KR101160486B1

KR101160486B1 - Ground-loop heat exchanger for Ground heat pump

Info

Publication number: KR101160486B1
Application number: KR1020100043598A
Authority: KR
Inventors: 김진상
Original assignee: 김진상
Priority date: 2010-05-10
Filing date: 2010-05-10
Publication date: 2012-06-28
Also published as: KR20110124035A

Abstract

The present invention relates to an underground heat exchanger of a geothermal heat pump. The present invention is formed of a flexible material so that the circulation pipe inserted into the well can be folded to be pulled up by a reel so that the lifting of the circulation pipe is easy and the space required for lifting the circulation pipe is small, such as a basement. An underground heat exchanger can also be installed. In addition, as the well is installed inside the manhole, it is possible to facilitate maintenance work of the underground heat exchanger without digging.

Description

Ground-loop heat exchanger for ground heat pump

The present invention relates to a geothermal heat pump system that performs cooling and heating using groundwater or geothermal heat as a heat source, and more particularly, to an underground heat exchanger of a geothermal heat pump system.

The geothermal method uses geothermal power generation to generate electricity by using high temperature heat in the ground, direct geothermal method using geothermal heat directly like hot spring water, and uses a heat pump to perform heating and cooling by using low temperature geothermal power. Geothermal pumps can be divided into two types.

Geothermal heat pumps use groundwater and geothermal heat as heating and cooling sources. Geothermal heat is a stable heat source with little temperature change throughout the year, making it suitable for residential and commercial use. . As a kind of underground use, a geothermal heat pump that is widely used recently uses relatively shallow geothermal heat, and forms a well of 400 to 500 m deep inside a well-developed rock bed and installs a heat exchanger inside the well. It is a technology for heating and cooling. The structure has been shown in Korean Utility Model Registration No. 0371813 and Patent No. 10-0675257 filed by the applicant.

Among the geothermal heat pumps, the semi-open type, also known as standing column W1ell heat exchanger is a method in which heat is directly exchanged between rock and groundwater using accumulated water in a narrow and long well. Compared to an open heat exchanger that uses ground water directly or a sealed heat exchanger that uses a U-shaped tube inserted vertically, it is gradually spread in favor of problems such as securing installation space, installation cost, pollution, product life, and maintenance of the well. This is an expanding trend.

The standing column heat exchanger as described above embeds groundwater circulation pipes (hereinafter, referred to as circulation pipes) inside the wells formed by drilling rock layers, pulls the groundwater collected in the wells to the ground, heat exchanges them with heat exchangers, and then circulates them again. It uses the energy absorbed during the process of returning to the inside of the well through the pipe and uses it as energy of the heating and cooling system.

Here, the circulation pipe generally uses a pipe made of PVC (Polyvinyl Chloride). However, PVC contains chlorine, an ozone depleting substance, and is recognized as a non-environmental material due to the generation of dioxin in the manufacturing process, so it is environmentally friendly like PE (polyethylene) in sewage pipes that have been widely used for a long time. It is being replaced with phosphorus material. Among PE pipes, HDPE (High Density Polyethylene) is widely used for water and sewage and gas pipes. And since PVC pipe is weak and hard, it is generally made of 4 ~ 6m in length, so it is generally used to connect several short pipes with adhesive to form a circulation pipe from the top to the bottom of the well, which has a depth of 400 ~ 500m. to be.

As described above, the circulation pipe connecting the plurality of PVC pipes by using an adhesive or a mechanical connecting device has about 100 joints, and thus, the work process is complicated, and when the circulation pipe is installed or used, the circulation pipe is defective. There is a fear that cracks or holes are generated in the middle of the tube, thereby reducing the performance of the geothermal heat pump.

In addition, during the installation or use of the circulation pipe, cracks or holes are generated, and inspection is necessary, or in order to remove foreign substances (rock and rock fragments, sand grains, etc.) naturally occurring inside the well due to long-term use. If the air surging is carried out every 5 years, the underwater heat exchanger, such as the PVC pipe is cut off or the joint is pulled out while the underwater pumps, pipes, and motor cables, etc. There is a problem that inspection and maintenance are not easy.

In view of this, in recent years, a technology (utility model registration No. 20-0419540) in which a circulation pipe is improved to PE material for the inspection and repair of underground heat exchangers has been introduced. This technology installs a submersible pump that sucks deep groundwater that maintains a constant temperature collected in the well, and is positioned relatively upstream within the well.The discharge end of the circulating pipe passing through the ground heat exchanger It extends long to a position close to the bottom of the well so that it can flow out to the bottom of the bottom. The circulation pipe is made of a PE material having flexibility and excellent tensile strength, and the traction wire is clamped along the longitudinal direction of the circulation pipe so that the circulation pipe can be pulled out of the well.

However, as the conventional underground heat exchanger as described above, the circulation pipe inserted into the well is more flexible than the hard PVC or PVC, but to some extent made of a hard PE material, it is difficult to lift the circulation pipe out of the well during maintenance work. Due to the difficulty in lifting the circulated pipes, a fairly large work space is required, which makes it difficult to install underground heat exchangers in individual buildings.

In addition, conventionally, since the connection portion connecting the underground heat exchanger and the ground heat exchanger is usually buried in the ground, when performing maintenance work, the surrounding area of the ground heat exchanger should be dug up after digging the ground, and after completion of work, the ground must be buried again. There was a problem that it becomes more difficult to periodically perform the maintenance work of the heat exchanger.

An object of the present invention is not only easy to lift the circulation pipe for the installation work and maintenance of the circulation pipe is easy, but also to install the underground heat exchanger in individual buildings by reducing the space for lifting the circulation pipe lifted from the well It is to provide an underground heat exchanger of a geothermal heat pump.

It is another object of the present invention to provide an underground heat exchanger of a geothermal heat pump that can be easily separated from the connection portion between the underground heat exchanger and the ground heat exchanger.

In order to achieve the object of the present invention, it includes a circulation pipe is inserted in the longitudinal direction of the well drilled so that the groundwater in the underground rock layer circulated between the well and the ground heat exchanger; The circulation pipe is provided with an underground heat exchanger of a geothermal heat pump made of a collapsible material whose inner circumferential surface may overlap when the ground water is not filled.

Here, the circulation pipe may be formed of a waterproof material of the outer circumferential surface and the inner circumferential surface, and woven fiber material between the outer circumferential surface and the inner circumferential surface.

The circulation pipe may be made of one of a polyurethane built-in hose or a rubber built-in hose.

The circulation pipe may include a weight having a specific gravity greater than that of water, and the weight may have a hole communicating the inside and the outside of the circulation pipe.

And, the upper side of the well is provided with a manhole for accommodating the upper side of the well, the ground wall of the manhole is coupled through the groundwater pipe connected to the ground heat exchanger, the top of the well is provided with a cover plate covering the well In addition, the cover plate may be provided with a fixed connecting pipe detachably connected to the circulation pipe, and an intermediate connecting pipe may be detachably connected between the groundwater pipe and the fixed connecting pipe.

And, the circulation pipe is composed of an inlet side circulation pipe into which the groundwater flows from the well and an outlet side circulation pipe through which the groundwater flows into the well, and the outlet side circulation pipe is disposed on the bottom surface of the well more than the inlet circulation pipe. It can be installed to be closer.

The underground heat exchanger of the geothermal heat pump according to the present invention is formed of a flexible material such that the circulation pipe inserted into the well can be folded, and can be wound up and reeled up so that the lifting of the circulation pipe is easy, and even in a narrow work space, It is easy to lift the installed circulation pipe, so it is possible to install underground heat exchanger in the basement of individual buildings.

In addition, since the well is installed inside the manhole, maintenance work of the underground heat exchanger can be facilitated without digging.

1 is a cross-sectional view showing the underground heat exchanger structure of the embodiment of the present invention,
Figure 2 is a cross-sectional view showing the upper end in the underground heat exchanger according to Figure 1,
3 is a cross-sectional view taken along the line 'Ι-Ι' of FIG. 2;
Figure 4 is an enlarged view showing the outlet end of the outlet side circulation pipe in the underground heat exchanger according to Figure 1,
5 is a cross-sectional view showing an exploded upper end in the underground heat exchanger according to FIG.
6 and 7 are schematic views showing examples of lifting the circulation pipe in the underground heat exchanger of the present invention.

The ground heat exchanger of the geothermal heat pump system according to the present invention will be described in detail based on the embodiment shown in the accompanying drawings.

1 is a cross-sectional view showing an underground heat exchanger structure according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing an upper end portion of the underground heat exchanger according to FIG. 1, FIG. 1 is an enlarged view illustrating the outlet end of the outlet side circulation pipe in the underground heat exchanger according to FIG. 1, and FIG. 5 is a cross-sectional view of the underground heat exchanger according to FIG.

As shown in FIG. 1, the underground column heat exchanger of the standing column well type used in the present invention is mainly applied to a well-developed region, and the groundwater W1 is accumulated in the rock by drilling the rock layer 1. 100), using the ground water (W) accumulated in the inside of the well (100) is used to absorb the heat of the rock constituting the well or to store the heat in the rock.

That is, the underground heat exchanger according to the embodiment of the present invention and the well 100 obtained by drilling the rock bed 1, the inlet side circulation pipe 210 is installed inside the well 100 and circulates the ground water (W) and the outlet A submersible pump (220) and the inside of the inlet side of the circulation pipe (200) is provided with an underwater pump (300) for pumping groundwater (W) accumulated in the well (100), and the upper end of the well (100) It includes a manhole 400 is provided with a predetermined internal space (S) to be filled with a predetermined depth from the ground.

Since the well 100 is formed of a well 100 without casing except for the upper end, the groundwater W1 flowing into the upper or lower portion of the rock layer 1 is directly contacted with the rock and naturally held therein. do.

And, the upper end of the well 100 is open and close and is provided with a cover plate 110 to prevent contamination. The open plate 110 is installed in the transverse direction on the top of the casing 101 having a predetermined height from the bottom surface of the manhole 400 is formed to cover the entire well. The casing 101 is formed in a cylindrical shape and an extended flange portion is formed by welding or integrally formed at its upper end so as to be fastened to the cover plate 110.

The first fixing connecting tube 111 and the second fixing connecting tube 112 penetrate through the longitudinal direction of the well, respectively, and are welded to the cover plate 110. In addition, a plurality of fastening holes (unsigned) are formed at the edge of the cover plate 110 to be bolted to the flange of the case.

The first fixed connecting tube 111 and the second fixed connecting tube 112 is formed of a metal tube having a predetermined strength to maintain the shape, the first fixed connecting tube 111 and the second fixed connecting tube ( 112 is provided with couplings 215 and 225 at both ends of the inlet circulating pipe 210 and the outlet circulating pipe 220, respectively, and the first intermediate connecting pipe 510 and the first one. 2 are detachably coupled to the couplings 511 and 521 of the intermediate connecting pipe 520, respectively.

The first intermediate connecting pipe 510 and the second intermediate connecting pipe 520 are groundwater passing through the main wall of the manhole 400 which will be described later with the first fixed connecting pipe 111 and the second fixed connecting pipe 112. Removably connecting to the pipes (3) (4), respectively, the first intermediate connecting pipe 510 and the second intermediate connecting pipe 520 are each formed to be bent.

One end of the first intermediate connecting pipe 510 and the second intermediate connecting pipe 520 is in the longitudinal direction, that is, the longitudinal direction of the first well connected to the first fixed connecting pipe 111 and the second fixed connecting pipe 112, respectively. While the other end thereof is connected to the first ground water pipe 3 and the second ground water pipe 4, respectively. Accordingly, the first intermediate connecting pipe 510 and the second intermediate connecting pipe 520 are bent at approximately 90 ° so that both ends thereof are the fixed connecting pipes 111 and 112 and the groundwater pipes 3 and 4. Is connected to each. Here, both ends of the first intermediate connecting pipe 510 and the second intermediate connecting pipe 520 may be detachably coupled to the fixed connecting pipes 111 and 112 and the groundwater pipes 3 and 4. Couplings (511, 512) (521, 522) are preferably provided. Of course, the couplings may be installed in opposite tubes to which the intermediate connecting tubes are coupled.

The inlet side circulation pipe 210 and the outlet side circulation pipe 220 may be formed to have the same inner diameter and length, but that the foreign material such as gravel or sand in the well flows into the inlet side circulation pipe 210. In order to prevent or to lengthen the heat exchange length sufficiently, the inlet side circulation pipe 210 is preferably shorter than the length of the outlet side circulation pipe 220. That is, the lower end of the inlet side circulation pipe 210 is formed to be disposed at a relatively higher position than the upper half of the well 100, precisely the lower end of the outlet side circulation pipe 220, while the outlet side circulation pipe 220 The bottom of the) is to spray the groundwater into the inside of the well 100, so that there is little risk of foreign matter inflow, and is disposed to extend long near the bottom surface of the well 100 so that the heat exchanged ground water is discharged to the bottom of the well It may be desirable.

Both the inlet side circulation pipe 210 and the outlet side circulation pipe 220 may be formed of a flexible material, that is, a PE material having flexibility and elasticity rather than PVC. However, the relatively long outflow side circulation pipe 220 among the inflow side circulation pipe 210 and the outflow side circulation pipe 220 may facilitate the lifting operation and facilitate the management of the lifted pipe. It may be desirable to form a more flexible material than the material.

For example, the outlet side circulation pipe 220 is a fire-fighting material made of a foldable material such as a polyurethane built-in hose or a rubber built-in hose that can be easily folded while the inner circumferential surface is in contact with each other when the ground water is not filled It may be desirable to form a hose.

Here, the fire hose used as the outlet side circulation pipe 220 may be made of three layers as shown in FIG. For example, the inner circumferential surface and the outer circumferential surface of the outflow side circulation tube 220 are formed with waterproof layers 221 and 222 made of waterproof materials, respectively, and the heat insulation layer 223 is provided to increase thermal insulation between the inner circumferential surface and the outer circumferential surface. Is formed. The waterproof layers 221 and 222 may be formed of polyethane, rubber, or the like, and the heat dissipating layer 223 may be formed of a fiber material having a large amount of air space to increase thermal insulation performance. In particular, when the heat insulating layer 223 is used as a fiber material, the strength of the circulation pipe can be increased, thereby preventing damage due to long-term use.

And, the lower end of the inlet side circulation pipe 210 and the outlet side circulation pipe 220 is provided with a plurality of through-holes 230, 240 are provided with a plurality of through holes, respectively.

As shown in FIG. 4, the hole pipes 230 and 240 are formed in a cylindrical shape with a closed lower end, and a plurality of through holes 231 and 241 are formed in a main wall thereof. The through holes 231 and 241 may be formed in a circular shape. However, the through holes 231 and 241 may have a long long hole shape in the length direction as shown in FIG.

In addition, fastening portions 232 and 242 for fastening the weights 250 and 260 which will be described later may be formed at the lower ends of the perforated pipes 230 and 240. However, the weights 250 and 260 may be manufactured by integrally molding with the hole pipes 230 and 240 without fastening to the hole pipes 230 and 240 separately.

The inlet circulating pipe 210 and the outlet circulating pipe 220, in particular the outlet circulating pipe 220 has a long length and the specific gravity of the water despite being locked to near the bottom surface of the well 100 It may be made of lighter polyethane and fibers so that it may be difficult to submerge into the groundwater accumulated in the well 100 during the installation process, so that a weight having a predetermined weight is installed at the bottom of the outlet side circulation pipe 220. It may be desirable. Here, although not shown in the drawings, the weight on the inlet side circulation pipe 210 may not be installed. That is, in the case of the inflow side circulation pipe 210, the inflow side circulation pipe 210 is straightened so that the groundwater can be smoothly introduced even if a separate weight is not installed as the submersible pump 300 is installed at the end thereof. Can be.

The weight 230 is generally made of a material that is heavier than water can be used. In addition, the lower end of the outlet side circulation pipe 220 may be installed using a variety of methods, such as mounting by hanging a hole or the like. The through hole may be formed in the outlet side circulation pipe 220, but in this case, since the through hole may be torn by the weight of the weight, it may be desirable to form a long rectangle or ellipse in the vertical direction without the notch. .

And as the material of the weight 230, it may be preferable to use a corrosion-resistant metal or coating a corrosion-resistant material even if using a concrete or a metal.

On the other hand, the inlet side circulation pipe 210 is formed longer than the outlet side circulation pipe 220 increases the likelihood that foreign matter is introduced into the circulation pipe, but can circulate the groundwater stably. Therefore, when the inlet side circulation pipe 210 is formed longer than the outlet side circulation pipe 220, the inlet side circulation pipe 210 is formed of the same material as the fire hose while the outlet side circulation pipe 220 ) May be formed of PE material or PVC material.

Of course, both the inlet side circulation pipe 210 and the outlet side circulation pipe 220 may be formed of a flexible and collapsible material such as a fire hose.

The manhole 400 may be accommodated in a predetermined internal space (S) at the upper end of the well (100) to be drilled, that is, the upper end of the well (100), as well as an operator in the inner space (S) of the manhole (400). It can be formed to have a width enough to enter and to perform a variety of tasks. A first through hole 401 is formed in the bottom surface of the manhole 400 so as to communicate with the well 100, and the groundwater pipes 3 and 4 are inserted into the main wall of the manhole 400. 2 through holes 402 are formed.

And the upper end of the manhole 400 is provided with a manhole cover 410 that can open and close the internal space (S). A sealing member 420 may be installed between the upper end of the manhole 400 and the manhole cover 410 corresponding thereto to prevent rainwater or foreign matter from entering. In addition, a sealing surface 403 may be formed between the manhole 400 and the manhole cover 410 so as to be stepped together to increase the sealing area to increase the sealing effect.

The underground heat exchanger of the geothermal heat pump system according to the present invention as described above has the following effects.

That is, the underground column heat exchanger of the standing column well type pumps groundwater from the well 100 by the submersible pump 300 together with the operation of the underground air conditioning system. Then, the groundwater (W) accumulated in the inside of the well 100 is introduced into the inlet side circulation pipe 210 and ascended by the submersible pump 300 installed in the inlet side circulation pipe 210 while being introduced. It flows into the groundwater pipe (3).

The groundwater flowing into the inlet side groundwater pipe (3) flows into the ground heat exchanger (2) through the inlet side groundwater pipe (3), and after heat exchanged with the refrigerant or the ground circulating water in the ground heat exchanger (2). It is introduced into the outlet side circulation pipe 220 through the discharge side ground water pipe 4 and recovered to the well 100 again. At this time, the refrigerant cooled or heated by the groundwater in the ground heat exchanger (2) is to be delivered to where necessary to cool or heat.

As described above, the groundwater W accumulated in the well 100 according to the operation of the submersible pump 300 has a pure thermal conductivity of kROCK = 3 w / mk of the rock layer 100 itself directly in contact with the groundwater. Since the thermal conductivity of the portion backfilled by the process is much higher than kGROUT = 0.4 to 0.8 w / mk, the heat conduction effect is excellent, and the synergy effect of the heat exchange rate and the heating and cooling efficiency are doubled. Here, a heat pump, a temperature sensor, etc. may be added as a separate component that achieves a cooling and heating effect by interworking with the heat exchanger 2, and these components are unnecessary parts of the scope of the present invention, and thus, the detailed description thereof. Is omitted.

On the other hand, when the underground heat exchanger is used for a certain period of time, when a piece of rock or other foreign matter is deposited at the bottom of the well and flows into the circulation pipe, the amount of groundwater circulated through the circulation pipe is reduced. However, since the heat exchange performance of the above ground heat exchanger may be reduced, it is necessary to periodically clean the circulation pipe.

In this case, in the related art, maintenance work becomes difficult because the circulation pipe must be pulled up after digging the periphery of the well again. However, in the present invention, the manhole cover (410) is installed inside the manhole 400, and the manhole cover 410 is installed at the open end of the manhole 400. When the 410 is separated, the well 100 may be immediately exposed, thereby facilitating maintenance work of the underground heat exchanger.

In addition, in the related art, as the circulation pipe is made of a rigid PVC material or a PE material that is more flexible than PVC but maintains a constant cross-sectional area, it is not only difficult to raise the circulation pipe of several hundred meters, but also a wide work. Space was also needed, and underground heat exchangers could not be installed in confined spaces, such as in the basement of buildings.

However, when the inlet side circulation pipe 210 or the outlet side circulation pipe 220 is formed of a flexible material that can be folded as in the present invention, as shown in FIGS. 5 and 6, in particular, the outlet side circulation pipe 220 ) Can be rolled up by a separate winding machine such as a reel 600, which facilitates the lifting of the circulation pipe as well as a storage space for storing the lifted circulation pipe. It is not necessary much to be able to install underground heat exchanger in limited space such as basement.

Looking at the details of the lifting operation to pull up the inlet side circulation pipe as follows.

First, the worker separates the manhole cover 410 from the manhole 400.

Subsequently, the couplings 511, 512, 521, and 522 of the intermediate connecting pipes 510 and 520 are released to fix the intermediate connecting pipes 510 and 520 to the fixed connecting pipes 111 and 112. And groundwater pipes (3) and (4). As a result, the fixed connection pipes 111 and 112 and the groundwater pipe 3 and 4 are separated from each other.

Subsequently, the cover plate 110 is separated from the case 101. At this time, since the inlet side circulation pipe 210 and the outlet side circulation pipe 220 are respectively coupled to the fixed connecting pipes 111 and 112 of the cover plate 110, the cover plate 110 has an appropriate height, that is, the The cover plate 110 is pulled up only to the extent that the couplings 215 and 225 of the circulation pipes 210 and 220 can be seen.

Subsequently, each of the circulation pipes 210 and 220 is released by releasing couplings 215 and 225 that couple the fixed connecting pipes 111 and 112 and the circulation pipes 210 and 220 of the cover plate 110. ) Is separated from the cover plate 110.

Subsequently, the circulation pipes 210 and 220, in particular, the outlet-side circulation pipe 220 are wound up to a reel 600, which is a winding machine, to carry out repair work.

Here, in order to use the reel, as shown in FIG. 6, the reel support 420 may protrude to a predetermined height so that the reel 600 is placed on the bottom surface of the manhole 400. In this case, it is preferable that the reel 600 is installed so that the height of the reel support 420 is about 2 m or more as the reel 600 is wound around the outlet side circulation pipe reaching several hundred meters. In addition, since the reel is large in size and the weight of the circulation pipe is gradually increased, it is difficult for the operator to directly turn it, so it is preferable to install a separate transmission device 700 to operate the reel 600 with the transmission device 700. can do. Of course, in the case of a small underground heat exchanger, the length of the recirculation tube may be relatively short, so that the height of the reel may be lower, and a worker may directly wind the coil without being connected to the power transmission device as described above.

7 shows an example in which the reel assembly is installed outside the manhole. In this case, the size of the reel 600 may be formed similarly to the above-described embodiment, and the transmission 700 for operating the reel 600 may also be installed similarly to the above-described embodiment. As a result, the effect is similar to that of the above-described embodiment, and thus a detailed description thereof will be omitted. However, in this case, as the reel is installed outside the manhole, a separate reel support part cannot be provided in the manhole, and a large work space is required, but the process of the worker entering the manhole reduces workability and safety. It can increase.

On the other hand, after the circulation pipe is cleaned, the underground heat exchanger is restored to its original state in the reverse order of lifting the circulation pipe. At this time, the circulation tube is inserted into the well and fixed, and then the manhole cover is covered with the manhole to finish.

In this way, when the ground heat exchanger is repaired, it is possible to eliminate the hassle of digging or burying the surroundings, thereby facilitating the maintenance work of the ground heat exchanger which should be periodically performed.

100: wells 110: open edition
111, 112: fixed connection pipe 210: inlet side circulation pipe
220: outflow side circulation pipe 221,222: waterproof layer
223: heat insulation layer 230, 240: weight
231,241: Through hole 250,260: Weight
300: submersible pump 400: manhole
510,520: Intermediate connector 215,225,511,512,521,522: Coupling

Claims

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is made of a foldable material that can overlap the inner circumferential surface when the groundwater is not filled,
The weight of the circulation pipe is provided with a weight of a material having a specific gravity greater than water, the weight of the underground heat pump of the geothermal heat pump is formed in the hole to communicate the inside and the outside of the circulation pipe.

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is formed of a waterproof material on the outer circumference and the inner circumferential surface of the outer circumference and the inner circumferential surface so that the inner circumferential surface may overlap when the groundwater is not filled.
The circulation pipe is composed of an inflow side circulation pipe through which groundwater flows from the well and an outlet side circulation pipe through which groundwater flows into the well.
The underground heat exchanger of the geothermal heat pump is installed so that the outlet side circulation pipe is closer to the bottom surface of the well than the inlet side circulation pipe.

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is made of one of a polyurethane built-in hose or rubber built-in hose so that the inner circumferential surface may overlap when the ground water is not filled,
The circulation pipe is composed of an inflow side circulation pipe through which groundwater flows from the well and an outlet side circulation pipe through which groundwater flows into the well.
The underground heat exchanger of the geothermal heat pump is installed so that the outlet side circulation pipe is closer to the bottom surface of the well than the inlet side circulation pipe.

delete

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is made of a foldable material that can overlap the inner circumferential surface when the groundwater is not filled,
A manhole is provided on the upper side of the well, and a groundwater pipe connected to the ground heat exchanger is penetrated through the mandrel of the manhole, and an upper plate of the well is provided with a cover plate covering the well. The cover plate is installed through the fixed connection pipe detachably connected to the circulation pipe, the underground heat exchanger of the geothermal heat pump is detachably connected between the ground water pipe and the fixed connection pipe.

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is made of a foldable material that can overlap the inner circumferential surface when the groundwater is not filled,
The circulation pipe is composed of an inflow side circulation pipe through which groundwater flows from the well and an outlet side circulation pipe through which groundwater flows into the well.
The outlet side circulation pipe is installed closer to the bottom surface of the well than the inlet side circulation pipe,
Underground heat exchanger of the geothermal heat pump is further provided with a reel (reel) to the upper end of the circulation pipe can be wound around the circulation pipe (reel).

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is made of a foldable material that can overlap the inner circumferential surface when the groundwater is not filled,
The circulation pipe is composed of an inflow side circulation pipe through which groundwater flows from the well and an outlet side circulation pipe through which groundwater flows into the well.
The underground heat exchanger of the geothermal heat pump is installed so that the outlet side circulation pipe is closer to the bottom surface of the well than the inlet side circulation pipe.

And a circulation pipe inserted in the longitudinal direction of the well drilled to collect underground water in the underground rock layer so that groundwater accumulated in the well is circulated between the well and the ground heat exchanger.
The circulation pipe is made of a foldable material that can overlap the inner circumferential surface when the groundwater is not filled,
The circulation pipe is provided with a weight of a material having a specific gravity greater than that of water, and the weight is formed with a hole communicating the inside and the outside of the circulation pipe,
Underground heat exchanger of the geothermal heat pump is further provided with a reel (reel) to the upper end of the circulation pipe can be wound around the circulation pipe (reel).