JP2014111724A - Hydrocarbon mixture refrigerant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrocarbon mixture refrigerant that contributes to reduction of substitute fluorocarbons having greenhouse effect, energy saving in refrigeration and air-conditioning equipment, and prevention of global warming.SOLUTION: A hydrocarbon mixture refrigerant has a propane content of 55-98 mol%, a mole ratio of a propylene content to a total content of propane and propylene of 0.8 or less, and contains at least one selected from methane, ethylene, ethane, propyne, cyclopropane, butene, and isobutene. The hydrocarbon mixture refrigerant has a saturated vapor pressure of 0.3-1 MPa at 7°C, a saturated vapor pressure of 0.6-2.2 MPa at 35°C, and a boiling point of -20°C or less, and satisfies a specific equation.

Description

  The present invention relates to a hydrocarbon mixed refrigerant that does not use chlorofluorocarbon or alternative chlorofluorocarbon, a refrigeration / refrigeration / cooling / air conditioning system using the same, a refrigeration / refrigeration / cooling / air conditioning method using the hydrocarbon mixed refrigerant, and a refrigeration / refrigeration / cooling / air conditioning system. It relates to a manufacturing method.

  Conventionally, so-called Freon (CFC, chlorofluorocarbon) such as dichlorodifluoromethane (CFC12) and chlorotrifluoromethane (CFC13) has been used as a refrigerant for air conditioners and refrigerators. However, chlorofluorocarbon has been abolished in Japan because it destroys the ozone layer and seriously affects the global environment. Therefore, HCFC (hydrochlorofluorocarbon) such as dichlorofluoromethane (HCFC21) and chlorodifluoromethane (HCFC22), 1,1,2,2-tetrafluoroethane (HFC134), 1,1,1,2-tetrafluoroethane Alternative chlorofluorocarbons represented by HFC (hydrofluorocarbon) such as (HFC-134a) and 1,1,1-trifluoroethane (HFC143a) have been developed. These HCFCs and HFCs have a low or zero ability to decompose the ozone layer compared to CFCs, but the action of warming the earth is several hundred to several thousand times that of carbon dioxide. It is very big.

Under such circumstances, natural refrigerants such as carbon dioxide, ammonia, and hydrocarbons have been used as refrigerants that replace HCFCs and HFCs. As the hydrocarbon refrigerant, for example, isobutane is used as a refrigerant for a domestic refrigerator in Japan.
Furthermore, it is known that propane or a refrigerant mixed with the same number of moles of propane and isobutane shows air conditioning performance equivalent to HFC of an air conditioner, but since the required refrigerant charging amount is greatly increased than a domestic refrigerator, Advanced refrigerant flammability countermeasures on the equipment side and a reduction in refrigerant charge amount are major issues for practical application.
In recent years, there is an urgent need for power saving measures for refrigeration air-conditioning equipment as a measure against global warming.

  In Patent Documents 1 and 2, as a hydrocarbon mixed refrigerant that can replace Freon R12, which was difficult to replace with a hydrocarbon simple substance refrigerant, a physical property that approximates Freon R12 in terms of evaporation and condensation temperature under pressure when a sufficient amount is filled. The use of a mixed refrigerant of propane and butane so as to have a specific characteristic, or the use of a mixed refrigerant of propane, butane and ethane so as to have a vapor pressure curve approximating that of Freon R12 is described. However, these mixed refrigerants have a problem that a sufficient refrigerating and air-conditioning function cannot be obtained to replace the above-mentioned substitute CFCs.

Patent Document 3 describes a refrigerant containing ethane, propane, isobutane, n-butane, isopentane, and n-pentane, but its purpose is a problem that the ignition point of the propane and butane refrigerant is as low as about 400 ° C. There is a problem that a sufficient refrigeration and air-conditioning function cannot be obtained to replace alternative chlorofluorocarbons such as HCFC and HFC.
US Pat. No. 6,336,333 International Application Publication No. 97/20902 JP 2004-35701 A

An object of the present invention is to replace a substitute chlorofluorocarbon (HCFC, HFC) having a lower boiling point and higher vapor pressure than chlorofluorocarbon (CFC) with a hydrocarbon refrigerant of a natural refrigerant, thereby enabling non-fluorocarbons using a hydrocarbon refrigerant of a natural refrigerant. It is to contribute to the prevention of global warming by reducing alternative chlorofluorocarbons, which are greenhouse gases, and saving energy in refrigeration air conditioners.
More specifically, a hydrocarbon mixed refrigerant that contributes to power saving of refrigeration air-conditioning equipment, and that can reduce the refrigerant charge amount and facilitate measures for flammability of equipment, and an air-conditioning system using the same. And providing an air conditioning method.

The hydrocarbon mixed refrigerant according to the first aspect of the present invention has a propane content of 55 to 98 mol%, a propylene content of 0.8 or less in terms of molar ratio to the total content of propane and propylene, and A hydrocarbon mixed refrigerant containing at least one selected from methane, ethylene, ethane, propyne, cyclopropane, butene and isobutene, having a saturated vapor pressure at 7 ° C of 0.3 to 1 MPa and a saturated vapor at 35 ° C The pressure is 0.6 to 2.2 MPa, the boiling point is −20 ° C. or less, and one or more of the formulas (V) to (IX) are satisfied.
COP _RC (7 ° C./35° C.) / {ΡL (7 ° C.) × (1 / ρV (7 ° C.))} ≧ 4.6... Formula (V)
[In the formula, COP _RC (7 ° C / 35 ° C): Theoretical cooling performance coefficient of a refrigeration cycle with an evaporation temperature of 7 ° C and a condensation temperature of 35 ° C ρL (7 ° C): 7 ° C, or if it is non-azeotropic 7 ° C. saturated vapor pressure and saturated liquid density at equal pressure (kg / l) ρV (7 ° C.): 7 ° C. saturated vapor density (mol-kg / m 3)]
COP _RH (7 ° C./35° C.) / {ΡL (35 ° C.) × (1 / ρV (35 ° C.))} ≧ 11.9... Formula (VI)
[In the formula, COP _RH (7 ° C./35° C.): Theoretical heating coefficient of performance of a refrigeration cycle having an evaporation temperature of 7 ° C. and a condensation temperature of 35 ° C. ρL (35 ° C.): 35 ° C. Saturated vapor pressure at 35 ° C. and saturated liquid density at equal pressure (kg / l) ρV (35 ° C.): saturated vapor density at 35 ° C. (mol-kg / m ³ )]
COP _RC (0 ° C./50° C.) / {ΡL (0 ° C.) × (1 / ρV (0 ° C.))} ≧ 1.7 Formula (VII)
[In the formula, COP _RC (0 ° C./50° C.): theoretical cooling coefficient of performance of a refrigeration cycle with an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C. ρL (0 ° C.): 0 ° C. Saturated vapor pressure at 0 ° C. and saturated liquid density at equal pressure (kg / l) ρV (0 ° C.): saturated vapor density at 0 ° C. (mol-kg / m ³ )]
COP _RH (0 ° C./50° C.) / {ΡL (50 ° C.) × (1 / ρV (50 ° C.))} ≧ 9.6 ··· formula (VIII)
[In the formula, COP _RH (0 ° C./50° C.): Theoretical heating coefficient of performance of a refrigeration cycle having an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C. ρL (50 ° C.): 50 ° C. 50 ° C. saturated vapor pressure and equal pressure saturated liquid density (kg / l) ρV (50 ° C.): 50 ° C. saturated vapor density (mol-kg / m ³ )]
COP _RC (−15 ° C./30° C.) / {ΡL (−15 ° C.) × (1 / ρV (−15 ° C.))} ≧ 1.2 (Equation (IX))
[In the formula, COP _RC (−15 ° C./30° C.): Theoretical cooling performance coefficient of a refrigeration cycle having an evaporation temperature of −15 ° C. and a condensation temperature of 30 ° C. ρL (−15 ° C.): −15 ° C., or non-azeotropic In the case of the nature, saturated vapor density of -15 ° C and saturated liquid pressure (kg / l) ρV (-15 ° C): saturated vapor density of -15 ° C (mol-kg / m ³ )]

Moreover, the hydrocarbon mixed refrigerant of a desirable aspect of the present invention is characterized in that the ethane content is 2 to 25 mol% in the hydrocarbon mixed refrigerant of the first aspect.

In addition, the hydrocarbon mixed refrigerant according to a desirable aspect of the present invention is characterized in that the methane content is 2 to 25 mol% in the hydrocarbon mixed refrigerant according to any one of the first and second aspects.

In addition, the hydrocarbon mixed refrigerant of a desirable aspect of the present invention is characterized in that the ethylene content in the hydrocarbon mixed refrigerant of any of the first and second aspects is 2 to 30 mol%.

Further, the hydrocarbon mixed refrigerant according to a preferred aspect of the present invention is the hydrocarbon mixed refrigerant according to any one of the first to fourth aspects, wherein the total content of n-butane and isobutane is 1 to 24 mol%, n -The butane content is 19 mol% or less, and the isobutane content is 12 mol% or less.

  According to the present invention, an alternative chlorofluorocarbon having a boiling point lower than that of chlorofluorocarbon and having a high vapor pressure can be replaced with a natural refrigerant, reducing the chlorofluorocarbon alternative chlorofluorocarbon, and energy saving of refrigeration and air conditioning equipment. Can contribute to the prevention of global warming.

  The hydrocarbon mixed refrigerant of the present invention can use the conventional refrigeration and air conditioning system (refrigeration and air conditioning equipment) in which an alternative chlorofluorocarbon refrigerant has been used as it is. For this reason, it is not necessary to install a new device, and by using the hydrocarbon mixed refrigerant of the present invention with respect to the previous device, the greenhouse gas can be reduced extremely quickly and energy can be saved. Can contribute to the prevention of global warming in various ways. Further, by using the hydrocarbon mixed refrigerant of the present invention, an energy-saving air conditioner can be manufactured in a short period of time by using the technology and design of a conventional refrigeration air conditioner of an alternative chlorofluorocarbon refrigerant.

Furthermore, if the hydrocarbon mixed refrigerant of the present invention is used, the refrigerant disposal cost can be greatly reduced as compared with that of a conventional alternative chlorofluorocarbon.
Furthermore, if the hydrocarbon mixed refrigerant of the present invention is used, higher refrigeration and air conditioning performance can be obtained than propane, which is conventionally known in refrigeration and air conditioning equipment using alternative chlorofluorocarbon refrigerant, or a hydrocarbon refrigerant in which propane and isobutane are mixed in the same number of moles. Therefore, it is possible to reduce the refrigerant charge amount and facilitate the measures against the refrigerant flammability of the equipment.

It is a figure which shows the sample container used for the saturation vapor pressure measurement of a refrigerant | coolant. It is a sample container used for measuring the critical point and saturation vapor pressure of a refrigerant. It is a figure which shows the saturated vapor pressure measuring apparatus of a refrigerant | coolant. It is a graph which shows the result of the freezing / refrigeration test of R22 and refrigerant B. It is a graph which shows the result of the freezing and refrigeration test of R134a and refrigerant B. It is a graph which shows the result of the freezing and refrigeration test of R134a and refrigerant A. It is a graph showing the relationship between the measured COP and the refrigerant theoretical COP _R in cooling of the inverter heat pump air conditioner. Is a graph showing the relationship between the measured COP and the refrigerant theoretical COP _R in the heating of the inverter heat pump air conditioner. It is a graph which shows the relationship with theoretical COP (7 degreeC / 35 degreeC) of the binary mixed refrigerant | coolant of a propane and C2, C3 hydrocarbon. It is a graph which shows the relationship with theoretical COP (7 degreeC / 35 degreeC) of the binary mixed refrigerant | coolant of a propane and C1, C5 hydrocarbon. It is a graph which shows the relationship with theoretical COP (7 degreeC / 35 degreeC) of the binary mixed refrigerant | coolant of a propane and C4 hydrocarbon.

DESCRIPTION OF SYMBOLS 1,10 Sample container 2 Pressure sensor 3 Sheath type platinum resistance thermometer 4 High pressure valve 5 Digital multimeter 6 Computer 7 Thermostatic chamber 8 DC power source 11 Transparent part 12 Sapphire glass 13 O-ring 14 Backup ring 15 Sample container main body 16 Central member

  The hydrocarbon mixed refrigerant of the embodiment (1) contains propane, may further contain n-butane and isobutane, and may further contain ethane. These hydrocarbon mixed refrigerants have a saturated vapor pressure at 7 ° C. of 0.3 to 1 MPa, preferably 0.35 to 0.9 MPa, and a saturated vapor pressure at 35 ° C. of 0.6 to 2.2 MPa, preferably 0.8. It mixes so that it may become the conditions of -2.2MPa, More preferably, 1.3-1.5MPa. If the saturated vapor pressure at 7 ° C. of the hydrocarbon mixed refrigerant is less than 0.3 MPa, sufficient refrigerating and air conditioning performance cannot be obtained, and if it exceeds 1 MPa, sufficient energy saving effect cannot be obtained. Further, when the saturated vapor pressure at 35 ° C. of the hydrocarbon mixed refrigerant is less than 0.6 MPa, sufficient refrigerating and air conditioning performance cannot be obtained, and when the value exceeds 2.2 MPa, sufficient energy saving effect cannot be obtained.

  The blending ratio of propane with respect to the total hydrocarbon mixed refrigerant is 50 to 97 mol%, more preferably 60 to 93 mol%. By setting it as this range, the saturated vapor pressure of the refrigerant at 7 ° C. and 35 ° C. can be adjusted to a preferable value. Propylene can be used in combination with propane in a molar ratio of (propylene) / (propane + propylene) = 0 to 0.8.

  The blending ratio of n-butane and isobutane is 39 mol% or less in total, preferably 0.2 to 39 mol%, more preferably 1.0 to 24 mol%. By setting this range, various alternative CFCs can be replaced. The compounding ratio of n-butane is 19 mol% or less, preferably 0.1 to 19 mol%, and the compounding ratio of isobutane is 12 mol% or less, preferably 0.1 to 12 mol%. By setting it as this range, the saturated vapor pressure of the refrigerant at 7 ° C. and 35 ° C. can be finely adjusted to a preferable value.

  The blending ratio of ethane is preferably 3 mol% or more. By setting it as such a mixture ratio, the saturated vapor pressure of 7 degreeC and 35 degreeC can be adjusted to the higher one. It is also possible to use methane or ethylene or both in place of ethane or in combination with ethane. In this case, methane can be used at a molar ratio of (methane) / (ethane + methane) = 0 to 0.8, and ethylene has a molar ratio of (ethylene) / (ethane + ethylene) = 0. It can be used in the range of ~ 0.8.

    The boiling point of the hydrocarbon mixed refrigerant of embodiment (1) is preferably −20 ° C. or lower. This is because the pressure of the hydrocarbon mixed refrigerant is increased to increase the refrigerant capacity, thereby making it possible to replace HCFCs and HFCs with high refrigeration capacity. In the present invention, the term “refrigerant” is used not only for a medium used for cooling but also for heating. This is because if the refrigerant is compressed, heat is generated and the heat can be used for heating.

Furthermore, it is extremely burdensome for the tester to find out the optimum condition of the refrigerant component by conducting many trial manufactures of various refrigerants, actual measurement of thermodynamic properties, and actual freezing / refrigeration tests and cooling / heating tests many times. However, as a result of focusing on the coefficient of performance of the refrigerant's theoretical refrigeration cycle (refrigerant theory COP _R ) and related thermodynamic properties, the present inventors have conducted a cooling / heating test directly related to the power consumption of the air-conditioning refrigeration equipment. It has been found that the measured COP according to the above has a certain relationship with the refrigerant theory COP _R. FIG. 7 is a graph for cooling showing the relationship between the measured COP and the refrigerant theory COP _R of the inverter heat pump air conditioner, and FIG. 8 is a graph for heating. That is, when the measured COP is taken on the vertical axis and (refrigerant theory COP _R ) / {saturated liquid density ρL kg / l × (1 / saturated vapor density ρV mol-kg / m ³ )} is taken on the horizontal axis, FIG. As shown in FIG. 8, it has been found that there is a substantially proportional relationship. Measured COP was made by Nippon Pemac Co., Ltd., using air heat source heat pump unit AEP22B. Three types of refrigerants with different refrigerant theory COPs, standard alternative CFC refrigerant R410A, filling amount 650 g, hydrocarbons prototyped in the study of the present invention Each of the mixed refrigerants A and B was charged with 260 g, and the frequency was changed for measurement. Here, the refrigerant theory COP _R is obtained from the relationship between the evaporating temperature and condensing temperature of the refrigeration cycle, the refrigerant pressure and the enthalpy by the method described in "Refrigeration and Air Conditioning Technology Elementary Text" (published by the Japan Refrigeration Association, 1991). Calculated from each enthalpy difference defined as refrigeration capacity and theoretical required compression power. However, if the hydrocarbon refrigerant of the present invention is non-azeotropic, the isotherm will deviate from the isobaric line even in the gas-liquid coexistence state, so set the evaporation temperature and condensation temperature with the saturated vapor line and change the isobaric pressure. The liquid side enthalpy was calculated. Various state equations and empirical equations have been proposed to calculate the thermodynamic properties such as the enthalpy of the refrigerant in the refrigeration cycle necessary to calculate this enthalpy, but the initial method differs from the measured value. However, there are few actual results of mixed hydrocarbon refrigerants, and the reliability has not been fully confirmed. Therefore, the inventors examined the NIST by comparing SUPERTRAPP (a thermodynamic property calculation program based on the Peng-Robinson equation of state) of The National Institute of Standards and Technology (NIST) and the actual value of the refrigerant. REFPROP 8.0 (latest thermodynamic property calculation program based on modified Benedict-Webb-Rubin equation of state and mixing rule) was selected and enthalpy, saturated liquid density, saturated vapor density, etc. were calculated. It was found that _R has the above relationship.

In addition, the refrigerant theory COP _R and (refrigerant theory COP _R ) / {saturated liquid density × (1 / saturated vapor density)} obtained from the relationship with the measured COP are large, and can be replaced with chlorofluorocarbon alternatives. The components of the hydrocarbon mixed refrigerant having high performance were found from the thermodynamic property value simulation by REFPROP8.0 of the combination of propane and 23 kinds of hydrocarbons and the findings from the above experiments. The results are shown in the calculation examples shown in Tables 2 and 3 in the Examples section, and FIGS.

Based on this new knowledge, the refrigerant provided by the present invention has a coefficient of performance [refrigerant theory COP _R (7 ° C./35° C.)] of the theoretical refrigeration cycle having an evaporation temperature of 7 ° C. and a condensation temperature of 35 ° C. of 8.4. As described above, it is preferably 8.5 or more from the viewpoint of obtaining air conditioning and air conditioning performance from an alternative chlorofluorocarbon refrigerant or a conventional hydrocarbon refrigerant in an air conditioner such as a room air conditioner.

In addition, the coefficient of performance of the theoretical refrigeration cycle with an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C. [refrigerant theory COP _R (0 ° C./50° C.)] is 3.9 or more, preferably 4.0 or more. It is preferable from the viewpoint of obtaining air conditioning and air conditioning and refrigeration performance from alternative chlorofluorocarbon refrigerants and conventional hydrocarbon refrigerants in air conditioning and refrigeration equipment such as air conditioners, vending machines and refrigerators. Further, the coefficient of performance of the theoretical refrigeration cycle having an evaporation temperature of −15 ° C. and a condensation temperature of 30 ° C. [refrigerant theory COP _R (−15 ° C./30° C.)] is 4.5 or more, preferably 4.9 or more. Is preferable from the viewpoint of obtaining refrigeration / refrigeration performance from alternative CFC refrigerants and conventional hydrocarbon refrigerants in air-conditioning and refrigeration equipment such as refrigerators, commercial refrigerators, and commercial freezers.

Further, based on these findings, the refrigerant of the present invention is one of the formulas (V), (VI), (VII), (VIII), and (IX) at the evaporation temperature and the condensation temperature. From the viewpoint of obtaining refrigeration and air-conditioning performance from alternative chlorofluorocarbon refrigerants and conventional hydrocarbon refrigerants in the above equipment that is designed for relatively high pressure refrigerants such as R410A, preferably satisfying most, most preferably all of the above More preferred.
COP _RC (7 ° C./35° C.) / {ΡL (7 ° C.) × (1 / ρV (7 ° C.))} ≧ 4.6
.... Formula (V)
[In the formula, COP _RC (7 ° C./35° C.): Theoretical cooling performance coefficient ρL (7 ° C.) of a refrigeration cycle having an evaporation temperature of 7 ° C. and a condensation temperature of 35 ° C .: 7 ° C. Saturated vapor pressure of 7 ° C and saturated liquid density at equal pressure (kg / l)
ρV (7 ° C.): saturated vapor density at 7 ° C. (mol-kg / m ³ )]

COP _RH (7 ° C./35° C.) / {ΡL (35 ° C.) × (1 / ρV (35 ° C.))} ≧ 11.9
.... Formula (VI)
[In the formula, COP _RH (7 ° C./35° C.): Theoretical heating performance coefficient ρL (35 ° C.) of a refrigeration cycle having an evaporation temperature of 7 ° C. and a condensation temperature of 35 ° C .: 35 ° C. Saturated liquid pressure of 35 ° C and saturated pressure (kg / l)
ρV (35 ° C.): saturated vapor density at 35 ° C. (mol-kg / m ³ )]

COP _RC (0 ° C./50° C.) / {ΡL (0 ° C.) × (1 / ρV (0 ° C.))} ≧ 1.7
... Formula (VII)
[In the formula, COP _RC (0 ° C./50° C.): Theoretical cooling performance coefficient ρL (0 ° C.) of a refrigeration cycle having an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C .: 0 ° C. Saturated liquid pressure of 0 ° C and saturated pressure (kg / l)
ρV (0 ° C.): saturated vapor density at 0 ° C. (mol-kg / m ³ )]

COP _RH (0 ° C./50° C.) / {ΡL (50 ° C.) × (1 / ρV (50 ° C.))} ≧ 9.6
.... Formula (VIII)
[In the formula, COP _RH (0 ° C./50° C.): Theoretical heating performance coefficient ρL (50 ° C.) of a refrigeration cycle having an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C .: 50 ° C. Saturated liquid pressure of 50 ° C and saturated pressure (kg / l)
ρV (50 ° C.): saturated vapor density at 50 ° C. (mol-kg / m ³ )]

COP _RC (−15 ° C./30° C.) / {ΡL (−15 ° C.) × (1 / ρV (−15 ° C.))} ≧ 1.2
.... Formula (IX)
[Where COP _RC (−15 ° C./30° C.): theoretical cooling performance coefficient ρL (−15 ° C.) of a refrigeration cycle having an evaporation temperature of −15 ° C. and a condensation temperature of 30 ° C .: −15 ° C. or non-azeotropic In the case of sexuality, saturated vapor density of -15 ° C and saturated liquid density (kg / l)
ρV (−15 ° C.): saturated vapor density at −15 ° C. (mol-kg / m ³ )]

The refrigerant component of the present invention is mainly composed of propane having a thermodynamic property close to a relatively high-pressure alternative chlorofluorocarbon such as R410A in order to satisfy the above-mentioned thermodynamic properties, and is a C1 hydrocarbon, C2 hydrocarbon, C3 hydrocarbon, It contains at least one hydrocarbon selected from C4 hydrocarbons and has a high refrigerant theory COP and (COP _R ) / {saturated liquid density ρL × (1 / saturated vapor density ρV)}.
Since it has a higher refrigerant theory COP than conventional alternative chlorofluorocarbons and hydrocarbon refrigerants in which propane, propane and isobutane are mixed in the same number of moles, high performance can be obtained in various refrigeration and air-conditioning equipment. In addition, since (COP _R ) / {saturated liquid density ρL × (1 / saturated vapor density ρV)} is high, power consumption can be reduced in devices designed for relatively high-pressure refrigerant such as R410A. .
Normal pentane, isopentane, and neopentane of C5 hydrocarbons have the effect of improving COP when 30 mol% or more is mixed with propane, but the saturated vapor pressure and saturated vapor density are decreased, and the saturated liquid density is increased. Therefore, (COP _R ) / {saturated liquid density ρL × (1 / saturated vapor density ρV)} is lowered and it is difficult to adapt to equipment designed for high-pressure refrigerant. The same applies to C6 or higher hydrocarbons such as hexane and heptane.

  In the hydrocarbon mixed refrigerant of the present invention, propane is 55 to 98 mol% (in the hydrocarbon mixed refrigerant), preferably 60 to 96 mol%, more preferably 70 to 95 mol%, and methane, ethylene, ethane, n -It can contain at least one selected from butane, isobutane, propyne, cyclopropane, butene and isobutene.

  In the case of a binary mixed refrigerant composed of propane and one kind of hydrocarbon, as shown in the refrigerant theory COP of FIGS. 9 to 11, a refrigerant that can obtain higher refrigeration and air-conditioning performance than a conventional alternative chlorofluorocarbon refrigerant or a conventional hydrocarbon refrigerant. The component mol% varies depending on the type of hydrocarbon to be mixed. Fig. 9 shows the relationship between propane and C2, C3 hydrocarbons, Fig. 10 shows propane and C1, C5 hydrocarbons, and Fig. 11 shows the theoretical COP (7 ° C / 35 ° C) of binary mixed refrigerants of propane and C4 hydrocarbons. It is a graph which shows. When C1 and C2 hydrocarbons having fewer carbon atoms than propane are mixed, the refrigerant theoretical COP shows a maximum value in the range of 5 to 35 mol% and improves. Therefore, in the case of a mixed refrigerant of propane and methane, methane is 5 to 40. In view of the mol%, saturated vapor pressure, and the difference between the isotherm and the isobaric line in the coexisting state of gas and liquid, it is more preferably 5 to 25 mol% from the viewpoint of obtaining refrigeration and air-conditioning performance from alternative CFC refrigerants and conventional hydrocarbon refrigerants . In the case of a mixed refrigerant of propane and ethylene, it is more preferable from the same viewpoint that ethylene is 5 to 35 mol%. In the case of a mixed refrigerant of propane and ethane, it is more preferable that ethane is 5 to 25 mol% from the same viewpoint, and considering that the effect of improving the refrigerant theory COP is relatively small, 10 to 15 mol% which is close to the maximum value. Is more preferable.

  In the same C3 hydrocarbon as propane, propyne and cyclopropane have the effect of improving the refrigerant theory COP but tend to be flat. In the case of a mixed refrigerant of propane and propyne, propyne is 5 to 30 mol%. Is more preferable from the same viewpoint. In the case of a mixed refrigerant of propane and cyclopropane, cyclopropane is more preferably from 5 to 40 mol% from the same viewpoint. Further, mixing with C3 hydrocarbon has an advantage that the deviation between the isotherm and the isobar in the gas-liquid coexistence state is reduced.

  C4 or higher hydrocarbons, except for n-butane and isobutane, do not improve the refrigerant theory COP unless mixed at 30 mol% or higher. Therefore, the performance of the above equipment designed for relatively high pressure refrigerants such as R410A is considered. Then, the vapor pressure decreases, so it is difficult to use in a binary system. In the case of a mixed refrigerant of propane and n-butane, n-butane is preferably 15 mol% or more because the refrigerant theoretical COP can be improved. However, considering a decrease in vapor pressure, it is more preferably 25 mol% or less from the same viewpoint. preferable. In the case of a mixed refrigerant of propane and isobutane, it is preferable because isobutane is 5 mol% or more because the theoretical COP of the refrigerant can be improved, but considering a decrease in vapor pressure, it is more preferably 30 mol% or less from the same viewpoint. In the case of a mixed refrigerant of propane and isobutene, it is more preferable from the same viewpoint that isobutene is 25 to 35 mol%. In the case of a mixed refrigerant of propane and butene, it is more preferable from the same viewpoint that butene is 25 to 35%.

  A more preferable aspect of the hydrocarbon mixed refrigerant of the present invention is a propane ternary hydrocarbon mixed refrigerant in which C1 or C2 hydrocarbon and C4 hydrocarbon are combined and mixed, and the refrigerant is more refrigerant than the binary hydrocarbon mixed refrigerant. The theoretical COP can be improved. One specific embodiment contains 70 to 85 mol% propane, 10 to 25 mol% ethane, and 5 to 10 mol% isobutane. Moreover, another aspect contains 60-85 mol% of propane, 10-30 mol% of ethylene, and 5-15 mol% of isobutane. Yet another embodiment contains 50-90 mol% propane, 5-25 mol% methane, 5-20 mol% isobutane.

Further, an even more preferable aspect of the hydrocarbon mixed refrigerant of the present invention is a propane multi-component hydrocarbon mixed refrigerant in which at least one selected from ethane, ethylene, and methane is mixed with propane, isobutane, and n-butane. Further, (COP _R ) / {saturated liquid density ρL × (1 / saturated vapor density ρV)} can be easily improved from the ternary hydrocarbon mixed refrigerant.
Propane multi-component hydrocarbon mixed refrigerant contains propane 55 to 96 mol%, n-butane 0.2 to 28 mol%, isobutane 0.8 to 12 mol%, and ethane 2 to 11 mol%.
Further, ethane may contain up to 25 mol%, ethylene can contain 2 to 30 mol%, and methane can contain 2 to 25 mol%. Further, the content of other hydrocarbons is desirably 0.1 mol% or less.

  The refrigeration / refrigeration or air conditioning air conditioning method of the embodiment (1) uses an alternative chlorofluorocarbon refrigerant such as HCFC or HFC, or has used such an alternative chlorofluorocarbon refrigerant, or has used such an alternative chlorofluorocarbon. Applies to refrigeration or air-conditioning systems without In these refrigeration / refrigeration or air conditioning systems, the refrigerant flow path is filled with the above-described hydrocarbon mixed refrigerant so as to satisfy the expressions (I) and (II). More specifically, there are the following three modes.

  In the freezing / refrigeration or cooling / heating system using the alternative chlorofluorocarbon refrigerant, the alternative chlorofluorocarbon refrigerant is removed and replaced with the alternative chlorofluorocarbon refrigerant, and the hydrocarbon mixed refrigerant satisfying the formulas (I) and (II) is charged and operated. Alternatively, a refrigerant mixed refrigerant satisfying the formulas (I) and (II) is charged and operated in a refrigeration / refrigeration / cooling / heating system using the alternative fluorocarbon refrigerant from which the alternative fluorocarbon refrigerant has already been removed. Or, a refrigerant mixed refrigerant satisfying the formulas (I) and (II) is filled in and operated in a refrigeration / refrigeration or heating / air conditioning system that does not use an alternative chlorofluorocarbon refrigerant or has never used an alternative chlorofluorocarbon refrigerant. To do.

Formulas (I) and (II) of the embodiment (1) are as follows. That is,
(AB) ≦ 0.5 MPa Formula (I)
[In formula, A: Saturated vapor pressure of alternative CFC refrigerant at 7 ° C. B: Saturated vapor pressure of hydrocarbon mixed refrigerant at 7 ° C.]
(C−D) ≦ 1 MPa Formula (II)
[In the formula, C: saturated vapor pressure of alternative CFC refrigerant at 35 ° C. D: saturated vapor pressure of hydrocarbon mixed refrigerant at 35 ° C.]

  When the hydrocarbon mixed refrigerant satisfies the formulas (I) and (II), sufficient refrigeration / refrigeration / cooling / heating air conditioning capability and energy saving effect can be achieved at the same time even when many HCFCs and HFCs are replaced.

  In the embodiment (1), it is preferable that the hydrocarbon mixed refrigerant satisfies the formula (III). When the filling amount satisfies the formula (III), sufficient refrigeration / refrigeration or air conditioning capability and energy saving effect can be achieved simultaneously when replacing HCFC and HFC.

The above formula (III) is as follows. That is,
Q × (R / 3S) ≦ P ≦ Q × (R / S) (formula (III))
[In formula, P: Mass of filling of hydrocarbon mixed refrigerant Q: In an air-conditioning system in which an alternative chlorofluorocarbon refrigerant is used or has been used, it means a filling mass of the alternative chlorofluorocarbon refrigerant. In an air conditioning system in which an alternative chlorofluorocarbon refrigerant has never been used, it means the optimum mass of the alternative chlorofluorocarbon refrigerant to be used if it is assumed that the alternative chlorofluorocarbon refrigerant is used in the air conditioning system.
R: Critical density of hydrocarbon refrigerant S: Critical density of alternative chlorofluorocarbon refrigerant]

  As the value of Q, in an air conditioning system in which an alternative chlorofluorocarbon refrigerant has not been used, it means an optimum mass of the alternative chlorofluorocarbon refrigerant to be used assuming that the alternative chlorofluorocarbon refrigerant is used in the air conditioning system. . Here, the optimum mass of the alternative chlorofluorocarbon refrigerant changes the variables assumed by those skilled in the art such as the filling amount of the alternative chlorofluorocarbon, the frequency of the inverter of the air conditioner, and / or the degree of opening and closing of the expansion valve in the air conditioning system, This is the filling amount of alternative CFCs at which the measured COP (see (Note 2) in Table 1) is the maximum when the cooling test is performed according to the method of JIS B8615-1.

  In the embodiment (1), when determining the upper limit value and the lower limit value of the preferable charging mass of the refrigerant, if the critical density R of the hydrocarbon mixed refrigerant and the critical density S of the alternative chlorofluorocarbon refrigerant are actually known, those values are used. However, a method of determining an appropriate filling mass by changing the filling amount without knowing the critical density R of the hydrocarbon mixed refrigerant and the critical density S of the alternative chlorofluorocarbon refrigerant may be used. That is, the significance of the upper limit value and the lower limit value of the formula (III) means a numerical value that the filling mass P of the embodiment (1) is preferably between the upper limit value and the lower limit value of the formula (III) as a result. That's what it means. Therefore, it is irrelevant whether or not it is calculated by using the actual values of the critical density R of the hydrocarbon mixed refrigerant and the critical density S of the alternative chlorofluorocarbon refrigerant, and the left side Q × (R / 3S) and the right side Q The value of x (R / S) means only a numerical value regardless of the calculation method.

  The manufacturing method of the freezing refrigeration or the air conditioning air conditioning system of embodiment (1) is performed by filling the inside of a refrigerant flow path with a hydrocarbon mixed refrigerant so as to satisfy the above-mentioned formulas (I) and (II). . That is, the alternative chlorofluorocarbon refrigerant in the refrigeration / refrigeration or air conditioning system using the alternative chlorofluorocarbon refrigerant is removed, replaced with the alternative chlorofluorocarbon refrigerant, and filled with the hydrocarbon mixed refrigerant satisfying the formulas (I) and (II). . Alternatively, a refrigerant mixed refrigerant satisfying the formulas (I) and (II) is filled into a refrigeration / refrigeration / cooling / air-conditioning system using the alternative CFC-based refrigerant from which the CFC-based refrigerant has already been removed. Alternatively, a hydrocarbon mixed refrigerant satisfying the formulas (I) and (II) is filled in a refrigeration / refrigeration system that does not use an alternative chlorofluorocarbon refrigerant or has never used an alternative chlorofluorocarbon refrigerant.

  The embodiment (2) is applied in addition to the filling conditions of the formula (I) and the formula (II) in place of the formula (III) in the freezing / refrigeration or air conditioning air conditioning method of the embodiment (1). be able to. By adopting the filling condition of the formula (IV), a more advantageous air conditioning effect and energy saving can be achieved at the same time.

That is, in order to achieve sufficient freezing / refrigeration or air-conditioning / air-conditioning capability, it is preferable to use the following formula (IV) instead of the formula (III).
Q × (R / 2S) ≦ P ≦ Q × (R / S) (formula (IV))
[Wherein, P, Q, R, S: the above-mentioned meanings are shown]
The formula (IV) or (III) may be applied to the filling of the hydrocarbon mixed refrigerant independently of the formulas (I) and (II).
In the actual calculation, the critical densities of R and S in the formulas (III) and (IV) are calculated according to the same unit (for example, kg / l).

  The refrigerated refrigeration or air conditioning air conditioning system of the above-described embodiment uses the hydrocarbon mixed refrigerant described above. As described above, by using the hydrocarbon mixed refrigerant of the present invention, the conventional air conditioner using the alternative chlorofluorocarbon is used as it is or by slightly adjusting the frequency of the air conditioner inverter or the opening / closing degree of the expansion valve. can do. However, the present invention is not limited to this, and a freezing / refrigeration or cooling / heating air conditioning system dedicated to the hydrocarbon mixed refrigerant of the embodiment may be constructed.

  Hereinafter, the embodiment will be described more specifically by way of examples.

[Example 1] <Preparation of refrigerants A and B>
Refrigerants A and B having the compositions shown in Table 1 were prepared by mixing propane, n-butane, isobutane, and ethane.

  In this embodiment, the saturated vapor pressure is measured by filling a sample container having a known internal volume with a sample (refrigerant) and measuring the temperature and pressure while keeping the sample container under a predetermined temperature condition. FIG. 1 shows a sample container, (a) is a plan view, (b) is a front view, and (c) is a left side view. FIG. 2 shows another sample container, (A) is a side view, and (B) is a cross-sectional view in the aa direction. FIG. 3 shows a saturated vapor pressure measuring apparatus that performs measurement using the sample container of FIG.

The sample container 1 is, for example, a SUS304 container having an internal volume of about 70 cm ³ as shown in FIG. A structure in which the density distribution in the height direction due to the weight of the sample is kept as small as possible, and a thick cylinder whose shape and external force are axisymmetric so as to achieve uniform deformation and pressure due to internal pressure, and these are crossed It has become.
Further, as the sample container 10, for example, a container made of SUS304 having an internal volume of about 600 cm ³ can be used as shown in FIG. There is a transparent portion at the center of the sample container 10 where the presence of a liquid meniscus (gas-liquid interface) can be confirmed. The sample container 10 is mainly used for measuring the critical point of the sample. In the figure, 12 is a sapphire glass, 13 is an O-ring, and 14 is a backup ring. The sample container body 15 is sandwiched and fixed by a central member 16.

  In the saturated vapor pressure measuring apparatus of FIG. 3, reference numeral 1 denotes the sample container shown in FIG. 1, and a pressure sensor 2, a sheath type platinum resistance temperature detector 3 and a high pressure valve 4 are attached to the tip of the sample container 1, respectively. Yes. The sample temperature is measured using a sheath type platinum resistance temperature detector 3 inserted in the sample container 1, and the sample pressure is measured using a pressure sensor 2 directly connected to the sample container 1. The temperature and pressure of the sample in the sample container 1 are each measured by the digital multimeter 5 as an electrical signal, and converted into respective physical quantities by the computer 6 and recorded.

In the measurement, first, the inside of the sample container 1 is evacuated to 3 × 10 ⁻³ Pa or less with an air-cooled turbo molecular pump, and then the sample is filled. The filling amount of the sample is determined in consideration of (internal volume) × (saturation density). Thereafter, the sample container 1 is installed in the thermostat 7 every 5 minutes, and the saturated vapor pressure of the sample is measured. The pressure when the temperature and pressure do not fluctuate and become a constant value is the saturated vapor pressure. This operation is performed by setting a thermostat at 7 ° C. and 35 ° C.

[Test Example 1] <Cooling performance test>
The cooling performance test was performed according to the method described in JIS B8615-1. As an air conditioner, a test was performed using an air heat source heat pump unit AEP22B (trademark) manufactured by Nippon Pemac Co., Ltd.
Air conditioner AEP22B was installed in the test chamber. Since the air conditioner AEP22B uses R410A, which is an HFC-based refrigerant, as a refrigerant, the measurement of R410A is performed as it is and is set as Comparative Example 1. For refrigerants A and B, after removing R410A from the air conditioner, the respective refrigerants are filled and operated, and the charge amount is changed in two cases two by refrigerant A in Examples 2 and 3 and refrigerant B in Example 4. It was set to 5. For each refrigerant, the refrigerant filling amount, the inverter frequency, and the air volume were changed, and the conditions under which the measured COP value (see (Note 2) in Table 1) was the optimum value were determined.

The cooling operation was performed under the conditions shown in Table 1, and the measured COP was calculated. In this case, the indoor suction dry bulb temperature is 26.98 to 27.00 ° C., the indoor suction wet bulb temperature is 18.96 to 18.99 ° C., and the outdoor suction dry bulb temperature is 34.95 to 35.07. The outdoor suction wet bulb temperature was maintained at 22.07-24.03 ° C. When the measured COP value was the optimum value, the air volume of the refrigerant A was 7.64 m ³ / min, and the air volume of the refrigerant B was 7.31 m ³ / min.

As shown in Table 1, when the refrigerants A and B were used (Examples 2 to 5), it was possible to achieve an actually measured COP that was superior to when R410A (Comparative Example 1) was used. Moreover, when the refrigerant | coolant B and the refrigerant | coolant A were compared, the refrigerant | coolant B showed the cooling capacity and the cooling actual measurement COP which were more excellent.
Further, the _{COP RC} (7/35 ℃) calculated by the _{method, COP RC (7/35 ℃} ) / {ρL (7 ℃) × (1 / ρV (7 ℃)}, COP RC (0/50 ℃ ), COP _RC (0/50 ° C.) / {ΡL (0 ° C.) × (1 / ρV (0 ° C.)}, COP _RC (−15 / 30 ° C.), and COP _RC (−15 / 30 ° C.) / { ρL (−15 ° C.) × (1 / ρV (−15 ° C.)} is shown in Table 1.

[Test Example 2] <Heating capacity test>
The heating capacity test conformed to the method described in JIS B8615-1. With the same air conditioner used in Test Example 1, the refrigerant A (Examples 6 and 7), the refrigerant B (Examples 8 and 9), and the R410A (Comparative Example 2) were changed for each refrigerant. ), The refrigerant filling amount, the inverter frequency, and the air volume were changed, and the conditions under which the measured COP was the optimum value were obtained. In this case, the indoor-side suction dry bulb temperature is 20.00 to 20.02 ° C., the indoor-side suction wet bulb temperature is 11.50 to 11.69 ° C., and the outdoor-side suction dry bulb temperature is 6.95 to 6.98. The outdoor suction wet bulb was maintained at 5.96 to 6.00 ° C. Air flow of the refrigerant A when measured COP value is the optimum value is 7.95m ³ / min, air volume of the refrigerant B was 8.10m ³ / min.

As shown in Table 1, when refrigerants A and B were used (Examples 6 to 9), it was possible to achieve an actual measured COP that was superior to when R410A (Comparative Example 2) was used. Moreover, when the refrigerant | coolant B and the refrigerant | coolant A were compared, the refrigerant | coolant B showed the heating capability and heating actual measurement COP which were more excellent.
Further, the _{COP RH} (7/35 ℃) calculated by the _{method, COP RH (7/35 ℃} ) / {ρL (35 ℃) × (1 / ρV (35 ℃)}, COP RH (0/50 ℃ ) And COP _RH (0/50 ° C.) / {ΡL (50 ° C.) × (1 / ρV (50 ° C.)} are shown in Table 1.

（注１）各成分の含有量の測定はＪＩＳ Ｋ２２４０の方法による。
（注２）実測ＣＯＰ(実測のCoefficient of Performance)は次式により算出した。
実測ＣＯＰ＝（空調機の冷暖房能力）／（空調機消費電力）
（注３）記号の意味は前記の意味を示す。

(Note 1) The content of each component is measured according to the method of JIS K2240.
(Note 2) Measured COP (actually measured Coefficient of Performance) was calculated by the following equation.
Measured COP = (air conditioning capacity) / (air conditioner power consumption)
(Note 3) The meanings of the symbols are as described above.

  In Table 1, the air conditioning capacity of the air conditioner was measured by the indoor air enthalpy method. That is, it was calculated by (1) measurement of temperature / humidity with a dry bulb / wet bulb thermometer installed outside and inside the laboratory, and (2) measurement of the air volume at the air outlet of the air conditioner in the laboratory.

[Test Example 3] <Freezing and refrigeration test>
The freezing and refrigeration test was conducted in a freezing warehouse equipped with a MITSUBISHI (type ER-Z5A1 scroll compressor type: 7.5 kW, amount of refrigerant R22 is about 20 Kg) using R22 which is an HCFC refrigerant. The size of the warehouse was 15 tsubo and the height to the ceiling was about 3 m. The R22 was operated from November 14, 2006 to November 16, 2006, and the power consumption (kWh) per 24 hours was measured (Comparative Example 3). The internal temperature was about −25 ° C.

  Thereafter, refrigerant R22 was replaced with refrigerant B (about 12 kg), and the freezer was operated from November 22, 2006 to January 22, 2007, and the power consumption per 24 hours was measured (implementation) Example 10). Moreover, the inside temperature was -20 degreeC--25 degreeC vicinity except the day which stopped the business.

  FIG. 4 shows changes in power consumption of R22 and refrigerant B obtained in the test. In FIG. 4, the graph in black is Example 10. The average power consumption amount of R22 and refrigerant B is 124.6 kWh / day when R22 is used as a refrigerant, and the average power consumption when refrigerant B is used is 284.6 kWh / day. The value was 81.7 kWh / day, which was a value less than about 40 kWh per day. As a result, if the power consumption of R22 is 100%, the power consumption of the refrigerant B is 65.6%. By replacing refrigerant B in a refrigerator designed with R22 as the refrigerant, almost the same cooling capacity was obtained with about 2/3 of the conventional power consumption. From this, it has been found that not only the air conditioner for home use but also the commercial refrigerator can greatly contribute to energy saving by changing the refrigerant from R22 to refrigerant B without changing the existing equipment.

[Test Example 4] <Freezing and refrigeration test>
A freezing and refrigeration test using refrigerant B was performed with a container MOLU5544039 (container B, 20 feet) manufactured by Nippon Full Half Co., Ltd. equipped with LXE5C-1 manufactured by Daikin Industries, Ltd. as a refrigerator.

  About 4 kg of refrigerant R134a, which is an HFC refrigerant, was extracted from the refrigerator of container B, and then charged with 1.08 kg of refrigerant B (Example 11). As a control, a freezing and refrigeration test using refrigerant R134a was conducted by Nippon Full Half Co., Ltd. container MOLU55446957 (container A, 20 feet) equipped with LXE5C-1 manufactured by Daikin Industries, Ltd. as a refrigerator (Comparative Example 4). .

  Both containers were set at 5 ° C. and operated simultaneously. The container temperature and power consumption were measured. The results are shown in FIG. In FIG. 5, the graph indicated by hatching is the power consumption of Example 11. In the figure, the characteristic curve L is the internal temperature of Example 11, and the characteristic curve M is the internal temperature of Comparative Example 4. While the power consumption of the refrigerant B of Example 7 was slightly higher, the container temperature tended to be lower for the refrigerant B. As a result, it was confirmed that the refrigerant B can be sufficiently used in place of the refrigerant 134a.

[Test Example 5] <Freezing and refrigeration test>
As a refrigerator used in Test Example 4, a container MOLU5544039 (container B) manufactured by Nippon Full Half Co., Ltd. equipped with LXE5C-1 manufactured by Daikin Industries, Ltd. is used, and the refrigerator A is used for this refrigerator. A test was conducted (Example 12).

  After extracting the refrigerant B from the refrigerator of the container B, 1.7 kg of the refrigerant A was filled. As a control, a freezing and refrigeration test using refrigerant R134a was performed using a container MOLU55446957 (container A) manufactured by Nippon Full Half Co., Ltd. equipped with LXE5C-1 manufactured by Daikin Industries, Ltd. as a refrigerator (Comparative Example 5).

  Both containers were set at 5 ° C. and operated simultaneously. The container temperature and power consumption were measured. The results are shown in FIG. In FIG. 6, the hatched graph is the power consumption of Example 12. In the figure, the characteristic curve P is the container internal temperature of Example 8, and the characteristic curve Q is the container internal temperature of Comparative Example 5. The temperature inside the container was lower in the refrigerant A, and the power consumption was slightly lower in the refrigerant A. As a result, it was confirmed that the refrigerant A could be used in place of the refrigerant 134a.

[Calculation example]
Table 2 shows a calculation example of the composition of the propane binary hydrocarbon mixed refrigerant having high refrigeration and air conditioning performance, and Table 3 shows a calculation example of the composition of the propane multi-dimensional hydrocarbon mixed refrigerant having high refrigeration and air conditioning performance. The calculation method is described in the detailed description of the invention.

Industrial applicability

  The present invention can replace the substitute chlorofluorocarbon with a natural refrigerant, reduce the substitute chlorofluorocarbon, which is a greenhouse gas, and save energy in the refrigeration and refrigeration and air-conditioning air conditioning equipment. It contributes to the prevention of global warming by both energy saving and can be used for freezing and refrigeration and air conditioning with air conditioning.

Claims (5)

Propane content is 55 to 98 mol%, propylene content is 0.8 or less in molar ratio to the total content of propane and propylene, and methane, ethylene, ethane, propyne, cyclopropane, butene, isobutene A hydrocarbon mixed refrigerant containing at least one selected from
The saturated vapor pressure at 7 ° C. is 0.3 to 1 MPa, the saturated vapor pressure at 35 ° C. is 0.6 to 2.2 MPa, the boiling point is −20 ° C. or less, and one of the formulas (V) to (IX) A hydrocarbon mixed refrigerant characterized by satisfying two or more.
COP _RC (7 ° C./35° C.) / {ΡL (7 ° C.) × (1 / ρV (7 ° C.))} ≧ 4.6... Formula (V)
[In the formula, COP _RC (7 ° C / 35 ° C): Theoretical cooling performance coefficient of a refrigeration cycle with an evaporation temperature of 7 ° C and a condensation temperature of 35 ° C ρL (7 ° C): 7 ° C, or if it is non-azeotropic Saturated vapor pressure at 7 ° C and saturated liquid density at equal pressure (kg / l) ρV (7 ° C): saturated vapor density at 7 ° C (mol-kg / m ³ )]
COP _RH (7 ° C./35° C.) / {ΡL (35 ° C.) × (1 / ρV (35 ° C.))} ≧ 11.9... Formula (VI)
[In the formula, COP _RH (7 ° C./35° C.): Theoretical heating coefficient of performance of a refrigeration cycle having an evaporation temperature of 7 ° C. and a condensation temperature of 35 ° C. ρL (35 ° C.): 35 ° C. Saturated vapor pressure at 35 ° C. and saturated liquid density at equal pressure (kg / l) ρV (35 ° C.): saturated vapor density at 35 ° C. (mol-kg / m ³ )]
COP _RC (0 ° C./50° C.) / {ΡL (0 ° C.) × (1 / ρV (0 ° C.))} ≧ 1.7 Formula (VII)
[In the formula, COP _RC (0 ° C./50° C.): theoretical cooling coefficient of performance of a refrigeration cycle with an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C. ρL (0 ° C.): 0 ° C. Saturated vapor pressure at 0 ° C. and saturated liquid density at equal pressure (kg / l) ρV (0 ° C.): saturated vapor density at 0 ° C. (mol-kg / m ³ )]
COP _RH (0 ° C./50° C.) / {ΡL (50 ° C.) × (1 / ρV (50 ° C.))} ≧ 9.6 ··· formula (VIII)
[In the formula, COP _RH (0 ° C./50° C.): Theoretical heating coefficient of performance of a refrigeration cycle having an evaporation temperature of 0 ° C. and a condensation temperature of 50 ° C. ρL (50 ° C.): 50 ° C. 50 ° C. saturated vapor pressure and equal pressure saturated liquid density (kg / l) ρV (50 ° C.): 50 ° C. saturated vapor density (mol-kg / m ³ )]
COP _RC (−15 ° C./30° C.) / {ΡL (−15 ° C.) × (1 / ρV (−15 ° C.))} ≧ 1.2 (Equation (IX))
[In the formula, COP _RC (−15 ° C./30° C.): Theoretical cooling performance coefficient of a refrigeration cycle having an evaporation temperature of −15 ° C. and a condensation temperature of 30 ° C. ρL (−15 ° C.): −15 ° C., or non-azeotropic In the case of the nature, saturated vapor density of -15 ° C and saturated liquid pressure (kg / l) ρV (-15 ° C): saturated vapor density of -15 ° C (mol-kg / m ³ )] 2. The hydrocarbon mixed refrigerant according to claim 1, wherein the ethane content is 2 to 25 mol%. The hydrocarbon mixed refrigerant according to any one of claims 1 and 2, wherein the methane content is 2 to 25 mol%. Ethylene content of 2
The hydrocarbon mixed refrigerant according to claim 1, wherein the hydrocarbon mixed refrigerant is 30 mol%. Furthermore, the total content of n-butane and isobutane is 1 to 24 mol%, the content of n-butane is 19 mol% or less, and the content of isobutane is 12 mol% or less. 5. The hydrocarbon mixed refrigerant according to any one of 4 above.

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