Open type middle-deep layer heat exchange well device

Abstract

The utility model relates to the technical field of middle-deep layer heat exchange well devices, in particular to an open type middle-deep layer heat exchange well device which comprises a well wall pipe. The central pipe is installed in the well wall pipe, the water filtering pipe is installed on the well wall pipe, and a heat exchange runner is formed between the well wall pipe and the central pipe; the casing pipe is located in the heat exchange well and penetrates through the water-containing stratum to stretch into the rock heat type heat reservoir, and a first annular gap is formed between the outer wall, located in the rock heat type heat reservoir, of the casing pipe and the inner wall of the rock heat type heat reservoir. The water filtering pipe comprises an upper water filtering pipe and a lower water filtering pipe, the upper water filtering pipe is located in the middle of the casing pipe, and the lower water filtering pipe is located at the bottom of the casing pipe or close to the bottom; according to the device, the positions of the upper water filter pipe, the lower water filter pipe and the water stop device are reasonably arranged, so that a heat exchange medium can be in direct contact with a rock heat type heat reservoir, the mineral content in the heat exchange medium is increased, and rock heat type geothermal resources are suitable for hot spring bathing; meanwhile, the heat exchange efficiency of the heat exchange well is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of medium - deep heat exchange well devices, in particular to an open - type medium - deep heat exchange well device applied to the development and utilization of rock - type geothermal resources. Background Art

[0002] In a medium - deep heat exchange well, heat is carried from a geothermal reservoir to the ground by a fluid medium for heat exchange and utilization. In the existing medium - deep heat exchange well technology, low - temperature water is injected into the medium - deep heat exchange well from an inlet pipe, and heat exchange is completed with the heat reservoir through a well - wall pipe in the heat exchange well, and then flows out of the heat exchange well through a central pipe. Due to the barrier of the well - wall pipe, the fluid medium cannot directly contact the heat - reservoir rock. On the one hand, the heat - exchange area is reduced, resulting in a decrease in heat - exchange efficiency; on the other hand, the fluid medium does not contact the rock and cannot dissolve the beneficial minerals in the rock, failing to meet the water - quality requirements for hot - spring bathing.

[0003] Therefore, it is necessary to design a medium - deep heat exchange well device to improve the above problems. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the defects of the prior art and provide an open - type medium - deep heat exchange well device.

[0005] The utility model provides an open - type medium - deep heat exchange well device, which includes a well - wall pipe; a central pipe installed in the well - wall pipe and a filter pipe installed on the well - wall pipe. A heat - exchange flow channel is formed between the well - wall pipe and the central pipe;

[0006] The well - wall pipe is located in the heat exchange well and penetrates through an aquiferous formation and extends into a rock - type heat reservoir. A first annular gap is formed between the outer wall of the well - wall pipe located in the rock - type heat reservoir and the inner wall of the rock - type heat reservoir;

[0007] The filter pipe includes an upper filter pipe and a lower filter pipe. The upper filter pipe is located in the middle of the well - wall pipe, and the lower filter pipe is located at the bottom or near the bottom of the well - wall pipe, and is used to connect the heat - exchange channel and the first annular gap to realize direct - contact heat exchange between the heat - exchange medium and the rock - type heat reservoir.

[0008] Further, a first water - stop member is arranged between the aquiferous formation and the rock - type heat reservoir, and the first water - stop member is located above the upper filter pipe.

[0009] Further, a second water - stop member is arranged in the heat - exchange flow channel, and the second water - stop member is located below the upper filter pipe.

[0010] Further, a third water - stop member is arranged in the heat - exchange flow channel, and the third water - stop member is located above the lower filter pipe.

[0011] Furthermore, a sealing and water-stop member is provided between the outer wall of the well casing pipe and the inner wall of the heat exchange well, and the sealing and water-stop member is located in the water-bearing formation.

[0012] Furthermore, the central pipe is a heat-insulating pipe, and a gap is provided between the bottom of the central pipe and the bottom of the heat exchange well for the heat exchange medium to flow through the lower filter pipe and into the central pipe.

[0013] Furthermore, the top of the central pipe is connected with a first pipeline for discharging the heat exchange medium in the rock heat type heat storage layer from the first pipeline.

[0014] Furthermore, a second pipeline is installed on one side of the top of the well casing pipe, and an exhaust pipe is installed on the other side of the well casing pipe.

[0015] Furthermore, a gate is installed on the exhaust pipe for regulating the discharge of gas;

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] The device of the present utility model is used for the development and utilization of rock heat type geothermal resources. A central pipe is installed in the well casing pipe, and a filter pipe is installed on the well casing pipe. The upper filter pipe of the filter pipe is located in the middle of the well casing pipe, and the lower filter pipe is located at the bottom or near the bottom of the well casing pipe for communicating the heat exchange channel and the first annular gap to realize direct contact heat exchange between the heat exchange medium and the rock heat type heat storage layer; a first water-stop member is provided between the water-bearing formation and the rock heat type heat storage layer, and the first water-stop member is located above the upper filter pipe; a second water-stop member is provided in the heat exchange flow channel, and the second water-stop member is located below the upper filter pipe; a third water-stop member is provided in the heat exchange flow channel, and the third water-stop member is located above the lower filter pipe; by reasonably installing the upper filter pipe, the lower filter pipe and the water-stop device, the heat exchange medium can directly contact the rock heat type heat storage layer. On the one hand, the heat exchange medium can undergo a water-rock reaction with the heat storage layer rock, increasing the mineral content in the heat exchange medium and making the rock heat type geothermal resources suitable for hot spring bathing; on the other hand, the heat exchange medium can directly absorb the heat of the rock heat type heat storage layer, improving the heat exchange efficiency of the heat exchange well and meeting the water temperature requirements for hot spring bathing water. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The following drawings are only schematic illustrations and explanations of the present utility model and are not used to limit the scope of the present utility model, wherein:

[0019] Figure 1 : Structural schematic diagram of the open type medium and deep layer heat exchange well device of the present utility model;

[0020] In the figure: 1 - well casing pipe; 2 - filter pipe; 3 - water-stop device; 4 - central pipe; 5 - cement; 6 - second pipeline; 7 - first pipeline; 8 - exhaust pipe; 9 - water-bearing formation; 10 - rock heat type heat storage layer; 11 - first annular gap. Specific embodiments

[0021] In order to make the objectives, technical solutions, design methods, and advantages of the present utility model clearer, the present utility model will be further described in detail below through specific embodiments in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0022] As Figure 1 shown, the present utility model provides an open-type medium-deep heat exchange well device,

[0023] including a well casing 1;

[0024] a central pipe 4 installed inside the well casing 1 and a filter pipe 2 installed on the well casing 1. A heat exchange flow channel is formed between the well casing 1 and the central pipe 4;

[0025] The well casing 1 is located inside the heat exchange well and penetrates through the water-bearing formation 9 and extends into the rock heat type heat reservoir 10. A first annular gap 11 is formed between the outer wall of the well casing 1 located in the rock heat type heat reservoir 10 and the inner wall of the rock heat type heat reservoir 10;

[0026] The filter pipe 2 includes an upper filter pipe and a lower filter pipe. The upper filter pipe is located in the middle of the well casing 1, and the lower filter pipe is located at the bottom or near the bottom of the well casing 1, and is used to connect the heat exchange channel and the first annular gap 11 to realize direct contact heat exchange between the heat exchange medium and the rock heat type heat reservoir 10;

[0027] Wherein, a first water stop member is provided between the water-bearing formation 9 and the rock heat type heat reservoir 10, and the first water stop member is located above the upper filter pipe; a second water stop member is provided in the heat exchange flow channel, and the second water stop member is located below the upper filter pipe; a third water stop member is provided in the heat exchange flow channel, and the third water stop member is located above the lower filter pipe; a sealing water stop member is provided between the outer wall of the well casing 1 and the inner wall of the heat exchange well, and the sealing water stop member is located in the water-bearing formation 9; the sealing water stop member is cement 5; by reasonably installing the positions of the upper filter pipe, the lower filter pipe, and the water stop 3, the heat exchange medium can directly contact the rock heat type heat reservoir. On the one hand, the water medium can undergo a water-rock reaction with the heat reservoir rock, adding some beneficial mineral components to the water to become hot mineral water, meeting the requirements for hot spring bath water; on the other hand, the water medium can directly absorb the heat of the rock heat type heat reservoir, reducing the thermal resistance of the first annular gap, and at the same time increasing the heat exchange area between the water medium and the heat reservoir, improving the heat exchange efficiency of the heat exchange well, and meeting the water temperature requirements for hot spring bath water;

[0028] Wherein, the central pipe 4 is a heat-insulating pipe, and a gap is provided between the bottom of the central pipe 4 and the bottom of the heat exchange well for the heat exchange medium to flow through the lower filter pipe and into the central pipe 4;

[0029] Among them, a first pipeline 7 is connected to the top of the central pipe 4 for discharging the heat exchange medium in the rock thermal reservoir 10 from the first pipeline 7; the central pipe 4 is made of polypropylene or a double-layer vacuum heat-insulating pipe, which has a heat-insulating effect. After the heat exchange medium absorbs heat, it flows out of the heat exchange well from the inside of the central pipe 4, reducing heat loss; among them, after heat exchange through the second pipeline 6 and the central pipe 4, the water is discharged from the first pipeline 7.

[0030] Among them, a second pipeline 6 is installed on one side of the top of the wellbore pipe 1, and an exhaust pipe 8 is installed on the other side of the wellbore pipe 1; a gate is installed on the exhaust pipe 8 for regulating the discharge of gas; the exhaust pipe 8 is used to discharge air or other non-condensable gases in the wellbore pipe 1 to prevent them from causing adverse effects on the wellbore pipe 1, such as reducing the thermal efficiency and intensifying corrosion.

[0031] It should be noted that the open medium-deep heat exchange well device in this application is used for the development and utilization of rock thermal geothermal resources; a central pipe is installed in the wellbore pipe 1, and a filter water pipe 2 is installed on the wellbore pipe 1. The upper filter water pipe of the filter water pipe 2 is located in the middle of the wellbore pipe 1, and the lower filter water pipe is located at the bottom or near the bottom of the wellbore pipe 1, which is used to connect the heat exchange channel and the first annular gap 11 to realize direct contact heat exchange between the heat exchange medium and the rock thermal reservoir 10; a first water stop member is arranged between the water-bearing formation 9 and the rock thermal reservoir 10, and the first water stop member is located above the upper filter water pipe, the second water stop member 3 is located below the upper filter water pipe, and the third water stop member is located above the lower filter water pipe. The first water stop member, the second water stop member and the third water stop member are all water stoppers. By reasonably installing the positions of the upper filter water pipe, the lower filter water pipe and the water stopper, the heat exchange medium can directly contact the rock thermal reservoir. On the one hand, the water medium can undergo a water-rock reaction with the reservoir rock, adding some beneficial mineral components to the water to become hot mineral water, meeting the water temperature requirements for hot spring bathing; on the other hand, the water medium can directly absorb the heat of the rock thermal reservoir, reducing the thermal resistance of the first annular gap, and at the same time increasing the heat exchange area between the water medium and the reservoir, improving the heat exchange efficiency of the heat exchange well and meeting the water temperature requirements for hot spring bathing.

[0032] The above has described the embodiments of the present invention. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skill in the art in the technical field to understand the disclosed embodiments.

Claims

1. An open medium-deep heat exchange well device, characterized in that: It comprises a well wall pipe (1); a central pipe (4) installed in the well wall pipe (1); and a water filter pipe (2) installed on the well wall pipe (1); a heat exchange channel is formed between the well wall pipe (1) and the central pipe (4); The wellbore pipe (1) is located in the heat exchange well and extends through the water-bearing stratum (9) into the rock thermal heat reservoir (10). A first annular gap (11) is formed between the outer wall of the wellbore pipe (1) located in the rock thermal heat reservoir (10) and the inner wall of the rock thermal heat reservoir (10); The water filter pipe (2) comprises an upper water filter pipe and a lower water filter pipe, wherein the upper water filter pipe is located in the middle of the well wall pipe (1), and the lower water filter pipe is located at the bottom of the well wall pipe (1) or near the bottom, and is used to connect the heat exchange channel and the first annular gap (11) to achieve direct contact heat exchange between the heat exchange medium and the rock thermal type heat reservoir (10).

2. An open medium-deep heat exchange well device according to claim 1, characterized in that: A first water stop is provided between the water-bearing stratum (9) and the rock-thermal heat reservoir (10), and the first water stop is located above the upper water filter pipe.

3. The open medium-deep heat exchange well device according to claim 1, characterized in that: A second water stop is provided in the heat exchange flow channel, and the second water stop is located below the upper water filter pipe.

4. The open medium-deep heat exchange well device according to claim 1, characterized in that: A third water stop is arranged in the heat exchange flow channel, and the third water stop is located above the lower water filter pipe.

5. The open medium-deep heat exchange well device according to claim 1, characterized in that: A sealing water-stopping member is provided between the outer wall of the well wall pipe (1) and the inner wall of the heat exchange well, and the sealing water-stopping member is located in the water-bearing stratum (9).

6. The open medium-deep heat exchange well device according to claim 1, characterized in that: The central tube (4) is a heat-insulating tube, and a gap is provided between the bottom of the central tube (4) and the bottom of the heat exchange well, for the heat exchange medium to pass through the lower filter tube and flow into the central tube (4).

7. The open medium-deep heat exchange well device according to claim 1, characterized in that: The top of the central tube (4) is connected to a first pipeline (7) for discharging the heat exchange medium in the rock thermal reservoir (10) from the first pipeline (7).

8. The open medium-deep heat exchange well device according to claim 1, characterized in that: A second pipeline (6) is installed on one side of the top of the well wall pipe (1), and an exhaust pipe (8) is installed on the other side of the well wall pipe (1).

9. An open medium-deep heat exchange well device according to claim 8, characterized in that: The exhaust pipe (8) is provided with a gate for regulating the discharge of gas.

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