JPH03168274A - Working fluid - Google Patents

Abstract

PURPOSE:To obtain a working fluid, containing specific amounts of chlorodifluoromethane, tetrafluoroethane and dichlorotrifluoroethane, hardly affecting the stratospheric ozonosphere and used for refrigerators, heat pumps, etc. CONSTITUTION:The objective working fluid containing at least three kinds of fluorocarbons of <=90wt.%, preferably 5-85wt.% chlorodifluoromethane (R22), <=95wt.%, preferably <=85wt.% tetrafluoroethane (R134a) and <=55wt.%, preferably <=50wt.% dichlorotrifluoroethane (R123).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a working fluid used in refrigerators, heat pumps, etc.

Conventional Technology Conventional Halogenated hydrocarbons called fluorocarbons (hereinafter referred to as R○○ or R○○○) are known as working fluids in refrigerators, heat pumps, etc., and the usage temperature is the condensation temperature and/or Or the evaporation temperature is about 0 to about 5
Usually used in the 0°C range. Among them, dichlorodifluoromethane (CCl2F2, R12) is widely used as a working fluid in refrigerated car air conditioners, dog-shaped refrigerators, and the like.

Problems to be Solved by the Invention In recent years, the depletion of the stratospheric ozone layer by fluorocarbons has become a global environmental problem, and some fluorocarbons (hereinafter referred to as specific fluorocarbons), which have the ability to deplete the stratospheric ozone, ) has already been regulated by international treaties, and there is also a movement to abolish the use and production of specified fluorocarbons in the future. ) When the stratospheric ozone depletion ability of
) is 1. Currently, refrigeration and air conditioning equipment is widely used, and reducing the amount of R12 used and produced will have a tremendous impact on human living environments. Therefore, even though there is a strong demand for the early development of a working fluid that can replace R12 due to its low ability to deplete the bottom ozone, the present invention (
This was attempted in view of the above-mentioned problems, and provides a working fluid that has a small effect on the stratospheric ozone layer and can be used as an alternative to t and kR12.

Means for Solving the Problems The present invention solves the above problems by using at least three types of chlorofluorocarbons: chlorodifluoromethane (CHCIFa), tetrafluoroethane (C2H2F4), and dichlorotrifluoroethane (C2HC1aFt). Chlorodifluoromethane O~approximately 90% by weight Tetrafluoroethane 0~approximately 95% by weight Dichlorotrifluoroethane 0~approximately 55% by weight. Australia Black difluoromethane approx. 5 to approx. 85 weight κ Tetrafluoroethane O to approx. 85
Weight κ dichlorotrifluoroethane O~approximately 50% by weight
Even if the range of composition is desirable, the present invention is still effective.The above combination allows the working fluid to be made of tetrafluoroethane (○DP=O), which is a fluorocarbon that does not contain chlorine in its molecular structure and has almost no ozone depletion ability. and,
Chlorodifluoromethane (○D
P=0. 05) and dichlorotrifluoroethane (ODP=0.02), it is possible to make the effect on the stratospheric ozone layer much smaller than that of R12. Moreover, by setting the above-mentioned composition within a certain range, the present invention achieves R1 at approximately 0 to 50 degrees Celsius, which is the operating temperature of refrigerators, heat pumps, etc.
This makes it possible to provide a working fluid that can be used in current equipment as a substitute for L and R12, and has a vapor pressure comparable to that of L and R12. O in particular in the above-mentioned combinations and ranges
DP is 0.01~0. This is expected to be a very promising working fluid as an alternative to R12.In addition, such a mixture will be a non-azeotropic mixture, and will have a temperature gradient in the condensation and evaporation processes. By paying close attention to the Lorenz cycle, a higher coefficient of performance than R12 can be expected.Examples Hereinafter, some examples of working fluids according to the present invention will be described with reference to the drawings.

Figure l shows chlorodifluoromethane (R22), 1,
1, 1. 2-tetrafluoroethane (R13
4a), 2,2-dichloro o-1. 1. Working fluid α from a mixture of three types of fluorocarbons, 1-trifluoroethane (R123) The equilibrium state at constant temperature and constant pressure is shown using triangular coordinates. In this triangular coordinate system, single substances are placed at each vertex of the triangle in order of decreasing boiling point, starting from the upper vertex and moving counterclockwise.
The composition ratio (weight ratio) of each year at a certain point on the coordinate plane
ζ is expressed as the ratio of the distance between the point and each side of the triangle.In this case, the distance between the point and the side of the triangle (y) is the ratio of the distance between the point and each side of the triangle. Corresponds to the ratio.In Figure 1, 1 + 1 Temperature 0°C, Pressure 2.
This is the vapor-liquid equilibrium line of the mixture at 116 kg/cm"G, and this temperature and pressure correspond to the saturated state of R12. The line below the equilibrium line (R12, equivalent to 0°C) 1 represents the saturated liquidus line.The range between these two lines is in a state of vapor-liquid equilibrium.It is also 2C.Temperature: 50°C, Pressure: 11. This is the vapor-liquid equilibrium line of the mixture at 373 kg/cm'G, and this temperature and pressure also correspond to the saturated state of R12.

As can be seen from the figure, R22, R134a and R123
are respectively 0 to approximately 90% by weight and 0 to approximately 95% by weight (0 to approximately 50°C).
It is desirable that R22, Rl 34 a and R123 each have a vapor pressure of about 5 to about 85% by weight.0 to about 8.
5 weight% Assembling range C such that approximately 5 to approximately 50% by weight
R12 at all operating temperatures between 0°C and 50°C
Table 1 shows the working fluid composition and DP at points A1 to F1 in FIG. Point A1 to point Cl are the vapor-liquid equilibrium line (
Point Fl is on the saturated vapor line of the vapor-liquid equilibrium line (R12 equivalent to 50°C) 2, and the saturated vapor line of the vapor-liquid equilibrium line (R12 equivalent to 0°C) 1. It must be within the range between the saturated liquidus line of vapor-liquid equilibrium line (equivalent to R120℃) 1.
Pressure 2. At 1 1 6 kg/cm2G (corresponding to the saturated state of Rl 2), a gas-liquid equilibrium state is reached. In addition, points D1 and E1 are on the saturated liquid line of the vapor-liquid equilibrium line (R12, equivalent to 0°C) 1, and the vapor-liquid equilibrium line (Rl2
50℃ equivalent) 2 saturated gas phase line and vapor liquid equilibrium line (Rl2
．． Temperature: 50°C, Pressure: 1. 3 7
3 kg/cm2G (equivalent to the saturated state of R 1 2)
At this point, there is a gas-liquid equilibrium state. Therefore, a working fluid I-L having the composition shown in Table 1 can achieve a saturated state or a vapor-liquid equilibrium state under the conditions of the saturated vapor pressure of R12 at Table 1 and 50°C. At a usage temperature of 50° C., by operating at the saturated vapor pressure of R12 at the same temperature, it is possible to obtain condensation and evaporation temperatures almost equal to R12.

Here, ζ is a force support that explains only the points on the vapor-liquid equilibrium line (R12, equivalent to 0°C) 1 or the vapor-liquid equilibrium line (R12, equivalent to 50°C) 2. A point inside points A1 to Fl, that is, M Temperature 0℃・Pressure 2.116kg/cm2G
and temperature 50℃・pressure 11.373 kg/cm
By performing the same operation for a working fluid that has a composition that reaches a vapor-liquid equilibrium state at "G" (both correspond to the saturated state of R12), condensation approximately equal to that of R12 can be achieved at a usage temperature of approximately 0 to approximately 50°C. This makes it possible to obtain temperature and evaporation temperature.

Figure 2 i: LR22, R134a, 1. The working fluid Q is kept at a constant temperature by a mixture of three types of fluorocarbons, 2-dichlorotrifluoroethane (R123a).
The equilibrium state at constant pressure is shown using triangular coordinates. In Figure 2, 3ζ, temperature 0°C, pressure 2.
It is the vapor-liquid equilibrium line of the mixture at 116 kg/cm2G, and it is also 4 (yo Temperature 501 - Pressure 11.373
In this case, the vapor-liquid equilibrium line of the mixture at kg/cm''G is such that !iR22, Rl 34a and R123a are each 0 to approximately 90% by weight. A certain range car-x R22, R13 is desirable because it has almost the same vapor pressure as R12.
4a and R123a each weigh approximately 5 to approximately 85% by weight 0
- approximately 85 weight yarn, braiding range force such that it is approximately 5 to approximately 50% by weight (particularly desirable).

Table 2 shows the working fluid combinations and DP at points A2 to F2 in FIG. Points A2 to C2 are the vapor-liquid equilibrium line (
Point F2 is on the saturated liquid line of vapor-liquid equilibrium line (R12 equivalent to 50°C) 4, and the saturated vapor phase line of vapor-liquid equilibrium line (R12 equivalent to 50°C) 3 The liquid equilibrium line (RI equivalent to 20°C) 3 must be within the range between the saturated liquidus line and both lines in Table 2. Temperature 0°C/Pressure 2.
1 ' At 1.6 kg/cm2G (corresponding to the saturated state of R12), it is not a vapor-liquid equilibrium state. Also, point D2 and point E2 are on the saturated liquid line of the vapor-liquid equilibrium line (corresponding to R12 0°C) 3, and the gas-liquid It must be within the range between the saturated gas phase line of equilibrium line (R12, equivalent to 50°C) 4 and the saturated liquidus line of vapor liquid equilibrium line (R12, equivalent to 50°C) 4. Temperature 50°C, pressure 11 ．． 373kg/cm”G
(corresponding to the saturated state of R12), a gas-liquid equilibrium state is reached. Therefore, a working fluid having the composition shown in Table 2 can achieve a saturated state or a vapor-liquid equilibrium state under the condition of R12's saturated vapor pressure at 10°C and 50°C.
At a usage temperature of 0°C, by operating at the saturated vapor pressure of R12 at the same temperature, it is possible to obtain condensation and evaporation temperatures almost equal to R12. Force t explained only for points on the vapor-liquid equilibrium line (R12 equivalent to 50°C) 4 (R12 equivalent to 0°C) 9 inside points A2 to F2, i.e. plate Temperature 0°C, pressure 2.116 kg/cm ”G
and temperature 50℃・pressure 11.37 3 kg/cm"G
(Both correspond to the saturated state of R12) By performing the same operation for a working fluid having a composition that is in a vapor-liquid equilibrium state, the condensation temperature and evaporation temperature are approximately equal to R12 at the operating temperature of approximately 0 to approximately 50°C. It is possible to obtain the temperature.

Figure 3 (R22, 1, 1, 2. 2-
The equilibrium state of a working fluid α composed of a mixture of three types of fluorocarbons, tetrafluoroethane (R134) and R123, at a constant temperature and constant pressure is shown using triangular coordinates. Temperature 0℃・Pressure 2
．． It is the vapor-liquid equilibrium line of the mixture at 116 kg/cm2G, and it is also 6 (Yo) Temperature 501, Pressure 1 1.
3 7 3 Gas-liquid equilibrium line of mixture at kg/cm2G In this case, 4LR22, R134 and R12
3 is approximately 25 to approximately 90 weight KO to approximately 75 weight group, respectively.
A certain range of assembly force such that 0 to approximately 55% by weight <. R22, Rl34 and R12 are desirable because they have a steam third surface pressure almost equivalent to R12.
Particularly desirable is the assembly range force such that 3 is about 30 to about 85 weight κ O to about 70 weight % and 0 to about 50 weight % (1) The group precepts and ODP are shown in Table 3. Points A3 to C3 are on the vapor-liquid equilibrium line (
Point F3 is on the saturated liquid line of vapor-liquid equilibrium line (R12 equivalent to 50°C) 6, and the saturated vapor phase line of vapor-liquid equilibrium line (R12 equivalent to 50°C) 5 The liquid equilibrium line (R12 equivalent to 0℃) is within the range between the saturated liquidus lines of 5.
Pressure 2. At 1 1 6 kg/cm2G (corresponding to the saturated state of Rl 2), a gas-liquid equilibrium state is reached. In addition, point D3 and point E3 are on the saturated liquid line of the vapor-liquid equilibrium line (R12, equivalent to 0°C) 5, and the vapor-liquid equilibrium line (Rl2
50℃ equivalent) 6 saturated gas phase line and vapor liquid equilibrium line (R12
Temperature: 50°C, Pressure: 1. 3 7
3 kg/cm”G (equivalent to the saturated state of R 1 2)
At this point, there is a gas-liquid equilibrium state. Therefore, working fluids having the composition shown in Table 3 (above) must be used at approximately 0°C to approximately 50°C to achieve a saturated state or vapor-liquid equilibrium state under the conditions of R12's saturated vapor pressure at 0°C and 50°C. At temperature,
By operating at the saturated vapor pressure of R12 at the same temperature, it is possible to obtain condensation and evaporation temperatures almost equal to -R12. The force explained only for the points on the liquid equilibrium line (RL2, equivalent to 50℃) 6 (the force inside points A3 to F3)
Name plate Temperature 0℃・Pressure 2.116kg/cm2G and Temperature 50℃・Pressure 11, 373 kg/cm2G
(Both correspond to the saturated state of R12) By performing the same operation for a working fluid that has a gas-liquid equilibrium state, the condensation temperature and evaporation temperature are approximately equal to Rl2 at a usage temperature of approximately 0 to approximately 50°C. Figure 4 ii A working fluid Q composed of a mixture of three types of fluorocarbons, R22, R134, and R123a. Even the one shown is 71 in Figure 4. Temperature 0℃, pressure 2
．． It is the vapor-liquid equilibrium line of the mixture at 1 1 6 kg/cm"G, and 8 (temperature 50°C, pressure 1 1.
It is the vapor-liquid equilibrium line of the mixture at 3 7 3 kg/cm"G. In this case, R22, R134 and R12
3a is about 25 to about 90% by weight, respectively. Assembling range force such that 0 to approximately 75% by weight 0 to approximately 55% by weight <, R12
It is desirable because it has almost the same vapor pressure as R22, R
134 and Rl23a each about 30 to about 85% by weight
．． 0 to approximately 70% by weight. Particularly desirable is an assembly range force such that O~approximately 50% by weight 1 Points A4 to F4 in Figure 4
The working fluid composition and ○DP are shown in Table 4. Points A4 to C4 are vapor-liquid equilibrium lines (R12 equivalent to 50°C) 8
Point F4 is on the saturated vapor phase line of the vapor-liquid equilibrium line (R12 5
If it is on the saturated liquid line of 8 (equivalent to 0℃), go to 4. It must be within the range between the lines of the saturated liquidus line.Temperature 0°C/Pressure 2.
116 kg/cm2G (corresponding to the saturated state of R12, it becomes a gas-liquid equilibrium state. Also, point D4 and point E
4 is on the saturated liquid line of the vapor-liquid equilibrium line (R12 equivalent to 0°C) 7, and the saturated vapor phase line of the vapor-liquid equilibrium line (Rl2 equivalent to 50°C) 8 and the vapor-liquid equilibrium line (Rl2 equivalent to 50°C) 8
Temperature: 50°C, Pressure: 11. 373kg/cm”G (R1
(equivalent to the saturated state of 2), what is the vapor-liquid equilibrium state?
Therefore, the working fluid having the composition shown in Table 4
By realizing a saturated state or a vapor-liquid equilibrium state under the conditions of the saturated vapor pressure of R12 at 50°C and 50°C, and operating at the saturated vapor pressure of R12 at the same temperature at a usage temperature of about 0 to about 50°C, R12 The condensing temperature is almost equal to
This makes it possible to obtain the evaporation temperature.

Here, c yo Vapor-liquid equilibrium line (R1.2 equivalent to 0℃) 7
Alternatively, only points on the vapor-liquid equilibrium line (R12 equivalent to 50°C) 8 are explained. Points inside points A4 to F4, that is, water temperature 0°C and pressure 2. 116kg/
cm'G and temperature 50℃・pressure 11.373kg/cm
By performing the same operation on a working fluid having a composition that is in vapor-liquid equilibrium at QG (both of which correspond to the saturated state of R12), the condensation temperature is approximately equal to that of R12 at a usage temperature of approximately 0 to approximately 50°C. This makes it possible to obtain the evaporation temperature.

In the above embodiments, the working fluid is composed of a mixture of three types of fluorocarbons.Of course, the working fluid can also be composed of a mixture of four or more types of fluorocarbons, including structural isomers. , in this case, chlorodifluoromethane O to about 90% by weight, tetrafluoroethane O to about 95%
Weight Rice: Dichlorotrifluoroethane 0 to approximately 55% by weight
A composition range in which L
~ In addition, chlorodifluoromethane approximately 5 to approximately 85% by weight, tetrafluoroethane 0 to approximately 85% by weight, dichlorotrifluoroethane 0 to approximately 50% by weight {all between 0°C and 50°C It is particularly desirable because it has a vapor pressure almost equal to that of R12 at the operating temperature of R12. In particular, the ODP in the above combinations and ranges is 0.
．． 01~0. This mixture is expected to be a very promising working fluid as a replacement for tl and R12.In addition, such a mixture will be a non-azeotropic mixture, and will have a temperature gradient in the condensation and evaporation processes. By constructing Lorenz cycles in close proximity, R1
A performance coefficient higher than that of 2 can be expected.

Effects of the Invention As is clear from the above explanation, the present invention & above uses a working fluid consisting of three or more types: fluorocarbons that do not contain chlorine in their molecular structure, and fluorocarbons that contain both chlorine and hydrogen in their molecular structure. By specifying the range of mixtures and non-mixtures, it is possible to (1) expand the range of choices of working fluids in order to make the effect on the stratospheric ozone layer much smaller than that of R12; 2) It has a vapor pressure comparable to that of R12 at the operating temperature of the equipment, and can be used in current equipment as an alternative to R12.

(3) Taking advantage of the temperature gradient properties of non-azeotropic mixtures, R1
This has the effect that a performance coefficient higher than that of 2 can be expected.

[Brief explanation of the drawing]

Figures 1 to 4 show the equilibrium state of a working fluid α composed of a mixture of three types of fluorocarbons using triangular coordinates at constant temperature and constant pressure. 7... Gas-liquid equilibrium line (Rl2
(equivalent to 0℃), 2, 4, 6. 8...
Gas-liquid equilibrium line (R12 equivalent to 50°C).

Claims (2)

[Claims] (1) A working fluid containing at least three types of fluorocarbons: 90% by weight or less of chlorodifluoromethane, 95% by weight or less of tetrafluoroethane, and 55% by weight or less of dichlorotrifluoroethane. (2) A working fluid containing at least three types of fluorocarbons: 5 to 85% by weight of chlorodifluoromethane, 85% by weight or less of tetrafluoroethane, and 50% by weight or less of dichlorotrifluoroethane.