JP2010271000A - Heat storage type refrigerating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a freezing-refrigerating system having a new configuration interconnecting both cycles via a heat storage tank to eliminate the "synchronism of cooling actions of respective refrigerating cycles on low and high temperature sides" and "necessity of a heat exchanger for directly interconnecting the respective refrigerating cycles" in the conventional two refrigerating cycles. <P>SOLUTION: This heat storage type refrigerating system includes: a first refrigerating cycle including a high-temperature side condenser 1 and a high-temperature side evaporator 3; a second refrigerating cycle including a low-temperature side condenser 7 and a low-temperature side evaporator 11; the one heat storage tank 5 storing the evaporator 3 of the first refrigerating cycle and the condenser 7 of the second refrigerating cycle; and a heat storage medium 6 stored within the heat storage tank 5. The heat storage medium 6 within the heat storage tank 5 is cooled by the evaporator 3 of the first refrigerating cycle to store cold, and the condenser 7 of the second refrigerating cycle is cooled by the cold stored in the heat storage medium 6 within the heat storage tank 5 to condense a refrigerant in the second refrigerant cycle. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention includes a conventionally used binary refrigeration system, and a heat storage system (Patent No. 3689283, Patent No. 3742043, Patent No. 385965, and Patent No. 3856572) that has been filed by the present applicant and has already been patented. The present invention relates to a heat storage type refrigeration system that is efficient and can clear environmental problems.

  In refrigeration factories, food / agricultural products processing factories, distribution bases such as markets and distribution warehouses, and retail stores such as supermarkets and convenience stores, chlorofluorocarbon refrigerant devices (refrigeration systems) are used for refrigeration, refrigeration and air conditioning. Has been. However, the use of CFCs has been restricted due to problems in the natural environment such as global warming. Therefore, in recent years, natural refrigerants (substances that exist in nature such as carbon dioxide and ammonia) that have excellent energy saving and low environmental impact are used as refrigerants instead of greenhouse gases such as chlorofluorocarbons. Air conditioners have been developed.

  Various systems that use carbon dioxide as a refrigerant for freezing, refrigeration, and air conditioning have been proposed. However, since the critical temperature of carbon dioxide is 31.1 ° C. and the critical pressure is 7.38 MPa, the temperature in summer is 40 In Japan, where the temperature rises to ° C, the temperature becomes higher than the critical temperature and becomes a supercritical gas, and there are many problems to be solved in practice.

Specifically, if carbon dioxide is used as a refrigerant in a refrigeration system for refrigeration and refrigeration equipment at ambient temperature, for example, high pressure during condensation on the refrigeration cycle and evaporation during evaporation (cooling) There is a problem that the difference is too large, for example, the difference from the pressure is 7 Mpa or more.
Therefore, recently, one refrigeration cycle as shown in FIG. 11 is divided into a low temperature side (using carbon dioxide refrigerant) and a high temperature side (using refrigerants such as chlorofluorocarbon, ammonia, hydrocarbons), and a low temperature side condenser and a high temperature side evaporation. A refrigeration apparatus (referred to as a binary refrigeration cycle) that directly exchanges heat with a heat exchanger that plays the role of a refrigerator has been proposed (Non-patent Document 1).

The Japan Society of Refrigerating and Air Conditioning Engineers issued on November 30, 2007 "Advanced Refrigeration Examination Text by SI", page 29

  The two-way refrigeration cycle is composed of a refrigerator (group) that uses respective refrigerants on both the low temperature side and the high temperature side. In this current system, the high-temperature side cycle and the low-temperature side cycle constitute one cooling cycle via a heat exchanger (refrigerant evaporation type condenser in FIG. 11). Therefore, in order to enable the cooling operation on the low temperature side, it is necessary to always operate the high temperature side.

  In this system, since the condensation temperature on the low temperature side is influenced by the temperature of the evaporator on the high temperature side, the evaporator function (cooling function) on the high temperature side is stopped when the cooling cycle on the high temperature side is stopped. As a result, the heat exchanger (cold condenser on the low temperature side) connecting the high temperature side and the low temperature side is directly affected by the atmospheric temperature as the temperature changes (increases) in various parts of the system based on the outside air temperature, and its saturation temperature. The temperature of the low-temperature side refrigerant rises to the same time, and at the same time the pressure rises to a high pressure of 7-8 Mpa. If an attempt is made to build a system in a structure that can withstand such a pressure increase, a heavy equipment structure is required and the cost becomes high.

  In the recently developed ammonia refrigerator, a so-called pump circulation system that cools and circulates carbon dioxide brine has been put into practical use, and in order to eliminate the need for heavy equipment as described above, as a countermeasure against pressure rise, For the purpose of protection, measures are taken in the system to prevent the pressure from rising due to a safety valve or the like (Patent Document 1).

Japanese Patent No. 3458310

In this document, a liquid pump system that condenses carbon dioxide with an evaporator of an ammonia refrigerator and circulates condensed carbon dioxide refrigerant to the load side by a pump and a load side at a position lower than the carbon dioxide condenser are installed. Thus, a natural circulation system is used in which the carbon dioxide gas liquid is supplied to the load side by gravity, and the above carbon dioxide evaporated on the load side is condensed by the condenser.
However, in this system, when the ammonia refrigerator for cooling carbon dioxide gas (high-source refrigerator) fails, the carbon dioxide gas system is at a saturation pressure corresponding to the ambient temperature in which it is placed (the surrounding area on the condenser side with a large amount of refrigerant). There is a high risk of being released from the safety valve to the atmosphere. By the way, item 19 of the relationship example criteria according to the current high-pressure gas safety law refrigeration safety rules. The design pressure section provides for the setting of this type of design pressure. As a result, a safety valve is provided in the carbon dioxide gas system, and the set pressure of the safety valve is set to 2 to 4 Mpa, and many examples are delivered.

In the above background, the present invention relates to “simultaneity of cooling action of each refrigeration cycle on the low temperature side and the high temperature side” in the conventional binary refrigeration cycle, and an integrated design of the low temperature side refrigerator and the high temperature side refrigerator ( By providing a regenerative refrigeration system having a new configuration in which both cycles are connected via a heat storage tank in order to eliminate the need for a heat exchanger that directly couples each refrigeration cycle). The object is to solve the above problems.
With this configuration, the present invention promotes the independence of the operation of the refrigerator, the independence of the refrigerator capacity design, and the independence of the service as compared with the conventional system, and improves "reliability" and "ensures higher safety at the time of failure" ”,“ Promoting the leveling of power usage through the active use of nighttime electric power by nighttime heat storage and thereby reducing the amount of electricity used, ”can be achieved.

Therefore, the present invention provides means for solving the problems adopted by the present invention.
A first refrigeration cycle having a high temperature side condenser 1 and a high temperature side evaporator 3;
A second refrigeration cycle having a low temperature side condenser 7 and a low temperature side evaporator 11;
One heat storage tank 5 for accommodating the high temperature side evaporator 3 of the first refrigeration cycle and the low temperature side condenser 7 of the second refrigeration cycle;
A heat storage medium 6 accommodated in the heat storage tank,
The heat storage medium in the heat storage tank is cooled by the high temperature side evaporator of the first refrigeration cycle to store cold heat, and the low temperature side condenser of the second refrigeration cycle is stored by the cold heat stored in the heat storage medium in the heat storage tank. Cool,
It is a heat storage type refrigerating system characterized by condensing the refrigerant of the 2nd refrigerating cycle.
A plurality of first refrigeration cycles and a plurality of second refrigeration cycles are prepared, and a plurality of first side refrigeration cycle high temperature side evaporators and a plurality of second refrigeration cycle low temperature side condensers are provided in one heat storage tank. It is a heat storage type refrigeration system characterized by having arranged.
The refrigerant of the first refrigeration cycle is a natural refrigerant such as ammonia, and the refrigerant of the second refrigeration cycle is carbon dioxide gas.
Further, the heat storage type refrigeration system is provided with a load circuit 15a for pumping the heat storage medium in the heat storage tank and operating the load 15.
Further, a heat storage tank heat exchanger for exchanging heat with the heat storage medium in the heat storage tank and a load circulation circuit 16 having a load are provided, and a carbon dioxide refrigerant is circulated in the circulation circuit 16. System.
The heat storage refrigeration system is characterized in that a circulation pump is provided in series with the heat storage tank heat exchanger 18 in the load circulation circuit 16.
The refrigerant of the load circulation circuit may be naturally circulated using gravity to provide a heat storage type refrigeration system.
Moreover, the 1st freezing cycle which has the high temperature side condenser 1 and the high temperature side evaporator 3,
A second refrigeration cycle having a low temperature side condenser 7 and a low temperature side evaporator 11;
One heat storage tank 5 accommodating the high-temperature side evaporator 3 of the first refrigeration cycle;
A heat storage medium 6 accommodated in the heat storage tank,
A heat storage medium circulation circuit 14 that pumps up the heat storage medium of the heat storage tank and cools the low-temperature side condenser of the second refrigeration cycle by the cold energy stored in the heat storage medium in the heat storage tank is provided,
The heat storage medium in the heat storage tank is cooled by the high temperature side evaporator of the first refrigeration cycle to store cold heat, and the condenser of the second refrigeration cycle is cooled by the heat storage medium circulation circuit 14. Type refrigeration system.
The regenerative refrigerant is characterized in that the refrigerant in the first refrigeration cycle is a natural refrigerant such as ammonia, and the refrigerant in the second refrigeration cycle is one of carbon dioxide, ammonia, HC refrigerant, and chlorofluorocarbon refrigerant. System.
The heat storage refrigeration system is characterized in that a load is provided in the heat storage medium circulation circuit.
The heat storage refrigeration system includes a plurality of heat storage medium circulation circuits for pumping up the heat storage medium of the heat storage tank.
The heat storage refrigeration system is characterized in that a load is provided in the plurality of heat storage medium circulation circuits.
Moreover, the 1st freezing cycle which has the high temperature side condenser 1 and the high temperature side evaporator 3,
A second refrigeration cycle having a low temperature side condenser 7 and a low temperature side evaporator 11;
A brine pipe having a brine circulation pump and an ice making coil, and a brine pipe capable of exchanging heat with the high temperature side evaporator of the first refrigeration cycle;
One heat storage tank 5 that houses the ice making coil and the low temperature side condenser 7 of the second refrigeration cycle;
A heat storage medium 6 accommodated in the heat storage tank,
The brine is cooled by the high-temperature side evaporator of the first refrigeration cycle, and the cooled brine is passed through an ice making coil in a heat storage tank to cool the heat storage medium to store cold heat, and to the heat storage medium in the heat storage tank. The low-temperature side condenser of the second refrigeration cycle is cooled by the stored cold heat,
It is a heat storage type refrigerating system characterized by condensing the refrigerant of the 2nd refrigerating cycle.

  In the present invention, the refrigerant used in each refrigeration cycle (first refrigeration cycle, second refrigeration cycle) moves the heat on the low temperature side to the high temperature side via the heat storage medium in the heat storage tank. The coefficient is lower than that of the conventional method because it passes through a heat storage medium (brine, water, etc.), but the coefficient of performance of the refrigeration cycle on the high temperature side is improved by the heat storage operation at night, and the coefficient of There is more to compensate for the decline.

  By installing a heat storage tank, heat storage operation is performed with the high-temperature side refrigerator in the first refrigeration cycle at night (may be during the day), for example, and the low-temperature side condensation in the second refrigeration cycle is performed with this low-temperature heat during the day. The vessel can be cooled. Thus, even if the high-temperature side refrigerator breaks down, it is possible to have time to avoid the pressure increase due to the temperature increase of the low-temperature side condenser due to the cold heat stored in the heat storage tank. Moreover, the electric power used in the daytime can be transferred to the nighttime by storing the heat at night with respect to the load during the daytime. Further, the high temperature side refrigerator also has a low outside air temperature during night operation, and can be operated efficiently. Time difference operation and night electricity charges are applied, which is economically advantageous. Further, it is not always necessary to simultaneously operate the high temperature side refrigerator in the first refrigeration cycle and the low temperature side refrigerator in the second refrigeration cycle.

Whereas the conventional type can only operate the low-temperature refrigerator (low-source refrigerator) and the high-temperature side refrigerator (high-source refrigerator) at the same time, this system operates each refrigerator (one to multiple units). Independence is possible, and independence of refrigerator design, installation capacity and service is promoted.
In other words, the conventional two-way refrigerator is a low-temperature side refrigerator (low-source refrigerator) and a high-temperature side refrigerator (high-source refrigerator) that are integrally assembled via a cascade heat exchanger, and the low-temperature side refrigerator is operated. In order to achieve this, the high temperature side refrigerator must be operated simultaneously. According to the present invention, the integrated consistency between the capacity of the high temperature side refrigerator and the capacity of the low temperature side refrigerator is not required. For example, even if the capacity of the high temperature side refrigerator is equal to or less than the capacity of the low temperature side refrigerator, the operation time is reduced. It is possible to measure the consistency of the load on the high temperature side and the low temperature side by taking into consideration (see the following formula).
High temperature side refrigeration functional force x operation time ≥ Low temperature side refrigeration functional force x operation time

The present invention is a system for heat exchange by interposing a heat storage medium (brine, water, etc.) of a heat storage tank with respect to a conventional cascade heat exchanger. This form is positioned as a “separate type”, whereas the conventional low and high level refrigerators are “integrated”. According to the present invention, the operation of each refrigerator is such that the high temperature side refrigerator (heat storage refrigerator) operates mainly at night, and the low temperature side refrigerator (refrigeration refrigerator) operates during the day with its cold. it can.
That is, by interposing a heat storage tank, a plurality of high-temperature side refrigerators and low-temperature side refrigerators can be installed in various sizes (multi-connection). In addition, combinations of refrigerants used in different refrigerators (for example, carbon dioxide refrigerators, Freon and ammonia refrigerators) are also free. For this reason, the degree of freedom in system design can be expanded and service reliability can be further improved in response to various future user requests.

  Further, if the high-temperature side refrigerator is used as a heat pump and is switched and connected so that the cooling brine heat of the low-temperature side condenser can be used, a heat recovery operation of refrigeration and refrigeration heat can be performed as a heat source for heating or hot water supply.

Even in a system in which a plurality of units on the air conditioning side, the refrigeration side, and the refrigeration side are connected by local piping, there is no emission of warming gas even if there is a leak in the brine piping instead of the chlorofluorocarbon refrigerant piping.
And so on.
In addition, when the high temperature side refrigerant | coolant is ammonia, since it is a toxicity and a flammable gas, the local multi-connection is not preferable. Since hydrocarbons are also flammable gases, there are restrictions on the amount of charge used. Fluorocarbons are warming gases, and these refrigerants should avoid local piping as much as possible to prevent gas leakage.

1 is a configuration diagram of a regenerative refrigerating system according to a first embodiment of the present invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 2nd Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 3rd Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 4th Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 5th Example of this invention. It is a block diagram of the thermal storage type freezing system which concerns on 6th Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 7th Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 8th Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 9th Example of this invention. It is a block diagram of the thermal storage type refrigerating system which concerns on 10th Example of this invention. It is a block diagram of a conventionally well-known binary refrigeration cycle in which one refrigeration cycle is divided into a low temperature side and a high temperature side, and heat is exchanged directly with a heat exchanger that plays the role of a low temperature side condenser and a high temperature side evaporator.

  The present invention includes at least one heat storage tank that houses a first refrigeration cycle, a second refrigeration cycle, a high temperature side evaporator of the first refrigeration cycle, and a low temperature side condenser of the second refrigeration cycle; A heat storage medium housed in the heat storage tank, cools the heat storage medium in the heat storage tank by the evaporator of the first refrigeration cycle, stores cold heat, and stores heat in the heat storage medium in the heat storage tank Is used to cool the condenser of the second refrigeration cycle and condense the refrigerant of the second refrigeration cycle.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a preferred embodiment of a heat storage refrigeration system according to the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of a heat storage refrigeration system according to a first embodiment of the present invention.

In FIG. 1, a heat storage type refrigeration system (including a refrigeration system) of the first embodiment includes a first refrigeration cycle (hereinafter referred to as a high temperature side refrigeration cycle) S1, a second refrigeration cycle (hereinafter referred to as a low temperature side refrigeration cycle) S2, and a heat storage. And a tank 5.
The high temperature side refrigeration cycle S1 includes a high temperature side condenser 1, a high temperature side compressor 2, a high temperature side evaporator 3, and a high temperature side expansion valve 4, as in the known refrigeration cycle, and these are arranged and connected as shown in the figure. ing. The high temperature side evaporator 3 has a function of giving cold to the heat storage medium 6 of the heat storage tank 5 as the refrigerant in the high temperature side refrigeration cycle evaporates, and the heat storage tank 5 stores the cold heat given from the first refrigeration cycle in the heat storage tank. It has the function to store in the heat storage medium. Moreover, although this high temperature side refrigerating cycle S1 uses ammonia gas as a refrigerant | coolant, it is also possible to use other refrigerants, such as a Freon and a hydrocarbon.

The low temperature side refrigeration cycle S2 is a low temperature side condenser 7, a low temperature side compressor 8, a low temperature side load (evaporator) 11, a low temperature side expansion valve 9, and a low temperature side liquid receiver, which are conventionally known, like the high temperature side refrigeration cycle. And the like are arranged and connected as shown in the figure. In this example, carbon dioxide gas is used as the refrigerant for the low temperature side refrigeration cycle, but other refrigerants (ammonia, HC refrigerant, chlorofluorocarbon refrigerant, etc.) can also be used.
The high temperature side evaporator 3 of the high temperature refrigeration cycle S1 and the low temperature side condenser 7 of the low temperature refrigeration cycle S2 are stored in the heat storage tank 5 and stored in the heat storage tank 5 (brine, water, etc.). ) Soaked in 6.

The operation of the heat storage type refrigeration system having the above configuration will be described.
First, the cold heat is produced by operating the high-temperature side refrigeration cycle S1 prior to the cooling target load process (or simultaneous processing), and the cold heat is stored in the heat storage medium 6 of the heat storage tank 5 shown in FIG.
The low temperature refrigeration cycle S2 cools the refrigeration load existing in the low temperature region while using the cold energy stored in the heat storage tank 5 for condensation.

  As described above, the refrigerant used in each of the refrigeration cycles S1 and S2 moves the cold on the low temperature side to the high temperature side via the heat storage medium in the heat storage tank, and the coefficient of performance during this period is the coefficient of performance for the heat storage medium (brine, However, the coefficient of performance of the refrigeration cycle on the high temperature side is improved by the heat storage operation at night, and the decrease in the coefficient of performance due to heat exchange in the heat storage tank is more than compensated.

By installing a heat storage tank as in this example, for example, heat storage operation is performed with a high-temperature side refrigerator at night (may be during the day), and a low-temperature side condenser (heat radiator) is connected with this low-temperature heat during the day. Can be cooled. As a result, even if the high-temperature side refrigerator breaks down, it is possible to have time to avoid a pressure increase accompanying a temperature increase on the low temperature side due to the cold heat stored in the heat storage tank. By storing heat at night against the load during the daytime, the electric power used during the daytime can be transferred to the nighttime. In addition, the high temperature side refrigerator also has a low outside air temperature during night operation, and can be operated efficiently. Time difference operation is possible, and the night electricity charge is applied, which is advantageous for economy.
In contrast to the conventional low temperature refrigerator (low-source refrigerator) and high-temperature side refrigerator (high-source refrigerator) that can only be operated at the same time, this system operates each refrigerator (one to multiple units). Independence is possible, and independence of refrigerator design, installation capacity and service is promoted.

  If the high-temperature side refrigerator is used as a heat pump and is switched and connected so that the refrigerant heat of the low-temperature side radiator can be used, a heat recovery operation of refrigeration and refrigeration heat can be performed as a heat source for heating or hot water supply.

Even in a system in which multiple units on the air conditioning side, refrigeration, and refrigeration side are connected by local piping, warming gas is not released even if there is a leak in the brine piping instead of the refrigerant piping.
When the refrigerant is ammonia, it is not preferable to connect the refrigerant piping to the local manned space because of toxicity and flammable gas. Since hydrocarbons are also flammable gases, there are restrictions on the amount of charge used. Fluorocarbons are warming gases, and these refrigerants should avoid local piping as much as possible to prevent gas leakage. The present invention is separated from the high-temperature refrigerator side (ammonia refrigerant) in the heat storage tank, and is safe in the manned space due to the brine piping and the carbon dioxide gas refrigerant piping.

Next, a second embodiment will be described with reference to the drawings. FIG. 2 is a configuration diagram of a refrigeration system according to the second embodiment of the present invention.
The difference from the first and second embodiments is that the evaporators of the plurality of high temperature side refrigeration cycles are arranged in the heat storage medium (brine, water, etc.) of the heat storage tank, and the plurality of low temperature side refrigerations. The condenser of the cycle is arranged, the cold storage can be stored in the heat storage medium of the heat storage tank by operating each high-temperature side refrigeration cycle, and the heat storage medium in the heat storage tank stored in the heat storage tank is arranged in the heat storage tank In addition, the condensers of a plurality of low-temperature refrigeration cycles can be cooled.

Even in the above-described configuration, as in the first embodiment, the manufacture of cold heat operates the high-temperature side refrigeration cycle prior to the cooling target load processing (or may be performed simultaneously), and stores the cold heat in the heat storage tank shown in FIG. The low-temperature refrigeration cycle cools the refrigeration load existing in the low-temperature region while using the cold energy stored in the heat storage tank for condensation.
In the present invention, since a plurality of high temperature side refrigeration cycles, low temperature side refrigeration cycle evaporators and condensers are arranged in one heat storage tank, the heat storage tank can be shared, which is economical.

Next, a third embodiment will be described with reference to the drawings. FIG. 3 is a configuration diagram of a refrigeration system according to a third embodiment of the present invention.
In the third embodiment, a load circuit 15a is connected to the heat storage tank and a load 15 is provided in the circuit in order to effectively use the cold heat in the heat storage tank. In this example, by operating the heat storage medium circulation pump 17a, the heat storage medium in the heat storage tank can be circulated to cool the load, and the apparatus can be simplified. This load is a medium temperature cooling device in the vicinity of 0 ° C. that can be cooled by a heat storage medium.

Next, a fourth embodiment will be described with reference to the drawings. FIG. 4 is a configuration diagram of a refrigeration system according to the fourth embodiment of the present invention.
In the fourth embodiment, in order to effectively use the cold energy in the heat storage tank, an independent load circulation circuit having a heat exchanger in the heat storage tank (CO2 refrigerant is circulated in the independent circuit to exchange heat with the heat storage medium. A circulation circuit 16 for exchanging heat through a vessel) is connected, and a load 15 is provided in this circuit. In this example, by operating the CO2 circulation pump 17, the CO2 refrigerant in the load circulation circuit 16 can be circulated, the load 15 can be cooled, and the apparatus can be simplified. Further, Patent Document 1 has time to avoid a pressure increase even when the high-temperature side refrigerator is out of order.

Next, a fifth embodiment will be described with reference to the drawings. FIG. 5 is a configuration diagram of an improved refrigeration system of the fourth embodiment of the present invention.
In the fifth embodiment, in order to effectively use the cold heat in the heat storage tank, an independent CO2 circulation circuit having a heat exchanger is arranged in the heat storage tank as in the fourth embodiment, and a load 15 is placed in this circuit. And the circulation medium (CO2) is naturally circulated using gravity (head). In this example, since the medium in the load circulation circuit 16 can be circulated using the head, the apparatus can be simplified. Further, Patent Document 1 has time to avoid a pressure increase even when the high-temperature side refrigerator is out of order.

Next, a sixth embodiment will be described with reference to FIG. 6. FIG. 6 is a configuration diagram of a refrigeration system according to a sixth embodiment of the present invention.
The difference from the first embodiment is that only the high temperature side evaporator 3 is arranged in the heat storage tank 5, and the low temperature side condenser is not arranged. The heat storage tank is connected to a heat storage medium circulation circuit 14 having a heat exchanger 7 that provides cold heat to the condenser 7 of the low temperature side refrigeration cycle. In this system, the heat storage medium in the heat storage tank is pumped up by the heat storage medium circulation pump, and the low-temperature side condenser is cooled by the heat exchanger. This embodiment also operates in the high-temperature side refrigeration cycle to operate the heat storage tank. It can be used to store cold energy. A condenser 7 of a low temperature side refrigeration cycle is disposed in the heat exchanger in the circulation circuit 14, and this heat exchanger can be installed near the load side far from the heat storage tank.

Next, a seventh embodiment will be described with reference to FIG. 7. FIG. 7 is a configuration diagram of a refrigeration system according to the seventh embodiment of the present invention.
The seventh embodiment is an improved version of the sixth embodiment, and is different in that a load 15 is provided in the heat storage medium circulation circuit in the sixth embodiment. This system can also store the cold in the heat storage tank by operating the high temperature side refrigeration cycle, and the condenser 7 in the second refrigeration cycle can be cooled using the cold.

The eighth embodiment is characterized in that a plurality of heat storage medium circulation circuits in the seventh embodiment are provided.
In the present invention, the high temperature side refrigeration cycle and the low temperature side refrigeration cycle are arranged by arranging a plurality of high temperature side refrigeration cycles in one heat storage tank and allowing a plurality of second refrigeration cycles to be cooled by a plurality of circulation circuits. Even in a distant position, it can be easily realized.

  The ninth embodiment is an improved version of the eighth embodiment and is characterized in that a load is provided in the heat storage medium circulation circuit 14 in the embodiment.

The tenth embodiment includes a first refrigeration cycle (hereinafter referred to as a high temperature side refrigeration cycle) S1 and a second refrigeration cycle (hereinafter referred to as a low temperature side refrigeration cycle) S2 of the heat storage type refrigeration system (including the refrigeration system) of the first embodiment. In the meantime, a brine pipe for storing the cold heat of the first refrigeration cycle in the heat storage tank via the brine solution is provided. That is, the heat from the first refrigeration cycle is not directly stored in the heat storage tank as in the first embodiment, but in the heat storage tank 5 by the refrigerant circulating in the brine pipe via the brine pipe on the way. It is characterized by storing cold energy.
Specifically, the high temperature side refrigeration cycle S1 includes a high temperature side condenser 1, a high temperature side compressor 2, a high temperature side evaporator 3, and a high temperature side expansion valve 4, as in the known refrigeration cycle, which are illustrated in the figure. Arranged so that they are connected. A brine pipe is disposed adjacent to the high temperature side evaporator, the brine in the brine pipe is cooled by the cold heat obtained by the high temperature side evaporator, and the cooling brine is circulated by a brine circulation pump to produce ice in the heat storage tank 5. The heat storage medium can be cooled via the coil.
The heat storage tank 5 has a function of storing cold heat given from an ice making coil of a brine pipe in a heat storage medium in the heat storage tank.

  The low temperature side refrigeration cycle S2 is a low temperature side condenser 7, a low temperature side compressor 8, a low temperature side load (evaporator) 11, a low temperature side expansion valve 9, and a low temperature side liquid receiver, which are conventionally known, like the high temperature side refrigeration cycle. And the like are arranged and connected as shown in the figure. In this example, carbon dioxide gas is used as the refrigerant for the low temperature side refrigeration cycle, but other refrigerants (ammonia, HC refrigerant, chlorofluorocarbon refrigerant, etc.) can also be used. The ice making coil in the brine pipe and the low temperature side condenser 7 of the low temperature refrigeration cycle S2 are immersed in a heat storage medium (brine, water, etc.) 6 that is housed in the heat storage tank 5 and stored in the heat storage tank 5. It has been.

The operation of the heat storage type refrigeration system having the above configuration will be described.
First, the cold heat is produced by operating the high-temperature side refrigeration cycle S1 prior to the cooling target load process (or simultaneous processing), and the cold heat is stored in the heat storage medium 6 of the heat storage tank 5 shown in FIG.
The low temperature refrigeration cycle S2 cools the refrigeration load existing in the low temperature region while using the cold energy stored in the heat storage tank 5 for condensation.
In the tenth embodiment, a plurality of high-temperature refrigeration cycles S1 and low-temperature refrigeration cycles S2 can be provided as in the second embodiment, or a load circuit and a load circulation circuit can be provided as in the third to fifth embodiments. is there.

  As mentioned above, although the Example of this invention was described, arrangement | positioning of an evaporator, a condenser, etc. in a thermal storage tank, arrangement | positioning of a refrigerating load circuit, etc. can be suitably changed within the range of the meaning of this invention. In addition, as the refrigerants for the first and second refrigeration cycles, various refrigerants that currently exist can be selectively used. Of course, the refrigeration cycle includes a refrigeration cycle. Moreover, one or more heat storage tanks can be provided corresponding to the installation location and system. Furthermore, the specifications described in the examples are merely examples in all respects and should not be interpreted in a limited manner.

  The present invention can be used for various freezing and refrigeration systems such as fresh fish stores and convenience stores.

DESCRIPTION OF SYMBOLS 1 High temperature side condenser 2 High temperature side compressor 3 High temperature side evaporator 4 High temperature side expansion valve 5 Heat storage tank 6 Heat storage medium 7 Low temperature side condenser 8 Low temperature side compressor 9 Low temperature side expansion valve 10 Low temperature side receiver 11 Refrigeration load (Low temperature side evaporator)
14 Heat storage medium circulation circuit 15a Load circuit 15 Load 16 Load circulation circuit 17a Heat storage medium circulation pump 17 CO2 circulation pump 18 Heat exchanger in heat storage tank

Claims (13)

A first refrigeration cycle having a high temperature side condenser 1 and a high temperature side evaporator 3;
A second refrigeration cycle having a low temperature side condenser 7 and a low temperature side evaporator 11;
One heat storage tank 5 for accommodating the high temperature side evaporator 3 of the first refrigeration cycle and the low temperature side condenser 7 of the second refrigeration cycle;
A heat storage medium 6 accommodated in the heat storage tank,
The heat storage medium in the heat storage tank is cooled by the high temperature side evaporator of the first refrigeration cycle to store cold heat, and the low temperature side condenser of the second refrigeration cycle is stored by the cold heat stored in the heat storage medium in the heat storage tank. Cool,
A heat storage type refrigeration system characterized in that the refrigerant of the second refrigeration cycle is condensed. A plurality of first refrigeration cycles and a plurality of second refrigeration cycles are prepared, and a plurality of high temperature side evaporators of the first refrigeration cycles and a plurality of low temperature side condensers of the second refrigeration cycles are arranged in one heat storage tank. The regenerative refrigeration system according to claim 1. The regenerative refrigeration system according to claim 1 or 2, wherein the refrigerant in the first refrigeration cycle is a natural refrigerant such as ammonia, and the refrigerant in the second refrigeration cycle is carbon dioxide. The heat storage refrigeration system according to any one of claims 1 to 3, further comprising a load circuit 15a for pumping a heat storage medium in the heat storage tank and operating a load 15. 4. A heat storage tank heat exchanger for exchanging heat with the heat storage medium in the heat storage tank and a load circulation circuit 16 having a load are provided, and a carbon dioxide refrigerant is circulated in the circulation circuit 16. The regenerative refrigerating system according to any one of the above. The heat storage refrigeration system according to claim 5, wherein a circulation pump is provided in series with the heat storage tank heat exchanger 18 in the load circulation circuit 16. The regenerative refrigeration system according to claim 5, wherein the refrigerant in the load circulation circuit is naturally circulated using gravity. A first refrigeration cycle having a high temperature side condenser 1 and a high temperature side evaporator 3;
A second refrigeration cycle having a low temperature side condenser 7 and a low temperature side evaporator 11;
One heat storage tank 5 accommodating the high-temperature side evaporator 3 of the first refrigeration cycle;
A heat storage medium 6 accommodated in the heat storage tank,
A heat storage medium circulation circuit 14 that pumps up the heat storage medium of the heat storage tank and cools the low-temperature side condenser of the second refrigeration cycle by the cold energy stored in the heat storage medium in the heat storage tank is provided,
The heat storage medium in the heat storage tank is cooled by the high temperature side evaporator of the first refrigeration cycle to store cold heat, and the condenser of the second refrigeration cycle is cooled by the heat storage medium circulation circuit 14. Refrigeration system. 9. The refrigerant of the first refrigeration cycle is a natural refrigerant such as ammonia, and the refrigerant of the second refrigeration cycle is one of carbon dioxide, ammonia, HC refrigerant, and chlorofluorocarbon refrigerant. Thermal storage refrigeration system. The heat storage refrigeration system according to claim 8 or 9, wherein a load is provided in the heat storage medium circulation circuit.   The heat storage refrigeration system according to claim 8 or 9, wherein a plurality of heat storage medium circulation circuits for pumping up the heat storage medium of the heat storage tank are provided.   The heat storage refrigeration system according to claim 11, wherein a load is provided in the plurality of heat storage medium circulation circuits. A first refrigeration cycle having a high temperature side condenser 1 and a high temperature side evaporator 3;
A second refrigeration cycle having a low temperature side condenser 7 and a low temperature side evaporator 11;
A brine pipe having a brine circulation pump and an ice making coil, and a brine pipe capable of exchanging heat with the high temperature side evaporator of the first refrigeration cycle;
One heat storage tank 5 that houses the ice making coil and the low temperature side condenser 7 of the second refrigeration cycle;
A heat storage medium 6 accommodated in the heat storage tank,
The brine is cooled by the high-temperature side evaporator of the first refrigeration cycle, and the cooled brine is passed through an ice making coil in a heat storage tank to cool the heat storage medium to store cold energy, and to the heat storage medium in the heat storage tank. The low-temperature side condenser of the second refrigeration cycle is cooled by the stored cold heat,
A regenerative refrigerating system, wherein the refrigerant of the second refrigeration cycle is condensed.

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