JP6839913B2 - Geothermal utilization system - Google Patents

Description

The present invention relates to a geothermal heat utilization system and a geothermal heat exchanger.

Underground temperature is maintained almost constant throughout the year due to the heat insulating effect of the ground. Taking advantage of this, a geothermal heat utilization system has been proposed in which heating and cooling are performed using geothermal heat.

Such a geothermal heat utilization system is configured to circulate a heat medium such as a circulating fluid to exchange heat with the surrounding ground. In the geothermal heat utilization system, the geothermal heat can be used for cooling when the temperature is higher than the underground temperature, and the geothermal heat can be used for heating when the temperature is lower than the underground temperature.

Patent Document 1 describes a geothermal heat utilization system including a steel pipe filled with a refrigerant liquid and buried in the ground, and a circulation pipe arranged inside and outside the steel pipe. In this geothermal heat utilization system, heat is exchanged between the refrigerant liquid in the steel pipe and the surrounding ground via the steel pipe by circulating the circulating liquid through the circulation pipe.

Patent Document 2 describes a geothermal heat utilization system that exchanges heat using a heat pipe arranged in a drilling hole excavated to a depth of 100 to 150 m. In this geothermal heat utilization system, after installing a heat pipe in the excavation hole, the excavation hole is filled with a filler such as silica sand.

Japanese Unexamined Patent Publication No. 2006-10098 Japanese Unexamined Patent Publication No. 2009-257737

In the technique of Patent Document 1, heat exchange between the circulating liquid in the circulating pipe and the ground is performed through the refrigerant liquid filled around the circulating pipe and the steel pipe. Here, since the refrigerant liquid has high heat storage property and is inferior in heat dissipation property, it is considered that the speed of heat exchange between the circulating liquid and the ground is not sufficient in the technique of Patent Document 1.

On the other hand, the technique of Patent Document 2 is, so to speak, a technique of directly burying a heat pipe in the ground, so that heat exchange inside and outside the heat pipe is caused by variations in the properties of the soil in the ground. It is greatly affected by temperature unevenness inside. That is, the heat exchange capacity of each individual geothermal heat utilization system varies and becomes unstable due to the influence of the installed ground.
Further, in the technique of Patent Document 2, since it is necessary to form a very deep excavation hole as described above, the construction work and the structure of the system become large-scale, so that it cannot be used for heating and cooling of a general household, for example. difficult.

The present invention has been made in view of the above problems, and can realize a good heat exchange rate between a heat medium such as a circulating fluid and the surrounding ground, and heat for each individual underground heat utilization system. We provide underground heat utilization systems and underground heat exchangers that can stabilize the exchange capacity and secure a sufficient amount of heat that can be exchanged per unit time even with relatively small-scale equipment. Is what you do.

According to the present invention, a part of a circulation path for circulating a heat medium is provided inside and an underground heat exchanger buried in the ground is provided, and the underground heat exchanger is provided through the underground heat exchanger. An underground heat utilization system that collects heat from the surrounding ground of a heat exchanger or dissipates heat to the surrounding ground. The underground heat exchanger is a container that is resistant to corrosion against the soil of the surrounding ground and the container. It has a metal heat storage material sealed and filled inside, and the circulation path is a circulation pipe that circulates the heat medium inside, and a part of the circulation pipe passes through the inside of the container. The area around the circulation pipe is filled with the metal heat storage material inside the container, and the container is made of a material having a higher thermal conductivity than the metal heat storage material, and the underground heat utilization system. Is provided with a water-type air conditioner that circulates circulating water in a pipe installed on the ceiling or under the floor of the temperature control target room, and the water-type air conditioner heats by bringing the heat medium and the circulating water into thermal contact. It has a heat exchange unit for exchanging and a heat medium circulation pump unit for circulating the heat medium in the circulation path, and the circulation path is said to be between the heat exchange unit and the underground heat exchanger. The underground heat utilization system for circulating a heat medium includes a plurality of the underground heat exchangers and is a switching means for switching the underground heat exchangers that exchange heat with the heat exchange unit. A geothermal heat utilization system is provided, which is characterized by further providing.

According to the present invention, it is possible to realize a good heat exchange rate between a heat medium such as a circulating fluid and the surrounding ground, and to stabilize the heat exchange capacity of each individual geothermal heat utilization system. Moreover, it is possible to secure a sufficient amount of heat that can exchange heat per unit time even with a relatively small-scale facility.

It is a schematic diagram which shows the structure of the geothermal heat utilization system which concerns on 1st Embodiment. It is a perspective view which shows the underground heat exchanger of the underground heat utilization system which concerns on 1st Embodiment. It is a schematic diagram which shows the structure of the geothermal heat utilization system which concerns on 2nd Embodiment. It is a perspective view for demonstrating the geothermal heat exchanger of the geothermal heat utilization system which concerns on 2nd Embodiment, of which (a) shows the concrete foundation which formed the recess, and (b) is to the recess. It shows the state where the geothermal heat exchanger is constructed by filling the metal heat storage material. It is a schematic diagram which shows the structure of the geothermal heat utilization system which concerns on 3rd Embodiment. It is a schematic diagram which shows the structure of the geothermal heat utilization system which concerns on 4th Embodiment. It is a schematic diagram which shows the structure of the geothermal heat utilization system which concerns on 5th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same components are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

[First Embodiment]
FIG. 1 is a schematic view showing the configuration of the geothermal heat utilization system according to the first embodiment.
FIG. 2 is a perspective view showing the geothermal heat exchanger 10 of the geothermal heat utilization system according to the first embodiment.

In the geothermal heat utilization system according to the present embodiment, a part of the circulation path 20 for circulating the heat medium M (for example, a part 21a of the first circulation pipe 21) is arranged inside and is buried in the ground. A medium heat exchanger 10 is provided, and heat is collected from the surrounding ground G of the underground heat exchanger 10 or radiated from the surrounding ground G via the geothermal heat exchanger 10. The geothermal heat exchanger 10 has a container 14 that is resistant to corrosion against the soil of the surrounding ground G, and a metal heat storage material 12 that is hermetically filled in the container 14.

Further, in the geothermal heat exchanger 10 according to the present embodiment, a part 21a of a pipe (first circulation pipe 21) having both ends communicating with each other is disposed inside and is buried in the ground. The geothermal heat exchanger 10 used is used to collect heat from the surrounding ground G or dissipate heat to the surrounding ground G. The geothermal heat exchanger 10 has a container 14 that is resistant to corrosion against the soil of the surrounding ground G, and a metal heat storage material 12 that is hermetically filled in the container 14.

In the present embodiment, as shown in FIG. 1, a case where the geothermal heat utilization system is used for temperature control (cooling / heating) of the temperature control target room 62 in the building 60 such as a detached house will be described. In this case, the geothermal heat exchanger 10 can be buried in the ground under a parking lot or a garden, for example. FIG. 1 shows an example in which the geothermal heat exchanger 10 is arranged under the garden.

The circulation path 20 is composed of, for example, a first circulation pipe 21 and a second circulation pipe 25.
Both ends of the first circulation pipe 21 communicate with each other, and a part 21a of the first circulation pipe 21 is arranged inside the geothermal heat exchanger 10 (that is, inside the container 14).
Both ends of the second circulation pipe 25 communicate with each other, and a part 25a of the second circulation pipe 25 is arranged inside the heat pump unit 30, which will be described later.
Both ends of the first circulation pipe 21 and the second circulation pipe 25 are connected to each other. As a result, the first circulation pipe 21 and the second circulation pipe 25 communicate with each other, and the circulation path 20 is formed by the first circulation pipe 21 and the second circulation pipe 25.

The heat medium M circulating in the first circulation pipe 21 exchanges heat with the surrounding ground G via the metal heat storage material 12 and the container 14.
Here, since the metal heat storage material 12 has better heat dissipation than the liquid, it realizes a good heat exchange rate between the heat medium M circulating in the first circulation pipe 21 and the surrounding ground G. be able to. Therefore, even in a relatively small-scale geothermal heat utilization system (particularly, a relatively small geothermal heat exchanger 10), it is possible to secure a sufficient amount of heat exchangeable per unit time. Become. Therefore, the geothermal heat utilization system can be suitably used for heating and cooling applications in general households.
The heat medium M may be a liquid or a gas. Specific examples of the heat medium M include hydrofluorocarbons (HFCs) and water.

The temperature in the ground is almost constant if the depth is about 10 m or more and 15 m or less underground. Therefore, the depth at which the geothermal heat exchanger 10 is installed is set so that the lower surface of the geothermal heat exchanger 10 is located at a place where the depth of the surrounding ground G from the ground surface is shallower than 20 m. It is enough.
It is preferable to bury the geothermal heat exchanger 10 in the ground so that the upper surface of the geothermal heat exchanger 10 is located at a depth of 10 m or more from the ground surface of the surrounding ground G.

The metal heat storage material 12 filled in the container 14 preferably contains non-ferrous slag such as copper slag or ferronickel slag.
Copper slag is a by-product generated in the process of refining copper, and is a glassy particle having a high iron oxide content. Since copper slag contains organic solvents, if copper slag is buried in the ground as it is, harmful substances may seep into the soil. The same applies to non-ferrous slag other than copper slag.
In the present embodiment, since the metal heat storage material 12 is hermetically filled in the corrosion-resistant container 14, the metal heat storage material 12 is suitably protected from the surrounding ground G. Therefore, it is possible to suppress the exudation of harmful substances from the metal heat storage material 12 made of copper slag or the like into the soil.
The metal heat storage material 12 may contain only non-ferrous slag such as copper slag, or may be filled with a liquid such as water or oil between the non-ferrous slag. The weight of the liquid to be filled is preferably less than the weight of the non-ferrous slag.
Alternatively, the metal heat storage material 12 may be a mixture of non-ferrous slag such as copper slag and concrete, that is, non-ferrous slag concrete such as copper slag concrete. The non-ferrous slag concrete may not contain aggregate. In this case, the non-ferrous slag concrete is composed of non-ferrous slag and cement that binds the non-ferrous slag to each other.
By using a metal heat storage material 12 in which the gaps between the non-ferrous slags are filled with liquid or non-ferrous slag concrete, the thermal conductivity of the metal heat storage material 12 can be improved as compared with the case where the gaps between the non-ferrous slags are voids. Can be good.

The metal heat storage material 12 may contain not only non-ferrous slag such as copper slag but also a metal material other than non-ferrous slag (such as crushed metal fragments). Alternatively, the metal heat storage material 12 does not contain non-ferrous slag and may be made of a metal material other than non-ferrous slag.
Even if the metal heat storage material 12 is other than non-ferrous slag, if the metal heat storage material 12 is buried in the ground as it is, there is a possibility that harmful substances may be generated due to the reaction between the metal heat storage material 12 and the moisture in the soil. However, in the present embodiment, since the metal heat storage material 12 is hermetically filled in the corrosion-resistant container 14, it is possible to prevent harmful substances from seeping into the soil in this case as well.

The container 14 is preferably made of a material having a higher thermal conductivity than the metal heat storage material 12. As a result, the heat exchange rate between the heat medium M circulating in the first circulation pipe 21 and the surrounding ground G can be further improved.
However, the thermal conductivity of the container 14 may be the same as the thermal conductivity of the metal heat storage material 12, or may be less than the thermal conductivity of the metal heat storage material 12.
Here, the thermal conductivity of the metal heat storage material 12 means the thermal conductivity of the region filled with the metal heat storage material 12. Therefore, when the metal heat storage material 12 is composed of particulate non-ferrous slag, the thermal conductivity of the metal heat storage material 12 is the thermal conductivity of the portion including the non-ferrous slag particles and the air layer between the particles. means.

The container 14 is made of, for example, an iron-based material that has been subjected to corrosion resistance treatment such as chromium, stainless steel, and chrome plating, or a resin material that contains a carbon fiber material.
As a result, the container 14 can be made corrosion resistant to the surrounding ground G.
Further, for example, when the metal heat storage material 12 is non-iron slag such as copper slag or non-iron slag concrete such as copper slag concrete, the container 14 is subjected to corrosion resistance treatment of a metal material (for example, chrome, stainless steel, chrome plating or the like). The thermal conductivity of the container 14 can be made higher than the thermal conductivity of the metal heat storage material 12 by forming the container 14 with an iron-based material or the like.

It is preferable that the outer surface of the container 14 is formed with irregularities. By doing so, the contact area between the container 14 and the surrounding ground G can be increased as compared with the case where the outer surface of the container 14 is flat. Therefore, the heat exchange efficiency between the underground heat exchanger 10 and the surrounding ground G can be improved. That is, the efficiency of heat collection from the surrounding ground G of the geothermal heat exchanger 10 and the efficiency of heat dissipation from the geothermal heat exchanger 10 to the surrounding ground G can be improved.

The container 14 has, for example, a side peripheral wall portion 15, a top plate portion 16, and a bottom plate portion 17.
It is preferable that the upper surface (upper surface of the top plate portion 16) and the lower surface (lower surface of the bottom plate portion 17) of the container 14 are arranged in parallel with each other. Further, the upper surface and the lower surface of the container 14 are arranged horizontally, for example. Further, the geothermal heat exchanger 10 is arranged so that the side peripheral wall portion 15 is in an upright state.

The side peripheral wall portion 15 is formed in a tubular shape with both the lower end and the upper end open.
The top plate portion 16 is formed in a flat plate shape and closes the opening at the upper end of the side peripheral wall portion 15.
The bottom plate portion 17 is formed in a flat plate shape and closes the opening at the lower end of the side peripheral wall portion 15.
The peripheral edge of the top plate 16 is joined to the edge of the opening at the upper end of the side peripheral wall 15 over the entire circumference by welding or the like. As a result, the upper end of the container 14 is sealed.
Similarly, the peripheral edge portion of the bottom plate portion 17 is joined to the edge of the opening at the lower end of the side peripheral wall portion 15 over the entire circumference by welding or the like. As a result, the lower end of the container 14 is sealed.
More specifically, for example, the container 14 is formed in a rectangular parallelepiped shape. That is, the side peripheral wall portion 15 is formed in a tubular shape having a rectangular cross-sectional shape.

Each of the side peripheral wall portion 15, the top plate portion 16, and the bottom plate portion 17 is made of a material that is resistant to corrosion against the soil of the surrounding ground G.
Further, preferably, each of the side peripheral wall portion 15, the top plate portion 16, and the bottom plate portion 17 is made of a material having a higher thermal conductivity than the metal heat storage material 12.

On the outer surface of the side peripheral wall portion 15 of the container 14, for example, irregularities having a wavy flat cross-sectional shape are formed.
As a result, the contact area between the outer surface of the side peripheral wall portion 15 and the surrounding ground G can be increased as compared with the case where the outer surface of the side peripheral wall portion 15 is flat. The heat exchange efficiency with the surrounding ground G can be improved.
Further, the load bearing performance of the side peripheral wall portion 15 can be improved as compared with the case where the outer surface of the side peripheral wall portion 15 is flat. Therefore, the side peripheral wall portion 15 can be made thinner. Alternatively, the geothermal heat exchanger 10 can be buried under a heavy object such as a building.
The side peripheral wall portion 15 of the container 14 is formed, for example, in the shape of a plate having a corrugated flat cross-sectional shape. That is, corrugated irregularities are also formed on the inner surface of the side peripheral wall portion 15 of the container 14. As a result, the contact area between the inner surface of the side peripheral wall portion 15 and the metal heat storage material 12 can be increased as compared with the case where the inner surface of the side peripheral wall portion 15 is flat, so that the container 14 and the metal heat storage material can be increased. The heat exchange efficiency with 12 can be improved.
However, the inner surface of the side peripheral wall portion 15 may be formed in a flat shape.

Further, the outer surfaces of the top plate portion 16 and the bottom plate portion 17 of the container 14 may also have corrugated irregularities. As a result, the contact area between the outer surfaces of the top plate 16 and the bottom plate 17 and the surrounding ground G can be increased as compared with the case where the outer surfaces of the top plate 16 and the bottom plate 17 are flat. The heat exchange efficiency between them can be improved.
Similarly, corrugated irregularities may be formed on the outer surfaces of the top plate portion 16 and the bottom plate portion 17 of the container 14. As a result, the contact area between the top plate portion 16 and the bottom plate portion 17 and the metal heat storage material 12 can be increased as compared with the case where the inner surfaces of the top plate portion 16 and the bottom plate portion 17 are flat. The heat exchange efficiency between them can be improved.

Here, an example of a specific structure of the container 14 will be described with reference to FIG.
The side peripheral wall portion 15 of the container 14 has a plurality of plate-shaped members (eight plate-shaped members 171, 172, 173, 174, 175, 176, 177, 178 in the illustrated example) formed in a corrugated manner, respectively. It is configured to include a plurality of columnar members (in the illustrated example, eight columnar members 111, 112, 113, 114, 115, 116, 117 and 118).
The plate-shaped members 171 to 178 and the columnar members 111 to 118 are preferably made of a weldable material such as metal.
The plate-shaped members 171 to 178 stand vertically, and the columnar members 111 to 118 also stand vertically.
Each plate-shaped member 171 to 178 is formed in a rectangular shape in a side view. The shape of the columnar members 111 to 118 may be columnar or prismatic.
Among the plate-shaped members 171 to 178, the plate-shaped members adjacent to each other are connected to each other via columnar members 111 to 118.
More specifically, the plate-shaped members 171 to 178 are arranged in the order of the plate-shaped members 171 to 178 in a counterclockwise direction in a plan view, and a tubular body having a rectangular flat cross-sectional shape is formed as a columnar member 111-118. It is composed with.

For example, the plate-shaped members 171 and 172 are located on the same plane as each other, are arranged adjacent to each other in the horizontal direction, and are connected to each other via a columnar member 115 located between them. The plate-shaped members 173 and 174 are located on the same plane as each other, are arranged adjacent to each other in the horizontal direction, and are connected to each other via a columnar member 116 located between them. The plate-shaped members 175 and 176 are located on the same plane as each other, are arranged adjacent to each other in the horizontal direction, and are connected to each other via a columnar member 117 located between them. The plate-shaped members 177 and 178 are located on the same plane as each other, are arranged adjacent to each other in the horizontal direction, and are connected to each other via a columnar member 118 located between them.

The plate-shaped members 171 and 172 and the plate-shaped members 173 and 174 are arranged orthogonal to each other. The plate-shaped members 173 and 174 and the plate-shaped members 175 and 176 are arranged orthogonal to each other. The plate-shaped members 175 and 176 and the plate-shaped members 177 and 178 are arranged orthogonal to each other. The plate-shaped members 177 and 178 and the plate-shaped members 171 and 172 are arranged orthogonal to each other. Further, the plate-shaped members 171 and 172 and the plate-shaped members 176 and 175 face each other in parallel. Similarly, the plate-shaped members 173 and 174 and the plate-shaped members 178 and 177 face each other in parallel.

The plate-shaped member 171 and the plate-shaped member 178 are connected to each other via a columnar member 111. Similarly, the plate-shaped member 172 and the plate-shaped member 173 are connected to each other via a columnar member 112. Similarly, the columnar member 174 and the columnar member 175 are connected to each other via the columnar member 113. Similarly, the columnar member 176 and the columnar member 177 are connected to each other via the columnar member 114.

Two slits are formed on the side peripheral surfaces of the columnar members 111 to 118 along the longitudinal direction of the columnar members 111 to 118. Each slit is provided at a position corresponding to the plate-shaped members 171 to 178 to which the columnar members 111 to 118 are connected.
The edge portions of both ends of each plate-shaped member 171 to 178 in the horizontal direction are inserted into the corresponding slits of the corresponding columnar members 111 to 118 over the longitudinal direction, and the corresponding columnar members 111 to 118 are inserted into the corresponding slits. On the other hand, they are joined by welding or the like (see the partially enlarged view in FIG. 2).

Further, the top plate portion 16 and the bottom plate portion 17 are each formed in a flat plate shape. The top plate portion 16 and the bottom plate portion 17 are preferably made of stainless steel.
Then, as described above, the peripheral edge portion of the top plate portion 16 is joined to the edge of the opening at the upper end of the side peripheral wall portion 15 over the entire circumference by welding or the like, and similarly, the peripheral edge portion of the bottom plate portion 17 is joined. , The edge of the opening at the lower end of the side peripheral wall portion 15 is joined over the entire circumference by welding or the like.

As shown in FIG. 1, for example, each of both ends of the first circulation pipe 21 protrudes from the container 14. Then, as shown in FIG. 1, flange portions 22 are formed at the tips of both end portions of the first circulation pipe 21. As a result, the first circulation pipe 21 in which a part 21a is introduced into the underground heat exchanger 10 can be easily connected to another pipe (specifically, for example, the second circulation pipe 25).
In FIG. 2, the flange portion 22 is not shown.
One end of the first circulation pipe 21 is an inlet portion 21b for introducing the heat medium M into the first circulation pipe 21, and the other end of the first circulation pipe 21 is heat from the first circulation pipe 21. The outlet portion 21c for deriving the medium M.

For example, the inlet portion 21b and the outlet portion 21c of the first circulation pipe 21 project from the top plate portion 16 of the container 14. However, the inlet portion 21b and the outlet portion 21c of the first circulation pipe 21 may protrude from the side peripheral wall portion 15 of the container 14 or may protrude from the bottom plate portion 17 of the container 14.

As an example, the container 14 preferably has a shape in which the width dimension and the depth dimension are larger than the vertical dimension thereof. By doing so, since the container 14 has a flat shape, a sufficient contact area between the container 14 and the surrounding ground G can be secured, so that the heat between the underground heat exchanger 10 and the surrounding ground G can be secured. The exchange efficiency can be improved. Further, since the entire geothermal heat exchanger 10 can be easily installed at the same position as the deepest part of the geothermal heat exchanger 10, the geothermal heat is different from the case where the pipe is vertically buried in the ground. It is not necessary to increase the installation depth (depth at the deepest position) of the exchanger 10 so much.

The geothermal heat utilization system includes a water-type air conditioner that circulates circulating water W through pipes (ceiling radiation pipe 51, underfloor radiation pipe 53) installed in the ceiling 64 or underfloor 66 of the temperature control target room 62.
The water-type air conditioner has a heat exchange unit (heat pump unit 30) that exchanges heat between the heat medium M and the circulating water W by bringing the heat medium M and the circulating water W into thermal contact, and the heat medium M. It has a heat medium circulation pump unit 23 that circulates the heat medium M in the circulation path 20 by pumping.

The heat pump unit 30 is installed on the ground outside (that is, outdoors) of the building 60, for example. However, the heat pump unit 30 may be installed inside the building 60 (indoors) or may be buried in the ground.

In the second circulation pipe 25, a part 25a of the second circulation pipe 25 is arranged inside the heat pump unit 30, and both ends are connected to the first circulation pipe 21. The second circulation pipe 25 and the first circulation pipe 21 form a circulation path 20 for circulating the heat medium M in a loop between the heat pump unit 30 and the geothermal heat exchanger 10.

Here, flange portions 24 are formed at both ends of the second circulation pipe 25, respectively.
Then, the flange portion 22 of the inlet portion 21b of the first circulation pipe 21 is fixed to the flange portion 24 at one end of the second circulation pipe 25, so that the inlet portion 21b of the first circulation pipe 21 and the second circulation pipe are fixed. One end of 25 is connected to each other in a state of communicating with each other.
Similarly, the flange portion 22 of the outlet portion 21c of the first circulation pipe 21 is fixed to the flange portion 24 at the other end of the second circulation pipe 25, so that the outlet portion 21c and the second outlet portion 21c of the first circulation pipe 21 are fixed. The other end of the circulation pipe 25 is connected to each other in a state of communicating with each other.
Although FIG. 1 shows an example in which the flange portion 24 and the flange portion 22 are arranged on the ground, the flange portion 24 and the flange portion 22 may be buried in the ground.

Here, the building 60 is constructed on a concrete foundation (foundation structure) 70 such as a solid foundation installed on the ground, for example, as shown in FIG.

The building 60 is provided with, for example, a cooling circulating water channel that circulates the circulating water W for cooling and a heating circulating water channel that circulates the circulating water W for heating.

Of these, the cooling circulation channel is, for example, a loop-shaped cooling circulation channel that communicates with the ceiling radiating pipe 51 installed on the ceiling 64 of the temperature control target room 62 and the ceiling radiating pipe 51 together with the ceiling radiating pipe 51. It is provided with a pipe 45 forming the above. That is, one end of the ceiling radiating pipe 51 communicates with one end of the pipe 45, and the other end of the ceiling radiating pipe 51 communicates with the other end of the pipe 45.
The pipe 45 connects the ceiling radiating pipe 51 and the heat pump unit 30 to each other, and a part of the pipe 45 is arranged in the heat pump unit 30.
Further, the pipe 45 is provided with a pump 49 for circulating the circulating water W in the cooling circulating water channel and an on-off valve 41.
When the on-off valve 41 is in the open state, the pump 49 pumps the circulating water W in the cooling circulating water channel, so that the circulating water W circulates in the cooling circulating water channel. On the other hand, when the on-off valve 41 is in the closed state, the circulating flow of the circulating water W in the cooling circulating water channel is regulated. That is, the on-off valve 41 has a state of allowing the circulating flow of the circulating water W in the cooling circulating water channel (open state) and a state of restricting the circulating flow of the circulating water W (closed state). It is possible to switch to.
The operation of switching the on-off valve 41 from the open state to the closed state is preferably performed with the pump 49 stopped in advance. Further, it is preferable that the pump 49 is started in a state in which the on-off valve 41 is switched from the closed state to the open state in advance.
Further, below the ceiling radiating pipe 51, a water droplet receiver 55 for receiving water droplets dripping after dew condensation on the ceiling radiating pipe 51 is provided.

On the other hand, the heating circulation water channel is, for example, a loop-shaped heating circulation water channel that communicates with the underfloor radiant pipe 53 installed under the floor 66 of the temperature control target room 62 and the underfloor radiant pipe 53 together with the underfloor radiant pipe 53. The pipe 47 and the pipe 47 forming the above are provided. That is, one end of the underfloor radiating pipe 53 communicates with one end of the pipe 47, and the other end of the underfloor radiating pipe 53 communicates with the other end of the pipe 47.
The pipe 47 connects the underfloor radiant pipe 53 and the heat pump unit 30 to each other, and a part of the pipe 47 is arranged in the heat pump unit 30.
Further, the pipe 47 is provided with a pump 48 for circulating the circulating water W in the heating circulation channel and an on-off valve 43.
When the on-off valve 43 is in the open state, the pump 48 pumps the circulating water W in the heating circulating water channel, so that the circulating water W circulates in the heating circulating water channel. On the other hand, when the on-off valve 43 is in the closed state, the circulating flow of the circulating water W in the heating circulating water channel is regulated. That is, the on-off valve 43 has a state of allowing the circulating flow of the circulating water W in the heating circulating water channel (open state) and a state of restricting the circulating flow of the circulating water W (closed state). It is possible to switch to.
The operation of switching the on-off valve 43 from the open state to the closed state is preferably performed with the pump 48 stopped in advance. Further, it is preferable that the pump 48 is started in a state in which the on-off valve 43 is switched from the closed state to the open state in advance.

Although not shown, the heat pump unit 30 includes an evaporator, a condenser, a compressor, an expansion valve, a four-way valve, a pipe connecting them, and the like, and the inside is filled with a refrigerant. By switching with a four-way valve, the cooling operation using the cooling circulation water channel and the heating operation using the heating circulation water channel can be switched. The roles of the evaporator and the condenser are reversed between the cooling operation and the heating operation.

When the temperature of the surrounding ground G is lower than the temperature of the temperature control target chamber 62, such as in summer, during the cooling operation, the cooling circulation channel is selected from the cooling circulation channel and the heating circulation channel. Selectively operate. That is, while the pump 48 of the heating circulation channel is stopped and the on-off valve 43 is closed, the on-off valve 41 of the cooling circulation channel is opened and the pump 49 is operated.
At this time, (1) the refrigerant in the evaporator evaporates by the thermal energy (in this case, positive thermal energy (heat)) received from the circulating water W in the piping 45 of the cooling circulation water channel, and (2) evaporates. The refrigerant is compressed by the compressor and transferred to the condenser, and (3) the geothermal energy received by the refrigerant in the condenser from the heat medium M in the second circulation pipe 25 of the circulation path 20 (in this case, minus). The cooling cycle is carried out in the order of condensing and becoming a liquid again by being cooled by the thermal energy (cooling heat) of (4) and returning the refrigerant to the evaporator via the expansion valve.
As a result, the circulating water W in the piping 45 of the cooling circulating water channel is cooled by passing through the heat pump unit 30. The cooled circulating water W is transferred from the pipe 45 to the ceiling radiating pipe 51. Therefore, the temperature control target chamber 62 is cooled by radiative cooling from the ceiling radiation pipe 51.
At this time, the circulating water W in the ceiling radiating pipe 51 is heated by the positive thermal energy received from the atmosphere in the temperature control target chamber 62, and is transferred to the pipe 45 again.
On the other hand, the geothermal heat exchanger 10 consumes the geothermal heat energy (cold heat) stored in advance by supplying cold heat to the heat pump unit 30, and the temperature gradually rises. While sufficient cold heat is supplied from the geothermal heat exchanger 10 through the circulation path 20, the heat pump unit 30, and the cooling water channel in this order, that is, the temperature of the geothermal heat exchanger 10 is the temperature control target room. While the temperature is sufficiently low compared to the room temperature of 62, the cooling cycle described above functions, and the temperature control target chamber 62 can be cooled.
While the operation of the geothermal heat utilization system is stopped, the geothermal heat exchanger 10 gradually stores the geothermal heat energy (in this case, cold heat) received from the surrounding ground G again. That is, the underground heat exchanger 10 is gradually cooled until it becomes substantially isothermal to the temperature of the surrounding ground G.

On the other hand, when the temperature of the surrounding ground G is higher than the temperature of the temperature control target room 62, such as in winter, during the heating operation, the heating circulation of the cooling circulation channel and the heating circulation channel Selectively operate the waterway. That is, while the pump 49 of the cooling circulation channel is stopped and the on-off valve 41 is closed, the on-off valve 43 of the heating circulation channel is opened and the pump 48 is operated.
At this time, (1) the refrigerant in the evaporator evaporates due to the geothermal heat energy (in this case, positive heat energy (heat)) received from the heat medium M in the second circulation pipe 25 of the circulation path 20. 2) The evaporated refrigerant is compressed by the compressor and transferred to the condenser, and (3) the refrigerant in the condenser receives the thermal energy received from the circulating water W in the pipe 47 of the circulation water channel for heating (in this case, minus). By being cooled by the thermal energy (cold heat) of the above, it condenses into a liquid again, and (4) the refrigerant returns to the evaporator via the expansion valve, and the heating cycle is performed in this order.
As a result, the circulating water W in the piping 47 of the heating circulating water channel is heated by passing through the heat pump unit 30. The heated circulating water W is transferred from the pipe 47 to the underfloor radiating pipe 53. Therefore, the temperature control target room 62 is heated by the radiant heat from the underfloor radiant pipe 53 (so-called floor heating can be performed).
At this time, the circulating water W in the underfloor radiant pipe 53 is cooled by the negative thermal energy received from the atmosphere in the temperature control target chamber 62 via the floor surface or the like, and is transferred to the pipe 47 again.
On the other hand, the geothermal heat exchanger 10 consumes the geothermal energy (heat) stored in advance by supplying heat to the heat pump unit 30, and the temperature gradually decreases. While sufficient heat is supplied from the geothermal heat exchanger 10 through the circulation path 20, the heat pump unit 30, and the heating circulation water channel in this order, the above-mentioned heating cycle functions to move the temperature control target room 62. Can be heated.
While the operation of the geothermal heat utilization system is stopped, the geothermal heat exchanger 10 gradually stores the geothermal energy (in this case, heat) received from the surrounding ground G again. That is, the underground heat exchanger 10 is gradually heated until it becomes substantially isothermal to the temperature of the surrounding ground G.

In this way, the heat pump unit 30 exchanges heat by bringing the heat medium M and the circulating water W into thermal contact with each other, and cools or heats the circulating water W, and eventually cools or heats the temperature control target chamber 62. ..

Hereinafter, an example of a model relating to the required amount of the metal heat storage material 12 for securing the desired heating / cooling capacity and achieving the desired COP (Coefficient Of Performance) during the desired operating time will be described.

The capacity required for heating and cooling a living room is generally said to be 150 W / h per ^{1 m 2.} Therefore, if the living room is 100 m ² , the capacity of 15,000 W / h (15 kW / h) ^{is required, and if the living room is 200 m 2} , the capacity of 30,000 W / h (30 kW / h) is required.
Here, it is assumed that a capacity of 30 kW / h is consumed for heating and cooling.

First, a case where the geothermal heat utilization system is used for cooling will be described.

In order to secure a cooling capacity of 30 kW / h and achieve, for example, COP 4.0, the amount of heat exhausted from the heat pump unit 30 to the geothermal heat exchanger 10 per hour is 42 kW. Therefore, in order to secure, for example, 7 hours as the duration of cooling, it is sufficient that a total of 294 kW of heat can be exhausted from the heat pump unit 30 to the geothermal heat exchanger 10.

^{The required amount (Xm 3} ) of the metal heat storage material 12 for allowing this amount of heat to be exhausted to the geothermal heat exchanger 10 is calculated as follows.
It is assumed that the container 14 of the geothermal heat exchanger 10 is filled with copper slag having ^{a specific gravity of 3600 kg / m 3 as the metal heat storage material 12.} The specific heat of the copper slag is, for example, about 0.208 kcal / kg · ° C., but here, it is assumed that the specific heat of the copper slag is underestimated to be 0.2 kcal / kg · ° C.
Further, it is assumed that the room temperature of the temperature control target chamber 62 without cooling is 30 ° C. and the temperature of the surrounding ground G is 15 ° C.
Further, the utilization efficiency of the heat energy (cold heat energy) stored in the geothermal heat exchanger 10 is 100%, and the exhaust heat from the heat pump unit 30 to the geothermal heat exchanger 10 causes the heat in the geothermal heat exchanger 10 to be exhausted. It is assumed that the heat energy is used for cooling without loss until the temperature of the metal heat storage material 12 (copper slag) rises from 15 ° C. to 30 ° C.
Then, it is the amount of heat exhausted from the heat pump unit 30 to the geothermal heat exchanger 10 from the start of operation of the geothermal heat utilization system to the end of consuming the heat energy stored in the geothermal heat exchanger 10. 294 (kW) = 3600 · X (kg) x 0.2 (kcal / kg · ° C) x ((30 (° C) -15 (° C)) = 10800 · X (kcal) = 10800 · X / 860 (kW) ) = Approximately 12.5 · X (kw).
Therefore, the required amount of the metal heat storage material 12 X (m ³ ) = about 294 / 12.5 = about 24 (m ³ ).
For example, when cooling is performed using a geothermal heat utilization system for 7 hours during the daytime in summer, the heat of the geothermal heat exchanger 10 is transferred to the surrounding ground G using the remaining 17 hours of the day. All you have to do is dissipate heat.

Actually, even while the geothermal heat utilization system is in operation, heat is exhausted from the geothermal heat exchanger 10 to the surrounding ground G in parallel. Therefore, even by using a metal heat storage material 12 in an amount smaller than the amount obtained in the calculation here, a cooling capacity of 30 kW / h can be secured for 7 hours and COP 4.0 can be achieved. Can be expected.

Next, a case where the geothermal heat utilization system is used for heating will be described.

Consider the case where a heating capacity of 30 kW / h is secured for 7 hours and COP 4.0 is achieved. In this case, the amount of heat energy (heat energy) supplied from the geothermal heat exchanger 10 to the heat pump unit 30 per hour is 22.5 kW. Therefore, in order to continue heating for 7 hours, it is sufficient that a total of 157.5 kW of heat can be supplied from the geothermal heat exchanger 10 to the heat pump unit 30.

^{The required amount (Ym 3} ) of the metal heat storage material 12 for enabling this amount of heat to be supplied from the geothermal heat exchanger 10 is calculated as follows.
Here, it is assumed that the room temperature of the temperature control target room 62 without heating is 6 ° C. and the temperature of the surrounding ground G is 15 ° C.
Further, the utilization efficiency of the heat energy stored in the geothermal heat exchanger 10 is 100%, and the metal heat storage material in the geothermal heat exchanger 10 is supplied by supplying heat from the geothermal heat exchanger 10 to the heat pump unit 30. It is assumed that the heat energy is used for heating without loss until the temperature of 12 (copper slag) drops from 15 ° C to 6 ° C.
Then, the amount of heat supplied from the geothermal heat exchanger 10 to the heat pump unit 30 from the start of operation of the geothermal heat utilization system to the end of consumption of the heat energy stored in the geothermal heat exchanger 10. A certain 157.5 kW = 3600 · Y (kg) × 0.2 (kcal / kg · ° C) × ((15 (° C) -6 (° C)) = 6480 · Y (kcal) = 6480 · Y / 860 (kW) ) = Approximately 7.5 · Y (kw).
Therefore, the required amount of the metal heat storage material 12 is Y (m ³ ) = about 157.5 / 7.5 = about 21 (m ³ ).
For example, when heating is performed using the geothermal heat utilization system for 7 hours at night in winter, the heat of the surrounding ground G is absorbed into the geothermal heat exchanger 10 by using the remaining 17 hours of the day. You just have to do it.

Actually, even during the operation of the geothermal heat utilization system, heat is supplied from the surrounding ground G to the geothermal heat exchanger 10 in parallel. Therefore, even by using a metal heat storage material 12 in an amount smaller than the amount obtained in the calculation here, a heating capacity of 30 kW / h can be secured for 7 hours and COP 4.0 can be achieved. Can be expected.

Here, the geothermal heat utilization system can be shared for cooling and heating, but in the above-mentioned two models, the amount of the metal heat storage material 12 required for cooling is 24 m ³ , and the metal required for heating. Since the amount of the heat storage material 12 was 21 m ³ , if the container 14 was filled with the metal heat storage material 12 of 24 m ³ , a cooling capacity or a heating capacity of 30 kW / h could be secured for 7 hours, and COP4. It turns out that 0.0 can be achieved.
Therefore, it is considered that the above-mentioned capacity of the model can be achieved by using the geothermal heat exchanger 10 of about 3 m cubic.

Further, in the above-mentioned model, the description is made on the premise that the heat pump unit 30 exchanges heat only with the geothermal heat exchanger 10, but the heat pump unit 30 is used as the heat pump unit 30 with and with the geothermal heat exchanger 10. If it is possible to use a structure capable of exchanging heat with the atmosphere, the required amount of the metal heat storage material 12 in the geothermal heat exchanger 10 can be further reduced as compared with the above-mentioned model. Be done.

According to the first embodiment as described above, since the metal heat storage material 12 has better heat dissipation than the liquid, it circulates in the first circulation pipe 21 as compared with the case where the container 14 is filled with water or the like. It is possible to realize a good heat exchange rate between the heat medium M and the surrounding ground G. Therefore, even in a relatively small-scale geothermal heat utilization system (relatively small-sized geothermal heat exchanger 10), it is possible to sufficiently secure the amount of heat that can be exchanged per unit time. Therefore, the geothermal heat utilization system can be suitably used for heating and cooling applications in general households.

When the heat pipe is directly buried in the ground as in the technique of Patent Document 2, the heat exchange capacity of each individual geothermal heat utilization system varies due to the influence of the installed ground, which is unstable. It becomes.
On the other hand, in the present embodiment, a part 25a of the second circulation pipe 25 for circulating the heat medium M is arranged in the metal heat storage material 12 filled in the container 14. Since the metal heat storage material 12 has a good thermal conductivity, even if there is temperature unevenness in the surrounding ground G due to variations in the properties of the soil in the surrounding ground G, geothermal heat exchange occurs. Heat exchange can be uniformly performed with the surrounding ground G throughout the vessel 10. That is, the metal heat storage material 12 functions as an intermediate heat storage material that eliminates the instability of the soil (which is the heat storage material). Therefore, the heat exchange capacity of each individual geothermal heat utilization system can be stabilized.

Further, when heat exchange is performed through a steel pipe as in the technique of Patent Document 2, since the amount of heat that can be exchanged depends on the thickness and length of the steel pipe, a large number of steel pipes are required to exchange a sufficient amount of heat. Need to be installed. On the other hand, in the present embodiment, the shape of the geothermal heat exchanger 10 is not particularly limited. Therefore, it is possible to easily design the shape of the geothermal heat exchanger 10 to an appropriate shape according to the amount of heat that needs to be replaced.

[Second Embodiment]
FIG. 3 is a schematic view showing the configuration of the geothermal heat utilization system according to the second embodiment.
FIG. 4 is a perspective view for explaining the geothermal heat exchanger 10 of the geothermal heat utilization system according to the second embodiment, in which (a) shows a concrete foundation 70 in which the recess 73 is formed. b) shows a state in which the geothermal heat exchanger 10 is constructed by filling the recess 73 with the metal heat storage material 12 or the like.

In the geothermal heat utilization system according to the present embodiment, the configuration of the container 14 is different from that of the first embodiment described above, and other configurations are the same as those of the first embodiment.

In the case of the present embodiment, by filling the recess 73 formed in the foundation structure (concrete foundation 70) of the building 60 with the metal heat storage material 12, the foundation structure constitutes the side peripheral wall portion and the bottom plate portion of the container 14. There is.

The top plate portion 16 of the container 14 is made of a metal plate or the like, and closes the opening at the upper end of the recess 73.
The top plate portion 16 may be made of a concrete plate or the like. In this case, the concrete plate may be precast concrete or may be formed by casting.

The inlet portion 21b and the outlet portion 21c of the first circulation pipe 21 project upward from the top plate portion 16, for example, respectively.

According to the present embodiment, the same effect as that of the first embodiment can be obtained, and the concrete foundation 70 has a function as a part (side peripheral wall portion and bottom plate portion) of the container 14 of the underground heat exchanger 10. Can be made.

[Third Embodiment]
FIG. 5 is a schematic view showing the configuration of the geothermal heat utilization system according to the third embodiment. In FIG. 5, the illustration of the building 60 having the temperature control target chamber 62 is omitted, and among the configurations of the building geothermal heat utilization system, the configuration of the building 60 side of the heat pump unit 30 is shown. It is omitted.

The geothermal heat utilization system according to the present embodiment is different from the geothermal heat utilization system according to the first embodiment in the following description, and is otherwise related to the first embodiment. It is configured in the same way as the geothermal heat utilization system.

In the present embodiment, the portion 21a of the first circulation pipe 21 is configured to include a plurality of branched portions (for example, branch portions 211 and 212 of two systems) branched from each other. The geothermal heat utilization system is configured so that the heat medium M circulates in parallel with each other at a plurality of branch portions.

As shown in FIG. 5, two systems of branch portions 211 and 212 are arranged in the container 14 of the geothermal heat exchanger 10. The branch portions 211 and 212 of each system have an inlet portion 21b at one end and an outlet portion 21c at the other end, and these inlet portions 21b and outlet portions 21c are located outside the container 14. It is protruding. For example, as shown in FIG. 5, the inlet portion 21b and the outlet portion 21c penetrate the side peripheral wall portion 15 of the container 14 and project to the outside of the container 14. However, the inlet portion 21b and the outlet portion 21c may penetrate the top plate portion 16 or the bottom plate portion 17 of the container 14 and project to the outside of the container 14.
In addition to the branch portions 211 and 212 (part 21a), the first circulation pipe 21 includes an outward path portion 21d that connects one end of the second circulation pipe 25 and each inlet portion 21b to each other, and each outlet portion 21c. The return path portion 21e, which connects the other end of the second circulation pipe 25 and the other end of the second circulation pipe 25 to each other, is included.
The branch portions 211 and 212 are arranged in different regions in the container 14. In the example of FIG. 5, the regions in which the branch portions 211 and 212 are arranged are different from each other in the vertical direction. Although not shown, the regions in which the branch portions 211 and 212 are arranged may have different positions in the horizontal direction.

Similar to the first embodiment, the area around the portion 21a (branched portions 211, 212) in the container 14 is filled with the metal heat storage material 12.

According to the present embodiment, in addition to the same effects as those of the first embodiment described above, the following effects can be obtained.
That is, since the branch portions 211 and 212 of the plurality of systems are arranged in the container 14 in a dispersed manner, the temperature in the container 14 changes locally when the geothermal heat utilization system is in operation. Can be suppressed. As a result, the geothermal energy stored in advance in the geothermal heat exchanger 10 can be efficiently used to the end.
Although FIG. 5 shows an example in which the number of branch portions is 2, a branch portion having 3 or more strains may be provided in one container 14.

[Fourth Embodiment]
FIG. 6 is a schematic view showing the configuration of the geothermal heat utilization system according to the fourth embodiment. In FIG. 6, the illustration of the building 60 having the temperature control target chamber 62 is omitted, and among the configurations of the building geothermal heat utilization system, the configuration of the building 60 side of the heat pump unit 30 is shown. It is omitted.

The geothermal heat utilization system according to the present embodiment is different from the geothermal heat utilization system according to the third embodiment in the following description, and is otherwise related to the third embodiment. It is configured in the same way as the geothermal heat utilization system.

In the case of the present embodiment, the geothermal heat utilization system includes a plurality of geothermal heat exchangers 10 and also includes a geothermal heat exchanger 10 that exchanges heat with and from a heat exchange unit (heat pump unit 30). Further, a switching means for switching (for example, a switching valve 31 and a control unit 32) is provided.

In the case of the present embodiment, in the geothermal heat utilization system, individual circulation paths 20 are formed corresponding to each of the plurality of geothermal heat exchangers 10.
In the example of FIG. 6, the geothermal heat utilization system includes two geothermal heat exchangers 10 of the geothermal heat exchangers 10a and 10b, and also has a circulation path 20a corresponding to the geothermal heat exchanger 10a. It is provided with a geothermal heat exchanger 10b and a corresponding circulation path 20b. The heat exchangers 10a and 10b in each region are connected to the heat pump unit 30 via the corresponding circulation paths 20a and 20b, respectively.

The switching valve 31 selectively selects the first state in which the heat medium M in the circulation path 20a is selectively circulated by the heat medium circulation pump unit 23 among the circulation paths 20a and 20b, and the heat medium M in the circulation path 20b. It is possible to switch between the second state of circulation by the heat medium circulation pump unit 23.

The control unit 32 functions as, for example, a ROM (Read Only Memory) that stores and holds a control program, a CPU (Central Processing Unit) that executes control processing according to the program, and a work area of the CPU. It is configured to include a RAM (Random Access Memory).
Further, the control unit 32 causes the switching valve 31 to switch between the first state and the second state according to a predetermined time schedule or according to a switching operation by the user.
As an example, it is conceivable to switch between the first state and the second state every other day. In this case, the local heat exchanger 10 can be used for cooling or heating every other day, and it is possible to secure sufficient time to store the geothermal energy in the local heat exchanger 10. Become.
By appropriately changing the number and capacity of the geothermal heat exchangers 10, the geothermal heat utilization system can be configured to be able to operate for 24 hours.

[Fifth Embodiment]
FIG. 7 is a schematic view showing the configuration of the geothermal heat utilization system according to the fifth embodiment. In FIG. 7, the illustration of the building 60 having the temperature control target chamber 62 is omitted, and among the configurations of the building geothermal heat utilization system, the configuration of the building 60 side of the heat pump unit 30 is shown. It is omitted.

The geothermal heat utilization system according to the present embodiment is different from the geothermal heat utilization system according to the first embodiment in the following description, and is otherwise related to the first embodiment. It is configured in the same way as the geothermal heat utilization system.

In the case of the present embodiment, the container 14 includes a plurality of filling regions each in which the metal heat storage material 12 is hermetically filled, and a partition portion 18 composed of a heat insulating material and partitioning the plurality of filling regions from each other. ing. Then, individual circulation paths 20 are formed corresponding to each of the plurality of filling regions.
A part of the corresponding circulation path 20 (for example, a part 21a of the first circulation pipe 21) is arranged in each of the plurality of filling regions.
The geothermal heat utilization system includes switching means (for example, a switching valve 31 and a control unit 32) for switching a filling region for heat exchange with the heat pump unit 30 among a plurality of filling regions.

In the example of FIG. 7, the geothermal heat utilization system includes two filling regions 14a and 14b, a circulation path 20a corresponding to the filling region 14a, and a circulation path 20b corresponding to the filling region 14b. , Is equipped. A part 21a of the first circulation pipe 21 arranged in each of the filling regions 14a and 14b is connected to the heat pump unit 30 via the corresponding circulation passages 20a and 20b, respectively.

The positions of the filling regions 14a and 14b may be different from each other in the horizontal direction or may be different from each other in the vertical direction. In the example of FIG. 7, the geothermal heat exchanger 10 shows a plan cross section thereof, and shows a case where the positions of the filling regions 14a and 14b are different from each other in the horizontal direction.

The switching valve 31 selectively selects the first state in which the heat medium M in the circulation path 20a is selectively circulated by the heat medium circulation pump unit 23 among the circulation paths 20a and 20b, and the heat medium M in the circulation path 20b. It is possible to switch between the second state of circulation by the heat medium circulation pump unit 23.
Further, the control unit 32 causes the switching valve 31 to switch between the first state and the second state according to a predetermined time schedule or according to a switching operation by the user.
As an example, it is conceivable to switch between the first state and the second state every other day. In this case, each of the filling areas 14a and 14b can be used for cooling or heating every other day, and it is possible to secure sufficient time for storing geothermal energy in each of the filling areas 14a and 14b. Become.
Further, by appropriately changing the number and capacity of the filling regions 14a and 14b, the geothermal heat utilization system can be configured to be able to operate for 24 hours.

It should be noted that each of the above embodiments can be combined as appropriate.

<Modification example 1>
For example, the geothermal heat utilization system when the third embodiment (FIG. 5) and the fifth embodiment (FIG. 7) are combined has the following configuration.
That is, this geothermal heat utilization system includes a plurality of systems of circulation paths 20 (including branch portions 211 and 212, respectively), and these circulation paths 20 are, for example, in the horizontal direction (for example, in front of the paper in FIG. 5). They are arranged at different positions in the direction from to the back). A portion 21a of the first circulation pipe 21 of each circulation path 20 is arranged in the common container 14, and a region in which the part 21a of each first circulation pipe 21 is arranged is a partition portion 18 (FIG. FIG. They are separated from each other via 7).
Then, the heat medium M in the circulation path 20 of any one of the circulation paths 20 of the plurality of systems is selectively circulated by the switching means composed of the switching valve 31 and the control unit 32 (FIG. 7).
With this configuration, the effects of the third embodiment and the fifth embodiment can be obtained.

<Modification 2>
Alternatively, the geothermal heat utilization system may have a configuration in which the fourth embodiment (FIG. 6) and the fifth embodiment (FIG. 7) are combined.
In this case, the local heat exchangers 10a and 10b have the configuration of the above-mentioned modification 1, and in the underground heat utilization system, a plurality of circulation paths 20 are connected for each of the local heat exchangers 10a and 10b. The configuration is as follows.
With this configuration, the effects of the fourth embodiment and the fifth embodiment can be obtained.

Further, in each of the above forms, an example of cooling or heating by radiative cooling or radiant heat has been described, but the geothermal heat utilization system is an indoor unit that blows air cooled or heated by radiative cooling or radiant heat. You may also have more.

The above embodiment includes the following technical ideas.
(1) A part of a circulation path for circulating a heat medium is provided inside and a geothermal heat exchanger buried in the ground is provided, and the geothermal heat exchanger is provided via the geothermal heat exchanger. A geothermal heat utilization system that collects heat from the surrounding ground or dissipates heat to the surrounding ground.
The geothermal heat exchanger is a geothermal heat utilization system comprising a container that is resistant to corrosion against the soil in the surrounding ground and a metal heat storage material that is hermetically filled in the container.
(2) The geothermal heat utilization system according to (1), wherein the metal heat storage material contains copper slag.
(3) The geothermal heat utilization system according to (1) or (2), wherein the container is made of a material having a higher thermal conductivity than the metal heat storage material.
(4) Any of (1) to (3), wherein the container is made of a resin material containing chromium, stainless steel, a corrosion-resistant iron-based material, or a carbon fiber material. The geothermal heat utilization system described in item 1.
(5) The geothermal heat utilization system according to any one of (1) to (4), wherein the outer surface of the container is uneven.
(6) The geothermal heat utilization system according to (5), wherein the outer surface of the side peripheral wall portion of the container is formed with irregularities having a wavy flat cross-sectional shape.
(7) By filling the recess formed in the foundation structure of the building with the metal heat storage material, the foundation structure constitutes a side peripheral wall portion and a bottom plate portion of the container (1). Or the geothermal heat utilization system according to (2).
(8) Equipped with a water-type air conditioner that circulates circulating water in the piping installed on the ceiling or under the floor of the temperature control target room.
The water type air conditioner
A heat exchange unit that exchanges heat by bringing the heat medium into thermal contact with the circulating water.
A heat medium circulation pump unit that circulates the heat medium in the circulation path, and
Have,
The underground according to any one of claims (1) to (7), wherein the circulation path circulates the heat medium between the heat exchange unit and the geothermal heat exchanger. Heat utilization system.
(9) In addition to being equipped with a plurality of the above-mentioned geothermal heat exchangers,
The geothermal heat utilization system according to (8), further comprising a switching means for switching the geothermal heat exchanger that exchanges heat with the heat exchange unit.
(10) Each of the containers includes a plurality of filling regions in which the metal heat storage material is hermetically filled, and a partition portion formed of a heat insulating material and partitioning the plurality of filling regions from each other.
An individual circulation path is formed corresponding to each of the plurality of filling regions, and the circulation path is formed.
Each of the plurality of filling regions is disposed with the portion of the corresponding circulation path.
The geothermal heat utilization system is characterized in that it includes a switching means for switching a filling region for heat exchange with the heat exchange unit among the plurality of filling regions (8) or (9). The geothermal heat utilization system described.
(11) The part of the circulation path is configured to include a plurality of branched portions branched from each other.
The geothermal heat utilization system according to any one of (8) to (10), wherein the heat medium is configured to circulate in parallel with each other at the plurality of branched portions.
(12) The item according to any one of (1) to (11), wherein the lower surface of the underground heat exchanger is located at a place where the depth of the surrounding ground from the ground surface is shallower than 20 m. The geothermal heat utilization system described.
(13) A geothermal heat exchanger in which a part of a pipe that communicates with each other at both ends is disposed inside and is used by being buried in the ground to collect heat from the surrounding ground or dissipate heat to the surrounding ground. And
A geothermal heat exchanger comprising a container that is resistant to corrosion against the soil of the surrounding ground and a metal heat storage material that is hermetically filled in the container.
(14) Each of both ends of the pipe protrudes from the container.
The geothermal heat exchanger according to (14), wherein flange portions are formed at the tips of both ends of the pipe.

10, 10a, 10b Geothermal exchanger 12 Metal heat storage material 14 Container 14a, 14b Filling area 15 Side peripheral wall part 16 Top plate part 17 Bottom plate part 18 Partition part 20, 20a, 20b Circulation path 21 First circulation pipe 21a Part 21b Inlet 21c Outlet 21d Outward 21e Return 22, 24 Flange 23 Heat medium circulation pump 25 Second circulation pipe 25a Part 30 Heat pump unit (heat exchange unit)
31 Switching valve (switching means)
32 Control unit (switching means)
41, 43 On-off valve 45, 47 Piping 47 Piping 48 Pump 49 Pump 51 Ceiling radiation pipe (Piping)
53 Underfloor radiation pipe (piping)
55 Water drop receiver 60 Building 62 Temperature control room 64 Ceiling 66 Underfloor 70 Concrete foundation (foundation structure)
73 Recesses 111, 112, 113, 114, 115, 116, 117, 118 Columnar members 171, 172, 173, 174, 175, 176, 177, 178 Plate-shaped members 211, 212 Branch part G Surrounding ground M Heat medium W Circulating water

Claims (7)

A part of the circulation path for circulating the heat medium is provided inside and the geothermal heat exchanger is buried in the ground, and the ground around the geothermal heat exchanger is provided via the geothermal heat exchanger. A geothermal heat utilization system that collects heat from the ground or dissipates heat to the surrounding ground.
The geothermal heat exchanger has a container that is resistant to corrosion against the soil in the surrounding ground and a metal heat storage material that is hermetically filled in the container.
The circulation path is a circulation pipe that circulates the heat medium inside.
A part of the circulation pipe passes through the inside of the container and
Inside the container, the area around the circulation pipe is filled with the metal heat storage material .
The container is made of a material having a higher thermal conductivity than the metal heat storage material.
The geothermal heat utilization system is
Equipped with a water-type air conditioner that circulates circulating water in the piping installed on the ceiling or under the floor of the temperature control target room.
The water type air conditioner
A heat exchange unit that exchanges heat by bringing the heat medium into thermal contact with the circulating water.
A heat medium circulation pump unit that circulates the heat medium in the circulation path, and
Have,
The circulation path circulates the heat medium between the heat exchange unit and the geothermal heat exchanger.
The geothermal heat utilization system is
In addition to being equipped with the multiple geothermal heat exchangers
A geothermal heat utilization system further comprising a switching means for switching the geothermal heat exchanger that exchanges heat with the heat exchange unit. The geothermal heat utilization system according to claim 1, wherein the metal heat storage material contains copper slag. The geothermal heat utilization system according to claim 1 or 2 , wherein the container is made of a resin material containing chromium, stainless steel, a corrosion-resistant iron-based material, or a carbon fiber material. .. The geothermal heat utilization system according to any one of claims 1 to 3 , wherein the outer surface of the container is formed with irregularities. The geothermal heat utilization system according to claim 4 , wherein the outer surface of the side peripheral wall portion of the container is formed with irregularities having a corrugated flat cross-sectional shape. The part of the circulation path is composed of a plurality of branches branched from each other.
The geothermal heat utilization system according to any one of claims 1 to 5 , wherein the heat medium is configured to circulate in parallel with each other at the plurality of branch portions. The geothermal heat according to any one of claims 1 to 6 , wherein the lower surface of the underground heat exchanger is located at a depth of less than 20 m from the ground surface of the surrounding ground. Usage system.

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