Liquid air energy storage system combined with vortex refrigeration

Abstract

The invention provides a liquid air energy storage system combined with vortex refrigeration, which comprises an air purification unit and a liquid air energy storage unit, and is characterized in that the liquid air energy storage unit comprises a compressor unit at a compression end; the air purification unit comprises an air compressor, a first vortex tube, an adsorption device and a desorption device, the outlet end of the air compressor is connected with the first vortex tube, and a cold end branch and a hot end branch of the first vortex tube are connected with an inlet of the adsorption device and an inlet of the desorption device respectively; the other cold end branch and the other hot end branch of the first vortex tube are connected with an inlet of the desorption device and an inlet of the adsorption device respectively, the outlet end of the desorption device and the outlet end of the adsorption device are connected to the inlet end of the compressor unit, and regulation and control valves are arranged on the two cold end branches and the two hot end branches of the first vortex tube. The desorption device can be heated and regenerated through heat energy generated by the vortex tube, meanwhile, the hot air flow can also purge foreign gas, and an external heat source is not needed.

Description

Technical Field

[0001] The present invention relates to the field of refrigeration and energy storage technology, and in particular to a liquid air energy storage system combined with eddy current refrigeration. Background Art

[0002] Liquid air energy storage technology is an important measure to solve the intermittent nature of renewable energy and improve the regulation and safety capabilities of power systems. Liquid air energy storage technology stores electrical energy in the form of liquid air during low energy consumption periods. During peak energy consumption periods, the liquid air reheats and vaporizes, expanding and performing work to release electrical energy, thereby regulating the power system.

[0003] Before the air is liquefied, it must first be purified to meet the purity requirements of the air at the front inlet of the liquid air energy storage system. Through purification, moisture and impurity gases such as carbon dioxide in the air are removed to avoid problems such as equipment blockage during subsequent low-temperature processes, thereby ensuring the safety of the equipment and the reliable operation of the liquid air energy storage system. Molecular sieve purification devices are usually used to remove impurity gases. When the device reaches or approaches the adsorption capacity, desorption operation is required. The molecular sieve purification device of the air purification unit of the liquid air energy storage system is usually two sets of equipment switched in operation. When one set is in the adsorption state, the other set is in the regeneration state. During the operation of the molecular sieve purification device, there are various energy losses. On the one hand, when the molecular sieve purification device adsorbs air, the air needs to overcome flow resistance and consume energy; on the other hand, during the regeneration process, the molecular sieve purification device needs to be heated to achieve desorption and regeneration of the purification device. The energy consumption during the air purification process will also affect the efficiency and cost of the liquid air energy storage system.

[0004] In view of this, the present invention provides a liquid air energy storage system combined with eddy current refrigeration, which can significantly improve the air adsorption purification efficiency while improving the energy storage efficiency of the entire system. Summary of the Invention

[0005] In order to solve the problem that energy consumption in the air purification process affects the low energy storage efficiency of the liquid air energy storage system, the present invention proposes a liquid air energy storage system combined with eddy current refrigeration.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention proposes a liquid air energy storage system combined with eddy current refrigeration, comprising an air purification unit and a liquid air energy storage unit, wherein:

[0008] The liquid air energy storage unit includes a compressor unit at the compression end;

[0009] The air purification unit includes an air compressor, a first vortex tube, an adsorption device and a desorption device, wherein the outlet end of the air compressor is connected to the first vortex tube, a cold end branch and a hot end branch of the first vortex tube are respectively connected to the inlet of the adsorption device and the inlet of the desorption device, another cold end branch and another hot end branch of the first vortex tube are respectively connected to the inlet of the desorption device and the inlet of the adsorption device, the outlet ends of the desorption device and the adsorption device are connected to the inlet end of the compressor unit, and regulating valves are provided on the two cold end branches and the two hot end branches of the first vortex tube.

[0010] Furthermore, the liquid air energy storage unit also includes a first heat exchanger, a second heat exchanger, a first storage tank and a second storage tank. One end of the first heat exchanger is connected to the first storage tank, the second heat exchanger and the second storage tank in sequence, and is connected to the other end of the first heat exchanger from the outlet of the second storage tank.

[0011] Furthermore, the liquid air energy storage unit also includes a second vortex tube, a cold storage device and a third storage tank. The outlet end of the compressor unit is connected to the first heat exchanger and the second vortex tube in sequence, and the cold end of the second vortex tube is connected to the cold storage device and the third storage tank in sequence.

[0012] Furthermore, the liquid air energy storage unit also includes a third heat exchanger, the hot end of the second vortex tube is connected to the third heat exchanger and the inlet end of the cold storage device in sequence, one outlet end of the second storage tank is connected to the third heat exchanger, and is connected from the outlet end of the third heat exchanger to the inlet end of the first storage tank.

[0013] Furthermore, the liquid air energy storage unit also includes a cooling device and an expansion unit, and the outlet end of the third storage tank is connected to the cooling device, the cooling device, the second heat exchanger and the expansion unit in sequence.

[0014] Furthermore, a pressure reducing device is provided between the cold storage device and the inlet end of the third storage tank.

[0015] Furthermore, a low-temperature pump is provided between the outlet end of the third storage tank and the cold storage device.

[0016] Beneficial effects of the present invention:

[0017] The liquid air energy storage system combined with vortex refrigeration proposed in the present invention flexibly couples vortex tube refrigeration with air purification and liquefaction processes, so that air can be purified without the assistance of external heat sources during low energy consumption periods, and low-peak electricity, wind power, and photovoltaic power can be stored in liquid form. Since the heat energy generated by the vortex tube can be used to heat and regenerate the desorption device, no external heat source is required. At the same time, the hot air flow can also blow out impurity gases, thereby saving energy and improving the energy storage efficiency of the liquid air energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural diagram of the liquid air energy storage system combined with eddy current refrigeration of the present invention;

[0019] In the figure: air purification unit 1, air compressor 101, first vortex tube 102, adsorption device 103, desorption device 104, control valve 105, liquid air energy storage unit 2, compressor unit 201, first heat exchanger 202, second storage tank 203, first storage tank 204, second vortex tube 205, third heat exchanger 206, cold storage device 207, pressure reduction device 208, third storage tank 209, cryogenic pump 210, cooling device 211, second heat exchanger 212, expansion unit 213;

[0020] The implementation, functional features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0021] In order to more clearly and completely illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings.

[0022] Please refer to Figure 1 The present invention proposes a liquid air energy storage system combined with eddy current refrigeration, comprising an air purification unit 1 and a liquid air energy storage unit 2, wherein:

[0023] The liquid air energy storage unit 2 includes a compressor unit 201 at the compression end;

[0024] The air purification unit 1 includes an air compressor 101, a first vortex tube 102, an adsorption device 103 and a desorption device 104, wherein the outlet end of the air compressor 101 is connected to the first vortex tube 102, a cold end branch and a hot end branch of the first vortex tube 102 are respectively connected to the inlet of the adsorption device 103 and the inlet of the desorption device 104, another cold end branch and another hot end branch of the first vortex tube 102 are respectively connected to the inlet of the desorption device 104 and the inlet of the adsorption device 103, the outlet ends of the desorption device 104 and the adsorption device 103 are connected to the inlet end of the compressor unit 201, and a regulating valve 105 is provided on the two cold end branches and the two hot end branches of the first vortex tube 102.

[0025] In this embodiment:

[0026] The air compressor 101 is used for pressurizing and delivering air;

[0027] The first vortex tube 102 is a medium-low pressure vortex tube used to convert air into cold and hot air flows;

[0028] The adsorption device 103 is used to remove impurity gases in the air;

[0029] The desorption device 104 is used to desorb and purge impurity gases;

[0030] The regulating valve 105 is used to switch the adsorption device 103 and the desorption device 104 to operate alternately;

[0031] Specifically, medium and low pressure compressed air can be converted through a vortex tube to generate a cold airflow at one end and a hot airflow at the other end. The vortex tube can also adjust the flow and temperature of the cold and hot gases by adjusting the control valve 105. When energy consumption is low, driven by low-valley electricity or wind power or photovoltaic power, the air enters the air compressor 101 for pressurization and is transported into the first vortex tube 102, and then cold and hot airflows are generated. The cold airflow enters the adsorption device 103 to remove the impurity gas carried in the air, and the hot airflow enters the desorption device 104 for heating and regeneration. The desorbed impurity gas is swept by the hot airflow, and the desorbed The device 104 and the adsorption device 103 are regulated and operated alternately through the regulating valve 105. The regulating valve 105 can realize flexible regulation of the operating status of the adsorption device 103 and the desorption device 104 and the flow rate, temperature and other parameters of the cold and hot air flows. Since the vortex tube can complete regeneration without an external heat source, it can achieve air purification without the assistance of an external heat source during low energy consumption, and store the low-valley electricity or wind and photovoltaic energy in the form of liquid air, thereby improving the energy utilization rate of the entire system. While being able to improve the air adsorption purification efficiency, it will not increase the energy consumption of the liquid air energy storage system.

[0032] In one embodiment, the air to be purified or the adsorption device 103 may be cooled by the cold end heat exchanger of the first vortex tube 102 , and the purge gas or the desorption device 104 may be heated by the hot end heat exchanger of the first vortex tube 102 .

[0033] Furthermore, the liquid air energy storage unit 2 also includes a first heat exchanger 202, a second heat exchanger 212, a first storage tank 204 and a second storage tank 203. One end of the first heat exchanger 202 is connected to the first storage tank 204, the second heat exchanger 212 and the second storage tank 203 in sequence, and the outlet of the second storage tank 203 is connected to the other end of the first heat exchanger 202.

[0034] In this embodiment:

[0035] The first heat exchanger 202 is used to recover compression heat;

[0036] The second heat exchanger 212 is used to provide heat for air expansion;

[0037] The first storage tank 204 is used to store high-temperature medium;

[0038] The second storage tank 203 is used to store normal temperature medium;

[0039] Specifically, when energy consumption is low, the compression heat in the liquid air energy storage unit 2 is exchanged through the first heat exchanger 202, and the heat storage medium in the first heat exchanger 202 is heated and stored in the first storage tank 204. When energy consumption is peak, the heat storage medium in the first storage tank 204 supplies heat to the inlet end of the expansion unit 213 in the liquid air energy storage system through the second heat exchanger 212.

[0040] Furthermore, the liquid air energy storage unit 2 also includes a second vortex tube 205, a cold storage device 207 and a third storage tank 209. The outlet end of the compressor unit 201 is connected to the first heat exchanger 202 and the second vortex tube 205 in sequence, and the cold end of the second vortex tube 205 is connected to the cold storage device 207 and the third storage tank 209 in sequence.

[0041] In this embodiment:

[0042] The second vortex tube 205 is a medium and high pressure vortex tube;

[0043] The cold storage device 207 is used to recover the cold energy of air vaporization and provide cold energy for air liquefaction;

[0044] The third storage tank 209 is used to store liquid air;

[0045] Specifically, after the air is compressed by the compressor unit 201 and becomes high-pressure air, it is cooled to room temperature through the first heat exchanger 202. The high-pressure air at room temperature flows into the second vortex tube 205 and generates cold and hot air flows. The cold air flow is converted into liquid after being cooled by the cold storage device 207 and reduced in pressure by the pressure reduction device 208 and enters the third storage tank 209 for storage.

[0046] In one embodiment, in addition to using the pressurized air participating in the liquid air energy storage unit 2, the inlet air source of the second vortex tube 205 can also adopt an independent vortex refrigeration cycle. The pressurized air can be cooled by the cold end heat exchanger of the second vortex tube 205, and the heat energy released by the hot end heat exchanger of the second vortex tube 205 can be stored and recovered.

[0047] Furthermore, the liquid air energy storage unit 2 also includes a third heat exchanger 206, the hot end of the second vortex tube 205 is connected to the inlet end of the third heat exchanger 206 and the cold storage device 207 in sequence, and one outlet end of the second storage tank 203 is connected to the third heat exchanger 206, and is connected from the outlet end of the third heat exchanger 206 to the inlet end of the first storage tank 204.

[0048] In this embodiment:

[0049] The third heat exchanger 206 recovers the heat of the hot air flow generated by the second vortex tube 205;

[0050] Specifically, the hot air flow generated in the second vortex tube 205 enters the third heat exchanger 206, and the heat exchange medium in the second storage tank 203 enters the third heat exchanger 206 to absorb the heat of the hot air flow. After releasing the heat, the hot air flow merges with the cold air flow and enters the cold storage device 207 for further cooling. It is converted into a normal pressure liquid through the pressure reduction of the pressure reduction device 208 and stored in the third storage tank 209.

[0051] Furthermore, the liquid air energy storage unit 2 also includes a cooling device 211 and an expansion unit 213. The outlet end of the third storage tank 209 is connected to the cold storage device 207, the second heat exchanger 212 of the cooling device 211 and the expansion unit 213 in sequence.

[0052] In this embodiment:

[0053] The cooling device 211 can absorb cold energy and provide cooling to the outside;

[0054] Specifically, during peak energy consumption periods, the liquid air in the third storage tank 209 is pressurized and transported by the low-temperature pump 210 into the cold storage device 207 to release cold energy and vaporize. The vaporized low-temperature air releases cold energy again through the cooling device 211, and then flows into the second heat exchanger 212 for heating. The heated air enters the expansion unit 213 for expansion and power generation. During peak energy consumption periods, the cold energy of the low-temperature air at the outlet of the third storage tank 209 can be supplied to the outside, and the excess heat energy other than heating the expander inlet air can be used for heating.

[0055] Furthermore, a pressure reducing device 208 is provided between the cold storage device 207 and the inlet end of the third storage tank 209 , and a low-temperature pump 210 is provided between the outlet end of the third storage tank 209 and the cold storage device 207 .

[0056] Specifically, the pressure reducing device 208 is used to reduce the pressure of the cryogenic air and convert the air into a liquid state at normal pressure and store it in the third storage tank 209 , and the cryogenic pump 210 is used to pressurize and transport the liquid air.

[0057] In summary, during the energy consumption valley, driven by valley electricity or wind power or photovoltaic power, air enters the air compressor 101 for pressurization and transportation, enters the first vortex tube 102 to generate cold air flow and hot air flow, and the cold air flow enters the adsorption device 103 to remove impurity gases in the air, and the hot air flow enters the desorption device 104 for heating and regeneration, desorbs and blows out impurity gases, and the purified air flows into the compressor unit 201, where the air is compressed and generates compression heat. The pressurized air flows through the first heat exchanger 202 and transfers the heat to the heat storage medium through the first heat exchanger 202. The heated heat storage medium is stored in the first storage tank 204, and the cooled pressurized air passes through the second vortex tube 205 to generate cold air flow and hot air flow. The hot air flow passes through the third heat exchanger 206 to release heat again, and then merges with the cold air flow and enters the cold storage device 207 together. After further cooling by the cold storage device 207 and depressurization by the depressurization device 208, the liquid is stored in the third storage tank 209.

[0058] During peak energy consumption, liquid air flows out of the third storage tank 209, is pressurized and transported by the low-temperature pump 210 into the cold storage device 207 to release cold energy and vaporize, and then enters the cooling device 211 to further release cold energy, and finally converted into air at room temperature and enters the second heat exchanger 212. The heat storage medium in the first storage tank 204 enters the second heat exchanger 212 for heat exchange. The heat storage medium after releasing heat is stored in the second storage tank 203, and the room temperature air is heated and enters the expansion unit 213 to expand and generate electricity.

[0059] Of course, the present invention may have many other implementations. Based on this implementation, other implementations obtained by ordinary technicians in this field without any creative work are all within the scope of protection of the present invention.

Claims

1. A liquid air energy storage system combined with eddy current refrigeration, characterized in that: It includes an air purification unit and a liquid air energy storage unit, wherein: The liquid air energy storage unit includes a compressor unit at the compression end; The air purification unit includes an air compressor, a first vortex tube, an adsorption device and a desorption device, wherein the outlet end of the air compressor is connected to the first vortex tube, a cold end branch and a hot end branch of the first vortex tube are respectively connected to the inlet of the adsorption device and the inlet of the desorption device, another cold end branch and another hot end branch of the first vortex tube are respectively connected to the inlet of the desorption device and the inlet of the adsorption device, the outlet ends of the desorption device and the adsorption device are connected to the inlet end of the compressor unit, and regulating valves are provided on the two cold end branches and the two hot end branches of the first vortex tube.

2. The liquid air energy storage system combined with eddy current refrigeration according to claim 1, characterized in that: The liquid air energy storage unit also includes a first heat exchanger, a second heat exchanger, a first storage tank and a second storage tank. One end of the first heat exchanger is connected to the first storage tank, the second heat exchanger and the second storage tank in sequence, and the outlet of the second storage tank is connected to the other end of the first heat exchanger.

3. The liquid air energy storage system combined with eddy current refrigeration according to claim 2, characterized in that: The liquid air energy storage unit also includes a second vortex tube, a cold storage device and a third storage tank. The outlet end of the compressor unit is connected to the first heat exchanger and the second vortex tube in sequence, and the cold end of the second vortex tube is connected to the cold storage device and the third storage tank in sequence.

4. The liquid air energy storage system combined with eddy current refrigeration according to claim 3 is characterized in that: The liquid air energy storage unit also includes a third heat exchanger, the hot end of the second vortex tube is connected to the third heat exchanger and the inlet end of the cold storage device in sequence, one outlet end of the second storage tank is connected to the third heat exchanger, and is connected from the outlet end of the third heat exchanger to the inlet end of the first storage tank.

5. The liquid air energy storage system combined with vortex refrigeration according to claim 4 is characterized in that: The liquid air energy storage unit also includes a cooling device and an expansion unit. The outlet end of the third storage tank is connected to the cooling device, the cooling device, the second heat exchanger and the expansion unit in sequence.

6. The liquid air energy storage system combined with vortex refrigeration according to claim 5, characterized in that: A pressure reducing device is also provided between the cold storage device and the inlet end of the third storage tank.

7. The liquid air energy storage system combined with vortex refrigeration according to claim 5, characterized in that: A low-temperature pump is also provided between the outlet end of the third storage tank and the cold storage device.

Images