High-throughput solar thermochemical energy storage system and method based on reversible chemical reaction

Abstract

The present invention discloses a high-throughput solar thermochemical energy storage system and method based on a reversible chemical reaction. The system of the present invention is based on a reversible chemical reaction driven by solar heat collection, and includes a solar concentrating device, an endothermic reaction unit, an exothermic reaction unit, and a reactant storage device. When the sunlight conditions are sufficient, the heat of the reaction products is recovered to the maximum extent through multiple heat exchanges in the closed endothermic reaction unit. At the same time, the vacuum pump continuously extracts the CO2 generated in the reactor to maintain it at a low partial pressure state, ensuring that the reaction continues to proceed in the forward direction. At night or when there is insufficient sunlight, the CaO particles generated by the endothermic reaction are transported to the CaO silo of the exothermic reaction unit as a reactant, and the heat generated by the reaction is recovered through the heat exchanger and the heat exchange tubes inside the multi-stage fluidized bed. The present invention can store energy when there is sufficient sunlight and release energy at night or when there is insufficient sunlight, ensuring an uninterrupted supply of heat energy around the clock. It can also increase the reaction temperature and energy utilization rate.

Description

Technical Field

[0001] The present invention relates to the field of solar thermochemical energy storage, and in particular to a high-throughput solar thermochemical energy storage system and method based on reversible chemical reactions. Background Art

[0002] Solar energy has always been known for its sustainability, cleanliness, and abundant reserves. However, conventional solar energy storage technologies suffer from low exothermic temperatures and low energy storage density, which undoubtedly significantly restrict the large-scale application of solar thermal power generation technology. Therefore, there is an urgent need to develop large-scale, efficient solar thermochemical energy storage systems with high energy storage density and high exothermic temperatures. The integration of high-throughput solar concentrating systems and thermochemical energy storage systems can achieve efficient conversion and utilization of light energy, heat energy, and chemical energy. Therefore, high-throughput concentrating solar thermochemical conversion energy storage systems have the advantages of high energy storage density, high efficiency, and high reaction temperature, making them one of the most promising large-scale solar energy storage technologies.

[0003] Thermochemical energy storage systems are developing towards high parameterization, which requires the collection temperature to be increased. The performance of energy storage materials and reactors is the main factor affecting the collection temperature. The main thermochemical energy storage materials currently being studied include metal oxides, sulfates, carbonates and hydroxides. Among them, CaCO3 / CaO has a great comprehensive advantage in energy storage density, heat release temperature and cost, and has good development potential. Therefore, it is driven by solar thermal energy collection. The reversible chemical reaction is applied in thermochemical energy storage systems to achieve efficient power generation and heat supply.

[0004] Solar thermochemical reactors are categorized as direct-irradiation and indirect-irradiation types. The direct-irradiation reactor integrates the heat collection chamber and reaction chamber, giving it the advantages of a simple structure and high thermal efficiency, and promising prospects for industrial application. However, when illumination is uneven, direct-irradiation reactors are prone to problems such as uneven flow and localized overheating. This is especially true when micron-sized fine particles are used as energy storage materials, which are more prone to agglomeration. This reduces the effective reaction surface area and makes fluidization difficult, leading to a significant decrease in reaction performance. Furthermore, fine particles tend to adhere to the surface of the reactor's quartz window, causing a serious "screen explosion" problem under high-throughput concentrated solar illumination conditions. Indirect-irradiation reactors, on the other hand, have separate heat collection chambers and reaction chambers, thus buffering uneven heat flow and preventing particle agglomeration and sintering. However, this structure also easily leads to large temperature gradients within the reaction chamber, reducing reaction efficiency. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-throughput solar thermochemical energy storage system and method based on reversible chemical reactions, so as to effectively solve the problems of low energy storage density and low heat release temperature of conventional solar energy storage technology. The high-throughput concentrated solar thermochemical conversion energy storage system adopted in the present invention has the advantages of high energy storage density and efficiency and high reaction temperature.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A high-throughput solar thermochemical energy storage system based on reversible chemical reactions, comprising a solar concentrator, a high-throughput concentrating solar endothermic reaction unit, an exothermic reaction unit, and a reactant storage device;

[0008] The solar concentrating device includes a concentrator;

[0009] The high-throughput concentrated solar endothermic reaction unit includes an inclined plate moving bed, a fan a, a heat exchanger a, a cooler, a compressor and a CO2 gas cylinder a;

[0010] The exothermic reaction unit includes a multi-stage fluidized bed, a heat exchanger b, a heat exchanger c, a blower b and a CO2 gas cylinder b;

[0011] The reactant storage device includes a CaCO3 silo a, a CaCO3 silo b, a CaO silo a and a CaO silo b;

[0012] The solid outlet of the CaCO3 silo a is connected to the feed port of the inclined plate moving bed, the discharge port of the inclined plate moving bed is connected to the solid inlet of the CaO silo a, and the CO2 gas outlet of the inclined plate moving bed is connected to the CO2 gas cylinder a through the heat exchanger a, the cooler, and the compressor in sequence;

[0013] The concentrator is used to concentrate sunlight onto the inclined plate moving bed, and the CaCO3 solid particles inside the inclined plate moving bed complete the chemical reaction by absorbing heat;

[0014] An air circulation is formed between the air outlet of the blower a, the air inlet and air outlet of the CaO silo a, the air inlet and air outlet of the heat exchanger a, the air inlet and air outlet of the CaCO3 silo a, and the air inlet of the blower a through a pipeline;

[0015] The solid outlet of the CaO silo a is connected to the solid inlet of the CaO silo b, the solid outlet of the CaO silo b is connected to the feed inlet of the multi-stage fluidized bed, the discharge port of the multi-stage fluidized bed is connected to the solid inlet of the CaCO3 silo b, and the solid outlet of the CaCO3 silo b is connected to the solid inlet of the CaCO3 silo a;

[0016] The gas inlet of the CaCO3 silo b is connected to the low-temperature heating medium, and the gas outlet of the CaCO3 silo b is connected to the heating medium inlet of the multi-stage fluidized bed through the heat exchanger b, and the heating medium outlet of the multi-stage fluidized bed outputs the high-temperature working medium;

[0017] The gas outlet of the multi-stage fluidized bed, the heat exchanger b, the gas inlet and gas outlet of the CaO silo, the high-temperature side inlet of the heat exchanger c, the fan b, the CO2 gas cylinder b, the low-temperature side inlet of the heat exchanger c and the gas inlet of the multi-stage fluidized bed are connected in sequence by pipelines to form a CO2 cycle.

[0018] Furthermore, a quartz window for transmitting sunlight is provided on the top of the inclined plate moving bed.

[0019] Furthermore, three chambers are provided inside the multi-stage fluidized bed. After the CaO solid particles in the CaO silo b enter the first chamber, they flow into the second chamber and the third chamber in sequence by overflow.

[0020] Furthermore, the multi-stage fluidized bed is provided with heat exchange tubes b that are evenly staggered.

[0021] Furthermore, the CaCO3 silo a, CaCO3 silo b, CaO silo a and CaO silo b are all provided with heat exchange tubes a, and the ports of the heat exchange tubes a are the gas inlets and outlets of each silo.

[0022] Furthermore, the gas inlet of the multi-stage fluidized bed is provided with a hood.

[0023] Furthermore, the high-throughput concentrated solar endothermic reaction unit also includes a vacuum pump, which is arranged between the cooler and the compressor.

[0024] Furthermore, the energy storage materials CaCO3 particles and CaO particles in the reactant storage device are both modified calcium-based materials CaMM, the CaCO3 particles are composed of CaCO3, MgO and Ca2MnO4, and the CaO particles are composed of CaO, MgO and Ca2MnO4, and the atomic molar ratio of Ca, Mn and Mg in the CaCO3 particles and CaO particles is 9:1:1.

[0025] A high-throughput solar thermochemical energy storage method based on reversible chemical reactions: When the sunshine conditions are sufficient, in the endothermic reaction unit, the CaCO3 particles in the CaCO3 silo a enter the inclined plate moving bed and are directly irradiated by the sunlight reflected by the concentrator, endothermally decomposed into high-temperature CaO particles and high-temperature CO2. The cold air sent from the fan a exchanges heat with the high-temperature CaO particles produced by the reaction in the CaO silo b. The heated air is further transported to the heat exchanger a to exchange heat with the high-temperature CO2 produced by the reaction. The fully heated air is sent to the CaCO3 silo to preheat the CaCO3 particles at the feed port of the inclined plate moving bed. The CO2 preliminarily cooled by the heat exchanger a is transported to the cooler for further cooling, compressed by the compressor, and stored in the CO2 cylinder a.

[0026] At night or when there is insufficient sunlight, in the exothermic reaction unit, CaO particles and CO2 enter the multi-stage fluidized bed from the feed port and gas inlet respectively to react, generating high-temperature CaCO3 particles and generating a large amount of heat. The low-temperature heating working fluid enters the CaCO3 silo b to exchange heat with the high-temperature CaCO3 particles generated by the reaction. The heated working fluid is transported to the heat exchanger b to exchange heat with the high-temperature CO2 at the gas outlet of the reactor. The further heated working fluid is sent to the multi-stage fluidized bed to recover the heat generated by the reaction. After being fully heated to 850°C, it flows out and can be used for power generation and heat supply later. Secondly, the high-temperature CO2 preliminarily cooled by the heat exchanger b is transported to the CaO silo b to preheat the CaO particles at the feed port of the multi-stage fluidized bed. Finally, the further cooled CO2 is transported to the heat exchanger c to exchange heat with the low-temperature CO2 sent from the CO2 cylinder b. After being fully cooled, it is sent to the gas inlet of the multi-stage fluidized bed and sent into the multi-stage fluidized bed reaction chamber for reaction.

[0027] Furthermore, when the sunlight conditions are sufficient, the CaO particles produced by the endothermic reaction are stored in the CaO silo a and subjected to heat exchange cooling there. At night or when the light conditions are insufficient, the CaO particles in the CaO silo a are transported to the CaO silo b as reactants for the exothermic reaction. Similarly, at night or when the light conditions are insufficient, the CaCO3 particles of the exothermic reaction are stored in the CaCO3 silo b and subjected to heat exchange cooling there. When the sunlight conditions are sufficient, the CaCO3 particles in the CaCO3 silo b are transported to the CaCO3 silo a as reactants for the endothermic reaction.

[0028] Compared with the prior art, the present invention has the following beneficial technical effects:

[0029] (1) The high-throughput solar thermochemical energy storage system based on reversible chemical reaction provided by the present invention involves a solar thermal energy storage system driven by The reversible chemical reaction is completed in the inclined plate moving bed of the high-throughput concentrated solar energy endothermic reaction unit, and the reverse reaction is completed in the multi-stage fluidized bed of the exothermic reaction unit. The entire thermochemical energy storage system realizes the self-production and self-use of reactants and products, efficiently utilizes the heat of the reaction products, and realizes the resource utilization of CO2.

[0030] (2) The present invention adopts the CaCO3 / CaO system, which has the advantages of high energy storage density and high exothermic temperature. The energy storage density can reach 3.2GJ / m 3 , the exothermic temperature can reach 850℃; in addition, CaO material is not only widely distributed and easy to obtain, but also inexpensive, which effectively reduces the construction cost of the energy storage system.

[0031] (3) The high-throughput solar thermochemical energy storage system based on reversible chemical reactions provided by the present invention uses a moving bed reactor for the endothermic reaction unit to carry out the direct solar heat absorption energy storage chemical reaction, which can effectively avoid the serious problem of particles adhering to the surface of the reactor quartz window and causing "screen explosion". In addition, a vacuum pump is used to continuously extract the CO2 generated in the reactor, so that the CO2 in the reactor is always at a low partial pressure state, ensuring that the reaction continues in the forward direction.

[0032] (4) The high-throughput solar thermochemical energy storage system and method based on reversible chemical reactions provided by the present invention successively adopts multiple heat exchange devices to heat the working fluid for the exothermic reaction unit, and efficiently recovers the heat released during the reaction process. Before the reactants flow into the reactor, they are preheated in the heat exchange equipment using the sensible heat of the products flowing out of the reactor, thereby improving the energy utilization rate of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0034] Figure 1 The figure is a schematic diagram of the working process of the system of the present invention.

[0035] Figure 2 This is a general schematic diagram of the system workflow of the present invention.

[0036] Among them, 1-concentrator; 2-inclined plate moving bed; 3-fan a; 4-heat exchanger a; 5-cooler; 6-vacuum pump; 7-compressor; 8-CO2 gas cylinder a; 9-multi-stage fluidized bed; 10-heat exchanger b; 11-heat exchanger c; 12-fan b; 13-CO2 gas cylinder b; 14-CaCO3 silo a; 15-CaO silo a; 16-CaO silo b; 17-CaCO3 silo b; 18-quartz window; 19-heat exchange tube a; 20-heat exchange tube b; 21-wind hood. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0038] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0039] like Figure 1 As shown, a high-throughput solar thermochemical energy storage system based on reversible chemical reactions includes a solar concentrator, a high-throughput concentrating solar endothermic reaction unit, an exothermic reaction unit, and a reactant storage device;

[0040] The solar concentrating device comprises a concentrator 1;

[0041] The high-throughput concentrated solar endothermic reaction unit is carried out under sufficient sunlight conditions and includes an inclined plate moving bed 2, a fan a3, a heat exchanger a4, a cooler 5, a vacuum pump 6, a compressor 7, and a CO2 cylinder a8. The inclined plate moving bed 2 has dimensions of 700×200×650 mm, an inclined surface length of 808 mm, an inclination angle of 30°, and is provided with a solid particle feed port, a solid particle discharge port, and a gas outlet. The vacuum degree of the vacuum pump 6 is 0.08 MPa.

[0042] The exothermic reaction unit mainly works at night or when there is no sunlight input, and includes a multi-stage fluidized bed 9, a heat exchanger b10, a heat exchanger c11, a blower b12, and a CO2 cylinder b13. The dimensions of the multi-stage fluidized bed 9 are 510×100×600mm, of which the reaction bed part is 350mm high and the wind box is 240mm high. The total volume of the fluidized bed is 0.01m 3 , where chamber 1 ( Figure 2The multi-stage fluidized bed 9 (from left to right, chambers 1, 2, and 3) has a volume of 0.002 m 3 , chambers 2 and 3 are both 0.004m 3 ; and is provided with a solid particle feed port, a solid particle discharge port, a gas inlet and a gas outlet;

[0043] The endothermic reaction unit and the exothermic reaction unit correspond to the energy storage unit and the energy release unit of the high-throughput solar thermochemical energy storage system, respectively. The solid particle circulation rate is 40 kg / h and the reaction temperature is 750°C, that is, the exothermic temperature of the energy release unit is 750°C.

[0044] The reactant storage device includes a CaCO3 silo a14, a CaCO3 silo b17, a CaO silo a15 and a CaO silo b16; the CaCO3 silo a14, the CaCO3 silo b17, the CaO silo a15 and the CaO silo b16 are respectively provided with a solid particle feed port, a solid particle discharge port, a gas inlet and a gas outlet; when the sunlight conditions are sufficient, the CaCO3 particles are transported from the CaCO3 silo b17 to the CaCO3 silo a14 for an endothermic reaction; when the sunlight conditions are insufficient, the CaO particles are transported from the CaO silo a15 to the CaO silo b16 for an exothermic reaction; in order to improve the stability of the energy storage cycle process, the energy storage material CaCO3 / CaO particles are all modified calcium-based materials CaMM (CaCO3 / CaO+MgO+Ca2MnO4), in which the atomic molar ratio of Ca, Mn and Mg is 9:1:1.

[0045] The sunlight is concentrated onto the inclined plate moving bed 2 through the concentrator 1, and the solid particles directly absorb heat to complete the chemical reaction. For the energy storage chemical reaction of direct solar heat absorption, the use of a moving bed reactor can effectively avoid the serious problem of "screen explosion" caused by particles adhering to the surface of the quartz window 18 of the reactor.

[0046] In order to ensure the continuous progress of the reaction, each link of the system of the present invention is closed.

[0047] In order to improve the reaction conversion rate, the gas outlet of the inclined plate moving bed 2, the heat exchanger a4, the cooler 5, the vacuum pump 6, the compressor 7 and the CO2 cylinder a8 are connected in sequence by pipelines. The vacuum pump 6 continuously extracts the CO2 generated in the reactor, so that the reactor has a certain vacuum degree. The CO2 is always in a low partial pressure state in the reactor, thereby ensuring that the reaction continues to proceed in the forward direction; the function of the heat exchanger a4 and the cooler 5 is to reduce the temperature of the CO2 at the gas outlet of the reactor to ensure the normal operation of the vacuum pump 6.

[0048] In the exothermic reaction unit, in order to better control the fluidization time, a multi-stage fluidized bed 9 is used as a reactor, which has three chambers inside. The solid particles enter the next chamber by overflow to ensure that the CaO particles and CO2 fully react and improve the conversion rate. The fluidization speed is controlled by adjusting the wind speed, thereby achieving controllable fluidization speed.

[0049] In order to fully and efficiently recover the heat generated by the reaction, the three chambers of the multi-stage fluidized bed 9 are provided with uniformly staggered heat exchange tubes b20; in order to evenly distribute the air, a wind hood 21 is provided at the gas inlet of the fluidized bed.

[0050] In order to recover the heat of the reaction product solid particles, the reactant storage device, including the CaCO3 silo a14, the CaCO3 silo b17, the CaO silo a15 and the CaO silo b16, are all equipped with a heat exchange tube a19. The port of the heat exchange tube a19 is the gas inlet and outlet of the silo. The gas enters the heat exchange tube a19 and exchanges heat with the high-temperature solid particles outside the tube. The gas outlet of the multi-stage fluidized bed 9, the heat exchanger b10, the heat exchange tube a of the CaO silo b16, the high-temperature side inlet of the heat exchanger c11, the fan b12, the CO2 gas cylinder b13, the low-temperature side inlet of the heat exchanger c11 and the gas inlet of the multi-stage fluidized bed 9 are connected in sequence by pipelines to form a CO2 cycle; the heat exchange tube a of the CaCO3 silo b17, the heat exchanger b10, and the heat exchange tube b20 inside the multi-stage fluidized bed 9 are connected in sequence by pipelines.

[0051] The heating medium flowing in the heat exchange tube b20 in the multi-stage fluidized bed 9 is CO2. The room-temperature CO2 exchanges heat with the high-temperature CaCO3 at the solid particle discharge port of the multi-stage fluidized bed 9 and the high-temperature CO2 at the gas outlet, and then enters the heat exchange tube b20 to further obtain the heat generated by the exothermic reaction in the reactor, thereby reaching a temperature of 850°C, which can be used for power generation and heat supply subsequently.

[0052] In the high-throughput concentrated solar endothermic reaction unit, the high-temperature CO2 generated by the decomposition reaction of CaCO3 in the inclined plate moving bed 2 is heat-exchanged with the air through the matching heat exchanger a4, thereby realizing heat recovery; the fan a3, the heat exchange tube a of the CaO silo a15, the heat exchanger a4 and the heat exchange tube a of the CaCO3 silo a14 are connected in sequence by pipelines to form an air circulation.

[0053] The system of the present invention is based on solar heat collection drive The reversible chemical reaction, when sunlight is sufficient, maximizes heat recovery from the reaction products through multiple heat exchanges within a sealed endothermic reaction unit. Simultaneously, a vacuum pump continuously extracts the CO2 generated within the reactor, maintaining it at a low partial pressure and ensuring the reaction continues in the forward direction. At night or when sunlight is insufficient, the CaO particles generated by the endothermic reaction are transported to the CaO silo of the exothermic reaction unit and used as a reactant. Heat generated by the reaction is recovered through heat exchangers and heat exchange tubes within the multi-stage fluidized bed. This invention allows for energy storage during periods of sufficient sunlight and energy release at night or when sunlight is insufficient, ensuring an uninterrupted, all-weather heat supply. It can also increase reaction temperature and energy utilization.

[0054] The specific working process of the system of the present invention is:

[0055] When sunlight is sufficient, in the endothermic reaction unit, CaCO3 particles enter the inclined plate moving bed 2. Directly illuminated by sunlight reflected from the concentrator 1, they absorb heat and decompose into high-temperature CaO particles and high-temperature CO2. To maximize heat recovery from the reaction products, the system is equipped with a heat exchanger a4, and heat exchange tubes a are installed in the CaO silo a15 and the CaCO3 silo a14. Cool air delivered from fan a3 exchanges heat with the high-temperature CaO particles produced by the reaction in the CaO silo a15. The heated air is then transported to the heat exchanger a4, where it exchanges heat with the high-temperature CO2 produced by the reaction. The fully heated air is then delivered to the heat exchange tube a of the CaCO3 silo a14, where it is used to preheat the CaCO3 particles at the solid particle inlet of the reactor, accelerating the reaction and raising the reaction temperature, fully utilizing the heat generated by the reaction. At the same time, since all links of the entire system are closed, a vacuum pump 6 is set at the gas outlet of the reactor to continuously extract the CO2 generated in the reactor, so that the reactor has a certain vacuum degree, and the CO2 is always in a low partial pressure state in the reactor, thereby ensuring that the reaction continues; a cooler 5 is set between the reactor and the vacuum pump, and the CO2 preliminarily cooled by the heat exchanger a4 is transported to the cooler 5 for further cooling to a temperature that meets the normal operation of the vacuum pump.

[0056] At night or when there is insufficient sunlight, in the exothermic reaction unit, CaO particles and CO2 enter the multi-stage fluidized bed 9 from the solid particle feed port and the gas inlet respectively to react, generating high-temperature CaCO3 particles and a large amount of heat. In order to recover this heat, the system is equipped with a heat exchanger b10, a heat exchanger c11, and a CaO silo b16 and a CaCO3 silo b17 with heat exchange tubes inside, and a uniformly staggered heat exchange tube b20 is set inside the multi-stage fluidized bed. First, CO2 is selected as the heating medium. The room temperature CO2 enters the CaCO3 silo b17 to exchange heat with the high-temperature CaCO3 particles generated by the reaction. The heated medium is transported to the heat exchanger b10 to exchange heat with the high-temperature CO2 at the gas outlet of the reactor. The further heated medium is sent to the heat exchange tube b20 inside the multi-stage fluidized bed to recover the heat generated by the reaction. After being fully heated to 850°C, it flows out and can be used for power generation and heat supply later. Secondly, the high-temperature CO2 preliminarily cooled by the heat exchanger b10 is transported to the heat exchange tube a of the CaO silo b16 to preheat the CaO particles at the solid particle inlet of the reactor, accelerate the reaction and increase the reaction temperature, and make full use of the heat generated by the reaction. Finally, the further cooled CO2 is transported to the heat exchanger c11 to exchange heat with the low-temperature CO2 sent from the CO2 cylinder b13. After being fully cooled, it is sent to the gas inlet of the multi-stage fluidized bed 9 and is evenly distributed by the wind hood 21 into the reaction chamber for reaction.

[0057] In the entire thermochemical energy storage system, when there is sufficient sunlight, the CaO particles produced by the endothermic reaction are stored in the CaO silo a15 and subjected to heat exchange cooling there. At night or when there is insufficient light, the CaO particles in the CaO silo a15 are transported to the CaO silo b16 as reactants for the exothermic reaction. Similarly, at night or when there is insufficient light, the CaCO3 particles in the exothermic reaction are stored in the CaCO3 silo b17 and subjected to heat exchange cooling there. When there is sufficient sunlight, the CaCO3 particles in the CaCO3 silo b17 are transported to the CaCO3 silo a14 as reactants for the endothermic reaction. That is, when the system is driven by solar heat collection, the CaO particles in the CaCO3 silo b17 are transported to the CaCO3 silo a14 as reactants for the endothermic reaction. Solid particles can be recycled in a reversible chemical reaction.

[0058] Finally, it should be noted that the above embodiments are only preferred embodiments of the present invention to illustrate the technical solutions of the present invention, rather than limiting them, and certainly not limiting the patent scope of the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention. In other words, any changes or modifications that are made to the main design concept and spirit of the present invention without any substantive meaning, as long as the technical problems they solve are still consistent with the present invention, should be included in the protection scope of the present invention. In addition, the direct or indirect application of the technical solutions of the present invention in other related technical fields should also be included in the patent protection scope of the present invention.

Claims

1. A high-throughput solar thermochemical energy storage system based on reversible chemical reactions, characterized in that: It includes a solar concentrating device, a high-throughput concentrated solar endothermic reaction unit, an exothermic reaction unit and a reactant storage device; The solar concentrating device comprises a concentrator (1); The high-throughput concentrated solar endothermic reaction unit comprises an inclined plate moving bed (2), a fan a (3), a heat exchanger a (4), a cooler (5), a compressor (7) and a CO2 gas cylinder a (8); The exothermic reaction unit includes a multi-stage fluidized bed (9), a heat exchanger b (10), a heat exchanger c (11), a fan b (12) and a CO2 gas cylinder b (13); The reactant storage device includes a CaCO3 silo a (14), a CaCO3 silo b (17), a CaO silo a (15) and a CaO silo b (16); The solid outlet of the CaCO3 silo a (14) is connected to the feed port of the inclined plate moving bed (2), the discharge port of the inclined plate moving bed (2) is connected to the solid inlet of the CaO silo a (15), and the CO2 gas outlet of the inclined plate moving bed (2) is connected to the CO2 gas cylinder a (8) via the heat exchanger a (4), the cooler (5), and the compressor (7) in sequence; The concentrator (1) is used to concentrate sunlight onto the inclined plate moving bed (2), and the CaCO3 solid particles inside the inclined plate moving bed (2) complete a chemical reaction by absorbing heat; An air circulation is formed through pipelines between the air outlet of the fan a (3), the air inlet and air outlet of the CaO silo a (15), the air inlet and air outlet of the heat exchanger a (4), the air inlet and air outlet of the CaCO3 silo a (14), and the air inlet of the fan a (3); The solid outlet of the CaO silo a (15) is connected to the solid inlet of the CaO silo b (16), the solid outlet of the CaO silo b (16) is connected to the feed port of the multi-stage fluidized bed (9), the discharge port of the multi-stage fluidized bed (9) is connected to the solid inlet of the CaCO3 silo b (17), and the solid outlet of the CaCO3 silo b (17) is connected to the solid inlet of the CaCO3 silo a (14); The gas inlet of the CaCO3 silo b (17) is connected to a low-temperature heating medium, and the gas outlet of the CaCO3 silo b (17) is connected to the heating medium inlet of the multi-stage fluidized bed (9) through the heat exchanger b (10), and the heating medium outlet of the multi-stage fluidized bed (9) outputs a high-temperature working medium; The gas outlet of the multi-stage fluidized bed (9), the heat exchanger b (10), the gas inlet and gas outlet of the CaO silo b (16), the high-temperature side inlet of the heat exchanger c (11), the fan b (12), the CO2 gas cylinder b (13), the low-temperature side inlet of the heat exchanger c (11) and the gas inlet of the multi-stage fluidized bed (9) are connected in sequence by pipelines to form a CO2 circulation.

2. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 1 is characterized in that: A quartz window (18) for transmitting sunlight is provided on the top of the inclined plate type moving bed (2).

3. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 1 is characterized in that: The multi-stage fluidized bed (9) is provided with three chambers therein. After the CaO solid particles in the CaO silo b (16) enter the first chamber, they overflow and flow into the second chamber and the third chamber in sequence.

4. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 1, characterized in that: The multi-stage fluidized bed (9) is internally provided with heat exchange tubes b (20) that are evenly and staggeredly arranged.

5. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 4 is characterized in that: The CaCO3 silo a (14), CaCO3 silo b (17), CaO silo a (15) and CaO silo b (16) are all provided with a heat exchange tube a (19) inside, and the port of the heat exchange tube a (19) is the gas inlet and outlet of each silo.

6. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 1, characterized in that: The gas inlet of the multi-stage fluidized bed (9) is provided with a wind cap (21).

7. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 1, characterized in that: The high-throughput concentrated solar endothermic reaction unit further comprises a vacuum pump (6), which is arranged between the cooler (5) and the compressor (7).

8. The high-throughput solar thermochemical energy storage system based on reversible chemical reaction according to claim 1, characterized in that: The energy storage materials CaCO3 particles and CaO particles in the reactant storage device are both modified calcium-based materials CaMM. The CaCO3 particles are composed of CaCO3, MgO and Ca2MnO4, and the CaO particles are composed of CaO, MgO and Ca2MnO4. The atomic molar ratio of Ca, Mn and Mg in the CaCO3 particles and CaO particles is 9:1:

1.

9. A high-throughput solar thermochemical energy storage method based on a reversible chemical reaction, based on the high-throughput solar thermochemical energy storage system based on a reversible chemical reaction according to any one of claims 1 to 8, characterized in that: When the sunshine condition is sufficient, in the endothermic reaction unit, the CaCO3 particles in the CaCO3 silo a (14) enter the inclined plate moving bed (2), are directly irradiated by the sunlight reflected by the concentrator (1), and are decomposed into high-temperature CaO particles and high-temperature CO2 by endothermic reaction. The cold air sent from the fan a (3) exchanges heat with the high-temperature CaO particles produced by the reaction in the CaO silo a (15). The heated air is further transported to the heat exchanger a (4) to exchange heat with the high-temperature CO2 produced by the reaction. The fully heated air is sent to the CaCO3 silo a (14) to preheat the CaCO3 particles at the feed port of the inclined plate moving bed (2). The CO2 preliminarily cooled by the heat exchanger a (4) is transported to the cooler (5) for further cooling, and is compressed by the compressor (7) and stored in the CO2 cylinder a (8). At night or when there is insufficient sunlight, in the exothermic reaction unit, CaO particles and CO2 enter the multi-stage fluidized bed (9) from the feed port and the gas inlet respectively to react, generating high-temperature CaCO3 particles and generating a large amount of heat. The low-temperature heating medium enters the CaCO3 silo b (17) to exchange heat with the high-temperature CaCO3 particles generated by the reaction. The heated medium is transported to the heat exchanger b (10) to exchange heat with the high-temperature CO2 at the gas outlet of the reactor. The further heated medium is sent to the multi-stage fluidized bed (9) to recover the heat generated by the reaction. The CO2 is fully heated to 850°C and then flows out, and can be used for power generation and heat supply. Secondly, the high-temperature CO2 initially cooled by the heat exchanger b (10) is transported to the CaO silo b (16) to preheat the CaO particles at the feed port of the multi-stage fluidized bed (9). Finally, the further cooled CO2 is transported to the heat exchanger c (11) to exchange heat with the low-temperature CO2 sent from the CO2 cylinder b (13). After being fully cooled, it is sent to the gas inlet of the multi-stage fluidized bed (9) and then to the reaction chamber of the multi-stage fluidized bed (9) for reaction.

10. The high-throughput solar thermochemical energy storage method based on reversible chemical reaction according to claim 9, characterized in that: When there is sufficient sunlight, the CaO particles produced by the endothermic reaction are stored in the CaO silo a (15) and subjected to heat exchange and cooling there. At night or when there is insufficient sunlight, the CaO particles in the CaO silo a (15) are transported to the CaO silo b (16) to be used as reactants for the exothermic reaction. Similarly, at night or when there is insufficient sunlight, the CaCO3 particles produced by the exothermic reaction are stored in the CaCO3 silo b (17) and subjected to heat exchange and cooling there. When there is sufficient sunlight, the CaCO3 particles in the CaCO3 silo b (17) are transported to the CaCO3 silo a (14) to be used as reactants for the endothermic reaction.

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