JPH03168279A - Working fluid - Google Patents

Abstract

PURPOSE:To obtain a working fluid, containing specific amounts of difluoromethane, chlorodifluoromethane 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 <=85wt.%, preferably <=70wt.% difluoromethane (R32), <=90wt.%, preferably <=85wt.% chlorodifluoromethane (R22) and 10-85wt.%, preferably 15-80wt.% dichlorotrifluoroethane (R123).

Description

[Detailed Description of the Invention] Industrial Application Fields of the Present Invention (1) Conventional technology related to working fluids used in refrigerators, heat pumps, etc. (1) Fluorocarbons (hereinafter referred to as A halogenated hydrocarbon called ROO or ROO○ is known, and its usage temperature is approximately 0 to approximately 5.
Although dichlorodifluoromethane (CCl*F*, R12) is commonly used in the temperature range of 0°C, it is widely used as a working fluid in refrigerator kites, car air conditioners, large refrigerators, etc., but the problem to be solved by the invention is However, in recent years, depletion of the stratospheric ozone layer by fluorocarbons has become a global environmental issue, and an international convention has already been established regarding fluorocarbons (hereinafter referred to as specified fluorocarbons), which have a large ability to deplete the stratospheric ozone. The amount of use and production has been regulated, and there is also a movement to abolish the use and production of specified fluorocarbons in the future.Now, R12 is the ozone depletion coefficient (trichlorofluoromethane (CClsF)).
When the stratospheric ozone depletion capacity of the stratospheric ozone depletion capacity is 1, the stratospheric ozone depletion capacity 9 (hereinafter referred to as ○DP) is 1. 0 specified CFCs, and in the present day when refrigeration and air conditioning equipment is widely used, reducing the use and production of &R12 will have a tremendous impact on the human living environment (\ Therefore, the ability to deplete stratospheric ozone is small. There is a strong demand for the early development of a working fluid that can replace R12.

The present invention has been attempted in view of the above-mentioned problems, and provides a working fluid that has a small effect on the stratospheric ozone layer and is an alternative to R12. Those who can solve the above problems should at least
aH CI 2F 3) Difluoromethane 0 to approximately 85% by weight Chlorodifluoromethane O to approximately 90% by weight Dichlorotrifluoroethane approximately 10 to approximately 85% by weight It is characterized by difluoromethane O ~ approximately 70% by weight.
Chlorodifluoromethane O ~ about 85% by weight dichlorotrifluoromethane A desirable composition range is about 15% to about 80% by weight. difluoromethane (ODP=O), which is a fluorocarbon that does not contain any Ethane (ODP=0.02)
By forming a mixture of at least three types of R12, it is possible to make the effect on the stratospheric ozone layer much smaller than that of R12. It is possible to provide a working fluid that can be used in current equipment as an alternative to L and R12, which has a vapor pressure similar to that of R12 at temperatures of approximately 0 to approximately 50°C, which is the operating temperature of machines, heat pumps, etc. In particular, the ODP in the above combinations and combination ranges is 0.
01 to 0.05.It 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. Although it is possible to expect a higher coefficient of performance than Rl2 by keeping the differences close to each other, some examples of working fluids according to the present invention will be explained below using diagrams. Explanation: Figure 1 (.t. Difluoromethane (R32), chlorodifluoromethane (R22), 2,2-dichloro 1,
I, l-trifluoroethane (R l 2 3)
The working fluid Q is composed of a mixture of three types of fluorocarbons. The equilibrium state at constant temperature and constant pressure is shown using triangular coordinates.
At each vertex of the triangle, single substances are arranged counterclockwise from the upper vertex in descending order of boiling point. It is also expressed as the ratio of the distance to each side of
The distance between the point and the side of the triangle is 1, which corresponds to the ratio of the material set at the vertex of the triangular coordinates on the side opposite the side.
In the figure I (& temperature 0℃・pressure 2.116kg
This is the vapor-liquid equilibrium line of the mixture at /cm2G, and this temperature and pressure correspond to the saturated state of R12.
R120℃ equivalent) The upper line of 1 is the saturated vapor phase line.The upper line of 1 is the vapor-liquid equilibrium line. Tonan Mata 2 {Friend Temperature 50℃・Pressure 11.37
is the vapor-liquid equilibrium line of the mixture at 3 kg/cm"G,
This temperature and pressure also correspond to the saturated state of R12.As can be seen from the figure, R32, R22, and R123 are each 0 to approximately 80% by weight, 0 to approximately 90% by weight, approximately 10 to approximately 85% by weight.
A certain range by weight is desirable because it has almost the same vapor pressure as R12 at the usage temperature of about 0 to about 50°C. 85 weight approximately 15 to approximately 80
It is particularly desirable to have a vapor pressure approximately equal to that of R12 at all operating temperatures between 0°C and 50°C (i.e., from point At to point F1 in Figure 1). Table 1 shows the working fluid composition and ODP.

Points A1 to Cl in Table 1 and Figure 1 are the vapor-liquid equilibrium line (R12 5
Also, points D1 to Fl are on the saturated liquid line of the vapor-liquid equilibrium line (R12, equivalent to 50°C) 2, and the saturated gas phase line of the vapor-liquid equilibrium line (Rl2, equivalent to 0°C) 2. The plate temperature should be within the range between the phase line and the vapor-liquid equilibrium line (R12 equivalent to 0℃) and the saturated liquidus line.
・Pressure 2. 11 6 kg/cm”G (R 1
Therefore, under the conditions of the saturated vapor pressure of R12 at 0°C and 50°C, the working fluid C having the composition shown in Table 1 is in a saturated state or Achieves a gas-liquid equilibrium state at approximately 0 to approximately 50℃
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. (equivalent to ℃) 2 Intersection of forces explained only about the points on the inside of point A1 to point Fl In other words, water Temperature 0℃・Pressure 2.118kg/
cm”G and temperature 50℃・pressure 1 1.373kg/c
By performing the same operation on a working fluid having a composition that reaches a vapor-liquid equilibrium state at m'G (both of which correspond to the saturated state of R12), condensation approximately equal to Rl2 can be obtained at a usage temperature of approximately 0 to approximately 50°C. It is possible to obtain the temperature and evaporation temperature using a working fluid a composed of a mixture of three types of fluorocarbons: R32, R22, and l,2-dichlorotrifluoroethane (Rl23a), as shown in Figure 2. The equilibrium state at constant temperature and constant pressure is shown using triangular coordinates. In Figure 2, 3 (top temperature 0°C, pressure 2.
It is the vapor-liquid equilibrium line of the mixture at 1 1 6 kg/cm"G, and is also 4 (friend temperature 501 - pressure 11.37
The vapor-liquid equilibrium line of the mixture at 3 kg/cm"G is
In this case l;l. ．． R32, R22 and R123a each contain 0 to approximately 85% by weight. O ~ Approximately 90 weight study abbreviation lO
〜Approximately 85% by weight <. R32, R22 is desirable because it has almost the same vapor pressure as R12.
and R123a each in an amount of O to approximately 70% by weight. O ~ about 8
Table 2 shows the working fluid composition and ODP at points A2 to F2 in FIG. 2, which is particularly desirable.

Points A2 to C2 in the figure are the vapor-liquid equilibrium line (R12 5
Also, points D2 to F2 are on the saturated liquid line of vapor-liquid equilibrium line (Rl2, equivalent to 50°C) 4, and the saturated gas phase line of vapor-liquid equilibrium line (Rl2, equivalent to 0°C) 3. The transition temperature θ℃ must be within the range between the phase line and the vapor-liquid equilibrium line (R12 equivalent to 0℃) 3, the saturated liquidus line.
・Pressure 2. 11 6 kg/cm”G (R 1
(corresponding to the saturated state of 2), what is the state of vapor-liquid equilibrium?
Therefore, the working fluid Gi having the composition shown in Table 2
Realizes a saturated state or a vapor-liquid equilibrium state under the condition of saturated vapor pressure of Rl2 at 0°C and 50°C, approximately 0 to approximately 50
At the usage temperature shown in Table 2, it is possible to obtain condensation and evaporation temperatures almost equal to R12 by operating at the saturated vapor pressure of R12 at the same temperature. Force intersection explained only about the points on the line (R12 equivalent to 50℃)
kg/cm”G and temperature 50℃・pressure 1 1.37
3kg/cm”G (both correspond to the saturated state of Rl2)
By performing the same operation on a working fluid that has a composition that is in vapor-liquid equilibrium at , it is possible to obtain condensation and evaporation temperatures that are approximately equal to R12 at a usage temperature of approximately 0 to approximately 50°C. In the above embodiments, the force exerted on the working fluid is created by a mixture of three types of fluorocarbons.Of course, it is also possible to create a force in the working fluid using a mixture of four or more types of fluorocarbons, including structural isomers. Yes, here ▲ Difluoromethane O
~ Approximately 85% by weight Chlorodifluoromethane O ~ Approximately 90% by weight Dichlorotrifluoroethane Contains approximately 10% to approximately 85% by weight Steam that is approximately equivalent to R12 at a usage temperature of approximately 0 to approximately 50°C It is desirable because it has a high pressure (1 and also difluoromethane O ~ about 70 wt.
Chlorodifluoromethane 0 to approximately 85% by weight κ dichlorotrifluoroethane approximately 15 to approximately 80% by weight. It is particularly desirable to have ○DP in the above combinations and combinations range is 0
．． 01 to 0.05, it 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 be blown with a temperature gradient in the condensation and evaporation processes. By constructing a Lorenz cycle with close temperature differences, R12
Effects of the Invention As is clear from the above explanation, although a higher coefficient of performance can be expected than that of the present invention, it is possible to By specifying the range of mixtures of three or more types of fluorocarbons that also contain hydrogen, we have: (1) Selected working fluids to have a much smaller impact on the stratospheric ozone layer than R12. (2) It has the same vapor pressure as R12 at the operating temperature of the equipment, and can be used in current equipment as a substitute for L and Rl2, and (3) Non-azeotropic mixtures. Using the property of temperature gradient, R1
Even if it has an effect such that a performance coefficient higher than 2 can be expected.

[Brief explanation of the drawing]

Figures 1 to 2 {Top: Working fluid α composed of a mixture of three types of fluorocarbons. Liquid equilibrium line (R120℃ equivalent), 2,4・
...Vapour-liquid equilibrium line (Rl2 equivalent to 50°C).

Claims (2)

[Claims] (1) A working fluid containing at least three types of fluorocarbons: 85% by weight or less of difluoromethane, 90% by weight or less of chlorodifluoromethane, and 10 to 85% by weight of dichlorotrifluoroethane. (2) A working fluid containing at least three types of fluorocarbons: 70% by weight or less of difluoromethane, 85% by weight or less of chlorodifluoromethane, and 15 to 80% by weight of dichlorotrifluoroethane.