JPH04260757A - Freezing cycle device - Google Patents

Abstract

PURPOSE:To ensure higher temperature with a condenser and lower temperature with an evaporator in highly effective operation separating a higher stage high boiling point refrigerant and a lower stage low boiling point refrigerant without use of a heat exchanger intermediate of a multiple system freezing cycle device, and lowering suction and discharge temperature of the high stage compressor and operating a title device in a low compression ratio of the two compressors CONSTITUTION:There are coupled in succession a first compressor 1, a rectification separator 2, a second compressor 3 connected to the bottom of the rectification separator 2, a condenser 4, a main pressure reducer 6, and an evaporator 7, etc. Further, an outlet pipe 5 of the condenser 4 is bypassed and connected to the bottom of the rectification separator 2 after passage through the first pressure reducer device 9 and the top of the rectification separator 2 is connected to the outlet pipe 5 of the main pressure reducer device 6 after passage through the second pressure reducer device 11. Finally, a non-azeotropic mixture refrigerant of the low boiling point refrigerant and the high boiling point refrigerant is encapsulated.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to refrigeration cycle devices for obtaining higher or lower temperatures, such as air conditioning, hot water supply, or ultra-low temperature devices.

0002

2. Description of the Related Art In recent years, refrigeration cycle devices have been required to be able to operate at higher temperatures or lower temperatures.

[0003] Conventionally, this type of refrigeration cycle device
A multi-component refrigeration cycle device in which a plurality of refrigeration cycle devices are connected in a cascade manner is known. In this multicomponent refrigeration cycle device, a refrigerant component with a high boiling point (hereinafter referred to as a high-boiling point refrigerant) is usually sealed in a high-stage refrigeration cycle, and a refrigerant component with a low boiling point (hereinafter referred to as a low-boiling point refrigerant) is enclosed in a low-stage refrigeration cycle. It was configured to include an intermediate heat exchanger that exchanges heat between the evaporative refrigerant in the higher stage and the condensed refrigerant in the lower stage.

[0004] In such a refrigeration cycle device, since a high boiling point refrigerant is sealed in the high stage refrigeration cycle, a high temperature can be obtained while lowering the vapor pressure in the high stage condenser. Since the cycle is filled with a low boiling point refrigerant, low temperatures can be obtained without creating negative pressure in the low stage evaporator.

[0005]

[Problems to be Solved by the Invention] Such conventional refrigeration cycle devices are suitable for the purpose of obtaining higher or lower temperatures; In order to separate the low boiling point refrigerant sealed in the cycle, the evaporating refrigerant in the high stage and the condensing refrigerant in the low stage exchange heat, and as a result, the evaporation temperature in the high stage is lower than the condensing temperature in the lower stage. The compressors disposed in each of the high-stage and low-stage refrigeration cycles are operated at high compression ratios, resulting in a problem of poor efficiency.

[0006]Furthermore, recent usage patterns of refrigeration cycle equipment include not only single-function usage such as high-temperature hot water supply equipment and ultra-low temperature equipment, but also multi-purpose usage such as dual use of high-temperature hot water supply and cooling/heating. There is. At this time, in multi-component refrigeration cycle equipment, it is possible to perform both hot water supply and heating functions in the high-stage condenser, but the heating capacity of high-boiling point refrigerants is low, so the equipment must be large-scale. There was a problem.

The present invention solves the above-mentioned problems by separating the high-boiling point refrigerant in the upper stage and the low-boiling point refrigerant in the lower stage without using a heat exchanger in the intermediate section, and in addition, the suction and the low-boiling point refrigerant in the high stage compressor. The first objective is to be able to operate the two compressors at a low compression ratio while lowering the discharge temperature, and to operate with high efficiency, making it possible to obtain a higher temperature in the condenser and a lower temperature in the evaporator. The purpose is to

[0008] A second objective is to mix the high-boiling point refrigerant in the high stage and the low-boiling point refrigerant in the low stage, and to be able to control the composition of the refrigerant so as to increase the heating capacity in the high stage condenser.
The purpose is to

[0009]

[Means for Solving the Problems] In order to achieve the first object, the present invention provides a first compressor, a rectification separator, a second compressor connected to the bottom of the rectification separator, a condenser, main pressure reducer,
The evaporator etc. are connected in sequence, the outlet pipe of the condenser is bypassed and the bottom part of the rectification separator is connected via a first pressure reduction device, and the top part of the rectification separator is connected to the bottom part of the rectification separator via a second pressure reduction device. The first means for solving the problem is that the refrigerant is connected to the outlet pipe of the main pressure reducing device and a non-azeotropic mixed refrigerant consisting of a low boiling point refrigerant and a high boiling point refrigerant is sealed.

[0010] In order to achieve the second object, a second means for solving the problem is to make the first pressure reducing device or the second pressure reducing device of the first problem solving means closable.

[0011]

[Operation] The present invention has the above-mentioned first problem solving means.
Separation of the non-azeotropic refrigerant mixture takes place inside the rectification separator.
At the top, the low-boiling refrigerant is concentrated, and at the bottom, the high-boiling refrigerant is concentrated. Therefore, the suction temperature of the second compressor connected to the bottom of the rectification separator is low, and the second compressor, condenser,
The first pressure reducing device, the second refrigeration cycle connected to the bottom of the rectification separator, and the circuit from the condenser outlet pipe to the confluence of the main pressure reducing device outlet pipe and the second pressure reducing device outlet pipe are concentrated. The high boiling point refrigerant is circulated. In addition, from the top of the rectification separator where the low boiling point refrigerant is concentrated, it passes through the second pressure reducing device and is mixed with the high boiling point refrigerant from the main pressure reducing device at the outlet pipe of the main pressure reducing device. A non-azeotropic mixed refrigerant having a mixed composition containing more low-boiling point components than the second refrigeration cycle circulates in the first refrigeration cycle connected to the refrigeration system and the rectification separator. The non-azeotropic mixed refrigerant having the composition thus mixed undergoes separation again inside the rectification separator, with the low boiling point refrigerant being concentrated at the top and the high boiling point refrigerant being concentrated at the bottom.

[0012] Therefore, unlike the conventional multicomponent refrigeration cycle equipment, there is no need for an intermediate heat exchanger, and the first heat exchanger is not required.
Not only can the refrigerant be separated into a low boiling point refrigerant in the second refrigeration cycle and a high boiling point refrigerant in the second refrigeration cycle, but also
The two compressors can be operated at a low compression ratio while reducing the suction and discharge temperatures of the compressors, allowing high efficiency operation to obtain higher temperatures in the condenser and lower temperatures in the evaporator. The refrigerant components and vapor pressure after such separation can be arbitrarily selected depending on the combination and composition of the non-azeotropic mixed refrigerant initially sealed, the pressure setting by each pressure reducing device, etc.

[0013] The second problem-solving means also provides a circuit that bypasses the outlet pipe of the condenser and is connected to the bottom of the rectification separator via the first pressure reducing device, and a circuit that connects the top of the rectification separator to the second By closing the circuit connected to the outlet pipe of the main pressure reducing device via the pressure reducing device, separation inside the rectification separator will also be stopped.
The enclosed non-azeotropic mixed refrigerant is circulated through the first compressor, the rectification separator, the second compressor connected to the bottom of the rectification separator, the condenser, the main pressure reducing device, and the evaporator, and is separated. Since the non-azeotropic refrigerant mixture containing more low-boiling point components than in the case of heating is condensed in the condenser, the heating capacity can be increased.

[0014]

Embodiment An embodiment of the present invention will be described below with reference to FIG.

As shown in the figure, the discharge pipe of the first compressor 1 is connected to the middle part of the rectification separator 2. The second compressor 3 is connected to the bottom of the rectification separator 2. The condenser 4 is connected to the second compressor 3 and its outlet pipe 5 is connected to the main pressure reducing device 6 . The evaporator 7 is connected to the main pressure reducing device 6, and this evaporator 7
The outlet pipe is connected to the first compressor 1. Further, an outlet bypass pipe 8 that bypasses the outlet pipe 5 of the condenser 4 is connected to the bottom of the rectification separator 2 via a first pressure reducing device 9,
The top of the rectification separator 2 is connected to a second pressure reducing device 11 by a pipe 10.
It is connected to the outlet pipe 5 of the main pressure reducing device 6 via. Therefore, the evaporator 7 and the first compressor 1 are also connected. The reservoir 12 is provided at the bottom of the rectification separator 2,
The discharge pipe of the first compressor 1 is connected to the middle part of the rectification separator 2 via a heat exchanger 13 provided inside the reservoir 12. The top of the rectification separator 2 constitutes a circulation circuit before being connected to the piping 10, and a cooler 14 is disposed within this circulation circuit. It consists of Furthermore, a first pressure reduction device 9 arranged in the outlet bypass pipe 8 of the condenser 4 or a second pressure reduction device 11 arranged in the pipe 10 from the top of the rectification separator 2 is a respective closable expansion valve. It is composed of The refrigeration cycle device is sealed with a non-azeotropic mixed refrigerant consisting of a low boiling point refrigerant and a high boiling point refrigerant.

To explain the operation in the above configuration, inside the rectification separator 2, the gas refrigerant supplied from the discharge pipe of the first compressor 1 passes through the heat exchanger 13 provided inside the reservoir 12.
The two-phase refrigerant is partially liquefied via the gas refrigerant supplied from the discharge pipe of the first compressor
The gas refrigerant in the reservoir 12 provided at the bottom of the rectification separator 2 is heated and vaporized through the gas refrigerant 3, and the gas refrigerant is liquefied by the cooler 14 in the circulation circuit at the top of the rectification separator 2 before being connected to the piping 10. The liquid refrigerant that is then returned to the top of the rectification separator 2 causes separation of the non-azeotropic mixed refrigerant by rectification, and the low boiling point refrigerant is concentrated at the top, and the high boiling point refrigerant is concentrated at the bottom. Therefore, since the second compressor 3 connected to the bottom of the rectification separator 2 sucks almost saturated gas refrigerant, its suction temperature is low, and the second compressor 3, condenser 4,
An outlet bypass pipe 8, a first pressure reducing device 9, a second refrigeration cycle connected to the bottom of the rectification separator 2, and a second pressure reducing device from the outlet pipe 5 of the condenser 4 to the outlet pipe 5 of the main pressure reducing device 6. A concentrated high-boiling refrigerant is circulated in the circuit up to the confluence of the 11 outlet pipes. In addition, since the top of the rectification separator 2 where the low boiling point refrigerant is concentrated is connected to the outlet pipe 5 of the main pressure reduction device 6 via the second pressure reduction device 11 via a pipe 10, the connected main mixed with the high boiling point refrigerant from the pressure reducing device 6;
A first unit connected to an evaporator 7, a first compressor 1, and a rectification separator 2
In the refrigeration cycle, a non-azeotropic mixed refrigerant having a mixed composition containing more low-boiling point components than in the second refrigeration cycle is circulated. The non-azeotropic mixed refrigerant composition mixed in this way is
Separation takes place again inside the rectification separator 2, with the low-boiling refrigerant being concentrated at the top and the high-boiling refrigerant being concentrated at the bottom.

[0017] Therefore, unlike the conventional multicomponent refrigeration cycle equipment, there is no need for an intermediate heat exchanger, and the second heat exchanger is not required.
Not only can the refrigerant in the second refrigeration cycle be separated into a high boiling point refrigerant in the first refrigeration cycle and a non-azeotropic mixed refrigerant having a composition containing more low boiling point components than in the second refrigeration cycle, but also in the second compressor 3. The discharge pressure of the first compressor 1 and the suction pressure of the second compressor 3 become almost the same while the suction and discharge temperatures of This enables highly efficient operation, and the condenser 4 in the second refrigeration cycle
It is possible to obtain high temperatures while lowering the vapor pressure at
A low temperature can be obtained without creating a negative pressure in the evaporator 7 in the first refrigeration cycle. Note that the refrigerant components and vapor pressure after such separation depend on the combination and composition of the non-azeotropic mixed refrigerant initially sealed, and the pressure settings by the main pressure reducing device 6, first pressure reducing device 9, and second pressure reducing device 11. The operating pressure for separation of the rectification separator 2 is at almost the same pressure level as the discharge pressure of the first compressor 1 and the suction pressure of the second compressor 3. This is made possible by configuring the entire refrigeration cycle as described above.

Furthermore, if the first pressure reducing device 9 disposed in the outlet bypass pipe 8 of the condenser 4 and the second pressure reducing device 11 disposed in the pipe 10 from the top of the rectification separator 2 are closed, the refinery Separation inside the distillation separator 2 is also stopped, and the enclosed non-azeotropic mixed refrigerant is transferred to the bottom of the first compressor 1, the heat exchanger 13, the rectification separator 2, and the rectification separator 2. A connected second compressor 3, a condenser 4, an outlet pipe 5 of the condenser 4, a main pressure reducing device 6,
Since the non-azeotropic mixed refrigerant that circulates through the evaporator 7 and has more low boiling point components than when separated is condensed in the condenser 4, the heating capacity can be increased. It also becomes possible to control the composition of the refrigerant.

In the above embodiment, the discharge pipe of the first compressor 1 is connected to the middle part of the rectification separator 2, but the connection position of the discharge pipe of the rectification separator 2 and the first compressor 1 is is rectification separator 2
The heating source of the heat exchanger 13 and the cold source of the cooler 14 are additional means for promoting separation by the two-phase refrigerant supplied from the first compressor 1. Other means may be used if available. Although the present invention has been described as an example of a basic refrigeration cycle device, it goes without saying that it may be applied to air conditioning, hot water supply, ultra-low temperature devices, and the like.

[0020]

As is clear from the above embodiments, according to the present invention, a first compressor, a rectification separator, a second compressor connected to the bottom of the rectification separator, a condenser, and a main pressure reducing device are provided. , an evaporator, etc., are connected to the bottom of the rectification separator via a first pressure reduction device by bypassing the outlet pipe of the condenser, and the top of the rectification separator is connected to the bottom of the rectification separator via a second pressure reduction device. Since the non-azeotropic mixed refrigerant consisting of a low-boiling point refrigerant and a high-boiling point refrigerant is sealed inside the rectification separator, the non-azeotropic mixed refrigerant is separated, and at the top, it is connected to the outlet pipe of the main pressure reducing device. The low boiling point refrigerant is concentrated, the high boiling point refrigerant is concentrated at the bottom, the concentrated high boiling point refrigerant is circulated in the condenser, and the low boiling point refrigerant is circulated in the evaporator, similar to the traditional multi-component refrigeration cycle equipment. The suction and discharge temperatures of the second compressor can be lowered while eliminating the need for a heat exchanger in the intermediate section, and high-efficiency operation allows higher temperatures in the condenser and lower temperatures in the evaporator to be obtained.

[0021] Alternatively, the outlet pipe of the condenser may be bypassed and the first
In a circuit that is connected to the bottom of the rectification separator via a pressure reduction device, or in a circuit that connects the top of the rectification separator to the outlet pipe of the main pressure reduction device via a second pressure reduction device, the first pressure reduction device or By closing the second pressure reducing device, separation inside the rectification separator can also be stopped, and the non-azeotropic mixed refrigerant with the enclosed composition can be transferred to the first compressor, the rectification separator, and the rectification separator. It circulates through the second compressor connected to the bottom of the separator, the condenser, the main pressure reducing device, and the evaporator, and the non-azeotropic refrigerant mixture, which has more low-boiling point components than during separation, condenses in the condenser, increasing the heating capacity. It is also possible to control the composition of the refrigerant.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a refrigeration cycle device according to an embodiment of the present invention.

[Explanation of symbols]

1 First compressor 2 Rectification separator 3 Second compressor 4 Condenser 5 Outlet pipe 6　Main pressure reducing device 7 Evaporator 9 First pressure reducing device 11 Second pressure reducing device

Claims (2)

[Claims] Claim 1: A first compressor, a rectification separator, a second compressor connected to the bottom of the rectification separator, a condenser, a main pressure reducing device, an evaporator, etc. are connected in order, and an outlet pipe of the condenser is connected in sequence. is bypassed and connected to the bottom of the rectification separator via a first pressure reduction device, and the top of the rectification separator is connected to the outlet pipe of the main pressure reduction device via a second pressure reduction device. A refrigeration cycle device containing a non-azeotropic mixed refrigerant consisting of a high boiling point refrigerant and a high boiling point refrigerant. 2. The refrigeration cycle device according to claim 1, wherein the first pressure reducing device or the second pressure reducing device can be closed.