Refrigerant Compositions for Refrigerant Compressor Systems

Abstract

A vapor compression refrigeration system including a reciprocating, scroll, or rotary compressor and a refrigerant composition, the refrigerant composition including difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane (R-290).

Description

[Technical Field]

[0001] The present invention is directed to refrigerant compositions for refrigerant compressors in vapor compression systems. [Background technology]

[0002] Refrigerants with very low global warming potential (GWP < 150) are needed to meet regulatory requirements for various applications and market segments. Several alternatives have been developed to replace traditional high-GWP refrigerants, such as R-404A. Many of the low-GWP refrigerants proposed for this replacement, such as R-457A, exhibit higher discharge temperatures than the high-GWP refrigerants they replace, such as R-404A. This can limit their effectiveness by reducing the operating range of compressors in vapor compression systems. This can be particularly important for hermetic compressors used in low- or medium-temperature refrigeration, as many of these models do not employ active discharge temperature control systems such as liquid or vapor injection. If left unchecked, the higher discharge temperatures produced in these applications could reduce compressor life. Without the ability to actively mitigate discharge temperatures, the use of these compressors may be limited to applications with higher evaporator temperatures and / or lower condensing temperatures. Summary of the Invention [Means for solving the problem]

[0003] In an exemplary embodiment, a composition includes a refrigerant composition comprising difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane (R-290).

[0004] In another exemplary embodiment, a refrigeration system includes a hermetic compressor and a refrigerant composition, the refrigerant composition including difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane (R-290).

[0005] In another exemplary embodiment, a method of replacing a first refrigerant composition comprising R-404A, R-457A, R-290, R-454C, or 507A with a second refrigerant composition comprising 76-84 wt.% 2,3,3,3-tetrafluoropropene, 16-19 wt.% difluoromethane, and 1.0-5.0 wt.% propane in a refrigeration system equipped with a hermetic compressor.

[0006] In another exemplary embodiment, a method of operating a hermetic compressor as part of a refrigeration system includes receiving a refrigerant composition comprising difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane (R-290) through the hermetic compressor, and compressing the refrigerant composition with the hermetic compressor. The compressor discharge temperature is between 78.0°C and 102.0°C.

[0007] Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, which illustrates, by way of example, the principles of the invention. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of a refrigeration system according to one embodiment. [Figure 2] 1 is a schematic diagram of a refrigeration system according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] definition A refrigerant is defined as a heat transfer fluid that undergoes a phase change from liquid to gas and back again in a cycle used to transfer heat.

[0010] A refrigeration system is a system (or equipment) used to create a heating or cooling effect in a specific space. Heat transfer systems or refrigeration systems can be mobile or stationary systems.

[0011] Examples of refrigeration systems include any type of cooling and air conditioning system, including, but not limited to, stationary heat transfer systems, air conditioners, freezers, refrigerators, heat pumps, water chillers, flooded evaporative chillers, direct expansion chillers, walk-in coolers, mobile or transport refrigeration systems, mobile refrigeration systems, mobile air conditioning units, dehumidifiers, and combinations thereof.

[0012] Refrigeration capacity (also called cooling capacity) is a term that defines the change in enthalpy of the refrigerant in the evaporator per pound of circulating refrigerant, or the heat removed by the refrigerant in the evaporator per unit volume (volume) of refrigerant vapor leaving the evaporator. Refrigeration capacity is a measure of the ability of a refrigerant or heat transfer composition to produce cooling. Thus, the higher this capacity, the greater the degree of cooling produced. Cooling rate refers to the heat removed per unit time by the refrigerant in the evaporator.

[0013] The Coefficient of Performance (COP) is the heat removed divided by the energy input required to run the cycle. The higher the COP, the more energy efficient it is. COP is directly related to the Energy Efficiency Ratio (EER), which is a rating of the efficiency of a refrigeration or air conditioning unit at a specific combination of internal and external temperatures.

[0014] Temperature gradient (sometimes simply referred to as "gradient") is the absolute value of the difference between the start and end temperatures of a phase change process by a refrigerant within a refrigerant system component, excluding any subcooling or superheating. The term can be used to describe the condensation or evaporation of near-azeotropic or non-azeotropic compositions. When referring to the temperature gradient of a refrigeration system, air conditioning system, or heat pump system, it is common to provide the average temperature gradient, which is the average of the temperature gradient in the evaporator and the temperature gradient in the condenser.

[0015] Net refrigeration effect is the amount of heat absorbed by each kg of refrigerant in the evaporator to produce useful cooling.

[0016] Mass flow is the amount of refrigerant (in kilograms) circulating through a refrigeration system, heat pump system, or air conditioning system at a given time.

[0017] As used herein, the term "lubricant" means any material added to a composition or compressor (and in contact with any heat transfer composition in use in any heat transfer system) that provides lubrication to the compressor to help prevent parts from seizing.

[0018] As used herein, a compatibilizer is a compound that improves the solubility of the hydrofluorocarbon of the disclosed compositions in a heat transfer system lubricant. In some embodiments, the compatibilizer improves oil return to the compressor. In some embodiments, the compositions are used with a system lubricant to reduce the viscosity of the oil-rich phase.

[0019] As used herein, oil return refers to the ability of a heat transfer composition to carry lubricant through a heat transfer system and return the lubricant to the compressor. That is, during use, it is not uncommon for a portion of the compressor lubricant to be carried away by the heat transfer composition from the compressor to other parts of the system. In such systems, if the lubricant is not efficiently returned to the compressor, the compressor will eventually fail due to lack of lubrication.

[0020] As used herein, a "ultraviolet" dye is defined as a UV fluorescent or phosphorescent composition that absorbs light in the ultraviolet or "near" ultraviolet region of the electromagnetic spectrum. The fluorescence produced by a UV fluorescent dye can be detected under UV irradiation, emitting at least some radiation having a wavelength in the range of 10 nanometers to about 775 nanometers.

[0021] Flammability is a term used to refer to the ability of a composition to ignite and / or propagate a flame. For refrigerants and other heat transfer compositions, the lower flammability limit (LFL) is the lowest concentration of the heat transfer composition in air that can propagate a flame through a homogeneous mixture of the composition and air under the test conditions described in ASTM E681. The upper flammability limit (UFL) is the highest concentration of the heat transfer composition in air that can propagate a flame through a homogeneous mixture of the composition and air under the same test conditions. Testing under ASTM E681 conditions also determines whether a refrigerant compound or mixture is flammable or nonflammable.

[0022] When a refrigerant leaks, the lower-boiling components of the mixture may leak preferentially. This can change the composition of the system and the vapor leak over time. This can cause a non-flammable mixture to become flammable under potential leak conditions. To be classified as non-flammable by ASHRAE (American Society of Heating, Refrigeration and Air-Conditioning Engineers), a refrigerant or heat transfer composition must be non-flammable not only when blended but also under leak conditions. ASHRAE defines different flammability classifications. Class 1 refrigerants do not propagate flames. Class 3 refrigerants are more flammable, and Class 2 refrigerants are referred to as flammable. Class 2L refrigerants are less flammable and have a burning velocity of ≤10 cm / sec.

[0023] Global warming potential (GWP) is an index used to estimate the relative global warming contribution resulting from the atmospheric emission of one kilogram of a particular greenhouse gas compared to the emission of one kilogram of carbon dioxide. GWP can be calculated for various time horizons and indicates the impact of a given gas's atmospheric lifetime. The GWP over a 100-year time horizon is the value usually referred to. For mixtures, a weighted average can be calculated based on the individual GWPs of each component.

[0024] Ozone depletion potential (ODP) is a number that indicates the degree of ozone destruction caused by a substance. ODP is the ratio of a chemical's effect on the ozone compared to the effect of a similar mass of CFC-11 (fluorotrichloromethane). For this reason, CFC-11 is defined as having an ODP of 1.0. Other CFCs and HCFCs have ODPs ranging from 0.01 to 1.0. HFCs contain no chlorine or other ozone-depleting halogens and therefore have an ODP of zero.

[0025] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, are intended to cover non-exclusive inclusions. For example, a composition, process, method, article, or device that comprises listed elements is not necessarily limited to only those elements, but may include other elements not expressly listed or associated with such composition, process, method, article, device, etc.

[0026] The transitional phrase "consisting of" excludes any unspecified element, step, or ingredient. When used in a claim, such phrase excludes from the claim the inclusion of materials other than those recited, except for impurities normally accompanying the materials. When the phrase "consisting of" appears within a clause in the body of a claim rather than immediately following the preamble, the phrase limits only the elements set forth in that clause and does not exclude other elements from the claim as a whole.

[0027] The transitional phrase "consisting essentially of" is used to define a composition, method, or apparatus that includes materials, steps, features, components, or elements in addition to those literally disclosed, provided that these additionally included materials, steps, features, components, or elements do not materially affect the basic and novel characteristics of the claimed invention. The term "consisting essentially of" has a meaning intermediate between "comprising" and "consisting of." Typically, the components of a refrigerant mixture, and the refrigerant mixture itself, may contain small amounts (e.g., less than about 0.5% by weight in total) of impurities and / or by-products (e.g., from the production of the refrigerant components or recycling of refrigerant components from other systems) that do not materially affect the novel and basic characteristics of the refrigerant mixture.

[0028] It is to be understood that when applicant defines an invention or portions thereof with open-ended terms such as "comprising," the description should be construed as also describing inventions using the terms "consisting essentially of" or "consisting of" (unless otherwise expressly stated).

[0029] Additionally, the use of "a" or "an" is used to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be interpreted to include one or at least one, and the singular also includes the plural unless it is clear that a different meaning is intended.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the disclosed compositions, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety, unless a specific passage is cited. In the event of a conflict, the present specification, including definitions, will control. Furthermore, the materials, methods, and examples are merely illustrative and are not intended to be limiting.

[0031] 2,3,3,3-Tetrafluoropropene may also be referred to as HFO-1234yf, HFC-1234yf, or R1234yf. HFO-1234yf can be made by methods known in the art, such as by dehydrofluorination of 1,1,1,2,3-pentafluoropropane (HFC-245eb) or 1,1,1,2,2-pentafluoropropane (HFC-245cb).

[0032] Difluoromethane (HFC-32 or R-32) is commercially available or can be made by methods known in the art, such as, for example, the dechlorination of methylene chloride.

[0033] Propane (R-290) is commercially available from a number of gas suppliers or can be produced by any of a number of well-known methods.

[0034] Compositions and Systems A low global warming potential (GWP) refrigerant composition is provided that exhibits low discharge temperatures and high heat capacity, and is suitable for use in hermetic compressors used in refrigeration applications.

[0035] In another embodiment, a refrigeration system is provided that includes a hermetic compressor.

[0036] An embodiment of a refrigeration system 100 is shown in Figure 1. In the embodiment of Figure 1, refrigeration system 100 includes a receiving tank 110. Receiving tank 110 contains a refrigerant composition and supplies the refrigerant composition to the other components of refrigeration system 100 during operation.

[0037] The refrigerant composition may be selected from materials with a low global warming potential (GWP). In some embodiments, the refrigerant composition exhibits a GWP of less than 180, less than 150, and / or less than 130. In some embodiments, the refrigerant composition may be selected to replace a refrigerant composition having a high GWP. In some embodiments, the refrigerant composition may be selected to replace refrigerant compositions such as R-404A, R-290, R-454C, R-457A, and R-507A. The replacement composition desirably provides similar or improved properties compared to R-404A. Similar properties may include flammability, discharge temperature, and heat transport capacity.

[0038] Refrigerant compositions suitable for replacing R-404A refrigerant may include difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane (R-290). In some embodiments, the refrigerant composition may be a non-azeotropic refrigerant composition.

[0039] In one embodiment, refrigeration system 100 may be a direct expansion refrigeration system. During operation of refrigeration system 100, a refrigerant composition circulates throughout refrigeration system 100 as part of a heat transfer process. In the example of FIG. 1 , receiving tank 110 is operably coupled to evaporator 120 via an expansion device 125, such as an orifice tube, a capillary tube, a thermal expansion valve, or an electronic expansion valve. Expansion device 125 supplies the refrigerant composition to evaporator 120. In some embodiments, receiving tank 110 is optional. In such embodiments, the refrigerant is supplied directly to evaporator 120 without a receiver. In one embodiment, the refrigerant composition is conveyed between receiving tank 110 and evaporator 120 via expansion device 125. In some embodiments, evaporator 120 may operate in a low-temperature mode. For purposes described herein, low-temperature evaporator operation is between −40° C. and −18° C. In some embodiments, evaporator 120 may operate in a medium-temperature mode. For purposes herein, operation of a medium temperature evaporator is between -20°C and -5°C.

[0040] The evaporator 120 is operably connected to the compressor 140 via a suction line 135. The compressor 140 increases the pressure of the vapor refrigerant entering the compressor 140. In some embodiments, the compressor 140 may be a hermetic compressor. In some embodiments, the hermetic compressor is a rotary compressor, a scroll compressor, or a reciprocating compressor. In some embodiments, the hermetic compressor is a low back pressure (LBP) hermetic compressor. In another embodiment, the hermetic compressor is a low back pressure (LBP) hermetic reciprocating compressor.

[0041] In one embodiment, the refrigerant composition is a non-azeotropic composition comprising difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane (R-290). In some embodiments, the discharge temperature of the hermetic compressor is 78.0°C to 102.0°C, 80.0°C to 100.0°C, 82°C to 99.0°C, 80.0°C to 100.0°C, 82°C to 99.0°C, 80.0°C to 90.0°C, 80.0°C to 100.0°C, 90°C to 99.0°C, and combinations thereof.

[0042] The compressor 140 is operatively connected to a condenser 160. The condenser 160 receives pressurized vapor refrigerant and enables the pressurized vapor evaporator to transfer heat to an external medium and condense to a liquid state.

[0043] The condenser 160 is operatively connected to the receiving tank 110. The liquid refrigerant returns to the receiving tank 110 and is supplied to the evaporator 120 again for heat absorption.

[0044] In compositions intended to replace traditional high GWP refrigerants, it is desirable for the replacement refrigerant composition to exhibit a lower GWP and similar or improved refrigerant properties compared to the refrigerant being replaced. In some embodiments, the refrigerant compositions are intended to replace R-457A (a mixture containing 18 wt.% HFC-32, 70 wt.% HFO-1234yf, and 12 wt.% HFC-152a (1,1-difluoroethane)), R-454C (a mixture containing 21.5 wt.% HFC-32 and 78.5 wt.% HFO-1234yf), R-404A (a mixture of 44 wt.% HFC-125 (pentafluoroethane), 52 wt.% HFC-143a (1,1,1-trifluoroethane), and 4 wt.% HFC-134a (1,1,1,2-tetrafluoroethane)), R-507A (a mixture containing 50 wt.% HFC-125 and 50 wt.% HFC-143a), or R-290 (propane).

[0045] In some embodiments, the refrigerant composition comprises R-32 in an amount of 15-20 wt.% based on the weight of the refrigerant composition, R-1234yf in an amount of 74-84 wt.% based on the weight of the refrigerant composition, and propane in an amount of 1-10 wt.% based on the weight of the refrigerant composition. In some embodiments, the refrigerant composition comprises R-32 in an amount of 16-19 wt.% based on the weight of the refrigerant composition, R-1234yf in an amount of 76-84 wt.% based on the weight of the refrigerant composition, and propane in an amount of 1.0-5.0 wt.% based on the weight of the refrigerant composition. In one embodiment, the refrigerant composition comprises R-32 in an amount of 16-18 wt.% based on the weight of the refrigerant composition, R-1234yf in an amount of 79-83 wt.% based on the weight of the refrigerant composition, and propane in an amount of 1.0-3.0 wt.% based on the weight of the refrigerant composition. In another embodiment, the refrigerant composition comprises R-32 in an amount of 17-18 wt%, based on the weight of the refrigerant composition, R-1234yf in an amount of 80-82 wt%, based on the weight of the refrigerant composition, and propane in an amount of 2.0-3.0 wt%, based on the weight of the refrigerant composition. In one embodiment, the refrigerant composition comprises R-32 in an amount of 18 wt%, based on the weight of the refrigerant composition, R-1234yf in an amount of 80 wt%, based on the weight of the refrigerant composition, and propane in an amount of 2.0 wt%, based on the weight of the refrigerant composition. In another embodiment, the refrigerant composition comprises R-32 in an amount of 17 wt%, based on the weight of the refrigerant composition, R-1234yf in an amount of 81 wt%, based on the weight of the refrigerant composition, and propane in an amount of 2.0 wt%, based on the weight of the refrigerant composition. In one embodiment, the refrigerant composition comprises R-32 in an amount of 18 wt.% based on the weight of the refrigerant composition, R-1234yf in an amount of 81 wt.% based on the weight of the refrigerant composition, and propane in an amount of 1.0 wt.% based on the weight of the refrigerant composition. In another embodiment, the refrigerant composition comprises R-32 in an amount of 17 wt.% based on the weight of the refrigerant composition, R-1234yf in an amount of 82 wt.% based on the weight of the refrigerant composition, and propane in an amount of 1.0 wt.% based on the weight of the refrigerant composition.

[0046] In one embodiment, the propane is present in an amount of 0.5 to 1.0 wt % based on the weight of the refrigerant composition.

[0047] In particular, any of the compositions in Table A can be used in a refrigeration system equipped with a hermetic compressor.

[0048] [Table 1]

[0049] The refrigerant composition may further comprise one or more optional non-refrigerant components selected from the group consisting of lubricants, dyes (including UV dyes), solubilizers, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure additives, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam control agents, viscosity index improvers, pour point depressants, detergents, viscosity modifiers, and mixtures thereof. In some embodiments, the optional non-refrigerant composition may also be referred to as an additive. Indeed, many of these optional non-refrigerant components fit one or more of these categories and may themselves possess qualities that help achieve one or more performance characteristics.

[0050] A lubricant can be included in the refrigerant composition to facilitate operation and extend the useful life of the compressor 140. The solubility and miscibility of the lubricant with the refrigerant composition can improve the performance of the lubricant and extend the useful life of the compressor 140. In some embodiments, the lubricant can include mineral oil, alkyl benzene, polyol ester, polyalkylene glycol, polyvinyl ether, polycarbonate, perfluoropolyether, silicone, silicate ester, phosphate ester, paraffin, naphthene, polyalphaolefin, and combinations thereof. In certain embodiments, the lubricant includes a polyol ester or polyvinyl ether. In one embodiment, the lubricant includes a polyol ester. In another embodiment, the lubricant includes a polyvinyl ether.

[0051] The optional non-refrigerant component used with the refrigerant composition may be a stabilizer selected from the group consisting of hindered phenols, thiophosphates, butylated triphenyl phosphorothioates, organophosphates or phosphites, aryl alkyl ethers, terpenes, terpenoids, epoxides, fluorinated epoxides, oxetanes, ascorbic acid, thiols, lactones, thioethers, amines, nitromethane, alkyl silanes, benzophenone derivatives, aryl sulfides, divinyl terephthalic acid, diphenyl terephthalic acid, ionic liquids, and mixtures thereof, including mixtures of any of the stabilizers disclosed in this paragraph.

[0052] The stabilizer may be selected from the group consisting of butylated hydroxytoluene (BHT); tocopherol; hydroquinone; t-butylhydroquinone; monothiophosphates; and dithiophosphates (commercially available from Ciba Specialty Chemicals, Basel, Switzerland (hereinafter "Ciba") under the trade name Irgalube® 63); dialkylthiophosphates (commercially available from Ciba under the trade names Irgalube® 353 and Irgalube® 350, respectively); butylated triphenylphosphorothionate (commercially available from Ciba under the trade name Irgalube® 232); amine phosphates (commercially available from Ciba under the trade name Irgalube® 353); hindered phosphite (commercially available from Ciba under the trade name Irgafos® 349); hindered phosphite (commercially available from Ciba under the trade name Irgafos® 168), and tris-(di-tert-butylphenyl) phosphite (commercially available from Ciba under the trade name Irgafos® OPH); (Di-n-octyl phosphite); and isodecyl diphenyl phosphite (commercially available from Ciba under the trade name Irgafos® DDPP); trimethyl phosphate, triethyl phosphate, tributyl phosphite trialkyl phosphates such as trioctyl phosphate, trioctyl phosphate, and tri(2-ethylhexyl) phosphate; triaryl phosphates including triphenyl phosphate, tricresyl phosphate, and trixylenyl phosphate, and mixed alkylaryl phosphates including isopropylphenyl phosphate (IPPP) and bis(t-butylphenyl)phenyl phosphate (TBPP); butylated triphenyl phosphates (e.g., those commercially available under the trademark Syn-O-Ad®, including Syn-O-Ad® 8784); tert-butylated triphenyl phosphates (such as those commercially available under the trademark Durad® 620); isopropylated triphenyl phosphates (e.g., those commercially available under the trademark Durad® 220 and Durad® 110); anisole; 1,4-dimethoxybenzene; 1,4-diethoxybenzene; 1,3,5-trimethoxybenzene;Myrcene, alloocimene, limonene (especially d-limonene); retinal; pinene (alpha or beta form); menthol; geraniol; farnesol; farnesene (alpha or beta form); phytol; vitamin A; terpinene; delta-3-carene; terpinolene; phellandrene; fenthen; dipentene; caratenoids such as lycopene, beta-carotene, and xanthophylls such as zeaxanthin; retinoids such as hepaxanthin and isotretinoin; bornane; 1,2-propylene oxide; 1,2-Butylene oxide; n-butyl glycidyl ether; trifluoromethyl oxirane; 1,1-bis(trifluoromethyl)oxirane; 3-ethyl-3-hydroxymethyl-oxetane, e.g., OXT-101 (Toagosei); 3-ethyl-3-((phenoxy)methyl)-oxetane, e.g., OXT-211 (Toagosei); 3-ethyl-3-((2-ethylhexyloxy)methyl)-oxetane, e.g., OXT-212 (Toagosei); ascorbic acid; methanethiol (methyl mercaptan); ethylene Tanthiol (ethyl mercaptan); coenzyme A; dimercaptosuccinic acid (DMSA); grapefruit mercaptan ((R)-2-(4-methylcyclohex-3-enyl)propane-2-thiol); cysteine ​​((R)-2-amino-3-sulfanyl-propanoic acid); lipoamide (1,2-dithiolane-3-pentanamide); 5,7-bis(1,1-dimethylethyl)-3-[2,3 (or 3,4-)-dimethylphenyl]-2(3H)-benzofuranone (available from Ciba under the trade name Irganox) benzyl phenyl sulfide; diphenyl sulfide; diisopropylamine; dioctadecyl 3,3'-thiodipropionate (commercially available from Ciba under the trade name Irganox® PS802 (Ciba)); didodecyl 3,3'-thiopropionate (commercially available from Ciba under the trade name Irganox® PS800); di-(2,2,6,6-tetramethyl-4-piperidyl) sebacate (commercially available from Ciba under the trade name Tinuvin® 770);Poly-(N-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxy-piperidyl succinate (commercially available from Ciba under the trade name Tinuvin® 622LD); methyl bistarrowamine; bistarrowamine; phenol-α-naphthylamine; bis(dimethylamino)methylsilane (DMAMS); tris(trimethylsilyl)silane (TTMSS); vinyltriethoxysilane; vinyltrimethoxysilane; 2,5-difluorobenzophenone; 2',5'-dihydroxyacetophenone; 2-aminobenzophenone; 2-chlorobenzophenone; benzyl phenyl sulfide; diphenyl sulfide; dibenzyl sulfide; ionic liquids; and mixtures and combinations thereof.

[0053] In particular, the optional non-refrigerant component may be a polymerization inhibitor, which may include terpenes or terpenoids, butylated triphenylphosphorothionates, benzophenone and its derivatives, terephthalates, phenols, epoxides, and combinations of any of these classes. Polymerization inhibitors may include, but are not limited to, myrcene, alloocimene, limonene (especially d-limonene); retinal; pinene (alpha or beta form); menthol; geraniol; farnesol; farnesene (alpha or beta form); phytol; vitamin A; terpinene (alpha or gamma form); delta-3-carene; terpinolene; phellandrene; fenthen; dipentene; caratenoids such as lycopene, beta-carotene, and xanthophylls such as zeaxanthin; retinoids such as hepaxanthin and isotretinoin; bornane, butylated triphenylphosphorothionate (commercially available from Ciba under the trade name Irgalube® 232), divinyl terephthalate, diphenyl terephthalate, butylhydroxytoluene (BHT), tocopherol, hydroquinone, 1,2-propylene oxide glycidyl ether, 1,2-butylene oxide, butylphenyl glycidyl ether, pentylphenyl glycidyl ether, hexylphenyl glycidyl ether, heptylphenyl glycidyl ether, octylphenyl glycidyl ether, nonylphenyl glycidyl ether, decylphenyl glycidyl ether, glycidyl methylphenyl ether, 1,4-glycidylphenyl diether, 4-methoxyphenyl glycidyl ether, naphthyl glycidyl ether, 1,4-diglycidyl naphthyl diether, butylphenyl glycidyl ether, n-butyl glycidyl ether, isobutyl glycidyl ether, hexanediol diglycidyl ether, allyl glycidyl ether, polypropylene glycol diglycidyl ether, trifluoromethyloxirane, 1,1-bis(trifluoromethyl)oxirane, and combinations thereof.

[0054] Any non-refrigerant compound used with the compositions of the present invention may alternatively be a tracer. The tracer may be a single compound, or two or more tracer compounds from the same or different classes of compounds. In some embodiments, the tracer is present in the composition at a total concentration of about 1 parts per million (ppm) to about 5000 ppm by weight, based on the weight of the entire composition. In other embodiments, the tracer is present at a total concentration of about 10 ppm to about 1000 ppm. In other embodiments, the tracer is present at a total concentration of about 20 ppm to about 500 ppm. In other embodiments, the tracer is present at a total concentration of about 25 ppm to about 500 ppm. In other embodiments, the tracer is present at a total concentration of about 50 ppm to about 500 ppm. Alternatively, the tracer is present at a total concentration of about 100 ppm to about 300 ppm.

[0055] The tracer may be selected from the group consisting of hydrofluorocarbons (HFCs), deuterated hydrofluorocarbons, chlorofluorocarbons (CFCs), hydrofluorochlorocarbons (HCFCs), hydrofluoroolefins (HFOs), chlorocarbons, perfluorocarbons, fluoroethers, brominated compounds, iodate compounds, alcohols, aldehydes and ketones, nitrous oxide, and combinations thereof. Alternatively, the tracer may be selected from the group consisting of trifluoromethane (HFC-23), 1,1,1,3-tetrafluoropropene (HFO-1234ze, cis or trans), 3,3,3-trifluoropropene (HFO-1243zf), 1,2,3,3,3-pentafluoropropene (HFO-1225ye, E or Z isomer), dichlorodifluoromethane (CFC-12), chlorodifluoromethane (HCFC-22), methyl chloride (R-4 0), chlorofluoromethane (HCFC-31), fluoroethane (HFC-161), 1,1,1-trifluoroethane (HFC-143a), chloropentafluoroethane (CFC-115), 1,2-dichloro-1,1,2,2-tetrafluoroethane (CFC-114), 1,1-dichloro-1,2,2,2-tetrafluoroethane (CFC-114a), 2-chloro-1,1,1,2-tetrafluoroethane (HCF C-124), Pentafluoroethane (HFC-125), 1,1,2,2-Tetrafluoroethane (HFC-134), 1,1,1,2-Tetrafluoroethane (HFC-134a), 1,1,1,3,3,3-Hexafluoropropane (HFC-236fa), 1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea), 1,1,1,2,2,3,3-Heptafluoropropane (HFC-227ea) , 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,2,2-pentafluoropropane (HFC-245cb), 1,1,1,2,3-pentafluoropropane (HFC-245eb), 1,1,2,2-tetrafluoropropane (HFC-254cb), 1,1,1,2-tetrafluoropropane (HFC-254eb), 1,1,1-trifluoropropane (HFC-263fb), 1,The iodotrifluoromethane may be selected from the group consisting of 1-difluoro-2-chloroethylene (HCFC-1122), 2-chloro-1,1,2-trifluoroethylene (CFC-1113), 1,1,1,3,3-pentafluorobutane (HFC-365mfc), 1,1,1,2,3,4,4,5,5,5-decafluoropentane (HFC-43-10mee), 1,1,1,2,2,3,4,5,5,6,6,7,7,7-tetradecafluoroheptane, hexafluorobutadiene, 3,3,3-trifluoropropyne, iodotrifluoromethane, deuterated hydrocarbons, deuterated hydrofluorocarbons, perfluorocarbons, fluoroethers, brominated compounds, iodinated compounds, alcohols, aldehydes, ketones, nitrous oxide (NO), and mixtures thereof. In some embodiments, the tracer is a blend containing two or more hydrofluorocarbons, or one hydrofluorocarbon in combination with one or more perfluorocarbons. In other embodiments, the tracer is a blend of at least one CFC and at least one HCFC, HFC, or PFC.

[0056] Tracers may be added to the compositions of the present invention in predetermined amounts to allow for the detection of any dilution, adulteration, or other alteration of the composition. Tracers may also allow for the detection of products that infringe existing patent rights by identifying the patentee's product against competing infringing products. Furthermore, in one embodiment, the tracer compound may allow for the detection of the manufacturing process by which the product is produced.

[0057] In some embodiments, an optional surge tank or accumulator 150 may be inserted between the evaporator 120 and the compressor 140 to prevent liquid refrigerant and / or lubricant from entering the compressor 140. If present, the surge tank 150 may return accumulated liquid to the evaporator 120.

[0058] In an alternative embodiment, the refrigeration system may be a flooded evaporative refrigeration system 200. Figure 2 illustrates the flooded evaporative refrigeration system 200. In the example of Figure 2, the elements of the system are the same as those described above for the direct expansion refrigeration system 100, except that the capillary tube 125 is absent and an optional pump 225 may be present to assist in the movement of refrigerant from the receiving tank 110 to the flooded evaporator 220. If present, the surge tank 150 may return accumulated liquid to the receiving tank 110 and provide it again to the evaporator 220. The operative connection from the condenser 160 to the receiving tank 110 further includes an expansion valve 270.

[0059] The performance of the refrigerant compositions of the present invention compared to R-457A, R-454C, R-404A, and other refrigerants is illustrated in the following examples. [Example]

[0060] Example 1 Refrigeration performance The refrigeration performance of the compositions of the present invention was compared to R-404A (a mixture of 44 wt.% HFC-125 (pentafluoroethane), 52 wt.% HFC-143a (1,1,1-trifluoroethane), and 4 wt.% HFC-134a (1,1,1,2-tetrafluoroethane)), R-290 (propane), R-454C (a mixture containing 21.5 wt.% HFC-32 and 78.5 wt.% HFO-1234yf), R-457A (a mixture containing 18 wt.% HFC-32, 70 wt.% HFO-1234yf, and 12 wt.% HFC-152a (1,1-difluoroethane)), and R-507A (a mixture containing 50 wt.% HFC-125 and 50 wt.% HFC-143a). Performance was determined under both low and medium temperature refrigeration conditions.

[0061] [Table 2]

[0062] [Table 3]

[0063] [Table 4]

[0064] [Table 5]

[0065] [Table 6]

[0066] [Table 7]

[0067] The results show that the compositions of the present invention exhibit lower compressor discharge temperatures than R-454C and R-457A. They also have capacity and energy efficiency (COP) values ​​that are equal to or greater than those of existing refrigerants, particularly R-457A.

[0068] Example 2 Comparative refrigeration performance The refrigeration performance of the compositions of the present invention and comparative compositions was determined and compared to R-457A. Performance was determined under both low temperature (Table 5) and medium temperature (Table 6) refrigeration conditions as described in Example 1.

[0069] Low temperature refrigeration data:

[0070] [Table 8]

[0071] Data for medium temperature refrigeration conditions:

[0072] [Table 9]

[0073] Example 3 Differential analysis Fractionation analysis was performed on a composition containing 18 wt% R-32, 80 wt% R-1234yf, and 2.0 wt% propane (R-290) at multiple conditions to simulate fractionation at multiple temperatures during storage and / or shipping and within the facility as a result of refrigerant use and refilling, as required by ASHRAE Standard 34. This data is used to determine the worst case of fractionation for flammability (WCFF), or the composition with the highest level of propane.

[0074] Leakage Data at Storage / Shipping Conditions (Tables 7, 8, and 9)

[0075] [Table 10] * 5.67 mass percent is the maximum % of R-290 in the gas phase for all conditions tested.

[0076] [Table 11]

[0077] [Table 12]

[0078] Equipment leakage data (Tables 10, 11, and 12).

[0079] [Table 13]

[0080] [Table 14]

[0081] [Table 15]

[0082] Leak / Refill Test Data (Table 13)

[0083] [Table 16]

[0084] WCFF is identified as a composition containing 5.67% by weight of propane. This composition is estimated to have a burning velocity of greater than 10 cm / sec.

[0085] Example 4 Flammability classification: Vapor Leak Analysis and Flammability Testing The compositions of the present invention were evaluated under vapor leak conditions as described in ASHRAE Standard 34-2019, "Designation and Safety Classification of Refrigerants," to determine whether they could meet the requirements for ASHRAE Class 2L low flammability or Class 2 flammability. Nominal formulations are developed by design, and therefore, representative manufacturing tolerances are assigned since the exact composition is not manufactured in commercial practice. The manufacturing tolerances selected for this analysis were as follows: ±2 wt% R-32, ±2 wt% R-1234yf, and +0 / -0.5 wt% R-290. The Worst Case Formulation for Flammability (WCF) was selected, which, in these cases, exhibited the highest burning rate (S) based on the manufacturing tolerances. u) represents a composition that can produce a refrigerant vapor leak. The WCF was then modeled using NIST RefLeak 6.0 for the worst-case conditions of several ASHRAE Standard 34 leak scenarios to determine the most flammable mixture composition (WCFF), where the highest concentrations of the higher burning rate components (R-290 and R-32) are observed in either the liquid or vapor phase of the refrigerant. For the compositions of the present invention, WCFF was determined to occur during "leak under storage / shipment" conditions. WCFF was found to be in the vapor phase at bubble point temperature +10°C before the onset of leakage when the cylinder was filled to 90% full at a temperature of 54.4°C. The WCFF compositions were then tested using a vertical tube burning velocity instrument. The results of the tested compositions, shown in Table 14 herein, were found to have a burning velocity of 10 cm / sec or less. As such, they are expected to be classified in the A2L safety category.

[0086] [Table 17]

[0087] Thus, the compositions of the present invention can provide lower compressor discharge temperatures while maintaining a safety classification from ASHRAE of A2L.

[0088] While the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that various changes can be made and equivalents can be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is not intended that the invention be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but rather, the invention is intended to include all embodiments falling within the scope of the appended claims.

[0089] Additional Embodiments Embodiment A1: A composition comprising a refrigerant consisting essentially of difluoromethane (R-32), 2,3,3,3-tetrafluoropropene (R-1234yf), and propane.

[0090] Embodiment A2: The composition of Embodiment A1 wherein the difluoromethane (R-32) is present in an amount from 15 to less than 20 wt.% based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount from 74 to greater than 84 wt.% based on the weight of the refrigerant composition, and the propane (R-290) is present in an amount from 1.0 to 10 wt.% based on the weight of the refrigerant composition.

[0091] Embodiment A3: The composition of Embodiment A1 or A2, wherein the difluoromethane (R-32) is present in an amount from 16 to less than 19 wt.%, based on the weight of the refrigerant composition; the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount from 76 to greater than 84 wt.%, based on the weight of the refrigerant composition; and the propane (R-290) is present in an amount from 1.0 to 5.0 wt.%, based on the weight of the refrigerant composition.

[0092] Embodiment A4: The composition of any one of Embodiments A1 to A3, wherein the difluoromethane (R-32) is present in an amount from 16 to 18 wt.%, based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount from 79 to 83 wt.%, based on the weight of the refrigerant composition, and the propane is present in an amount from 1.0 to 4.0 wt.%, based on the weight of the refrigerant composition.

[0093] Embodiment A5: The composition of any one of Embodiments A1 to A4, wherein the propane is present in an amount of 2.0 to 3.0 wt. %, or preferably 0.5 to 1.0 wt. %, based on the weight of the refrigerant composition.

[0094] Embodiment A6: The composition of any one of Embodiments A1 to A5, wherein the difluoromethane (R-32) is present in an amount from 17 to 18 wt.%, based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount from 80 to 82 wt.%, based on the weight of the refrigerant composition, and the propane is present in an amount from 1.0 to 2.0 wt.%, based on the weight of the refrigerant composition.

[0095] Embodiment A7: The composition of any one of Embodiments A1 through A6, wherein the difluoromethane (R-32) is present in an amount of 18 wt.% based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount of 80 wt.% based on the weight of the refrigerant composition, and the propane is present in an amount of 2.0 wt.% based on the weight of the refrigerant composition.

[0096] Embodiment A8: The composition of any one of Embodiments A1 through A6, wherein the difluoromethane (R-32) is present in an amount of 17% by weight based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount of 81% by weight based on the weight of the refrigerant composition, and the propane is present in an amount of 2.0% by weight based on the weight of the refrigerant composition.

[0097] Embodiment A9: The composition of any one of Embodiments A1 through A6, wherein the difluoromethane (R-32) is present in an amount of 18% by weight based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount of 81% by weight based on the weight of the refrigerant composition, and the propane is present in an amount of 1.0% by weight based on the weight of the refrigerant composition.

[0098] Embodiment A10: The composition of any one of Embodiments A1 through A6, wherein the difluoromethane (R-32) is present in an amount of 17% by weight based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount of 82% by weight based on the weight of the refrigerant composition, and the propane is present in an amount of 1.0% by weight based on the weight of the refrigerant composition.

[0099] Embodiment A11: The composition of any one of Embodiments A1 to A10 further comprising a non-refrigerant compound in an amount from 0.01 to 49% by weight, based on the weight of the refrigerant composition.

[0100] Embodiment A12: The composition of any one of Embodiments A1-A11, wherein the non-refrigerant compound comprises a lubricant selected from the group consisting of mineral oil, alkylbenzene, polyol ester, polyalkylene glycol, polyvinyl ether, polycarbonate, perfluoropolyether, silicone, silicate ester, phosphate ester, paraffin, naphthene, polyalphaolefin, and combinations thereof.

[0101] Embodiment A13: The composition of any one of Embodiments A1-A12, wherein the non-refrigerant compound comprises at least one selected from the group consisting of dyes (including UV dyes), solubilizers, compatibilizers, stabilizers, tracers, antiwear agents, extreme pressure additives, corrosion and oxidation inhibitors, metal surface energy reducers, metal surface deactivators, free radical scavengers, foam control agents, viscosity index improvers, pour point depressants, detergents, viscosity modifiers, and mixtures thereof.

[0102] Embodiment A14: The composition of any one of Embodiments A1-A13, wherein the non-refrigerant compound comprises at least one stabilizer selected from the group consisting of hindered phenols, thiophosphates, butylated triphenyl phosphorothioate, organophosphates or phosphites, aryl alkyl ethers, terpenes, terpenoids, epoxides, fluorinated epoxides, oxetanes, ascorbic acid, thiols, lactones, thioethers, amines, nitromethane, alkyl silanes, benzophenone derivatives, aryl sulfides, divinyl terephthalic acid, diphenyl terephthalic acid, ionic liquids, and mixtures thereof.

[0103] Embodiment A15: The composition of any one of Embodiments A1 through A14, wherein the refrigerant composition has a burning velocity of less than 10 cm / sec.

[0104] Embodiment A16: The composition of any one of Embodiments A1-A15, wherein the refrigerant can be classified as 2L flammable by ASHRAE.

[0105] Embodiment A17: The composition of any one of Embodiments A1 to A16, wherein the difluoromethane (R-32) is present in an amount from 17 to 18 wt.%, based on the weight of the refrigerant composition, the 2,3,3,3-tetrafluoropropene (R-1234yf) is present in an amount from 81 to 82 wt.%, based on the weight of the refrigerant composition, and the propane is present in an amount of 1.0 wt.%, based on the weight of the refrigerant composition.

[0106] Embodiment B1: A refrigeration system comprising: A totally hermetic compressor, a refrigerant composition; Including, The refrigerant composition comprises a composition described in any one of embodiments A1 to A17. Refrigeration system.

[0107] Embodiment B2: The refrigeration system of embodiment B1, wherein the hermetic compressor is a rotary compressor, a scroll compressor, or a reciprocating compressor.

[0108] Embodiment B3: The refrigeration system of embodiment B1 or B2, wherein the hermetic compressor is a low back pressure (LBP) or medium back pressure (MBP) hermetic compressor.

[0109] Embodiment B4: The refrigeration system of any one of Embodiments B1 to B3, wherein the hermetic compressor is a low back pressure (LBP) hermetic reciprocating compressor.

[0110] Embodiment B5: The refrigeration system of any one of Embodiments B1 to B4, further comprising an evaporator, wherein the average evaporator temperature is less than -5°C.

[0111] Embodiment B6: The refrigeration system of any one of Embodiments B1-B5, wherein the compressor discharge temperature is less than the compressor discharge temperature of R-457A at the same operating conditions.

[0112] Embodiment B7: The refrigeration system of any one of Embodiments B1-B5, wherein the compressor discharge temperature is less than the compressor discharge temperature of R-454C at the same operating conditions.

[0113] Embodiment C1: A method of replacing a first refrigerant composition comprising R-404A, R-457A, R-290, or R-454C with a second refrigerant composition comprising the composition of any one of Embodiments A1 through A17, wherein the replacement is performed in a propane refrigeration system comprising a hermetic compressor.

[0114] Embodiment C2: A refrigeration system according to embodiment C1, wherein the hermetic compressor is a rotary compressor, a scroll compressor, or a reciprocating compressor.

[0115] Embodiment C3: The refrigeration system of embodiment C1 or C2, wherein the hermetic compressor is a low back pressure (LBP) or medium back pressure (MBP) hermetic compressor.

[0116] Embodiment C4: The refrigeration system of any one of Embodiments C1-C3, wherein the hermetic compressor is a low back pressure (LBP) hermetic reciprocating compressor.

[0117] Embodiment C5: The method of any one of Embodiments C1-C4, wherein the compressor discharge temperature is below the compressor discharge temperature of R-457A.

[0118] Embodiment C6: The method of any one of Embodiments C1-C4, wherein the compressor discharge temperature is below the compressor discharge temperature of R-454C.

[0119] Embodiment D1: A method of operating a hermetic compressor as part of a refrigeration system, comprising the steps of: receiving, by a hermetic compressor, a refrigerant composition comprising any one of the compositions of embodiments A1 to A17; compressing the refrigerant composition with a hermetic compressor; Including, The discharge temperature of the compressor is 80.0 ° C to 100.0 ° C. method.

[0120] Embodiment D2: The method of embodiment D1, wherein the hermetic compressor is a rotary compressor, a scroll compressor, or a reciprocating compressor.

[0121] Embodiment D3: The method of any one of Embodiments D1 or D2, wherein the hermetic compressor is a low back pressure (LBP) or medium back pressure (MBP) hermetic compressor.

[0122] Embodiment D4: The method of any one of Embodiments D1-D3, wherein the hermetic compressor is a low back pressure (LBP) hermetic reciprocating compressor.

[0123] Embodiment D5: The method of any one of Embodiments D1-D4, wherein the hermetic compressor receives the refrigerant composition from an evaporator having an average evaporator temperature of -40°C to -5°C.

[0124] Embodiment D6: The method of any one of Embodiments D1 through D54, wherein the hermetic compressor receives the refrigerant composition from an evaporator having an average evaporator temperature of from -40°C to -18°C.

[0125] Embodiment D7: The method of any one of Embodiments D1-D6, wherein the hermetic compressor receives the refrigerant composition from an evaporator having an average evaporator temperature of -20°C to -5°C.

Claims

1. A hermetic compressor; a refrigeration system comprising a refrigerant composition, The refrigerant composition is 1. A refrigeration system wherein difluoromethane (R-32) is present in an amount of 16 to 18 wt %, based on the weight of the refrigerant composition, 2,3,3,3-tetrafluoropropene is present in an amount of 79 to 83 wt %, based on the weight of the refrigerant composition, and propane is present in an amount of 1.0 to 4.0 wt %, based on the weight of the refrigerant composition.

2. 10. The refrigeration system of claim 1, further comprising a non-refrigerant compound in an amount of 0.01 to 49 weight percent based on the weight of the refrigerant composition.

3. 3. The refrigeration system of claim 2, wherein the non-refrigerant compound is selected from the group consisting of mineral oil, alkyl benzene, polyol ester, polyalkylene glycol, polyvinyl ether, polycarbonate, perfluoropolyether, silicone, silicate ester, phosphate ester, paraffin, naphthene, polyalphaolefin, and combinations thereof.

4. further comprising an evaporator; 10. The refrigeration system of claim 1, wherein the average temperature of the evaporator is less than -5°C.

5. 10. The refrigeration system of claim 1, wherein the compressor discharge temperature is lower than the compressor discharge temperature of R-457A under the same operating conditions.

6. 10. The refrigeration system of claim 1, wherein the compressor discharge temperature is lower than the compressor discharge temperature of R-454C under the same operating conditions.

7. 10. The refrigeration system of claim 1, wherein the refrigerant composition has a burning velocity of less than 10 cm / s.

8. 1. A method for replacing a first refrigerant composition comprising R-404A, R-457A, R-290, or R-454C with a second refrigerant composition comprising 79 to 83 weight percent 2,3,3,3-tetrafluoropropene, 16 to 18 weight percent difluoromethane, and 1.0 to 4.0 weight percent propane, wherein the replacement occurs in a refrigeration system including a hermetic compressor.

9. 1. A method of operating a hermetic compressor as part of a refrigeration system, comprising: receiving, by a hermetic compressor, a refrigerant composition comprising difluoromethane, 2333-tetrafluoropropene, and propane; compressing the refrigerant composition with a hermetic compressor; The discharge temperature of the compressor is 80.0°C to 100.0°C, The refrigerant composition is 1. A method according to claim 1, wherein difluoromethane (R-32) is present in an amount of 16 to 18 wt % based on the weight of the refrigerant composition, 2,3,3,3-tetrafluoropropene is present in an amount of 79 to 83 wt % based on the weight of the refrigerant composition, and propane is present in an amount of 1.0 to 4.0 wt % based on the weight of the refrigerant composition.

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