System for storing terrestrial heat to shallow underground layer by using air heat

Abstract

The utility model discloses a system for storing terrestrial heat to an underground shallow layer by utilizing air heat, which belongs to the technical field of clean energy heat exchange equipment and comprises a heat absorption device and an underground buried pipe vertically buried in the shallow layer soil, and the heat absorption device is communicated with the underground buried pipe through a pipeline. The heat absorption device is used for absorbing heat in air and transferring the heat to a medium, the pipeline is provided with a circulating pump, and the underground buried pipe is of a U-shaped pipe structure and is used for transferring the heat in the medium to shallow soil. Heat in the air is absorbed through the heat absorption equipment, the heat absorption medium is conveyed to the underground buried pipe through the pipeline, the heat is transferred to the shallow soil through the underground buried pipe, and recycling of terrestrial heat is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of clean energy heat exchange equipment, and particularly relates to a shallow geothermal heat storage system utilizing air heat. Background Art

[0002] Using shallow geothermal heat for heating has the advantage of low cost, but the problem is that after two or three years of continuous heating, the underground heat loss cannot be recovered, forming a cold pool, which makes it impossible to recycle. If underground heat is taken in winter and supplemented by solar energy in summer, the investment is very high, the land area is large, and the cost recovery period is too long. In the hot summer in Northwest China, the outdoor air temperature can reach about 40℃. After practical exploration, we proposed a system that uses air heat to store shallow geothermal heat underground. Utility Model Content

[0003] The purpose of the utility model is to provide a shallow geothermal heat storage system using air heat, aiming to solve the problems existing in the prior art in the above-mentioned background technology.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A shallow geothermal heat storage system utilizing air heat comprises a heat absorbing device and an underground pipe vertically buried in the shallow soil. The heat absorbing device is connected to the underground pipe through a pipeline. The heat absorbing device is used to absorb heat in the air and transfer it to a medium. The pipeline is provided with a circulating pump. The underground pipe adopts a U-shaped pipe structure and is used to transfer heat in the medium to the shallow soil underground.

[0006] Furthermore, the heat absorption device includes a support frame, a surface cooler and a fan, the support frame has a bottom plate, a plurality of support rods are arranged at intervals around the top surface of the bottom plate, connecting plates are arranged on both sides of the support rods, the connecting plates between adjacent support rods are aligned and parallel, and cross bars are arranged on the tops of adjacent support rods, the surface cooler is arranged between the aligned and parallel connecting plates, the fan is arranged on the top of the support frame, and the fan is closed and connected to the cross bars around. The air enters the heat absorption device along the surface cooler, and is fully heat-exchanged with the surface cooler before being discharged through the top fan.

[0007] Furthermore, the pipeline is provided with a soft water tank for buffering the heat absorption expansion of the medium and replenishing the medium.

[0008] Furthermore, it also includes a temperature sensor and a controller. The temperature sensor, the fan and the circulation pump are electrically connected to the controller respectively. When the air temperature is ≥18°C, the controller starts the fan and the circulation pump.

[0009] Furthermore, the underground buried pipe is buried vertically in the ground, and the burial depth ranges from 120 to 150 m.

[0010] Furthermore, the circulation pump is arranged in the pipeline in the direction of medium flow from the underground buried pipe to the heat absorption device.

[0011] Furthermore, the base plate is provided with supporting legs and an inspection entrance, and the inspection entrance is used to enter the interior to inspect the heat absorbing device.

[0012] Furthermore, a protective net is arranged on the outside of the surface cooler, and the protective net is connected to the cross bar and the bottom plate respectively.

[0013] Furthermore, a plurality of surface coolers are vertically arranged between the parallel connection plates, the surface coolers are sequentially connected to form a group of surface coolers, and a support plate is arranged between the parallel connection plates, the support plate is used to support the surface coolers. The support plate separates and supports the surface coolers, which facilitates the maintenance and replacement of a single surface cooler.

[0014] Furthermore, the medium is water.

[0015] Compared with the shortcomings and deficiencies of the prior art, the utility model has the following beneficial effects.

[0016] 1. The utility model provides a shallow geothermal heat storage system using air heat. A heat absorption device absorbs heat from the air. Under the action of a circulating pump, the medium after absorbing heat is transported along a pipeline to an underground pipe buried in the shallow soil layer. The heat in the medium is transferred to the shallow underground soil through the underground pipe to recover underground thermal energy, which is helpful for recycling geothermal energy. The shallow geothermal heat storage system consumes less resources and is easy to control.

[0017] 2. In the shallow geothermal heat storage system, the heat absorption device adopts a combined structure of a fan, a surface cooler and a support frame, so that the external air enters the heat absorption device through the surface cooler, so that the air and the surface cooler are fully in contact for heat exchange, and the fan drives the air after heat exchange to be discharged. The heat absorption device has the characteristics of small footprint, low device cost, low operating cost and long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The utility model is a schematic flow diagram of a shallow geothermal heat storage system utilizing air heat.

[0019] Figure 2 It is a structural schematic diagram of a heat absorption device provided with a surface cooler in the utility model.

[0020] Figure 3 It is a schematic diagram of the top view of the heat absorption device in the utility model.

[0021] Figure 4 It is a schematic diagram of the control flow of the controller in the utility model.

[0022] In the figure: 1-heat absorption device; 2-underground buried pipe; 3-circulation pump; 4-soft water tank; 5-bottom plate; 6-support rod; 7-connecting plate; 8-surface cooler; 9-fan; 10-support plate; 11-support leg; 12-protective net; 13-second pipeline; 14-cross bar; 15-first pipeline. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0024] Reference Figure 1 A geothermal heat storage system utilizing air heat to store heat in a shallow underground layer comprises a heat absorption device 1 for absorbing heat from the air and transferring it to a medium in a pipeline, an underground buried pipe 2 for transferring heat from the medium in the pipeline to the shallow underground soil, the heat absorption device 1 and the underground buried pipe 2 are connected through a pipeline to form a circulation system, the pipeline is provided with a circulation pump 3 for promoting the circulation of the medium to absorb and release heat, so as to form a geothermal heat storage system utilizing air heat to store heat in a shallow underground layer, thereby absorbing heat from the air and replenishing it to the shallow underground layer.

[0025] Reference Figure 2 and Figure 3 The heat absorption device 1 adopts a hollow box structure, including a support frame, a cooler 8 and a fan 9. The support frame includes a bottom plate 5 and support rods 6 arranged around the top surface of the bottom plate 5. Connecting plates 7 are arranged on both sides of the support rods 6. The connecting plates 7 between adjacent support rods 6 are aligned and parallel to each other. The cooler 8 is arranged between the aligned and parallel connecting plates 7. A cross bar 14 is arranged between the tops of adjacent support rods 6. The cross bar 14 and the support rods 6 form a frame structure. The fan 9 is located at the top of the heat absorption device 1. The fan 9 is closed and connected with the cross bars 14 around. Preferably, the fan 9 adopts an axial flow fan. The bottom plate 5 is used to block air from entering along the bottom of the heat absorption device 1. Under the action of the fan 9, the external air passes through the cooler 8 and enters the interior of the heat absorption device 1. After heat exchange, it is discharged through the fan 9, so that the cooler 8 and the air can fully exchange heat.

[0026] A horizontal support plate 10 is arranged between the relatively parallel connecting plates 7. The support plate 10 is used to support the surface cooler 8 and is also beneficial to increasing the stability of the support frame structure. The surface coolers 8 on the same side that are positioned up and down are connected in sequence to form a group of surface coolers 8. The heat absorption device 1 can be provided with multiple groups of surface coolers 8, and the multiple groups of surface coolers 8 are surrounded to form the vertical side wall of the heat absorption device 1. The heat absorption device 1 is provided with a liquid inlet pipe and a liquid outlet pipe. The liquid inlet pipe is respectively connected to the liquid inlet of each group of surface coolers, and the liquid outlet pipe is respectively connected to the liquid outlet of each group of surface coolers. The pipeline between the heat absorption device 1 and the underground buried pipe 2 includes a first pipeline 15 and a second pipeline 13. The liquid outlet pipe is connected to the liquid inlet of the underground buried pipe 2 through the first pipeline 15 to transport the heat absorption medium to the underground buried pipe 2. The liquid inlet pipe is connected to the liquid outlet of the underground buried pipe 2 through the second pipeline 13 to transport the heat-released medium to the heat absorption device 1.

[0027] The underground pipe 2 is vertically buried underground. A group of underground pipes 2 adopts a U-shaped structure. The medium after absorbing heat enters the underground pipe 2. Under the action of the circulating pump 3, it flows downward along the underground pipe 2, moves to the U-shaped bend at the bottom of the underground pipe 2 and returns to flow upward. During the flow of the medium in the underground pipe 2, the heat is transferred to the shallow underground soil through the pipe wall of the underground pipe 2, thereby replenishing heat to the shallow underground soil. The shallow underground soil mainly refers to the soil within 200 meters underground. The buried depth of the underground pipe 2 is preferably between 120-150m. The underground pipe 2 adopts PE hot melt pipe, which has good pressure resistance and thermal conductivity, which is conducive to ensuring system operation and heat exchange.

[0028] In one embodiment, the circulation pump 3 is arranged in the second pipeline 13, and the medium in the underground buried pipe 2 is drawn to the heat absorption device 1 through the circulation pump 3. Compared with setting the circulation pump 3 in the first pipeline 15, it is beneficial to reduce the pressure on the underground buried pipe 2, thereby improving the stability of the operation of the shallow geothermal heat storage system.

[0029] In one embodiment, a soft water tank 4 is provided between the heat absorption device 1 and the underground buried pipe 2. The soft water tank 4 is connected to the heat absorption device 1 and the second buried pipe 2 respectively through the first pipeline 15. The soft water tank 4 is used to buffer the heat absorption expansion of the medium and facilitate the replenishment of the medium into the system. The medium can be water.

[0030] In one embodiment, the heat absorption device 1 is provided with a protective net 12, and the protective net 12 is used to protect the surface cooler 8 and prevent the surface cooler 8 from being damaged by external forces.

[0031] In one embodiment, a support leg 11 is provided at the bottom of the base plate 5, and a maintenance entrance (not shown in the figure) is provided at the base plate 5. The maintenance entrance is provided with an opening and closing door to facilitate maintenance personnel to enter the heat absorption device 1 through the maintenance entrance for maintenance.

[0032] In one embodiment, referring to Figure 4When the air temperature is ≥18℃, the circulation pump and the fan start working, the heat absorption device 1 starts, and the air heat is used to circulate and absorb the heat in the air to the shallow geothermal heat storage system underground, and transfer the heat to the shallow soil. The heat absorption device 1 is provided with a temperature sensor and a controller, and the controller is electrically connected to the temperature sensor, the fan 9 and the circulation pump 3 respectively. The temperature sensor is used to monitor the air temperature. When the air temperature is ≥18℃, the temperature sensor transmits a signal to the controller. After receiving the signal, the controller starts the fan 9 and the circulation pump 3. When the temperature is <18℃, the controller controls the fan and the circulation pump to stop, thereby realizing the automatic control of the shallow geothermal heat storage system underground by using air heat. It is suitable for the spring, summer and autumn seasons in northern my country. In winter, due to the low temperature, the shallow geothermal heat storage system underground by using air heat can be shut down and the medium in the pipeline can be discharged.

[0033] When the shallow underground geothermal heat storage system utilizing air heat is used, when the temperature sensor monitors that the air temperature is ≥18°C, the controller starts the fan 9 and the circulation pump 3. Under the action of the fan 9, the air outside the heat absorption device 1 penetrates along the surface cooler 8 arranged around the heat absorption device 1. After the hot air fully contacts and exchanges heat with the surface cooler 8, it is discharged through the fan 9 on the top of the heat absorption device 1. After the medium in the surface cooler 8 absorbs heat, it flows through the soft water tank 4 under the action of the circulation pump 3 and then flows into the underground buried pipe 2. During the flow of the underground buried pipe 2, the heat in the medium is transferred to the shallow underground soil through the pipe wall, thereby completing the heat storage of the shallow underground soil.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A shallow geothermal heat storage system using air heat, characterized in that: The invention comprises a heat absorbing device (1) and an underground buried pipe (2) vertically buried in shallow soil. The heat absorbing device (1) is connected to the underground buried pipe (2) via a pipeline. The heat absorbing device (1) is used to absorb heat in the air and transfer it to a medium. The pipeline is provided with a circulation pump (3). The underground buried pipe (2) adopts a U-shaped pipe structure and is used to transfer heat in the medium to the shallow soil underground.

2. The shallow geothermal heat storage system using air heat as claimed in claim 1 is characterized in that: The heat absorption device (1) comprises a support frame, a surface cooler (8) and a fan (9), wherein the support frame has a bottom plate (5), a plurality of support rods (6) are arranged at intervals around the top surface of the bottom plate (5), connecting plates (7) are arranged on both sides of the support rods (6), the connecting plates (7) between adjacent support rods (6) are aligned and parallel, and a cross bar (14) is arranged on the top of adjacent support rods (6), the surface cooler (8) is arranged between the aligned and parallel connecting plates (7), and the fan (9) is arranged on the top of the support frame, and the fan (9) is closed and connected to the cross bar (14) around.

3. The shallow geothermal heat storage system using air heat as claimed in claim 1 is characterized in that: The pipeline is provided with a soft water tank (4) for buffering the heat absorption expansion of the medium and replenishing the medium.

4. The shallow geothermal heat storage system using air heat as claimed in claim 2 is characterized in that: It also includes a temperature sensor and a controller. The temperature sensor, the fan (9) and the circulation pump (3) are electrically connected to the controller respectively. When the air temperature is ≥18°C, the controller starts the fan (9) and the circulation pump (3).

5. The shallow geothermal heat storage system using air heat as claimed in claim 1 is characterized in that: The underground buried pipe (2) is buried vertically underground, and the buried depth ranges from 120 to 150 m.

6. The shallow geothermal heat storage system using air heat as claimed in claim 1 is characterized in that: The circulation pump (3) is arranged in a pipeline in the direction in which the medium flows from the underground buried pipe (2) to the heat absorption device (1).

7. The shallow geothermal heat storage system using air heat as claimed in claim 2 is characterized in that: The bottom plate (5) is provided with supporting legs (11) and an inspection entrance, wherein the inspection entrance is used to enter the interior to inspect the heat absorbing device (1).

8. The shallow geothermal heat storage system utilizing air heat as claimed in claim 2, characterized in that: A protective net (12) is arranged outside the surface cooler (8), and the protective net (12) is connected to the cross bar (14) and the bottom plate (5) respectively.

9. The shallow geothermal heat storage system using air heat as claimed in claim 2, characterized in that: A plurality of surface coolers (8) are arranged vertically between the parallel connection plates (7); the surface coolers (8) are connected in sequence to form a group of surface coolers (8); and a support plate (10) is arranged between the parallel connection plates (7); the support plate (10) is used to support the surface coolers (8).

10. The shallow geothermal heat storage system using air heat as claimed in claim 4, characterized in that: The medium is water.

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