Oscillating water column type compressed air energy storage method based on wave energy conversion

Abstract

The invention provides an oscillating water column type compressed air energy storage method based on wave energy conversion, belongs to the field of compressed air energy storage, and is realized by compressing gas by utilizing energy of waves in an oscillating water column cavity. The oscillating water column type compressed air energy storage method is achieved through an oscillating water column cavity, a gas one-way valve, a gas conveying pipeline and a gas storage tank, a wave inlet, an embankment and a gas outlet are formed in the oscillating water column cavity, and the oscillating water column cavity enables gas to be compressed or expanded by forming a water column oscillating up and down; the gas is pumped into a gas storage tank through a gas conveying pipeline through a gas one-way valve, a main body part of the gas conveying pipeline is arranged in the marine environment, and power in the gas compression process comes from kinetic energy of waves of an oscillating water column cavity. Air compression and storage can be achieved in a green and low-energy-consumption mode; the low-energy-consumption seawater cooling effect can be achieved, and an additional cooling device does not need to be installed.

Description

Technical Field

[0001] The present invention belongs to the field of compressed air energy storage, and relates to an oscillating water column type compressed air energy storage method based on wave energy conversion. The oscillating water column type compressed air energy storage method can be used for green and low-energy compressed air energy storage. Background Art

[0002] Large-scale enterprise factories always need a large amount of energy supply to keep the equipment working properly. The cost of electricity is very different in different periods of time. The price of peak electricity is higher than that of valley electricity. Considering the huge electricity consumption of large factories, even a small price difference needs to be fully considered in the context of a large base. In order to reduce the electricity bill expenditure under the same power consumption, some companies have come up with the strategy of storing energy during valley hours and using electricity during peak hours. The current hot spot for energy storage is "compressed air energy storage", which is a storage method that uses the surplus electricity during the low load of the power grid to compress air, store it in a high-pressure sealed facility, and release it during the peak power consumption period to drive gas turbines or steam turbines to generate electricity. The principle is to use electricity to drive the air compressor to compress air during the low load period of the power grid, store it in a high-pressure container, and release the compressed air during the peak load period of the power grid to drive the steam turbine to generate electricity, thereby meeting the power demand.

[0003] Existing compressed air energy storage mainly includes "compression stage", "gas storage stage", "heat storage stage", "heat recovery stage" and "expansion power generation stage". In the traditional form, the compression stage requires a large amount of electrical energy to inject the gas into the high-pressure sealed tank, and the gas needs to be cooled in the gas storage stage to prevent the temperature from being too high and causing the overall pressure to drop. Considering that compressed air energy storage is ushering in an opportunity for rapid development driven by the "dual carbon" goals, the energy consumption in the compression stage and the cooling problem in the gas storage stage are solved by using waves in the marine environment. The energy of wave movement can compress air with low energy consumption, and the natural environment of ocean waves can also have a good cooling effect. At present, people have done a lot of research on devices that utilize wave energy.

[0004] In terms of compressed air energy storage, most of the current scholars focus on the "heat exchanger" components in the overall device, and a large amount of electricity is still required to compress and store air. For example, a temperature balance structure and method of a compressed air energy storage heat exchanger (Chinese invention patent, publication number CN118502517A) and a heat exchanger operation control method and system for a compressed air energy storage device (Chinese invention patent, publication number CN118963447A), both of which use traditional electric energy to drive the compressor to achieve gas storage in the gas storage stage. The heat exchanger part designed later can detect the water temperature changes near the components in the compressed air energy storage, and can adjust the working parameters of the water pump in time according to the set temperature to adapt to the changing working conditions, thereby ensuring the efficiency and reliability of the operation. However, whether it is in the compressed air storage stage or the subsequent heat exchange work stage, it needs to consume more electricity to achieve normal operation, which causes great energy consumption and goes against the country's green development plan.

[0005] Compared with the traditional air compression energy storage method, the present invention uses the energy of the waves themselves to compress the gas, which does not require the consumption of electricity and is more green, economical and environmentally friendly. At the same time, the direct use of seawater for cooling also reduces costs and saves the space occupied by the cooling equipment originally installed on land. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides an oscillating water column type compressed air energy storage method based on wave energy conversion. The present invention organically combines the traditional compressed air energy storage device and the oscillating water column type wave energy storage device into one according to their respective working principles and compatible spatial layout. The present invention can directly convert the kinetic energy of the waves into the internal energy of the gas and store it in a high-pressure sealed gas storage tank. Compared with the gas storage method in the prior art, it reduces power consumption and can realize the compressed storage of air in a greener and lower energy consumption manner. Moreover, the gas transmission pipeline part is placed in the natural marine environment in the present invention, which can achieve a low-energy seawater cooling effect without the need to install additional cooling devices. This organic combination of the wave energy device and the air compression energy storage device can greatly consume the wave energy at the front end, and while realizing green and low-energy compressed air, it can also play a role in embankment protection.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] An oscillating water column type compressed air energy storage method based on wave energy conversion, the oscillating water column type compressed air energy storage method is realized by an oscillating water column chamber, a gas one-way valve 9, a gas pipeline 11 and a gas storage tank 10, wherein the oscillating water column chamber is provided with a wave inlet 1, a levee 2, and an air outlet 5. When in use, it is fixed on the coast through the levee 2 of the oscillating water column chamber, and the fixed position requires that the wave inlet 1 of the oscillating water column chamber is located below the sea surface, and the energy of the waves in the oscillating water column chamber is used to compress the gas. Specifically: the oscillating water column chamber compresses or expands the gas by forming a water column that oscillates up and down, and injects it into the gas storage tank 10 through the gas pipeline 11 through the gas one-way valve 9. The main part of the gas pipeline 11 is arranged in the marine environment, and the power of the gas compression process comes from the kinetic energy of the waves in the oscillating water column chamber.

[0009] The oscillating water column chamber is an irregular structure, and a water column 3 and an air chamber 4 are formed in the oscillating water column chamber. The air chamber 4 is located above the water column 3. The embankment 2 is arranged at the rear side of the oscillating water column chamber, and the wave inlet 1 is arranged at the front side and below the oscillating water column chamber. Seawater enters the interior through the wave inlet 1 to form a water column 3. The air outlet 5 is arranged at the top of the oscillating water column chamber. The air chamber 4 is connected to one end of the gas pipeline 11 through the air outlet 5, and the other end of the gas pipeline 11 is connected to the gas storage tank 10, and a gas one-way valve 9 is installed on the gas pipeline 11 at the outlet of the gas outlet 5.

[0010] Furthermore, the lower part of the oscillating water column chamber, i.e., the part under water, is a regular structure, and the upper part, i.e., the part above water, is an irregular structure, and the size of the structural opening from the upper end of the air chamber 4 to the air outlet 5 is uniformly reduced, which is convenient for effectively compressing the air. The air outlet 5 is designed with a slope, so that the flow rate of the air gradually increases after being compressed, which is convenient for the compressed air to enter the high-pressure sealed air storage tank 10.

[0011] Furthermore, the oscillating water column chamber is designed to be closed all around, with only the wave inlet 1 at the wave-facing side of the lower end and the air outlet 5 at the upper end of the device connected to the gas one-way valve 9 being open.

[0012] Furthermore, the conversion efficiency of the wave energy conversion device is controlled by controlling the size of the wave inlet 1. At the same time, the size of the wave inlet 1 will affect the flow rate of the compressed air. In order to make the final flow rate of the compressed air meet the industrial production operation specifications, the size of the wave inlet 1 needs to be designed and optimized according to the actual situation: for example, in order to reduce the fluctuation amplitude of the water surface in the air chamber 4, the opening size of the lower wave inlet 1 can be reduced. If a larger water surface fluctuation amplitude is desired, the size of the wave inlet 1 can be increased; in order to achieve a better compressed air effect, a suitable size of the wave inlet 1 can be selected to make the oscillation of the water surface in the air chamber 4 consistent with the frequency of the waves outside, and the resonance effect can be used to improve the overall air compression efficiency; the size and shape of the wave inlet 1 are also related to the structural strength of the device. A larger opening requires a stronger structure to withstand the impact of the waves, while a smaller opening may be more economical in structure, but it will sacrifice some performance.

[0013] Furthermore, the embankment 2 enables the oscillating water column wave energy conversion device to form a closed air chamber, thereby facilitating the gas to be pumped into the high-pressure sealed gas storage tank 10. At the same time, a gas check valve 9 and a gas storage tank 10 can also be arranged on the upper rear part of the embankment 2 to save land space. The embankment 2 described here can be a structure that extends to the shore and is firmly on the ground, or it can be based on the existing natural environment terrain as a carrier.

[0014] Furthermore, the water column 3 moves upward after the waves enter the chamber of the oscillating water column device, compressing the air in the upper part, so that the air is compressed in one direction and enters the air storage tank 10, thereby realizing green and low-energy consumption air storage.

[0015] Furthermore, the gas pipeline 11 is placed in seawater and uses natural seawater for cooling, thereby saving cooling costs and the space occupied by land cooling equipment.

[0016] Furthermore, the gas storage tank 10 can be placed at a designated planned location on land for temporary storage of compressed air, and connected to the gas one-way valve 9 via the gas pipeline 11. It can release compressed air to generate electricity during the low load period of the power grid, thereby meeting electricity demand.

[0017] The present invention aims to provide an idea of ​​an oscillating water column compressed air energy storage method based on wave energy conversion. As for how the size of the wave inlet should be set to ensure both the motion effect of the wave and the compression effect of the air, the structural dimensions of the traditional oscillating water column wave energy device cannot be simply copied, and should be modified according to actual conditions. In terms of the layout of the gas pipeline, the position and depth in the seawater and the length requirements of the gas pipeline for cooling should be comprehensively considered in combination with the actual compressed air temperature and the corresponding water temperature in the sea area.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1) The oscillating water column chamber of the present invention uses a powerful hydraulic force to compress the gas into the gas storage tank with low energy consumption, which has excellent performance and is green and environmentally friendly. That is, the present invention uses wave energy to compress air and uses hydraulic pressure to achieve green and low-energy compressed air energy storage.

[0020] 2) Since the temperature needs to be kept low during the gas storage stage of compressed air energy storage, the present invention places the gas pipeline in the marine environment. The natural marine environment can have a good cooling effect, that is, the natural marine environment is used to cool the compressed air, which greatly saves cooling costs and the floor space of onshore cooling equipment, and realizes green and effective compressed air energy storage.

[0021] 3) The present invention absorbs the energy of waves and uses it to compress gas, which can effectively weaken the energy of the waves themselves and has a certain effect on protecting embankments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0023] Figure 2 is a front view of the present invention;

[0024] Figure 3 is a rear view of the present invention;

[0025] Figure 4 It is a left side view of the present invention;

[0026] Figure 5 It is a right side view of the present invention;

[0027] Figure 6 is a top view of the present invention;

[0028] Figure 7 is a bottom view of the present invention;

[0029] Figure 8 It is a schematic diagram of the overall two-dimensional structure of an oscillating water column type compressed air energy storage method based on wave energy conversion of the present invention;

[0030] Fig. 9 It is a schematic diagram of the internal structure of a gas one-way valve in an oscillating water column type compressed air energy storage method based on wave energy conversion of the present invention;

[0031] Fig.10 It is a schematic diagram of the layout and connection of the gas pipeline;

[0032] In the figure: 1 wave inlet; 2 embankment; 3 water column; 4 air chamber; 5 air outlet; 6 valve body; 7 valve core; 8 spring; 9 gas check valve; 10 gas storage tank; 11 gas transmission pipeline. DETAILED DESCRIPTION

[0033] The present invention is described in detail below with reference to the accompanying drawings.

[0034] The present embodiment provides an oscillating water column type compressed air energy storage method based on wave energy conversion, which is realized by an oscillating water column chamber, a gas one-way valve 9, a gas pipeline 11 and a gas storage tank 10, wherein the oscillating water column chamber is provided with a wave inlet 1, a levee 2 and an air outlet 5. When in use, it is fixed on the coast through the levee 2 of the oscillating water column chamber, and the fixed position requires that the wave inlet 1 of the oscillating water column chamber is located below the sea surface, and the energy of the waves in the oscillating water column chamber is used to compress the gas. Specifically: the oscillating water column chamber compresses or expands the gas by forming a water column that oscillates up and down, and injects it into the gas storage tank 10 through the gas pipeline 11 through the gas one-way valve 9. The main part of the gas pipeline 11 is arranged in the marine environment, and the power of the gas compression process comes from the kinetic energy of the waves in the oscillating water column chamber.

[0035] The oscillating water column chamber is an irregular structure, in which a water column 3 and an air chamber 4 are formed. The air chamber 4 is located above the water column 3, the embankment 2 is arranged at the rear side of the oscillating water column chamber, and the wave inlet 1 is arranged at the front and lower side of the oscillating water column chamber. Seawater enters the interior through the wave inlet 1 to form a water column 3, and the air outlet 5 is arranged at the top of the oscillating water column chamber. The air chamber 4 is connected to one end of the gas pipeline 11 through the air outlet 5, and the other end of the gas pipeline 11 is connected to the gas storage tank 10, and a gas one-way valve 9 is installed on the gas pipeline 11 at the outlet of the air outlet 5; the middle part of the gas pipeline 11 is the main part, which is placed below the sea surface. The main structure of the oscillating water column is closed all around, and only the wave inlet 1 at the lower end facing the waves and the air outlet 5 at the upper end of the device connected to the gas one-way valve 9 are open. The oscillating water column chamber is connected to the oscillating water column chamber from Figure 5 , Figure 8 It can be seen that the structure of the underwater part is relatively regular, and the upper part of the structure becomes thinner and thinner, especially the size of the structural opening from the upper end of the air chamber 4 to the air outlet 5 is uniformly reduced, that is, the air outlet 5 adopts a slope design.

[0036] The gas one-way valve 9 can be purchased as a standard part, and its internal structure includes a valve body 6, a valve core 7 and a spring 8. By observing the entire gas one-way valve 9, it can be seen that after the gas is compressed from the gas outlet 5, it enters the valve core 7 inside the valve body 6 from its left side. The continuous influx of gas will push and compress the spring 8 in the valve core 7 to clear the one-way passage of the gas, thereby realizing the one-way flow of the gas. The gas one-way valve 9 only passes gas in one direction to ensure the energy storage of air compression, taking into account the repeated movement of the wave water body in the oscillating water column.

[0037] See also Figure 8 , Fig.10Based on the traditional oscillating water column wave energy device, the present invention connects a gas one-way valve 9 behind the air outlet 5, uses the energy of sea waves to compress the gas in the air chamber 4 with low energy consumption, and injects the gas into the high-pressure closed gas storage tank 10 through the gas pipeline 11 through the gas one-way valve 9. In order to cool the compressed air, the gas pipeline 11 is arranged in seawater for cooling to prevent the pressure from dropping due to excessive temperature. Such an oscillating water column compressed air energy storage method based on wave energy conversion is suitable for offshore embankments in coastal areas. While storing compressed air energy in a green and low-energy manner, it can also reduce cooling costs and the space occupied by cooling equipment, and can play a certain protective role on the embankment after weakening the wave energy.

[0038] The working process of an oscillating water column compressed air energy storage method based on wave energy conversion is as follows:

[0039] During operation, external waves first enter the oscillating water column chamber from the wave inlet 1, and then form an up-and-down oscillating water column 3 in the chamber. The continuous oscillation of the water column 3 causes the gas in the air chamber 4 to repeatedly compress and expand:

[0040] When the gas expands, due to the influence of the upper gas one-way valve 9, the compressed gas will not leak out, and new gas will be replenished into the air intake chamber 4 through the wave inlet 1 at the lower end of the oscillating water column chamber, so that the air chamber 4 is refilled with gas to facilitate subsequent gas compression.

[0041] When the gas is compressed, it is connected to the gas check valve 9 through the gas outlet 5. After the compressed gas flows through the gas pipeline 11 placed in seawater for cooling, it is stored in the high-pressure sealed gas storage tank 10. The gas storage tank 10 temporarily stores the high-pressure gas. When the power grid is at its peak, the stored compressed air can be released to generate electricity, thereby meeting the demand for electricity.

[0042] The above-described embodiments merely express the implementation methods of the present invention, but they should not be understood as limiting the scope of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An oscillating water column compressed air energy storage method based on wave energy conversion, characterized in that: The oscillating water column type compressed air energy storage method is implemented by an oscillating water column chamber, a gas one-way valve (9), a gas pipeline (11) and a gas storage tank (10), wherein the oscillating water column chamber is provided with a wave inlet (1), a levee (2) and a gas outlet (5). When in use, the oscillating water column chamber is fixed on the coast through the levee (2) of the oscillating water column chamber, and the fixed position requires that the wave inlet (1) of the oscillating water column chamber is located below the sea surface; the oscillating water column chamber compresses or expands the gas by forming a water column that oscillates up and down, and the compressed gas is input into the gas storage tank (10) through the gas one-way valve (9) and the gas pipeline (11), and the main part of the gas pipeline (11) is arranged in a marine environment.

2. The oscillating water column compressed air energy storage method based on wave energy conversion according to claim 1 is characterized in that: The oscillating water column chamber is an irregular structure, wherein a water column (3) and an air chamber (4) are formed in the oscillating water column chamber, wherein the air chamber (4) is located above the water column (3), the bank (2) is arranged at the rear side of the oscillating water column chamber, the wave inlet (1) is arranged at the lower front side of the oscillating water column chamber, seawater enters the interior through the wave inlet (1) to form a water column (3), and the air outlet (5) is arranged at the top of the oscillating water column chamber.

3. The oscillating water column compressed air energy storage method based on wave energy conversion according to claim 1 is characterized in that: The gas chamber (4) is connected to one end of a gas pipeline (11) through a gas outlet (5), the other end of the gas pipeline (11) is connected to a gas storage tank (10), and a gas one-way valve (9) is installed on the gas pipeline (11) at the outlet of the gas outlet (5).

4. The oscillating water column compressed air energy storage method based on wave energy conversion according to claim 1 is characterized in that: The oscillating water column chamber has a regular structure in the underwater portion and an irregular structure in the above-water portion, and the size of the structural opening from the upper end of the air chamber (4) to the air outlet (5) decreases uniformly.

5. The oscillating water column compressed air energy storage method based on wave energy conversion according to claim 4 is characterized in that: The air outlet (5) adopts a slope design.

6. The oscillating water column compressed air energy storage method based on wave energy conversion according to claim 1 is characterized in that: The conversion efficiency of the wave energy conversion device is controlled by controlling the size of the wave inlet (1), and the size of the wave inlet (1) is designed and optimized according to actual conditions.

7. The oscillating water column compressed air energy storage method based on wave energy conversion according to claim 1 is characterized in that: The gas storage tank (10) is placed at a designated planned location on land and is used to store compressed air. During the off-load period of the power grid, the compressed air is released to generate electricity to meet the power demand.

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