OA18287A - Non-azeotropic fluid mixture for air conditioning devices - Google Patents

Abstract

A non-azeotropic fluid mixture for air conditioning apparatus characterised because the mixture comprises the following refrigerant fluids (gases) in given proportions: - 2- Methylpropane (Isobutane) CH (CH3)3 (R-10 600a), Pentafluoroethane (R-125), - Tetrafluoroethane (R-134a) - Difluoromethane (R-32). The composition of the mixture contains at least one polymerisation inhibitor agent (hydroquinone, benzotriazole, dimethyl-t-butylphenol).

Description

NON-AZEOTROPIC FLUID MIXTURE FOR AIR CONDITIONING DEVICES.

DESCRIPTION

OBJECT OF THE INVENTION

The invention promoted refers to a nonazeotropic fluid mixture for air conditioning 10 devices, a fluid mixture used in such devices as the means for cooling them.

FIELD OF THE INVENTION

The field of the invention is that of the chemical industry, and more specifically the gas production industry and the industry for the manufacture of air conditioning devices.

BACKGROUND OF THE INVENTION

There are many precedents in the use of gases for various purposes.

There are also some precedents in connection with fluid mixture for the air conditioning industry.

Examples of these precedents may be reflected in the patent document.

REFRIGERANT COMPOSITION.

Publication number: Also published as:

ES2354043T3

EP1765953Al

EP1765953B1

W02005083028 Al (09.03.2011) (28.03.2007) (06.10.2010) (09.09.2005)

Applicant: RPL HOLDINGS LIMITED (GB) CIP: C09K5/04 (2006.01)

Abstract: A réfrigérant composition consisting in weight essentially of: 53.2 R134a at 39% R125 45 - 55% 0.6 isopentane at 1% 0.6 butane at 3% 0.6 isobutane at 2%.

It does indeed offer substantial différences from the composition of the invention proposed.

COMPOSITION OF A WORKING FLUID FOR A

REFRIGERATING MACHINE.

Publication number: ES2082148

Also published as: EP0475751 EP0475751

T3 (16.03.1996)

Al (18.03.1992)

Bl ¢06.12.1995)

Applicant: KAO

CIP: C09K5/00 (2006.01)

CORPORATION (JP)

This invention describes a composition for the operating fluid of a refrigerating machine comprising: a hydrofluorocarbon and an ester formed between a neopentilpoliol and a branched, saturated aliphatic monocarboxylic acid, with carbon number from 7-9. The composition of the working fluid in this invention is excellent in terms of its compatibility, lubrication, thermal stability and insulating properties.

The characteristics of this invention are however new and are not ali anticipated in unified form, for the reasons set out below.

The field of this invention refers to use of the mixture in the invention as réfrigérant in air conditioning Systems both for the production of cold and as heat pump.

That mixture is applied to single cycle refrigerating circuits with a steam compression system.

The mixture performance has been evaluated according to the refrigerating load, discharge température, the power used by the compressor and the COP, EER, SCOP and SEER.

The composition in the invention has a cyclic yield which is enhanced in comparison with conventional réfrigérants available, such as R-410A or R-407C, when used both to produce cold and in a heat pump.

After multiple trials, the réfrigérant mixture which is the subject of this invention was placed in the highest energy classification, A+++.

The current trend in the field of réfrigérants 10 is to create less or zéro environmental impact, so the élimination of chlorine from its composition yields a zéro value for ODP (Ozone Déplétion Potential), while working for maximum réduction of GWP (Global Warning Potential), the most noble being 13 natural réfrigérants (NH3, Co2) or hydrocarbons (HC) , and finally HFC of low GWP, such as the mixture in this invention, its ODP index = 0 and a very low GWP.

There is not at this time, as authoritative 20 value on the market, a composition such as that in this invention which is so energy-efficient compared with other existing mixtures, producing energy savings of between 40% and 60%, contributing indirectly to a réduction of CO2 in electricity 25 production.

A further factor to be considered is that existing less pollutant réfrigérants hâve relatively high toxicity and inflammability values, making them 30 less safe to handle.

The mixture proposed in this invention is both thermally and chemically very stable under severe conditions of both température and pressure.

The AEL (Allowable Exposure Limit) value is 1000 ppm (8 hours TWA).

Thus it is classified among High Security 40 réfrigérants.

The inventor is unaware of any forerunner which incorporâtes the provisions of this invention nor the benefits bestowed by such provisions.

DESCRIPTION OF THE INVENTION

The proposed invention refers, as its title suggests, to a non-azeotropic fluid mixture for air conditioning apparatus.

To define the major parameters of this invention, exhaustive research was carried out on the ratios of the proportion of the mixture, resulting in physical-chemical and thermodynamic properties included in the following technical spécifications.

More specifically, the invention considers the mixture in terms of different proportions of the following réfrigérant fluids (gases):

2-Methylpropane

600a), (Isobutane) CH(CH3)3 (RPentafluoroethane (R-125) ,

Tetrafluoroethane (R-134a)

Difluoromethane (R-32),

The mixture*s composition includes at least one polymérisation inhibiting agent (hydroquinone, benzotriazole, dimethyl-t-butylphenol, etc.).

That is ail for use in air conditioning and refrigerating equipment, both domestically and industrially and in automobiles, with its cold and heat applications.

PREFERENTIAL EMBODIMENT OF THE INVENTION

The invention proposed refers to a nonazeotropic fluid mixture for air conditioning devices, a fluid mixture employed in such apparatus 15 as a means to cool them.

The cyclic performance of the composition in the invention is enhanced compared with conventional réfrigérants available and, in synthesis, comprises 20 the following gases in the proportions indicated:

0.5-5% 2-Methylpropane {Isobutane) CH(CH3)3, commercially known as (R-600a), l%-10% Pentafluoroethane, commercially known as (R-125),

75%-95% Tetrafluoroethane, commercially known as (R-134a),

2%-20% Difluoromethane commercially known as (R-32), .- 0.03-3 parts of weight of polymerization inhibitor for every 100 parts of the previous mixture

The main polymerization inhibitor. agents are hydroquinone, benzotriazole or dimethyl-tbutylphenol .

The mixture obtained by these means is a compound, chemically stable non-azeotropic ternary mixture with good thermodynamic properties, low environmental impact and very low toxicity.

The mixture is classified as Al group L1 of High Security réfrigérants and with a température glide of 7.2°C.

Because it is not miscible with minerai oils, it must be used with polyester oils (POE).

i

To avoid fractionation, it must be loaded during the liquid phase.

The mixture toxicity is very low, even after exposure. The AEL value (Allowable Exposure Limit) is 1000 ppm. (8 hours TWA).

The following table shows a resuit of its

Physical Properties.

PFIYSICAL PROPERTIES
Molecular point	(g/mol)	93.4
Boiling température (at 1.013 bar)	CO	-30.8
Freezing point	ro	-102
Critical température	co	1003
Critical pressure	(abs bar)	41.09
Critical density	(kg/m3)	514
Liquid density (25*0	(kg/m3)	1180
Liquid density (-25*0	(kg/m3)	1307
Saturated va pour density	(kg/m3)	4.9
Vapour pressure (25*0	(bar abs)	73
Vapour pressure (-25*0	(bar abs)	2.4
Boiling point vaporisation heat	(kj/kg)	223
Spécifie liquid heat (25*0 (1.013 bar)	(kj/kg k)	1.48
Spécifie vapour beat (25*0 (1.013 bar)	(kj/kg k)	0.84
Thermal conductibility of the liquid (25*0	(W/mk)	0.085
Thermal conductibility of the vapour (1 atm.)	(W/mk)	0.0138
Liquid viscosity (25*0	(cP)	0.204
Surface pressure (25*0	(mN/m)	8.04
Solubility with water (25*C at 1.013 bar)	(wt%)	0.15
Réfrigérant volumétrie capacity (25*C)	(kg/m3)	1196.45
Inflammability limit in air at 1 atm.	(%vol)	none
Toxicity (AEL)	(ppm)	1000
PCA (GWP)		1263
ODP	-	0
sF.ER	A+++	1538

The mixture obtained by these means as réfrigérant fluid will be used in both domestic and industrial air conditioning equipment, and in 5 automobiles and also as réfrigération, and has an energy classification of A+++.

This is a mixture whose réfrigérant composition does not damage the ozone layer, has little global 10 warming effect, very low inf lammability, very low toxicity and which is very energy-efficient.

Having sufficiently described the nature of the invention and how to put it into practice, it must be 15 recorded that the foregoing spécifications, also shown in the attached drawings, may be modified in detail provided that this does not alter their fundamental principles established in the previous paragraphe and summarised in the following claims.

Claims (3)

1. - A non-azeotropic fluid mixture for air conditioning devices, a fluid mixture used in such devices as a means to refrigerate them, characterised because it comprises the following gases, in the proportions set out:

0.5%-5% 2-Methylpropane (Isobutane) CH(CH3)3, commercially known as (R-600a), l%-4,99% Pentafluoroethane, commercially known as (R-125), . - 91%-95% Tetrafluoroethane, commercially known as (R-134a),

2%-4,99% Difluoromethane, commercially known as (R32),

0.03-3 parts in weight of polymérisation inhibitor for each 100 parts of the previous mixture.

2. - A non-azeotropic fluid mixture for air conditioning devices, a mixture of fluids used in such devices to cool them, as set forth in Claim 1 and characterised because the polymérisation inhibitor agents are principally hydroquinone, benzotriazole or dimethyl-tbutylphenol.

3. - A non-azeotropic fluid mixture for air conditioning devices, a mixture of fluids used in such devices to cool them, as set forth in Claim 1 and characterised because the energy classification of the mixture obtained by these means as réfrigérant fluid is A+++.