CN219697510U

CN219697510U - Underground heat exchange power generation pipeline and underground power generation system

Info

Publication number: CN219697510U
Application number: CN202321265640.6U
Authority: CN
Inventors: 李克文
Original assignee: China University of Geosciences Beijing
Current assignee: China University of Geosciences Beijing
Priority date: 2023-05-24
Filing date: 2023-05-24
Publication date: 2023-09-15
Anticipated expiration: 2033-05-24

Abstract

The utility model relates to the technical field of geothermal energy thermoelectric power generation, in particular to an underground heat exchange power generation pipeline and an underground power generation system. The utility model provides a heat transfer electricity generation pipeline in pit, includes pipeline body and TEG chip, and pipeline body inner wall cross-section is circular, outer wall cross-section is the polygon of waiting, and the even laminating of TEG chip is laid on each plane of pipeline body outer wall, each TEG chip electric connection. The underground power generation system comprises a pipeline body and a sleeve pipe fitting, wherein the pipeline body and the sleeve pipe fitting are arranged in a way that the pipeline body and the sleeve pipe fitting extend into an underground high-temperature reservoir. The system can realize power generation in the underground or in the well without exchanging the heat energy of the deep part of the earth to the ground; a heat preservation pipe is not needed, so that the cost is greatly reduced; the number and the occupied area of ground facilities required by geothermal energy power generation are reduced, so that the environmental influence is reduced; the heat exchange efficiency is improved through the fin heat exchanger. The utility model is mainly applied to the aspect of underground power generation systems.

Description

Underground heat exchange power generation pipeline and underground power generation system

Technical Field

The utility model relates to the technical field of geothermal energy thermoelectric power generation, in particular to an underground heat exchange power generation pipeline and an underground power generation system.

Background

Solar photovoltaic and wind power generation have been rapidly developed in recent years, but 24-hour continuous power generation cannot be achieved. If implemented, energy storage devices must be employed and installation of energy storage facilities can significantly reduce their economic efficiency. The geothermal energy has no problem in this respect as compared with it.

Well bores drilled into the earth deep, such as oil and gas wells, geothermal wells (including dry and hot rock wells), and the like, have a large amount of geothermal energy, and the mode of generating electricity by using the geothermal energy is basically to collect the thermal energy to the ground, and then technologies such as steam turbines and the like are adopted. In most cases, large-scale fracturing is needed, earthquakes can be caused in the fracturing process, the safety of lives and properties around the well is endangered, and unnecessary panic is caused in the social masses. In the process of extracting geothermal energy, a heat preservation pipe is also needed to reduce the loss of thermal energy. However, the use of insulating tubing can greatly increase the overall cost of power generation.

In order to save the cost and improve the utilization efficiency of geothermal energy, a semiconductor thermoelectric power generation device can be used in the development process of geothermal resources. However, most of the existing semiconductor thermoelectric power generation devices and power generation systems are installed at the ground instead of in wells. The main problem is that the underground pipe column commonly used at home and abroad comprises an oil pipe and a sleeve, most of the underground pipe column is cylindrical, and the existing semiconductor thermoelectric power generation chip is sheet-shaped and is difficult to be directly adhered to the surface of the pipe column. The foldable or flexible semiconductor thermoelectric generation chip can solve the shape problem, and unfortunately, the current foldable or flexible semiconductor thermoelectric generation technology is difficult to meet the requirements of underground practical application, and even ground application cannot be realized.

In addition, if the downhole semiconductor thermoelectric generation is to be realized, a large number of power generation chips are required to be installed, and the number can be from hundreds to tens of thousands or even more. How to connect these chips and deliver power to ground remains an international challenge to be solved.

Disclosure of Invention

In order to overcome the defects in the prior art, the utility model provides an underground heat exchange power generation pipeline and an underground power generation system. The system adopts a semiconductor thermoelectric power generation technology and a corresponding heat exchange technology to solve the problem that the conventional geothermal power generation fracturing causes earthquake and the heat preservation pipe to greatly increase the cost. The device does not need to adopt large-scale fracturing, ultra-deep heat pipes and heat preservation pipes, and solves the problems of low heat exchange efficiency, high cost, lamination of a semiconductor thermoelectric power generation chip and a pipe column, chip connection and underground power transmission. The geothermal power generation utilization efficiency is remarkably improved.

In order to solve the technical problems, the utility model adopts the following technical scheme:

the utility model provides a heat transfer electricity generation pipeline in pit, includes pipeline body and TEG chip, pipeline body inner wall cross-section is circular, outer wall cross-section is the polygon of waiting, the even laminating of TEG chip is laid on each plane of pipeline body outer wall, each TEG chip electric connection.

The underground power generation system comprises a pipeline body and a sleeve pipe fitting, wherein the pipeline body and the sleeve pipe fitting are arranged in a way that the pipeline body and the sleeve pipe fitting extend into an underground high-temperature reservoir part, and the sleeve pipe fitting is arranged inside or outside the pipeline body.

When the sleeve pipe fitting sets up in the pipeline body outside, the sleeve pipe fitting includes first sleeve pipe fitting and second sleeve pipe fitting, first sleeve pipe fitting sets up in the outside of pipeline body, be provided with the packer shutoff between first sleeve pipe fitting and the pipeline body, the second sleeve pipe fitting sets up between pipeline body and first sleeve pipe fitting, communicate between second sleeve pipe fitting bottom and the first sleeve pipe fitting.

When the sleeve pipe fitting is arranged inside the pipeline body, the pipeline body is arranged in a well, a passage is reserved between the pipeline body and a well wall, the bottom of the pipeline body is closed, and the sleeve pipe fitting is arranged in the pipeline body and the bottom of the sleeve pipe fitting is communicated with the pipeline body.

And a high-permeability pore canal is arranged on the high-temperature reservoir layer outside the well wall.

The utility model provides a heat transfer electricity generation pipeline in pit, includes the pipeline body, the pipeline body includes oil pipe and sleeve pipe, oil pipe sets up in the sleeve pipe, oil pipe adopts circular pipe, the sleeve pipe inner wall is circular, and the outer wall is the polygon of waiting, the sleeve pipe outer wall has evenly been laid the TEG chip, each TEG chip electric connection, the TEG chip outside is provided with the fin heat exchanger.

The utility model provides a power generation system in pit, sleeve pipe laminating high temperature reservoir sets up, the sleeve pipe bottom is sealed, oil pipe sets up in the sleeve pipe, forms oil jacket annular space between oil pipe and the sleeve pipe, oil pipe bottom and oil jacket annular space intercommunication.

And a high-permeability pore canal is arranged on the high-temperature reservoir layer outside the sleeve.

The utility model provides a U-shaped well electricity generation system in pit, includes pipeline body, oil pipe and sleeve pipe, sets up oil pipe and sleeve pipe in U-shaped well one side shaft section, the sleeve pipe sets up in the oil pipe outside, is provided with the packer between oil pipe and the sleeve pipe that is close to high temperature reservoir position, and oil pipe no longer sets up after getting into high temperature reservoir, and U-shaped well horizontal segment only is provided with the sleeve pipe, is provided with the TEG chip on the lateral wall that the sleeve pipe outside is close to high temperature reservoir, and the high permeability pore has been seted up to the high temperature reservoir part near the U-shaped well horizontal segment, is provided with the pipeline body in the vertical section of U-shaped well opposite side, is provided with first sleeve pipe spare and second sleeve pipe spare in the pipeline body outside, first sleeve pipe spare and pipeline body set up the packer shutoff at high temperature reservoir height, pipeline body downwardly extending and U-shaped well horizontal segment's sleeve pipe intercommunication.

Compared with the prior art, the utility model has the following beneficial effects:

the system can realize power generation in the underground or in the well without exchanging the heat energy of the deep part of the earth to the ground; a heat preservation pipe is not needed, so that the cost is greatly reduced; large-scale fracturing is not required to be carried out for heat collection or heat collection, so that danger and social hazard caused by earthquake in the fracturing process are not worried; the heat exchange is carried out without adopting an ultra-deep heat pipe, so that the geothermal power generation cost is further reduced; the number and the occupied area of ground facilities required by geothermal energy power generation are greatly reduced, so that the environmental influence is reduced; the heat exchange efficiency is improved through the fin heat exchanger.

Drawings

FIG. 1 is a schematic view of a portion of a pipe body according to the present utility model;

FIG. 2 is a schematic view of a portion of a sleeve according to the present utility model;

FIG. 3 is a schematic view of the tubing and casing assembly of the present utility model;

FIG. 4 is a schematic diagram of a power generation system in a vertical well;

FIG. 5 is a schematic diagram of another power generation system in a vertical well;

FIG. 6 is a schematic illustration of a power generation system with casing members disposed outside in a horizontal well;

FIG. 7 is a schematic illustration of a power generation system with casing tubing disposed therein in a horizontal well;

FIG. 8 is a schematic diagram of another power generation system in a horizontal well;

FIG. 9 is a schematic diagram of a power generation system in a U-well;

in the figure: the high-temperature pipeline comprises a pipeline body 1, a TEG chip 2, an oil pipe 3, a sleeve 4, a fin heat exchanger 5, a sleeve pipe fitting 6, a first sleeve pipe fitting 7, a second sleeve pipe fitting 8, an oil sleeve annular space 9, low-temperature fluid 10, high-temperature fluid 11, a packer 12 and a high-temperature reservoir 13.

Detailed Description

In order that the above-recited objects, features and advantages of the present utility model will be more clearly understood, a more particular description of the utility model will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It should be noted that, without conflict, the embodiments of the present utility model and features in the embodiments may be combined with each other.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model, however, the present utility model may be practiced otherwise than as described, and therefore the scope of the present utility model is not limited to the specific embodiments disclosed below.

As shown in FIG. 1, the underground heat exchange power generation pipeline comprises a pipeline body 1 and TEG chips 2, wherein the section of the inner wall of the pipeline body 1 is circular, the section of the outer wall of the pipeline body is hexagonal, the TEG chips 2 are uniformly attached to each plane of the outer wall of the pipeline body 1, and each TEG chip 2 is electrically connected. The TEG chips 2 may be connected in series, parallel, or both to regulate the total output voltage and current, and the power of the TEG2 chips may be transmitted to the ground by connecting a total high-temperature and high-voltage resistant cable.

The underground power generation system comprises a pipeline body 1 and a sleeve pipe fitting 6, wherein the pipeline body 1 and the sleeve pipe fitting 6 are arranged in a mode that the pipeline body 1 and the sleeve pipe fitting 6 extend into an underground high-temperature reservoir 13.

Preferably, as shown in fig. 4 and 6, when the sleeve member 6 is disposed outside the pipe body 1, the sleeve member 6 includes a first sleeve member 7 and a second sleeve member 8, the first sleeve member 7 is disposed outside the pipe body 1, a packer 12 is disposed between the first sleeve member 7 and the pipe body 1 to seal the first sleeve member, the second sleeve member 8 is disposed between the pipe body 1 and the first sleeve member 7, and the bottom of the second sleeve member 8 is communicated with the first sleeve member 7. When the power generation system is arranged in a vertical well and used, low-temperature fluid 10 is injected from the second sleeve pipe fitting 8, the low-temperature fluid 10 flows out from the first sleeve pipe fitting 7 due to the arrangement of the packer 12, high-temperature fluid 12 in the high-temperature reservoir 13 flows to a wellhead through the pipeline body 1, and at the moment, temperature difference is generated at two sides of the TEG chip 2 to generate power; when the power generation system is arranged in a horizontal well and used, if hydraulic fracturing does not exist, low-temperature fluid 10 flows into the horizontal well from the second sleeve pipe fitting 8, the low-temperature fluid 10 flows out of the first sleeve pipe fitting 7 due to the arrangement of the packer 12, high-temperature fluid 11 in the high-temperature reservoir 13 flows to a wellhead from the pipeline body 1, and at the moment, temperature difference is generated at two sides of the TEG chip 2 to generate power.

Preferably, as shown in fig. 7, when the power generation system is arranged and used in a horizontal well and the high-permeability pore canal 14 exists, when the sleeve pipe fitting 6 is arranged inside the pipeline body 1, the pipeline body 1 is arranged in the well, a passage is reserved between the pipeline body 1 and the well wall, the bottom of the pipeline body 1 is closed, and the sleeve pipe fitting 6 is arranged inside the pipeline body 1 and the bottom of the sleeve pipe fitting 6 is communicated with the pipeline body 1. The low-temperature fluid 10 flows in from the passage between the sleeve pipe fitting 6 and the pipeline body 1, flows out from the sleeve pipe fitting 6, and the high-temperature fluid 11 in the high-temperature reservoir 13 flows to the wellhead through the passage between the pipeline body 1 and the well wall, and at the moment, the temperature difference is generated at the two sides of the TEG chip 2 so as to generate electricity.

Preferably, the high-temperature reservoir layer 13 outside the well wall is provided with a high-permeability pore canal 14.

As shown in fig. 2 and 3, an underground heat exchange power generation pipeline comprises a pipeline body 1, wherein the pipeline body 1 comprises an oil pipe 3 and a sleeve 4, the oil pipe 3 is arranged in the sleeve 4, the oil pipe 3 is a round pipe, the oil pipe 3 is a conventional oil pipe, the inner wall of the sleeve 4 is round, the outer wall of the sleeve 4 is of an equal hexagon, TEG chips 2 are uniformly distributed on the outer wall of the sleeve 4, the TEG chips 2 are electrically connected in series, in parallel or in series-parallel, the TEG chips 2 can be connected in a mode of adjusting total output voltage and current, and the electric power of the TEG2 chips is transmitted to the ground by connecting a total high-temperature and high-pressure resistant cable. The fin heat exchanger 5 is arranged outside the TEG chip 2, and a larger heat exchange area is obtained through the fin heat exchanger 5, so that the heat transfer efficiency is improved.

As shown in fig. 5 and 8, the downhole power generation system comprises an oil pipe 3 and a casing 4, wherein the casing 4 is attached to a high-temperature reservoir 13, the bottom of the casing 4 is closed, the oil pipe 3 is arranged in the casing 4, an oil casing annulus 9 is formed between the oil pipe 3 and the casing 4, and the bottom of the oil pipe 3 is communicated with the oil casing annulus. The power generation system can be arranged in a vertical well or a horizontal well, low-temperature fluid 10 is injected from an oil sleeve annulus 9 between an oil pipe 3 and a sleeve 4, when the low-temperature fluid 10 moves to the bottom, a high-temperature reservoir 13 is encountered, temperature difference is generated at two sides of a TEG chip 2 so as to generate power, and after the low-temperature fluid 10 is heated by the high-temperature reservoir 13, the low-temperature fluid 10 becomes high-temperature fluid 11 and rises to a wellhead through the oil pipe 3 so as to be utilized.

Preferably, the high-temperature reservoir 13 outside the casing 4 is provided with high-permeability channels 14.

As shown in fig. 9, a U-shaped well downhole power generation system comprises a pipeline body 1, an oil 3 pipe and a sleeve 4,U, wherein the oil 3 pipe and the sleeve 4 are arranged in a vertical shaft section on one side of the U-shaped well, the sleeve 4 is arranged on the outer side of the oil 3 pipe, a packer 12 is arranged between the oil 3 pipe and the sleeve 4 near the position of a high-temperature reservoir 13, the oil pipe 3 is not arranged after entering the high-temperature reservoir 13, the horizontal section of the U-shaped well is only provided with the sleeve 4, a TEG chip 2 is arranged on the side wall of the sleeve 4, near the horizontal section of the U-shaped well, a high-permeability pore canal 14 is formed in a part of the high-temperature reservoir 13 near the horizontal section of the U-shaped well, a pipeline body 1 is arranged in a vertical section on the other side of the U-shaped well, a first sleeve pipe fitting 7 and a second sleeve fitting 8 are arranged on the outer side of the pipeline body 1, the first sleeve fitting 7 and the pipeline body 1 are sealed by the packer 12 arranged at the height of the high-temperature reservoir 13, and the pipeline body 1 extends downwards to be communicated with the sleeve 4 of the horizontal section of the U-shaped well. The low-temperature fluid 10 flows in from the oil pipe 3 at one side, enters the horizontal section of the U-shaped well, flows in the sleeve pipe 4 of the horizontal section, the TEG chip 2 of the horizontal section generates electricity through temperature difference at two sides, the low-temperature fluid 10 becomes the high-temperature fluid 11 after being heated in the high-temperature reservoir 13, the high-temperature fluid 11 rises to a wellhead from the pipeline body 1 of the vertical shaft section at the other side of the U-shaped well, the low-temperature fluid 10 is injected into the second sleeve pipe fitting 8 outside the pipeline body 1 near the wellhead section, the low-temperature fluid flows out after circulating in the first sleeve pipe fitting 7, and the TEG chip 2 arranged outside the pipeline body 1 generates electricity through temperature difference generated inside and outside the pipeline body 1.

The fluid circulated in the well can adopt conventional water or supercritical carbon dioxide to improve the heat exchange speed and heat exchange efficiency from the bottom of the well to the surface, and the thermosiphon effect can be fully utilized to reduce the power of the pumping system even without the pumping system.

The high permeability tunnels 14 may be cracks or tunnels formed by perforation or hydraulic fracturing, and in order to increase the heat transfer rate and efficiency from the thermal reservoir rock to the vicinity of the bottom of the well, a plurality of holes of several meters long are created in the high temperature reservoir 13 rock by perforation, and the space outside the casing 4 and the holes are filled with a material with high heat conductivity or a superconducting material, including a superconducting fluid, to enhance the conduction of thermal energy from the deep thermal reservoir to the bottom of the well and the hot end of the TEG chip 2. Cracks can also be generated by small acidizing or hydraulic fracturing, no earthquake can be generated, and the space outside the sleeve 4 and the cracks are filled with materials with high heat conductivity or superconducting materials.

The ground is provided with a heat energy comprehensive utilization system, which comprises heating, refrigerating and the like; the well structure may be a vertical well, an inclined well, a horizontal well, a lateral well, a fishbone well, a U-shaped well, etc.

The present utility model has been described in detail with reference to the preferred embodiments thereof, but the present utility model is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present utility model, and the present utility model is not limited to the above embodiments.

Claims

1. The utility model provides a heat transfer electricity generation pipeline in pit which characterized in that: the pipeline comprises a pipeline body (1) and TEG chips (2), wherein the section of the inner wall of the pipeline body (1) is circular, the section of the outer wall of the pipeline body is isosceles, the TEG chips (2) are uniformly attached to each plane of the outer wall of the pipeline body (1), and the TEG chips (2) are electrically connected.

2. A downhole heat exchange power generation conduit according to claim 1, wherein: including pipeline body (1), pipeline body (1) includes oil pipe (3) and sleeve pipe (4), oil pipe (3) set up in sleeve pipe (4), oil pipe (3) adopt circular pipe, sleeve pipe (4) inner wall is circular, and the outer wall is the polygon of waiting, sleeve pipe (4) outer wall evenly has laid TEG chip (2), each TEG chip (2) electric connection, TEG chip (2) outside is provided with fin heat exchanger (5).

3. A downhole power generation system utilizing the downhole heat exchange power generation conduit of claim 2, wherein: the oil pipe (3) and the casing (4) as claimed in claim 2, wherein the casing (4) is arranged in a manner of being attached to the high-temperature reservoir (13), the bottom of the casing (4) is closed, the oil pipe (3) is arranged in the casing (4), an oil casing annulus (9) is formed between the oil pipe (3) and the casing (4), and the bottom of the oil pipe (3) is communicated with the oil casing annulus (9).

4. A downhole power generation system according to claim 3, wherein: and a high-permeability pore canal (14) is arranged on the high-temperature reservoir (13) at the outer side of the sleeve (4).

5. A downhole power generation system utilizing the downhole heat exchange power generation conduit of claim 1, wherein: comprising a pipe body (1) and a sleeve pipe fitting (6) as claimed in claim 1, wherein the pipe body (1) and the sleeve pipe fitting (6) are both arranged to extend into a part of a downhole high-temperature reservoir (13), and the sleeve pipe fitting (6) is arranged inside or outside the pipe body (1).

6. The downhole power generation system of claim 5, wherein: when sleeve pipe spare (6) set up in pipeline body (1) outside, sleeve pipe spare (6) are including first sleeve pipe spare (7) and second sleeve pipe spare (8), first sleeve pipe spare (7) set up the outside at pipeline body (1), be provided with packer (12) shutoff between first sleeve pipe spare (7) and pipeline body (1), second sleeve pipe spare (8) set up between pipeline body (1) and first sleeve pipe spare (7), intercommunication between second sleeve pipe spare (8) bottom and first sleeve pipe spare (7).

7. The downhole power generation system of claim 5, wherein: when the sleeve pipe fitting (6) is arranged inside the pipeline body (1), the pipeline body (1) is arranged in a well, a passage is reserved between the pipeline body (1) and a well wall, the bottom of the pipeline body (1) is closed, and the sleeve pipe fitting (6) is arranged in the pipeline body (1) and is communicated with the pipeline body (1) at the bottom.

8. A downhole power generation system according to claim 7, wherein: high-permeability pore channels (14) are arranged on the high-temperature reservoir (13) at the outer side of the well wall.