Underground aquifer type compressed air energy storage power station

Abstract

The utility model provides an underground aquifer type compressed air energy storage power station which comprises a ground unit system and further comprises an underground aquifer, underground water is arranged below the aquifer, a cover layer is arranged above the aquifer, a gas injection pipe and a gas production pipe which are parallel are communicated between the ground unit system and the aquifer, and the underground aquifer type compressed air energy storage power station further comprises a drainage pipe. One end of the drainage pipe is located in underground water, the other end of the drainage pipe is located on the ground, variable-pressure and constant-pressure combined operation can be achieved, and large-scale installation of the small-reservoir-capacity aquifer reservoir is met; heat energy / cold energy of the aquifer can be brought out in the drainage and water resorption processes, and cold and heat combined supply can be achieved; due to the fact that the contact interface of water and compressed air in the aquifer gas storage is large, conduction and energy storage can be carried out on temperature changes generated in the compressed air injection and production process through water, and the storage energy of the compressed air is improved under the same pressure.

Description

TECHNICAL FIELD

[0001] The utility model relates to compressed air energy storage field especially relates to a compressed air energy storage power station of underground aquifer formula. BACKGROUND

[0002] The gas storage device is a key link of the compressed air energy storage system, and has an important influence on efficient, stable and safe operation of the system. The aquifer is a kind of underground natural structure, and has a wide application prospect in the field of compressed air energy storage due to large gas storage scale and low construction cost. The principle of aquifer gas storage is to press compressed air into a porous stratum with high permeability, and to discharge underground water to form a large air bubble, and the space is used for storing gas. The operation mode of the aquifer storage is generally constant pressure operation, which is beneficial to the compressor and the expander. However, since the constant pressure is determined by the water head, the operation pressure of the aquifer with shallow depth is small. In addition, the available storage capacity of the aquifer in China is small, and it is difficult to install large-scale equipment under small pressure and storage capacity, and the economic benefit will decrease accordingly. CONTENT OF THE UTILITY MODEL

[0003] The utility model discloses a compressed air energy storage power station of underground aquifer formula, which can solve the problem that it is difficult to install large-scale equipment when the storage capacity of the aquifer is small and the depth is general.

[0004] Therefore, the utility model adopts the following technical scheme:

[0005] A compressed air energy storage power station of underground aquifer formula, comprising a ground unit system, further comprising an underground aquifer, wherein the lower part of the aquifer is provided with underground water, the upper part of the aquifer is provided with a cover layer, the ground unit system is communicated with the aquifer through parallel gas injection pipes and gas extraction pipes, and further comprising a drainage pipe, one end of the drainage pipe is located in the underground water, and the other end of the drainage pipe is located on the ground.

[0006] On the basis of the above technical scheme, the utility model can further adopt the following technical scheme, or use these further technical schemes in combination:

[0007] The upper end of the gas injection pipe and the gas extraction pipe on the ground is connected with the ground unit system through a total pipe.

[0008] The part of the gas extraction pipe on the ground is provided with a first valve.

[0009] The part of the drainage pipe on the ground is provided with a second valve.

[0010] The part of the drainage pipe on the ground is provided with a pressure gauge.

[0011] The lower ports of the gas injection pipe and the gas extraction pipe are located on the same horizontal line.

[0012] The gas injection pipe and the gas extraction pipe have the same height.

[0013] The aquifer is an anticline aquifer.

[0014] The cover layer has a burial depth of 700 m.

[0015] The underground aquifer and the underground water are provided with a gas-water interface that can be dynamically lifted.

[0016] Compared with the prior art, the underground aquifer type compressed air energy storage power station has the following advantages and beneficial effects: variable pressure and constant pressure combined operation can be realized, large-scale installation of small reservoir capacity aquifer storage can be met, the process of water drainage and water suction can take out the heat / cold energy of the aquifer, cold and heat supply can be realized, the contact interface of water and compressed air of the aquifer storage is large, the temperature change generated in the process of compressed air injection and extraction can be conducted and stored through water, and the storage energy of compressed air is improved under the same pressure. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a cross-sectional structure schematic view of the utility model. DETAILED DESCRIPTION

[0018] In order to make the skilled in the art better understand the technical scheme of the utility model, the preferred implementation scheme of the utility model is described below in combination with specific embodiments, and examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar functional elements throughout, but it should be understood that the drawings are only for illustrative description and cannot be understood as limiting the utility model; in order to better illustrate the embodiments, some components in the drawings can be omitted, enlarged or reduced, and the size of the actual product is not represented; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings can be omitted, and the positional relationship described in the drawings is only for illustrative description and cannot be understood as limiting the utility model.

[0019] The utility model is further described below in combination with the drawings and embodiments, but it is not used as the basis for limiting the utility model.

[0020] The utility model provides a kind of underground aquifer type compressed air energy storage power station, including ground unit system 1, still include aquifer 6, the lower of aquifer 6 is equipped with underground water 7, the upper of aquifer 6 is equipped with cover layer 5, ground unit system 1 is communicated with aquifer 6 and has parallel gas injection pipe 2 and gas extraction pipe 3, still include drain pipe 4, one end of drain pipe 4 is located in underground water 7, the other end of drain pipe 4 is located on ground.

[0021] The upper end of the injection pipe 2 and the gas extraction pipe 3 on the ground is connected to the ground unit system 1 after being connected to the main pipe 23.

[0022] The part of the gas extraction pipe 3 on the ground is provided with a first valve 9, and the independent or synchronous operation of the injection pipe 2 and the gas extraction pipe 3 is realized by arranging the first valve 9. When storing energy, the first valve 9 is closed, and only the injection pipe 2 transports compressed air. When releasing energy, the first valve 9 is opened, and the injection pipe 2 and the gas extraction pipe 3 together transport gas, which meets the rate difference caused by the length of time of storing energy and the length of time of releasing energy of the compressed air power station.

[0023] The part of the drainage pipe 4 on the ground is provided with a second valve 11.

[0024] The drainage pipe 4 discharges water at the initial stage of operation in the aquifer 6, and the volume of discharged water is the gas storage capacity of the aquifer 6, and is closed through the second valve 11 in the later stage.

[0025] The part of the drainage pipe 4 on the ground is provided with a pressure gauge 10, which plays a supporting role in pressure recording and whether a leakage occurs.

[0026] The lower ports of the injection pipe 2 and the gas extraction pipe 3 are located on the same horizontal line.

[0027] The injection pipe 2 and the gas extraction pipe 3 have the same height.

[0028] The injection pipe 2, the gas extraction pipe 3 and the drainage pipe 4 all pass through the caprock 5 of the aquifer 6 and are strictly sealed in the wellbore. The injection pipe 2 and the gas extraction pipe 3 have consistent vertical lengths, and the lower ports of the two are located in the upper part of the aquifer 6, while the lower port of the drainage pipe 6 is located in the deep part of the aquifer 6 and does not break through the sealing rock layer below the aquifer 6.

[0029] The aquifer 6 is a anticline aquifer.

[0030] The burial depth of the caprock 5 is 700 m.

[0031] The gas-water interface 8 between the underground aquifer 6 and the underground water 7 is dynamically adjustable.

[0032] In this embodiment, the capacity of the anticline aquifer 6 is up to 80,000 square meters. According to the information such as the lithology and thickness of the caprock, the maximum pressure of the aquifer 6 is designed to be 1.5 times the hydrostatic pressure, and the operation pressure is designed to be variable between 7-10 MPa and constant at 7 MPa.

[0033] The working process of the underground aquifer type compressed air energy storage power station in this embodiment is as follows:

[0034] When storing energy, the first valve 9 is closed, and when the aquifer 6 is in compressed air energy storage operation, the ground unit system 1 injects the air into the aquifer 6 through the injection pipe 2 after the air is changed into gas with certain temperature and pressure. The gas pressure slowly discharges the original water to the ground through the drainage pipe 4. When the volume of the discharged water reaches the preset value, the second valve 11 is closed. At this time, the aquifer 6 forms a closed area, and the gas-water interface 8 remains constant. When the pressure reaches the designed maximum pressure value, the injection is stopped, and at this time, the compressed air energy storage link is completed, and the gas-water interface of the storage remains at the anticlinal arc, ensuring the sealing property.

[0035] When releasing energy, the first valve 9 of the injection pipe 2 and the gas extraction pipe 3 is opened, and the injection pipe 2 and the gas extraction pipe 3 simultaneously extract gas. With the extraction of the gas, the compressed gas in the aquifer 6 gradually decreases from 10 MPa to 7 MPa, and the static water pressure is constant. When the pressure of the aquifer 6 reaches the static water pressure, the second valve 11 is opened, and the discharged water is sucked back into the aquifer 6, so that the residual gas amount is reduced, and the storage performance of the aquifer 6 is fully utilized. With the balance of the back suction and the gas extraction, the gas extraction pressure is maintained at about 7 MPa, the water in the aquifer gradually occupies the position of the gas, and the amount of the gas is less and less until the power generation demand is reached. The back suction amount is designed according to the installed capacity and the power generation time length. After the power generation time length is reached, the valve is closed, and the gas extraction is stopped.

[0036] Compared with the constant pressure condition, the storage mode increases the energy in the pressure change interval of 10-7 MPa, and the installed capacity can be increased by one half on the basis of the original installed capacity.

[0037] According to the description and the drawings of the utility model, the underground aquifer type compressed air energy storage power station of the utility model can be easily manufactured or used by the person skilled in the art, and the positive effects recorded in the utility model can be generated.

[0038] It should be noted that the terms "include" and "have" and any variations thereof in the specification and claims of the utility model and the above drawings are intended to cover non-exclusive inclusion. The terms "mount", "set", "provided with", "connected", "connected", "sleeved" should be understood in a broad sense. For example, it can be fixedly connected, detachably connected, or integrally configured; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication between two mechanisms, elements or components. For the person skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0039] In the description of the utility model, it is understood that the terms "one end", "the other end", "outer side", "inner side", "horizontal", "end", "length", "outer end", "left", "right" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the indicated mechanism or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the utility model. The terms "first", "second" are only used for the convenience of description, and do not indicate or imply relative importance.

[0040] In addition, in the practice of the claims of the utility model, those skilled in the art can understand and affect the changes of the disclosed embodiments through the study of the drawings, the disclosure and the attached claims. In addition, in the claims, the specification, "including", "containing" and the like do not exclude other elements or steps, and the singular does not exclude the plural.

[0041] The above is only a preferred embodiment of the utility model, and is not intended to limit the scope of the utility model, that is, any equivalent changes and modifications made according to the utility model are covered by the scope of the claims of the utility model, which will not be listed one by one here.

Claims

1. An underground aquifer-type compressed air energy storage power station, comprising a ground unit system (1), characterized in that: It also includes an aquifer (6), underground water (7) is provided below the aquifer (6), a cap layer (5) is provided above the aquifer (6), and a parallel gas injection pipe (2) and a gas production pipe (3) are connected between the ground unit system (1) and the underground aquifer (6). It also includes a drainage pipe (4), one end of the drainage pipe (4) is located in the ground water (7), and the other end of the drainage pipe (4) is located on the ground.

2. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: The above-ground ends of the gas injection pipe (2) and the gas production pipe (3) are connected to the main pipe (23) and then communicated with the ground unit system (1).

3. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: The portion of the gas production pipe (3) located above ground is provided with a first valve (9).

4. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: The portion of the drainage pipe (4) located above ground is provided with a second valve (11).

5. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: The portion of the drainage pipe (4) located above ground is provided with a pressure gauge (10).

6. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: The lower ends of the gas injection pipe (2) and the gas collection pipe (3) are located on the same horizontal line.

7. An underground aquifer-type compressed air energy storage power station according to claim 1 or 6, characterized in that: The gas injection pipe (2) and the gas collection pipe (3) have the same height.

8. The underground aquifer-type compressed air energy storage power station according to claim 1, characterized in that: The aquifer (6) is an anticline aquifer.

9. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: The buried depth of the cap layer (5) is 700m.

10. The underground aquifer type compressed air energy storage power station according to claim 1, characterized in that: A gas-water interface (8) that can be dynamically raised and lowered is provided between the underground aquifer (6) and the groundwater (7).

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