JPH09242037A - Ground heating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make even ground heating and ensure low cost operation by making heated fluid flowing in a metal tube layed under the ground, and using both energy of heated fluid and electricity through flow of current to the pipe itself, or using one of them independently. SOLUTION: Between a pair of metal tube 2 for a header disposed in parallel, a plurality of metal pipes 3 thinner than these pipes 2 are connected in parallel and layed underground in the piping condition. To the metal pipe for header 2 heated fluid circulation path 4 in which heated fluid of water from a well via an insulation joint 5. Between the pipes 2 an AC current power supply 13 is connected and current is supplied to the pipes 2, 3 to heat them. Through the supply of current to the metal pipes 2, 3 themselves and flow of heated fluid into the metal piping 1 both energy of elctricity and heated fluid can be applicable. Accordingly selectable changeover operation is carried out according to the condition of energy to thereby reducing the operation cost to relatively low.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground heating system which can be used as a snow melting device for roads, parking lots, playgrounds, runways, etc., or as a heating device for growing natural grass in winter such as soccer fields. It is a thing.

[0002]

2. Description of the Related Art Conventionally, as a ground heating system used as a snow melting device or a heating device, an electric heater is buried under the ground and electricity is supplied to the electric heater to utilize its heat generation. Heating type, or buried pipe under the ground, hot water obtained by boiler or heat pump, hot water of hot spring, hot water obtained by using waste heat,
Alternatively, a heating fluid system in which well water or the like pumped by a well is made to flow and the heat thereof is utilized can be used.

However, conventional ground heating systems are either electrically heated or heated fluid,
Consider the energy situation of the area when installing,
The reality is that one of them is selected and installed, but once installed, it cannot be easily switched because the energy situation has changed. However, there was a problem that the usable energy source was restricted.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a ground heating system capable of selectively switching between electric power or heating fluid, or in some cases both energy sources, depending on the situation. To provide. Another object of the present invention is a system capable of selectively using both energies of electric or heating fluids, but at the same time the initial cost required for installation can be suppressed to be substantially equal to that of a single-use system of electricity or heating fluids. To provide a heating system.

[0005]

In order to solve the above-mentioned problems, the ground heating system according to the present invention lays an electrically conductive metal tube covered with an insulating material under the ground and circulates a heating fluid in the metal tube. While connecting the heating fluid circulation system to
It is characterized by being connected to an AC power supply that causes an electric current to flow through the metal pipe to heat the metal pipe itself.Because the metal pipe is laid under the ground, a heating fluid is allowed to flow inside the metal pipe. Either as a heating fluid method, or as an electric heating method by passing an electric current through the metal tube itself,
Alternatively, they can be used in combination, and can be selectively used depending on the energy situation.

Further, the ground heating system according to the present invention is
In the above system, the metal pipe is laid by connecting a number of metal pipes in parallel between a pair of metal pipes for headers arranged at predetermined intervals. By laying the metal pipe in this way, the entire ground can be heated almost uniformly.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.
It will be described based on. FIG. 1 is a configuration diagram of a ground heating system according to an embodiment of the present invention. Reference numeral 1 is a conductive metal tube made of copper, iron or the like, which is laid under the specified ground for snow melting or heating, and which is insulated and coated.

The metal tube 1 is composed of a pair of header metal tubes 2 which are arranged in parallel at a set interval as shown in the figure, and a number of thinner metal tubes 3 are connected in parallel. Then, it is laid under the ground in the state of being piped. A heating fluid circulation system passage 4 for circulating a heating fluid such as hot water or well water is connected to the pair of header metal tubes 2 via an insulating joint 5.

The heating fluid circulation system path 4 forms a closed circuit, and a pump 6 for fluid circulation and a heat exchange device 7 for heating the heating fluid are installed in the circuit. The heat exchange device 7 includes a heating fluid and an oil or gas-fired boiler 8
The heating fluid supplied to the metal tube 1 can be heated by exchanging heat with the hot water obtained in step 1 and circulated by the pump 9.

On the other hand, an AC power source 1 is provided between a pair of header metal tubes 2 via an electric cable 10 and terminals 11.
2 is connected, and an electric current is passed through the metal tubes 2 and 3 to generate heat. Since the heating fluid circulation system passage 4 is connected to the metal pipe 2 for the header through the insulating joint 5, even if an electric current is applied to the metal pipes 2 and 3, the heating fluid circulation system passage 4 is leaked. There is nothing to come.

However, according to the above-described embodiment, the metal tubes 2 and 3 can be heated by causing a current to flow from the AC power source 12 to the metal tubes 2 and 3 through the terminal 11 and the electric cable 10. , The heat can heat the ground. In addition, hot water is produced in the boiler 8 and is circulated to the heat exchange device 7 via the pump 9,
The heating fluid is heated by exchanging heat with the heating fluid (warm water) in the heating fluid circulation path 4 circulated by the heating fluid, and the heating fluid is supplied from the metal pipe 2 for one header, and the large number of metal pipes 3 Through the metal pipe 2 for the other header,
During this time, the ground can be heated by the heat of the heating fluid.

As described above, by using the metal tubes 2 and 3 and passing an electric current through the metal tubes themselves, or by flowing a heating fluid in the metal tubes, energy of both electric and heating fluids can be generated in one system. Can be used. Here, in order to uniformly heat the whole ground by flowing electricity or heating fluid through the metal pipes 2 and 3 laid under the ground,
It is important how the metal pipes 2 and 3 are laid, and by adopting the header system as described above, the electric pipe or the metal pipe 3 for the header is used to flow the electricity or the heating fluid uniformly. Therefore, uniform heating can be realized as a whole.

Therefore, according to the above system, heating operation can be performed at night by using relatively inexpensive nighttime electric power, and in the daytime, the oil or gas fired boiler 8 is used and the heating fluid heated thereby is used. It can be operated by heating, or in some circumstances, it can be operated by using energy of both electricity and heated fluid. Therefore, the switching operation can be selectively performed according to the energy situation, and
This makes it possible to keep operating costs relatively low.

Further, since the metal pipes 2 and 3 through which the heating fluid flows are also used as electric heaters, this system is installed at an initial cost which is almost equal to that of a system using normal hot water or well water. can do. In the above embodiment, the system for obtaining the heating fluid (warm water) by the boiler 8 has been described. However, the hot water from the hot spring, the waste hot water discharged from the factory, or the hot water obtained by utilizing the waste heat is directly heated as the heating fluid. It is needless to say that the system can be used as a heating source for supplying the circulating fluid to the circulation passage 4 for circulation or for heating the heating fluid via the heat exchange device 7.

It is also possible to construct a system in which a well is provided as the heating fluid and well water pumped from the well is used. Also in this case, the well water may be directly supplied to the heating fluid circulation system passage 4 and circulated in the metal tubes 2 and 3.

[0016]

As described above, according to the ground heating system of the present invention, since the metal pipe is laid under the ground, the heating fluid is made to flow through the metal pipe, and the metal heating pipe is used. Any one of the electric heating methods can be used alone or in combination by passing an electric current through the tube itself. Therefore, it is possible to selectively switch and use according to the energy status, and at the same time, it is possible to realize low cost operation by switching and using. Also,
Since the metal pipe through which the heating fluid flows is also used as the electric heater, it can be installed at an initial cost almost equal to that of a system using normal hot water or well water. Furthermore, since the metal pipe is laid by connecting many metal pipes in parallel between a pair of metal pipes for headers arranged at a predetermined interval,
Electricity or heating fluid can be evenly flowed from the header metal tube to a large number of metal tubes, and the entire ground can be heated almost uniformly.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a ground heating system according to an embodiment of the present invention.

[Explanation of symbols]

1 Metal Pipe 2 Metal Pipe for Header 3 Many Metal Pipes 4 Heated Fluid Circulation System 5 Insulation Joint 6, 9 Pump 7 Heat Exchanger 8 Boiler 10 Electric Cable 11 Terminal 12 AC Power Supply

Claims (2)

[Claims] 1. A conductive metal tube covered with insulation is laid below the ground, and a heating fluid circulation system passage for circulating a heating fluid is connected to the metal tube, and an electric current is passed through the metal tube to supply the same metal. A ground heating system characterized by being connected to an AC power source that heats the tube itself. 2. The metal pipe is laid by connecting a number of metal pipes in parallel between a pair of metal pipes for headers arranged at a predetermined interval. Ground heating system.