JPH0246863B2 - REITOSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a compression type refrigeration system using a non-azeotropic refrigerant mixture to obtain a lower temperature.

Configuration of a conventional example and its problems FIG. 1 is a circuit configuration diagram of a refrigeration system using a conventional non-azeotropic mixed refrigerant. In FIG. 1, 1 is a compressor, 2 is a condenser, 3 is a gas-liquid separator, 4 and 5
6 is a heat exchanger, and 7 is an evaporator.
The operation of the refrigeration system configured as described above will be explained. First, the refrigerant vapor compressed by the compressor 1 is partially condensed by the condenser 2, and separated by the gas-liquid separator 3 into vapor containing a large amount of low-boiling point components and liquid containing a large amount of high-boiling point components in the mixed refrigerant. Ru. This liquid is expanded by the expansion device 4 and evaporated in the heat exchanger 6 to generate cooling, and the vapor separated by the gas-liquid separator 3 is condensed. This condensed liquid is expanded by the expansion device 5 and evaporated in the evaporator 7 to generate a low temperature.

However, in order to obtain a lower temperature in the evaporator 7, it is necessary to increase the composition of low boiling point components in the vapor separated by the gas-liquid separator 3, but in the above configuration, the temperature inside the gas-liquid separator 3 Only compositions that are balanced with pressure can be obtained. Therefore, it is known to connect several sets of gas-liquid separators and partial condensers in series to increase the composition of low-boiling components in the steam, but this requires complicated equipment and expensive gas-liquid separators and heat exchangers. There was a problem in that the cost was high because a large amount was required.

Furthermore, the current situation is that various measures are required to control the capacity of refrigeration equipment, and this is also one of the difficult problems to be solved.

Purpose of the Invention The present invention provides a rectification column to increase the separation effect of mixed refrigerant components and obtain a lower temperature with a simple configuration, and controls the capacity of a refrigeration system by adjusting the amount of refrigerant circulated to this rectification column. The purpose of this invention is to facilitate the above-mentioned problems and to solve the problems mentioned above.

Structure of the Invention As a structure for achieving this object, the present invention uses a non-azeotropic mixed refrigerant, includes a compressor, a condenser, a rectification column, an overhead condenser provided at the top of the rectification column, and a 1
A flow control valve, a first throttling device, and an evaporator are connected in a ring, and after being liquefied in the top condenser, it is separated into two circuits, one of which is returned to the top of the rectification column,
The other side is connected to the evaporator via a first flow rate control valve and a first throttle device, and after being evaporated in a reheater provided with the rectification column at the bottom, it is separated into two circuits, one of which is connected to the rectification column. The other circuit is connected to the compressor via a second flow control valve and a second throttle device,
A capacity controller is provided for controlling the first flow rate control valve or the first flow rate control valve and the second flow rate control valve to perform capacity control.

DESCRIPTION OF EMBODIMENTS FIG. 2 is a circuit diagram of an embodiment of the refrigeration system of the present invention. In FIG. 2, 8 is a compressor, 9 is a condenser, 10 is a rectification column, 11 is a reheater,
12 is a tower top condenser, 13 is a first flow rate control valve, 14
15 is a first throttle device, 16 is a second throttle device, 17 is an evaporator, 18 is a temperature detector, and 19 is a flow rate controller.

The rectification column 10 has a diameter of about several centimeters and a length of several to several tens of centimeters.
It has a tubular shape with a diameter of 1 cm, and is made up of a large number of fillings. The packing increases the contact area between the refrigerant liquid with a high composition of high-boiling components flowing down in the rectification column 10 and the refrigerant vapor with a high composition of low-boiling components rising in the rectification column 10, thereby increasing the effect of rectification. It is meant to be demonstrated. As for the specific structure of this filling, for example, the wire diameter is about 0.2 to 0.4 mm, and the diameter and length are each about 2 mm.
It is a spring-like thing with a diameter of ~3 mm.

The operation of the refrigeration system configured as described above will be explained below. First, the refrigerant vapor compressed by the compressor 8 is partially converted into a condensate by the condenser 9 and enters the rectification column 10, where the top vapor V has a high composition of low-boiling components and the bottom liquid L has a high composition of high-boiling components. It is separated into L is stored in the reheater 11 and heated to become saturated steam. By the action of the second flow control valve 14, part of it is lowered in pressure by the second throttle device 16 and then returned to the compressor, and the rest is sent to the rectification column 10. The rectification column 10 is circulated to the bottom of the column.
used as a heat source. On the other hand, V is the tower top condenser 12
It is condensed into a saturated liquid and stored in the condenser 12, and a part of it is sent to the first throttle device 15.
The rest is circulated to the top of the rectification column 10 by the action of the first flow control valve 13 in order to enhance the separation effect of the rectification column 10. Here, if there is no circulating amount of V to the top of the rectification column 10, the composition of V will be almost the same as the composition of the uncondensed vapor at the outlet of the condenser 9, and the refrigerant will be evaporated in the evaporator 17 with that composition. The compressor generates low temperature and returns to the compressor 8. When the amount of V circulating to the top of the rectification column 10 increases, this circulating liquid flows down inside the rectification column 10 and passes through the rectification column 1.
Since it comes into contact with the rising vapor on the surface of the filling in the V and is rectified, the composition of the low boiling point components in the V increases, and the refrigerant with a high composition of low boiling point components flows to the evaporator 17, making it possible to obtain a lower temperature. can.

In this way, by adjusting the opening degree of the first flow control valve 13, the capacity of the refrigeration system can be controlled.
Furthermore, if there is no circulating vapor amount of L to the bottom of the rectification column 10, the composition of L is almost the same as the composition of the condensate at the outlet of the condenser 9. When the amount of circulating steam increases, the circulating steam rises in the rectifying column 10 and comes into contact with the flowing liquid on the surface of the packing in the rectifying column 10, causing rectification, which increases the composition of high boiling point components in L. Become. Therefore, a liquid with a high composition of high-boiling components accumulates in the lower part of the rectification column 10, and the composition of high-boiling components in the refrigerant flowing through the compressor 8, condenser 9, and evaporator 17 decreases, lowering the temperature. Obtainable.

In this way, by adjusting the opening degree of the second flow control valve 14, the capacity of the refrigeration system can be further controlled. The flow rate is adjusted by the first flow rate control valve 13 and the second flow rate control valve 14 in the evaporator 1.
The temperature of the object to be cooled at No. 7 is detected by a temperature detector 18 and controlled by a flow rate controller 19.

The above configuration requires an external heat source to heat the reheater 11 and an external cooling source to cool the tower top condenser 12, but by using one rectification column, the mixed refrigerant components can be The separation effect can be enhanced, a lower temperature can be obtained in the evaporator 17, and the capacity of the refrigeration system can be easily controlled by adjusting the amount of refrigerant circulated to the rectification column.

Further, in this embodiment, the first flow rate control valve 13 and the first throttle device 15 or the second flow rate control valve 14 and the second throttle device are shown separately, but they may be used in combination.

Effects of the Invention As described above, according to the present invention, a rectification column is provided at the outlet of the condenser, and the vapor separated at the upper part of the rectification column is liquefied and then separated into two circuits, one of which is sent to the rectification column.
The other is connected to the evaporator through a first flow rate control valve to increase the separation effect of refrigerant components and obtain a lower temperature, and by controlling the first flow rate control valve via a flow rate controller. This has the excellent effect of making it easier to control the capacity of the refrigeration system.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional refrigeration system using a non-azeotropic mixed refrigerant, and FIG. 2 is a circuit diagram of an embodiment of the refrigeration system of the present invention. 8... Compressor, 9... Condenser, 10... Rectification column, 11... Reheater, 12... Tower condenser, 13
...first flow rate control valve, 14...second flow rate control valve,
15...first diaphragm device, 16...second diaphragm device,
17... Evaporator, 18... Temperature detector, 19...
Flow controller.

Claims (1)

[Claims] 1 Using a non-azeotropic mixed refrigerant, a compressor, a condenser, a rectification column, an overhead condenser provided at the top of the rectification column, a first flow rate control valve, a first throttling device, and an evaporator are connected in a ring. After being liquefied in the top condenser, it is separated into two circuits, one of which is returned to the top of the rectification column, and the other is connected to the evaporator via a first flow control valve and a first throttle device. After being evaporated in a reheater installed at the bottom of the rectification column, it is separated into two circuits, one of which is returned to the bottom of the rectification column, and the other is a second flow rate control valve and a second throttle device. A refrigeration system including a capacity controller that is connected to the compressor via the compressor and controls the first flow rate control valve and the second flow rate control valve to perform capacity control.