CN210977616U - A supercritical compressed air energy storage system - Google Patents

Abstract

The utility model discloses a supercritical compressed air energy storage system, including energy storage section, cold-storage liquefaction section and inflation section. And the multi-stage compressor, the intercooler and the aftercooler in the energy storage section are sequentially connected. The cold accumulation heat exchanger, the liquid expander, the liquid air storage tank, the three-way conversion valve, the cryogenic pump and the cold energy heat exchanger in the cold accumulation liquefaction section are sequentially connected. The reheater and the expander in the expansion section are connected in sequence. The utility model discloses a supercritical compressed air energy storage system has energy density height, efficient, can provide different grade cold volume and merit volume, load and follow good advantage, is applicable to fields such as electric wire netting peak shaving, renewable energy, distributed energy, and is friendly to the environment.

Description

A supercritical compressed air energy storage system

technical field

The utility model belongs to the fields of compressed air energy storage, low-temperature refrigeration, renewable energy, distributed energy and the like, relates to a compressed air energy storage system, in particular to a supercritical compressed air storage system utilizing liquid air for energy storage and cold storage It is a supercritical compressed air energy storage system that can realize the cascade utilization of work and cold energy.

Background technique

The sustainable development of energy and environmental problems is the foundation of national economic development, and solving the energy and environmental problems in the power industry is an important part of ensuring the sustainable development of my country's economy. Electric energy storage is one of the key technologies for adjusting my country's energy structure, developing renewable energy on a large scale, and improving energy security. The research on large-scale energy storage technology has important theoretical and practical value.

The current energy storage systems include pumped storage, compressed air storage, and fuel cells. Pumped storage and compressed air storage have the characteristics of high energy storage density and high output power. However, pumped storage power stations must build dams, which consume a lot of water and cause certain damage to the ecology. The compressed air energy storage system does not consume water and has no impact on the ecological environment. It has the advantages of low initial investment cost, high efficiency, non-toxicity, and long life, and has great development prospects.

The traditional compressed air energy storage power station stores high-pressure air in the gas storage chamber. When releasing energy, the inlet temperature of the expander needs to be increased by burning the high-pressure air and fuel. The energy density is low, which is limited by geographical location, and at the same time, it relies on chemical fuel to provide heat source. . The supercritical compressed air energy storage system combines the regenerative compressed air energy storage system with the liquid air energy storage system. The system does not require a combustion chamber, and the air is stored in the storage tank in liquid form, which is not restricted by the geographical environment and has a high energy density. However, the current supercritical compressed air energy storage system has problems such as large cold storage loss and insufficient energy utilization. In addition, the current supercritical compressed air energy storage system only provides work, and the energy output method is relatively simple.

Utility model content

Aiming at the above-mentioned defects and deficiencies of the prior art, the present utility model aims to provide a supercritical compressed air energy storage system that utilizes liquid air for power storage and cold storage. It is a supercritical compressed air energy storage system that realizes the cascade utilization of work and cooling energy.

The technical scheme adopted by the present utility model for realizing its technical purpose is:

A supercritical compressed air energy storage system, comprising a multistage compressor, an intercooler, an aftercooler, a multistage cold storage heat exchanger, a liquid expander, a liquid air storage tank, a reheater, a multistage expander, a normal temperature Water tank, hot water tank, characterized in that:

In the multi-stage compressor, the gas pipelines of the compressors of each stage are connected in sequence, an air cooler is arranged on the exhaust pipeline of each stage compressor, the air inlet of the first stage compressor is communicated with the atmosphere, and the last stage compressor is connected to the atmosphere. The exhaust port of the first-stage compressor is connected to the inlet of the liquid air storage tank through the pipeline through a cooler, an after-cooler, the hot side of the cold storage heat exchangers at all levels, and the liquid expander.

In the multi-stage expander, the gas pipelines of the expanders of each stage are connected in sequence, a reheater is arranged on the intake line of each stage of the expander, and the exhaust port of the last stage of the expander is communicated with the atmosphere, and the liquid The liquid air outlet of the air storage tank is communicated with the air inlet of the first-stage expander through the pipeline through the first cold side of the cold-storage heat exchangers of all levels in turn,

The hot side of each intercooler is correspondingly arranged on the exhaust line of the compressors of all levels, the cold side inlet of each intercooler is connected with the outlet of the normal temperature water tank through the pipeline, and the cold side of each intercooler is connected with the outlet of the normal temperature water tank respectively. The outlets are respectively communicated with the inlet of the hot water tank through pipelines,

The cold side of each reheater is correspondingly arranged on the intake pipeline of the expanders at all levels, the hot side inlet of each reheater is respectively connected with the outlet of the hot water tank through the pipeline, and the hot side of each reheater is respectively connected with the outlet of the hot water tank. The outlets are respectively communicated with the inlets of the normal temperature water tank through pipelines.

Preferably, the uncondensed low-temperature atmospheric air outlet of the liquid air storage tank is communicated with the atmosphere after passing through the second cold side of the cold storage heat exchangers of all stages in sequence through pipelines.

Further, the uncondensed low-temperature atmospheric air outlet is arranged at the top of the liquid air storage tank, and the liquid air outlet of the liquid air storage tank is arranged at the bottom.

Preferably, a radiator is provided on the inlet pipeline of the normal temperature water tank.

Preferably, a cryogenic pump and a cooling heat exchanger are provided on the liquid air outlet pipeline of the liquid air storage tank, and a three-way switching valve is respectively provided at the inlet of the cryogenic pump and the cooling heat exchanger, A bypass pipeline is arranged between the three-way switching valve and the corresponding outlet respectively. When the system releases energy/cooling, the liquid air discharged from the liquid air storage tank is pressurized to a certain pressure by the cryogenic pump, and then can be transported to the low-temperature cooling heat exchanger to realize the transportation of cold energy and the gas transportation after heat exchange. It is heated in the cold storage heat exchangers at all levels, and the cold energy is recovered at the same time. The three-way switching valve is selectively opened or closed to meet the cold energy distribution of different users and the pressurization requirements of different energy release pressures.

Further, the outlet pipelines of the first cold side of the cold storage heat exchangers at all levels are also provided with cryopumps and refrigerating heat exchangers respectively, and three-way switching valves are respectively provided at the inlets of each cryopump and refrigerating heat exchangers. , and a bypass pipeline is set between the three-way switching valve and the outlet of the corresponding component respectively. Among them, the cryopump increases the air pressure energy by pressurizing, and realizes the expansion of the air in the expander to do work, and the cold heat exchanger realizes the flexible release of cold energy by exchanging heat with the outside world. The cryopump and the cold heat exchanger are selectively opened or closed through a three-way switching valve, so as to satisfy the distribution of cold energy required by different users.

Further, the outlet pipeline of the first cold side of the downstream at least one-stage cold storage heat exchanger is respectively provided with a cryopump and a cold heat exchanger, and the inlets of the cryopump and the cold heat exchanger are respectively provided with a three-way switch. A bypass pipeline is set between the three-way switching valve and the outlet of the corresponding component; the outlet pipelines of the first cold side of the other cold storage heat exchangers at all levels are respectively provided with only one cooling heat exchanger, and each A three-way switching valve is respectively provided at the inlet of a cooling heat exchanger, and a bypass pipeline is respectively set between the three-way switching valve and the outlet of the corresponding component. Among them, the cryopump increases the air pressure energy by pressurizing, and realizes the expansion of the air in the expander to do work, and the cold heat exchanger realizes the flexible release of cold energy by exchanging heat with the outside world. The cryopump and the cold heat exchanger are selectively opened or closed through a three-way switching valve, so as to satisfy the distribution of cold energy required by different users.

Preferably, a cryopump is respectively provided on the liquid air outlet line of the liquid air storage tank and the outlet line of the first cold side of the cold storage heat exchangers of all levels, and a first and third cryopumps are respectively provided at the inlet of each cryopump. There is a second three-way switching valve at the pass switching valve and the outlet, and a bypass pipeline is set between the first three-way switching valve and the corresponding outlet, and the inlet of the second three-way switching valve is connected with the outlet of the cryogenic pump. The first outlet communicates with the inlet of the first cold side of the cold storage heat exchanger immediately downstream, and a cold heat exchanger is arranged on the second outlet pipeline, and the outlet of the cold heat exchanger communicates with the outside. Among them, the cryopump increases the air pressure energy by pressurizing, and realizes the expansion of the air in the expander to do work, and the cold heat exchanger realizes the flexible release of cold energy by exchanging heat with the outside world. The cryopump and the cold heat exchanger are selectively opened or closed through a three-way switching valve, so as to satisfy the distribution of cold energy required by different users.

Preferably, a cryopump is respectively provided on the liquid air outlet line of the liquid air storage tank and the outlet line of the first cold side of the downstream at least one stage cold storage heat exchanger, and a cryopump is respectively provided at the inlet of each cryopump The first three-way switching valve and the outlet are respectively provided with a second three-way switching valve, and a bypass pipeline is set between the first three-way switching valve and the corresponding outlet respectively, and the inlet of the second three-way switching valve is connected to the low temperature The outlet of the pump is communicated, the first outlet is communicated with the inlet of the first cold side of the cold storage heat exchanger immediately downstream, a cold heat exchanger is arranged on the second outlet pipeline, and the outlet of the cold heat exchanger is communicated with the outside; A third three-way switching valve is respectively provided on the outlet pipeline of the first cold side of the other cold storage heat exchangers at all levels, and the first outlet of the third three-way switching valve is connected to the first cold side of the cold storage heat exchanger immediately downstream. The inlet is communicated with, and a cooling heat exchanger is arranged on the second outlet pipeline, and the outlet of the cooling heat exchanger is communicated with the outside. Among them, the cryopump increases the air pressure energy by pressurizing, and realizes the expansion of the air in the expander to do work, and the cold heat exchanger realizes the flexible release of cold energy by exchanging heat with the outside world. The cryopump and the cold heat exchanger are selectively opened or closed through a three-way switching valve, so as to satisfy the distribution of cold energy required by different users.

The above-mentioned supercritical compressed air energy storage system of the present invention can be divided into an energy storage section, a cold storage liquefaction section and an energy release section according to the combined functions of the components:

In the energy storage section, the multi-stage compressors, the intercoolers at all levels, and the aftercoolers are connected in sequence.

In the energy release section, the reheaters at all levels and the multi-stage expanders are connected in sequence. The hot water side of the reheater is connected to the hot water tank, the cold water side of the intercooler and the normal temperature water tank in sequence through pipes.

In the cold storage liquefaction section, the cold storage heat exchangers at all levels, the liquid expander, the liquid air storage tank, the three-way switching valve, the cryogenic pump, and the cooling heat exchanger are connected in sequence. The top gas side of the liquid air storage tank and the cold storage heat exchanger are connected in sequence through pipelines. The cryopump increases the air pressure energy through pressurization, and realizes the expansion work of the air in the expander. The cold heat exchanger realizes flexible release of cold energy by exchanging heat with the outside world.

In the supercritical compressed air energy storage system of the utility model, the liquid air in the liquid air storage tank flows through the cryogenic pump and the cold heat exchanger to absorb heat and provide cold energy. In the cold storage heat exchangers at all levels, the high-pressure air after pressurization and heat exchange enters the multi-stage expander through the reheaters at all levels to perform expansion and work, so as to realize the cascade utilization of work.

In the supercritical compressed air energy storage system of the utility model, after the high-pressure air is cooled by the aftercooler and the cold storage heat exchangers at all levels, it is expanded and liquefied by the liquid expander and then enters the liquid air storage tank for storage.

Preferably, the cold storage heat exchangers at all levels can be in the form of packed bed direct cold storage, packed bed indirect cold storage, and double-tank indirect cold storage using liquid cold storage working medium.

Preferably, a water pump is provided on the outlet pipelines of the normal temperature water tank and the hot water tank.

Preferably, the cold heat exchanger, reheater and intercooler are one or more combinations of plate-fin type, shell-and-tube type, and plate-type heat exchangers.

Preferably, the multi-stage compressor is driven by an electric motor, and the multi-stage expander is drivingly connected to a generator.

Preferably, the multi-stage compressor and the multi-stage expander are one of a piston type, an axial flow type, a centrifugal type, a screw type or a hybrid impeller.

The supercritical compressed air energy storage system of the utility model has the following working principles:

When storing energy, the multi-stage compressor is driven by excess electric energy to compress the air to a supercritical state. After cooling through the intercoolers and after-coolers at all levels, the supercritical air is compressed by the cold energy stored in the multi-stage cold storage heat exchanger. The air in the state is isobarically cooled again, and then expanded and liquefied by the liquid expander and stored in the liquid air storage tank. At the same time, the compression heat generated by the air in the multi-stage compression process is recovered and stored in the hot water tank.

When releasing energy, the liquid air is pressurized to supercritical pressure by a cryogenic pump, heated to normal temperature in a cold storage heat exchanger and a cold heat exchanger, and then expanded by a multi-stage expander to do work after absorbing the heat of compression in the reheater. . At the same time, part of the cold energy in the liquid air is recovered and stored in the cold storage heat exchanger, and a part is used for the provision of cold energy through the cold heat exchanger.

In the supercritical compressed air energy storage system of the present invention, the cryogenic pump increases the air pressure energy through pressurization, so as to realize the expansion work of the air in the expander. The cold heat exchanger realizes flexible release of cold energy by exchanging heat with the outside world. The high-pressure air after pressurization and heat exchange in the cold storage and liquefaction section enters the multi-stage expansion unit through the reheater to perform expansion and work, so as to realize the cascade utilization of work. In the cold storage and liquefaction section, one-stage or multi-stage cryogenic pumps and multi-stage cold heat exchangers are used for pressurized heat exchange, thereby realizing the cascade utilization of cold energy. The cryopump and the cold heat exchanger can be selectively opened or closed through a valve, so as to satisfy the distribution of cold energy required by different users.

It can be seen from the above technical solutions that, compared with the prior art, the beneficial effect of the present utility model is that the system combines low-temperature refrigeration and gas expansion work on the basis of the supercritical compressed air energy storage system, and utilizes multi-stage cold storage. The heat exchanger, cryogenic pump and multi-stage cooling heat exchanger realize the cascade utilization of work and cold energy, and improve the energy utilization efficiency of the system. The supercritical compressed air energy storage system of the utility model has the advantages of high energy density and high efficiency, and can provide the advantages of different grades of cooling capacity, power capacity, and good load following, and is suitable for the fields of power grid peak regulation, renewable energy, distributed energy and the like , which is environmentally friendly.

Description of drawings

Fig. 1 is the supercritical compressed air energy storage system schematic diagram of the present invention;

2 is a schematic structural diagram of the cold storage liquefaction section in the supercritical compressed air energy storage system (closed type) of the present invention.

3 is a schematic structural diagram of the cold storage liquefaction section in the supercritical compressed air energy storage system (open type) of the present invention.

Description of the serial number in the figure:

1: Atmosphere; 2: Aftercooler; 3: Inlet of cold storage liquefaction section; 4: Inlet of liquid expander; 5: Liquid expander; 6: Liquid air outlet of liquid expander; 7: Liquid air storage tank; 8: Liquid Liquid air outlet of the air storage tank; 9: Low temperature and atmospheric air; 10: Atmospheric air outlet; 11: High pressure air for entering the expansion section; 12: Exhaust from the final stage expander; 13: Normal temperature water tank; 14: Hot water tank; 15: radiator; 16: water pump; 17: water pump; 18: electric motor; 19: generator; V1~V9: three-way switching valve; C1~C4: compressor; A1~A4: intercooler; B, B1~B5: cold storage heat exchanger; P, P1~P3: cryogenic pump; H1~H6: cooling heat exchanger; E1~E4: expander; R1~R4: reheater

Detailed ways

In order to make the purpose, technical solutions and advantages of the present utility model more clearly understood, the present utility model will be further described in detail below with reference to the accompanying drawings and examples.

As shown in Figure 1, the supercritical compressed air energy storage system of the present invention includes multi-stage compressors C1-C4, intercoolers A1-A4, aftercooler 2, multi-stage cold storage heat exchanger B, and liquid expander 5. Liquid air storage tank 7, cryogenic pump P1, cooling heat exchanger H1, reheaters R1-R4, multi-stage expanders E1-E4, radiator 15, normal temperature water tank 13, hot water tank 14. Among them, in the multi-stage compressors C1-C4, the gas pipelines of the compressors C1-C4 of each stage are connected in sequence, and a cooler A1-A4 is arranged on the exhaust pipelines of the compressors C1-C4 of each stage. The air inlet of the compressor C1 is communicated with the atmosphere 1, and the exhaust port of the last stage compressor C4 passes through a cooler A4 and an aftercooler 2 in turn through the pipeline and then leads to the hot side of the multi-stage cold storage heat exchanger B. The inlet (ie, the inlet 3 of the cold storage and liquefaction section), the hot side outlet of the multi-stage cold storage heat exchanger B is communicated with the inlet 4 of the liquid expander 5, and the liquid air outlet 6 of the liquid expander 5 is communicated with the inlet of the liquid air storage tank 7. In the multi-stage expanders E1-E4, the gas pipelines of the expanders E1-E4 of each stage are connected in sequence, and a reheater R1-R4 is arranged on the intake pipeline of each stage expander E1-E4, and the gas pipelines of the last-stage expander E4 are provided with a reheater R1-R4. The exhaust gas 12 is communicated with the atmosphere, and the liquid air outlet 8 of the liquid air storage tank 7 is communicated with the air inlet of the first stage expander E1 after passing through the first cold side of the cold storage heat exchangers B of all stages in sequence through pipelines. The hot side of each intercooler A1-A4 is respectively arranged on the exhaust pipeline of each stage compressor C1-C4, and the cold side inlet of each intercooler A1-A4 is communicated with the outlet of the normal temperature water tank 13 through the pipeline respectively. , the cold-side outlets of each intercooler A1-A4 are respectively connected with the inlet of the hot water tank 14 through pipelines, and the cold-side outlets of each reheater R1-R4 are respectively arranged in the intake lines of the expanders E1-E4 at all levels On the other hand, the hot-side inlets of the reheaters R1 to R4 are respectively connected to the outlet of the hot water tank 14 through pipelines, and the hot-side outlets of the reheaters R1 to R4 are respectively connected to the inlet of the normal temperature water tank 13 through pipelines.

And further, continue to refer to FIG. 1, the uncondensed low-temperature atmospheric air outlet of the liquid air storage tank 7 passes through the pipeline of the low-temperature atmospheric air 9 in turn through the second cold side of the cold storage heat exchanger B at all levels, and then passes through the atmospheric air outlet. 10 is in communication with the atmosphere. The uncondensed low-temperature atmospheric air outlet of the liquid air storage tank 7 is arranged at the top of the liquid air storage tank 7, and the liquid air outlet of the liquid air storage tank 7 is arranged at the bottom. A radiator 15 is provided on the inlet pipeline of the normal temperature water tank 13 , and water pumps 16 and 17 are provided on the outlet pipelines of the normal temperature water tank 13 and the hot water tank 14 . The drive unit 18 is coaxially connected to the multi-stage compressors C1-C4, and the generator 19 is coaxially connected to the expanders E1-E4.

Continue to refer to Fig. 1, as a kind of preference, the liquid air outlet pipeline of the liquid air storage tank 7 is provided with a cryopump P1 and a cooling heat exchanger H1, and the inlets of the cryopump P1 and the cooling heat exchanger H1 are respectively A three-way switching valve V1 is provided, and a bypass pipeline is respectively arranged between the three-way switching valve V1 and the corresponding outlet. When the system releases energy/cooling, the liquid air discharged from the liquid air storage tank 7 is pressurized to a certain pressure by the cryogenic pump P1, and can be transported to the low-temperature cooling heat exchanger H1 to realize the transmission of cold energy, and the gas after heat exchange It is transported to the cold storage heat exchanger B at all levels for heating, and the cold energy is recovered at the same time.

Among them, the cryopump increases the air pressure energy by pressurizing, and realizes the expansion of the air in the expander to do work, and the cold heat exchanger realizes the flexible release of cold energy by exchanging heat with the outside world. The cryogenic pump and the cooling heat exchanger are selectively opened or closed through the three-way switching valve, so as to meet the cold energy distribution of different user needs.

As a preference, FIG. 2 is a schematic structural diagram of the cold storage liquefaction section in the supercritical compressed air energy storage system (closed type) of the present invention. Referring to Figures 1 and 2 at the same time, the exhaust port of the last stage compressor C4 passes through the intercooler A4 and the aftercooler 2 in sequence through the pipeline and then leads to the hot side inlets of the multi-stage cold storage heat exchangers B1 to B5 (that is, the cold storage liquefaction Section inlet 3), the hot-side outlets of the multi-stage cold storage heat exchangers B1-B5 communicate with the inlet 4 of the liquid expander 5, and the liquid air outlet 6 of the liquid expander 5 communicates with the inlet of the liquid air storage tank 7. The uncondensed low-temperature atmospheric air outlet of the liquid air storage tank 7 is communicated with the atmosphere through the atmospheric air outlet 10 through the pipeline of the low-temperature atmospheric air 9 sequentially through the second cold side of the cold storage heat exchangers B1-B5 of all stages. The liquid air outlet 8 of the liquid air storage tank 7 is communicated with the air inlet of the first stage expander E1 after passing through the first cold side of the cold storage heat exchangers B1 to B5 of each stage in sequence through pipelines.

A cryopump P1 and a cooling heat exchanger H1 are provided on the liquid air outlet pipeline of the liquid air storage tank 7, and a three-way switching valve V1 and V2 are respectively provided at the inlets of the cryopump P1 and the cooling heat exchanger H1. , and set up a bypass pipeline between the three-way switching valves V1, V2 and the corresponding outlet respectively. When the system releases energy/cooling, the liquid air discharged from the liquid air storage tank 7 is pressurized to a certain pressure by the cryogenic pump P1, and can be transported to the low-temperature cooling heat exchanger H1 to realize the transmission of cold energy, and the gas after heat exchange It is transported to the cold storage heat exchanger B at all levels for heating, and the cold energy is recovered at the same time.

The outlet pipelines of the first cold side of the 4th and 5th stage cold storage heat exchangers B4 and B5 are respectively provided with cryopumps P2 and P3 and cold heat exchangers H2 and H3, and cryopumps P2 and P3 and cold heat exchange There are three-way switching valves V3~V6 at the inlets of the H2 and H3 respectively, and bypass pipelines are set between the three-way switching valves V3~V6 and the outlets of the corresponding components respectively; the other stages of the cold storage heat exchangers B1~B3 The outlet pipeline of the first cold side is only provided with cooling heat exchangers H4~H6, and the inlets of each cooling heat exchanger H4~H6 are respectively provided with three-way switching valves V7~V9, and through the three-way switching valve V7~V9 A bypass line is provided between the switching valves V7 to V9 and the outlet of the corresponding component, respectively. Among them, the cryopumps P2 and P3 increase the air pressure energy by pressurizing, and realize the expansion work of the air in the expanders E1-E4, and the cold heat exchangers H1-H6 realize the flexible release of cold energy by exchanging heat with the outside world. The cryogenic pumps P2, P3 and the cooling heat exchangers H1~H6 are selectively opened or closed through the three-way switching valve, so as to meet the cold energy distribution of different user needs.

1 and 2, when the supercritical compressed air energy storage system of the present invention is storing energy/cooling, the drive unit 18 drives the compressors C1 to C4 to compress the air to the supercritical state step by step, and the intercoolers A1 to A4 Stores the heat of compression and achieves interstage cooling of the air. The air in the critical state is cooled and liquefied by isobaric cooling in the multi-stage cold storage heat exchangers B1-B5, expanded by the liquid expander 5 to do work, cooled and depressurized, liquefied, and stored in the liquid air storage tank 7.

When releasing energy/cooling, the liquid air is pressurized to a certain pressure by the cryogenic pump P1, and can be transported to the low-temperature cooling heat exchanger H1 to realize the transportation of cold energy, and the gas after heat exchange is transported to the cold storage heat exchanger B5 Heating, at the same time recovering cold energy, the cold storage heat exchanger B5 is pressurized by the cryopump P2 again (this step is when the air is liquid and the energy release pressure is insufficient, if it is not any of the above two situations, do not carry out After this step) and the low-temperature heat exchanger H2 release cooling (if the gradient cooling energy is required, do not perform this step) and then enter the cold storage heat exchanger B4, and so on until the last stage of the cold storage heat exchanger B1, is The gas heated by the cold storage heat exchanger B1 absorbs the heat of compression in the reheaters R1-R4 to further heat up, and the heated high-temperature and high-pressure gas enters the multi-stage expanders E1-E4 through the pipeline to expand and do work. Reheaters R1 to R4 are used for interstage heating of air. The number of cryogenic heat exchangers and cryogenic pumps in the system can be set according to user needs. In this implementation case, 3 cryogenic pumps and 6 cryogenic heat exchangers are selected.

In general, the energy storage/cooling storage and energy/cooling release processes do not run at the same time. During energy storage/cold storage, compressor units C1 to C4 and liquid expander 5 work, expansion units E1 to E4 and cryogenic pumps P1 to P3 are shut down, and intercoolers A1 to A4 recover compression heat, cool gas, and hot water tank 14 The heat of compression is stored, and the cold storage heat exchangers B1 to B5 release the cold energy to cool the gas. When releasing energy/cooling, the opposite is true. Compressor units C1 to C4 and liquid expander 5 are shut down, expansion units E1 to E4 and cryogenic pumps P1 to P3 work, and cold storage heat exchangers B1 to B5 recover the stored cooling capacity. Heaters R1 to R4 release the heat of compression to raise the air temperature.

As another preference, FIG. 3 is a schematic structural diagram of the cold storage liquefaction section in the supercritical compressed air energy storage system (open type) of the present invention. Its structure is basically the same as the example shown in Figure 2, but the air after the cold energy is released by the low temperature heat exchanger no longer returns to the cold storage heat exchanger, but is directly discharged, in order to obtain a larger temperature range for releasing cold energy. . Other workflows are similar.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of the utility model.

Claims (10)

1. A supercritical compressed air energy storage system, comprising a multistage compressor, an intercooler, an aftercooler, a multistage cold storage heat exchanger, a liquid expander, a liquid air storage tank, a reheater, and a multistage expander , room temperature water tank, hot water tank, it is characterized in that, In the multi-stage compressor, the gas pipelines of the compressors of each stage are connected in sequence, an air cooler is arranged on the exhaust pipeline of each stage compressor, the air inlet of the first stage compressor is communicated with the atmosphere, and the last stage compressor is connected to the atmosphere. The exhaust port of the first-stage compressor is connected to the inlet of the liquid air storage tank through the pipeline through a cooler, an after-cooler, the hot side of the cold storage heat exchangers at all levels, and the liquid expander. In the multi-stage expander, the gas pipelines of the expanders of each stage are connected in sequence, a reheater is arranged on the intake line of each stage of the expander, and the exhaust port of the last stage of the expander is communicated with the atmosphere, and the liquid The liquid air outlet of the air storage tank is communicated with the air inlet of the first-stage expander through the pipeline through the first cold side of the cold-storage heat exchangers of all levels in turn, The hot side of each intercooler is correspondingly arranged on the exhaust line of the compressors of all levels, the cold side inlet of each intercooler is connected with the outlet of the normal temperature water tank through the pipeline, and the cold side of each intercooler is connected with the outlet of the normal temperature water tank respectively. The outlets are respectively communicated with the inlet of the hot water tank through pipelines, The cold side of each reheater is correspondingly arranged on the intake pipeline of the expanders at all levels, the hot side inlet of each reheater is respectively connected with the outlet of the hot water tank through the pipeline, and the hot side of each reheater is respectively connected with the outlet of the hot water tank. The outlets are respectively communicated with the inlets of the normal temperature water tank through pipelines. 2. The supercritical compressed air energy storage system according to claim 1, wherein the uncondensed low-temperature atmospheric air outlet of the liquid air storage tank passes through the second cold side of the cold storage heat exchangers of all levels successively through pipelines. communicated with the atmosphere. 3. supercritical compressed air energy storage system according to claim 2, is characterized in that, described uncondensed low temperature normal pressure air outlet is arranged on the top of liquid air storage tank, and the liquid air outlet of described liquid air storage tank is arranged at the bottom. 4 . The supercritical compressed air energy storage system according to claim 1 , wherein a radiator is arranged on the inlet pipeline of the normal temperature water tank. 5 . 5. The supercritical compressed air energy storage system according to claim 1, wherein the liquid air outlet pipeline of the liquid air storage tank is provided with a cryopump and a cooling heat exchanger, and the cryopump is A three-way switching valve is respectively provided at the inlet of the cooling heat exchanger, and a bypass pipeline is respectively set between the three-way switching valve and the corresponding outlet. 6. The supercritical compressed air energy storage system according to claim 5, wherein the outlet pipeline of the first cold side of the cold storage heat exchangers at all levels is also provided with a cryopump and a cold heat exchanger respectively, and each A three-way switching valve is respectively provided at the inlet of a cryogenic pump and a cooling heat exchanger, and a bypass pipeline is respectively arranged between the three-way switching valve and the outlet of the corresponding component. 7 . The supercritical compressed air energy storage system according to claim 5 , wherein the outlet pipeline of the first cold side of the downstream at least one stage cold storage heat exchanger is respectively provided with a cryopump and a cold heat exchanger. 8 . , and the inlets of the cryogenic pump and the cooling heat exchanger are respectively provided with three-way switching valves, and a bypass pipeline is set between the three-way switching valves and the outlets of the corresponding components; There is only one cooling heat exchanger on the outlet pipeline of the cold side, and a three-way switching valve is respectively set at the inlet of each cooling heat exchanger, and a side is set between the three-way switching valve and the outlet of the corresponding component. through the pipeline. 8. The supercritical compressed air energy storage system according to claim 1, wherein the liquid air outlet pipeline of the liquid air storage tank and the outlet pipeline of the first cold side of the cold storage heat exchangers of all levels are respectively provided with There is a cryogenic pump, and each cryopump is provided with a first three-way switching valve at the inlet, and a second three-way switching valve at the outlet, which is set between the first three-way switching valve and the corresponding outlet. A bypass pipeline, the inlet of the second three-way switching valve is communicated with the outlet of the cryopump, the first outlet is communicated with the inlet of the first cold side of the cold storage heat exchanger immediately downstream, and a cooling capacity exchanger is arranged on the second outlet pipeline Heater, and the outlet of the cold heat exchanger communicates with the outside world. 9 . The supercritical compressed air energy storage system according to claim 1 , wherein the liquid air outlet pipeline of the liquid air storage tank and the outlet pipeline of the first cold side of the downstream at least one stage cold storage heat exchanger There is a cryogenic pump respectively, and a first three-way switching valve is respectively set at the inlet of each cryopump, and a second three-way switching valve is respectively set at the outlet, and the first three-way switching valve is respectively connected with the corresponding outlet. A bypass pipeline is set between them, the inlet of the second three-way switching valve is communicated with the outlet of the cryopump, the first outlet is communicated with the inlet of the first cold side of the cold storage heat exchanger immediately downstream, and a second outlet pipeline is provided with a bypass. A cooling capacity heat exchanger, and the outlet of the cooling capacity heat exchanger is communicated with the outside world; a third three-way switching valve and a third three-way switching valve are respectively provided on the outlet pipelines of the first cold side of the remaining cold storage heat exchangers at all levels The first outlet is communicated with the inlet of the first cold side of the immediately downstream cold storage heat exchanger, a cold heat exchanger is arranged on the second outlet pipeline, and the outlet of the cold heat exchanger is communicated with the outside world. 10 . The supercritical compressed air energy storage system according to claim 1 , wherein a water pump is provided on the outlet pipelines of the normal temperature water tank and the hot water tank. 11 .

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