JP2000337785A - Air-conditioning refrigerating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-conditioning refrigerating apparatus which can conduct storage and release of cold energy efficiently and also can conduct storage and radiation of heat, by using a medium producing a clathrate containing carbon dioxide or a hydrocarbon of a low cost, as a medium for storage of cold energy. SOLUTION: This apparatus is equipped with a primary refrigerating cycle having a compressor 2, a four-way valve 3, a first heat exchanger 4 and a restrictor 5 at least and with a cold energy and heat energy storage part 1 conducting storage of cold energy or storage of heat energy with carbon dioxide and water, or a hydrocarbon and water, used as a medium. The cold energy and heat energy storage part 1 is connected, in the storage of cold energy, so that the medium and the primary refrigerating cycle come into direct contact with each other for heat exchange, while it is connected to the primary refrigerating cycle, in the storage of heat energy, so that the medium and a refrigerant of the primary refrigerating cycle do not come into direct contact with each other and the heat exchange is conducted in a second heat exchanger 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioning refrigeration system.

[0002]

2. Description of the Related Art In recent years, a working medium in an air-conditioning refrigeration system has been changed from a conventional CFC refrigerant or HCFC refrigerant which has a harmful effect on the ozone layer to an HFC refrigerant or carbonized refrigerant which is a substitute refrigerant having no threat to the ozone layer. It is being transferred to hydrogen.

[0003] For example, the working medium for refrigerating includes a single refrigerant of R12 of CFC refrigerant, R134a of HFC refrigerant, R600a (isobutane) of hydrocarbon, RC270 (cyclopropane), and R290 (propane), and these. The transition to mixed refrigerants has been proposed.

The working medium for air conditioning is changed from R22 of HCFC refrigerant to R32, R125 and R134 of HFC refrigerant.
mixed refrigerant such as a, hydrocarbon R290 (propane),
Transition to a refrigerant mixture with R1270 (propylene) or R170 (ethane) has been proposed.

[0005] Here, the HFC refrigerant is non-flammable R125.
By selecting R134a or R134a, or by using a mixed refrigerant obtained by mixing nonflammable R125 or R134a with weakly flammable R32, there is an advantage that the possibility of ignition in the event of leakage of refrigerant can be reduced. However, they have the disadvantage that the global warming potential as a substance is large.

[0006] On the other hand, hydrocarbons have low global warming potential as substances, but R600a, RC270, R2
90, R1270, and R170 are all highly flammable, and the mixed refrigerant obtained by mixing them has the disadvantage of being highly flammable.

[0007] In addition, the ammonia refrigerant which has been conventionally used has almost no global warming potential as a substance, but has disadvantages in terms of toxicity, in addition to the disadvantage of weak flammability.

Therefore, in a future air conditioning refrigeration system,
It is important to realize a device configuration that contributes to the prevention of global warming and that can reduce the possibility of ignition in the event that a refrigerant leaks.

The use of an air conditioner for cooling during the summer season requires a large amount of energy mainly during the daytime. Therefore, an air conditioning refrigeration system that can use off-peak nighttime electric power is desired. An air-conditioning refrigeration apparatus that uses nighttime electric power performs air-conditioning refrigeration during the day by using a working medium frozen in a cold storage tank during off-peak hours at night. As an air-conditioning refrigeration apparatus corresponding to these, a secondary refrigeration cycle using another refrigerant such as water as a secondary refrigerant as shown in FIG.
A device configuration of a secondary refrigerant system that performs ice cold storage by exchanging heat without direct contact between the refrigerant of the secondary refrigeration cycle and the refrigerant of the secondary refrigeration cycle is generally used. In FIG. 4, reference numeral 21 denotes an ice regenerative tank filled with water acting as a refrigerant medium, and indirectly exchanges heat with the compressor 22, the condenser 23, the expansion device 24, and the water in the ice regenerator 21. An evaporator 25 and an accumulator 26 are connected by pipes, and HCFC 22 is generally sealed therein as a refrigerant. Further, cold storage energy stored as ice in the ice storage tank 21 is loaded into a load 2.
This is a well-known ice regenerative air-conditioning refrigeration system that constitutes a secondary refrigeration cycle 29 from a pump 28 circulating through a pump 7.

[0010]

However, the secondary refrigerant system includes a step of indirectly exchanging heat with the secondary refrigerant.
The compression energy of the compressor is increased as compared with the direct expansion system. Further, in ice cold storage, since the generation temperature is 0 ° C. or lower, it is necessary to further lower the evaporation temperature of the low-pressure section of the primary refrigeration cycle that generates cold heat, and the compression energy of the compressor increases. From this viewpoint, it has been difficult for the conventional secondary refrigerant system to contribute to the prevention of global warming.

In view of the above-mentioned problems, the present invention provides a clathrate (clathrate) containing water as a host solution and low-cost, non-toxic and low-cost carbon dioxide or hydrocarbon as a guest molecule. Another object of the present invention is to provide an air conditioning and refrigeration apparatus that can efficiently perform cold storage and cooling, and can also store and radiate heat by using a generation medium as a cooling medium.

[0012]

Means for Solving the Problems The first invention (claim 1)
Corresponds to the present invention described above) performs a primary refrigeration cycle having at least a compressor, a four-way valve, a first heat exchanger, and a throttling device, and performs cold storage or heat storage using carbon dioxide and water or hydrocarbons and water as a medium. A cold storage heat section, and the connection configuration between the cold storage heat section and the primary refrigeration cycle is such that the medium and the refrigerant of the primary refrigeration cycle come into direct contact with each other and exchange heat when storing cold, and when storing heat. The second medium is used without direct contact between the medium and the refrigerant of the primary refrigeration cycle.
An air conditioning refrigeration apparatus characterized in that heat is exchanged by a heat exchanger.

According to a second aspect of the present invention (corresponding to the second aspect of the present invention), the primary refrigeration cycle comprises an outlet line of the first heat exchanger acting as a condenser or an outlet of the second heat exchanger. A first air conditioning and refrigeration apparatus according to the present invention, further comprising a heat exchange means for exchanging heat between the side line and a suction line of the compressor.

According to a third aspect of the present invention (corresponding to the third aspect of the present invention), when the medium is carbon dioxide and water, the refrigerant of the primary refrigeration cycle is carbon dioxide, and the medium is hydrocarbon and water. In the case of (1), the refrigerant in the primary refrigeration cycle is a hydrocarbon.

According to a fourth aspect of the present invention (corresponding to the fourth aspect of the present invention), the temperature and the pressure of the medium in the cold storage heat section are kept below the specific temperature and the pressure which are the critical decomposition points of the clathrate of the medium during cold storage. And a control means for controlling a clathrate generation range sandwiched between a saturation pressure line of the medium and a clathrate generation limit line. It is.

[0016] Clathrate is defined as "a three-dimensional structure formed by bonding atoms or molecules has pores of an appropriate size, and another atom or molecule enters into the pores and a specific pore is formed. Substances that form a crystal structure. " The host solution is a substance that forms a skeleton of a three-dimensional structure, and generally uses water. The guest molecules fill the interior of the skeleton, stabilize the ice structure of the clathrate, and allow formation at temperatures much higher than the ice formation temperature (0 ° C.). The structure of the clathrate usually depends on the size of the guest molecule, and its formation and annihilation conditions (temperature, pressure and critical decomposition point) differ depending on the individual guest molecule.

FIG. 1 generally shows, as an example, the clathrate generation conditions of carbon dioxide in a coordinate plane in which the vertical axis represents the pressure represented by a log scale and the horizontal axis represents the temperature. As a result of examining the possibility of clathrate generation by changing the pressure and temperature of carbon dioxide, which is the clathrate generation condition, the clathrate was generated only in the hatched area between the two straight lines in FIG. (Hereinafter, this range is referred to as a “clath rate generation range”). The upper line is a pressure line for the saturated liquid of carbon dioxide, and the lower line is a clathrate generation limit line connecting the clathrate generation points where the temperature is the highest under a constant pressure. The intersection of the clathrate formation limit line and the saturated liquid pressure line is called a critical decomposition point. This critical decomposition point corresponds to a temperature much higher than 0 ° C., above which no clathrate is formed at any pressure.

A fifth aspect of the present invention (corresponding to the fifth aspect of the present invention) uses a medium as a refrigerant and has at least a load for cooling or releasing heat and a pump for conveying the medium to the load. The air conditioning refrigeration system according to any one of the first to fourth aspects of the invention, further comprising a secondary refrigeration cycle that forms a refrigeration cycle by using a regenerative heat storage unit, a load and a pump.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

First, the generation of carbon dioxide clathrate used in the embodiment of the present invention described below will be described as an example. The critical decomposition point of carbon dioxide, which is a guest molecule during clathrate formation, is described by Felix Franks: "Water-
A Comprehensive Treatise ", Plenum Press (197
As shown in Table 1 on page 123 of Table 3) as the temperature and pressure at Q ₂ , the temperature was 9.9 ° C. and the pressure was 44.4.
atm. The boiling point of carbon dioxide is 0 ° C. or lower, and the vapor pressure of the clathrate (0 ° C. or higher) generated by water and carbon dioxide becomes higher than the atmospheric pressure.

A description will be given of the generation of a hydrocarbon clathrate used in the embodiment of the present invention described below. The critical decomposition point of propane, for example, as a hydrocarbon that becomes a guest molecule during clathrate formation, is Felix Frank
s: "Water-A Comprehensive Treatise", Plenum
Press in Table 1 of the 124 pages (1973), as shown as temperature and pressure in the Q _2, temperature 5.7 ° C.,
The pressure is 5.45 atm. The boiling point of propane is 0 ° C. or less, and the clathrate (0 ° C.)
Above) becomes higher than the atmospheric pressure.

Accordingly, when the regenerative heat storage section is controlled at a temperature lower than the critical decomposition pressure of carbon dioxide or hydrocarbon (for example, propane) and lower than the critical decomposition temperature, a clathrate is generated.

Further, a clathrate-forming medium composed of water and carbon dioxide or a clathrate-generated medium composed of water and hydrocarbons may have an auxiliary gas or a surfactant for accelerating the formation of clathrate, and a melting point. Of course, additives for stabilizing the clathrate may be mixed. In addition to the above, an antioxidant, a heat stabilizer, an ultraviolet absorber, a fungicide and the like may be added. In addition, 2 consisting of water and clathrate
When circulating the next refrigerant, an anti-freezing agent for preventing freezing on the equipment wall may be added.

(First Embodiment) FIG. 2 is a configuration diagram showing an air conditioning refrigeration apparatus according to a first embodiment of the present invention.

In the air-conditioning refrigeration system according to the first embodiment, the cold storage unit 1 in which the clathrate is generated and stored is filled with water and used as a cold storage tank. The guest molecule is carbon dioxide.

The primary refrigeration cycle is directly connected to the regenerative heat storage section 1 containing carbon dioxide as a guest molecule during cold storage, and only carbon dioxide is separated from the medium of the secondary refrigeration cycle. The refrigerant becomes carbon dioxide.

The primary refrigeration cycle of this air conditioning refrigeration system is as follows:
The compressor 2, the four-way valve 3, the first heat exchanger 4, the first expansion device 5, and the cold storage unit 1 replaced with the evaporator are connected by pipes,
Branching between the first heat exchanger 4 and the first expansion device 5, the second expansion device 6, water and carbon dioxide as a medium in the regenerator 1 and carbon dioxide as a refrigerant of the primary refrigeration cycle. A pipe is connected between the cold storage unit 1 and the four-way valve 3 via a second heat exchanger 7 for indirectly exchanging heat, and a first opening / closing valve 8 is provided between the connection and the cold storage unit 1. ing.

One of the outlets of the first expansion device 5 is directly connected to the cold storage unit 1 where the clathrate is generated and stored, and the gas area of the cold storage unit 1 is connected to the accumulator 7 and the compression unit 7 via the first on-off valve 8. Machine 2 is connected to the suction line. Also,
The first throttle device 5 and the second throttle device 6 both use a variable throttle amount and can be closed, for example, an electronic expansion valve.

Compressor 2 directly connected to cold storage unit 1
In order to avoid that a small amount of refrigerating machine oil used for lubricating the cylinder of the compressor 2 is discharged from the discharge port of the compressor 2 and accumulated in the cold storage heat section 1 and cannot be returned to the compressor 2, It is desirable to use an oil separator 9 at the discharge port of the machine 2. For this purpose, an oil separator 9 is provided at the discharge port of the compressor 2, and an oil return pipe is connected to separate the refrigerating machine oil discharged from the compressor 2 together with the refrigerant and return the oil to the suction side.

The compressor 2 may be of an oil-free type if possible. As the oil-free type compressor, a reciprocating type can be used for a small size, and a screw type or a turbo type can be used for a large size. In this case, the oil separator 9 provided at the discharge port of the compressor 2 and the oil return pipe connected to the suction side can be omitted.

Further, carbon dioxide reacts with a very small amount of water to form carbonated water, which may corrode the metal surface. Therefore, the regenerative heat storage unit 1 and the compressor 2 that are directly connected
Between them, a dryer 10 is provided to prevent a small amount of water from being sucked into the compressor 2 at the same time as carbon dioxide as a guest molecule. In the present embodiment, the dryer 10 is arranged in the accumulator 11.

In the cold storage operation, the four-way valve 3 is set as shown by the dotted line in FIG. 2, the first throttle device 5 has an appropriate amount of throttle, the second throttle device 6 is closed, and the first on-off valve 8 is opened, and the refrigerant in the first refrigeration cycle circulates as shown by a dotted arrow in FIG. That is, the gas phase of the carbon dioxide which is the guest molecule in the cold storage unit 1 is sucked and compressed by the compressor 2 from the upper portion of the cold storage unit 1 via the first on-off valve 8, the four-way valve 3 and the accumulator 11. After that, it is led to the first heat exchanger 4 via the oil separator 9 and the four-way valve 3 to be condensed and liquefied. The condensed liquid is reduced to a specific pressure or lower through the first expansion device 5 to be in a low-temperature gas-liquid two-phase state, and is introduced into the cold storage heat section 1.

Here, heat exchange is performed by direct contact between low-temperature gas-liquid two-phase carbon dioxide, carbon dioxide as a medium in the cold storage unit 1 and water, and small droplets of carbon dioxide When mixed and the temperature drops below the critical decomposition temperature, a clathrate is generated. When the clathrate generation is completed, the cold storage heat unit 1 includes only the clathrate, the gas refrigerant of carbon dioxide, and water. Carbon dioxide functions as a guest molecule of the clathrate at the same time as the refrigerant of the primary refrigeration cycle.

At this time, the air-conditioning refrigeration system of the present embodiment sets the temperature and pressure of carbon dioxide in the cold storage unit 1 at a specific temperature and pressure which are below the critical decomposition point of the carbon dioxide clathrate, and If control means (not shown) for controlling a clathrate generation range sandwiched between a carbon saturation pressure line and a clathrate generation limit line is provided,
Further, the cold storage operation can be performed more efficiently. At this time, it is clear that the temperature and pressure of the low pressure section of the primary refrigeration cycle can be used instead of the temperature and pressure of carbon dioxide in the cold storage heat section 1.

The carbon dioxide of the primary refrigeration cycle is
Heat exchange by direct contact with water containing carbon dioxide in the secondary refrigeration cycle, the critical decomposition temperature of carbon dioxide clathrate is 0 ° C
Therefore, the evaporation temperature of the low-pressure section of the primary refrigeration cycle that generates cold heat can be raised to near the critical decomposition temperature of carbon dioxide clathrate, and the compression energy of the compressor during cold storage operation can be reduced, increasing the cold storage efficiency. Can help prevent global warming.

In the cooling operation, a secondary refrigeration cycle 14 which is directly connected to the cold storage unit 1 and is connected to the load 12 via the pump 13 is used to transmit cold to the load 12. The secondary refrigerant of water and clathrate is circulated to the load 12, the clathrate of carbon dioxide is heated and decomposed above the specified critical decomposition temperature, and returns to the cold storage unit 1.

In the cooling operation, the cold storage heat section 1
If the clath rate generation speed in the compressor and the load demand capacity of the secondary side are balanced, the primary side compressor 2 and the secondary side pump 13
May be controlled so that the circulation speed of the air is adjusted by the inverter.

The outlet of the first heat exchanger 4 acting as a condenser is branched into a plurality of parts, a plurality of first expansion devices 5 are provided, and carbon dioxide can be introduced into the plurality of regenerators 1. By controlling the opening and closing of the plurality of first expansion devices 5, it becomes possible to control the timing of the cold storage by the clathrate generation of the plurality of cold storage units 1. Also on the secondary refrigeration cycle side, it is possible to select which of the cold storage heat units 1 to perform cooling by the connection selection unit.

During the heat storage operation, the four-way valve 3 is set as shown by the solid line in FIG. 2, the first throttle device 5 has a small throttle amount, the second throttle device 6 has an appropriate throttle amount, and The on-off valve 8 is closed, and the refrigerant in the first refrigeration cycle circulates as shown by the solid arrow in FIG. That is, the gas phase of the carbon dioxide which is the guest molecule in the cold storage unit 1 is transferred from the cold storage unit 1 to the compressor via the first expansion device 5, the first heat exchanger 4, the four-way valve 3, and the accumulator 11. After being sucked and compressed by the second heat exchanger 2 to become high temperature, it is guided to the second heat exchanger 7 installed in the cold storage unit 1 via the oil separator 9 and the four-way valve 3, and the medium inside the cold storage unit 1 Heat is released to a mixture of carbon dioxide and water, which is condensed and liquefied. The condensate is reduced in pressure to a specific pressure or lower through the second expansion device 6 to be in a low-temperature gas-liquid two-phase state. The heat is absorbed to evaporate, and the compressor 2 passes through the four-way valve 3 and the accumulator 11.
Is sucked again.

Here, in the cold storage unit 1, the carbon dioxide in a high-temperature gas state and the carbon dioxide and water as the medium in the cold storage unit 1 indirectly exchange heat in the second heat exchanger 7. To
The temperature in the cold storage unit 1 rises and no clathrate is generated. Since the first on-off valve 8 is closed, the first on-off valve 8 is closed.
Since there is no supply of carbon dioxide to the cold storage unit 1 via the on-off valve, and the inside of the cold storage unit 1 is connected to the low pressure side of the primary refrigeration cycle via the first expansion device 5, the boiling point is low. The carbon dioxide evaporates preferentially and the first
It is collected on the next refrigeration cycle side. That is, the cold storage heat section 1
, The pressure rise on the secondary refrigeration cycle side is suppressed, and the pressure resistance design of the components constituting the secondary refrigeration cycle becomes easy. Similarly, when a mixture of hydrocarbon and water is used as a medium, hydrocarbons having a low boiling point are preferentially evaporated and recovered to the primary refrigeration cycle via the first expansion device 5. That is, since strongly flammable hydrocarbons do not circulate on the secondary refrigeration cycle side including the cold storage heat section 1, safety can be further improved.

During the heat dissipation operation, a secondary refrigeration cycle 14 which is directly connected to the cold storage unit 1 and is connected to the load 12 via the pump 13 is used to transfer heat to the load 12. Water from which carbon dioxide or hydrocarbons have been removed
The heat obtained by the heat exchanger 7 is radiated by the load 12 and returned to the cold storage unit 1.

Note that even during the heat dissipation operation, the cold storage heat section 1
If the amount of heat exchange in the (second heat exchanger 7) and the required load capacity of the secondary side are balanced, control is performed so that the circulation speed of the primary side compressor 2 and the secondary side pump 13 is adjusted by the inverter. Of course, you can do that.

A plurality of second heat exchangers 7 functioning as a plurality of condensers and a plurality of second expansion devices 6 are provided so that heat can be stored in the plurality of cold storage heat sections 1. If the opening / closing control is performed, it is possible to control the timing of the cold storage of the plurality of cold storage units 1. Further, also on the secondary refrigeration cycle side, it is possible to select which of the cold storage units 1 to perform heat release by the connection selection unit.

(Second Embodiment) FIG. 3 is a block diagram showing an air-conditioning refrigeration apparatus according to a second embodiment of the present invention. The same components as those in FIG. 2 are denoted by the same reference numerals. .

The air-conditioning refrigeration apparatus according to the second embodiment has an outlet side of the first heat exchanger 4 or the second heat exchanger 7 acting as a condenser in the primary refrigeration cycle and a suction side of the compressor 2. This is an example in which heat exchange is indirectly performed. The cold storage unit 1 is filled with water and is used as a cold storage tank. As the guest molecule, for example, carbon dioxide is used.

The primary refrigeration cycle of this air conditioning refrigeration system is as follows:
Compressor 2, four-way valve 3, first heat exchanger 4, first expansion device 5, third heat exchanger 15, second expansion device 6, cold storage unit 1,
The second heat exchanger 7 and the like are used as basic components. In the third heat exchanger 15, heat is indirectly exchanged between the outlet of the first heat exchanger 4 or the second heat exchanger 7 acting as a condenser and the suction line of the compressor 2. The first throttle device 5 and the second throttle device 6 both use a variable throttle amount and can be closed, for example, an electronic expansion valve.

In the cold storage operation, the four-way valve 3 is set as shown by the dotted line in FIG. 3, the first throttle device 5 has a small throttle amount, the second throttle device 6 has an appropriate throttle amount, and the first opening / closing operation. The valve 8 is opened, the second on-off valve 16 is closed, and the refrigerant in the first refrigeration cycle circulates as shown by the dotted arrow in FIG. That is, the gas phase of the carbon dioxide that is the guest molecule in the cold storage unit 1 passes through the first opening / closing valve 8, the four-way valve 3, the third heat exchanger 15, and the accumulator 11 from above the cold storage unit 1. After being sucked and compressed by the compressor 2, it is guided to the first heat exchanger 4 via the oil separator 9 and the four-way valve 3 to be condensed and liquefied. The condensed liquid is indirectly heat-exchanged with the low-temperature refrigerant sucked into the compressor 2 in the third heat exchanger 15 and is supercooled by the third heat exchanger 15 without being substantially reduced in pressure due to the small throttle amount in the first expansion device 5. The pressure is reduced by the second expansion device 6 to be in a low-temperature low-pressure gas-liquid two-phase state, and is introduced into the cold storage heat section 1.

Here, heat exchange is performed by direct contact between low-temperature gas-liquid two-phase carbon dioxide, carbon dioxide as a medium in the regenerative heat storage unit 1 and water, and small droplets of carbon dioxide When mixed and the temperature drops below the critical decomposition temperature, a clathrate is generated. When the clathrate generation is completed, the cold storage heat unit 1 includes only the clathrate, the gas refrigerant of carbon dioxide, and water. Carbon dioxide functions as a guest molecule of the clathrate at the same time as the refrigerant of the primary refrigeration cycle.

At this time, the air-conditioning refrigeration system according to the present embodiment sets the temperature and pressure of carbon dioxide in the cold storage unit 1 below a specific temperature and pressure, which are the critical decomposition points of carbon dioxide clathrate, and If control means (not shown) for controlling a clathrate generation range sandwiched between a carbon saturation pressure line and a clathrate generation limit line is provided,
Further, the cold storage operation can be performed more efficiently. At this time, it is clear that the temperature and pressure of the low pressure section of the primary refrigeration cycle can be used instead of the temperature and pressure of carbon dioxide in the cold storage heat section 1.

The carbon dioxide in the primary refrigeration cycle is
Heat exchange by direct contact with water containing carbon dioxide in the secondary refrigeration cycle, the critical decomposition temperature of carbon dioxide clathrate is 0 ° C
Therefore, the evaporation temperature of the low-pressure section of the primary refrigeration cycle that generates cold heat can be raised to near the critical decomposition temperature of carbon dioxide clathrate, and the compression energy of the compressor during cold storage operation can be reduced, increasing the cold storage efficiency. Can help prevent global warming.

In order to further reduce the compression energy of the primary refrigeration cycle, the outlet of the first heat exchanger 4 acting as a condenser and the suction line of the compressor 2 are indirectly heat-exchanged by the third heat exchanger 15. In addition, since the inlet side of the second expansion device 6 is easily supercooled, the high pressure of the primary refrigeration cycle is reduced, the compression energy of the primary refrigeration cycle is reduced, and the cold storage efficiency is improved. And contribute to the prevention of global warming.

During the cooling operation, a secondary refrigeration cycle 14 which is directly connected to the cold storage unit 1 and is connected to the load 12 via the pump 13 is used to transmit the cold to the load 12. The secondary refrigerant of water and clathrate is circulated to the load 12, the clathrate of carbon dioxide is heated and decomposed above the specified critical decomposition temperature, and returns to the cold storage unit 1. At this time, the guest molecule solution is converted into particles having a diameter smaller than about 100 microns using ultrasonic waves or the like.
It may be introduced into the cold storage unit 1.

On the other hand, during the heat storage operation, the four-way valve 3 is set as shown by the solid line in FIG.
Is an appropriate throttle amount, the second throttle device 6 is closed, and the first on-off valve 8
Is closed, the second on-off valve 16 is opened, and the refrigerant in the first refrigeration cycle circulates as shown by the solid line arrow in FIG. That is, the gas phase of the carbon dioxide that is the guest molecule in the cold storage unit 1 is transferred from the cold storage unit 1 to the check valve 17, the first heat exchanger 4, the four-way valve 3, the third heat exchanger 15, and the accumulator. 1
After being sucked by the compressor 2 through the compressor 1 and compressed to a high temperature, it is guided to the second heat exchanger 7 installed in the cold storage heat section 1 through the oil separator 9 and the four-way valve 3 to cool the cold storage. Heat is radiated to a mixture of carbon dioxide and water, which is a medium inside the heating unit 1, and condensed and liquefied. The condensed liquid is indirectly exchanged with the low-temperature refrigerant drawn into the compressor 2 by the third heat exchanger 15 via the second on-off valve 16 and supercooled, and then decompressed by the first expansion device 5. The first heat exchanger 4 acting as an evaporator absorbs heat from a heat source such as the atmosphere or circulating water to evaporate. The first heat exchanger 4 functions as an evaporator and evaporates. Is sucked again.

Here, in the cold storage unit 1, the carbon dioxide in a high temperature gas state and the carbon dioxide and water as the medium in the cold storage unit 1 indirectly exchange heat in the second heat exchanger 7. To
The temperature in the cold storage unit 1 rises and no clathrate is generated. Since the first on-off valve 8 is closed, the first on-off valve 8 is closed.
There is no supply of carbon dioxide to the cold storage heat section 1 via the on-off valve 8, and the inside of the cold storage heat section 1 is connected to the low pressure side of the primary refrigeration cycle via the check valve 17, so that the boiling point is low. The carbon dioxide evaporates preferentially and is collected on the primary refrigeration cycle side via the check valve 17. That is, the pressure increase on the secondary refrigeration cycle side including the cold storage heat section 1 is suppressed, and the pressure resistance design of the components constituting the secondary refrigeration cycle becomes easy.
Similarly, when a mixture of hydrocarbon and water is used as the medium, the hydrocarbon having a low boiling point evaporates preferentially and the check valve 1
7 and is collected on the primary refrigeration cycle side. That is, since strongly flammable hydrocarbons do not circulate on the secondary refrigeration cycle side including the cold storage heat section 1, safety can be further improved.

In order to further reduce the compression energy of the primary refrigeration cycle, the outlet of the second heat exchanger 7 acting as a condenser and the suction line of the compressor 2 are indirectly heat-exchanged by the third heat exchanger 15. In this case, the inlet side of the first expansion device 5 is easily supercooled, so that the high pressure of the primary refrigeration cycle is reduced, the compression energy of the primary refrigeration cycle is reduced, and the heat storage efficiency is improved. And contribute to the prevention of global warming.

During the heat dissipation operation, a secondary refrigeration cycle 14 which is directly connected to the cold storage heat section 1 and is connected to the load 12 via the pump 13 is used to transmit heat to the load 12. Water from which carbon dioxide or hydrocarbons have been removed
The heat obtained by the heat exchanger 7 is radiated by the load 12 and returned to the cold storage unit 1.

The primary-side compressor 2 and the secondary-side pump 1 during the heat-dissipating operation described in the first embodiment.
Needless to say, the cooperative control of No. 3 and the timing control of the heat storage by the plurality of cold storage units 1 are also possible in the second embodiment.

In addition, since heat is generated during cold storage by generation of carbon dioxide or hydrocarbon clathrate, and an endothermic effect occurs during decomposition of clathrate, a plurality of cold storage units 1 are provided so that heat can be exchanged with each other. Alternatively, heat recovery at the time of decomposition may be performed between the plurality of cold storage units 1.

The air-conditioning refrigeration apparatus according to the first and second embodiments has been described as including the secondary refrigeration cycle of the present invention. However, the present invention is not limited to this. May be provided with a primary refrigeration cycle and a cold storage unit, and the cold or hot heat stored or stored in the cold storage unit may be used by another means.

In the air-conditioning and refrigeration apparatus according to the second embodiment described above, the supercooling is increased in the third heat exchanger 15 during both the cold storage operation and the heat storage operation. However, the present invention is not limited to this. Instead, the third heat exchanger may be operated only during the cold storage operation or the heat storage operation.

In the air-conditioning refrigeration system according to the first and second embodiments, the first expansion device 5,
Although the second throttle device 6 has been described as an electronic expansion valve, for example, which has a variable throttle amount and can be closed, the present invention is not limited to this.
It may be replaced with a fixed throttle amount, for example, a combination of a capillary tube and an on-off valve.

The air-conditioning refrigerating apparatus according to the first and second embodiments is mainly described using carbon dioxide and water as a medium. However, the present invention is not limited to this. Decomposition temperature higher than 0 ° C., for example R170, R1270, RC270, R
290, R600a) and water.

[0063]

As is apparent from the above description,
In the first invention (corresponding to the invention described in claim 1),
When cold heat is generated, a mixed medium of liquefied carbon dioxide and water or a mixed medium of liquefied hydrocarbon and water is used as a medium for the secondary refrigeration cycle, and the latent heat of carbon dioxide or hydrocarbons during gasification is large, By reducing the circulation amount of the secondary refrigerant circulated to the load, the pump power of the secondary refrigeration cycle can be reduced, the peak power amount during the daytime in summer can be reduced, and it can contribute to the prevention of global warming. At this time, the disadvantage of the strong flammability of the hydrocarbon can be reduced as compared with the leakage during circulation of the hydrocarbon alone because the medium is mixed with water.

In the second aspect of the present invention (corresponding to the second aspect of the present invention), if heat is exchanged between the outlet of the condenser and the suction line of the compressor by means of a heat exchanger, the inlet side of the expansion device can easily pass through. Cooled, the high pressure of the primary refrigeration cycle can be reduced, and the compression energy of the compressor can be reduced. In particular, during the cold storage operation, the low pressure of the primary refrigeration cycle due to the generation of the clathrate increases, and the cold storage efficiency during the cold storage operation To increase
It can contribute to the prevention of global warming.

In the third aspect of the present invention (corresponding to the third aspect of the present invention), during cold storage in which the primary refrigeration cycle is directly connected to the cold storage heat section, carbon dioxide or hydrocarbons are removed from the medium of the secondary refrigeration cycle. Is separated and used as a refrigerant for the primary refrigeration cycle. Here, the carbon dioxide or hydrocarbons in the primary refrigeration cycle exchange heat by direct contact with water containing carbon dioxide or hydrocarbons in the secondary refrigeration cycle, and carbon dioxide clathrate or hydrocarbon (for example, R
170, R1270, RC270, R290, R600
a) Since the critical decomposition temperature of the clathrate is higher than 0 ° C., the evaporation temperature of the low-pressure part of the primary refrigeration cycle that generates cold heat is increased to near the critical decomposition temperature of the carbon dioxide clathrate or the hydrocarbon clathrate, The compression energy of the compressor at the time of cold storage can be reduced, and the cold storage efficiency can be increased, contributing to the prevention of global warming.

When the regenerative heat storage unit performs heat exchange without direct contact between the medium of the regenerative heat storage unit and the refrigerant of the primary refrigeration cycle, it also applies when carbon dioxide is used as the refrigerant of the primary refrigeration cycle. It is possible to prevent the inside of the cold storage heat section from being in a high pressure state, and to reduce the risk of the cold storage heat section exploding. Alternatively, if hydrocarbons are used as the refrigerant of the primary refrigeration cycle, not only can the pressure of the primary refrigeration cycle be reduced, but also the primary refrigeration cycle can be performed by separating only the highly flammable hydrocarbons from the medium of the secondary refrigeration cycle. It can be recovered in the cycle, and the strong flammability of hydrocarbons can be greatly reduced because it is separated from the load side.

According to a fourth aspect of the present invention (corresponding to the fourth aspect of the present invention), a clathrate formed by direct contact between water and carbon dioxide or water and hydrocarbon is used as a suitable cold storage material for an air-conditioning refrigeration system. And as a working medium. That is, since the critical decomposition temperature of the carbon dioxide clathrate or the hydrocarbon clathrate is higher than 0 ° C., the evaporation temperature of the low-pressure section of the primary refrigeration cycle that generates cold heat is increased as compared with ice cold storage, and the compressor during cold storage is used. Energy can be reduced and the efficiency of cold storage can be increased, contributing to the prevention of global warming.

According to the fifth aspect of the present invention (corresponding to the fifth aspect of the present invention), it is possible to efficiently transfer cold or warm heat of the cold storage section to a load remote from the cold storage section.

[Brief description of the drawings]

FIG. 1 is a coordinate diagram showing conditions for generating a clathrate of carbon dioxide.

FIG. 2 is a configuration diagram illustrating an air conditioning refrigeration apparatus according to the first embodiment of the present invention.

FIG. 3 is a configuration diagram illustrating an air conditioning refrigeration apparatus according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram showing a conventional ice regenerative air conditioning refrigeration apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cold storage part 2 Compressor 3 Four-way valve 4 1st heat exchanger 5 1st expansion device 6 2nd expansion device 7 2nd heat exchanger 8 1st on-off valve 9 Oil separator 10 Dryer 11 Accumulator 12 Load 13 Pump 14 Secondary refrigeration cycle 15 Third heat exchanger 16 Second on-off valve 17 Check valve 21 Ice regenerator 22 Compressor 23 Condenser 24 Throttling device 25 Evaporator 26 Accumulator 27 Load 28 Pump 29 Secondary refrigeration cycle

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Noriho Okaza 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Yuji Yoshida 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.F-term (reference) 3L092 TA11 TA16 UA02 UA03 UA24 UA33 VA02 VA07 WA05 WA15 XA28

Claims (5)

[Claims] 1. A primary refrigeration cycle having at least a compressor, a four-way valve, a first heat exchanger and a throttling device, and a regenerative heat storage unit for performing regenerative or thermal storage using carbon dioxide and water or hydrocarbons and water as a medium. The connection configuration between the cold storage heat section and the primary refrigeration cycle is such that the medium and the refrigerant of the primary refrigeration cycle come into direct contact with each other to exchange heat when storing cold, and the medium and the first medium during heat storage. An air conditioning refrigeration apparatus characterized in that heat is exchanged in the second heat exchanger without direct contact with the refrigerant of the next refrigeration cycle. 2. The primary refrigeration cycle exchanges heat between an outlet line of the first heat exchanger or an outlet line of the second heat exchanger acting as a condenser and a suction line of the compressor. The air-conditioning refrigeration apparatus according to claim 1, further comprising a heat exchange unit for performing the heat exchange. 3. The refrigerant of the primary refrigeration cycle is carbon dioxide when the medium is carbon dioxide and water, and the refrigerant of the primary refrigeration cycle is hydrocarbon when the medium is hydrocarbon and water. 3. The method according to claim 1, wherein
An air conditioning refrigeration apparatus according to claim 1. 4. During cold storage, the temperature and pressure of the medium in the cold storage heat section are equal to or lower than a specific temperature and pressure that are critical decomposition points of the clathrate of the medium, and the saturation pressure line of the medium and the clathrate generation are performed. The air conditioning refrigeration apparatus according to any one of claims 1 to 3, further comprising control means for controlling a clath rate generation range sandwiched between limit lines. 5. The method according to claim 5, wherein the medium is a refrigerant, and at least a load for performing cooling or heat radiation and a pump for transferring the medium to the load are provided, and a refrigeration cycle is performed by the cold storage heat unit, the load, and the pump. The air conditioning refrigeration apparatus according to any one of claims 1 to 4, further comprising a secondary refrigeration cycle configured.