RO107281B1 - Corrosion inhibitor - Google Patents

Abstract

The invention relates to a corrosion, for corrosion protection a installations where there are environments with relative content high salt, especially sodium chloride, such as would be, for example, in the oil extraction industry. The corrosion inhibitor consists of one a mixture of 20-60% by weight linear-alkyl-O- 107281 Bl sodium or ammonium benzenesulphonate, having linear-alkyl chain of 16 to 30 carbon atoms, 5% .10% by weight of naphthenic acids or fatty acids, with a molecular weight of 240 ... 280 and / or 30% .70% by weight amides of naphthenic acids or fatty acids.

Description

The invention relates to a corrosion inhibitor, for the protection of installations, in which liquid media with a high content of salts are found, in particular sodium chloride, such as, for example, in the oil extraction industry.

Corrosion inhibitors are known, which are made up of an aliphatic amine with a diffusive structure, of colloidal type, dispersible in water. (S.Socol et al. Anti-corrosion protection in the oil industry).

The disadvantage of these inhibitors is that they require high consumption, to ensure protection against corrosion and are toxic.

The technical problem solved by the invention consists in the formation of a synergistic mixture, comprising sodium or ammonium linear alkylbenzenesulfonate, naphthenic acids or fatty acids and / or amides of naphthenic acids or fatty acids.

The inhibitor according to the invention removes the disadvantages shown above, in that it consists of a mixture of 20, 60% by weight linear sodium or ammonium alkylbenzenesulfonate, having a linear alkyl chain of 16 ... 30 carbon atoms, 5 ... 10% by weight naphthenic acids, or fatty acids, with a molecular weight of 240 ... 280 and / or 30 ... 70% by weight amides of fatty acids or naphthenic acids.

The corrosion inhibitor according to the invention has the following advantages:

- is effective in salty environments and / or in the presence of crude oil and / or in the presence of CO2 and / or H2S;

- is effective in relatively small doses (1 ... 10 ppm);

- it is neither toxic nor inflammable.

Following are two examples of embodiments of the inhibitor according to the invention.

The inhibitor according to the invention consists of a mixture of 20 ... 60% by weight linear sodium or ammonium alkylbenzenesulfonate, having a linear alkyl chain of 16 ... 30 carbon atoms,

5 ... 10% by weight naphthenic acids or fatty acids with molecular weight of

240 .. .280, and / or 30 ... 70% by weight amide of naphthenic acids or of fatty acids. The synergistic mixture, thus obtained, is dissolved in water, alcohols or other suitable solvents and is introduced, for example, into a pipeline for the transport of saltwater, geothermal water, seawater or crude oil with or without impurities, in quantities of

1 .. .10 ppm or used for the protection of the bottom equipment, for the extraction of crude oil, in the presence of carbon dioxide and / or hydrogen sulphide

Example 1. In a reaction vessel, with a capacity of up to about 3 rn, with an anchor shaker and the heating and cooling jacket, 200 kg naphthenic acids with acidity index are introduced under stirring.

180 .. .200 mg KOH / g and 60 kg ethylenediamine 98% concentration. The mixture is heated slowly for 2 hours to a temperature of 120 ... 130 ° C and kept for 12 hours, after which it is allowed to cool to a temperature of

25 .. .30 ° C and 260 kg linear sodium alkylbenzenesulfonate are added to the linear alkyl chain with 16 ... 25 carbon atoms and stirred for one hour. The product thus obtained is mixed with water, in a ratio of 1: 2, a form in which it can be used in operations to combat corrosion of pipes for the transport of groundwater, marine waters or other chlorine-containing media.

Example 2. In a reaction vessel, identical to that of Example 1, 200 kg naphthenic acids with an acidity index of 140-160 mg KOH / g and 40 kgetylenediamine of 98% concentration are introduced under stirring. The mixture is heated to a temperature of 180 ... 200 ° C for 3 hours and kept for 24 hours, after which it is cooled down to a temperature of

25 ... 30 ° C and 240 kg linear sodium alkylbenzenesulfonate are added to the linear alkyl chain with 20 ... 30 carbon atoms and stirred for one hour. The product thus obtained is dissolved in crude oil or a fraction of crude oil, in a ratio of 1: 1, and is used to protect against corrosion of pipes, for the transport of crude crude oil or oil-water mixture in any proportion. The product can also be used to protect bottom equipment for the extraction of crude oil or other fluids containing carbon dioxide and / or hydrogen sulphide. The inhibitor is inserted into the annular space between an operating bore column and an extraction pipe gasket, unless a packer is mounted directly in the extraction pipe gasket or by injection into the pore or cracked environment.

Claims (3)

Claim Corrosion inhibitor, characterized 5 in that it is made up of a mixture of 20 ... 60% by weight linear sodium alkylbenzenesulphonate or ammonium, having the linear alkyl chloride having 16 ... 30 carbon atoms, 5 ... 10% by weight acids. 10 naphthenics or fatty acids with a molecular weight of 240 ... 280 and / or 30 ... 70% by weight amide of naphthenic acids or fatty acids. Staple 15