JPH0413586Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a low-temperature storage facility that cools a storage space formed in the ground by forming a frozen layer using a heat pipe.

"Prior Art" Generally, when storing grains such as rice, food, etc., it is required to store them in an environment of constant low temperature and low humidity.

Conventionally, this type of storage facility has been applied, for example, to a low-temperature storage warehouse that uses a refrigerator to maintain the interior at a constant temperature, but the equipment cost (initial cost) and running cost are high. is becoming high.

``Problems that the invention seeks to solve'' Therefore, as a result of intensive research to solve these problems, the present applicant and others have found that they can store cold energy in the winter in the form of frozen soil and use it during the warm summer months. If supplied, compared to storage using conventional refrigerators,
We came up with the idea that the initial cost and running cost would be low, and we have already developed a low-temperature storage facility (Japanese Patent Application No. 60-285122 (Japanese Patent Application Laid-open No. 62-285-120) as shown in Figure 5.
142973)).

This is done by using the excavated hole 1 excavated on the surface of the ground G, which opens to the outside air, as a storage location, and the heat pipe 10 buried in the ground G around the excavated hole 1.
This is a low-temperature storage facility that cools the inside of the drill hole 1 by freezing the inside of the drill hole 1, and a roof 7 that covers the top surface of the drill hole 1 is arranged on the ground around the drill hole 1. The side wall portion 3 is formed into an inclined surface that slopes upward as it approaches the opening of the excavated hole 1, and the heat pipe 10 has a lower end 10b along the side wall portion 3 of the excavated hole 1. It is characterized by extending to the lower part of the floor of the excavated hole 1.

By the way, in the case of the above-mentioned low-temperature storage, supercooled outside air energy can be stored as frozen soil F and ice in the ground around the excavation hole 1 in the winter, and conversely, the cold heat can be stored in the warm spring and summer months. It has an excellent effect of keeping the inside of the excavation hole 1 at a low temperature by using it, but since the upper part of the storage is a roof, even if it is made of insulation. However, it cannot be expected to serve as a source of cooling or heat, and therefore the upper part of the refrigerator near the roof is difficult to cool.
There were some issues that needed to be improved, such as the uneven temperature distribution inside the refrigerator. In addition to this,
There was a problem in that constructing the roof 7 as a heat insulator was expensive.

"Means for Solving the Problems" The low temperature storage according to the present invention uses a shielded space formed in the ground as a storage location, and forms frozen soil using heat pipes buried in the soil layer forming the periphery of the space. The space is cooled, and the entire periphery of the space is formed of a layer of hydrated soil with high water retention, and the heat pipe is wrapped around the space up and down, with both ends exposed to the outside air. It is buried in the water-containing soil layer.

"Function" According to the above configuration, supercooled outside air energy can be stored as frozen soil and ice in the soil layer around the storage space in the winter, and this cold stored thermal energy can be used in the warm spring and summer seasons. This allows the storage space to be kept at a low temperature and with a uniform temperature distribution.

``Example'' Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 shows a front sectional view of a low-temperature storage A according to the present invention, and the reference numeral 1 in the figure is an excavated hole formed by excavating the ground G. The excavated hole 1 is formed so that the direction perpendicular to the paper surface in the figure is the longitudinal direction. A water-shielding sheet 4 is laid on the bottom surface 2 and side walls 3 of the excavated hole 1 so as to uniformly cover them.

Inside the excavated hole 1 on which the water-shielding sheet 4 is laid, a hydrated soil layer 5 is formed of hydrated soil 5a with high water retention. A hollow space 6 extending along the direction is formed. In other words, the entire periphery of the space 6 is surrounded by the hydrated soil 5a, and this space 6 is used to store food and other items 9.
It serves as a storage space for cooling and storing. The inner wall of the space 6 is a water-blocking wall 8 integrally formed of concrete, a liner plate, or the like to prevent water from entering the inner space 6. In addition, the hydrated soil 5a
The water to be impregnated into the water is preferably one in which a substance having a high freezing point effect, such as sodium chloride, is dissolved. More preferably, the water-containing soil layer 5
As the hydrated soil 5a constituting the lower part of the space 6, the volume does not change significantly even when frozen.
Use what is called a small frozen soil. In this case, when the hydrated soil 5a freezes, it is possible to suppress the phenomenon that the soil is lifted up, and to reduce the adverse effect on the impermeable wall 8 surrounding the space 6.

The water-containing soil layer 5 includes this water-containing soil layer 5
A heat pipe 10 that cools the space 6 by freezing the heat pipe 10 is buried so as to wrap around the space 6 in the vertical direction and have both ends protrude into the outside air. This heat pipe 10 has a space 6
are arranged in parallel at equal intervals along the longitudinal direction.

The heat pipe 10 is configured such that a working fluid is sealed in a long cylindrical airtight container 11 that is sufficiently deaerated, and heat transfer occurs as the fluid changes phase. The heat pipes 10 surrounding the space 6 above and below are buried in such a manner that they intersect at the top of the space 6 and partially wrap before projecting to the outside air. Furthermore, a plurality of fins 12 are provided protruding along the length of both ends (tips) of the heat pipe 10 exposed to the outside air to increase the efficiency of heat exchange.

In the figure, reference numeral 13 indicates a heat insulating material laid on the surface of the hydrated soil layer 5, and is especially provided when the outside temperature is high, such as in summer.

Next, a method of implementing and using the low-temperature storage A constructed as described above will be explained.

As shown in FIG. 1, in order to construct this low-temperature storage A, first, the surface of the ground at the storage location is excavated to form an excavated hole 1, and then a water-blocking sheet 4 is laid inside this excavated hole 1. . The water-blocking sheet 4 should be wide enough to uniformly cover the bottom surface 2 and side walls 3 of the excavated hole 1, and so that its end reaches the ground surface from the opening of the excavated hole 1. do.

Next, the bottom of the excavated hole 1 in which the water-blocking sheet 4 has been laid is backfilled with water-containing soil 5a. The height of backfilling at this time is from the bottom of the excavated hole 1 to the water-blocking wall 8.
Approximately half the dimension to the bottom of the

Once the above-mentioned initial backfill has been constructed, as shown in FIG. Backfilling with water-containing soil 5a is performed again so that the bottom portion is buried until about one-third of the excavated hole 1 is filled. As mentioned above, it is desirable that the water-containing soil 5a used for backfilling up to this point be one with low frozen soil properties.

Once this state is reached, the pre-assembled water-shielding wall 8 is placed on the backfilled hydrated soil 5a, and then the heat pipe 10 is connected to the water-shielding wall 8.
The surrounding area is backfilled while being bent so that it surrounds it at a predetermined interval.
At this time, the heat pipes 10 are crossed at the upper part of the water-shielding wall 8 so that they are sufficiently disposed there. In addition, backfilling with hydrated soil 5a is
Construction is performed so that the intersection of the water-shielding wall 8 and the heat pipe 10 is sufficiently buried. After that, a heat insulating material 1 is placed on the surface of the water-containing soil layer 5, which is formed as necessary.
3 to complete the cold storage A as shown in Fig. 1.

To use the low-temperature storage A having such a configuration, first, in winter, the upper part of the heat pipe 10 is cooled with cold air, and frozen soil F is formed around the heat pipe 10 to store supercooled outside air energy. That is, when the upper part of the heat pipe 10 is cooled by cold air in winter, the working fluid in the heat pipe 10 condenses and liquefies, and flows down the pipe wall due to gravity. As a result, cold heat is carried to the lower part of the heat pipe 10 by this carried cold heat.
The surrounding hydrous soil layer 5 is frozen, and frozen soil F is formed around the heat pipe 10, as shown in FIG. This phenomenon is repeated in winter, and frozen soil F is formed around the heat pipe 10, and supercooled outside air energy (cold energy) is stored in the form of frozen soil F and ice in the hydrated soil layer 5. be.

On the other hand, in the warm spring and summer months, cold stored thermal energy is released into the frozen ground F, and the inside of the space 6 is maintained at a low temperature.

According to the low-temperature storage A with the above structure and operation, the space 6 provided in the center of the water-containing soil layer 5 formed by backfilling after excavating the ground is used as a storage location, and the heat pipe 10 is simply arranged around the space 6. The initial cost can be reduced because the heat pipe 10 is maintenance-free, and the frozen soil F and ice are formed, so the running cost is almost negligible. significantly reduced. Furthermore, in addition to this, the space 6 serving as the storage location has a water-containing soil layer 5 formed all around it, especially the upper part, and a heat pipe 10 is placed there, so that the entire space 6 is Frozen soil F will be formed around it. As a result, the entire circumference of the space 6 becomes a constant cold source of 0°C or lower,
It is possible to make the temperature distribution in the space 6 uniform and maintain that state, thereby making it easier to control the temperature inside the refrigerator. In addition, one unit of heat pipe 1
0, instead of using two wires and dividing the left and right parts separately as shown in Fig. 5, by constructing this with one wire as in the embodiment, the processing effort for both ends can be reduced by about half. , economical. Note that the lowermost end of the heat pipe 10 becomes a reservoir of condensed working fluid, so there is a risk that the cooling capacity will be reduced. In order to prevent this, as shown in FIG. 4, a loop 15 may be formed at the lowermost end and the condensed working fluid may be stored in this loop.

Further, in this embodiment, the upper part of the low temperature storage A is slightly raised from the surface of the ground G, but this is related to the excavation depth of the excavation hole 1, for example. It is also possible to make the upper surface of the low temperature storage A flush with the ground surface of the ground G by making it deeper than that of the embodiment.

"Effect of the invention" As explained above, the low temperature storage according to the invention uses a shielded space formed in the ground as a storage location, and forms frozen soil using heat pipes buried in the soil layer surrounding the space. The space is cooled, and the entire periphery of the space is formed of a layer of hydrated soil with high water retention, and the heat pipe is wrapped around the space up and down, with both ends exposed to the outside air. Therefore, after excavating the ground and backfilling, the space created in the center of the water-containing soil layer was used as a storage location, and heat pipes were placed around it. The initial cost can be reduced, and maintenance-free heat pipes can be used to utilize the cold air of winter to reduce the initial cost.
Since it forms frozen soil and ice, running costs are significantly reduced to the point where it is almost no burden. Furthermore, in addition to this,
Since the storage space has a hydrated soil layer formed all around it, especially the upper part, and heat pipes are arranged, frozen soil is formed all around the space. Therefore, the entire circumference of the space becomes a constant cold source of 0°C or lower, keeping the storage space in a constant low temperature state and uniform temperature distribution, making it easy to control the temperature inside the refrigerator. It has excellent effects such as

[Brief explanation of the drawing]

1 to 3 each show an embodiment of the present invention, in which FIG. 1 is a front sectional view of a low temperature storage A, FIG. Figure 3 is a front sectional view showing the formation of frozen soil F. FIG. 4 shows a modified embodiment of the present invention, in which a front sectional view of a low temperature storage A is shown, and FIG. 5 is a front sectional view of a low temperature storage previously filed by the present applicant. A...Cold storage, F...Frozen soil, G...Ground,
1... Excavation hole, 4... Water-blocking sheet, 5... Water-containing soil layer, 5a... Water-containing soil, 6... Space, 8... Water-blocking wall, 10... Heat pipe, 13... Heat insulation material .

Claims (1)

[Scope of utility model registration request] The shielded space formed in the ground is used as a storage area.
A low-temperature storage facility in which frozen soil is formed and cooled in the space by heat pipes buried in a soil layer forming the periphery of the space, the entire periphery of the space being formed of a hydrated soil layer with high water retention, and The low-temperature storage facility is characterized in that the heat pipe is buried in the water-containing soil layer in a form that wraps around the space up and down and exposes both ends to the outside air.