

Images