JPH03168261A - Working fluid - Google Patents

Abstract

PURPOSE:To obtain a working fluid containing specific amounts of chlorodifluoromethane, difluoroethane and chlorodifluoroethane, hardly affecting the stractospheric ozonosphere and used for refrigerators, heat pumps, etc. CONSTITUTION:The objective working fluid containing at least three kinds of fluorocarbons of 5-75wt.%, 45-65wt.% chlorodifluoromethane (R22), <=95wt.%, preferably <=40wt.% difluoroethane (R152a) and <=55wt.%, preferably 20-50wt.% chlorodifluoroethane (R142b).

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to working fluids used in refrigerators, heat bombs, etc. A halogenated hydrocarbon called ○ or ROOO is known, and its usage temperature ranges from approximately 0 to approximately 5.
Usually used in the 0°C range. Among them, dichlorodifluoromethane (CC12F2, R12) is widely used as a working fluid in refrigerated car air conditioners and large refrigerators.

Problems to be Solved by the Invention In recent years, depletion of the stratospheric ozone layer by fluorocarbons has become a global environmental problem, and fluorocarbons (hereinafter referred to as specified fluorocarbons) have a large ability to deplete the stratospheric ozone. Regarding the use and production of specific fluorocarbons, which have already been regulated by international treaties,
There is a movement to abolish production. Now, R12 is the ozone depletion coefficient (trichlorofluoromethane (CC1sF)
) is a specific fluorocarbon with a stratospheric ozone depletion capacity 9 (hereinafter referred to as ○DP) of 1.0, and the amount of R12 used and The impact that a reduction in production would have on the human living environment would be enormous (°C).Therefore, the ability to deplete the ozone in the lower strata is small, and there is a strong demand for the early development of a working fluid that can replace R12.

The present invention was attempted in view of the above-mentioned problems, and is intended to provide a working fluid that has a small effect on the stratospheric ozone layer (as an alternative to R12).

Means for Solving the Problems The present invention aims to solve the above problems.
Contains three types of fluorocarbons from 3C I F2) Chlorodifluoromethane approximately 5 to approximately 75 weight groups Difluoroethane O to approximately 95 weight groups Chlorodifluoroethane 0 to approximately 5 weight groups
It is characterized by a composition range of 5% by weight, and 'lI dichlorodifluoromethane from approximately 45 to approximately 65% by weight.
A range of about 20 to about 50% by weight of difluoroethane O to about 40% by weight of chlorodifluoroethane is desirable.

Effect of the present invention (above) By the above-mentioned combination, the working fluid is difluoroethane (○DP=O), which is a fluorocarbon that does not contain chlorine in its molecular structure, which has almost no ozone-depleting ability, and Chlorodifluoromethane (○DP) is a fluorocarbon containing both chlorine and hydrogen.
=0. 05) and chlorodifluoroethane (OD
P=0. By forming a mixture of three types from R12, it is possible to make the effect on the stratospheric ozone layer much smaller than that of R12. Furthermore, by using the above-mentioned assembly range, the present invention achieves R12 at temperatures ranging from 0 to about 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 an alternative to L and R12, and has a vapor pressure comparable to that of L and R12. ○D especially in the above-mentioned combinations and ranges
P is 0. 03~O. This mixture is expected to be a very promising working fluid as an alternative to Oa, 11, and R12.In addition, such a mixture will be a non-azeotropic mixture, and will have a temperature gradient during the condensation and evaporation processes. By arranging Lorenz cycles in close proximity,
Examples of working fluids according to the present invention, which can be expected to have a higher performance coefficient than Rl2, will be described below with reference to figures.
1-difluoroethane (R152a), 1-chloro-1,1-difluoroethane (R 142b)
The equilibrium state of a working fluid α controlled by a mixture of three types of fluorocarbons at constant temperature and constant pressure is shown using triangular coordinates. In this triangular coordinate! At each vertex of the triangle, single substances are placed counterclockwise from the upper vertex in descending order of boiling point, and the ratio (weight ratio) of each component at a certain point on the coordinate plane It is expressed as the ratio of the distance to each side of the triangle. In this case, the distance between a point and the side of the triangle corresponds to the composition ratio of the substance written at the vertex of the triangular coordinates on the side opposite the side. In Figure 1, l is temperature 0℃ and pressure 2.116kg/cm2G.
This temperature and pressure correspond to the saturated state of R12. Gas-liquid equilibrium line (R120℃
The upper line of 1 is the saturated vapor phase vapor-liquid equilibrium line (R12
The line below 1 (equivalent to 0°C) represents the saturated liquidus line.The range between these two lines is in vapor-liquid equilibrium. 2ζ again, temperature 50℃, pressure 11. 373kg/cm
This is the vapor-liquid equilibrium line of the mixture at 2G, and this temperature and pressure also correspond to the saturated state of R12.As can be seen from the figure, R22, R152a and R142b are each approximately 5 to 5
Approximately 75 weight OA. 0 to about 95% by weight and 0 to about 55% by weight! It is desirable because it has almost the same vapor pressure as R12 at the usage temperature of about 0 to about 50°C.1 Further: R22, R152a and R152b each have a weight of about 45 to about 65 9l1. O to approximately 40% by weight Approximately 20 to approximately 50% by weight CyoO℃
It is particularly desirable because it has almost the same vapor pressure as R12 at all operating temperatures between
0. It is predicted that t's Rl2 will be a very promising working fluid as a substitute for 06 and t's Rl2.

Table 1 shows the working fluid strength and DP at points Al to Fl in FIG. Points Al to C1 are the vapor-liquid equilibrium line (
R12 is on the saturated vapor phase line of 2 (R12 equivalent to 50°C) 2, and the image of the saturated vapor line of the vapor-liquid equilibrium line (R12 equivalent to 0°C) 1 and the saturated liquidus line of the vapor-liquid equilibrium line (R1 equivalent to 20°C) 1 It must be within the range between the lines.Temperature 0℃・Pressure 2
．． At 116 kg/cm2G (corresponding to the saturated state of R12), there is a vapor-liquid equilibrium state. Also, points D1 to F1 are on the saturated liquid line of the vapor-liquid equilibrium line (corresponding to R12 0°C) 1, and the vapor-liquid equilibrium line ( Temperature: 50°C, Pressure: 11. 373kg/cm”G (R12
Therefore, the working fluid having the composition shown in Table 1 is saturated under the condition of R12's saturated vapor pressure at 0°C and 50°C. Alternatively, by realizing a vapor-liquid equilibrium state and operating at the saturated vapor pressure of R12 at the operating temperature of approximately 0 to approximately 50°C, it is possible to obtain condensation and evaporation temperatures approximately equal to that of R12. However, here are the four points: Force intersection explained only about points on the vapor-liquid equilibrium line (Rl2, equivalent to 0°C) 1 or the vapor-liquid equilibrium line (Rl2, equivalent to 50°C) 2. Rope board Temperature 0°C/Pressure 2. 116kg/cm
”G and temperature 50℃・pressure 11.37 3 kg/cm
By performing the same operation on a working fluid that has a gas-liquid equilibrium state at ``G'' (both correspond to the saturated state of R12), the condensation temperature is almost equal to R12 at a usage temperature of approximately 0 to approximately 50℃.・Although it is possible to obtain the evaporation temperature, in this example, the working fluid is composed of a mixture of three types of fluorocarbons. Of course, it is also possible to control the working fluid.Also, such a mixture becomes a non-azeotropic mixture, and a Lorene cycle is constructed in which the temperature difference between the blowing fluid and the heat source fluid is kept close to each other. Although it is possible to expect a higher coefficient of performance than that of R12, it is clear from the above explanation that the present invention's GEL working fluid is composed of fluorocarbons that do not contain chlorine in their molecular structure, and A mixture of three or more types of fluorocarbons that contain both chlorine and hydrogen in their structure. By specifying the range of the combination, (1) the effect on the stratospheric ozone layer is much smaller than that of Rl2. (2) Even if it is possible to expand the range of selection of working fluids, (2) it has a vapor pressure similar to that of R12 at the operating temperature of the equipment, and can be used in current equipment as a substitute for L and R12 (3) ) Using 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]

Figure 1 shows a structure made of a mixture of three types of fluorocarbons...
Gas-liquid equilibrium line (R12 equivalent to 0°C), 2... Gas-liquid equilibrium line (R12 equivalent to 50°C).

Claims (2)

[Claims] (1) A working fluid containing at least three types of fluorocarbons: 5 to 75% by weight of chlorodifluoromethane, 95% by weight or less of difluoroethane, and 55% by weight or less of chlorodifluoroethane. (2) 45 to 65% by weight of chlorodifluoromethane,
A working fluid containing at least three types of fluorocarbons, 40% by weight or less of difluoroethane and 20 to 50% by weight of chlorodifluoroethane.