Refrigeration system and method

Abstract

Disclosed is a refrigeration and cooling system including a cascade type refrigeration system comprising a plurality of cooling units including a first refrigeration circuit, each cooling unit including a first refrigeration circuit, each first refrigeration circuit including an evaporator and a heat exchanger, and a second refrigeration circuit, each first circuit heat exchanger being disposed to transfer thermal energy between its respective first refrigeration circuit and the second refrigeration circuit.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application is related to and incorporates by reference U.S. Provisional Application No. 63 / 344,542, filed May 21, 2022, and U.S. Provisional Application No. 63 / 432,882, filed December 15, 2022.

[0002] FIELD OF THEINVENTION The present invention relates to highly efficient, low-Global Warming Potential ("low-GWP") refrigerants, and air conditioning and / or refrigeration systems and methods for providing safe and effective cooling. Certain embodiments relate to commercial refrigeration and cascade refrigeration systems and methods, and more particularly, but not exclusively, to commercial refrigeration (including commercial cascade refrigeration systems and methods) that have exceptional performance when used with certain low-GWP refrigerants. [Background technology]

[0003] The refrigeration industry is under increasing pressure, including through regulatory changes, to replace refrigerants having relatively high Global Warming Potential (GWP) values, such as HFC-134a and R404A, with materials having lower GWPs. Under many current and future contemplated regulations, refrigerants are required to have a GWP of less than 150. The use of refrigerants having GWP values ​​of less than 150 is particularly important in commercial refrigeration systems where large volumes of refrigerants are used and where the potential negative environmental impacts are significant if refrigerants having substantially higher GWPs are used.

[0004] One approach is to use low GWP refrigerants such as carbon dioxide (R744) refrigerants and hydrocarbon refrigerants. However, approaches as used heretofore can suffer from significant safety and financial drawbacks, such as increased operating costs due to low system energy efficiency, high initial system costs due to high system complexity, high maintenance costs due to low system availability and reliability, and high system flammability. Systems with highly flammable refrigerants in conventional configurations have been particularly disadvantageous because they can reduce safety levels, violate regulatory code constraints, and increase liability for refrigeration system operators and manufacturers. Safety is of particular concern given that many commercial refrigeration applications, such as supermarket refrigerators, coolers, and refrigerated display cases, are publicly available and often operate in densely populated spaces.

[0005] Another approach has been to provide new refrigerants with a GWP lower than that of HFC-134a, but this approach has often not been successful in producing refrigerants with a GWP value of 150 or less. For example, U.S. Patent Application No. 2021 / 0198547 discloses an attempt to provide a refrigerant with a GWP lower than that of HFC-134a by using a refrigerant blend including HFO-1234ze(E) and HFC-134, while also providing efficiency equivalent to or higher than that of HFC-134a. However, this effort was ineffective in that it did not reveal the ability to provide a refrigerant with a GWP of less than 150 that also provides other desirable qualities such as non-flammability and good heat transfer performance. In particular, the '547 patent application discloses eleven specific refrigerant blends, all of which have a GWP greater than 300. Thus, at least in this sense, the refrigerants of the '547 patent application do not achieve the combination of properties including a GWP of less than 150 that is the objective of the preferred embodiment of the present invention. For example, a refrigerant is disclosed that contains 63 wt% HFO-1234ze(E), 35 wt% HFC-134, and 2 wt% R1244yd, the refrigerant blend having a GWP of 389. Similar ineffective results are disclosed for the ten other blends specifically disclosed in the '547 patent application.

[0006] Applicants have therefore come to recognize that the refrigeration industry continues to need a safe, robust, and sustainable approach to reducing the use of high GWP refrigerants that may be used with existing technology, particularly refrigerants that have a GWP of less than 150 while at the same time offering 65% or more capacity, non-flammability, and a relatively low gradient compared to conventional refrigerants (including R-134a).

[0007] The prior art has also sought an improved cascade refrigeration system that provides advantageous operation in terms of environmental friendliness. One example of a typical cascade refrigeration system is a system 100 of the type commonly used for commercial refrigeration in supermarkets, as shown in FIG. 6A. The system 100 is a direct expansion system that provides both medium 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 both medium temperature cooling and removes waste heat from the lower temperature refrigeration circuit 120 via heat exchanger 130. The medium temperature refrigeration circuit 110 extends between a roof 140, a machine room 141, and a sales floor 142. Meanwhile, 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 floor 142. Usefully, as noted above, R744 has a low GWP.

[0008] However, while refrigeration systems of the type disclosed in FIG. 6A may be capable of providing good efficiency levels, Applicants have realised that this type of system has at least two major drawbacks: first, such systems use the high GWP refrigerant R134a (R134a has a GWP of about 1300); and second, even though the low temperature portions of such systems use the low GWP refrigerant R744, this refrigerant exhibits many of the drawbacks discussed above, including significant safety and financial drawbacks.

[0009] Additionally, in certain refrigeration applications, it is necessary to cool items, but without exposing those items to temperatures below a certain temperature, such as the freezing point of water. For example, in a supermarket environment, it is common to keep certain products at a low temperature relative to the surroundings, but at the same time, it is disadvantageous to cool that product below the freezing point of water, especially since the preferred method of cooling involves indirect cooling with moist, ambient air. For these applications, it is also disadvantageous to have a refrigerant temperature below the freezing point of water along the evaporator, as this would cause frost buildup and the resulting need to defrost the equipment. Avoiding frost buildup is an important aspect in those applications. Similarly, cooling of beverages, including water, etc., should also be done under conditions that avoid exposing such products to temperatures below the freezing point of water, as freezing of such products is undesirable at the point of sale. For convenience, applicants refer to such applications, methods, and systems herein as "no-freeze" applications, methods, and systems.

[0010] Certain single component fluorocarbons, including chlorofluorocarbons ("CFCs"), hydrochlorofluorocarbons ("HCFCs"), and hydrofluoroolefins ("HFOs"), have been used in "no frost" applications where the refrigerant temperature along the evaporator must remain above the freezing point of water so that frost does not build up on the coil surface, thereby eliminating the need for a defroster; in such refrigeration applications, systems, and methods, the use of single component fluids has been considered particularly desirable because the saturation temperature of such fluids does not change upon evaporation of the fluid at constant pressure. The use of single component fluids is highly desirable because it allows systems and methods to be designed with a refrigerant temperature along the evaporator that remains essentially constant during the evaporation process and is above the freezing point of water, assuming little or no pressure drop as the refrigerant flows through the evaporator. It should be noted that product applications also typically require a small temperature difference between the air and the refrigerant to dehumidify the air and reduce the resulting moisture content removal and loss of product quality. The requirement for low temperature differential and frost avoidance, combined with the need for the evaporator to have a certain positive superheat at the outlet, is important when selecting a particular refrigerant. A superheat below zero, i.e., where the refrigerant is not superheated, can lead to reduced cooling capacity, efficiency, and potential compressor failure. The term "degree of superheat" or simply "superheat" refers to the temperature rise of the refrigerant at the outlet of the evaporator above the saturated vapor temperature (or dew point temperature) of the refrigerant.

[0011] This is shown by way of example in Figure 6B, which represents in schematic form a typical supermarket produce cooling case. Typically, as shown in Figure 6, cooled humid air is provided to the product display zone of the display case by passing both air from outside the case 102 and from recirculating air 104 over the heat exchange surface of an evaporator coil 106, which is typically located within the display case in an area separate from, but adjacent to, the product display zone (or at least hidden from the consumer's view). The evaporator 106 has a single component refrigerant inlet 108 and a single component refrigerant outlet 110. A circulating fan 114 is also used. It is highly desirable in systems of the above example type that the cooling space 112 in the refrigeration system has a refrigerant temperature always or substantially always above a certain level along the evaporator. For example, in many applications, such as produce refrigeration, the minimum discharge (outlet) temperature of the air within the display case is set by design at about 2°C to 3°C to provide a safety margin to avoid having the cooling space or cooling items below the freezing point of water. Furthermore, to minimize the removal of moisture from the air and the resulting drying of the produce (quality 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 evaporators in these applications require a degree of superheat of about 3 to about 5° C., will impose constraints on the allowable evaporator gradient of the refrigerant so that the evaporation temperature remains above the freezing point of water and, as a result, frost does not accumulate.

[0012] Those skilled in the art will appreciate that these two desirable results have often made it very difficult in the past to provide a refrigerant that is a multi-component blend of different single component refrigerants.

[0013] For example, HFC-134a has traditionally been used in certain non-freezing applications, but nevertheless does not meet, for example, the low GWP requirement (item 4 above) because HFC-134a has a GWP of about 1300.

[0014] Applicants have gone against conventional wisdom and discovered unexpected and advantageous results. For example, Applicants have found that certain blends, including carefully selected combinations of components, as described in detail below, can have advantageous, yet unexpected, combinations of non-flammability while at the same time having, among other things, excellent heat transfer properties, low GWP (e.g., GWP less than about 150), low or no toxicity, chemical stability, and lubricant compatibility. Furthermore, Applicants have found that the refrigerant compositions of the present invention have particular advantages for use in medium temperature refrigeration systems, and in particular in medium temperature refrigeration systems where certain embodiments are desirable to maintain the temperature of the refrigerated air above about 0° C. and also to avoid exposing the refrigerated air to temperatures below about 0° C. in order to protect the goods being refrigerated from frost and / or to prevent frosting of the evaporator coils, which in themselves can adversely affect the overall efficiency of such systems due to the need for defrosting and / or inconsistent cooling across the coils.

[0015] One or more of these and other unmet needs in the prior art are met by the present invention, as described in detail herein. Summary of the Invention

[0016] Applicants have discovered refrigerant compositions, heat transfer compositions comprising refrigerants, cooling methods and systems including cascaded heat transfer methods and systems, and / or methods and systems for cooling materials having low temperature constraints, such as the low temperature or non-freezing applications described above.

[0017] Mid-temperature refrigeration systems and methods, as well as commercial refrigeration systems and methods, are also provided by the present invention, as described in detail below.

[0018] 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 gradient 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 can achieve an unexpectedly small change in refrigerant temperature through the evaporator.

[0019] The present invention also provides about 75% by weight to about 86% by weight of HFO-1234ze(E); 5% to less than 11% by weight of HFC-134a; and about 5% to about 16% by weight of HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 1.

[0020] The present invention also provides 74% to 86% by weight of HFO-1234ze(E); 5% to 10% by weight of HFC-134a; 4% to 16% by weight of HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 2.

[0021] The present invention also provides 76% to 86% by weight of HFO-1234ze(E); about 10% by weight or less of HFC-134a; 4% to 14% by weight of HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 3.

[0022] The present invention also provides About 78% to 86% by weight of HFO-1234ze(E); about 10% by weight or less of HFC-134a; 4% to about 12% by weight of HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 4.

[0023] The present invention also provides Approximately 84% by weight of HFO-1234ze(E); 10% by weight or less of HFC-134a; and about 6 wt. % HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 5.

[0024] The present invention also provides Approximately 82% by weight of HFO-1234ze(E); 10% by weight or less of HFC-134a; and about 8% by weight of HFO-1224yd(Z). The refrigerant according to this paragraph may be referred to herein for convenience as Refrigerant 6.

[0025] The present invention also provides Approximately 80% by weight of HFO-1234ze(E); 10% by weight or less of HFC-134a; and about 10% by weight of HFO-1224yd(Z). The refrigerant according to this paragraph may be referred to herein for convenience as Refrigerant 7.

[0026] The present invention also provides 84wt%+2wt% / -2wt% HFO-1234ze(E); 10% by weight + 0.5% by weight / - 2% by weight of HFC-134a; 6%+2% / -2% by weight of HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 8A.

[0027] The present invention also provides 83.5wt% + 0.5wt% / - 2wt% HFO-1234ze(E); 10% by weight + 2% by weight / - 0.5% by weight of HFC-134a; 6.5wt%+2wt% / -0.5wt% HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 8B.

[0028] The present invention also provides 83.5wt% + 0.5wt% / - 2wt% HFO-1234ze(E); 10% by weight + 2% by weight / - 0.5% by weight of HFC-134a; 6.5wt% +2wt% / -0.5wt% HFO-1224yd(Z). Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 8C.

[0029] The present invention also provides about 74% by weight to about 86% by weight of HFO-1234ze(E); 5% to less than 12% by weight of HFC-134a; and about 4% to about 16% by weight HFO-1224yd(Z), provided that the refrigerant has an evaporator slope of 4.5° C. or less, a GWP of less than 150, and is a Class A1 non-flammable refrigerant. Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 9.

[0030] The present invention also provides About 76% to 86% by weight of HFO-1234ze(E); 5% to less than 12% by weight of HFC-134a; and about 4% to about 14% by weight HFO-1224yd(Z), provided that the refrigerant has an evaporator slope of 4° C. or less, a GWP of less than 150, and is a Class A1 non-flammable refrigerant. Refrigerants according to this paragraph may be referred to herein for convenience as Refrigerant 10.

[0031] The present invention provides a method for providing cooling, comprising the steps of: a. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant, the refrigerant being: i. about 74% to about 86% by weight of HFO-1234ze(E); ii. less than 12% by weight of HFC-134a; iii. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant comprising: about 4% by weight to about 16% by weight of HFO-1224yd(Z); b. evaporating a refrigerant in an evaporator, wherein the gradient of the refrigerant in the evaporator is less than or equal to 4.5° C. and the refrigerant has a capacity in the system that is greater than 65% of the capacity of R-134a in the system. The method according to this paragraph may be referred to herein for convenience as Heat Transfer Method 1.

[0032] The present invention provides a method for providing cooling, comprising the steps of: a. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant as set forth in any one of refrigerants 1-10; b. evaporating a refrigerant in an evaporator, wherein the gradient of the refrigerant in the evaporator is less than or equal to 4.5° C. and the refrigerant has a capacity in the system that is greater than 65% of the capacity of R-134a in the system. The method according to this paragraph may be referred to herein for convenience as Heat Transfer Method 2.

[0033] The present invention provides a method for providing cooling, comprising the steps of: a. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant, the refrigerant being: I. 65% by weight to less than 85% by weight of HFO-1234ze(E); ii. less than 12% by weight of HFC-134a; iii. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant comprising: about 10% by weight to about 22% by weight of HFO-1336mzz(E); b. evaporating the refrigerant in the evaporator; The refrigeration system includes a high temperature heat pump system or a very high temperature air conditioning system. The method according to this paragraph may be referred to herein for convenience as Heat Transfer Method 3A.

[0034] The present invention provides a method for providing cooling, comprising the steps of: a. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant, the refrigerant being: I. 70% by weight to less than 80% by weight of HFO-1234ze(E); ii. less than 11% by weight of HFC-134a; iii. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant comprising: about 10% to about 15% by weight of HFO-1336mzz(E); b. evaporating the refrigerant in the evaporator; The refrigeration system includes a high temperature heat pump system or a very high temperature air conditioning system. The method according to this paragraph may be referred to herein for convenience as heat transfer method 3B.

[0035] The present invention provides a method for providing cooling, comprising the steps of: a. providing a vapor compression refrigeration system comprising a compressor, a condenser, an evaporator, and a refrigerant, wherein the evaporator and the refrigerant consist essentially of HDR165; b. evaporating the refrigerant in the evaporator; The refrigeration system includes a high temperature heat pump system or a very high temperature air conditioning system. The method according to this paragraph may be referred to herein for convenience as heat transfer method 3C.

[0036] As used herein, reference to a defined system or method or refrigerant, etc. by reference to a range of defined numbered systems, methods, refrigerants, etc., such as Heat Transfer Methods 1-3, includes all methods so defined, including any numbered method that includes a suffix, such as Heat Transfer Methods 1-3, which means that each of Heat Transfer Method 1, Heat Transfer Method 2, Heat Transfer Method 3A, Heat Transfer Method 3B, and Heat Transfer Method 3C are specifically included.

[0037] The present invention includes a cascade refrigeration system comprising: (a) a low stage refrigeration circuit including: (i) a low stage refrigerant, preferably having a GWP of about 150 or less; (i) a compressor; (b) an intercircuit heat exchanger in which the low stage refrigerant condenses; and (c) a high stage refrigeration circuit including a high stage refrigerant, the high stage refrigeration circuit (i) having Class 1A or Class A2L flammability, (ii) evaporating at a temperature below the low stage refrigerant condensation temperature, and (iii) comprising at least about 74% by weight HFO-1234ze(E), the high stage refrigerant evaporating in the intercircuit heat exchanger by absorbing heat from the refrigerant in the low stage refrigeration circuit. Such a cascade refrigeration circuit is described in detail below. [Brief description of the drawings]

[0038] [Figure 1] FIG. 1 is a schematic diagram of an exemplary heat transfer system useful in air conditioning, low temperature refrigeration, and medium temperature refrigeration. [Diagram 2] FIG. 1 is a schematic diagram of an exemplary heat transfer system useful in low and medium temperature refrigeration and including a steam injector. [Diagram 3] FIG. 1 is a schematic diagram of an exemplary heat transfer system useful in low and medium temperature refrigeration and including a liquid injector. [Figure 4] FIG. 1 is a schematic diagram of an exemplary heat transfer system useful in low and medium temperature refrigeration and including a suction line / liquid line heat exchanger. [Diagram 5] FIG. 1 is a schematic diagram of an exemplary heat transfer system useful in low and medium temperature refrigeration and including a steam injector and an oil separator. [Figure 6A]A typical cascade refrigeration system is shown in schematic diagram form. [Figure 6B] 1 is a schematic representation of a typical supermarket produce cooling case; [Figure 7] 1 illustrates a cascade refrigeration system useful in accordance with the present invention. [Figure 8] 1 illustrates an alternative cascade refrigeration system useful in accordance with the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] Definition: As used herein, the terms "low stage" and "high stage" are used in a relative context to designate the relative evaporation temperatures of two or more cascade refrigeration circuits. Thus, the term "low stage" in the context of a cascade refrigeration system refers to a refrigeration circuit in which the refrigerant evaporates at a lower temperature than the evaporation temperature of the refrigerant in the "high stage."

[0040] As used herein, the term "cascade refrigeration" refers to a refrigeration system having a low-stage refrigerant vapor that is cooled, and preferably condensed, at least in part by rejecting heat to a high-stage refrigerant.

[0041] The term "coefficient of performance" (hereinafter "COP") is a widely accepted measure of refrigerant performance that is particularly useful for expressing the relative thermodynamic efficiency of a refrigerant in a particular heating or cooling cycle involving evaporation or condensation of the refrigerant. In refrigeration, the term represents the ratio of the effective refrigeration or cooling capacity to the energy applied by the compressor during compression of the vapor, and thus the capacity of a given compressor to pump a quantity of heat for a given volumetric flow rate of a heat transfer fluid such as a refrigerant. In other words, given a particular compressor, a refrigerant with a higher COP will deliver more cooling or heating power. One means for estimating the COP of a refrigerant at a particular operating condition is from the thermodynamic properties of the refrigerant using standard refrigeration cycle analysis techniques (see, for example, R.C. Downing, FLUOROCARBON REFRIGERANTS HANDBOOK, Chapter 3, Prentice-Hall, 1988, which is incorporated herein by reference in its entirety).

[0042] The term "global warming potential" (hereafter "GWP") was developed to make it possible to compare the global warming impact of different gases. It compares the amount of heat trapped by a particular mass of a gas with the amount of heat trapped by a similar mass of carbon dioxide over a particular period of time. Carbon dioxide was chosen by the Intergovernmental Panel on Climate Change (IPCC) as the standard gas, giving it a GWP of 1. The higher the GWP, the more a given gas will warm the earth over that period compared to CO2. As used herein, the term GWP refers to the global warming potential of a gas, as defined by the IPCC Fifth Assessment Report, 2014. 1 and is referred to and abbreviated as AR5 herein.

[0043] The term "non-flammable" refers to a compound or composition that is determined to be non-flammable as determined in accordance with ASTM Standard E-681-2009 Standard Test Method for Concentration Limits of Flammability of Chemicals (Vapors and Gases) under the conditions set forth in ASHRAE Standard 34-2016 Designation and Safety Classification of Refrigerants, and Appendix B1 of ASHRAE Standard 34-2016, each as existing as of the filing date of this application, which are incorporated herein by reference in their entireties ("Non-Flammability Test"). Flammability is defined as the ability of a composition to ignite and / or spread a flame. Flammability is determined under this test by measuring the flame angle. Non-combustible materials would be classified as Class "1" per ASHRAE Standard 34-2016 Designation and Safety Classification of Refrigerants test protocol defining conditions and equipment, using current method ASTM E681-09 annex A1 (as each standard exists as of the filing date of this application).

[0044] As used herein, the term "evaporator glide" means 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" means the temperature at which liquid refrigerant boils to vapor at a given pressure.

[0045] As used herein, the phrase "no or low toxicity" indicates that the composition is classified as Class "A" by ASHRAE Standard 34-2016 Designation and Safety Classification of Refrigerants and is set forth in Appendix B1 of ASHRAE Standard 34-2016, as each standard exists as of the filing date of this application. 1 Myhre, G., D. Shindell, F.-M. Breon, W. Collins, J. Fuglestvedt, J. Huang, D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Roback, G. Stephens, T. Takemura, and H. Zhang, 2013: Anthropogenic and Natural Radiative Forcing. Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T. F., D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P. M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. https: / / www.ipcc.ch / pdf / assessmentreport / arS / wg1 / WG1AR5_Chapter08_FINAL.pdf(p.73-79) Materials that are nonflammable and low toxicity are classified as "A1" by ASHRAE Standard 34-2016 Designation and Safety Classification of Refrigerants and are described in Appendix B1 of ASHRAE Standard 34-2016, as each standard exists as of the filing date of this application.

[0046] The term "superheat" or simply "superheat" refers to the rise in temperature of a refrigerant at the outlet of an evaporator above the saturated vapor temperature (or dew point temperature) of the refrigerant.

[0047] As used herein, the term "E-1,3,3,3-tetrafluoropropene" means the trans isomer of HFO-1234ze and is abbreviated as HFO-1234ze(E).

[0048] As used herein, the term "Z-1-chloro-2,3,3,3-tetrafluoropropene" means the trans isomer of HFCO-1224yd and is abbreviated as HFCO-1224yd(Z).

[0049] As used herein, the term "1,1,1,2-tetrafluoroethane" is abbreviated as HFC-134a.

[0050] As used herein, the term "1,1,2,2-tetrafluoroethane" is known in the industry as the abbreviation HFC-134, and is abbreviated herein as HFC-134.

[0051] As used herein, the term "E-1,1,1,4,4,4-hexafluorobut-2-ene" means the trans isomer of HFO-1336mzz and is abbreviated as HFO-1336mzz(E).

[0052] As used herein, the term "1,1,1,2,3,3,3-heptafluoropropane" is abbreviated as HFC-227e. As used herein, the term "difluoromethane" is abbreviated as CH 2 F 2 and is abbreviated as HFC-32.

[0053] As used herein, the term "low temperature refrigeration" refers to a refrigeration system operating under or within the following conditions: (a) a condenser temperature of about 15°C to about 50°C, and (b) an evaporator temperature of about -40°C to about -15°C or less.

[0054] As used herein, the term "medium temperature refrigeration" refers to a refrigeration system utilizing one or more compressors and operating under or within the following conditions: (a) a condenser temperature of about 15°C to about 60°C, and (b) a condenser temperature of about -15°C to about 5°C.

[0055] As used herein, the term "extreme temperature air conditioning system" means a vapor compression air conditioning system in which the condensation temperature of the refrigerant is between about 55°C and about 95°C.

[0056] As used herein, the term "high temperature heat pump system" refers to a vapor compression system capable of operating in a heating mode in which the condensing temperature of the refrigerant is between about 55°C and about 95°C.

[0057] As used herein, the term "R454C" means the refrigerant designated 454C by ASHRAE and consisting of 21.5% + 2% / - 2% R-32 and 78.5% + 2% / - 2% HFC-1234yf.

[0058] As used herein, the term “R455A” is designated by ASHRAE as 455AC and is a mixture of 21.5%±2 / -1% R-32, 75.5% HFC-1234yf+2 / -2% and 3%±2 / -1% CO 2 The refrigerant used herein is a refrigerant consisting of

[0059] As used herein, the term "R471A" means the refrigerant designated 471A by ASHRAE and consisting 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.

[0060] As used herein, the term "HDR165" refers to a refrigerant consisting of 78.7% +0.5% / -2% HFC-1234ze(E), 12% +2% / -0.5% ofHFC-1336mzz(E) and 10% +2% / -0.5% ofHFC-134a.

[0061] As used herein, the term "HDR166" means a refrigerant consisting of 83.5% + 0.5% / - 2% HFC-1234ze(E), 6.5 + 2% / - 0.5% HFCO-1224yd(Z) and 10% + 2% / - 0.5% HFC-134a.

[0062] As used herein, the term "about" in reference to amounts expressed as weight percent means that the amount of the ingredient can vary in an amount of + / - 2% by weight.

[0063] Refrigerants and heat transfer compositions Applicant has unexpectedly discovered that the refrigerants of the present invention, including each of Refrigerants 1-10 described herein, can provide a series of highly advantageous properties, including: excellent heat transfer properties, including high capacity relative to HFC-134a (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 ("Ozone Depletion Potential, ODP"), relatively low evaporator gradients, 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.

[0064] A particular advantage of the refrigerants of the present invention, particularly including each of Refrigerants 1-10, is that they are non-flammable and have acceptable toxicity, i.e., each is a Class A1 refrigerant. It will be understood by those skilled in the art that refrigerant flammability may be a consideration property in certain important heat transfer applications, and that refrigerants classified as Class A1 may often be more advantageous than non-Class A1 refrigerants. Thus, there is a need in the art to provide refrigerant compositions that may be used as replacements for prior non-flammable refrigerants such as R-22, R404A, R407F, R448A, R449A, or R-134a, and have excellent heat transfer properties, acceptable toxicity, zero or near-zero ODP, and lubricant compatibility, including miscibility with POE and / or PVE lubricants, and maintain non-flammability during use 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). This desirable benefit may be achieved by the refrigerants of the present invention.

[0065] Applicants have discovered that the refrigerant compositions of the present invention, including each of Refrigerants 1-10, can achieve a difficult to achieve combination of properties, including a particularly low GWP. Thus, the compositions of the present invention have a GWP of 150 or less.

[0066] The refrigerant compositions of the present invention, which contain each of Refrigerants 1 to 10, have an ODP of zero or nearly zero. Thus, the compositions of the present invention have an ODP of 0.02 or less, more preferably zero.

[0067] It should be noted that the refrigerant compositions of the present invention, including each of Refrigerants 1-10, exhibit acceptable toxicity and preferably have an OEL greater than about 400. As one skilled in the art will recognize, non-flammable refrigerants having an OEL greater than about 400 are advantageous because they provide refrigerants that are classified as "Class A" under ASHRAE Standard 34, which is desirable.

[0068] The preferred refrigerant compositions of the present invention exhibit both acceptable toxicity and non-flammability under ASHRAE Standard 34, and are therefore Class A1 refrigerants. Applicants have discovered that the heat transfer compositions of the present invention, including heat transfer compositions comprising each of Refrigerants 1-10 described herein, can provide a highly advantageous and unexpected combination of properties, including good heat transfer characteristics, 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 entire range of operating temperatures and concentrations 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.

[0069] The heat transfer composition can consist essentially of any refrigerant of the present invention, including each of Refrigerants 1-10.

[0070] The refrigerants of the present invention may be provided in a heat transfer composition. Thus, the heat transfer composition of the present invention includes the refrigerants of the present invention, including any of the preferred refrigerant compositions disclosed herein, and in particular each of refrigerants 1-10. Preferably, the present invention relates to a heat transfer composition comprising a refrigerant, including each of refrigerants 1-10, 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 the refrigerant, or may consist of the refrigerant.

[0071] The heat transfer composition of the present invention may be comprised of any refrigerant of the present invention, including each of Refrigerants 1-10.

[0072] The heat transfer compositions of the present invention may contain other ingredients for the purpose of enhancing or providing certain functionalities to the composition. Such other ingredients may include, in addition to the refrigerants of the present invention, including each of Refrigerants 1-10, one or more of lubricants, passivators, flammability inhibitors, dyes, solubilizers, compatibilizers, stabilizers, antioxidants, corrosion inhibitors, extreme pressure additives, and antiwear additives, as well as other compounds and / or components that adjust certain properties of the heat transfer composition, and the presence of all such compounds and components is within the broad scope of the present invention.

[0073] Lubricants The heat transfer compositions of the present invention may include the refrigerants and lubricants described herein, including each of Refrigerants 1 through 10. The heat transfer composition described in this paragraph may be referred to as Heat Transfer Composition 1 for convenience.

[0074] The heat transfer compositions of the present invention may also include the refrigerants described herein, including each of Refrigerants 1-10, and polyol ester (POE) lubricants. The heat transfer composition described in this paragraph may be referred to as heat transfer composition 2 for convenience.

[0075] The heat transfer composition of the present invention may also include a refrigerant as described herein, including each of Refrigerants 1-10, and a polyvinyl ether (PVE) lubricant. The heat transfer composition described in this paragraph may be referred to as Heat Transfer Composition 3 for convenience.

[0076] The heat transfer compositions of the present invention may also include the refrigerants described herein, including each of Refrigerants 1-10, and a Polyol Alkylene Glycol (PAG) lubricant. The heat transfer composition described in this paragraph may be referred to as Heat Transfer Composition 4 for convenience.

[0077] Applicants have discovered that the heat transfer compositions of the present invention, including each of Heat Transfer Compositions 1-10, can provide the advantageous properties identified herein with respect to refrigerants, as well as exceptionally advantageous properties, including excellent refrigerant / lubricant compatibility, including miscibility with POE and / or PVE and / or PAG lubricants, over the range of operating temperatures and concentrations used in stationary air conditioning systems (including residential air conditioning, commercial air conditioning, VRF air conditioning), chillers (including air-to-water chillers), heat pump systems (including residential air-to-water heat pump systems), and commercial refrigeration (including medium temperature and low temperature refrigeration).

[0078] A lubricant consisting essentially of POE having a viscosity of about 30 to about 70 at 40° C., as measured according to ASTM D445, is referred to herein as Lubricant 1.

[0079] Commercially available POEs preferred for use in the heat transfer compositions of the present invention include neopentyl glycol dipelargonate available as Emery 2917® and Hatcol 2370®, and pentaerythritol derivatives including those sold under the trade names Emkarate RL32-3MAF and Emkarate RL68H by CPI Fluid Engineering. Emkarate RL32-3MAF and Emkarate RL68H are preferred POE lubricants having the properties identified below.

[0080] [Table 1]

[0081] Preferred heat transfer compositions include the refrigerants of the present invention, including each of Refrigerants 1-10, and Lubricant 1. The heat transfer composition described in this paragraph may be referred to as Heat Transfer Composition 5 for convenience.

[0082] A lubricant consisting essentially of POE having a viscosity of about 30 to about 70 at 40° C., measured according to ASTM D445, based on the weight of the heat transfer composition, is referred to herein as Lubricant 2.

[0083] Commercially available polyvinyl ethers having a viscosity of about 30 to about 70 at 40° C., as measured in accordance with ASTM D445, suitable for use in the heat transfer compositions of the present invention include those lubricants sold by Idemitsu under the tradenames FVC32D and FVC68D.

[0084] The lubricant of the present invention may generally comprise a PVE lubricant. In a preferred embodiment, the PVE lubricant is as a PVE according to Formula II:

[0085] [ka] In the formula, R 2 and R 3 are each independently a C1 to C10 hydrocarbon, preferably a C2 to C8 hydrocarbon, and R 1 and R 4 are each independently an alkyl, alkylene glycol, or polyoxyalkylene glycol unit, and n and m are preferably selected according to the requirements of one skilled in the art to obtain a lubricant having the desired properties, preferably n and m are selected to obtain a lubricant having a viscosity of about 30 to about 70 cSt at 40° C. as measured according to ASTM D445. The PVE lubricant according to the immediately preceding description is referred to as Lubricant 3 for convenience. Commercially available polyvinyl ethers include those lubricants sold by Idemitsu under the trade names FVC32D and FVC68D.

[0086] Preferred heat transfer compositions include a refrigerant of the present invention, including each of Refrigerants 1-10, and Lubricant 2. The heat transfer composition described in this paragraph may be conveniently referred to as Heat Transfer Composition 6A.

[0087] Preferred heat transfer compositions include a refrigerant of the present invention, including each of Refrigerants 1-10, and Lubricant 3. The heat transfer composition described in this paragraph may be conveniently referred to as Heat Transfer Composition 6B.

[0088] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1-6, wherein the lubricant is present in the heat transfer composition in an amount of from about 0.1% to about 5% by weight of the heat transfer composition. The heat transfer composition described in this paragraph may be referred to as heat transfer composition 7 for convenience.

[0089] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1-6, wherein the lubricant is present in the heat transfer composition in an amount of from about 0.1% to about 2% by weight of the heat transfer composition. The heat transfer composition described in this paragraph may be referred to as heat transfer composition 8 for convenience.

[0090] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1-6, wherein the lubricant is present in the heat transfer composition in an amount of from about 0.1% to about 1% by weight of the heat transfer composition. The heat transfer composition described in this paragraph may be referred to as heat transfer composition 9 for convenience.

[0091] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1-6, wherein the lubricant is present in the heat transfer composition in an amount of about 0.1% to about 0.5% by weight of the heat transfer composition. The heat transfer composition described in this paragraph may be referred to as heat transfer composition 10 for convenience.

[0092] The present invention includes heat transfer compositions of the present invention, including each of heat transfer compositions 1-11, 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 described in this paragraph may be referred to as heat transfer composition 11 for convenience.

[0093] Other additives not mentioned herein may also be included in light of the teachings contained herein without departing from the novel and essential characteristics of the present invention.

[0094] Additionally, a combination of surfactants and solubilizers may 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.

[0095] Methods, Uses, and Systems system The present invention includes all types of heat transfer systems comprising a refrigerant of the present invention, including each of Refrigerants 1-10, and / or comprising a heat transfer composition of the present invention, including each of Heat Transfer Compositions 1-11. The heat transfer system described in this paragraph may be referred to as Heat Transfer System 1 for convenience.

[0096] The present invention also includes low temperature refrigeration systems comprising a refrigerant of the present invention, including each of Refrigerants 1-10, and / or a heat transfer composition of the present invention, including each of Heat Transfer Compositions 1-11, and provides certain advantages in connection therewith. The heat transfer system described in this paragraph may be referred to as Heat Transfer System 2 for convenience.

[0097] The present invention also includes intermediate temperature refrigeration systems comprising a refrigerant of the present invention, including each of refrigerants 1-10, and / or a heat transfer composition of the present invention, including each of heat transfer compositions 1-11, and provides certain advantages in connection therewith. The heat transfer system described in this paragraph may be referred to as heat transfer system 3 for convenience.

[0098] The present invention also includes, and provides certain advantages in connection with, extreme temperature air conditioning systems that include a refrigerant of the present invention, which include each of refrigerants 1-10, and / or which include a heat transfer composition of the present invention, which include each of heat transfer compositions 1-11, and / or which operate according to heat transfer methods 1-3. The heat transfer system described in this paragraph may be referred to as heat transfer system 4 for convenience.

[0099] The present invention also includes high temperature heat pump systems comprising refrigerants of the present invention, and which provide certain advantages in connection therewith, which comprise each of refrigerants 1-10, and / or which comprise heat transfer compositions of the present invention, including each of heat transfer compositions 1-11, and / or which operate according to heat transfer methods 1-3. The heat transfer system described in this paragraph may be referred to for convenience as heat transfer system 5A.

[0100] The present invention also includes medium temperature refrigeration systems comprising a refrigerant of the present invention, including each of Refrigerants 1-10, and / or a heat transfer composition of the present invention, including each of Heat Transfer Compositions 1-11, and provides certain advantages in connection therewith. The heat transfer system described in this paragraph may be referred to as Heat Transfer System 5B for convenience.

[0101] The present invention also includes, and provides certain advantages in connection with, cascade refrigeration systems comprising a refrigerant of the present invention, including each of refrigerants 1-10, and / or a heat transfer composition of the present invention, including each of heat transfer compositions 1-11. The heat transfer system described in this paragraph may be referred to as heat transfer system 6 for convenience.

[0102] The present invention also provides a basic cascade refrigeration system, which comprises: (a) a low stage refrigeration circuit, a low-stage refrigerant having a GWP of about 150 or less; a low stage refrigeration circuit including a compressor; (b) an intercircuit heat exchanger in which the low-stage refrigerant is condensed; (c) a high stage refrigeration circuit including a high stage refrigerant that absorbs heat from the refrigerant in the low stage refrigeration circuit and thereby evaporates in the inter-circuit heat exchanger.

[0103] The following table defines a series of cascade refrigeration systems of the present invention that include the elements of this paragraph and additionally require the elements or limitations specified in the table below, with each such system being defined as a Cascade System (CS) of the present invention by the CS number / letter in column 1 of the table below, with it being understood that all values ​​are understood to be preceded by the word "about" unless otherwise indicated in the table. In the table below, unless the "Refrigerant Component" is specifically indicated in the table as "consisting essentially of" or "consisting of," it is also understood that the refrigerant includes the indicated refrigerant component. Similarly, unless the "Refrigerant" under the broad heading "Low Stage Requirement" is specifically indicated in the table as "consisting essentially of" or "consisting of," it is also understood that the low stage includes the indicated refrigerant. The symbol "NR" is understood to mean that the component or feature is not required (but may be present), and the symbol "NL" means that the nature of the feature is not limited by the definition in the table.

[0104] [Table 2-1]

[0105] [Table 2-2]

[0106] [Table 2-3]

[0107] The present invention includes a cascade refrigeration system including each of cascade systems 1-12 in the table above, where the low-stage refrigerant condenses in the intercircuit heat exchanger within a temperature range of about −5° C. to about −15° C. Systems according to this paragraph may be referred to herein as cascade system 13 for convenience.

[0108] The present invention includes a cascade refrigeration system including each of cascade systems 1-12 in the table above, where the high-stage refrigerant evaporates in the intercircuit heat exchanger within a temperature range of about −5° C. to about −15° C. Systems according to this paragraph may be referred to herein as cascade system 14 for convenience.

[0109] The present invention includes cascade refrigeration systems including each of cascade systems 1-12 in the table above, as well as cascade systems 13 and 14, where the low stage refrigeration circuit includes a plurality of low stage refrigeration circuits. A system according to this paragraph may be referred to herein as cascade system 15 for convenience.

[0110] The present invention includes a cascade refrigeration system including each of cascade systems 1-12 and 13-15 in the table above, where the low stage refrigeration circuit is located in an area open to the public. For convenience, a system according to this paragraph may be referred to herein as cascade system 16.

[0111] The present invention includes a cascaded refrigeration system including each of cascaded systems 1-12 and 13-16 in the table above, wherein the low stage refrigeration circuit includes a plurality of self-contained low stage refrigeration circuits, at least two of such low stage refrigeration circuits are contained in separate modular refrigeration units, each of the modular refrigeration units being located in a first area open to the public. A system according to this paragraph may be referred to herein as system 17 for convenience.

[0112] The present invention includes cascaded refrigeration systems including each of cascaded systems 1-12 and cascaded systems 13-17 in the table above, where the compressor in each of the lower stages has a horsepower rating of about 2 horsepower or less. A system according to this paragraph may be referred to herein for convenience as cascaded system 18.

[0113] The present invention includes a cascade refrigeration system including each of cascade systems 1-12 and 13-18 in the table above, the lower stage including a low temperature refrigeration circuit. A system according to this paragraph may be referred to herein as cascade system 19 for convenience.

[0114] The present invention includes a cascade refrigeration system including each of cascade systems 1-12 and 13-19 in the table above, the higher stage including a medium temperature refrigeration circuit. A system according to this paragraph may be referred to herein as cascade system 20 for convenience.

[0115] The present invention includes cascaded refrigeration systems including each of cascaded systems 1-12 and cascaded systems 13-20 in the table above, including commercial refrigeration systems. For convenience, a system according to this paragraph may be referred to herein as cascaded system 21.

[0116] The present invention also includes, and provides certain advantages in connection with, coolers (air-cooled coolers) comprising the refrigerants of the present invention, which comprise each of the refrigerants 1-10, and / or which comprise a heat transfer composition of the present invention, which comprise each of the heat transfer compositions 1-11, and / or which operate according to heat transfer methods 1-21. The heat transfer system described in this paragraph may be referred to for convenience as heat transfer system 7.

[0117] The present invention also includes and provides certain advantages in connection with heat pump systems comprising refrigerants of the present invention, including each of refrigerants 1-10, and / or heat pump systems comprising heat transfer compositions of the present invention, including each of heat transfer compositions 1-11, and / or cascaded refrigeration systems of the present invention, including each of cascaded systems 1-21. The heat transfer system described in this paragraph may be referred to as heat transfer system 8 for convenience.

[0118] The present invention also includes and provides certain advantages in connection with commercial refrigeration (including low temperature commercial refrigeration and medium temperature commercial refrigeration) comprising a refrigerant of the present invention, including each of Refrigerants 1-10, and / or a heat transfer composition of the present invention, including each of Heat Transfer Compositions 1-11, and / or a cascaded refrigeration system of the present invention, including each of Cascaded Systems 1-21. The heat transfer system described in this paragraph may be referred to as Heat Transfer System 9 for convenience.

[0119] In the case of the heat transfer system of the present invention including a compressor and compressor lubricant in the system, the system may include a loading of the refrigerant of the present invention including each of refrigerants 1-10 and lubricant including POE and PVE such that the lubricant loading in the system is about 5% to 60% by weight, or about 10% to about 60% by weight, or about 20% to about 50% by weight, or about 20% to about 40% by weight, or about 20% to about 30% by weight, or about 30% to about 50% by weight, or about 30% to about 40% by weight. As used herein, the term "lubricant loading" refers to the total weight of the lubricant contained in the system as a percentage of the total of the lubricant and refrigerant contained in the system. Such a system may also include a lubricant loading of about 5% to about 10% by weight, or about 8% by weight of the heat transfer composition.

[0120] In certain embodiments, the heat transfer composition of the present invention comprises, in a low temperature refrigeration system, any one of refrigerants 1-10, and a lubricant, as follows:

[0121] [Table 3]

[0122] The heat transfer composition for a medium temperature refrigeration system includes any one of refrigerants 1-10 and a lubricant as follows:

[0123] [Table 4]

[0124] The heat transfer composition includes any one of refrigerants 1-10 and a lubricant as follows in a retail food refrigeration system:

[0125] [Table 5]

[0126] The heat transfer composition for use in a transport refrigeration system includes any one of refrigerants 1-10 and a lubricant as follows:

[0127] [Table 6]

[0128] Exemplary Heat Transfer Systems As will be described in detail below, a preferred system of the present invention includes a compressor, a condenser, an expansion device, and an evaporator, all in fluid communication using piping, valves, and control systems so that the refrigerant and associated components of the heat transfer composition may flow through the system in a well-known manner to complete a refrigeration cycle. An exemplary schematic diagram of such a basic system is shown in FIG. 1. In particular, the system shown generally in FIG. 1 shows a compressor 10, which provides compressed refrigerant vapor to a condenser 20. The compressed refrigerant vapor condenses to produce liquid refrigerant, which is then directed to an expansion device 40 which produces a refrigerant at a reduced temperature and pressure, which is then provided to an evaporator 50. Within the evaporator 50, the liquid refrigerant absorbs heat from a body or fluid being cooled to produce a refrigerant vapor, which is then provided to the suction line of the compressor.

[0129] The refrigeration system illustrated in Figure 2 is the same as that described above in connection with Figure 1, except that it includes a vapor injection system including a heat exchanger 30 and a bypass expansion valve 25. The bypass expansion device 25 provides liquid refrigerant to the heat exchanger 30 at reduced pressure, and therefore at a low temperature, by diverting a portion of the refrigerant flow at the condenser outlet through the device. This relatively cool liquid refrigerant then exchanges heat with the relatively hotter remaining liquid from the condenser. This action produces subcooled liquid in the main expansion device 40 and the evaporator 50, and relatively cool refrigerant vapor is returned to the compressor 10. Injecting cooled refrigerant vapor into the suction side of the compressor in this manner serves to maintain the compressor discharge temperature within acceptable limits, which may be particularly advantageous in low temperature systems utilizing high compression ratios.

[0130] The refrigeration system illustrated in Figure 3 is the same as that described above in connection with Figure 1, 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 exiting the condenser to a liquid injection port in the compressor, preferably compressor 10. Injecting liquid refrigerant into the suction side of the compressor in this manner serves to maintain the compressor discharge temperature within acceptable limits, which may be particularly advantageous in low temperature systems utilizing high compression ratios.

[0131] The refrigeration system illustrated in Figure 4 is the same as that described above in connection with Figure 1, except that it includes a liquid line / suction line heat exchanger 35. Valve 25 diverts some, and optionally all, of the refrigerant flow from the condenser outlet to the liquid line / suction line heat exchanger 35, where 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.

[0132] The refrigeration system illustrated in Figure 5 is the same as that described above in connection with Figure 1, 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 typically carried in the compressor discharge refrigerant vapor, and the oil separator is included to provide a means to separate the lubricant liquid from the refrigerant vapor, with the resulting refrigerant vapor having a reduced lubricant oil content proceeding to a condenser inlet, and the liquid lubricant is then returned to a lubricant reservoir, such as a lubricant receiver, for use in lubricating the compressor. In a preferred embodiment, the oil separator includes a sealing material as described herein, preferably in the form of a filter or solid core.

[0133] Those skilled in the art will appreciate that the different equipment / configuration options shown separately in each of Figures 2-5 may be combined and used together as deemed advantageous in any application involving a cascade refrigeration system, although the preferred embodiment of the cascade refrigeration system is described above in connection with Figures 6A and 6B and below in connection with Figures 7-9.

[0134] Cascaded System The present invention also includes a cascade refrigeration system including each of cascade systems 1-21, wherein the heat exchanger (iii) is a heat exchanger in which the higher stage refrigerant evaporates within the heat exchanger by absorbing heat from the lower stage.

[0135] The present invention also includes cascaded refrigeration systems including each of cascaded systems 1-21, each comprising a plurality of low temperature refrigeration circuits, each low temperature refrigeration circuit comprising 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 a flammable low temperature refrigerant consisting of HFO-1234yf, R454C, R455A, propane, or combinations thereof. As used herein, reference to a numbered system or group of numbered systems defined herein means each such numbered system, including each numbered system in the group, and also including numbered systems with a suffix. For example, reference to cascaded system 1 includes reference to each of cascaded systems 1A, 1B, and 1C.

[0136] The invention also includes a cascade refrigeration system including each of cascade systems 1-21, including a plurality of low temperature refrigeration circuits, each low temperature refrigeration circuit including a combustible low temperature refrigerant including at least about 75% by weight, or at least 95% by weight, or at least 99% by weight HFO-1234yf, and the heat exchanger is a heat exchanger in which the medium temperature refrigerant evaporates within the heat exchanger by absorbing heat from the low temperature refrigerant.

[0137] As used herein, the term "low temperature refrigeration unit" means an at least partially closed or closeable structure capable of providing cooling within at least a portion of the structure and structurally distinct from the structure surrounding or containing the high stage refrigeration circuit. In accordance with and consistent with this meaning, the preferred low stage refrigeration circuit and the low temperature refrigeration circuit are referred to herein as "self-contained" when contained within such a first (preferably low temperature) cooling unit, in accordance with the meaning described herein.

[0138] In a preferred embodiment, each low-stage cooling unit including a unit corresponding to a low stage in each of the cascade systems 1 to 21 may be arranged in a first area. The first area may be a shop floor. That is, each first refrigeration circuit (preferably a low-temperature refrigeration circuit) may also be arranged in a first area such as a floor of a store or supermarket that is accessible to the general public.

[0139] Each refrigeration unit comprising each of the cascade systems 1-11 may consist of a space to be cooled and / or an object contained within the space, preferably the space being within the refrigeration unit. Each evaporator may be arranged to cool its respective space / object, preferably by cooling the air within the space to be cooled.

[0140] As described above, the high-stage refrigeration circuit of the present invention, including the high stage in each of the cascade systems 1-11, may have components of the high-stage refrigeration circuit extending between the low-stage cooling unit (preferably the low-temperature refrigeration unit) and a second region. The second region may be, for example, a machine room housing a substantial portion of the components of the high-stage refrigeration circuit.

[0141] The high-stage refrigeration circuit of the present invention included in each of the cascade systems 1-21 can be extended to a second and a third region. The third region can be an area outside the building or buildings in which the first cooling unit and the second region are located. This allows for the use of ambient cooling.

[0142] Unless otherwise indicated herein for a particular embodiment, each refrigerant in the low stage refrigeration circuit may be different or the same as the other refrigerants in the low stage refrigeration circuit, and each may also be different or the same as the refrigerant in the high stage refrigeration circuit.

[0143] The high stage refrigeration circuit may be quite long and extend between different areas of a building, for example, between the factory floor (where the refrigeration units are located) and the machine room. As a result, in such embodiments, it may be unsafe to have a flammable refrigerant in the high stage refrigeration circuit, as both the risk of a leak and the severity of a potential leak are increased since the high stage refrigeration circuit spans a larger area, thus exposing more people and / or structures to the risk of fire.

[0144] Each low-stage refrigeration circuit included in the cascade systems 1-21 may comprise at least one fluid expansion device. The at least one fluid expansion device may be a capillary tube or an orifice tube. This is enabled by the conditions imposed on each first refrigeration circuit by its corresponding cooling unit being relatively constant. This means that simpler flow control devices such as capillary tubes and orifice tubes may be, and preferably are, used to serve in the first refrigeration circuit.

[0145] The high-stage 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 position.

[0146] One embodiment of a cascade refrigeration system according to the present invention is illustrated diagrammatically in FIG. 7 and described in detail below.

[0147] FIG. 7 illustrates a cascade refrigeration system 200. More specifically, FIG. 7 illustrates the refrigeration system 200 having three low stage refrigeration circuits 220a, 220b, and 220c. Each of the low stage refrigeration circuits 220a, 220b, and 220c includes 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 a circuit are illustrated by a single icon, it will be understood that the compressors, evaporators, heat exchangers, expansion valves, etc. may each include multiple such units. In each circuit 220a, 220b, and 220c, the evaporators 223, compressors 221, heat exchangers 230, and expansion valves 222 are connected in series with each other in the order listed. Each of the low stage refrigeration circuits 220a, 220b, and 220c is contained within a separate respective cooling unit (not shown). In this embodiment, each of the three refrigeration units is preferably a refrigerator unit that houses a respective low temperature refrigeration circuit. In this manner, each cooling unit includes a built-in, dedicated low temperature refrigeration circuit. The refrigeration units (not shown), and thus the low temperature refrigeration circuits 220a, 220b, 220c, may be located, for example, on the sales floor 242 of a supermarket.

[0148] 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 thereof. As one skilled in the art would understand, 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 low stage refrigeration circuits 220a, 220b, 220c, but in a preferred embodiment, each of the multiple low stage circuits contains CO2, propane, HFO-1234yf, R454C, R455A, or a combination of two or more thereof.

[0149] The refrigeration system 200 also has a high-stage refrigeration circuit 210. The high-stage 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 compressors, condensers, fluid receivers, etc. in the high-stage circuit are illustrated by a single icon, it will be understood that the compressors, evaporators, heat exchangers, expansion valves, etc. may each include multiple such units. The high-stage refrigeration circuit 210 also has four parallel-connected branches, namely, three medium-temperature cooling branches 217a, 217b, and 217c that are not in heat transfer communication with the low stage, 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 valves 218 and evaporators 219 are connected in series in a given order between the fluid receiver 214 and the condenser 211. In a preferred embodiment, the high stage circuit 220, which includes the low temperature cooling branch 216, has an expansion valve 212 and interfaces in the form of inlet and outlet piping, conduits, valves, etc. (collectively designated as 260a, 260b, and 260c, respectively) that provide high stage refrigerant liquid to, and therefrom high stage refrigerant vapor to, each of the inter-circuit heat exchangers 230a, 230b, and 230c, which are disposed within the cooling unit 220, as shown in the preferred embodiment. The cryogenic cooling branch 216 interfaces with each of the intercircuit heat exchangers 230a, 230b, 230c at a respective circuit interface location 231a, 231b, 231c. Each of the circuit interface locations 231a, 231b, 231c is arranged in series-parallel combination with each of the other circuit interface locations 231a, 231b, 231c.

[0150] High stage refrigeration circuit 210 has components extending between the sale floor 242, the machine room 241, and the roof 140. The cold branch 216 and the medium temperature branches 218a, 218b, 218c of the medium temperature refrigeration circuit 210 are preferably located on the sale floor 242. The compressor 211 and fluid receiver 214 are preferably located in the machine room 241. The condenser 213 is preferably located in a location where it can be readily exposed to ambient conditions, such as on the roof 240.

[0151] In this example, the refrigerant in the high stage refrigeration circuit 210 comprises, consists essentially of, or consists of a refrigerant comprising at least about 74% by weight HFO-1234ze and having Class 1A or A2L flammability. The present invention includes a cascade type system in which the refrigerant in the high stage refrigeration circuit 210 comprises, consists essentially of, or consists of HFO-1234ze(E), HDR165 and / or HDR166. Further advantageously, the present blends have excellent heat transfer performance properties along with a low GWP making it an environmentally friendly solution, as illustrated below in the examples herein.

[0152] Use of the preferred embodiment illustrated in FIG. 7 can be summarized as follows. Each of the low stage refrigeration circuits 220a, 220b, 220c absorbs heat via their evaporators 223 to provide low temperature refrigeration to a space to be cooled (not shown); The high stage refrigeration circuit 210 absorbs heat from each of the inter-circuit heat exchangers 230a, 230b, 230c via the branch 216 to cool and condense the low stage refrigerant vapor from the respective compressors in each of the low stage circuits 220a, 220b, 220c; The high stage refrigeration circuit 210 absorbs heat in each of the evaporators 219 to provide medium temperature cooling to a space to be cooled (not shown); Heat is removed from the refrigerant in the high stage refrigeration circuit 210 in an air-cooled chiller 213 .

[0153] 7, several beneficial results can be achieved, particularly since each refrigeration circuit 230 is self-contained within the corresponding cooling unit. For example, installation and removal of the cooling units and the overall cascade refrigeration system 200 is simplified, since the cooling units with built-in self-contained refrigeration circuits 220a, 220b, 220c can be easily connected and disconnected from the high stage refrigeration circuit 210 without requiring modifications to the refrigeration circuits 220, 220b, 220c. In other words, the cooling units can simply be "plugged" into the high stage refrigeration circuit 210.

[0154] Another advantage is that each cooling unit, including the corresponding first refrigeration circuit 220a, 220b, 220c, may undergo default factory testing before being installed in the live refrigeration system 200. This reduces the chance of defects, which may include potentially harmful refrigerant leaks. Thus, reduced leak rates may be realized.

[0155] Another advantage of the preferred embodiment is the provision of an intercircuit heat exchanger in the systems of the present invention, including each of the cascaded systems 1-21, which provides improved heat transfer between the lower and higher stages, thus improving the overall refrigeration system efficiency.

[0156] In a preferred embodiment including each of the cascade systems 1 to 21, the present invention also includes a cascade refrigeration system, the cascade refrigeration system including a plurality of low temperature refrigeration circuits, each of which includes a low temperature refrigeration circuit having a GWP of about 150 or less, specifically, at least about 75% by weight of R1234yf including R-454C and / or R455A, and includes a compressor having an operating power of about 3.5 kilowatts or less, and the low temperature refrigerant is refrigerated at a temperature range of about -5°C to about -15°C. and a medium temperature refrigeration circuit comprising an inter-circuit heat exchanger for condensing a medium temperature refrigerant, the medium temperature refrigerant comprising, consisting essentially of, or consisting of at least about 74% by weight of HFO-1234ze(E), particularly including HDR165 and / or HDR166, and an evaporator in which the medium temperature refrigerant evaporates at a temperature below the low temperature refrigerant condensation temperature and in the range of about -5°C to about -15°C, the medium temperature refrigerant evaporating in the heat exchanger by absorbing heat from the low temperature refrigerant.

[0157] In a preferred embodiment including each of the cascade systems 1-21, the present invention also includes a cascade refrigeration system comprising: a plurality of low temperature refrigeration circuits, each of which has a GWP of about 150 or less, specifically comprising at least about 75% by weight of R1234yf, including R-454C and R-455A; a compressor having a compressor rating of 2 horsepower or less; and an inter-circuit heat exchanger in which the low temperature refrigerant condenses in a temperature range of about -5°C to about -15°C. a medium temperature refrigeration circuit comprising a medium temperature refrigerant, the medium temperature refrigerant comprising, consisting essentially of, or consisting of at least about 74% by weight of HFO-1234ze(E), specifically including HDR165 and / or HDR-166; and an evaporator in which the medium temperature refrigerant evaporates at a temperature in the range of about -5°C to about -15°C below the low temperature refrigerant condensation temperature, wherein the medium temperature refrigerant evaporates in the heat exchanger by absorbing heat from the low temperature refrigerant.

[0158] Cascade Refrigeration Systems - Alternatives As will be understood by one of ordinary skill in the art in view of the teachings contained herein, in accordance with the present invention including each of the cascaded systems 1-21, there may be any number of low stage refrigeration circuits 220. In particular, there may be as many low stage refrigeration circuits 220 as there are cooling units being cooled. Thus, the high stage refrigeration circuit 210 may interact with any number of low stage refrigeration circuits 220, and vice versa.

[0159] As will be apparent to one of ordinary skill in the art in view of the teachings contained herein, there may be any number and arrangement of high stage circuit branches 217 and evaporators 218 according to the present invention including each of the cascaded systems 1-21. In an alternative configuration according to the present invention including each of the cascaded systems 1-21, each low stage circuit 220 may be disposed completely in parallel with each other low stage circuit 220. An example of such a configuration is shown in FIG. 8. FIG. 8 shows a system 300 in which each circuit interface location present in the intercircuit heat exchangers 231a, 231b, 231c is disposed completely in parallel with each circuit interface location. The components of system 300 are otherwise the same as those of system 200 (described with reference to FIG. 7), and the components of system 300 function in substantially the same manner as system 200, although it will be understood that the performance of the overall system and other important features of the overall system may be significantly affected by this change in configuration.

[0160] Usefully, only a given portion of the refrigerant from the high-stage refrigeration circuit 210 passes through one inter-circuit heat exchanger 230 before returning to the compressor 211. This configuration therefore ensures that each of the heat exchangers 230 receives the high-stage refrigerant at approximately the same temperature, as no heat exchanger receives a portion of the refrigerant that has been preheated by passing through an upstream heat exchanger, as would be the case in a series configuration.

[0161] As will be apparent to those skilled in the art in view of the teachings contained herein, the present invention, including each of the cascaded systems 1-21, enables and indeed contemplates one and many other arrangements of the circuit interface locations 231a, 231b, 231c with respect to the high stage refrigeration circuit 210.

[0162] As will be apparent to one of ordinary skill in the art in view of the teachings contained herein, the preferred modular design of the lower stage circuits of the preferred embodiments of the present invention, including each of the cascaded systems 1-21, allows for the use of non-flammable, low pressure refrigerants having relatively low GWP.

[0163] Intake Line Heat Exchanger A further possible modification of any of the systems forming part of this disclosure, including each of the cascaded systems 1-21, is that any number of the built-in refrigeration circuits may include a Suction Line Heat Exchanger (SLHX). More specifically, any of the low stage refrigeration circuits 220a, 220b, 220c of system 200, including each of the cascaded systems 1-21, may include an SLHX, but any of the low stage refrigeration circuits 420a, 420b may include an SLHX.

[0164] The use of SLX reduces the temperature of the refrigerant entering the expansion valve 730. This additional subcooling translates into a lower inlet quality at the evaporator 740 following the expansion valve 730. This increases the enthalpy difference, thus improving the ability of the refrigerant to absorb heat in the stages of the evaporator 740. Thus, the performance of the evaporator 740 is improved.

[0165] In summary, it is necessary to consider both the primary and secondary effects of improved evaporator capacity, as well as improved compressor power requirements, to determine whether introducing a SLHX will provide an overall beneficial effect. In general, the use of a SLHX in accordance with the present invention, including each of the cascaded systems 1-21, and particularly such systems 200 and 300 herein, provides an overall positive and unexpected beneficial effect.

[0166] method Air Conditioning System The present invention also relates to air conditioning systems comprising a refrigerant of the present invention, including each of Refrigerants 1-10, or a heat transfer composition comprising a refrigerant of the present invention, including each of Heat Transfer Compositions 1-1. The present invention also provides a method of air conditioning using an air conditioning system, comprising the steps of (a) evaporating a refrigerant composition of the present invention, including each of Refrigerants 1-10, in the vicinity of a fluid of a body to be cooled, and (b) condensing the refrigerant. The air may be conditioned either directly or indirectly by a refrigerant of the present invention, including each of Refrigerants 1-10. Examples of air conditioning systems include chillers, residential, industrial, commercial, and mobile air conditioning, including air conditioning of road vehicles such as automobiles, trucks, and buses, and air conditioning of boats and trains.

[0167] Preferred refrigeration systems of the present invention include chillers containing the refrigerants of the present invention, particularly including each of Refrigerants 1-10.

[0168] Preferred refrigeration systems of the present invention include residential air conditioning systems containing the refrigerants of the present invention, particularly including each of Refrigerants 1-10.

[0169] Preferred refrigeration systems of the present invention include industrial air conditioning systems containing the refrigerants of the present invention, particularly including each of Refrigerants 1-10.

[0170] Preferred refrigeration systems of the present invention include commercial air conditioning systems containing the refrigerants of the present invention, particularly including each of Refrigerants 1-10.

[0171] Preferred refrigeration systems of the present invention include mobile air conditioning systems containing the refrigerants of the present invention, particularly including each of Refrigerants 1-10.

[0172] It will be understood that any of the above refrigeration, air conditioning, or heat pump systems using a refrigerant of the present invention, including each of Refrigerants 1-10, or a heat transfer composition comprising a refrigerant of the present invention, including each of Heat Transfer Compositions 1-11, may include a suction line / liquid line heat exchanger (SL-LL HX).

[0173] Organic Rankine Cycle System The refrigerant compositions of the present invention, including each of refrigerants 1-10, or heat transfer compositions of the present invention, including each of heat transfer compositions 1-11, may be used in an Organic Rankine Cycle (ORC). In the context of ORC, the refrigerants used in these systems may also be classified as "working fluids". Rankine cycle systems are well known to be a simple and reliable means for converting thermal energy into mechanical shaft power.

[0174] In industrial environments, it may be possible to use flammable working fluids such as toluene and pentane, especially when the industrial environment already has large amounts of flammable materials in operation or stored on-site. However, there is a need to use non-flammable and / or non-toxic refrigerants as working fluids when the risks associated with the use of flammable and / or toxic working fluids are not acceptable, such as power generation in populated areas or near buildings. There is also a drive within the industry to make these materials environmentally acceptable from a GWP perspective.

[0175] The 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 and vaporizes it into saturated or superheated steam. This vapor expands through a turbine and the waste heat energy is converted to mechanical energy. The gas-phase working fluid is then condensed to a liquid and pumped back to the boiler to repeat the heat extraction cycle. Thus, the present invention relates to the use of the refrigerants of the present invention, including each of refrigerants 1-10, or heat transfer compositions comprising the refrigerants of the present invention, including each of heat transfer compositions 1-11, in an organic Rankine cycle.

[0176] Thus, the present invention provides a process for converting thermal energy to mechanical energy in a Rankine cycle, the method comprising: i) vaporizing a working fluid at a heat source and expanding the resulting vapor, or vaporizing a working fluid at a heat source and expanding the resulting vapor, and then ii) cooling the working fluid at a heat sink to condense the vapor, wherein the working fluid is a refrigerant-containing heat transfer composition of the present invention, including each of the refrigerants or heat transfer compositions of the present invention, including each of Refrigerants 1-11. The mechanical work may be transmitted to an electrical device, such as a generator, to produce electrical power.

[0177] The heat source may be provided by a thermal energy source selected from industrial waste heat, solar energy, geothermal hot water, low pressure steam, distributed power generation equipment utilizing fuel cells, internal combustion engines, or prime movers. Preferably, the low pressure steam is low pressure geothermal steam or is provided by a fossil fuel powered power plant.

[0178] It will be appreciated that heat source temperatures can vary widely, such as, for example, from about 90° C. to over 800° C., but for certain combustion gases and some fuel cells, can depend on a myriad of factors, such as geography, time of year, etc. For example, sources such as wastewater or low pressure steam from plastic manufacturing plants, and / or chemical or other industrial plants, oil refineries, etc., as well as systems based on geothermal sources, can have source temperatures of about 100° C. or less, in some cases as low as about 90° C., or even as low as about 80° C. Gaseous heat sources, such as exhaust gases from a combustion process or any heat source where subsequent processing to remove particulates and / or corrosive species occurs at low temperatures, can also have source temperatures of about 130° C. or less, about 120° C. or less, about 100° C. or less, in some cases as low as about 90° C., or even as low as about 80° C.

[0179] electronic cooling Refrigerant compositions of the present invention, including any one of Refrigerants 1-11, may be used in connection with systems and methods for electronic cooling, such as cooling chips, electronic boards, batteries (including batteries used in automobiles, trucks, buses, and other electronic transportation vehicles), computers, and the like. EXAMPLES

[0180] In the following examples, refrigerant compositions according to the invention are identified in Table E below as compositions E1-E7. Each of the refrigerants was tested and evaluated by the applicant and found to be non-flammable, i.e., a Class A1 refrigerant, but each of E1-E7 was also subjected to a thermodynamic analysis to determine its ability to match the operating characteristics of R-134a in various refrigeration systems. The analysis was performed using experimental data collected on the properties of various binary and ternary pairs of components used in the refrigerants. The composition of each pair was varied over a range of relative percentages in the experimental evaluation, and the blend parameters of each pair were regressed to the experimentally obtained data. The examples used well-known vapor / liquid equilibrium behavior data available in the National Institute of Science and Technology (NIST) Reference Fluid Thermodynamic and Transport Properties Database software (Refprop 9.1 NIST Standard Database 23 from April 2016). Each blend was also evaluated to determine its classification for flammability as described above.

[0181] [Table 7]

[0182] As can be seen from Table E1A above, each of the refrigerants E1 to E7 according to the present invention achieves a GWP value (AR5) of less than 150 while at the same time achieving a flammability class A1.

[0183] For comparison, five refrigerant blends outside the scope of the refrigerants of this invention were also analyzed to determine their GWP, each 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 shown in Table C below.

[0184] [Table 8]

[0185] In contrast to the refrigerants of the present invention, none of the refrigerants C1 to C5 can achieve a GWP of less than 150.

[0186] Examples 1A-1D: Performance in a medium temperature refrigeration system Refrigerants E1-E7 were performance tested in a medium temperature refrigeration system without a suction line / liquid line heat exchanger (SL / LL HX). This analysis was performed to evaluate the efficiency (COP) of refrigerants E1-E7 in this system at different effectiveness levels of SL-LL HX under the following conditions: (d) The operating conditions used for all tests were as follows: Condensation temperature = 45℃ ● Condensation temperature - ambient temperature = 10℃ Condenser subcooling = 0.0°C (system with a receiver) Evaporation temperature = -8℃ ● Evaporator superheat = 5.5℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 10℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75%

[0187] The results are reported in Table E1A below.

[0188] [Table 9]

[0189] As evidenced by the data reported in Table E1A, the refrigerants of the present invention, including E1-E7 and Refrigerants 1-10, can achieve a GWP(AR5) of less than 150, but with Class A1 flammability, while also achieving efficiencies very closely comparable to R134a, capacities greater than 65%, and evaporator slopes of 4.5 or less. This is an unexpected and highly desirable result. A particularly unexpected and highly desirable performance is achieved by the refrigerants of the present invention, represented by E1-E5, in that these refrigerants achieve the following highly desirable, but very difficult to achieve, combination of properties: a. GWP(AR5)<150 b. Class A1 flammability c.100 COP d.65% or more capacity e. Evaporator gradient of 3.5°C or less Particularly advantageous and unexpected results are achieved with refrigerants in the range represented by E1-E3, especially E2A and E2B, due to the ability to achieve the following combination of properties: a. GWP(AR5)<150 b. Class A1 flammability c.100 COP d. 70% or more capacity e. Evaporator gradient of 2.5°C or less

[0190] Similar results are achieved as shown above when suction line / liquid line heat exchangers are included in the system at 35%, 55% and 75% efficiency, as reported in Tables E1B, E1C and E1D below.

[0191] [Table 10]

[0192] [Table 11]

[0193] [Table 12]

[0194] Example C1A - Performance of Medium Temperature Refrigeration System (e) Examples E1A-E1D are repeated, except that refrigerants C4 and C5 are tested for comparison in terms of GWP, capacity, COP, and slope. As reported in Tables C1A-C1D below, C4 and C5 each have a GWP of over 150, but the C4 and C5 refrigerants were selected for comparison because they had the lowest GWP of the refrigerants in Table C. Tables C1A-C1D below also show results in each case for refrigerants E2B and E4 for comparison, as representative of the performance of the refrigerants of the present invention.

[0195] [Table 13]

[0196] As can be seen from Table C1A, the C4 and C5 refrigerants (consisting of HFO-1234ze(E), 1224yd(Z), and HFC-134) are unable to achieve a GWP below 150, or an evaporator slope below 4.5° C., or a capacity above 65%. This illustrates some of the highly unexpected and advantageous results of the refrigerants of the present invention. Similar unexpected advantages are achieved in systems having suction line / liquid line heat exchangers, as shown in Tables C1B-C1D below.

[0197] [Table 14]

[0198] [Table 15]

[0199] [Table 16]

[0200] Example 2: Performance of a low temperature refrigeration system with and without an air line / liquid line heat exchanger Performance tests were conducted for refrigerants E1-E7 in a low temperature refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX). The analysis was conducted to evaluate the efficiency (COP) of refrigerants E1-E7 in this system at different effectiveness levels of SL-LL HX under the following conditions: The operating conditions were as follows: Condensation temperature = 45℃ ● Condensation temperature - ambient temperature = 10℃ Condenser subcooling = 0.0°C (system with a receiver) Evaporation temperature = -35℃, corresponding internal temperature = -25℃ ● Evaporator superheat = 5.5℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 10℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75% The results are reported in Table E2 below.

[0201] [Table 17]

[0202] Table 3 shows the performance of refrigerants in a low temperature refrigeration system. It will be appreciated that the results in the column with "0%" efficiency of SL-LL HX represent a system without SL-LL HX, and that refrigerants E1-E7 show improved performance in terms of efficiency (COP) over R134a when employing a SL / LL heat exchanger, and compositions E1-E5 show superior performance when all relevant performance factors are considered, for example as described in relation to Example 1.

[0203] Example 3: Performance in a Medium Temperature Refrigeration System with Two-Stage Vapor Injected Compression Performance tests were carried out on refrigerants E1-E7 in a medium temperature refrigeration system with two-stage vapor injection compression. This analysis was carried out to evaluate the efficiency (COP) of refrigerants E1-E7 in this system under the following conditions. The operating conditions were as follows: Condensation temperature = 45℃ ● Condensation temperature - ambient temperature = 10℃ Condenser subcooling = 5.0℃ Evaporation temperature = -8℃, corresponding internal temperature = 1.7℃ ● Evaporator superheat = 5.5℃ ● Compressor isentropic efficiency = 70% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 10℃ ● Steam injection heat exchanger (HX) efficiency: 15%, 35%, 55%, 75% The results are reported in Table E3 below.

[0204] [Table 18]

[0205] Table E3 shows the performance of the refrigerants in a medium temperature refrigeration system. Compositions E1 to E7 show improved performance in terms of efficiency (COP) over R134a in two-stage compression with vapour injection, and compositions E1 to E5 show excellent performance when all relevant performance factors are taken into account, for example as explained in relation to Example 1.

[0206] Example 4: Performance of the refrigerant of the present invention in a cascade refrigeration system Cascade systems are typically used in applications where there is a large temperature difference between the ambient temperature and the inside temperature (e.g., about 50-80°C, such as about 60-70°C) (e.g., between the air side of the condenser in the high stage and the air side of the evaporator in the low stage). For example, cascade systems may be used to freeze products in supermarkets. In this example, exemplary compositions E1-E7 of the present invention were tested as refrigerants in the high stage of a cascade refrigeration system, and each of the following compositions was used in the low stage: CO2, propane, R1234yf, R454C, and R455AC. In Tables E4A-E4E below, performance is compared to R-134a as the baseline refrigerant in both the high and low stages. The operating conditions were as follows: Condensation temperature = 45℃ ● High stage condensation temperature - ambient temperature = 10℃ - Subcooling of high stage condenser = 0.0℃ (system with receiver) Evaporation temperature = -30℃, corresponding internal temperature = -18℃ ● Low-stage evaporator superheat = 3.3℃ High and low stage compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise at low stage of intake line = 15℃ ● Temperature rise at high stage of intake line = 10℃ ● Intermediate heat exchanger with indicated low stage refrigerant condensation temperatures = 0C, 5℃ and 10℃ ● Intermediate heat exchanger superheat = 3.3℃ ● Temperature difference at intermediate heat exchanger = 8℃ Performance results are reported in Tables E4A through E4E.

[0207] [Table 19]

[0208] [Table 20]

[0209] [Table 21]

[0210] [Table 22]

[0211] [Table 23]

[0212] Tables E4A to E4E show the performance of the refrigerants of the present invention in the high stages of a cascade refrigeration system, along with various refrigerants in the low stages. These tables show that refrigerants E1 to E7 match the efficiency of R134a for different condensing temperatures in the low stage cycle, while compositions E1 to E5 show exceptional performance when all relevant performance factors are considered, for example as described in connection with Example 1.

[0213] Example 5: Performance in a vending machine with and without an air line / liquid line heat exchanger Performance testing was performed on refrigerants E1-E7 in a vending machine refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX). This analysis was performed to evaluate the efficiency (COP) of refrigerants E1-E7 in this system at different effectiveness levels of SL-LL HX under the following conditions: Operating conditions: Condensation temperature = 45℃ ● Condensation temperature - ambient temperature = 10℃ Condenser subcooling = 5.5℃ Evaporation temperature = -8℃ ● Evaporator superheat = 3.5℃ ● Compressor isentropic efficiency = 60% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 5℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75% The performance results are reported in Table E5 below.

[0214] [Table 24]

[0215] Table E5 shows the performance of refrigerants E1-E7 in vending machine systems with and without SL / LL HX. The results in the column with SL-LL HX efficiency of "0%" represent systems without SL-LL HX, and it will be appreciated that refrigerants E1-E7 show improved performance in terms of efficiency (COP) over R134a when employing a SL / LL heat exchanger, and compositions E1-E5 show superior performance when all relevant performance factors are considered, for example as described in relation to Example 1.

[0216] Example 6: Performance of an air source heat pump water heater In an air-source heat pump hot water heater system, a performance test was conducted for refrigerants E1 to E7. This analysis was carried out to evaluate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions. The operating conditions were as follows: Condensation temperature = 55℃ ● Water inlet temperature = 45℃, water outlet temperature = 50℃ Condenser subcooling = 5.0℃ ● Evaporation temperature = -5℃, corresponding ambient temperature = 10℃ ● Evaporator superheat = 3.5℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 5℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75% The performance results are reported in Table E6 below.

[0217] [Table 25]

[0218] Table E6 shows the performance of refrigerants E1 to E7 in a heat pump hot water heater. Refrigerants E1 to E6 show similar efficiency to R134a, while compositions E1 to E5 show exceptional performance when all relevant performance factors are considered, for example as explained in relation to Example 1. Refrigerants E1 to E7 show lower discharge temperatures than R134a, indicating better compressor reliability.

[0219] Example 7: Performance of an air-source heat pump hot water heater with an air-line / liquid-line heat exchanger Performance tests were conducted for refrigerants E1-E7 in an air source heat pump hot water heater system with and without a suction line / liquid line heat exchanger (SL / LL HX). The analysis was conducted to evaluate the efficiency (COP) of refrigerants E1-E7 in this system at different effectiveness levels of SL-LL HX under the following conditions: The operating conditions were as follows: Condensation temperature = 55℃ ● Water inlet temperature = 45℃, water outlet temperature = 50℃ Condenser subcooling = 5.0℃ ● Evaporation temperature = -5℃, corresponding ambient temperature = 10℃ ● Evaporator superheat = 3.5℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 5℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75% The performance results are reported in Table E7 below.

[0220] [Table 26]

[0221] Table E7 shows the performance of the refrigerants in a heat pump hot water heater with SL / LL HX. Refrigerants E1-E7 show higher efficiency than R134a when a SL / LL heat exchanger is employed, and compositions E1-E5 show superior performance when all relevant performance factors are considered, for example as described in connection with Example 1. Refrigerants E1-E7 show lower discharge temperatures than R134a, indicating better compressor reliability.

[0222] Example 8: Performance in mobile air conditioning systems (buses, trains, cars) Performance tests were conducted on refrigerants E1-E6 in a mobile air conditioning system under various condenser temperature conditions. This analysis was carried out to evaluate the efficiency (COP) of refrigerants E1-E6 in this system under the following operating conditions: ● Condensation temperature = 45℃~75℃ Condenser subcooling = 5.0℃ Evaporation temperature = 4°C, corresponding indoor temperature = 35°C Evaporator superheat = 5.0℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 0℃ The performance results are reported in Table E8 below.

[0223] [Table 27]

[0224] In table E8, refrigerants E1 to E7 show similar efficiency to R134a over a range of condensation temperatures corresponding to different ambient temperatures, while compositions E1 to E5 show superior performance when all relevant performance factors are taken into account, for example as explained in relation to example 1.

[0225] Example 9: Performance of the refrigerant of the present invention in a micro-cascade refrigeration system Micro-cascade systems include several small low temperature self-contained refrigeration systems that combine conventional medium temperature DX refrigeration systems with or without a suction line liquid line heat exchanger (SLHX) to operate with refrigerants E1-E7 in the high stages of the micro-cascade and the following refrigerants in the low stages: 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 type systems are disclosed in U.S. Patent Application No. 16 / 014,863, filed June 21, 2018, and U.S. Patent Application No. 16 / 015,145, filed June 21, 2018, which claim priority to U.S. Patent Application No. 62 / 522386, filed June 21, 2017, U.S. Patent Application No. 62 / 522846, filed June 21, 2017, U.S. Patent Application No. 62 / 522851, filed June 21, 2017, and U.S. Patent Application No. 62 / 522860, filed June 21, 2017, all of which are incorporated by reference in their entirety herein. For comparison, a baseline system with R-404A running at the high stage and a single high capacity vapor compressor running at the low stage is also tested.

[0226] Operating conditions: Baseline R404A Combined MT / LT (non-micro) system ● Refrigeration capacity ○ Low temperature: 33,000W ○ Medium temperature: 67,000W ● Volumetric efficiency: 95% for both MT and LT ● Compressor isentropic efficiency ○ Medium temperature = 70% and low temperature = 67% ● Condensing temperature=105°F ● Medium temperature evaporation temperature: 20°F ● Low temperature evaporation temperature: -20°F ● Evaporator superheat: 10°F (both medium and low temperature) ● Intake line temperature rise (due to heat transfer to the surroundings) Baseline: Medium temperature: 25°F, Low temperature: 50°F ○ Built-in without Cascade / SLHX: Medium: 10°F, Low: 25°F ○ Built-in with Cascade / SLHX: Medium temperature: 10°F, Low temperature: 15°F ● SLHX efficiency when in use: 65% Performance results are reported below in Tables E9A-E9E.

[0227] [Table 28]

[0228] [Table 29]

[0229] [Table 30]

[0230] [Table 31]

[0231] [Table 32]

[0232] From Tables E9A to E9E above, it can be seen that the micro-cascade system has a COP that is at least about 120% higher than the baseline medium temperature DX system using R404A.

[0233] Example 10: Non-flammable secondary refrigerant with pressure above atmospheric pressure The refrigerants of the present invention, including refrigerants E1-E7, are useful as secondary fluids in secondary fluid refrigeration systems. The refrigerants of the present invention, including each of refrigerants E1-E7, have the necessary properties to ensure that the operating pressure of the refrigerant does not fall below atmospheric pressure at a given evaporator temperature, so that air does not enter the system, while at the same time being low enough to prevent significant leakage. • Table 10 gives the refrigerant pressures for evaporating temperatures ranging from -5°C to 10°C, covering a range of operating conditions for air conditioning applications. - It can be observed from Table 10 that all refrigerants maintain a pressure above atmospheric pressure. The primary refrigerant used in the vapor compression loop may be selected from the group consisting of R404A, R507, R410A, R455A, R32, R466A, R44B, R290, R717, R452B, R448A, R1234ze(E), R1234yf, and R449A. The temperature of the air (or object) to be cooled may be between about 25°C and about 0°C.

[0234] [Table 33]

[0235] Example 11: Performance in a fixed air conditioning system Performance tests were conducted on refrigerants E1-E7 in a stationary air conditioning system under various condenser temperature conditions. This analysis was carried out to evaluate the efficiency (COP) of refrigerants E1-E7 in this system under the following operating conditions: ● Condensation temperature = 45℃~65℃ Condenser subcooling = 5.0℃ Evaporation temperature = 10℃, corresponding indoor ambient temperature = 35℃ Evaporator superheat = 5.0℃ ● Compressor isentropic efficiency = 72% ● Volumetric efficiency = 100%

[0236] [Table 34] Refrigerants E1-E7 exhibit similar efficiency to R134a over a range of condensation temperatures corresponding to different ambient temperatures, and compositions E1-E5 exhibit superior performance when all relevant performance factors are taken into account, for example as described in relation to Example 1.

[0237] Example 12: Performance in a commercial air conditioning system Performance tests were conducted on refrigerants E1 to E7 in a commercial air conditioning system under various condenser temperature conditions. This analysis was conducted to evaluate the efficiency (COP) of refrigerants E1 to E7 in this system under the following conditions: Operating conditions: ● Condensation temperature = 45℃~65℃ Condenser subcooling = 5.0℃ Evaporation temperature = 10℃ Evaporator superheat = 5.0℃ ● Compressor isentropic efficiency = 72% ● Volumetric efficiency = 100%

[0238] [Table 35]

[0239] Refrigerants E1-E6 exhibit similar efficiency to R134a over a range of condensation temperatures corresponding to different ambient temperatures, with compositions E1, E2, E3 and E4 exhibiting superior performance when all relevant performance factors are taken into account, for example as described in relation to Example 1.

[0240] Example 13: Performance in an extreme temperature air conditioning system Performance tests were conducted on refrigerants E1-E7 in a stationary air conditioning system under various condenser temperature conditions. This analysis was carried out to evaluate the efficiency (COP) of refrigerants E1-E7 in this system under the following operating conditions: ● Condensation temperature = 55℃~95℃ Condenser subcooling = 5.0℃ Evaporation temperature = 10℃, corresponding indoor ambient temperature = 35℃ Evaporator superheat = 5.0℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100%

[0241] [Table 36]

[0242] Refrigerants E1-E7 exhibit similar efficiency to R134a over a range of condensation temperatures corresponding to different ambient temperatures, and compositions E1-E5 exhibit superior performance when all relevant performance factors are taken into account, for example as described in relation to Example 1.

[0243] Comparative Example C2 - Performance in Extreme Temperature Air Conditioning System Example E13 is repeated at a condenser temperature of 75° C., except that refrigerants C4 and C5 are tested for comparison in terms of GWP, capacity, COP, and slope. As reported in Table C2, C4 and C5 each have a GWP of over 150, but the C4 and C5 refrigerants were chosen for comparison because they had the lowest GWP of the refrigerants in Table C. Table C2 below also shows the results in each case for refrigerants E2B and E4 for comparison, as representative of the performance of the refrigerants of the present invention.

[0244] [Table 37]

[0245] As can be seen from Table C2, the C4 and C5 refrigerants (consisting of HFO-1234ze(E), 1224yd(Z), and HFC-134) are unable to achieve a GWP below 150, or an evaporator slope below 3° C., or a capacity above 70%, or an efficiency comparable to that of R134a as achieved by asE2B or E4. This illustrates a highly unexpected and advantageous result of the refrigerants of the present invention.

[0246] Example 14: Performance in a high temperature heat pump system Performance tests were conducted on refrigerants E1-E7 in a stationary air conditioning system under various condenser temperature conditions. This analysis was carried out to evaluate the efficiency (COP) of refrigerants E1-E7 in this system under the following operating conditions: ● Condensation temperature = 55℃~95℃ Condenser subcooling = 5.0℃ Evaporation temperature = 30℃ Evaporator superheat = 5.0℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100%

[0247] [Table 38]

[0248] Refrigerants E1-E7 exhibit similar efficiency to R134a over a range of condensation temperatures corresponding to different ambient temperatures, and compositions E1-E5 exhibit superior performance when all relevant performance factors are taken into account, for example as described in connection with Example E1.

[0249] Comparative Example C3 - Performance in a High Temperature Heat Pump System Example E14 is repeated at a condenser temperature of 75° C., except that refrigerants C4 and C5 are tested for comparison in terms of GWP, capacity, COP, and slope. As reported in Table C3, C4 and C5 each have a GWP of over 150, but the C4 and C5 refrigerants were chosen for comparison because they had the lowest GWP of the refrigerants in Table C. Table C3 below also shows the results in each case for refrigerants E2B and E4 for comparison, as representative of the performance of the refrigerants of the present invention.

[0250] [Table 39]

[0251] As can be seen from Table C3, the C4 and C5 refrigerants (consisting of HFO-1234ze(E), 1224yd(Z), and HFC-134) are unable to achieve a GWP below 150, or an evaporator gradient below 3° C., or a capacity above 70%, or an efficiency comparable to that of R134a as achieved by E2B or E4. This illustrates a highly unexpected and advantageous result of the refrigerants of the present invention.

[0252] Example 15: Performance in a Transportation (Refrigerated Trucks, Containers) Medium Temperature Refrigeration Application with and without a Suction Line (SL) / Liquid Line (LL) Heat Exchanger (HX) Performance tests were conducted on refrigerants E1-E7 in a transport refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX) under medium temperature refrigeration conditions. The analysis was conducted to evaluate the efficiency (COP) of refrigerants E1-E7 in this system at different effectiveness levels of SL-LL HX under the following conditions: The operating conditions were as follows: Condensation temperature = 45℃ ● Condensation temperature - ambient temperature = 10℃ Condenser subcooling = 0.0°C (system with a receiver) Evaporation temperature = -8℃ ● Evaporator superheat = 5.5℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 15℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75%

[0253] [Table 40]

[0254] Table 15 shows the performance of refrigerants E1-E7 in a transport refrigeration system. The results in the column with SL-LL HX efficiency of "0%" represent systems without SL-LL HX, and it will be understood that refrigerants E1-E7 show improved performance in terms of efficiency (COP) over R134a when employing a SL / LL heat exchanger, and compositions E1-E5 show superior performance when all relevant performance factors are considered, for example as described in relation to Example E1.

[0255] Example 16: Performance in Transportation (Refrigerated Trucks, Containers) Low Temperature Refrigeration Applications with and without Intake Line / Liquid Line Heat Exchanger Performance tests were conducted for refrigerants E1-E6 in a transport refrigeration system with and without a suction line / liquid line heat exchanger (SL / LL HX) at low temperature refrigeration conditions. The analysis was carried out to evaluate the efficiency (COP) of refrigerants E1-E7 in this system at different effectiveness levels of SL-LL HX under the following conditions: The operating conditions were as follows: Condensation temperature = 45℃ ● Condensation temperature - ambient temperature = 10℃ Condenser subcooling = 0.0°C (system with a receiver) Evaporation temperature = -35℃, corresponding internal temperature = -25℃ ● Evaporator superheat = 5.5℃ ● Compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise in intake line = 15℃ ● Heat exchange rate of intake line / liquid line heat exchanger: 0%, 35%, 55%, 75%

[0256] [Table 41]

[0257] It will be appreciated that the results in the column with a SL-LL HX efficiency of "0%" represent systems that do not use SL-LL HX and that refrigerants E1-E7 exhibit improved performance in terms of efficiency (COP) over R134a when employing a SL / LL heat exchanger, with compositions E1-E5 exhibiting superior performance when all relevant performance factors are considered, for example as described in relation to Example E1.

[0258] Example 17: Electronic Cooling Performance testing of refrigerants E1-E7 is performed to evaluate cooling of electronic devices, including cooling of chips, electronic boards, batteries (including batteries used in cars, trucks, buses, and other electronic transportation vehicles), computers, etc., including forms of heat pipes, thermosyphons, etc., as well as vapor compression cooling. Analyses are performed to evaluate the performance of refrigerants E1-E6 in these applications. Refrigerants E1-E7 perform similarly to R134a, with compositions E1-E5 exhibiting exceptional performance when all relevant performance factors are considered, for example as described in connection with Example E1.

[0259] Example 18: Performance of the refrigerant pairs of the present invention in a cascade refrigeration system Cascade systems are typically used in applications where there is a large temperature difference between the ambient temperature and the inside temperature (e.g., about 50-80°C, such as about 60-70°C) (e.g., the temperature difference between the air side of the condenser in the high stage and the air side of the evaporator in the low stage). For example, a cascade system may be used to freeze products in a supermarket. In this example, a high stage / low stage pair of refrigerants 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 as follows: Condensation temperature = 45℃ ● High stage condensation temperature - ambient temperature = 10℃ - Subcooling of high stage condenser = 0.0℃ (system with receiver) Evaporation temperature = -30℃, corresponding internal temperature = -18℃ ● Low-stage evaporator superheat = 3.3℃ High and low stage compressor isentropic efficiency = 65% ● Volumetric efficiency = 100% ● Temperature rise at low stage of intake line = 15℃ ● Temperature rise at high stage of intake line = 10℃ ● Intermediate heat exchanger with indicated low stage refrigerant condensation temperatures = 0C, 5℃ and 10℃ ● Intermediate heat exchanger superheat = 3.3℃ ● Temperature difference at intermediate heat exchanger = 8℃ Performance results are reported in Table E18.

[0260] [Table 42]

[0261] Example 19: Microcascade refrigeration system The micro-cascade system combines a conventional mid-temperature DX refrigeration system with or without a suction line liquid line heat exchanger (SLHX). In this example, the advantageous combination of the refrigerant pairs of the present invention in the high and low stages is tested, as shown in Table 19 below. The low stage is used, which contains several small low temperature self-contained refrigeration systems. For comparison, a baseline system running with R-404A operating in the high and low stages is also tested. Operating conditions: Baseline R404A Combined MT / LT (non-micro) system ● Refrigeration capacity ○ Low temperature: 33,000W ○ Medium temperature: 67,000W ● Volumetric efficiency: 95% for both MT and LT ● Compressor isentropic efficiency ○ Medium temperature = 70% and low temperature = 67% ● Condensing temperature: 105°F ● Medium temperature evaporation temperature: 20°F ● Low temperature evaporation temperature: -20°F, evaporator superheat: 10°F (both medium and low temperature) ● Intake line temperature rise (due to heat transfer to the surroundings) Baseline: Medium temperature: 25°F, Low temperature: 50°F ○ Built-in without Cascade / SLHX: Medium: 10°F, Low: 25°F ○ Built-in with Cascade / SLHX: Medium temperature: 10°F, Low temperature: 15°F ● SLHX efficiency when in use: 65% Performance results are reported in Table E19.

[0262] [Table 43]

[0263] Table E19 above shows that a micro-cascade system using the inventive refrigerant pairs according to the present invention has a COP that is at least about 120% higher than the baseline medium temperature DX system with R404A.

Claims

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

2. a. about 76% to about 84% by weight of HFO-1234ze(E); b. 11 wt.% or less of HFC-134a; c. 14 wt.% or less of HFO-1224yd(Z).

3. a. 83.5 wt% + 0.5 wt% / - 2 wt% HFO-1234ze(E); b. 10 wt% + 2 wt% / - 0.5 wt% HFC-134a; c. 6.5 wt% +2 wt% / -0.5 wt% HFO-1224yd(Z).

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

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

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

7. 10. The cascade refrigeration system of claim 9, wherein the low-stage refrigerant is a Class A1 or Class A2L refrigerant.

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

9. 13. The cascade refrigeration system of claim 12, wherein the low-stage refrigerant comprises one or more of CO2, propane, HFO-1234yf, R454C, and R455A and condenses in the intercircuit heat exchanger within a temperature range of about -5°C to about -15°C.

10. 10. A commercial refrigeration system comprising the cascade refrigeration system of claim 9.

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