JPH0336396A - Great depth hot spring water pumping plant preventing lowering of temperature of same water - Google Patents

Abstract

PURPOSE:To reduce the equipment cost and operation control cost of the plant stated in the subject by covering a casing pipe with a heat insulating material from the ground to a solid rock layer so as to prevent heat radiation of hot spring water at a cool water layer, the casing pipe having a submergible pump provided at its end and having a hot water pump inserted therein. CONSTITUTION:An outer pipe 4 is embedded into the ground and passed through a solid rock layer B, and a casing pipe 1' is inserted into the pipe 4 so that it reaches a high temperature water layer C. A non-water-absorbing heat insulating material 5 is packed in an annular space between the outer pipe 4 and the casing pipe 1'. A hot water pipe 3 having a submergible pump 2 provided at its end is inserted into the casing pipe 1'. Thus, hot spring water pumped via the hot water pump 3 is prevented from being cooled during pumping and its reheating temperature is lowered, and also the device is miniaturized so that the equipment cost and control cost are greatly reduced.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to hot water pumping facilities for hot spring wells,
It is effective when used to raise the temperature of hot water in deep hot spring wells.

[Prior Art and Section M of the Present Invention] The internal structure of a conventional deep hot spring well/door is schematically shown in FIG. This conventional hot spring well is 1000m underground
The high-temperature water is brought up to the ground from the high-temperature water layer under the rock 11B by a submersible pump via the hot water pipe 3. In this well, the diameter from the high temperature water layer C to the ground is 1
50mm diameter inside 50mm large diameter casing pipe l
A hot water pump 3'jtm is inserted into the tank, and a submersible pump 2 is attached to its lower end. The total length of this hot water pipe 3 is slightly above the strainer position where the maximum slit is provided.

The hot water in the high-temperature water layer C rises within the casing pipe 1 to above the submersible pump 2 due to its underground pressure. Therefore, by lowering the submersible pump to a maximum depth slightly above the above-mentioned 1-Lehner position, it is possible to withdraw high-temperature water from the high-temperature water layer C at a depth of 1000 m or more to the ground.

In the case of deep hot springs, the temperature of the high-temperature water layer is generally not very high, and the pumped water temperature is often around 30 degrees because it is brought up to the ground through a long pipe.
Since it can hardly be used as it is, it is heated in a boiler and used for baths, hot water for heating, etc.

If the pumped water temperature does not reach 40 degrees, please use the facility for reheating! However, since facility maintenance and operation management costs are large, if the pumped water temperature could be raised by several degrees, these costs would be greatly reduced, so it is strongly desired to raise the pumped water temperature even a little.

Even if the temperature of the hot water in the high-temperature water layer reaches 40 degrees, the temperature of the hot water pulled up from the pumping pipe drops to around 30 degrees. This is because the hot water is cooled while rising inside the casing pipe l, which is cooled by the layer above the bedrock, that is, the cold water layer A several hundred meters deep. Lifting pipe 3 has a diameter of 50m
m, whereas the casing pipe has a diameter of 150 mm.
It has a large diameter. Therefore, the heat exchange area between the cold water in the cold water layer A outside the casing pipe and the hot water inside the casing pipe is large, the speed at which the hot water rises inside the casing pipe is low, and the distance it rises is extremely long, several hundred meters. , is the main cause that promotes the temperature drop of hot water rising inside the casing pipe.

The present invention minimizes heat radiation to the cold water layer A during rising of the hot spring water casing pipe.

The objective is to reduce the heat loss of hot spring water (increase the pumped water temperature).

[Means taken to solve the problem] The measures taken to solve the above problem are to make the casing pipe a hollow double insulated pipe, and to make the heat insulating layer of the insulated pipe long enough to reach the bedrock layer.

In addition, in order to prevent groundwater from entering the gap between the inner pipe and outer pipe of the hollow double casing pipe, and to reduce the heat conductivity of both pipes, insulation material is filled to prevent the hollow double casing pipe from becoming an insulated pipe. shall be.

[For production]

The inner pipe of hollow double insulated casing pipe is conventional (Fig. 1)
The casing pipe is similar to the casing pipe of a well, and the depth to which the submersible pump is lowered is the same as that of a conventional well, so the speed and distance at which high-temperature water rises through the casing pipe remain the same, but the casing pipe Pipe inner tube and cold water layer A
Since the heat insulating layer is interposed between the casing pipe and the cold water layer, the heat conductivity of the casing pipe to the cold water layer is significantly reduced, and the heat conductivity of the conventional casing pipe can be reduced to 1/10.

Therefore, the temperature drop that occurs before the hot water in the high-temperature water layer reaches the ground can be reduced to 1/1O.

For example, if a high-temperature water layer of 40 degrees is 30 degrees when it reaches the ground, it becomes 39 degrees by applying the present invention.

[Example] An embodiment will be described with reference to FIG.

An outer tube 4 having a diameter of 200 mm is buried to a depth that penetrates the rock C, and an inner tube l' is inserted into the outer tube 4. The inner pipe 1' is similar to the casing pipe in the prior art, and its lower end reaches the high temperature water layer C.

An annular gap having a thickness of 25 mm is formed between the inner tube l' and the outer tube 4, and this gap is filled with a non-water-absorbing heat insulating material 5 such as foamed resin.

The high-temperature water in the inner pipe l' is lifted to the ground via the hot water pump 3 by the submersible pump 2. The high-temperature water in the high-temperature water layer rises several hundred meters inside the inner pipe l', but since the inner pipe 1' and the cold water layer A are insulated by the heat insulating layer formed by the heat insulating material 5, the inner pipe l' There is little heat dissipation while ascending several hundred meters, and therefore the temperature drop during this period is small.
is a slit.

[Effects] The above-mentioned problem of the present invention is a novel problem that has not yet been solved. Therefore, the fact that this problem is solved and the problems of the prior art described above are eliminated is itself an effect unique to the present invention.

For deep hot springs, the pumped water temperature can be raised by nearly 10 degrees, which brings about the following advantages.

First, the reheating temperature can be significantly reduced.

In the case of large power, the heating facility can be significantly downsized.

Therefore, installation, operation and management costs can be greatly reduced. Depending on the water temperature of the high-temperature hot water layer, it may be possible to eliminate the need for reheating for products that conventionally required reheating.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional deep hot spring well, and FIG. 2 is a sectional view of an embodiment of the present invention. In the figure, 1...casing pipe, 1'...inner pipe,
2... Submersible pump, 3... Hot water pipe, 4... Outer pipe,
5...Insulation material, A...Cold water layer, B...Bedrock, C.
...is a high-temperature water layer.

Claims (1)

[Claims] Regarding deep hot spring wells, a hot water pump is inserted into the casing pipe and a submersible pump is attached to the lower end of the hot water pipe.
A hot water pumping facility for preventing a drop in the temperature of pumped water, in which the casing pipe is a hollow double insulated pipe, and the heat insulating layer of the insulated pipe has a length that reaches the bedrock layer.