Thermochemical energy storage gas-solid reaction system cylindrical fixed bed reactor and testing method thereof

Abstract

The invention provides a cylindrical fixed bed reactor of a thermochemical energy storage gas-solid reaction system and a testing method thereof, and belongs to the field of thermochemical energy storage. According to the invention, the heat storage and release cycle experiment can be carried out for different thermochemical gas-solid reaction systems, especially the heat storage and release process of a hydroxide system and a hydrated salt system. Openings at two ends of a reaction cavity are respectively connected with a top seal head and a bottom seal head, the top seal head is provided with an air inlet, the bottom seal head is provided with an air outlet, and stainless steel sintered plates are respectively arranged between the air inlet and the reaction cavity and between the air outlet and the reaction cavity; the heat exchange cavity is embedded in the periphery of the reaction cavity, a cooling water coil and a heating pipe are arranged in the heat exchange cavity, an inlet and an outlet of the cooling water coil are connected with a cooling water coil inlet and a cooling water coil outlet in the heat exchange cavity respectively, and positive and negative binding posts of the heating pipe extend out of the heat exchange cavity. According to the invention, heat storage and release performance research under various working conditions of variable temperature, variable pressure and variable flow can be carried out.

Description

Technical Field

[0001] This invention belongs to the field of thermochemical energy storage, and in particular relates to a cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system and its testing method. Background Technology

[0002] Thermal energy storage technology plays a significant role in enabling cross-seasonal energy storage and long-distance transportation, and improving the utilization rate and stability of renewable energy. Thermal energy storage technologies are mainly divided into three types: sensible heat storage, latent heat storage, and thermochemical energy storage. Thermochemical energy storage is based on a reversible reaction that converts thermal energy into the chemical potential energy of the storage material, realizing the heat storage / release process during the endothermic / exothermic chemical reaction. During energy storage, reactants absorb heat, and products are stored separately; when heat is needed, reactants are mixed under certain conditions to release heat. Compared to sensible heat and phase change heat storage, thermochemical energy storage technology has the highest heat storage density, enabling long-term thermal energy storage and long-distance transportation, with almost no heat loss during the storage and release processes. Based on these advantages, thermochemical energy storage technology is considered one of the most promising technologies, with broad application prospects in concentrated solar power plants, industrial waste heat recovery, and urban combined heat and power (CHP). However, because thermochemical energy storage technology is more complex than the other two types, its technological maturity is lower, and it is currently still in the laboratory stage, requiring significant research investment.

[0003] There are three main types of reactors for thermochemical energy storage systems: fixed-bed reactors, moving-bed reactors, and fluidized-bed reactors. Compared to the other two types, fixed-bed reactors have a simpler structure and lower manufacturing cost, and have been widely used in experimental research and actual production. However, research on thermochemical energy storage systems is currently still in the laboratory stage and has not yet been widely applied in industry and daily life. The main reasons for this are: the difficulty in understanding the influence of physical conditions on the reaction process, the need to explore the high-power and high-efficiency operating mode of the system, and the need to optimize strategies for improving the stability of the system's heat storage and release cycle. Therefore, it is necessary to design a reactor that can test the thermal performance of thermochemical energy storage materials under different conditions, conduct experimental research on the system's heat storage and release cycle under different operating conditions, explore the heat and mass transport and reaction conditions during system operation, clarify the influence of physical conditions on the reaction process, and provide experimental data support for the parameter setting and optimization design of thermochemical energy storage systems. Summary of the Invention

[0004] In view of this, to address the technical problems mentioned in the background section, this invention provides a cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system and its testing method. This reactor can conduct heat storage and release cycle experiments on different thermochemical gas-solid reaction systems, particularly the heat storage and release processes of hydroxide and hydrated salt systems. Furthermore, it can also be used to conduct experimental studies on the heat storage and release processes of different types of sensible heat storage materials and phase change heat storage materials. This fixed-bed reactor can solve the problems of single operating conditions and incomplete analysis of the heat storage and release performance of thermochemical reactors, providing strong support for the study of the working process of heat storage systems, the design of operating parameters, and the improvement of heat storage and release performance.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system, comprising a reaction chamber, a heat exchange chamber, a top end cap, a bottom end cap, a cooling water coil, and a heating tube. The openings at both ends of the reaction chamber are respectively connected to the top end cap and the bottom end cap. The top end cap is provided with an air inlet, and the bottom end cap is provided with an air outlet. Stainless steel sintered plates are respectively provided between the air inlet and the air outlet and the reaction chamber. The heat exchange chamber is nested around the reaction chamber and is provided with a cooling water coil and a heating tube inside. The heating tube is arranged longitudinally along the heat exchange chamber, and the cooling water coil is located on the outer periphery of the heating tube and is spirally arranged. A cooling water coil inlet is provided at one end of the heat exchange chamber, and a cooling water coil outlet is provided at the other end. The inlet and outlet of the cooling water coil are respectively connected to the cooling water coil inlet and cooling water coil outlet on the heat exchange chamber. The positive and negative terminals of the heating tube extend to the outside of the heat exchange chamber.

[0006] Furthermore, the top end cap and the bottom end cap are fixed together by screw flanges and sealed by graphite gaskets.

[0007] Furthermore, the reaction chamber is filled with a solid thermal storage material.

[0008] Furthermore, the thermochemical energy storage gas-solid reaction system cylindrical fixed-bed reactor also includes a pressure gauge, which is installed on the top end cap.

[0009] Furthermore, the cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system also includes a three-point thermocouple, which is installed on the top end cap and used to detect the reaction temperature inside the reaction chamber.

[0010] Furthermore, the reaction chamber is a cylinder, and the heat exchange chamber is an annular cylinder.

[0011] Furthermore, the reaction chamber, top end cap, bottom end cap, cooling water coil, and heating pipe are all made of high-temperature and corrosion-resistant metal materials.

[0012] Furthermore, the heat exchange cavity is made of a metal material with high thermal conductivity, high temperature resistance, and corrosion resistance.

[0013] Furthermore, the cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system is wrapped with thermal insulation material.

[0014] A test method for a cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system. In thermal storage mode, the heating tube is activated by the electric heating control cabinet, and the heating temperature and temperature rise rate are intelligently regulated. The heating tube transfers heat to the reactants in the reaction chamber to cause decomposition reaction. The generated gaseous products are discharged through the gas outlet and collected. During the thermal storage reaction, the gas pressure in the reaction chamber is displayed by the pressure gauge, and the temperature data in the reaction chamber is collected by the three-point thermocouple. Finally, the heat storage, thermal storage power and thermal storage efficiency of the system are calculated and analyzed by the heating temperature, exhaust gas temperature and gas flow data. In heat release mode, the gas participating in the reaction is driven by a steam generator to enter the reaction chamber through the inlet. The gas flow rate and pressure are intelligently controlled. After entering the reaction chamber, the gas reacts chemically with the solid reactants and releases heat. Heat exchange fluid is introduced into the cooling water coil through the cooling water coil inlet, so that heat exchange occurs between the reaction chamber and the heat exchange chamber. The heat exchange fluid that has absorbed heat is discharged from the heat exchange chamber through the cooling water coil outlet. During the heat release process, the gas pressure in the reaction chamber is displayed by a pressure gauge, and the temperature data in the reaction chamber is collected by a three-point thermocouple. Finally, the heat release, heat release power, and heat release efficiency of the reaction system are calculated and analyzed by the inlet flow rate, heat exchange fluid flow rate, and temperature difference between the cooling water coil inlet and outlet. Compared with existing technologies, the beneficial effects of the cylindrical fixed-bed reactor and its testing method for a thermochemical energy storage gas-solid reaction system described in this invention are: 1. The cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system described in this invention can be used for thermal cycle research of various gas-solid thermochemical heat storage materials, phase change heat storage materials and sensible heat storage materials.

[0015] 2. The heat exchange chamber of the cylindrical fixed-bed reactor in the thermochemical energy storage gas-solid reaction system of the present invention can realize both electric heating and cooling heat exchange functions, and achieve both heat storage and heat release operation modes with a relatively compact structure.

[0016] 3. The cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system described in this invention is simple to fill with reaction materials and easy to disassemble and install. The reaction chamber and heat exchange chamber are easy to combine and separate, and the reactor is easy to maintain and transport.

[0017] 4. The cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system described in this invention can be used to study the heat storage and release performance under various operating conditions such as variable temperature, variable pressure and variable flow rate.

[0018] 5. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system described in this invention can provide an experimental device for testing and analyzing the thermal properties of thermal storage materials, experimentally studying the influence of operating conditions, and optimizing the strategy of system heat storage and release cycle. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system described in this invention; Figure 2 This is a schematic diagram of the internal structure of the reaction chamber described in this invention; Figure 3 This is a schematic diagram of the overall structure of the heat exchange cavity described in this invention; Figure 4 This is a schematic diagram of the cooling water coil structure described in this invention; Figure 5 This is a schematic diagram of the heating tube structure described in this invention.

[0020] In the diagram: 1. Reaction chamber; 2. Heat exchange chamber; 3. Top end cap; 4. Bottom end cap; 5. Cooling water coil; 6. Heating tube; 7. Screw flange; 8. Graphite gasket; 9. Air inlet; 10. Air outlet; 11. Stainless steel sintered plate; 12. Cooling water coil inlet; 13. Cooling water coil outlet; 14. Positive and negative terminals of heating tube; 15. Pressure gauge; 16. Three-point thermocouple. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the drawings, and not all of them. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the invention.

[0022] See Figure 1-5This embodiment describes a cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system, comprising a reaction chamber 1, a heat exchange chamber 2, a top end cap 3, a bottom end cap 4, a cooling water coil 5, and a heating pipe 6. The openings at both ends of the reaction chamber 1 are connected to the top end cap 3 and the bottom end cap 4 respectively, secured by screw flanges 7 and sealed by graphite gaskets 8. The top end cap 3 has an air inlet 9, and the bottom end cap 4 has an air outlet 10. The air inlet 9 and the air outlet 10 are respectively positioned between themselves and the reaction chamber 1. Stainless steel sintered plate 11; heat exchange chamber 2 is nested around the reaction chamber 1, and is equipped with cooling water coil 5 and heating pipe 6 inside. The heating pipe 6 is arranged longitudinally along the heat exchange chamber 2 in a zigzag shape to increase the heating area. The cooling water coil 5 is located on the outer periphery of the heating pipe 6 and is spirally arranged to increase the cooling area. The inlet and outlet of the cooling water coil 5 are connected to the cooling water coil inlet 12 and cooling water coil outlet 13 on the heat exchange chamber 2, respectively. The positive and negative terminals 14 of the heating pipe 6 extend to the outside of the heat exchange chamber 2.

[0023] The cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system described in this embodiment uses a PID intelligent controller to regulate and display the flow rate, and an electric heating control cabinet to regulate and display the temperature, while also displaying the pressure and collecting pressure data.

[0024] In this embodiment, the reaction chamber 1 can be filled with various types of solid thermal storage materials. After the top end cap 3 or the bottom end cap 4 is separated from the reaction chamber 1, the material can be added through the openings at both ends of the reaction chamber 1.

[0025] The screw flange 7 and the graphite gasket 8 are used to create a sealed environment within the reaction chamber 1, preventing gas leakage during the reaction process and external gas from interfering with the reaction process.

[0026] The air inlet 9 can be used to add gaseous materials required for the heat release reaction, such as water vapor in the hydration reaction.

[0027] The gas outlet 10 is used to discharge and collect water vapor or other gaseous products generated by the decomposition of reactants during the thermal storage reaction process.

[0028] The stainless steel sintered plate 11 is used to filter the gas in the reaction chamber 1 and prevent powder material from clogging the air inlet 9 and the air outlet 10.

[0029] The cooling water coil 5 is made of corrosion-resistant and high-temperature resistant metal material. The cooling water coil 5 can be circulated with gas or liquid. The cooling water coil inlet 12 and the cooling water coil outlet 13 are connected to external equipment.

[0030] The heating tube 6 is made of corrosion-resistant and high-temperature resistant metal material. The heating tube 6 can provide the temperature required for the reaction in the reaction chamber 1. The positive and negative terminals 14 of the heating tube are connected to the external electric heating control cabinet.

[0031] Specific Implementation Plan Two: Combining Figure 1-5 This embodiment describes a thermochemical energy storage gas-solid reaction system cylindrical fixed-bed reactor, which also includes a pressure gauge 15 mounted on the top end cap 3. Other components and connections are the same as in specific embodiment one.

[0032] Specific implementation plan three: combined with Figure 1-5 This embodiment further includes a cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system, comprising a three-point thermocouple 16 mounted on the top end cap 3. The three-point thermocouple 16 is used to detect the reaction temperature inside the reaction chamber 1, and data is collected in real time using a data acquisition instrument. Other components and connections are the same as in specific embodiment one.

[0033] Specific Implementation Plan Four: Combining Figure 1-5 This embodiment describes a thermochemical energy storage gas-solid reaction system with a cylindrical fixed-bed reactor. The reaction chamber 1 and heat exchange chamber 2 can be nested and disassembled. The reaction chamber 1 is cylindrical, and the heat exchange chamber 2 is annular. The outer diameter of the reaction chamber 1 matches the inner diameter of the heat exchange chamber 2. This design facilitates material addition and reactor transportation and maintenance. Other components and connections are the same as in specific embodiment one.

[0034] Specific implementation plan five: Combining Figure 1-5 In this embodiment, the reaction chamber 1, top end cap 3, bottom end cap 4, cooling water coil 5, and heating pipe 6 of the cylindrical fixed bed reactor of the thermochemical energy storage gas-solid reaction system described in this embodiment are all made of high-temperature and corrosion-resistant metal materials.

[0035] Specific implementation plan six: Combining Figure 1-5 This embodiment describes a thermochemical energy storage gas-solid reaction system in which the heat exchange chamber 2 of the cylindrical fixed-bed reactor is made of a metal material with high thermal conductivity, high temperature resistance, and corrosion resistance.

[0036] Specific implementation plan seven: Combining Figure 1-5 This embodiment describes a thermochemical energy storage gas-solid reaction system where the cylindrical fixed-bed reactor is surrounded by insulation material to reduce heat loss during operation and ensure operational safety and accuracy of measurement data. Specifically, the insulation material is used on the parts of the reactor that are in contact with the outside environment, namely the reaction chamber 1 and the heat exchange chamber 2. The inner surfaces of these two chambers that are in contact with each other are not covered with insulation material and are in direct contact.

[0037] The working principle of the cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system described in this invention is as follows: In thermal storage mode, the heating element 6 is activated via the electric heating control cabinet, allowing for intelligent control of the heating temperature and temperature rise rate. The heating element 6 transfers heat to the reactants in the reaction chamber 1, causing a decomposition reaction. The resulting gaseous products are discharged through the outlet 10 and collected. During the thermal storage reaction, the gas pressure in the reaction chamber 1 is displayed via pressure gauge 15, and the temperature data within the reaction chamber 1 is collected via three-point thermocouples 16. The system's heat storage capacity, thermal storage power, and thermal storage efficiency are calculated and analyzed using the heating temperature, exhaust gas temperature, and gas flow rate data.

[0038] In heat release mode, the gas participating in the reaction is driven by a steam generator to enter the reaction chamber 1 through the inlet 9. The gas flow rate and pressure can be intelligently controlled. After entering the reaction chamber 1, the gas reacts chemically with the solid reactants and releases heat. Heat exchange fluid is introduced into the cooling water coil 5 through the cooling water coil inlet 12, causing heat exchange between the reaction chamber 1 and the heat exchange chamber 2. The heat-absorbing fluid is discharged from the heat exchange chamber 2 through the cooling water coil outlet 13. During the heat release process, the gas pressure in the reaction chamber 1 is displayed by the pressure gauge 15, and the temperature data in the reaction chamber 1 is collected by the three-point thermocouple 16. The heat release, heat release power, and heat release efficiency of the reaction system are calculated and analyzed using the inlet flow rate, heat exchange fluid flow rate, and the temperature difference between the cooling water coil inlet and outlet.

[0039] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating orientation and positional relationships are based on the orientation and positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0040] The embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A cylindrical fixed-bed reactor for a thermochemical energy storage gas-solid reaction system, characterized in that: The reaction chamber includes a reaction chamber (1), a heat exchange chamber (2), a top end cap (3), a bottom end cap (4), a cooling water coil (5), and a heating pipe (6). The openings at both ends of the reaction chamber (1) are connected to the top end cap (3) and the bottom end cap (4), respectively. The top end cap (3) is provided with an air inlet (9), and the bottom end cap (4) is provided with an air outlet (10). Stainless steel sintered plates 11 are provided between the air inlet (9) and the air outlet (10) and the reaction chamber (1), respectively. The heat exchange chamber (2) is nested around the reaction chamber (1). The part is provided with a cooling water coil (5) and a heating tube (6). The heating tube (6) is arranged longitudinally along the heat exchange chamber (2). The cooling water coil (5) is located on the outer periphery of the heating tube (6) and is spirally arranged. A cooling water coil inlet (12) is provided at one end of the heat exchange chamber (2), and a cooling water coil outlet (13) is provided at the other end. The inlet and outlet of the cooling water coil (5) are respectively connected to the cooling water coil inlet (12) and the cooling water coil outlet (13) on the heat exchange chamber (2). The positive and negative terminals (14) of the heating tube (6) extend to the outside of the heat exchange chamber (2).

2. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The top end cap (3) and the bottom end cap (4) are fixed by a screw flange (7) and sealed by a graphite gasket (8).

3. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The reaction chamber (1) is filled with solid thermal storage material.

4. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The thermochemical energy storage gas-solid reaction system cylindrical fixed bed reactor also includes a pressure gauge (15), which is installed on the top end cap (3).

5. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system also includes a three-point thermocouple (16), which is installed on the top end cap (3) and used to detect the reaction temperature inside the reaction chamber (1).

6. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The reaction chamber (1) is a cylinder, and the heat exchange chamber (2) is an annular cylinder.

7. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The reaction chamber (1), top end cap (3), bottom end cap (4), cooling water coil (5), and heating pipe (6) are all made of high-temperature and corrosion-resistant metal materials.

8. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The heat exchange chamber (2) is made of a metal material with high thermal conductivity, high temperature resistance and corrosion resistance.

9. The cylindrical fixed-bed reactor for the thermochemical energy storage gas-solid reaction system according to claim 1, characterized in that: The cylindrical fixed-bed reactor of the thermochemical energy storage gas-solid reaction system is wrapped with thermal insulation material.

10. A test method for a cylindrical fixed-bed reactor of a thermochemical energy storage gas-solid reaction system as described in any one of claims 1-9, characterized in that: In the heat storage mode, the heating tube (6) is turned on by the electric heating control cabinet, and the heating temperature and temperature rise rate are intelligently controlled. The heating tube (6) transfers heat to the reactants in the reaction chamber (1) to undergo decomposition reaction. The generated gas products are discharged through the gas outlet (10) and collected. During the heat storage reaction, the gas pressure in the reaction chamber (1) is displayed by the pressure gauge (15). The temperature data in the reaction chamber (1) is collected by the three-point thermocouple (16). Finally, the heat storage, heat storage power and heat storage efficiency of the system are calculated and analyzed by the heating temperature, the discharged gas temperature and the gas flow data. In the heat release mode, the gas participating in the reaction is driven by the steam generator to enter the reaction chamber (1) through the air inlet (9). The gas flow rate and pressure are intelligently controlled. After the gas enters the reaction chamber (1), it reacts chemically with the solid reactants and releases heat. The heat exchange fluid is introduced into the cooling water coil (5) through the cooling water coil inlet (12) so that the reaction chamber (1) and the heat exchange chamber (2) exchange heat. The heat exchange fluid that absorbs heat is discharged from the heat exchange chamber (2) through the cooling water coil outlet (13). During the heat release process, the gas pressure in the reaction chamber (1) is displayed by the pressure gauge (15). The temperature data in the reaction chamber (1) is collected by the three-point thermocouple (16). Finally, the heat release, heat release power and heat release efficiency of the reaction system are calculated and analyzed by the air inlet flow rate, heat exchange fluid flow rate and the temperature difference between the cooling water coil inlet and the cooling water coil outlet.

Images