Conveying method, freezing method, freezing system, and hose for freezing system

Abstract

The invention provides a method capable of stably conveying fluoroethylene in a refrigeration system or an air conditioning system and a refrigeration method. The method for transporting a heat transfer fluid according to the present invention is for transporting a heat transfer fluid in a refrigeration system or an air conditioning system, and comprises a step for circulating the heat transfer fluid through one or more hoses of the system, the heat transfer fluid containing fluoroethylene, and the hoses being formed from a resin. According to the method for conveying the heat transfer fluid, fluoroethylene can be stably conveyed in a refrigeration system or an air conditioning system.

Description

Technical Field

[0001] The invention relates to a transportation method, a freezing method, a freezing system and a hose for the freezing system. Background Art

[0002] Patent Document 1 discloses a technique regarding the use of a flexible hose that can handle high-pressure fluid and provide a barrier against permeation loss in air conditioning and refrigeration systems.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-513827 Summary of the invention

[0006] Technical problem to be solved by the invention

[0007] An object of the present invention is to provide a method capable of stably conveying fluoroethylene in a refrigeration system or an air-conditioning system, a conveying method, a refrigeration method, a refrigeration system, and a hose for a refrigeration system.

[0008] Technical solutions for solving technical problems

[0009] That is, the present invention includes, for example, the subject matters described in the following items.

[0010] Item 1. A method for conveying a heat transfer fluid, which is used to convey a heat transfer fluid in a refrigeration system or an air conditioning system,

[0011] The method comprises a circulation step of circulating the heat transfer fluid through one or more hoses in the system.

[0012] The heat transfer fluid contains fluoroethylene,

[0013] The hose is formed of resin.

[0014] Item 2. The transport method according to Item 1, wherein the fluoroethylene comprises at least one selected from trifluoroethylene and 1,2-difluoroethylene.

[0015] Item 3. The transport method according to Item 2, wherein the fluoroethylene comprises E-isomer 1,2-difluoroethylene.

[0016] Item 4. The conveying method according to any one of Items 1 to 3, wherein the circulation step includes at least one step selected from the following steps:

[0017] The step of circulating the heat transfer fluid through the hose connected between the compressor outlet and the condenser inlet;

[0018] The step of circulating the heat transfer fluid through the hose connected between the condenser outlet and the evaporator inlet; and

[0019] The process of circulating the heat transfer fluid through the above-mentioned hose connected between the evaporator outlet and the compressor inlet.

[0020] Item 5. A freezing method comprising the step of freezing using the transportation method according to any one of Items 1 to 3.

[0021] Item 6. A refrigeration system having a hose for circulating a heat transfer fluid,

[0022] The heat transfer fluid contains fluoroethylene,

[0023] The hose is formed of resin.

[0024] Item 7. The refrigeration system according to Item 6, wherein the fluoroethylene is at least one selected from trifluoroethylene and 1,2-difluoroethylene.

[0025] Item 8. The refrigeration system according to Item 6, wherein the fluoroethylene includes E-isomer 1,2-difluoroethylene.

[0026] Item 9. A refrigeration system hose, which is used for the refrigeration system according to any one of Items 6 to 8.

[0027] Effects of the Invention

[0028] The transportation method of the present invention can stably transport fluoroethylene. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram showing an example of a cross section of a hose used in the transport method of the present invention.

[0030] Figure 2 This is a schematic diagram schematically showing a refrigeration system or an air-conditioning system using the heat transfer fluid transportation method of the present invention. DETAILED DESCRIPTION

[0031] Fluorinated vinyl represented by trans-1,2-difluoroethylene (hereinafter referred to as HFO-1132(E)) is highly anticipated as a new refrigerant. When such fluoroethylene is transported using hoses made of various materials, the compatibility and permeability of fluoroethylene to the hoses have not been studied at all. In other words, there is currently no method for stably transporting fluoroethylene in various systems such as refrigeration systems and air conditioning systems.

[0032] In view of such facts, the inventors of the present invention have repeatedly conducted intensive studies and, as a result, have found a method for stably conveying a heat transfer fluid containing fluoroethylene.

[0033] In the present invention, "stable transportation of heat transfer fluid (fluoroethylene)" includes: the refrigeration system and the hose for the refrigeration system can transport the heat transfer fluid without being damaged by the pressure of the heat transfer fluid (i.e., having pressure resistance); the refrigeration system and the hose for the refrigeration system can be transported without the materials used in the refrigeration system and the hose for the refrigeration system being degraded by the heat transfer fluid; and the heat transfer fluid can be transported while suppressing the penetration of the refrigeration system and the hose for the refrigeration system.

[0034] Hereinafter, the embodiments of the present invention will be described in detail. In this specification, the expressions "contain" and "include" include concepts such as "contain", "include", "consist essentially of", and "consist only of".

[0035] In this specification, the numerical range represented by "~" indicates a range including the numerical values ​​recorded before and after "~" as the minimum value and the maximum value, respectively. In the numerical range recorded in sections in this specification, the upper limit value or the lower limit value of the numerical range of a certain section can be arbitrarily combined with the upper limit value or the lower limit value of the numerical range of other sections. In the numerical range recorded in this specification, the upper limit value or the lower limit value of the numerical range can be replaced by the value shown in the embodiment or the value uniquely derived from the embodiment.

[0036] 1. Heat transfer fluid delivery method

[0037] The heat transfer fluid delivery method of the present invention is a method for delivering the heat transfer fluid in a refrigeration system or an air conditioning system, comprising the step of circulating the heat transfer fluid through one or more hoses in the system, wherein the heat transfer fluid contains fluoroethylene. The hose is preferably formed of a resin.

[0038] The heat transfer fluid conveying method of the present invention can suppress the loss of refrigerant when conveying the heat transfer fluid, and can stably convey the heat transfer fluid containing fluoroethylene.

[0039] (Heat transfer fluid)

[0040] The heat transfer fluid transported by the transport method of the present invention contains fluoroethylene. Fluoroethylene is an ethylene compound having at least one fluorine atom. The fluoroethylene contained in the heat transfer fluid preferably has at least two fluorine atom(s).

[0041] Among them, the fluoroethylene more preferably includes at least one selected from trifluoroethylene, 1,1-difluoroethylene and 1,2-difluoroethylene. From the perspective of easier and more stable transportation of fluoroethylene, the fluoroethylene further preferably includes 1,2-difluoroethylene. The fluoroethylene may consist of only at least one selected from trifluoroethylene, 1,1-difluoroethylene and 1,2-difluoroethylene, or may consist of only 1,2-difluoroethylene.

[0042] Such 1,2-difluoroethylene has two isomers (E-form and Z-form), specifically, trans-1,2-difluoroethylene (HFO-1132(E)) and cis-1,2-difluoroethylene (HFO-1132(Z)). In the present invention, 1,2-difluoroethylene may be only any one isomer or a mixture of the two isomers. In other words, the 1,2-difluoroethylene contained in the heat transfer fluid may be trans-1,2-difluoroethylene (HFO-1132(E)) and / or cis-1,2-difluoroethylene (HFO-1132(Z)).

[0043] Among them, 1,2-difluoroethylene preferably contains at least E-type 1,2-difluoroethylene, i.e., trans-1,2-difluoroethylene (HFO-1132(E)). More specifically, 1,2-difluoroethylene preferably contains 50% by mass or more of HFO-1132(E), more preferably 70% by mass or more, further preferably 80% by mass or more, and particularly preferably 90% by mass or more, relative to the total mass of 1,2-difluoroethylene. 1,2-difluoroethylene may also consist of only HFO-1132(E).

[0044] The heat transfer fluid may contain components other than fluoroethylene, for example, it may also contain refrigerants other than fluoroethylene. The so-called "refrigerants other than fluoroethylene" here at least include compounds marked with refrigerant numbers (ASHRAE numbers) beginning with R indicating the type of refrigerant as specified by ISO817 (International Organization for Standardization), and also include compounds that have the same properties as refrigerants as these although the refrigerant numbers are not marked. From the perspective of the structure of the compound, such refrigerants are roughly divided into "fluorocarbon compounds" and "non-fluorocarbon compounds". "Fluorocarbon compounds" include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). As "non-fluorocarbon compounds", propane (R290), propylene (R1270), butane (R600), isobutane (R600a), carbon dioxide (R744) and ammonia (R717) can be listed.

[0045] Examples of refrigerants other than fluoroethylene include 2,3,3,3-tetrafluoropropylene (HFO-1234yf), HFC-32, R290 (propane), R744 (carbon dioxide), R1234ze, pentafluoroethane (HFC-125), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1-trifluoroethane (HFC-143a), 1,1,2-trifluoroethane (HFC-143), 1,1-difluoroethane (HFC-152a), 1,2 - difluoroethane (HFC-152), fluoroethane (HFC-161), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), wherein the refrigerant other than fluoroethylene preferably contains at least one selected from HFC-32, HFC-152a, HFO-1234yf, R744 and R290. As one embodiment of the heat transfer fluid, a mixture containing the above-mentioned fluoroethylene, HFO-1234yf and / or HFC-32 can be cited.

[0046] When the heat transfer fluid contains HFO-1234yf, the content ratio thereof is not particularly limited. For example, the heat transfer fluid preferably contains 40% by mass or more of HFO-1234yf, more preferably 50% by mass or more, and further preferably 70% by mass or more, relative to the total mass of the fluoroethylene and HFO-1234yf. The heat transfer fluid preferably contains 90% by mass or less of HFO-1234yf, more preferably 85% by mass or less, relative to the total mass of the fluoroethylene and HFO-1234yf.

[0047] In the case where the heat transfer fluid also contains HFC-32, its content ratio is not particularly limited. For example, in the heat transfer fluid, relative to the total mass of the above-mentioned fluoroethylene, HFO-1234yf and HFC-32, the content ratio of HFC-32 is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 20% by mass or more. In the heat transfer fluid, relative to the total mass of the above-mentioned fluoroethylene, HFO-1234yf and HFC-32, the content ratio of HFC-32 is preferably 80% by mass or less, more preferably 50% by mass or less, further preferably 30% by mass or less, and particularly preferably 22% by mass or less.

[0048] The heat transfer fluid particularly preferably contains HFO-1132(E) and HFO-1234yf. The heat transfer fluid may also consist of only HFO-1132(E) and HFO-1234yf.

[0049] The manufacturing method of heat transfer fluid is not particularly limited, for example, known manufacturing methods can be widely adopted. For example, using fluoroethylene manufactured by known methods, heat transfer fluid can be obtained. In addition, when the heat transfer fluid contains HFO-1234yf, such HFO-1234yf can also be obtained by known methods. In addition, when the heat transfer fluid is a mixture of fluoroethylene and a refrigerant other than fluoroethylene, for example, by mixing the two in an appropriate mixing ratio, a heat transfer fluid can be obtained.

[0050] The heat transfer fluid may also contain components other than the refrigerant. As components other than the refrigerant, water, refrigeration oil, etc. can be cited. In the case where the heat transfer fluid contains components other than the refrigerant, the content ratio is not particularly limited. For example, relative to the total mass of the refrigerant in the heat transfer fluid, the content ratio of the components other than the refrigerant may be 10% by mass or less, preferably 5% by mass or less, and more preferably 3% by mass or less.

[0051] (hose)

[0052] In the transportation method of the present invention, the heat transfer fluid is transported through a hose. The material and structure used to form such a hose are not particularly limited, and for example, well-known hoses can be widely used. Among them, the above-mentioned hose used in the transportation method of the present invention is preferably formed of resin or metal, and more preferably formed of resin. In this case, fluoroethylene can be transported more stably. Examples of the resin include thermoplastic resins, thermosetting resins, and rubbers, and may contain two or more of these resins. That is, the hose may contain, for example, thermoplastic resins and rubber.

[0053] From the viewpoint of particularly easily suppressing the permeation of a heat transfer fluid containing fluoroethylene, the ethylene content (mol%) in the resin forming the hose is preferably 20 to 50 mol%, more preferably 20 to 30 mol%, relative to the total amount of the resin. The ethylene content in the resin can be measured based on the melting point of EVOH.

[0054] As one embodiment of the hose that can be used in the transportation method of the present invention, for example, there is a hose A having a core layer disclosed in Japanese Patent Application Laid-Open No. 2002-370273.

[0055] The hose A may be formed of a core layer (innermost layer) and a covering layer (outer layer) covering the core layer. A rubber layer (inner layer) may also be provided between the core layer (innermost layer) and the covering layer (outer layer). The core layer may be formed of, for example, various resins, specifically EVOH (Eval), polyamide resin, etc. The core layer may have a structure consisting of an inner core and an outer core arranged on the outer side, and such a structure may be formed, for example, by coextrusion. In this case, the inner core and the outer core may be formed of different resins. The rubber layer (inner layer) can be formed of various rubbers, for example, it can be formed of one or more rubber materials selected from nitrile-butadiene rubber (NBR), hydrogenated nitrile-butadiene rubber (HNBR), chlorosulfonated polyethylene rubber (CSM), ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR), chlorinated butyl rubber (Cl-IIR), brominated butyl rubber (Br-IIR), epichlorohydrin rubber (CHR, CHC), acrylic rubber (ACM) and chloroprene rubber (CR), among which butyl rubber (IIR) and ethylene propylene diene rubber (EPDM) are preferred.

[0056] In the above-mentioned hose A, the covering layer (outer layer) can be formed of one or more rubber materials selected from nitrile-butadiene rubber (NBR), hydrogenated nitrile-butadiene rubber (HNBR), chlorosulfonated polyethylene rubber (CSM), ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR), chlorinated butyl rubber (Cl-IIR), brominated butyl rubber (Br-IIR), epichlorohydrin rubber (CHR, CHC), acrylic rubber (ACM) and chloroprene rubber (CR).

[0057] Figure 1 This is a schematic explanatory diagram showing an example of a cross section of the hose A. Figure 1 The hose A shown has a core layer 10 and a cover layer 20 covering the core layer 10, and a rubber layer 30 is provided between the core layer 10 and the cover layer 20. Figure 1 As shown, the core layer 10 may be formed as described above to include the inner core 11 and the outer core 12 covering the inner core 11. Of course, the core layer 10 may also be formed of only one layer. A cavity 50 is formed inside the core layer 10.

[0058] The hose A may be formed of only the core layer and the cover layer (outer layer), or Figure 1As shown, as needed, the hose A may also be provided with the rubber layer (inner layer) between the core layer (innermost layer) and the covering layer (outer layer). Such a rubber layer (inner layer) is a so-called friction layer and / or a reinforcement layer. For example, the hose A may have the following structure: the core layer is covered by the friction layer, the friction layer is covered by the reinforcement layer, and the reinforcement layer is covered by the covering layer. A reinforcement layer may also be provided between the rubber layer (inner layer) and the covering layer (outer layer). The reinforcement layer is formed of resins such as polyethylene terephthalate (PET) and aramid resin. Among them, Figure 1 The reinforcement layer is omitted.

[0059] In the above-mentioned hose A, the above-mentioned friction layer can be formed of polymer materials such as polyisoprene, polybutadiene, copolymer of butadiene and acrylonitrile, copolymer of butadiene and styrene, polychloroprene, polybutadiene, ethylene-propylene copolymer, EPDM, such as ethylene-propylene-norbornene terpolymer, ethylene-propylene-1,4-hexadiene terpolymer, ethylene-propylene-dicyclopentadiene terpolymer, etc.

[0060] The reinforcement layer can be formed of a wide variety of materials used to reinforce hoses, such as various fibers. For example, the reinforcement layer can be formed by braiding, spirally winding, knitting, or spirally knitting yarns.

[0061] The hose A preferably has a core layer containing EVOH (Eval), and more preferably has a core layer formed of an inner core layer composed of polyamide 6 (PA6) and an outer core layer composed of EVOH covering the inner core. In this case, from the perspective of being able to further suppress the permeation of a heat transfer fluid containing fluoroethylene, fluoroethylene can be particularly stably transported, and in particular, the permeation of 1,2-difluoroethylene can be particularly significantly suppressed.

[0062] The type of EVOH (Eval) is not particularly limited, and a wide range of known EVOH (Eval) can be used.

[0063] From the viewpoint of more easily suppressing the permeation of the heat transfer fluid containing fluoroethylene, the free volume of EVOH (Eval) is preferably More preferably The free volume of EVOH (Eval) can be measured by using a positron annihilation method on an EVOH sheet formed into a sheet shape.

[0064] From the viewpoint of particularly easily suppressing the permeation of a heat transfer fluid containing fluoroethylene, the ethylene content (mol%) in EVOH (Eval) is preferably 20 to 50 mol%, more preferably 20 to 30 mol%, relative to the total amount of EVOH. The ethylene content in EVOH (Eval) can be measured based on the melting point of EVOH.

[0065] As for the hose A, for example, a hose composed of a core layer (innermost layer), a rubber layer (inner layer), a reinforcement layer and a covering layer (outer layer) stacked in this order can be cited (for example, "Hose Flexible High (92490-4BC0A)" manufactured by BRIDGESTONE). In addition, as for the hose A, a hose composed of a core layer (innermost layer) formed by an inner core and an outer core, a rubber layer (inner layer), a reinforcement layer and a covering layer (outer covering layer) stacked in this order can be cited (for example, manufactured by ContiTech).

[0066] As another embodiment of the hose A, it is particularly preferred that the hose A is composed of the following layers: a core layer (innermost layer) formed of an inner core composed of polyamide 6 (PA6) and an outer core composed of EVOH (Eval) covering the inner core, a rubber layer (inner layer) composed of butyl rubber (IIR) and ethylene propylene diene rubber (EPDM), a reinforcement layer composed of polyethylene terephthalate (PET), and a covering layer (outer layer) composed of butyl rubber (IIR) and ethylene propylene diene rubber (EPDM). In this case, it is easy to suppress the hose permeability of the heat transfer fluid containing fluoroethylene, and it is easy to transport the heat transfer fluid particularly stably.

[0067] In order to further suppress the amount of heat transfer fluid that permeates from the hose, it is preferable to reduce the free volume of the resin (polymer) constituting the hose. Examples of such resins include EVOH (Eval); polyamide resins such as PA6, PA66, Genestar (PA9T) of Kuraray Co., Ltd., ARLEN (PA6T) of Mitsui Chemicals, and Reny of Mitsubishi Gas Chemical. That is, the resin forming the hose is preferably at least one selected from EVOH (Eval) and polyamide resins. In particular, the core layer is preferably at least one selected from EVOH (Eval) and polyamide resins.

[0068] As a method for reducing the free volume of a resin, for example, a method for reducing the free volume of a polyamide resin, it is effective to enhance the intermolecular interaction and reduce the easy mobility of the molecule. As intermolecular interactions, dipole interactions, hydrogen bonds, London dispersion forces, etc. can be listed, among which it is effective to improve the π-π interaction as one of the London dispersion forces. As a structure having the above-mentioned π-π interaction, for example, polyamides having aromatic groups in the molecular chain can be listed. Aromatic groups can be located in the molecular structure of the amine component or in the molecular structure of the carboxylic acid component. As polyamides having aromatic groups in the molecular chain, Genestar (PA9T) of Kuraray Co., Ltd., ARLEN (PA6T) of Mitsui Chemicals, Reny of Mitsubishi Gas Chemical, etc. can be listed, and Genestar of Kuraray is particularly preferred.

[0069] Another embodiment of the hose that can be used in the transport method of the present invention is a hose B disclosed in Japanese Patent Application Laid-Open No. 2006-29443, which includes a rubber layer (inner layer), a reinforcement layer formed on the circumference thereof, and a covering layer (outer layer) further formed on the outer circumference of the reinforcement layer.

[0070] In the hose B, the rubber layer (inner layer) may be formed of a material containing (A) a rubber of at least one of butyl rubber and halogenated butyl rubber, (B) polybutene, and (C) a white filler. (C) The white filler is, for example, talc, mica, sericite, montmorillonite, silica, clay, and the like.

[0071] In the hose B, the reinforcement layer can be formed by, for example, braiding reinforcing wires such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), aramid, polyamide (nylon), vinylon, rayon, metal wire, etc. by spiral braiding, knitting braiding, or weaving braiding.

[0072] In the hose B, the covering layer (outer layer) may be formed of a material appropriately blended with a vulcanizing agent, carbon black, etc. in a rubber material such as butyl rubber (IIR), chlorinated butyl rubber (Cl-IIR), brominated butyl rubber (Br-IIR), acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), ethylene-propylene-diene rubber (EPDM), ethylene-propylene rubber (EPM), fluororubber (FKM), epichlorohydrin rubber (ECO), acrylic rubber, silicone rubber, chlorinated polyethylene rubber (CPE), polyurethane rubber, etc. In addition, as the outer layer, a thermoplastic elastomer (TPE) such as acrylic, styrene, olefin, diene, vinyl chloride, polyurethane, ester, amide, fluorine, silicone, etc., a heat shrink tube, etc. may be used.

[0073] As another embodiment of the hose that can be used in the transport method of the present invention, for example, there is a hose C disclosed in International Publication No. 2017 / 010335 that includes a rubber layer (inner layer), a reinforcement layer, and a cover layer (outer layer) in this order.

[0074] In the hose C, the rubber layer (inner layer) is preferably formed of a rubber composition containing a rubber component including at least one selected from chlorosulfonated polyethylene rubber, butyl rubber and chlorinated polyethylene rubber, and liquid butyl rubber.

[0075] In the hose C, the reinforcing layer may be formed of a fiber material such as polyester fiber, polyamide fiber, aramid fiber, vinylon fiber, rayon fiber, polyphenylene benzobisoxazole fiber, polyketone fiber, polyacrylate fiber, polyketone fiber, or a metal material such as a hard steel wire (such as, etc.) plated with brass or zinc plated. The shape of the reinforcing layer may be, for example, a sheet or a spiral.

[0076] In the hose C, the cover layer (outer layer) may be formed of, for example, styrene butadiene rubber, chloroprene rubber-based rubber, or ethylene propylene diene rubber.

[0077] In the transport method of the present invention, when two or more hoses are used, the hoses may be all the same, or may be partially or entirely different.

[0078] The heat transfer fluid transport method of the present invention includes a circulation step of circulating the heat transfer fluid through one or more of the hoses. The heat transfer fluid transport method of the present invention is not particularly limited as long as it includes such a circulation step.

[0079] The circulation step may include at least one step selected from the following steps 1, 2, and 3.

[0080] Step 1: A step of circulating the heat transfer fluid through a hose connected between the compressor outlet and the condenser inlet.

[0081] Step 2: A step of circulating the heat transfer fluid through a hose connected between the condenser outlet and the evaporator inlet.

[0082] Step 3: A step of circulating the heat transfer fluid through a hose connected between the evaporator outlet and the compressor inlet.

[0083] For example, in the heat transfer fluid transportation method of the present invention, the circulation step may include step 1, step 2 and step 3 in sequence.

[0084] Figure 2is a schematic diagram schematically showing a method for conveying a heat transfer fluid including the above steps 1 to 3, and in particular, a schematic diagram schematically showing a refrigeration system or an air conditioning system. Figure 2 As shown, an evaporator 1 , a compressor 2 , a condenser 3 and an expansion device 4 may be included.

[0085] like Figure 2 As shown, the heat transfer fluid from the evaporator 1 flows into the inlet of the compressor 2 through the hose 6 and is then discharged. The types of the evaporator 1 and the compressor 2 are not particularly limited. For example, the known evaporators and compressors that can be used in the refrigeration system or the air conditioning system can also be used in the transportation method of the present invention.

[0086] The heat transfer fluid compressed by the compressor flows to the condenser 3 through the compressor outlet and the hose 6. A pressure regulating valve 5 can be appropriately provided in the hose 6. The compressed heat transfer fluid can condense in the condenser 3 and release heat. The condenser cleaning heat transfer fluid (liquid refrigerant) passes through the expansion device 4 and then through the hose 6, and in the case of cooling mode, flows to the evaporator 1 arranged in the passenger compartment. In the evaporator 1, the liquid refrigerant is vaporized and can provide cooling. In the heating mode, the refrigerant in a gaseous state compressed by the compressor 2 flows to the condenser 3 arranged in the passenger compartment. In the condenser 3, the refrigerant is liquefied and can provide warm air. In the heat transfer fluid transportation method of the present invention, the above-mentioned cycle is performed to construct a refrigeration system or an air-conditioning system.

[0087] The hose 6 is preferably the aforementioned hose A, hose B, hose C, etc. When two or more hoses are used, the hoses may be all the same or partially or completely different.

[0088] The heat transfer fluid conveying method of the present invention can be applied to various refrigeration systems or air conditioning systems, for example, can be applied to stationary refrigeration or air conditioning in buildings, etc., or mobile refrigeration or air conditioning in vehicles, etc.

[0089] (Freezing Method)

[0090] In addition, the method for conveying a heat transfer fluid of the present invention can also be applied to a freezing method. Therefore, the freezing method of the present invention may include a freezing step using the method for conveying a heat transfer fluid of the present invention. In other words, the freezing method of the present invention performs freezing by utilizing the heat transfer fluid conveyed by the conveying method of the present invention. Therefore, the freezing method of the present invention includes a circulation step of circulating the heat transfer fluid through one or more of the above-mentioned hoses, and the heat transfer fluid contains fluoroethylene. The freezing method of the present invention includes the conveying method of the present invention, and thus can suppress the loss of the refrigerant when conveying the heat transfer fluid, can stably convey the heat transfer fluid containing fluoroethylene, and thus can provide excellent freezing capacity.

[0091] 2. Device

[0092] The device of the present invention comprises one or more hoses and heat transfer fluid, and the heat transfer fluid is circulated through the hoses, wherein the heat transfer fluid contains fluoroethylene.

[0093] In the device of the present invention, the type of hose is not particularly limited, and for example, a wide range of known hoses can be used, such as hoses made of resin or metal, preferably a hose made of resin, among which the aforementioned hose A, hose B, hose C, etc. are more preferably used, and hose A is particularly preferred. When the device of the present invention uses two or more hoses, the hoses may be all the same, or may be partially or completely different.

[0094] The heat transfer fluid circulating in the device of the present invention is the same as the heat transfer fluid circulating in the aforementioned transport method of the present invention. Therefore, the fluoroethylene contained in the heat transfer fluid circulating in the device of the present invention more preferably includes at least one selected from trifluoroethylene and 1,2-difluoroethylene, and further preferably includes 1,2-difluoroethylene. The above-mentioned fluoroethylene may be composed of only at least one selected from trifluoroethylene and 1,2-difluoroethylene, or may be composed of only 1,2-difluoroethylene.

[0095] In addition, in the device of the present invention, 1,2-difluoroethylene also preferably contains trans-1,2-difluoroethylene (HFO-1132(E)). More specifically, 1,2-difluoroethylene preferably contains 50% by mass or more of HFO-1132(E), more preferably 70% by mass or more, further preferably 80% by mass or more, and particularly preferably 90% by mass or more, relative to the total mass of 1,2-difluoroethylene. 1,2-difluoroethylene may also consist of only HFO-1132(E).

[0096] In the device of the present invention, the heat transfer fluid may contain components other than fluoroethylene, and such components may be, for example, the same as the components other than fluoroethylene used in the transfer method of the present invention. Therefore, as refrigerants other than fluoroethylene, for example, 2,3,3,3-tetrafluoropropylene (HFO-1234yf), HFC-32, R290 (propane), R744 (carbon dioxide), R1234ze, pentafluoroethane (HFC-125), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1-trifluoroethane (HFC-143a), 1,1,2-trifluoroethane (HFC-143), 1,1-difluoroethane (HFC-152a), 1 ,2-difluoroethane (HFC-152), fluoroethane (HFC-161), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), wherein the refrigerant other than fluoroethylene preferably contains at least one selected from HFC-32, HFC-152a, HFO-1234yf, R744 and R290. As one embodiment of the heat transfer fluid, a mixture containing the above-mentioned fluoroethylene, HFO-1234yf and HFC-32 can be cited.

[0097] When the heat transfer fluid contains HFO-1234yf, the content ratio thereof is not particularly limited. For example, in the heat transfer fluid, HFO-1234yf is preferably 40% by mass or more, more preferably 50% by mass or more, and further preferably 70% by mass or more, relative to the total mass of the fluoroethylene and HFO-1234yf. In the thermal fluid, HFO-1234yf is preferably contained in an amount of 90% by mass or less, and more preferably 85% by mass or less, relative to the total mass of the fluoroethylene and HFO-1234yf.

[0098] In the case where the above-mentioned heat transfer fluid also contains HFC-32, its content ratio is not particularly limited. For example, in the heat transfer fluid, relative to the total mass of the above-mentioned fluoroethylene, HFO-1234yf and HFC-32, the content ratio of HFC-32 is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 20% by mass or more. In the heat transfer fluid, relative to the total mass of the above-mentioned fluoroethylene, HFO-1234yf and HFC-32, the content ratio of HFC-32 is preferably 80% by mass or less, more preferably 70% by mass or less, further preferably 60% by mass or less, and particularly preferably 50% by mass or less.

[0099] The heat transfer fluid particularly preferably contains HFO-1132(E) and HFO-1234yf. The heat transfer fluid may also consist of only HFO-1132(E) and HFO-1234yf.

[0100] By using the device of the present invention, the loss of refrigerant during the circulation of the heat transfer fluid containing fluoroethylene can be suppressed, and the fluoroethylene can be stably transported. Therefore, the device of the present invention can be suitably used in various refrigerators and various air conditioners, for example, it can be suitable for use in fixed refrigeration or air conditioning in buildings, etc., or mobile refrigeration or air conditioning in vehicles, etc.

[0101] 3. Refrigeration system and hoses for refrigeration system

[0102] The refrigeration system of the present invention has a hose for circulating a heat transfer fluid containing fluoroethylene.

[0103] The heat transfer fluid circulating in the refrigeration system of the present invention is the same as the heat transfer fluid circulating in the aforementioned transport method of the present invention. Therefore, the fluoroethylene contained in the heat transfer fluid circulating in the refrigeration system of the present invention more preferably includes at least one selected from trifluoroethylene and 1,2-difluoroethylene, and further preferably includes 1,2-difluoroethylene. The above-mentioned fluoroethylene can be composed of only at least one selected from trifluoroethylene and 1,2-difluoroethylene, and can also be composed of only 1,2-difluoroethylene.

[0104] In addition, in the refrigeration system of the present invention, 1,2-difluoroethylene also preferably contains trans-1,2-difluoroethylene (HFO-1132(E)). More specifically, with respect to 1,2-difluoroethylene, it is preferred that 50% by mass or more of HFO-1132(E) is contained relative to the total mass of 1,2-difluoroethylene, more preferably 70% by mass or more, further preferably 80% by mass or more, and particularly preferably 90% by mass or more is contained. 1,2-difluoroethylene may also be composed only of HFO-1132(E).

[0105] In the refrigeration system of the present invention, the heat transfer fluid may contain components other than fluoroethylene, and such components may be, for example, the same as the components other than fluoroethylene used in the transfer method of the present invention. Therefore, as refrigerants other than fluoroethylene, for example, 2,3,3,3-tetrafluoropropylene (HFO-1234yf), HFC-32, R290 (propane), R744 (carbon dioxide), R1234ze, pentafluoroethane (HFC-125), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1-trifluoroethane (HFC-143a), 1,1,2-trifluoroethane (HFC-143), 1,1-difluoroethane (HFC-152a), 1 ,2-difluoroethane (HFC-152), fluoroethane (HFC-161), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), wherein the refrigerant other than fluoroethylene preferably contains at least one selected from HFC-32, HFC-152a, HFO-1234yf, R744 and R290. As one embodiment of the heat transfer fluid, a mixture containing the above-mentioned fluoroethylene, HFO-1234yf and HFC-32 can be cited.

[0106] When the heat transfer fluid contains HFO-1234yf, the content ratio is not particularly limited. For example, in the heat transfer fluid, HFO-1234yf is preferably 40% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more relative to the total mass of the fluoroethylene and HFO-1234yf.

[0107] In the refrigeration system of the present invention, when the heat transfer fluid further contains HFC-32, the content ratio thereof is not particularly limited. For example, in the heat transfer fluid, the content ratio of HFC-32 is preferably 5% by mass or more, more preferably 10% by mass or more, and further preferably 20% by mass or more relative to the total mass of the fluoroethylene, HFO-1234yf and HFC-32.

[0108] In the refrigeration system of the present invention, the heat transfer fluid particularly preferably contains HFO-1132(E) and HFO-1234yf. The heat transfer fluid may also consist of only HFO-1132(E) and HFO-1234yf.

[0109] In the refrigeration system of the present invention, the material and structure of the hose are not particularly limited. For example, well-known hoses can be widely used, such as resin or metal hoses, preferably resin hoses. Among them, the aforementioned hose A, hose B, hose C, etc. are more preferably used, and hose A is particularly preferred.

[0110] The refrigeration system of the present invention can suppress the loss of refrigerant when the heat transfer fluid containing fluoroethylene is circulated, and can stably transport fluoroethylene. Therefore, the refrigeration system of the present invention can be suitably used in various refrigerators and various air conditioners, for example, it can be suitable for use in fixed refrigeration or air conditioning in buildings, etc., or mobile refrigeration or air conditioning in vehicles, etc.

[0111] The refrigeration system hose of the present invention includes the aforementioned hose A, hose B or hose C. Such a refrigeration system hose can be suitably used in the refrigeration system of the present invention. In addition, the refrigeration system hose of the present invention can be suitably used as a hose for conveying the above-mentioned heat transfer fluid containing fluoroethylene.

[0112] When defining the inventions included in the present invention, each configuration (property, structure, function, etc.) described in each embodiment of the present invention can be arbitrarily combined. That is, the present invention includes all the subjects, including all combinations of each configuration that can be combined as described in this specification.

[0113] Example

[0114] Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.

[0115] (Example 1)

[0116] The two ends of a hose ("Hose Flexible High (92490-4BC0A) manufactured by BRIDGESTONE") consisting of a core layer (innermost layer) composed of polyamide 6 (PA6), a rubber layer (inner layer) composed of butyl rubber (IIR) and ethylene propylene diene rubber (EPDM), a reinforcement layer composed of polyethylene terephthalate (PET), and a covering layer (outer layer) composed of butyl rubber (IIR) and ethylene propylene diene rubber (EPDM) were die-forged. One end of the hose was sealed and a valve was installed at the other end to produce a test hose. Referring to the steps outlined in standard SAE J3062, the hose penetration rate (kg / m 2 / year). In this test, a mixture of HFO-1132(E) and HFO-1234yf (containing 77% by mass of HFO-1234yf) is used as a heat transfer fluid, and such a heat transfer fluid is filled in a test hose at 80% of its capacity at 80°C. The test hose filled with the heat transfer fluid is placed in a constant temperature bath and maintained at 80°C for 25 days. The hose is taken out at prescribed intervals, and the weight at each time is measured. The reduction in the heat transfer fluid relative to the initial filling amount is taken as refrigerant loss. Finally, the weight is measured 5 times at intervals of more than 24 hours in the last stage of the test, i.e., the last 5 days of the test period. The total reduction in the last stage of the test is divided by the number of days in the period (5 days), and the resulting value is multiplied by the coefficient R determined by the following formula (a), and the hose permeation rate (kg / m 2 / Year).

[0117] Coefficient R = 365.24 / (π×D×L)(a)

[0118] In the above formula (a), 365.24 is the number of days in a year, D is the inner diameter (mm) of the hose used in the test, and L is the length (mm) of the rubber portion of the hose used in the test.

[0119] (Example 1A)

[0120] The inner core layer composed of polyamide 6 (PA6) and Eval (EVOH, ethylene content 27 mol%, free volume ), a rubber layer (innermost layer) composed of butyl rubber (IIR), a reinforcement layer composed of aramid fiber (AR) and a covering layer (outer covering layer) composed of ethylene propylene rubber (EPM) were laminated in this order (manufactured by ContiTech). Except for this, the hose penetration rate (kg / m 2 / Year).

[0121] (Reference Example 1)

[0122] The hose permeation rate (kg / m 2 / Year).

[0123] [Table 1]

[0124] Heat transfer fluid <![CDATA[Hose penetration rate (kg / m 2 / year)]]> Reference Example 1 HFO-1234yf 0.75 Example 1 HFO-1132(E) and HFO-1234yf 3.43

[0125] According to Table 1, even for a heat transfer fluid containing fluoroethylene (HFO-1132(E)), the hose permeation rate is small as in Example 1. In addition, in the hose used in Example 1A, the hose permeation rate is even smaller. Therefore, it can be seen that in the transportation of a heat transfer fluid containing fluoroethylene, by using the hose A, the refrigerant loss during transportation can be suppressed, and fluoroethylene can be stably transported.

[0126] (Evaluation of hose material stability)

[0127] (Examples 2 to 11)

[0128] The stability of each hose material was evaluated with reference to the steps outlined in the standard SAE J2670. An autoclave was used as a test container, and the container was filled with refrigeration oil, hose material, and heat transfer fluid for evaluation. In this test, ND-OIL 11 was used as the refrigeration oil. As the hose, the core layer (innermost layer) of the hose material was changed to EPDM in Examples 2 and 3, to IIR in Examples 4 and 5, to PA6 in Examples 6 and 7, and to HNBR in Examples 8 and 9. The same hose as in Example 1 was used. As a test piece (dumbbell-shaped) of the hose material, a No. 7 test piece of JIS K7139 with a thickness of 2 mm was used. As the heat transfer fluid, a mixture of HFO-1132 (E) and HFO-1234yf (containing 77% by mass of HFO-1234yf) or HFO-1234yf was used, and such a heat transfer fluid was filled in an autoclave at 150°C and an absolute pressure of 3 MPa. In Examples 2, 4, 6, 8, and 10, HFO-1234yf was used as the heat transfer fluid, and in Examples 3, 5, 7, 9, and 11, a mixture of HFO-1132 (E) and HFO-1234yf (containing 77% by mass of HFO-1234yf) was used as the heat transfer fluid. The autoclave filled with the heat transfer fluid was placed in a thermostatic bath and maintained at 150° C. for 720 hours (when the hose material was PA6, maintained for 200 hours). After the test, the test piece was taken out, and the weight, thickness, and fracture deformation were measured, and the change rate of these hose materials before and after the measurement was calculated.

[0129] [Table 2]

[0130] Table 2-1 (Hose material: EPDM)

[0131] EPDM Weight change rate (%) Thickness change rate (%) Fracture deformation change rate (%) Example 2 -3.9 -1.0 -47 Example 3 -3.8 -0.3 -47

[0132] Table 2-2 (Hose material: IIR)

[0133] IIR Weight change rate (%) Thickness change rate (%) Fracture deformation change rate (%) Example 4 5.4 0.6 -31 Example 5 5.1 3.3 -35

[0134] Table 2-3 (Hose material: PA6)

[0135] PA6 Weight change rate (%) Thickness change rate (%) Fracture deformation change rate (%) Example 6 -3.0 -1.3 -73 Example 7 -2.7 -1.7 -73

[0136] Table 2-4 (Hose material: HNBR)

[0137] HNBR Weight change rate (%) Thickness change rate (%) Fracture deformation change rate (%) Example 8 -3.1 -2.7 -29 Example 9 -3.0 -6.0 -27

[0138] Table 2-5 (Hose material: CR)

[0139] CR Weight change rate (%) Thickness change rate (%) Fracture deformation change rate (%) Example 10 -5.3 -3.0 -53 Embodiment 11 -4.3 -2.6 -55

[0140] As shown in Tables 2-1 to 2-5, based on the comparison of Examples 2 and 3, the comparison of Examples 4 and 5, the comparison of Examples 6 and 7, the comparison of Examples 8 and 9, and the comparison of Examples 10 and 11, it can be seen that the stability of each rubber material to HFO-1234yf, and the stability of each rubber material to the mixture of HFO-1132E and HFO-1234yf (weight change rate, thickness change rate, fracture deformation change rate) are equivalent.

Claims

1. A method for conveying a heat transfer fluid, characterized in that: This method is used to transport heat transfer fluids in refrigeration systems or air conditioning systems. The delivery method includes a circulation step of circulating the heat transfer fluid through one or more hoses in the system. The heat transfer fluid contains fluoroethylene, The hose is formed of resin.

2. The conveying method according to claim 1, characterized in that: The fluoroethylene includes at least one selected from trifluoroethylene and 1,2-difluoroethylene.

3. The conveying method according to claim 2, characterized in that: The fluorinated vinyl includes E-isomer 1,2-difluoroethylene.

4. The method for conveying according to any one of claims 1 to 3, characterized in that: The cycle process includes at least one process selected from the following processes: The step of circulating the heat transfer fluid through the hose connected between the compressor outlet and the condenser inlet; The step of circulating the heat transfer fluid through the hose connected between the condenser outlet and the evaporator inlet; and The process of circulating a heat transfer fluid through the hose connected between the evaporator outlet and the compressor inlet.

5. A freezing method, characterized in that: The method comprises the step of freezing by using the transportation method according to any one of claims 1 to 3.

6. A refrigeration system, characterized in that: The refrigeration system has hoses that circulate a heat transfer fluid. The heat transfer fluid contains fluoroethylene, The hose is formed of resin.

7. The refrigeration system according to claim 6, characterized in that: The fluoroethylene is at least one selected from trifluoroethylene and 1,2-difluoroethylene.

8. The refrigeration system according to claim 6, characterized in that: The fluorinated vinyl includes E-isomer 1,2-difluoroethylene.

9. A hose for a refrigeration system, characterized in that: The refrigeration system is used in any one of claims 6 to 8.

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