Fluidized bed reactor and supercritical carbon dioxide combined solar power generation system

Abstract

The present application relates to the technical field of photo-thermal power generation, in particular to a fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system. The system comprises a calcination system, a heat exchange system, a power generation system and a fluidized bed reactor. The calcination system comprises a solar heating module, a calcination reactor, a calcium carbonate storage container, a carbon dioxide storage unit and a calcium oxide storage container connected with the calcination reactor respectively; the power generation system comprises a first power generation system and a second power generation system; the inlet of the first power generation system is connected with the carbon dioxide storage unit; a pipe-in-pipe is arranged in the fluidized bed reactor for circulating supercritical carbon dioxide; the pipe-in-pipe is connected with the second power generation system. The present application has higher thermal efficiency, more stable fluidization performance and higher energy utilization rate through the integration of the pipe-in-pipe fluidized bed reactor, supercritical CO2 Brayton cycle and two-stage expansion power generation, and solves the problems of low overall cycle power generation efficiency and low thermal efficiency in the prior art.

Description

Technical Field

[0001] This invention relates to the field of solar thermal power generation technology, specifically to a fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system. Background Technology

[0002] Solar thermal power generation has become a highly anticipated energy form due to its cleanliness, efficiency, and widespread availability. Solar thermal power generation converts solar radiation into heat energy, which can then be used to generate electricity. However, solar thermal power generation is dependent on sunshine conditions and suffers from intermittency, limiting its potential for application in the power grid. Furthermore, traditional solar thermal power generation systems typically employ separate energy storage and power generation systems, resulting in large-scale equipment, high costs, and significant system heat losses.

[0003] Thermochemical energy storage, due to its high energy density and long-term energy storage capabilities, has become a research hotspot in the field of solar thermal power generation. Currently, combining solar energy with thermochemical energy storage for power generation is the mainstream trend. For example, existing technologies disclose a zero-carbon emission combined cooling, heating, and power (CCHP) system based on a solar methanol decomposition and synthesis cycle. This system targets applications that combine solar methanol decomposition, syngas combustion, and methanol synthesis cycles to achieve CCHP. However, its power generation method utilizes a steam Rankine cycle. Under normal circumstances, the operating temperature of a steam Rankine cycle is typically no higher than 300℃, and the operating pressure is no higher than 10MPa. The overall cycle power generation efficiency is low, with a thermal efficiency of approximately 30%–40%, making it unsuitable for large-scale solar energy applications. Summary of the Invention

[0004] To address the problems of low operating temperature, low overall cycle power generation efficiency, and low thermal efficiency in existing solar and thermochemical energy storage combined power generation technologies, the present invention aims to provide a fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows.

[0006] This invention provides a fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system, including a calcination system, a heat exchange system, a power generation system, and a fluidized bed reactor.

[0007] The calcination system includes a solar heating module and a calcination reactor, as well as a calcium carbonate storage container, a carbon dioxide storage unit, and a calcium oxide storage container connected to the calcination reactor. The system is configured to use the solar heating module to focus and reflect solar energy onto the calcination reactor, so that calcium carbonate is thermally decomposed in the calcination reactor to form carbon dioxide and calcium oxide, which are then stored in the carbon dioxide storage unit and the calcium oxide storage container, respectively.

[0008] The heat exchange system includes a second heat exchanger; the low-temperature inlet of the second heat exchanger is connected to the outlet of the first power generation system; the low-temperature outlet of the second heat exchanger is connected to the gas phase inlet of the fluidized bed reactor; the high-temperature inlet of the second heat exchanger is connected to the solid phase outlet of the fluidized bed reactor; the high-temperature outlet of the second heat exchanger is connected to the calcium carbonate storage container; and the solid phase inlet of the fluidized bed reactor is connected to the outlet of the calcium oxide storage container.

[0009] The power generation system includes a first power generation system and a second power generation system; the inlet of the first power generation system is connected to the outlet of the carbon dioxide storage unit; a buried pipe is arranged inside the fluidized bed reactor for circulating supercritical carbon dioxide; the two ends of the buried pipe are respectively connected to the two ends of the second power generation system.

[0010] This invention employs a supercritical CO2 Brayton cycle, directly coupled with a fluidized bed reactor, to convert reaction heat into mechanical energy for power generation. This direct coupling reduces the complexity of traditional heat exchange and circulation equipment, significantly improving power generation efficiency. The supercritical CO2 Brayton cycle boasts high thermal efficiency and a small system footprint, making it suitable for high-temperature applications. Compared to traditional fluidized bed reactor-steam cycle coupling schemes, the supercritical CO2 Brayton cycle offers higher power generation efficiency and better environmental adaptability, addressing the issues of low operating temperatures, low overall cycle power generation efficiency, and low thermal efficiency inherent in existing solar and thermochemical energy storage combined power generation technologies.

[0011] The fluidized bed reactor of this invention achieves a highly efficient and compact reaction and power generation system structure through its embedded tube design, optimized gas-solid distribution structure, integration of supercritical CO2 Brayton cycle, and two-stage expansion power generation. Compared with existing technologies, the fluidized bed reactor with embedded tubes of this invention possesses higher thermal efficiency, more stable fluidization performance, and higher energy utilization rate. These characteristics provide an innovative solution for the efficient conversion and energy storage applications of solar thermochemical energy.

[0012] Preferably, a distribution plate is provided at the bottom of the fluidized bed reactor, and the distribution plate has ventilation openings for uniformly distributing carbon dioxide gas flow. Preferably, multiple baffles are provided in the fluidized bed reactor, and the multiple baffles are vertically arranged on the distribution plate; multiple buried pipes are arranged horizontally in the fluidized bed reactor, and the multiple buried pipes pass through the multiple baffles, and the multiple buried pipes are connected end to end in sequence.

[0013] In this invention, a distribution plate is installed at the bottom of the fluidized bed reactor to uniformly distribute the CO2 gas flow rate; simultaneously, baffles are vertically installed inside the fluidized bed reactor to control the flow patterns of gas and solid particles. The configuration of the distribution plate and baffles optimizes the flow and mixing of the gas and solid phases within the fluidized bed reactor, improves the uniform fluidization of solid particles, and thus enhances heat and mass transfer efficiency. This structure significantly enhances heat transfer efficiency, avoids localized overheating or uneven fluidization, and ensures the stability and overall thermal efficiency of the reactor.

[0014] Preferably, the heat exchange system includes a first heat exchanger, the high-temperature side inlet of the first heat exchanger being connected to the gas phase outlet of the calcination reactor, the high-temperature side outlet of the first heat exchanger being connected to the carbon dioxide storage unit; the low-temperature side inlet of the first heat exchanger being connected to the calcium carbonate storage container, and the low-temperature side outlet of the first heat exchanger being connected to the inlet of the calcination reactor.

[0015] This invention utilizes the heat energy reflected by focused sunlight, and simultaneously uses a first heat exchanger to exchange heat with the high-temperature carbon dioxide gas stream after calcination, thereby increasing the temperature of calcium carbonate entering the calcination reactor. Thus, by utilizing the heat energy reflected by focused sunlight and combining it with the recovered waste heat from the chemical reaction, the calcination temperature of calcium carbonate in the calcination reactor can be rapidly raised to 900°C.

[0016] Preferably, the carbon dioxide storage unit includes a first compressor and a carbon dioxide storage container; the high-temperature side outlet of the first heat exchanger is connected to the first compressor; the inlet of the carbon dioxide storage container is connected to the first compressor; and the outlet of the carbon dioxide storage container is connected to the first power generation system.

[0017] Preferably, the first power generation system includes a first expander and a first generator; the first expander is coupled to the first generator, the outlet of the carbon dioxide storage unit is connected to the inlet of the first expander, and the low-temperature side inlet of the second heat exchanger is connected to the outlet of the first expander.

[0018] Preferably, the gas phase outlet of the fluidized bed reactor is connected to the inlet of the second compressor; the low-temperature side inlet of the second heat exchanger is connected to the outlet of the first expander and the outlet of the second compressor, respectively.

[0019] Preferably, the second power generation system includes a second expander and a second generator; the second expander is coupled to the second generator, the inlet of the buried pipe is connected to the outlet of the second expander, and the outlet of the buried pipe is connected to the inlet of the second expander.

[0020] This invention utilizes a two-stage expansion power generation system based on the heat of reaction. A first expander and a second expander drive a first generator and a second generator, respectively, and the system generates electricity efficiently using supercritical CO2 circulating within a fluidized bed reactor. Through this two-stage expansion power generation design, the system can fully utilize the thermal energy of supercritical CO2, maximizing energy recovery and improving overall power generation efficiency. Compared to traditional single-stage expansion systems, this structure can recover energy stage by stage under different temperatures and pressures, enhancing the system's flexibility and economy.

[0021] Preferably, the solar heating module includes multiple heliostats, which are placed on the directional projection path of sunlight and configured to focus and reflect sunlight onto the calcining reactor.

[0022] The beneficial effects of this invention are:

[0023] 1. This invention employs a supercritical CO2 Brayton cycle, directly coupled with a fluidized bed reactor, to convert reaction heat into mechanical energy for power generation. This direct coupling reduces the complexity of traditional heat exchange and circulation equipment, significantly improving power generation efficiency. The supercritical CO2 Brayton cycle boasts high thermal efficiency and a small system footprint, making it suitable for high-temperature applications. Compared to traditional fluidized bed reactor-steam cycle coupling schemes, the supercritical CO2 Brayton cycle offers higher power generation efficiency and better environmental adaptability, addressing the issues of low operating temperatures, low overall cycle power generation efficiency, and low thermal efficiency inherent in existing solar and thermochemical energy storage combined power generation technologies.

[0024] 2. This invention primarily utilizes a two-stage expansion power generation system based on the heat of reaction. A first expander and a second expander drive a first generator and a second generator, respectively, utilizing supercritical CO2 circulation within a fluidized bed reactor for efficient power generation. Through this two-stage expansion power generation design, the system can fully utilize the thermal energy of supercritical CO2, maximizing energy recovery and improving overall power generation efficiency. Compared to traditional single-stage expansion systems, this structure allows for staged energy recovery under different temperatures and pressures, enhancing the system's flexibility and economy.

[0025] 3. The fluidized bed reactor of this invention is equipped with horizontally arranged buried pipes through which supercritical carbon dioxide circulates, directly absorbing the heat generated by the reaction and thus effectively increasing the temperature of the supercritical carbon dioxide. This design enables direct utilization of the heat of reaction, allowing supercritical CO2 to be heated to high temperatures inside the fluidized bed reactor without the need for an additional heat exchanger. Compared to the external heat exchange design of traditional fluidized bed reactors, the fluidized bed reactor with buried pipes in this invention can more efficiently increase the temperature of supercritical CO2, improve the thermal efficiency of the system, and reduce energy transfer losses.

[0026] 4. The fluidized bed reactor of this invention, through its embedded tube design, optimized gas-solid distribution structure, integration of supercritical CO2 Brayton cycle, and two-stage expansion power generation, achieves a highly efficient and compact reaction and power generation system structure. Compared with existing technologies, the fluidized bed reactor with embedded tubes of this invention possesses higher thermal efficiency, more stable fluidization performance, and higher energy utilization rate. These characteristics provide an innovative solution for the efficient conversion and energy storage applications of solar thermochemical energy. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system provided in one embodiment of the present invention.

[0028] Figure 2 This is a schematic diagram of the calcination reactor according to one embodiment of the present invention. (a) is a schematic diagram of the calcination reactor; (b) is an enlarged view of the embedded pipe outlined in (a).

[0029] Explanation of reference numerals in the attached figures:

[0030] 1. Heliostat; 2. Calcination reactor; 3. First heat exchanger; 4. First compressor; 5. Carbon dioxide storage container; 6. First expander; 7. First generator; 8. Second compressor; 9. Calcium carbonate storage container; 10. Second heat exchanger; 11. Fluidized bed reactor; 12. Second expander; 13. Second generator; 14. Calcium oxide storage container; 15. Embedded pipe; 16. Distribution plate; 17. Baffle. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0032] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that the terms "first," "second," etc., used in this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0034] Solar thermal power generation converts solar radiation into heat energy, which can then be used to generate electricity. However, solar thermal power generation is dependent on sunshine conditions and suffers from intermittent issues, limiting its potential for application in the power grid.

[0035] Currently, common solutions for solar thermal-driven power generation coupling systems include combining solar energy with methanol decomposition, syngas combustion, and methanol synthesis cycles to achieve combined cooling, heating, and power (CCHP). These systems primarily employ the steam Rankine cycle, also known as the ORC cycle, as the power generation method. However, the operating temperature of the steam Rankine cycle is typically limited to below 300°C and the operating pressure to no more than 10 MPa. The overall cycle power generation efficiency is relatively low, with thermal efficiency generally between 30% and 40%, making it difficult to meet the needs of large-scale solar energy applications.

[0036] This invention primarily utilizes a CaO / CaCO3 reaction system, suitable for medium- and high-temperature applications, and possesses excellent energy storage and release efficiencies. Furthermore, the supercritical carbon dioxide Brayton cycle exhibits higher thermal efficiency and greater economic and environmental friendliness in the medium- and high-temperature range. Fluidized bed reactors are widely used in chemical reactions, heat exchange, waste treatment, and other fields, demonstrating unique advantages, particularly their ability to achieve rapid and efficient heat transfer, and their contribution to reducing reactor volume and cost.

[0037] The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system of this invention mainly utilizes the reversible reaction coupling of the CaO / CaCO3 reaction system with a supercritical carbon dioxide cycle to achieve power generation, combining the advantages of high thermal efficiency and solar thermochemical conversion. Specifically, the thermal efficiency of the supercritical CO2 Brayton cycle of this invention can reach 40%–50%, and under optimal design conditions, it can even approach 50%–60%. This is primarily due to the high density characteristics of supercritical CO2 and its extremely low compression work requirement. Supercritical CO2 refers to supercritical carbon dioxide. The operating temperature of the supercritical carbon dioxide power generation system of this invention is 500℃–800℃, and the operating pressure is 20MPa–30MPa, which can even exceed 35MPa under specific conditions.

[0038] Furthermore, traditional solar thermal power generation systems typically employ separate energy storage and power generation systems, resulting in large-scale equipment, high costs, and significant system heat losses. To overcome these problems, this invention proposes a design that tightly integrates a fluidized bed exothermic reactor with embedded pipes with a supercritical carbon dioxide solar power generation system. This highly compact and efficient integrated system not only significantly reduces the equipment footprint but also improves energy conversion efficiency and overall system performance. Moreover, this compact integrated system is better suited to the intermittent nature of solar thermal power generation, providing a practical solution for large-scale solar energy applications.

[0039] The technical solution of the present invention will be further described below through specific embodiments. Unless otherwise specified, the methods described in the following embodiments are conventional methods; the reagents and materials described are commercially available unless otherwise specified.

[0040] like Figure 1 A fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system, comprising a calcination system, a heat exchange system, a power generation system and a fluidized bed reactor.

[0041] The calcination system includes a solar heating module and a calcination reactor 2, as well as a calcium carbonate storage container 9, a carbon dioxide storage unit, and a calcium oxide storage container 14, which are respectively connected to the calcination reactor 2. The system is configured to use the solar heating module to focus and reflect solar energy onto the calcination reactor 2, so that the calcium carbonate from the calcium carbonate storage container 9 is thermally decomposed in the calcination reactor 2 to form carbon dioxide and calcium oxide, which are then stored in the carbon dioxide storage unit and the calcium oxide storage container 14, respectively.

[0042] Specifically, the solar heating module includes multiple heliostats 1, which are placed in the directional projection path of sunlight and configured to focus and reflect sunlight onto the calcining reactor 2. The calcining reactor 2 is equipped with lenses or skylights, allowing the heat energy reflected from the focused sunlight to enter the calcining reactor 2 through the lenses or skylights, providing heat energy for the calcination reaction inside the calcining reactor 2.

[0043] Based on the above embodiments, as a preferred embodiment, the heat exchange system includes a first heat exchanger 3. The high-temperature inlet of the first heat exchanger 3 is connected to the gas phase outlet of the calcination reactor 2, and the high-temperature outlet of the first heat exchanger 3 is connected to the carbon dioxide storage unit. The low-temperature inlet of the first heat exchanger 3 is connected to the calcium carbonate storage container 9, and the low-temperature outlet of the first heat exchanger 3 is connected to the inlet of the calcination reactor 2. The inlet of the calcium oxide storage container 14 is connected to the solid phase outlet of the calcination reactor 2, and the outlet of the calcium oxide storage container 14 is connected to the solid phase inlet of the fluidized bed reactor 11.

[0044] Specifically, calcium carbonate storage container 9 stores calcium carbonate solid powder; carbon dioxide storage unit stores carbon dioxide gas; and calcium oxide storage container 14 stores calcium oxide solid powder.

[0045] One embodiment of the present invention utilizes the heat energy reflected by focused sunlight, and simultaneously uses the first heat exchanger 3 to exchange heat with the temperature of the high-temperature carbon dioxide gas flow after calcination, thereby increasing the temperature of calcium carbonate entering the calcination reactor 2. Thus, by utilizing the heat energy reflected by focused sunlight and combining it with the recovered waste heat from the chemical reaction, the calcination temperature of calcium carbonate in the calcination reactor 2 can be rapidly raised to 900°C.

[0046] Based on the above embodiments, as a preferred embodiment, the carbon dioxide storage unit includes a first compressor 4 and a carbon dioxide storage container 5; the high-temperature side outlet of the first heat exchanger 3 is connected to the first compressor 4; the inlet of the carbon dioxide storage container 5 is connected to the first compressor 4; and the outlet of the carbon dioxide storage container 5 is connected to the first power generation system.

[0047] The heat exchange system includes a second heat exchanger 10; the low-temperature inlet of the second heat exchanger 10 is connected to the outlet of the first power generation system; the low-temperature outlet of the second heat exchanger 10 is connected to the gas phase inlet of the fluidized bed reactor 11; the high-temperature inlet of the second heat exchanger 10 is connected to the solid phase outlet of the fluidized bed reactor 11; the high-temperature outlet of the second heat exchanger 10 is connected to the calcium carbonate storage container 9; and the solid phase inlet of the fluidized bed reactor 11 is connected to the outlet of the calcium oxide storage container 14.

[0048] The power generation system includes a first power generation system and a second power generation system; the inlet of the first power generation system is connected to the outlet of the carbon dioxide storage unit; a buried pipe 15 is arranged inside the fluidized bed reactor 11 for circulating supercritical carbon dioxide; the two ends of the buried pipe 15 are respectively connected to the two ends of the second power generation system.

[0049] Specifically, this invention employs a supercritical CO2 Brayton cycle, directly coupled with a fluidized bed reactor 11, to convert reaction heat into mechanical energy, which is then used for power generation. This direct coupling reduces the complexity of traditional heat exchange and circulation equipment, significantly improving power generation efficiency. The supercritical CO2 Brayton cycle has high thermal efficiency and a small system footprint, making it suitable for high-temperature applications. Compared to traditional fluidized bed reactor-steam cycle coupling schemes, the supercritical CO2 Brayton cycle offers higher power generation efficiency and better environmental adaptability.

[0050] Furthermore, the embodiment of this invention primarily utilizes a two-stage expansion power generation system based on the heat of reaction. A first expander and a second expander drive a first generator and a second generator, respectively, utilizing the supercritical CO2 circulation within the fluidized bed reactor 11 for efficient power generation. Through this two-stage expansion power generation design, the system can fully utilize the thermal energy of supercritical CO2, maximizing energy recovery and improving overall power generation efficiency. Compared to traditional single-stage expansion systems, this structure can recover energy stage by stage under different temperatures and pressures, enhancing the system's flexibility and economy.

[0051] Specifically, the fluidized bed reactor 11 is equipped with horizontally arranged buried pipes 15. The circulating supercritical CO2 within these pipes absorbs the heat of reaction within the fluidized bed reactor and then flows to the second expander 12 for expansion and power generation. In this embodiment of the invention, the fluidized bed reactor features horizontally arranged buried pipes containing circulating supercritical carbon dioxide, which directly absorbs the heat generated by the reaction, thereby effectively increasing the temperature of the supercritical carbon dioxide. This design enables direct utilization of the heat of reaction, allowing supercritical CO2 to be heated to a high temperature within the fluidized bed reactor without the need for an additional heat exchanger. Compared to the external heat exchange design of traditional fluidized bed reactors, the fluidized bed reactor with buried pipes in this embodiment of the invention can more efficiently increase the temperature of supercritical CO2, improve the system's thermal efficiency, and reduce energy transfer losses.

[0052] Based on the above embodiments, as a preferred embodiment, a distribution plate 16 is provided at the bottom of the fluidized bed reactor 11. The distribution plate 16 has ventilation openings for uniformly distributing carbon dioxide gas flow and improving the fluidization effect. Multiple baffles 17 are provided inside the fluidized bed reactor 11, all vertically arranged on the distribution plate 16. Multiple buried pipes 15 are arranged horizontally inside the fluidized bed reactor 11, passing through the multiple baffles 17, and are connected end-to-end in sequence.

[0053] Specifically, in this embodiment of the invention, a distribution plate 16 is installed at the bottom of the fluidized bed reactor 11 to uniformly distribute the CO2 gas flow rate; simultaneously, a baffle 17 is vertically arranged inside the fluidized bed reactor 11 to control the flow pattern of gas and solid particles. The configuration of the distribution plate 16 and the baffle 17 optimizes the flow and mixing effect of the gas and solid phases inside the fluidized bed reactor 11, improves the uniform fluidization of solid particles, and thus improves heat and mass transfer efficiency. This structure can significantly improve heat transfer efficiency, avoid the problems of local overheating or uneven fluidization, and ensure the stability and overall thermal efficiency of the reactor.

[0054] Specifically, the fluidized bed reactor 11 of this invention, through its embedded pipe 15 design, optimized gas-solid distribution structure, integration of supercritical CO2 Brayton cycle, and two-stage expansion power generation characteristics, achieves a highly efficient and compact reaction and power generation system structure. Compared with existing technologies, the fluidized bed reactor with embedded pipe of this invention possesses higher thermal efficiency, more stable fluidization performance, and higher energy utilization rate. These characteristics provide an innovative solution for the efficient conversion and energy storage applications of solar thermochemical energy.

[0055] Based on the above embodiments, as a preferred embodiment, the gas phase outlet of the fluidized bed reactor 11 is connected to the inlet of the second compressor 8; the low-temperature side inlet of the second heat exchanger 10 is connected to the outlet of the first expander 6 and the outlet of the second compressor 8, respectively.

[0056] Based on the above embodiments, as a preferred embodiment, the first power generation system includes a first expander 6 and a first generator 7; the first expander 6 is coupled to the first generator 7, the outlet of the carbon dioxide storage unit is connected to the inlet of the first expander 6, and the low-temperature side inlet of the second heat exchanger 10 is connected to the outlet of the first expander 6.

[0057] Based on the above embodiments, as a preferred embodiment, the second power generation system includes a second expander 12 and a second generator 13; the second expander 12 is coupled to the second generator 13, the inlet of the buried pipe 15 is connected to the outlet of the second expander 12, and the outlet of the buried pipe 15 is connected to the inlet of the second expander 12.

[0058] Specifically, when there is solar radiation, sunlight is focused and reflected by heliostat 1 onto calcination reactor 2. Calcium carbonate particles decompose endothermally in calcination reactor 2, generating calcium oxide and carbon dioxide, thus achieving the absorption and conversion of thermal energy. The gas phase outlet of calcination reactor 2 is connected to the high-temperature inlet of the first heat exchanger 3 via a pipe. The high-temperature outlet of the first heat exchanger 3 is connected to the first compressor 4, while the low-temperature side of the first heat exchanger 3 is connected between the calcium carbonate storage container 9 and the inlet of calcination reactor 2, realizing the transfer and recovery of calcination reaction heat energy. Carbon dioxide storage container 5 is connected to the outlet of the first compressor 4 via a pipe. After compression, carbon dioxide is stored in carbon dioxide storage container 5. Simultaneously, the outlet of carbon dioxide storage container 5 is connected to the inlet of the first expander 6 to achieve gas circulation and storage in the system.

[0059] The first expander 6 and the second expander 12 are coupled to the first generator 7 and the second generator 12 respectively, so as to realize the effective conversion of mechanical energy during the expansion process and improve the power generation efficiency of the system.

[0060] The high-temperature side inlet of the second heat exchanger 10 is connected to the solid phase outlet of the fluidized bed reactor 11, the high-temperature side outlet of the second heat exchanger 10 is connected to the calcium carbonate storage container 9, the low-temperature side inlet of the second heat exchanger 10 is connected to the outlet of the first expander 6 and the second compressor 8, and the low-temperature side outlet of the second heat exchanger 10 is connected to the gas phase inlet of the fluidized bed reactor 11.

[0061] like Figure 2 The fluidized bed reactor 11 has a gas phase outlet at the top, which is connected to the inlet of the second compressor 8. The fluidized bed reactor 11 has a buried pipe 15 arranged horizontally. The power circulation is achieved by circulating supercritical CO2. After absorbing the reaction heat in the fluidized bed reactor 11, the supercritical CO2 in the buried pipe 15 flows to the second expander 12 to expand and do work, and drives the second generator 12 to generate electricity.

[0062] A distribution plate 16 is installed at the bottom of the fluidized bed reactor 11. The vents on the distribution plate 16 are used to uniformly distribute the carbon dioxide gas flow and improve the fluidization effect. In addition, vertical baffles 17 are provided inside the fluidized bed reactor 11 to optimize the flow and residence time of the reaction gas and solid particles and enhance the heat exchange efficiency.

[0063] Specifically, when there is no solar radiation or the solar radiation is poor, the carbon dioxide stored in the carbon dioxide storage container 5 drives the first generator 7 to generate electricity normally via the first expander 6. The expanded carbon dioxide then enters the fluidized bed reactor 11. In the fluidized bed reactor 11, it undergoes a carbonation reaction with the calcium oxide from the calcium oxide storage container 14 to generate calcium carbonate and release a large amount of heat energy to heat the supercritical CO2. This heats the second expander 12 to expand and generate electricity, which in turn drives the second generator 12 to achieve a supercritical CO2 Brayton cycle, thus completing the power generation.

[0064] In one embodiment of the present invention, a fluidized bed reactor 11 with embedded pipe 15 is combined with a supercritical carbon dioxide solar power generation system. The supercritical CO2 absorbs the heat of reaction by circulating through the embedded pipe 15 in the fluidized bed reactor 11, which significantly improves the power generation efficiency, optimizes the compactness and economy of the system, and has broad application prospects.

[0065] The fluidized bed reactor 11 is equipped with a distribution plate 16 and a baffle 17, which optimizes the flow and residence time of gas and solid particles, effectively improves heat exchange efficiency, accelerates the reaction rate and improves the utilization rate of reactants, making the reaction process of the system more efficient and complete, and further enhancing the thermal energy utilization rate.

[0066] This design, based on a fluidized bed exothermic reactor with buried pipes and a supercritical carbon dioxide solar power generation system, not only possesses high power generation capacity and a compact structure, but also has a scientifically effective operation mode, which is of great benefit to improving the stability, reliability and economy of solar thermal power generation systems.

[0067] The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system provided by the embodiments of the present invention not only reduce the equipment footprint but also significantly improve energy conversion efficiency and enhance the overall system performance. Furthermore, the compact integrated system can better match the intermittent nature of solar thermal power generation, providing a practical solution for large-scale solar energy applications.

[0068] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fluidized bed reactor and a supercritical carbon dioxide combined solar power generation system, characterized in that, This includes a calcination system, a heat exchange system, a power generation system, and a fluidized bed reactor; The calcination system includes a solar heating module and a calcination reactor (2), as well as a calcium carbonate storage container (9), a carbon dioxide storage unit and a calcium oxide storage container (14) connected to the calcination reactor (2) respectively. It is configured to use the solar heating module to focus and reflect solar energy to the calcination reactor (2) so that calcium carbonate is thermally decomposed in the calcination reactor (2) to form carbon dioxide and calcium oxide, which are stored in the carbon dioxide storage unit and the calcium oxide storage container (14) respectively. The heat exchange system includes a second heat exchanger (10); the power generation system includes a first power generation system and a second power generation system; the low-temperature inlet of the second heat exchanger (10) is connected to the outlet of the first power generation system; the low-temperature outlet of the second heat exchanger (10) is connected to the gas phase inlet of the fluidized bed reactor (11); the high-temperature inlet of the second heat exchanger (10) is connected to the solid phase outlet of the fluidized bed reactor (11); the high-temperature outlet of the second heat exchanger (10) is connected to the calcium carbonate storage container (9); the solid phase inlet of the fluidized bed reactor (11) is connected to the outlet of the calcium oxide storage container (14). The inlet of the first power generation system is connected to the outlet of the carbon dioxide storage unit; a buried pipe (15) is arranged inside the fluidized bed reactor (11) for circulating supercritical carbon dioxide; the two ends of the buried pipe (15) are respectively connected to the two ends of the second power generation system. A distribution plate (16) is provided at the bottom of the fluidized bed reactor (11), and the distribution plate (16) has vents for uniformly distributing carbon dioxide gas flow. The fluidized bed reactor (11) is provided with multiple baffles (17), all of which are vertically arranged on the distribution plate (16); multiple buried pipes (15) are arranged horizontally in the fluidized bed reactor (11), and the multiple buried pipes (15) pass through the multiple baffles (17), and the multiple buried pipes (15) are connected end to end in sequence.

2. The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system according to claim 1, characterized in that, The heat exchange system includes a first heat exchanger (3), the high-temperature side inlet of the first heat exchanger (3) is connected to the gas phase outlet of the calcination reactor (2), the high-temperature side outlet of the first heat exchanger (3) is connected to the carbon dioxide storage unit; the low-temperature side inlet of the first heat exchanger (3) is connected to the calcium carbonate storage container (9), and the low-temperature side outlet of the first heat exchanger (3) is connected to the inlet of the calcination reactor (2).

3. The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system according to claim 2, characterized in that, The carbon dioxide storage unit includes a first compressor (4) and a carbon dioxide storage container (5); the high-temperature side outlet of the first heat exchanger (3) is connected to the first compressor (4); The inlet of the carbon dioxide storage container (5) is connected to the first compressor (4); the outlet of the carbon dioxide storage container (5) is connected to the first power generation system.

4. The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system according to claim 1, characterized in that, The first power generation system includes a first expander (6) and a first generator (7); the first expander (6) is coupled to the first generator (7), the outlet of the carbon dioxide storage unit is connected to the inlet of the first expander (6), and the low-temperature side inlet of the second heat exchanger (10) is connected to the outlet of the first expander (6).

5. The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system according to claim 4, characterized in that, The gas phase outlet of the fluidized bed reactor (11) is connected to the inlet of the second compressor (8); the low-temperature side inlet of the second heat exchanger (10) is connected to the outlet of the first expander (6) and the outlet of the second compressor (8), respectively.

6. The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system according to claim 1, characterized in that, The second power generation system includes a second expander (12) and a second generator (13); the second expander (12) is coupled to the second generator (13), the inlet of the buried pipe (15) is connected to the outlet of the second expander (12), and the outlet of the buried pipe (15) is connected to the inlet of the second expander (12).

7. The fluidized bed reactor and supercritical carbon dioxide combined solar power generation system according to claim 1, characterized in that, The solar heating module includes multiple heliostats (1), which are placed on the directional projection path of sunlight and configured to focus and reflect sunlight onto the calcining reactor (2).

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