Ground temperature energy heat exchange system

Abstract

The invention discloses a ground temperature energy heat exchange system which comprises a hot and cold energy utilization unit and further comprises a heat exchange pipe arranged in the range of linings on the two sides of a middle box culvert of an equipment layer on the lower layer of a shield tunnel, the inlet end of the heat exchange pipe is connected with a water supply main pipe, and the outlet end of the heat exchange pipe is connected with a water return main pipe. By fully utilizing the characteristic that a shield tunnel carriageway layer is separated from an equipment layer, a heat exchange pipeline is pre-buried in the equipment layer of the shield tunnel, circularly exchanges heat with a heat pump system and supplies cold or heat to a user side, so that a traditional buried pipe ground source heat pump system of a building around the tunnel is effectively replaced, underground space can be saved, and development and utilization of the underground space are facilitated.

Description

Technical Field

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

[0002] A geothermal heat pump is an efficient, energy-saving and environmentally friendly air conditioning system that uses shallow underground geothermal resources for both heating and cooling. Soil buried pipes are usually used as outdoor geothermal heat exchange systems. The soil buried pipes are buried in the shallow underground soil, and the circulating water directly exchanges heat with the soil through the water pipe wall. The ground temperature is basically constant below a burial depth of 10 to 15 meters, and a geothermal heat pump usually uses this part of the soil heat energy 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 heat exchange system for a shield tunnel is provided, comprising a heat and cold energy utilization unit, and also comprising: a heat exchange pipe 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.

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

[0007] Preferably, the heat exchange tubes 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 primary 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 concrete pouring; the straight tube sections of the heat exchange tube are tied at equal intervals, and the tying interval is no more 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, and 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 consists of a horizontal section water supply main and a vertical section water supply main; the return water main consists of a horizontal section return water main and a vertical section return water main; the water supply main and the return water main are provided with insulation facilities; the horizontal section water supply main and the horizontal section return water main are arranged in the equipment layer, and the vertical section water supply main and the vertical section return water main 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-to-water ground source heat pump unit or a water-to-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, including a heat and cold energy utilization unit, and also including: a heat exchange pipe, arranged in 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. The present invention fully utilizes the characteristics of the separation of the driving lane layer and the equipment layer of the shield tunnel, pre-buries the heat exchange pipeline in the equipment layer of the shield tunnel, performs cyclic heat exchange with the heat pump system, and provides cooling or heating to the user side, effectively replacing the traditional buried pipe ground source heat pump system of the surrounding buildings of the tunnel, which can save underground space and is conducive to the development and utilization of underground space. 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 The longitudinal and circumferential arrangement diagram of the 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; 61. Horizontal section water supply main; 62. Vertical section water supply main; 7. Return main; 71. Horizontal section return main; 72. Vertical section return main 8. Regulating 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 in the embodiments of the present 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 shown 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 shown in the drawings with reference to their positions.

[0024] Figure 1-Figure 4 The schematic diagram of the geothermal heat exchange system according to an embodiment of the present invention, the cross-sectional schematic diagram of the shield tunnel pipeline layout, the longitudinal and circumferential layout diagrams of the heat exchange tubes, and the schematic diagram of the heat exchange tube tie binding are shown. As shown in the figure, the embodiment of the present invention provides a geothermal heat exchange system, including a heat and cold energy utilization unit 4, and also includes: a heat exchange tube 5, 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, and the inlet end of the heat exchange tube 5 is connected to the water supply main pipe 6, and the outlet end is connected to the return water main pipe 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, which 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 to 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 arranges the heat exchange pipe 5 in the equipment layer of the shield tunnel, effectively utilizes the ground temperature energy for cold and heat exchange, can save underground space, and ensure the stability and service life of the system.

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

[0027] In the related art, the soil buried pipe is buried in the shallow soil layer underground, and the circulating water directly exchanges heat with the soil through the water pipe wall. In the embodiment of the present invention, the equipment layer is only connected to the shield shaft. Therefore, when the equipment layer is not ventilated, the environment in the space is far less affected by the external environment than the carriageway layer, and the heat exchange efficiency is higher than that of the carriageway layer, thereby improving the heat exchange efficiency.

[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 first 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 a cable tie 11 to ensure the stability of the heat exchange tube 5 during the concrete pouring process; the straight tube 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 the installation technology is difficult. In the embodiment of the present invention, the heat exchange tube 5 is tied and fixed to the lining steel bar 12 with a tie 11, which greatly reduces the installation technology difficulty. After the concrete is poured, the displacement of the heat exchange pipeline is small, and the installation quality is controllable.

[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, and the regulation according to the load demand on the user side makes the system more energy-efficient and efficient, meeting the personalized needs of different users.

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

[0034] According to an embodiment of the present invention, the heat exchange tube 5, the water supply main pipe 6 and the return main pipe 7 adopt the same-type heat exchange pipeline; the water supply main pipe 6 and the return 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 main pipe 7, and drain valves are provided at the low points.

[0035] In the embodiment of the present invention, the design of the isotropic heat exchange pipeline ensures uniform distribution and collection of the fluid, the provision of the bellows compensator 9 improves the safety and maintainability of the system, and the provision 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-to-water ground source heat pump unit or a water-to-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 the embodiment of the present invention, the heat pump unit 2 adjusts its operating parameters and the number of heat exchange pipelines 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 annular 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 annular arrangement spacing and the longitudinal arrangement length within the second lining length and setting range of the shield tunnel, and obtain dynamic simulation results; according to the CFD simulation results and the dynamic simulation results, the annular arrangement spacing and the longitudinal arrangement length are adjusted.

[0042] The present invention has the following advantages:

[0043] (1) By pre-burying heat exchange pipelines in the lining of the shield tunnel, the original soil buried pipes of the ground source heat pump are replaced, which effectively saves underground space; and is less affected by the external environment, which can effectively ensure durability and service life; at the same time, the environment inside the equipment layer is not in direct contact with the atmosphere, and mainly exchanges heat with the soil outside the tunnel and the air inside 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 pipeline can be tied and fixed to the lining steel bars. After the concrete is poured, the displacement of the heat exchange pipeline is small and the installation quality is controllable.

[0045] (3) 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 equipment layer of the shield tunnel, and the pipeline accessories can be exposedly installed in the equipment layer, making the system easy to maintain.

[0047] The above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications may be made based on the following description, and these various changes, modifications, substitutions and deformations derived from the principles and spirit of the present invention still fall 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: The heat exchange pipe (5) 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 (5) is connected to the water supply main pipe (6), and the outlet end is connected to the return water main pipe (7).

2. The heat exchange system according to claim 1, characterized in that: The equipment layer is only connected to the shield shaft (1).

3. The heat exchange system according to claim 2, characterized in that: 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 primary 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.

4. The heat exchange system according to claim 3, characterized in that: The heat exchange tube (5) is fixed to the inner lining steel bar (12) by means of 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 tying is no greater than 500 mm, and the turning sections of the heat exchange tube (5) are tied more densely.

5. The heat exchange system according to claim 4, characterized in that: A check 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 water return 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).

6. The heat exchange system according to claim 5, characterized in that: 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 water return main pipe (7) is composed of a horizontal section water return main pipe (71) and a vertical section water return main pipe (72); The water supply main pipe (6) and the water return main pipe (7) are provided with heat preservation 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).

7. The heat exchange system according to claim 6, characterized in that: The heat exchange pipe (5), the water supply main pipe (6) and the water return main pipe (7) adopt the same heat exchange pipeline; A corrugated compensator (9) is arranged at a certain distance between the water supply main pipe (6) and the water return main pipe (7), and an automatic exhaust valve is arranged at the high point of the water supply main pipe (6) and the water return main pipe (7), and a drain valve is arranged at the low point.

8. 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-to-water ground source heat pump unit or a water-to-air ground source heat pump unit.

9. The heat exchange system according to claim 8, characterized in that: The heat pump unit (2) adjusts its operating parameters and the number of heat exchange pipelines (5) in use according to the load demand of the heat and cold energy utilization unit (4).

10. 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 cycle of the heat exchange pipeline (5) and the heat and cold energy utilization unit (4).

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