WO2019022138A1

WO2019022138A1 - Working medium for heat cycle, composition for heat cycle system, and heat cycle system

Info

Publication number: WO2019022138A1
Application number: PCT/JP2018/027902
Authority: WO
Inventors: 正人福島; 洋輝速水
Original assignee: Ａｇｃ株式会社
Priority date: 2017-07-26
Filing date: 2018-07-25
Publication date: 2019-01-31
Also published as: CN110869462A; JP7226623B2; JP7060017B2; JP2022087163A; JPWO2019022138A1

Abstract

Provided is a working medium for a heat cycle. The ODP and GWP of the working medium are low enough that the impact of the working medium on global warming is substantially suppressed. The working medium also has favorable cycle performance, e.g., refrigerating capacity, coefficient of performance (COP), etc. The working medium also has substantially suppressed combustibility and is therefore highly safe. A working medium that is for a heat cycle and includes HCFO-1224yd and HFO-1234ze(E). The working medium for a heat cycle is characterized in that the total HCFO-1224yd and HFO-1234ze(E) content thereof is at least 50 mass% and in that the ratio HCFO-1224yd:HFO-1234ze(E) is a prescribed ratio.

Description

Working medium for thermal cycling, composition for thermal cycling system and thermal cycling system

The present invention relates to a working fluid for thermal cycling, a composition for thermal cycling system including the same, and a thermal cycling system using the composition.

Conventionally, working media for heat cycle systems such as refrigerants for refrigerators, refrigerants for air conditioners, working media for power generation systems (waste heat recovery power generation etc), working media for latent heat transport devices (heat pipes etc), secondary cooling media etc. As chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) have been used. However, CFCs and HCFCs have been pointed out that the effect on the ozone layer existing in the stratosphere is pointed out, and in particular, CFCs have already been totally abolished in accordance with the Montreal Protocol due to their high ozone depletion potential (ODP). Complete elimination has been decided.

Therefore, instead of CFC and HCFC, hydrofluorocarbon (HFC), which has less influence on the ozone layer, has come to be used as a working medium for thermal cycling. On the other hand, HFC is considered to have a relatively high global warming potential (GWP) and a problem.

For example, trichlorofluoromethane (CFC-11) has conventionally been used as a working medium in centrifugal refrigerators used for cold water production plants for buildings, etc. for cooling and heating of buildings and the like. However, CFC-11 with an ODP of 1 and a GWP of 4750 has already been abolished, and as a working medium to replace it, the ODP is currently 0.02 with a GWP of 77, both of which are low 1,1- Dichloro-2,2,2-trifluoroethane (HCFC-123) is used. In addition, as HFCs having high GWP but having ODP of 0, 1,1,1,2-tetrafluoroethane (HFC-134a) having a GWP of 1430 or 1,1,1,3,3- having a GWP of 1030 Pentafluoropropane (HFC-245fa) and the like are also used as alternatives to CFC-11.

On the other hand, recently, hydrofluoroolefins (HFO), hydrochlorofluoroolefins (HCFO) and chlorofluoroolefins having carbon-carbon double bonds as working media with low influence on the ozone layer and low GWP Expectations are gathered at (CFO) etc. Since these working media have carbon-carbon double bonds, they are easily decomposed by OH radicals in the atmosphere. In the present specification, unless otherwise specified, saturated HFC is referred to as HFC and is used separately from HFO.

Among them, HCFO and CFO are compounds in which the flammability is suppressed because the ratio of halogen in one molecule is large, and are considered as a working medium in which the load on the environment is small and the flammability is suppressed. For example, Patent Document 1 describes a working medium using 1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd).

International Publication No. 2012/157763

Although the working medium using the above HCFO-1224yd has a low environmental load and a good cycle performance, a working medium with further improved cycle performance is required while the environmental load is low. As such a working medium, one which is maintained at a low level of combustibility and has no problem with safety is required.

Therefore, according to the present invention, the effects on global warming are sufficiently suppressed by sufficiently low ODP and GWP, and the cycle performance such as refrigeration capacity and coefficient of performance (COP) is good, and further, the combustibility is sufficient. An object of the present invention is to provide a working medium for reduced thermal cycling with high safety.

Another object of the present invention is to provide a composition for a thermal cycle system including such a working medium, as well as a thermal cycle system using the composition.

The present invention, made in view of the above, provides a working medium for thermal cycling, a composition for thermal cycling system, and a thermal cycling system having the following configuration.

[1] A working medium for thermal cycling comprising 1-chloro-2,3,3,3-tetrafluoropropene and (E) -1,3,3,3-tetrafluoropropene, the actuation for thermal cycling The total content of the 1-chloro-2,3,3,3-tetrafluoropropene and the 1,3,3,3-tetrafluoropropene contained in the medium is 50% by mass or more, and 1 The ratio represented by -chloro-2,3,3,3-tetrafluoropropene: (E) -1,3,3,3-tetrafluoropropene is from 20:80 to 99: 1 on a mass basis. A working fluid for thermal cycling characterized by
[2] A working medium for thermal cycling comprising 1-chloro-2,3,3,3-tetrafluoropropene and 2,3,3,3-tetrafluoropropene, wherein the working medium for thermal cycling is The total content of 1-chloro-2,3,3,3-tetrafluoropropene and 2,3,3,3-tetrafluoropropene contained is 50% by mass or more, and 1-chloro- 2,3,3,3-tetrafluoropropene: a thermal cycle characterized in that a ratio represented by 2,3,3,3-tetrafluoropropene is 30:70 to 99: 1 on a mass basis. Working medium.
[3] The above 1-chloro-2,3,3,3-tetrafluoropropene is (E) -1-chloro-2,3,3,3-tetrafluoropropene: (Z) -1-chloro-2 The working medium for thermal cycling according to [1] or [2], wherein the ratio represented by 3,3,3,3-tetrafluoropropene is 50:50 to 0.01: 99.99 on a mass basis.

[4] A composition for a thermal cycle system, comprising the thermal cycle working medium according to any one of [1] to [3].
[5] The composition for a thermal cycle system according to [4], which comprises a lubricating oil.
[6] The composition for a heat cycle system according to [4] or [5], which contains a stabilizer that suppresses the deterioration of the heat cycle working medium.

[7] A thermal cycle system using the composition for a thermal cycle system according to any one of [4] to [6].
[8] The heat cycle system according to [7], wherein the heat cycle system is a refrigeration / refrigerator, an air conditioner, a power generation system, a heat transport device, or a secondary cooler.
[9] The heat cycle system according to [7] or [8], wherein the heat cycle system is a centrifugal refrigerator.
[10] The thermal cycle system according to any one of [7] to [9], wherein the thermal cycle system is a low pressure centrifugal refrigerator.

ADVANTAGE OF THE INVENTION The working medium for thermal cycling and the composition for thermal cycling system of the present invention have excellent cycle performance and a working medium for thermal cycling in which the effect on global warming is sufficiently suppressed by sufficiently low ODP and GWP. And a composition for a heat cycle system can be provided. Furthermore, the working medium for thermal cycling and the composition for thermal cycling system have sufficiently suppressed flammability.

According to the thermal cycle system of the present invention, since the composition for the thermal cycle system of the present invention is used, the cycle performance is excellent, the environmental load can be reduced, and the combustibility is suppressed, thereby enhancing the safety. Can be

It is a schematic block diagram which shows an example of the thermal cycle system (refrigeration cycle system) of this invention. FIG. 2 is a cycle diagram in which a change in the state of a working medium for thermal cycling in the thermal cycling system of FIG. 1 is described on a pressure-enthalpy diagram.

Hereinafter, embodiments of the present invention will be described.
In the present specification, for halogenated hydrocarbons, the abbreviation of the compound is indicated in the parenthesis after the compound name, but in the present specification, the abbreviation is used in place of the compound name as necessary. In addition, the name of the compound having a geometric isomer and (E) attached to its abbreviation indicate E form (trans form) and (Z) indicate Z form (cis form). In the name of the compound, in the abbreviation, when the E form and the Z form are not specified, the name and the abbreviation mean a generic name including the E form, the Z form, and the mixture of the E form and the Z form.

In the present specification, the “thermal cycle system” is an operation in which a thermal cycle working medium (hereinafter, also simply referred to as a working medium) is supplied to the thermal cycle system to enable thermal cycle operation. A system comprising a medium and a system for thermal cycling. A “thermal cycle system” is a thermal cycle designed to allow heat exchange (heat cycle) between the working medium and other substances other than the working medium by circulating the working medium in the system. System for

<Working medium for thermal cycle>
As described above, the thermal cycle working medium according to the embodiment of the present invention is a mixture of specific working mediums in a predetermined ratio. Specifically, the following two working media can be mentioned.

First Working Medium for Thermal Cycle
The first working medium for thermal cycling of the present embodiment is 1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd) and (E) -1,3,3,3-tetrafluoropropene (HFO-1234ze (E)), and the total content of HCFO-1224yd and HFO-1234ze (E) contained in the working medium is 50% by mass or more, and HCFO-1224yd: HFO-1234ze ( The proportion represented by E) is from 20:80 to 99: 1 on a mass basis.

Second Working Medium for Thermal Cycle
The second working medium for thermal cycling of the present embodiment includes 1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd) and 2,3,3,3-tetrafluoropropene (HFO-1234yf) And the total content of HCFO-1224yd and HFO-1234yf in the working medium is 50% by mass or more, and the ratio represented by HCFO-1224yd: HFO-1234yf is on a mass basis. 30: 70-99: 1.

The working medium of these embodiments is used in combination with a system for thermal cycling. In addition, these working media may be combined with a compound other than the working media, and used in a thermal cycle system as a composition for a thermal cycling system including these working media.

Next, each component contained in the above-described working medium will be described.
(HCFO-1224yd)
HCFO-1224yd has halogen that suppresses flammability and a carbon-carbon double bond that is easily decomposed by OH radicals in the atmosphere, as described above, for the first and second thermal cycles. It is an essential component that is also included in the working medium.

The HCFO-1224yd contains geometric isomers of HCFO-1224yd (Z) and HCFO-1224yd (E), and the boiling point of HCFO-1224yd (Z) is 15 ° C., and the boiling point of HCFO-1224yd (E) Is 19 ° C. As for GWP, HCFO-1224yd (Z) and HCFO 1224yd (E) are both <1. The ODP is 0 for both HCFO-1224yd (Z) and HCFO-1224yd (E). HCFO-1224yd (Z) is more chemically stable than HCFO 1224yd (E).

In this specification, the notation “HCFO-1224yd” is HCFO-1224yd (Z) alone, HCFO-1224yd (E) alone, a mixture of HCFO-1224yd (Z) and HCFO-1224yd (E), It is interpreted as including any of
In the present embodiment, it is preferable that the ratio represented by HCFO-1224yd (E): HCFO 1224yd (Z) is 50:50 to 0: 100 on a mass basis, and HCFO-1224yd is purified. It is more preferable that it is 50: 50-0.001: 99.9999 from a relation with cost, it is still more preferable that it is 50: 50-0.01: 99.99, 20: 80-0.01 Particularly preferred is 99.99.

(HFO-1234ze (E))
HFO-1234ze (E) has a carbon-carbon double bond which is easily decomposed by OH radicals in the atmosphere and is used in combination with HCFO-1224yd to suppress the state of flammability. It can be a working medium for thermal cycling with good cycle performance while maintaining it. The boiling point of this HFO-1234ze (E) is -15 ° C., the GWP is <1, and the ODP is 0.

(HFO-1234yf)
HFO-1234yf has a carbon-carbon double bond which is easily decomposed by OH radicals in the atmosphere, and it is used in combination with HCFO-1224yd while maintaining the state of suppression of flammability. And a working medium for thermal cycling with good cycle performance. The boiling point of this HFO-1234yf is -29.4 ° C., the GWP is <1, and the ODP is 0.

The characteristics of HCFO-1224yd, HFO-1234ze (E) and HFO-1234yf as working media contained in the working fluid for thermal cycling of the present embodiment are shown in Table 1. Specifically, the characteristics shown here are the boiling point, the cycle performance, and the environmental load as compared with those of HCFO-1224yd (Z) alone.

(Cycle performance)
The cycle performance includes, for example, the coefficient of performance and the refrigeration capacity evaluated in the heat cycle system (refrigeration cycle system) shown in FIG. The coefficients of performance and refrigeration capacity of HCFO-1224yd (Z), HFO-1234ze (E) and HFO-1234yf are relative coefficient of performance and relative refrigeration capacity based on that of HCFO-1224yd (Z) alone (1.00) As shown in Table 1. The relative coefficient of performance and the relative refrigeration capacity indicate that the working medium having a cycle performance better as compared to HCFO-1224yd (Z), as the relative coefficient of performance is greater than 1.

(Environmental load)
Environmental impact is evaluated by ODP and GWP. ODP is a value shown in or measured according to the ozone layer protection method. GWP is a 100-year value shown in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (2007) or measured according to the method of the report. In the present specification, GWP refers to this value unless otherwise noted. In addition, GWP in the working medium which is a mixture is taken as the weighted average by the composition mass of each component.

From Table 1, HFO-1234ze (E) is extremely superior in refrigeration capacity as a working medium compared to HCFO-1224yd (Z) alone, is equivalent in coefficient of performance, and has environmental load such as GWP. Is small.

In addition, HFO-1234yf is very excellent in refrigeration capacity as a working medium, has almost the same coefficient of performance, and has a small environmental load such as GWP, as compared with HCFO-1224yd (Z) alone.

The working medium for thermal cycling of the present embodiment further improves cycle performance by containing HCFO-1224yd (Z) in any proportion of HFO-1234ze (E) or HFO-1234yf, and is combustible. It is a safe working medium with sufficiently reduced That is, the thermal cycle working medium of the present embodiment is a thermal cycle working medium having a further improved function with respect to HCFO-1224 yd (Z) conventionally used.

Here, when the working medium is a mixture containing a plurality of compounds as described above, it is necessary to consider a temperature gradient. The temperature gradient is an index for measuring the difference in composition between the liquid phase and the gas phase in the working medium of the mixture, for example, as the difference between the start temperature and the completion temperature of condensation in the condenser 12 of the refrigeration cycle system 10 shown in FIG. Indicated. The temperature gradient is zero for a single compound and an azeotropic mixture, and the temperature gradient is very near zero for a quasi-azeotropic mixture that exhibits near-azeotropic behavior (less change in gas-liquid composition) upon evaporation.

If the temperature gradient is large, for example, the possibility of frost formation increases due to the decrease of the inlet temperature in the evaporator, which is a problem. Furthermore, in the thermal cycle system, it is general to make the working medium flowing through the heat exchanger and the heat source fluid such as water and air into opposite flow in order to improve the heat exchange efficiency. Due to the small temperature difference of the heat source fluid, it is difficult to obtain an energy efficient thermal cycle system in the case of a non-azeotropic mixture with a large temperature gradient. For this reason, when using a mixture as a working medium, a working medium having a suitable temperature gradient is desired.

The mixture of HCFO-1224yd (Z) and HFO-1234ze (E) and the mixture of HCFO 1224yd (Z) and HFO-1234yf do not azeotrope in mixtures of any mixing ratio. That is, in these mixtures, mixtures of any mixing ratio are non-azeotropic mixtures.

Therefore, in the working fluid for thermal cycling of the present embodiment, when the above mixture is used, it is preferable to set the composition in consideration of the temperature gradient. The temperature gradient is, for example, preferably 14 ° C. or less, more preferably 13 ° C. or less, and still more preferably 12 ° C. or less.

In addition, since there is almost no change in environmental load such as GWP due to composition change in the above mixture, a mixture of HCFO-1224yd (Z) and HFO-1234ze (E), a mixture of HCFO 1224yd (Z) and HFO-1234yf The preferred composition may be selected mainly considering the balance between the cycle performance and the temperature gradient.

Moreover, as a preferable composition of the mixture of HCFO-1224yd (Z) and HFO-1234ze (E) in the working medium for thermal cycling of the present embodiment, HCFO is taken into consideration in consideration of the balance of the flammability, cycle performance and temperature gradient. The composition is such that the ratio of HCFO-1224yd (Z) is 20 to 99% by mass and the ratio of HFO-1234ze (E) is 80 to 1% by mass with respect to the total amount of -1224yd (Z) and HFO-1234ze (E) It can be mentioned. If the composition of HCFO-1224yd (Z) and HFO-1234ze (E) in the working medium is in the above-mentioned range, it is possible to sufficiently suppress the flammability while improving the cycle performance.

As the composition, furthermore, the proportion of HCFO-1224 yd (Z) is preferably 40 to 99% by mass, the proportion of HFO-1234ze (E) is preferably 60 to 1% by mass, and the proportion of HCFO 1224 yd (Z) is preferably 70 to 70 A proportion of 99% by mass and HFO-1234ze (E) is particularly preferably 30 to 1% by mass.

As a preferable composition of the mixture of HCFO-1224yd (Z) and HFO-1234yf in the working fluid for thermal cycling of the present embodiment, HCFO 1224yd (Z) is considered in consideration of the balance of the flammability, cycle performance and temperature gradient. The composition is such that the ratio of HCFO-1224yd (Z) is 30 to 99% by mass, and the ratio of HFO-1234yf is 70 to 1% by mass with respect to the total amount of HFO and 1234yf. If the composition of HCFO-1224yd (Z) and HFO-1234yf in the working medium is in the above-mentioned range, it is possible to sufficiently suppress the flammability while improving the cycle performance.

As the composition, furthermore, the proportion of HCFO-1224 yd (Z) is preferably 50 to 99% by mass, the proportion of HFO-1234yf is preferably 50 to 1% by mass, and the proportion of HCFO 1224 yd (Z) is 80 to 99% by mass The ratio of HFO-1234yf is particularly preferably 20 to 1% by mass.

In these mixtures, the total content of HCFO-1224yd (Z) and HFO-1234ze (E) or the total content of HCFO 1224yd (Z) and HFO-1234yf is at least 50% by mass, based on the total amount of the working medium. The total content is preferably 50% by mass or more, more preferably 70% by mass or more, and still more preferably 100% by mass with respect to the total amount of the working medium.

If the total content of HCFO-1224yd (Z) and HFO-1234ze (E) or the total content of HCFO 1224yd (Z) and HFO-1234yf is within the above range, while improving the cycle performance of the working medium, Flammability can be sufficiently suppressed. These working media also serve as thermal cycling working media with the preferred features of low environmental impact and minimal thermal gradient problems.

From the viewpoint of further improving the cycle performance of the working medium, the working medium for thermal cycling of the present embodiment preferably contains HCFO-1224yd (Z), HFO-1234ze (E), and HFO-1234yf. In this case, the proportion of HCFO-1224yd (Z) is 10 to 50% by mass, and the proportion of HFO-1234ze (E) is 40 to 40% of the total amount of HCFO-1224yd (Z), HFO-1234ze (E) and HFO-1234yf. The proportion of 80% by mass and HFO-1234yf is preferably 10 to 50% by mass.

(Evaluation method of cycle performance, flammability and temperature gradient)
The cycle performance (refrigerating capacity (Q), coefficient of performance (COP)), flammability and temperature gradient of the working medium for thermal cycling can be evaluated, for example, using a refrigeration cycle system whose schematic configuration is shown in FIG.

The refrigeration cycle system 10 shown in FIG. 1 cools and liquefies the working medium vapor B discharged from the compressor 11 by compressing the working medium vapor A into a high temperature and high pressure working medium vapor B and the working medium vapor B discharged from the compressor 11. A condenser 12 as a working medium C of low temperature and high pressure, an expansion valve 13 of expanding the working medium C discharged from the condenser 12 to a working medium D of low temperature and low pressure, and a working medium D discharged from the expansion valve 13 And a pump 15 for supplying the load fluid E to the evaporator 14 and a pump 16 for supplying the fluid F to the condenser 12. System.

In the refrigeration cycle system 10, the following cycles (i) to (iv) are repeated.
(I) The working medium vapor A discharged from the evaporator 14 is compressed by the compressor 11 to be a high temperature and high pressure working medium vapor B (hereinafter referred to as "AB process").
(Ii) The working medium vapor B discharged from the compressor 11 is cooled by the fluid F in the condenser 12 and liquefied to form a working medium C of low temperature and high pressure. At this time, the fluid F is heated to become fluid F ′ and discharged from the condenser 12 (hereinafter referred to as “BC process”).
(Iii) The working medium C discharged from the condenser 12 is expanded by the expansion valve 13 to form a low-temperature low-pressure working medium D (hereinafter referred to as "CD process").
(Iv) The working medium D discharged from the expansion valve 13 is heated by the load fluid E in the evaporator 14 to be a high-temperature low-pressure working medium vapor A. At this time, the load fluid E is cooled to be a load fluid E ′ and discharged from the evaporator 14 (hereinafter referred to as “DA process”).

The refrigeration cycle system 10 is a cycle system consisting of adiabatic and isentropic changes, isenthalpy changes and isobaric changes. The change in state of the working medium can be represented as a trapezoid with vertices A, B, C, and D, when it is described on the pressure-enthalpy line (curve) diagram shown in FIG.

The AB process is a process in which adiabatic compression is performed by the compressor 11 to make the high temperature and low pressure working medium vapor A into a high temperature and high pressure working medium vapor B, which is shown by an AB line in FIG. As described later, the working medium vapor A is introduced into the compressor 11 in a superheated state, and the resulting working medium vapor B is also a superheated vapor.

The discharge pressure is the pressure (Px) in the state of B in FIG. 2 and is the maximum pressure in the refrigeration cycle. Further, the temperature (Tx) in the state of B in FIG. 2 is the discharge temperature, which is the maximum temperature in the refrigeration cycle. As described below, since the BC process is isobaric cooling, the discharge pressure has the same value as the condensation pressure. Therefore, in FIG. 2, the condensation pressure is indicated as Px for convenience.

The BC process is a process of performing isobaric cooling in the condenser 12 and making the high temperature / high pressure working medium vapor B into a low temperature / high pressure working medium C, and is shown by a BC line in FIG. The pressure at this time is the condensation pressure. Pressure - an intersection T ₁ of the high enthalpy side condensing temperature of the intersection of the enthalpy and BC line, the low enthalpy side intersection T ₂ is the condensation boiling temperature. Here, the temperature gradient when the working medium is a non-azeotropic mixture medium is shown as the difference between T ₁ and T ₂ .

The CD process is a process in which isenthalpy expansion is performed by the expansion valve 13 to make the working medium C of low temperature and high pressure into the working medium D of low temperature and low pressure, which is shown by a CD line in FIG. Incidentally, if Shimese the temperature in the working medium C of low temperature and high pressure at _{T _{_3,} T} 2 -T ₃ is (i) ~ supercooling degree of the working medium in the cycle of (iv) (SC).

The DA process is a process in which isobaric heating is performed by the evaporator 14 to return the low-temperature low-pressure working medium D to the high-temperature low-pressure working medium vapor A, which is shown by a DA line in FIG. The pressure at this time is the evaporation pressure. Pressure - intersection T ₆ of the high enthalpy side of the intersection of the enthalpy and DA line is evaporating temperature. If Shimese the temperature of the working medium vapor A in _{T _7, T 7} -T ₆ is (i) ~ superheat of the working medium in the cycle of (iv) (SH). Incidentally, _{T 4} denotes the temperature of the working medium D.

The refrigeration capacity (Q) and coefficient of performance (COP) of the working medium are the working medium A (evaporated, high temperature and low pressure after evaporation), B (high pressure and high temperature after compression), C (low temperature and high pressure after condensation), D (after expansion each enthalpy in each state of low temperature and low _{_{_{pressure), h a, h B,}}} h C, the use of _{h D,} the following formula (a), obtained from each of (B). At this time, there is no loss due to equipment efficiency, and no pressure loss in piping and heat exchangers.

The thermodynamic properties required to calculate the cycle performance of the working medium can be calculated based on the generalized equation of state (Soave-Redlich-Kwong equation) based on the corresponding state principle, and thermodynamic relations. If the characteristic value can not be obtained, calculation is performed using an estimation method based on the group contribution method.

Q = h _A -h _D (A)
COP = Q / compression work = (h _A −h _D ) / (h _B −h _A ) (B)

The compression work indicated by (h _B -h _A ) corresponds to the output (kW) of the refrigeration cycle, and the Q shown by (h _A -h _D ) above is required to operate the compressor, for example The amount of power corresponds to the consumed power (kW). Also, Q means the ability to freeze the load fluid, and a higher Q means more work can be done in the same system. In other words, if it has a large Q, it indicates that the desired performance can be obtained with a small amount of working medium, and the system can be miniaturized.

In addition, although the numerical values in Table 1 are also based on the above calculation method, the temperature conditions of the refrigeration cycle at this time are based on the numerical values at the time of evaluation at the following temperatures.

Evaporation temperature; 5 ° C (average temperature of evaporation start temperature and evaporation completion temperature)
Condensation completion temperature; 40 ° C (average temperature of condensation start temperature and condensation completion temperature)
Degree of supercooling (SC); 5 ° C
Degree of superheat (SH); 0 ° C
Compressor efficiency: 0.8

(Optional ingredient)
The working fluid for thermal cycling of the present embodiment includes, in addition to HCFO-1224yd and HFO-1234ze (E) or HCFO-1224yd and HFO-1234yf, known compounds used as working fluid as compared to the total amount of working fluid for thermal cycling. You may contain arbitrarily in the ratio of 50 mass% or less. When such a compound (optional component) is contained, the ratio of the compound (optional component) to the total amount of the working medium is preferably 30% by mass or less, more preferably 20% by mass or less, and particularly 10% by mass or less Preferably, 5% by mass or less is the most preferable.

As optional components, for example, HFO other than HFC, HFO-1234ze (E) and HFO-1234yf (hereinafter, also referred to as "other HFO"), HCFO other than HCFO-1224yd (hereinafter, "other HCFO" Working media such as trans-1,2-dichloroethylene and the like.

When the optional component is combined with a mixture of HCFO-1224yd and HFO-1234ze (E) or a mixture of HCFO-1224yd and HFO-1234yf to form a working medium, it has an action to further enhance cycle performance, such as GWP etc. It is preferable to be selected from the viewpoint of being able to sufficiently secure the safety such that the environmental load is limited to an acceptable range and the combustibility is not improved.

(HFC)
HFC is known to have a higher GWP than HCFO-1224yd, HFO-1234ze (E), and HFO-1234yf. Therefore, as an HFC combined with a mixture of HCFO-1224yd and HFO-1234ze (E) or a mixture of HCFO-1224yd and HFO-1234yf, environmental loads such as GWP, etc. can be made particularly acceptable when used as a working medium. It is preferable to be selected appropriately, keeping in mind that it is limited.

Specifically, an HFC having 1 to 5 carbon atoms is preferable as the HFC having a small environmental load such as GWP. The HFC may be linear, branched or cyclic.

As HFC, difluoromethane, difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, pentafluoropropane, hexafluoropropane, heptafluoropropane, pentafluorobutane, heptafluorocyclopentane and the like can be mentioned.

Among these, 1,1,2,2-tetrafluoroethane, HFC-134a, HFC-245fa and 1,1,1,3,3-pentafluorobutane (HFC-365mfc) are more preferable, and HFC-134a is more preferable. , HFC-245fa and HFC-365mfc are more preferable. One of HFCs may be used alone, or two or more thereof may be used in combination.

(HFO)
If HFO is other than HFO-1234ze (E) and HFO-1234yf, GWP is orders of magnitude lower than HFC. Therefore, it is preferable to appropriately select other HFOs from the point of view that safety can be ensured without improving the cycle performance as the working medium and the combustibility, rather than considering GWP.

Other HFOs include HFO-1336mzz (Z), HFO-1336mzz (E), 1,2-difluoroethylene (HFO-1132), 2-fluoropropene (HFO-1261yf), 1,1,2-trifluoro Propene (HFO-1243yc), (E) -1,2,3,3,3-pentafluoropropene (HFO-1225ye (E)), (Z) -1,2,3,3,3-pentafluoropropene (HFO-1225ye (Z)), (Z) -1,3,3,3-tetrafluoropropene (HFO-1234ze (Z)), 3,3,3-trifluoropropene (HFO-1243zf). .

As other HFOs, HFO-1234ze (Z) and HFO-1243zf are preferable. The other HFO may be used alone or in combination of two or more. By the way, the boiling point of HFO-1234ze (Z) is 9.7 ° C., GWP is <1, and ODP is 0.

(HCFO)
As HCFO, 1-chloro-2,2-difluoroethylene (HCFO-1122), 1,2-dichlorofluoroethylene (HCFO-1121), 1-chloro-2-fluoroethylene (HCFO-1131), 2-chloro -3,3,3-Trifluoropropene (HCFO-1233xf), 1-Chloro-2,3,3-trifluoro-1-propene (HCFO-1233yd) and 1-Chloro-3,3,3-tetrafluoro Propene (HCFO-1233zd) may be mentioned.

As other HCFOs, HCFO-1233zd is preferable from the viewpoint of having high critical temperature and being excellent in durability and coefficient of performance. One of other HCFOs may be used alone, or two or more thereof may be used in combination.

(Other optional ingredients)
The working medium used for the thermal cycle system of the present embodiment may contain carbon dioxide, hydrocarbons, chlorofluoroolefin (CFO), etc., in addition to the above components. As another optional component, a component which has less influence on the ozone layer and has less influence on global warming is preferable.

As a hydrocarbon, propane, propylene, cyclopropane, butane, isobutane, pentane, isopentane and the like can be mentioned. The hydrocarbon may be used alone or in combination of two or more. The inclusion of the hydrocarbon improves the solubility of the mineral lubricating oil in the working medium.
When the working medium contains a hydrocarbon, the hydrocarbon content is preferably 10% by mass or less based on 100% by mass of the working medium from the viewpoint of combustibility, more preferably 5% by mass or less .

Examples of CFO include chlorofluoropropene and chlorofluoroethylene. As CFO, 1,1-dichloro-2,3,3,3-tetrafluoropropene (CFO-1214ya), 1 as a CFO, because the flammability of the working medium can be easily suppressed without significantly reducing the cycle performance of the working medium. Preferred is 3, 3-dichloro-1,2,3,3-tetrafluoropropene (CFO-1214yb) or 1,2-dichloro-1,2-difluoroethylene (CFO-1112). The CFO may be used alone or in combination of two or more.

When the working medium contains the optional components as described above, the content of each optional component is 50% by mass or less, preferably 30% by mass or less, and further 20% by mass or less based on 100% by mass of the working medium. Preferably, 10% by mass or less is particularly preferable. When a plurality of optional components are contained, the total content of the optional components in the working medium is 50% by mass or less, preferably 30% by mass or less, and more preferably 20% by mass or less, with respect to 100% by mass of the working medium. 10 mass% or less is especially preferable.

<Composition for Thermal Cycle System>
The working medium of the present embodiment can be used as a composition for a heat cycle system of the present embodiment including the application to a heat cycle system. The composition for a thermal cycle system of the present embodiment usually contains a lubricating oil in addition to the working medium of the present embodiment described above. Further, the composition for a heat cycle system of the present embodiment may contain known additives such as a stabilizer and a leak detection substance. These lubricating oils and additives can also be used in combination.

(Lubricant)
As the lubricating oil, a known lubricating oil used in the working medium composition can be adopted without particular limitation, together with the working medium conventionally composed of halogenated hydrocarbons. Specific examples of the lubricating oil include oxygen-containing synthetic oils (ester-based lubricating oils, ether-based lubricating oils and the like), fluorine-based lubricating oils, mineral-based lubricating oils, hydrocarbon-based synthetic oils and the like.

As ester-based lubricating oils, dibasic acid ester oils, polyol ester oils, complex ester oils, polyol carbonate oils and the like can be mentioned.

Examples of ether-based lubricating oils include polyvinyl ether oils and polyoxyalkylene oils such as polyglycol oils.

Examples of fluorine-based lubricating oils include compounds in which hydrogen atoms of synthetic oils (mineral oil, poly α-olefin, alkylbenzene, alkylnaphthalene, etc. described later) are substituted with fluorine atoms, perfluoropolyether oils, fluorinated silicone oils, etc. Be

As a mineral-based lubricating oil, a lubricating oil fraction obtained by atmospheric distillation or vacuum distillation of crude oil is subjected to purification treatment (solvent removal, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrogenation The paraffinic mineral oil, the naphthenic mineral oil, etc. which refine | purified and refine | purified by appropriate | suitably refine | purifying, clay treatment etc. are mentioned.

Examples of hydrocarbon synthetic oils include poly α-olefins, alkylbenzenes and alkylnaphthalenes.

The lubricating oils may be used alone or in combination of two or more.
The lubricating oil is preferably at least one selected from polyol ester oils, polyvinyl ether oils and polyglycol oils from the viewpoint of compatibility with the working medium.

The addition amount of the lubricating oil may be in a range that does not significantly reduce the effects of the present invention, and is preferably 10 to 100 parts by mass, and more preferably 20 to 50 parts by mass with respect to 100 parts by mass of the working medium.

(Stabilizer)
Stabilizers are components that improve the stability of the working medium against heat and oxidation. As the stabilizer, there are no particular limitations on known stabilizers conventionally used in thermal cycle systems, such as oxidation resistance improvers, heat resistance improvers, metal deactivators, etc., together with the working medium conventionally made of halogenated hydrocarbons. It can be adopted.

As the oxidation resistance improver and heat resistance improver, N, N'-diphenyl phenylene diamine, p-octyl diphenylamine, p, p'-dioctyl diphenylamine, N-phenyl-1-naphthylamine, N-phenyl-2-naphthylamine N- (p-dodecyl) phenyl-2-naphthylamine, di-1-naphthylamine, di-2-naphthylamine, N-alkylphenothiazine, 6- (t-butyl) phenol, 2,6-di- (t-butyl) And the like) phenol, 4-methyl-2,6-di- (t-butyl) phenol, 4,4'-methylenebis (2,6-di-t-butylphenol) and the like. As the oxidation resistance improver and the heat resistance improver, one type may be used alone, or two or more types may be used in combination.

Examples of metal deactivators include imidazole, benzimidazole, 2-mercaptobenzthiazole, 2,5-dimethylcaptothiadiazole, salicylidine-propylenediamine, pyrazole, benzotriazole, toltriazole, 2-methylbenzamidazole, 3,5- Dimethylpyrazole, methylenebis-benzotriazole, organic acids or their esters, primary, secondary or tertiary aliphatic amines, amine salts of organic acids or inorganic acids, heterocyclic nitrogen-containing compounds, alkyl acid phosphates Amine salts or derivatives thereof.

The addition amount of the stabilizer may be within a range not significantly reducing the effects of the present invention, and is preferably 5 parts by mass or less, and more preferably 1 part by mass or less with respect to 100 parts by mass of the working medium.

(Leakage detection substance)
As a leak detection substance, an ultraviolet fluorescent dye, an odor gas, an odor masking agent and the like can be mentioned.
Ultraviolet fluorescent dyes are described in U.S. Pat. No. 4,249,412, JP-A-10-502737, JP-A-2007-511645, JP-A-2008-500437, and JP-A-2008-531836. Known ultraviolet fluorescent dyes used in thermal cycle systems, as well as working media conventionally comprising halogenated hydrocarbons, such as those described in U.S. Pat.

As odor masking agents, known perfumes used in heat cycle systems together with working media conventionally comprising halogenated hydrocarbons such as those described in JP-A-2008-500437 and JP-A-2008-531836 are known. It can be mentioned.

When a leak detection substance is used, a solubilizer may be used to improve the solubility of the leak detection substance in the working medium.

Examples of solubilizers include those described in JP-A-2007-511645, JP-A-2008-500437, and JP-A-2008-531836.

The addition amount of the leak detection substance may be within the range not significantly reducing the effects of the present invention, preferably 2 parts by mass or less and more preferably 0.5 parts by mass or less with respect to 100 parts by mass of the working medium.

<Thermal cycle system>
The thermal cycle system of the present embodiment is obtained by applying a composition for a thermal cycle system including the above-mentioned working medium to an apparatus and device for thermal cycle. The thermal cycle system includes a thermal cycle system including a heat exchanger such as a compressor, a condenser and an evaporator.

The heat cycle system of the present embodiment may be a heat pump system that utilizes the heat obtained by the condenser, or may be a refrigeration cycle system that uses the cold heat obtained by the evaporator. The thermal cycle system of the present embodiment may be a flooded evaporator type or a direct expansion type. In the thermal cycle system of the present embodiment, water or air is preferable as the substance other than the working medium which is heat-exchanged with the working medium.

Specific examples of the heat cycle system of the present embodiment include refrigeration / refrigeration equipment, air conditioning equipment, power generation system, heat transport device, secondary cooler, and the like. Among them, the thermal cycle system of the present embodiment is preferably used as an air conditioner that is often installed outdoors, since it can stably exhibit cycle performance even in a higher temperature operating environment. Moreover, it is also preferable that the thermal cycle system of this embodiment is used as a freezing / refrigerating apparatus.

The power generation system is preferably a Rankine cycle system power generation system. As a power generation system, specifically, the working medium is heated by geothermal energy, solar heat, middle to high temperature range waste heat at about 50 to 200 ° C. in an evaporator, and the working medium that has become high-temperature high-pressure steam is expanded An example is a system in which adiabatic expansion is performed in a machine, and a work generated by the adiabatic expansion drives a generator to generate electric power.

In addition, the heat cycle system of the present embodiment may be a heat transport device. As a heat transport device, a latent heat transport device is preferable. Examples of the latent heat transport device include a heat pipe that performs latent heat transport utilizing phenomena such as evaporation, boiling, and condensation of a working medium enclosed in the device, and a two-phase closed thermosiphon device. The heat pipe is applied to a relatively small cooling device such as a cooling device for a semiconductor element or a heat generating portion of an electronic device. Since the two-phase closed thermosyphon does not require a wig and has a simple structure, it is widely used for gas-to-gas heat exchangers, snow melting on roads, prevention of freezing, and the like.

Specific examples of the refrigeration / refrigeration equipment include showcases (built-in showcases, separately mounted showcases, etc.), commercial freezers / refrigerators, vending machines, ice makers, and the like.

As air conditioners, specifically, room air conditioners, package air conditioners (package air conditioners for buildings, package air conditioners for buildings, equipment package air conditioners, etc.), heat source equipment chilling units, gas engine heat pumps, train air conditioners, car air conditioners Etc.

The heat source equipment chilling unit includes, for example, a volumetric compression type refrigerator and a centrifugal type refrigerator. However, since the centrifugal type refrigerator to be described next has a large amount of the working medium, the effect of the present embodiment is more remarkable. Preferably obtained.

Here, the centrifugal refrigerator is a refrigerator using a centrifugal compressor. A centrifugal refrigerator is a type of vapor compression refrigerator, and is generally referred to as a turbo refrigerator. A centrifugal compressor includes an impeller and performs compression by discharging a working medium to the outer peripheral portion by the rotating impeller. Centrifugal refrigerators are used in office buildings, district heating and cooling, heating and cooling in hospitals, semiconductor factories, cold water production plants in the petrochemical industry, and the like.

The centrifugal refrigerator may be either a low pressure type or a high pressure type, but is preferably a low pressure type centrifugal refrigerator. The low-pressure type is a working medium that is not subject to the High Pressure Gas Safety Act such as CFC-11, HCFC-123, HFC-245fa, that is, "The pressure is 0.2 MPa or more at ordinary temperature. A centrifugal refrigerator that uses a working medium that does not correspond to a liquefied gas that is currently at a pressure of 0.2 MPa or more, or at a temperature of 35 ° C. or less when the pressure is 0.2 MPa or more .

In addition, in order to avoid generation | occurrence | production of the malfunction by mixing of water, and mixing of noncondensable gas, such as oxygen, it is preferable to provide the means to suppress these mixing in the case of operation | movement of a thermal cycle system.

The inclusion of moisture in the thermal cycling system can cause problems, especially when used at low temperatures. For example, problems such as freezing in a capillary tube, hydrolysis of a working medium or refrigeration oil, material deterioration due to an acid component generated in a cycle, generation of contamination, etc. occur. In particular, when the refrigerator oil is a polyalkylene glycol, polyol ester or the like, the hygroscopicity is extremely high, and a hydrolysis reaction is likely to occur, and the characteristics as a refrigerator oil are degraded, and the long-term reliability of the compressor is impaired. It becomes a cause. Therefore, in order to suppress the hydrolysis of refrigeration oil, it is necessary to control the moisture concentration in the thermal cycle system.

As a method of controlling the water concentration in the heat cycle system, a method using a water removing means such as a desiccant (silica gel, activated alumina, zeolite, etc.) can be mentioned. It is preferable in terms of dewatering efficiency that the desiccant be brought into contact with the liquid thermal cycle system composition. For example, it is preferable to place a desiccant at the outlet of the condenser or at the inlet of the evaporator to contact the composition for the thermal cycle system.

As the desiccant, a zeolitic desiccant is preferable from the viewpoint of the chemical reactivity between the desiccant and the composition for a heat cycle system and the moisture absorption capacity of the desiccant.

When a refrigeration oil having a high moisture absorption amount is used as a zeolite-based desiccant compared to a conventional mineral-based refrigeration oil, the compound represented by the following formula (C) is the main component from the viewpoint of excellent moisture absorption capacity. Zeolite based desiccants are preferred.

M _{2 / n} O · Al ₂ O ₃ · x SiO ₂ · y H ₂ O (C)

However, M is an element of Group 1 such as Na and K or an element of Group 2 such as Ca, n is a valence of M, and x and y are values determined by the crystal structure. The pore size can be adjusted by changing M.

The pore size and the breaking strength are important in the selection of the desiccant. When a desiccant having a pore size larger than the molecular diameter of various components (hereinafter, "working media etc.") such as working media contained in the composition for thermal cycle system is used, the working media etc. is adsorbed in the desiccant As a result, a chemical reaction between the working medium and the like and the desiccant occurs, which causes undesirable phenomena such as generation of noncondensable gas, reduction in strength of the desiccant, and reduction in adsorption capacity.

Therefore, as the desiccant, it is preferable to use a zeolite-based desiccant with a small pore size. In particular, a sodium-potassium A-type synthetic zeolite having a pore size of 3.5 angstroms or less is preferable. By applying the sodium-potassium A-type synthetic zeolite having a pore diameter smaller than the molecular diameter of the working medium or the like, it is possible to selectively adsorb and remove only the water in the heat cycle system without adsorbing the working medium or the like. In other words, since adsorption to the desiccant such as the working medium does not easily occur, thermal decomposition hardly occurs, and as a result, it is possible to suppress the deterioration of the materials constituting the thermal cycle system and the generation of contaminants.

If the size of the zeolitic desiccant is too small, it will cause clogging in the valve and piping details of the thermal cycle system, and if it is too large, the drying ability will decrease, so a particle size of about 0.5 to 5 mm is preferable as a typical particle size. . The shape is preferably granular or cylindrical.

The zeolitic desiccant can be made into an arbitrary shape by solidifying powdered zeolite with a binder (bentonite or the like). Other desiccants (silica gel, activated alumina, etc.) may be used in combination as long as the zeolite-based desiccant is mainly used.

Furthermore, if the non-condensable gas is mixed in the thermal cycle system, it has an adverse effect of poor heat transfer in the condenser and the evaporator and an increase in operating pressure, so it is necessary to suppress the mixing as much as possible. In particular, oxygen, which is one of the non-condensable gases, reacts with the working medium and refrigerator oil to promote decomposition.

The noncondensable gas concentration is preferably 1.5% by volume or less by volume ratio to the working medium in the gas phase portion of the working medium, and particularly preferably 0.5% by volume or less.

As mentioned above, although the thermal cycle system of this embodiment was demonstrated, the thermal cycle system of this embodiment is not limited above. These embodiments can be modified or changed without departing from the spirit and scope of the present invention.

In the heat cycle system of the present embodiment, a predetermined composition for a heat cycle system including the working medium of the present embodiment is used. Therefore, the thermal cycle system using the composition for a thermal cycle system containing this working medium has good cycle performance as described above, and the effect on global warming is suppressed by sufficiently low ODP and GWP. It is an excellent material that exhibits the characteristics of a highly safe working medium with reduced flammability. In particular, by suppressing the flammability of the working medium, even if any trouble occurs in the thermal cycle system, it is possible to avoid dangers such as fire and explosion.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited to the following examples.

[Example 1-1 to 1-9]
A working medium was prepared by mixing HCFO-1224yd (Z) and HFO-1234ze (E) in the proportions shown in Table 2, and the temperature gradient and refrigeration cycle performance (refrigerating capacity Q and coefficient of performance COP) were measured by the following method did.

<Measurement of temperature gradient, refrigeration cycle performance>
The measurement of temperature gradient and refrigeration cycle performance (refrigeration capacity and coefficient of performance) applies the working medium to the refrigeration cycle system 10 shown in FIG. 1 and adiabatic compression by the compressor 11 in the thermal cycle shown in FIG. In the BC process, isobaric cooling by the condenser 12, isenthalpic expansion by the expansion valve 13 in the CD process, and isobaric heating by the evaporator 14 in the DA process.

Measurement conditions are the evaporation temperature of working medium in evaporator 14 (average temperature of evaporation start temperature and evaporation completion temperature) 5 ° C., condensation completion temperature of working medium in condenser 12 (average temperature of condensation start temperature and condensation completion temperature) C., the degree of subcooling (SC) of the working medium in the condenser 12 as 5.degree. C., and the degree of superheat (SH) of the working medium in the evaporator 14 as 0.degree. In addition, the compressor efficiency was 0.8, and there was no pressure loss in the piping and the heat exchanger.

The refrigeration capacity and coefficient of performance are the enthalpy of each state of the working medium A (evaporation, high temperature and low pressure), B (compression, high temperature and high pressure after compression), C (condensed, low temperature and high pressure after condensation), and D (low temperature, low pressure after expansion). It calculated | required from said Formula (A), (B) using h.

The thermodynamic properties required to calculate the refrigeration cycle performance were calculated based on the generalized equation of state (Soave-Redlich-Kwong equation) based on the corresponding state principle, and thermodynamic relations. When characteristic values were not available, calculation was performed using the estimation method based on the group contribution method.

The refrigerating capacity and the coefficient of performance were determined as relative ratios when the refrigerating capacity and coefficient of performance of HCFC-1224 yd (Z) measured in the same manner as described above were respectively 1.00. The temperature gradient was determined as the difference between T ₁ and T ₂ in FIG. Also, the GWP of the working fluid was determined based on the GWP of each compound shown in Table 1 as a weighted average by composition mass. That is, the GWP of the working medium was determined by dividing the sum of the product of the mass% of each compound constituting the working medium and the GWP by 100. The working media of Examples 1-1 to 1-9 all have an ODP of 0.

[Examples 2-1 to 2-8]
A working medium was prepared by mixing HCFO-1224yd (Z) and HFO-1234yf in the proportions shown in Table 3, and temperature gradient and refrigeration cycle performance (refrigerating capacity Q and coefficient of performance COP) were prepared in the same manner as in Example 1 above. It was measured. The working media of Examples 2-1 to 2-8 all have an ODP of 0.

[Example 3-1 to 3-15]
A working medium was prepared by mixing HCFO-1224yd (Z), HFO-1234ze (E) and HFO-1234yf in the proportions shown in Table 4, and in the same manner as Example 1 above, the temperature gradient and the refrigeration cycle performance (refrigerating capacity Q and coefficient of performance COP were measured. The working media of Examples 3-1 to 3-15 all have an ODP of 0.

[Examples 4-1 to 4-9]
A working medium was prepared by mixing HCFO-1224yd (Z) and HFO-1234ze (Z) in the proportions shown in Table 5, and in the same manner as in Example 1 above, temperature gradient and refrigeration cycle performance (refrigerant capacity Q and coefficient of performance) COP) was measured. The working media of Examples 4-1 to 4-9 all have an ODP of 0.

As can be seen from Tables 2 to 5, all working media of Examples 1-1 to 1-9, Examples 2-1 to 2-8, and Examples 3-1 to 3-15, which are Examples, are HCFO-1224yd. (Z) Superior in refrigeration capacity and coefficient of performance compared to Examples 4-1 to 4-9 using a single working medium or a working medium in which HCFO-1224yd (Z) and HFO-1234ze (Z) are mixed. It is a working medium for thermal cycling that is almost equivalent and has sufficient cycle performance, and the effects on global warming are sufficiently suppressed by sufficiently low ODP and GWP.

<Flammability test>
Next, a working fluid for thermal cycle comprising the mixture obtained in Examples 1-6 to 1-9 and Examples 2-6 to 2-8, and further, 10% by mass of HCFO-1224yd (Z), HFO-1234ze Thermal cycle working medium (Example 1-10) consisting of a mixture of 90% by weight of (E), thermal cycle working medium consisting of a mixture of 20% by weight of HCFO-1224yd (Z) and 80% by weight of HFO-1234yf With regard to (Examples 2-9), each working medium was mixed with air at a ratio of every 10% to 90% by mass with respect to air to evaluate the flammability when it reached an equilibrium state.

The flammability evaluation was performed as follows using the equipment specified in ASTM E-681. After evacuating the inside of a 12-liter flask installed in a thermostat controlled at 58.0-59.0 ° C, each working medium mixed with air at the above ratio was sealed up to atmospheric pressure . Thereafter, in the gas phase near the center in the flask, discharge ignition was performed at 15 kV and 30 mA for 0.4 seconds, and the spread of the flame was visually confirmed. It was judged to be combustible when the angle of the flame spread upward was 90 degrees or more, and not combustible when it was less than 90 degrees. The results are shown in Tables 6 and 7.

The compounds constituting the working medium used here are summarized in Tables 2-3. The working media shown in Tables 2 to 3 are working media in the non-combustible range, and are also shown together with the evaluation of the refrigeration cycle performance of the working media and the evaluation of the global warming potential (GWP).

From the above results, it is found that the thermal cycle working medium consisting of a mixture of HCFO-1224yd (Z) and HFO-1234ze (E) has sufficient combustibility if 20% by mass or more of HCFO-1224yd (Z) is contained. It has been found that it is possible to make it a highly safe working medium.

In addition, the thermal cycle working medium consisting of a mixture of HCFO-1224yd (Z) and HFO-1234yf is sufficiently reduced in flammability as long as HCFO-1224yd (Z) is contained in an amount of 30% by mass or more. It turned out that it can be considered as highly safe.

The working medium of the present embodiment, a composition for a thermal cycle system including the same, and a thermal cycle system using the composition can be used as a refrigerating / refrigerating device (built-in showcase, separate showcase, freezer / refrigerator for business use, Vending machines, ice makers, etc., air conditioners (room air conditioners, package air conditioners for stores, package air conditioners for buildings, equipment package air conditioners, heat source equipment chilling units, gas engine heat pumps, air conditioners for trains, air conditioners for automobiles, etc.) It can be used for power generation systems (such as waste heat recovery power generation), heat transport devices (such as heat pipes), and secondary coolers.

DESCRIPTION OF SYMBOLS 10 ... Refrigeration cycle system, 11 ... Compressor, 12 ... Condenser, 13 ... Expansion valve, 14 ... Evaporator, 15, 16 ... Pump.

Claims

A working medium for thermal cycling comprising 1-chloro-2,3,3,3-tetrafluoropropene and (E) -1,3,3,3-tetrafluoropropene,
The total content of the 1-chloro-2,3,3,3-tetrafluoropropene and the (E) -1,3,3,3-tetrafluoropropene contained in the thermal cycle working medium is 50 % Or more, and the ratio of 1-chloro-2,3,3,3-tetrafluoropropene: (E) -1,3,3,3-tetrafluoropropene is on a mass basis, 20. A working medium for thermal cycling characterized in that it is 20: 80 to 99: 1.
A working medium for thermal cycling, comprising 1-chloro-2,3,3,3-tetrafluoropropene and 2,3,3,3-tetrafluoropropene,
The total content of the 1-chloro-2,3,3,3-tetrafluoropropene and the 2,3,3,3-tetrafluoropropene contained in the thermal cycle working medium is 50% by mass or more And the ratio of 1-chloro-2,3,3,3-tetrafluoropropene represented by 2,3,3,3-tetrafluoropropene is from 30:70 to 99: 1 on a mass basis. A working fluid for thermal cycling, characterized in that
The 1-chloro-2,3,3,3-tetrafluoropropene is (E) -1-chloro-2,3,3,3-tetrafluoropropene: (Z) -1-chloro-2,3, The working fluid for thermal cycling according to claim 1 or 2, wherein the ratio represented by 3, 3-tetrafluoropropene is 50: 50 to 0.01: 99.99 on a mass basis.
A composition for a thermal cycle system comprising the thermal cycle working medium according to any one of claims 1 to 3.
The composition for a heat cycle system according to claim 4, comprising a lubricating oil.
The composition for a heat cycle system according to claim 4 or 5, further comprising a stabilizer that suppresses the deterioration of the heat cycle working medium.
A thermal cycle system using the composition for a thermal cycle system according to any one of claims 4 to 6.
The heat cycle system according to claim 7, wherein the heat cycle system is a refrigeration / refrigerator, an air conditioner, a power generation system, a heat transport device or a secondary cooler.
The heat cycle system according to claim 7 or 8, wherein the heat cycle system is a centrifugal refrigerator.
The thermal cycle system according to any one of claims 7 to 9, wherein the thermal cycle system is a low pressure centrifugal refrigerator.