JPH07167523A - Heating tower type heat pump - Google Patents

Abstract

PURPOSE:To prevent mixture of brine with fresh water by eliminating the necessity of a valve operation on the brine side at the time of switching according to season. CONSTITUTION:The heating tower type heat pump comprises a compressor 1, a first heat exchanger 21, a second heat exchanger, and a unit for alternately switching the first and second exchangers 21, 22 with a condenser and an evaporator, wherein a brine coil 7 connected to a heating tower 5 is disposed in the exchanger 21, and a cold/warm water coil 18 supplied with fresh water is disposed in the exchanger 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating tower type heat pump used for district heating and cooling systems and the like.

[0002]

2. Description of the Related Art At present, a heating tower type heat pump is most widely used in the electric district heating and cooling system that does not use a boiler for producing hot water in winter. Figure 2
FIG. 1 is a configuration diagram showing a conventional heating tower type heat pump, in which a compressor 1, a condenser 2, an expansion valve 3 and an evaporator 4 are connected by a refrigerant pipe, and a heating tower 5 is arranged outside. There is. In the condenser 2, a hot water coil 6
And the cooling water coil 7 is provided, and the hot water coil 6
The pump 9 supplies fresh water to the brine coil 7
Can be connected to the heating tower 5 via a pump 10 and valves 12 and 13. A cold water coil (winter brine coil) 8 is provided in the evaporator 4,
The cold water coil 8 can be connected to the heating tower 5 via the pump 10 and the valves 14 and 15, and
Fresh water can be supplied through the pump 11 and the valves 16 and 17.

The operation of the heating tower type heat pump having the above structure will be described. The high-temperature and high-pressure refrigerant gas compressed by the compressor 1 is cooled and condensed by the condenser 2 and is decompressed by the expansion valve 3 to become a low-temperature and low-pressure refrigerant, which is evaporated by the evaporator 4 and returned to the compressor 1. Return. And
In the summer, as shown in FIG. 2 (A), the valve 1
2, 13, 16, 17 are opened, valves 14, 15 are closed, and brine (cooling water when the heating tower is a closed type or an open type) is circulated from the heating tower 5 to the cooling water coil 7 and condensed. Cooling the refrigerant in the vessel 2 and the heated brine are returned to the heating tower 5 to be cooled, and at the same time, the fresh water flowing in the hot water coil 6 is heated by the high temperature refrigerant in the condenser 2 to become hot water. Is supplied to. Further, in the evaporator 4, fresh water is supplied from the pump 11 to the cold water coil 8 and is cooled by the heat of evaporation of the refrigerant to become cold water, which is supplied to the user side.

On the other hand, in winter, as shown in FIG. 2B, the valves 14 and 15 are opened and the valves 12 and 1 are opened.
3, 16, 17 are closed, and the brine is circulated from the heating tower 5 to the cooling water coil 7 to take heat from the refrigerant in the evaporator 4, and the cooled brine returns to the heating tower 5 and heats the air and heat. The fresh water that is exchanged and heated and that flows through the hot water coil 6 in the condenser 2 is heated by the high-temperature refrigerant in the condenser 2 and becomes hot water to be supplied to the user side.

[0005]

However, in the above-mentioned conventional method, the summer fresh water and the winter brine are made to flow through the evaporator 4 of the heat pump, and the switching between the fresh water and the brine is performed by the switching operation of the valve. However, there is a problem that brine is mixed into fresh water in the summer due to incorrect operation of the valve or leak of the valve itself. Brine causes bacteria at low concentrations, causing clogging and corrosion of pipes. In district heating and cooling systems,
Since fresh water (cold water) is a product that is sent to customers, it is necessary to take the utmost care not to cause this problem.

The present invention solves the above-mentioned problems, and eliminates the need to operate a valve on the brine side at the time of switching seasons, thereby preventing the mixing of brine into fresh water by a heating tower heat pump. It is intended to provide.

[0007]

To this end, the heating tower heat pump of the present invention comprises a compressor 1, a first heat exchanger 21, a second heat exchanger 22, and first and second heat exchangers.
And a brine coil 7 connected to the heating tower 5 is disposed in the first heat exchanger 21. A cold / hot water coil 18 to which fresh water is supplied is arranged in the second heat exchanger 22. It should be noted that the numbers added to the above-mentioned configurations are for comparison with the drawings in order to facilitate the understanding of the present invention, and the configurations of the present invention are not limited thereby.

[0008]

In the present invention, for example, as shown in FIG.
The brine is circulated only in the first heat exchanger 21, and the refrigerant circuit is switched at the time of season switching, so that the first
Also, the roles of the condenser and the evaporator are exchanged in the second heat exchangers 21 and 22.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B are configuration diagrams showing an embodiment of a heating tower type heat pump of the present invention. FIG. 1A shows the operation in summer and FIG. 1B shows the operation in winter.

In FIG. 1, the compressor 1, the first heat exchanger 21, the expansion valves 3a and 3b, and the second heat exchanger 22 are connected by a refrigerant pipe, and the heating tower 5 is arranged outside. It is set up. Two bypass pipes 23 and 24 are connected between the discharge side and the suction side of the compressor 1, and
Discharge side, suction side and bypass pipes 23, 24 of the compressor 1
Are provided with switching valves V1, V2, V3 and V4. In addition, these switching valve and bypass pipe are the first and second
A switching device that alternately switches the heat exchangers 21 and 22 to a condenser and an evaporator, and a known four-way switching valve may be adopted instead of providing these switching valves and bypass pipes.
Further, when the compressor is a turbo, the expansion valve is unnecessary.

In the first heat exchanger 21, the hot water coil 6
Further, a brine coil 7 is provided, fresh water is supplied to the hot water coil 6 by a pump 9, and the brine coil 7 is connected to the heating tower 5 via a pump 10. A cold / hot water coil 18 is arranged in the second heat exchanger 22, and the cold / hot water coil 18 can supply fresh water via the pump 11.

The operation of the heating tower heat pump of the present invention having the above structure will be described.

First, in the summer, the switching valves V1, V4
Open and close the switching valves V2 and V3. As shown in FIG. 1 (A), the high-temperature high-pressure refrigerant gas compressed by the compressor 1 is
In the first heat exchanger 21, the brine is circulated from the heating tower 5 to the brine coil 7 (cooling water when the heating tower is a closed type and an open type), and the brine is heated. It is circulated to and cooled by exchanging heat with air. At the same time, the refrigerant gas is cooled by the fresh water flowing through the hot water coil 6, and the fresh water is heated by the high temperature refrigerant and becomes hot water to be supplied to the user side. The condensed refrigerant is decompressed by the expansion valve 3a to become a low-temperature low-pressure refrigerant and flows into the second heat exchanger 22, where the fresh water supplied from the pump 11 to the cold / hot water coil 8 is the heat of evaporation of the refrigerant. It is cooled by and becomes cold water and is supplied to the user side.

On the other hand, in winter, as shown in FIG. 1B, the switching valves V1 and V4 are closed and the switching valves V2 and V3 are opened. The high-temperature high-pressure refrigerant gas compressed by the compressor 1 is cooled by the fresh water supplied to the cold / hot water coil 8 in the second heat exchanger 21, and the fresh water is heated by the high-temperature refrigerant to become hot water, which is then used by the user. Supplied. The condensed refrigerant is
The refrigerant is decompressed by the expansion valve 3b to become a low-temperature low-pressure refrigerant, flows into the first heat exchanger 21, exchanges heat with the brine flowing through the brine coil 7, evaporates, and returns to the compressor. The refrigerant takes heat from the brine, and the cooled brine returns to the heating tower 5 and exchanges heat with the air to be heated.

[0015]

As is apparent from the above description, according to the present invention, the brine is circulated only in the first heat exchanger, and the refrigerant circuit is switched at the time of season switching,
By exchanging the roles of the condenser and the evaporator in the first and second heat exchangers, it is possible to prevent the operation of the valve on the brine side at the time of season switching, thereby preventing the mixture of brine into fresh water. it can.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a heating tower type heat pump of the present invention, FIG. 1 (A) shows an operation in summer and FIG. 1 (B) shows an operation in winter.

FIG. 2 is a configuration diagram showing an example of a conventional heating tower heat pump, and FIG. 2 (A) shows the operation in the summer.
(B) shows the operation in winter.

[Explanation of symbols]

1 ... Compressor, 3a, 3b ... Expansion valve, 5 ... Heating tower, 6 ... Hot water coil 7 ... Brine coil, 9, 10, 11 ... Pump, 18 ...
Cold / hot water coil 21 ... First heat exchanger, 22 ... Second heat exchanger

Claims (1)

[Claims] 1. A compressor, a first heat exchanger, a second heat exchanger, and a switching device for alternately switching the first and second heat exchangers to a condenser and an evaporator. A brine coil connected to the heating tower is arranged in the first heat exchanger, and a cold / hot water coil to which fresh water is supplied is arranged in the second heat exchanger. Ting tower heat pump.