JP2536545B2 - Working medium mixture - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel working medium mixture that can be used in refrigerators, heat pumps, and the like.

[Prior art] Air conditioning, refrigeration and refrigeration equipment (refrigeration cycle / heat pump cycle), waste heat recovery power generation (rankin cycle),
Heat exchange equipment (heat pipes) and the like have been commercialized or tested and developed. The working medium used for these devices includes water, hydrocarbons such as propane and butane, trichlorofluoromethane (R11), and chlorodifluoromethane (R2
2) and the like, or ammonia and the like are known.

[Problems to be Solved by the Invention] CFCs are less toxic, non-flammable and chemically stable, and various CFCs with different standard boiling points are easily available. Has been done to. The present invention newly provides CFCs having a high heat recovery efficiency, in particular, a freezer, a refrigerator, a cooling / heating device, an oil supply device, or a heat pump system for the purpose of recovering waste heat.

[Means for Solving Problems] The present invention relates to a working medium mixture containing pentafluoroethane (hereinafter abbreviated as R125) and monochlorotetrafluoroethane as essential components.

Monochlorotetrafluoroethane in the present invention includes 1-chloro-1,2,2,2-tetrafluoroethane (R12
4) and 1-chloro-1,1,2,2-tetrafluoroethane (R1
Two types of isomers of 24a) are known, but since they have similar physical properties, they may be used alone, or a mixture thereof may be used. In the following description, an example in which R125 and R124 are mixed and used is shown.

Hereinafter, the present invention will be described in detail with reference to FIG. 1 showing a flow sheet of a refrigeration cycle system using the working medium mixture of the present invention (hereinafter, simply referred to as a working medium). In FIG. 1, 1 is a compressor, 2 is a condenser, 3 and 3'are load fluid pipes, 4 is a pressure reducing device, 5 is an evaporator, and 6 and 6'are heat source fluid pipes.

In the refrigeration cycle system shown in FIG. 1, the working medium mixture is compressed by the compressor 1 and then guided to the condenser 2,
In the condenser 2, the load fluid introduced from the pipe 3 cools and condenses. On the other hand, the load fluid is inversely heated in the condenser 2 and supplied to the load heating through the pipe 3 '. Next, the condensed working medium is decompressed by the decompression device 4 and then evaporated.
And is heated by the heat source fluid introduced into the evaporator 5 through the pipe 6 and discharged through the pipe 6 ′ in the evaporator 5, and then the compressor 1 again.
And the above cycle is repeated. On the other hand, the heat source fluid is inversely cooled in the evaporator 5 and is cooled by the pipe 6 '.

FIGS. 2 and 3 show the cycle of the working medium mixture in the refrigeration cycle system shown in FIG. 1 plotted on the pressure-enthalpy diagram. FIG. 2 shows a state in which when the saturated steam of the working medium is adiabatically compressed, it becomes wet.
FIG. 3 shows a dry state.

The change of the working medium by the compressor in FIG. 1 is the change from 8 to 9 or 13 to 14 in FIGS. 2 and 3, and the change of the working medium by the condenser is 9 → 10 → 11 → or 14 → 15. →
The change of the working medium by the pressure reducing device corresponds to the change of 11 to 12 or 17 to 18, and the change of the working medium by the evaporator corresponds to the change of 12 to 8 or 18 to 13, respectively.

The operating conditions of the refrigeration cycle system of FIG. 1 using the working medium mixture of the present invention are as follows: The temperature at the start of condensation (the temperature of code 9 or 15; hereinafter referred to as the condensation temperature) was set. Tables 1 to 2 show the coefficient of performance and the refrigerating capacity per unit compressor KW in the above refrigeration cycle system using the working medium mixture of the present invention together with comparative examples.

As can be understood from the table, the mixing molar ratio of R125 and R124 is
The range of 1:99 to 99: 1, especially the range of 1:99 to 40:60 The coefficient of performance and refrigerating capacity of the refrigeration cycle using the working medium mixture of the present invention are R125 and R124, respectively. It has been improved compared to the case where it was, especially R125 and R124
When using the working medium mixture of the present invention in which the mixing molar ratio with is about 20:80, a high improvement effect is obtained.

The working medium mixture of the present invention is particularly effective when applied to a refrigeration cycle for the purpose of air conditioning, freezing and refrigeration in the low to high temperature field, but is also used as a working medium for various other heat recovery technologies such as Rankine cycle. You can also The working medium mixture of the present invention has excellent thermal stability,
No stabilizer is required under normal use conditions, but when heat stability is required to be improved due to severe use conditions,
Dimethyl phosphite, diisopropyl phosphite,
A phosphite compound such as diphenylphosphite, or a thiophosphite compound, or a phosphine sulfide compound such as triphenoxyphosphine sulfide and trimethylphosphine sulfide, and other stabilizers such as glycidyl ethers per 100 parts by weight of the refrigerant, It may be added in a small amount of about 1 part by weight.

[Effects of the Invention] The working medium mixture of the present invention is particularly excellent in refrigeration cycle efficiency, that is, refrigeration and heating efficiency, and is significantly improved as compared with a single component before mixing.

[Brief description of drawings]

FIG. 1 is a flow chart of a refrigeration cycle for explaining one embodiment of the present invention, and FIGS. 2 and 3 are pressure-enthalpy diagrams in which a cycle using a R125 / R124 mixed system as a working medium is entered. It is a figure.

Claims (2)

(57) [Claims] 1. A working medium mixture comprising pentafluoroethane and monochlorotetrafluoroethane as essential components. 2. The working medium mixture according to claim 1, wherein the mixing molar ratio of pentafluoroethane and monochlorotetrafluoroethane is 1:99 to 99: 1.