RU2745618C1 - Method for increasing stability against oxidation of transformer oil by introducing petroleum sulfides - Google Patents

Abstract

FIELD: oil production.

SUBSTANCE: invention describes a method for increasing the stability against oxidation of transformer oil by introducing petroleum sulfides, which consists in adding an antioxidant additive to the oil at the production stage, the antioxidant additive being petroleum sulfur-organic compounds of the general formula C_nH_2n-5S containing aromatic rings at a concentration of 0.5%.

EFFECT: increasing the stability against oxidation of any petroleum transformer oils, regardless of the method of their purification, as well as reducing the cost of oil production.

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Description

The present invention relates to the field of energy, in particular the production of transformer oil used in oil-filled electrical equipment.

Application: production of transformer oils.

The prototype is a method of slowing down oil oxidation, based on the addition of an antioxidant additive ionol (C ₁₅ H ₂₄ O) to transformer oils, which breaks oxidative chains and acts as a deactivator of free radicals and as a substance that interacts with hydroperoxides to form inactive products. [Lipstein R.A. Transformer oil / R.A. Lipstein, M.I.Shakhnovich. 3rd ed., Rev. and add. M .: Energoizdat, 1983. - P.76]. At present, ionol is widely used in power engineering as an antioxidant additive for transformer oils of various brands. However, oils containing no more than 0.4-0.6% sulfur are good in terms of susceptibility to additives.

Disadvantages of the method: the susceptibility of oils to the action of the antioxidant additive ionol is determined by the depth of purification of the distillate, i.e. depends on the composition of the original oil.

An analogue is a method of slowing down the oxidation of transformer oil, based on adding to the transformer oils an antioxidant additive methyl phenyl sulfide (C ₇ H ₈ S) at a concentration of 0.53%, containing sulfur with a free pair of electrons that capture free radicals of the oil [Patent for invention No. 2653541 from 05/11/2018].

Disadvantages of the method: the use of methylphenyl sulfide, obtained synthetically, increases the cost of producing transformer oil.

The objective of the invention is to develop a method for increasing the stability against oxidation of transformer oil by introducing petroleum sulfides, which eliminates the disadvantages of the prototype and analogue.

The technical result is to increase the stability against oxidation of any petroleum transformer oils, regardless of the method of their purification, as well as to reduce the cost of oil production.

The technical result is achieved by the fact that in the method of increasing the stability against oxidation of transformer oil by the introduction of petroleum sulfides, which consists in the fact that at the stage of production an antioxidant additive is added to the oil, according to the present invention, the antioxidant additive is petroleum sulfur compounds with the general formula C _n H _{2n- 5} S at a concentration of 0.5%.

The method is carried out as follows: at the stage of production of transformer oil after the process of purification of the base product, petroleum sulfur compounds are introduced into it with the general formula C _n H _2n-5 S, at a concentration of 0.5%. The optimal concentration of 0.5% was determined experimentally [Influence of the additives of natural sulfur-organic compounds on thermal stability of oil fractions of arlan petroleum. To cite this article: LR Gainullina et al 2018 IOP Conf. Ser .: Mater. Sci. Eng. 412 012016].

To confirm the effectiveness of the proposed method, experiments were carried out comparing the performance indicators of antioxidant additives ionol, methylphenyl sulfide and petroleum sulfur compounds in selectively refined transformer oil. For this purpose, ionol, methyl phenyl sulfide, and petroleum sulfur compounds were added to the oil fractions after appropriate purification. For the obtained transformer oils, studies of stability against oxidation in an electric field were carried out at an operating temperature of operation in accordance with GOST 981-75, oxidation was carried out and the following indicators were measured: the amount of sediment, water-soluble acids, acid number. The experimental results are shown in Table 1 [Influence of the additives of natural sulfur-organic compounds on thermal stability of oil fractions of arlan petroleum. To cite this article: L R Gainullina et al 2018 IOP Conf. Ser .: Mater. Sci. Eng. 412 012016].

Table 1 Indicators of the effectiveness of antioxidant additives

Transformer oil + additive Water-soluble acids, mg KOH / g oil Sludge amount,% Acid number, mg KOH / g oil Selective cleaning GOST 10121-76 (ionol) 0.056 0.042 0.1 Selective cleaning (no ionol) +
methylphenylsulfide 0.023 0.0031 0.054 Selective cleaning (no ionol) +
petroleum sulfur compounds of the general formula C _n H _2n-5 S 0.003 0.005 0.01

Petroleum sulfur compounds of the general formula C _n H _2n-5 S are sulfides containing aromatic rings. Also, petroleum sulfur compounds with the general formula C _n H _2n-5 S, in contrast to ionol, are effective for transformer oils of any purification methods; Unlike methyl phenyl sulfide, petroleum sulfides are not synthesized, they are already included in the oil fraction, which makes the oil production process cheaper. Thus, selectively refined transformer oils with petroleum sulfur compounds of the general formula C _n H _2n-5 S as an antioxidant additive in all of the above indicators are more effective than the same oils, but with ionol or methyl phenyl sulfide.

Claims (2)

1 Claims A method of increasing the stability against oxidation of transformer oil by introducing petroleum sulfides, which consists in adding an antioxidant additive to the oil at the production stage, characterized in that the antioxidant additive is petroleum sulfur-organic compounds of the general formula C _n H _2n-5 S containing aromatic rings, at a concentration of 0.5%.