Mixed refrigerant composition and heat pump comprising same

Abstract

A mixed refrigerant composition according to exemplary embodiments may comprise carbon dioxide (R-744), (2,3,3,3-tetrafluoropropene (R-1234yf) and 1,1-difluoroethane (R-152a). The amount of carbon dioxide (R-744) can be 1-10 wt% on the basis of the total weight of the mixed refrigerant composition, the amount of 2,3,3,3-tetrafluoropropene (R-1234yf) can be 65-95 wt% on the basis of the total weight of the mixed refrigerant composition, and the amount of 1,1-difluoroethane (R-152a) can be 1-30 wt% on the basis of the total weight of the mixed refrigerant composition. The boiling point of the mixed refrigerant composition at 1 atm can be between -65 °C and -30 °C.

Description

Mixed refrigerant composition and heat pump comprising the same

[0001] The present invention relates to a composition containing a refrigerant and a heat pump containing the same.

[0002]

[0003] A refrigerant is a substance used to remove heat from heat pumps, such as those used in air conditioners, refrigerators, and cooling towers. Examples of refrigerants include natural refrigerants, chlorofluorocarbon (CFC) refrigerants, hydrochlorofluorocarbon (HCFC) refrigerants, hydrofluorocarbon (HFC) refrigerants, and hydrofluoroolefin (HFO) refrigerants.

[0004] In recent years, the types of heat pumps used indoors and outdoors have diversified, and the development of electric vehicles and other technologies has led to a demand for smaller heat pumps. Furthermore, refrigerants containing chlorine (Cl) can contribute to ozone layer destruction, so efforts are underway to develop refrigerants that do not contain chlorine atoms.

[0005] For example, 2,3,3,3-tetrafluoropropane (R-1234yf), a type of hydrofluoroolefin refrigerant, does not contain chlorine atoms. Therefore, it has a low global warming potential (GWP), and is actively used as a refrigerant in automobile air conditioners.

[0006] However, 2,3,3,3-tetrafluoropropene has a low coefficient of performance (COP), so when used as a refrigerant in automobile air conditioners, an additional heat pump is required, which has the problem of low energy efficiency.

[0007] Therefore, there is a need to develop a refrigerant or combination of refrigerants that can suppress environmental pollution while also having a high coefficient of performance.

[0008]

[0009] One object of the present invention is to provide a mixed refrigerant composition having improved environmental friendliness.

[0010] One object of the present invention is to provide a heat pump having improved cooling performance, comprising the above mixed refrigerant composition.

[0011]

[0012] According to embodiments of the present disclosure, a mixed refrigerant composition includes carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf), and 1,1-difluoroethane (R-152a). The content of the carbon dioxide (R-744) is 1 wt% to 10 wt% of the total weight of the mixed refrigerant composition, the content of the 2,3,3,3-tetrafluoropropene (R-1234yf) is 65 wt% to 95 wt% of the total weight of the mixed refrigerant composition, and the content of the 1,1-difluoroethane (R-152a) is 1 wt% to 30 wt% of the total weight of the mixed refrigerant composition. The boiling point of the above mixed refrigerant composition at 1 atm is -65°C to -30°C.

[0013] A mixed refrigerant composition according to exemplary embodiments may be composed of the carbon dioxide (R-744), the 2,3,3,3-tetrafluoropropene (R-1234yf), and the 1,1-difluoroethane (R-152a).

[0014] According to exemplary embodiments, the content of the 1,1-difluoroethane (R-152a) may be from 13 wt% to 25 wt% of the total weight of the mixed refrigerant composition.

[0015] According to exemplary embodiments, the content of the 1,1-difluoroethane (R-152a) may be 18 wt% to 23 wt% of the total weight of the mixed refrigerant composition.

[0016] According to exemplary embodiments, the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be from 6 to 95.

[0017] According to exemplary embodiments, the ratio of the content of 1,1-difluoroethane (R-152a) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be from 0.5 to 30.

[0018] According to exemplary embodiments, the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of 1,1-difluoroethane (R-152a) in the total weight of the mixed refrigerant composition may be from 2 to 19.

[0019] According to exemplary embodiments, the critical temperature of the mixed refrigerant composition may be 90° C. to 100° C.

[0020] According to exemplary embodiments, the critical pressure of the mixed refrigerant composition may be 30 bar to 51 bar.

[0021] According to exemplary embodiments, the temperature glide of the mixed refrigerant composition at a pressure of 1.5 bar may be from 3° C. to 29° C.

[0022] According to exemplary embodiments, the temperature glide of the mixed refrigerant composition at a pressure of 15 bar may be from 2° C. to 23° C.

[0023] According to exemplary embodiments, the latent heat of the mixed refrigerant composition at -25°C may be from 150 kJ / kg to 250 kJ / kg.

[0024] According to exemplary embodiments, the global warming potential (GWP) of the mixed refrigerant composition may be from 1 to 40.

[0025] A heat pump according to embodiments of the present disclosure comprises the mixed refrigerant composition.

[0026]

[0027] According to exemplary embodiments, the mixed refrigerant composition may not contain chlorine atoms (Cl) in the refrigerant included in the mixed refrigerant composition, so that environmental pollution such as ozone layer destruction may be suppressed.

[0028] The mixed refrigerant composition according to exemplary embodiments can effectively lower the ambient temperature while vaporizing from a liquid to a gas even at low temperatures.

[0029] Additionally, the mixed refrigerant composition may not undergo a phase transformation to a supercritical state while a refrigerant, such as an air conditioner, is operating. Accordingly, the condensing pressure of the compressor may not be lowered, and the performance coefficient of a heat pump including the mixed refrigerant composition may be improved.

[0030]

[0031] Figures 1 and 2 are schematic diagrams showing the flow of mixed refrigerant for heat exchange in cooling mode or heating mode of a heat exchanger according to exemplary embodiments, respectively.

[0032]

[0033] According to exemplary embodiments, a mixed refrigerant composition comprising carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf) and 1,1-difluoroethane (R-152a) and a heat pump comprising the mixed refrigerant composition are provided.

[0034] Below, the present disclosure will be described in detail. However, this is merely exemplary and the present disclosure is not limited to the specific embodiments described as examples.

[0035] According to exemplary embodiments, the refrigerants included in the mixed refrigerant composition may be refrigerants that do not contain chlorine atoms (Cl). Examples of refrigerants that do not contain chlorine atoms (Cl) include natural refrigerants, hydrofluorocarbon (HFC)-based refrigerants, and hydrofluoroolefin (HFO)-based refrigerants.

[0036] The above natural refrigerant is a substance that exists naturally on Earth, not an artificial compound. The above natural refrigerant may include, for example, at least one of ammonia (R-717), carbon dioxide (R-744), propane (R-290), propylene (R-1270), and butane (R-600a).

[0037] The above hydrofluorocarbon (HFC) refrigerant is a refrigerant composed of hydrogen atoms (H), fluorine atoms (F), and carbon atoms (C). The above hydrofluorocarbon (HFC) refrigerants include, for example, difluoromethane (R-32), trifluoroiodomethane (R-13I1), 1,1-difluoroethane (R-152a), pentafluoroethane (R-125), 1,1,1-trifluoroethane (R-143a), trifluoromethane (R-23), fluoroethane (R-161), 1,1,1,2,3,3,3-heptafluoropropane (R-227ea), 1,1,1,2,3,3-hexafluoropropane (R-236ea), 1,1,1,3,3,3-hexafluoropropane (R-236fa), 1,1,1,3,3-pentafluoropropane (R-245fa), and 1,1,1,3,3-pentafluorobutane (R-365mfc). At least one of them may be included.

[0038] The above hydrofluoroolefin (HFO) refrigerant is a refrigerant composed of hydrogen atoms (H), fluorine atoms (F), and carbon atoms (C), and having at least one double bond between the carbon atoms. The hydrofluoroolefin (HFO) refrigerant may include, for example, at least one of 1,1,2-trifluoroethylene (R-1123), 2,3,3,3-tetrafluoropropene (R-1234yf), 1,3,3,3-tetrafluoropropene (R-1234ze), 1,2,3,3-tetrafluoropropene (R-1234ye), 3,3,3-trifluoropropene (R-1243zf), 1,1-difluoroethylene (R-1132a), and 1,2,3,3,3-pentafluoropropene (R-1225ye).

[0039] A mixed refrigerant composition according to embodiments of the present disclosure comprises carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf), and 1,1-difluoroethane (R-152a). The carbon dioxide (R-744), the 2,3,3,3-tetrafluoropropene (R-1234yf), and the 1,1-difluoroethane (R-152a) included in the mixed refrigerant composition do not contain a chlorine atom (Cl).

[0040] The above carbon dioxide (R-744) is a type of natural refrigerant, and has an ozone depleting potential (ODP) of 0 and a global warming potential (GWP) of 1. In addition, the above carbon dioxide (R-744) may not be corrosive, toxic, explosive, etc. The carbon dioxide (R-744) may be included in the mixed refrigerant composition, thereby improving the environmental friendliness and stability of the mixed refrigerant composition.

[0041] The above 2,3,3,3-tetrafluoropropene (R-1234yf) is a type of hydrofluoroolefin (HFO) refrigerant, and has an ozone depletion potential (ODP) of 0 and a global warming potential (GWP) of 4 or less. In addition, the R-1234yf may have high thermal stability and a high latent heat of vaporization. The 2,3,3,3-tetrafluoropropene (R-1234yf) may be included in the mixed refrigerant composition to improve the environmental friendliness, thermal stability, and refrigeration capacity of the mixed refrigerant composition.

[0042] The above 1,1-difluoroethane (R-152a) is a type of hydrofluorocarbon (HFC) refrigerant, has an ozone depletion potential (ODP) of 0, and a global warming potential (GWP) of 150 or less. In addition, the 1,1-difluoroethane (R-152a) may have a low molecular weight and saturation density. When the 1,1-difluoroethane (R-152a) is included in the mixed refrigerant composition, the environmental friendliness of the mixed refrigerant composition may be improved. In addition, since the discharge pressure in the compressor may be low due to the low saturation density, the enthalpy change at the same compression ratio may increase. Accordingly, the refrigerating capacity of the mixed refrigerant composition may be improved.

[0043] In some embodiments, the mixed refrigerant composition may not contain any refrigerants other than carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf), and 1,1-difluoroethane (R-152a). For example, the mixed refrigerant composition may not contain any additional hydrofluorocarbon (HFC) refrigerants, such as difluoromethane (R-32), which have a high global warming potential. Accordingly, the environmental friendliness of the mixed refrigerant composition may be improved. For example, the mixed refrigerant composition may not contain any additional hydrofluoroolefin (HFO) refrigerants, such as 1,1-difluoroethylene (R-1132a), which are toxic. Accordingly, safety may be improved even if some of the mixed refrigerant composition leaks from the heat pump.

[0044] For example, the mixed refrigerant composition may be composed solely of carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf), and 1,1-difluoroethane (R-152a). Accordingly, it is possible to prevent refrigerants with low thermal and / or chemical stability from being mixed, resulting in a decrease in thermal and / or chemical stability. In addition, it is possible to prevent refrigerants with low vapor pressure from being mixed, resulting in an increase in condensation temperature, or refrigerants with low latent heat of vaporization from being mixed, resulting in a decrease in refrigerating capacity.

[0045] According to exemplary embodiments, the content of the carbon dioxide (R-744) may be 1 wt% to 10 wt%, 1 wt% to 8 wt%, 1 wt% to 6 wt%, or 1 wt% to 5 wt% of the total weight of the mixed refrigerant composition. When the content of the carbon dioxide (R-744) is less than 1 wt% of the total weight of the mixed refrigerant composition, the global warming potential (GWP) of the mixed refrigerant composition may increase. Accordingly, the environmental friendliness may be reduced. When the content of the carbon dioxide (R-744) exceeds 10 wt% of the total weight of the mixed refrigerant composition, the refrigerating capacity of the mixed refrigerant composition may be reduced. Accordingly, the cooling characteristics of the mixed refrigerant composition may be reduced. Above the content, the global warming potential (GWP) of the mixed refrigerant composition may be reduced without reducing the refrigeration performance. Accordingly, the environmental friendliness and cooling characteristics of the mixed refrigerant composition may be improved.

[0046] In some embodiments, the content of the carbon dioxide (R-744) may be from 1.5 wt% to 5 wt%, from 2 wt% to 5 wt%, from 3 wt% to 5 wt%, or from 4 wt% to 5 wt%, or from 4.5 wt% to 5 wt% of the total weight of the mixed refrigerant composition. Within the above content range, the environmental friendliness and cooling characteristics of the mixed refrigerant composition may be further improved.

[0047] According to exemplary embodiments, the content of 2,3,3,3-tetrafluoropropene (R-1234yf) may be from 65 wt% to 95 wt%, from 70 wt% to 95 wt%, or from 70 wt% to 90 wt%, or from 75 wt% to 90 wt% of the total weight of the mixed refrigerant composition. When the content of 2,3,3,3-tetrafluoropropene (R-1234yf) is less than 65 wt% of the total weight of the mixed refrigerant composition, the content of 1,1-difluoroethane (R-152a) may increase, thereby deteriorating thermal stability. In addition, the content of carbon dioxide (R-744) may increase, thereby deteriorating cooling capacity. When the content of the above 2,3,3,3-tetrafluoropropene (R-1234yf) exceeds 95 wt% of the total weight of the mixed refrigerant composition, the content of 1,1-difluoroethane (R-152a) may decrease, resulting in a decrease in cooling capacity. Within the above content range, the thermal stability, cooling capacity, and environmental friendliness of the mixed refrigerant composition may be improved.

[0048] In some embodiments, the content of 2,3,3,3-tetrafluoropropene (R-1234yf) may be from 75 wt% to 90 wt%, from 75 wt% to 89 wt%, from 75 wt% to 88 wt%, or from 75 wt% to 87 wt%, or from 75 wt% to 85 wt% of the total weight of the mixed refrigerant composition. Within this content range, the thermal stability and refrigerating capacity of the mixed refrigerant composition may be further improved.

[0049] According to exemplary embodiments, the content of the 1,1-difluoroethane (R-152a) may be 1 wt% to 30 wt%, 3 wt% to 30 wt%, or 5 wt% to 30 wt% of the total weight of the mixed refrigerant composition. When the content of the 1,1-difluoroethane (R-152a) is less than 1 wt% of the total weight of the mixed refrigerant composition, the refrigeration capacity may be reduced. When the content of the 1,1-difluoroethane (R-152a) is more than 30 wt% of the total weight of the mixed refrigerant composition, the global warming potential (GWP) value may increase. Accordingly, the environmental friendliness of the mixed refrigerant composition may be reduced. Within the above range, the environmental friendliness of the mixed refrigerant composition may be increased while the cooling capacity may be improved.

[0050] In some embodiments, the content of the 1,1-difluoroethane (R-152a) may be 10 wt% to 30 wt%, 10 wt% to 25 wt%, 13 wt% to 25 wt%, 15 wt% to 25 wt%, or 15 wt% to 23 wt%, or 18 wt% to 23 wt% of the total weight of the mixed refrigerant composition. In the above content range, the environmental friendliness of the mixed refrigerant composition may be increased while the cooling capacity may be further improved, and the latent heat of vaporization of the mixed refrigerant composition may be further increased. Accordingly, the freezing capacity may be further increased.

[0051] In some embodiments, the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 6 to 95, 6 to 90, 10 to 85, 10 to 80, or 13 to 80. In this range, the thermal stability, environmental friendliness, and refrigeration capacity of the mixed refrigerant composition may be improved.

[0052] In one embodiment, the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 13 to 60, 13 to 45, 13 to 40, 13 to 35, 13 to 30, or 13 to 25, or 13 to 20, or 13 to 18. In this range, the thermal stability, environmental friendliness, and refrigeration capacity of the mixed refrigerant composition may be further improved.

[0053] In some embodiments, the ratio of the content of 1,1-difluoroethane (R-152a) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 0.5 to 30, 1 to 25, 1 to 20, or 1 to 15. In this range, the cooling capacity of the mixed refrigerant composition may be improved.

[0054] In one embodiment, the ratio of the content of 1,1-difluoroethane (R-152a) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition may be 1 to 15, 1 to 10, 1 to 7, or 1 to 6. In this range, the cooling capacity of the mixed refrigerant composition may be further improved.

[0055] In some embodiments, the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of 1,1-difluoroethane (R-152a) in the total weight of the mixed refrigerant composition may be 2 to 19, 2 to 18, 2 to 15, 2 to 10, 3 to 10, 3 to 9, or 3 to 6. In this range, thermal stability and refrigeration capacity may be improved.

[0056] In one embodiment, the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of 1,1-difluoroethane (R-152a) in the total weight of the mixed refrigerant composition may be 3.5 to 6, 3.5 to 5.5, 3.5 to 5.4, 3.5 to 5, or 3.5 to 4. In this range, the thermal stability and refrigeration capacity of the mixed refrigerant composition may be further improved.

[0057] According to exemplary embodiments, the boiling point of the mixed refrigerant composition at 1 atm can be from -65 °C to -30 °C, from -60 °C to -30 °C, from -55 °C to -34 °C, or from -55 °C to -40 °C.

[0058] When the boiling point of the mixed refrigerant composition is lower than -65°C, the condensation pressure may increase at the condensation temperature of the mixed refrigerant composition. Accordingly, the energy consumed in the refrigeration cycle may increase, thereby reducing the efficiency of the refrigerant.

[0059] When the boiling point of the mixed refrigerant composition exceeds -30°C, the specific volume may increase at the condensation temperature of the mixed refrigerant composition. Accordingly, the amount of the mixed refrigerant composition required to improve the refrigerating capacity may increase, thereby increasing the volume of the air conditioner.

[0060] In some embodiments, the boiling point of the mixed refrigerant composition at 1 atm may be -55°C to -45°C, -53°C to -45°C, or -53°C to -48°C. Within this boiling point range of the mixed refrigerant composition, the specific volume may be reduced without increasing the condensing pressure. Accordingly, the refrigerant's refrigerant cooling capacity may be improved while reducing the amount of the mixed refrigerant composition.

[0061] In some embodiments, the critical temperature of the mixed refrigerant composition may be 90° C. to 100° C., 95° C. to 100° C., 97° C. to 100° C., or 97° C. to 99° C. The critical temperature is the maximum temperature at which a specific substance can exist in a liquid state. If the critical temperature of the refrigerant is low, liquefaction of the refrigerant may be difficult during the condensation process during the refrigeration cycle.

[0062] Within the above critical temperature range, the mixed refrigerant composition may not enter a supercritical fluid state during the refrigeration cycle. Therefore, a portion of the mixed refrigerant composition may be prevented from entering a supercritical fluid state and not being liquefied, thereby improving refrigeration capacity.

[0063] In some embodiments, the critical pressure of the mixed refrigerant composition may be 30 bar to 51 bar, 30 bar to 50 bar, 35 bar to 50 bar, 35 bar to 45 bar, 39 bar to 45 bar, or 40 bar to 45 bar. The critical pressure is the maximum pressure at which a specific substance can exist in a liquid state, and if the critical pressure of the refrigerant is high, liquefaction of the refrigerant may be difficult in the refrigeration cycle.

[0064] Within the above critical pressure range, the mixed refrigerant composition may not become a supercritical fluid state in the refrigeration cycle. Accordingly, a portion of the mixed refrigerant composition may be prevented from liquefying, thereby improving refrigeration capacity.

[0065] In some embodiments, the temperature glide of the mixed refrigerant composition at a pressure of 1.5 bar may be 3° C. to 29° C., 3° ​​C. to 28° C., 8° C. to 27° C., 10° C. to 26° C., 11° C. to 26° C., 11° C. to 25° C., 11° C. to 20° C., or 15° C. to 20° C. In the temperature glide range, composition separation may not occur even if the mixed refrigerant leaks. Accordingly, the usable capacity of the mixed refrigerant composition may be improved even when a heat pump of the same volume is used.

[0066] In some embodiments, the temperature glide of the mixed refrigerant composition at a pressure of 15 bar may be 2° C. to 23° C., 2° C. to 13° C., 4° C. to 13° C., 4.5° C. to 13° C., 5° C. to 13° C., 6.5° C. to 13° C., 9° C. to 13° C., or 11° C. to 13° C. In the temperature glide range, compositional separation may not occur even when the mixed refrigerant composition is used in a heat pump. Accordingly, the heat transfer efficiency of the refrigerant may be improved.

[0067] In some embodiments, the latent heat at -25 °C can be from 150 kJ / kg to 250 kJ / kg, from 180 kJ / kg to 250 kJ / kg, from 180 kJ / kg to 230 kJ / kg, from 180 kJ / kg to 220 kJ / kg, from 190 kJ / kg to 220 kJ / kg, from 195 kJ / kg to 220 kJ / kg, from 200 kJ / kg to 215 kJ / kg, or from 205 kJ / kg to 215 kJ / kg.

[0068] Within the above latent heat range, the heat released or absorbed by the mixed refrigerant composition during phase change may be sufficient. Accordingly, the thermal efficiency of the mixed refrigerant composition may be improved.

[0069] In some embodiments, the global warming potential (GWP) of the mixed refrigerant composition may be from 1 to 40, from 1 to 30, from 5 to 30, from 10 to 30, from 10 to 28, from 15 to 28, or from 19 to 28.

[0070] Global warming potential (GWP) is a value calculated using carbon dioxide (CO2) as a reference substance for the effect on global warming over a certain period of time (e.g., 100 years) when 1 kg of any chemical substance is released into the Earth's troposphere.

[0071] Within the above global warming potential range, cooling capacity can be improved while suppressing environmental pollution caused by the use and handling of mixed refrigerant compositions.

[0072] In some embodiments, the ozone depletion potential (ODP) of the mixed refrigerant composition may be 0.

[0073] Ozone Depletion Potential (ODP) is a numerical value that converts the degree to which a chemical substance affects the destruction of the ozone layer, assuming that the ozone depletion effect of trichlorofluoromethane (CFC-11) is 1.

[0074] Since the above ozone depletion potential (ODP) is 0, environmental pollution caused by the use and processing of the mixed refrigerant composition can be suppressed.

[0075] In some embodiments, the mixed refrigerant composition may be non-flammable. For example, it may be rated A2L according to the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) refrigerant safety group classification. This may enhance the safety of the heat pump during operation and leakage.

[0076] According to exemplary embodiments, a heat pump comprises the above-described mixed refrigerant composition. Accordingly, the heat pump can exhibit improved refrigeration performance while enhancing environmental friendliness and stability.

[0077] The above heat pump may include a compressor, a condenser, an expansion valve, and an evaporator. In the compressor, the above-described mixed refrigerant composition may be compressed to a high temperature and high pressure state, and in the expansion valve, the above-described mixed refrigerant composition may be expanded to a low temperature and low pressure state.

[0078] For example, the above-described mixed refrigerant composition can release or absorb heat while circulating through a compressor, a condenser, an expansion valve, and an evaporator inside the heat pump. The mixed refrigerant composition can be maintained in a high-temperature and high-pressure gaseous state in the compressor. The mixed refrigerant composition can be liquefied into a liquid state by releasing heat in the condenser. The mixed refrigerant composition can be maintained in a low-temperature and low-pressure liquid, or a liquid and gaseous mixture, in the expansion valve. The mixed refrigerant composition can be vaporized into a gaseous state by absorbing heat in the evaporator.

[0079] In some embodiments, the heat pump may include oil. For example, the oil may include paraffin, naphthene, aromatic hydrocarbon, polyester (POE), polyol ester, mineral oil, alkylbenzene (AB), polyalkylene glycol (PAG), polyvinyl ether (PVE), and the like. Accordingly, friction and wear of the heat pump may be prevented.

[0080] In some embodiments, the coefficient of performance (COP) of the heat pump may be 1 to 10. The coefficient of performance (COP) refers to the ratio of the amount of heat effectively obtained to the amount of work input when operating the heat pump.

[0081] A high-efficiency heat pump having a performance coefficient within the above range can be provided using the above-described refrigerant.

[0082] Hereinafter, preferred embodiments are presented to help understand the present application, but these embodiments are only illustrative of the present application and do not limit the scope of the appended claims. It is obvious to those skilled in the art that various changes and modifications to the embodiments are possible within the scope and technical idea of ​​the present application, and it is also natural that such changes and modifications fall within the scope of the appended claims.

[0083]

[0084] Examples and Comparative Examples

[0085] (1) Mixed refrigerant composition

[0086] A mixed refrigerant composition having the components and contents (weight %) described in Table 1 below was prepared.

[0087] The boiling point, critical temperature, critical pressure, temperature gradient at 1.5 bar and 15 bar, and latent heat at -25°C of the prepared mixed refrigerant composition were measured. The boiling point, critical temperature, critical pressure, temperature gradient at 1.5 bar and 15 bar, and latent heat at -25°C of the measured mixed refrigerant composition are shown in Table 1 below.

[0088] The boiling point, critical temperature, critical pressure, temperature gradient, and latent heat of the above mixed refrigerant composition were measured using REFPROP (Ver 10, NIST).

[0089] Content of each component of the mixed refrigerant composition (weight %) Boiling point (℃) Critical temperature (℃) Critical pressure (bar) Temperature gradient - Latent heat at 25 ℃ (kJ / kg) R-744 R-1234yf R-152a 1.5 bar (℃) 15 bar (℃) Example 1 1945-35.5 8796.06 936.30 64.87 32.4 18186.00 Example 2 18910-35.33 896.60 336.87 34.66 62.35 9192.95 Example 3 18415-35.08 297.199 37.43 14.50 22.30 4 199.97 Example 417920-34.81997.86137.9864.3852.262207.10Example 52935-40.70196.56937.9769.2644.909187.30Example 628810-40.26697.01738.4788.8994.780194.25Example 728315-39.85197.52838.9718.6014.668201.31Example 827820-39.45498.12838.4768.3734.575208.45Example 93925-45.17296.91439.57113.1357.432188.57Example 1038710-44.60997.29840.01812.6577.228195.56Example 1138215-44.07997.75740.46312.2627.052202.64Example 1237720-43.58398.28540.90511.9536.910209.80Example 134915-49.05697.12141.09316.5039.933189.83Example 1448610-48.40697.45841.49315.9509.656196.84 Example 1548115-47.79797.87041.89315.4899.417203.95 Example 1647620-47.23098.37642.30815.1239.221211.14 Example 175905-52.42897.25742.58919.41112.373191.09 Example 1858510-51.72197.55442.94518.81012.024198.13 Example 1958015-51.05897.92443.29818.31011.724205.25 Example 2057520-50.44398.37643.66117.90911.481212.47Example 2156530-49.34399.51644.42417.38811.146227.17Comparative Example 101000-29.794.733.800177.9Comparative Example 255540-48.389100.945.20917.1811.003242.23Comparative Example 3106030-60.46298.61750.48726.81220.608233.93Comparative Example 4105040-59.36399.85751.01426.6120.293249.18Comparative example 5157510-69.59895.42855.7132.76728.813210.78Comparative example 6155530-66.97396.90255.97131.71727.193240.66.

[0090] The specific ingredients listed in Table 1 are as follows.

[0091] R-744: carbon dioxide

[0092] R-1234yf: 2,3,3,3-tetrafluoropropane

[0093] R-152a: 1,1-difluoroethane

[0094]

[0095] Experimental example

[0096] (1) GWP calculation

[0097] Based on the global warming potential (GWP) of R-744, R-1234yf, and R-152a included in the mixed refrigerant composition according to the examples, according to the Intergovernmental Panel on Climate Change (IPCC), the global warming potential (GWP) of the mixed refrigerant composition was calculated by taking the arithmetic average according to the weight ratio of each of R-744, R-1234yf, and R-152a.

[0098] The above global warming potential (GWP) according to the IPCC is based on the global warming potential (GWP) based on a 100-year period.

[0099] The calculated global warming potentials (GWPs) are shown in Table 2 below.

[0100] Classification Global Warming Potential (GWP) Example 17.15 Example 213.30 Example 319.45 Example 425.6 Example 57.15 Example 613.30 Example 719.45 Example 825.60 Example 97.15 Example 1013.30 Example 1119.45 Example 1225.60 Example 137.15 Example 1413.30 Example 1519.45 Example 1625.60 Example 177.15 Example 1813.30 Example 1919.45 Example 2025.60 Example 2137.90 Comparative Example 11Comparative Example 250.2 Comparative Example 337.9 Comparative Example 450.2 Comparative Example 513.3 Comparative Example 637.9

[0101] (2) Cooling evaluation

[0102] Figures 1 and 2 are schematic diagrams showing the flow of mixed refrigerant for heat exchange in cooling mode or heating mode of a heat exchanger according to exemplary embodiments, respectively.

[0103] The direction of the arrows in Figures 1 and 2 is intended to indicate the flow of the mixed refrigerant.

[0104] Referring to Figure 1, in cooling mode, the mixed refrigerant is compressed through the compressor, sequentially bypasses the internal condenser and expansion valve (heating), releases heat from the external condenser, expands in the expansion valve (cooling), and reabsorbs heat through the evaporator.

[0105] Referring to Figure 2, in heating mode, the mixed refrigerant is compressed through a compressor, releases heat from an internal condenser, expands in an expansion valve (heating), absorbs heat from an external condenser, and then absorbs additional heat through a cooler.

[0106] Cooling evaluations and heating evaluations were performed using the refrigerant combinations of Examples 1 to 21 and Comparative Examples 1 to 6 at different ambient temperatures through the above-described heat exchanger.

[0107] The above cooling evaluation was performed with the outside temperature set to 45°C, and the above heating evaluation was performed with the outside temperature set to -7°C and -20°C, respectively. The conditions for the cooling evaluation and heating evaluation according to the above-described examples and comparative examples are shown in Table 3 below.

[0108] Specifically, the outside temperature (℃), condenser outlet refrigerant temperature, condenser outlet refrigerant subcooling, evaporator outlet refrigerant temperature, and evaporator outlet refrigerant superheat are shown together in Table 3 below.

[0109] ClassificationOperating modeOutside air temperature (℃)Condenser outlet refrigerant temperature (℃)Condenser outlet refrigerant subcooling (℃)Evaporator outlet refrigerant temperature (℃)Evaporator outlet refrigerant superheating (℃)Example 1Cooling 455510108Example 1Heating - 74010-201Example 1Heating - 202010-291Example 2Cooling 455510108Example 2Heating - 74010-201Example 2Heating - 202010-291Example 3Cooling 455510108Example 3Heating - 74010-201Example 3Heating - 202010-291Example 4Cooling 455510108Example 3 4 Heating-74010-201 Example 4 Heating-202010-291 Example 5 Cooling455510108 Example 5 Heating-74010-201 Example 5 Heating-202010-291 Example 6 Cooling455510108 Example 6 Heating-74010-201 Example 6 Heating-202010-291 Example 7 Cooling455510108 Example 7 Heating-74010-201 Example 7 Heating-202010-291 Example 8 Cooling455510108 Example 8 Heating-74010-201 Example 8 Heating-202010-291 Example 9 Cooling 455510108 Example 9 Heating - 740 10-201 Example 9 Heating - 2020 10-291 Example 10 Cooling 455510108 Example 10 Heating - 740 10-201 Example 10 Heating - 2020 10-291 Example 11 Cooling 455510108 Example 11 Heating - 740 10-201 Example 11 Heating - 2020 10-291 Example 12 Cooling 455510108 Example 12 Heating - 740 10-201 Example 12 Heating - 2020 10-291 Example 13 Cooling 455510108 Example 13 Heating-74010-201 Example 13 Heating-202010-291 Example 14 Cooling455510108 Example 14 Heating-74010-201 Example 14 Heating-202010-291 Example 15 Cooling455510108 Example 15 Heating-74010-201 Example 15 Heating-202010-291 Example 16 Cooling455510108 Example 16 Heating-74010-201 Example 16 Heating-202010-291 Example 17 Cooling455510108 Example 17 Heating-74010-201 Example 17 Heating-202010-291 Example 18 Cooling 455510108 Example18 Heating-74010-201 Example 18 Heating-202010-291 Example 19 Cooling455510108 Example 19 Heating-74010-201 Example 19 Heating-202010-291 Example 20 Cooling455510108 Example 20 Heating-74010-201 Example 20 Heating-202010-291 Example 21 Cooling455510108 Example 21 Heating-74010-201 Example 21 Heating-202010-291 Comparative Example 1 Cooling455510108 Comparative Example 1 Heating-74010-201 Comparative Example 1 Heating-202010-291 Comparison Example 2 Cooling455510108 Comparison Example 2 Heating-74010-201 Comparison Example 2 Heating-202010-291 Comparison Example 3 Cooling455510108 Comparison Example 3 Heating-74010-201 Comparison Example 3 Heating-202010-291 Comparison Example 4 Cooling455510108 Comparison Example 4 Heating-74010-201 Comparison Example 4 Heating-202010-291 Comparison Example 5 Cooling455510108 Comparison Example 5 Heating-74010-201 Comparison Example 5 Heating-202010-291 Comparison Example 6 Cooling455510108 Comparison Example 6 Heating-74010-201 Comparative Example 6 Heating-202010-291

[0110] The cooling and heating analyses for the examples and comparative examples in Table 3 were verified using the 0D analysis program Cycle-D (provided by NIST). Specifically, the cooling and heating analyses evaluated volumetric capacity, compressor outlet temperature, and pressure.

[0111] The above volumetric capacity was calculated using Equation 1 below.

[0112] [Formula 1]

[0113]

[0114] The evaluation results are shown in Tables 4 to 6 below.

[0115] Cooling evaluation (outside temperature: 45 ℃) Division Volume capacity (kJ / ㎥) Compressor outlet pressure (kPaA) Compressor outlet temperature (℃) Example 1 2618.9 1597.17 1.2 Example 2 2651.2 1601.77 2.3 Example 3 2678.2 1603.87 3.4 Example 4 2699.9 1603.77 4.6 Example 5 2654.6 1722.77 4.2 Example 6 2686.5 1724.47 5.3 Example 7 2712.7 1723.97 6.4 Example 8 2733.5 1721.37 7.6 Example 9 2690.5 1851.07 7.1 Example 102721.81849.778.2 Example 112747.61846.379.3 Example 122767.21841.380.4 Example 132726.51981.279.9 Example 142757.21976.881.0 Example 152782.41970.682.1 Example 162801.31962.983.3 Example 172762.82112.782.6 Example 182793.12105.183.7 Example 192817.52096.184.9 Example 202835.42085.786.0 Example 212853.72062.088.4Comparative Example 12545.51464.767.0Comparative Example 22856.82035.091.0Comparative Example 33017.92652.2100.7Comparative Example 43001.32603.6103.6Comparative Example 53174.23368.8105.4Comparative Example 63190.13220.8110.9

[0116] Heating evaluation (outside temperature: -7 ℃) Division Volume capacity (kJ / ㎥) Compressor outlet pressure (kPaA) Compressor outlet temperature (℃) Example 1 1369.8 1128.45 6.5 Example 2 1385.6 1130.15 8.3 Example 3 1398.2 1130.26 0.1 Example 4 1407.3 1128.86 1.9 Example 5 1410.5 1234.86 0.3 Example 6 1425.6 1233.76 2.1 Example 7 1437.0 1231.16 3.8 Example 8 1445.3 1227.46 5.6 Example 9 1450.9 1343.36 3.9 Example 101465.31339.365.6 Embodiment 111476.31334.167.4 Embodiment 121483.21328.069.2 Embodiment 131491.41453.367.4 Embodiment 141505.11446.369.1 Embodiment 151514.81438.570.9 Embodiment 161521.01429.972.7 Embodiment 171532.01564.070.7 Embodiment 181544.61554.272.4 Embodiment 191553.11543.674.2 Embodiment 201558.81532.576.1 Embodiment 211558.21509.379.9Comparative Example 11309.41018.450.8Comparative Example 21548.31484.984.0Comparative Example 31734.11998.595.1Comparative Example 41709.21954.899.5Comparative Example 51944.12603.699.3Comparative Example 61909.72465.4107.8

[0117] Heating evaluation (outside temperature: -20 ℃) ​​Division Volume capacity (kJ / ㎥) Compressor outlet pressure (kPaA) Compressor outlet temperature (℃) Example 1 106 0.36 7 3.23 9.3 Example 2 106 7.9 6 7 2.74 0.9 Example 3 107 3.16 7 1.44 2.6 Example 4 107 5.66 6 9.24 4.3 Example 5 109 3.87 5 3.64 3.7 Example 6 110 0.77 5 0.64 5.3 Example 7 110 5.17 4 7.0 Example 8 110 6.87 4 2.94 8.7 Example 9 1127 08 35.34 7.9 Example 101133.1829.949.5 Example 111136.7824.151.1 Example 121137.3817.952.8 Example 131159.7918.051.8 Example 141165.1910.153.4 Example 151167.8902.055.0 Example 161167.5893.856.7 Example 171192.11000.955.5 Example 181196.8990.757.1 Example 191198.7980.358.7 Example 201197.6970.160.5 Example 211187.6950.064.2Comparative Example 11014.9591.732.9Comparative Example 21170.1930.568.1Comparative Example 31324.01309.380.6Comparative Example 41294.31274.585.0Comparative Example 51508.91761.185.6Comparative Example 61458.11647.394.0

[0118] Referring to Table 4, in the examples within the scope of the present disclosure, the volumetric capacity in the cooling evaluation (outside temperature of 45 ℃) was 2618.9 kJ / ㎥ or more, and the compressor outlet temperature was 88.4 ℃ or less.

[0119] Volumetric capacity is the amount of energy that a refrigerant can contain per unit volume. The larger the volumetric capacity, the more energy the same volume of refrigerant can move, so the refrigerant has good air conditioning performance.

[0120] Compared to the examples, Comparative Example 1, which used R-1234yf alone, had a reduced volumetric capacity.

[0121] Referring to Comparative Examples 3 and 4, when R-152a was included in an amount of 30 wt% or more of the total weight of the mixed refrigerant composition, the cooling volume capacity tended to converge, while the compressor outlet pressure and compressor outlet temperature tended to increase.

[0122] Referring to comparative examples, it was shown that as the content of R-744 increased, the compressor outlet pressure and compressor outlet temperature tended to increase.

[0123] Referring to Table 5, in the examples within the scope of the present disclosure, the volumetric capacity in the heating evaluation (outside temperature of -7 ℃) was 1369.8 kJ / ㎥ or more, and the compressor outlet temperature was 79.9 ℃ or less.

[0124] Compared to the examples, Comparative Example 1, which used R-1234yf alone, had a reduced volumetric capacity.

[0125] Referring to Comparative Examples 3 and 4, when R-152a was included in an amount of 30 wt% or more of the total weight of the mixed refrigerant composition, the heating volume capacity tended to converge, while the compressor outlet pressure and compressor outlet temperature tended to increase.

[0126] Referring to comparative examples, it was shown that as the content of R-744 increased, the compressor outlet pressure and compressor outlet temperature tended to increase.

[0127] Referring to Table 6, in the examples within the scope of the present disclosure, the volumetric capacity in the heating evaluation (outside temperature of -20 ℃) ​​was 1060.3 kJ / ㎥ or more, and the compressor outlet temperature was 64.2 ℃ or less.

[0128] Compared to the examples, Comparative Example 1, which used R-1234yf alone, had a reduced volumetric capacity.

[0129] Referring to Comparative Examples 3 and 4, when R-152a was included in an amount of 30 wt% or more of the total weight of the mixed refrigerant composition, the heating volume capacity tended to converge, while the compressor outlet pressure and compressor outlet temperature tended to increase.

[0130] Referring to comparative examples, it was shown that as the content of R-744 increased, the compressor outlet pressure and compressor outlet temperature tended to increase.

[0131] Referring to the results in Tables 4 to 6, it is preferable to use a blended refrigerant containing all of R-744, R-1234yf, and R-152a rather than using R-1234yf as the sole refrigerant. In addition, it is preferable to limit the maximum content of R-744 to 10 wt% of the total weight of the blended refrigerant composition.

[0132] Additionally, considering that the GWP increases as the content of R-152a increases, it is desirable to limit the maximum content of R-152a to 30 wt% of the total weight of the mixed refrigerant composition.

Claims

1. Contains carbon dioxide (R-744), 2,3,3,3-tetrafluoropropene (R-1234yf) and 1,1-difluoroethane (R-152a). The content of the above carbon dioxide (R-744) is 1 wt% to 10 wt% of the total weight of the mixed refrigerant composition, The content of the above 2,3,3,3-tetrafluoropropene (R-1234yf) is 65 wt% to 95 wt% of the total weight of the mixed refrigerant composition, The content of the above 1,1-difluoroethane (R-152a) is 1 wt% to 30 wt% of the total weight of the mixed refrigerant composition, A mixed refrigerant composition having a boiling point at 1 atm of -65°C to -30°C.

2. A mixed refrigerant composition comprising the carbon dioxide (R-744), the 2,3,3,3-tetrafluoropropene (R-1234yf), and the 1,1-difluoroethane (R-152a) according to claim 1.

3. A mixed refrigerant composition according to claim 1, wherein the content of 1,1-difluoroethane (R-152a) is 13 wt% to 25 wt% of the total weight of the mixed refrigerant composition.

4. A mixed refrigerant composition according to claim 1, wherein the content of 1,1-difluoroethane (R-152a) is 18 wt% to 23 wt% of the total weight of the mixed refrigerant composition.

5. A mixed refrigerant composition according to claim 1, wherein the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition is 6 to 95.

6. A mixed refrigerant composition according to claim 1, wherein the ratio of the content of 1,1-difluoroethane (R-152a) to the content of carbon dioxide (R-744) in the total weight of the mixed refrigerant composition is 0.5 to 30.

7. A mixed refrigerant composition according to claim 1, wherein the ratio of the content of 2,3,3,3-tetrafluoropropene (R-1234yf) to the content of 1,1-difluoroethane (R-152a) in the total weight of the mixed refrigerant composition is 2 to 19.

8. A mixed refrigerant composition according to claim 1, wherein the critical temperature of the mixed refrigerant composition is 90°C to 100°C.

9. A mixed refrigerant composition according to claim 1, wherein the critical pressure of the mixed refrigerant composition is 30 bar to 51 bar.

10. A mixed refrigerant composition according to claim 1, wherein the temperature glide of the mixed refrigerant composition at a pressure of 1.5 bar is 3°C to 29°C.

11. A mixed refrigerant composition according to claim 1, wherein the temperature glide of the mixed refrigerant composition at a pressure of 15 bar is 2°C to 23°C.

12. A mixed refrigerant composition according to claim 1, wherein the latent heat of the mixed refrigerant composition at -25°C is 150 kJ / kg to 250 kJ / kg.

13. A mixed refrigerant composition according to claim 1, wherein the mixed refrigerant composition has a global warming potential (GWP) of 1 to 40.

14. A heat pump comprising the mixed refrigerant composition of claim 1.

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