Liquid air energy storage power generation system and method

Abstract

The invention discloses a liquid air energy storage power generation system and method. The system comprises a compression filtering heat storage unit used for converting air into clean compressed air and recycling compressed heat energy; the energy storage unit is used for liquefying the clean compressed air through multi-stage cooling and storing liquid air; and the power generation unit is used for performing multi-stage heating on the pressurized liquid air to obtain gaseous pressurized air, recovering cold energy, and heating the gaseous pressurized air by using compressed heat energy so as to generate power. In the energy storage stage, surplus electric energy is stored as liquid air and compression heat energy is recycled, in the energy release stage, the liquid air is pressurized and then subjected to multi-stage heating and cold energy recycling, the compression heat energy recycled in the energy storage stage is used for heating again, then power generation is conducted, energy exchange from electric energy to compression heat is achieved, and the energy conversion efficiency is improved. The electric energy utilization rate and the system stability are improved, the defects of intermittency and randomness of renewable energy power generation are overcome, and meanwhile the utilization rate of cold energy is improved.

Description

Technical Field

[0001] The present invention belongs to the field of electric energy storage, and more specifically, relates to a liquid air energy storage power generation system and method. Background Art

[0002] With the growth of population and the development of industrialization, the conflict between the scale of power supply and the demand for electricity is becoming increasingly obvious. In particular, China currently mainly relies on thermal power, and the greenhouse gas emissions and environmental pollution caused by the use of fossil energy for power generation are increasingly attracting social attention. Although renewable energy power generation can greatly reduce greenhouse gas emissions and environmental pollution, its own uneven distribution, randomness and intermittency will cause power generation instability and insufficient power supply during peak hours. When the power grid fails, local areas will fall into a power supply crisis, causing problems in safety, production and people's livelihood. A stable and reliable energy storage system can effectively make up for the shortcomings of renewable energy itself, and the development of such energy storage systems has significant engineering significance.

[0003] Liquid air energy storage technology is a technical means to improve the stability of the power grid. Liquid air energy storage technology uses surplus electricity to compress liquid air during low electricity consumption and store electricity in the form of liquid air; during peak electricity consumption, the liquid air is gasified, expanded to generate electricity, and the energy in the liquid air is released to fill the electricity demand during peak electricity consumption, avoiding the problem of unstable power generation of renewable energy. At the same time, liquid air is an environmentally harmless, geographically unrestricted energy storage medium with high energy storage density. In summary, this energy storage and power generation method makes up for the shortcomings of randomness and intermittency in renewable energy power generation, and can stabilize fluctuations and cut peaks and fill valleys. However, liquid air energy storage technology is still in its infancy, the technology is not mature, and related technologies still need to be further explored and improved. The present invention provides an implementable, high-conversion-rate, stable and controllable liquid air energy storage system with broad engineering prospects.

[0004] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to those skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to propose a liquid air energy storage power generation system and method, which can realize the storage of surplus electrical energy as liquid air, and at the same time recover the compression heat energy generated by the compression process. In the energy release stage, the pressurized liquid air is cold recovered, and the compression heat energy recovered in the energy storage stage is used to heat the cold recovered gaseous pressurized air, so that the turbine unit can work and generate electricity, realizing the energy conversion from electrical energy to compression heat and then to electrical energy.

[0006] To achieve the above objectives, the present invention proposes a liquid air energy storage power generation system and method.

[0007] According to a first aspect of the present invention, a liquid air energy storage power generation system is proposed, comprising:

[0008] The compression filtering heat storage unit is used to compress air to obtain compressed air, and perform heat exchange between the compressed air and a heat storage medium to obtain the heat storage medium that absorbs heat; cool the compressed air that has completed the heat exchange and filter it to obtain clean compressed air, and compress the clean compressed air again to perform heat exchange with the heat storage medium again; store the compressed heat energy in the compressed air or the clean compressed air through the heat storage medium that absorbs heat; cool the clean compressed air that has completed the last heat exchange and then transport it to the energy storage unit;

[0009] An energy storage unit, used for liquefying the clean compressed air that has completed the cooling through multi-stage cooling to obtain liquid air and store it;

[0010] The power generation unit is used for, in the energy release stage, pressurizing the liquid air stored in the energy storage unit so that the liquid air is input into the power generation unit, and performing multi-stage heating on the pressurized liquid air through the cooling medium released during the cooling process of the compression filtration heat storage unit and the energy storage unit to obtain gaseous pressurized air; heating the gaseous pressurized air by using the compression heat energy stored in the heat storage medium that absorbs heat, and then generating electricity by using the heated gaseous pressurized air, and recovering cold energy during the multi-stage heating process through the cooling medium.

[0011] Optionally, the compression filtration heat storage unit comprises:

[0012] A plurality of compression heat exchange modules, wherein the plurality of compression heat exchange modules are connected in sequence, each of the compression heat exchange modules is used to compress the air or the compressed air output by the previous compression heat exchange module, and to perform heat exchange between the compressed air generated by each compression heat exchange module itself and the heat storage medium;

[0013] A cooling filter module is arranged between the plurality of compression and heat exchange modules, and is used to store a first cooling medium, and to perform heat exchange between the compressed air outputted by the compression and heat exchange module connected to the front stage of the cooling filter module and the first cooling medium, to obtain the first cooling medium that has been released and to store it; to filter the compressed air that has completed the heat exchange; and to transport the compressed air that has completed the filtration to the compression and heat exchange module connected to the rear stage of the cooling filter module for compression and heat exchange again;

[0014] A compression final stage water cooling module, the input end of the compression final stage water cooling module is connected to the output end of the last compression heat exchange module, and is used to cool the clean compressed air output by the last compression heat exchange module by cooling water;

[0015] The heat storage medium storage module is used to store the heat storage medium and the heat absorbing heat storage medium, and stores the compression heat energy by storing the heat absorbing heat storage medium.

[0016] Optionally, the energy storage unit includes:

[0017] A pre-cooling refrigeration module is used to perform heat exchange between the clean compressed air output by the compression filtration heat storage unit and the second cooling medium and the third cooling medium output by the liquefied cooling module, and store the released second cooling medium; perform expansion refrigeration on a part of the clean compressed air that has completed the heat exchange to obtain expanded air;

[0018] A liquefaction cooling module is used to perform heat exchange between another part of the clean compressed air that has completed the heat exchange and the fourth cooling medium and the third cooling medium to obtain the liquid air, and store the fourth cooling medium that has released cold; and to perform expansion, decompression and cooling on the liquid air output by the liquefaction module;

[0019] A liquid air storage module is used to store the liquid air that has completed the expansion and decompression cooling; the expanded air and the evaporated gas generated by the liquid air that has completed the expansion and decompression cooling form the third cooling medium, which is sequentially transported to the liquefied cooling module and the pre-cooling refrigeration module to respectively perform heat exchange with another part of the clean compressed air that has completed the heat exchange and the clean compressed air output by the compression, filtration and heat storage unit;

[0020] The input end of the liquefied cooling module is connected to the output end of the pre-cooling refrigeration module, the input end of the liquid air storage module is connected to the output end of the liquefied cooling module, the low-temperature and pressure-reduced air input end of the liquid air storage module is connected to the low-temperature and pressure-reduced air output end of the pre-cooling refrigeration module, the third cooling medium output end of the liquid air storage module is connected to the third cooling medium input end of the liquefied cooling module, and the third cooling medium output end of the liquefied cooling module is connected to the third cooling medium input end of the pre-cooling refrigeration module.

[0021] Optionally, the power generation unit comprises:

[0022] A pressurizing module, used for pressurizing the liquid air stored in the liquid air storage module and then transporting the pressurized liquid air to the first cold energy recovery module;

[0023] a first cold energy recovery module, configured to perform heat exchange between the released fourth cooling medium and the pressurized liquid air, heat the liquid air to obtain gaseous pressurized air, and recover cold energy in the liquid air through the released fourth cooling medium;

[0024] a second cold energy recovery module, configured to perform heat exchange between the second cooling medium that has released cold and the gaseous pressurized air, heat the gaseous pressurized air, and recover cold energy in the gaseous pressurized air through the second cooling medium that has released cold;

[0025] a third cold energy recovery module, used for performing heat exchange again between the first cooling medium that has released cold and the gaseous pressurized air that has completed the heat exchange, heating the gaseous pressurized air again, and recovering cold energy in the gaseous pressurized air again through the first cooling medium that has released cold;

[0026] A plurality of expansion power generation modules, each of which includes an air expansion preheating module and a power generation module, the output end of the air expansion preheating module is connected to the input end of the power generation module, and all the expansion power generation modules are connected in sequence;

[0027] The air expansion preheating module is used to perform heat exchange between the heat storage medium that absorbs heat and the gaseous pressurized air that has completed the multi-stage heating;

[0028] The power generation module is used to generate electricity through the gaseous pressurized air that has completed heat exchange in the air expansion preheating module;

[0029] The input end of the pressurizing module is connected to the output end of the liquid air storage module, the output end of the pressurizing module is connected to the input end of the first cold energy recovery module, the output end of the first cold energy recovery module is connected to the input end of the second cold energy recovery module, the output end of the second cold energy recovery module is connected to the input end of the third cold energy recovery module, and the output end of the third cold energy recovery module is connected to the input end of the first air expansion preheating module.

[0030] Optionally, the compression heat exchange module comprises:

[0031] A compression module, used to compress the air or re-compress the filtered clean compressed air;

[0032] A compression heat recovery module, used for performing heat exchange between the heat storage medium and the compressed air or the clean compressed air output by the compression module, and recovering the compression heat through the heat storage medium;

[0033] The output end of the compression module is connected to the input end of the compression heat energy recovery module.

[0034] Optionally, the cooling filtration module comprises:

[0035] A pre-filter cooling module, used for performing heat exchange between the compressed air output by the compression heat exchange module connected to the front stage of the pre-filter cooling module and the first cooling medium; the input end of the pre-filter cooling module is connected to the output end of the compression heat exchange module connected to the front stage;

[0036] A filter module is used to filter the compressed air output by the pre-filter cooling module to obtain the clean compressed air, and transmit the clean compressed air to the compression heat exchange module connected to the rear stage of the filter module for compression; the input end of the filter module is connected to the output end of the pre-filter cooling module, and the output end of the filter module is connected to the input end of the compression heat exchange module connected to the rear stage;

[0037] A cold first cooling medium storage module, used for storing the first cooling medium;

[0038] A hot first cooling medium storage module, used for storing the first cooling medium for cooling;

[0039] The cooling medium input end of the pre-filtration cooling module is connected to the output end of the cold first cooling medium storage module, the cooling medium output end of the pre-filtration cooling module is connected to the input end of the hot first cooling medium storage module, the cooling medium output end of the third cold energy recovery module is connected to the input end of the cold first cooling medium storage module, and the cooling medium input end of the third cold energy recovery module is connected to the output end of the hot first cooling medium storage module.

[0040] Optionally, the thermal storage medium storage module includes:

[0041] A cold thermal storage medium storage module, used for storing the thermal storage medium;

[0042] A thermal storage medium storage module for storing the thermal storage medium that absorbs heat;

[0043] The heat storage medium input end of the compression heat recovery module is connected to the output end of the cold heat storage medium storage module, the heat storage medium output end of the compression heat recovery module is connected to the input end of the hot heat storage medium storage module, the input end of the cold heat storage medium storage module is connected to the heat storage medium output end of the air expansion preheating module, and the output end of the hot heat storage medium storage module is connected to the heat storage medium input end of the air expansion preheating module. Optionally, the precooling refrigeration module includes:

[0044] The pre-cooling refrigeration module includes:

[0045] An air precooling module, used for performing heat exchange between the second cooling medium, the third cooling medium output by the liquefied cooling module and the clean compressed air output by the final compression water cooling module;

[0046] A cold second cooling medium storage module, used for storing the second cooling medium;

[0047] A hot second cooling medium storage module, used for storing the second cooling medium for cooling;

[0048] An air refrigeration expansion module, used for expanding and refrigerating a portion of the clean compressed air output by the air precooling module to obtain the expanded air;

[0049] The input end of the air precooling module is connected to the output end of the compression final stage water cooling module, the second cooling medium input end of the air precooler is connected to the output end of the cold second cooling medium storage module, the second cooling medium output end of the air precooling module is connected to the input end of the hot second cooling medium storage module, the input end of the cold second cooling medium storage module is connected to the cooling medium output end of the second cold energy recovery module, the output end of the hot second cooling medium storage module is connected to the cooling medium input end of the second cold energy recovery module, the input end of the air refrigeration expansion module is connected to the second output end of the air precooling module, and the output end of the air refrigeration expansion module is connected to the low-temperature decompression air input end of the liquid air storage module.

[0050] Optionally, the liquefaction module comprises.

[0051] an air liquefaction module, configured to perform heat exchange between the fourth cooling medium, the third cooling medium outputted by the liquid air storage module, and the clean compressed air outputted by the first output end of the air precooling module, so as to obtain the liquid air;

[0052] A cold fourth cooling medium storage module, used for storing the fourth cooling medium;

[0053] A hot fourth cooling medium storage module, used for storing the fourth cooling medium for cooling;

[0054] A liquid air expansion module, used for expanding, depressurizing and cooling the liquid air output by the air liquefaction module;

[0055] The input end of the air liquefaction module is connected to the first output end of the air precooling module, the cooling medium input end of the air liquefaction module is connected to the output end of the cold fourth cooling medium storage module, the cooling medium output end of the air liquefaction module is connected to the input end of the hot fourth cooling medium storage module, the input end of the cold fourth cooling medium storage module is connected to the cooling medium output end of the first cold energy recovery module, and the output end of the hot fourth cooling medium storage module is connected to the cooling medium input end of the first cold energy recovery module; the input end of the liquid air expansion module is connected to the output end of the air liquefaction module, and the output end of the liquid air expansion module is connected to the liquid air storage module.

[0056] According to a second aspect of the present invention, a liquid air energy storage power generation method is proposed, which is applied to the liquid air energy storage system described in any one of the first aspects, comprising:

[0057] In the energy storage stage, compressed air is obtained by compressing air, and the compressed air is heat exchanged with a heat storage medium to obtain the heat storage medium that absorbs heat; the compressed air that has completed the heat exchange is cooled and filtered to obtain clean compressed air, and the clean compressed air is compressed again to exchange heat with the heat storage medium again; the compressed heat energy in the compressed air or the clean compressed air is stored by the heat storage medium that absorbs heat; the clean compressed air that has completed the last heat exchange is cooled and transported to the energy storage unit;

[0058] liquefying the clean compressed air that has completed the cooling through multi-stage cooling to obtain liquid air and store it;

[0059] In the energy release stage, the liquid air stored in the energy storage unit is pressurized so as to be input into the power generation unit, and the pressurized liquid air is subjected to multi-stage heating by the cooling medium released during the cooling process of the compression filtration heat storage unit and the energy storage unit to obtain gaseous pressurized air; the gaseous pressurized air is heated by the compressed heat energy stored in the heat storage medium that absorbs heat, and then electricity is generated by the heated gaseous pressurized air, and cold energy is recovered during the multi-stage heating process by the cooling medium.

[0060] The beneficial effects of the present invention are as follows: the present invention stores surplus electric energy as liquid air in the energy storage stage, and recovers the compression heat energy generated in the compression process at the same time; in the energy release stage, the pressurized liquid air is cold recovered, the cold energy is recovered and the low-temperature cooling medium is regenerated; the compression heat energy recovered in the energy storage stage is used to heat the gaseous pressurized air that has been cold recovered to obtain high-temperature gaseous pressurized air, and then the power generation module generates electricity through the high-temperature gaseous pressurized air, thereby realizing the energy conversion from electric energy to compression heat energy and then to electric energy; the energy storage stage and the energy release stage of the present invention can be operated independently, and the energy release stage can be operated when the compressor unit is not started In the case of power grid fluctuations, the power generation can be independently completed through the heat source (compressed heat energy), which provides higher flexibility for the overall situation; the energy storage power generation system of the present invention is connected in parallel with the power grid to make up for the intermittent and random nature of renewable energy power generation, can stabilize fluctuations, and smooth out peaks and fill valleys, providing the ability to intervene when the power grid fluctuates to enable the power grid to generate stable power, thereby improving the energy utilization rate and system stability; at the same time, liquid air is an environmentally friendly, geographically unrestricted energy storage medium with a high energy storage density. Compared with traditional battery energy storage technology, the present invention has a higher storage density, a higher energy storage efficiency, and will not pollute the environment.

[0061] The system of the present invention has other characteristics and advantages, which will be apparent from the drawings incorporated herein and the following detailed description, or will be described in detail in the drawings incorporated herein and the following detailed description, which together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which like reference numerals generally represent like components.

[0063] Figure 1 A schematic diagram of a liquid air energy storage power generation system according to the present invention is shown.

[0064] Figure 2 A schematic diagram of a liquid air energy storage power generation system according to Example 1 of the present invention is shown.

[0065] Figure 3 A schematic diagram of a liquid air energy storage power generation system (including a liquid-air separation tank) according to Example 1 of the present invention is shown.

[0066] Figure 4 A flow chart showing the steps of a liquid air energy storage power generation method according to Example 2 of the present invention.

[0067] Description of reference numerals:

[0068] 1. Compressor, 2. Compression heat recovery device, 3. Compression end water cooler, 4. Molecular sieve pre-cooler, 5. Molecular sieve, 6. Hot molecular sieve cooling medium storage tank, 7. Cold molecular sieve cooling medium storage tank, 8. Molecular sieve post-heat exchanger, 9. Air precooler, 10. Air refrigeration expander, 11. Air liquefier, 12. Liquid air expansion valve, 13. Liquid-air separator tank, 14. Liquid-air storage tank, 15. Hot shallow cold medium storage tank, 16. Cold shallow cold medium storage tank, 17. Hot deep cold medium storage tank, 18. Cold deep cold medium storage tank, 19. Hot thermal storage medium storage module, 20. Cold thermal storage medium storage module, 21. Deep cold recovery device, 22. Shallow cold recovery device, 23. Air expansion preheater, 24. Turbine generator set, 25. Booster pump. DETAILED DESCRIPTION

[0069] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0070] like Figure 1 As shown, a liquid air energy storage power generation system according to the present invention comprises

[0071] The compression filtration heat storage unit is used to compress air to obtain compressed air, and perform heat exchange between the compressed air and the heat storage medium to obtain the heat storage medium that absorbs heat; the compressed air that has completed the heat exchange is cooled and filtered to obtain clean compressed air, and the clean compressed air is compressed again to perform heat exchange with the heat storage medium again; the compressed heat energy in the compressed air or clean compressed air is stored through the heat storage medium that absorbs heat; the clean compressed air that has completed the last heat exchange is cooled and then transported to the energy storage unit;

[0072] An energy storage unit is used to liquefy the clean compressed air that has been cooled through multi-stage cooling to obtain liquid air and store it;

[0073] The power generation unit is used to pressurize the liquid air stored in the energy storage unit during the energy release stage so that the liquid air is input into the power generation unit, and the pressurized liquid air is subjected to multi-stage heating by the cooling medium released during the compression and filtration heat storage unit and the cooling process of the energy storage unit to obtain gaseous pressurized air; the gaseous pressurized air is heated by the compression heat energy stored in the heat storage medium that absorbs heat, and then electricity is generated by the heated gaseous pressurized air, and cold energy is recovered by the cooling medium during the multi-stage heating process.

[0074] Specifically, the liquid air energy storage and power generation system of the present invention includes a compression, filtration and heat storage unit, an energy storage unit and a power generation unit. When electricity consumption is low, the electric energy is stored as liquid air through the compression, filtration and heat storage unit. This is the energy storage stage. The compression, filtration and heat storage unit first compresses the external air through electric energy to obtain high-temperature and high-pressure compressed air. After the pressure of the compressed air meets the inlet pressure requirement of the filtering equipment, the compressed air is filtered. The function of the filtration is to filter out the excessive water vapor and oil droplets contained in the compressed air coming out of the air source, as well as solid impurities such as rust, sand, pipe sealants, etc.; after the filtration is completed, the compression is continued until the pressure of the clean compressed air meets the process requirements. At the same time, during the compression process, the heat energy generated by the compression is stored through the heat storage medium, which is used to heat the compressed air in the energy release stage to make it expand and heat up. Energy is saved by utilizing the compressed heat energy; the clean compressed air is cooled in multiple stages by the energy storage unit, and then the clean compressed air is liquefied to obtain liquid air. The liquid air The temperature is very low, and needs to be cooled from about 60°C to -190°C. It is difficult for a cooling medium to remain liquid throughout this temperature span, so multiple cooling media are selected for multi-stage cooling. For example, two-stage cooling is adopted. The first stage uses the liquid first cooling medium and the relatively low-temperature flash air to preliminarily pre-cool the clean compressed air output by the compressed filtration heat storage unit, and then separates a part of the pre-cooled clean compressed air and expands and refrigerates it to supplement the third cooling medium (flash air) to supplement the cold capacity used to cool the clean compressed air; the second stage continues to reduce the temperature of the compressed air through the liquid second cooling medium and the third cooling medium with a lower temperature than the first cooling medium to liquefy it. After the third cooling medium completes the heat exchange in the second stage, the temperature is close to that of the first cooling medium, so it is input into the first stage to cool the compressed air together with the first cooling medium to make full use of the cold energy; through multi-stage cooling, the clean compressed air can be liquefied more efficiently, thereby improving the liquefaction rate of the compressed air and the utilization rate of the cold energy.After liquefaction is completed, the liquid air is stored in the energy storage unit to be used for power generation during peak power supply hours to fill the peak power demand, enable the power grid to generate electricity stably, and improve power utilization and system stability; in the energy release stage, the liquid air stored in the energy storage unit is pressurized by the power generation unit to increase the pressure of the liquid air, and then the high-pressure liquid air is vaporized through multi-stage heating to obtain gaseous pressurized air. The cooling medium used in the multi-stage heating process is the cooling medium released in the multi-stage cooling process in the energy storage unit and the cooling medium released after cooling the compressed air before filtration in the compression filtration heat storage unit. The cooling medium that is released is used to recover precious cold energy and regenerate the cooling medium in the multi-stage heating process, thereby achieving The cooling medium and cold energy are recycled; the compressed heat energy stored in the compressed and filtered heat storage unit is used to heat the gaseous pressurized air, so that the temperature of the gaseous pressurized air is further increased, and high-temperature and high-pressure air is obtained, which in turn increases the temperature at the expander inlet and improves the expansion efficiency. At the same time, the heat-released heat storage medium is recovered to achieve the recycling of the heat storage medium; finally, high-temperature and high-pressure air is used to generate electricity, and the generated electricity is used to fill the peak electricity demand, thereby improving the electricity utilization rate and system stability; in this system, a control module can also be set to control the operation of each device in the system during the energy storage stage and the energy release stage, such as starting / closing each device, controlling each valve, and adjusting the flow, pressure and temperature.

[0075] In one example, the compression filtration thermal storage unit includes:

[0076] A plurality of compression heat exchange modules, wherein the plurality of compression heat exchange modules are connected in sequence, each compression heat exchange module is used to compress air or compressed air output by a previous compression heat exchange module, and to perform heat exchange between the compressed air generated by each compression heat exchange module itself and the heat storage medium;

[0077] The cooling and filtering module is arranged between the plurality of compression and heat exchange modules. The cooling and filtering module is used to store the first cooling medium, and to perform heat exchange between the compressed air outputted by the compression and heat exchange module connected to the front stage of the cooling and filtering module and the first cooling medium, to obtain the first cooling medium for release and to store it; to filter the compressed air that has completed the heat exchange; and to transport the filtered compressed air to the compression and heat exchange module connected to the rear stage of the cooling and filtering module for compression and heat exchange again;

[0078] A compression final stage water cooling module, the input end of which is connected to the output end of the last compression heat exchange module, and is used to cool the clean compressed air output by the last compression heat exchange module by cooling water;

[0079] The heat storage medium storage module is used to store the heat storage medium and the heat absorbing heat storage medium, and stores the compression heat energy by storing the heat absorbing heat storage medium.

[0080] Specifically, the compression filtration heat storage unit includes a plurality of compression heat exchange modules, a cooling filtration module, a compression final stage water cooling module and a heat storage medium storage module; the plurality of compression heat exchange modules are connected in sequence, the cooling filtration module is placed between two compression heat exchange modules, the installation position of the cooling filtration module is selected according to the pressure of the inlet compressed air required by the filtering equipment, the number of compression heat exchange modules is selected according to the process requirements and the performance of the compression heat exchange module, the air is compressed step by step through the plurality of compression heat exchange modules until the pressure of the compressed air meets the process requirements, and then the clean compressed air output by the last compression heat exchange module is cooled through the compression final stage water cooling module, each compression module exchanges heat with the high-temperature compressed air obtained by its compression through the heat storage medium to reduce the temperature of the compressed air, and at the same time recovers the compression heat energy through the heat storage medium, and finally The clean compressed air output by the last compression and heat exchange module is cooled by the compression final water cooling module, and the temperature of the clean compressed air is further reduced so that it can be more easily liquefied in the energy storage unit, and the heat energy generated in the compression process is recovered at the same time for use in the energy release stage; during the compression process, the compressed air output by the previous compression and heat exchange module is cooled by the first cooling medium of the cooling and filtering module, and then the compressed air that has been cooled is filtered by the filtering equipment to filter out excess water vapor, oil droplets, solid impurities, etc. in the compressed air to prevent pollution and damage to the power generation equipment. For example, a molecular sieve device is used for filtration, and after obtaining clean compressed air, compression is continued. The heated heat storage medium is stored in the heat storage medium storage module to store the heat energy generated in the compression process of the compression module and used in the energy release stage, thereby realizing the reuse of compressed heat energy.

[0081] In one example, the energy storage unit includes:

[0082] The pre-cooling refrigeration module is used to perform heat exchange between the clean compressed air output by the compression filtration heat storage unit and the second cooling medium and the third cooling medium output by the liquefied cooling module, and store the released second cooling medium; perform expansion refrigeration on a part of the clean compressed air that has completed the heat exchange to obtain expanded air;

[0083] The liquefaction cooling module is used to perform heat exchange between another part of the clean compressed air that has completed heat exchange and the fourth cooling medium and the third cooling medium to obtain liquid air, and store the fourth cooling medium that has released cold; and to expand, decompress and cool the liquid air output by the liquefaction module;

[0084] The liquid air storage module is used to store the liquid air that has completed expansion, decompression and cooling; the expanded air and the evaporated gas generated by the liquid air that has completed expansion, decompression and cooling form a third cooling medium and are sequentially transported to the liquefaction cooling module and the pre-cooling refrigeration module to respectively perform heat exchange with another part of the clean compressed air that has completed heat exchange and the clean compressed air output by the compression, filtration and heat storage unit;

[0085] The input end of the liquefied cooling module is connected to the output end of the pre-cooling refrigeration module, the input end of the liquid air storage module is connected to the output end of the liquefied cooling module, the low-temperature and pressure-reduced air input end of the liquid air storage module is connected to the low-temperature and pressure-reduced air output end of the pre-cooling refrigeration module, the third cooling medium output end of the liquid air storage module is connected to the third cooling medium input end of the liquefied cooling module, and the third cooling medium output end of the liquefied cooling module is connected to the third cooling medium input end of the pre-cooling refrigeration module.

[0086] Specifically, the energy storage unit includes a precooling refrigeration module, a liquefaction cooling module and a liquid air storage module. Liquid air is obtained through two-stage cooling of the precooling refrigeration module and the liquefaction cooling module and stored in the liquid air storage module, that is, the clean compressed air output by the compression and filtration heat storage unit is heat exchanged with the second cooling medium and the third cooling medium output by the liquefaction cooling module through the precooling refrigeration module to further cool the compressed air to complete the precooling of the compressed air, and a part of the precooled clean compressed air is expanded and cooled to reduce the temperature and pressure of the net compressed air to obtain low-temperature expanded air, and then the expanded air is transported to the liquid air storage module for replenishing the third cooling medium in the cooling process; another part of the precooled clean compressed air is heat exchanged with the low-temperature fourth cooling medium and the low-temperature third cooling medium through the liquefaction cooling module, so that the clean compressed air is liquefied, decompressed and expanded, and then transported to the liquid air storage module for storage. The lower the pressure of the liquid air, The higher the storage safety, but if the liquid air storage module cannot withstand a large pressure, for example, the liquid air storage module is a normal pressure tank, then a liquid-air separator tank should be added at the inlet of the normal pressure tank, and the low-temperature and depressurized air generated by the pre-cooling refrigeration module and the liquid air generated by the liquefaction cooling module first enter the liquid-air separator tank, and the flash air formed by the low-temperature and depressurized air and the liquid air is combined into a third cooling medium, which is transported from the air output end of the liquid-air separator tank to the liquefaction cooling module, and then transported to the pre-cooling refrigeration module after the heat exchange is completed. The liquid air is transported from the liquid output end of the liquid-air separator tank to the normal pressure tank for storage; the third cooling medium enters the pre-cooling refrigeration module for heat exchange after completing the heat exchange from the liquid air storage module, thereby further recycling the coldness of the flash air and further improving the energy utilization efficiency of the system. The third cooling medium that has completed the heat exchange is transported to the inlet of the first compression heat exchange module for compression. Because the third cooling medium has been filtered, the consumption of filtering materials can be effectively reduced.

[0087] In one example, a power generation unit includes:

[0088] A pressurizing module, used for pressurizing the liquid air stored in the liquid air storage module and then transporting it to the first cold energy recovery module;

[0089] a first cold energy recovery module, used for performing heat exchange between the fourth cooling medium that has released cold and the pressurized liquid air, heating the liquid air to obtain gaseous pressurized air, and recovering cold energy in the liquid air through the fourth cooling medium that has released cold;

[0090] A second cold energy recovery module is used to perform heat exchange between the second cooling medium that releases cold and the gaseous pressurized air, heat the gaseous pressurized air, and recover cold energy in the gaseous pressurized air through the second cooling medium that releases cold;

[0091] A third cold energy recovery module is used to perform heat exchange again between the first cooling medium that has released cold and the gaseous pressurized air that has completed heat exchange, to heat the gaseous pressurized air again, and to recover cold energy in the gaseous pressurized air again through the first cooling medium that has released cold;

[0092] A plurality of expansion power generation modules, each expansion power generation module includes an air expansion preheating module and a power generation module, the output end of the air expansion preheating module is connected to the input end of the power generation module, and all the expansion power generation modules are connected in sequence;

[0093] The air expansion preheating module is used to perform heat exchange between the heat absorbing thermal storage medium and the gaseous pressurized air that has completed multi-stage heating;

[0094] The power generation module is used to generate electricity by using the gaseous pressurized air that has completed heat exchange in the air expansion preheating module;

[0095] The input end of the pressurizing module is connected to the output end of the liquid air storage module, the output end of the pressurizing module is connected to the input end of the first cold energy recovery module, the output end of the first cold energy recovery module is connected to the input end of the second cold energy recovery module, the output end of the second cold energy recovery module is connected to the input end of the third cold energy recovery module, and the output end of the third cold energy recovery module is connected to the input end of the first air expansion preheating module.

[0096] Specifically, the power generation unit includes a pressurizing module, a first cold energy recovery module, a second cold energy recovery module, a third cold energy recovery module and a plurality of expansion power generation modules. In the energy release stage, the liquid air stored in the liquid air storage module is pressurized by the pressurizing module and then sequentially input into the first cold energy recovery module, the second cold energy recovery module and the third cold energy recovery module for three-stage heating to obtain heated gaseous pressurized air. At the same time, the cold energy in the liquid air is recovered and the first cooling medium, the second cooling medium and the fourth cooling medium are regenerated for the energy storage stage, so that the first cooling medium, the second cooling medium, the fourth cooling medium and the cold energy are recycled. In the energy release stage, the liquid air stored in the liquid air storage module is pressurized by the pressurizing module and then transported to the first cooling medium, the second cooling medium and the third cooling medium for the energy storage stage. a cold energy recovery module, and then through the first cold energy recovery module, the liquid air is heat exchanged with the fourth cooling medium that is heated after releasing the cold, the liquid pressurized air is vaporized to obtain gaseous pressurized air, and the cold energy in the liquid pressurized air is recovered, and then through the second cold energy recovery module, the gaseous pressurized air is heat exchanged with the second cooling medium that is heated after releasing the cold, the cold energy in the gaseous pressurized air is recovered, and the temperature of the gaseous pressurized air is increased, and then through the third cold energy recovery module, the first cooling medium that is heated after releasing the cold is heat exchanged with the heated gaseous pressurized air output by the second cold energy recovery module, the residual cold energy in the gaseous pressurized air is further recovered, the necessary cold energy is provided to the cooling filter module, and the temperature of the gaseous pressurized air is continued to be increased; and then The heated gaseous pressurized air is heat-exchanged with the heat storage medium stored in the thermal storage medium storage module and heated after absorbing heat through the air expansion preheating module of the first expansion power generation module, that is, the compressed gaseous air is heated by utilizing the compression heat stored in the energy storage stage to obtain high-temperature and high-pressure gaseous air, and then the high-temperature gaseous pressurized air is input into the power generation module of the first expansion power generation module to generate electricity, and the gaseous pressurized air that has been cooled and depressurized after power generation enters the air expansion preheating module of the second expansion power generation module to exchange heat with the heat storage medium stored in the thermal storage medium storage module and heated after absorbing heat to obtain high-temperature gaseous pressurized air again, and then the high-temperature gaseous pressurized air is input into the power generation module of the second expansion power generation module to generate electricity. And so on, until the last expansion power generation module completes power generation, the air passing through the last expansion power generation module may still contain a certain amount of heat energy that can be recycled. At this time, an air expansion preheating module can be added before the air expansion preheating module of the first expansion power generation module. Through this air expansion preheating module, the air containing a certain amount of heat energy discharged from the last expansion power generation module is first heat exchanged with the gaseous pressurized air output by the third cold energy recovery module to increase its temperature to reduce the consumption of compression heat energy, and further recover the remaining heat of the air discharged from the last expansion power generation module, so as to achieve the purpose of improving the overall energy utilization efficiency of the system. After the waste heat is recovered, the air discharged from the last expansion power generation module can be directly discharged into the atmosphere.

[0097] In one example, the compression heat exchange module includes:

[0098] Compression module, used to compress air or re-compress filtered clean compressed air;

[0099] A compression heat recovery module is used to perform heat exchange between the heat storage medium and the compressed air or clean compressed air output by the compression module, and to recover compression heat through the heat storage medium;

[0100] The output end of the compression module is connected to the input end of the compression heat energy recovery module.

[0101] Specifically, each compression heat exchange module includes a compression module and a compression heat recovery module. The output end of the compression module is connected to the input end of the compression heat recovery module. The low-pressure air is compressed by the first compression module to obtain high-temperature and high-pressure compressed air, which is then transported to the first compression heat recovery module for heat exchange with the heat storage medium to reduce the temperature of the compressed air and recover the compression heat at the same time. The air is then transported to the second compression module for compression, and then heat exchange is carried out with the heat storage medium through the second compression heat recovery module. After the heat exchange is completed, the air is transported to the third compression module for compression, and so on. According to the requirements of the inlet pressure of the filter equipment, the cooling filter module is installed in a suitable position so that the pressure of the compressed air output by the previous compression heat exchange module meets the requirements of the inlet pressure of the filter equipment; until the compression is completed through all the compression modules, the compressed air is transported to the compression end water cooling module for cooling to reduce the temperature of the clean compressed air so that liquefaction can be completed more efficiently; the number of compression heat exchange modules is selected according to the process requirements.

[0102] In one example, the cooling filter module includes:

[0103] The pre-filter cooling module is used to perform heat exchange between the compressed air output by the compression heat exchange module connected to the front stage of the pre-filter cooling module and the first cooling medium; the input end of the pre-filter cooling module is connected to the output end of the compression heat exchange module connected to the front stage;

[0104] The filter module is used to filter the compressed air output by the pre-filter cooling module to obtain clean compressed air, and transport the clean compressed air to the compression heat exchange module connected to the rear stage of the filter module for compression; the input end of the filter module is connected to the output end of the pre-filter cooling module, and the output end of the filter module is connected to the input end of the compression heat exchange module connected to the rear stage;

[0105] A cold first cooling medium storage module, used for storing a first cooling medium;

[0106] A hot first cooling medium storage module, used for storing a first cooling medium for cooling;

[0107] The cooling medium input end of the pre-filtration cooling module is connected to the output end of the cold first cooling medium storage module, the cooling medium output end of the pre-filtration cooling module is connected to the input end of the hot first cooling medium storage module, the cooling medium output end of the third cold energy recovery module is connected to the input end of the cold first cooling medium storage module, and the cooling medium input end of the third cold energy recovery module is connected to the output end of the hot first cooling medium storage module.

[0108] Specifically, the cooling and filtering module includes a pre-filter cooling module, a filtering module, a cold first cooling medium storage module and a hot first cooling medium storage module; the input end of the pre-filter cooling module is connected to the output end of the compression heat exchange module in front of it, that is, it is connected to the output end of the compression heat recovery module of the previous compression heat exchange module, the input end of the filtering module is connected to the output end of the pre-filter cooling module, and the output end of the filtering module is connected to the input end of the compression heat exchange module behind it, that is, the compressed air output by the previous compression heat recovery module enters the filtering module for filtration after completing heat exchange in the pre-filter cooling module, and the clean compressed air obtained after filtration enters the compression module of the subsequent compression heat exchange module for compression; the cooling medium input end of the pre-filter cooling module is connected to the output end of the cold first cooling medium storage module, and the cooling medium output end of the pre-filter cooling module is connected to the hot first cooling The input end of the medium storage module is connected, the cooling medium output end of the third cold energy recovery module is connected to the input end of the cold first cooling medium storage module, and the cooling medium input end of the third cold energy recovery module is connected to the output end of the hot first cooling medium storage module. In the energy storage stage, the first cooling medium stored in the cold first cooling medium storage module is transported to the pre-filtration cooling module to exchange heat with the compressed air output by the previous compression heat energy recovery module to cool the compressed air, and the heated first cooling medium that completes the heat exchange is transported to the hot first cooling medium storage module for storage. In the energy release stage, the heated first cooling medium stored in the hot first cooling medium storage module is transported to the third cold energy recovery module to exchange heat with the gaseous pressurized air output by the second cold energy recovery module, and the cooled first cooling medium that completes the heat exchange is transported to the cold first cooling medium storage module for storage, waiting for use in the energy storage stage.

[0109] In one example, a thermal storage medium storage module includes:

[0110] A cold thermal storage medium storage module, used for storing thermal storage medium;

[0111] A thermal storage medium storage module for storing heat absorbing thermal storage medium;

[0112] The heat storage medium input end of the compression heat recovery module is connected to the output end of the cold heat storage medium storage module, the heat storage medium output end of the compression heat recovery module is connected to the input end of the hot heat storage medium storage module, the input end of the cold heat storage medium storage module is connected to the heat storage medium output end of the air expansion preheating module, and the output end of the hot heat storage medium storage module is connected to the heat storage medium input end of the air expansion preheating module.

[0113] Specifically, the heat storage medium storage module includes a cold heat storage medium storage module and a hot heat storage medium storage module. The heat storage medium input end of the compression heat recovery module is connected to the output end of the cold heat storage medium storage module, the heat storage medium output end of the compression heat recovery module is connected to the input end of the hot heat storage medium storage module, the input end of the cold heat storage medium storage module is connected to the heat storage medium output end of the air expansion preheating module, and the output end of the hot heat storage medium storage module is connected to the heat storage medium input end of the air expansion preheating module. In the energy storage stage, the heat storage medium stored in the cold heat storage medium storage module is transported to all the compression heat recovery modules corresponding to the compression heat recovery modules. The generated compressed air is heat exchanged, and the compression heat energy in the compressed air is stored by the heat storage medium. The heated heat storage medium obtained after the heat exchange is transported to the hot heat storage medium storage module for storage. In the energy release stage, the heated heat storage medium stored in the hot heat storage medium storage module is transported to the air expansion preheater of all expansion power generation modules to exchange heat with the gaseous pressurized air transported by the third cold energy recovery module or the gaseous pressurized air output by the power generation module of the upper-level expansion power generation module of the air expansion preheating module, so as to effectively utilize the compression heat energy generated by the compression module, and transport the low-temperature heat storage medium that has completed the heat exchange to the cold heat storage medium storage module for storage, waiting for use in the energy storage stage.

[0114] In one example, the pre-cooling refrigeration module includes:

[0115] The air precooling module is used to perform heat exchange between the second cooling medium, the third cooling medium output by the liquefied cooling module and the clean compressed air output by the final compression water cooling module;

[0116] A cold second cooling medium storage module, used for storing a second cooling medium;

[0117] A hot second cooling medium storage module, used for storing a second cooling medium for cooling;

[0118] An air refrigeration expansion module is used to expand and refrigerate a portion of the clean compressed air output by the air precooling module to obtain expanded air;

[0119] The input end of the air precooling module is connected to the output end of the compression final stage water cooling module, the second cooling medium input end of the air precooler is connected to the output end of the cold second cooling medium storage module, the second cooling medium output end of the air precooling module is connected to the input end of the hot second cooling medium storage module, the input end of the cold second cooling medium storage module is connected to the cooling medium output end of the second cold energy recovery module, the output end of the hot second cooling medium storage module is connected to the cooling medium input end of the second cold energy recovery module, the input end of the air refrigeration expansion module is connected to the second output end of the air precooling module, and the output end of the air refrigeration expansion module is connected to the low-temperature decompression air input end of the liquid air storage module.

[0120] Specifically, the precooling refrigeration module includes an air precooling module, a cold second cooling medium storage module and a hot second cooling medium storage module. The input end of the air precooling module is connected to the output end of the compression final water cooling module, the cooling medium input end of the air precooling module is connected to the output end of the cold second cooling medium storage module, the cooling medium output end of the air precooling module is connected to the input end of the hot second cooling medium storage module, the input end of the cold second cooling medium storage module is connected to the cooling medium output end of the second cold energy recovery module, the output end of the hot second cooling medium storage module is connected to the cooling medium input end of the second cold energy recovery module, the input end of the air refrigeration expansion module is connected to the first output end of the air precooling module, and the output end of the air refrigeration expansion module is connected to the low-temperature decompression air input end of the liquid air storage module. In the energy storage stage, the second cooling medium stored in the cold second cooling medium storage module is input into the air precooling module for heat exchange with the clean compressed air output from the compression final water cooling module to reduce the temperature of the clean compressed air. The heated second cooling medium obtained after the heat exchange is input into the hot second cooling medium storage module for storage. A part of the pre-cooled clean compressed air output by the cooling module is input into the air refrigeration expansion module for expansion refrigeration. After the expanded air is obtained, it is input into the liquid air storage module and the flash air generated by the liquefaction module and the evaporated gas of the liquid air in the liquid air storage module to form a third cooling medium, which is transported to the liquefaction cooling module and the other part of the pre-cooled clean compressed air output by the air pre-cooling module for heat exchange, and then transported to the air pre-cooling module to cool the clean compressed air output by the compression final water cooling module together with the second cooling medium, and the third cooling medium which has completed the heat exchange again The hot second cooling medium is transported to the inlet of the first compression heat exchange module to provide clean air to reduce filtering consumables; in the energy release stage, the heated second cooling medium stored in the hot second cooling medium storage module is transported to the second cold energy recovery module for heat exchange with the gaseous pressurized air output by the first cold energy recovery module to increase the temperature of the gaseous pressurized air. The cooled second cooling medium obtained after the heat exchange is input into the cold second cooling medium storage module for storage, and the cold energy in the second cooling medium and the gaseous pressurized air is recovered for use in the energy storage stage, thereby realizing the recycling of cold energy and the second cooling medium.

[0121] In one example, the liquefaction module includes:

[0122] An air liquefaction module, used for performing heat exchange between the fourth cooling medium, the third cooling medium outputted by the liquid air storage module and the clean compressed air outputted by the first output end of the air precooling module to obtain liquid air;

[0123] A cold fourth cooling medium storage module, used for storing a fourth cooling medium;

[0124] A hot fourth cooling medium storage module, used for storing a fourth cooling medium for cooling;

[0125] A liquid air expansion module, used for expanding, decompressing and cooling the liquid air output by the air liquefaction module;

[0126] The input end of the air liquefaction module is connected to the first output end of the air precooling module, the cooling medium input end of the air liquefaction module is connected to the output end of the cold fourth cooling medium storage module, the cooling medium output end of the air liquefaction module is connected to the input end of the hot fourth cooling medium storage module, the input end of the cold fourth cooling medium storage module is connected to the cooling medium output end of the first cold energy recovery module, and the output end of the hot fourth cooling medium storage module is connected to the cooling medium input end of the first cold energy recovery module; the input end of the liquid air expansion module is connected to the output end of the air liquefaction module, and the output end of the liquid air expansion module is connected to the liquid air storage module.

[0127] Specifically, the liquefaction cooling module includes an air liquefaction module, a cold fourth cooling medium storage module, a hot fourth cooling medium storage module and an air refrigeration expansion module, the input end of the air liquefaction module is connected to the second output end of the air precooling module, the output end of the air liquefaction module is connected to the input end of the liquid air expansion module, the cooling medium input end of the air liquefaction module is connected to the output end of the cold fourth cooling medium storage module, the cooling medium output end of the air liquefaction module is connected to the input end of the hot fourth cooling medium storage module, the input end of the cold fourth cooling medium storage module is connected to the cooling medium output end of the first cooling recovery module, and the output end of the hot fourth cooling medium storage module is connected to the cooling medium input end of the first cooling recovery module; in the energy storage stage, the fourth cooling medium stored in the cold fourth cooling medium storage module is input into the air liquefaction module and the clean compressed air output by the air precooling module for heat exchange, so that the clean compressed air is liquefied, and the liquid air is obtained and then input into the liquid air storage module for storage, and the heated fourth cooling medium obtained after the heat exchange is input into the hot fourth cooling medium storage module. The fourth cooling medium is stored in the storage module of the cooling medium. When there is liquid air in the liquid air storage module, the evaporated gas generated by the liquid air, the flash air generated after passing through the liquid air expansion module and the expanded air generated by the air refrigeration expansion module form the third cooling medium in the liquid air storage module, and then the third cooling medium that has completed the heat exchange is transported to the air precooling module to cool the clean compressed air output by the air precooling module together with the second cooling medium. In the energy release stage, the heated fourth cooling medium is input into the first cold energy recovery module to exchange heat with the pressurized liquid air output by the liquid air storage module, so that the liquid pressurized air is vaporized to obtain gaseous pressurized air. At the same time, the fourth cooling medium obtained after the heat exchange is transported to the cold fourth cooling medium module for storage, and the fourth cooling medium is recovered and the cold energy in the liquid air is recovered by the cold fourth cooling medium for use in the energy storage stage, thereby realizing the recycling of cold energy and the fourth cooling medium.

[0128] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but is not intended to be limiting of the present invention. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0129] Example 1

[0130] like Figure 2 As shown, a liquid air energy storage power generation system according to the present invention includes:

[0131] Two compressors 1 and two compression heat recovery devices 2, the output end of each compressor 1 is connected to the input end of the corresponding compression heat recovery device 2; a compression end water cooler 3, whose input end is connected to the output end of the second compression heat recovery device 2; a molecular sieve pre-cooler 4, whose input end is connected to the output end of the first compression heat recovery device 2; a molecular sieve 5, whose input end is connected to the output end of the molecular sieve pre-cooler 4, and whose output end is connected to the input end of the second compressor 1; a hot molecular sieve cooling medium storage tank 6, whose input end is connected to the cooling medium output end of the molecular sieve pre-cooler 4; a cold molecular sieve cooling medium storage tank 7, whose output end is connected to the cooling medium input end of the molecular sieve pre-cooler 4 The molecular sieve heat exchanger 8 has a cooling medium input end connected to the output end of the hot molecular sieve cooling medium storage tank 6, and its cooling medium output end is connected to the input end of the cold molecular sieve cooling medium storage tank 7; the air precooler 9 has an input end connected to the output end of the compression end water cooler 3; the air refrigeration expander 10 has an input end connected to the first output end of the air precooler 9; the air liquefier 11 has an input end connected to the second output end of the air precooler 9, and its flash air output end is connected to the flash air input end of the air precooler 9; the liquid air expansion valve 12 has an input end connected to the output end of the air liquefier 11; the liquid air storage tank 14 has a first input end connected to the air system The output end of the cold expander 10 is connected, and its second input end is connected to the output end of the liquid air expansion valve 12, and its flash air output end is connected to the flash air input end of the air liquefier 11; the hot shallow cold medium storage tank 15, whose input end is connected to the shallow cold medium output end of the air precooler 9; the cold shallow cold medium storage tank 16, whose output end is connected to the shallow cold medium input end of the air precooler 9; the hot deep cold medium storage tank 17, whose input end is connected to the deep cold medium output end of the air liquefier 11; the cold deep cold medium storage tank 18, whose output end is connected to the deep cold medium input end of the air liquefier 11; the hot heat storage medium storage module 19, whose input end is connected to the heat storage of all compression heat recovery devices 2. The medium output end is connected; the cold heat storage medium storage module 20, whose output end is connected to the heat storage medium input end of all the compression heat recovery devices 2; the booster pump 25, whose input end is connected to the output end of the liquid air storage tank 14, the cryogenic recovery device 21, whose input end is connected to the output end of the booster pump 25, whose cryogenic medium input end is connected to the output end of the hot cryogenic medium storage tank 17, and whose cryogenic medium output end is connected to the input end of the cold cryogenic medium storage tank 18; the shallow cold recovery device 22, whose input end is connected to the output end of the cryogenic recovery device 21, whose shallow cold medium input end is connected to the output end of the hot shallow cold medium storage tank 15, and whose shallow cold medium output end is connected to the input end of the cold shallow cold medium storage tank 16;The molecular sieve post-heat exchanger 8 has an input end connected to the output end of the shallow cold recovery device 22, a cooling medium input end connected to the output end of the hot molecular sieve cooling medium storage tank 6, and a cooling medium output end connected to the cold molecular sieve cooling medium storage tank 7; two air expansion preheaters 23 and two turbine generator sets 24, the output end of each air expansion preheater 23 is connected to the input end of a corresponding turbine generator set 24, the output end of the first turbine generator set 24 is connected to the input end of the second air expansion preheater 23, the heat storage medium input end of each air expansion preheater 23 is connected to the output end of the hot heat storage medium storage module 19, the heat storage medium output end of each air expansion preheater 23 is connected to the input end of the cold heat storage medium storage module 20, the input end of the first air expansion preheater 23 is connected to the output end of the molecular sieve post-heat exchanger 8, and the second turbine generator set 24 is connected to the input end of the second air expansion preheater 23. The output end of the unit 24 is introduced into the atmosphere, or a third air expansion preheater 23 is added between the first air expansion preheater 23 and the molecular sieve post-heat exchanger 8, the output end of the second turbine generator unit 24 is connected to the heat storage medium input end of the third air expansion preheater 23, the heat storage medium output end of the third air expansion preheater 23 is connected to the atmosphere, the residual heat energy of the air output by the second turbine generator unit 24 is used to heat the gaseous and liquid air input to the third air expansion preheater 23, and the residual heat in the air discharged by the second turbine generator unit 24 is further recovered, so as to achieve the purpose of improving the overall energy utilization efficiency of the system. After the waste heat is recovered, the air discharged from the last expansion power generation module can be directly discharged into the atmosphere; the heat storage medium, the deep cold medium, the shallow cold medium and the molecular sieve cooling medium are all liquid, and the output ends of their corresponding storage tanks are all provided with pumps for transporting each medium. ;

[0132] In the energy storage stage, i.e., the low electricity consumption stage, the first compressor 1 compresses the outside air into high-temperature and high-pressure compressed air, and exchanges heat between the high-temperature and high-pressure compressed air and the low-temperature heat storage medium output by the cold heat storage medium storage module 20 through the second compression heat recovery device 2, thereby reducing the temperature of the compressed air, storing the compression heat energy generated by the first compressor 1 in the heat storage medium, obtaining the heated heat storage medium, and storing it in the hot heat storage medium storage module 19, thereby storing the compression heat energy generated by the first compressor 1; the cooled compressed air is input into the molecular sieve pre-cooler 4 and output to the cold molecular sieve cooling medium storage tank 7 The low-temperature molecular sieve cooling medium is heat exchanged to further reduce the temperature of the compressed air, and the heated molecular sieve cooling medium is obtained and stored in the hot molecular sieve cooling medium storage tank 6; the compressed air that has been cooled again is input into the molecular sieve 5 for filtration to obtain clean compressed air, and then the clean compressed air is input into the second compressor 1 for recompression, and the compressed clean compressed air is heat exchanged with the low-temperature heat storage medium output by the cold heat storage medium storage module 20 in the second heat recovery device 2 to reduce the temperature of the compressed air, and the compression heat energy generated by the second compressor 1 is stored in the heat storage medium to obtain The heated heat storage medium is stored in the hot heat storage medium storage module 19, and the compression heat energy generated by the second compressor 1 is stored; the clean compressed air output by the second heat recovery device 2 is input to the compression end water cooler 3 for cooling, and after the temperature of the clean compressed air is reduced, it is input to the air precooler 9 for heat exchange with the low-temperature shallow cold medium output by the cold shallow cold medium storage tank 16, and the temperature of the compressed air is further reduced to obtain the heated shallow cold medium and the cooled clean compressed air; when the air liquefier 11 is able to output low-temperature flash air to the air precooler 9, the low-temperature flash air is exchanged with the low-temperature shallow cold medium. The clean compressed air outputted from the compression end water cooler 3 is cooled and de-temperatured together with the warm shallow cold medium to obtain the warmed shallow cold medium, the cooled clean compressed air and the warmed flash air. The warmed shallow cold medium is inputted into the hot shallow cold medium storage tank 15 for storage, and the warmed flash air is inputted into the first compressor 1 for compression or directly discharged into the atmosphere; the compressed air is inputted into the air refrigeration expander 10 through the first output end of the air precooler 9 for expansion and refrigeration, and the expanded low-temperature depressurized air enters the liquid air storage tank 14 and combines with the flash air generated by the liquid air expansion valve to form low-temperature flash air;The clean compressed air is input into the air liquefier 11 through the second output end of the air precooler 9 to exchange heat with the low-temperature cryogenic medium output from the cold cryogenic medium storage tank 18 to obtain liquid air and heated cryogenic medium. When the liquid air storage tank 14 can output low-temperature flash air to the air liquefier 11, the clean compressed air output from the air precooler 9 is cooled by the low-temperature flash air and the low-temperature cryogenic medium to obtain liquid air, heated cryogenic medium and heated flash air. The heated flash air is input into the air precooler 9 for heat exchange, and the heated cryogenic medium is input into the hot cryogenic medium storage tank 17 for storage; the liquid air is input into the liquid air expansion valve 12 for decompression, and then the decompressed liquid air is input into the liquid air storage tank 14 for storage. When the liquid air is decompressed, the temperature is also reduced due to the generation of flash air. The generated flash air is input into the liquid air storage tank 14 to supplement the cooling capacity of the flash air together with the low-temperature decompressed air output from the air refrigeration expander 10 to the liquid air storage tank 14;

[0133] like Figure 3 As shown, a liquid air separator tank 13 can be added between the liquid air expansion valve 12 and the liquid air storage tank 14 according to actual conditions, wherein the output end thereof is connected to the input end of the liquid air storage tank 14, the first input end thereof is connected to the output end of the air refrigeration expander 10, and the second input end thereof is connected to the output end of the liquid air expansion valve 12, and the liquid air output by the liquid air expansion valve 12, the flash air and the low-temperature decompression air output by the air refrigeration expander 10 are subjected to liquid-gas separation, and then the low-temperature decompression air and the flash air are merged into the low-temperature evaporated gas of the liquid air storage tank 14 through the first output end of the liquid air separator tank 13 to form a low-temperature flash air, and the low-temperature flash air is sent back to the air liquefier 11 as a cold source supplement, and the liquid air is input into the liquid air storage tank 14 through the second output end of the liquid air separator tank 13 for storage.

[0134] In the energy release stage, i.e., the peak power consumption stage, the liquid air stored in the liquid air storage tank 14 is transported to the cryogenic recovery device 21 by the booster pump 25 to exchange heat with the heated cryogenic medium output from the hot cryogenic medium storage tank 17 to gasify it, and the low-temperature cryogenic medium after heat exchange is transported to the cold cryogenic medium storage tank 18 for storage, thereby recovering the cold energy in the liquid air and regenerating the low-temperature cryogenic medium; the gaseous pressurized air output from the cryogenic recovery device 21 is input to the shallow cooling recovery device 22 to exchange heat with the heated shallow cooling medium output from the hot shallow cooling medium storage tank 15 to increase the temperature of the gaseous pressurized air, and the low-temperature shallow cooling medium after heat exchange is transported to the cold shallow cooling medium storage tank 16 for storage, and the gaseous pressurized air is recovered. The cold energy in the gaseous pressurized air is recovered and the low-temperature shallow cold medium is regenerated; the gaseous pressurized air output by the shallow cold recovery device 22 is input into the molecular sieve post-heat exchanger 8 to exchange heat with the heated molecular sieve cooling medium output by the hot molecular sieve cooling medium storage tank 6, so as to further increase the temperature of the gaseous pressurized air, and the low-temperature molecular sieve cooling medium after heat exchange is transported to the cold molecular sieve cooling medium storage tank 7 for storage, so as to recover the cold energy in the gaseous pressurized air and regenerate the low-temperature molecular sieve cooling medium. At this time, the cold energy in the liquid air has been recycled three times, and the energy recovery is basically maximized; the gaseous pressurized air output by the molecular sieve post-heat exchanger 8 is input into the first air expansion preheater 23 to exchange heat with ... to store, so as to recover the cold energy in the gaseous pressurized air and regenerate the low-temperature molecular sieve cooling medium. The heated heat storage medium output by the heat storage medium storage module 19 is heat exchanged, and the compressed gaseous pressurized air is heated again by using the compressed heat energy stored in the energy storage stage, so as to increase the inlet temperature of the first turbine generator set 24 and thus improve the expansion efficiency, so as to ensure the working efficiency of the first turbine generator set 24, and the high-temperature gaseous pressurized air output by the first air expansion preheater 23 is input into the first turbine generator set 24 for power generation, and the sub-high-pressure air that has been cooled after power generation is input into the second air expansion preheater 23 for heat exchange with the heated heat storage medium output by the heat storage medium storage module 19 again, and then the high-temperature gaseous pressurized air output by the second air expansion preheater 23 is input into the second ... high-temperature gaseous pressurized air output by the second air expansion preheater 23 is input into the second turbine generator set 24 for power generation, and the high-temperature gaseous pressurized air output by the second turbine generator set 24 is input into the second turbine generator set 24 for power generation, and the high-temperature gaseous pressurized air output by the second turbine generator set 24 is input into the second turbine generator set 24 for power generation, and the high-temperature gaseous pressurized air output by the second turbine generator set 24 is input into the second turbine generator set 24 for power generation, and the high-temperature gaseous pressurized air output by the second turbine generator set 24 is input into the second turbine generator set 24 for power generation, and the high-temperature gaseous pressurized air output by the second turbine The compressed air is input to the second turbine generator set 24 for power generation, which is used to supplement the electricity demand and play a role in stabilizing the power grid and shaving peaks and filling valleys; the heat storage medium, the cryogenic medium and the shallow cooling medium are all liquid, and the expression of the low temperature and the rising temperature of the heat storage medium, the cryogenic medium and the shallow cooling medium is not limited to only two levels of gradient levels of cold storage or heat storage medium. Two or more gradient levels can be flexibly defined according to the temperature change range of the whole process energy storage working fluid and the boiling point of the heat storage medium, the cryogenic medium and the shallow cooling medium; in this system, a control module can also be set to control the operation of each device in the system during the energy storage stage and the energy release stage, such as starting / shutting down each device, adjusting the flow, pressure and temperature, etc.

[0135] Example 2

[0136] like Figure 4As shown, this embodiment provides a liquid air energy storage power generation method, which is applied to the liquid air energy storage power generation system described in Example 1, including:

[0137] In the energy storage stage, compressed air is obtained by compressing air, and the compressed air is heat-exchanged with the heat storage medium to obtain the heat-absorbing heat storage medium;

[0138] The compressed air that has completed the heat exchange is cooled and filtered to obtain clean compressed air, and the clean compressed air is compressed again to exchange heat with the heat storage medium again; the compressed heat energy in the compressed air or clean compressed air is stored by the heat storage medium that absorbs heat; the clean compressed air that has completed the last heat exchange is cooled and transported to the energy storage unit;

[0139] The clean compressed air that has been cooled is liquefied through multi-stage cooling to obtain liquid air and store it;

[0140] In the energy release stage, the liquid air stored in the energy storage unit is pressurized so that the liquid air is input into the power generation unit, and the pressurized liquid air is subjected to multi-stage heating by the cooling medium released during the compression and filtration heat storage unit and the cooling process of the energy storage unit, so as to obtain gaseous pressurized air; the gaseous pressurized air is heated by the compression heat energy stored in the heat storage medium that absorbs heat, and then electricity is generated by the heated gaseous pressurized air, and the cold energy is recovered by the cooling medium in the multi-stage heating process.

[0141] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A liquid air energy storage power generation system, characterized in that: include: A compression filtration heat storage unit, used for compressing air to obtain compressed air, and performing heat exchange between the compressed air and a heat storage medium to obtain the heat storage medium that absorbs heat; The compressed air that has completed the heat exchange is cooled and filtered to obtain clean compressed air, and the clean compressed air is compressed again to perform heat exchange with the heat storage medium again; storing compression heat energy in the compressed air or the clean compressed air by the heat storage medium that absorbs heat; Cooling the clean compressed air that has completed the last heat exchange and then transmitting it to the energy storage unit; An energy storage unit, used for liquefying the clean compressed air that has completed the cooling through multi-stage cooling to obtain liquid air and store it; The power generation unit is used for, in the energy release stage, pressurizing the liquid air stored in the energy storage unit so that the liquid air is input into the power generation unit, and performing multi-stage heating on the pressurized liquid air through the cooling medium released during the cooling process of the compression filtration heat storage unit and the energy storage unit to obtain gaseous pressurized air; heating the gaseous pressurized air by using the compression heat energy stored in the heat storage medium that absorbs heat, and then generating electricity by using the heated gaseous pressurized air, and recovering cold energy during the multi-stage heating process through the cooling medium.

2. The liquid air energy storage power generation system according to claim 1, characterized in that: The compression filtration heat storage unit comprises: A plurality of compression heat exchange modules, wherein the plurality of compression heat exchange modules are connected in sequence, each of the compression heat exchange modules is used to compress the air or the compressed air output by the previous compression heat exchange module, and to perform heat exchange between the compressed air generated by each compression heat exchange module itself and the heat storage medium; A cooling filter module is arranged between the plurality of compression and heat exchange modules, and is used to store a first cooling medium, and to perform heat exchange between the compressed air outputted by the compression and heat exchange module connected to the front stage of the cooling filter module and the first cooling medium, to obtain the first cooling medium that has been released and to store it; to filter the compressed air that has completed the heat exchange; and to transport the compressed air that has completed the filtration to the compression and heat exchange module connected to the rear stage of the cooling filter module for compression and heat exchange again; A compression final stage water cooling module, the input end of the compression final stage water cooling module is connected to the output end of the last compression heat exchange module, and is used to cool the clean compressed air output by the last compression heat exchange module by cooling water; The heat storage medium storage module is used to store the heat storage medium and the heat absorbing heat storage medium, and stores the compression heat energy by storing the heat absorbing heat storage medium.

3. The liquid air energy storage power generation system according to claim 2, characterized in that: The energy storage unit comprises: A pre-cooling refrigeration module is used to perform heat exchange between the clean compressed air output by the compression filtration heat storage unit and the second cooling medium and the third cooling medium output by the liquefied cooling module, and store the released second cooling medium; perform expansion refrigeration on a part of the clean compressed air that has completed the heat exchange to obtain expanded air; A liquefaction cooling module is used to perform heat exchange between another part of the clean compressed air that has completed the heat exchange and the fourth cooling medium and the third cooling medium to obtain the liquid air, and store the fourth cooling medium that has released cold; and to perform expansion, decompression and cooling on the liquid air output by the liquefaction module; A liquid air storage module is used to store the liquid air that has completed the expansion and decompression cooling; the expanded air and the evaporated gas generated by the liquid air that has completed the expansion and decompression cooling form the third cooling medium, which is sequentially transported to the liquefied cooling module and the pre-cooling refrigeration module to respectively perform heat exchange with another part of the clean compressed air that has completed the heat exchange and the clean compressed air output by the compression, filtration and heat storage unit; The input end of the liquefied cooling module is connected to the output end of the pre-cooling refrigeration module, the input end of the liquid air storage module is connected to the output end of the liquefied cooling module, the low-temperature and pressure-reduced air input end of the liquid air storage module is connected to the low-temperature and pressure-reduced air output end of the pre-cooling refrigeration module, the third cooling medium output end of the liquid air storage module is connected to the third cooling medium input end of the liquefied cooling module, and the third cooling medium output end of the liquefied cooling module is connected to the third cooling medium input end of the pre-cooling refrigeration module.

4. The liquid air energy storage power generation system according to claim 3, characterized in that: The power generation unit comprises: A pressurizing module, used for pressurizing the liquid air stored in the liquid air storage module and then transporting the pressurized liquid air to the first cold energy recovery module; a first cold energy recovery module, used for performing heat exchange between the released fourth cooling medium and the pressurized liquid air, heating the liquid air to obtain gaseous pressurized air, and recovering cold energy in the liquid air through the released fourth cooling medium; a second cold energy recovery module, used for performing heat exchange between the second cooling medium that has released cold and the gaseous pressurized air, heating the gaseous pressurized air, and recovering cold energy in the gaseous pressurized air through the second cooling medium that has released cold; a third cold energy recovery module, used for performing heat exchange again between the first cooling medium that has released cold and the gaseous pressurized air that has completed the heat exchange, heating the gaseous pressurized air again, and recovering cold energy in the gaseous pressurized air again through the first cooling medium that has released cold; A plurality of expansion power generation modules, each of which includes an air expansion preheating module and a power generation module, the output end of the air expansion preheating module is connected to the input end of the power generation module, and all the expansion power generation modules are connected in sequence; The air expansion preheating module is used to perform heat exchange between the heat storage medium that absorbs heat and the gaseous pressurized air that has completed the multi-stage heating; The power generation module is used to generate electricity through the gaseous pressurized air that has completed heat exchange in the air expansion preheating module; The input end of the pressurizing module is connected to the output end of the liquid air storage module, the output end of the pressurizing module is connected to the input end of the first cold energy recovery module, the output end of the first cold energy recovery module is connected to the input end of the second cold energy recovery module, the output end of the second cold energy recovery module is connected to the input end of the third cold energy recovery module, and the output end of the third cold energy recovery module is connected to the input end of the first air expansion preheating module.

5. The liquid air energy storage power generation system according to claim 4, characterized in that: The compression heat exchange module comprises: A compression module, used to compress the air or re-compress the filtered clean compressed air; A compression heat recovery module, used for performing heat exchange between the heat storage medium and the compressed air or the clean compressed air output by the compression module, and recovering the compression heat through the heat storage medium; The output end of the compression module is connected to the input end of the compression heat energy recovery module.

6. The liquid air energy storage power generation system according to claim 5, characterized in that: The cooling filter module comprises: A pre-filter cooling module, used for performing heat exchange between the compressed air output by the compression heat exchange module connected to the front stage of the pre-filter cooling module and the first cooling medium; the input end of the pre-filter cooling module is connected to the output end of the compression heat exchange module connected to the front stage; A filter module is used to filter the compressed air output by the pre-filter cooling module to obtain the clean compressed air, and transmit the clean compressed air to the compression heat exchange module connected to the rear stage of the filter module for compression; the input end of the filter module is connected to the output end of the pre-filter cooling module, and the output end of the filter module is connected to the input end of the compression heat exchange module connected to the rear stage; A cold first cooling medium storage module, used for storing the first cooling medium; A hot first cooling medium storage module, used for storing the first cooling medium for cooling; The cooling medium input end of the pre-filtration cooling module is connected to the output end of the cold first cooling medium storage module, the cooling medium output end of the pre-filtration cooling module is connected to the input end of the hot first cooling medium storage module, the cooling medium output end of the third cold energy recovery module is connected to the input end of the cold first cooling medium storage module, and the cooling medium input end of the third cold energy recovery module is connected to the output end of the hot first cooling medium storage module.

7. The liquid air energy storage power generation system according to claim 6, characterized in that: The thermal storage medium storage module comprises: A cold thermal storage medium storage module, used for storing the thermal storage medium; A thermal storage medium storage module for storing the thermal storage medium that absorbs heat; The heat storage medium input end of the compression heat recovery module is connected to the output end of the cold heat storage medium storage module, the heat storage medium output end of the compression heat recovery module is connected to the input end of the hot heat storage medium storage module, the input end of the cold heat storage medium storage module is connected to the heat storage medium output end of the air expansion preheating module, and the output end of the hot heat storage medium storage module is connected to the heat storage medium input end of the air expansion preheating module.

8. The liquid air energy storage power generation system according to claim 7, characterized in that: The pre-cooling refrigeration module comprises: An air precooling module, used for performing heat exchange between the second cooling medium, the third cooling medium output by the liquefied cooling module and the clean compressed air output by the final compression water cooling module; A cold second cooling medium storage module, used for storing the second cooling medium; A hot second cooling medium storage module, used for storing the second cooling medium for cooling; An air refrigeration expansion module, used for expanding and refrigerating a portion of the clean compressed air output by the air precooling module to obtain the expanded air; The input end of the air precooling module is connected to the output end of the compression final stage water cooling module, the second cooling medium input end of the air precooler is connected to the output end of the cold second cooling medium storage module, the second cooling medium output end of the air precooling module is connected to the input end of the hot second cooling medium storage module, the input end of the cold second cooling medium storage module is connected to the cooling medium output end of the second cold energy recovery module, the output end of the hot second cooling medium storage module is connected to the cooling medium input end of the second cold energy recovery module, the input end of the air refrigeration expansion module is connected to the second output end of the air precooling module, and the output end of the air refrigeration expansion module is connected to the low-temperature decompression air input end of the liquid air storage module.

9. The liquid air energy storage power generation system according to claim 8, characterized in that: The liquefaction cooling module comprises: an air liquefaction module, configured to perform heat exchange between the fourth cooling medium, the third cooling medium outputted by the liquid air storage module, and the clean compressed air outputted by the first output end of the air precooling module, so as to obtain the liquid air; A cold fourth cooling medium storage module, used for storing the fourth cooling medium; A hot fourth cooling medium storage module, used for storing the fourth cooling medium for cooling; A liquid air expansion module, used for expanding, depressurizing and cooling the liquid air output by the air liquefaction module; The input end of the air liquefaction module is connected to the first output end of the air precooling module, the cooling medium input end of the air liquefaction module is connected to the output end of the cold fourth cooling medium storage module, the cooling medium output end of the air liquefaction module is connected to the input end of the hot fourth cooling medium storage module, the input end of the cold fourth cooling medium storage module is connected to the cooling medium output end of the first cold energy recovery module, and the output end of the hot fourth cooling medium storage module is connected to the cooling medium input end of the first cold energy recovery module; the input end of the liquid air expansion module is connected to the output end of the air liquefaction module, and the output end of the liquid air expansion module is connected to the liquid air storage module.

10. A liquid air energy storage power generation method, applied to the liquid air energy storage system according to any one of claims 1 to 9, characterized in that: include: In the energy storage stage, compressed air is obtained by compressing air, and the compressed air is heat-exchanged with a heat storage medium to obtain the heat-absorbing heat storage medium; The compressed air that has completed the heat exchange is cooled and filtered to obtain clean compressed air, and the clean compressed air is compressed again to perform heat exchange with the heat storage medium again; storing compression heat energy in the compressed air or the clean compressed air by the heat storage medium that absorbs heat; Cooling the clean compressed air that has completed the last heat exchange and then transmitting it to the energy storage unit; liquefying the clean compressed air that has completed the cooling through multi-stage cooling to obtain liquid air and store it; In the energy release stage, the liquid air stored in the energy storage unit is pressurized so as to be input into the power generation unit, and the pressurized liquid air is subjected to multi-stage heating by the cooling medium released during the cooling process of the compression filtration heat storage unit and the energy storage unit to obtain gaseous pressurized air; the gaseous pressurized air is heated by the compressed heat energy stored in the heat storage medium that absorbs heat, and then electricity is generated by the heated gaseous pressurized air, and cold energy is recovered during the multi-stage heating process by the cooling medium.

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