Fluidized reaction process of calcium-based heat storage material

Abstract

The application discloses a fluidized reaction process of calcium-based heat storage material. The fluidized reaction process of the calcium-based heat storage material comprises the following steps: S1: under the blowing of airflow, a solid mixture of inert solid particles and the calcium-based heat storage material is allowed to reversibly react in a fluidized bed reactor to obtain material A; the inert solid particles are A-type particles which do not participate in the reversible reaction of the calcium-based heat storage material, the mass percentage of the inert solid particles in the solid mixture is 55-90%, and the airflow comprises fluidized gas which does not participate in the reversible reaction of the calcium-based heat storage material; S2: the material A is fed into a cyclone separator, the inert solid particles in the material A are separated and fed back into the fluidized bed reactor. The application greatly improves the fluidization effect of calcium-based heat storage material Ca(OH)2 / CaO powder, improves the conversion rate and cycle performance of the calcium-based heat storage material, improves the exothermic reaction temperature, and the heat production quality is higher.

Description

Technical Field

[0001] This invention specifically relates to a fluidized bed reaction process for calcium-based thermal storage materials. Background Technology

[0002] The development of energy storage and thermal energy storage technologies has become a key research direction, with calcium-based thermal energy storage being a particularly popular area. Calcium-based thermal energy storage involves heating and decomposing Ca(OH)₂ to produce CaO and H₂O, converting thermal energy into chemical energy for storage. In use, the heat is released by the reaction of CaO and H₂O, which can then be used to generate steam to power a steam turbine for electricity generation or other applications.

[0003] Calcium-based thermal energy storage offers advantages such as suitable reaction conditions, high thermal density, and relatively low cost, making it a suitable reaction system for industrial application. This system possesses high energy density and suitable storage temperature, showing broad application prospects in solar thermal utilization and industrial waste heat recovery. Therefore, scholars both domestically and internationally have conducted extensive research on this system. Currently, most publicly reported devices utilize fixed-bed reactors, such as chemical heat pumps based on the Ca(OH)₂ / CaO system. In practical applications, to achieve commercial viability, the Ca(OH)₂ / CaO thermal energy storage system must reach a certain load, requiring the fixed-bed reactor to reach a certain scale. However, fixed-bed reactors suffer from problems such as large size, uneven heat exchange, and large operating pressure drop. Compared to fixed beds, fluidized beds offer advantages such as high mass and heat transfer efficiency, uniform temperature, and relative ease of scale-up, making fluidized bed technology a promising application option.

[0004] The decomposition of Ca(OH)₂ and the synthesis of CaO are gas-solid reactions. Generally, for gas-solid reactions, smaller solid particle size results in a larger specific surface area and a higher reaction rate. Therefore, reducing the size of Ca(OH)₂ / CaO is beneficial for the reaction. Commercially available Ca(OH)₂ powder is generally small, around 30 micrometers or less. Particles in this size range belong to Class C particles, which are prone to agglomeration. In fluidized beds, this leads to channeling of the gas, making stable fluidization difficult. Even when using larger Ca(OH)₂ / CaO powder as the reaction medium, initial fluidization may be good, but as fluidization progresses, frequent collisions between solid particles and the walls, internal surfaces, and between particles themselves cause significant particle wear due to the relatively low mechanical strength of Ca(OH)₂ / CaO. This leads to a rapid decrease in the average particle size and a rapid deterioration of the fluidization effect. Therefore, there is an urgent need for a fluidization reaction process suitable for Ca(OH)₂ / CaO powder to improve its reactivity. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of existing fluidization processes for calcium-based thermal storage materials, such as easy particle agglomeration, easy channeling, and difficulty in forming steady-state fluidization. This invention provides a fluidization reaction process for calcium-based thermal storage materials. The fluidization reaction process of this invention significantly improves the fluidization effect of calcium-based thermal storage materials (e.g., Ca(OH)₂ / CaO powder), increases the conversion rate and cycle performance of calcium-based thermal storage materials, raises the exothermic reaction temperature, and results in higher heat generation quality.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This invention provides a fluidized bed reaction process for calcium-based thermal storage materials, comprising the following steps:

[0008] S1: A solid mixture of inert solid particles and calcium-based thermal storage material undergoes a reversible reaction in a fluidized bed reactor under the influence of airflow to obtain material A; the inert solid particles are type A particles that do not participate in the reversible reaction of the calcium-based thermal storage material, and the inert solid particles account for 55-90% of the mass percentage in the solid mixture; the airflow includes fluidizing gas that does not participate in the reversible reaction of the calcium-based thermal storage material.

[0009] S2: Material A enters the cyclone separator, where the inert solid particles in Material A are separated and returned to the fluidized bed reactor.

[0010] According to Geldart's classification of solid particles, based on the average particle size and the density difference between the gas and solid phases, solid particles can be divided into the following four categories: Geldart A (aerated particles), Geldart B (bubbling particles), Geldart C (sticky particles), and Geldart D (overly coarse particles).

[0011] To further refine the transition boundaries between different types of particles and consider the balance of forces between particles, Baeyens et al. provided formulas for the transition boundaries between different types of particles:

[0012] d C-A =10325 / (ρ s -ρ g ) 0.725

[0013] d A→B =907200 / (ρ s -ρ g ) 1.17

[0014] d B→D =266300 / (ρ s -ρ g ) 0.807

[0015] In this invention, the Class A particles are the Geldart Class A particles as described above, which generally satisfy the following formula: 10325 / (ρ s -ρ g ) 0.725 ≤d≤907200 / (ρ s -ρ g ) 1.17 Where d is the average particle size in μm; ρ s -ρ g The density difference between the gas and solid phases is kg / m³. 3 .

[0016] In some preferred embodiments of the present invention, the inert solid particles are mineral particles in which component A accounts for not less than 90% by mass, and component A is silicon dioxide and / or aluminum oxide; more preferably, it is quartz sand.

[0017] In some preferred embodiments of the present invention, the particle size D of the inert solid particles is... 32 The preferred size is 100–300 μm, the more preferred size is 110–250 μm, and the even more preferred size is 180–250 μm.

[0018] In this invention, when the calcium-based thermal storage material is CaO, the temperature of the reversible reaction is preferably 470–500°C, and more preferably 480–490°C.

[0019] Preferably, the feed temperature of the CaO can be conventional in the art, preferably 200-600°C, for example 550°C.

[0020] Ca(OH)2 powder decomposes at a relatively high temperature to generate CaO. After a short period of heat preservation and storage, the CaO powder enters a fluidized bed reactor. The CaO powder entering the fluidized bed reactor carries a certain temperature, which enables the reaction to start up quickly and reach the temperature of the preferred reversible reaction mentioned above.

[0021] Preferably, the inlet temperature of the airflow is not less than 250°C, and more preferably not less than 300°C.

[0022] When the calcium-based thermal storage material is CaO, the gas flow includes reactive gas (water vapor) and non-reactive fluidizing gas. The preferred CaO feed temperature and inlet gas temperature ensure that CaO and water vapor undergo a hydration reaction upon contact, releasing heat to heat the system to the temperature of the reversible reaction. The heat released during the continued reaction is carried away by the heat exchange tubes within the bed.

[0023] For the reaction of CaO and H2O to synthesize Ca(OH)2, the conversion rate decreases with increasing operating temperature. However, if the reaction temperature is too high, the conversion rate decreases significantly, and the heat load on the reactor also decreases. Conversely, if the reaction temperature is too low, the quality of the heat released by the reaction deteriorates, reducing its utilization value. The reaction of calcium oxide with water to synthesize calcium hydroxide is a reversible reaction, and the relationship between its equilibrium temperature and pressure is shown in the following equation:

[0024] According to this formula, when the partial pressure of water vapor is 1 atmosphere, the equilibrium reaction temperature is approximately 505℃. Therefore, the reaction temperature cannot exceed 505℃. The higher the reaction temperature, the longer the conversion time required. The size of the reactor is related to the conversion time of the particles. Therefore, to ensure that the reactor size is within a reasonable range while ensuring the quality of the exothermic reaction, the reaction temperature under normal pressure is generally selected as 450℃.

[0025] The fluidization effect is greatly improved and the reaction rate is increased by incorporating inert solid particles into the fluidization process of this invention. The reaction temperature of this invention can be increased to a level of 470°C or higher, with a preferred reaction temperature of 480-490°C.

[0026] In this invention, the calcium-based thermal storage material is Ca(OH)2, and the temperature of the reversible reaction is preferably 500-600℃, more preferably 530-570℃, and even more preferably 550℃.

[0027] The decomposition equilibrium temperature at normal pressure is 505℃. The higher the temperature, the faster the decomposition reaction rate. However, excessively high temperatures can lead to particle deformation and a decrease in cycle performance. The preferred temperature for the above-mentioned reversible reaction in this invention ensures that the decomposition reaction has a certain rate while minimizing deformation of the heat storage material, thus extending its cycle life. Furthermore, it does not require a high-performance heat source, resulting in lower heat source costs.

[0028] For the fluidized system with the addition of the aforementioned inert fluidized solid particles, the inert solid particles serve as an intermediate heat transfer medium, making the Ca(OH)2 powder more dispersed and heated more uniformly. This effectively reduces the problem of decreased activity caused by the reduction in porosity of calcium hydroxide due to uneven heat transfer and local overheating. At the same time, the more efficient heat transfer also allows the reaction to proceed rapidly at the aforementioned lower temperatures, which reduces the cost of the heat source and extends the service life of the Ca(OH)2 powder.

[0029] In this invention, the calcium-based thermal storage material can be a conventional material in the art that utilizes reversible chemical reactions for thermal storage and release, preferably Ca(OH)2 or CaO.

[0030] Those skilled in the art will conventionally understand that when the calcium-based thermal storage material is Ca(OH)2, the reaction occurring in the fluidized bed reactor is an endothermic decomposition reaction of Ca(OH)2 to generate CaO and H2O; when the calcium-based thermal storage material is CaO, the reaction occurring in the fluidized bed reactor is a reaction of CaO and H2O to generate Ca(OH)2 and release heat.

[0031] In this invention, preferably, when the calcium-based thermal storage material is CaO, the inert solid particles account for 60-75% of the mass percentage of the solid mixture, for example, 70%.

[0032] In this invention, preferably, when the calcium-based thermal storage material is Ca(OH)2, the inert solid particles account for 55-80% of the mass percentage of the solid mixture, more preferably 65-75%, for example 70%.

[0033] In this invention, the fluidizing gas can be conventional in the art, and preferably N2.

[0034] In this invention, when the calcium-based thermal storage material is CaO, the gas also includes water vapor.

[0035] The water vapor accounts for a volume percentage of not less than 80% in the gas, and more preferably not less than 90%.

[0036] In this invention, when the calcium-based thermal storage material is Ca(OH)2, the gas flow may also include water vapor. Preferably, the volume percentage of water vapor in the gas is not higher than 20%, more preferably not higher than 10%.

[0037] In this invention, preferably, the cyclone separator can only separate the inert solid particles, while the calcium-based thermal storage material and its reaction products cannot be separated. More preferably, the dividing diameter of the cyclone separator is 60-80 μm.

[0038] The segmentation diameter refers to the diameter at which 50% of the particles can be removed after passing through the cyclone separator.

[0039] In this invention, those skilled in the art will understand that when the calcium-based thermal storage material is Ca(OH)2, the material A includes CaO, water vapor, the fluidizing gas, and the inert solid particles.

[0040] In this invention, those skilled in the art will understand that when the calcium-based thermal storage material is CaO, the material A includes Ca(OH)2, water vapor, the fluidizing gas, and the inert solid particles.

[0041] In this invention, preferably, the material B discharged from the dust-laden gas outlet of the cyclone separator enters a bag filter for gas-solid separation to obtain solid powder C and gas D.

[0042] Those skilled in the art will understand that when the calcium-based thermal storage material is Ca(OH)2, when the material B includes CaO, water vapor and the fluidizing gas, the solid powder C includes CaO, and the gas D includes water vapor and the fluidizing gas.

[0043] Those skilled in the art will understand that when the calcium-based thermal storage material is CaO, when the material B includes Ca(OH)2, water vapor and the fluidizing gas, the solid powder C includes Ca(OH)2, and the gas D includes water vapor and the fluidizing gas.

[0044] The bag filter dust collector preferably has a capture efficiency of ≥99% for particles with a diameter of 1 micrometer; the operating pressure of the bag filter dust collector is preferably ≤1.5 kPa.

[0045] Preferably, the gas separated by the bag filter enters the condenser, where it is condensed and liquefied to separate water vapor and fluidized gas.

[0046] Preferably, when the calcium-based thermal storage material is Ca(OH)2, the solid powder separated by the bag filter enters the degassing tank and the water vapor in the solid powder is replaced by nitrogen.

[0047] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0048] The reagents and raw materials used in this invention are all commercially available.

[0049] The positive and progressive effects of this invention are as follows: The fluidization reaction process of the calcium-based thermal storage material significantly improves the fluidization effect of Ca(OH)2 / CaO powder, enabling steady-state fluidization of Class A particles; the calcium-based thermal storage material has a high conversion rate, with both the initial exothermic and storage processes achieving a conversion rate of over 85%; the calcium-based thermal storage material exhibits good cycle performance, is not prone to agglomeration, and shows minimal particle size variation, maintaining an average conversion rate of over 80% after 50 cycles; it can increase the exothermic reaction temperature to 480–490°C, exceeding the 450°C temperature of ordinary CaO exothermic reactions, resulting in higher exothermic quality; and it has a high reaction rate, with small particles exhibiting high specific surface area, good heat and mass transfer performance, and a high reaction rate. Detailed Implementation

[0050] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0051] The CaO used in the following embodiments and comparative examples of this invention was produced by Lingshou County Weixin Mineral Products Processing Plant, with a particle size D. 32 The material is 13μm CaO with a purity of 95%; the Ca(OH)2 material is obtained by synthesizing CaO with water; all other raw materials are commercially available.

[0052] Example 1

[0053] Quartz sand is used as the inert solid particles, and CaO powder is used as the calcium-based thermal storage material. The particle size D of the quartz sand is... 32 The fluidization results of the solid mixture with different inert solid particle addition ratios (100–200 μm) for varying the mass ratio of quartz sand and CaO powder are shown in Table 1.

[0054] Table 1. Effect of Quartz Sand Addition Ratio on Fluidization Effect

[0055]

[0056] Therefore, when the calcium-based thermal storage material is CaO, if the SiO2 addition ratio is less than 50%, the solid mixture is still prone to channeling and it is difficult to form steady-state fluidization; when the SiO2 addition ratio is increased to more than 60%, the fluidized bed is in a state between bubbling and turbulent bed, forming steady-state fluidization.

[0057] Quartz sand is used as the inert solid particles, and the calcium-based thermal storage material is Ca(OH)2 powder obtained by the reaction of CaO. The particle size D of the quartz sand is... 32 The fluidization results of the solid mixture with different inert solid particle addition ratios (100–200 μm) for varying the mass ratio of quartz sand and CaO powder are shown in Table 2.

[0058] Table 2 Effect of Quartz Sand Addition Ratio on Fluidization Effect

[0059]

[0060]

[0061] As shown in Table 2, when the calcium-based thermal storage material is Ca(OH)2, the solid mixture is still prone to channeling and difficult to form steady-state fluidization when the addition ratio of quartz sand is less than 50%. When the addition ratio of quartz sand is increased to 55%, the fluidized bed is in a bubbling bed state. When the addition ratio of quartz sand is increased to 70%, the fluidized bed is in a state between a bubbling bed and a turbulent bed state, which is a better fluidization state.

[0062] Quartz sand was used as the inert solid particles, and CaO powder was used as the calcium-based thermal storage material. The mass ratio of calcium-based thermal storage material to SiO2 was 3:7, and the particle size D32 of the calcium-based thermal storage material was <10μm. The effect of different quartz sand particle sizes on the fluidization results is shown in Table 3 below:

[0063] Table 3. Influence of different quartz sand particle sizes on fluidization results.

[0064]

[0065] As can be seen from Table 3, when the particle size D32 of the inert solid particles is ≤80μm, the solid powder is prone to channeling in the fluidized bed and it is difficult to form a steady fluidization. When the particle size D32 of the inert solid particles reaches 110μm, the calcium-based thermal storage material reaches the bubbling bed state. When the particle size D32 of the inert solid particles reaches 180μm or more, the calcium-based thermal storage material reaches a stable fluidization state between the bubbling bed and the turbulent bed.

[0066] Example 2

[0067] Exothermic process: Inert solid granular quartz sand is added through the solid feed inlet of the fluidized bed reactor. The particle size D of the quartz sand is... 32 A 100–200 μm particle size is used to assist in the fluidization of CaO powder. A mixture of H₂O / N₂ (volume ratio 90:10) is added through the gas inlet, controlling the apparent gas velocity in the reaction bed to 0.3 m / s, fluidizing the quartz sand particles. Then, CaO powder is added through the solid inlet, with a mass ratio of quartz sand to CaO powder of 65:35. At this point, the fluidization state of the quartz sand and CaO powder is between bubbling and turbulence. During the initial operation, the quartz sand can be preheated through heat exchange tubes. The inlet temperature of the mixed gas is 300℃. When the fluidized bed is in a fluidized state between bubbling and turbulence, the CaO powder added through the solid inlet reacts with water vapor, releasing heat to heat the system to 480–490℃. The heat released during the continued reaction is carried away by the heat exchange tubes within the reaction bed. The released heat is then removed through the heat exchange tubes at the bottom. Part of the quartz sand and the generated Ca(OH)₂ powder are blown into a cyclone separator by an airflow. Larger quartz sand particles in the cyclone separator flow out through the dust outlet and are transported back to the reaction bed of the fluidized bed reactor. The remaining Ca(OH)₂ powder and airflow enter a baghouse dust collector for gas-solid separation. The baghouse dust collector has a capture efficiency of ≥99% for particles with a diameter of 1 micrometer, and its operating pressure is ≤1.5 kPa. Ca(OH)₂ powder is obtained from the dust outlet of the baghouse dust collector; the gas from the gas outlet enters a condenser, where water vapor and fluidized bed gas N₂ are separated through condensation and liquefaction.

[0068] Thermal storage process: Inert solid quartz sand with a particle size of 100–300 μm is added through the solid feed inlet of the fluidized bed reactor to assist in the fluidization of Ca(OH)₂ powder. During the initial operation, the quartz sand bed is heated to 500°C using a heating medium within the heat exchange tubes of the fluidized bed reactor. When the reaction bed temperature reaches above 400°C, Ca(OH)₂ powder generated during the exothermic process is added through the solid feed inlet. The average particle size of the Ca(OH)₂ powder is D. 32 The particle size is 16 μm. The mass ratio of quartz sand to Ca(OH)₂ is 7:3. Nitrogen is used as the fluidizing gas, with an apparent velocity of 0.1 m / s relative to the reaction bed. The gas enters the fluidized bed reactor through the gas inlet, causing the fluidization morphology of the Ca(OH)₂ powder and quartz sand in the reaction bed to be between bubbling and turbulence. The reaction bed is continuously heated through heat exchange tubes, maintaining a temperature of 550℃. The Ca(OH)₂ powder decomposes, producing calcium oxide and water vapor. The generated products move upwards along with the quartz sand. As the diameter of the fluidized bed reactor increases, the flow velocity decreases. Since the quartz sand is larger in size and density, most of it falls back to the bottom of the bed. A small portion, along with the generated calcium oxide and water vapor, enters the cyclone separator to separate the larger quartz sand particles. These larger particles then re-enter the bed through the bottom feed leg to continue heat exchange and fluidization within the bed. The generated CaO, water vapor, and fluidizing gas enter a downstream bag filter for gas-solid separation. The operating pressure of the bag filter is ≤1.5 kPa. The CaO powder obtained from the dust outlet of the bag filter enters a degassing tank, where nitrogen is used to replace the water vapor in the solid powder. The mixed gas obtained from the gas outlet of the bag filter enters a condenser, where the water vapor and fluidizing gas N2 are condensed and separated.

[0069] In the first round of operation, the conversion rate of the calcium-based thermal storage material reached over 85% in both the exothermic and thermal storage processes, with no particle agglomeration. After 10 cycles, the average conversion rate did not decrease significantly, remaining at around 82%. After 50 cycles, the average conversion rate was still above 80%. Due to the small particle size of the powder itself, although some wear or breakage occurred during fluidization, the overall particle size distribution did not change significantly after the wear and breakage reached equilibrium. Therefore, after multiple cycles, the fluidization quality within the bed did not decrease significantly, and the reaction conversion rate remained at a high level.

[0070] Comparative Example 1

[0071] Comparative Example 1 used a fixed-bed reactor with a diameter of 0.1 m and a height of 0.5 m. The bed consisted of untreated CaO powder, and the heat exchange medium passed through the tube bundle. During the synthesis reaction stage, steam was introduced at the bottom of the reactor. Calcium oxide particles in the fixed bed reacted with the steam, releasing heat, while the heat exchange medium passed through the tube bundle to remove heat. The synthesis reaction temperature was 300°C. During the heat storage stage, high-temperature flue gas was introduced into the tube bundle. Calcium hydroxide in the bed was heated to form calcium oxide and release steam. The generated steam was discharged from the top exhaust pipe. The operating temperature was 600°C. After the first round of reaction, the average conversion rate was approximately 80%, with significant particle agglomeration. Continuing operation, due to particle agglomeration, the heat transfer efficiency decreased significantly, and the conversion rate decreased markedly. After 10 cycles, the conversion rate dropped to 30%.

[0072] Comparative Example 2

[0073] The only difference between Comparative Example 2 and Example 2 is that no inert solid particles of quartz sand are added.

[0074] Without the addition of inert particles, the fluidization of the calcium-based thermal storage material is very poor, exhibiting obvious localized channeling. During this process, due to the continuous channeling of steam, the particles in the bed cannot flow out smoothly. Therefore, the reactor can only be operated intermittently; that is, a certain amount of CaO / Ca(OH)₂ is first added to the reactor, and then the solid feed inlet is closed. During the exothermic process, most of the introduced water vapor flows out of the reactor directly without contacting the calcium oxide particles. After 1 hour of reaction, sampling tests showed that the average conversion rate of the particles in the bed was only 23%. For the thermal storage process, calcium hydroxide particles are filled into the bed, and electric heating rods are used for heating, with the heating power controlled at 2.1 W / cm². 2 Due to poor fluidization within the bed, most particles remained stationary, resulting in excessively high temperatures for particles in direct contact with the heating rod, while particles further away from the heating rod remained at lower temperatures, failing to reach the decomposition temperature. After 1 hour of operation, bed particles were analyzed, revealing an average calcium hydroxide conversion rate of approximately 17%. Furthermore, near the heating rod, the generated calcium hydroxide exhibited caking due to excessively high temperatures.

[0075] Without the addition of inert particles, poor fluidization within the bed leads to uneven heat and mass transfer, resulting in low conversion rates and consequently reduced heat storage and release density. Furthermore, poor fluidization causes operational instability, making continuous reactor operation difficult.

[0076] Comparative Example 3

[0077] Comparative Example 3 employed a continuous fluidized bed reactor with large particles of an average diameter of 100 micrometers, utilizing a high-pressure drop distributor provided by SCHWING Technologies GmbH to achieve relatively stable fluidization of CaO / Ca(OH)2. The synthesis stage was conducted at 450°C, while the decomposition stage was heated by an electric heating rod, maintaining a temperature of 560°C. After the first cycle, product analysis showed that the conversion rates in both the synthesis and decomposition stages were above 85%. With increasing cycle count, significant wear and breakage of the CaO / Ca(OH)2 particles occurred, resulting in a marked decrease in the average particle size and a decline in both fluidization efficiency and conversion rate within the bed. After 10 cycles, the average particle size within the bed decreased to 43 micrometers, and the average conversion rate decreased by 62%. To restore bed fluidization, a portion of the powder was discarded, and fresh large-particle raw materials were added accordingly, resulting in approximately 10 effective cycles for Comparative Example 3.

[0078] Meanwhile, the particles selected in Comparative Example 3 were larger in size, had a smaller specific surface area, a slower reaction rate, and required a longer time for the heat storage and exothermic processes.

Claims

1. A fluidized bed reaction process for a calcium-based thermal storage material, characterized in that, It includes the following steps: S1: A solid mixture comprising inert solid particles and calcium-based thermal storage material is subjected to a reversible reaction of the calcium-based thermal storage material in a fluidized bed reactor under the agitation of an airflow to obtain material A; the inert solid particles are type A particles that do not participate in the reversible reaction of the calcium-based thermal storage material, and the inert solid particles account for 55-90% of the mass percentage of the solid mixture; the airflow includes fluidizing gas that does not participate in the reversible reaction of the calcium-based thermal storage material. The inert solid particles are mineral particles in which component A accounts for not less than 90% by mass, and component A is silicon dioxide and / or aluminum oxide; the calcium-based thermal storage material is Ca(OH)2 or CaO; The particle size D of the inert solid particles 32 The range is 100~300μm; When the calcium-based thermal storage material is CaO, the apparent gas velocity in the reaction bed section of the fluidized bed reactor is 0.1-0.5 m / s; When the calcium-based thermal storage material is Ca(OH)2, the apparent gas velocity in the reaction bed section of the fluidized bed reactor is 0.1-0.3 m / s; S2: Material A enters the cyclone separator, which separates the inert solid particles in Material A and returns the inert solid particles to the fluidized bed reactor.

2. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, The inert solid particles are quartz sand; And / or, the particle size D of the inert solid particles 32 The value is 110~250μm.

3. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 2, characterized in that, The particle size D of the inert solid particles 32 It is 180~250μm.

4. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, When the calcium-based thermal storage material is CaO, the inert solid particles account for 60-75% of the mass percentage of the solid mixture. Alternatively, when the calcium-based thermal storage material is Ca(OH)2, the inert solid particles account for 55-80% of the mass percentage of the solid mixture.

5. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 4, characterized in that, When the calcium-based thermal storage material is CaO, the inert solid particles account for 70% of the mass percentage of the solid mixture. Alternatively, when the calcium-based thermal storage material is Ca(OH)2, the inert solid particles account for 65-75% of the mass percentage of the solid mixture.

6. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 5, characterized in that, When the calcium-based thermal storage material is Ca(OH)2, the inert solid particles account for 70% of the mass percentage of the solid mixture.

7. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, When the calcium-based thermal storage material is CaO, the feed temperature of CaO is 200~600℃; When the calcium-based thermal storage material is CaO, the inlet temperature of the airflow is not lower than 250°C.

8. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 7, characterized in that, When the calcium-based thermal storage material is CaO, the feed temperature of CaO is 550℃; When the calcium-based thermal storage material is CaO, the inlet temperature of the airflow is not lower than 300°C.

9. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, When the calcium-based thermal storage material is CaO, the temperature of the reversible reaction is 470~500℃; The calcium-based thermal storage material is Ca(OH)2, and the temperature of the reversible reaction is 500~600℃.

10. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 9, characterized in that, When the calcium-based thermal storage material is CaO, the temperature of the reversible reaction is 480~490℃; The calcium-based thermal storage material is Ca(OH)2, and the temperature of the reversible reaction is 530~570℃.

11. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 10, characterized in that, The calcium-based thermal storage material is Ca(OH)2, and the temperature of the reversible reaction is 550℃.

12. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, When the calcium-based thermal storage material is CaO, the airflow also includes water vapor; And / or, the fluidizing gas is N2; And / or, when the calcium-based thermal storage material is Ca(OH)2, the volume percentage of water vapor in the airflow is not higher than 20%.

13. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 12, characterized in that, When the calcium-based thermal storage material is CaO, the water vapor accounts for no less than 80% of the volume percentage in the airflow; And / or, when the calcium-based thermal storage material is Ca(OH)2, the volume percentage of water vapor in the gas flow is not higher than 10%.

14. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 13, characterized in that, When the calcium-based thermal storage material is CaO, the volume percentage of water vapor in the airflow is not less than 90%.

15. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, When the calcium-based thermal storage material is CaO, the apparent gas velocity in the reaction bed section of the fluidized bed reactor is 0.3 m / s.

16. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, The cyclone separator has a segmentation diameter of 60~80μm.

17. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 1, characterized in that, Material B discharged from the dust-laden gas outlet of the cyclone separator enters the bag filter for gas-solid separation.

18. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 17, characterized in that, The bag filter has a capture efficiency of ≥99% for particles with a diameter of 1 micrometer; the operating pressure of the bag filter is ≤1.5 kPa.

19. The fluidized bed reaction process for the calcium-based thermal storage material as described in claim 17 or 18, characterized in that, When the calcium-based thermal storage material is Ca(OH)2, the solid powder separated by the bag filter enters the degassing tank and the water vapor in the solid powder is replaced by nitrogen. And / or, the gas separated by the bag filter enters the condenser, where it is condensed and liquefied to separate water vapor and fluidized gas.

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