JP7411929B2 - Refrigeration equipment - Google Patents

Description

The present invention relates to a refrigeration system, and particularly to a refrigeration system that can recover exhaust heat by supplying hot water.

BACKGROUND ART Conventionally, for example, large stores such as supermarkets have been equipped with many frozen showcases and refrigerated showcases, and refrigeration systems that operate these showcases with refrigerators are often used.

Conventionally, in such a refrigeration system, for example, water pipes are connected in parallel to an intercooler and a gas cooler, and the cooling water supplied to each is used to exchange heat with the refrigerant discharged from the lower stage compression mechanism in the intercooler. A technique has been disclosed in which the refrigerant is exchanged with the refrigerant discharged from the high-stage compression mechanism in the gas cooler (for example, see Patent Document 1).

Patent No. 4947197

However, in the conventional technology, in order to increase the hot water supply temperature, it was necessary to reduce the flow rate of water flowing through the water pipes of the intercooler and gas cooler. Therefore, by reducing the flow rate of water, the heat exchange performance decreases, causing insufficient heat dissipation of the refrigerant in the intercooler and gas cooler, and the refrigerant temperature on the outlet side of the gas cooler increases, resulting in the refrigeration capacity of the refrigeration system being reduced. There was a problem that there was a shortage.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a refrigeration system that can efficiently cool a cooling device without causing insufficient refrigerating capacity even when the hot water temperature is increased. That is.

In order to achieve the above object, the present invention includes a low-stage compression mechanism, a high-stage compression mechanism, an expansion mechanism, an intercooler that cools refrigerant discharged from the low-stage compression mechanism, and a refrigerant discharged from the high-stage compression mechanism. A main gas cooler that cools the refrigerant and an auxiliary gas cooler that cools the refrigerant after passing through the main gas cooler, the refrigerant is cooled by heat exchange between the refrigerant and water, and a water flow path for cooling the refrigerant is provided. The refrigeration system is connected by water piping, and the water piping includes a first water piping, a first branch part that branches in the middle of the first water piping, a first merging part, and the first branch part. and the first merging section via the auxiliary gas cooler; and a second water pipe connecting the first branching section and the first merging section to the intercooler without merging with the second water piping. A fourth water pipe connects the first merging part and the main gas cooler, and a hot water supply pipe connects the main gas cooler and a hot water supply place . , a control unit, a water supply mechanism provided in the middle of the water pipe to control the flow rate, and an inlet side water temperature sensor provided in the first water pipe to detect the temperature of water entering the auxiliary gas cooler and the intercooler. , an outlet side water temperature sensor for detecting the outlet side water temperature of the main gas cooler provided in the hot water supply pipe; a refrigerant temperature sensor for measuring the temperature of the refrigerant that has passed through the auxiliary gas cooler; and a refrigerant temperature sensor provided in the fourth water pipe. and a first flow rate adjustment mechanism that adjusts the flow rate of water flowing into the main gas cooler and the drainage pipe, and the control unit controls the detection value of the inlet-side water temperature sensor and the refrigerant temperature sensor. It is characterized in that the water supply mechanism is controlled based on the detected value, and the first flow rate adjustment mechanism is controlled based on the detected value of the outlet side water temperature sensor .

According to this, by injecting water into the auxiliary gas cooler and the intercooler in parallel, the temperature of the auxiliary gas cooler outlet refrigerant and the intercooler outlet refrigerant can be cooled to around the inlet water temperature.

According to the present invention, by injecting water into the auxiliary gas cooler and the intercooler in parallel, the temperature of the auxiliary gas cooler outlet refrigerant and the intercooler outlet refrigerant can be cooled to around the inlet water temperature. As a result, since there is a main gas cooler and an auxiliary gas cooler, it is possible to sufficiently cool the refrigerant even with a small flow rate of water.

Refrigerant circuit diagram of a refrigeration system according to the first embodiment of the present invention Block diagram showing the control configuration of the first embodiment Flowchart showing the operation of the first embodiment Refrigerant circuit diagram of the refrigeration system according to the second embodiment

A first invention includes a low-stage compression mechanism, a high-stage compression mechanism, an expansion mechanism, an intercooler that cools the refrigerant discharged from the low-stage compression mechanism, and a main body that cools the refrigerant discharged from the high-stage compression mechanism. A gas cooler and an auxiliary gas cooler that cools the refrigerant after passing through the main gas cooler, the refrigerant is cooled by heat exchange between the refrigerant and water, and a water flow path for cooling the refrigerant is connected by water piping. In the refrigeration system, the water pipe includes a first water pipe, a first branch part that branches in the middle of the first water pipe, a first confluence part, and the first branch part and the first confluence part. a second water pipe that connects the first branching part and the first merging part via the intercooler without merging with the second water pipe; It is composed of a third water pipe, a fourth water pipe that connects the first merging section and the main gas cooler, and a hot water pipe that connects the main gas cooler and a hot water usage place, and the water pipe It has a water supply mechanism in the middle.
According to this, by injecting water into the auxiliary gas cooler and the intercooler in parallel, the temperature of the auxiliary gas cooler outlet refrigerant and the intercooler outlet refrigerant can be cooled to around the inlet water temperature. Since there is a main gas cooler and an auxiliary gas cooler, it is possible to sufficiently cool the refrigerant even with a small flow rate of water.

A second invention includes a water supply mechanism that controls the flow rate of the water pipe, a control section that controls the water supply mechanism, and an outlet side water temperature sensor that detects the water temperature on the outlet side of the main gas cooler provided in the hot water supply pipe. The control unit controls the water supply mechanism based on a value detected by the outlet water temperature sensor.
According to this, since the flow rate of water flowing through the water pipe can be adjusted by the water supply mechanism, the refrigerating capacity can be ensured while supplying hot water at a predetermined temperature.

A third invention includes a water inlet temperature sensor that is provided in the first water pipe and detects the temperature of water entering the auxiliary gas cooler and the intercooler, and a refrigerant temperature sensor that measures the temperature of the refrigerant that has passed through the auxiliary gas cooler. The controller includes a sensor, a drainage pipe provided in the fourth water pipe, and a first flow rate adjustment mechanism that adjusts the flow rate of water flowing to the main gas cooler and the drainage pipe, and the control unit controls the first flow rate. Control the adjustment mechanism.
According to this, by using the first flow rate adjustment mechanism, unnecessary water can be drained, thereby ensuring the flow rate of water flowing into the auxiliary gas cooler and intercooler while reducing the flow rate of water flowing into the main gas cooler. can. This makes it possible to heat water to the temperature of the refrigerant discharged from the high-stage compression mechanism and supply hot water while maintaining the refrigerating capacity.

In a fourth invention, the water supply mechanism is provided between the first merging section of the fourth water pipe and the first flow rate adjustment mechanism.
Thereby, since the water supply mechanism is provided in the fourth water pipe, the exhaust heat of the water supply mechanism can be used for hot water supply, and hot water supply can be performed more efficiently. Moreover, the water sent to the auxiliary gas cooler and intercooler is not heated by the water supply mechanism, and the temperature of the water entering the auxiliary gas cooler and intercooler can be lowered. This improves the efficiency of the compression mechanism and increases the refrigerating capacity.

A fifth aspect of the present invention is an external heat radiating device connected to the drainage pipe, a second merging section provided on the first water pipe, and a fifth radiating device connecting the external heat radiating device and the second merging section. Equipped with water piping.
According to this, the water flowing into the drainage pipe can be cooled in an external heat radiating device, and the cooled water is sent to the auxiliary gas cooler and intercooler via the water pipe, allowing the water to be reused without being disposed of. This makes it possible to operate the refrigeration system while reducing the amount of water used.

A sixth invention includes an internal heat exchanger provided between the auxiliary gas cooler and the expansion mechanism, a refrigerant branch section provided after passing through the internal heat exchanger, and an intake of the high-stage compression mechanism. a refrigerant confluence section provided on the side, a refrigerant return pipe connecting the refrigerant branch section and the refrigerant confluence section via the internal heat exchanger, and a refrigerant return pipe that connects the refrigerant branch section and the refrigerant confluence section via the internal heat exchanger; and a second expansion mechanism provided at.
According to this, the internal heat exchanger exchanges heat between the refrigerant sent from the auxiliary gas cooler and the refrigerant expanded by the second expansion mechanism via the refrigerant return pipe, thereby reducing the temperature of the refrigerant sent to the evaporator. refrigeration capacity can be increased. In addition, in the present invention, the temperature of the refrigerant at the outlet of the intercooler is reduced to near the inlet water temperature by parallel water injection, thereby reducing the suction refrigerant pressure of the high-stage compression mechanism, that is, the refrigerant pressure in the refrigerant return pipe after passing through the second expansion mechanism. However, the temperature of the refrigerant on the side cooled by the internal heat exchanger can be lowered. This allows the refrigeration capacity to be further increased.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a refrigerant circuit diagram showing a first embodiment of a refrigeration system according to the present invention.
As shown in FIG. 1, the refrigeration device 1 is connected to a cooling device that is cooled by a refrigerant sent from the refrigeration device 1, and the cooling device is installed in a facility such as a convenience store or a supermarket, for example. These are showcases that cool displayed refrigerated and frozen products.
Further, in the present embodiment, the refrigeration apparatus 1 uses carbon dioxide as a refrigerant in which the refrigerant pressure on the high pressure side (high pressure) is equal to or higher than the critical pressure (supercritical). This carbon dioxide refrigerant is a natural refrigerant that is environmentally friendly and takes into account flammability and toxicity.

The refrigeration system 1 includes a compressor 10. In this embodiment, the compressor 10 includes a two-stage compression mechanism, a low-stage compression mechanism 11 and a high-stage compression mechanism 12.
In this embodiment, the compressor 10 is equipped with a two-stage compression mechanism including the low-stage compression mechanism 11 and the high-stage compression mechanism 12, but the two compressors are provided as a low-stage compressor and a high-stage compression mechanism, respectively. Equivalent functionality can be obtained even when used as a stage side compressor.
The low stage compression mechanism 11 is provided with a low stage suction port 13 and a low stage discharge port 14, and the high stage compression mechanism 12 is provided with a high stage suction port 15 and a high stage discharge port 16.
The low-pressure refrigerant pipe 17 connected to the evaporator 40 of the cooling equipment is connected to the low-stage suction port 13, and the low-pressure refrigerant sent from the evaporator 40 of the cooling equipment via the low-pressure refrigerant pipe 17 is sucked into the low stage. It is sent to the low stage compression mechanism 11 through the port 13.

The low-stage compression mechanism 11 compresses the low-temperature, low-pressure refrigerant sucked in from the low-stage suction port 13 to raise the pressure to an intermediate pressure, and discharges the refrigerant from the low-stage discharge port 14 . The intermediate-pressure refrigerant compressed by the low-stage compression mechanism 11 is sucked in from the high-stage suction port 15 via the intermediate-pressure discharge pipe 18, intercooler 30, and intermediate-pressure suction pipe 19, and is compressed by the high-stage compression mechanism 12. It is configured to increase the pressure to a high pressure and discharge it from the high-stage discharge port 16.

An intermediate pressure discharge pipe 18 connected to the low stage compression mechanism 11 is connected to an inlet side 30a of one flow path of the intercooler 30.
An intermediate pressure suction pipe 19 is connected to the outlet side 30b of one flow path of the intercooler 30, and the intermediate pressure suction pipe 19 is connected to the high stage suction port 15 of the high stage compression mechanism 12.

Further, a high-pressure discharge pipe 20 is connected to the high-stage discharge port 16 of the high-stage compression mechanism 12, and the high-pressure discharge pipe 20 is connected to the inlet side 31a of one flow path of the main gas cooler 31. .
An outlet side 31 b of one flow path of the main gas cooler 31 is connected to an inlet side 32 a of one flow path of the auxiliary gas cooler 32 via a refrigerant pipe 21 . An outlet side 32b of one flow path of the auxiliary gas cooler 32 is connected to an expansion mechanism 41 of the cooling device via the refrigerant pipe 22. An evaporator 40 is connected to the expansion mechanism 41, and a low stage compression mechanism 11 is connected to the evaporator 40.

A water pipe 50 is connected to the other flow path of the auxiliary gas cooler 32, the main gas cooler 31, and the intercooler 30.
The water pipe 50 supports a first water pipe 51, a first branch part 52 branching in the middle of the first water pipe 51, a first merging part 53, and a first branch part 52 and a first merging part 53. A second water pipe 54 is connected via the inlet side 32c and outlet side 32d of the gas cooler 32, and the first branch part 52 and the first merging part 53 are connected to the intercooler 30 without merging with the second water pipe 54. a third water pipe 55 that connects via the inlet side 30c and outlet side 30d of the main gas cooler 31; The hot water supply pipe 57 connects the outlet side 31d of the hot water supply and the hot water supply destination.

As described above, in this embodiment, the water pipe 50 is connected in parallel to the auxiliary gas cooler 32 and the intercooler 30 by the second water pipe 54 and the third water pipe 55. The connected second water pipe 54 and third water pipe 55 are configured to be connected in series to the main gas cooler 31 via a fourth water pipe 56.

The first water pipe 51 of the water pipe 50 is provided with a water supply mechanism 60 such as a water supply pump, for example.
A first flow rate adjustment valve 61 as a first flow rate adjustment mechanism is provided in the middle of a fourth water pipe 56 that is connected to and merges with the outlet sides of the auxiliary gas cooler 32 and intercooler 30 . Drainage pipes 58 are connected to locations that are not connected to the water pipes 50.
In this embodiment, the first flow rate adjustment valve 61 is provided with a three-way valve, but the same function can be obtained even if two two-way valves are used as the first flow rate adjustment valve 61.

The refrigerant pipe 22 is provided with a refrigerant temperature sensor 71 that detects the refrigerant temperature on the outlet side of the auxiliary gas cooler 32. The first water pipe 51 is provided with an inlet water temperature sensor 72 that detects the temperature of water entering the auxiliary gas cooler 32 and the intercooler 30, and the hot water supply pipe 57 on the outlet side of the main gas cooler 31 is provided with an A side water temperature sensor 73 is provided.

FIG. 2 is a block diagram showing the control configuration of this embodiment.
As shown in FIG. 2, in this embodiment, the refrigeration apparatus 1 includes a control section 70 that centrally controls each section. The control unit 70 controls the drive of the compressor 10 and the opening degree of the expansion mechanism 41. Further, the control unit 70 is configured to control the driving of the water supply mechanism 60 and the first flow rate regulating valve 61 based on the values detected by the refrigerant temperature sensor 71, the inlet water temperature sensor 72, and the outlet water temperature sensor 73. There is.

Next, the operation of the first embodiment will be explained.
First, by operating the compressor 10, the low stage suction port 13 of the low stage compression mechanism 11 sucks refrigerant sent from the evaporator 40 of the cooling equipment. It is compressed to high pressure and discharged from the low stage discharge port 14.

Further, the refrigerant discharged from the low stage discharge port 14 of the low stage compression mechanism 11 flows into the intercooler 30 via the intermediate pressure discharge pipe 18. The inflowing refrigerant is cooled by heat exchange with water in the intercooler 30 and sent to the high stage suction port 15 of the high stage compression mechanism 12.
The refrigerant sent from the intercooler 30 is compressed by the high stage compression mechanism 12, discharged from the high stage discharge port 16, and sent to the main gas cooler 31.

The refrigerant sent from the high-stage compression mechanism 12 exchanges heat with water in the main gas cooler 31, then exchanges heat with the auxiliary gas cooler 32, and is sent to the evaporator 40 via the expansion mechanism 41.

Here, in this embodiment, water pipe 50 is connected in parallel to auxiliary gas cooler 32 and intercooler 30, and then connected in series to main gas cooler 31.
Therefore, water flowing through the water pipe 50 flows simultaneously to the auxiliary gas cooler 32 and the intercooler 30, and then flows to the main gas cooler 31.
Thereby, by injecting water into the auxiliary gas cooler 32 and the intercooler 30 in parallel, the temperature of the auxiliary gas cooler 32 outlet refrigerant and the intercooler 30 outlet refrigerant can be cooled to near the inlet water temperature.
Since there is a main gas cooler 31 and an auxiliary gas cooler 32, it is possible to sufficiently cool the refrigerant even with a small flow rate of water.

Further, since the flow rate of water flowing through the water pipe 50 can be adjusted by the water supply mechanism 60, the refrigerating capacity can be ensured while supplying hot water at a predetermined temperature.
By using the first flow rate adjustment valve 61, the amount of water that is unnecessary for supplying hot water at a predetermined temperature can be drained before it flows into the main gas cooler 31, so the flow rate of water flowing into the main gas cooler 31 It is possible to secure the flow rate of water flowing into the auxiliary gas cooler 32 and the intercooler 30 while reducing the amount of water. This makes it possible to heat the water to the temperature of the refrigerant discharged from the high-stage compression mechanism 12 and supply hot water while maintaining the refrigerating capacity.

Next, the control operation of the first embodiment will be explained.
FIG. 3 is a flowchart showing the operation of the first embodiment.
As shown in FIG. 3, when controlling the flow rate of water supply (hot water supply), the control unit 70 first sets the flow rate to an initial flow rate and starts operation (ST1).
Thereafter, the control unit 70 acquires the target hot water temperature setting value Tg, the current outlet water temperature Tout from the outlet water temperature sensor 73, the inlet water temperature Tin from the inlet water temperature sensor 72, and the refrigerant outlet temperature Tref from the refrigerant temperature sensor 71. (ST2).

The control unit 70 determines whether the refrigerant outlet temperature Tref is higher than the inlet water temperature Tin+Δtin1 (ST3).
If it is determined that the refrigerant outlet temperature Tref is higher than the inlet water temperature Tin+Δtin1 (ST3: YES), the water supply mechanism 60 is controlled to increase the flow rate. (ST4).
Then, the above-described control is continued until a flow rate control end signal is input (ST5: NO).

On the other hand, if it is determined that the refrigerant outlet temperature Tref is lower than the inlet water temperature Tin+Δtin1 (ST3: NO), the control unit 70 determines whether the refrigerant outlet temperature Tref is lower than the inlet water temperature Tin+Δtin2 (ST6).
If it is determined that the refrigerant outlet temperature Tref is lower than the inlet water temperature Tin+Δtin2 (ST6: YES), the control unit 70 controls the water supply mechanism 60 to reduce the flow rate (ST7). Thereafter, the above-described control is continued until a flow control end signal is input (ST5: NO).

If it is determined that the refrigerant outlet temperature Tref is higher than the inlet side water temperature Tin+Δtin2 (ST6: NO), the control unit 70 determines whether the outlet side water temperature Tout is higher than the target hot water supply temperature setting value Tg+Δtg (ST8).
Then, if it is determined that the outlet side water temperature Tout is higher than the target hot water supply temperature setting value Tg+Δtg (ST8: YES), the control unit 70 controls to increase the flow rate on the outlet side of the first flow rate adjustment valve 61 ( ST9). Thereafter, the above-described control is continued until a flow control end signal is input (ST5: NO).

If it is determined that the outlet side water temperature Tout is lower than the target hot water supply temperature setting value Tg+Δtg (ST8: NO), the control unit 70 determines whether the outlet side water temperature Tout is lower than the target hot water supply temperature setting value Tg−Δtg. Make a judgment (ST10).
If it is determined that the outlet side water temperature Tout is lower than the target hot water supply temperature setting value Tg-Δtg (ST10: YES), the control unit 70 controls the flow rate on the outlet side of the first flow rate adjustment valve 61 to decrease ( ST11).

If it is determined that the outlet side water temperature Tout is higher than the target hot water supply temperature set value Tg-Δtg (ST10: NO), the above-described control is continued until a flow control end signal is input (ST5: NO).
Thereafter, when a flow control end signal is input (ST5: YES), the flow control is ended.

As described above, according to the first embodiment, the intercooler 30 that cools the refrigerant discharged from the low stage compression mechanism 11, the main gas cooler 31 that cools the refrigerant discharged from the high stage compression mechanism 12, and the main gas cooler 31 that cools the refrigerant discharged from the high stage compression mechanism 12, an auxiliary gas cooler 32 that cools the refrigerant after passing through the gas cooler 31; A confluence section 53, a second water pipe 54 that connects the first branch section 52 and the first confluence section 53 via the auxiliary gas cooler 32, and a second water pipe 54 that connects the first branch section 52 and the first confluence section 53 via the auxiliary gas cooler 32; and the first confluence section 53 via the intercooler 30, the fourth water conduit 56 that connects the first confluence section 53 and the main gas cooler 31, and the main gas cooler 31 and the hot water supply. It is composed of a hot water supply pipe 57 that connects to a user, and a water supply mechanism 60 is provided in the middle of the water pipe 50.
According to this, by injecting water into the auxiliary gas cooler 32 and the intercooler 30 in parallel, the temperature of the auxiliary gas cooler 32 outlet refrigerant and the intercooler 30 outlet refrigerant can be cooled to around the inlet water temperature. Furthermore, since there is the main gas cooler 31 and the auxiliary gas cooler 32, it is possible to sufficiently cool the refrigerant even with a small flow rate of water.

In addition, in this embodiment, a water supply mechanism 60 that controls the flow rate of the water pipe 50, a control section 70 that controls the water supply mechanism 60, and an outlet side that detects the water temperature on the outlet side of the hot water supply pipe 57 of the main gas cooler 31 are provided. A water temperature sensor 73 is provided, and the control unit 70 controls the water supply mechanism 60 based on the detected value by the outlet side water temperature sensor 73.
According to this, the flow rate flowing through the water pipe 50 can be adjusted by the water supply mechanism 60, and the refrigerating capacity can be ensured while supplying hot water at a predetermined temperature.

In addition, in this embodiment, a water inlet temperature sensor is provided in the first water pipe 51 to detect the temperature of water entering the auxiliary gas cooler 32 and the intercooler 30, and a water inlet temperature sensor that measures the temperature of the refrigerant that has passed through the auxiliary gas cooler 32. The control unit 70 includes a refrigerant temperature sensor 71 that controls the flow rate, a drain pipe 58 provided in the fourth water pipe 56, and a first flow rate adjustment valve 61 that adjusts the flow rate of water flowing into the main gas cooler 31 and the drain pipe 58. controls the first flow rate regulating valve 61.
According to this, by using the first flow rate regulating valve 61, it is possible to drain an amount of water that is unnecessary for supplying hot water at a predetermined temperature, so while reducing the flow rate of water flowing into the main gas cooler 31, The flow rate of water flowing into the auxiliary gas cooler 32 and intercooler 30 can be ensured. This makes it possible to heat the water to the temperature of the refrigerant discharged from the high-stage compression mechanism 12 and supply hot water while maintaining the refrigerating capacity.

Next, a second embodiment of the present invention will be described.
FIG. 4 is a refrigerant circuit diagram of a refrigeration system showing a second embodiment of the present invention.
As shown in FIG. 4, in this embodiment, the water supply mechanism 60 is provided between the first merging section 53 of the fourth water pipe 56 and the first flow rate regulating valve 61.
Further, an external heat radiating device 80 is connected to the drain pipe 58, and the external heat radiating device 80 merges into a second merging section 82 provided on the first water pipe 51 via a fifth water pipe 81. ing.

Further, an internal heat exchanger 83 is provided between the auxiliary gas cooler 32 and the expansion mechanism 41. A refrigerant branch section 84 is provided on the downstream side of the internal heat exchanger 83, and a refrigerant merging section 85 is provided on the suction side of the high-stage compression mechanism 12. Refrigerant return pipes 86a and 86b are provided to connect the refrigerant branch part 84, the internal heat exchanger 83, and the refrigerant merging part 85. A mechanism 87 is provided.
The other configurations are the same as those in the first embodiment, so the same parts are given the same reference numerals and the explanation thereof will be omitted.
Further, since the control of the water supply mechanism 60 and the first flow rate regulating valve 61 is the same as that of the first embodiment, the explanation thereof will be omitted.

In this embodiment, since the water supply mechanism 60 is provided in the fourth water pipe 56, the exhaust heat of the water supply mechanism 60 can be used for hot water supply, and hot water can be supplied more efficiently.
Further, the water sent to the auxiliary gas cooler 32 and the intercooler 30 is not heated by the water feeding mechanism 60, and the temperature of the water entering the auxiliary gas cooler 32 and the intercooler 30 can be lowered. This improves the efficiency of the compression mechanism and increases the refrigerating capacity. Furthermore, a portion of the heat radiated by the water supply mechanism 60 can be used to raise the temperature of the water entering the main gas cooler 31, so that the hot water temperature can be efficiently raised to a predetermined temperature.

Further, in this embodiment, water flowing from the fourth water pipe 56 to the drain pipe 58 via the first flow rate regulating valve 61 is sent to the external heat radiating device 80 and cooled therein.
This cooled water is sent to the auxiliary gas cooler 32 and the intercooler 30 via the fifth water pipe 81, the first water pipe 51, the second water pipe 54, and the third water pipe 55, respectively. Thereby, water can be reused without being disposed of, and the refrigeration apparatus 1 can be operated with less water used.

In addition, the internal heat exchanger 83 exchanges heat between the refrigerant sent from the auxiliary gas cooler 32 and the refrigerant expanded by the second expansion mechanism 87 via the refrigerant return pipe 86a, thereby increasing the temperature of the refrigerant sent to the evaporator 40. can be lowered and the refrigeration capacity can be increased.
Furthermore, in this embodiment, the temperature of the outlet refrigerant of the intercooler 30 is reduced to near the inlet water temperature by parallel water injection, so that the suction refrigerant pressure of the high-stage compression mechanism 12, that is, the refrigerant return pipe 86a after passing through the second expansion mechanism 87, is reduced. , 86b decreases, and the temperature of the refrigerant cooled by the internal heat exchanger 83 can be lowered. Thereby, the refrigeration capacity can be further increased.

As described above, in this embodiment, the water supply mechanism 60 is provided between the first merging section 53 of the fourth water pipe 56 and the first flow rate regulating valve 61.
According to this, since the water supply mechanism 60 is provided in the fourth water pipe 56, the exhaust heat of the water supply mechanism 60 can be used for hot water supply, and hot water can be supplied more efficiently.
Further, the water sent to the auxiliary gas cooler 32 and the intercooler 30 is not heated by the water feeding mechanism 60, and the temperature of the water entering the auxiliary gas cooler 32 and the intercooler 30 can be lowered. This improves the efficiency of the compressor 10 and increases the refrigerating capacity.

Further, in the present embodiment, an external heat radiating device 80 connected to the drainage pipe 58, a second confluence section 82 provided on the first water pipe 51, and an external heat dissipating device 80 and the second confluence section 82 are connected to each other. A fifth water pipe 81 is provided.
According to this, by providing the external heat radiating device 80, the water cooled by the external heat radiating device 80 can be sent to the auxiliary gas cooler 32 and the intercooler 30, and the water can be reused without being disposed of. It becomes possible to operate the refrigeration system 1 while reducing the amount of water used.

Further, in this embodiment, an internal heat exchanger 83 provided between the auxiliary gas cooler 32 and the expansion mechanism 41, a refrigerant branch section 84 provided after passing through the internal heat exchanger 83, and a high stage A refrigerant confluence section 85 provided on the suction side of the compression mechanism 12, refrigerant return pipes 86a and 86b connecting the refrigerant branch section 84 and the refrigerant confluence section 85 via the internal heat exchanger 83, and refrigerant return pipes 86a and 86a on the refrigerant return pipe 86a. and a second expansion mechanism 87 provided before flowing into the internal heat exchanger 83.
According to this, by exchanging heat with the internal heat exchanger 83, the temperature of the refrigerant sent to the evaporator 40 can be lowered, and the refrigerating capacity can be increased. In addition, the temperature of the outlet refrigerant of the intercooler 30 decreases to near the inlet water temperature due to the parallel water injection, thereby increasing the suction refrigerant pressure of the high stage compression mechanism 12, that is, the refrigerant pressure in the refrigerant return pipes 86a, 86b after passing through the second expansion mechanism 87. The temperature of the refrigerant cooled by the internal heat exchanger 83 can be lowered. Thereby, the refrigeration capacity can be further increased.

Note that the present invention is not limited to the embodiments described above, and various changes can be made without departing from the spirit of the present invention.

As described above, the refrigeration system according to the present invention can be suitably used as a refrigeration system that can maintain refrigerating capacity even when the hot water supply temperature is increased. Furthermore, the refrigeration device according to the present invention exchanges heat between a refrigerant and water, and can be suitably used for hot water supply using the hot water generated by heat exchange, hot water supply for hot water heating, and hot water heating equipment. It is possible.

1 Refrigeration equipment 10 Compressor 11 Low stage compression mechanism 12 High stage compression mechanism 13 Low stage suction port 14 Low stage discharge port 15 High stage suction port 16 High stage discharge port 17 Low pressure refrigerant pipe 18 Intermediate pressure discharge pipe 19 Intermediate pressure suction pipe 20 High pressure discharge pipe 21 Refrigerant pipe 22 Refrigerant pipe 30 Intercooler 31 Main gas cooler 32 Auxiliary gas cooler 40 Evaporator 41 Expansion mechanism 50 Water pipe 51 First water pipe 52 First branch part 53 First confluence part 54 Second water pipe 55 3rd water pipe 56 4th water pipe 57 Hot water pipe 58 Drainage pipe 60 Water supply mechanism 61 1st flow rate adjustment valve 70 Control part 71 Refrigerant temperature sensor 72 Inlet side water temperature sensor 73 Outlet side water temperature sensor 80 External heat radiation device 81 5th water pipe 82 Second confluence section 83 Internal heat exchanger 84 Refrigerant branch section 85 Refrigerant confluence section 86a, 86b Refrigerant return pipe 87 Second expansion mechanism

Claims (4)

a low-stage compression mechanism, a high-stage compression mechanism, an expansion mechanism, an intercooler that cools the refrigerant discharged from the low-stage compression mechanism, a main gas cooler that cools the refrigerant discharged from the high-stage compression mechanism, and the main gas cooler that cools the refrigerant discharged from the high-stage compression mechanism. An auxiliary gas cooler that cools the refrigerant after passing through the gas cooler, the refrigerant is cooled by heat exchange between the refrigerant and water, and a water flow path for cooling the refrigerant is connected by water piping. ,
The water piping is
A first water pipe,
a first branch part that branches in the middle of the first water pipe;
A first confluence part,
a second water pipe connecting the first branch part and the first merging part via the auxiliary gas cooler;
a third water pipe that connects the first branch part and the first merging part via the intercooler without merging with the second water pipe;
a fourth water pipe connecting the first confluence section and the main gas cooler;
Consisting of a hot water supply pipe that connects the main gas cooler and a hot water usage place,
a control unit;
a water supply mechanism that is installed in the middle of the water pipe and controls the flow rate;
an inlet-side water temperature sensor that is provided on the first water pipe and detects the temperature of water entering the auxiliary gas cooler and the intercooler;
an outlet side water temperature sensor that detects the outlet side water temperature of the main gas cooler provided in the hot water supply pipe;
a refrigerant temperature sensor that measures the temperature of the refrigerant that has passed through the auxiliary gas cooler;
a drainage pipe provided in the fourth water pipe;
A first flow rate adjustment mechanism that adjusts the flow rate of water flowing into the main gas cooler and the drainage pipe,
The control unit controls the water supply mechanism based on the detected value of the inlet side water temperature sensor and the detected value of the refrigerant temperature sensor, and controls the first flow rate adjustment mechanism based on the detected value of the outlet side water temperature sensor. A refrigeration device characterized by : The refrigeration system according to claim 1 , wherein the water supply mechanism is provided between the first merging section of the fourth water pipe and the first flow rate adjustment mechanism . an external heat radiator connected to the drainage pipe;
a second confluence section provided on the first water pipe;
The refrigeration system according to claim 2, further comprising a fifth water pipe connecting the external heat radiating device and the second merging section. an internal heat exchanger provided between the auxiliary gas cooler and the expansion mechanism;
a refrigerant branch provided after passing through the internal heat exchanger;
a refrigerant confluence section provided on the suction side of the high-stage compression mechanism;
a refrigerant return pipe connecting the refrigerant branch section and the refrigerant confluence section via the internal heat exchanger;
The refrigeration system according to claim 3 , further comprising a second expansion mechanism provided on the refrigerant return pipe before the refrigerant flows into the internal heat exchanger .

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