A geothermal heat exchange system

Abstract

The present invention discloses a geothermal energy heat exchange system, including a hot and cold energy utilization unit, and also includes: a heat exchange pipe, which is arranged within the lining range on both sides of the middle box culvert of the equipment layer in the lower layer of the shield tunnel. The inlet end of the heat exchange pipe is connected to the water supply main pipe, and the outlet end is connected to the return water main pipe. By fully utilizing the characteristics of the separation of the shield tunnel driving lane layer and the equipment layer, a heat exchange pipe is pre-buried in the shield tunnel equipment layer, and circulates heat exchange with the heat pump system to provide cooling or heating to the user side, effectively replacing the traditional underground pipe ground source heat pump system of the buildings around the tunnel, which can save underground space and is conducive to the development and utilization of underground space.

Description

Technical Field

[0001] The present invention relates to the field of energy tunnels, and in particular to a geothermal energy heat exchange system. Background Art

[0002] A geothermal heat pump is a highly efficient, energy-saving, and environmentally friendly air conditioning system that utilizes shallow geothermal resources for both heating and cooling. Ground-source heat pumps typically utilize buried pipes for outdoor geothermal heat exchange. These pipes are buried shallowly in the soil, with circulating water exchanging heat directly with the soil through the pipe walls. Ground temperatures below 10 to 15 meters are essentially constant, and geothermal heat pumps typically utilize this soil heat for geothermal heat exchange.

[0003] Although the layout of soil buried pipes is flexible, a large number of buried holes need to be drilled in places with high energy demand, which will occupy a large amount of underground space and is not conducive to the development and utilization of underground space. Summary of the Invention

[0004] The present invention aims to provide a geothermal heat exchange system for use in shield tunnels, which can solve the problem in the prior art that soil buried pipes occupy a large amount of underground space.

[0005] According to one aspect of the present invention, a geothermal energy heat exchange system for a shield tunnel is provided, comprising a heat and cold energy utilization unit, and further comprising: a heat exchange pipe arranged within the lining range on both sides of the middle box culvert in the equipment layer of the lower layer of the shield tunnel, the inlet end of the heat exchange pipe being connected to the water supply main pipe, and the outlet end being connected to the return water main pipe.

[0006] Preferably, the equipment layer is only connected to the shield shaft.

[0007] Preferably, the heat exchange tubes are arranged in a U-shaped fold along the longitudinal direction of the tunnel, the longitudinal arrangement length is determined according to the length of the cast-in-place section of the shield tunnel lining, and the circumferential arrangement spacing is adjusted according to the setting range of the shield tunnel lining.

[0008] Preferably, the heat exchange tube is fixed to the inner lining steel bar with a cable tie to ensure the stability of the heat exchange tube during the concrete pouring process; the straight sections of the heat exchange tube are tied at equal intervals, and the tying interval is not greater than 500mm, and the turning sections of the heat exchange tube are tied more densely.

[0009] Preferably, a maintenance valve or a manifold is provided at the connection portion between the heat exchange tube and the water supply main pipe and the return water main pipe. The manifold is used to balance and adjust the flow of the heat exchange tube according to the load demand of the heat and cold energy utilization unit.

[0010] Preferably, the water supply main pipe consists of a horizontal section water supply main pipe and a vertical section water supply main pipe; the return water main pipe consists of a horizontal section return water main pipe and a vertical section return water main pipe; the water supply main pipe and the return water main pipe are provided with insulation facilities; the horizontal section water supply main pipe and the horizontal section return water main pipe are arranged in the equipment layer, and the vertical section water supply main pipe and the vertical section return water main pipe are arranged in the shield shaft.

[0011] Preferably, the heat exchange pipe, the water supply main pipe and the return water main pipe adopt the same-type heat exchange pipeline; the water supply main pipe and the return water main pipe are provided with a corrugated compensator at a certain distance, the high points of the water supply main pipe and the return water main pipe are provided with automatic exhaust valves, and the low points are provided with drain valves.

[0012] Preferably, the geothermal heat exchange system of the shield tunnel further comprises: a heat pump unit, which is a water-water ground source heat pump unit or a water-air ground source heat pump unit.

[0013] Preferably, the heat pump unit adjusts its operating parameters and the number of heat exchange pipelines in use according to the load demand of the heat and cold energy utilization unit.

[0014] Preferably, the geothermal heat exchange system of the shield tunnel further comprises: a power module for providing power for the heat exchange pipeline and the hydraulic circulation of the heat and cold energy utilization unit.

[0015] The present invention discloses a geothermal heat exchange system, comprising a heat and cold energy utilization unit and heat exchange pipes arranged within the inner lining of a box culvert located in the lower equipment layer of a shield tunnel. The heat exchange pipes have inlets connected to a water supply main and outlets connected to a return water main. By fully utilizing the separation between the roadway layer and the equipment layer of a shield tunnel, the present invention pre-buries heat exchange pipes in the equipment layer of the shield tunnel, circulates heat with a heat pump system, and provides cooling or heating to users. This effectively replaces the traditional buried ground-source heat pump systems in buildings surrounding the tunnel, conserving underground space and facilitating its development and utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 is a schematic diagram of a geothermal heat exchange system according to an embodiment of the present invention;

[0018] Figure 2 A schematic cross-sectional view of a shield tunnel pipeline arrangement according to an embodiment of the present invention;

[0019] Figure 3 Schematic diagram of longitudinal and circumferential arrangement of heat exchange tubes according to an embodiment of the present invention;

[0020] Figure 4 Schematic diagram of tying a heat exchange tube with a tie according to an embodiment of the present invention;

[0021] In the figure: 1. Shield shaft; 2. Heat pump unit; 3. Power module; 4. Heat and cold energy utilization unit; 5. Heat exchange pipeline; 6. Water supply main pipe; 61. Horizontal section water supply main pipe; 62. Vertical section water supply main pipe; 7. Return water main pipe; 71. Horizontal section return water main pipe; 72. Vertical section return water main pipe; 8. Control valve; 9. Bellows compensator; 10. Inspection valve; 11. Cable tie; 12. Rebar. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. For ease of interpretation and precise definition in the appended claims, the terms "upper," "lower," "inner," and "outer" are used to describe features of the exemplary embodiments with reference to their positions as shown in the drawings.

[0024] Figures 1-4 The figure shows a schematic diagram of a geothermal heat exchange system according to an embodiment of the present invention, a cross-sectional schematic diagram of the shield tunnel piping layout, longitudinal and circumferential layout diagrams of the heat exchange tubes, and a schematic diagram of the heat exchange tube tie binding. As shown, the present invention provides a geothermal heat exchange system comprising a heat and cold energy utilization unit 4 and heat exchange tubes 5 arranged within the inner lining of the box culvert on both sides of the equipment layer in the lower level of the shield tunnel. The inlet of the heat exchange tubes 5 is connected to a water supply main 6, and the outlet is connected to a return water main 7.

[0025] In the related art, soil buried pipes are usually used as outdoor geothermal heat exchange systems. For places with large energy demands, a large number of buried holes need to be drilled, which occupies a large amount of underground space and is not conducive to the development and utilization of underground space. The embodiment of the present invention makes full use of the construction space of the shield tunnel, replaces the traditional buried pipe ground source heat pump system of the buildings around the tunnel, provides a cold and heat source for the surrounding buildings, and helps achieve carbon neutrality. Among them, the heat exchange pipe 5 is connected to the water supply main pipe 6 and the return water main pipe 7 to form a closed-loop heat exchange system. The system effectively utilizes the ground temperature energy for cold and heat exchange by arranging the heat exchange pipe 5 in the equipment layer of the shield tunnel, which can save underground space and ensure the stability and service life of the system.

[0026] According to an embodiment of the present invention, the equipment layer is only connected to the shield shaft 1.

[0027] In related technologies, buried pipes are buried in shallow soil, with circulating water exchanging heat directly with the soil through the pipe walls. In this embodiment, the equipment layer is connected only to the shield shaft. Therefore, when ventilation is not performed on the equipment layer, the internal environment is far less affected by the external environment than the roadway layer, resulting in higher heat exchange efficiency than the roadway layer.

[0028] According to an embodiment of the present invention, the heat exchange tube 5 is arranged in a U-shaped return along the longitudinal direction of the tunnel. The longitudinal arrangement length is determined according to the length of the cast-in-place section of the shield tunnel lining, and the circumferential arrangement spacing is adjusted according to the setting range of the shield tunnel lining.

[0029] According to an embodiment of the present invention, the heat exchange tube 5 is fixed to the inner lining steel bar 12 by using a cable tie 11 to ensure the stability of the heat exchange tube 5 during the concrete pouring process; the straight pipe sections of the heat exchange tube 5 are tied at equal intervals, and the tying interval is not greater than 500 mm, and the turning sections of the heat exchange tube 5 are tied more densely.

[0030] Conventional soil-buried pipe methods require detailed analysis of parameters such as hydrogeological conditions, and installation is technically challenging. In this embodiment, the heat exchange tubes 5 are secured to the inner lining steel bars 12 using cable ties 11, significantly reducing installation complexity. After concrete pouring, the heat exchange tubes are minimally displaced, ensuring controlled installation quality.

[0031] According to an embodiment of the present invention, a maintenance valve 10 or a manifold is provided at the connection portion between the heat exchange tube 5 and the water supply main pipe 6 and the return water main pipe 7. The manifold is used to balance and adjust the flow of the heat exchange tube 5 according to the load demand of the heat and cold energy utilization unit 4.

[0032] In the embodiment of the present invention, the use of the manifold improves the regulation capability and flow balance of the system. The regulation according to the user-side load demand makes the system more energy-efficient and efficient, and meets the personalized needs of different users.

[0033] According to an embodiment of the present invention, the water supply main pipe 6 is composed of a horizontal section water supply main pipe 61 and a vertical section water supply main pipe 62; the return water main pipe 7 is composed of a horizontal section return water main pipe 71 and a vertical section return water main pipe 72; the water supply main pipe 6 and the return water main pipe 7 are provided with insulation facilities; the horizontal section water supply main pipe 61 and the horizontal section return water main pipe 71 are arranged in the equipment layer, and the vertical section water supply main pipe 62 and the vertical section return water main pipe 72 are arranged in the shield shaft 1.

[0034] According to an embodiment of the present invention, the heat exchange pipe 5, the water supply main pipe 6 and the return water main pipe 7 adopt the same-type heat exchange pipeline; the water supply main pipe 6 and the return water main pipe 7 are provided with a corrugated compensator 9 at a certain distance, and automatic exhaust valves are provided at the high points of the water supply main pipe 6 and the return water main pipe 7, and a drain valve is provided at the low points.

[0035] In the embodiment of the present invention, the design of the same-flow heat exchange pipeline ensures the uniform distribution and collection of the fluid, the setting of the corrugated compensator 9 improves the safety and maintainability of the system, and the setting of the automatic exhaust valve and drain valve contributes to the stable operation and maintenance of the system.

[0036] According to an embodiment of the present invention, the geothermal heat exchange system of the shield tunnel further includes: a heat pump unit 2, which is a water-water ground source heat pump unit or a water-air ground source heat pump unit.

[0037] In the embodiment of the present invention, the flexible design of the heat pump unit 2 enables the system to be optimally configured according to actual needs.

[0038] According to an embodiment of the present invention, the heat pump unit 2 adjusts its operating parameters and the number of heat exchange pipes 5 in use according to the load demand of the heat and cold energy utilization unit 4 .

[0039] During the implementation of the embodiment of the present invention, the load of the heat pump unit 2 can be determined according to the load demand of the user side 4 and the number of heat exchange pipelines 5 used can be adjusted, so that the shield tunnel heat exchange pipelines 5 match the user side usage demand.

[0040] According to an embodiment of the present invention, the geothermal heat exchange system of the shield tunnel further includes: a power module 3 for providing power for the hydraulic circulation of the heat exchange pipeline 5 and the heat and cold energy utilization unit 4.

[0041] According to an embodiment of the present invention, CFD simulation technology is used to simulate the fluid flow and heat transfer inside the heat exchange tube 5 to predict the fluid dynamics behavior and heat transfer efficiency under the circumferential arrangement spacing and the longitudinal arrangement length, and obtain CFD simulation results; dynamic simulation technology is used to analyze the thermal response and fluid flow of the heat exchange tube 5 under different working conditions to determine the circumferential arrangement spacing and the longitudinal arrangement length within the second lining length and setting range of the shield tunnel, and obtain dynamic simulation results; based on the CFD simulation results and the dynamic simulation results, the circumferential arrangement spacing and the longitudinal arrangement length are adjusted.

[0042] The present invention has the following advantages:

[0043] (1) By pre-buried heat exchange pipes in the shield tunnel lining, the original ground source heat pump soil buried pipes are replaced, effectively saving underground space; and less interference from the external environment can effectively ensure durability and service life; at the same time, the environment in the equipment layer is not in direct contact with the atmosphere, and mainly exchanges heat with the soil outside the tunnel and the air in the shield tunnel equipment layer, with stable temperature and high heat exchange efficiency.

[0044] (2) The tunnel lining is constructed using a cast-in-place process. The heat exchange pipes can be tied and fixed to the lining steel bars. After the concrete is poured, the displacement of the heat exchange pipes is small and the installation quality is controllable.

[0045] (3) By utilizing the principle of ground source heat pump, the temperature change of the heat exchange pipeline is small and has no impact on the safety of the existing structure.

[0046] (4) The water supply and return main pipelines are arranged in the shield tunnel equipment layer, and the pipeline accessories can be installed openly on the equipment layer, making the system easy to maintain.

[0047] The above embodiments are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications may be made based on the following description. These variations, modifications, substitutions, and variations arising from the principles and spirit of the present invention are still within the scope of protection of the present invention.

Claims

1. A geothermal heat exchange system, comprising a heat and cold energy utilization unit (4), characterized in that: Also includes: Heat exchange pipes (5) are arranged within the inner lining range on both sides of the middle box culvert in the equipment layer of the lower layer of the shield tunnel, the inlet end of the heat exchange pipe (5) is connected to the water supply main pipe (6), and the outlet end is connected to the return water main pipe (7), wherein the equipment layer is only connected to the shield shaft (1); The heat exchange tubes (5) are arranged in a U-shaped return pattern along the longitudinal direction of the tunnel, the longitudinal arrangement length is determined according to the length of the cast-in-situ section of the shield tunnel lining, and the circumferential arrangement spacing is adjusted according to the setting range of the shield tunnel lining; The heat exchange tube (5) is fixed to the inner lining steel bar (12) using a tie (11) to ensure the stability of the heat exchange tube (5) during the concrete pouring process; The straight sections of the heat exchange tube (5) are tied at equal intervals, and the spacing between the ties is no greater than 500 mm, and the turning sections of the heat exchange tube (5) are tied more densely; A maintenance valve (10) or a manifold is provided at the connection portion between the heat exchange tube (5) and the water supply main pipe (6) and the return water main pipe (7), and the manifold is used to balance and adjust the flow of the heat exchange tube (5) according to the load demand of the heat and cold energy utilization unit (4); The water supply main pipe (6) is composed of a horizontal section water supply main pipe (61) and a vertical section water supply main pipe (62); The return water main pipe (7) is composed of a horizontal section return water main pipe (71) and a vertical section return water main pipe (72); The water supply main pipe (6) and the water return main pipe (7) are provided with heat insulation facilities; The horizontal section water supply main pipe (61) and the horizontal section water return main pipe (71) are arranged in the equipment layer, and the vertical section water supply main pipe (62) and the vertical section water return main pipe (72) are arranged in the shield shaft (1); The heat exchange pipe (5), the water supply main pipe (6) and the return water main pipe (7) adopt the same heat exchange pipeline; A corrugated compensator (9) is provided at a certain distance between the water supply main pipe (6) and the return water main pipe (7), and an automatic exhaust valve is provided at the high point of the water supply main pipe (6) and the return water main pipe (7), and a drain valve is provided at the low point.

2. The heat exchange system according to claim 1, characterized in that: Also includes: A heat pump unit (2), wherein the heat pump unit (2) is a water-water ground source heat pump unit or a water-air ground source heat pump unit.

3. The heat exchange system according to claim 2, characterized in that The heat pump unit (2) adjusts its operating parameters and the number of heat exchange tubes (5) used according to the load demand of the heat and cold energy utilization unit (4).

4. The heat exchange system according to claim 1, characterized in that Also includes: The power module (3) is used to provide power for the hydraulic circulation of the heat exchange tube (5) and the heat and cold energy utilization unit (4).

Images