JPH08319479A - Refrigerant - Google Patents

Abstract

PURPOSE: To obtain refrigerants free from the possibility of causing ozonosphere depletion and excellent in refrigerating performance, especially coefficient of performance. CONSTITUTION: A refrigerant consisting of HCFC-125 and HFC-134a, of which HCFC-125 accounts for more than 40wt.% to less than 90wt.% and HFC-134a accounts for more than 10wt.% to less than 60wt.%, or of which HCFC-125 accounts for more than 90wt.% to less than 100wt.% and HFC-134a accounts for more than 0wt.% to less than 10wt.%. A refrigerant consisting of HCFC-125 and HFC-134, of which HCFC-125 accounts for more than 40wt.% to less than 90wt.% and HFC-134 accounts for more than 10wt.% to less than 60wt.%, or of which HCFC-125 accounts for more than 90wt.% to less than 100wt.% and HFC-134 accounts for more than 0wt.% to less than 10wt.%.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a working fluid of a refrigerator, a so-called refrigerant.

[0002]

2. Description of the Related Art As conventional refrigerants, chlorofluorohydrocarbons, fluorohydrocarbons, azeotropic compositions thereof, and compositions having compositions in the vicinity thereof are known. These are called chlorofluorocarbons or chlorofluorocarbon refrigerants, and currently dichlorodifluoromethane (hereinafter referred to as chlorofluorocarbon), chlorodifluoromethane (hereinafter referred to as chlorofluorocarbon), and the like are mainly used. However, in recent years, it has been pointed out that some of the CFCs, when released into the atmosphere, destroy the ozone layer in the stratosphere, and as a result, have a serious adverse effect on the earth's ecosystem including humankind. Such a point is
Although it is hard to say that it has been scientifically proven, the trend is that regarding CFCs that have a high possibility of ozone depletion,
It is in the direction of controlling the use and production by international agreement. CFC-12 is a type of CFC subject to control
There is. With the spread of refrigeration and air-conditioning facilities, the demand for the use and production control of CFCs, which has been increasing every year, has a great impact on the current social mechanisms including the living environment.
Therefore, the development of a refrigerant having excellent refrigeration performance, particularly a coefficient of performance, has become an urgent issue. As a CFC that does not damage the ozone layer, pentafluoroethane (CFC-1)
25) is conceivable, but this has the drawback that the coefficient of performance is low.

Here, the coefficient of performance is indicated by the ratio of refrigerating capacity / compression work. The coefficient of performance corresponds to the efficiency of the refrigerant because the refrigerating capacity is the amount of heat per unit time taken by the object to be cooled and the compression work is the amount of work of power for operating the refrigerator per unit time. It is a thing.

[0004]

[Means for Solving the Problems] The inventors of the present invention have conducted various studies in order to obtain a new refrigerant having a good coefficient of performance and a small effect on the ozone layer even when it is discharged into the atmosphere. . As a result, Freon 125 and Freon-134a
And when blending Freon-134 in a specific ratio,
It was found that the coefficient of performance is superior to that of Freon 125.

That is, the present invention provides a refrigerant comprising pentafluoroethane (CFC-125) and 1,1,1,2-tetrafluoroethane (CFC-134a),
Refrigerants having one of the following mixing ratios: 40% by weight <CFC-125 <90% by weight and 10% by weight <CFC-134a <60% by weight; 90% by weight <CFC-125 <100% by weight and 0% by weight <Freon-134a <10% by weight.

Further, the present invention is a refrigerant comprising pentafluoroethane (CFC-125) and 1,1,2,2-tetrafluoroethane (CFC-134), which has one of the following compounding ratios. Refrigerant: 40 wt% <Freon-125 <90 wt% and 10 wt% <Freon-134 <60 wt%; 90 wt% <Freon-125 <100 wt% and 0 wt% <Freon-134 <10 wt% Pertain.

CFC-134a and CFC-134 exhibit the same effect in the composition of the present invention, and thus can be converted or mixed with each other.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The refrigerant of the present invention has a specific heat ratio smaller than that of CFC-22 and a discharge gas temperature of a compressor of CFC-22.
Since it is lower than 22, it is also suitable as a medium for a refrigerating cycle having a relatively high temperature, such as a heat pump type air conditioner.

The composition of the present invention can utilize the characteristics as a non-azeotropic composition. In general, for single compounds and azeotropic compositions, the evaporation temperature in the evaporator is constant because evaporation takes place under constant pressure, but for non-azeotropic compositions, the temperature is low at the evaporator inlet and It becomes hot at the exit. On the other hand, the fluid to be cooled is flowed so as to exchange heat with the flow of the refrigerant in the evaporator in a countercurrent direction, so that even if the evaporation temperature of the refrigerant is constant, there is a temperature gradient along the flow. That is, in the evaporator, the temperature difference between the refrigerant and the fluid to be cooled becomes smaller as the fluid to be cooled advances. When using the composition according to the present invention, it becomes possible to approach the temperature gradient of the cooled fluid in the evaporator, the efficiency of refrigeration,
That is, the coefficient of performance can be increased.

[0010]

EXAMPLES Examples and comparative examples will be shown below to further clarify the features of the present invention.

Examples 1 to 3 and Comparative Example 1 Freon-125 and Freon-134a were mixed at various ratios (weight ratios) shown in Table 1 to prepare refrigerants.

In a 1-hp refrigerating machine, the condensation start temperature of the refrigerant in the condenser is 50 ° C., the temperature of the refrigerant at the inlet of the evaporator is 0 ° C., the superheat of the evaporator is 5 ° C., and the refrigerant having the composition shown in Table 1 is used. Used and operated. Table 1 shows the maximum evaporation temperature (℃), refrigeration capacity (kcal / m ³ ), coefficient of performance and compressor discharge temperature (℃).

Table 1 also shows the results when only Freon-125 was used (Comparative Example 1).

FIG. 1 is a graph showing the relationship between Freon-125 and Freon-134a.

[0015]

[Table 1] Refrigerant composition (% by weight) Maximum evaporation Refrigeration capacity Performance coefficient Compressor discharge refrigerant Freon-125 Freon-134a Temperature (° C) (kcal / m ³ ) Temperature (° C) Comparative example 1 100 0 0.0 713 3.30 61.0 Example 1 95 5 0.6 713 3.46 61.1 Example 2 80 20 2.1 697 3.86 60.9 Example 3 60 40 3.0 3.0 650 4.20 60. 8

[Brief description of drawings]

FIG. 1 is a graph showing the performance of the refrigerant of the present invention.

Claims (2)

[Claims] 1. Pentafluoroethane (CFC-125)
And 1,1,1,2-tetrafluoroethane (CFC-1
Refrigerant consisting of 34a) having any one of the following blending ratios: 40% by weight <CFC-125 <90% by weight and 10% by weight CFC-134a <60% by weight; 90% by weight CFC <CFC- 125 <100 wt% and 0 wt% <Freon-134a <10 wt%. 2. Pentafluoroethane (CFC-125)
And 1,1,2,2-tetrafluoroethane (CFC-1
34) A refrigerant comprising any of the following blending ratios: 40% by weight <CFC-125 <90% by weight and 10% by weight CFC-134 <60% by weight; 90% by weight CFC- 125 <100% by weight and 0% by weight <CFC-134 <10% by weight.