JP3069549B2 - Manufacturing method of geothermal hot spring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a geothermal hot spring which is not a hot spring (natural hot spring) according to the hot spring method, but uses underground water as hot water by utilizing geothermal heat.

[0002]

2. Description of the Related Art Hot springs are defined as hot water, mineral water, steam, and other gases (excluding natural gas mainly composed of hydrocarbons) that escape from the ground under the hot spring method. A substance having a temperature of 25 degrees Celsius or higher or a substance in an amount of 1 Kg or more specified in mineral water ". Therefore, in order to get a hot spring, you have to dig a well and find a source.

[0003] In order to permanently protect and use hot spring resources, prefectural governments have set up special hot spring protection areas and hot spring protection areas, and restrictions on excavation in these areas have been established. For example, in Aomori Prefecture, land excavation for the purpose of letting out hot springs is not allowed in the special hot spring protected area in principle, and land excavation in the hot spring protected area within a straight line distance of 800 m or less between the source is in principle allowed. I can't. Further, even when excavating land for the purpose of collecting groundwater, there are restrictions as shown in Tables 1 and 2 on the excavation depth.

[0004]

[Table 1]

[0005]

[Table 2]

[0006]

While the protection of hot spring resources has been attempted as described above, on the other hand, due to the recent hot spring boom, further use of hot springs has been demanded. However, if the hot spring excavation is performed in darkness, the hot spring may be depleted.

There is also the problem of empty wells. Excavation of hot springs is very costly, so it is necessary to carefully select the right place through repeated test boring and pumping tests. However, even when it is determined that the hot spring is in the right place due to the spring, when the unexpected water content is low or the amount used is large, the hot spring may eventually be depleted. In addition, water quality is poor in terms of taste, smell, turbidity, gas, acidity, and the like, so that it may not be used. In such a case, the development cost, which is said to cost tens of millions to hundreds of millions of yen, is not only wasted, but also adversely affects the tourism industry and the like that have been raised.

[0008] Further, if boiling water is used to solve the above-mentioned problems, there is a drawback that a large amount of energy is consumed and a large amount of carbon dioxide, which is a cause of global warming, is released.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and to stably and surely provide hot water equivalent to that of a hot spring and effectively protect the environment.

[0010]

Means for Solving the Problems] For the purpose achieved, state method for producing a geothermal hot water fountain according to the present invention, in the outer casing which is inserted from the ground up to the geothermal source, which resides apart the inner casing The outer pumping passage portion is formed at the above interval, the inner pumping passage portion formed in the inner hole of the inner casing communicates with the outer pumping passage portion, the outer pumping passage portion and the inner pumping passage portion. Top of
And an intake port is provided on a peripheral wall of the outer casing, and groundwater collected from the intake port is heated by geothermal heat while passing through the outer pumping passage section and taken out from the inner pumping passage section. The method for manufacturing a geothermal hot spring according to claim 1, wherein the communicating portion between the outer pumping passage portion and the inner pumping passage portion is a pumping-in portion formed by a communicating hole provided at the bottom of the inner casing.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a geothermal hot spring according to the present invention will now be described in more detail with reference to the drawings showing an embodiment. Reference numeral 1 denotes an outer casing, which is formed by connecting a number of casing tubes (not shown) which are made of a material having a high thermal conductivity, such as steel and copper, and which are open at the top and bottom. The outer casing 1 is provided with only a casing bottom constituting a lower end portion and provided with a pit bottom 3, an outer opening 5 is opened, and is inserted into a drilling hole 7 which is deeply excavated in the ground up to a high-temperature tropical zone H serving as a geothermal source. I do. Excavation is performed in a region where the geothermal structure of the underground is already known, using a well-known investigation method such as a method of measuring a temperature inside a hole, an electric logging method, and a geophysical exploration method.

The high geothermal layer is at a different depth depending on the geothermal source. That is, the geothermal source is a volcanic geothermal source derived from underground magma energy, a non-volcanic geothermal source derived from frictional heat due to fault motion, heat of chemical reaction, heat due to radioactivity, etc. Groundwater (ie,
Underground geothermal source derived from the energy of hot springs)
Each of them has different emission energy. In general, the former has a large emission energy, and the latter has a small energy. Therefore, the depth of the excavation hole 7 differs depending on the geothermal source at the excavation site. In the case of a groundwater source, it is generally said that the rate of rise in underground temperature in Japan increases by about 4 ° C. every time a depth of 100 m is excavated. There is).
Therefore, since geothermal heat is surely increased with the excavation, it is not necessary to repeat test boring and pumping tests in this excavation. Reference numeral 11 denotes an inner casing, which is inserted inside the outer casing 1 with a space therebetween, and forms the outer pumping passage 9 by the space. The inner casing 11 is made of resin,
An upper and lower open casing tube (not shown) made of a material having high heat insulation efficiency such as a molded product of ceramic, pulp, glass fiber or the like is connected in a line shape to form an inner pumping passage portion 12 in the inner hole. . The inner casing 1
1 is provided with a pumping introduction section 13 comprising a large number of communication holes 15 at the bottom of only the casing tube constituting the lower end.

The outer casing 1 has a water intake port 17 formed on the peripheral wall thereof and includes a plurality of strainer holes 16. The intake 17 is an aquifer B in the stratum A where the water temperature is lower than 25 ° C.
And the groundwater 19 is taken in. G in the figure. L. Is a ground line, U. G. FIG. Indicates an underground line,
L. Is the pumping water level, N. L. Indicates natural water level.

Thus, groundwater 19 is collected from the intake 17. The groundwater 19 travels downward in the outer pumping passage 9 as indicated by the arrow, and as it proceeds downward, the water temperature rises due to the effect of geothermal heat during the passage of the warm tropics W and the hot tropics H.

In the case of an underground geothermal source, the depth is usually deep, so that even if there is a geological layer having a low geothermal temperature in the middle of the outer pumping passage section 9, for example, in the upper layer, it becomes larger as it goes down. Because it is heated by geothermal energy, it is practically unaffected by low geothermal layers. The water intake temperature is often set to 100 ° C. or lower for convenience of use. For example, when water is to be taken at about 40 ° C to 43 ° C, excavation is usually performed to a depth of about 2,000 m. In such a case, the geothermal temperature near the bottom is about 80 ° C to 87 ° C. The hot water, that is, the geothermal hot water spring 19a is moved from the pumping introduction portion 13 of the inner casing 11 to the inner casing 1 by the water pressure of the subsequently supplied groundwater 19.
1 penetrates into the inner pumping passage 12. Therefore, the pump 20 installed in the inner pumping passage 12 is operated,
The geothermal hot spring 19a that has entered the inner casing 11 via the water pump 21 is pumped up and taken out from the outlet 22.

[0016] The water intake temperature is determined by the temperature and amount of the injection water,
The excavation depth is designed so as to have a desired water intake temperature because it is affected by the volume and thermal conductivity of the outer casing 1, the heat insulation efficiency of the inner casing 11, the amount of heat released from the geothermal source, and the like.

According to the above-described embodiment, since hot springs of 25 ° C. or higher are not collected, there is a problem of the hot spring law and the restrictions on hot spring collection by the hot spring special protection areas and hot spring protection areas set in prefectures. Absent. Therefore, hot water (geothermal hot spring) comparable to a natural hot spring can be freely obtained without worrying about depletion of hot spring resources.

The geothermal heat is surely increased with the excavation, and the geothermal hot spring 19a according to the present invention is heated by using this geothermal heat. It is possible to avoid depletion of hot springs due to presence or absence of water content, measurement error of water content, excessive use, etc., problems of water quality of waste water, and various losses resulting from these.

Further, since the heating source is natural geothermal, there is no possibility of causing various problems due to energy consumption.

The method of manufacturing a geothermal hot spring according to the present invention is not limited to the above embodiment. For example, the casing tube constituting the outer casing 1 is not limited as long as it is made of a material having high thermal conductivity. Further, the casing tube constituting the inner casing 11 may be made of any material as long as it is made of a material having high heat insulation efficiency. Furthermore, the inner casing 11 may be inserted with a space between the outer casing 1 and the inner casing 11, and the inner casing 11 does not necessarily have to be provided coaxially with the outer casing 1.

The mode of taking out the geothermal hot spring is optional. For example, the geothermal hot spring may be taken out by a water supply pressure of a water supply pump without using a water pump.

[0022]

As described above, according to the method of manufacturing a geothermal hot spring according to the present invention, it is possible to stably and reliably provide hot water equivalent to a hot spring and effectively protect the environment.

[Brief description of the drawings]

FIG. 1 is a front sectional view illustrating a method of manufacturing a geothermal hot spring according to the present invention.

FIG. 2 is an enlarged plan view of FIG.

FIG. 3 is an enlarged view of a part III in FIG. 1;

FIG. 4 is an enlarged view of an IV section in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer casing 3 Downhole 5 Outer opening 7 Drilling hole 9 Outer pumping passage 11 Inner casing 12 Inner pumping passage 13 Pumping introduction part 15 Communication hole 16 Strainer hole 17 Intake 19 Groundwater 19a Geothermal hot spring 20 Pumping pump 21 Lifting Hot water pipe 22 outlet

Claims (2)

(57) [Claims] (1) An inner casing is provided at intervals in an outer casing inserted from the ground to a geothermal source.
The outer pumping passage portion is formed at the above interval, and the inner pumping passage portion formed in the inner hole of the inner casing communicates with the outer pumping passage portion.
The upper part of the inner pumping passage is opened , an intake is provided on the peripheral wall of the outer casing, and groundwater collected from the inlet is heated by geothermal heat while passing through the outer pumping passage, and the inner pumping passage is heated. A method for manufacturing a geothermal hot spring characterized by extracting from a hot spring. 2. The method for manufacturing a geothermal hot spring according to claim 1, wherein the communicating portion between the outer pumping passage portion and the inner pumping passage portion is a pumping introduction portion including a communication hole provided at a bottom portion of the inner casing. The method of manufacturing a geothermal hot spring.