Double-layer pipeline shield tunnel prefabricated segments for collecting geothermal energy

Abstract

The present invention discloses a double-layer pipeline shield tunnel prefabricated pipe segment capable of collecting geothermal energy, wherein a plurality of prefabricated component blocks are spliced ​​with each other through facing end faces to form an annular pipe segment body; a double-layer heat exchange pipe, namely an outer pipe and an inner pipe, is arranged in the steel cage of each prefabricated component block, close to the outer wall and inner wall of the corresponding shield tunnel respectively; grooves are arranged at both ends of each prefabricated component block, corresponding to the position of the inner wall of the corresponding shield tunnel; both ends of each heat exchange pipe are exposed at the corresponding groove position in a structure perpendicular to the corresponding end face; a plurality of inner pipes in a plurality of prefabricated component blocks of each pipe segment body, and a plurality of outer pipes are connected end to end in sequence to form an inner and outer ring heat exchange unit, and are connected to a heat pump through a water supply pipe and a return pipe, so as to form a circulation of a heat-carrying fluid in the pipe segment of the shield tunnel. The present invention realizes heat exchange between the heat-carrying fluid and the pipe segment by directly arranging the heat exchange pipe in the pipe segment of the shield or TBM tunnel.

Description

Technical Field

[0001] The invention relates to the technical field of prefabricated segments for shield tunnels, and in particular to a double-layer pipeline prefabricated segment for shield tunnels capable of collecting geothermal energy. Background Art

[0002] The world is facing severe challenges such as environmental destruction and climate change. Energy demand is becoming a constraint on the development of human society. Researchers from all over the world are working hard to find renewable energy sources that can replace fossil fuels.

[0003] Compared with the traditional drilling geothermal mining method, the use of underground structures for geothermal energy mining can achieve the exchange of ground heat and stratum heat while ensuring the mechanical function of the main structure. Deep foundations, shallow foundations, underground continuous walls, tunnel linings and anchors are all energy underground structures that can be used for geothermal energy collection. Compared with other energy underground structures, energy tunnels have a larger structure-soil contact surface that can be used for heat exchange, and have the advantages of good heat transfer effect, high heat exchange efficiency, small footprint and low construction cost.

[0004] Therefore, how to achieve heat exchange between the heat-carrying fluid and the tube sheet, and connect the heat-carrying fluid to the heat pump to achieve the function of heating in winter or cooling in summer has become a technical problem that technicians in this field need to solve urgently. Summary of the invention

[0005] In view of the above-mentioned defects of the prior art, the present invention provides a double-layer pipeline shield tunnel prefabricated segment that can collect geothermal energy. The purpose is to realize heat exchange between the heat-carrying fluid and the segment by circulating the heat-carrying fluid in the heat exchange pipeline inside the shield segment, and connect the heat-carrying fluid to the heat pump to achieve the effect of heating in winter or cooling in summer.

[0006] To achieve the above-mentioned purpose, the present invention discloses a double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy, comprising a universal annular segment body;

[0007] The plurality of segment bodies are sequentially spliced ​​end to end along the axial direction to form a shield tunnel segment;

[0008] Each of the segment bodies comprises a plurality of prefabricated component blocks with fan-shaped longitudinal sections;

[0009] A plurality of the prefabricated component blocks are connected to each other through the facing end surfaces of every two adjacent prefabricated component blocks to form the annular segment body.

[0010] Wherein, the steel cage of each prefabricated component block is provided with double-layer heat exchange pipelines respectively close to the outer wall and the inner wall of the corresponding shield tunnel;

[0011] In the double-layer heat exchange pipeline of each prefabricated component block, the heat exchange pipeline close to the outer wall of the corresponding shield tunnel is the outer pipeline, and the heat exchange pipeline close to the inner wall of the corresponding shield tunnel is the inner pipeline;

[0012] Both ends of each of the prefabricated component blocks are provided with grooves corresponding to the positions of the inner walls of the corresponding shield tunnels;

[0013] Both ends of each heat exchange pipeline in each prefabricated component block are exposed at the corresponding groove position in a structure perpendicular to the corresponding end surface;

[0014] The plurality of inner pipelines in the plurality of prefabricated component blocks of each of the tube segment bodies and the plurality of outer pipelines are sequentially connected end to end to form an inner and outer two-ring heat exchange unit;

[0015] Each heat exchange unit is connected to the water supply pipe and the return pipe at its head end and tail end respectively, either alone or in series with other adjacent heat exchange units;

[0016] The water supply pipe and the return pipe are connected to a heat pump to form a circulation of heat-carrying fluid in the shield tunnel segment.

[0017] Preferably, the plurality of prefabricated component blocks are divided into standard blocks, adjacent blocks and capping blocks in descending order according to the size of the central angle of the corresponding segment body;

[0018] When the arc length of any capping block is insufficient for the corresponding heat exchange pipeline to bend back in the corresponding steel cage, a connecting pipe for connecting the heat exchange pipelines in two adjacent prefabricated component blocks is arranged in the steel cage of the capping block with insufficient arc length.

[0019] Preferably, each of the grooves is arranged at a middle position of an edge formed by the end surface and the concave arc surface of the corresponding prefabricated component block.

[0020] Preferably, the outer pipeline of each prefabricated component block starts from the last bend structure close to the two end positions and moves toward the corresponding inner arc surface of the shield tunnel, and emerges from the corresponding groove in a relative position parallel to the corresponding inner pipeline.

[0021] Preferably, the plurality of prefabricated component blocks connected end to end in each ring of the heat exchange unit are connected via linear joints arranged in the corresponding two assembled grooves.

[0022] Preferably, the flow directions of the heat-carrying fluid in the heat exchange unit in the two rings corresponding to every two adjacent tube sheet bodies are opposite.

[0023] Preferably, the water supply pipe and the return pipe are respectively connected to the head end and tail end of each heat exchange unit, or the head end and tail end of multiple heat exchange units connected in series, through a plurality of transition pipelines;

[0024] Each transition pipe has one end connected to the water supply pipe or the return pipe with a three-way joint, and one end connected to the head end or tail end of each heat exchange unit, or the head end or tail end of multiple heat exchange units connected in series with a right-angle elbow.

[0025] More preferably, each of the three-way connectors is provided with a valve.

[0026] Preferably, the layout direction of each of the heat exchange pipelines is parallel to the axial direction or tangential direction of the corresponding shield tunnel segment.

[0027] Preferably, the water supply pipe and the return pipe are both arranged near the bottom of the shield tunnel segment, that is, the lower half of the corresponding tunnel.

[0028] Beneficial effects of the present invention:

[0029] The present invention directly arranges the heat exchange pipeline in the shield or TBM tunnel segment, does not need to build a separate underground heat extraction structure, and can save costs.

[0030] In the present invention, the heat exchange pipeline can be laid out when the pipe segment is cast. During the tunnel excavation process, only the ports of the heat exchange pipeline need to be connected, which reduces the construction workload and does not conflict with the tunnel excavation process, thereby not delaying the construction period.

[0031] Compared with energy foundations such as energy piles and energy underground continuous walls, the energy tunnel of the present invention has a larger heat exchange area and can collect more heat.

[0032] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of a prefabricated energy pipe segment heat exchange pipeline for geothermal energy collection according to an embodiment of the present invention is shown.

[0034] Figure 2 A schematic diagram of a single pipe segment in a double-layer pipeline layout according to an embodiment of the present invention is shown.

[0035] Figure 3 A schematic diagram of a single pipe segment in which the pipeline direction is parallel to the tunnel direction in the case of single-layer pipeline layout in one embodiment of the present invention is shown.

[0036] Figure 4A schematic diagram of a single pipe segment in which the pipeline direction is perpendicular to the tunnel direction in the case of single-layer pipeline layout in one embodiment of the present invention is shown.

[0037] In the figure: 1 is a standard tube segment, 2 is an adjacent tube segment, 3 is a capped tube segment, 4 is a heat exchange pipeline, 401 is an outer pipeline, 402 is an inner pipeline, 5 is a water supply pipe, 6 is a return pipe, 7 is a tee joint, 8 is a straight joint, 9 is a right-angle elbow, 10 is a groove, and 11 is a transition pipe. DETAILED DESCRIPTION

[0038] like Figures 1 to 4 As shown, a double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy comprises a universal annular segment body;

[0039] The main bodies of multiple segments are spliced ​​end to end in sequence along the axial direction to form shield tunnel segments;

[0040] Each segment body comprises a plurality of prefabricated component blocks with fan-shaped longitudinal sections;

[0041] A plurality of prefabricated component blocks are connected to each other through the end faces of each two adjacent prefabricated component blocks facing each other to form an annular segment body;

[0042] A double-layer heat exchange pipeline 4 is provided in the steel cage of each prefabricated component block, close to the outer wall and the inner wall of the corresponding shield tunnel respectively;

[0043] In the double-layer heat exchange pipeline 4 of each prefabricated component block, the heat exchange pipeline 4 close to the outer wall of the corresponding shield tunnel is the outer pipeline 401, and the heat exchange pipeline 4 close to the inner wall of the corresponding shield tunnel is the inner pipeline 402;

[0044] At both ends of each prefabricated component block, grooves 10 are provided corresponding to the positions of the inner wall of the corresponding shield tunnel;

[0045] Both ends of each heat exchange pipeline 4 in each prefabricated component block are exposed at the corresponding groove 10 position in a structure perpendicular to the corresponding end surface;

[0046] The multiple inner pipes 402 and the multiple outer pipes 401 in the multiple prefabricated component blocks of each tube segment body are connected end to end in sequence to form an inner and outer two-ring heat exchange unit;

[0047] Each heat exchange unit is connected to the water supply pipe 5 and the return pipe 6 at its head and tail ends, either alone or in series with other adjacent heat exchange units;

[0048] The water supply pipe 5 and the return pipe 6 are connected to the heat pump to form a circulation of the heat-carrying fluid in the shield tunnel segment.

[0049] In practical applications, the segment body is a universal component that can be used in various shield tunnels, and is the same as a conventional tunnel prefabricated segment, and its size, specification, reinforcement, etc. are not affected by the heat exchange pipeline 4.

[0050] The outer pipeline 401 close to the outer wall of the corresponding shield tunnel and the inner pipeline 402 close to the inner wall of the corresponding shield tunnel can ensure the maximum heat exchange efficiency, but must be installed on the inner side of the outer steel bars of the steel cage. In the case where the protective layer is made of fiber concrete or high-strength concrete, after demonstrating the overall mechanical properties of the rear shield segment, the outer pipeline 401 or the inner pipeline 402 can be installed in the protective layer outside the steel cage.

[0051] In order to enable the heat exchange pipelines 4 between different segments to be connected inside the tunnel, a groove 10 is reserved at both ends of the annular direction of the inner side of each prefabricated component block corresponding to the shield tunnel segment;

[0052] like Figure 1 As shown, both ends of each heat exchange pipeline 4 in each prefabricated component block are exposed at the corresponding groove 10 in a structure perpendicular to the corresponding end surface to ensure that the exposed heat exchange pipelines 4 of two adjacent prefabricated component blocks are exactly opposite to each other for easy connection.

[0053] The multiple heat exchange pipes 4 connected end to end of each ring heat exchange unit are connected to the water supply pipe 5 in a certain docked groove 10. In order to reduce the distance from the water supply pipe 5 to the access groove 10, it is advisable to select a groove 10 closest to the water supply pipe 5 as the head and tail ends of the ring heat exchange unit.

[0054] If the heat exchange pipeline 4 in each single-ring tube segment is connected with the water supply pipe 5 and the return pipe 6, the port of the heat exchange pipeline 4 exposed in the adjacent tube segment 1 is directly connected to the return pipe 6 in the reserved groove 10 where the heat exchange pipeline 4 is connected to the water supply pipe 5.

[0055] If the heat exchange pipe 4 in every two or more rings of tube segments is connected with the water supply pipe 5 and the return pipe 6, the port of the heat exchange pipe 4 connected to the reserved groove 10 of the water supply pipe 5 is first connected to the port of a heat exchange pipe 4 in the nearest reserved groove 10 of the adjacent ring, and the port of another heat exchange pipe 4 in the same groove 10 on the adjacent ring is connected to the return pipe 6, thereby forming a loop with two rings of tube segments. The number of tube segments used in the loop can be calculated to ensure the maximum heat exchange efficiency, and usually 2 to 3 rings can be selected as one loop.

[0056] In some embodiments, the plurality of prefabricated component blocks are divided into standard blocks 1, adjacent blocks 2 and capping blocks 3 in descending order according to the size of the central angle of the corresponding segment body;

[0057] When the arc length of any capping block 3 is insufficient for the corresponding heat exchange pipeline 4 to bend back in the corresponding reinforcement cage, a connecting pipe for connecting the heat exchange pipelines 4 in two adjacent prefabricated component blocks is arranged in the reinforcement cage of the capping block 3 with insufficient arc length.

[0058] In some embodiments, each groove 10 is disposed at a midpoint between an edge formed by an end surface of a corresponding prefabricated component block and the concave arc surface.

[0059] In practical applications, the groove 10 should be kept at a certain distance from other reserved holes on the pipe segment. In this embodiment, the groove 10 is arranged in the middle of the pipe segment, which can ensure the symmetry of the two sides of the pipe segment and facilitate installation.

[0060] In some embodiments, the outer pipeline 401 of each prefabricated component block starts from the last bend structure near the two ends and moves toward the inner arc surface of the corresponding shield tunnel, and is exposed from the corresponding groove 10 in a relative position parallel to the corresponding inner pipeline 402.

[0061] In some embodiments, a plurality of prefabricated component blocks connected end to end in each ring heat exchange unit are connected by linear joints 8 disposed in two corresponding joined grooves 10 .

[0062] In some embodiments, the flow directions of the heat transfer fluid in the two-ring heat exchange units corresponding to every two adjacent tube sheet bodies are opposite.

[0063] In practical applications, if two or more rings of tube segments are interconnected, the outer pipeline 401 and the inner pipeline 402 in two adjacent rings of tube segments can be interconnected, and the flow direction of the heat-carrying fluid in the two rings of heat exchange units corresponding to each two adjacent tube segment bodies can flow in the same direction or in opposite directions. However, when the heat-carrying fluid in the two adjacent rings of heat exchange units flows in opposite directions, the heat extraction efficiency can be improved.

[0064] In some embodiments, the water supply pipe 5 and the return pipe 6 are respectively connected to the head end and the tail end of each heat exchange unit, or the head end and the tail end of multiple heat exchange units connected in series, through multiple transition pipes 11;

[0065] Each transition pipe 11 has a tee joint 7 at one end connected to the water supply pipe 5 or the return pipe 6, and a right-angle elbow 9 at one end connected to the head end or tail end of each heat exchange unit, or the head end or tail end of multiple heat exchange units connected in series.

[0066] In some embodiments, each three-way connector 7 is provided with a valve.

[0067] In practical applications, when each heat exchange unit or any heat exchange pipeline 4 in multiple heat exchange units connected in series is under maintenance or when the heat exchange pipeline 4 is stopped from being used, the valve on the three-way joint 7 can be closed to prevent the heat carrier fluid from flowing into the heat exchange pipeline 4.

[0068] In some embodiments, the layout direction of each heat exchange pipeline 4 is parallel to the axial direction or tangential direction of the corresponding shield tunnel segment.

[0069] like Figure 3 The layout direction of the heat exchange pipeline 4 can be parallel to the tunnel direction, that is, the axial direction of the shield tunnel segment. In this way, the number of bends of the heat exchange pipeline 4 is not limited, which is convenient for adjusting the spacing of the pipelines.

[0070] like Figure 4 The layout direction of the heat exchange pipeline 4 can be perpendicular to the tunnel direction, that is, the tangent direction of the shield tunnel segment. When adopting this layout scheme, the number of heat exchange pipelines 4 in the direction must be an odd number, so as to ensure that the heat exchange pipeline 4 is exposed in the groove 10 at the other end of the segment 1.

[0071] In some embodiments, the water supply pipe 5 and the return pipe 6 are both arranged near the bottom of the shield tunnel segment, that is, the lower half of the corresponding tunnel.

[0072] In order to facilitate installation and management, the water supply pipe 5 and the return pipe 6 should be installed in the lower part of the tunnel. Figure 1 The pipe segments 1 are generally installed on one side of the vertical symmetry axis of the tunnel, or on both sides of the symmetry axis. Because the pipe segments 1 are generally overlapped with each other, the water supply pipe 5 and the return pipe 6 are preferably installed in the middle of the adjacent axial joints of two adjacent ring pipe segments.

[0073] When the shield segments are cast, the heat exchange pipeline 4 is arranged in advance in the template and cast together with the prefabricated component blocks to form a whole. The arrangement direction of the heat exchange pipeline 4 can be parallel or perpendicular to the tunnel direction.

[0074] The heat exchange pipeline 4 is made of polyethylene pipe and is tied together with steel bars at corresponding positions.

[0075] The transition pipe 11 uses the same polyethylene pipe or rubber pipe as the heat exchange pipe 4, and adopts certain insulation measures.

[0076] The heat-carrying fluid is generally clean water. In high-altitude and cold areas, antifreeze needs to be added to the heat-carrying fluid.

[0077] In practical applications, the present invention can achieve heating or cooling through the circulation of the heat-carrying fluid in the pipeline. During heating, the low-temperature heat-carrying fluid flows into the heat exchange pipeline 4 through the water supply pipe 5. After passing through the tube sheet 1, the temperature of the fluid rises by absorbing the heat in the tube sheet 1, and then flows into the return pipe 6, and then is connected to the heat pump through the return pipe 6. After cooling at one end of the heat pump evaporator, it flows back to the heat exchange pipeline 6 in the tube sheet through the water supply pipe 5, thereby forming a cycle to achieve the effect of heating. During cooling, the high-temperature heat-carrying fluid flows into the heat exchange pipeline 4 through the water supply pipe 5. After passing through the tube sheet 1, the temperature of the fluid drops by releasing the heat in the fluid into the tube sheet 1, and then flows into the return pipe 6, and then is connected to the heat pump through the return pipe 6. After heating at one end of the heat pump condenser, it flows back to the heat exchange pipeline 6 in the tube sheet through the water supply pipe 5, thereby forming a cycle to achieve the effect of cooling.

[0078] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A prefabricated segment for a double-layered shield tunnel capable of collecting geothermal energy, comprising a general annular segment body; The plurality of segment bodies are sequentially spliced ​​end to end along the axial direction to form a shield tunnel segment; Each of the segment bodies comprises a plurality of prefabricated component blocks with fan-shaped longitudinal sections; A plurality of the prefabricated component blocks are connected to each other through the end faces of each two adjacent prefabricated component blocks facing each other to form the annular segment body; characterized in that: A double-layer heat exchange pipeline (4) is provided in the steel cage of each prefabricated component block and is close to the outer wall and the inner wall of the corresponding shield tunnel respectively; In the double-layer heat exchange pipeline (4) of each prefabricated component block, the heat exchange pipeline (4) close to the outer wall of the corresponding shield tunnel is the outer pipeline (401), and the heat exchange pipeline (4) close to the inner wall of the corresponding shield tunnel is the inner pipeline (402); Both ends of each of the prefabricated component blocks are provided with grooves (10) corresponding to positions on the inner wall of the corresponding shield tunnel; Both ends of each heat exchange pipeline (4) in each prefabricated component block are exposed at the corresponding groove (10) in a structure perpendicular to the corresponding end surface; The plurality of inner pipelines (402) in the plurality of prefabricated component blocks of each of the tube segment bodies and the plurality of outer pipelines (401) are respectively connected end to end in sequence to form an inner and outer two-ring heat exchange unit; Each heat exchange unit is connected alone or in series with other adjacent heat exchange units, and the head end and tail end are respectively connected to the water supply pipe (5) and the return pipe (6); The water supply pipe (5) and the return pipe (6) are connected to a heat pump to form a circulation of the heat-carrying fluid in the shield tunnel segment; The flow directions of the heat transfer fluid in the heat exchange unit of the two rings corresponding to each two adjacent tube sheet bodies are opposite; The outer pipeline (401) of each prefabricated component block starts from the last bend structure near the two ends and moves toward the corresponding inner arc surface of the shield tunnel, and is exposed from the corresponding groove (10) in a relative position parallel to the corresponding inner pipeline (402).

2. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 1 is characterized in that: The plurality of prefabricated component blocks are divided into standard blocks (1), adjacent blocks (2) and capping blocks (3) in descending order according to the size of the central angle of the main body of the pipe segment; When the arc length of any capping block (3) is insufficient for the corresponding heat exchange pipeline (4) to bend back in the corresponding steel cage, a connecting pipe for connecting the heat exchange pipelines (4) in two adjacent prefabricated component blocks is provided in the steel cage of the capping block (3) with insufficient arc length.

3. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 1 is characterized in that: Each of the grooves (10) is arranged at a middle position of an edge formed by the end surface and the concave arc surface of the corresponding prefabricated component block.

4. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 1 is characterized in that: The plurality of prefabricated component blocks connected end to end in each ring of the heat exchange unit are connected via linear joints (8) arranged in the corresponding two assembled grooves (10).

5. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 1 is characterized in that: The water supply pipe (5) and the return pipe (6) are both arranged at a position close to the bottom of the shield tunnel segment, that is, the lower half of the corresponding tunnel.

6. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 1 is characterized in that: The water supply pipe (5) and the return pipe (6) are respectively connected to the head end and tail end of each heat exchange unit, or the head end and tail end of a plurality of heat exchange units connected in series, through a plurality of transition pipes (11); Each of the transition pipes (11) is provided with a three-way joint (7) at one end connected to the water supply pipe (5) or the return pipe (6), and a right-angle elbow (9) is provided at one end connected to the head end or tail end of each heat exchange unit, or the head end or tail end of a plurality of heat exchange units connected in series.

7. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 6 is characterized in that: Each of the three-way connectors (7) is provided with a valve.

8. The double-layer pipeline shield tunnel prefabricated segment capable of collecting geothermal energy according to claim 1 is characterized in that: The layout direction of each of the heat exchange pipelines (4) is parallel to the axial direction or tangential direction of the corresponding shield tunnel segment.

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