CN112877035B

CN112877035B - Refrigerant mixture and air conditioning system

Info

Publication number: CN112877035B
Application number: CN202011578069.4A
Authority: CN
Inventors: 曾婧; 江世恒; 张宗云
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2020-12-28
Filing date: 2020-12-28
Publication date: 2022-04-08
Anticipated expiration: 2040-12-28
Also published as: CN112877035A

Abstract

The present disclosure provides a refrigerant blend and an air conditioning system, the refrigerant blend comprising a mixed refrigerant comprising a first component, a second component, and a third component, wherein: the first component is difluoromethane, the second component is monofluoroethane, and the third component is trans-1, 2-difluoroethylene. The mixed refrigerant provided by the disclosure has the obvious effects of saving energy and reducing emission, wherein GWP is less than or equal to 500. In the aspect of combustibility, the novel refrigerant A2 is slightly combustible, does not have the filling amount limitation, and solves the problem that the novel refrigerant A2 cannot be used on a household air conditioner with 2P or more of cold. The cycling capability, the energy efficiency and the temperature range of the usable environment are equivalent to those of R22, R290 or R410A, and the cycling performance is better under high-temperature environments such as the middle east. Compared with the refrigerant filling amount in the R22 system, the filling amount is reduced by more than 28 percent, and the slip temperature is lower (within 3 ℃).

Description

Refrigerant mixture and air conditioning system

Technical Field

The disclosure belongs to the technical field of refrigeration, and particularly relates to a refrigerant mixture and an air conditioning system.

Background

Several laws have been published internationally since 2014 to limit the use of high GWP refrigerants. For example, the European Union's F-GAS Act proposes that 2015-. Historical limited control greenhouse gas Hydrofluorocarbon (HFCs) amendments, Bas California amendments, were achieved in 10 months in 2016, and the current household air conditioners used R22(GWP 1760), R32(GWP 677), and R410A (GWP 2100) in controlled ranges, so the research on refrigerants with low GWP values must be accelerated.

The international research on the replacement of the novel low GWP value refrigerant mainly comprises novel HFCs (high frequency hydrocarbons) substitutes, Hydrofluoroolefins (HFOs) substitutes and hydrocarbon refrigerant natural working media. R161 is a novel HFCs substitute with great potential, ODP is 0, GWP is 4, thermophysical property is good, theoretical and actual measurement performance is equivalent to R32, but the combustion grade is 3, and unit volume refrigerating capacity is about 9% lower than R22, so that the refrigerant needs to be mixed with other refrigerants to reduce flammability and improve unit volume refrigerating capacity.

Reference CN107532074A provides a refrigerant composition comprising a composition (I) of one or more components (A) selected from alkanes, halogenated alkanes and alkenes and one or more components (B) consisting of halogenated alkenes, or a composition (II) comprising two or more components (B) comprising a halogenated olefin (wherein A is selected from the group consisting of R32, R161, ethane, etc., and B is selected from the group consisting of tetrafluoroethylene, R1123, cis-1, 2-difluoroethylene R1132(Z), trans-1, 2-difluoroethylene R1132(E), and 1, 1-difluoroethylene R1132a) (but excluding the above-mentioned composition (I) although combinations of R32, R161, and R1132(E) are disclosed, however, the components are limited only according to the condition that the combustion inhibition effect reaches more than 10%, the GWP value, the mixed energy efficiency, the slip temperature and the like are not considered, and the wide range of the components has low applicability in household refrigeration systems.

The existing application refrigerant is mainly disclosed by considering an ODP value, a GWP value, a flame retardant effect and the like, and the problems of capability, energy efficiency, temperature slippage, high-temperature environmental performance and the like after the mixed refrigerant is mixed are less considered. After the refrigerant is replaced in the system, the discharge capacity of the original compressor cannot meet the requirement of the nominal refrigerating capacity, the original two devices cannot meet the requirement of the nominal energy efficiency grade, the after-sales charging system has the energy efficiency fluctuation caused by the large temperature slippage, and the condensation heat exchange effect is poor in the high-temperature environment with the lower critical temperature.

Because technical problems that refrigerants in the prior art cannot simultaneously guarantee low GWP value and low flammability of the refrigerants and the like, the refrigerant mixture and the air-conditioning system are researched and designed by the disclosure.

BRIEF SUMMARY OF THE PRESENT DISCLOSURE

Therefore, the technical problem to be solved by the present disclosure is to overcome the defect of the prior art that the refrigerant cannot simultaneously ensure low GWP value and low flammability of the refrigerant, thereby providing a refrigerant mixture and an air conditioning system.

The present disclosure provides a refrigerant mixture, wherein:

comprising a mixed refrigerant comprising a first component, a second component, and a third component, wherein: the first component is difluoromethane, the second component is monofluoroethane, and the third component is trans-1, 2-difluoroethylene.

In some embodiments, the mass ratio of difluoromethane to the mixed refrigerant is (0%, 73%), the mass ratio of monofluoroethane to the mixed refrigerant is (0%, 74%), and the mass ratio of trans 1, 2-difluoroethylene to the mixed refrigerant is (0%, 40%), in mass%.

In some embodiments, the mass ratio of difluoromethane to the mixed refrigerant is [ 10%, 22% ], the mass ratio of monofluoroethane to the mixed refrigerant is [ 50%, 61% ], and the mass ratio of trans 1, 2-difluoroethylene to the mixed refrigerant is [ 17%, 29% ].

In some embodiments, the difluoromethane makes up the mixed refrigerant at a mass ratio of [ 30%, 44% ], the monofluoroethane makes up the mixed refrigerant at a mass ratio of [ 24%, 40% ], and the trans 1, 2-difluoroethylene makes up the mixed refrigerant at a mass ratio of [ 20%, 32% ].

In some embodiments, the mass ratio of difluoromethane to the mixed refrigerant is [ 63%, 73% ], the mass ratio of monofluoroethane to the mixed refrigerant is [ 5%, 15% ], and the mass ratio of trans 1, 2-difluoroethylene to the mixed refrigerant is [ 16%, 30% ].

In some embodiments, the refrigerant mixture further comprises a stabilizer, and the mass ratio of the stabilizer to the refrigerant mixture is 0% to 1-2% to 1.

In some embodiments, the stabilizer comprises two components, wherein the first component comprises one, two or more combinations of ether compounds and the second component comprises one, two or more combinations of thiols, calcium sulfonates, aryl sulfides, tricresyl phosphate.

The present disclosure also provides an air conditioning system comprising the refrigerant blend of any of the preceding.

In some embodiments, the air conditioning system is a single or dual stage compression refrigeration cycle.

In some embodiments, the air conditioning system is a domestic air conditioning system.

The refrigerant mixture and the air conditioning system provided by the present disclosure have the following beneficial effects:

the environment-friendly mixed refrigerant (R32/R161/R1132(E)) can be used as a substitute refrigerant of R22, R290 or R410A and applied to household air-conditioning refrigeration equipment, and the mixed refrigerant provided by the disclosure has obvious energy-saving and emission-reduction effects with GWP less than or equal to 500. In the aspect of combustibility, the novel refrigerant A2 is slightly combustible, does not have the filling amount limitation, and solves the problem that the novel refrigerant A2 cannot be used on a household air conditioner with 2P or more of cold. The cycling capability, the energy efficiency and the temperature range of the usable environment are equivalent to those of R22, R290 or R410A, and the cycling performance is better under high-temperature environments such as the middle east. Compared with the refrigerant filling amount in the R22 system, the filling amount is reduced by more than 28 percent, and the slip temperature is lower (within 3 ℃).

Drawings

FIG. 1 is a graph of glide temperature profiles of refrigerant blends of the present disclosure;

FIG. 2 is a theoretical cycle calculated pressure-enthalpy diagram for the refrigerant blends of the present disclosure;

FIG. 3 is a system diagram of a single stage compression refrigeration cycle of the refrigerant mixture of the present disclosure;

fig. 4 is a system diagram of a dual-stage compression refrigeration cycle of the refrigerant mixture of the present disclosure.

Detailed Description

As shown in fig. 1-4, the present disclosure provides a refrigerant mixture, wherein:

comprising a mixed refrigerant comprising a first component, a second component, and a third component, wherein: the first component is difluoromethane (R32), the second component is monofluoroethane (R161), and the third component is trans 1, 2-difluoroethylene (R1132 (E)).

The present disclosure can be applied to household air-conditioning refrigeration equipment as a substitute refrigerant of R22, R290 or R410A by providing an environment-friendly mixed refrigerant (R32/R161/R1132 (E)). The mixed refrigerant provided by the disclosure has obvious energy-saving and emission-reducing effects, wherein GWP is less than or equal to 500. In terms of combustibility, the novel refrigerant A2 is slightly flammable, has no filling amount limitation, and cannot be used on household air conditioners with 2P or more of refrigeration capacity. The cycling capability, the energy efficiency and the temperature range of the usable environment are equivalent to those of R22, R290 or R410A, and the cycling performance is better under high-temperature environments such as the middle east. Compared with the refrigerant filling amount in the R22 system, the filling amount is reduced by more than 28 percent, and the slip temperature is lower (within 3 ℃).

The present disclosure provides a novel mixed refrigerant, which has low GWP value of the environment-friendly refrigerant, small temperature slippage, good cycle performance, wide temperature range of usable environment, especially suitable for high temperature environment, a2 micro-flammable property, and significantly reduced filling amount, and can be used as a substitute for R290, R22 or R410A.

The present disclosure can effectively solve the following technical problems:

1. the GWP value of the refrigerant is reduced, the requirement of international relevant laws on carbon emission reduction is met, and the research and development trend of low GWP value of a novel substitute refrigerant is met.

2. The flammability of the refrigerant is reduced, the safety level of the mixed refrigerant can reach A2 micro flammability, and the problem that the refrigerant with 3 combustion levels such as R290, R161 and the like has perfusion volume limitation and cannot be used on a household air conditioner with 2P or more cold quantity is avoided.

3. The cycle performance is improved, the mixed refrigerant can realize the direct replacement of the refrigerant of the original system, the discharge capacity of the compressor is adjusted according to the requirement, the configuration of two devices is not required to be increased or the motor is not required to be optimized, and the filling amount is reduced. The environment temperature range is wide, the device is particularly suitable for high-temperature environments such as the middle east, and the energy efficiency is high in the high-temperature environment.

4. The mixed refrigerant has small sliding temperature (within 3 ℃), and the possibility of component migration caused by the sliding temperature is reduced, so that the problem of capacity and energy efficiency fluctuation caused by after-sale filling is avoided.

The invention provides an environment-friendly refrigerant with low GWP value, which is prepared by mixing difluoromethane (R32), monofluoroethane (R161) and trans-1, 2-difluoroethylene (R1132(E)), wherein the basic parameters of each component are shown in Table 1. R161 is a novel HFCs substitute with great potential, ODP is 0, GWP is 4, thermophysical property is good, theoretical and actual measurement performance is equivalent to R32, but the combustion grade is 3, and unit volume refrigerating capacity is about 9% lower than R22, so that the refrigerant needs to be mixed with other refrigerants to reduce flammability and improve unit volume refrigerating capacity. R1132(E) is a substitute of Hydrofluoroolefins (HFOs), contains halogen atoms with a high proportion, has a flame-retardant effect, has high flame-retardant reactivity with carbon-carbon double bonds, has good GWP 1 environmental protection performance, and has a unit volume refrigerating capacity which is about 10 percent lower than that of R22. R32 has excellent cycle performance and higher refrigerating capacity per unit volume, but has higher GWP value. The other three have close standard boiling points, and the temperature slippage is small after mixing. After the three components are combined into a composition, the respective defects can be improved, the comprehensive performance of the composition can be improved, the GWP of the refrigerant is effectively controlled, the combustion safety grade is 2, the filling amount and the sliding temperature are reduced, and the refrigerant can replace R22, R290 or R410A in household air conditioners.

TABLE 1 basic parameters of the component materials in the refrigerant compositions

In the environment-friendly refrigerant with low GWP value, the mass fraction of difluoromethane is (0%, 73%), the mass fraction of monofluoroethane is (0%, 74%), and the mass fraction of trans-1, 2-difluoroethylene is (0%, 40%), at the moment, the GWP of the mixed refrigerant is less than 500, the slipping temperature is less than 3 ℃, the combustion safety level is 2 types of micro-combustibility, the refrigerating capacity per unit mass is more than 140% of R22, and the filling capacity is reduced by more than 28%, so that the refrigerant can be used as a substitute for R290, R22 or R410A to be applied to a household air conditioning system.

The refrigerant component ratios are determined mainly from the following 4 points of view, and the basic parameters of the refrigerant composition are shown in table 2.

(1) GWP value: the GWP of R32 in the component (A) is the largest, and the influence on the GWP of the mixture is the most obvious. The mass proportion of the mixture component R32 is less than 22 percent, and the GWP value of the mixture is less than 150; the mass proportion of the mixture component R32 is less than 44 percent, and the GWP value of the mixture is less than 300; the mass proportion of the mixture component R32 is less than 73 percent, and the GWP value of the mixture is less than 500. The mass ratio of R32 is reduced, the requirement of carbon emission reduction can be met, and the environment-friendly performance is good.

(2) Combustible grade aspect: the mixture component R161 has the highest flammability, the heat of combustion is 22MJ/kg, and the lower limit of combustion is 3.8%. According to the classification of the standard ISO 817(2014) on combustion grades, the mass proportion of the R161 is limited to be less than 74 percent, the combustion heat is less than 19MJ/kg, the lower combustion limit is greater than 3.5 percent, and the refrigerant belongs to class 2 micro-combustible refrigerants. The product is superior to R290 of type 3, is not limited by the filling amount when being applied to a household air conditioner, and can be suitable for units above 2 p.

(3) Slip temperature aspect: the boiling points of 3 components are not greatly different, and the change of the mixed refrigerant slip temperature along with the mass ratio of R32 under the pressure of 0.1MPa is shown in figure 1, and the slip temperature is less than 3 ℃ in the whole view. When the mass ratio of R32 is 0.25-0.5, the slip temperature is higher, and in the interval, the mass ratio of R161 and R1132(E) needs to be refined and adjusted to further reduce the slip temperature. Wherein the slippage temperature is the difference between the dew point temperature and the bubble point temperature under the pressure, the slippage temperature is preferably controlled to be less than 2 ℃ by adjusting the proportion of each component, and the refrigerant can be regarded as a near azeotropic refrigerant.

(4) Thermal parameters and cycle performance: the unit volume refrigerating capacity of the component R32 is larger, the working pressure is larger, the critical temperature is lower, and the high-temperature working condition has more obvious attenuation compared with the COP (coefficient of performance) R22; the unit volume refrigerating capacity of the components R161 and R1132(E) is small, the working pressure is small, the critical temperature is high, and the high-temperature working condition is basically not attenuated compared with the COP (coefficient of performance) R22.

TABLE 2 basic parameters of refrigerant compositions

Therefore, the refrigerant components can adopt different component proportions, so that the mixed refrigerant can meet the requirements of different application scenes. When a low GWP value is required and high-temperature refrigeration is required, the mass ratio of R161 to R1132(E) can be more; when the combustibility is required to be low and the amount of refrigerant per unit volume is required to be high, the mass ratio of difluoromethane (R32) can be increased.

Tables 4 and 5 compare the theoretical cycle performance of the single stage refrigerant compositions of the examples with R22, R290, R410A at standard and high temperature conditions of refrigeration. Specific parameters of the refrigeration standard and the high-temperature working condition are given in table 3. Figure 2 is a single stage theoretical cycle pressure enthalpy diagram calculated under the following assumptions: the compression process is an isentropic process, and irreversible loss does not exist; no flow resistance loss exists in the refrigerant pipeline, and only heat is exchanged in the two devices; the refrigerant is in an isenthalpic process through the throttling element and does not exchange heat with the outside; and (3) calculating the condensation temperature and the evaporation temperature of the non-azeotropic refrigerant in the process, and taking the average value of the bubble point temperature and the dew point temperature.

TABLE 3 specific parameters of the calculated operating conditions

TABLE 4 comparison of Performance under Standard conditions

TABLE 5 comparison of Performance under high temperature conditions

Preferably, in the refrigerant composition, the mass fraction of difluoromethane is [ 10%, 22% ], the mass fraction of monofluoroethane is [ 50%, 61% ], and the mass fraction of trans 1, 2-difluoroethylene is [ 17%, 29% ]. See in particular examples 1-4 of tables 2, 4, 5, where the mixed refrigerant has a GWP of less than 150, a class 2 flammability safety rating, and a glide temperature of less than 2 ℃. The evaporation pressure, the condensation pressure, the pressure ratio and the exhaust temperature are equivalent to those of R22 under the standard working condition, and compared with R22, the relative volume refrigerating capacity is 1.01-1.09, the relative mass refrigerating capacity is 1.53-1.60 and the relative COP ratio is 1-1.01; the relative COP of the high-temperature working condition is basically not attenuated. Therefore, the configuration of the two devices is not required to be adjusted, the displacement of the compressor is slightly reduced, the filling amount is reduced by 34%, R290 and R22 can be directly replaced in the household air conditioner, and the household air conditioner is suitable for high-temperature environment areas such as the middle east.

Preferably, in the refrigerant composition, the mass fraction of difluoromethane is [ 30%, 44% ], the mass fraction of monofluoroethane is [ 24%, 40% ], and the mass fraction of trans 1, 2-difluoroethylene is [ 20%, 32% ]. See in particular examples 5-8 of tables 2, 4, 5, where the mixed refrigerant has a GWP of less than 300, a glide temperature of less than 2 ℃, and a class 2 flammability safety rating. The evaporation pressure, the condensation pressure and the exhaust temperature are slightly higher than R22 under the standard working condition, and compared with R22, the relative volume refrigerating capacity is 1.15-1.24, the relative mass refrigerating capacity ratio is 1.47-1.50 and the relative COP ratio is 0.99-1.00; the relative COP of the high temperature condition is slightly attenuated. The configuration of the two devices is not required to be adjusted, the displacement of the compressor is reduced by 13%, the filling amount is reduced by 31.5%, R290 and R22 can be directly replaced in the household air conditioner, and the method is suitable for areas with medium temperature environments.

Preferably, in the refrigerant composition of claim 1, the mass fraction of difluoromethane is [ 63%, 73% ], the mass fraction of monofluoroethane is [ 5%, 15% ], and the mass fraction of trans 1, 2-difluoroethylene is [ 16%, 30% ]. In particular, see examples 9-12 of tables 2, 4, and 5, when the mixed refrigerant has a GWP of less than 500, a glide temperature of less than 2 ℃, and a combustion safety rating of class 2 micro-flammability. The evaporation pressure and the condensation pressure are lower than R410A under the standard working condition, the exhaust temperature is higher than R410A by about 7 ℃, and compared with R410A, the relative volume refrigerating capacity is 0.94-0.98, the relative mass refrigerating capacity is 1.41-1.46, and the relative COP ratio is 1.03-1.04; the relative COP decay for the high temperature regime is less than R410A. The compressor displacement is increased by 6% and the filling amount is reduced by 29% without adjusting the configuration of the two devices, and the compressor can directly replace R410A in a household air conditioner and is suitable for a standard temperature environment.

The composition also comprises a stabilizer which is composed of two components, wherein the first component is one or a combination of two or more of ether compounds, and the second component is one or a combination of two or more of mercaptan, calcium sulfonate, aryl sulfide and tricresyl phosphate.

In the composition/compressor lubricant, other stabilizers may be added to ensure stability of refrigeration in the refrigeration system. The stabilizer consists of two components, wherein the first component is selected from ether compounds such as dimethyl ether, diethyl ether, diethylene glycol methyl ether, hydrofluoroether and the like, has stable performance, cannot influence refrigeration system parts, lubricating oil and the like, can ensure that monofluoroethane (R161) in the composition cannot be decomposed at high temperature, and avoids the problems of corrosion of metal materials such as copper pipes and the like and impure lubricating oil color caused by decomposition. The second component is selected from mercaptan, calcium sulfonate, aryl sulfide, tricresyl phosphate and the like, and can be used as a rust inhibitor and an antiwear agent, so that the running stability of the composition is improved. The stabilizer composition can be added into the lubricating oil of a compressor of a refrigeration system containing the composition, and the mass ratio of the stabilizer composition to the lubricating oil of the compressor is preferably 0-2% to 1, and more preferably 0.5-1.5% to 1; the stabilizer composition can also be directly added into the composition, and the mass ratio of the stabilizer composition to the composition is preferably 0-2% to 1, and more preferably 0.5-1.5% to 1.

As shown in fig. 3, in the single-stage refrigeration cycle, the low-pressure mixed refrigerant exchanges heat with the indoor air to release cold, and then the low-pressure gaseous refrigerant enters the compressor to be compressed to high-pressure high-temperature gaseous state, exchanges heat with the outdoor air through the condenser to release heat, is condensed to high-pressure liquid refrigerant, and is throttled by the throttling element to gas-liquid two-phase low-pressure refrigerant. The refrigerant composition of the invention exchanges heat, is compressed and throttled in the single-stage compression household air conditioner, and replaces R290, R22 or R410A refrigerants.

As shown in fig. 4, in the two-stage refrigeration cycle, the refrigeration circuit is provided with a gas-liquid separator, the low-pressure environment-friendly refrigerant composition exchanges heat with indoor air to release cold, then the low-pressure gaseous environment-friendly refrigerant composition enters the compressor 1 to be compressed to a medium-pressure gas state by one stage, then is mixed with the medium-pressure gaseous refrigerant of the gas-liquid separator to be compressed by two stages, is in a high-pressure high-temperature gas state, exchanges heat with outdoor air by the condenser to release heat, is condensed to a high-pressure liquid refrigerant, enters the gas-liquid separator as a gas-liquid two-phase medium-pressure refrigerant by the throttling element, the medium-pressure gaseous refrigerant enters the compressor 1 to supplement air, and the medium-pressure liquid refrigerant enters the evaporator by the other throttling element. The refrigerant composition exchanges heat, is compressed and throttled in the double-stage compression household air conditioner, and replaces R290, R22 or R410A refrigerants.

The refrigerant composition can be applied to household air-conditioning systems. The domestic air conditioning system adopts a single-stage or double-stage compression refrigeration cycle, and comprises an evaporator, a condenser, a compressor, a throttling element and other auxiliary refrigeration accessories, wherein all the refrigeration elements are connected into a closed loop, and 1-6 refrigerant fluid flows in the loop.

The above description is only exemplary of the present disclosure and should not be taken as limiting the disclosure, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure. The foregoing is only a preferred embodiment of the present disclosure, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present disclosure, and these modifications and variations should also be regarded as the protection scope of the present disclosure.

Claims

1. A refrigerant mixture characterized by:

comprising a mixed refrigerant comprising a first component, a second component, and a third component, wherein: said first component is difluoromethane, said second component is monofluoroethane, and said third component is trans 1, 2-difluoroethylene;

in terms of mass percentage, the mass ratio of the difluoromethane to the mixed refrigerant is [ 10%, 72% ], the mass ratio of the monofluoroethane to the mixed refrigerant is [ 6%, 70% ], and the mass ratio of the trans 1, 2-difluoroethylene to the mixed refrigerant is [ 4%, 30% ].

2. Refrigerant blends as in claim 1, wherein:

the mass ratio of the difluoromethane to the mixed refrigerant was [ 10%, 22% ], the mass ratio of the monofluoroethane to the mixed refrigerant was [ 50%, 61% ], and the mass ratio of the trans 1, 2-difluoroethylene to the mixed refrigerant was [ 17%, 29% ].

3. Refrigerant blends as in claim 1, wherein:

the mass ratio of the difluoromethane to the mixed refrigerant was [ 30%, 44% ], the mass ratio of the monofluoroethane to the mixed refrigerant was [ 24%, 40% ], and the mass ratio of the trans 1, 2-difluoroethylene to the mixed refrigerant was [ 20%, 30% ].

4. Refrigerant blends as in claim 1, wherein:

the mass ratio of the difluoromethane to the mixed refrigerant was [ 63%, 72% ], the mass ratio of the monofluoroethane to the mixed refrigerant was [ 6%, 15% ], and the mass ratio of the trans 1, 2-difluoroethylene to the mixed refrigerant was [ 16%, 30% ].

5. Refrigerant blends according to any of claims 1-4, wherein:

the refrigerant composition also comprises a stabilizer, wherein the mass ratio of the stabilizer to the mixed refrigerant is 0% to 1-2% to 1.

6. Refrigerant blends as in claim 5, wherein:

the stabilizer comprises two components, wherein the first component comprises one or two or more of ether compounds in combination, and the second component comprises one or two or more of mercaptan, calcium sulfonate, aryl sulfide and tricresyl phosphate in combination.

7. An air conditioning system characterized by:

comprising the refrigerant mixture of any of claims 1-6.

8. The air conditioning system of claim 7, wherein:

the air conditioning system is in single-stage or double-stage compression refrigeration circulation.

9. The air conditioning system of claim 7, wherein:

the air conditioning system is a household air conditioning system.