KR100669091B1 - Near azeotropic mixed refrigerant - Google Patents

Abstract

The present invention relates to a mixed refrigerant used in a vapor compression refrigerator or an air conditioner and a refrigeration system using the same, and more specifically, any one selected from propylene (R1270) and propane (R290) and pentafluoroethane (R125). ) And 1,1,1-trifluoroethane (R143a), or pentafluoroethane with any one selected from 1,1-difluoroethane (R152a) and dimethyl ether (DME). (R125) and a propylene (R1270) is a refrigerant for refrigeration / air conditioning consisting of a mixture of the three-dimensional near-air azeotropic three-way mixed refrigerant having a temperature gradient (TG) when evaporated and a refrigeration system using the same. The mixed refrigerant according to the present invention has an advantage that it can be used like a pure refrigerant without affecting the ozone layer at all.

Refrigerant, freezer, air conditioner, mixed refrigerant, global warming, alternative refrigerant, near-air fuel ratio, pentafluoroethane, 1,1,1-trifluoroethane, propylene, propane, 1,1-difluoroethane, dimethyl ether

Description

Near-air azeotropic three-way mixed refrigerant {NEAR AZEOTROPIC MIXED REFRIGERANT}

1 is a temperature-composition diagram of an azeotropic mixed refrigerant.

2 is a temperature gradient diagram of the R125 / R143a / R1270 three-way mixed refrigerant according to the first embodiment of the present invention.

3 is a temperature gradient diagram of the R125 / R143a / R290 three-way mixed refrigerant according to the second embodiment of the present invention.

4 is a temperature gradient diagram of the R125 / R1270 / R152a three-way mixed refrigerant according to the third embodiment of the present invention.

5 is a temperature gradient diagram of the R125 / R1270 / DME three-way mixed refrigerant according to the fourth embodiment of the present invention.

Figure 6 is a block diagram of a general refrigeration / air conditioner used in the present invention.

Explanation of symbols on the main parts of the drawings

Qc: direction of heat flow in the condenser (refrigerant ℃ air)

Qe: Heat flow direction in the evaporator (air coolant)

TS1: evaporator air inlet temperature, TS7: evaporator air outlet temperature

TS3: condenser air outlet temperature, TS6: condenser air inlet temperature

Evaporator: Compressor: Compressor

Condenser: Condenser, Expansion Valve: Expansion Valve

The present invention relates to a three-way mixed refrigerant and a refrigeration system using the same, which can be widely used in low-temperature freezers and transport refrigerators, domestic air conditioners, commercial chillers, etc., the three-way mixed refrigerant of the present invention is propylene (R1270) and propane (R290) ) Or any one selected from the group selected from pentafluoroethane (R125) and 1,1,1-trifluoroethane (R143a), or 1,1-difluoroethane (R152a) and dimethyl ether It is composed of any one of the group selected as (DME) and pentafluoroethane (R125) and propylene (R1270) characterized in that the temperature gradient (TG) during evaporation is within 3 ℃.

Refrigerant (hereinafter referred to as R) is a working fluid of a refrigeration cycle, which refers to a medium that takes heat away from a low temperature object and transfers heat to a high temperature object. Chlorofluorocarbon (hereinafter referred to as CFC) and Hydrochlorofluorocarbon (hereinafter referred to as HCFC) have been mainly used. Recently, however, the destruction of the stratospheric ozone layer by CFCs and HCFCs has emerged as an important global environmental problem, and therefore the production and use of stratospheric ozone-depleting CFCs and HCFCs is regulated by the Montreal Protocol adopted in 1987. Therefore, most countries around the world are trying to use alternative refrigerants with an ODP of 0.0.

In order for a substance to be useful as a substitute for a conventional refrigerant, it has a coefficient of performance (COP) similar to that of a conventional refrigerant, and thus exhibits a refrigerating effect similar to that of a conventional refrigerant, and also has a vapor pressure similar to that of a conventional refrigerant. Can provide a volumetric capacity similar to that of refrigerants), which makes it possible to manufacture refrigeration / air conditioners without changing compressors or making major modifications. However, the results of the previous studies have shown that in case of replacing the existing refrigerant with pure material, the volume of the replacement refrigerant is different, so it is inevitable to change or largely modify the compressor, and it is difficult to obtain a similar coefficient of performance as the existing refrigerant.

One way to solve this problem is to use a mixed refrigerant. The characteristic of the mixed refrigerant is that the composition coefficient is good to make the coefficient of performance (COP) similar to the existing refrigerant and at the same time give a volume capacity similar to the existing refrigerant, there is an advantage that does not need to modify the compressor. Because of these characteristics, several mixed refrigerants have been proposed in the past few years as a replacement for CFCs and HCFCs.

When mixing two or more pure refrigerants to produce a mixed refrigerant, non-azeotropic refrigerant mixtures (NARMs) or azeotropic refrigerant mixtures (ARMs) may be produced, as shown in FIG. 1. As can be seen, non-azeotropic mixed refrigerants, unlike pure refrigerants, begin to evaporate at a given composition (point ①) and begin to increase in evaporation temperature until the end of evaporation (point ②). This phenomenon is called temperature gradient (TG). In FIG. 1, a bubble line is obtained for all compositions in which bubbles are generated while boiling, and a dew line is obtained for all compositions in which bubbles are generated as gases are condensed. 1), and the composition shown in FIG. 1 is expressed in parts by weight of a refrigerant having a low boiling point, that is, a refrigerant having a high vapor pressure, according to a global standard.

This temperature gradient varies greatly depending on the type and composition of the pure materials constituting the mixed refrigerant. In the case of non-azeotropic mixed refrigerants, if the temperature gradient is large, the composition of the refrigerant changes during phase change, which may make the refrigeration system unstable.If a leak occurs in the refrigeration system, the refrigerant having a high vapor pressure leaks first, resulting in an imbalance due to composition separation in the system. Also, there is a problem in that the heat transfer coefficient is increased due to a decrease in heat transfer coefficient due to a large temperature gradient. Therefore, most refrigerant companies are trying to make near azeotropic refrigerant mixtures with a temperature gradient (TG) of less than 3 ° C. For example, in DuPont and Honeywell, USA, the azeotropic mixed refrigerant called R570A (50% R125 / 50% R143a, TG = 0.0 ℃) and the aerosol mixed refrigerant called R410A (50% R32 / 50% R125, TG = 0.2 ℃ Develop and sell. In addition, these companies had previously developed and sold non-azeotropic mixed refrigerants such as R407C, but the temperature gradient of R407C is 7 ℃, so that the composition separation occurs when there is a leak in the system. Only the refrigerant is being developed.

Therefore, the present invention has been made to solve the above problems of the prior art, the object of the present invention is the Ozone Depletion Index (ODP) is 0.0 so that it can be used as a conventional pure refrigerant without any effect on the ozone layer in the stratosphere. It is to provide a new near azeotropic ternary mixed refrigerant and a refrigeration / air conditioner using the refrigerant.

An object of the present invention described above is refrigeration / mixed with any one of the group selected from propylene (R1270) and propane (R290) and pentafluoroethane (R125) and 1,1,1-trifluoroethane (R143a) As the refrigerant for the air conditioner can be achieved by the near-azeotropic ternary mixed refrigerant, characterized in that the temperature gradient (TG) during evaporation within 3 ℃.

Three-way mixed refrigerant for achieving the above object is 0.1 to 99.8 parts by weight of pentafluoroethane (R125), 0.1 to 99.8 parts by weight of 1,1,1-trifluoroethane (R143a) and 0.1 to 99.8 parts by weight of propylene (R1270). It is preferably composed of 99.8 parts by weight.

Three-way mixed refrigerant for achieving the above object is 0.1 to 99.8 parts by weight of pentafluoroethane (R125), 0.1 to 99.8 parts by weight of 1,1,1-trifluoroethane (R143a) and 0.1 to 99.8 parts by weight of propane (R290). Among 99.8 parts by weight, it is preferable that the temperature gradient is constituted by a predetermined part by weight within 3 ° C.

The object of the present invention described above is a refrigeration mixture of pentafluoroethane (R125) and propylene (R1270) with any one selected from 1,1-difluoroethane (R152a) and dimethyl ether (DME or RE170). It can be achieved by the near-azeotropic ternary mixed refrigerant, characterized in that the temperature gradient (TG) at the time of evaporation as a refrigerant for the air conditioner.

Three-way mixed refrigerant to achieve the above object is pentafluoroethane (R125) 0.1 to 99.8 parts by weight, propylene (R1270) 0.1 to 99.8 parts by weight and 1,1-difluoroethane (R152a) 0.1 to 42 weight It is preferable that it consists of parts.

The three-way mixed refrigerant for achieving the above object is preferably composed of 0.1 to 99.8 parts by weight of pentafluoroethane (R125), 0.1 to 99.8 parts by weight of propylene (R1270) and 0.1 to 34 parts by weight of dimethyl ether (DME). .

The above object of the present invention can be achieved by using any one selected from the group consisting of the above-mentioned refrigerants as the operating refrigerant of the refrigerating / air conditioner.

Other objects, specific advantages, and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments associated with the accompanying drawings.

Hereinafter, with reference to the accompanying drawings, it will be described in detail with respect to the configuration of a near azeotropic three-way mixed refrigerant and a refrigeration system using the same according to an embodiment of the present invention.

The present invention relates to a three-way mixed refrigerant and a refrigeration system using the same, which can be widely used in low-temperature freezers and transport refrigerators, domestic air conditioners, commercial chillers, etc., the three-way mixed refrigerant of the present invention is propylene (R1270) and propane (R290) ), Pentafluoroethane (R125) and 1,1,1-trifluoroethane (R143a) or a mixture of 1,1-difluoroethane (R152a) and dimethyl It is composed by mixing any one of the group selected as ether (DME) and pentafluoroethane (R125) and propylene (R1270) is a temperature gradient (TG) when evaporation is within 3 ℃.

It is an object of the present invention to provide a near azeotropic ternary mixed refrigerant that can be used like a conventional pure refrigerant without affecting the ozone layer in the stratosphere because the ODP is 0.0.

In order to develop a near azeotropic alternative mixed refrigerant, the present inventors use the refrigerant state equation developed by the National Institute of Standards and Technology (NIST) to simulate the performance of refrigeration and air conditioning. Bubble Point and the dew point at which the gas condenses to produce the dew point were calculated and a temperature gradient diagram of the near azeotropic ternary mixed refrigerant was made. The Carnahan-Starling-De Santis (CSD) refrigerant state equation, commonly known as PEFPROP, was developed by the National Institute of Standards and Technology (NIST) and has been proven to be the most accurate and applicable in the world of leading refrigeration and air conditioning companies, research institutes and universities. It is a widely used program.

The present inventors have determined that the mixed refrigerant of the present invention is an alternative refrigerant for refrigeration / air conditioning, and the ozone depletion index (ODP) must be 0.0. R125 (Pentafluoroethane, pentafluoroethane), R143a (1,1,1-Trifluoroethane, 1 , 1,1-trifluoroethane), R1270 (Propylene, propylene), R290 (Propane, propane), R152a (1,1-Difluoroethane, 1,1-difluoroethane) and DME (or RE170) (Dimethyl We have developed a near azeotropic ternary mixed refrigerant that does not have to worry about destroying the ozone layer formed by mixing ether and dimethyl ether.

[Composition table according to an embodiment of the present invention] Example Furtherance Composition ratio (weight% = weight part) One R125 / R143a / R1270 R125 R143a R1270 0.1 to 99.8 0.1 to 99.8 0.1 to 99.8 2 R125 / R143a / R290 R125 R143a R290 0.1 to 99.8 0.1 to 99.8 0.1 to 99.8 3 R125 / R1270 / R152a R125 R1270 R152a 0.1 to 99.8 0.1 to 99.8 0.1-42 4 R125 / R1270 / DME R125 R1270 DME 0.1 to 99.8 0.1 to 99.8 0.1 to 34

[Table 1] is a table showing the composition and composition ratio of the three-way mixed refrigerant according to an embodiment of the present invention.

2 to 5 show a temperature gradient diagram of the near azeotropic ternary mixed refrigerants developed by the present inventors. Unlike the two-way refrigerant, when the three-way refrigerant changes three components, it is difficult to draw a temperature-composition diagram as shown in Figure 1, so the present inventors draw contours representing the same temperature gradient as shown in Figures 2 to 5 In any combination, the temperature gradients of the three-way mixed refrigerants were known.

[Example 1 of the present invention]

2 is a diagram showing a temperature gradient diagram of the R125 / R143a / R1270 three-way mixed refrigerant according to the first embodiment of the present invention. Referring to Figure 2, the three-way mixed refrigerant according to the first embodiment of the present invention is a composition of R125 (pentafluoroethane), R143a (1,1,1-trifluoroethane) and R1270 (propylene) Even when mixed as can be seen that the temperature gradient (TG) is less than 1.6 ℃. Therefore, the R125 / R143a / R1270 ternary mixed refrigerant can be treated similarly to pure refrigerant as a near azeotropic refrigerant.

[Example 2 of the present invention]

3 is a diagram showing a temperature gradient diagram of the R125 / R143a / R290 three-way mixed refrigerant according to the second embodiment of the present invention. Referring to FIG. 3, the three-way mixed refrigerant according to the second embodiment of the present invention shows that the temperature gradient is 3 ° C. or less in a predetermined region of the range of 0.1 to 99.8 parts by weight of R125, R143a, and R290, respectively. For example, in the case of a mixed refrigerant having a composition of R125 of 20 parts by weight, a composition of R143a of 50 parts by weight, and a composition of R290 (propane) of 30 parts by weight, a temperature gradient of about 1 ° C. results in a near azeotropic mixed refrigerant. . However, even when R32 is 20 parts by weight, there is a significant difference in temperature gradient of about 6 ° C when R143a is 10 parts by weight and R290 is 70 parts by weight. Therefore, the R125 / R143a / R290 ternary mixed refrigerant can be treated like a pure refrigerant when it has a composition ratio belonging to the near azeotropic mixed refrigerant region (shown in FIG. 3) having a temperature gradient of 3 ° C or lower. As used herein, parts by weight means weight percent.

[Example 3 of the present invention]

4 is a diagram showing a temperature gradient diagram of the R125 / R1270 / R152a three-way mixed refrigerant according to the third embodiment of the present invention. Referring to Figure 4, the three-way mixed refrigerant according to the third embodiment of the present invention is a predetermined region of 0.1 to 99.8 parts by weight of the composition of R125 and R1270 and 0.1 to 42 parts by weight of the composition of R152a (indicated in Figure 4 Part) and may be mixed with a near azeotropic mixed refrigerant whose temperature gradient does not exceed 3 ° C. For example, when R125 is 50 parts by weight, R1270 is 40 parts by weight and R152a is 10 parts by weight, the temperature gradient is 2 ° C. Therefore, the R125 / R1270 / R152a ternary mixed refrigerant can be treated like a pure refrigerant. However, it can be seen that the temperature gradient rises sharply when it is out of the near azeotropic mixed refrigerant zone. Even though R125 is 50 parts by weight, when R1270 is 19 parts by weight and R152a is 31 parts by weight, the temperature gradient is 8 ° C. However, a mixed refrigerant having such a composition cannot be treated like a pure refrigerant because of a large change in composition during phase change or refrigerant leakage.

[Example 4 of the present invention]

5 is a diagram showing a temperature gradient diagram of the R125 / R1270 / DME ternary mixed refrigerant according to the fourth embodiment of the present invention. Referring to Figure 5, the three-way mixed refrigerant according to the fourth embodiment of the present invention is a temperature in a predetermined region of the region of the composition of R125 and R1270 of 0.1 to 99.8 parts by weight and DME of 0.1 to 34 parts by weight, respectively The gradient is shown to be 3 degrees C or less. For example, in the case of a mixed refrigerant having a composition of R125 of 30 parts by weight, a composition of R1270 of 60 parts by weight, and a composition of DME (dimethyl ether) of 10 parts by weight, the temperature gradient is 2 ° C., resulting in a near azeotropic mixed refrigerant. However, even when R125 is 30 parts by weight, there is a significant difference in temperature gradient of about 8 ° C. when R1270 is 31 parts by weight and DME is 39 parts by weight. Therefore, when the composition ratio of the R125 / R1270 / DME ternary mixed refrigerant falls within the near azeotropic mixed refrigerant region (shown in FIG. 5) having a temperature gradient of 3 ° C. or less, it can be treated like a pure refrigerant.

Figure 6 is a block diagram of a general refrigeration / air conditioner used in the present invention. As shown in FIG. 6, the refrigeration / air conditioner generally comprises an evaporator, a condenser, a compressor, an expansion valve, and the like. When the near azeotropic ternary mixed refrigerants according to Embodiments 1 to 4 of the present invention are used, there is no change in the composition and heat transfer coefficients in spite of leakage of the refrigerant as in the case of using a general pure refrigerant. It has the advantage that it can be used without modifying the air conditioner.

It is to be noted that the term "refrigeration system" used throughout the specification of the present invention is used in the meaning of a refrigerator / air conditioner, unless otherwise specified, that both are used in the same meaning.

According to the mixed refrigerant and the refrigeration system using the same according to the preferred embodiment of the present invention having the above-described configuration, since the ozone layer destruction index of the material constituting the mixed refrigerant is 0.0, even when the refrigerant flows out or discards the refrigerant, There is a significant effect that can be prevented.

In addition, since the mixed refrigerant according to the present invention is a three-way mixed refrigerant constituting the near-air ratio, there is no change in composition according to the phase change, so that the refrigeration system can be used stably as in the case of using pure refrigerant, and the composition is separated when the refrigerant flows out. There is a significant effect that the phenomenon is prevented.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as fall within the spirit of the invention.

Claims (2)

delete 1,1-difluoroethane (R152a) and dimethyl ether (DME or RE170) of any one selected from the group mixed with pentafluoroethane (R125) and propylene (R1270), the temperature gradient during evaporation is 3 ℃ Among the refrigerants for refrigeration and air conditioning that are within Pentafluoroethane (R125) 0.1 to 99.8 parts by weight, propylene (R1270) 0.1 g 99.8 parts by weight and dimethyl ether (DME) 0.1 to 34 parts by weight of the azeotropic three-way mixed refrigerant, characterized in that consisting of.

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