Thermal insulation pipe structure of geothermal well

Abstract

The utility model discloses a geothermal well thermal insulation pipe structure which comprises an outer layer pipe, an inner layer pipe is further arranged in the outer layer pipe, the outer layer pipe clamps the inner layer pipe through a plurality of fixing assemblies, and the inner layer pipe and the outer layer pipe are coaxially arranged. The fixing assembly comprises a first fixing plate and a second fixing plate, the first fixing plate is fixed to the inner wall of the outer layer pipe, fixing grooves are formed in the two ends of the arc-shaped first fixing plate, fixing blocks are arranged at the two ends of the arc-shaped second fixing plate, and the fixing blocks are clamped in the fixing grooves. The inner-layer pipe and the outer-layer pipe are arranged at the same time, heat loss is effectively reduced through the double-layer pipeline, the transmission efficiency of geothermal energy is improved, energy waste is reduced, the safety of the pipeline can be improved through the design of the double-layer pipeline, and the operation risk of a geothermal well system is reduced; the inner-layer pipe is supported through the first fixing plate and the second fixing plate, so that the structure of the heat preservation pipe is more stable, extrusion and deformation of fluid media inside and outside the heat preservation pipe can be borne, and the risk of pipeline breakage is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of geothermal wells, in particular to a geothermal well insulation pipe structure. Background Art

[0002] Geothermal energy is a type of clean energy. The medium-deep non-interference geothermal technology, which is characterized by "closed heat exchange in the well, heat extraction without water", is a non-hydrothermal extraction method that is currently widely used. It uses mechanical drilling methods to drill to a certain depth underground, inject softened water as a circulating working fluid into the heat exchanger, and extract the heat energy in the rock and soil layer through heat conduction. In the heat extraction process, the hot water in the heat supply pipeline on the heat source side exchanges heat with the cold water in the annulus, and then is transported back to the geothermal well through the return water pipeline on the heat source side. However, the current return water pipeline on the heat source side mainly uses plastic single pipes made of PE (polyethylene), PE-RT (heat-resistant polyethylene) and other materials, resulting in a large loss of heat along the way in the water medium in the return water pipeline on the heat source side, which in turn leads to a low return water temperature at the wellhead, affecting the heat extraction efficiency of shallow or medium-deep geothermal wells. Utility Model Content

[0003] The utility model aims to provide a geothermal well insulation pipe structure, which is used to solve the problem of large heat loss along the way during water medium transportation in the prior art mentioned in the above background technology.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] A geothermal well insulation pipe structure comprises an outer layer pipe, an inner layer pipe is arranged inside the outer layer pipe, the outer layer pipe clamps the inner layer pipe through a plurality of fixing components, and the inner layer pipe and the outer layer pipe are coaxially arranged.

[0006] Furthermore, the fixing assembly includes a first fixing plate and a second fixing plate. The first fixing plate is fixed to the inner wall of the outer tube. Both ends of the arc-shaped first fixing plate are provided with fixing grooves. Both ends of the arc-shaped second fixing plate are provided with fixing blocks, which are clamped in the fixing grooves.

[0007] Furthermore, a movable bin connected to the fixed groove is provided on the outside of the fixed groove, the outer wall of the movable bin is fixedly connected to the outer layer tube, the first rotating shaft is rotatably installed on the top wall of the movable bin, the upper end of the first rotating shaft is connected to the knob, and the lower end thereof is connected to the first bevel gear, the knob is located outside the movable bin, and the second rotating shaft is rotatably installed on the inner wall of the movable bin, and the second rotating shaft is installed with a second bevel gear meshing with the first bevel gear; the surface of the second rotating shaft is provided with a thread, and the second rotating shaft is threadedly connected to a threaded tube, one end of the threaded tube is inserted into the fixed groove and then connected to a limit block, and one end of the limit block is clamped in the limit groove opened on the surface of the fixed block.

[0008] Furthermore, a sliding block is provided on the outer side surface of the threaded tube, and the sliding block is slidably connected to a sliding groove provided on the surface of the movable bin.

[0009] Preferably, there are two sliders, which are symmetrically arranged on the outer side of the threaded tube.

[0010] Furthermore, the outer wall of the outer layer tube is sprayed with a wear-resistant layer, and the inner wall thereof is coated with a heat-insulating coating.

[0011] Preferably, the outer tube is made of steel, the wear-resistant layer sprayed on the outer wall is a nickel-aluminum alloy layer, and the heat-insulating coating coated on the inner wall is a zirconium oxide coating.

[0012] Furthermore, the inner wall of the inner tube is coated with a hydrophobic coating, and the outer wall thereof is sprayed with a heat-insulating coating.

[0013] Preferably, the inner tube is made of steel, the thermal insulation coating sprayed on the outer wall is a zirconium oxide coating, and the hydrophobic coating sprayed on the inner wall is a polytetrafluoroethylene hydrophobic coating.

[0014] Furthermore, the space between the inner tube and the outer tube is filled with thermal insulation material.

[0015] Preferably, the thermal insulation material has a density of 400 kg / m 3 Medium to high density rigid polyurethane with a density of ~600kg / m3.

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

[0017] 1. The utility model is provided with an inner layer tube and an outer layer tube at the same time. The double-layer tube effectively reduces heat loss, improves the transmission efficiency of geothermal energy, reduces energy waste, and the double-layer tube design can improve the safety of the tube and reduce the operating risk of the geothermal well system. The inner layer tube is supported by the first fixed plate and the second fixed plate, so that the structure of the insulation tube is more stable, can withstand the extrusion and deformation of the fluid medium inside and outside the insulation tube, and reduce the risk of pipeline rupture.

[0018] 2. The utility model can fine-tune the first fixing plate and the second fixing plate according to the specific diameter of the inner tube through the fixing components, so that the first fixing plate and the second fixing plate can fit the inner tube, thereby clamping and supporting the inner tube. Multiple fixing components can greatly improve the compressive strength of the inner tube and prevent the inner tube from rupture and deformation due to outer wall pressure.

[0019] 3. The utility model coats a wear-resistant layer on the outer wall of the outer tube to improve the wear resistance, corrosion resistance, high temperature resistance and oxidation resistance of the thermal insulation pipe, and sprays a hydrophobic coating on the inner wall of the inner tube, which can greatly improve the hydrophobicity of the inner tube, thereby reducing the residence time of the hot water medium on the inner wall of the inner tube, thereby reducing heat loss and scale formation, and increasing its service life; coating a thermal insulation coating on the inner wall of the outer tube and the outer wall of the inner tube can greatly improve the thermal insulation performance, high thermal stability, and corrosion resistance of the thermal insulation pipe.

[0020] 4. The utility model fills the space between the outer layer pipe and the inner layer pipe with high-strength thermal insulation material, so that the utility model has good resistance to deep water pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a three-dimensional structural schematic diagram of the utility model;

[0022] Figure 2 It is a front view cross-sectional structural schematic diagram of the utility model;

[0023] Figure 3 for Figure 2 A partial enlarged view of the middle part;

[0024] In the figure: 1-outer tube, 2-inner tube, 3-fixed component, 301-first fixed plate, 3011-movable bin, 3012-fixed groove, 302-second fixed plate, 3021-fixed block, 3022-limiting groove, 303-first rotating shaft, 3031-knob, 304-first bevel gear, 305-second rotating shaft, 306-second bevel gear, 307-threaded tube, 3071-slider, 308-limiting block. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0026] See also Figure 1-3 The utility model provides a geothermal well insulation pipe structure, including an outer layer pipe 1, an inner layer pipe 2 is also arranged inside the outer layer pipe 1, the outer layer pipe 1 clamps the inner layer pipe 2 through a plurality of fixing components 3, and the inner layer pipe 2 and the outer layer pipe 1 are coaxially arranged.

[0027] The utility model forms a double-layer pipe structure by setting an inner pipe 2 and an outer pipe 1, which effectively reduces heat loss, improves the transmission efficiency of geothermal energy, and reduces energy waste. In addition, the double-layer pipe design can improve the safety of the pipe and reduce the operating risk of the geothermal well system.

[0028] Specifically, the fixing assembly 3 includes a first fixing plate 301 and a second fixing plate 302. The first fixing plate 301 is fixed to the inner wall of the outer tube 1. Fixing grooves 3012 are provided at both ends of the arc-shaped first fixing plate 301. Fixing blocks 3021 are provided at both ends of the arc-shaped second fixing plate 302. The fixing blocks 3021 are clamped in the fixing grooves 3012.

[0029] The utility model can clamp and support the inner layer pipe 2 by setting the first fixing plate 301 and the second fixing plate 302, so that the structure of the insulation pipe is more stable, can withstand the extrusion and deformation of the complex underground environment, and reduce the risk of pipeline rupture.

[0030] Specifically, a movable bin 3011 connected to the fixed groove 3012 is arranged outside the movable groove 3012, and the outer wall of the movable bin 3011 is fixedly connected to the outer tube 1. The first rotating shaft 303 is rotatably installed on the top wall of the movable bin 3011. The upper end of the first rotating shaft 303 is connected to the knob 3031, and the lower end thereof is connected to the first bevel gear 304. The knob 3031 is located outside the movable bin 3011. The inner wall of the movable bin 3011 is rotatably installed with a second rotating shaft 305, and a gear connected to the first bevel gear is installed on the second rotating shaft 305. 304 is meshed with a second bevel gear 306; the surface of the second rotating shaft 305 is provided with a thread, the second rotating shaft 305 is threadedly connected with a threaded tube 307, one end of the threaded tube 307 is inserted into the fixed groove 3012 and then connected to a limit block 308, one end of the limit block 308 is clamped in the limit groove 3022 opened on the surface of the fixed block 3021; ​​a slider 3071 is set on the outer side of the threaded tube 307, and the slider 3071 is slidably connected to the slide groove opened on the surface of the movable warehouse 3011.

[0031] In a preferred embodiment, there are two sliders 3071 , which are symmetrically arranged on the outer side of the threaded tube 307 , and there are also two slide grooves matching the sliders 3071 .

[0032] The utility model can fine-tune the first fixing plate 301 and the second fixing plate 302 according to the specific diameter of the inner tube 2 through the fixing component 3, so that the first fixing plate 301 and the second fixing plate 302 can fit the inner tube 2, thereby clamping and supporting the inner tube 2 and improving the pressure resistance of the inner tube 2. Multiple fixing components 3 can greatly improve the compressive strength of the inner tube 2 and prevent the inner tube 2 from rupture and deformation due to the pressure of the outer wall.

[0033] Specifically, the outer wall of the outer layer tube 1 is sprayed with a wear-resistant layer, and the inner wall thereof is coated with a heat-insulating coating.

[0034] In a preferred embodiment, the outer tube 1 is made of steel, the wear-resistant layer sprayed on the outer wall is a nickel-aluminum alloy layer, and the thermal insulation coating coated on the inner wall is a zirconium oxide coating. The nickel-aluminum alloy layer is coated on the outer wall of the outer tube 1 by plasma spraying technology, and the obtained coating is dense and uniform, and the bonding strength between the coating and the outer tube 1 is good. The nickel-aluminum alloy coating has good wear resistance, corrosion resistance, high temperature performance and oxidation resistance; the zirconium oxide coating is coated on the inner wall of the outer tube 1 by chemical vapor deposition, which can make the outer tube 1 have excellent thermal insulation performance, high thermal stability, and corrosion resistance.

[0035] Specifically, the inner wall of the inner layer tube 2 is coated with a hydrophobic coating, and the outer wall thereof is sprayed with a heat insulation coating.

[0036] In a preferred embodiment, the inner tube 2 is made of steel, the thermal insulation coating sprayed on its outer wall is a zirconium oxide coating, and the hydrophobic coating sprayed on its inner wall is a polytetrafluoroethylene hydrophobic coating. By coating the zirconium oxide coating on the outer wall of the inner tube 2 by chemical vapor deposition, the inner tube 2 can have excellent thermal insulation performance, high thermal stability, and corrosion resistance; by coating the polytetrafluoroethylene hydrophobic coating on the inner wall of the inner tube 2, the hydrophobicity of the inner tube 2 can be greatly improved, thereby reducing the residence time of the hot water medium on the inner wall of the inner tube 2, thereby reducing heat loss and scale formation, and improving its service life.

[0037] Specifically, the space between the inner tube 2 and the outer tube 1 is filled with thermal insulation material.

[0038] In a preferred embodiment, the thermal insulation material has a density of 400 kg / m 3 ~600kg / m 3 The medium and high density hard polyurethane makes the compressive strength of the geothermal well insulation pipe of the utility model reach 10MPa-15MPa, and the heat transfer coefficient reaches below 0.10W / (㎡·K), so that it has good water pressure resistance and thermal insulation.

[0039] Based on the embodiments of the present utility model, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present utility model.

Claims

1. A geothermal well insulation pipe structure, comprising an outer layer pipe, characterized in that: An inner tube is also arranged inside the outer tube, and the outer tube clamps the inner tube through a plurality of fixing components, and the inner tube and the outer tube are coaxially arranged; The fixing assembly includes a first fixing plate and a second fixing plate. The first fixing plate is fixed to the inner wall of the outer tube. Both ends of the arc-shaped first fixing plate are provided with fixing grooves. Both ends of the arc-shaped second fixing plate are provided with fixing blocks, which are clamped in the fixing grooves.

2. A geothermal well insulation pipe structure according to claim 1, characterized in that: A movable bin connected to the fixed groove is arranged on the outside of the movable bin, the outer wall of the movable bin is fixedly connected to the outer tube, the first rotating shaft is rotatably installed on the top wall of the movable bin, the upper end of the first rotating shaft is connected to the knob, and the lower end thereof is connected to the first bevel gear, the knob is located outside the movable bin, the second rotating shaft is rotatably installed on the inner wall of the movable bin, and the second bevel gear meshing with the first bevel gear is installed on the second rotating shaft; the surface of the second rotating shaft is provided with a thread, the thread on the second rotating shaft is connected to a threaded tube, one end of the threaded tube is inserted into the fixed groove and then connected to a limit block, and one end of the limit block is clamped in the limit groove opened on the surface of the fixed block.

3. A geothermal well insulation pipe structure according to claim 2, characterized in that: A sliding block is arranged on the outer side of the threaded tube, and the sliding block is slidably connected to a sliding groove provided on the surface of the movable bin.

4. A geothermal well insulation pipe structure according to claim 3, characterized in that: There are two sliders, which are symmetrically arranged on the outer side of the threaded tube.

5. The geothermal well insulation pipe structure according to claim 1, characterized in that: The outer wall of the outer layer pipe is sprayed with a wear-resistant layer, and the inner wall thereof is coated with a heat insulation coating.

6. A geothermal well insulation pipe structure according to claim 5, characterized in that: The outer tube is made of steel, the wear-resistant layer sprayed on the outer wall is a nickel-aluminum alloy layer, and the heat-insulating coating coated on the inner wall is a zirconium oxide coating.

7. A geothermal well insulation pipe structure according to claim 1, characterized in that: The inner wall of the inner tube is coated with a hydrophobic coating, and the outer wall thereof is sprayed with a heat insulation coating.

8. A geothermal well insulation pipe structure according to claim 7, characterized in that: The inner tube is made of steel, the heat-insulating coating sprayed on the outer wall is a zirconium oxide coating, and the hydrophobic coating sprayed on the inner wall is a polytetrafluoroethylene hydrophobic coating.

9. A geothermal well insulation pipe structure according to claim 1, characterized in that: The space between the inner tube and the outer tube is filled with heat-insulating material.

10. A geothermal well insulation pipe structure according to claim 9, characterized in that: The thermal insulation material is medium-high density hard polyurethane with a density of 400kg / m3 to 600kg / m3.

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