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Paramétrages

Paramétrages

1. CA2625185 - FLUIDES DIELECTRIQUES A BASE D'HUILE VEGETALE DE FAIBLE VISCOSITE

Note: Texte fondé sur des processus automatiques de reconnaissance optique de caractères. Seule la version PDF a une valeur juridique
CLAIMS:
1. A dielectric fluid composition comprising: a vegetable oil of a high mono-unsaturated fatty acid content; and one or more fatty acid alkyl esters, each having a fatty acid moiety and an alkyl moiety, wherein the alkyl moiety of the fatty acid alkyl esters has 1 to 4 carbon atoms; and wherein the vegetable oil is in the range of 40%-60% v/v of the dielectric fluid composition and the a fatty acid alkyl ester is in the range of 40%60% v/v of the dielectric fluid composition.
2. The dielectric fluid composition according to claim 1, wherein the monounsaturated fatty acid content of the vegetable oil is > 60%.
3. The dielectric fluid composition according to claim 1 or claim 2, wherein mono-unsaturated fatty acid content of the vegetable oil is about 80%.
4. The dielectric fluid composition according to any one of the preceding claims, wherein the vegetable oil is selected from the group comprising: natural vegetable oil, synthetic vegetable oil, genetically modified vegetable oil, and mixtures thereof.
5. The dielectric fluid composition according to any one of the preceding claims, wherein the vegetable oil is selected from a group comprising: castor oil, coconut oil, corn oil, cottonseed oil, linseed oil, olive oil, palm oil, peanut oil, grapeseed oil, canola oil, safflower oil, sunflower oil, and soybean oil, high oleic variants thereof, and mixtures thereof.
6. The dielectric fluid composition according to any one of the preceding claims wherein the monounsaturated fatty acid is one or more of the group: obtusilic,
caproleic, lauroleic, linderic, myristoleic, physeteric, tsuzuic, palmitoleic,
petroselinic, oleic, vaccenic, gadoleic, gondoic, cetoleic, erucic, and nervonic acids.
7. The dielectric fluid composition according to any one of the preceding claims wherein the vegetable oil comprises a high oleic acid content.
8. The dielectric fluid composition according to claim 7, wherein the oleic acid content of the vegetable oil is > 60%.
9. The dielectric fluid composition according to claim 8, wherein the oleic acid content of the vegetable oil is about 80%.
10. The dielectric fluid composition according to any one of the preceding claims, wherein the vegetable oil is a high oleic sunflower oil (HOSO) with
oleic acid and < 3% linoleic acid.
11. The dielectric fluid composition according to any one of the preceding claims, wherein the alkyl moiety of the or each fatty acid alkyl ester has 1 to 2 carbon atoms.
12. The dielectric fluid composition according to any one of the preceding claims, wherein the fatty acid alkyl ester comprises one or more monounsaturated fatty acid esters.
13. The dielectric fluid composition according to any one of the preceding claims, wherein the fatty acid alkyl ester comprises one or more esters of one
or more monounsaturated fatty acids selected from the following group: obtusilic, caproleic, lauroleic, linderic, myristoleic, physeteric, tsuzuic, palmitoleic, petroselinic, oleic, vaccenic, gadoleic, gondoic, cetoleic, erucic, and nervonic acids.
14. The dielectric fluid composition according to any one of the preceding claims, wherein the fatty acid moieties of the fatty acid alkyl esters are substantially homologous with the monounsaturated fatty acid content of the vegetable oil of the dielectric fluid composition.
15. The dielectric fluid composition according to any one of the preceding claims, wherein above 60% of the fatty acid moieties of the fatty acid alkyl esters is derived from one or more mono-unsaturated fatty acids .
16. The dielectric fluid composition according to claim 15, wherein about 80% of the fatty acid moieties of the fatty acid alkyl esters is derived from one or more mono-unsaturated fatty acids.
17. The dielectric fluid composition according to any one of the preceding claims, wherein the fatty acid alkyl esters comprise fatty acid alkyl esters derived from the vegetable oil of the dielectric fluid composition.
18. The dielectric fluid composition according to any one of the preceding claims, wherein the dielectric fluid composition further comprises at least one additive, the or each additive being selected from a group comprising antioxidants, pour point depressants, corrosion inhibitors, anti-bacterials, viscosity modifiers.
19. The dielectric fluid composition according to claim 18, wherein the antioxidant additives comprise metal deactivators.
20. A dielectric fluid composition according to any one of the preceding claims wherein the viscosity of the dielectric solution is < 20 cSt at 40°C.
22. A transformer having a housing which accommodates a transformer core/coil assembly and a dielectric fluid composition surrounding said core/coil assembly, wherein the dielectric fluid composition is as defined in any one of
the preceding claims.
23. A method of lowering the viscosity of a vegetable oil-based dielectric fluid comprising a vegetable oil comprising a high mono-unsaturated fatty acid
content comprising blending the vegetable oil-based dielectric fluid with one or more fatty acid alkyl esters wherein the alkyl moiety of the fatty acid alkyl ester has 1 to 4 carbon atoms, and wherein the vegetable oil based dielectric fluid is blended with the fatty acid alkyl esters in a ratio of 40:60 - 60:40.
24. The method according to claim 23, wherein the volume of fatty acid alkyl esters blended with the vegetable oil-based dielectric fluid is sufficient to obtain a viscosity of < 20 cSt @40°C.
25. A viscosity modifier for vegetable oil-based dielectric fluids having a high mono-unsaturated fatty acid content, the viscosity modifier comprising one or more fatty acid alkyl esters, having an alkyl moiety and a fatty acid moiety, wherein the alkyl moiety has 1 to 4 carbon atoms.
26. The viscosity modifier according to claim 25, wherein the wherein the alkyl moiety of the fatty acid alky ester has 1 or 2 carbon atoms.
27. The viscosity modifier according to any one of claims 25 or 26, wherein the fatty acid moiety of the fatty acid alkyl ester is derived from one or more mono-unsaturated fatty acids,.
28. The viscosity modifier according to any one of claims 25 to 27, wherein the the mono-unsaturated fatty acids are selected from a group comprising:
obtusilic, caproleic, lauroleic, linderic, myristoleic, physeteric, tsuzuic, palmitoleic, petroselinic, oleic, vaccenic, gadoleic, gondoic, cetoleic, erucic, and nervonic;.
29. The viscosity modifier according to any one of claims 25 to 28, wherein above 60% of the fatty acid moieties of the fatty acid alkyl ester is derived from one or more mono-unsaturated fatty acids.
30. The viscosity modifier according to claim 29, wherein about 80% of the fatty acid moieties of the fatty acid alkyl ester is derived from one or more mono-unsaturated fatty acids.
31. The viscosity modifier according to any one of claims 25 to 30, wherein the fatty acid alkyl ester is derived from the vegetable oil from which the dielectric fluid is based.
32. A process for producing a dielectric fluid composition comprising the steps of: a) providing a first volume of vegetable oil and a second volume of vegetable oil, the vegetable oil being of a high mono-unsaturated fatty acid content; b) esterifying the first volume of vegetable oil with an alcohol containing 1 to 4 carbon atoms and forming a fatty acid alkyl ester; and c) blending the fatty acid alkyl ester with the second volume of vegetable oil in a ratio of 40:60 - 60:40.
33. The process according to claim 32, wherein the vegetable oil is selected from the group comprising natural vegetable oil, synthetic vegetable oil, genetically modified vegetable oil, and mixtures thereof.
34. The process according to claim 32 or claim 33, wherein the vegetable oil is selected from a group comprising castor oil, coconut oil, corn oil, cottonseed oil, linseed oil, olive oil, palm oil, peanut oil, grapeseed oil, canola oil, safflower oil, sunflower oil, and soybean oil, high oleic variants thereof, and mixtures
thereof.
35. The process according to any one of claims 32 to 34, wherein the monounsaturated fatty acid content of the vegetable oil is > 60%.
36. The process according to claim 35, wherein the mono-unsaturated fatty acid content of the vegetable oil is about 80%.
37. The process according to any one of claims 32 to 36, wherein the vegetable oil comprises a high oleic acid content.
38. The process according to any one of claims 32 to 37, wherein the oleic acid content of the vegetable oil is > 60%.
39. The process according to any one of claims 32 to 38, wherein the oleic acid content of the vegetable oil is about 80%.
40. The process according to any one of claims 32 to 39, wherein the vegetable oil is a high oleic sunflower oil (HOSO) with 80% oleic acid and <
linoleic acid.
41. The process according to any one of claims 32 to 40, wherein step b) of esterifying the first volume of vegetable oil is performed in the presence of
base catalyst.
42. The process according to claim 41, wherein the base catalyst is selected from a group comprising: sodium hydroxide, potassium hydroxide, sodium
alkoxides, potassium alkoxides, alkali metal alkoxylate catalysts selected from the group consisting of sodium methanolate, sodium ethanolate, sodium propanolate, sodium butanolate, potassium methanolate, potassium ethanolate, potassium propanolate, potassium butanolate and mixtures thereof, triethanolamine.
43. The process according to any one of claims 32 to 40, wherein step b) of esterifying the first volume of vegetable oil is performed in the presence of an acid catalyst.
44. The process according to claim 43, wherein the acid catalyst is an inorganic acid catalyst selected from the group consisting of sulfuric acid, phosphoric acid, hydrochloric acid, or mixtures thereof.
45. The process according to any one of claims 32 to 44, wherein the dielectric fluid composition is further blended with at least one additive, the or each additive being selected from a group comprising anti-oxidants, pour point
depressants, corrosion inhibitors, anti-bacterials, viscosity modifiers.
46. The process according to any one of claims 32 to 45, further comprising the step of depleting said composition of water and other conductive contaminants such as acid.
47. The process according to claim 46, wherein the step of depleting said composition comprises contacting the dielectric fluid composition with adsorption media.
48. The process according to claim 47, wherein the adsorption media to remove water is selected from a group comprising chemical desiccants such as silica gel or anhydrous magnesium sulphate, or molecular sieves.
49. The process according to claim 47, wherein the adsorption media to remove acid is selected from a group comprising diatomaceous earth, attapulgite, or Fuller's earth.
50. The process according to any one of claims 47 to 49, wherein the dielectric fluid composition is contacted with said adsorption media by eluting the dielectric fluid composition through a column of said adsorption media.
51. The process according to any one of claims 47 to 50, wherein the step of depleting the dielectric fluid composition of water and contaminants comprises
eluting the dielectric fluid composition through a first adsorption medium and
removing water, and then eluting the dielectric fluid composition through a second adsorption medium and removing acid.
53. The process according to any one of claims 32 to 45, further comprising the step of depleting the second volume of vegetable oil and the alkyl esters of water and other conductive contaminants such as acid, prior to blending the second volume of vegetable oil with the alkyl esters.
54. The process according to claim 53, wherein the second volume of vegetable oil and the alkyl esters are separately eluted through respective first adsorption media to remove water, and then separately eluted through respective second adsorption media to remove acid.
55. Use of a composition comprising: a vegetable oil of a high mono-unsaturated fatty acid content; and one or more fatty acid alkyl esters, each having a fatty acid moiety and an alkyl moiety, wherein the alkyl moiety of the fatty acid alkyl esters has 1 to 4 carbon atoms; and wherein the vegetable oil is in the range of 40%-60% v/v of the dielectric fluid composition and the a fatty acid alkyl ester is in the range of 40%60% v/v of the dielectric fluid composition
as a dielectric fluid.