阅读说明：本技术 一种双源地铁源热泵系统、施工方法及控制方法 (Double-source subway source heat pump system, construction method and control method ) 是由 季永明 吴汶泽 胡松涛 刘国丹 佟振 童力 于 2021-08-03 设计创作，主要内容包括：本发明公开了一种双源地铁源热泵系统、施工方法及控制方法；双源地铁源热泵系统包括空气侧换热器、土壤侧换热器、分水器、集水器、蓄热水箱和热泵系统；蓄热水箱与热泵系统并联；蓄热水箱与热泵系统的出口通过管路与泵相连,泵与分水器相连,分水器与供水总干管相连,供水总干管通过第一三通阀分别与空气侧换热器、土壤侧换热器的供水干管相连；空气侧换热器、土壤侧换热器的回水干管分别通过第二三通阀与回水总干管相连；回水总干管与集水器的入口相连,集水器的出口与蓄热水箱与热泵系统的入口相连。(The invention discloses a double-source subway source heat pump system, a construction method and a control method; the double-source subway source heat pump system comprises an air side heat exchanger, a soil side heat exchanger, a water separator, a water collector, a heat storage water tank and a heat pump system; the heat storage water tank is connected with the heat pump system in parallel; the heat storage water tank and the outlet of the heat pump system are connected with a pump through a pipeline, the pump is connected with a water separator, the water separator is connected with a water supply main pipe, and the water supply main pipe is respectively connected with water supply main pipes of an air side heat exchanger and a soil side heat exchanger through a first three-way valve; the water return main pipes of the air side heat exchanger and the soil side heat exchanger are respectively connected with a water return main pipe through a second three-way valve; the backwater main pipe is connected with an inlet of a water collector, and an outlet of the water collector is connected with a heat storage water tank and an inlet of a heat pump system.)

1. A dual-source subway source heat pump system is characterized by comprising an air side heat exchanger, a soil side heat exchanger, a water separator, a water collector, a heat storage water tank and a heat pump system;

the heat storage water tank is connected with the heat pump system in parallel; the heat storage water tank and the outlet of the heat pump system are connected with a pump through a pipeline, the pump is connected with a water separator, the water separator is connected with a water supply main pipe, and the water supply main pipe is respectively connected with water supply main pipes of an air side heat exchanger and a soil side heat exchanger through a first three-way valve; the water return main pipes of the air side heat exchanger and the soil side heat exchanger are respectively connected with a water return main pipe through a second three-way valve; the backwater main pipe is connected with an inlet of a water collector, and an outlet of the water collector is connected with a heat storage water tank and an inlet of a heat pump system.

2. A dual-source heat pump system as claimed in claim 1, wherein the soil-side heat exchanger comprises a soil-side water supply main and a first water return main; the air side heat exchanger comprises an air side water supply main pipe and a second water return main pipe; the air side water supply main pipe is communicated with the soil side water supply main pipe, and a fifth bypass valve is arranged on the communicating pipeline; the second water return main pipe is communicated with the second water return main pipe, and a sixth bypass valve is arranged on the communicating pipeline; a first bypass valve is connected between the inlet side of the soil side water supply main pipe and the first water return main pipe; a third bypass valve is connected between the tail end of the soil side water supply main pipe and the first water return main pipe; a second bypass valve is connected between the inlet side of the air side water supply main pipe and the second water return main pipe; and a fourth bypass valve is connected between the tail end of the air side water supply main pipe and the second water return main pipe.

3. The dual-source underground source heat pump system according to claim 2, wherein the soil side water supply main pipe and the air side water supply main pipe are in a double-spiral structure along an underground continuous wall on the inner side of the air shaft from the upper part of the tunnel.

4. The dual-source subway source heat pump system as claimed in claim 2, wherein said first and second water return main pipes are in double helix structure along underground continuous wall inside air shaft from the upper part of tunnel.

5. The dual-source subway source heat pump system as claimed in claim 2, wherein the soil side water supply main, the first water return main, the air side water supply main and the second water return main are all fixed in the reinforcement cage.

6. A dual-source heat pump system as claimed in claim 2, wherein a branch pipe is connected between the soil-side water supply main pipe and the first water return main pipe, and the branch pipe is fixed by a pipe hoop.

7. The dual-source subway source heat pump system as claimed in claim 1, wherein a temperature sensor and a flow sensor are installed on the water supply main pipe; a temperature sensor and a flow sensor are also arranged on the backwater main pipe.

8. A dual source underground source heat pump system as claimed in claim 1 wherein the air side heat exchanger and the soil side heat exchanger are mounted in a piston shaft.

9. The control method of the dual-source subway source heat pump system as claimed in any one of claims 2-6,

when the working condition is the parallel working condition of the air side and the soil side, the water supply main pipe of the air side heat exchanger and the water supply main pipe of the soil side heat exchanger are both opened, the first water return main pipe and the second water return main pipe are opened, the first bypass valve, the second bypass valve, the fifth bypass valve and the sixth bypass valve are closed, and the third bypass valve and the fourth bypass valve are opened;

when the working condition is the air side independent working condition; opening a water supply main pipe of the air side heat exchanger, closing a water supply main pipe of the soil side heat exchanger, closing a first water return main pipe, opening a second water return main pipe, opening a fourth bypass valve, and closing other bypass valves;

when the working condition is a soil side independent working condition; opening a water supply main pipe of the soil side heat exchanger, closing a water supply main pipe of the air side heat exchanger, opening a first water return main pipe, closing a second water return main pipe, opening a third bypass valve, and closing other bypass valves;

when the working condition is a series working condition of firstly connecting the soil side and then connecting the air side, the water supply main pipe of the soil side heat exchanger is opened, the water supply main pipe of the air side heat exchanger is closed, the first water return main pipe is opened, the second water return main pipe is closed, the second bypass valve and the fifth bypass valve are opened, and other bypass valves are closed;

when the working condition is a series working condition of firstly connecting the air side and then connecting the soil side, the water supply main pipe of the air side heat exchanger is opened, the water supply main pipe of the soil side heat exchanger is closed, the second water return main pipe is opened, the first water return main pipe is closed, the first bypass valve and the fifth bypass valve are opened, and other bypass valves are closed;

when the water supply main pipe of the air side heat exchanger is opened, the water supply main pipe of the soil side heat exchanger is closed, the first water return main pipe and the second water return main pipe are opened, the first bypass valve, the fourth bypass valve and the fifth bypass valve are opened, and other bypass valves are closed, the flow ratio of the return water of the air side to the soil side can be adjusted by adjusting the opening degree of the valves;

when the water supply main pipe of the air side heat exchanger is closed, the water supply main pipe of the soil side heat exchanger is opened, the first water return main pipe and the second water return main pipe are both opened, the second bypass valve, the third bypass valve and the fifth bypass valve are opened, and when other bypass valves are closed, the flow rate of the return water of the soil side to the air side can be adjusted by adjusting the opening degree of the valves.

10. The construction method of the double-source underground source heat pump system according to any one of claims 2 to 8 is characterized by comprising the following steps:

firstly, completing the construction of an outer underground diaphragm wall and a bottom plate;

after the construction of the bottom plate is finished, weaving a circle of reinforcement cage of the first layer of the inner side underground continuous wall on the bottom plate close to the outer side underground continuous wall, fixing the heat exchange tubes of the heat exchanger, and fixing the heat exchange tubes meeting the requirements on the reinforcement cage;

a water supply main pipe of the air side heat exchanger and a first water return pipe are arranged on the left and right sides and are connected by a branch pipe in the middle; a water supply main pipe of the soil side heat exchanger is positioned under the second water return pipe and is sequentially fixed by the water supply main pipe, the soil side heat exchanger branch pipe and the second water return pipe of the soil side heat exchanger;

after the work is finished, pouring concrete; during pouring, the soil side heat exchanger and the main pipe and the water return pipe of the air side heat exchanger are connected according to requirements;

according to the process, the concrete layer is poured, the steel bars and the fixed heat exchange tubes are firstly woven, then the concrete is poured, and the supports are detached after the concrete meets the requirements until the top.

Technical Field

The invention relates to the field of energy utilization, in particular to a double-source subway source heat pump system, a construction method and a control method.

Background

The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.

The subway can produce a large amount of heat in the operation process, only a small part of the heat is stored in surrounding rocks, and most of the heat is exhausted to the ground through air by piston wind and a tunnel exhaust fan, so that not only is the waste of low-grade heat energy caused, but also high-grade electric energy is wasted. In recent years, in some projects, heat exchange tubes are laid in a diaphragm wall or a tunnel lining of an underground space to serve as a front-end heat exchanger of a ground source heat pump, so that low-grade heat energy stored in subway surrounding rock can be converted into high-grade heat energy to be utilized, a certain positive effect is achieved on the treatment of the heat environment and soil heat pollution of a subway tunnel, and the low-grade heat energy in most of subway tunnels cannot be utilized. And the ventilation efficiency of the existing piston air shaft is low, and along with the increase of the construction depth of the subway, the efficiency is even close to 0, so that more electric energy consumed by a fan is required for radiating the subway tunnel.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a double-source subway source heat pump system, a construction method and a control method.

In order to achieve the purpose, the invention is realized by the following technical scheme:

in a first aspect, an embodiment of the invention provides a dual-source subway source heat pump system, which comprises an air-side heat exchanger, a soil-side heat exchanger, a water separator, a water collector, a heat storage water tank and a heat pump system;

the heat storage water tank is connected with the heat pump system in parallel; the heat storage water tank and the outlet of the heat pump system are connected with a pump through a pipeline, the pump is connected with a water separator, the water separator is connected with a water supply main pipe, and the water supply main pipe is respectively connected with water supply main pipes of an air side heat exchanger and a soil side heat exchanger through a first three-way valve; the water return main pipes of the air side heat exchanger and the soil side heat exchanger are respectively connected with a water return main pipe through a second three-way valve; the backwater main pipe is connected with an inlet of a water collector, and an outlet of the water collector is connected with a heat storage water tank and an inlet of a heat pump system.

As a further technical scheme, the soil side heat exchanger comprises a soil side water supply main pipe and a first water return main pipe; the air side heat exchanger comprises an air side water supply main pipe and a second water return main pipe; the air side water supply main pipe is communicated with the soil side water supply main pipe, and a fifth bypass valve is arranged on the communicating pipeline; the second water return main pipe is communicated with the second water return main pipe, and a sixth bypass valve is arranged on the communicating pipeline; a first bypass valve is connected between the inlet side of the soil side water supply main pipe and the first water return main pipe; a third bypass valve is connected between the tail end of the soil side water supply main pipe and the first water return main pipe; a second bypass valve is connected between the inlet side of the air side water supply main pipe and the second water return main pipe; and a fourth bypass valve is connected between the tail end of the air side water supply main pipe and the second water return main pipe.

As a further technical scheme, a temperature sensor and a flow sensor are arranged on the water supply main pipe.

As a further technical scheme, a temperature sensor and a flow sensor are installed on a water return main pipe.

In a second aspect, the present invention further provides a control method for a dual-source subway source heat pump system, including: when the working condition is the parallel working condition of the air side and the soil side, the water supply main pipe of the air side heat exchanger and the water supply main pipe of the soil side heat exchanger are both opened, the first water return main pipe and the second water return main pipe are opened, the first bypass valve, the second bypass valve, the fifth bypass valve and the sixth bypass valve are closed, and the third bypass valve and the fourth bypass valve are opened;

when the working condition is the air side independent working condition; opening a water supply main pipe of the air side heat exchanger, closing a water supply main pipe of the soil side heat exchanger, closing a first water return main pipe, opening a second water return main pipe, opening a fourth bypass valve, and closing other bypass valves;

when the working condition is a soil side independent working condition; opening a water supply main pipe of the soil side heat exchanger, closing a water supply main pipe of the air side heat exchanger, opening a first water return main pipe, closing a second water return main pipe, opening a third bypass valve, and closing other bypass valves;

when the working condition is a series working condition of firstly connecting the soil side and then connecting the air side, the water supply main pipe of the soil side heat exchanger is opened, the water supply main pipe of the air side heat exchanger is closed, the first water return main pipe is opened, the second water return main pipe is closed, the second bypass valve and the fifth bypass valve are opened, and other bypass valves are closed;

when the working condition is a series working condition of firstly connecting the air side and then connecting the soil side, the water supply main pipe of the air side heat exchanger is opened, the water supply main pipe of the soil side heat exchanger is closed, the second water return main pipe is opened, the first water return main pipe is closed, the first bypass valve and the fifth bypass valve are opened, and other bypass valves are closed;

when the water supply main pipe of the air side heat exchanger is opened, the water supply main pipe of the soil side heat exchanger is closed, the first water return main pipe and the second water return main pipe are opened, the first bypass valve, the fourth bypass valve and the fifth bypass valve are opened, and other bypass valves are closed, the flow ratio of the return water of the air side to the soil side can be adjusted by adjusting the opening degree of the valves;

when the water supply main pipe of the air side heat exchanger is closed, the water supply main pipe of the soil side heat exchanger is opened, the first water return main pipe and the second water return main pipe are both opened, the second bypass valve, the third bypass valve and the fifth bypass valve are opened, and when other bypass valves are closed, the flow rate of the return water of the soil side to the air side can be adjusted by adjusting the opening degree of the valves.

In a third aspect, the invention further provides a construction method of the dual-source subway source heat pump system, which comprises the following steps:

firstly, completing the construction of an outer underground diaphragm wall and a bottom plate;

after the construction of the bottom plate is finished, weaving a circle of reinforcement cage of the first layer of the inner side underground continuous wall on the bottom plate close to the outer side underground continuous wall, fixing the heat exchange tubes of the heat exchanger, and fixing the heat exchange tubes meeting the requirements on the reinforcement cage;

the water supply main pipe and the first water return pipe of the air side heat exchanger are arranged in bilateral symmetry, the middle of the water supply main pipe and the first water return pipe are connected through a branch pipe, and the branch pipe of the heat exchange pipe is fixed through a pipe hoop;

a water supply main pipe of the soil side heat exchanger is positioned under the second water return pipe and is sequentially fixed by the water supply main pipe, the soil side heat exchanger branch pipe and the water return pipe of the soil side heat exchanger in sequence;

after the work is finished, pouring concrete; when pouring is carried out, the adjacent inner side continuous wall steel bars and the heat exchange tubes of the layer are finished, the main tubes of the heat exchanger are connected by hot melting or machinery, two ends of the main tube are unsealed before connection, and the air tightness of the main tube is inspected after connection is finished;

according to the process, the concrete layer is poured, the steel bars and the fixed heat exchange tubes are firstly woven, then the concrete is poured, and the supports are detached after the concrete meets the requirements until the top.

The beneficial effects of the above-mentioned embodiment of the present invention are as follows:

(1) the heat exchange tube is used as the front-end heat exchanger for exchanging heat with air and tunnel surrounding rocks, so that the loss of low-grade heat energy in the subway is greatly reduced, and the low-grade heat energy is utilized;

(2) the invention adopts the piston air shaft as the heat exchange place of the air source heat pump, thereby reducing the influence of the heat transfer from the underground space of the subway to the overground space on the overground buildings.

(3) The invention can reduce the heat accumulation of the underground space of the subway and reduce the electric energy consumed by starting the fan due to the heat dissipation of the underground space at night.

(4) The invention changes the limitation that the traditional soil source heat pump can only be laid in tunnel lining or soil, and the heat exchange tube with high heat exchange efficiency is laid in the piston air shaft, so that the soil and the air flowing through the air shaft can be used as cold and heat sources.

(5) The invention can realize multiple operation working conditions of series connection, parallel connection, independent operation and the like of the air side heat exchanger and the soil side heat exchanger; the heat exchanger is divided into two heat exchange tubes before entering the air shaft, wherein the two heat exchange tubes are respectively an air side heat exchanger inlet and a soil side heat exchanger inlet; and bypass valves are arranged between the water supply pipes and the water return pipes of the air side heat exchanger and the soil side heat exchanger in the air shaft and at the positions of the tail end connecting pipes of the two water supply pipes and the two water return pipes, and the flow direction of water is controlled through the working conditions of the bypass valves, the two water supply pipes and the two water return pipes, so that different operation working conditions are realized.

Drawings

The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the application, and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application and not to limit the application.

Fig. 1 is a schematic layout position and structure diagram of a heat exchange pipe water supply and return main pipe of an underground diaphragm wall at the inner side according to a first embodiment of the present invention;

FIG. 2(a) is a top view of an air side heat exchanger arrangement according to a first embodiment of the present invention;

FIG. 2(b) is an isometric view of an air side heat exchanger arrangement according to a first embodiment of the present invention;

FIG. 3(a) is an isometric view of a soil side heat exchanger arrangement according to a first embodiment of the present invention;

FIG. 3(b) is a cross-sectional view of a soil side heat exchanger arrangement according to a first embodiment of the present invention;

fig. 4(a) is a front view of fixing and binding of a heat exchange main pipe according to a first embodiment of the present invention;

FIG. 4(b) is a side view of the fixing and binding of the heat exchange main tubes according to the first embodiment of the present invention;

FIG. 5 is a schematic view of a pipe clamp fixing a branch pipe of a heat exchange pipe according to a first embodiment of the present invention;

FIG. 6(a) is a schematic view of a straight pipe section sleeve hot-melt connection according to a first embodiment of the present invention;

FIG. 6(b) is a schematic view of a thermal fusion connection of a casing of a pipe bending section according to a first embodiment of the present invention

FIG. 7 is a schematic diagram of a system according to a first embodiment of the present invention;

FIG. 8(a) is a schematic view of the inlet side of a water main according to a first embodiment of the present invention;

FIG. 8(b) is a schematic view showing the outlet side of the water main according to the first embodiment of the present invention;

FIG. 9 is a schematic diagram of an implementation method of operation condition control according to a first embodiment of the present invention;

in the figure: 1-inside underground diaphragm wall; 2-water supply main pipe; 3-air side heat exchanger, 3-1 air side water supply main pipe; 4-soil side heat exchanger; 4-1, a water main pipe of the soil side heat exchanger; 5-1-air side heat exchanger manifold; 5-1-a soil side heat exchanger branch pipe, a 6-backwater main pipe, a 6-1 backwater main pipe and a 6-2 backwater main pipe; 7-subway tunnels; 8-1, 8-2, 8-3, 8-4, 8-5 and 8-6 stop valves; 9-binding of the trunk; 10-a reinforcement cage; 11-a pipe hoop; 12-a sleeve; 13-a flow sensor; 14-a temperature sensor; 15-ball valve; 16-an exhaust valve; 17-a pump; 18-a water collector; 19-a water separator; 20-closed water tank; 21-a heat pump unit; 22-a purification device; 23-1 three-way valve, 23-2 three-way valve.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an", and/or "the" are intended to include the plural forms as well, unless the invention expressly state otherwise, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof;

as described in the background art, the present invention provides a dual-source heat pump system for a subway, which is provided to solve the above technical problems.

Example one

The embodiment discloses a dual-source subway source heat pump system, as shown in fig. 7, the system comprises an air-side heat exchanger 3 (convection and heat conduction), a soil-side heat exchanger 4 (heat conduction), a three-way valve 23-1, a three-way valve 23-2, a water separator 18, a water collector 19, a pump 17, a purification device 22, a connecting pipeline, a temperature sensor 14, a flow sensor 13, a heat storage water tank 20, a heat pump system 21, an exhaust valve 16 and a ball valve 15;

the heat storage water tank 20 is connected with the heat pump system 21 in parallel; the heat storage water tank 20 and the outlet of the heat pump system 21 are connected with a pump 17 through a pipeline, the pump 17 is connected with a water separator 18, and the water separator 18 is connected with an air side water supply main pipe 3-1 and a soil side heat exchanger water supply main pipe 4-1 of an air side heat exchanger 3 and a soil side heat exchanger 4 respectively through a heat exchange pipe water supply main pipe 2; the outlet of the air side heat exchanger 3 is connected with a backwater main pipe 6 through a backwater main pipe 6-1; the outlet of the soil side heat exchanger 4 is connected with a backwater main pipe 6 through a backwater main pipe 6-2; the backwater main pipe 6 is connected with the inlet of the water collector 19; the outlet of the water collector 19 is connected to the hot water storage tank 20 and the inlet of the heat pump system 21.

Further, the air-side heat exchanger 3 is as shown in fig. 2(a), 2 (b); comprises an air side heat exchanger main pipe 3-1, a backwater main pipe 6-1 and a branch pipe 5-1; the air side heat exchanger main pipe 3-1 and the backwater main pipe 6-1 are distributed left and right and are connected with each other through a branch pipe 5-1 and a valve of the heat exchange pipe under the operation condition;

further, the soil side heat exchanger 4 is as shown in fig. 3(a) and 3 (b); comprises a soil side heat exchanger main pipe 4-1, a backwater main pipe 6-2 and a branch pipe 5-2; the soil side heat exchanger main pipe 4-1 and the backwater main pipe 6-2 are distributed up and down and are connected with each other through the branch pipe 5-2 and a valve of the heat exchange pipe under the operation condition.

As shown in fig. 8(a), the three-way valve 23-1 is connected to the water supply main pipe 2, the air side water supply main pipe 3-1, and the soil side heat exchanger water supply main pipe 4-1, and the air side water supply main pipe 3-1 and the soil side heat exchanger water supply main pipe 4-1 can be independently opened and closed, so that the three-way valve 23-1 controls the opening or closing of the air side heat exchanger and the soil side heat exchanger.

As shown in fig. 8(b), the three-way valve 23-2 is connected to the water return main pipe 2, the water return main pipe 6-1 and the water return main pipe 6-2, so that the three-way valve 23-2 controls opening and closing of the water return main pipe 6-1 and the water return main pipe 6-2 of the air-side heat exchanger and the soil-side heat exchanger.

Further, the heat exchange tube water supply main pipe 2 is connected with the outlet end of the water pump, the heat exchange tube water supply main pipe 2 is divided into two pipes through a three-way valve 23-1, one is an air side water supply main pipe 3-1, and the other is a soil side water supply main pipe 4-1; the air side and soil side water supply main pipes extend out of the by-pass pipe from the pipe wall along the way to the water return main pipe 6-1 and the water return main pipe 6-2 through the stop valve 8; by-pass pipes with stop valves 8 are used in connection with the air side and the soil side near and at the inlet of the water supply and return main and near and at the outlet of the water return main 6. Specifically, as shown in fig. 9, the water supply main pipe 3 of the air side heat exchanger is connected with the water supply main pipe 4 of the soil side heat exchanger, and a bypass valve 8-5 is arranged on the connecting pipeline; the two backwater main pipes 6-1 are connected with the backwater main pipe 6-2, and a bypass valve 8-6 is arranged on the connecting pipeline; a bypass valve 8-2 and a bypass valve 8-4 are respectively arranged near the inlet side and between the tail end of the water supply main pipe 3 of the air side heat exchanger and the water return main pipe 6-2; a bypass valve 8-1 and a bypass valve 8-3 are arranged near the inlet side and between the tail end of the water supply main pipe 4 of the soil side heat exchanger and the backwater pipe 6-1.

Further, a temperature sensor 14 and a flow sensor 13 are mounted on a pipe connecting the water separator 18 to the inlets of the air-side heat exchanger 3 and the soil-side heat exchanger 4.

Further, a temperature sensor 14 and a flow sensor 13 are also mounted on a pipe connecting outlets of the air-side heat exchanger 3 and the soil-side heat exchanger 4 to the water collector 19.

Further, the embodiment also provides a construction method of the dual-source subway source heat pump system, which comprises the steps of constructing a guide wall of an underground continuous wall, constructing an outer underground continuous wall, constructing concrete of a bottom floor, weaving a reinforcement cage, fixing a heat exchange pipe, constructing an inner underground continuous wall, and connecting a water supply main pipe and a water return main pipe of the heat exchange pipe. The method comprises the following specific steps:

1. early construction

Firstly, conducting guide wall construction, outer side underground continuous wall construction and bottom plate construction on the underground continuous wall, and then weaving a reinforcement cage and fixing a heat exchange tube.

2. Heat exchange tube fixing

Before the heat exchange tube is fixed, the air tightness of the heat exchange tube is checked. After gas with certain pressure is filled into the heat exchange pipes, the two ends of the water supply and return main pipes of the air side heat exchanger 3 and the soil side heat exchanger 4 are sealed. The pressure is equal to 1.5 times of the rated pressure which can be borne by the heat exchange tube, the pressure drop in the tube is less than 5% in 10min, and the qualified heat exchange tube can be fixed after the pressure is reduced to the rated pressure.

The length of the water supply and return main pipe of the heat exchange pipe is matched with the length and width of the air shaft under the condition that the length of the sleeve which is connected by hot melting of the upper sleeve is considered, so that the sleeve can be connected by hot melting at the corner.

As shown in figure 1, the fixing of the water supply and return main pipe of the heat exchange pipe starts from the upper part of the subway tunnel 7, and the water supply and return main pipe of the heat exchange pipe is in a double-helix structure along the underground continuous wall 1 on the inner side of the air shaft and is similar to DNA.

The vertical steel bars and the horizontal steel bars positioned at the lower part of the water supply and return main pipe of the heat exchange pipe are woven and welded, then the water supply and return main pipe of the heat exchanger is bound at the welding point of the steel reinforcement cage 10 as shown in figure 4, and the water supply and return main pipe of the heat exchange pipe is fixed at the same time.

After the banding is completed, the air-side heat exchanger branch pipes 8 are in a mesh shape in a plan view of the air shaft, as shown in fig. 2(a) and (b). As shown in fig. 3(a) and 3(b), the arrangement of the water supply and return main pipe and branch pipe 5 for the soil side heat exchanger is shown.

As shown in fig. 4(a) and 4(b), the branch tubes 5 of the heat exchange tube are fixed by pipe collars 11, and the pipe collars 11 are arranged at intervals. The pipe hoop 11 should ensure that the heat exchange pipe branch pipe 5 generates small displacement in the maximum piston wind state, and the rigidity limit requirement and the strength limit requirement of the heat exchange pipe branch pipe 5 when the wind speed in the air shaft is maximum should be met.

After the heat exchange tube is fixed, weaving and welding of the upper part of the water supply and return main tube of the heat exchange tube to the reinforcement cage in a horizontal manner are sequentially carried out.

3. Construction of inside underground continuous wall

The edge of the reinforcement cage 10 should be shielded, a certain speed should be maintained in the process of pouring concrete, the speed cannot be too high or too low, and the pouring process must not be interrupted. The middle of the inner underground continuous wall 1 needs to be added with a water stop to stop water penetration. The inner underground continuous wall 1 is poured one layer at first and one layer at a time, and after one layer is poured, the next layer is poured until the uppermost layer.

4. Connection of water supply and return main pipe of heat exchange pipe

Before the heat exchange pipe supplies water and returns water to the main pipe, the two ends of the heat exchange pipe are firstly unsealed.

The heat exchange tube supplies the water return main pipe end to end connection, and the water supply main pipe of soil side heat exchanger connects water supply main pipe 25, and the water supply main pipe 3 of air side heat exchanger connects water supply main pipe 26, and heat exchange tube return water main pipe 6 connects return water main pipe 6 to seal the end of main pipe 6.

The water supply and return main pipes of the heat exchange pipe are connected by a sleeve 12 in a hot melting way. As shown in fig. 6(a) and 6(b), the straight pipe sections are connected by straight sleeves, and the bends are connected by elbow sleeves. The connection was checked for hermeticity after the connection was completed. And (3) filling gas with a certain pressure into the tube, wherein the pressure is equal to 1.5 times of the rated pressure which can be borne by the heat exchange tube, the pressure drop in the tube is less than 5% in 10min, checking after the pressure is reduced to the rated pressure, and pouring the concrete of the inner underground continuous wall 1 after the pressure is checked to be qualified.

And then fixing the water supply and return main pipes of the heat exchange pipes and weaving the reinforcement cage 10 according to the construction sequence of the underground continuous wall of the air shaft, connecting the water supply and return main pipes of the heat exchange pipes, pouring concrete of the underground continuous wall 1 on the inner side, and constructing layer by layer until the uppermost layer.

The embodiment also discloses a control operation strategy of the dual-source subway source heat pump system, and according to the connection relation shown in fig. 9, the specific control method is as follows:

when the water supply main pipe 3-1 of the air side heat exchanger and the water supply main pipe 4-1 of the soil side heat exchanger are both opened, the water return main pipe 6-1 and the water return main pipe 6-2 are opened, the bypass valve 8-1, the bypass valve 8-2, the bypass valve 8-5 and the bypass valve 8-6 are closed, and the bypass valve 8-3 and the bypass valve 8-4 are opened, the working condition is a parallel working condition of the air side and the soil side; when the water supply main pipe 3-1 of the air side heat exchanger is opened, the water supply main pipe 4-1 of the soil side heat exchanger is closed, the water return main pipe 6-1 is closed, the water return main pipe 6-2 is opened, the bypass valve 8-4 is opened, and other bypass valves are closed, the working condition is an air side independent working condition; when the water supply main pipe 4-1 of the soil side heat exchanger is opened, the water supply main pipe 3-1 of the air side heat exchanger is closed, the water return main pipe 6-1 is opened, the water return main pipe 6-2 is closed, the bypass valve 8-3 is opened, and other bypass valves are closed, the working condition is a soil side independent working condition; when a water supply main pipe 4-1 of the soil side heat exchanger is opened, a water supply main pipe 3-1 of the air side heat exchanger is closed, a water return main pipe 6-1 is opened, a water return main pipe 6-2 is closed, a bypass valve 8-2 and a bypass valve 8-5 are opened, other bypass valves are closed, and the working condition is a series working condition of firstly the soil side and then the air side; when the water supply main pipe 3-1 of the air side heat exchanger is opened, the water supply main pipe 4-1 of the soil side heat exchanger is closed, the water return main pipe 6-2 is opened, the water return main pipe 6-1 is closed, the bypass valve 8-1 and the bypass valve 8-5 are opened, other bypass valves are closed, and the working condition is a series working condition of firstly connecting the air side and then connecting the soil side; when the water supply main pipe 3-1 of the air side heat exchanger is opened, the water supply main pipe 4-1 of the soil side heat exchanger is closed, the water return main pipe 6-1 and the water return main pipe 6-2 are opened, the bypass valve 8-1, the bypass valve 8-4 and the bypass valve 8-5 are opened, and other bypass valve is closed, the flow ratio of the return water at the air side to the soil side can be adjusted by adjusting the opening degree of the valves; when the water supply main pipe 3-1 of the air side heat exchanger is closed, the water supply main pipe 4-1 of the soil side heat exchanger is opened, the water return main pipe 6-1 and the water return main pipe 6-2 are both opened, the bypass valve 8-2, the bypass valve 8-3 and the bypass valve 8-5 are opened, and other bypass valve is closed, the flow ratio of the return water at the soil side to the air side can be adjusted by adjusting the opening degree of the valves.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.