WO2022166381A1 - Energy storage device and method based on co2 gas-liquid phase change for supplementing external energy - Google Patents

Abstract

An energy storage device based on CO2 gas-liquid phase change for supplementing external energy, comprising: a gas storage pool (100); a liquid storage tank (200); an energy storage assembly (300), the energy storage assembly (300) being provided between the gas storage pool (100) and the liquid storage tank (200); an energy release assembly (400), the energy release assembly (400) being provided between the gas storage pool (100) and the liquid storage tank (200), the energy release assembly (400) comprising at least one expansion and release portion, and the expansion and release portion comprising an energy release heat exchanger, a supplemental energy heat exchanger, and an expander; a heat exchange assembly (500), the energy storage assembly (300) and the energy release assembly (400) being both connected to the heat exchange assembly (500), and the heat exchange assembly (500) transferring part of energy generated in the energy storage assembly (300) into the energy release assembly (400); and an energy supplement assembly, comprising an external heat source (810), the supplemental energy heat exchanger being connected to the external heat source (810), and the external heat source (810) supplying energy to the expander by means of the supplemental energy heat exchanger.

Description

CO based on supplementary external energy 2. Energy storage device and method for gas-liquid phase transition technical field

The present invention relates to the technical field of energy storage, in particular to an energy storage device and method for _CO2 gas-liquid phase transition based on supplementary external energy.

Background technique

With the development of society and economy, people's demand for energy is increasing, but the increase in energy consumption has made environmental problems more serious, and non-renewable traditional energy sources such as coal and oil are increasingly exhausted. New energy sources such as solar energy and wind energy are vigorously developed To slow down the traditional energy consumption has become an inevitable choice. However, due to the intermittent and fluctuating characteristics of new energy sources such as solar energy and wind energy, their effective utilization is far from sufficient. Therefore, it is necessary to use energy storage technology to optimize and adjust the energy system.

In the related art, there is a way of energy storage by compressing carbon dioxide. Its main principle is to use excess electricity to compress carbon dioxide and store it during the low electricity consumption period. During the peak period of electricity consumption, it is released and the turbine is used to drive the generator to output electricity, so as to make full use of the energy and reduce the impact of the intermittent power generation of new energy on the power grid. However, in the natural environment and in industrial and agricultural production, there are many external thermal energies, such as solar thermal energy and thermal energy generated by waste incineration, which are usually directly wasted, resulting in great waste.

SUMMARY OF THE INVENTION

Based on this, the present invention proposes a CO ₂ gas-liquid phase transition energy storage device based on supplementing external energy, which can supplement the energy input to the expander by using heat sources such as solar thermal energy and thermal energy generated by waste incineration, thereby reducing resource waste. ,Energy saving.

Energy storage devices based on the gas-liquid phase transition of _CO2 supplemented with external energy, including:

a gas storage, the gas storage is used for storing gaseous carbon dioxide, and the volume of the gas storage can be changed;

a liquid storage tank, the liquid storage tank is used for storing liquid carbon dioxide;

an energy storage assembly, the energy storage assembly is used to store energy, the energy storage assembly is arranged between the gas storage and the liquid storage tank, and carbon dioxide is converted from a gaseous state to a liquid state through the energy storage assembly;

An energy release assembly, the energy release assembly is arranged between the gas storage and the liquid storage tank, the energy release component includes a plurality of expansion energy release parts, and the expansion energy release part includes an energy release heat exchanger , Supplementary energy heat exchanger and expander, the supplementary energy heat exchanger is provided between the energy release heat exchanger and the expander in each of the expansion energy release parts, and the expander uses For releasing energy, carbon dioxide is converted from liquid state to gaseous state through the energy releasing component;

a heat exchange assembly, the energy storage assembly and the energy release assembly are both connected to the heat exchange assembly, and the heat exchange assembly can transfer part of the energy generated in the energy storage assembly to the energy release assembly;

An energy supplement component, the energy supplement component includes an external heat source, a plurality of the supplementary energy heat exchangers are all connected to the external heat source, and the external heat source supplements energy to the expander through the supplementary energy heat exchanger.

In one embodiment, the energy supplement component further includes an inflow pipeline and an outflow pipeline, an energy supplement medium is arranged in the inflow pipeline and the outflow pipeline, and the plurality of supplementary energy heat exchangers are The inflow line is connected to the external heat source, the energy supplementary medium flows from the external heat source to the supplementary energy heat exchanger through the inflow line, and a plurality of the supplementary energy heat exchangers pass through The outflow line is connected to the external heat source, and the energy supplementary medium flows from the supplementary energy heat exchanger to the external heat source through the outflow line.

In one of the embodiments, a plurality of the expanders are arranged coaxially.

In one embodiment, the energy release component further includes an evaporator and an energy release cooler, carbon dioxide is converted from liquid to gaseous state through the evaporator, and the energy release cooler is used for cooling the carbon dioxide entering the gas storage. For cooling, the energy release heat exchanger in the expansion energy release part at the beginning is connected to the evaporator, and the expander in the expansion energy release part at the end is connected to the energy release cooler, The expander in each expansion energy release part is connected with the energy release heat exchanger in the adjacent expansion energy release part.

In one of the embodiments, the energy release cooler is connected to the evaporator.

In one of the embodiments, the energy release assembly further includes an evaporator, and the external heat source is connected to the evaporator.

In one embodiment, the heat exchange assembly includes a cold storage tank and a heat storage tank, and a heat exchange medium is arranged in the cold storage tank and the heat storage tank, and the cold storage tank and the heat storage tank are provided with a heat exchange medium. A heat exchange circuit is formed between the energy storage component and the energy release component, the heat exchange medium can flow in the heat exchange circuit, and the heat exchange medium flows from the cold storage tank to the storage tank When a heat storage tank is used, part of the energy generated by the energy storage assembly can be stored, and when the heat exchange medium flows from the heat storage tank to the cold storage tank, the stored energy can be transferred to the energy release assembly.

In one embodiment, an auxiliary heating element is provided between the cold storage tank and the heat storage tank, and part of the heat exchange medium can flow into the heat storage tank after being heated by the auxiliary heating element.

In one embodiment, the energy release component includes an evaporator through which carbon dioxide is converted from liquid to gaseous state, and the heat exchange component further includes a heat exchange medium cooler for cooling the carbon dioxide. The heat exchange medium entering the cold storage tank is cooled, and the heat exchange medium cooler is connected to the evaporator.

In one of the embodiments, the energy storage assembly includes a condenser and a compression energy storage part, at least one set of the compression energy storage part is provided, and the compression energy storage part includes a compressor and an energy storage heat exchanger, each of which is The energy storage heat exchanger in the compression energy storage part is connected to the compressor, and the energy storage heat exchanger in each compression energy storage part is connected to the adjacent compression energy storage part. The compressor at the beginning end is connected with the gas storage, the compressor in the compression energy storage part at the beginning end is connected with the gas storage, and the energy storage heat exchanger in the compression energy storage part at the end is connected with the condenser The liquid storage tank is connected to the condenser, the heat exchange component is connected to the energy storage heat exchanger, and the energy storage heat exchanger can compress the carbon dioxide produced by the compressor. Energy is transferred to the heat exchange assembly.

In one embodiment, the energy release assembly includes a throttle expansion valve and an evaporator, through which carbon dioxide is converted from liquid state to gaseous state, and the throttle expansion valve is located between the liquid storage tank and the evaporator In between, the throttling expansion valve is used to depressurize the carbon dioxide flowing out of the liquid storage tank;

The energy storage assembly includes a condenser through which carbon dioxide is converted from gaseous state to liquid state, and the evaporator is connected with the condenser.

In one embodiment, the gas storage is a flexible membrane gas storage.

The above-mentioned energy storage device based on the gas-liquid phase transition of _CO2 supplemented with external energy is provided with a gas storage and a liquid storage tank. The gaseous carbon dioxide is stored in the gas storage, and the liquid carbon dioxide is stored in the liquid storage tank. An energy storage component and an energy release component are arranged between the gas storage and the liquid storage tank, and a heat exchange component is also arranged between the energy release component and the energy storage component. The carbon dioxide changes from gaseous state to liquid state when passing through the energy storage component, and changes from liquid state to gaseous state when passing through the energy releasing component. When carbon dioxide reaches the liquid storage tank from the gas storage through the energy storage component, the energy storage is completed, part of the energy is stored in the carbon dioxide, part of the energy is stored in the heat exchange component, and transferred to the energy release component, and the energy release is completed through the energy release component. . In the energy release module, a supplementary energy heat exchanger is arranged between each energy release heat exchanger and the expander. If the energy stored in the energy storage process is insufficient, the supplementary heat provided by the external heat source can be input through the supplementary energy heat exchanger. to the expander. The supplementary heat provided by external heat sources such as solar thermal energy and thermal energy generated by waste incineration can be input to the expander through the supplementary energy heat exchanger to do external work, thereby reducing waste of resources and saving energy.

The invention also proposes an energy storage method based on the gas-liquid phase transition of CO ₂ supplementing external energy, which can supplement the energy input to the expander so that it has enough energy to do external work.

An energy storage device based on the gas-liquid phase transition of _CO2 supplemented with external energy, including an energy storage step and an energy release step,

In the energy storage step, carbon dioxide is changed from gaseous state to liquid state, and part of the energy is stored in the heat exchange medium;

In the energy releasing step, carbon dioxide changes from liquid state to gaseous state, the energy stored in the heat exchange medium is released through carbon dioxide, and when energy is released, energy is supplemented by an external heat source.

The above-mentioned energy storage device based on the gas-liquid phase change of _CO2 supplemented by external energy, in the process of energy storage, carbon dioxide is converted from gaseous state to liquid state, and part of the energy generated is stored in the heat exchange medium. This part of the energy is released, and when the energy is released, the heat sources such as solar thermal energy and thermal energy generated by waste incineration supplement the energy to do external work, thereby reducing waste of resources and saving energy.

Description of drawings

FIG. 1 is a schematic structural diagram of an energy storage device for gas-liquid phase transition of CO ₂ based on supplementary external energy in an embodiment of the present invention.

Reference number:

gas storage 100;

liquid storage tank 200;

The energy storage assembly 300, the first compressor 310, the first energy storage heat exchanger 320, the second compressor 330, the second energy storage heat exchanger 340, the third compressor 350, the third energy storage heat exchanger 360, Condenser 370, first energy storage pipeline 381, energy storage second pipeline 382, energy storage third pipeline 383, energy storage fourth pipeline 384, energy storage fifth pipeline 385, energy storage sixth pipeline 386, energy storage seventh The pipeline 387, the eighth pipeline 388 for energy storage, the electric motor 390;

Energy release assembly 400 , evaporator 410 , first energy release heat exchanger 421 , first supplemental energy heat exchanger 422 , first expander 423 , second energy release heat exchanger 431 , second supplementary energy heat exchanger 432 , the second expander 433, the third energy release heat exchanger 441, the third supplementary energy heat exchanger 442, the third expander 443, the energy release cooler 450, the energy release first pipeline 461, and the energy release second pipeline 462 , the third channel of energy release 463, the fourth channel of energy release 464, the fifth channel of energy release 465, the sixth channel of energy release 466, the seventh channel of energy release 467, the eighth channel of energy release 468, the ninth channel of energy release 469, Tenth energy release pipeline 4610, energy release eleventh pipeline 4611, energy release twelfth pipeline 4612, energy release thirteenth pipeline 4613, throttle expansion valve 470, generator 480;

Heat exchange assembly 500, cold storage tank 510, heat storage tank 520, heat exchange medium cooler 530, first heat exchange pipe 541, second heat exchange pipe 542, third heat exchange pipe 543, fourth heat exchange pipe 544, The first circulating pump 550 for heat exchange medium and the second circulating pump 551 for heat exchange medium;

First valve 610, second valve 620, third valve 630, fourth valve 640, fifth valve 650, sixth valve 660, seventh valve 670, eighth valve 680, ninth valve 6200;

a pool 710, a first recovery pipeline 720, a second recovery pipeline 730, a third recovery pipeline 740, a fourth recovery pipeline 750, a fifth recovery pipeline 760, and a sixth recovery pipeline 770;

An energy supplement component 800 , an external heat source 810 , an energy supplement medium heater 820 , an inflow pipeline 830 , and an outflow pipeline 840 .

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", " Back, Left, Right, Vertical, Horizontal, Top, Bottom, Inner, Outer, Clockwise, Counterclockwise, Axial , "radial", "circumferential" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the indicated device or Elements must have a particular orientation, be constructed and operate in a particular orientation and are therefore not to be construed as limitations of the invention.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined.

In the present invention, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between the two elements, unless otherwise specified limit. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In the present invention, unless otherwise expressly specified and limited, a first feature "on" or "under" a second feature may be in direct contact between the first and second features, or the first and second features indirectly through an intermediary touch. Also, the first feature being "above", "over" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or an intervening element may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for the purpose of illustration only and do not represent the only embodiment.

Referring to FIG. 1 , FIG. 1 shows a schematic structural diagram of an energy storage device for CO ₂ gas-liquid phase transition based on supplementary external energy in an embodiment of the present invention. The energy storage device for CO ₂ gas-liquid phase transition based on supplementary external energy provided by an embodiment of the present invention includes a gas storage 100 , a liquid storage tank 200 , an energy storage component 300 , an energy release component 400 , a heat exchange component 500 and an energy supplement Assembly 800 and other components.

Liquid carbon dioxide in a high pressure state is stored in the liquid storage tank 200 . The gas storage 100 stores gaseous carbon dioxide at normal temperature and pressure, and the pressure and temperature inside the gas storage 100 are maintained within a certain range to meet the energy storage requirements. Specifically, a heat preservation device is provided to heat the gas storage 100, so that the temperature inside the gas storage tank 100 is maintained within a required range. According to the ideal gas equation of state PV=nRT, when the temperature and pressure are constant, the volume is proportional to the amount of matter. Therefore, the gas storage 100 adopts an air film gas storage, and its volume can be changed. When carbon dioxide is charged, the volume of the gas storage 100 increases, and when carbon dioxide flows out, the volume of the gas storage 100 decreases, so as to reduce the volume of the gas storage. In this way, the pressure in the gas storage 100 can be kept constant. It should be noted that the pressure and temperature inside the gas storage 100 are maintained within a certain range, and in the above analysis, they are approximately regarded as constant values.

Specifically, the temperature T ₁ in the gas storage 100 is in the range of 15° C.≦T ₁ ≦35° C. The pressure difference between the air pressure in the gas storage 100 and the outside atmosphere is less than 1000Pa.

The energy storage assembly 300 is located between the gas storage 100 and the liquid storage tank 200. The gaseous carbon dioxide flowing out of the gas storage 100 is converted into a liquid state through the energy storage assembly 300 and flows into the liquid storage tank 200, completing energy storage in the process.

The energy release assembly 400 is also located between the gas storage 100 and the liquid storage tank 200. The liquid carbon dioxide flowing out from the liquid storage tank 200 is transformed into a gaseous state through the energy release assembly 400 and flows into the gas storage 100. The energy stored in the energy process is released.

The heat exchange component 500 is disposed between the energy storage component 300 and the energy release component 400 . During the energy storage process, a part of the stored energy is stored in the high-pressure liquid carbon dioxide in the form of pressure energy, and the other part is stored in the heat exchange component 500 in the form of thermal energy. During the energy release process, this part of the energy is transferred from the heat exchange component 500 to the energy release component 400, and all the stored energy is released through gaseous carbon dioxide.

Specifically, the energy release assembly 400 includes at least two expansion energy release parts, and the expansion energy release part includes an expander, a supplementary energy heat exchanger, and an energy release heat exchanger. In each expansion energy release part, a supplementary energy heat exchanger is arranged between the energy release heat exchanger and the expander. The energy release heat exchanger is connected to the heat exchange component 500, and the energy stored in the heat exchange component 500 during the energy storage process is transferred to the carbon dioxide flowing through the energy release heat exchanger through the energy release heat exchanger. The supplementary energy heat exchanger is connected to the external heat source and can absorb the external heat energy provided by the external heat source. When carbon dioxide flows to the supplementary energy heat exchanger, it absorbs the external heat energy transferred from the external heat source to the supplementary energy heat exchanger, and finally, the energy stored in the energy storage process and the external input energy are released to do external work through the expander.

The external heat source 810 may be waste heat, for example, heat released when castings or forgings in a foundry or forge are cooled, or may be heat released during chemical reactions in a chemical plant, or may be gas turbine waste heat. Using waste heat as an external heat source reduces energy waste. Of course, it can also be solar energy or geothermal energy.

The energy storage device in this embodiment can convert carbon dioxide from a gaseous state to a liquid state by using excess power output by the power plant to store energy during a low electricity consumption period. During the peak period of electricity consumption, this part of the energy is released to drive the generator 480 to generate electricity. In this way, it can not only reduce energy waste, but also earn the electricity price difference between the valley period of electricity consumption and the peak period of electricity consumption, and the economic benefits are considerable. In addition, the external heat source can be used to supplement the energy on the energy release path, so as to increase the external power and reduce the waste of resources.

In the energy storage device in this embodiment, carbon dioxide only changes between gaseous state and liquid state. Before energy storage, carbon dioxide is in a gaseous state and is at normal temperature and pressure. Compared with the conventional energy storage and energy release through supercritical carbon dioxide, In this embodiment, the requirements for the gas storage 100 are relatively low, and there is no need to provide storage components with complex structures, which can reduce costs to a certain extent.

In some embodiments, the energy storage assembly 300 includes a condenser 370 and at least one set of compression energy storage units, the compression energy storage unit includes a compressor and an energy storage heat exchanger, and the compressor and energy storage unit in each set of compression energy storage units heat exchanger connection. The energy storage heat exchangers in each group of compression energy storage parts are connected to the compressors in the adjacent compression energy storage parts. The compressor in the compression energy storage part at the beginning is connected to the gas storage 100 , and the energy storage heat exchanger in the compression energy storage part at the end is connected to the condenser 370 . The start and end here are defined by the direction from the gas storage 100 through the energy storage assembly 300 to the liquid storage tank 200 . If there is only one set of compression energy storage parts, the beginning and the end are the only one set of compression energy storage parts. The excess power output from the grid drives the compressor to work through the motor 390 to realize energy input.

Specifically, in some embodiments, the energy storage assembly 300 includes a first compressor 310, a first energy storage heat exchanger 320, a second compressor 330, a second energy storage heat exchanger 340, a third compressor 350, The third energy storage heat exchanger 360 and the condenser 370 and other components. The first compressor 310 and the gas storage 100 are connected through a first energy storage pipeline 381, and the first energy storage heat exchanger 320 and the first compressor 310 are connected through an energy storage second pipeline 382, and the second compressor 330 and the first energy storage heat exchanger 320 are connected through a third energy storage pipeline 383, and the second energy storage heat exchanger 340 and the second compressor 330 are connected through an energy storage fourth pipeline 384, and the third compressor 350 and the second energy storage heat exchanger 340 are connected through an energy storage fifth pipeline 385, the third energy storage heat exchanger 360 and the third compressor 350 are connected through an energy storage sixth pipeline 386, and the condenser 370 is connected to The third energy storage heat exchangers 360 are connected through an energy storage seventh pipeline 387 , and the liquid storage tank 200 and the condenser 370 are connected through an energy storage eighth pipeline 388 .

The heat exchange assembly 500 is connected to the first energy storage heat exchanger 320, the second energy storage heat exchanger 340, and the third energy storage heat exchanger 360, and the first compressor 310, the second compressor 330, and the third compressor Part of the energy generated when 350 compresses carbon dioxide is stored in the high-pressure carbon dioxide in the form of pressure energy, and part of the energy passes through the first energy storage heat exchanger 320, the second energy storage heat exchanger 340 and the third energy storage heat exchanger in the form of thermal energy. 360 is transferred to the heat exchange assembly 500 for temporary storage.

In the above structure, a three-stage compression is provided, and the carbon dioxide is gradually pressurized by the three-stage compression. Compared with the first compression in place, when the third compression is performed, a compressor with a smaller compression ratio can be selected, and the cost of the compressor is lower. Of course, the number of compressors can also be one, two or more than three, as long as the compressor and the energy storage heat exchanger are increased or decreased as a complete set.

In some embodiments, the energy release assembly 400 includes an evaporator 410 , at least two expansion energy release parts, an energy release cooler 450 and other components. The expander in each expansion energy release section is connected to the energy release heat exchanger in the adjacent expansion energy release section. The energy release heat exchanger in the expansion energy release part at the beginning is connected to the evaporator 410 , and the expander in the expansion energy release part at the end is connected to the energy release cooler 450 . The start and end here are defined by the direction from the liquid storage tank 200 through the energy release assembly 400 to the gas storage 100 .

Specifically, in some embodiments, the energy release assembly 400 includes an evaporator 410 , a first energy release heat exchanger 421 , a first supplementary energy heat exchanger 422 , a first expander 423 , and a second energy release heat exchanger 431 , the second supplementary energy heat exchanger 432, the second expander 433, the third energy release heat exchanger 441, the third supplementary energy heat exchanger 442, the third expander 443 and the energy release cooler 450 and other components. The evaporator 410 and the liquid storage tank 200 are connected through a first energy releasing pipeline 461 . The first energy releasing heat exchanger 421 and the evaporator 410 are connected through an energy releasing second pipeline 462, and the first supplementary energy heat exchanger 422 and the first energy releasing heat exchanger 421 are connected through an energy releasing third pipeline 463 , the first expander 423 and the first supplementary energy heat exchanger 422 are connected through a fourth energy release pipeline 464 . The second energy releasing heat exchanger 431 and the first expander 423 are connected by the energy releasing fifth pipeline 465, and the second supplementary energy heat exchanger 432 and the second energy releasing heat exchanger 431 are connected by the energy releasing sixth pipeline 466 is connected, and the second expander 433 and the second supplementary energy heat exchanger 432 are connected through an energy releasing seventh pipeline 467 . The third energy releasing heat exchanger 441 and the second expander 433 are connected through the energy releasing eighth pipeline 468, and the third supplementary energy heat exchanger 442 and the third energy releasing heat exchanger 441 are connected through the energy releasing ninth pipeline 469 is connected, and the third expander 443 and the third supplementary energy heat exchanger 442 are connected through the tenth pipeline 4610 for releasing energy. The energy releasing cooler 450 and the third expander 443 are connected through the energy releasing eleventh pipeline 4611 . The gas storage 100 and the energy releasing cooler 450 are connected through a twelfth energy releasing pipeline 4612 .

The heat exchange component 500 is connected to the first energy release heat exchanger 421, the second energy release heat exchanger 431, and the third energy release heat exchanger 441. During the energy release process, the energy temporarily stored in the heat exchange component 500 The first energy release heat exchanger 421, the second energy release heat exchanger 431, and the third energy release heat exchanger 441 are transferred to flow through the first energy release heat exchanger 421, the second energy release heat exchanger 431, and the third energy release heat exchanger 441. In the carbon dioxide in the three-energy-releasing heat exchanger 441 , the carbon dioxide absorbs this part of the energy, and releases the energy through the first expander 423 , the second expander 433 , and the third expander 443 .

In the energy release assembly 400, the energy is released by the first expander 423, the second expander 433, and the third expander 443, and the generator 480 is driven to generate electricity. When the gaseous carbon dioxide flows through the first expander 423, the second expander 433, and the third expander 443, it impacts the blades and pushes the rotor to rotate, so as to achieve energy output.

In the above-mentioned structure, three expanders are set up to release energy three times. When three expanders are set to release energy together, the requirements for manufacturing the blades of the expander are lower, and the cost is correspondingly lower. Of course, the number of expanders can also be one, two or more than three, as long as the expanders and the energy releasing heat exchangers can be increased or decreased as a complete set.

The external heat source 810 is connected to the first supplementary energy heat exchanger 422 , the second supplementary energy heat exchanger 432 , and the third supplementary energy heat exchanger 442 . Part of the heat provided by the external heat source is input to the first expander 423 through the first supplementary energy heat exchanger 422, part of the heat is input to the second expander 433 through the second supplementary energy heat exchanger 432, and part of the heat is passed through the third supplementary energy exchange. The heater 442 is input to the third expander 443 .

In this way, when the first expander 423, the second expander 433, and the third expander 443 do external work to release energy, part of the energy source is the energy stored during the energy storage process, and part is the external heat source through the first supplementary energy exchange. Heat input from the heat exchanger 422 , the second supplemental energy heat exchanger 432 , and the third supplementary energy heat exchanger 442 .

Preferably, the above-mentioned first expander 423, second expander 433, and third expander 443 are coaxially arranged, so that the axial force can be balanced, the axial vibration can be reduced, and the entire device can be run more smoothly, with less vibration and noise. Also smaller.

Specifically, in some embodiments, the heat exchange assembly 500 includes components such as a cold storage tank 510 , a heat storage tank 520 , and a heat exchange medium cooler 530 . Heat exchange medium is stored in the cold storage tank 510 and the heat storage tank 520 . The cold storage tank 510 and the heat storage tank 520 form a heat exchange circuit between the energy storage assembly 300 and the energy release assembly 400, and the heat exchange medium can circulate in the heat exchange circuit. The above-mentioned heat exchange medium can be selected from materials such as molten salt or saturated water.

The temperature of the heat exchange medium in the cold storage tank 510 is lower, and the temperature of the heat exchange medium in the heat storage tank 520 is higher. When the heat exchange medium flows between the cold storage tank 510 and the heat storage tank 520, the collection and release of heat can be realized. Specifically, when the heat exchange medium flows from the cold storage tank 510 to the heat storage tank 520, it absorbs part of the heat generated during the energy storage process, and when the heat exchange medium flows from the heat storage tank 520 to the cold storage tank 510, it absorbs the previously absorbed heat Then, when the heat exchange medium flows from the heat storage tank 520 to the cold storage tank 510 , it flows through the heat exchange medium cooler 530 for cooling, so as to meet the temperature requirement of the heat exchange medium stored in the cold storage tank 510 .

The energy supplement assembly 800 includes an external heat source 810 , an energy supplement medium heater 820 , an inflow pipeline 830 and an outflow pipeline 840 and other components. The inflow line 830 and the outflow line 840 contain an energy supplement medium. The external heat source 810 may heat the energy supplementary medium heater 820 . The first supplementary energy heat exchanger 422, the second supplementary energy heat exchanger 432, and the third supplementary energy heat exchanger 442 are all connected to the inflow pipeline 830, and the first supplementary energy heat exchanger 422 and the second supplementary energy heat exchanger Both the heat exchanger 432 and the third supplemental energy heat exchanger 442 are connected to the outflow pipeline 840 .

When external energy needs to be supplemented on the energy release path, the eighth valve 680 is opened, and the energy supplement medium heater 820 is heated by the external heat source 810, so that the energy supplement medium is heated in the energy supplement medium heater 820, and flows along the inflow pipe. Path 830 is split into the first supplemental energy heat exchanger 422 , the second supplemental energy heat exchanger 432 and the third supplemental energy heat exchanger 442 . After being heated, the energy supplement medium in a high temperature state flows through the first supplementary energy heat exchanger 422, the second supplementary energy heat exchanger 432 and the third supplementary energy heat exchanger 442 for heat exchange, and transfers the heat to the first supplementary energy heat exchanger 422, the second supplementary energy heat exchanger 432 and the third supplementary energy heat exchanger 442. The carbon dioxide in the first supplementary energy heat exchanger 422, the second supplementary energy heat exchanger 432 and the third supplementary energy heat exchanger 442 increases the temperature of the carbon dioxide. After the heat exchange is completed, the energy supplement medium is returned to the energy supplement medium heater 820 through the outflow pipeline 840 . Repeating the above process, the supplementary energy medium circulates between the three supplementary energy heat exchangers and the supplementary energy medium heater 820 to realize the input of supplementary heat. The above-mentioned energy supplement medium can be a material such as heat-conducting oil or molten salt.

In addition, components such as circulating pumps are arranged on each of the above-mentioned pipelines to realize the directional flow of carbon dioxide, heat exchange medium or energy supplementary medium.

When storing energy, the first valve 610 and the third valve 630 are opened, and the second valve 620 and the fourth valve 640 are closed. The gaseous carbon dioxide in the normal temperature and pressure state flows out from the gas storage 100 and flows to the first compressor 310 through the energy storage first pipeline 381 . The gaseous carbon dioxide is first compressed by the first compressor 310 to increase its pressure. During the compression process, heat is generated, raising the temperature of the carbon dioxide. After being compressed by the first compressor 310 , the carbon dioxide flows to the first energy storage heat exchanger 320 through the energy storage second pipeline 382 , and transfers the heat generated during compression to the first energy storage heat exchanger 320 . The first energy storage heat exchanger 320 transfers heat to the heat exchange medium. The carbon dioxide flowing out from the first energy storage heat exchanger 320 flows to the second compressor 330 through the energy storage third pipeline 383, and is compressed for a second time by the second compressor 330 to further increase its pressure. During the compression process, heat is generated, raising the temperature of the carbon dioxide. After being compressed by the second compressor 330 , the carbon dioxide flows to the second energy storage heat exchanger 340 through the energy storage fourth pipeline 384 , and transfers the heat generated during compression to the second energy storage heat exchanger 340 . The second energy storage heat exchanger 340 transfers heat to the heat exchange medium. The carbon dioxide flowing out from the second energy storage heat exchanger 340 flows to the third compressor 350 through the energy storage fifth pipeline 385, and is compressed for the third time by the third compressor 350 to further increase its pressure. During the compression process, heat is generated, raising the temperature of the carbon dioxide. After being compressed by the third compressor 350 , the carbon dioxide flows to the third energy storage heat exchanger 360 through the energy storage sixth pipeline 386 , and transfers the heat generated during compression to the third energy storage heat exchanger 360 . The third energy storage heat exchanger 360 transfers heat to the heat exchange medium. After the heat exchange is achieved, the high-pressure gaseous carbon dioxide flows to the condenser 370 through the seventh energy storage pipeline 387, and is condensed by the condenser 370 to be converted into liquid carbon dioxide. The liquid carbon dioxide flows into the liquid storage tank 200 through the eighth energy storage pipeline 388 to complete the energy storage process.

When releasing energy, the second valve 620 and the fourth valve 640 are opened, the first valve 610 and the third valve 630 are closed, and the eighth valve 680 is opened at the same time. The high-pressure liquid carbon dioxide flows out from the liquid storage tank 200, and flows to the evaporator 410 through the first energy release pipeline 461, evaporates through the evaporator 410, and turns into a gaseous state. The gaseous carbon dioxide flows to the first energy-releasing heat exchanger 421 via the energy-releasing second conduit 462 . During the energy storage process, part of the heat stored in the heat exchange medium is transferred to the carbon dioxide flowing through the first energy release heat exchanger 421 through the first energy release heat exchanger 421 , and the carbon dioxide absorbs this part of the heat and the temperature increases. The heated carbon dioxide flows to the first supplementary energy heat exchanger 422 through the third energy release pipe 463, and absorbs the supplementary heat input from the external heat source 810 through the first supplementary energy heat exchanger 422, and further heats up. The high-temperature gaseous carbon dioxide flows to the first expander 423 through the fourth pipe 464 for releasing energy, expands in the first expander 423 and performs external work to realize energy output and drive the generator to generate electricity. After the first energy release is completed, the carbon dioxide flows out from the first expander 423, and the temperature and pressure decrease.

The carbon dioxide flowing out from the first expander 423 flows to the second energy releasing heat exchanger 431 through the energy releasing fifth conduit 465 . During the energy storage process, part of the heat stored in the heat exchange medium is transferred to the carbon dioxide flowing through the second energy release heat exchanger 431 through the second energy release heat exchanger 431 , and the carbon dioxide absorbs this part of the heat and the temperature increases. The heated carbon dioxide flows to the second supplementary energy heat exchanger 432 through the sixth energy release pipe 466, and absorbs the supplementary heat input from the external heat source 810 through the second supplementary energy heat exchanger 432, and further heats up. The high-temperature gaseous carbon dioxide flows to the second expander 433 through the seventh energy release pipeline 467, expands in the second expander 433 and performs external work to achieve energy output and drive the generator to generate electricity. After the second energy release is completed, the carbon dioxide flows out from the second expander 433, and the temperature and pressure decrease.

The carbon dioxide flowing out from the second expander 433 flows to the third energy-releasing heat exchanger 441 through the energy-releasing eighth pipeline 468 . During the energy storage process, part of the heat stored in the heat exchange medium is transferred to the carbon dioxide flowing through the third energy release heat exchanger 441 through the third energy release heat exchanger 441, and the carbon dioxide absorbs this part of the heat and the temperature increases. The heated carbon dioxide flows to the third supplementary energy heat exchanger 442 through the ninth energy release pipeline 469, and absorbs the supplementary heat input from the external heat source 810 through the third supplementary energy heat exchanger 442, and further heats up. The high-temperature gaseous carbon dioxide flows to the third expander 443 through the tenth pipeline 4610 for energy release, expands in the third expander 443 and performs external work to achieve energy output and drive the generator to generate electricity. After the third energy release is completed, the carbon dioxide flows out from the third expander 443, and the temperature and pressure decrease.

The pressure and temperature of carbon dioxide after the three-time energy release are reduced, but the temperature is still higher than the storage temperature required by the gas storage 100 . Therefore, the carbon dioxide flowing out of the third expander 443 flows into the energy releasing cooler 450 through the energy releasing eleventh pipeline 4611 , and the energy releasing cooler 450 cools it down so that its temperature can meet the requirements of the gas storage 100 . The cooled carbon dioxide flows into the gas storage 100 through the twelfth energy release pipeline 4612 to complete the entire energy release process.

In the above process, the thermal energy stored in the heat exchange assembly 500 and the thermal energy input from the external heat source 810 are merged into the high-pressure carbon dioxide, and the carbon dioxide is in the first expander 423 , the second expander 433 and the third expander 443 . Expansion releases pressure energy together with thermal energy into mechanical energy.

In the above-mentioned energy storage and energy release process, the first circulation pump 550 of the heat exchange medium is turned on when the energy is stored, and the second circulation pump 551 of the heat exchange medium is turned on when the energy is released. Circulating flow between, realizing the temporary storage and release of energy. Specifically, the energy is temporarily stored in the heat exchange medium in the form of heat energy. During the energy storage process, after the low-temperature heat exchange medium flows out of the cold storage tank 510, it is split through the first heat exchange pipeline 541 to reach the first energy storage heat exchanger 320, the second energy storage heat exchanger 340, and the third energy storage heat exchanger Heat exchange occurs at heat exchanger 360 . The heat exchange medium flowing through the first energy storage heat exchanger 320 absorbs the heat in the carbon dioxide compressed for the first time, so that the temperature of this part of the heat exchange medium increases. The heat exchange medium flowing through the second energy storage heat exchanger 340 absorbs the heat in the carbon dioxide compressed for the second time, so that the temperature of this part of the heat exchange medium increases. The heat exchange medium flowing through the third energy storage heat exchanger 360 absorbs the heat in the carbon dioxide compressed for the third time, so that the temperature of this part of the heat exchange medium increases. After the heat exchange medium absorbs heat, it all flows into the second heat exchange pipeline 542 and flows into the heat storage tank 520 , and the heat is temporarily stored in the heat storage tank 520 .

When releasing energy, after the high-temperature heat exchange medium flows out of the heat storage tank 520, it is divided into the first energy release heat exchanger 421, the second energy release heat exchanger 431, and the third energy release heat exchange through the third heat exchange pipeline 543. Heat exchange is performed at the device 441 . The heat is transferred to the carbon dioxide flowing through the first energy release heat exchanger 421, the second energy release heat exchanger 431, and the third energy release heat exchanger 441 to increase its temperature. After the heat exchange is completed, the temperature of the heat exchange medium decreases, and the cooled heat exchange medium flows to the cold storage tank 510 through the fourth heat exchange pipeline 544 . Although the temperature of the heat exchange medium decreases after heat exchange, its temperature is still higher than the temperature range required by the cold storage tank 510 . Therefore, when this part of the heat exchange medium flows through the heat exchange medium cooler 530 through the heat exchange fourth pipe 544 , it is cooled again by the heat exchange medium cooler 530 to make its temperature meet the requirements of the cold storage tank 510 .

In addition, in some embodiments, all of the first valve 610 , the second valve 620 , the third valve 630 , and the fourth valve 640 may be opened, and energy storage and energy release are performed simultaneously. The above situation may exist when the low power consumption period is coming to an end and the power consumption peak period is about to come. Moreover, when operating at the same time, power with large frequency fluctuations such as wind power can be adjusted to a relatively stable power.

In the aforementioned manner, the heat provided by the external heat source 810 is directly supplemented to the energy release process, and the carbon dioxide is heated just before it enters each expander. In addition to this, external heat can also be supplemented at other locations.

For example, in some embodiments, an external heat source 810 may be connected to the evaporator 410 to provide the heat required for carbon dioxide vaporization through the external heat source 810 .

Alternatively, in some embodiments, a heating pipe may be provided between the cold storage tank 510 and the heat storage tank 520, and an auxiliary heating element may be provided on the heating pipe. A part of the heat exchange medium flowing out of the cold storage tank 510 flows to the auxiliary heating element through the heating pipe, and the auxiliary heating element heats this part of the heat exchange medium to absorb external heat, so that it can reach the first energy releasing heat exchanger 421 The heat at the second energy releasing heat exchanger 431 and the third energy releasing heat exchanger 441 increases, that is, the heat that can be provided to the first expander 423 , the second expander 433 and the third expander 443 increases. The heat source at the auxiliary heating element can also be waste heat.

In the above-mentioned energy storage and energy release process, in addition to the energy that needs to be stored during the energy storage process, some excess energy is also generated in some steps, and the same is true in the energy release process. Usually, these energies are directly released, which will add up to a larger waste of energy. Preferably, in some embodiments, the excess energy is recycled again, so that the energy can be used for the evaporation of carbon dioxide. In this way, energy waste in the process of energy storage and energy release can be reduced, energy utilization can be improved, and costs can be reduced.

For example, in some embodiments, after the heat exchange medium is cooled by the heat exchange medium cooler 530, the released heat can be recovered and used for carbon dioxide evaporation to reduce energy waste and improve energy utilization.

Specifically, the heat exchange medium cooler 530 can be connected to the evaporator 410, and the heat released when the heat exchange medium cooler 530 cools the heat exchange medium can be transferred to the evaporator 410 for use in evaporating carbon dioxide. The heat exchange medium cooler 530 and the evaporator 410 may be directly connected or indirectly connected through other components.

Of course, if only the heat exchange medium cooler 530 is used to evaporate the heat released during the cooling of the heat exchange medium, there may be insufficient heat. Therefore, an external heat source can also be used to supplement heat so that the evaporation process can proceed smoothly.

Preferably, the supplemental external heat source may be waste heat. Using waste heat as an external heat source can reduce energy waste and eliminate the need for additional heating, thereby reducing costs.

In some embodiments, during the energy storage process, the heat released during condensation through the condenser 370 can be recycled, and during the energy release process, this part of the heat is supplied to the evaporator 410 for use in evaporating carbon dioxide to reduce energy waste, Improve energy utilization.

Specifically, the condenser 370 can be connected to the evaporator 410 to collect the heat released when the carbon dioxide is condensed, and transferred to the evaporator 410 for use in the evaporation of the carbon dioxide. The condenser 370 and the evaporator 410 may be directly connected or indirectly connected through other components.

Of course, if only the heat released by the condenser 370 is used for evaporation, there may be insufficient heat. Therefore, an external heat source can also be used to supplement heat so that the evaporation process can proceed smoothly.

Preferably, in some embodiments, a first energy releasing pipeline 461 and a thirteenth energy releasing pipeline 4613 are arranged between the evaporator 410 and the liquid storage tank 200 , and a second valve 620 is arranged on the first energy releasing pipeline 461 , A throttle expansion valve 470 and a ninth valve 6200 are arranged on the thirteenth pipeline 4613 of the energy release. When the second valve 620 is opened and the ninth valve 6200 is closed, the first pipe 461 for releasing energy is connected, and when the ninth valve 6200 is opened, and when the second valve 620 is closed, the thirteenth pipe 4613 for releasing energy is connected. During the energy release process, if the thirteenth energy release pipeline 4613 is selected to be turned on, the high-pressure liquid carbon dioxide flowing out of the liquid storage tank 200 is expanded and depressurized through the throttle expansion valve 470 , and then flows into the evaporator 410 .

Setting the throttling expansion valve 470 for depressurization facilitates the conversion of carbon dioxide from liquid to gaseous state, compared to merely increasing the temperature to convert carbon dioxide from liquid to gaseous state.

Preferably, when the throttling expansion valve 470 is used, the evaporator 410 and the condenser 370 can be combined, and the two can be combined into one component to form a phase change heat exchanger. The phase change heat exchanger includes an evaporation part and a condensation part. The evaporation part and the condensation part are connected by pipes. Inside the phase change heat exchanger, the heat released during the condensation of the condensation part is transferred to the evaporation part. After the evaporator 410 and the condenser 370 are combined into one component, the heat transfer is completed inside the phase change heat exchanger, which can reduce the loss during the heat transfer and further improve the energy utilization rate. It should be noted that heat transfer can be achieved in the above manner only when energy storage and energy release are performed at the same time. If they cannot operate at the same time, the energy needs to be stored first and then supplied to the evaporator 410 when it is evaporated.

As mentioned above, during the energy release process, the carbon dioxide from the third expander 443 flows into the energy release cooler 450 through the energy release eleventh pipe 4611, and the energy release cooler 450 cools it down so that its temperature can reach Gas storage 100 requirements. When the exothermic cooler 450 performs cooling and heat exchange, heat is released. Preferably, in some embodiments, this part of the heat can be recycled and used for carbon dioxide evaporation, so as to reduce energy waste and improve energy utilization.

Preferably, both the heat released during the condensation of carbon dioxide and the heat released by the energy releasing cooler 450 may be supplied to the evaporator 410 for use.

Specifically, both the energy releasing cooler 450 and the condenser 370 can be connected to the evaporator 410, and the heat released by the energy releasing cooler 450 during cooling and heat exchange and the heat released by the condenser 370 during condensation are all transferred to the evaporator 410. , for use when carbon dioxide evaporates. The energy releasing cooler 450 and the evaporator 410 may be directly connected or indirectly connected through other components. The condenser 370 and the evaporator 410 may be directly connected or indirectly connected through other components. When connected directly, there is only a recovery pipeline between them, and when connected indirectly, an intermediate storage part is also included.

For example, the intermediate storage member is a water pool 710 , and heat transfer between the energy-releasing cooler 450 and the evaporator 410 is achieved through the water pool 710 . A first recovery pipeline 720 and a second recovery pipeline 730 are provided between the water pool 710 and the energy releasing cooler 450 . A third recovery pipe 740 and a fourth recovery pipe 750 are provided between the water pool 710 and the evaporator 410 . A fifth recovery pipeline 760 and a sixth recovery pipeline 770 are provided between the water pool 710 and the condenser 370 . The pool 710 and each of the above-mentioned pipes are provided with thermal insulation materials to keep the water therein thermally insulated.

Open the fifth valve 650 and the sixth valve 660, a part of the water in the pool 710 flows to the condenser 370 through the fifth recovery pipe 760, absorbs the heat released by the condenser 370, and after the water temperature rises, passes through the sixth recovery pipe 770 flows into the pool. At the same time, a part of the water in the pool 710 flows to the energy releasing cooler 450 through the first recovery pipe 720 to absorb the heat released by the energy releasing cooler 450. After the water temperature rises, it flows to the pool 710 through the second recovery pipe 730. Inside.

When evaporating, the seventh valve 670 is opened, and the water with a higher temperature in the pool 710 flows to the evaporator 410 through the third recovery pipe 740 to provide heat for the evaporation of carbon dioxide. After flowing through the evaporator 410, the water temperature decreases, cooling down The latter water flows into the pool through the fourth recovery pipe 750 .

In the above process, in addition to the use of water for heat harvesting, other substances can also be used.

In addition, components such as a circulating pump are also provided on the first recovery pipeline 720, the second recovery pipeline 730, the third recovery pipeline 740, the fourth recovery pipeline 750, the fifth recovery pipeline 760 and the sixth recovery pipeline 770 to realize Circulation of water in the pool 710 .

When the heat released by the exothermic cooler 450 and the condenser 370 is continuously transferred to the water pool 710 , the water temperature in the water pool 710 may be continuously increased or even evaporated. When the evaporator 410 continuously absorbs the heat in the water pool 710, the water temperature in the water pool 710 may be continuously lowered or even frozen. Therefore, preferably, the pool 710 is in a constant temperature state.

Specifically, the pool is also connected with components such as a thermostatic controller, a temperature sensor, a heater and a radiator. The water temperature in the pool is monitored by the temperature sensor, and the water temperature is transmitted to the thermostatic controller. If the heat released by the energy releasing cooler 450 and the condenser 370 increases the water temperature too much and exceeds the maximum set value, the thermostatic controller controls The radiator dissipates heat from the pool. If the heat absorbed by the evaporator 410 reduces the water temperature too much and is lower than the minimum set value, the thermostat controller controls the heater to heat the pool.

In some embodiments, the heat released by the condenser 370, the heat released by the exothermic cooler 450, and the heat released by the heat exchange medium cooler 530 may all be supplied to the evaporator 410 for use. The specific setting method is similar to that of the above-mentioned embodiment, and details are not repeated here. In fact, the heat of the above three places can be supplied individually, or any two of them can be supplied together.

Preferably, multiple sets of the above-mentioned energy storage components 300 , energy release components 400 and heat exchange components 500 may be arranged between the gas storage 100 and the liquid storage tank 200 , each set is arranged in the manner in the foregoing embodiment. During use, if a component in one group fails, there are other groups that can work, which can reduce the failure downtime rate of the device and improve its working reliability.

In addition, in some embodiments, an energy storage method based on the gas-liquid phase transition of CO ₂ for supplementing external energy is also provided. During energy storage, carbon dioxide changes from gas to liquid state, and energy storage is completed during the energy storage process. When releasing energy, carbon dioxide changes from liquid state to gaseous state, and the energy release process completes the release of energy. When releasing energy, the energy is supplemented by an external heat source, so that there is enough energy to do external work when releasing energy.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

The above-mentioned embodiments only represent several embodiments of the present invention, and the descriptions thereof are more specific and detailed, but should not be construed as a limitation on the scope of the invention patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims (13)

1. An energy storage device based on _CO2 gas-liquid phase transition for supplementing external energy, characterized in that it includes:

   a gas storage, the gas storage is used for storing gaseous carbon dioxide, and the volume of the gas storage can be changed;

   a liquid storage tank, the liquid storage tank is used for storing liquid carbon dioxide;

   an energy storage assembly, the energy storage assembly is used to store energy, the energy storage assembly is arranged between the gas storage and the liquid storage tank, and carbon dioxide is converted from a gaseous state to a liquid state through the energy storage assembly;

   An energy release assembly, the energy release assembly is arranged between the gas storage and the liquid storage tank, the energy release component includes a plurality of expansion energy release parts, and the expansion energy release part includes an energy release heat exchanger , Supplementary energy heat exchanger and expander, the supplementary energy heat exchanger is provided between the energy release heat exchanger and the expander in each of the expansion energy release parts, and the expander uses For releasing energy, carbon dioxide is transformed from liquid to gaseous state through the energy releasing component;

   a heat exchange assembly, the energy storage assembly and the energy release assembly are both connected to the heat exchange assembly, and the heat exchange assembly can transfer part of the energy generated in the energy storage assembly to the energy release assembly;

   An energy supplement component, the energy supplement component includes an external heat source, a plurality of the supplementary energy heat exchangers are all connected to the external heat source, and the external heat source supplements energy to the expander through the supplementary energy heat exchanger.
2. The energy storage device based on supplementing external energy for CO ₂ gas-liquid phase transition according to claim 1, wherein the energy supplement component further comprises an inflow pipeline and an outflow pipeline, the inflow pipeline and the An energy supplementary medium is arranged in the outflow pipeline, a plurality of the supplementary energy heat exchangers are connected to the external heat source through the inflow pipeline, and the energy supplementary medium flows from the external heat source through the inflow pipeline To the supplementary energy heat exchanger, a plurality of the supplementary energy heat exchangers are connected to the external heat source through the outflow line, and the energy supplementary medium exchanges heat from the supplementary energy through the outflow line to the external heat source.
3. The energy storage device based on supplementing external energy for gas-liquid phase transition of CO ₂ according to claim 1, wherein a plurality of the expanders are arranged coaxially.
4. The energy storage device based on supplementing external energy for gas-liquid phase transition of CO ₂ according to claim 1, wherein the energy release component further comprises an evaporator and an energy release cooler, and the carbon dioxide is converted from liquid to liquid through the evaporator. Converted to a gaseous state, the energy release cooler is used to cool the carbon dioxide entering the gas storage, the energy release heat exchanger in the expansion energy release part at the beginning is connected to the evaporator, and the energy release heat exchanger at the end is connected to the evaporator. The expander in the expansion energy release part is connected with the energy release cooler, the expander in each expansion energy release part and the energy release in the adjacent expansion energy release part heat exchanger connection.
5. The energy storage device based on the gas-liquid phase transition of CO ₂ based on supplementary external energy according to claim 4, wherein the energy releasing cooler is connected to the evaporator.
6. The energy storage device based on CO ₂ gas-liquid phase transition for supplementing external energy according to claim 1, wherein the energy release component further comprises an evaporator, and the external heat source is connected to the evaporator.
7. The energy storage device based on the gas-liquid phase transition of CO ₂ supplemented with external energy according to claim 1, wherein the heat exchange component comprises a cold storage tank and a heat storage tank, the cold storage tank and the storage tank A heat exchange medium is arranged in the heat tank, the cold storage tank and the heat storage tank form a heat exchange circuit between the energy storage component and the energy release component, and the heat exchange medium can When the heat exchange medium flows from the cold storage tank to the heat storage tank, part of the energy generated by the energy storage assembly can be stored, and the heat exchange medium flows from the heat storage tank to the heat storage tank. When the cold storage tank is installed, the stored energy can be transferred to the energy releasing component.
8. The energy storage device based on CO ₂ gas-liquid phase change based on supplementary external energy according to claim 7, wherein an auxiliary heating element is arranged between the cold storage tank and the heat storage tank, and part of the exchange The heat medium can flow into the heat storage tank after being heated by the auxiliary heating element.
9. The energy storage device for gas-liquid phase transition of CO ₂ based on supplementary external energy according to claim 7, wherein the energy release component comprises an evaporator, and carbon dioxide is converted from liquid to gas through the evaporator, and the The heat exchange assembly further includes a heat exchange medium cooler, which is used for cooling the heat exchange medium entering the cold storage tank, and the heat exchange medium cooler is connected with the evaporator.
10. The energy storage device based on CO ₂ gas-liquid phase change based on supplementary external energy according to claim 1, wherein the energy storage component comprises a condenser and a compression energy storage part, and the compression energy storage part is provided with at least one The compression energy storage unit includes a compressor and an energy storage heat exchanger, the energy storage heat exchanger in each compression energy storage unit is connected to the compressor, and each compression energy storage unit is connected to the compressor. The energy storage heat exchanger in is connected with the compressor in the adjacent compression energy storage part, the compressor in the compression energy storage part at the beginning end is connected with the gas storage, and the end The energy storage heat exchanger in the compression energy storage part is connected with the condenser, the liquid storage tank is connected with the condenser, and the heat exchange component is connected with the energy storage heat exchanger, The energy storage heat exchanger can transfer part of the energy generated when the carbon dioxide is compressed by the compressor to the heat exchange component.
11. The energy storage device for gas-liquid phase transition of CO ₂ based on supplementary external energy according to claim 1, wherein the energy release component comprises a throttle expansion valve and an evaporator, and carbon dioxide is transformed from a liquid state through the evaporator In the gaseous state, the throttle expansion valve is located between the liquid storage tank and the evaporator, and the throttle expansion valve is used to depressurize the carbon dioxide flowing out of the liquid storage tank;

    The energy storage assembly includes a condenser through which carbon dioxide is converted from gaseous state to liquid state, and the evaporator is connected with the condenser.
12. The energy storage device based on the gas-liquid phase transition of CO ₂ supplemented with external energy according to claim 1, wherein the gas storage is a flexible gas film gas storage.
13. The energy storage method based on the gas-liquid phase transition of CO ₂ supplemented with external energy is characterized in that, it includes an energy storage step and an energy release step,

    In the energy storage step, carbon dioxide is changed from gaseous state to liquid state, and part of the energy is stored in the heat exchange medium;

    In the energy releasing step, carbon dioxide changes from liquid state to gaseous state, the energy stored in the heat exchange medium is released through carbon dioxide, and when energy is released, energy is supplemented by an external heat source.

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