Solar thermal power generation system based on annular solid heat storage system

Abstract

The utility model discloses a solar thermal power generation system based on an annular solid heat storage system, which comprises a solar heat collection system, the solar heat collection system is connected with the annular solid heat storage system to form a loop, and the annular solid heat storage system is connected with a steam generator to form a loop. The steam generator is connected with the power generation mechanism to form a loop; wherein the annular solid heat storage system comprises an annular pipeline, the water collector is connected to the annular pipeline through n water collection bypass pipelines which are connected in parallel, and the water distributor is connected to the annular pipeline through n water distribution bypass pipelines which are connected in parallel; and the annular solid heat storage system is used for determining the connection and disconnection of each water collection bypass pipeline and each water distribution bypass pipeline according to the flow of the heat exchange fluid entering the water collector in real time. The power generation system solves the problem that the outlet temperature stability of an existing solid heat storage system for solar thermal power generation is poor.

Description

[Technical Field]

[0001] This utility model belongs to the field of thermal energy utilization technology, specifically relating to a solar thermal power generation system based on a ring-shaped solid thermal storage system. [Background Technology]

[0002] Solar thermal power generation technology converts solar energy into heat energy for power generation. Solar radiation intensity is affected by various factors such as time, weather, and environment, exhibiting significant diurnal fluctuations. These variations in irradiance directly affect the inlet and outlet temperatures of the heat exchange fluid within the collector tubes, thus impacting the system's power generation efficiency and stability. To maintain the stability of the heat exchange fluid's inlet and outlet temperatures, combining the solar thermal power generation system with a thermal storage system can significantly smooth out system heat load fluctuations, maintain stable heat exchange fluid inlet and outlet temperatures, and improve the overall operating efficiency and stability of the solar thermal power generation system.

[0003] Currently, thermal storage systems used for solar thermal power generation include molten salt thermal storage and solid thermal storage systems. Compared with molten salt thermal storage, solid thermal storage systems have a significant disadvantage in terms of outlet temperature stability due to the presence of a thermocline. However, due to the huge advantages of solid thermal storage in terms of manufacturing cost, system operation and maintenance, and safety, it has great potential to replace molten salt as the mainstream thermal storage technology.

[0004] Due to the significant advantages of solid thermal storage in terms of manufacturing cost, system operation and maintenance, and safety, most thermal storage systems currently used for solar thermal power generation are solid thermal storage systems. However, due to the presence of thermoclines, solid thermal storage systems have certain disadvantages in terms of outlet temperature stability. [Utility Model Content]

[0005] The purpose of this invention is to provide a solar thermal power generation system based on a ring-shaped solid thermal storage system to solve the problem of poor outlet temperature stability in existing solid thermal storage systems for solar thermal power generation.

[0006] The present invention adopts the following technical solution: a solar thermal power generation system based on a ring solid thermal storage system, comprising a solar thermal collector system, the solar thermal collector system being connected to a ring solid thermal storage system to form a loop, the ring solid thermal storage system being connected to a steam generator to form a loop, and the steam generator being connected to a power generation mechanism to form a loop.

[0007] The annular solid thermal energy storage system includes:

[0008] A ring-shaped pipeline with n solid thermal storage modules connected in series evenly, where n≥2; each solid thermal storage module has valves installed at both the inlet and outlet ends.

[0009] A water collector has its inlet connected to the solar thermal system and the steam generator, and its outlet is connected in parallel to n water collection bypass pipes. Each water collection bypass pipe is connected to a position on the ring pipe between two adjacent solid thermal storage modules.

[0010] A water distributor has its outlets connected to the solar thermal collector system and the steam generator, and its inlet is connected in parallel to n water distribution bypass pipes. Each water distribution bypass pipe is connected to a position on the ring pipe between two adjacent solid thermal storage modules.

[0011] Among them, the annular solid thermal storage system is used to determine the on / off state of each water collection bypass pipe and each water distribution bypass pipe based on the real-time flow rate of the heat exchange fluid entering the water collector.

[0012] Furthermore, the ratio of the flow rate of the heat exchange fluid entering the water collector to the flow rate of a single solid thermal storage module is the number of open water collection bypass pipes, and also the number of open water distribution bypass pipes.

[0013] Furthermore, the various water collection bypass pipes are evenly arranged about the center of the ring pipe, and the various water distribution bypass pipes are evenly arranged about the center of the ring pipe.

[0014] Furthermore, the steam generator includes a superheater, a steam evaporator, and a preheater connected in sequence. The superheater is connected to a water distributor, and the preheater is connected to a water collector.

[0015] Furthermore, the power generation mechanism includes a turbine, the turbine inlet is connected to a superheater, the turbine outlet is connected to a preheater, and the turbine output shaft is coaxially connected to the generator input shaft.

[0016] The beneficial effects of this utility model are as follows: A ring-shaped solid thermal energy storage system is used to store solar heat. The ring-shaped solid thermal energy storage system is equipped with a water collector, a water distributor, and multiple parallel water collection bypass pipes and multiple water distribution bypass pipes. Independent valves are installed on each pipe. The number of circulating water collection bypass pipes and water distribution bypass pipes can be adjusted according to changes in the total flow rate of the heat exchange medium entering the water collector, ensuring that the flow rate entering the ring-shaped solid thermal energy storage system always matches the total flow rate. This addresses the changes in the inlet and outlet temperatures of the heat exchange fluid inside the heat collector tubes caused by variations in solar radiation intensity, thus solving the problem of poor outlet temperature stability in solid thermal energy storage systems for solar thermal power generation. [Attached Image Description]

[0017] Figure 1 This is a schematic diagram of the structure of the solar thermal power generation system based on the annular solid thermal storage system of this utility model;

[0018] Figure 2This is a schematic diagram of the annular solid thermal energy storage system of this utility model;

[0019] Figure 3 for Figure 2 Side view.

[0020] Among them, 1. Ring pipeline, 2. Solid thermal storage module, 3. Water collector, 4. Water collection bypass pipeline, 5. Water distributor, 6. Water distribution bypass pipeline, 7. Steam generator, 71. Superheater, 72. Steam evaporator, 73. Preheater, 8. Power generation mechanism, 81. Turbine, 82. Generator, 9. Solar thermal collection system.

Detailed Implementation Methods

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0022] This invention provides a solar thermal power generation system based on a ring-shaped solid thermal storage system, such as... Figure 1 As shown, it includes a solar thermal collector system 9, which is connected to an annular solid thermal storage system to form a loop, for storing solar energy in the annular solid thermal storage system; the annular solid thermal storage system is connected to a steam generator 7 to form a loop, and the steam generator 7 is connected to a power generation mechanism 8 to form a loop, for transferring the thermal energy stored in the annular solid thermal storage system to the power generation mechanism 8 for power generation through heat exchange;

[0023] like Figure 2 and Figure 3 As shown, the annular solid thermal energy storage system includes:

[0024] A ring-shaped pipeline 1 is connected in series with n solid thermal storage modules 2, where n≥2; each solid thermal storage module 2 is equipped with valves at both the inlet and outlet ends.

[0025] A water collector 3 has its inlet connected to the output pipes of the solar thermal system 9 and the steam generator 7, and its outlet is connected in parallel to n water collection bypass pipes 4. Each water collection bypass pipe 4 is connected to the ring pipe 1 at a position between two adjacent solid thermal storage modules 2. Each water collection bypass pipe 4 is equipped with a valve for controlling its on / off state.

[0026] A water distributor 5 has its outlet connected to the output pipes of the solar thermal collector system 9 and the steam generator 7, respectively. Its inlet is connected in parallel to n water distribution bypass pipes 6. Each water distribution bypass pipe 6 is connected to a position on the ring pipe 1 between two adjacent solid thermal storage modules 2. Each water distribution bypass pipe 6 is equipped with a valve to control its on / off state. Each water collection bypass pipe 4 and each water distribution bypass pipe 6 are not directly connected.

[0027] Among them, the annular solid thermal storage system is used to determine the on / off state of each water collection bypass pipe 4 and each water distribution bypass pipe 6 based on the real-time flow rate of the heat exchange fluid entering the water collector 3.

[0028] The ring-shaped arrangement of a ring-type solid thermal energy storage system offers greater flexibility in space utilization and future capacity expansion. If it is necessary to increase the system's thermal storage or power generation capacity, simply add more solid thermal energy storage modules to the ring and adjust the bypass piping accordingly. Each module operates independently, and in the event of a fault, it can be isolated without affecting overall operation, thus improving the system's maintainability and reliability.

[0029] In some embodiments, the ratio of the flow rate of the heat exchange fluid entering the water collector 3 to the flow rate of a single solid thermal storage module 2 is the number of open water collection bypass pipes 4 and also the number of open water distribution bypass pipes 6.

[0030] In some embodiments, the connected water collection bypass pipes 4 are evenly arranged about the center of the ring pipe 1, and the connected water distribution bypass pipes 6 are evenly arranged about the center of the ring pipe 1.

[0031] In some embodiments, the steam generator 7 includes a superheater 71, a steam evaporator 72, and a preheater 73 connected in sequence. The superheater 71 is connected to the water distributor 5, and the preheater 73 is connected to the water collector 3.

[0032] In some embodiments, the power generation mechanism 8 includes a turbine 81, the inlet of which is connected to a superheater 71, the outlet of which is connected to a preheater 73, and the output shaft of the turbine 81 is coaxially connected to the input shaft of the generator 82.

[0033] The present invention discloses a method for using a solar thermal power generation system based on a ring-shaped solid thermal storage system. The method involves inputting a high-temperature heat exchange medium heated by solar energy into the ring-shaped solid thermal storage system through a solar collector system 9 for heat storage, and then exchanging the heat in the ring-shaped solid thermal storage system with the power generation mechanism 8 through a steam generator 7 to generate electricity.

[0034] Among them, the ring solid thermal storage system can store heat and release heat. Its specific usage method is as follows: According to the ratio between the total flow rate of the input heat exchange fluid and the flow rate of each solid thermal storage module 2, the ratio is rounded to the integer m. Then, m water collection bypass pipes 4 are uniformly selected to simultaneously input the heat exchange fluid into the ring pipe 1.

[0035] The heat exchange fluid on the annular pipe 1 enters each solid thermal storage module 2 in the same direction, such as clockwise or counterclockwise, to exchange heat.

[0036] When the temperature of a certain solid thermal storage module 2 reaches the preset value, the flow of heat exchange fluid in the annular pipeline 1 can be stopped by the valve at its outlet, thereby controlling the start and stop of thermal storage or heat release operations.

[0037] This novel annular solid thermal energy storage system, through the coordination of a water collector, a water distributor, and multiple bypass pipes, can adjust the flow rate of each thermal energy storage module in real time according to changes in the flow rate of the heat exchange fluid, thereby better controlling the stability of the system's outlet temperature. The more stable the temperature, the higher the heat exchange efficiency of the steam generator, and the more stable the operation of the power generation equipment. When solar radiation intensity fluctuates, the flow rate of the heat exchange fluid changes accordingly. By adjusting the number and location of the bypass pipes and valves in the annular solid thermal energy storage system, a certain outlet temperature can be maintained when solar radiation weakens or excess heat can be quickly absorbed when radiation increases, significantly improving the system's ability to cope with changes in radiation.

[0038] Solid thermal energy storage systems offer greater safety and stability compared to molten salt systems, which suffer from the risk of large-scale fluid leakage and do not cause the high corrosion or maintenance costs associated with molten salt systems. Stable temperature control allows turbines and other power generation equipment to operate continuously at optimal parameters, improving overall power generation efficiency. Solid thermal energy storage also boasts lower material costs and a simpler system structure, requiring less routine maintenance. Compared to molten salt systems, solid thermal energy storage avoids large-scale molten salt leaks and scaling, resulting in lower overall operational safety risks and reduced impacts on power generation efficiency from downtime maintenance. Ring-shaped solid thermal energy storage systems can be combined with various equipment such as steam generators, turbines, and generators to meet diverse thermodynamic cycle needs. Whether it's smoothing power output, achieving peak shaving and frequency regulation, or adapting to different regional meteorological conditions, this system demonstrates strong feasibility and adaptability.

Claims

1. A solar thermal power generation system based on a toroidal solid heat storage system, characterized in that, The solar heat collecting system (9) is connected with a ring-shaped solid heat storage system and forms a loop, the ring-shaped solid heat storage system is connected with a steam generator (7) and forms a loop, and the steam generator (7) is connected with a power generating mechanism (8) and forms a loop. The ring-shaped solid heat storage system comprises: A ring-shaped pipeline (1) uniformly connected with n solid heat storage modules (2) in series, n≥2; the inlet and outlet of each solid heat storage module (2) are provided with valves; A water collector (3) with an inlet communicated with the solar heat collecting system (9) and the steam generator (7) respectively, and an outlet connected with n water collecting bypass pipelines (4) in parallel, each water collecting bypass pipeline (4) connected to the ring-shaped pipeline (1) at a position between two adjacent solid heat storage modules (2); A water distributor (5) with an outlet communicated with the solar heat collecting system (9) and the steam generator (7) respectively, and an inlet connected with n water distributing bypass pipelines (6) in parallel, each water distributing bypass pipeline (6) connected to the ring-shaped pipeline (1) at a position between two adjacent solid heat storage modules (2); The ring-shaped solid heat storage system is used for determining the on-off of each water collecting bypass pipeline (4) and each water distributing bypass pipeline (6) according to the flow rate of heat exchange fluid entering the water collector (3) in real time.

2. A solar thermal power system based on a toroidal solid thermal storage system as claimed in claim 1, wherein, The ratio of the flow rate of heat exchange fluid entering the water collector (3) to the flow rate of a single solid heat storage module (2) is the number of conducting water collecting bypass pipelines (4) and the number of conducting water distributing bypass pipelines (6).

3. A solar thermal power system based on a toroidal solid thermal storage system as claimed in claim 2, wherein, Each conducting water collecting bypass pipeline (4) is uniformly arranged about the center of the ring-shaped pipeline (1), and each conducting water distributing bypass pipeline (6) is uniformly arranged about the center of the ring-shaped pipeline (1).

4. A solar thermal power system based on a toroidal solid thermal storage system according to any one of claims 1-3, characterized in that, The steam generator (7) comprises a superheater (71), a steam evaporator (72) and a preheater (73) connected in sequence, the superheater (71) is communicated with the water distributor (5), and the preheater (73) is communicated with the water collector (3).

5. A solar thermal power system based on a toroidal solid thermal storage system as claimed in any one of claims 1 to 3, wherein, The power generating mechanism (8) comprises a turbine (81), the inlet of the turbine (81) is communicated with the superheater (71), the outlet of the turbine (81) is communicated with the preheater (73), and the output shaft of the turbine (81) is coaxially connected to the input shaft of a generator (82).

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