JPH03168285A - Working fluid - Google Patents

Abstract

PURPOSE:To provide a working fluid reduced in the affection thereof on the ozone layer of the stratosphere and capable of being employed as a substitute of dichlorodifluoromethane (R12) by containing chlorodifluoromethane, chlorodifluoroethane and dichlorofluoroethane in a specific ratio. CONSTITUTION:The objective working fluid contains at least three kinds of freons comprising (A) 45-95wt.% (preferably 50-90wt.%) of chlorodifluoromethane (R22), (B) <=55wt.% (preferably <=50wt.%) of 1-chloro-1,1-difluoroethane (R142b) and <=45wt.% of 1,1-dichloro-1-fluoroethane (R141b). The working fluid is employed in freezers, heat pumps, etc.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to working fluids used in refrigerators, heat pumps, etc. A halogenated hydrocarbon called ROOO is known, and its usage temperature ranges from about 0 to about 5.
Among them, dichlorodifluoromethane (CCl2Fa, Rl2) is commonly used in the range of 0°C, but has a refrigeration limit.Although it is widely used as a working fluid for car air conditioners and large refrigerators, the problem that the invention is trying to solve is that fluorocarbons have changed in recent years. The depletion of the stratospheric ozone layer due to fluorocarbons has become a global environmental issue, and international treaties have already established the use and production of fluorocarbons (hereinafter referred to as specified fluorocarbons), which have a large ability to deplete the stratospheric ozone. In addition, there is a movement to abolish the use and production of specified CFCs in the future.Now, R12 is the ozone depletion factor (trichlorofluoromethane (CCIIF)).
It is a specific fluorocarbon with a stratospheric ozone depletion potential (hereinafter referred to as ODP) of 1.0, when the stratospheric ozone depletion potential of 1. The impact of the reduction in R12 production on the human living environment is enormous (1) Therefore, even though the ability to deplete stratospheric ozone is small and there is a strong demand for the early development of a working fluid that can replace R12, the present invention The present invention has been tried in view of the above-mentioned problems.The present invention provides a working fluid that has a small effect on the ozone layer in the Kobo stratosphere and can be used as an alternative to LR12.The present invention solves the problems described above. In order to solve the problem, at least three types of fluorocarbons are included: chlorodifluoromethane (CHCIFg), chlorodifluoroethane (C2HSC I Fm), and dichlorofluoroethane (CaHsC1aF). 0 to about 55% by weight of dichlorodifluoroethane 0 to about 45% by weight, particularly 50 to about 90% by weight of chlorodifluoroethane
The composition range of 0 weight group dichlorofluoroethane O to approximately 45 weight percent is desirable.The above combination allows the working fluid to contain chlorine and hydrogen in its molecular structure, which has an extremely low ozone depletion ability. Chlorodifluoromethane (ODP=
0. 05), chlorodifluoroethane (ODP=0
．． 06) and dichlorofluoroethane (ODP=
0. By forming a mixture of 1), it is possible to make the effect on the stratospheric ozone layer much smaller than that of R12. It has a vapor pressure similar to that of R12 at temperatures ranging from about 0 to about 50 degrees Celsius, which is the operating temperature of heat bombs, etc., and can provide a working fluid that can be used in current equipment as an alternative to L and R12. The ODP in the above combinations and ranges is 0. 05~0. Expected to be 07 R
However, such a mixture is a non-azeotropic mixture and constitutes a Lorenz cycle in which the temperature gradient between the condensation process and the evaporation process is close to that of the heat source fluid. Examples of working fluids according to the present invention will be described below with reference to the drawings. ), 1
-Chloro-1, l-difluoroethane (R142b
), l, 1-dichloro-1-fluoroethane (R
The working fluid α is composed of a mixture of three types of fluorocarbons (14 lb).The equilibrium state at constant temperature and constant pressure is shown using triangular coordinates. The single substances are arranged counterclockwise in descending order of boiling point from the base point, and the group ratio (weight ratio > ti
t. ．． It can also be expressed as the ratio of the distance between a point and each side of a triangle.
Also, at this time, the distance it between the 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.
．． This is the vapor-liquid equilibrium line of the mixture at 1 1 6 kg/cm"G, and this temperature and pressure correspond to the saturated state of R12. The upper line of vapor-liquid equilibrium line (equivalent to R120°C) 1 is the saturated vapor phase. The lower line of the vapor-liquid equilibrium line (equivalent to R120°C) represents the saturated liquidus line, and the range between these lines is in a state of vapor-liquid equilibrium.The temperature is 50°C.
・This is the vapor-liquid equilibrium line of the mixture at a pressure of 11.373 kg/cm'G, and this temperature and pressure also correspond to the saturated state of R12. %. 0 to about 5
The assembly range ILL is 5% by weight to approximately 45% by weight.
R22, Rl is desirable because it has almost the same vapor pressure as Rl2 at a usage temperature of about 0 to about 50°C.
42b and R14lb each weigh approximately 50 to approximately 90K
O~approximately 50% by weight O~approximately 45% by weight ○DP in a certain range of combinations and sets is 0.
05~0. 07, which is expected to be a very promising working fluid as an alternative to R12.
The working fluid combination and DP at point F1 are shown in Table 1. Points Al to C1 are on the saturated vapor phase line of the vapor-liquid equilibrium line (R12, equivalent to 50°C) 2. Point Fl is on the vapor-liquid equilibrium line (R12, equivalent to 50°C) 2.
It is on the saturated liquid line of 2 (equivalent to 50°C) and is sandwiched between the saturated vapor line of vapor-liquid equilibrium line (equivalent to R120°C) 1 and the saturated liquidus line of vapor-liquid equilibrium line (equivalent to R120°C) 1. Temperature 0℃・Pressure 2. 1 16k
g/cm"G (corresponding to the saturated state of Rl 2), there is a vapor-liquid equilibrium state. Also, point Dl and point El are on the saturated liquid line of the vapor-liquid equilibrium line (corresponding to R12 0°C) l, and there is vapor-liquid equilibrium. It must be within the range between the saturated vapor line of line (R12 equivalent to 50°C) 2 and the saturated liquidus line of vapor-liquid equilibrium line (R12 equivalent to 50°C) 2.
・Pressure 1 1. 3 7 3 kg/cm”G (R
Therefore, under the conditions of the saturated vapor pressure of R12 at 0°C and 50°C, the working fluid with the composition shown in Table 1 is By realizing a saturated state or a vapor-liquid equilibrium state at a usage temperature of about 0 to about 50°C, and operating at the saturated vapor pressure of R12 at the same temperature, it is possible to obtain a condensation temperature and evaporation temperature almost equal to that of R12. Here, the force t explained only about the points on the vapor-liquid equilibrium line (R120℃ equivalent) l or the vapor-liquid equilibrium line (R12 equivalent to 50℃) 2 is inside the points A1 to Fl. Temperature 0℃・Pressure 2.116kg/cm"G
By performing the same operation on a working fluid that has a gas-liquid equilibrium state at a temperature of 50°C and a pressure of 11.373 kg/cm''G (both correspond to the saturated state of R12), approximately 0 to approximately 50 R12 at the operating temperature of °C
However, in this example, the working fluid is composed of a mixture of three types of fluorocarbons. Although it is of course possible to construct the working fluid by a mixture of the above-mentioned fluorocarbons, such a mixture becomes a non-azeotropic mixture, and has a temperature gradient in the condensation and evaporation processes. Although a higher performance coefficient than R12 can be expected by constructing a Lorenz cycle with 3 of fluorocarbons included together
By specifying the range of combinations of more than one species, it is possible to 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. Even if it is possible, (2) L 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 R12. (3) Utilizes the temperature gradient properties of non-azeotropic mixtures. te, R1
Even if it has an effect such that a performance coefficient higher than 2 can be expected.

[Brief explanation of the drawing]

Figure 1 (Constructed by a mixture of three types of fluorocarbons...
・Vapor-liquid equilibrium line (equivalent to R120℃), ...vapor-liquid equilibrium line (
Rl2 equivalent to 50°C).

Claims (2)

[Claims] (1) 45 to 95% by weight of chlorodifluoromethane,
A working fluid containing at least three types of fluorocarbons, 55% by weight or less of chlorodifluoroethane and 45% by weight or less of dichlorofluoroethane. (2) chlorodifluoromethane 50 to 90% by weight or less,
A working fluid containing at least three types of fluorocarbons, 50% by weight or less of chlorodifluoroethane and 45% by weight or less of dichlorofluoroethane.