JP2958614B2 - Heat medium circulation unit for underground heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat medium circulating unit for an underground heat exchanger that collects abundant geothermal heat throughout the four seasons for air conditioning, hot water supply, hot water pool, plant cultivation, animal breeding, snow melting, etc. It is.

[0002]

[0009] The present invention is not currently used to extract groundwater, which is a low-level heat source, and use it for air conditioning, hot water supply, heated pools, plant cultivation, animal breeding, snow melting, and the like. The reason is that pumping groundwater causes land subsidence.

Further, a method of burying a heat exchanger for extracting geothermal heat underground, sending a heat medium to the heat exchanger, and indirectly exchanging the heat with the heat medium via a heat transfer surface to collect geothermal heat. However, there are few methods that are suitable for geothermal characteristics and are an excellent means for efficiently extracting geothermal heat.

[0004] The present invention provides a heat medium circulation unit for an underground heat exchanger capable of efficiently extracting geothermal heat.

[0005]

A description will be given with reference to the drawings. The heat medium circulating unit for an underground heat exchanger according to the present invention sends the heat medium M downward by one of the concentric double tubes 1 for heat exchange in which the inner tube 1b is concentrically inserted into the outer tube 1a. When the geothermal heat received by inverting and guiding the inside of the other pipe upward is sent to a plurality of sets of radiating pipes 9b and used for snow melting, etc., a plurality of concentric double pipes and a plurality of sets of radiating pipes 9b are used. And two heat medium circulation pumps 2, one of which is used as a spare, provided in the heat medium circulation path 3 for circulating the heat medium M between the heat medium M and the heat medium M. An expansion tank 4 for absorbing a change in volume is provided, and a pressure switch 5 for stopping the operation of the pump 2 when a pressure lower than a set pressure lower limit value due to leakage of the heat medium M or the like is detected.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, reference numeral 1 denotes a concentric double tube for heat exchange buried vertically in the ground to collect geothermal heat, which is concentric with an outer tube receiving the geothermal heat. If multiple tubes are installed at the same location with the inner tube inserted,
In order to avoid mutual thermal interference, they need to be separated by at least 5 m.

The concentric double tube for heat exchange 1 will be described in more detail.
The heat medium M made of the antifreeze liquid is sent downward, turned upside down, guided upward between the outer pipe and the inner pipe, and sent to the heat radiating portion 9 such as snow melting on the road. The outer tube (diameter 9)
0 mm) and the inner tube (56 mm) are both made of hard polyethylene.

Reference numeral 2 denotes a heat medium supply pump, and one heat medium supply pump is provided for four to six concentric double tubes 1 except for the spare (one of the two heat medium supply pumps is spare). Reference numeral 3 denotes a heat medium circulation path for circulating the heat medium M, 3a denotes a main pipe of a feed pipe, 3b denotes a main pipe of a return pipe, 3d denotes a flow meter, and 3e denotes an automatic air vent valve.

In addition, 4 is an expansion tank which communicates with the heat medium circulation path 3 and absorbs a change in volume of the heat medium M, 4a is a pressure gauge,
Reference numeral 4b denotes a relief valve, 4c denotes an automatic air release valve, and 5 denotes a pressure switch, which stops the operation of the pump 2 when a pressure lower than a set pressure lower limit value due to a leak of the heat medium M or the like is detected. 9 is a heating medium M sent from a plurality of concentric double tubes 1
And a heat dissipating unit that melts snow or the like through a plurality of heat dissipating tubes 9b connected to three headers 9a.

In operation, when one of the heat medium circulating pumps 2 is driven, the heat medium M is distributed to the concentric double pipes 1 through the feed pipe main pipe 3a of the heat medium circulating path 3 and is concentric with each other. It is sent downward by the inner pipe of the double pipe 1, turned upside down, and heated by receiving geothermal heat while being guided upward in the outer pipe.
The heat medium M that has exited each concentric double pipe 1 passes through the heat medium circulation path 3,
After being sent to the radiator 9 and distributed to a plurality of headers 9a, further distributed to a plurality of radiator tubes 9b at each header 9a, and used for melting snow, etc., the heat medium circulating pump 2 passes through the main tube 3a through the main tube 3a. It is returned to the concentric double tube 1.

In the meantime, the heating medium M is controlled so as to flow 20 to 25 liters / minute per concentric double tube, and when the volume of the heating medium M changes due to a temperature change, the volume change is absorbed by the expansion tank 4. You. Further, when a pressure lower than the set pressure lower limit value due to the leakage of the heat medium M or the like is detected, the pressure switch 5 is operated, and the operation of the pump 2 is stopped.

[0012]

Since the present invention is configured as described above, the configuration of the unit can be simply and compactly housed, the pump 2 can also be used with a low output, the operating cost can be reduced, It is extremely useful because it is suitable for use in snow melting, heating, hot water supply, etc., with less failures and lower maintenance costs.

[Brief description of the drawings]

FIG. 1 is a device configuration diagram showing an embodiment of the present invention.

FIG. 2 is a device configuration diagram showing a main part of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Concentric double pipe 1a Outer pipe 1b Inner pipe 2 Pump 3 Heat medium circulation path 3a Feed pipe main pipe 3b Return pipe main pipe 3d Flow meter 3e Automatic air release valve 4 Expansion tank 4a Pressure gauge 4b Release valve 4c Automatic air release valve 5 Pressure switch 9 Heat radiating section 9a Header 9b Heat radiating pipe M Heat medium

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F24J 3/08

Claims (1)

(57) [Claims] 1. A heat medium (M) is fed downward by one of heat-exchanging concentric double tubes (1) in which an inner tube (1b) is inserted concentrically into an outer tube (1a) and then inverted. Then, the geothermal heat received by leading the inside of the other pipe upward is sent to a plurality of sets of radiating pipes (9b) and used for snow melting and the like, and a plurality of concentric double pipes and a plurality of sets of radiating pipes are used. Between the heat medium circulation path (3) for circulating the heat medium, and using one as a spare 2
An expansion tank (4) provided with a base heat medium circulation pump (2, 2) and connected to a heat medium circulation path to absorb a change in volume of the heat medium.
And a pressure switch (5) for stopping operation of the pump when a pressure lower than a set pressure lower limit value due to leakage of the heat medium or the like is detected.