CN116601259A

CN116601259A - Heat pump refrigerant

Info

Publication number: CN116601259A
Application number: CN202180082289.4A
Authority: CN
Inventors: 约翰·爱德华·普尔; R·L·鲍威尔
Original assignee: RPL Holdings Ltd
Current assignee: RPL Holdings Ltd
Priority date: 2020-10-22
Filing date: 2021-10-21
Publication date: 2023-08-15
Also published as: GB202103406D0

Abstract

The present invention provides a refrigerant consisting of or consisting essentially of: a) A non-flammable, high volatile component consisting of carbon dioxide, and b) a non-flammable, low volatile component selected from the group consisting of: HFO1224yd (Z), HFO1224yd (E), HFO1233zd (Z), HFO1233xf, HFO1336mzz (E), HFO1336mzz (Z), 2-bromo-3, 3-trifluoroprop-1-ene, and mixtures thereof; c) A medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO1225ye (Z), HFO1243zf, and mixtures thereof; and d) an optional component selected from the group consisting of: HFC227ea, HFC152a, HFC32, and mixtures thereof.

Description

Heat pump refrigerant

Technical Field

The present invention relates to heat pump refrigerants that can have wide inherent and very wide glide refrigerant compositions, and particularly (but not exclusively) can have compositions having GWP of less than 400, preferably less than 150, and more preferably less than 10. Refrigerants are used in a variety of applications, including refrigeration, air conditioning, and heat pump processes. These applications are collectively referred to as heat pumps.

Embodiments of the present invention operate in a reverse rankine cycle (Reverse Rankine Cycle, RRC).

Background

RRC devices are well known to those skilled in the art. In its simplest form, it consists of an evaporator in which a liquid/gas dual phase refrigerant evaporates at a lower pressure and temperature, thereby absorbing heat from adjacent fins. Vapor from the evaporator is drawn into a compressor where it is compressed to a higher pressure and higher temperature. The vapor then enters a condenser where it condenses into liquid aluminum by rejecting heat from the copper adjacent the fins. The higher pressure and temperature liquid aluminum passes through an expansion device, reducing its pressure to that of an equivalent evaporator, and a portion of the liquid aluminum evaporates, thereby reducing its temperature. The two-phase mixture of liquid aluminum and vapor enters the evaporator to continue the cycle.

Another name for RRC is ' vapor recompression ' compression ' cycle (VRC).

The non-azeotropic refrigerant composition evaporates and condenses at a constant pressure within a certain temperature range. This range is referred to as 'temperature slip' or simply 'slip'. However, it has been found in the prior art that the term 'slip' has a confusing and different definition. For example, the term 'slip' may be defined as the temperature difference between the bubble point and the dew point at a specified constant pressure. In this way, the "slip" is purely the thermodynamic property of the refrigerant and is independent of the equipment and operating conditions. In this specification, the difference between the bubble point and the dew point at an absolute pressure value of 1 atmosphere is referred to as the 'thermodynamic slip' of the blend.

Alternatively, 'slip' in the evaporator may refer to the difference between the inlet temperature and the dew point, which is necessarily less than the thermodynamic slip and depends on the operating conditions and equipment design and the composition of the blend. In the condenser, slip is the difference between dew point and bubble point, and also depends on operating conditions, equipment design, and the composition of the blend.

In this specification, the term "intrinsic temperature slip" refers to the temperature difference between the start and end of a two-phase heat transfer region in an evaporator or condenser, assuming that there is no pressure drop. If the evaporator or condenser has 'flooded' (i.e., both liquid and gas phases are present along the entire DX heat exchanger tube, then slippage is the temperature difference between the ends of the heat exchanger. This value will be smaller than the value given by the previous definition.

In some heat pumps, refrigerant slip may be utilized to increase performance using RRC/VRC occurrences known as Lorentz cycles. In this specification, references to RRC/VRC names will also cover the lorentz cycle.

In this specification, thermodynamic temperature glide can be categorized as follows:

1. slip of negligence-less than 0.5K

2. Small slip-0.5K to 2.0K

3. Moderate slip-greater than 2.0K to 5.0K

4. Wide slip-greater than 5K to 10.0K

5. Very wide slip-greater than 10.0K

The compositions of the present invention may have a broad or very broad thermodynamic temperature glide.

In a real heat exchanger, there must be a pressure drop to keep the refrigerant flowing. This causes a 'pressure induced temperature glide'. The inherent slip is combined with the pressure induced slip to obtain the actual slip of copper. In the evaporator, the intrinsic slip and the pressure-induced slip act in opposite directions, so that in the two-phase evaporation region, the actual temperature slip is smaller than the intrinsic temperature slip. But in the two-phase flow condensation zone the intrinsic slip is in the same direction as the pressure induced slip. Thus, the effects of the two slips are additive such that the actual temperature slip is greater than the natural temperature slip. For convenience, in this specification, the term "slip" will be considered to mean "inherent temperature slip" unless otherwise specified. This meaning is consistent with the routine and practice of those skilled in the art, in which the effect of stress-induced slip is normally neglected. If the net slip created by the combination of the inherent slip and the pressure induced slip is considered, it will be referred to as the 'actual slip'.

If a zeotropic is registered by the American society of heating and refrigeration Engineers (American Society of Heating and Refrigeration Engineers, ASHRAE), it is given a "R4 XX" number. Although some blends are non-azeotropic in form, such as R404A and R410A, they have a slip typically less than 1K and are classified as "near-azeotropic". For practical purposes, it may be considered an azeotrope.

Azeotrope-like compositions having slip less than 5K, and preferably less than 1K, are believed to be necessary for efficient and reliable operation of heat pump systems. The inventors have unexpectedly found that non-azeotropic compositions having thermodynamic slips of greater than 5K and even greater than 10K can be satisfactorily used in specially designed units.

A variety of refrigerants are commercially available for use in heat pump equipment. For coolers with condensing pressures less than 2 bar absolute, a low volatility refrigerant such as R123 (bp 28 ℃ C.) may be used. For coolers and medium temperature refrigeration, R1234ze (E) may be used, while for automotive air conditioning, R1234yf may be preferred. Some of these refrigerants have certain disadvantages. R123 has an ODP of 0.06 and GWP of 77 and is thus being phased out. R1233zd (E) (bp 18.3 ℃ C. ODP 0; GWP 1) is a potential alternative to R123, but its condensing pressure may exceed 2 bar absolute.

R404A and R507 are widely used for refrigeration, and R410A is widely used for air conditioning and heat pump. These are excellent refrigerants in terms of energy efficiency, incombustibility, low toxicity, and thermodynamic properties. However, it has a Global Warming Potential (GWP) of greater than 2000 and is therefore considered environmentally unacceptable. Regulations are being introduced worldwide to reduce their use and eventually may be eliminated. The European Union (EU) and other regions have imposed GWP quotas and/or tax liabilities to gradually reduce the availability of R404A, R and R410A and other HFC refrigerants. The EU fluorine-containing gas aluminum regulations greatly reduce the marketable aluminum product of refrigerants based on their GWP. EU has also limited some applications using refrigerants with GWP above 150.

R32 is being introduced as a substitute for R410A, but still has an unacceptably high GWP of 675 and is flammable (ASHRAE rating A2L). R13B1 (bp-58 ℃ C.) is an extremely low temperature refrigerant having an extremely high ODP of 10 (on the same scale, the ODP of R11 is 1) and GWP of 6900. R22 is an excellent refrigerant but is phased out because its ODP is 0.055.

R1234yf, which has a very low global warming potential, is a good thermodynamic match for R134a, which is highly global warming, and has replaced the latter in mobile (vehicular) air conditioning systems. Nevertheless, R1234yf is flammable, its ASHRAE safety class is A2L, and its flammability makes industry resistant to adoption, with some vehicle manufacturers strongly advocated carbon dioxide, although operating pressures of at least 100 bar, low energy efficiency, ease of performance degradation even with slight leaks, and high compressor starting torque, can lead to small internal combustion engine stall.

Ammonia, hydrocarbons, and carbon dioxide are well-known streams of aluminum for refrigeration and air conditioning systems and have significantly lower GWP than Hydrofluorocarbons (HFC). However, it is also toxic or flammable or both (in the case of ammonia). In addition to the significant safety hazards present in public places such as supermarkets, flammable hydrocarbons can only be safely used in conjunction with the second refrigeration circuit. This reduces energy efficiency, increases costs, and severely limits the maximum cooling load of hydrocarbons due to low loadings. CO ₂ Must be used in a transcritical state on the high pressure side of the system to allow heat to be rejected to ambient air. The pressure is usually over 100 bar absolute, resulting in energy losses and investment costs which are also significantly higher than in the conventional R404A, R507 and R410A systems.

Although HFC's have less effect on global warming than CO ₂ And methane, but HFC is governed by fluorine-containing gas and aluminum regulations of copper EU and montreal protocol base calix amendment (Kigali amendment to the Montreal Protocol) so that HFC usage is gradually reduced and eventually can be eliminated. Worldwide global use of safe, effective and practical HFCs has become customary, but the restrictions of international regulations restricting the use of HFCs are increasing, and are introducing great uncertainty to Original Equipment Manufacturers (OEMs) in the selection of refrigerants that can be used for long periods of time. This uncertainty is inhibiting the development of improved heat pump technology. An object of the present invention is to solve the improved heat pumpDevelopment problems of the technology.

The heat pump technology starts from the birth of the middle of the 19 th century, and is always dominated by a single component or azeotropic refrigerant, which continues to date. In the 70 s of the 19 th century, ammonia became the primary industrial refrigerant, followed by carbon dioxide, sulfur dioxide, methyl chloride and hydrocarbons. The introduction of the much safer CFCs and HCFCs and the introduction of the single component refrigerants CFC-12, CFC-114 and HCFC-22 and azeotropes R500 and R502 in the 30 s of the 20 th century led to the rapid development of refrigeration and air conditioning.

The apparatus is specifically designed to optimize the performance of the single component and azeotropic refrigerants, so other new refrigerants are expected to meet these engineering guidelines. The essential feature is that these refrigerants evaporate and condense at a constant temperature and at a constant pressure. This feature is emphasized by the saturation table, superheat table, and pressure-enthalpy diagram table provided by the refrigerant suppliers and is used throughout the industry by OEMs and maintenance technicians to optimize existing plant operation. However, these restrictive guidelines, which are affected by the development of copper early refrigerants, prevent the use of new refrigerants that combine the features of low environmental impact and low in-use hazard and acceptable heat pump performance. The present specification discloses refrigerants with thermodynamic temperature slip greater than 5K, so-called "wide-slip refrigerants" or even higher-slip very wide-slip refrigerants, which overcome the problem of how to provide new refrigerants that combine the features of low environmental impact and low harm and acceptable heat pump performance when in use.

In the present specification, the numerical value of Global Warming Potential (GWP) refers to a 100-year time course integral value (Integrated Time Horizon, ITH) as contained in the fourth evaluation report (Inter-Governmental Panel on Climate Change Fourth Assessment Report) of the Inter-government climate change committee.

Disclosure of Invention

According to the invention, the refrigerant consists of or consists essentially of:

a) Non-flammable high volatile component carbon dioxide

b) A nonflammable, low volatile component selected from the group consisting of: HFO1224yd (Z), HFO1224yd (E), HFO1233zd (Z), HFO1233xf, HFO1336mzz (E), HFO1336mzz (Z), 2-bromo-3, 3-trifluoroprop-1-ene; or mixtures thereof;

c) A medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO-1225ye (Z), HFO1243zf, or mixtures thereof; a kind of electronic device with high-pressure air-conditioning system

d) An optional component selected from: HFC-227ea, HFC-152a, HFC-32 or mixtures thereof.

The refrigerant of the present invention may have a global warming potential of up to 400.

In this specification, percentages or other amounts are by mass unless otherwise indicated. The amount is selected from any range specified to total 100%. The pressure is given in absolute pressure bar (bara).

The term 'hydro-fluoro-olefin' may be abbreviated as 'HFO' and includes compounds containing hydrogen, fluorine and carbon atoms and optionally chlorine and bromine atoms.

The term "consisting of" as used in this specification means a composition comprising only the ingredients, without regard to any trace amounts of impurities.

The term "consisting essentially of" as used in this specification means a composition consisting of the recited ingredients, wherein small amounts of any other ingredients may be added without substantially altering the basic refrigerant properties of the composition. Such compositions include those consisting of the ingredients. Compositions composed of such ingredients may be particularly advantageous.

The present invention relates to extremely low GWP blends, which are particularly (but not exclusively) compositions useful in new refrigeration, air conditioning and heat pump systems.

The ozone depletion potential of the blend is zero and therefore has no adverse effect on stratospheric ozone. The blend additionally or alternatively has a GWP of 400 or less, preferably 150 or less and more preferably less than 10.

One method for ranking the relative combustibility of a refrigerant is provided by the ASHRAE 34 committee's scale, which simply classifies the refrigerant into four flammability categories,

the blend may have an ASHRAE safety classification of A1 (non-flammable) or A2L (less flammable) that provides a novel combination of characteristics in combination with low GWP and high efficiency of less than 400, preferably less than 150 and most preferably less than 10. The invention is particularly concerned with refrigerant compositions containing one or more hydrofluoro-olefins (HFOs).

ASHRAE scale does not further distinguish between the degrees of flammability within each category. However, copper can be made by considering the Lower Flammability Limit (LFL) of the blend. LFL of refrigerant vapor in air at atmospheric pressure and temperature is the lower limit of the vapor ignitable concentration range. If the vapor fails to ignite, it does not have LFL at temperatures up to 60 ℃ and its ASHRAE rating is class 1.

The refrigerant of the present invention may be referred to as a wide-slip or very wide-slip refrigerant.

In one embodiment, the high volatile component has a vapor pressure of 1atm at a temperature at least 10 ℃ lower than the medium volatile component, and the medium volatile component has a vapor pressure of 1atm at a temperature at least 10 ℃ lower than the low volatile component.

In embodiments, the high volatile component may have a vapor pressure of 1atm at a temperature in the range of-80 ℃ to-45 ℃.

In one embodiment, the medium volatile component may have a vapor pressure of 1atm at a temperature in the range of-35 ℃ to-15 ℃.

In one embodiment, the low volatile component may have a vapor pressure of 1atm at a temperature in the range of 0 ℃ to 40 ℃.

In embodiments, the highest and lowest volatile components are non-flammable and the medium volatile component may be flammable.

The presence of the non-flammable component inhibits the flammability of one or more of the flammable components to render the blend non-flammable, which has the effect of increasing the Lower Flammability Limit (LFL) of the blend. Combustible compositions having ASHRAE safety class A2L have a higher GWP due to the presence of one or more HFC components, possess additional beneficial characteristics for specific applications, such as replacing the "HFC" with a lower global warming blend, and similar technical characteristics.

At the beginning of a vapor or liquid aluminium leak, for example under conditions specified according to the ASHRAE 34 standard flammability test standard, highly volatile non-flammable CO ₂ Inhibit the flammability of R32 (if present) and flammable HFO components and R152a (if present). As leakage proceeds, CO ₂ And the concentration of R32 (if present) decreases, while the concentration of flammable HFO and R152a (if present) and non-flammable HFO increases.

Incombustible CO present in early stages of leakage ₂ And the presence of non-flammable HFOs late in the leak will inhibit the flammability of the higher volatile HFOs and HFC32 and HFC152a, if present. Vapor and liquid aluminum with higher concentrations of non-flammable components will have higher LFLs and therefore lower flammability, although ASHRAE class is still 2L. Preferably, the ratio of non-flammable components to flammable components throughout the leak is such that both the vapor composition and the liquid aluminum composition are always non-flammable, i.e., the compositions are in accordance with ASHRAE safety classification a1 1.

In particular, the invention relates to a highly volatile nonflammable component CO ₂ Low volatility (boiling point)>0 ℃ and extremely low GWP<10 Blends of non-flammable HFO components and medium volatile components (boiling point about-19 ℃) which are a range of low hazard, environmentally benign blends that can replace the "heat pump applications used today in a wide range of applications including but not limited to refrigeration, vehicle and room air conditioning, heat pump and low pressure <2 bar absolute) of the cooling medium commercially available from a chiller) and establishes a common foundation. Carbon dioxide/low volatility HFO blends contain medium volatility components (boiling point>-53 deg.c<-10 ℃ to give the blend the characteristics necessary for the specific heat pump application.

We have found that such refrigerant compositions can be used in heat pump applications where the currently employed flow aluminum having unacceptably high GWP or ODP or flammability includes, but is not limited to, R13B1, R32, R410A, R404A, R, R290 (propane), R22, R1234yf, R600 (butane), R600a (isobutane), HFO1224yd (Z), HFO1224zd (E), HFO1233zd (E), HFO1234ze (E), HFO1336mzz (Z) and HFO1336mzz (E), but some of these flow aluminum may be a component of the refrigerant composition.

In one embodiment, the refrigerant may consist of or consist essentially of:

high volatile components, medium volatile components, and low volatile components; wherein the high volatile component has a vapor pressure at least 1 atmosphere greater than the medium volatile component; and the low volatile component has a vapor pressure at least 1atm lower than the medium volatile component.

In one embodiment, the refrigerant composition consists of or consists essentially of:

A nonflammable, highly volatile component consisting of carbon dioxide;

a nonflammable, low volatile component selected from the group consisting of: HFO1224yd (Z), HFO1224yd (E), HFO1233zd (Z), HFO1233xf, HFO1336mzz (E), HFO1336mzz (Z), 2-bromo-3, 3-trifluoroprop-1-ene, and mixtures thereof;

a medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO1225ye (Z), HFO1243zf, and mixtures thereof;

optionally one or more components selected from the group consisting of: HFC227ea, HFC32 and HFC152a.

In one embodiment, the refrigerant consists of or consists essentially of:

a) A nonflammable, highly volatile component consisting of carbon dioxide;

b) A nonflammable, low volatile component selected from the group consisting of: HFO1224yd (Z), HFO1224yd (E), HFO1233zd (Z), HFO1233xf, HFO1336mzz (E), HFO1336mzz (Z), 2-bromo-3, 3-trifluoroprop-1-ene, and mixtures thereof;

c) A medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO-1225ye (Z), HFO1243zf, and mixtures thereof; a kind of electronic device with high-pressure air-conditioning system

d) An optional HFC selected from the group consisting of: HFC227ea, HFC152aHFC, and mixtures thereof;

Wherein the amount of the high volatile component is in the range of 5 wt% to 85 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 95 wt%;

wherein the amount of the medium volatile component is in the range of 10 wt% to 90 wt%;

wherein HFC32 is present in an amount in the range of 2 weight percent to 59 weight percent;

wherein HFC227ea is present in an amount in the range of 1 wt% to 12.4 wt%;

wherein HFC152a is present in an amount ranging from 2 to 10 weight percent.

Wherein the amounts of these ingredients are selected from the stated ranges up to a total of 100% by weight.

The sum of the percentage weighted GWP fractions of the components may not exceed 400.

In one embodiment, the refrigerant consists of or consists essentially of:

a) A nonflammable, highly volatile component consisting of carbon dioxide,

d) An optional HFC selected from the group consisting of: HFC32, HFC227ea, HFC152a, and mixtures thereof;

wherein the amount of the high volatile component is in the range of 5 wt% to 60 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 40 wt%;

wherein the amount of the medium volatile component is in the range of 10 wt% to 65 wt%;

wherein HFC227ea is present in an amount in the range of 1 wt% to 12.4 wt%;

wherein HFC152a is present in an amount in the range of 2 weight percent to 5 weight percent;

In one embodiment, the refrigerant consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

c) A medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO-1225ye (Z), and HFO1243zf, and mixtures thereof; a kind of electronic device with high-pressure air-conditioning system

d) An optional HFC selected from the group consisting of: HFC32, HFC152a and HFC227ea and mixtures thereof;

wherein the amount of the high volatile component is in the range of 5 wt% to 30 wt%;

wherein HFC32 is present in an amount in the range of 22.2 weight percent to 59 weight percent;

wherein HFC227ea is present in an amount in the range of 4.7 wt% to 12.4 wt%;

wherein HFC152a is present in an amount ranging from 2 to 10 weight percent;

a kind of electronic device with high-pressure air-conditioning system

The sum of the percentage weighted GWP fractions of the components may be greater than 150, but not more than 400.

In one embodiment, the refrigerant consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

wherein HFC32 is present in an amount in the range of 2 weight percent to 22 weight percent;

wherein the HFC227ea is present in an amount in the range of 1 wt% to 4.7 wt%;

a kind of electronic device with high-pressure air-conditioning system

The sum of the percentage weighted GWP fractions of the components may be greater than 14, but not greater than 150.

In one embodiment of the invention, the refrigerant consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

wherein the amount of the medium volatile component is in the range of 10 wt% to 60 wt%;

wherein the amount of HFC32 is in the range of 2 weight percent to 22 weight percent;

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

Wherein the amount of the high volatile component is in the range of 6 to 25 wt%;

wherein the amount of the low volatile component is in the range of 7 wt% to 30 wt%;

wherein the amount of the medium volatile component is in the range of 40 wt% to 60 wt%;

wherein the amount of HFC32 is in the range of 10 weight percent to 21.5 weight percent;

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

Wherein the amount of the high volatile component is in the range of 5 wt% to 15 wt%;

wherein the amount of the low volatile component is in the range of 6 wt% to 35 wt%;

Wherein the amount of the medium volatile component is in the range of 46 to 55 wt%;

wherein the amount of HFC32 is in the range of 15 weight percent to 21.5 weight percent;

In one embodiment, the refrigerant consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC227ea；

wherein the amount of HFC227ea is in the range of 2 wt% to 4.7 wt%;

The sum of the percentage weighted GWP fractions of the components may be greater than 64, but not greater than 150.

a) A nonflammable, highly volatile component consisting of carbon dioxide,

wherein the amount of the medium volatile component is in the range of 10 wt% to 75 wt%; a kind of electronic device with high-pressure air-conditioning system

The sum of the percentage weighted GWP fractions of the components may not exceed 10.

a) A nonflammable, highly volatile component consisting of carbon dioxide,

Wherein the amount of the high volatile component is in the range of 10 wt% to 50 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 35 wt%;

wherein the amount of the medium volatile component is in the range of 12 to 70 wt%; a kind of electronic device with high-pressure air-conditioning system

a) Incombustible high volatile components consisting of CO ₂ Composition;

Wherein the amount of the high volatile component is in the range of 10 wt% to 40 wt%;

wherein the amount of the medium volatile component is in the range of 15 wt% to 55 wt%;

wherein the amount of the low volatile component is in the range of 7 wt% to 25 wt%; a kind of electronic device with high-pressure air-conditioning system

a) Incombustible high volatile components consisting of CO ₂ Composition;

Wherein the amount of the high volatile component is in the range of 20 wt% to 40 wt%;

Wherein the amount of the medium volatile component is in the range of 30 wt% to 55 wt%;

An embodiment of the present invention provides a refrigerant having a GWP of less than 400, which refrigerant is suitable for systems including components having rated pressures for R32 and R410A, which refrigerant may be used in new split air conditioning units or retrofitted into existing split air conditioning units.

In one embodiment of the present invention, the refrigerant suitable for retrofitting pure R32 in an existing split heat pump unit consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

Wherein the amount of the high volatile component is in the range of 8 wt% to 19 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 8 wt%;

wherein the amount of the medium volatile component is in the range of 39 wt% to 51 wt%;

wherein the amount of HFC32 is in the range of 35 weight percent to 44 weight percent;

wherein the amounts of these ingredients are selected from the ranges mentioned up to a total of 100% by weight

Wherein the blend has a bubble point vapor pressure at 40 ℃ of no more than 30 bar absolute.

The sum of the percentage weighted GWP fractions of the components may be greater than 14, but not greater than 300.

An embodiment of the present invention provides a refrigerant having a GWP of less than 150 that is suitable for use in refrigeration applications currently serviced by R404A. Preferred blends have bubble point pressures of no more than 30 bar absolute at 35 ℃. Even more preferred blends have bubble point pressures of no more than 20 bar absolute at 35 ℃.

In one embodiment of the present invention, the refrigerant suitable for the current refrigeration application using R404A consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) HFC32, HFC227ea or mixtures thereof,

wherein the amount of the high volatile component is in the range of 10 wt% to 35 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 20 wt%;

wherein the amount of the medium volatile component is in the range of 40 wt% to 80 wt%;

wherein HFC32 is present in an amount in the range of from 18 weight percent to 22 weight percent;

wherein the HFC227ea is present in an amount in the range of 2 wt% to 4.5 wt%;

Wherein the blend has a bubble point vapor pressure of no more than 30 bar absolute at 35 ℃.

The sum of the percentage weighted GWP fractions of the components may not exceed 150.

An embodiment of the present invention provides a refrigerant having a GWP of less than 150 that is suitable for use in refrigeration applications currently serviced by R410A and HFC 32. Preferred blends have bubble point pressures at 35 ℃ of not more than 35 bar absolute. Even more preferred blends have bubble point pressures of no more than 25 bar absolute at 35 ℃.

In one embodiment of the present invention, the refrigerant suitable for the refrigeration application currently in use with HFC32 and R410A consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

c) A medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO1225ye (Z), HFO1243zf, and mixtures thereof; a kind of electronic device with high-pressure air-conditioning system

d) HFC32, HFC227ea or mixtures thereof,

wherein the amount of the high volatile component is in the range of 8 wt% to 25 wt%;

wherein the amount of the medium volatile component is in the range of 35 wt% to 70 wt%;

wherein the HFC227ea is present in an amount in the range of 2 wt% to 5 wt%;

wherein the amounts of the ingredients are selected from the ranges to a total of 100 wt.%;

a kind of electronic device with high-pressure air-conditioning system

Wherein the blend has a bubble point vapor pressure at 35 ℃ of no more than 35 bar absolute.

An embodiment of the present invention provides a refrigerant having a GWP of less than 10 that is suitable for use in refrigeration applications currently serviced by R404A. Preferred blends have bubble point pressures of no more than 30 bar absolute at 35 ℃. Even more preferred blends have bubble point pressures of no more than 20 bar absolute at 35 ℃.

a) Incombustible high volatile components consisting of CO ₂ Composition;

Wherein the amount of the high volatile component is in the range of 9 wt% to 35 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 12 wt%;

Wherein the amount of the medium volatile component is in the range of 39 wt% to 62 wt%;

The sum of the percentage weighted GWP fractions of the components may be greater but not more than 10.

In one embodiment of the present invention, a refrigerant having a GWP of less than 10 is provided that is suitable for current service by R410A and R32 Is used for freezing. Preferred blends have bubble point pressures of no more than 45 bar absolute at 35 ℃. Even more preferred blends have bubble point pressures at 35 ℃ of no more than 35 bar absolute.

In one embodiment of the present invention, a refrigerant suitable for the current heat pump application using R410A or R32 is provided, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) Wherein the amount of the high volatile component is in the range of 9 to 30 wt%;

wherein the amount of the low volatile component is in the range of 5 wt% to 25 wt%;

Wherein the blend has a bubble point vapor pressure at 35 ℃ of no more than 40 bar absolute.

For heat pump applications where equipment coverage is an important factor, such as marine refrigeration or air conditioning, a high capacity refrigerant may be preferred, but may require a high pressure component rated for, for example, 100 bar. Although pure CO operating in a transcritical cycle ₂ Higher capacities may be provided but the energy efficiency may be lower than the blends provided by the present invention operating in reverse rankine cycle.

An embodiment of the present invention provides a refrigerant having a GWP of less than 10 that is suitable for high capacity heat pump applications currently served by R404A, R410A and R32.

In one embodiment of the present invention, a refrigerant suitable for the current refrigeration application using R404A, R410A or R32 consists of or consists essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) Wherein the amount of the high volatile component is in the range of 70 wt% to 85 wt%;

wherein the amount of the medium volatile component is in the range of 5 wt% to 25 wt%;

The Hydrofluoroolefins (HFOs) used in the present invention include:

HFO1234yf (2, 3-tetrafluoroprop-1-ene);

HFO1234ze (E) (E-1, 3-tetrafluoroprop-1-ene);

HFO1216 (hexafluoropropylene);

HFO1243zf (3, 3-trifluoroprop-1-ene);

HFO1225ye (Z) (Z-1, 2, 3-pentafluoroprop-1-ene);

HFO1224yd (Z) (Z-1-chloro-2, 3-tetrafluoropropene);

HFO1233zd (E) (E-1-chloro-3, 3-trifluoro-prop-1-ene);

HFO1233zd (Z) (Z-1-chloro-3, 3-trifluoro-prop-1-ene);

HFO1233xf (2-chloro-3, 3-trifluoro-prop-1-ene);

2-bromo-3, 3-trifluoro-prop-1-ene;

HFO1336mzz (Z) (Z-1, 4-hexafluoro-but-1-ene;

HFO1336mzz (E) (E-1, 4-hexafluoro-but-1-ene);

HFO1234ze(Z)；

HFO1234ze (Z) with a boiling point of 9.8 ℃ can be considered a low volatility HFO, but it does not meet the requirement in this specification that the low volatility HFO be nonflammable. However, nonflammable mixtures of HFO1234ze (Z) with other nonflammable low volatility HFOs may be used in the compositions of the present invention.

HFO1224 may be a preferred hydrofluorocarbon.

The values of GWP for the low volatility HFOs listed are very low, for example in the range of 1 to 18.

The apparatus described in this specification includes a condenser and an evaporator. Such devices may be 'DX' in which the refrigerant flows from one end of a 'tube' to the other. Ruler-shaped tube' is a commonly used term, which is a section of tube used in heat exchangers.

In an embodiment, a heat pump apparatus comprises a circuit comprising:

an evaporator, a compressor, a condenser, an expansion device and circulating refrigerant flow aluminum as claimed in the invention;

The heat pump apparatus further comprises a refrigerant flow aluminum according to the present invention;

wherein the loop includes one or more of the following components:

a cooling member for cooling the compressor;

an internal heat exchanger (IHX) transfers heat from the high pressure stream of aluminum flowing between the condenser and the expansion device to the low pressure stream of aluminum flowing between the evaporator and the compressor.

The circuit may further comprise a reservoir for liquid aluminum coolant. The reservoir may be located downstream of the evaporator.

CO in refrigerant blends ₂ The disadvantage of (2) may be to increase the discharge temperature and decrease the energy efficiency of the composition. High discharge temperatures can cause excessive compressor wear, reduced reliability, and operational life.

Means may be provided to cool the compressor to control the discharge temperature of the compressor to maintain it below a maximum temperature, for example below 110 ℃, preferably below 100 ℃, and to obtain copper at least as efficient as using CO ₂ The existing equipment of R32, R410A, R, 404A, R507, R1234yf, R134a, R1234ze (E), R123, R1336mzz (Z), R290, R600 and R600a are equivalent.

Various cooling members may be employed to cool the compressor. A combination of two or more cooling members may be provided.

Excessive cooling can also cause compressor damage. If the liquid aluminum refrigerant is still present at the end of compression, the liquid aluminum refrigerant may damage the discharge valve immediately before entering the discharge line or, in extreme cases, cause a 'liquid aluminum lock' that may damage the compressor drive mechanism.

In an advantageous embodiment of the invention, the discharge temperature and the vapor temperature leaving the compressor may be higher than the dew point of the refrigerant at this point of the circuit, for example 5 ℃ or higher than the dew point, for example 10 ℃ or higher than the dew point. This serves to minimize the risk of damage to the compressor by the liquid aluminium.

The cooling means may comprise one or more of the following:

1. a liquid aluminum injector adapted to inject a liquid aluminum refrigerant into the compressor;

2. a cooling jacket in thermal contact with the compressor;

3. the compressor has channels for flowing aluminum in the compressor head and/or the main aluminum to remove heat generated by refrigerant compression.

4. And injecting liquid aluminum refrigerant, wherein the liquid aluminum refrigerant is extracted from a position between the tail end of the condenser and the expansion device and passes through a cooling sleeve or a compressor head and/or a channel in the main aluminum.

5. Liquid aluminum refrigerant from between the condenser end and the expansion device is injected into the compressor discharge pipe.

6. A cooling tube in thermal contact with the compressor;

7. a heat pipe in thermal contact with the compressor;

8. thermosiphon in thermal contact with compressor

9. Means for injecting cold vapor into the compressor.

Other cooling means may be employed.

The liquid aluminum injector may be configured to inject liquid aluminum refrigerant into the suction line or into the compression space of the compressor.

Various compressor types can be used in conjunction with the wide slip, low GWP blends of the present invention. Positive displacement type compressors may include, but are not limited to, scroll, clogs, movable vane, rotary rolling piston, screw, vane, and reciprocating compressors. Dynamic types of compression may include, but are not limited to, centrifugal and axial compression. The electric motor driving the compressor may be contained within a shared housing aluminum. This configuration is referred to as a hermetic or semi-hermetic compressor. If the motor is located outside the compressor shell aluminum, this is referred to as an open compressor. For the blends of the present invention, to reduce discharge temperature, preferred compressor designs include liquid aluminum injection feeds: injected into the suction inlet or into the compressed aluminum volume. Alternatively, cold vapor may be injected into the compressed aluminum product.

The evaporator may be 'flooded'. In this specification, flooded evaporators mean that the exiting refrigerant may be a two-phase mixture of liquid aluminum and vapor. In many refrigeration and air conditioning apparatuses of today, the refrigerant can be completely evaporated and then further superheated, for example 3 to 10K, for example 5K, to ensure that liquid aluminium does not enter the suction line and is subsequently fed to the compressor. This is usually achieved by using a thermostatic expansion valve whose degree of opening varies in response to a gas storage sensor attached to the suction line after the evaporator. The valve is adjusted to set the superheat of the vapor leaving the compressor to a specific value, for example 3 to 10K, for example 5K. If the evaporator cooling load increases, the sensor detects an overheating of copper above 5K, and the valve is opened to allow more refrigerant to enter the evaporator, thereby recovering the overheating to a preset value. It is understood by those skilled in the art that if superheated vapor enters the compressor, the discharge vapor may also be superheated.

However, for the wide and very wide glide refrigerants disclosed in this specification, it may be impractical to superheat the refrigerant. Thus, the evaporator may be flooded such that the exiting mixture enters the suction line as two-phase liquid aluminum/vapor. To evaporate additional quantities of liquid aluminum in the suction line, an internal heat exchanger (IHX) may be added to transfer the heat of the hotter high pressure refrigerant returning from the condenser to the expansion device. The refrigerant leaving the IHX may be superheated so that it is substantially free of liquid phase, thereby ensuring that no liquid aluminum enters the compressor. Alternatively and advantageously, the refrigerant leaving the IHX may still contain some liquid aluminum, which may enter the compressor where it flash as the refrigerant temperature rises due to compression or heat from the electric motor in the closed unit. This arrangement reduces the discharge temperature of the refrigerant to a temperature below that which would be obtained if no liquid aluminum entered the compressor. This can be used to protect the compressor from excessive wear caused by overheating.

The discharged refrigerant can be superheated by at least 5K and dried to avoid damaging the compressor due to over-wetting of the sucked refrigerant. In order to ensure that copper conditions are met when the heat pump load changes, pressure and temperature sensors may be provided on the discharge line near the compressor. The sensing signal can be fed into the microprocessor containing refrigerant thermodynamic data so that the microprocessor can calculate the overheat of the discharged steam. The superheat value controls the degree of opening of the electric shoe expansion valve (EEV) and thereby varies the flow of refrigerant into the evaporator. If the evaporator load is reduced, the discharge superheat (discharge superheat) decreases with the risk of liquid aluminium in the compressor at the end of compression. The EEV controlled by the pressure and temperature sensors may reduce the refrigerant flow and thereby increase the discharge superheat to a preset value. This is a method of controlling the injection of liquid aluminum into the compressor.

In another embodiment, a thermal expansion valve (TXV) and a gas storage sensor on the discharge line may be used to control the flow of refrigerant into the evaporator and thereby ensure that the discharge temperature does not drop below a preset value.

Operating the heat pump apparatus with the flooded evaporator and the very wide glide composition provides other advantages over conventional operations whereby the refrigerant is completely evaporated and superheated. First, incomplete evaporation reduces temperature slip so that it can more closely approximate the desired temperature profile for a particular application. Second, the entire internal surface area of the evaporator is used for evaporation, which is a highly efficient heat transfer mode compared to vapor. Third, allowing the liquid aluminum to leave the evaporator enables the composition to include a low volatility nonflammable HFO component in order to inhibit the flammability of flammable components such as R32, particularly R1234yf and R1234ze (E), thereby facilitating the reduction or elimination of the flammability of the entire composition.

It is believed that non-azeotropic blends with wide and extremely wide inherent slip will not function in heat pump equipment. However, the present inventors have unexpectedly found that the wide or very wide glide refrigerant of the present application can be used in heat pump devices. Actual temperature glide of about 4 to about 6K may be induced in conventional refrigeration equipment using typical evaporator pressure drops of about 0.3 to about 0.7 bar. Evaporator slippage is thus a feature of existing refrigeration equipment using conventional HFC refrigerants, although simple modeling assumes that evaporation occurs at constant pressure and temperature. The inherent slip of the blends of the present application can offset pressure induced slip such that the actual evaporator slip can be in the range of 1 to 4K, i.e., it can be smaller than existing equipment. Preferably, the actual slip should be approximately equal to the slip of the cooled heat source.

In prior art designs, the pressure drop between the condenser and the evaporator occurs primarily across the expansion device. Minimizing the pressure drop across the heat exchanger. However, the inventors have unexpectedly found that it can be advantageous to share the total pressure drop between the expansion device and the evaporator in the case of a blend slip that is wide and extremely wide. The greater the pressure drop across the evaporator, the less slip of copper is observed, since the pressure induced slip opposes the inherent refrigerant slip. But surprisingly, the energy efficiency and suction capacity are independent of the evaporator pressure drop.

The evaporator pressure drop can be varied by making one or more of the following modifications to the evaporator tube. In this specification, the term "tube" refers to a length of tube with or without a "wrap around" configuration.

1. Reduce the diameter of the "" pipe.

2. Increase the pipe length.

3. The surface roughness of the inner surface of the tube is increased.

Combining a wide slip blend with an appropriate evaporator may advantageously allow for selective slip to match the desired temperature profile of the aluminum stream used as the evaporator heat source.

The above-described means for varying the pressure drop across the evaporator may also increase the heat transfer usable thermal area, thereby improving energy efficiency.

In a typical system, refrigerant enters a condenser from a compressor in an overheated state. The vapor is then cooled until it reaches the copper dew point and condenses until it is completely converted to liquid aluminum at its bubble point. Heat is removed from the liquid aluminum refrigerant so that it exits in a subcooled state (e.g., 5K apart) in the condenser. The wide slip refrigerant blends claimed in this specification can also be subjected to the same sequence in the condenser. However, it has been found that it may be advantageous for the wide slip blend to leave the condenser at its bubble point or at a vapor quality greater than zero to minimize condenser temperature slip. The refrigerant then enters the higher pressure side of the IHX where condensation is achieved and then subcooling is achieved by transferring heat to a lower temperature, lower pressure stream in the suction stream.

If the actual temperature glide is too great for a particular application, a recirculating condenser design may be used in which a portion of the liquid aluminum refrigerant from the condenser outlet is pumped back to the condenser inlet where it mixes with the discharge aluminum from the compressor and thermodynamically reaches copper balance. This keeps the discharge aluminum from overheating and can cool the compressor by removing heat from the compressor head.

The liquid aluminum coolant may be pumped in a variety of ways including, but not limited to, a jet pump or an electric turbine pump powered by exhaust aluminum flow.

The amount of actual temperature slip reduction depends on the circulation ratio, the higher the ratio the less slip. This is particularly advantageous for load-connected heat pumps, where the temperature difference between the entering and exiting temperatures of the second refrigerant, from which heat is removed, is less than the actual slip of a single pass condenser (i.e., a condenser with zero recirculation).

The refrigerant blends disclosed in this specification may have a combination of properties such as: non-flammability and heat capacity, extremely low GWP, compatibility with building materials (steel, copper aluminum alloys, polymeric seals) and polyol ester (POE) lubricants commonly used in the refrigeration and HVAC industries, which are comparable or superior to current commercial refrigerants without a close match to the thermodynamic properties of such refrigerants. By employing techniques particularly suited to the novel blends disclosed herein, the performance of specific applications using existing refrigerants can be optimized. The use of conventional design constraints associated with current commercial refrigerants may no longer apply. Importantly, the present invention can employ appropriate techniques to overcome the disadvantages of low GWP wide slip blends as considered from conventional evaluation of low or zero slip refrigerants.

The maximum operating pressure for a given design must not be exceeded for safety reasons. However, higher operating pressures may be considered if advantageous when designing new equipment from the blends claimed in this specification. For example, the blend may provide a higher capacity and thus require a relatively smaller compressor to be used. In this specification, the selection of a new blend may be unrestricted by what was previously considered necessary to match the accepted maximum operating pressure of the current commercial refrigerant.

The present invention imparts several advantages. The GWP of the refrigerant composition may be less than 400 and more preferably less than 150 and most preferably less than 10. Efficiency and capacity performance may be at least equal to the level achieved when using units operating with active commercial refrigerants. Discharge temperatures of less than 100 c can be achieved. The maximum operating pressure may be similar to the maximum operating pressure of a unit operating with an active commercial refrigerant. Whereby existing engineering components such as heat exchangers can be employed. The composition may provide non-flammable properties to ASHRAE safety class A1. In a preferred embodiment, a single refrigerant blend may be used for refrigeration, air conditioning, and heat pump applications.

The blends which are the subject of the invention can be used in refrigeration equipment which is lubricated by means of an oxygen-containing oil, such as polyol esters (POE) or polyalkylene glycols (PAGs), or by means of a mixture of such oils with up to 50% of a hydrocarbon lubricant, such as mineral oil, alkylbenzene or polyalphaolefin. It will be appreciated by those skilled in the art that the compressor lubricant in a heat pump system must match the refrigerant characteristics. The higher solubility of some HFOs in POE may result in the need for higher viscosity grades of these lubricants for use with the refrigerant blends of the present invention. This is particularly important for the lower volatility HFO that is the essential component in the blends of the present invention. Alternatively or additionally, lubricants with higher ratios of alkyl groups to ester groups may be preferred for reducing HFO solubility. This can be achieved by using POE with higher alkyl/ester ratio or by mixing separate hydrocarbons and POE lubricants.

Detailed Description

The invention is further described by way of example but not in any limiting sense.

Example 1

A comparison calculation was made for R410A used in the exemplary split air conditioning system shown in fig. 1, which system comprises: a hermetic compressor 2 driven by an electric motor 1, both components being enclosed in a pressure shell aluminum 12; an air cooled condenser 3, an electric shoe expansion valve 4, an air heating type evaporator 5 and a liquid storage 6. The exit temperature of the liquid aluminum refrigerant of the condenser is 40 ℃ and 5K supercooling is carried out. The vapor leaving temperature of the evaporator was 12℃and 5K was superheated. The unit is controlled by a microprocessor 8 which receives temperature values of the refrigerant leaving the evaporator from the temperature sensor 7 via data line 11 and from the room thermostat 13 via data line 14. 8 control the system in response to the input data to maintain the room temperature at the desired level, which is achieved by adjusting 4 via signal line 10 and adjusting the speed to 1 via signal line 9 and thereby the compressor capacity.

Key parameter values that exhibit refrigerant effectiveness are shown in table 1.

Example 2

A comparison calculation was performed for R404A used in a typical freezer also shown in fig. 1, which freezer comprises: a hermetic compressor 2 driven by an electric motor 1, both components being enclosed in a pressure shell aluminum 12; an air cooled condenser 3, an electric shoe expansion valve 4, an air heating type evaporator 5 and a liquid storage 6. The outlet temperature of the liquid aluminum refrigerant of the condenser is 30 ℃ and 5K supercooling is carried out. The vapor outlet temperature of the evaporator was-30 ℃,5K superheat. The unit is controlled by a microprocessor 8 which receives temperature values of the refrigerant leaving the evaporator from a temperature sensor 7 via a data line 10 and from a thermostat 13 located inside the freezer via a data line 14. 8 controls the system in response to the input data to maintain the freezer in the range of-18 ℃ to-23 ℃, by adjusting 4 via signal line 10 and adjusting the speed to 1 and thereby the compressor capacity via signal line 9.

Key parameter values that exhibit refrigerant effectiveness are shown in table 2.

Example 3

The calculation was performed for a non-flammable blend with GWP below 400 in a split air conditioning system (as shown in fig. 2) comprising a reservoir 14, a hermetic compressor 1, a condenser 4, an internal heat exchanger 5 to transfer heat from a higher temperature, higher pressure refrigerant stream to a lower temperature, lower pressure refrigerant stream, an electric shoe expansion valve 6, and an evaporator 10. The flow of refrigerant in the circuit is controlled by pressure and temperature sensors in the discharge line immediately after the compressor. The compressor is driven by a variable speed electric motor 12 and cooled by removing heat using a heat pipe 13. The unit is controlled by a microprocessor 9 which has been programmed for the thermodynamic properties of the refrigerant. The microprocessor receives input data from the temperature sensor 2 via data line 8 and from the pressure sensor 3 via data line 7, which sensors are located close to the discharge line of the compressor. The microprocessor transmits an output signal via signal line 15 which varies the speed of the motor and an output signal via signal line 11 which varies the degree of opening of the expansion valve, so that the efficiency of the unit matches the desired room temperature. In particular, the microprocessor ensures that the superheat of the refrigerant entering the discharge line is at least 5K to avoid potentially damaging wet compression.

To achieve a proper comparison with R410A in example 1, the refrigerant temperature was 40 ℃ at the exit of the condenser; the temperature entering the evaporator is 7 ℃; the isentropic efficiency of the compressor is 0.7; and the electric motor efficiency was 0.9. Depressurization across the evaporator to provide an actual temperature slip of 11K.

Key parameter values that demonstrate the refrigerant performance of blends 1-12 are shown in tables 3a and 3 b.

Example 4

The calculation was performed for a non-flammable blend with GWP below 400 in a refrigeration system (as shown in fig. 3) comprising a liquid reservoir 14, a hermetic compressor 1, a condenser 4, an internal heat exchanger 5 transferring heat from a higher temperature, higher pressure refrigerant stream to a lower temperature, lower pressure refrigerant stream, an electro-shoe expansion valve 6, and an evaporator 10. The flow of refrigerant in the circuit is controlled by pressure and temperature sensors in the discharge line immediately after the compressor. The compressor is driven by a variable speed electric motor 12 and cooled by using a syringe pump or liquid aluminum turbo pump 16 to draw liquid aluminum refrigerant from the liquid aluminum line just before the expansion valve 6 and pump the liquid aluminum refrigerant into heat exchange relationship 13 in contact with the compressor head. The unit is controlled by a microprocessor 9 which has been programmed for the thermodynamic properties of the refrigerant. The microprocessor receives input data from the temperature sensor 2 via data line 8 and from the pressure sensor 3 via data line 7, which sensors are located close to the discharge line of the compressor. The microprocessor transmits an output signal via signal line 15 which varies the speed of the motor and an output signal via signal line 11 which varies the degree of opening of the expansion valve, so that the efficiency of the unit matches the desired room temperature. In particular, the microprocessor ensures that the superheat of the refrigerant entering the discharge line is at least 5K to avoid potentially damaging wet compression.

To achieve a proper comparison with R404A in example 2, the refrigerant temperature was 30 ℃ at the exit of the condenser; the temperature entering the evaporator is-35 ℃; the isentropic efficiency of the compressor is 0.7; and the electric motor efficiency was 0.9. A pressure drop was applied across the evaporator to provide an actual temperature slip of 5K.

Key parameter values for blends 13 to 24 are shown in tables 4a and 4 b.

Example 5

For the separated air conditioning system (figure 4) composed of 5% R1224yd (Z) and 69% CO ₂ And 26% R1234ze (E) having a GWP of 2, the system comprising a reservoir 13; a dual-stage integrated hermetic compressor comprising a variable speed electric motor 4, a first stage 1 of lower pressure and a second stage 2 of higher pressure; a condenser 5; an internal heat exchanger (IHX) 6 for transferring heat from a higher temperature, higher pressure refrigerant stream to a lower temperature, lower pressure refrigerant stream; an electric shoe expansion valve 7 and an evaporator 8. The flow of refrigerant in the circuit is controlled by means of a pressure sensor 10 and a temperature sensor 11 in the suction line immediately after the IHX 6.

The gas aluminum exiting the first compression stage passes through an external heat exchanger, referred to as intercooler 3, where it is cooled by ambient air and then enters the gas aluminum volume within the compressor shell aluminum surrounding the electric motor and the 2-stage compressor. The vapor aluminum cools the motor and then enters the suction inlet of the second compression section where it is further compressed and then discharged into the condenser.

The unit is controlled by a microprocessor 9 which has been programmed for the thermodynamic properties of the refrigerant. The microprocessor receives input data from the temperature sensor 11, the pressure sensor 10, and the temperature sensor 14 measuring room temperature. The microprocessor transmits an output signal via signal line 15 that varies the speed of the motor and an output signal via signal line 12 that varies the degree of opening of the expansion valve, thereby optimizing the performance of the unit and matching the desired room temperature. In particular, the microprocessor ensures that the superheat of the refrigerant entering the compressor is at least 2K and preferably 5K to avoid potentially damaging wet compression.

To achieve a proper comparison with R410A in example 1, the refrigerant leaving the condenser is at 40 ℃; the temperature entering the evaporator is 7 ℃; the isentropic efficiency of the compressor is 0.7; and the electric motor efficiency was 0.9. A pressure drop was applied across the evaporator to provide an actual temperature slip of 11K.

Key parameter values that demonstrate refrigerant performance of blends consisting of 5% r 12240 yd (Z), 69% CO are shown in table 5 ₂ And 26% R1234ze (E). This blend is superior to R410A when used in air conditioning because it not only has a GWP of only 2 in combination with 107808kJ/kg (R410A: 5832 kJ/kg) of inhaled aluminum volume capacity, but also has similar energy efficiency. Blend is superior to CO ₂ Because it is at about 60 bar (CO ₂ : typically 130 bar) to reduce vapor back leakage into the compressor and to achieve subcritical cycle operation, thereby allowing efficient transfer of condensation heat to the environment.

Example 6

The calculation was performed for a non-flammable blend 26 in a split air conditioning system (as shown in fig. 4) operated under conditions similar to example 5, which blend was composed of 10% R1224yd (Z), 67% CO ₂ And 23% R1234yf and has a GWP of 2. Key parameter values that exhibit refrigerant effectiveness are shown in table 5. This blend is superior to R410A when used in air conditioning because it not only has a GWP of only 2 in combination with 11156kJ/kg (R410A: 5832 kJ/kg) of inhaled aluminum volume capacity, but also has similar energy efficiency. Blend is superior to CO ₂ Because it is at about 60 bar (CO ₂ : typically 130 bar) to reduce vapor back leakage into the compressor and to achieve subcritical cycle operation, thereby allowing efficient transfer of condensation heat to the environment.

Example 7

The calculation was performed for a non-combustible blend 27 in an air conditioning system (fig. 5) of an electric vehicle, consisting of 8% R1224yd (Z), 70% CO ₂ And 22% R1234ze (E) and hasSome GWP is 2, the system comprising a single-stage hermetic compressor driven by a variable speed electric motor 2; a condenser 3; an internal heat exchanger (IHX) 4 for transferring heat from a higher temperature, higher pressure refrigerant stream to a lower temperature, lower pressure refrigerant stream; an electric shoe expansion valve 5; an evaporator 6; a reservoir 13. The refrigerant flow in the circuit comprises a pressure sensor 7 in the suction line immediately after IHX 4 and a temperature sensor 8.

The unit is controlled by a microprocessor 9 which has been programmed for the thermodynamic properties of the refrigerant. The microprocessor receives input data from the temperature sensor 8 via data line 10, from the pressure sensor 7 via data line 11, and from the temperature sensor 16 measuring the temperature of the vehicle cabin via data line 15. The microprocessor transmits an output signal via signal line 14 that varies the motor speed and an output signal via signal line 12 that varies the degree of expansion valve opening, thereby optimizing the performance of the unit and matching the desired cabin temperature. In particular, the microprocessor ensures that the superheat of the refrigerant entering the compressor is at least 2K and preferably 5K to avoid potentially damaging wet compression.

Key parameter values that demonstrate refrigerant performance of blends consisting of 8% r 12240 yd (Z), 70% CO are shown in table 6 ₂ And 22% R1234ze (E). This blend (nonflammable, and GWP 2) is superior to R134a (nonflammable, but with high GWP 1300) and its substitute R1234yf (very low GWP (2), but flammable) when used in vehicular air conditioning. It also benefits from much higher suction specific aluminum volume capacities than these refrigerants. Blends are also superior to CO ₂ Because it is at about 66 bar (CO ₂ :130 bar) to reduce vapor back leakage into the compressor and to achieve subcritical cycle operation, thereby allowing efficient transfer of condensation heat to the environment.

Table 7 also provides performance data for blend 28 in an automotive air conditioning system.

Example 8

The performance of blends 29 to 37 (tables 7a and 7 b) containing HFC152a in the cryogenic refrigeration unit described in example 4 was calculated. The results are shown in table 7.

Example 9

The performance of blends 38 to 42 retrofitted for HFC32 in existing split air conditioners was calculated and compared to HFC32 (43 in table 8 b). The results are shown in tables 8a and 8 b. These blends provide acceptable energy efficiency and intake cooling capacity compared to HFC32, and GWP is less than half that of HFC32, thereby reducing the direct impact of split air conditioners on global warming.

Example 10

The efficacy of blends 44 through 45 (table 9) in a freezer unit similar to that described in example 4 was calculated. The results shown in table 9 demonstrate that good suction cooling capacity and efficiency are obtained. The blend GWP is less than 150, a value that some governments specify as an upper regulatory limit in order to force high GWP refrigerants (such as R404A and R507A) to be phased out.

Example 11

The efficacy of blends 48 through 51 (table 10) in a split air conditioning unit similar to that described in example 3 was calculated. The results shown in table 10 demonstrate that good suction cooling capacity and efficiency are obtained, which is advantageous over the existing refrigerants R410A and HFC32 currently used in this application. The blend GWP is less than 150, a value that some governments specify as an upper regulatory limit in order to force high GWP refrigerants (such as R410A and HFC 32) to be phased out.

TABLE 1

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TABLE 2

TABLE 3a

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TABLE 3b

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TABLE 4a

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TABLE 4b

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TABLE 5

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TABLE 6

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TABLE 7a

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TABLE 7b

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TABLE 8a

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TABLE 8b

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TABLE 9

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Table 10

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Claims

1. A refrigerant consisting of or consisting essentially of:

a) A nonflammable, highly volatile component consisting of carbon dioxide, and

d) An optional component selected from the group consisting of: HFC227ea, HFC152a, HFC32, and mixtures thereof.

2. The refrigerant of claim 1, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) An optional HFC selected from the group consisting of: HFC32, HFC227ea and R152a or mixtures thereof;

wherein the amount of the low volatile component is in the range of 5 wt% to 80 wt%;

wherein HFC227ea is present in an amount in the range of 1 wt% to 12.4 wt%;

wherein HFC152ea is present in an amount in the range of 2 to 10 weight percent; a kind of electronic device with high-pressure air-conditioning system

3. The refrigerant of claim 2, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) And an HFC selected from the group consisting of: HFC32, HFC227ea, and mixtures thereof;

wherein HFC227ea is present in an amount in the range of 1 wt% to 12.4 wt%;

4. The refrigerant of claim 3, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) An HFC selected from the group consisting of: HFC32, HFC152a and HFC227ea and mixtures thereof;

wherein HFC227ea is present in an amount in the range of 4.7 wt% to 12.4 wt%;

wherein HFC152ea is present in an amount in the range of 3 to 8 weight percent; a kind of electronic device with high-pressure air-conditioning system

5. The refrigerant of claim 3, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) And an HFC selected from the group consisting of: HFC32, HFC152a, HFC227ea, and mixtures thereof;

wherein the HFC227ea is present in an amount in the range of 1 wt% to 4.7 wt%;

wherein HFC152ea is present in an amount in the range of 3 to 5 weight percent; a kind of electronic device with high-pressure air-conditioning system

6. The refrigerant of claim 5, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

wherein the amount of HFC32 is in the range of 2 weight percent to 22 weight percent; a kind of electronic device with high-pressure air-conditioning system

7. The refrigerant of claim 6, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

wherein the amount of HFC32 is in the range of 10 weight percent to 21.5 weight percent; a kind of electronic device with high-pressure air-conditioning system

8. The refrigerant of claim 5, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

wherein the amount of HFC32 is in the range of 15 weight percent to 21.5 weight percent; a kind of electronic device with high-pressure air-conditioning system

9. The refrigerant of claim 5, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC227ea；

wherein the amount of HFC227ea is in the range of 2 wt% to 4.7 wt%; a kind of electronic device with high-pressure air-conditioning system

10. The refrigerant of claim 2, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

Wherein the amount of the high volatile component is in the range of 5 wt% to 90 wt%;

wherein the amount of the low volatile component is in the range of 2 wt% to 40 wt%;

wherein the amount of the medium volatile component is in the range of 15 wt% to 60 wt%; a kind of electronic device with high-pressure air-conditioning system

11. The refrigerant of claim 10, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

Wherein the amount of the high volatile component is in the range of 5 wt% to 80 wt%;

12. The refrigerant of claim 11, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

c) An optional medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO1225ye (Z), HFO1243zf, and mixtures thereof; a kind of electronic device with high-pressure air-conditioning system

Wherein the amount of the high volatile component is in the range of 50 wt% to 75 wt%;

wherein the amount of the low volatile component is in the range of 2 wt% to 25 wt%;

Wherein the amount of the medium volatile component is in the range of 15 wt% to 35 wt%; a kind of electronic device with high-pressure air-conditioning system

13. The refrigerant of claim 12, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

c) An optional medium volatile component selected from the group consisting of: HFO1234yf, HFO1234ze (E), HFO1225ye (Z), HFO1243zf, and mixtures thereof;

wherein the amount of the high volatile component is in the range of 60 wt% to 75 wt%;

wherein the amount of the low volatile component is in the range of 2 wt% to 20 wt%;

wherein the amount of the medium volatile component is in the range of 15 wt% to 30 wt%; a kind of electronic device with high-pressure air-conditioning system

14. The refrigerant of claim 2, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

15. The refrigerant of claim 14, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

16. The refrigerant of claim 15, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

17. The refrigerant of claim 16, consisting of or consisting essentially of:

a) Incombustible high volatile component CO ₂ ；

18. The refrigerant of claim 4, which is used in new equipment and retrofitted in existing equipment, the refrigerant consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d)HFC32；

wherein the amounts of the ingredients are selected from the ranges to a total of 100 wt.%; a kind of electronic device with high-pressure air-conditioning system

Wherein the blend has a bubble point vapor pressure of no more than 30 bar absolute at 40 ℃.

19. The refrigerant of claim 3, consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) HFC32, HFC227ea or mixtures thereof,

wherein the HFC227ea is present in an amount in the range of 2 wt% to 4.5 wt%;

wherein the amounts of these ingredients are selected from the ranges up to 100% by weight total, and

wherein the blend has a bubble point vapor pressure at 35 ℃ of no more than 30 bar absolute.

20. A refrigerant consisting of or consisting essentially of:

a) Incombustible high volatile components consisting of CO ₂ Composition;

d) HFC32, HFC227ea or mixtures thereof,

wherein the HFC227ea is present in an amount in the range of 2 wt% to 5 wt%; wherein the amounts of the ingredients are selected from the ranges to a total of 100 wt.%; a kind of electronic device with high-pressure air-conditioning system