JP6393372B2 - Refrigerant system with direct contact heat exchanger - Google Patents

Description

  The present invention relates to a refrigerant system including a direct contact heat exchanger that directly contacts two refrigerants.

Currently, equipment that uses heat pump cycles (refrigeration cycles), such as air conditioners and refrigerators, uses HFC (hydrofluorocarbon) refrigerants typified by R410A, but regulations to prevent global warming Against the backdrop of strengthening, the development of refrigerants with low GWP (Global-warming potential) is underway.
In addition to global warming, various refrigerants are being developed in consideration of safety such as cycle efficiency (performance) and nonflammability.

On the other hand, a refrigerant system such as a general air conditioner to which a refrigerant is applied has been developed on the extension of the conventional configuration.
That is, it uses an HFC refrigerant and includes a compressor, an outdoor heat exchanger, an expansion valve, an indoor heat exchanger, and the like.

By the way, if it says that GWP is low, it is preferable to use natural refrigerants, such as carbon dioxide, propane, and water, which exist in nature.
In Patent Document 1, carbon dioxide and water, which are natural refrigerants, are used, and a heat pump cycle is constituted by carbon dioxide, and the cold heat of carbon dioxide is transmitted to water and conveyed. Carbon dioxide and water are mixed in the heat exchange tank. As a result, water and carbon dioxide come into direct contact, and the cold heat of carbon dioxide is transmitted to the water. Then, the carbon dioxide is transferred to a separator and separated from water, and then returned to the heat pump cycle.

JP-A-11-351684

When two refrigerants are brought into direct contact as in Patent Document 1, heat exchange is possible without having a temperature difference between the two as in the case of using a general indirect contact heat exchanger such as a fin-and-tube type. is there. Then, it is not necessary to lower the refrigerant temperature to an excessively low temperature in order to perform heat exchange. Since the input to the compressor can be reduced correspondingly, the efficiency (performance) of the heat pump cycle is high.
Here, it is difficult to introduce the high-temperature / high-pressure hydrocarbon refrigerant discharged from the compressor of the heat pump cycle directly into the contact heat exchanger and use the heat transferred from the hydrocarbon refrigerant to water for heating. This is because it is often difficult to ensure a sufficient density difference to sufficiently separate the hydrocarbon refrigerant and water depending on the pressure conditions in the heat exchanger. When the hydrocarbon refrigerant containing a large amount of water flows through the heat pump cycle, the heat pump cycle is not established.
Moreover, it is difficult to completely separate water and hydrocarbon refrigerant by any method. For this reason, when the outside air is at or near freezing temperature, there is a risk that the moisture mixed in the refrigerant freezes. Therefore, a functional product in the heat pump cycle, such as an expansion valve, becomes a failure factor. In that case, the heat pump cycle is not established when heating is used.

  Accordingly, the present invention provides a heat-usable refrigerant system including a heat exchanger that directly contacts a first refrigerant flowing through a heat pump cycle and a second refrigerant that receives heat from the first refrigerant and is conveyed to a heat load. The purpose is to do.

The refrigerant system of the present invention includes a compressor that compresses the first refrigerant, a first heat exchanger that performs heat exchange between the first refrigerant and the heat source, and a decompression unit that depressurizes the pressure of the first refrigerant. Heat pump cycle, a second heat exchanger that exchanges heat between the second refrigerant and the heat load, a heat transfer cycle that includes a pump that pumps the second refrigerant, the first refrigerant, and the first refrigerant Two direct contact heat exchangers that directly contact the refrigerant, an indirect contact heat exchanger that indirectly contacts the liquid in the direct contact heat exchanger and the first refrigerant, and a direction switching unit that switches a direction in which the first refrigerant flows. A heat exchanger switching unit that switches the flow of the first refrigerant to one of a direct contact heat exchanger and an indirect contact heat exchanger, and the liquid stored in the direct contact heat exchanger The first refrigerant inlet located below the First coolant, characterized in that the flow into the liquid to.
In addition, another refrigerant system of the present invention includes a compressor that compresses the first refrigerant, a first heat exchanger that performs heat exchange between the first refrigerant and the heat source, and a decompression unit that depressurizes the pressure of the first refrigerant. A heat pump cycle configured to include a second heat exchanger that performs heat exchange between the second refrigerant and the heat load, and a heat transfer cycle configured to include a pump that pumps the second refrigerant, The direct contact heat exchanger that directly contacts the first refrigerant and the second refrigerant, the indirect contact heat exchanger that indirectly contacts the liquid and the first refrigerant in the direct contact heat exchanger, and the flow direction of the first refrigerant are switched. A direction switching unit, and a heat exchanger switching unit that switches the flow of the first refrigerant to one of a direct contact heat exchanger and an indirect contact heat exchanger, and the inside of the direct contact heat exchanger includes the first refrigerant A mixing chamber in which the second refrigerant and the second refrigerant are mixed; And a second refrigerant, characterized in that it is divided into a separation chamber being separated.

In such a refrigerant system, as a result of switching by the direction switching unit, when the first low-temperature / low-pressure refrigerant flows directly from the decompression unit toward the contact heat exchanger, the cold heat of the first refrigerant is transmitted to the second refrigerant for cooling. Use.
When using cooling, a direct contact heat exchanger is used by the heat exchanger switching unit. If it does so, while being able to mix a 1st refrigerant | coolant and a 2nd refrigerant | coolant with a direct contact heat exchanger and performing heat exchange with high efficiency, a 1st refrigerant | coolant and a 2nd refrigerant | coolant can be isolate | separated based on a density difference.

On the other hand, at the time of heating, the direction switching unit switches the direction of the flow of the first refrigerant so that the high-temperature and high-pressure first refrigerant discharged from the compressor flows directly toward the contact heat exchanger. When using heating, an indirect contact heat exchanger is used by the heat exchanger switching unit.
Here, since the 1st refrigerant | coolant which flows through an indirect contact heat exchanger and the liquid inside a direct contact heat exchanger contact indirectly through the tube of an indirect contact heat exchanger, they are not mixed.
Therefore, even if the high temperature and high pressure first refrigerant flowing in from the compressor makes it difficult for the direct contact heat exchanger to sufficiently separate the first refrigerant and the second refrigerant, the first refrigerant and Since the second refrigerant is not mixed, there is no possibility that the second refrigerant is mixed into the first refrigerant.
Moreover, since the 1st heat exchanger functions as an evaporator at the time of heating utilization, the surrounding air of a 1st heat exchanger will be 0 degrees or less, and if the 2nd refrigerant | coolant freezes inside a 1st heat exchanger, it will cause a failure. However, since the second refrigerant is not mixed into the first refrigerant, there is no possibility of failure due to freezing.
Therefore, since the concern about the separation of the first refrigerant and the second refrigerant at the time of heating utilization and icing can be eliminated, a refrigerant system for cooling and heating that can enjoy a high heat exchange rate by a direct contact heat exchanger is provided. Can do.

In the refrigerant system of the present invention, it is preferable that the first refrigerant flows into the liquid through the first refrigerant inlet located below the liquid level of the liquid to be stored inside the direct contact heat exchanger.
This configuration contributes particularly to the promotion of mixing of the first refrigerant and the second refrigerant during heating.

When the gas-liquid two-phase first refrigerant flows into the mixing chamber from the first refrigerant inlet, the gas of the first refrigerant is diffused while floating in the liquid of the stored second refrigerant. In the process, the gas of the first refrigerant and the second refrigerant mix and come into direct contact sufficiently. Here, since the first refrigerant inflow port is located below the liquid level of the liquid stored in the direct contact heat exchanger, the gas of the first refrigerant rises and diffuses upward, and the second refrigerant and The contact area can be made wider than the liquid level or when the first refrigerant inlet is located above the liquid level. For this reason, the first refrigerant and the second refrigerant can be brought into sufficient contact.
On the other hand, the liquid of the first refrigerant is also mixed with the liquid of the second refrigerant in the direct contact heat exchanger, thereby sufficiently contacting the second refrigerant. Similarly to the above, the first refrigerant gasified by the heat exchange at that time is also diffused in the second refrigerant, and is sufficiently in direct contact with the second refrigerant.
Since the high heat exchange efficiency by making the 1st refrigerant and the 2nd refrigerant contact directly by the above can fully be acquired, the efficiency of a heat pump cycle can be improved.

  The second refrigerant to which the heat of the first refrigerant has been transferred by direct contact with the first refrigerant is taken out of the direct contact heat exchanger and conveyed to a heat load, etc., and is used for heat utilization. The second refrigerant conveyed to the heat load can be returned directly to the inside of the contact heat exchanger.

  In the refrigerant system of the present invention, the direct contact heat exchanger is divided into a mixing chamber in which the first refrigerant and the second refrigerant are mixed and a separation chamber in which the first refrigerant and the second refrigerant are separated. Is preferred.

Both the first refrigerant and the second refrigerant flow into the mixing chamber, and heat exchange is performed when the first refrigerant and the second refrigerant are sufficiently in contact with each other in the mixing chamber. Thereafter, the first refrigerant and the second refrigerant in the mixing chamber flow into the separation chamber and are separated.
The gas of the first refrigerant flows out from the gas reservoir space located above the liquid level in the mixing chamber and the separation chamber to the heat pump cycle. The second refrigerant flows out from the separation chamber to the heat transfer cycle.

Here, the separation chamber is separated from the flow associated with the floating, diffusion, and evaporation of the first refrigerant in the mixing chamber by a wall body or the like. Therefore, the liquid that has flowed into the separation chamber from the mixing chamber can be left in a stationary state and easily separated based on the density difference.
On the other hand, since the mixing chamber is separated from the separation chamber by a wall body or the like, the first refrigerant flowing into the mixing chamber from the first refrigerant inlet is immediately from the outlet of the second refrigerant in the separation chamber. It does not go out and is sufficiently mixed with the water refrigerant in the mixing chamber.

In the refrigerant system of the present invention, in the mixing chamber, the first refrigerant flows into the liquid in the mixing chamber via the first refrigerant inlet located below the liquid level of the stored liquid, and the mixing chamber and the separation chamber Is preferably communicated above the first refrigerant inflow port.
Since the mixing chamber and the separation chamber communicate with each other above the first refrigerant inlet, it floats and diffuses from the first refrigerant inlet in the mixing chamber, so that it is slower than the flow around the first refrigerant inlet. The resulting liquid is poured into the separation chamber. For this reason, it is possible to suppress the influence of the flow in the mixing chamber on the separation of the first refrigerant and the second refrigerant in the separation chamber as much as possible, and to sufficiently separate the first refrigerant and the second refrigerant based on the density difference.

In the present invention, the refrigerant system is configured as an air conditioner, the second heat exchanger is installed indoors, a path through which the second refrigerant flows from the direct contact heat exchanger to the second heat exchanger, and a second The path through which the second refrigerant flows from the heat exchanger to the direct contact heat exchanger passes through the room, and the second refrigerant is preferably water.
According to the said structure, water flows in the piping provided in the room | chamber of a heat transfer cycle, and the 2nd heat exchanger.
If it does so, even if the 1st refrigerant | coolant in a direct contact heat exchanger flows into the heat conveyance cycle, it can block | prevent that combustion of a 1st refrigerant | coolant generate | occur | produces indoors with water.
Therefore, the risk of combustion in the room can be suppressed regardless of the combustibility of the first refrigerant.
In addition, by using water with a significantly low GWP (0) as the second refrigerant, the GWP of the refrigerant system determined according to the ratio of the amount of the first refrigerant and the second refrigerant enclosed can be reduced.

  According to the present invention, there is provided a heat-usable refrigerant system including a heat exchanger that directly contacts a first refrigerant flowing through a heat pump cycle and a second refrigerant that receives heat from the first refrigerant and is conveyed to a heat load. can do.

It is a figure which shows the structure of the refrigerant | coolant system for heating which concerns on the reference example of this invention. It is a graph which shows the relationship between temperature and a liquid density in the saturated aqueous solution of a HSC refrigerant | coolant. It is a figure which shows the structure of the cooling / heating combined refrigerant system which concerns on embodiment of this invention (at the time of air_conditionaing | cooling operation). It is a figure which shows the structure of the refrigerant | coolant system for cooling / heating which concerns on embodiment of this invention (at the time of heating operation). It is a figure which shows the structure of the refrigerant | coolant system combined with the air_conditioning | cooling / heating which concerns on the modification of this invention (at the time of air_conditionaing | cooling operation). It is a figure which shows typically the internal structure of the direct contact heat exchanger with which the modification of this invention is provided.

First, after describing a configuration of a reference example that can solve a problem common to the present invention, embodiments (FIGS. 3 and 4) of the present invention will be described with reference to some components from the reference example.
[Reference example]
The refrigerant system 1 shown in FIG. 1 includes a heat source cycle 40 (heat pump cycle) in which a first refrigerant circulates, a heat transfer cycle 20 in which a second refrigerant circulates, and direct contact heat that directly contacts the first refrigerant and the second refrigerant. An exchanger 50 and a separator 55 that separates the first refrigerant and the second medium depressurized and transferred from the direct contact heat exchanger 50 are provided.
The whole refrigerant system 1 is a closed cycle sealed with respect to the atmosphere.

As the first refrigerant and the second refrigerant, those having extremely different boiling points are used. The boiling point of the second refrigerant is higher than that of the first refrigerant.
In the present reference example, R1234ze, which is a kind of HFO (Hydro Fluoro Olefin) refrigerant, is used as the first refrigerant, and the first refrigerant is referred to as a heat source cycle side refrigerant (hereinafter referred to as Heat Source Cycle, HSC refrigerant). Here, in addition to R1234ze, HSC refrigerants such as HFO refrigerant R1234yf and HFC refrigerant R32 can also be suitably used as the first refrigerant.
On the other hand, water is used as the second refrigerant, and the second refrigerant is referred to as a water refrigerant.
Under atmospheric pressure, R1234ze has a boiling point of about −19 ° C. and water has a boiling point of 100 ° C.

The refrigerant system 1 is configured as an air conditioner that is operated for heating in order to heat indoor air as a heat load using outside air as a heat source, and includes an outdoor unit 1A and an indoor unit 1B.
The outdoor unit 1A includes a compressor 11, a first heat exchanger 12, a first blower 13, a decompression unit 14, a pump 23, and a direct contact heat exchanger 50 described below.
The indoor unit 1B includes a second heat exchanger 21 described below.

The equipment configuration of the refrigerant system 1 is not limited to this reference example, and can be arbitrarily configured according to the installation space of the equipment.
The outdoor unit 1A and the indoor unit 1B included in the refrigerant system 1 include the components of the heat source cycle 40, the components of the heat transfer cycle 20, and the direct contact heat exchanger 50 in consideration of the allowable device housing size and the like. Are appropriately arranged.
The components of each cycle 40, 20 and the direct contact heat exchanger 50 do not necessarily have to be housed in the casing of the outdoor unit 1A or the indoor unit 1B.
For example, the pump 23 is attached to piping constituting the circuit of the heat transfer cycle 20 between the direct contact heat exchanger 50 arranged in the outdoor unit 1A and the second heat exchanger 21 of the indoor unit 1B. ing. The pump 23 may be disposed in the outdoor unit 1A. Further, the present invention allows the pump 23 to be disposed in the indoor unit 1B.

Hereinafter, each structure of the heat source cycle 40, the heat transfer cycle 20, the direct contact heat exchanger 50, and the separator 55 will be described in order.
[Heat source cycle]
The heat source cycle 40 includes a compressor 11 that compresses HSC refrigerant, a first heat exchanger 12 that performs heat exchange between the HSC refrigerant and outside air, a first blower 13 that blows air toward the first heat exchanger 12, and A pressure reducing unit 14 for reducing the pressure of the HSC refrigerant is provided.
The HSC refrigerant circulates through the heat source cycle 40 via the direct contact heat exchanger 50 and the separator 55 by a heat pump action accompanying a change in the pressure and temperature of the HSC refrigerant.

  The heat source cycle 40 is operated in such a direction that the high-temperature and high-pressure HSC refrigerant compressed by the compressor 11 flows directly into the contact heat exchanger 50.

The compressor 11 compresses and discharges the HSC refrigerant sucked into the housing by a scroll compression mechanism or a rotary compression mechanism.
It is preferable to determine the displacement of the compressor 11 according to the volume capacity of the HSC refrigerant used.

The first heat exchanger 12 includes a tube through which the HSC refrigerant flows and fins provided on the tube. The first heat exchanger 12 performs heat exchange indirectly between the HSC refrigerant and the outside air via the tubes and fins. The first heat exchanger 12 functions as an evaporator in this reference example.
It is preferable that the 1st heat exchanger 12 is set to the size which considered the pressure loss according to the volume capacity of the HSC refrigerant | coolant used.
The first blower 13 is a propeller fan or the like, and promotes heat exchange by the first heat exchanger 12.

The decompression unit 14 decompresses the HSC refrigerant.
As the decompression unit 14, an expansion valve that controls the flow rate of the refrigerant while also injecting the refrigerant in a mist can be preferably used. Further, a capillary tube that depressurizes the refrigerant by a throttling action can also be used as the decompression unit 14.

[Heat transfer cycle]
Next, the heat transfer cycle 20 includes a second heat exchanger 21 that performs heat exchange between the water refrigerant and room air, a second blower 22 that blows air toward the second heat exchanger 21, and water refrigerant. And a circulating pump 23.
The water refrigerant is circulated through the heat transfer cycle 20 via the direct contact heat exchanger 50 and the separator 55 by being pumped by the pump 23.

The second heat exchanger 21 has a tube through which water refrigerant flows and fins provided on the tube. The second heat exchanger 21 performs heat exchange indirectly between the water refrigerant and the room air via the tubes and fins. The second heat exchanger 21 functions as a water refrigerant condenser.
The second blower 22 is a propeller fan or the like, and promotes heat exchange by the second heat exchanger 21.

The pump 23 has a necessary capacity according to the flow rate of the water refrigerant corresponding to the heat load.
As the pump 23, any type of pump such as a positive displacement type or a non-displacement type can be used.
The pump 23 of this reference example includes a direct current (DC) motor that is driven with low power consumption, and is a DC pump that can control the rotation speed. By adopting such a DC pump, power input necessary for the operation of the refrigerant system 1 can be suppressed, which can contribute to improving the efficiency of the refrigerant system 1.

[Direct contact heat exchanger]
Next, the direct contact heat exchanger 50 mixes the HSC refrigerant and the water refrigerant and directly exchanges heat.
The capacity of the direct contact heat exchanger 50 is determined in consideration of the heat capacity to be given to the water refrigerant stored inside. The height of the inside of the direct contact heat exchanger 50 is determined in consideration of the liquid level at which the stored water refrigerant liquid and the HSC refrigerant can be sufficiently mixed.
The liquid stored in the direct contact heat exchanger 50 may include an HSC refrigerant liquid.
In the direct contact heat exchanger 50, the upper part of the liquid level of the stored liquid is a gas storage space 37 in which the gas of the HSC refrigerant is stored.

The direct contact heat exchanger 50 performs heat exchange by mixing the high-pressure and high-temperature HSC refrigerant discharged from the compressor 11 of the heat source cycle 40 and the water refrigerant flowing in from the heat transfer cycle 20.
The direct contact heat exchanger 50 takes out and separates an HSC inlet 501 for injecting HSC refrigerant from the heat source cycle 40, a water inlet 502 for injecting water refrigerant from the heat transfer cycle 20, and a mixed refrigerant of HSC refrigerant and water refrigerant. And a transfer outlet 503 for transferring to the container 55.

HSC inlet 501 is an opening located at the end of the pipe H _IN drawn from above the direct contact heat exchanger 50.
Water inlet 502 is an opening located at the end of the pipe W _IN drawn from the side in direct contact heat exchanger 50.
The transfer outlet 503 is an opening located at the end of the transfer path 45. Via the transfer outlet 503, the mixed liquid of the water refrigerant and the HSC refrigerant in the direct contact heat exchanger 50 is taken out.

Each of the piping H _IN , the piping W _IN , and the transfer path 45 is arbitrarily arranged. The same applies to the pipe H _OUT and the pipe W _OUT described later.
The HSC inlet 501 and the water inlet 502 are preferably positioned and oriented so that the HSC refrigerant and the water refrigerant are sufficiently mixed.

The transfer outlet 503 is disposed below the liquid level in the direct contact heat exchanger 50. Thereby, the mixed liquid of the HSC refrigerant and the water refrigerant sufficiently mixed in the direct contact heat exchanger 50 is taken out from the transfer outlet 503 and transferred to the separator 55, so that the direct contact heat exchanger 50 directly Both heat exchange by contact and separation of the mixed refrigerant in the separator 55 are sufficiently performed.
If the transfer outlet 503 is disposed above the liquid level in the direct contact heat exchanger 50, the HSC refrigerant gas staying above the liquid level in the direct contact heat exchanger 50 is transferred. It flows out from the outlet 503. If it does so, neither heat exchange nor separation will fully be performed.
In order to prevent the HSC refrigerant flowing into the direct contact heat exchanger 50 from the HSC inlet 501 from immediately coming out of the transfer outlet 503, the transfer outlet 503 is sufficiently provided from both the HSC inlet 501 and the water inlet 502. It is preferable that they are separated from each other. Thereby, it can take out, after fully mixing the liquid mixture of a HSC refrigerant | coolant and a water refrigerant | coolant.

[Separator]
Next, the separator 55 separates the HSC refrigerant and the water refrigerant transferred from the direct contact heat exchanger 50.
The separator 55 is directly connected to the contact heat exchanger 50 through the transfer path 45.
The transfer path 45 is provided with a transfer-time pressure reducing unit 44 that reduces the pressure of the HSC refrigerant and the water refrigerant transferred from the direct contact heat exchanger 50 to the separator 55.
As the depressurizing unit 44 at the time of transfer, an expansion valve, a capillary tube, or the like can be used as in the depressurizing unit 14 of the heat source cycle 40.

  The separator 55 includes a transfer inlet 551 for taking in a mixed refrigerant of HSC refrigerant and water refrigerant from the direct contact heat exchanger 50 via the transfer path 45, and a water outlet for letting the water refrigerant flow out to the heat transfer cycle 20. 552 and an HSC outlet 553 through which the gas of the HSC refrigerant flows out to the heat source cycle 40.

The transfer inlet 551 is an opening located at the end of the transfer path 45.
The transfer inlet 551 is disposed below the liquid level in the separator 55.
If the transfer inlet 551 is disposed above the liquid level in the separator 55, the mixed liquid of the HSC refrigerant and the water refrigerant taken into the separator 55 from the transfer inlet 551 is The HSC outlet 553 located above the liquid level in the separator 55 may directly flow out. If it does so, since a water refrigerant | coolant mixes in the heat source cycle 40, it will lead to the efficiency fall and malfunction of a heat pump cycle.
The liquid mixture taken into the separator 55 from the transfer inlet 551 is left in a stationary state, and is separated into HSC refrigerant gas, water refrigerant (liquid), and HSC refrigerant liquid based on the density difference between them. Is done.

  A resistance plate that provides resistance to the flow of the mixed liquid flowing out from the transfer inlet 551 is provided in the vicinity of the transfer inlet 551, or the transfer inlet 551 is opposed to the bottom of the separator 55 (see FIG. 1). It is preferable to prevent the flow of the mixed solution flowing into the separator 55 from affecting the separation of the mixed solution in the separator 55 as much as possible.

The water outlet 552 is an opening located at the end of the pipe W _OUT through which the water refrigerant flows out.
The water outlet 552 is preferably sufficiently spaced from the transfer inlet 551 and disposed in the lower part of the separator 55. In this reference example, the water outlet 552 is located at the lower end of the pipe W _OUT that is drawn from the side into the separator 55 and bent downward, and opens toward the bottom 311.

The HSC outlet 553 is an opening located at the end of the pipe H _OUT that allows the gas of the HSC refrigerant to flow out to the heat source cycle 40.
The HSC outlet 553 is disposed in the gas reservoir space 37 above the liquid level in the separator 55. The HSC outlet 553 is preferably arranged at the upper part of the gas reservoir space 37.

In the refrigerant system 1 configured as described above, high-temperature and high-pressure HSC refrigerant flows directly into the contact heat exchanger 50 in order to perform heating operation. And the water refrigerant in which the heat | fever of the high temperature / high pressure HSC refrigerant | coolant was transferred is conveyed in the direct contact heat exchanger 50, and the air of a conveyance destination is heated.
Here, since the direct contact heat exchanger 50 has a high temperature and a high pressure, the HSC refrigerant liquid and the water refrigerant exist as saturated aqueous solutions in the direct contact heat exchanger 50.

  FIG. 2 shows the relationship between temperature and liquid density in a saturated aqueous solution of HSC refrigerant. The liquid density (solid line) of the water refrigerant hardly changes between the temperature range T1 during the cooling operation and the temperature range T2 during the heating operation when the temperature in the direct contact heat exchanger 50 is. On the other hand, the liquid density (broken line) of the HSC refrigerant is larger than the liquid density of the water refrigerant in the temperature range T1, but decreases as the temperature rises and eventually falls below the liquid density of the water refrigerant.

In the temperature range T2 during the heating operation, since the difference in liquid density between the water refrigerant and the HSC refrigerant is small, it is difficult to sufficiently separate the water refrigerant and the HSC refrigerant.
Therefore, in this reference example, the saturated aqueous solution of the HSC refrigerant is taken out from the direct contact heat exchanger 50 and depressurized by the depressurizing unit 44 at the time of transfer. Thereby, the mixed refrigerant on the saturated liquid line is taken into the two-phase region and transferred to the separator 55 for separation.

The operation of the direct contact heat exchanger 50 and the separator 55 in this reference example will be described.
When the HSC refrigerant flows into the direct contact heat exchanger 50 from the HSC inlet 501, the HSC refrigerant is diffused in the stored liquid. In the process, the HSC refrigerant and the water refrigerant come in direct contact with each other to transfer heat. In the direct contact heat exchanger 50, the HSC refrigerant and the water refrigerant are sufficiently mixed to become a saturated aqueous solution.

  The saturated aqueous solution of the HSC refrigerant in the direct contact heat exchanger 50 is taken out from the transfer outlet 503 to the transfer path 45 and decompressed by the decompression unit 44 during transfer. A saturated aqueous solution of HSC refrigerant is taken into the two-phase region by decompression.

The HSC refrigerant and the water refrigerant depressurized by the depressurizing unit 44 at the time of transfer flow into the separator 55 from the transfer intake 551 as a gas-liquid two-phase flow.
In the separator 55, the HSC refrigerant and the water refrigerant are sufficiently separated into the HSC refrigerant liquid, the water refrigerant, and the HSC refrigerant gas based on the density difference.

The gas of the HSC refrigerant separated from the water refrigerant is accumulated in the gas reservoir space 37. Then, the HSC refrigerant gas in the gas reservoir space 37 is returned to the heat source cycle 40 from the HSC outlet 553.
Since the HSC outlet 553 of this reference example is located at the uppermost part in the gas reservoir space 37, the gas of the HSC refrigerant flowing out from the HSC outlet 553 contains water refrigerant only up to the saturated water vapor pressure level.
On the other hand, the water refrigerant in the separator 55 separated from the HSC refrigerant gas flows out of the water outlet 552 and is conveyed by the heat conveyance cycle 20. At this time, the liquid of the HSC refrigerant may flow out from the water outlet 552 to the heat transfer cycle 20 together with the water refrigerant. Even if the HSC refrigerant flows through the heat transfer cycle 20, combustion of the HSC refrigerant is prevented by the water flowing together.

As described above, even if it is difficult to ensure a sufficient density difference to sufficiently separate the HSC refrigerant and the water refrigerant due to the pressure conditions in the direct contact heat exchanger 50, the present reference example is a separator. In 55, the HSC refrigerant and the water refrigerant can be sufficiently separated.
In particular, during heating operation, if the HSC refrigerant and the water refrigerant are present as a saturated aqueous solution in the direct contact heat exchanger 50, and the water refrigerant and the HSC refrigerant are mixed as they are, the heat pump cycle is entered. Does not hold. However, since the HSC refrigerant from which the water refrigerant has been sufficiently removed can be returned to the heat source cycle 40 by using the depressurization unit 44 and the separator 55 during transfer as in this reference example, the heat pump cycle can be maintained.
Therefore, the refrigerant system 1 for heating that can enjoy a high heat exchange rate by the direct contact heat exchanger 50 can be provided.

Further, in the refrigerant system 1 that uses both the HSC refrigerant and the water refrigerant, the GWP is determined according to the ratio of the amount enclosed in the refrigerant system 1.
The GWP of the HSC refrigerant is 4 to 2300. On the other hand, the GWP of the water refrigerant is zero. By using a water refrigerant with an extremely low GWP and an HSC refrigerant in combination, a very low GWP of about “5” can be realized.

Furthermore, even if the HSC refrigerant flows into the heat transfer cycle 20 due to the flow of water refrigerant in the pipes provided in the room of the heat transfer cycle 20 and in the second heat exchanger 21, the combustion of the HSC refrigerant in the room. Can be prevented by water.
Therefore, the risk of combustion in the room can be suppressed regardless of the combustibility of the HSC refrigerant.

By the way, in the refrigerant system 1 of the present reference example, a cooling / heating machine can be configured by appropriately adding and branching pipes and providing a switching valve for switching the direction of the flow of the HSC refrigerant in the heat source cycle 40. it can.
The cooling / heating combined machine has the significance of establishing a heat pump cycle under pressure conditions during heating operation, and also during cooling operation, the HSC refrigerant from which water refrigerant has been sufficiently removed is returned to the heat pump cycle, Reduction in cycle efficiency and occurrence of defects can be prevented in advance.

Embodiment
Next, an embodiment of the present invention will be described.
The refrigerant system 2 of the embodiment shown in FIGS. 3 and 4 is used as an air conditioner capable of both a cooling operation and a heating operation.
Hereinafter, the same components as those described in the above reference example are denoted by the same reference numerals, and description thereof is omitted or simplified.

The refrigerant system 2 includes a heat source cycle 60 in which an HSC refrigerant is circulated as a first refrigerant, a heat transfer cycle 20 in which a water refrigerant is circulated as a second refrigerant, and a direct contact heat exchanger that directly contacts the HSC refrigerant and the water refrigerant. 61, an indirect contact heat exchanger 62 that indirectly contacts the liquid in the direct contact heat exchanger 61 and the HSC refrigerant, a four-way switching valve 65 that switches the direction in which the HSC refrigerant flows in the heat source cycle 60, and the flow of the HSC refrigerant Is provided with heat exchanger switching valves 66 and 67 for switching to any one of the direct contact heat exchanger 61 and the indirect contact heat exchanger 62.
The refrigerant system 2 is a closed cycle sealed with respect to the atmosphere.

Hereinafter, each structure of the direct contact heat exchanger 61 and the indirect contact heat exchanger 62 is demonstrated in order.
[Direct contact heat exchanger]
The direct contact heat exchanger 61 stores the flowing water refrigerant and HSC refrigerant.
During the cooling operation (FIG. 3), heat exchange is performed when the HSC refrigerant and the water refrigerant are in direct contact in the direct contact heat exchanger 61. During the cooling operation, the HSC refrigerant flows into the direct contact heat exchanger 61 from the heat source cycle 60, and the HSC refrigerant in the direct contact heat exchanger 61 is returned to the heat source cycle 60.

  The direct contact heat exchanger 61 includes an HSC inlet 611 through which HSC refrigerant flows, a water inlet 612 through which water refrigerant flows, an HSC outlet 613 through which HSC refrigerant flows out, and a water outlet 614 through which water refrigerant flows out. Have.

HSC inlet 611 is an opening located at the end of the pipe _{H IN} drawn into direct contact heat exchanger 61.
Water inlet 612 is an opening located at the end of the pipe W _IN drawn into direct contact heat exchanger 61.
The handling of the pipe H _IN and the pipe W _IN is arbitrary. The same applies to the pipe H _OUT and the pipe W _OUT described later.
The HSC inlet 611 and the water inlet 612 are preferably positioned and oriented so that the HSC refrigerant and the water refrigerant are sufficiently mixed.

The HSC outlet 613 is an opening located at the end of the pipe H _OUT that allows the gas of the HSC refrigerant to flow out to the heat source cycle 60.
The HSC outlet 613 is disposed in the gas reservoir space 37 above the liquid level in the direct contact heat exchanger 61. The HSC outlet 613 is preferably disposed in the upper part of the gas reservoir space 37.
The water outlet 614 is an opening located at the end of the pipe W _OUT through which the water refrigerant flows out.

[Indirect contact heat exchanger]
Next, the indirect contact heat exchanger 62 includes a tube 621 through which the HSC refrigerant flows and fins (not shown) that are thermally connected to the tube 621. The indirect contact heat exchanger 62 is schematically shown.
The indirect contact heat exchanger 62 passes below the liquid level of the liquid stored in the direct contact heat exchanger 61, and the HSC refrigerant flowing in the tube 621 and the liquid in the direct contact heat exchanger 61 Heat exchange indirectly.

The direct contact heat exchanger 61 and the indirect contact heat exchanger 62 configured as described above are connected to the heat source cycle 60 in parallel.
These direct contact heat exchanger 61 and indirect contact heat exchanger 62 are selectively used by switching the heat exchanger switching valves 66 and 67.

[Operation during cooling operation]
The operation of the refrigerant system 2 during the cooling operation will be described with reference to FIG.
During the cooling operation, the direction of the HSC refrigerant flow in the heat source cycle 60 is switched by the four-way switching valve 65 so that the HSC refrigerant flows directly from the decompression unit 14 into the contact heat exchanger 61.
In addition, the flow of the HSC refrigerant to the indirect contact heat exchanger 62 is blocked by the heat exchanger switching valves 66 and 67, thereby switching the flow of the HSC refrigerant to the direct contact heat exchanger 61.
If it does so, the HSC refrigerant | coolant which flowed in in the direct contact heat exchanger 61 will mix with the water refrigerant | coolant stored in the direct contact heat exchanger 61, and will contact directly. Thereby, the cold energy transferred from the HSC refrigerant to the water refrigerant is conveyed, and the air at the conveyance destination is cooled.
The mixed HSC refrigerant and water refrigerant are left stationary in the direct contact heat exchanger 61, and are separated into HSC refrigerant gas, water refrigerant (liquid), and HSC refrigerant liquid based on the density difference between them. The

[Operation during heating operation]
The operation of the refrigerant system 2 during heating operation will be described with reference to FIG.
During the heating operation, the four-way switching valve 65 switches the direction of the HSC refrigerant flow so that the HSC refrigerant discharged from the compressor 11 flows directly into the contact heat exchanger 61.
In addition, the flow of the HSC refrigerant to the direct contact heat exchanger 61 is blocked by the heat exchanger switching valves 66 and 67, thereby switching the flow of the HSC refrigerant to the indirect contact heat exchanger 62.
Then, the HSC refrigerant flowing in the tube 621 of the indirect contact heat exchanger 62 comes into indirect contact with the liquid in the direct contact heat exchanger 61. Thereby, the heat transferred from the HSC refrigerant to the water refrigerant is conveyed, and the air at the conveyance destination is heated.
Since the HSC refrigerant in the tube 621 of the indirect contact heat exchanger 62 and the liquid in the direct contact heat exchanger 61 are isolated by the tube 621, they are not mixed.
Therefore, even if the pressure condition in which the direct contact heat exchanger 61 is difficult to sufficiently separate the HSC refrigerant and the water refrigerant by the high-temperature and high-pressure HSC refrigerant flowing from the compressor 11 during the heating operation, Since the refrigerant and the water refrigerant are not mixed, there is no possibility that the water refrigerant is mixed into the HSC refrigerant.

  Moreover, since the 1st heat exchanger 12 functions as an evaporator at the time of heating operation, if the surrounding air of the 1st heat exchanger 12 becomes 0 degree | times or less and water refrigerant freezes in the 1st heat exchanger 12, it will be a cause of failure. However, since no water refrigerant is mixed into the HSC refrigerant, there is no risk of failure due to freezing.

  According to the present embodiment, since the direct contact heat exchanger 61 and the indirect contact heat exchanger 62 are used in combination as described above, the concern regarding the separation of the HSC refrigerant and the water refrigerant and the freezing during the heating operation can be eliminated. The cooling / heating refrigerant system 2 that can enjoy a high heat exchange rate by the direct contact heat exchanger 61 can be provided.

[Modification of the present invention]
The configuration of the direct contact heat exchanger included in the refrigerant system of the present invention is not limited to the form of the direct contact heat exchanger shown in each of the above embodiments.
The refrigerant system 3 according to the modification of the present invention shown in FIG. 5 is replaced with the direct contact heat exchanger 61 of the above embodiment, except that a direct contact heat exchanger 63 is provided. Configured in the same way.
The direct contact heat exchanger 63 can also be applied to the above reference example.

  The direct contact heat exchanger 63 liquefies the HSC refrigerant via the HSC inlet 351 located below the liquid level of the liquid to be stored so that the HSC refrigerant and the water refrigerant are more sufficiently mixed especially during the cooling operation. It is divided into a mixing chamber 35 and a separation chamber 36, and the mixing chamber 35 and the separation chamber 36 communicate with each other above the HSC inlet 351.

As shown in FIG. 6, the direct contact heat exchanger 63 includes a tank 31, a partition wall 32 that partitions the inside of the tank 31, and a resistance plate 33 that is installed in the lower portion of the tank 31.
The tank 31 is formed in a cylindrical shape, and includes a bottom 311, a peripheral wall 312 that rises from the periphery of the bottom 311, and a lid 313 that closes an opening of the peripheral wall 312.
The capacity of the tank 31 is determined in consideration of the heat capacity that the water refrigerant stored in the tank 31 wants to have. The height of the inside of the tank 31 is determined in consideration of the liquid level at which the liquid of the stored water refrigerant and the HSC refrigerant can be sufficiently mixed, and sufficient separation of the mixed HSC refrigerant and water refrigerant. .
Since the gas-liquid two-phase HTC refrigerant flows into the tank 31, the HSC refrigerant liquid is also stored in the tank 31 in addition to the water refrigerant (liquid). Therefore, the “liquid level” means a liquid level obtained by combining the liquids of the water refrigerant and the HSC refrigerant.

The partition wall 32 is erected on the bottom 311. The inside of the tank 31 is divided into a mixing chamber 35 located on one side of the dividing wall 32 and a separation chamber 36 located on the other side of the dividing wall 32.
The partition wall 32 has a width corresponding to the inner diameter of the tank 31 and is formed at a height higher than a predetermined reference liquid level L in the tank 31 and lower than the height inside the tank 31.
A plurality of communication holes 320 penetrating in the thickness direction are formed in a predetermined region on the upper end 32 </ b> A side of the partition wall 32. These communication holes 320 allow the mixing chamber 35 and the separation chamber 36 to communicate with each other. Among these, one or more communication holes 320 are located above the HSC inlet 351 described later.
One or more communication holes 320 among the plurality of communication holes 320 are positioned below the reference liquid level L. For this reason, the passage of liquid between the mixing chamber 35 and the separation chamber 36 is allowed through the communication hole 320.
The space between the liquid level stored in the mixing chamber 35 and the separation chamber 36 and the lid 313 is a gas reservoir space 37 in which the gas of the HSC refrigerant is accumulated.

  The resistance plate 33 provided in the mixing chamber 35 serves as a resistance against the flow of the HSC refrigerant flowing into the mixing chamber 35. The resistance plate 33 protrudes horizontally from the partition wall 32. A flow path for the HSC refrigerant is ensured between the tip of the resistance plate 33 and the peripheral wall 312.

Hereinafter, the mixing chamber 35, the separation chamber 36, and the gas reservoir space 37 will be described.
[Mixing chamber]
The mixing chamber 35 exchanges heat by mixing the HSC refrigerant that has flowed in through the pressure reducing unit 14 of the heat source cycle 40 and the water refrigerant that has flowed in from the heat transfer cycle 20. When the cold heat of the HSC refrigerant is transferred to the water refrigerant by heat exchange, the HSC refrigerant evaporates (gasifies).
The mixing chamber 35, the HSC inlet 351 is an opening of the pipe _{H IN} for flowing HSC refrigerant, a water inlet 352 is an opening of the pipe _{W IN} flowing a coolant-refrigerant is disposed.

The HSC inlet 351 is located in the lower part in the tank 31. Specifically, HSC inlet 351 is located at the upper end of the pipe _{H IN} drawn from below the tank 31 into the mixing chamber 35 is opened upward at the bottom 311 of the tank 31. The position of the HSC inflow port 351 may be above the bottom 311, but is defined below the liquid level of the liquid stored in the tank 31.
The HSC inflow port 351 faces the lower surface of the resistor plate 33 described above.

Water inlet 352 is located at the lower end of the pipe W _IN which is drawn from above the tank 31 into the mixing chamber 35 extends downward.
The water inflow port 352 opens downward near the resistance plate 33 and the peripheral wall 312.

The piping H _IN and the piping W _IN are arbitrarily arranged.
For example, it is also possible to draw the mixing chamber 35 the pipe H _IN from the side or above the tank 31. However, the pipe _HIN is provided so that the HSC inlet 351 is positioned below the liquid level of the stored liquid so that the HSC refrigerant and the water refrigerant are sufficiently mixed.
It is also possible to draw the mixing chamber 35 the pipe W _IN from the side or below the tank 31.
Piping _{H IN} and the pipe _{W IN,} it is preferable that the flow from each of the HSC inlet 351 and water inlet 352 is provided so as to merge the different orientations.

The indirect contact heat exchanger 62 is provided so as to pass through the liquid in the mixing chamber 35.
However, the indirect contact heat exchanger 62 can also be provided so as to pass through the liquid in the separation chamber 36.

[Separation room]
Next, the separation chamber 36 separates the HSC refrigerant and the water refrigerant that have undergone heat exchange by being mixed with each other. By returning the gas of the HSC refrigerant separated from the water refrigerant to the heat source cycle 40, it is possible to prevent deterioration in cycle efficiency, breakage, and generation of rust due to the water refrigerant entering the heat source cycle 40.
The liquid flowing into the separation chamber 36 from the mixing chamber 35 is separated into the HSC refrigerant gas, the water refrigerant (liquid), and the HSC refrigerant liquid based on the density difference in the separation chamber 36.

In the separation chamber 36, a water outlet 362 that is an opening of a pipe W _OUT through which water refrigerant flows out is disposed.
The water outlet 362 is preferably disposed in the lower part of the separation chamber 36. The water outlet 362 of the present embodiment is located at the lower end of the pipe W _OUT drawn into the separation chamber 36 from the side of the tank 31 and bent downward, and opens toward the bottom 311.
The piping W _OUT is arbitrarily arranged. For example, the pipe W _OUT can be drawn into the separation chamber 36 from below the tank 31.

The separation chamber 36 is separated by the partition wall 32 from the flow accompanying the floating, diffusion, and evaporation of the HSC refrigerant in the mixing chamber 35. Therefore, the liquid that has flowed into the separation chamber 36 from the mixing chamber 35 can be left in a stationary state and easily separated based on the density difference.
On the other hand, since the mixing chamber 35 is separated from the separation chamber 36 by the partition wall 32, the HSC refrigerant that has flowed into the mixing chamber 35 from the HSC inlet 351 is placed in the lower part of the tank 31 as in the HSC inlet 351. It does not immediately exit from the water outlet 362 located, and is sufficiently mixed with the water refrigerant in the mixing chamber 35.

[Gas reservoir space]
In the gas reservoir space 37, an HSC outlet 371 that is an opening of a pipe _HOUT through which the gas of the HSC refrigerant flows out to the heat source cycle 40 is disposed.
It is preferable that the HSC outlet 371 is arranged at the upper part in the gas reservoir space 37.
HSC outlet 371 is located at the lower end of the pipe _{H OUT} drawn from above the tank 31 to the gas reservoir space 37, which opens downward.
The HSC outlet 371 is sufficiently separated from the reference liquid level L in the tank 31.
The piping H _OUT is arbitrarily arranged. For example, the pipe H _OUT can be drawn into the gas storage space 37 from the side of the tank 31.

The effect | action by the direct contact heat exchanger 63 comprised as mentioned above is demonstrated.
During the cooling operation, a gas-liquid two-phase HSC refrigerant flows upward into the mixing chamber 35 from the HSC inlet 351 located in the lower portion of the mixing chamber 35. The gas of the HSC refrigerant is diffused while floating in the liquid stored in the mixing chamber 35. In the process, the gas of the HSC refrigerant and the water refrigerant are mixed and sufficiently in direct contact with each other. Part of the gas of the HSC refrigerant leaves the liquid level and accumulates in the gas reservoir space 37.
On the other hand, the liquid of the HSC refrigerant is mixed with the water refrigerant in the mixing chamber 35 so that it is in direct contact with the water refrigerant. As a result, the gasified HSC refrigerant is sufficiently in direct contact with the water refrigerant while being diffused in the liquid.

Here, since the HSC inlet 351 is located in the lower part of the tank 31, the region where the gas of the HSC refrigerant rises and diffuses upward and comes into contact with the water refrigerant is located in the upper part of the tank 31. It can be taken wider than the case where it is located. Therefore, the water refrigerant and the HSC refrigerant can be sufficiently brought into contact with each other, and the cold heat of the HSC refrigerant can be sufficiently transferred to the water refrigerant.
Further, the flow of the HSC refrigerant flowing from the HSC inlet 351 causes a pressure loss by the resistance plate 33 provided facing the HSC inlet 351. For this reason, the HSC refrigerant can be more fully brought into contact with the water refrigerant while slowly flowing upward.

  Further, the water refrigerant flowing in from the water inlet 352 is joined from above with the flow of the HSC refrigerant passing between the resistance plate 33 and the peripheral wall 312. Due to the stirring action thus obtained, the water refrigerant and the HSC refrigerant can be brought into sufficient contact.

As described above, heat exchange is performed when the HSC refrigerant and the water refrigerant are mixed and sufficiently contacted in the mixing chamber 35. In the mixing chamber 35, a liquid in which water refrigerant and HSC refrigerant are mixed is stored, and the gas of the HSC refrigerant is melted in the liquid mixture.
The liquid in the mixing chamber 35 is moved to the separation chamber 36, and in the separation chamber 36, the gas of the HSC refrigerant, the water refrigerant, and the liquid of the HSC refrigerant are separated by a mutual density difference.

  Here, the mixing chamber 35 and the separation chamber 36 are connected to each other of the mixing chamber 35 and the separation chamber 36 via a communication hole 320 formed in the partition wall 32 or, depending on the liquid level, the upper end 32A of the partition wall 32. Since the upper part communicates with the upper part, the liquid which has floated and diffused from the HSC inlet 351 in the mixing chamber 35 and has become slower than the flow around the HSC inlet 351 is poured into the separation chamber 36. For this reason, it is suppressed as much as possible that the flow in the mixing chamber 35 affects the separation of the HSC refrigerant and the water refrigerant in the separation chamber 36, and the liquid of the HSC refrigerant, the water refrigerant, and the gas of the HSC refrigerant are mutually exchanged based on the density difference. Can be sufficiently separated.

The gas of the HSC refrigerant separated from the water refrigerant is accumulated in the gas reservoir space 37. Then, the HSC refrigerant gas in the gas reservoir space 37 is returned from the HSC outlet 371 to the heat source cycle 40.
Since the HSC outlet 371 of the present embodiment is located at the uppermost part in the gas reservoir space 37, the gas of the HSC refrigerant flowing out from the HSC outlet 371 contains water refrigerant only up to the saturated water vapor pressure level.

  On the other hand, the water refrigerant in the separation chamber 36 separated from the gas of the HSC refrigerant flows out of the water outlet 362 and is transferred by the heat transfer cycle 20. At this time, the HSC refrigerant liquid may flow from the water outlet 362 to the heat transfer cycle 20 together with the water refrigerant. Even if the HSC refrigerant flows through the heat transfer cycle 20, combustion of the HSC refrigerant is prevented by the water flowing together.

  According to the refrigerant system 3 of the present example, as described above, the HSC refrigerant is allowed to flow into the lower part of the mixing chamber 35 of the direct contact heat exchanger 63 via the HSC inlet 351, particularly during the cooling operation. Thus, the water refrigerant and the HSC refrigerant can be sufficiently brought into contact with each other over a wide area from the lower part to the upper part in the mixing chamber 35. For this reason, since the heat exchange effect by direct contact is fully exhibited, the refrigerant system 3 as a whole can achieve high efficiency.

  Further, the inside of the tank 31 of the direct contact heat exchanger 63 is divided into the mixing chamber 35 and the separation chamber 36 by the dividing wall 32, and then the mixing chamber is connected via the communication hole 320 of the dividing wall 32 or the upper end 32 A of the dividing wall 32. 35 and the separation chamber 36 communicate with each other at the top, so that the liquid in the separation chamber 36 can be kept as stationary as possible. Thereby, the HSC refrigerant and the water refrigerant can be sufficiently separated based on the density difference.

During the heating operation, as described with reference to FIG. 4 in the above embodiment, the HSC refrigerant is discharged so that the HSC refrigerant discharged from the compressor 11 directly flows into the contact heat exchanger 61 by the four-way switching valve 65. Switch the flow direction.
In addition, the flow of the HSC refrigerant to the direct contact heat exchanger 61 is blocked by the heat exchanger switching valves 66 and 67, thereby switching the flow of the HSC refrigerant to the indirect contact heat exchanger 62.
Then, the HSC refrigerant flowing in the tube 621 of the indirect contact heat exchanger 62 comes into indirect contact with the liquid in the direct contact heat exchanger 61. Thereby, the heat transferred from the HSC refrigerant to the water refrigerant is conveyed, and the air at the conveyance destination is heated.
Since the HSC refrigerant in the tube 621 of the indirect contact heat exchanger 62 and the liquid in the direct contact heat exchanger 61 are isolated by the tube 621 and are not mixed, there is a possibility that water refrigerant is mixed into the HSC refrigerant. Absent.

In the direct contact heat exchanger 63 described above, the HSC refrigerant and the water refrigerant are mixed when the HSC inlet 351 is positioned below the liquid level even though the mixing chamber 35 and the separation chamber 36 are not divided. Is promoted.
Further, in the direct contact heat exchanger 63 described above, even if the HSC inlet 351 is equal to or above the liquid level, the HSC refrigerant and the water refrigerant are separated by the mixing chamber 35 and the separation chamber 36. Is promoted.

In addition to the above, as long as the gist of the present invention is not deviated, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.
The equipment configuration of the refrigerant system of the present invention is arbitrary, and may include, for example, a plurality of indoor units 1B to which water refrigerant cooled by heat exchange in the direct contact heat exchangers 50 and 61 is distributed. In that case, it is economically preferable to dispose one pump 23 having a capacity that can be distributed to each indoor unit 1B outside the indoor unit 1B.
As the first refrigerant and the second refrigerant in the present invention, any refrigerant having extremely different boiling points, that is, a non-azeotropic refrigerant can be used. For example, the first refrigerant is propane, the second refrigerant is a water refrigerant, the first refrigerant is carbon dioxide, the second refrigerant is a water refrigerant, the first refrigerant is ammonia, and the second refrigerant is a water refrigerant. it can.
Further, the second refrigerant is not limited to the water refrigerant, and for example, the use of brine is also permitted. Examples of the brine include those having ethylene glycol or propylene glycol as the main component.
And the direct contact heat exchanger and refrigerant | coolant system of this invention can also be applied not only to an air conditioner but to a freezer, a water heater, a chiller, etc.

1 to 3 Refrigerant system 1A Outdoor unit 1B Indoor unit 11 Compressor 12 First heat exchanger 13 First blower 14 Depressurization unit 20 Heat transfer cycle 21 Second heat exchanger 22 Second blower 23 Pump 31 Tank 32 Partition wall 32A Upper end 33 Resistance plate 35 Mixing chamber 36 Separation chamber 37 Gas reservoir space 40 Heat source cycle (heat pump cycle)
44 Depressurization unit 45 during transfer 45 Transfer path 50 Direct contact heat exchanger 55 Separator 60 Heat source cycle (heat pump cycle)
61 Direct Contact Heat Exchanger 62 Indirect Contact Heat Exchanger 63 Direct Contact Heat Exchanger 65 Four-way Switching Valve (Direction Switching Unit)
66,67 Heat exchanger switching valve (heat exchanger switching section)
311 Bottom 312 Perimeter wall 313 Lid 320 Communication hole 351 HSC inlet 352 Water inlet 362 Water outlet 371 HSC outlet 501 HSC inlet 502 Water inlet 503 Transfer outlet 551 Transfer inlet 552 Water outlet 553 HSC outlet 611 HSC inlet 612 Water inlet 613 HSC outlet 614 Water outlet 621 Tube H _IN piping H _OUT piping L Reference liquid level T1 Temperature range T2 Temperature range W _IN piping W _OUT piping

Claims (4)

A heat pump cycle that includes a compressor that compresses the first refrigerant, a first heat exchanger that exchanges heat between the first refrigerant and a heat source, and a decompression unit that depressurizes the pressure of the first refrigerant; ,
A second heat exchanger that exchanges heat between the second refrigerant and the heat load, and a heat transfer cycle that includes a pump that pumps the second refrigerant;
A direct contact heat exchanger that directly contacts the first refrigerant and the second refrigerant;
An indirect contact heat exchanger that indirectly contacts the liquid in the direct contact heat exchanger and the first refrigerant;
A direction switching unit that switches a direction in which the first refrigerant flows;
A heat exchanger switching unit that switches the flow of the first refrigerant to one of the direct contact heat exchanger and the indirect contact heat exchanger ,
Inside the direct contact heat exchanger,
The first refrigerant flows into the liquid via the first refrigerant inlet located below the liquid level of the stored liquid;
A refrigerant system characterized by that. A heat pump cycle that includes a compressor that compresses the first refrigerant, a first heat exchanger that exchanges heat between the first refrigerant and a heat source, and a decompression unit that depressurizes the pressure of the first refrigerant; ,
A second heat exchanger that exchanges heat between the second refrigerant and the heat load, and a heat transfer cycle that includes a pump that pumps the second refrigerant;
A direct contact heat exchanger that directly contacts the first refrigerant and the second refrigerant;
An indirect contact heat exchanger that indirectly contacts the liquid in the direct contact heat exchanger and the first refrigerant;
A direction switching unit that switches a direction in which the first refrigerant flows;
A heat exchanger switching unit that switches the flow of the first refrigerant to one of the direct contact heat exchanger and the indirect contact heat exchanger ,
In the direct contact heat exchanger,
A mixing chamber in which the first refrigerant and the second refrigerant are mixed;
A separation chamber in which the first refrigerant and the second refrigerant are separated;
A refrigerant system characterized by that. In the mixing chamber, the first refrigerant flows into the liquid through the first refrigerant inlet located below the liquid level of the stored liquid,
The mixing chamber and the separation chamber communicate with each other above the first refrigerant inlet.
The refrigerant system according to claim 2 . Configured as an air conditioner,
The second heat exchanger is installed indoors,
A path through which the second refrigerant flows from the direct contact heat exchanger to the second heat exchanger and a path through which the second refrigerant flows from the second heat exchanger to the direct contact heat exchanger pass through the room. ,
The second refrigerant is water.
The refrigerant system according to any one of claims 1 to 3 .

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