Refrigeration system and method

Abstract

Refrigerant and refrigeration systems are disclosed, including a cascade refrigeration system comprising: a plurality of refrigeration units, each refrigeration unit comprising a first refrigeration circuit, each first refrigeration circuit comprising an evaporator and a heat exchanger; and a second refrigeration circuit; wherein each first circuit heat exchanger is arranged to transfer thermal energy between its respective first and second refrigeration circuits.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is related to the following applications and each of which is incorporated by reference: U.S. Provisional Application No. 63 / 344,542 filed on May 21, 2022 and U.S. Provisional Application No. 63 / 432,882 filed on December 15, 2022. Technical Field

[0003] The present invention relates to high efficiency, low global warming potential ("low GWP") refrigerants, and to air conditioning and / or refrigeration systems and methods that provide safe and efficient cooling. Specific embodiments relate to commercial refrigeration and cascade refrigeration systems and methods, particularly but not exclusively to commercial refrigeration (including commercial cascade refrigeration systems and methods) that have excellent performance when using certain low GWP refrigerants. Background Art

[0004] The refrigeration industry is facing increasing pressure - through regulatory changes or other means - to replace relatively high global warming potential (GWP) refrigerants, such as HFC-134a and R404A, with materials with lower GWP values. Under many current regulations and future anticipated regulations, refrigerants are required to have a GWP value of less than 150. The use of refrigerants with a GWP value of less than 150 is particularly important in commercial refrigeration systems because the refrigerants are used in large quantities and in such use, the potential negative environmental impact is very large if refrigerants with significantly higher GWP values ​​are used.

[0005] One approach in the past has been to use low GWP refrigerants, such as carbon dioxide (R744) and hydrocarbon refrigerants. However, such approaches that have been used to date may suffer from significant safety and financial disadvantages, such as: poor system energy efficiency, resulting in increased operating costs; high system complexity, resulting in high initial system costs; low system maintainability and reliability, resulting in high maintenance costs; and high system flammability. Systems that include highly flammable refrigerants according to existing arrangements are particularly disadvantageous because they can result in poor safety levels; may conflict with regulatory code restrictions; and can increase the liability of refrigeration system operators and manufacturers. Safety is a particular concern considering that many commercial refrigeration applications (such as supermarket refrigerators, freezers, and cold display cases) are accessible to the public and often operate in densely populated spaces.

[0006] Another approach is to provide new refrigerants with a GWP lower than HFC-134a, but this approach often fails to successfully produce refrigerants with a GWP of 150 or less. For example, U.S. Patent Application 2021 / 0198547 discloses an attempt to provide a refrigerant with a GWP less than HFC-134a by using a refrigerant blend comprising HFO-1234ze(E) and HFC-134, which also provides an efficiency of use equal to or higher than HFC-134a. However, this effort was not fruitful because it did not show the ability to provide a refrigerant with a GWP less than 150 that also provided other desired qualities, such as non-flammability and good heat transfer properties. Specifically, the '547 application discloses 11 specific refrigerant blends, and all of those refrigerant blends have a GWP greater than 300. Therefore, at least in this sense, the refrigerants of the '547 application do not achieve the combination of properties that are intended as a preferred aspect of the present invention, including a GWP of less than 150. For example, a refrigerant comprising 63 wt % HFO-1234ze(E), 35 wt % HFC-134, and 2 wt % R1244yd is disclosed, but the refrigerant blend has a GWP of 389. Similar ineffective results are disclosed for ten (10) other blends specifically disclosed in the '547 application.

[0007] Applicants have therefore recognized that there remains a need in the refrigeration industry for safe, robust and sustainable methods to reduce the use of high GWP refrigerants that can be used with existing technologies, and in particular, there is a need for a refrigerant with a GWP of less than 150 while providing 65% or greater capacity, non-flammability and relatively low glide compared to existing refrigerants (including R-134a).

[0008] The prior art is also seeking to have improved cascade refrigeration systems which can provide environmentally advantageous operation. Fig. 6A As shown, an example of a typical cascade refrigeration system is system 100, which is a type of commercial refrigeration commonly used in supermarkets. System 100 is a direct expansion system that provides both medium-temperature and low-temperature refrigeration via a medium-temperature refrigeration circuit 110 and a low-temperature refrigeration circuit 120. In such a typical configuration, the medium-temperature refrigeration circuit 110 has R134a as its refrigerant. The medium-temperature refrigeration circuit 110 provides medium-temperature cooling and removes waste heat from the low-temperature refrigeration circuit 120 via a heat exchanger 130. The medium-temperature refrigeration circuit 110 extends between the top plate 140, the machine room 141 and the sales area 142. On the other hand, the low-temperature refrigeration circuit 120 has R744 as its refrigerant. The low-temperature refrigeration circuit 120 extends between the machine room 141 and the sales area 142. Available, as discussed above, R744 has a low GWP.

[0009] However, although Fig. 6A Refrigeration systems of the type disclosed in the specification may be capable of providing good efficiency levels, but the applicant has recognized that systems of this type have at least two major disadvantages: first, such systems use the high GWP refrigerant R134a (R134a has a GWP of approximately 1300); second, although the low temperature portion of such systems uses the low GWP refrigerant R744, this refrigerant exhibits many of the above-mentioned disadvantages, including significant safety and financial disadvantages.

[0010] In addition, in certain refrigeration applications, it is necessary to cool products without exposing those products to temperatures below a certain temperature (such as the freezing point of water). For example, in a supermarket environment, it is often disadvantageous to keep certain products at a reduced temperature relative to the environment, but it is disadvantageous to cool the products to below the freezing point of water at the same time, especially because the preferred cooling method includes indirect cooling with humid ambient air. For these applications, it is also disadvantageous to have a refrigerant temperature below the freezing point of water along the evaporator, because they will cause frost accumulation, and therefore require defrosting the equipment. Avoiding frost accumulation is an important aspect in those applications. Similarly, the cooling of beverages (including water, etc.) should also be carried out under conditions that avoid exposing such products to temperatures below the freezing point of water, because it is not desirable to freeze such products when they are sold. For convenience, the applicant refers to such applications, methods and systems as "non-freezing" applications, methods and systems herein.

[0011] Certain single component fluorocarbons, including chlorofluorocarbons ("CFCs"), hydrochlorofluorocarbons ("HCFCs"), and hydrofluoroolefins ("HFOs"), have been used in "frost-free" applications where the refrigerant temperature along the evaporator must be maintained above the freezing point of water so that frost does not accumulate on the coil surfaces, and thus, in such refrigeration applications, systems and methods, no defrost is required. It has heretofore been considered particularly desirable to use single component fluids because the saturation temperature of such fluids does not change as the fluid evaporates at a constant pressure. This is highly desirable because it allows a system or method to be designed with a refrigerant temperature along the evaporator that remains substantially constant during the evaporation process and above the freezing temperature of water, assuming little or no pressure drop as the refrigerant flows through the evaporator. In addition, product applications also typically require a small temperature differential between the air and the refrigerant to reduce dehumidification of the air, and subsequent removal of moisture content and quality loss of the product. The requirements of a small temperature differential and avoidance of frost formation, as well as the need for the evaporator to have a certain positive superheat at the outlet, are critical in selecting a particular refrigerant. Superheat at or below zero (i.e., the refrigerant is not overheated) can result in reduced cooling capacity, efficiency, and potential compressor failure. The term "superheat" or simply "superheat" refers to the temperature of the refrigerant at the evaporator outlet rising above the saturated vapor temperature (or dew point temperature) of the refrigerant.

[0012] This is Figure 6B 6, a typical supermarket product cooling case is shown in schematic form. Typically, as shown in FIG. 6, cooled, humidified air is provided to the product display area of ​​the display case by passing air from the outside of the cabinet 102 and recirculated air 104 through the heat exchange surface of the evaporator coil 106, which is arranged in an area within the display case that is usually separated from the product display area (or at least not visible to consumers) but close to the product display area. The evaporator 106 has a single-component refrigerant inlet 108 and a single-component refrigerant outlet 110. A circulating fan 114 is also used. In systems of the above type, it is highly desirable that the cooling space 112 in the refrigeration system has a refrigerant temperature that is always or substantially always above a certain level along the evaporator. For example, in many applications such as refrigeration of products, the minimum discharge (outlet) temperature of the air in the display case is designed to be about 2°C to 3°C in order to provide a safety margin for avoiding having a cooling space or cooling products that are below the freezing point of water. Furthermore, to minimize the removal of moisture from the air and subsequent drying of the product (mass loss), the temperature difference between the air outlet and the refrigerant needs to be small, typically 2° C. to 3° C. This, combined with the fact that the evaporator for these applications requires a superheat of about 3° C. to about 5° C., will impose a constraint on the allowable evaporator glide of the refrigerant so that the evaporation temperature remains above the freezing point of water and so frost does not accumulate.

[0013] Those skilled in the art will appreciate that these two desired results have heretofore been difficult to provide for refrigerants that are multi-component blends of different single component refrigerants.

[0014] For example, although HFC-134a has been used in certain non-refrigeration applications to date, it cannot meet, for example, the low GWP requirement (item 4 above) because HFC-134a has a GWP of about 1,300.

[0015] Applicants have proceeded in a manner contrary to accepted thinking and have discovered unexpected and advantageous results. For example, Applicants have discovered, as described in detail below, that particular blends comprising carefully selected combinations of components can have an advantageous but unexpected combination of non-flammability, while having excellent heat transfer properties, low GWP (e.g., a GWP of less than about 150), low or no toxicity, chemical stability, and lubricant compatibility, among other properties. In addition, Applicants have discovered that the refrigerant compositions of the present invention are particularly advantageous for use in medium temperature refrigeration systems, particularly in medium temperature refrigeration systems where it is desirable to maintain the temperature of the cold air above about 0°C, and in other specific embodiments where it is also desirable to avoid exposing the air being cooled to temperatures below about 0°C, in order to protect the cooled articles from frost and / or to prevent frost on the evaporator coils, which in itself can have a negative impact on the overall efficiency of such systems due to the need for defrosting and / or inconsistent cooling between coils.

[0016] As detailed herein, the present invention satisfies one or more of these needs as well as other unmet needs in the prior art. Summary of the invention

[0017] Applicants have discovered refrigerant compositions, heat transfer compositions containing the refrigerants, refrigeration methods and systems, including cascade heat transfer methods and systems, and / or methods and systems for cooling materials having cryogenic limitations, such as the cryogenic or non-refrigeration applications described above.

[0018] The present invention also provides medium temperature refrigeration systems and methods, as well as commercial refrigeration systems and methods, as described in detail below.

[0019] The refrigerants of the present invention preferably have a GWP of less than about 150, are classified by ASHRAE as A1 (non-flammable and low toxicity), and have an evaporator glide of less than 4.5° C., or less than about 4° C., or less than about 3.5° C., or less than 2.5° C. This means that the refrigerants of the present invention according to such embodiments are able to achieve unexpectedly small changes in refrigerant temperature through the evaporator.

[0020] The present invention also includes a refrigerant consisting essentially of:

[0021] from about 75 wt. % to about 86 wt. % HFO-1234ze(E),

[0022] 5 wt % to less than 11 wt % HFC-134a; and

[0023] About 5 wt % to about 16 wt % HFO-1224yd (Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 1 for convenience.

[0024] The present invention also includes a refrigerant consisting essentially of:

[0025] 74 to 86 wt. % HFO-1234ze(E),

[0026] 5 wt % to 10 wt % or less of HFC-134a; and

[0027] 4 wt % to 16 wt % HFO-1224yd(Z).The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 2 for convenience.

[0028] The present invention also includes a refrigerant consisting essentially of:

[0029] 76 to 86 wt. % HFO-1234ze(E),

[0030] About 10 wt. % or less of HFC-134a; and

[0031] 4 wt % to 14 wt % HFO-1224yd(Z).The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 3 for convenience.

[0032] The present invention also includes a refrigerant consisting essentially of:

[0033] about 78 to 86 weight percent HFO-1234ze(E),

[0034] About 10 wt. % or less of HFC-134a; and

[0035] 4 wt % to about 12 wt % HFO-1224yd(Z).The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 4 for convenience.

[0036] The present invention also includes a refrigerant consisting essentially of:

[0037] About 84% by weight of HFO-1234ze(E),

[0038] 10 wt% or less of HFC-134a; and

[0039] About 6 wt % HFO-1224yd(Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 5 for convenience.

[0040] The present invention also includes a refrigerant consisting of:

[0041] About 82% by weight of HFO-1234ze(E),

[0042] 10 wt% or less of HFC-134a; and

[0043] About 8 wt % HFO-1224yd (Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 6 for convenience.

[0044] The present invention also includes a refrigerant consisting of:

[0045] About 80% by weight of HFO-1234ze(E),

[0046] 10 wt% or less of HFC-134a; and

[0047] About 10 wt. % HFO-1224yd (Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 7 for convenience.

[0048] The present invention also includes a refrigerant consisting essentially of:

[0049] 84 wt% + 2 wt% / - 2 wt% HFO-1234ze (E),

[0050] 10 wt% + 0.5 wt% / - 2 wt% HFC-134a; and

[0051] 6 wt% + 2 wt% / - 2 wt% HFO-1224yd (Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 8A for convenience.

[0052] The present invention also includes a refrigerant consisting essentially of:

[0053] 83.5 wt.% + 0.5 wt.% / - 2 wt.% HFO-1234ze (E),

[0054] 10 wt% + 2 wt% / - 0.5 wt% HFC-134a; and

[0055] 6.5 wt% + 2 wt% / - 0.5 wt% HFO-1224yd (Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 8B for convenience.

[0056] The present invention also includes a refrigerant consisting of:

[0057] 83.5 wt.% + 0.5 wt.% / - 2 wt.% HFO-1234ze (E),

[0058] 10 wt% + 2 wt% / - 0.5 wt% HFC-134a; and

[0059] 6.5 wt% + 2 wt% / - 0.5 wt% HFO-1224yd (Z). The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 8C for convenience.

[0060] The present invention also includes a refrigerant consisting essentially of:

[0061] from about 74 wt. % to about 86 wt. % HFO-1234ze(E),

[0062] 5 wt % to less than 12 wt % HFC-134a; and

[0063] About 4 wt % to about 16 wt % HFO-1224yd(Z), provided that the refrigerant has an evaporator glide of 4.5°C or less, a GWP of less than 150 and is a Class A1 non-flammable refrigerant. The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 9 for convenience.

[0064] The present invention also includes a refrigerant consisting essentially of:

[0065] about 76 to 86 weight percent HFO-1234ze(E),

[0066] 5 wt % to less than 12 wt % HFC-134a; and

[0067] About 4 wt % to about 14 wt % HFO-1224yd(Z), provided that the refrigerant has an evaporator glide of 4°C or less, a GWP of less than 150 and is a Class A1 non-flammable refrigerant. The refrigerant according to this paragraph is sometimes referred to herein as Refrigerant 10 for convenience.

[0068] The present invention includes a method for providing cooling, the method comprising:

[0069] a. Provide a vapor compression refrigeration system, which includes a compressor, a condenser, an evaporator and a refrigeration

[0070] The refrigerant comprises:

[0071] i. about 74 wt % to about 86 wt % HFO-1234ze(E),

[0072] ii. less than 12 wt% HFC-134a; and

[0073] iii. about 4 wt % to about 16 wt % HFO-1224yd(Z); and

[0074] b. evaporating the refrigerant in the evaporator, wherein the refrigerant in the evaporator

[0075] The glide in the system is 4.5°C or less, and wherein the capacity of the refrigerant in the system is greater than 65% of the capacity of R-134a in the system.

[0076] The method according to this paragraph is sometimes referred to herein as heat transfer method 1 for convenience.

[0077] The present invention includes a method for providing cooling, the method comprising:

[0078] a. Providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator and a refrigerant according to any one of refrigerants 1 to 10; and

[0079] b. evaporating the refrigerant in the evaporator, wherein the refrigerant in the evaporator

[0080] The glide in the system is 4.5°C or less, and wherein the capacity of the refrigerant in the system is greater than 65% of the capacity of R-134a in the system.

[0081] The method according to this paragraph is sometimes referred to herein as Heat Transfer Method 2 for convenience.

[0082] The present invention includes a method for providing cooling, the method comprising:

[0083] a. Provide a vapor compression refrigeration system, which includes a compressor, a condenser, an evaporator and a refrigeration

[0084] The refrigerant comprises:

[0085] i. 65 wt% to less than 85 wt% of HFO-1234ze(E),

[0086] ii. less than 12 wt% HFC-134a; and

[0087] iii. about 10 wt % to about 22 wt % HFO-1336mzz(E); and

[0088] b. evaporating the refrigerant in the evaporator,

[0089] Wherein the refrigeration system comprises a high temperature heat pump system or an extreme temperature air conditioning system. The method according to this paragraph is sometimes referred to herein as heat transfer method 3A for convenience.

[0090] The present invention includes a method for providing cooling, the method comprising:

[0091] a. Providing a vapor compression refrigeration system, comprising a compressor, a condenser, an evaporator and a refrigerant, the refrigerant comprising:

[0092] i. 70 wt% to less than 80 wt% of HFO-1234ze(E),

[0093] ii. less than 11 wt% HFC-134a; and

[0094] iii. about 10 wt % to about 15 wt % HFO-1336mzz(E); and

[0095] b. evaporating the refrigerant in the evaporator,

[0096] Wherein the refrigeration system comprises a high temperature heat pump system or an extreme temperature air conditioning system. The method according to this paragraph is sometimes referred to herein as heat transfer method 3B for convenience.

[0097] The present invention includes a method for providing cooling, the method comprising:

[0098] a. Providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator and a refrigerant consisting essentially of HDR165; and

[0099] b. evaporating the refrigerant in the evaporator,

[0100] Wherein the refrigeration system comprises a high temperature heat pump system or an extreme temperature air conditioning system. The method according to this paragraph is sometimes referred to herein as heat transfer method 3C for convenience.

[0101] As used herein, reference to a defined system or method or refrigerant, etc., by referring to a series of defined numbered systems, methods, refrigerants, etc. (such as heat transfer methods 1 to 3), includes all methods so defined, including any numbered methods with a suffix, such as heat transfer methods 1 to 3 means specifically including each of heat transfer method 1, heat transfer method 2, heat transfer method 3A, heat transfer method 3B and heat transfer method 3C.

[0102] The present invention includes a cascade refrigeration system comprising (a) a low-grade refrigeration circuit including: (i) a low-grade refrigerant, preferably having a GWP of about 150 or less; and (b) a compressor; (c) an inter-circuit heat exchanger in which the low-grade refrigerant condenses; and (d) a high-grade refrigeration circuit including a high-grade refrigerant that: (i) has a Class 1A or Class A2L flammability; and (ii) evaporates at a temperature below the condensation temperature of the low-grade refrigerant; and (iii) contains at least about 74 weight percent HFO-1234ze(E), wherein the high-grade refrigerant evaporates in the inter-circuit heat exchanger by absorbing heat from the refrigerant in the low-grade refrigeration circuit. Such cascade refrigeration circuits are described in detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0103] Figure 1 is a schematic diagram of an exemplary heat transfer system that can be used for air conditioning, low temperature refrigeration, and medium temperature refrigeration.

[0104] Figure 2 is a schematic diagram of an exemplary heat transfer system that may be used for low and medium temperature refrigeration and includes a vapor ejector.

[0105] Figure 3 is a schematic diagram of an exemplary heat transfer system that may be used for low and medium temperature refrigeration and includes a liquid ejector.

[0106] Figure 4 is a schematic diagram of an exemplary heat transfer system that may be used for low and medium temperature refrigeration and includes a suction line / liquid line heat exchanger.

[0107] Figure 5 is a schematic diagram of an exemplary heat transfer system that may be used for low and medium temperature refrigeration and includes a steam ejector and an oil separator.

[0108] Fig. 6A A typical cascade refrigeration system is shown in schematic form.

[0109] Figure 6B A typical supermarket produce cooling cabinet is shown in schematic form.

[0110] Figure 7 A cascade refrigeration system useful in accordance with the present invention is shown.

[0111] Figure 8 An alternative cascade refrigeration system useful in accordance with the present invention is shown. DETAILED DESCRIPTION

[0112] definition:

[0113] As used herein, the terms "lower stage" and "higher stage" are used in a relative context to refer to the relative evaporation temperatures of two or more cascade refrigeration circuits. Thus, in the context of a cascade refrigeration system, the term "lower stage" refers to a refrigeration circuit in which the refrigerant evaporation temperature is lower than the refrigerant evaporation temperature in the "higher stage".

[0114] As used herein, the term "cascade refrigeration" refers to a refrigeration system having a low-grade refrigerant vapor that is cooled, and preferably condensed, at least in part by rejecting heat to a high-grade refrigerant.

[0115] The phrase "coefficient of performance" (hereinafter referred to as "COP") is a measure of generally accepted refrigerant performance, and is particularly useful for representing the relative thermodynamic efficiency of a refrigerant in a specific heating or cooling cycle involving refrigerant evaporation or condensation. In refrigeration engineering, the term represents the ratio of available refrigeration or cooling capacity to the energy applied by the compressor when compressing vapor, and therefore represents the ability of a given compressor to pump heat for a given volume flow of heat transfer fluid such as a refrigerant. In other words, given a specific compressor, a refrigerant with a higher COP will deliver more cooling or heating power. A method for estimating the COP of a refrigerant under specific operating conditions is to estimate from the thermodynamic properties of the refrigerant using standard refrigeration cycle analysis techniques (see, for example, RC Downing, "FLUOROCARBONREFRIGERANTS HANDBOOK", Chapter 3, Prentice-Hall, 1988, which is incorporated herein by reference in its entirety) from the thermodynamic properties of the refrigerant.

[0116] The phrase "global warming potential" (hereinafter "GWP") was created to allow comparison of the global warming impact of different gases. It compares the heat trapped by a certain mass of a gas over a specific time period to the heat trapped by a similar mass of carbon dioxide. Carbon dioxide was selected by the Intergovernmental Panel on Climate Change (IPCC) as the reference gas and its GWP was taken to be 1. The greater the GWP, the warmer the earth will be made by a given gas compared to CO2 over that time period. As used herein, the term GWP refers to the global warming potential of a given gas according to the IPCC Fifth Assessment Report 2014. 1 (IPCC Fifth Assessment Report, 2014 11 ) measured GWP values, which is referred to and abbreviated as AR5 in this article.

[0117] The term "nonflammable" means a compound or composition that is determined to be nonflammable under the conditions described in ASHRAE Standard 34-2016 Nomenclature and Safety Classification of Refrigerants and in Appendix B1 of ASHRAE Standard 34-2016 according to ASTM Standard E-681-2009 Standard Test Method for Flammable Concentration Limits of Chemicals (Vapor and Gases) (as various standards existed prior to the filing date of this application), which is incorporated herein by reference in its entirety (the "Nonflammability Test"). Flammability is

[0118] Defined as the ability of a composition to ignite and / or propagate a flame. Under this test, flammability is determined by measuring the flame angle. Non-flammable materials are classified as Class "1" by the definition of conditions and apparatus in ASHRAE Standard 34-2016, Test Procedure for Nomenclature and Safety Classification of Refrigerants, and using current method ASTM E681-09 Annex A1 (each as of the date of filing of this application).

[0119] As used herein, the term "evaporator glide" refers to the difference between the saturation temperature of the refrigerant at the evaporator inlet and the dew point of the refrigerant at the evaporator outlet, assuming that the pressure at the evaporator outlet is the same as the pressure at the inlet. As used herein, the phrase "saturation temperature" refers to the temperature at which a liquid refrigerant boils into vapor at a given pressure.

[0120] As used herein, the phrase "non-toxic or low toxicity" means that the composition is classified as Class "A" by ASHRAE Standard 34-2016 Nomenclature and Safety Classification of Refrigerants and is described in Appendix Bl of ASHRAE Standard 34-2016 (as various standards existed prior to the filing date of this application).

[0121] Non-flammable and low toxicity materials are classified as "A1" by ASHRAE Standard 34-2016 Nomenclature and Safety Classification of Refrigerants and are described in ASHRAE Standard 34-2016 Appendix B1 (as various standards existed prior to the filing date of this application).

[0122] The term "superheat" or simply "superheat" refers to the temperature of the refrigerant at the evaporator outlet rising above the saturated vapor temperature (or dew point temperature) of the refrigerant.

[0123] As used herein, the term "E-1,3,3,3-tetrafluoropropene" refers to the trans isomer of HFO-1234ze and is abbreviated as HFO-1234ze(E).

[0124] As used herein, the term "Z-1-chloro-2,3,3,3-tetrafluoropropene" refers to the cis isomer of HFCO-1224yd and is abbreviated as HFCO-1224yd(Z).

[0125] As used herein, the term "1,1,1,2-tetrafluoroethane" is abbreviated as HFC-134a.

[0126] As used herein, the term "1,1,2,2-tetrafluoroethane" is known in the industry by the abbreviation HFC-134 and is abbreviated herein as HFC-134.

[0127] As used herein, the term "E-1,1,1,4,4,4-hexafluorobut-2-ene" refers to the trans isomer of HFO-1336mzz and is abbreviated as HFO-1336mzz(E).

[0128] As used herein, the term "1,1,1,2,3,3,3-heptafluoropropane" is abbreviated as HFC-227e.

[0129] As used herein, the term "difluoromethane" refers to CH2F2 and is abbreviated as HFC-32.

[0130] As used herein, the term "low temperature refrigeration" refers to a refrigeration system operating under the following conditions or ranges: (a) a condenser temperature of about 15°C to about 50°C; and (b) an evaporator temperature of about -40°C to about or less than about -15°C.

[0131] As used herein, the term "medium temperature refrigeration" refers to a refrigeration system utilizing one or more compressors and operating under the following conditions or ranges: (a) a condenser temperature of about 15°C to about 60°C; and (b) an evaporator temperature of about -15°C to about 5°C.

[0132] As used herein, the term "extreme temperature air conditioning system" refers to a vapor compression air conditioning system in which the condensing temperature of the refrigerant is from about 55°C to about 95°C.

[0133] As used herein, the term "high temperature heat pump system" refers to a vapor compression system operable in a heating mode wherein the condensing temperature of the refrigerant is from about 55°C to about 95°C.

[0134] As used herein, the term "R454C" refers to a refrigerant designated by ASHRAE as 454C, which is composed of 21.5% + 2 / - 2% R-32 and 78.5 + 2 / - 2% HFC-1234yf.

[0135] As used herein, the term "R455A" refers to a refrigerant designated by ASHRAE as 455AC, which consists of 21.5%+2 / -1% R-32, 75.5% HFC-1234yf+2 / -2% and 3%+2 / -1% CO2.

[0136] As used herein, the term "R471A" refers to a refrigerant designated 471A by ASHRAE, which consists of 78.7%+0.4 / -1.5% HFC-1234ze(E), 17%+1.5 / -0.4% HFC-1336mzz(E) and 4.3%+1.5 / -0.4% HFC-227ea.

[0137] As used herein, the term "HDR165" refers to a refrigerant composed of 78.7% + / - +0.5 / - 2% HFC-1234ze(E), 12% +2 / - 0.5% HFC-1336mzz(E), and 10% +2 / - 0.5% HFC-134a.

[0138] As used herein, the term "HDR166" refers to a refrigerant composed of 83.5%+0.5 / -2% HFC-1234ze(E), 6.5+2% / -0.5% HFCO-1224yd(Z), and 10%+2% / -0.5% HFC-134a.

[0139] As used herein, the term "about" in connection with an amount expressed as a weight percent means that the amount of the component may vary by + / - 2 weight percent.

[0140] Refrigerant and Heat Transfer Compositions:

[0141] Applicants have discovered that the refrigerants of the present invention (including each of Refrigerants 1 to 10 as described herein) are unexpectedly able to provide an exceptionally advantageous set of properties, including: excellent heat transfer properties (including relatively high capacity, i.e., greater than 65% relative to HFC-134a), acceptable toxicity and non-flammability (i.e., Class 1A), zero or near zero ozone depletion potential ("ODP"), relatively low evaporator glide, and lubricant compatibility, including miscibility with POE and / or PVE lubricants over the operating temperature and concentration ranges used in medium and low temperature refrigeration systems, cascade refrigeration systems, transport refrigeration systems, and heat pumps.

[0142] The particular advantage of the refrigerants of the present invention (specifically including each of refrigerants 1 to 10) is that they are non-flammable and have acceptable toxicity, that is, each is a Class A1 refrigerant. Those skilled in the art will appreciate that the flammability of a refrigerant may be a characteristic considered in certain important heat transfer applications, and that a refrigerant classified as Class A1 may generally be superior to a non-Class A1 refrigerant. Therefore, it is desirable in the art to provide a refrigerant composition that can be used as a replacement for previous non-flammable refrigerants such as R-22, R404A, R407F, R448A, R449A or R-134a, having excellent heat transfer performance, acceptable toxicity, zero or near-zero ODP and lubricant compatibility, including miscibility with POE and / or PVE lubricants within the operating temperature and concentration range for use in medium and low temperature refrigeration systems, cascade refrigeration systems, transport refrigeration systems, and heat pumps (including residential air-water heat pump systems), and that it remains non-flammable during use. This desired advantage can be achieved by the refrigerants of the present invention.

[0143] Applicants have discovered that the refrigerant compositions of the present invention (including each of Refrigerants 1 to 10) are capable of achieving a difficult to achieve combination of properties, including an exceptionally low GWP. Thus, the compositions of the present invention have a GWP of 150 or less.

[0144] In addition, the refrigerant composition of the present invention (including each of Refrigerants 1 to 10) has an ODP of zero or close to zero. Therefore, the composition of the present invention has an ODP of not more than 0.02, and more preferably zero.

[0145] In addition, the refrigerant compositions of the present invention, including each of Refrigerants 1 to 10, show acceptable toxicity and preferably have an OEL greater than about 400. As will be appreciated by those skilled in the art, a non-flammable refrigerant having an OEL greater than about 400 is advantageous because it results in the refrigerant being classified as the desired Class A of ASHRAE Standard 34.

[0146] Preferred refrigerant compositions of the present invention exhibit acceptable toxicity and non-flammability and are therefore Class A1 refrigerants according to ASHRAE Standard 34. Applicants have discovered that heat transfer compositions of the present invention (including heat transfer compositions comprising each of Refrigerants 1 to 10 as described herein) can provide exceptionally advantageous and unexpected combinations of properties, including: good heat transfer performance, chemical stability under use conditions, acceptable toxicity, non-flammability, zero or near zero ozone depletion potential ("ODP"), and lubricant compatibility, including miscibility with POE and / or PVE lubricants over the operating temperature and concentration ranges used in medium and low temperature refrigeration systems, cascade refrigeration systems, transport refrigeration systems, and heat pumps (including residential air-to-water heat pump systems).

[0147] The heat transfer composition can consist essentially of any of the refrigerants of the present invention, including each of Refrigerants 1 through 10.

[0148] The refrigerant of the present invention may be provided in the form of a heat transfer composition. Thus, the heat transfer composition of the present invention comprises the refrigerant of the present invention, including any of the preferred refrigerant compositions disclosed herein, and in particular each of refrigerants 1 to 10. Preferably, the present invention relates to a heat transfer composition comprising a refrigerant (including each of refrigerants 1 to 10) in an amount of at least about 80% by weight of the heat transfer composition, or at least about 90% by weight of the heat transfer composition, or at least about 97% by weight of the heat transfer composition, or at least about 99% by weight of the heat transfer composition. The heat transfer composition may consist essentially of or consist of the refrigerant.

[0149] The heat transfer composition of the present invention may be composed of any refrigerant of the present invention (including each of Refrigerants 1 to 10).

[0150] The heat transfer composition of the present invention may include other components for the purpose of enhancing or providing specific functions to the composition. In addition to the refrigerants of the present invention including each of refrigerants 1 to 10, such other components may include one or more of lubricants, passivators, flame retardants, dyes, solubilizers, compatibilizers, stabilizers, antioxidants, corrosion inhibitors, extreme pressure additives and anti-wear additives, as well as other compounds and / or components that adjust the specific properties of the heat transfer composition, and the presence of all such compounds and components is within the broad scope of the present invention.

[0151] Lubricants

[0152] The heat transfer composition of the present invention may include a refrigerant as described herein (including each of Refrigerants 1 to 10) and a lubricant. The heat transfer composition as described in this paragraph is sometimes referred to as Heat Transfer Composition 1 for convenience.

[0153] The heat transfer composition of the present invention may also include a refrigerant as described herein (including each of Refrigerants 1 to 10) and a polyol ester (POE) lubricant. The heat transfer composition as described in this paragraph is sometimes referred to as Heat Transfer Composition 2 for convenience.

[0154] The heat transfer composition of the present invention may also include a refrigerant as described herein (including each of Refrigerants 1 to 10) and a polyvinyl ether (PVE) lubricant. The heat transfer composition as described in this paragraph is sometimes referred to as Heat Transfer Composition 3 for convenience.

[0155] The heat transfer composition of the present invention may also include a refrigerant as described herein (including each of Refrigerants 1 to 10) and a polyol alkylene glycol (PAG) lubricant. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 4 for convenience.

[0156] The applicant has discovered that the heat transfer compositions of the present invention, including each of heat transfer compositions 1 to 10, can provide exceptionally advantageous properties, in addition to the advantageous properties with respect to refrigerants identified herein, including excellent refrigerant / lubricant compatibility, including miscibility with POE and / or PVE and / or PAG lubricants over the operating temperature and concentration ranges used in stationary air conditioning systems (including residential air conditioning, commercial air conditioning, VRF air conditioning), chillers (including air-cooled chillers), heat pump systems (including residential air-to-water heat pump systems), and commercial refrigeration (including medium temperature refrigeration and low temperature refrigeration).

[0157] A lubricant consisting essentially of POE having a viscosity at 40°C of about 30 to about 70 as measured according to ASTM D445 is referred to herein as Lubricant 1.

[0158] Commercially available POEs preferred for use in the heat transfer compositions of the present invention include neopentyl glycol dipelargonate, which is available as Emery 2917 (registered trademark) and Hatcol 2370 (registered trademark), and pentaerythritol derivatives, including those sold by CPI Fluid Engineering under the trade names Emkarate RL32-3MAF and Emkarate RL68H. Emkarate RL32-3MAF and Emkarate RL68H are preferred POE lubricants having the properties identified below:

[0159]

[0160] A preferred heat transfer composition comprises a refrigerant of the present invention (including each of Refrigerants 1 to 10) and Lubricant 1. The heat transfer composition as described in this paragraph is sometimes referred to as Heat Transfer Composition 5 for convenience.

[0161] A lubricant consisting essentially of a POE having a viscosity of about 30 to about 70 based on the weight of the heat transfer composition as measured at 40°C according to ASTM D445 is referred to herein as Lubricant 2.

[0162] Commercially available polyethylene ethers having a viscosity of about 30 to about 70 at 40°C as measured according to ASTM D445 that are preferred for use in the heat transfer compositions of the present invention include those lubricants sold under the trade names FVC32D and FVC68D available from Idemitsu.

[0163] The lubricant of the present invention may generally include a PVE lubricant. In a preferred embodiment, the PVE lubricant is such as a PVE according to the following formula II:

[0164]

[0165] Wherein R2 and R3 are each independently a C1-C10 hydrocarbon, preferably a C2-C8 hydrocarbon, and R1 and R4 are each independently an alkyl, an alkanediol, or a polyoxyalkylene glycol unit, and n and m are preferably selected according to the needs of those skilled in the art to obtain a lubricant having the desired properties, and the preferred n and m are selected to obtain a lubricant having a viscosity of about 30 cSt to about 70 cSt at 40° C. measured according to ASTM D445. The PVE lubricant described immediately above is referred to as Lubricant 3 for convenience. Commercially available polyvinyl ethers include those sold by Idemitsu under the trade names FVC32D and FVC68D.

[0166] A preferred heat transfer composition comprises a refrigerant of the present invention (including each of Refrigerants 1 to 10) and Lubricant 2. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 6A for convenience.

[0167] A preferred heat transfer composition comprises a refrigerant of the present invention (including each of Refrigerants 1 to 10) and Lubricant 3. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 6B for convenience.

[0168] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1 to 6, wherein the lubricant is present in the heat transfer composition in an amount from about 0.1% to about 5% by weight of the heat transfer composition. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 7 for convenience.

[0169] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1 to 6, wherein the lubricant is present in the heat transfer composition in an amount of about 0.1% to about 2% by weight of the heat transfer composition. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 8 for convenience.

[0170] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1 to 6, wherein the lubricant is present in the heat transfer composition in an amount from about 0.1% to about 1% by weight of the heat transfer composition. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 9 for convenience.

[0171] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1 to 6, wherein the lubricant is present in the heat transfer composition in an amount from about 0.1% to about 0.5% by weight of the heat transfer composition. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 10 for convenience.

[0172] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1 to 11, wherein the lubricant is present in the heat transfer composition in an amount of about 0.2% to about 0.5% by weight of the heat transfer composition. The heat transfer composition as described in this paragraph is sometimes referred to as heat transfer composition 11 for convenience.

[0173] Those skilled in the art may also, in view of the teachings contained herein, include other additives not mentioned herein without departing from the novel and essential characteristics of the present invention.

[0174] Combinations of surfactants and solubilizers may also be added to the compositions of the present invention to aid oil solubility as disclosed in US Pat. No. 6,516,837, the disclosure of which is incorporated by reference in its entirety.

[0175] Method, use and system

[0176] system

[0177] The present invention includes all types of heat transfer systems that include the refrigerant of the present invention (including each of Refrigerants 1 to 10) and / or include the heat transfer composition of the present invention (including each of Heat Transfer Compositions 1 to 11). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 1 for convenience.

[0178] The present invention also includes, and provides certain advantages associated with, a low temperature refrigeration system comprising a refrigerant of the present invention (including each of Refrigerants 1 to 10) and / or comprising a heat transfer composition of the present invention (including each of Heat Transfer Compositions 1 to 11). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 2 for convenience.

[0179] The present invention also includes, and provides certain advantages associated with, medium temperature refrigeration systems that include a refrigerant of the present invention (including each of Refrigerants 1 to 10) and / or include a heat transfer composition of the present invention (including each of Heat Transfer Compositions 1 to 11). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 3 for convenience.

[0180] The present invention also includes, and provides particular advantages associated with, extreme temperature air conditioning systems that include a refrigerant of the present invention (including each of Refrigerants 1 to 10) and / or include a heat transfer composition of the present invention (including each of Heat Transfer Compositions 1 to 11), and / or operate according to Heat Transfer Methods 1 to 3. A heat transfer system as described in this paragraph is sometimes referred to as Heat Transfer System 4 for convenience.

[0181] The present invention also includes, and provides particular advantages associated with, a high temperature heat pump system comprising a refrigerant of the present invention (including each of refrigerants 1 to 10) and / or comprising a heat transfer composition of the present invention (including each of heat transfer compositions 1 to 11), and / or operating according to heat transfer methods 1 to 3. The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 5A for convenience.

[0182] The present invention also includes, and provides particular advantages associated with, medium temperature refrigeration systems that include a refrigerant of the present invention (including each of Refrigerants 1 to 10) and / or include a heat transfer composition of the present invention (including each of Heat Transfer Compositions 1 to 11). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 5B for convenience.

[0183] The present invention also includes, and provides certain advantages associated with, a cascade refrigeration system comprising a refrigerant of the present invention (including each of refrigerants 1 to 10) and / or comprising a heat transfer composition of the present invention (including each of heat transfer compositions 1 to 11). A heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 6 for convenience.

[0184] The present invention also provides a basic cascade refrigeration system, which comprises:

[0185] (a) Primary refrigeration circuit, including:

[0186] Low-grade refrigerants with a GWP of about 150 or less; and

[0187] compressor;

[0188] (b) an inter-circuit heat exchanger in which the low-grade refrigerant is condensed; and

[0189] (c) A high-stage refrigeration circuit including a high-stage refrigerant which evaporates in the inter-circuit heat exchanger by absorbing heat from the refrigerant in the low-stage refrigeration circuit.

[0190] The following table defines a series of cascade refrigeration systems of the present invention, which include the elements of this paragraph and additionally require the elements or restrictions specified in the following table, wherein each such system is defined as a cascade system (CS) of the present invention by the CS number / letter in column 1 of the following table, it being understood that all values ​​are understood to be preceded by the word "about" unless otherwise indicated in the table. In the following table, it is also understood that unless a "refrigerant component" is specifically indicated in the table as "consisting essentially of" or "consisting of", the refrigerant includes the indicated refrigerant component. Similarly, it is also understood that unless a "refrigerant" under the heading "lower requirements" is specifically indicated in the table as "consisting essentially of" or "consisting of", the lower level includes the indicated refrigerant. The designation "NR" should be understood to mean that the component or characteristic is not required (but may be present), and the designation "NL" means that the characteristic of the feature is not limited by the definition in the table.

[0191] Cascade system

[0192]

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 in the above table, wherein the low-grade refrigerant condenses in the inter-circuit heat exchanger at a temperature in the range of about -5°C to about -15°C. For convenience, the system according to this paragraph is sometimes referred to herein as cascade refrigeration system 13.

[0200] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 in the above table, wherein the high-grade refrigerant evaporates in the inter-circuit heat exchanger at a temperature in the range of about -5°C to about -15°C. For convenience, the system according to this paragraph is sometimes referred to herein as a cascade refrigeration system 14.

[0201] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 and 14 in the above table, wherein the low-stage refrigeration circuit includes multiple low-stage refrigeration circuits. For convenience, the system according to this paragraph is sometimes referred to herein as a cascade refrigeration system 15.

[0202] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 to 15 in the above table, wherein the low-stage refrigeration circuit is located in an area open to the public. For convenience, the system according to this paragraph is sometimes referred to herein as a cascade refrigeration system 16.

[0203] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 to 16 in the above table, wherein the low-stage refrigeration circuit includes a plurality of self-contained low-stage refrigeration circuits, wherein at least two of such low-stage circuits are contained in separate modular refrigeration units, and each of the modular refrigeration units is located in a first area open to the public. For convenience, the system according to this paragraph is sometimes referred to herein as system 17.

[0204] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 to 17 in the above table, wherein the compressor in each of the low stages has a horsepower rating of about 2 horsepower or less. For convenience, the system according to this paragraph is sometimes referred to herein as cascade refrigeration system 18.

[0205] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 to 18 in the above table, wherein the low stage includes a low temperature refrigeration circuit. For convenience, the system according to this paragraph is sometimes referred to herein as a cascade refrigeration system 19.

[0206] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 to 19 in the above table, wherein the high stage includes a medium temperature refrigeration circuit. For convenience, the system according to this paragraph is sometimes referred to herein as a cascade refrigeration system 20.

[0207] The present invention includes a cascade refrigeration system including each of cascade systems 1 to 12 and cascade systems 13 to 20 in the above table, wherein the system comprises a commercial refrigeration system. For convenience, the system according to this paragraph is sometimes referred to herein as a cascade refrigeration system 21.

[0208] The present invention also includes a cooler (including an air-cooled cooler), and provides specific advantages associated therewith, which cooler includes the refrigerant of the present invention (including each of refrigerants 1 to 10) and / or includes the heat transfer composition of the present invention (including each of heat transfer compositions 1 to 11) and / or includes the cascade refrigeration system of the present invention (including each of cascade refrigeration systems 1 to 21). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 7 for convenience.

[0209] The present invention also includes a heat pump system, and provides specific advantages associated therewith, which heat pump system includes the refrigerant of the present invention (including each of refrigerants 1 to 10) and / or includes the heat transfer composition of the present invention (including each of heat transfer compositions 1 to 11) and / or includes the cascade refrigeration system of the present invention (including each of cascade refrigeration systems 1 to 21). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 8 for convenience.

[0210] The present invention also includes commercial refrigeration (including low temperature commercial refrigeration and medium temperature commercial refrigeration), and provides specific advantages related thereto, which commercial refrigeration includes the refrigerant of the present invention (including each of refrigerants 1 to 10) and / or includes the heat transfer composition of the present invention (including each of heat transfer compositions 1 to 11) and / or includes the cascade refrigeration system of the present invention (including each of cascade refrigeration systems 1 to 21). The heat transfer system as described in this paragraph is sometimes referred to as heat transfer system 9 for convenience.

[0211] For the heat transfer system of the present invention including a compressor and a lubricant for the compressor in the system, the system may include a load of a refrigerant (including each of refrigerants 1 to 10) and a lubricant (including POE and PVE lubricants) of the present invention such that the lubricant load in the system is from about 5 wt % to 60 wt %, or from about 10 wt % to about 60 wt %, or from about 20 wt % to about 50 wt %, or from about 20 wt % to about 40 wt %, or from about 20 wt % to about 30 wt %, or from about 30 wt % to about 50 wt %, or from about 30 wt % to about 40 wt %. As used herein, the term "lubricant load" refers to the total weight of the lubricant contained in the system as a percentage of the total amount of lubricant and refrigerant contained in the system. Such a system may also include a lubricant load of about 5 wt % to about 10 wt %, or about 8 wt % of the heat transfer composition.

[0212] In a specific aspect, as shown below, in a low temperature refrigeration system, the heat transfer composition of the present invention comprises any one of refrigerants 1 to 10 and a lubricant:

[0213] refrigerant Lubricants Refrigeration system Refrigerant 1 POE or PVE Low temperature refrigeration Refrigerant 2 POE or PVE Low temperature refrigeration Refrigerant 3 POE or PVE Low temperature refrigeration Refrigerant 4 POE or PVE Low temperature refrigeration Refrigerant 5 POE or PVE Low temperature refrigeration Refrigerant 6 POE or PVE Low temperature refrigeration Refrigerant 7 POE or PVE Low temperature refrigeration Refrigerant 8 POE or PVE Low temperature refrigeration Refrigerant 9 POE or PVE Low temperature refrigeration Refrigerant 10 POE or PVE Low temperature refrigeration

[0214] As shown below, in a medium temperature refrigeration system, the heat transfer composition includes any one of refrigerants 1 to 10 and a lubricant

[0215] refrigerant Lubricants Refrigeration system Refrigerant 1 POE or PVE Medium temperature refrigeration Refrigerant 2 POE or PVE Medium temperature refrigeration Refrigerant 3 POE or PVE Medium temperature refrigeration Refrigerant 4 POE or PVE Medium temperature refrigeration Refrigerant 5 POE or PVE Medium temperature refrigeration Refrigerant 6 POE or PVE Medium temperature refrigeration Refrigerant 7 POE or PVE Medium temperature refrigeration Refrigerant 8 POE or PVE Medium temperature refrigeration Refrigerant 9 POE or PVE Medium temperature refrigeration Refrigerant 10 POE or PVE Medium temperature refrigeration Refrigerant 11 POE or PVE Medium temperature refrigeration

[0216] As shown below, in a retail food refrigeration system, the heat transfer composition includes any one of refrigerants 1 to 10 and a lubricant:

[0217] refrigerant Lubricants Refrigeration system Refrigerant 1 POE or PVE Retail Food Refrigeration Refrigerant 2 POE or PVE Retail Food Refrigeration Refrigerant 3 POE or PVE Retail Food Refrigeration Refrigerant 4 POE or PVE Retail Food Refrigeration Refrigerant 5 POE or PVE Retail Food Refrigeration Refrigerant 6 POE or PVE Retail Food Refrigeration Refrigerant 7 POE or PVE Retail Food Refrigeration Refrigerant 8 POE or PVE Retail Food Refrigeration Refrigerant 9 POE or PVE Retail Food Refrigeration Refrigerant 10 POE or PVE Retail Food Refrigeration

[0218] As shown below, in a transport refrigeration system, the heat transfer composition includes any one of refrigerants 1 to 10 and a lubricant:

[0219] refrigerant Lubricants Refrigeration system Refrigerant 1 POE or PVE Transport Refrigeration Refrigerant 2 POE or PVE Transport Refrigeration Refrigerant 3 POE or PVE Transport Refrigeration Refrigerant 4 POE or PVE Transport Refrigeration Refrigerant 5 POE or PVE Transport Refrigeration Refrigerant 6 POE or PVE Transport Refrigeration Refrigerant 7 POE or PVE Transport Refrigeration Refrigerant 8 POE or PVE Transport Refrigeration Refrigerant 9 POE or PVE Transport Refrigeration Refrigerant 10 POE or PVE Transport Refrigeration

[0220] Exemplary Heat Transfer Systems

[0221] As described in detail below, the preferred system of the present invention includes a compressor, a condenser, an expansion device, and an evaporator, all of which are connected in fluid communication using pipes, valves, and a control system so that the relevant components of the refrigerant and heat transfer composition can flow through the system in a known manner to complete the refrigeration cycle. An exemplary schematic diagram of such a basic system is shown in FIG. Figure 1 Specifically, Figure 1The system schematically illustrated in shows a compressor 10 that provides compressed refrigerant vapor to a condenser 20. The compressed refrigerant vapor is condensed to produce liquid refrigerant, which is then directed to an expansion device 40 that produces refrigerant at a reduced temperature pressure, which is then, in turn, provided to an evaporator 50. In the evaporator 50, the liquid refrigerant absorbs heat from the body or fluid being cooled, thereby producing refrigerant vapor, which is then provided to the suction line of the compressor.

[0222] Figure 2 The refrigeration system shown in the above is combined with Figure 1 The same as described above, except that it includes a vapor injection system that includes a heat exchanger 30 and a bypass expansion valve 25. The bypass expansion device 25 diverts a portion of the refrigerant flow at the outlet of the condenser through the device, thereby providing liquid refrigerant to the heat exchanger 30 at a reduced pressure and, therefore, at a lower temperature. The relatively cold liquid refrigerant then exchanges heat with the remaining relatively high temperature liquid from the condenser. This operation produces subcooled liquid to the main expansion device 40 and the evaporator 50, and returns relatively cold refrigerant vapor to the compressor 10. In this way, the injection of cooled refrigerant vapor into the suction side of the compressor is used to keep the compressor discharge temperature within acceptable limits, which can be particularly advantageous in low temperature systems utilizing high compression ratios.

[0223] Figure 3 The refrigeration system shown in the above is combined with Figure 1 The same as described above, except that it includes a liquid injection system that includes a bypass valve 26. The bypass valve 26 diverts a portion of the liquid refrigerant leaving the condenser to the compressor, preferably to a liquid injection port in the compressor 10. In this way, the injection of liquid refrigerant into the suction side of the compressor serves to maintain the compressor discharge temperature within acceptable limits, which can be particularly advantageous in low temperature systems utilizing high compression ratios.

[0224] Figure 4 The refrigeration system shown in the above is combined with Figure 1 Same as described above, except that it includes a liquid line / suction line heat exchanger 35. Valve 25 diverts a portion, and optionally all, of the refrigerant flow from the condenser outlet to the liquid line / suction line heat exchanger 35, wherein heat is transferred from the liquid refrigerant to the refrigerant vapor exiting the evaporator 50, and the further cooled liquid refrigerant exiting the heat exchanger 35 is directed to the expansion device 40 and the evaporator 50.

[0225] Figure 5 The refrigeration system shown in the above is combined with Figure 1The same as described above, except that it includes an oil separator 60 connected to the outlet of the compressor 10. As is known to those skilled in the art, a certain amount of compressor lubricant is usually carried over into the compressor discharge refrigerant vapor, and an oil separator is included to provide a means for separating the lubricant liquid from the refrigerant vapor, and the resulting refrigerant vapor with reduced lubricating oil content is passed to the condenser inlet, and then the liquid lubricant is returned to a lubricant reservoir used in lubricated compressors, such as a lubricant receiver. In a preferred embodiment, the oil separator includes a chelating material as described herein, preferably in the form of a filter or solid core.

[0226] Those skilled in the art will understand that Figures 2 to 5 The different equipment / configuration options shown individually in each of the embodiments may be combined and used together, which is considered to be advantageous for any application, including in cascade refrigeration systems, the preferred embodiments of which are described above in conjunction with Fig. 6A and Figure 6B And combined with the following Figure 7 The description is given to FIG. 9 .

[0227] Cascade system

[0228] The present invention also includes a cascade refrigeration system comprising each of the cascade systems 1 to 21, wherein the heat exchanger (iii) is a heat exchanger in which the high-stage refrigerant evaporates in the heat exchanger by absorbing heat from the low-stage.

[0229] The present invention also includes a cascade refrigeration system, which includes each of cascade systems 1 to 21, the cascade refrigeration system comprising: a plurality of low temperature refrigeration circuits, each low temperature refrigeration circuit including a flammable low temperature refrigerant, the flammable low temperature refrigerant containing at least about 50% by weight, or at least about 75% by weight, or at least 95% by weight, or at least 99% by weight of HFO-1234yf, R454C, R455A, propane, or a combination of these. As used herein, reference to a numbering system or numbering system group defined herein means each such numbering system, including each system with a number within the group, including any suffix numbering system. For example, a reference to cascade system 1 includes a reference to each of cascade systems 1A, 1B, and 1C.

[0230] The present invention also includes a cascade refrigeration system, which includes each of the cascade systems 1 to 21, the cascade refrigeration system comprising: a plurality of low-temperature refrigeration circuits, each low-temperature refrigeration circuit comprising a flammable low-temperature refrigerant, the flammable low-temperature refrigerant containing at least about 75 weight %, or at least 95 weight %, or at least 99 weight % of HFO-1234yf, wherein the heat exchanger is a heat exchanger in which the intermediate-temperature refrigerant evaporates by absorbing heat from the low-temperature refrigerant.

[0231] As used herein, the term "low temperature refrigeration unit" means an at least partially enclosed or enclosable structure capable of providing cooling within at least a portion of the structure and structurally distinct from any structure that encloses or houses a high-stage refrigeration circuit. In accordance with and consistent with such meaning, the preferred low-stage refrigeration circuit and low-temperature refrigeration circuit, when housed within such a first (preferably low temperature) refrigeration unit in accordance with the meanings described herein, are sometimes referred to herein as "self-contained".

[0232] In a preferred embodiment, each low-stage refrigeration unit (including such units corresponding to the low stage in each of the cascade systems 1 to 21) may be located in a first area. The first area may be a store area. This means that each first refrigeration circuit (preferably a low-temperature refrigeration circuit) may also be located in a first area, such as a store or supermarket floor accessible to the public.

[0233] Each refrigeration unit included in each of the cascade systems 1 to 11 may include a space to be cooled and / or an object contained within the space, and preferably the space is within the refrigeration unit. Each evaporator may be positioned to cool its corresponding space / object, preferably by cooling the air within the space to be cooled.

[0234] As described above, the advanced refrigeration circuit of the present invention (including the advanced refrigeration circuit in each of the cascade systems 1 to 11) can have its components extending between the low-stage refrigeration unit (preferably the low-temperature refrigeration unit) and the second area. The second area can be, for example, a machine room that houses most of the components of the advanced refrigeration circuit.

[0235] The advanced refrigeration circuit of the present invention included in each of the cascade systems 1 to 21 can be extended to the second and third areas. The third area can be an area outside the building or buildings where the first refrigeration unit and the second area are located. This enables ambient cooling to be utilized.

[0236] Unless otherwise indicated herein, for a particular embodiment, the refrigerant in each low-stage refrigeration circuit may be different or the same as the other refrigerants in the low-stage refrigeration circuit, and the refrigerant in each low-stage refrigeration circuit may also be the same as or different from the refrigerant in the high-stage refrigeration circuit.

[0237] The advanced refrigeration loop may be quite long and may extend between different areas of a building: for example, between a store floor (where the refrigeration units may be deployed) and a machine room. Therefore, having a flammable refrigerant in the advanced refrigeration loop may be unsafe because both the risk of leakage and the severity of a potential leakage are increased because in such embodiments the advanced refrigeration loop spans a larger area, thus exposing more people and / or structures to the risk of fire.

[0238] Each low-stage refrigeration circuit included in each of the cascade systems 1 to 21 may include at least one fluid expansion device. The at least one fluid expansion device may be a capillary tube or a fixed throttle. This is achieved by the conditions imposed on each first refrigeration circuit by its corresponding refrigeration unit being relatively constant. This means that simpler flow control devices, such as capillary tubes and throttle tubes, can and preferably are advantageously used in the first refrigeration circuit.

[0239] The high-level refrigeration circuit included in each of the cascade systems 1 to 21 may include a second evaporator. The second evaporator may be connected in parallel with the circuit interface location.

[0240] One embodiment of the cascade refrigeration system according to the present invention is Figure 7 It is schematically shown in FIG. 1 and described in detail below.

[0241] Figure 7 A cascade refrigeration system 200 is shown. More specifically, Figure 7 A refrigeration system 200 having three low-level refrigeration circuits 220a, 220b, and 220c is shown. Each of the low-level refrigeration circuits 220a, 220b, and 220c has an evaporator 223, a compressor 221, a heat exchanger 230, and an expansion valve 222. Although each of the compressors, evaporators, and heat exchangers in the circuit is shown by a single icon, it should be understood that the compressor, evaporator, heat exchanger, expansion valve, etc. may each include a plurality of such units. In each circuit 220a, 220b, and 220c, the evaporator 223, the compressor 221, the heat exchanger 230, and the expansion valve 222 are connected in series with each other in the listed order. Each of the low-level refrigeration circuits 220a, 220b, and 220c is included in an independent corresponding refrigeration unit (not shown). In this example, each of the three refrigeration units is preferably a refrigerator unit, and the refrigerator unit accommodates a corresponding low-temperature refrigeration circuit. In this way, each refrigeration unit includes a self-contained and dedicated low-temperature refrigeration circuit. The refrigeration unit (not shown) and thus the low-temperature refrigeration circuit 220a, 220b, 220c may be arranged on a sales floor 242 of, for example, a supermarket.

[0242] In this example, the refrigerant in each of the low-stage refrigeration circuits 220a, 220b, 220c is a low GWP refrigerant such as CO2, propane, HFO-1234yf, R454C, R455A, or a combination of two or more of these. As will be appreciated by those skilled in the art, the refrigerant in each of the low-stage circuits 220a, 220b, 220c may be the same or different from the refrigerant in each of the other low-stage refrigeration circuits 220a, 220b, 220c, but in a preferred embodiment, each of the plurality of low-stage circuits comprises CO2, propane, HFO-1234yf, R454C, R455A, or a combination of two or more of these.

[0243] The refrigeration system 200 also has an advanced refrigeration circuit 210. The advanced refrigeration circuit 210 has a compressor 211, a condenser 213, and a fluid receiver 214. The compressor 211, the condenser 213, and the fluid receiver 214 are connected in series in a given order. Although each of the compressor, the condenser, the fluid receiver, etc. in the advanced circuit is shown by a single icon, it should be understood that the compressor, the evaporator, the heat exchanger, the expansion valve, etc. may each include a plurality of such units. The advanced refrigeration circuit 210 also has four parallel-connected branches: three medium-temperature cooling branches 217a, 217b, and 217c, which are not in heat transfer communication with the low-stage refrigeration circuit; and a low-stage cooling branch 216. The four parallel-connected branches 217a, 217b, 217c, and 216 are connected between the fluid receiver 214 and the compressor 211. Each of the medium temperature cooling branches 217a, 217b and 217c has an expansion valve 218a, 218b and 218c and an evaporator 219a, 219b and 219c, respectively. The expansion valve 218 and the evaporator 219 are connected in series and in a given order between the fluid receiver 214 and the condenser 211. The high-grade circuit 220 including the low-temperature cooling branch 216 in the preferred embodiment has an expansion valve 212 and an interface in the form of inlet and outlet pipes, conduits, valves, etc. (collectively referred to as 260a, 260b and 260c, respectively), which brings the high-grade refrigerant liquid to each of the inter-circuit heat exchangers 230a, 230b, 230c and takes away the high-grade refrigerant vapor from each inter-circuit heat exchanger, as shown in the preferred embodiment, these inter-circuit heat exchangers are located in the refrigeration unit 220. The low temperature cooling branch 216 interfaces with each of the inter-circuit heat exchangers 230a, 230b, 230c at a respective circuit interface 231a, 231b, 231c. Each circuit interface 231a, 231b, 231c is arranged in a series-parallel combination with each other circuit interface 231a, 231b, 231c.

[0244] The high-grade refrigeration circuit 210 has components extending between the sales area 242, the machine room 241, and the ceiling 140. The cooling branch 216 and the medium-temperature branches 218a, 218b, 218c of the medium-temperature refrigeration circuit 210 are preferably located on the sales area 242. The compressor 211 and the fluid receiver 214 are preferably located in the machine room 241. The condenser 213 is preferably located where it can be easily exposed to environmental conditions, such as on the ceiling 240.

[0245] In this example, the refrigerant in the advanced refrigeration loop 210 comprises, consists essentially of, or consists of a refrigerant containing at least about 74 weight percent HFO-1234ze and having a class 1A or A2L flammability. The present invention includes a cascade system wherein the refrigerant in the advanced refrigeration loop 210 comprises, consists essentially of, or consists of HFO-1234ze(E), HDR165, and / or HDR166. Further advantageously, the blend has a low GWP, making it an environmentally friendly solution, and has excellent heat transfer performance characteristics, as described below in its embodiments.

[0246] like Figure 7 The use of the preferred embodiment shown can be summarized as follows:

[0247] Each of the low-stage refrigeration circuits 220a, 220b, 220c absorbs heat via its evaporator 223 to provide low-temperature cooling to a space to be cooled (not shown);

[0248] The high-level refrigeration circuit 210 is connected to the inter-circuit heat exchangers 230a, 230b,

[0249] Each of 230c absorbs heat to cool and condense the heat from the low-level loop 220a,

[0250] low-stage refrigerant vapor of a corresponding compressor in each of 220b, 220c;

[0251] The high-level refrigeration circuit 210 absorbs heat at each of the evaporators 219 to provide medium-temperature cooling to a space to be cooled (not shown); and

[0252] • Heat is removed from the refrigerant in the high-stage refrigeration loop 210 in the air-cooled chiller 213 .

[0253] Available Figure 7The arrangement of the invention of the type shown achieves a number of advantageous results, particularly each refrigeration circuit 230 in the respective refrigeration unit being self-contained. For example, installation and removal of the refrigeration units and the overall cascade refrigeration system 200 is simplified. This is because the refrigeration unit with its built-in self-contained refrigeration circuit 220a, 220b, 220c can be easily connected or disconnected from the advanced refrigeration circuit 210 without having to change the refrigeration circuit 220, 220b, 220c. In other words, the refrigeration unit can be simply "plugged" into or unplugged from the advanced refrigeration circuit 210.

[0254] Another advantage is that each refrigeration unit (including its respective first refrigeration circuit 220a, 220b, 220c) can be factory tested to default values ​​prior to installation in the live refrigeration system 200. This reduces the likelihood of failures (which may include potentially harmful refrigerant leaks). Thus, reduced leakage rates can be achieved.

[0255] Another advantage of the preferred embodiment is the provision of an inter-circuit heat exchanger, which in the system of the present invention comprises each of the cascade systems 1 to 21, thereby improving the heat transfer between the low stage and the high stage. Thus, the efficiency of the overall refrigeration system is improved.

[0256] In a preferred embodiment, including each of the cascade systems 1 to 21, the present invention also includes a cascade refrigeration system, which includes: a plurality of low-temperature refrigeration circuits, each low-temperature refrigeration circuit including a low-temperature refrigerant having a GWP of about 150 or less and containing at least about 75% by weight of R1234yf (specifically including R-454C and / or R455A); a compressor having a work output of about 3.5 kW or less; an inter-circuit heat exchanger in which the low-temperature refrigerant is heated at a temperature of about -5°C to about -15°C. condensing within a temperature range; and a medium-temperature refrigeration circuit, which includes a medium-temperature refrigerant, wherein the medium-temperature refrigerant contains at least about 74 weight % of HFO-1234ze(E) (specifically including HDR165 and / or HDR166), is essentially composed of it or consists of it; and an evaporator, in which the medium-temperature refrigerant is evaporated at a temperature lower than the condensing temperature of the low-temperature refrigerant and in the range of about -5°C to about -15°C, wherein the medium-temperature refrigerant evaporates in the heat exchanger by absorbing heat from the low-temperature refrigerant.

[0257] In a preferred embodiment, including each of the cascade systems 1 to 21, the present invention also includes a cascade refrigeration system, which includes: a plurality of low-temperature refrigeration circuits, each low-temperature refrigeration circuit including a low-temperature refrigerant having a GWP of about 150 or less and containing at least about 75% by weight of R1234yf (specifically including R-454C and R-455A); and a compressor having a compressor rating of 2 horsepower or less; an inter-circuit heat exchanger, in which the low-temperature refrigerant condenses at a temperature range of about -5°C to about -15°C; and an intermediate-temperature refrigeration circuit, which includes an intermediate-temperature refrigerant, wherein the intermediate-temperature refrigerant contains at least about 74% by weight of HFO-1234ze(E) (specifically including HDR165 and / or HDR-166), is essentially composed of it or consists of it; and an evaporator, in which the intermediate-temperature refrigerant evaporates at a temperature lower than the condensation temperature of the low-temperature refrigerant and in the range of about -5°C to about -15°C, wherein the intermediate-temperature refrigerant evaporates in the heat exchanger by absorbing heat from the low-temperature refrigerant.

[0258] Cascade Refrigeration System - Alternative Solution

[0259] A person skilled in the art will understand from the teachings contained herein that according to the present invention, including each of the cascade systems 1 to 21, there may be any number of low-stage refrigeration circuits 220. Specifically, there may be as many low-stage circuits 220 as there are refrigeration units to be cooled. Thus, the high-stage refrigeration circuit 210 may interface with any number of low-stage refrigeration circuits 220, and vice versa.

[0260] It will be clear to those skilled in the art based on the teachings contained herein that any number and arrangement of high-level circuit loop branches 217 and evaporators 218 may be present according to the present invention, including each of the cascade systems 1 to 21. In an alternative arrangement according to the present invention, including each of the cascade systems 1 to 21, each low-level circuit 220 may be arranged completely in parallel with each other low-level circuit 220. An example of such an arrangement is shown in Figure 8 middle. Figure 8 A system 300 is shown in which each circuit junction location present in the inter-circuit heat exchangers 231a, 231b, 231c is arranged completely in parallel with each other circuit junction location. The components of the system 300 are otherwise similar to those of the system 200 (see Figure 7 3. Although system 300 is identical to system 200 and the components of system 300 function in substantially the same manner as system 200, it should be understood that the performance of the overall system as well as other important features of the overall system may be significantly affected by this change in arrangement.

[0261] Usefully, this means that a given portion of the refrigerant from the high-level circuit 210 passes through only one inter-circuit heat exchanger 230 before returning to the compressor 211. The arrangement therefore ensures that each of the heat exchangers 230 will receive high-level refrigerant at approximately the same temperature, as the arrangement prevents any heat exchanger from receiving a portion of the refrigerant that has been preheated by passing through an upstream heat exchanger, as would be the case with a series arrangement.

[0262] It will be apparent to those skilled in the art based on the teachings contained herein that many other arrangements of the circuit interface locations 231a, 231b, 231c relative to one and the advanced refrigeration circuits 210 can be achieved and are in fact conceivable according to the present invention, including each of the cascade systems 1 to 21.

[0263] It will be apparent to those skilled in the art from the teachings contained herein that the preferred modular design of the low-stage circuit of the preferred embodiments of the present invention (including each of the cascade systems 1 to 21) allows the use of non-flammable low-pressure refrigerants with relatively low GWP.

[0264] Suction line heat exchanger

[0265] Another possible change of any system (including each of the cascade systems 1 to 21) forming part of the present disclosure is that any number of self-contained refrigeration circuits may include a suction line heat exchanger (SLHX). More specifically, any of the low-stage refrigeration circuits 220a, 220b, 220c in the system 200 (including each of the cascade systems 1 to 21) may include a SLHX; and any of the low-stage refrigeration circuits 420a, 420b may include a SLHX.

[0266] Using SLX can reduce the temperature of the refrigerant entering the expansion valve 730. This additional subcooling after the expansion valve 730 process results in a lower inlet mass in the evaporator 740. This increases the enthalpy difference and therefore increases the capacity of the refrigerant to absorb heat in the evaporator 740 stage. Therefore, the performance of the evaporator 740 is improved.

[0267] In summary, to determine whether the introduction of SLHX results in an overall beneficial effect, the first and second effects of increasing evaporator capacity and increasing compressor power requirements need to be considered. In general, according to the present invention, including each of the cascade systems 1 to 21, and particularly such systems 200 and 300 herein, the use of SLHX results in an overall positive and unexpected beneficial effect.

[0268] method

[0269] Air conditioning method

[0270] The present invention also relates to an air conditioning system, which includes a refrigerant of the present invention (including each of refrigerants 1 to 10) or a heat transfer composition containing a refrigerant of the present invention (including each of heat transfer compositions 1 to 1). The present invention also provides a method of air conditioning using an air conditioning system, the method comprising the steps of: (a) evaporating a refrigerant composition of the present invention (including each of refrigerants 1 to 10) near a fluid or body to be cooled; and (b) condensing the refrigerant. The air can be conditioned directly or indirectly by the refrigerant of the present invention (including each of refrigerants 1 to 10). Examples of air conditioning systems include chillers, residential air conditioners, industrial air conditioners, commercial air conditioners, and mobile air conditioners, including air conditioners of road vehicles (such as cars, trucks, and buses), and air conditioners of boats and trains.

[0271] A preferred refrigeration system of the present invention comprises a chiller comprising the refrigerant of the present invention, specifically comprising each of Refrigerants 1 to 10 .

[0272] Preferred refrigeration systems of the present invention include residential air conditioning systems including the refrigerant of the present invention, specifically including each of Refrigerants 1-10.

[0273] Preferred refrigeration systems of the present invention include industrial air conditioning systems, which include the refrigerant of the present invention, specifically including each of Refrigerants 1 to 10.

[0274] Preferred refrigeration systems of the present invention include commercial air conditioning systems including the refrigerant of the present invention, specifically including each of Refrigerants 1 to 10.

[0275] Preferred refrigeration systems of the present invention include mobile air conditioning systems, which include the refrigerant of the present invention, specifically each of Refrigerants 1 to 10.

[0276] It should be understood that any of the above-mentioned refrigeration, air conditioning or heat pump systems using the refrigerant of the present invention (including each of Refrigerants 1 to 10) or the heat transfer composition containing the refrigerant of the present invention (including each of Heat Transfer Compositions 1 to 11) may include a suction line / liquid line heat exchanger (SL-LL HX).

[0277] Organic Rankine Cycle System

[0278] The refrigerant compositions of the present invention (including each of Refrigerants 1 to 10) or heat transfer compositions comprising the refrigerants of the present invention (including each of Heat Transfer Compositions 1-11) can be used in an organic Rankine cycle (ORC). In the context of the ORC, the refrigerants used in these systems can also be classified as "working fluids." It is known that the Rankine cycle system is a simple and robust device for converting thermal energy into mechanical shaft energy.

[0279] In industrial environments, flammable working fluids (such as toluene and pentane) may be used, especially when the industrial environment already has a large amount of combustibles on site in the process or storage. However, in situations where the risks associated with using flammable and / or toxic working fluids are unacceptable, such as power generation in populated areas or near buildings, non-flammable and / or non-toxic refrigerants must be used as working fluids. There is also a drive in industry to make these materials environmentally acceptable in terms of GWP.

[0280] A process for recovering waste heat in an organic Rankine cycle system involves pumping a liquid-phase working fluid through a heat exchanger (boiler) where an external (waste) heat source (such as a process stream) heats the working fluid, causing it to evaporate into a saturated or superheated vapor. The vapor is expanded through a turbine where the waste heat energy is converted into mechanical energy. Subsequently, the gas-phase working fluid is condensed into a liquid and pumped back into the boiler to repeat the regenerative cycle. Therefore, the present invention relates to the use of a refrigerant of the present invention (including each of refrigerants 1 to 10) or a heat transfer composition comprising a refrigerant of the present invention (including each of heat transfer compositions 1 to 11) in an organic Rankine cycle.

[0281] Thus, the present invention provides a method for converting thermal energy into mechanical energy in a Rankine cycle, the method comprising the steps of: i) evaporating a working fluid with a heat source and expanding the resulting vapor, or evaporating a working fluid with a heat source and expanding the resulting vapor, and then ii) cooling the working fluid with a heat sink to condense the vapor, wherein the working fluid is a refrigerant or a refrigerant of the present invention (including each of Refrigerants 1 to 11), or a heat transfer composition comprising a refrigerant of the present invention (including each of the heat transfer compositions). The mechanical work can be transmitted to an electrical device such as a generator to generate electricity.

[0282] The heat source can be provided by a thermal energy source selected from industrial waste heat, solar energy, geothermal hot water, low-pressure steam, distributed power generation equipment using fuel cells, internal combustion engines or prime movers. Preferably, the low-pressure steam is low-pressure geothermal steam or is provided by a power plant powered by fossil fuels.

[0283] It should be understood that the heat source temperature can vary widely, for example from about 90°C to >800°C, and can depend on many factors for certain combustion gases and some fuel cells, including geographic location, time of year, etc. The source temperature for systems based on sources such as wastewater or low pressure steam (from, for example, plastic manufacturing plants and / or from chemical or other industrial plants, refineries, etc.) and geothermal sources can be at or below about 100°C, and in some cases as low as about 90°C or even as low as about 80°C. The source temperature for gaseous heat sources (such as exhaust from combustion processes or from any heat source where subsequent processing to remove particulates and / or corrosive materials results in low temperatures) can also be at or below about 130°C, at or below about 120°C, at or below about 100°C, at or below about 100°C, and in some cases as low as about 90°C or even as low as about 80°C.

[0284] Electronics Cooling

[0285] The refrigerant compositions of the present invention (including any of Refrigerants 1 to 11) can be used in conjunction with systems and methods for cooling electronic devices, such as chip cooling, electronic board cooling, battery cooling (including batteries used in cars, trucks, buses and other electronic transportation vehicles), computer cooling, etc.

[0286] Example

[0287] In the following examples, refrigerant compositions according to the present invention are identified as compositions E1 to E7 in Table E below. Applicants have tested and evaluated each refrigerant, and found that they are non-flammable, that is, they are Class A1 refrigerants, and have also performed thermodynamic analysis on each of E1 to E7 to determine the ability to match the operating characteristics of R-134a in various refrigeration systems. For the characteristics of each binary and ternary component pair used in the refrigerant, the collected experimental data are used for analysis. In the experimental evaluation, the composition of each pair changes in a series of relative percentages, and the mixture parameters of each pair are regressed into experimentally obtained data. The known vapor / liquid equilibrium behavior data obtained from the U.S. National Institute of Science and Technology (NIST) reference fluid thermodynamics and transport properties database software (Refprop 9.1NIST standard database 23, from April 2016) are used for embodiments. Each blend has also been evaluated to determine its flammability classification as described above.

[0288] Table E1A: Refrigerants according to the invention subjected to performance tests

[0289]

[0290] As can be seen from the above Table E1A, each of the refrigerants E1 to E7 according to the present invention achieves a GWP value (AR5) lower than 150 while achieving A1-level flammability.

[0291] For comparative purposes, five refrigerant blends outside the scope of the refrigerants of the present invention were also analyzed to determine the GWP. Each refrigerant was based on a combination of HFO-1234ze (E), HFO-1224yd (Z) and HFC-134 (1,1,1,2-tetrafluoroethane), and the results of the analysis are provided in Table C below.

[0292] Table C: Comparative Refrigerants Subjected to Performance Testing

[0293]

[0294] In contrast to the refrigerants of the present invention, none of the refrigerants C1 to Cs can achieve a GWP of less than 150.

[0295] Examples 1A to 1D: Performance in a Medium Temperature Refrigeration System

[0296] The performance of refrigerants E1 to E7 was tested in a medium temperature refrigeration system without a suction line / liquid line heat exchanger (SL / LL HX). An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions at different effectiveness levels of the SL-LL HX.

[0297] (d) The operating conditions used for all tests were:

[0298] Condensation temperature = 45°C

[0299] Condensation temperature - ambient temperature = 10°C

[0300] Condenser subcooling = 0.0°C (system with receiver)

[0301] Evaporation temperature = -8°C,

[0302] Evaporator superheat = 5.5℃

[0303] Compressor isentropic efficiency = 65%

[0304] Volumetric efficiency = 100%

[0305] Temperature rise in the suction line = 10°C

[0306] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0307] The results are reported in Table E1A below.

[0308] Table E1A. Performance in medium temperature refrigeration system without SL / LL HX

[0309] refrigerant Efficiency, %R-134a Capacity, %R134a Evaporator slip, ℃ R134a 100％ 100％ 0 E1 100％ 74％ 1.3 E2A 100％ 73％ 1.8 E2B 100％ 73％ 1.8 E3 100％ 71％ 2.3 E4 100％ 70％ 2.8 E5 100％ 69％ 3.3 E6 100％ 67％ 3.8 E7 101％ 66％ 4.3

[0310] As revealed by the data reported in Table E1A, the refrigerants of the present invention (including E1 to E7 and refrigerants 1 to 10) are able to achieve a GWP (AR5) below 150 and have a flammability of Class A1, and also achieve efficiencies very close to R134a, capacities greater than 65%, and evaporator glide of 4.5 or less. This is an unexpected and highly desirable result. The refrigerants of the present invention represented by E1 to E5 achieve particularly unexpected and highly desirable performance because these refrigerants achieve the following highly desirable but very difficult to achieve combination of properties:

[0311] a.GWP(AR5)<150

[0312] b. Class A1 flammability

[0313] c. COP is 100

[0314] d. Capacity is 65% or more

[0315] e. Evaporator glide is 3.5℃ or lower

[0316] Particularly advantageous and unexpected results are achieved with refrigerants in the range represented by E1 to E3, particularly E2A and E2B, because they are able to achieve the following combination of properties:

[0317] a.GWP(AR5)<150

[0318] b. Class A1 flammability

[0319] c. COP is 100

[0320] d. Capacity is 70% or more

[0321] e. Evaporator glide is 2.5℃ or lower

[0322] Similar results as shown above were achieved when a suction line / liquid line heat exchanger was included in the system at 35%, 55% and 75% efficiencies, as reported in Tables E1B, E1C and E1D below.

[0323] Table E1B. Performance in a medium temperature refrigeration system with SL / LL HX35%

[0324] refrigerant Efficiency at 35% SL / LL HX effectiveness (% R-134a) Capacity, %R-134a Evaporator slip, ℃ R134a 100％ 100％ 0 E1 101％ 75％ 1.4 E2A 101％ 73％ 1.9 E2B 101％ 73％ 1.9 E3 101％ 72％ 2.5 E4 101％ 71％ 3.0 E5 101％ 69％ 3.5 E6 101％ 68％ 4.0 E7 102％ 67％ 4.5

[0325] Table E1C. Performance in a medium temperature refrigeration system with SL / LL HX55%

[0326] refrigerant Efficiency at 55% SL / LL HX effectiveness (% R-134a) Capacity, %R-134a Evaporator slip, ℃ R134a 100％ 100％ 0 E1 101％ 75％ 1.4 E2A 102％ 74％ 2.0 E2B 102％ 74％ 2.0 E3 102％ 73％ 2.6 E4 102％ 71％ 3.1 E5 102％ 70％ 3.6 E6 102％ 69％ 4.1 E7 102％ 67％ 4.6

[0327] Table E1D. Performance in a medium temperature refrigeration system with SL / LL HX75%

[0328] refrigerant Efficiency at 75% SL / LL HX effectiveness (% R-134a) Capacity, %R-134a Evaporator slip, ℃ R134a 100％ 100％ 0 E1 102％ 76％ 1.5 E2A 102％ 74％ 2.1 E2B 102％ 74％ 2.1 E3 102％ 73％ 2.6 E4 102％ 72％ 3.2 E5 102％ 70％ 3.7 E6 102％ 69％ 4.2 E7 103％ 68％ 4.7

[0329] Example C1A - Performance in a Medium Temperature Refrigeration System (e) Examples E1A to E1D were repeated, except that, for comparative purposes, the refrigeration

[0330] The GWP, capacity, COP and glide of refrigerants C4 and C5 are shown below. The C4 and C5 refrigerants were selected for comparison because those refrigerants have the lowest GWP among the refrigerants in Table C, but each of C4 and C5 has a GWP greater than 150, as reported in Tables C1A to C1D below. Tables C1A to C1D below also show the results for refrigerants E2B and E4 in each case as a representative comparison of the performance of the refrigerants of the present invention:

[0331] Table C1A. Comparative Performance in Medium Temperature Refrigeration Systems without SL / LL HX

[0332] refrigerant GWP(AR5) Efficiency, %R-134a Capacity, %R-134a Evaporator slip, ℃ R134a 1300 100％ 100％ 0 E2B 131 100％ 73％ 1.8 E4 131 100％ 70％ 2.8 C4 >150 102％ 63％ 4.9 C5 >150 103％ 65％ 5.2

[0333] As shown in Table C1A, C4 and C5 refrigerants (which consist of HFO-1234ze(E), 1224yd(Z) and HFC-134) cannot achieve a GWP less than 150, or an evaporator glide less than 4.5°C, or a capacity greater than 65%. This demonstrates some very unexpected and beneficial results for the refrigerants of the present invention. Similar unexpected advantages are achieved for systems with suction line / liquid line heat exchangers, as shown in Tables C1B to C1D below.

[0334] Table C1B. Comparative performance in medium temperature refrigeration system with SL / LL HX 35% efficiency

[0335]

[0336] Table C1C. Comparative performance in medium temperature refrigeration system with SL / LL HX55% efficiency

[0337]

[0338] Table C1D. Comparative performance in medium temperature refrigeration system with SL / LL HX 55% efficiency

[0339]

[0340] Example 2: Performance in a low temperature refrigeration system with and without a suction line / liquid line heat exchanger

[0341] The performance of refrigerants E1 to E7 was tested in a low temperature refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX). An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions at different effectiveness levels of the SL-LL HX.

[0342] The operating conditions are:

[0343] Condensation temperature = 45°C

[0344] Condensation temperature - ambient temperature = 10°C

[0345] Condenser subcooling = 0.0°C (system with receiver)

[0346] Evaporation temperature = -35°C, corresponding box temperature = -25°C

[0347] Evaporator superheat = 5.5℃

[0348] Compressor isentropic efficiency = 65%

[0349] Volumetric efficiency = 100%

[0350] Temperature rise in the suction line = 10°C

[0351] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0352] The results are reported in Table E2 below.

[0353] Table E2. Performance in a low temperature refrigeration system with SL / LL HX

[0354]

[0355]

[0356] Table 3 shows the performance of the refrigerants in a low temperature refrigeration system. It should be understood that the results under the column of SL-LLHX with "0%" efficiency represent a system without SL-LL HX, and when a SULL heat exchanger is used, refrigerants E1 to E7 show improved performance in terms of efficiency (COP) over R134a, wherein compositions E1 to E5 show excellent performance when all relevant performance factors are considered, for example, as explained in conjunction with Example 1.

[0357] Example 3: Performance in a medium temperature refrigeration system with two-stage vapor jet compression

[0358] The performance of refrigerants E1 to E7 was tested in a medium temperature refrigeration system with two-stage injection compression. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions. The operating conditions were:

[0359] Condensation temperature = 45°C

[0360] Condensation temperature - ambient temperature = 10°C

[0361] Condenser subcooling = 5.0℃

[0362] Evaporation temperature = -8°C, corresponding box temperature = 1.7°C

[0363] Evaporator superheat = 5.5℃

[0364] Compressor isentropic efficiency = 70%

[0365] Volumetric efficiency = 100%

[0366] Temperature rise in the suction line = 10°C

[0367] Steam jet heat exchanger (HX) effectiveness: 15%, 35%, 55%, 75%

[0368] The results are reported in Table E3 below.

[0369] Table E3. Performance in a medium temperature refrigeration system with two-stage compression and vapor injection

[0370]

[0371]

[0372] Table E3 shows the performance of the refrigerants in medium temperature refrigeration systems. In two-stage compression with vapor injection, compositions E1 to E7 show improved performance over R134a in terms of efficiency (COP), wherein compositions E1 to E5 show excellent performance when all relevant performance factors are considered, for example, as explained in conjunction with Example 1.

[0373] Example 4: Performance of the refrigerant of the present invention in a cascade refrigeration system

[0374] Cascade systems are typically used in applications where there is a large temperature difference (e.g., about 50°C to 80°C, such as about 60°C to 70°C) between the ambient temperature and the cabinet temperature (e.g., the temperature difference between the air side of the condenser of the high stage and the air side of the evaporator of the low stage). For example, a cascade system can be used to freeze products in a supermarket. In this example, exemplary compositions E1 to E7 of the present invention were tested as refrigerants in the high stage of a cascade refrigeration system, wherein each of the following compositions was used in the low stage: CO2, propane, R1234yf; R454C; and R455AC. In the following Tables E4A to E4E, the performance is compared with R-134a as a baseline refrigerant in the high stage and the low stage.

[0375] The operating conditions are:

[0376] Condensation temperature = 45°C

[0377] Advanced condensing temperature - ambient temperature = 10°C

[0378] · High-level condenser subcooling = 0.0°C (system with receiver)

[0379] Evaporation temperature = -30°C, corresponding box temperature = -18°C

[0380] Low-stage evaporator superheat = 3.3°C

[0381] Isentropic efficiency of high and low stage compressors = 65%

[0382] Volumetric efficiency = 100%

[0383] Temperature rise in the lower stage of the suction line = 15°C

[0384] Temperature rise in the suction line at the upper stage = 10°C

[0385] Intermediate heat exchanger condensing temperature with indicated low grade refrigerant = 0°C, 5°C and 10°C

[0386] Intermediate heat exchanger superheat = 3.3°C

[0387] Temperature difference in intermediate heat exchanger = 8°C

[0388] The performance results are reported in Tables E4A to E4E.

[0389] Table E4A - Performance of the Inventive Refrigerant in the High Stage of a Cascade Refrigeration System (Using CO2 in the Low Stage)

[0390]

[0391] Table E4B - Performance of the Inventive Refrigerant in the High Stage of a Cascade Refrigeration System (Propane is Used in the Low Stage)

[0392]

[0393] Table E4C - Performance of the refrigerants of the present invention in the upper stage of a cascade refrigeration system (lower stage use R1234yf)

[0394]

[0395]

[0396] Table E4D - Performance of the refrigerant of the present invention in the high stage of a cascade refrigeration system (R455A is used in the low stage)

[0397]

[0398] Table E4E - Performance of the refrigerant of the present invention in the high stage of a cascade refrigeration system (R454C is used in the low stage)

[0399]

[0400] Tables E4A to E4E show the performance of the refrigerants of the invention in the upper stage of a cascade refrigeration system, with various refrigerants used in the lower stage. These tables show that for different condensing temperatures of the lower stage cycle, refrigerants E1 to E7 match the efficiency of R134a, with compositions E1 to E5 showing superior performance when all relevant performance factors are considered, e.g., as explained in conjunction with Example 1.

[0401] Example 5: Performance in a vending machine with / without suction line / liquid line heat exchanger

[0402] The performance of refrigerants E1 to E7 was tested in a vending machine refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX). An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system at different effectiveness levels of the SL-LL HX under the following conditions.

[0403] Operating conditions:

[0404] Condensation temperature = 45°C

[0405] Condensation temperature - ambient temperature = 10°C

[0406] Condenser subcooling = 5.5°C

[0407] Evaporation temperature = -8°C,

[0408] Evaporator superheat = 3.5℃

[0409] Compressor isentropic efficiency = 60%

[0410] Volumetric efficiency = 100%

[0411] Temperature rise in the suction line = 5°C

[0412] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0413] The performance results are reported in Table E5 below.

[0414] Table E5 - In case of SL / LL Performance of HX in vending machines

[0415]

[0416] Table E5 shows the performance of refrigerants E1 to E7 in vending machine systems with and without SL / LL HX. It should be understood that the results under the column of SL-LL HX with "0%" efficiency represent systems without SL-LL HX, and that refrigerants E1 to E7 show improved performance in terms of efficiency (COP) over R134a when using a SL / LL heat exchanger, with compositions E1 to E5 showing superior performance when all relevant performance factors are considered, for example, as explained in conjunction with Example 1.

[0417] Example 6: Performance in an air source heat pump water heater

[0418] Refrigerants E1 to E7 were tested for performance in an air source heat pump water heater system. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in the system under the following conditions.

[0419] The operating conditions are:

[0420] Condensation temperature = 55°C

[0421] Water inlet temperature = 45°C, water outlet temperature = 50°C

[0422] Condenser subcooling = 5.0℃

[0423] Evaporation temperature = -5°C, corresponding ambient temperature = 10°C

[0424] Evaporator superheat = 3.5℃

[0425] Compressor isentropic efficiency = 65%

[0426] Volumetric efficiency = 100%

[0427] Temperature rise in the suction line = 5°C

[0428] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0429] The performance results are reported in Table E6 below.

[0430] Table E6 - Performance in heat pump water heaters

[0431] refrigerant Efficiency (%R-134a) Comparative discharge temperature (℃) R134a 100％ 88.0 E1 100％ 79.7 E2A 100％ 80.1 E2B 100％ 80.1 E3 100％ 80.5 E4 100％ 80.9 E5 100％ 81.3 E6 100％ 81.6 E7 100％ 82.0

[0432] Table E6 shows the performance of refrigerants E1 to E7 in a heat pump water heater. Refrigerants E1 to E6 show similar efficiencies to R134a, and compositions E1 to E5 show superior performance when all relevant performance factors are considered, e.g., as explained in conjunction with Example 1. Refrigerants E1 to E7 show lower discharge temperatures than R134a, which indicates better reliability of the compressor.

[0433] Example 7: Performance in an air source heat pump water heater with a suction line / liquid line heat exchanger

[0434] The performance of refrigerants E1 to E7 was tested in an air source heat pump water heater system with and without a suction line / liquid line heat exchanger (SL / LL HX). An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions at different effectiveness levels of the SL-LL HX.

[0435] The operating conditions are:

[0436] Condensation temperature = 55°C

[0437] Water inlet temperature = 45°C, water outlet temperature = 50°C

[0438] Condenser subcooling = 5.0℃

[0439] Evaporation temperature = -5°C, corresponding ambient temperature = 10°C

[0440] Evaporator superheat = 3.5℃

[0441] Compressor isentropic efficiency = 65%

[0442] Volumetric efficiency = 100%

[0443] Temperature rise in the suction line = 5°C

[0444] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0445] The performance results are reported in Table E7 below.

[0446] Table E7 - In case of SL / LL Performance of HX heat pump water heater

[0447]

[0448]

[0449] Table E7 shows the performance of the refrigerants in a heat pump water heater with SL / LL HX. When the SL / LL heat exchanger is employed, refrigerants E1 to E7 show higher efficiency than R134a, and compositions E1 to E5 show excellent performance when all relevant performance factors are considered, for example, as explained in conjunction with Example 1. Refrigerants E1 to E7 show lower discharge temperatures than R134a, which indicates better reliability of the compressor.

[0450] Example 8: Performance in mobile air conditioning systems (buses, trains, cars)

[0451] The performance of refrigerants E1 to E6 was tested at various condenser temperature conditions in a mobile air conditioning system. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E6 in this system under the following operating conditions:

[0452] Condensation temperature = 45°C to 75°C

[0453] Condenser subcooling = 5.0℃

[0454] Evaporation temperature = 4°C, corresponding box temperature = 35°C

[0455] Evaporator superheat = 5.0℃

[0456] Compressor isentropic efficiency = 65%

[0457] Volumetric efficiency = 100%

[0458] Temperature rise in the suction line = 0°C

[0459] The performance results are reported in Table E8 below.

[0460] Table E5 - Performance in mobile AC systems

[0461]

[0462] In Table E8, refrigerants E1 to E7 show similar efficiencies to R134a over a range of condensing temperatures corresponding to different ambient temperatures, wherein compositions E1 to E5 show superior performance when all relevant performance factors are considered, e.g. as explained in conjunction with Example 1.

[0463] Example 9: Performance of the refrigerant of the present invention in a micro-cascade refrigeration system

[0464] The micro-cascade system combines a conventional medium temperature DX refrigeration system, with or without a suction line liquid line heat exchanger (SLHX), operating with refrigerants E1 to E7 in the high stage of the micro-cascade system, and contains several small low temperature self-contained refrigeration systems in the low stage, which operate the following refrigerants in the low stage: CO2; propane; R1234yf; R454C and R455A. As used herein, the term "medium temperature DX refrigeration system" refers to a medium temperature system in which the evaporator is a dry evaporator. Useful micro-cascade systems are disclosed in U.S. Serial Nos. 16 / 014,863, filed on June 21, 2018, and 16 / 015,145, filed on June 21, 2018, which claim priority to U.S. Serial Nos. 62 / 522386, filed on June 21, 2017, 62 / 522846, filed on June 21, 2017, 62 / 522851, filed on June 21, 2017, and 62 / 522860, filed on June 21, 2017, all of which are incorporated herein by reference in their entirety. For comparison purposes, a baseline system operating with R-404A was also tested, operating in a single high capacity vapor compressor in the high stage and in the low stage.

[0465] Operating conditions:

[0466] Baseline R404A for combined MT and LT (non-micro) systems

[0467] Refrigeration capacity

[0468] ○ Low temperature: 33,000W

[0469] ○Medium temperature: 67,000W

[0470] Volumetric efficiency: 95% for both MT and LT

[0471] Isentropic efficiency of compressor

[0472] ○Medium temperature = 70% and low temperature = 67%

[0473] Condensation temperature: 105°F

[0474] Medium evaporation temperature: 20℉

[0475] Low temperature evaporation temperature: -20℉

[0476] Evaporator superheat: 10℉ (both medium and low temperatures)

[0477] Suction line temperature rise (due to heat transfer to the surrounding environment)

[0478] ○ Baseline: Medium temperature: 25℉; Low temperature: 50℉

[0479] ○ Cascade / Self-contained without SLHX: Medium temperature: 10℉; Low temperature: 25℉

[0480] ○Cascade / Self-Contained with SLHX: Medium Temperature: 10℉; Low Temperature: 15℉

[0481] SLHX efficiency when in use: 65%

[0482] The performance results are reported in Tables E9A to E9E below.

[0483] Table E9A - R404A and Micro-Cascade System (Using the Refrigerant of the Invention in the High Stage and CO2 in the Low Stage) Comparison between

[0484]

[0485] Table E9B - R404A and Micro-Cascade System (Using the Refrigerant of the Invention in the High Stage and Propane in the Low Stage) Comparison between

[0486]

[0487] Table E9C - R404A and micro-cascade system (using the refrigerant of the present invention in the high stage and using the refrigerant in the low stage) Comparison between

[0488]

[0489]

[0490] Table E9D - R404A and micro-cascade system (using the refrigerant of the present invention in the high stage and using the refrigerant in the low stage) Comparison between R454C)

[0491]

[0492] Table E9E - R404A and micro-cascade system (using the refrigerant of the present invention in the high stage and R- 455A)

[0493]

[0494] Tables E9A to E9E above show that the mini-cascade system has a COP that is about at least 120% higher than the baseline medium temperature DX system using R404A.

[0495] Example 10: Non-flammable secondary refrigerant at pressure above atmospheric pressure

[0496] The refrigerants of the present invention (including refrigerants E1 to E7) can be used as secondary fluids in secondary fluid refrigeration systems. The refrigerants of the present invention (including each of refrigerants E1 and E7) have the necessary properties to ensure that the operating pressure of the refrigerant is not less than atmospheric pressure at a given evaporator temperature so that air does not enter the system, and at the same time the pressure is low enough to prevent significant leakage.

[0497] • Table 10 shows the pressures for refrigerants with evaporating temperatures ranging from -5°C to 10°C, which covers various operating conditions for air conditioning applications.

[0498] It can be observed from Table 10 that all refrigerants maintain a pressure higher than atmospheric pressure.

[0499] The primary refrigerant used in the vapour compression circuit may be selected from the group consisting of:

[0500] R404A, R507, R410A, R455A, R32, R466A, R44B, R290, R717, R452B, R448A, R1234ze(E), R1234yf and R449A.

[0501] • The temperature of the air (or body) to be cooled may be from about 25°C to about 0°C.

[0502] Table 10: Secondary Fluids

[0503]

[0504] Example 11: Performance in a stationary air conditioning system

[0505] The performance of refrigerants E1 to E7 was tested at various condenser temperature conditions in a stationary air conditioning system. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions. Operating Conditions:

[0506] Condensation temperature = 45°C to 65°C

[0507] Condenser subcooling = 5.0℃

[0508] Evaporation temperature = 10°C, corresponding box temperature = 35°C

[0509] Evaporator superheat = 5.0℃

[0510] Compressor isentropic efficiency = 72%

[0511] Volumetric efficiency = 100%

[0512] Table 11. Performance in fixed AC systems

[0513]

[0514] Refrigerants E1 to E7 show similar efficiencies to R134a over a condensing temperature range corresponding to different ambient temperatures, wherein compositions E1 to E5 show superior performance when all relevant performance factors are considered, for example as explained in conjunction with Example 1.

[0515] Example 12: Performance in a Commercial Air Conditioning System

[0516] The performance of refrigerants E1 to E7 was tested under various condenser temperature conditions in a commercial air conditioning system. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions.

[0517] Operating conditions:

[0518] Condensation temperature = 45°C to 65°C

[0519] Condenser subcooling = 5.0℃

[0520] Evaporation temperature = 10°C,

[0521] Evaporator superheat = 5.0℃

[0522] Compressor isentropic efficiency = 72%

[0523] Volumetric efficiency = 100%

[0524] Table 12. Performance in mobile AC systems

[0525]

[0526]

[0527] Refrigerants E1 to E6 show similar efficiencies to R134a over a condensing temperature range corresponding to different ambient temperatures, wherein compositions E1, E2, E3 and E4 show superior performance when all relevant performance factors are considered, e.g. as explained in conjunction with Example 1.

[0528] Example 13: Performance in Extreme Temperature Air Conditioning Systems

[0529] The performance of refrigerants E1 to E7 was tested at various condenser temperature conditions in a stationary air conditioning system. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions. Operating Conditions:

[0530] Condensation temperature = 55°C to 95°C

[0531] Condenser subcooling = 5.0℃

[0532] Evaporation temperature = 10°C, corresponding box temperature = 35°C

[0533] Evaporator superheat = 5.0℃

[0534] Compressor isentropic efficiency = 65%

[0535] Volumetric efficiency = 100%

[0536] Table 13. Performance in fixed AC systems

[0537]

[0538] Refrigerants E1 to E7 show similar efficiencies to R134a over a condensing temperature range corresponding to different ambient temperatures, wherein compositions E1 to E5 show superior performance when all relevant performance factors are considered, for example as explained in conjunction with Example 1.

[0539] Comparative Example C2 - Performance in Extreme Temperature Air Conditioning Systems

[0540] Example E13 was repeated with a condenser temperature of 75°C, except that the GWP, capacity, COP and glide of refrigerants C4 and C5 were tested for comparison purposes. The C4 and C5 refrigerants were selected for comparison because those refrigerants had the lowest GWP among the refrigerants in Table C, but each of C4 and C5 had a GWP greater than 150, as reported in Table C2. Table C2 below also shows the results for refrigerants E2B and E4 in each case, as a representative comparison of the performance of the refrigerants of the present invention:

[0541] Table C2. Comparative performance in extreme air conditioning systems

[0542] refrigerant GWP(AR5) efficiency capacity Evaporator slip, ℃ R134a 1300 100％ 100％ 0 E2B 131 101％ 74％ 1.6 E4 131 101％ 72％ 2.3 C4 >150 105％ 66％ 4.1 C5 >150 107％ 70％ 4.5

[0543] As shown in Table C2, C4 and C5 refrigerants (which consist of HFO-1234ze(E), 1224yd(Z), and HFC-134) cannot achieve a GWP of less than 150, or an evaporator glide of less than 3°C, a capacity greater than 70%, or an efficiency that matches that of R134a, such as being close to that of E2B or E4. This demonstrates very unexpected and advantageous results for the refrigerants of the present invention.

[0544] Example 14: Performance in a high temperature heat pump system

[0545] The performance of refrigerants E1 to E7 was tested at various condenser temperature conditions in a stationary air conditioning system. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions. Operating Conditions:

[0546] Condensation temperature = 55°C to 95°C

[0547] Condenser subcooling = 5.0℃

[0548] Evaporation temperature: 30℃

[0549] Evaporator superheat = 5.0℃

[0550] Compressor isentropic efficiency = 65%

[0551] Volumetric efficiency = 100%

[0552] Table 14. Performance in high temperature heat pump system

[0553]

[0554] Refrigerants E1 to E7 show similar efficiencies to R134a in a condensing temperature range corresponding to different ambient temperatures, wherein compositions E1 to E5 show superior performance when all relevant performance factors are considered, for example as explained in conjunction with Example E1.

[0555] Comparative Example C3 - Performance in a High Temperature Heat Pump System

[0556] Example E14 was repeated with a condenser temperature of 75°C, except that the GWP, capacity, COP and glide of refrigerants C4 and C5 were tested for comparison purposes. The C4 and C5 refrigerants were selected for comparison because those refrigerants had the lowest GWP among the refrigerants in Table C, but each of C4 and C5 had a GWP greater than 150, as reported in Table C3. Table C3 below also shows the results for refrigerants E2B and E4 in each case, as representative of the performance of the refrigerants of the present invention for comparison:

[0557] Table C3. Comparative performance in extreme air conditioning systems

[0558] refrigerant GWP(AR5) capacity efficiency Evaporator slip, ℃ R134a 1300 100％ 100％ 0 E2B 131 76％ 102％ 1.6 E4 131 74％ 102％ 2.4 C4 >150 68％ 104％ 4.2 C5 >150 70％ 105％ 4.6

[0559] As shown in Table C3, C4 and C5 refrigerants (which consist of HFO-1234ze(E), 1224yd(Z) and HFC-134) cannot achieve a GWP less than 150, or an evaporator glide less than 3°C, a capacity greater than 70%, or an efficiency that matches that of R134a, such as being close to that of E2B or E4. This demonstrates very unexpected and advantageous results for the refrigerants of the present invention.

[0560] Example 15: Transport (cold) with and without suction line (SL) / liquid line (LL) heat exchanger (HX) Performance in medium temperature refrigeration applications (storehouse, container)

[0561] The performance of refrigerants E1 to E7 was tested in a transport refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX) under medium temperature refrigeration conditions. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions at different effectiveness levels of the SL-LL HX.

[0562] The operating conditions are:

[0563] Condensation temperature = 45°C

[0564] Condensation temperature - ambient temperature = 10°C

[0565] Condenser subcooling = 0.0°C (system with receiver)

[0566] Evaporation temperature = -8°C,

[0567] Evaporator superheat = 5.5℃

[0568] Compressor isentropic efficiency = 65%

[0569] Volumetric efficiency = 100%

[0570] Temperature rise in the suction line = 15°C

[0571] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0572] Table 15. Performance in medium temperature transport refrigeration system with SL / LL HX

[0573]

[0574] Table 15 shows the performance of refrigerants E1 to E7 in transport refrigeration systems. It should be understood that the results under the column of SL-LL HX with "0%" efficiency represent systems without SL-LL HX, and that refrigerants E1 to E7 show improved performance in terms of efficiency (COP) over R134a when using SL / LL heat exchangers, with compositions E1 to E5 showing superior performance when all relevant performance factors are considered, for example, as explained in conjunction with Example E1.

[0575] Example 16: Transport (refrigerated truck, container) with and without suction line / liquid line heat exchanger Performance in temperature refrigeration applications

[0576] The performance of refrigerants E1 to E6 was tested in a transport refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX) under low temperature refrigeration conditions. An analysis was performed to estimate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions at different effectiveness levels of the SL-LL HX.

[0577] The operating conditions are:

[0578] Condensation temperature = 45°C

[0579] Condensation temperature - ambient temperature = 10°C

[0580] Condenser subcooling = 0.0°C (system with receiver)

[0581] Evaporation temperature = -35°C, corresponding box temperature = -25°C

[0582] Evaporator superheat = 5.5℃

[0583] Compressor isentropic efficiency = 65%

[0584] Volumetric efficiency = 100%

[0585] Temperature rise in the suction line = 15°C

[0586] Suction line / liquid line heat exchanger effectiveness: 0%, 35%, 55%, 75%

[0587] Table 16. In the case of SL / LL Performance of HX in cryogenic transport refrigeration systems

[0588]

[0589] It should be understood that the results under the column of SL-LL HX with "0%" efficiency represent a system without SL-LL HX, and that refrigerants E1 to E7 show improved performance in terms of efficiency (COP) over R134a when using a SULL heat exchanger, with compositions E1 to E5 showing superior performance when all relevant performance factors are considered, for example, as explained in conjunction with Example E1.

[0590] Example 17: Cooling of electronic devices

[0591] Refrigerants E1 to E7 were tested for performance to evaluate cooling of electronic devices including heat pipes, thermosyphons, etc. (including chip cooling, electronic board cooling, battery cooling (including batteries used in cars, trucks, buses and other electronic transportation vehicles) cooling, computer cooling, etc.), and vapor compression cooling. Analysis was performed to estimate the performance of refrigerants E1 to E6 in these applications. Refrigerants E1 to E7 showed similar performance to R134a, and compositions E1 to E5 showed excellent performance when all relevant performance factors were considered, for example, as explained in conjunction with Example E1.

[0592] Example 18: Performance of the paired refrigerants of the present invention in a cascade refrigeration system

[0593] As mentioned above, cascade systems are typically used for applications where there is a large temperature difference (e.g., about 50°C to 80°C, such as about 60°C to 70°C) between the ambient temperature and the cabinet temperature (e.g., the temperature difference between the air side of the high-stage condenser and the air side of the low-stage evaporator). For example, a cascade system can be used to freeze products in a supermarket. In this example, the high-stage / low-stage paired refrigerant of the present invention was tested in a cascade refrigeration system, using R-134a as a baseline in the high stage and CO2 in the low stage. The operating conditions were:

[0594] Condensation temperature = 45°C

[0595] Advanced condensing temperature - ambient temperature = 10°C

[0596] · High-level condenser subcooling = 0.0°C (system with receiver)

[0597] Evaporation temperature = -30°C, corresponding box temperature = -18°C

[0598] Low-stage evaporator superheat = 3.3°C

[0599] Isentropic efficiency of high and low stage compressors = 65%

[0600] Volumetric efficiency = 100%

[0601] Temperature rise in the lower stage of the suction line = 15°C

[0602] Temperature rise in the suction line at the upper stage = 10°C

[0603] Intermediate heat exchanger condensing temperature with indicated low grade refrigerant = 0°C, 5°C and 10°C

[0604] Intermediate heat exchanger superheat = 3.3°C

[0605] Temperature difference in intermediate heat exchanger = 8°C

[0606] The performance results are reported in Table E18.

[0607] Table E18 - Performance of paired refrigerants of the present invention in cascade refrigeration systems

[0608]

[0609] Example 19: Micro Cascade Refrigeration System

[0610] The micro-cascade system incorporates a conventional medium temperature DX refrigeration system, with or without a suction line liquid line heat exchanger (SLHX). In this example, advantageous combinations of the inventive paired refrigerants in the high and low stages were tested, as shown in Table 19 below. The low stage included several small low temperature self-contained refrigeration systems. For comparison purposes, a baseline system operating with R-404A was also tested, with R-404A operating in the high and low stages.

[0611] Operating conditions:

[0612] Baseline R404A for combined MT and LT (non-micro) systems

[0613] Refrigeration capacity

[0614] ○ Low temperature: 33,000W

[0615] ○Medium temperature: 67,000W

[0616] Volumetric efficiency: 95% for both MT and LT

[0617] Isentropic efficiency of compressor

[0618] ○Medium temperature = 70% and low temperature = 67%

[0619] Condensation temperature: 105°F

[0620] Medium evaporation temperature: 20℉

[0621] Low temperature evaporation temperature: -20℉, evaporator overheat: 10℉ (both medium and low temperature)

[0622] Suction line temperature rise (due to heat transfer to the surrounding environment)

[0623] ○ Baseline: Medium temperature: 25℉; Low temperature: 50℉

[0624] ○ Cascade / Self-contained without SLHX: Medium temperature: 10℉; Low temperature: 25℉

[0625] ○Cascade / Self-Contained with SLHX: Medium Temperature: 10℉; Low Temperature: 15℉

[0626] SLHX efficiency when in use: 65%

[0627] The performance results are reported in Table E19.

[0628] Table E19 - Comparison of the use of R404A in the low and high stages and the use of this in the high and low stages in a micro-cascade system Comparison between inventive pairs of refrigerants

[0629]

[0630]

[0631] Table E19 above shows that the mini-cascade system using the paired refrigerants according to the present invention has a COP that is at least about 120% higher than the baseline medium temperature DX system using R404A.

Claims

1. A refrigerant, the refrigerant essentially consisting of: a. about 74 wt % to about 86 wt % HFO-1234ze(E), b. greater than 4 wt % to less than 11 wt % HFC-134a; and c. Greater than 4 wt % to about 16 wt % HFO-1224yd(Z).

2. The refrigerant according to claim 1, consisting essentially of: a. about 76 wt % to about 84 wt % HFO-1234ze(E), b. 11 wt% or less HFC-134a; and c. 14 wt% or less HFO-1224yd(Z).

3. The refrigerant of claim 1, consisting essentially of: a. 83.5 wt% + 0.5 wt% / - 2 wt% HFO-1234ze (E), b. 10 wt% + 2 wt% / - 0.5 wt% HFC-134a; and c. 6.5 wt% + 2 wt% / - 0.5 wt% HFO-1224yd (Z).

4. The refrigerant of claim 1 having an evaporator glide of less than 4°C, a GWP of less than 150, and a flammability classification of A1.

5. A method of providing heating and / or cooling, the method comprising: a. Providing a vapor compression refrigeration system, the vapor compression refrigeration system comprising a compressor, a condenser, an evaporator and a refrigerant, the refrigerant comprising: i. from about 74 wt % to less than 87 wt % HFO-1234ze(E); ii. greater than 4 wt% to less than 11 wt% HFC-134a; and iii. greater than 3 wt % to about 16 wt % HFO-1224yd(Z); b. evaporating the refrigerant in the evaporator, wherein the glide of the refrigerant in the evaporator is less than 4.5°C, and wherein the capacity of the refrigerant in the system is greater than 65% of the capacity of R-134a in the system.

6. A cascade refrigeration system, comprising: (f) a low-stage refrigeration circuit, the low-stage refrigeration circuit comprising: Low-grade refrigerants with a GWP of about 150 or less; and compressor; (g) an inter-circuit heat exchanger in which the low-grade refrigerant is condensed; and (h) a high-grade refrigeration circuit comprising a high-grade refrigerant, the high-grade refrigerant: (i) having a Class A1 or Class A2L flammability; and (ii) vaporizing at a temperature below the condensation temperature of the low-grade refrigerant; and (iii) containing at least about 74 weight percent HFO-1234ze(E), wherein the high-grade refrigerant vaporizes in the inter-circuit heat exchanger by absorbing heat from the refrigerant in the low-grade refrigeration circuit.

7. The cascade refrigeration system according to claim 9, wherein the low-grade refrigerant is an A1 or A2L refrigerant.

8. The cascade refrigeration system of claim 9, wherein the high-grade refrigerant is a Class A1 refrigerant and comprises at least about 75 weight percent HFO-1234ze(E) and about 5 to less than 12 weight percent HFC-134a.

9. The cascade refrigeration system of claim 12, wherein the low-grade refrigerant comprises one or more of CO2, propane, HFO-1234yf, R454C, and R455A, and is condensed in the inter-circuit heat exchanger at a temperature range of about -5°C to about -15°C.

10. A commercial refrigeration system comprising the cascade refrigeration system according to claim 9.

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