CZ2012971A3 - Corrosion-preventive method of protection of crude-oil production - Google Patents

Abstract

The method of protecting equipment for extracting, transporting and storing oil consists in treating the mined, transported and stored media with metal corrosion inhibitors containing a film-forming fatty amine with an unsaturated fatty alcohol. 10 to 50 l of an aqueous octadecylamine emulsion containing 1 to 20 wt. % octadecylamine and 0.0001 to 0.1 wt. unsaturated alcohols, especially propargyl alcohol. In places still contaminated by water phase plus salt, in tons, with some delay, the equipment is further introduced into the cathode conditions by means of an industrial potentiostat and the sacrificial anode is situated in the aqueous environment.

Description

Method of anticorrosive protection of oil extraction equipment

Technical field

The invention relates to a process for the corrosion protection of an oil production plant.

BACKGROUND OF THE INVENTION

In oil extraction, transport and storage, the components of equipment used, such as probes, pumps, tanks and their components, equipment for pumping, mixing and other mechanical operations, are highly corrosive because they are in continuous contact with oil and its saturated vapors or a process gas such as carbon dioxide. Corrosion is then caused by the action of acidic components, such as carbon dioxide or sulfane, by the action of the water contained in the emulsified form in the oil and the inorganic substances dissolved therein (salts with a predominant chloride content). The corrosion effects of carbon dioxide occur throughout the area of contact with the device, while the corrosive effects of water where there is separation (lower points of the plant at a slow flow rate) or condensation from the vapor phase. In addition to the two components mentioned above - carbon dioxide, which is used to intensify extraction, and crude oil, which is a natural component of petroleum, crude oil also contains significant amounts of organic acid sulfur (mercaptans, sulphides, polysulphides, etc.). This complicated environment can be corrosive to the equipment even in the absence of water.

However, each oil reservoir contains water which, as a heavier liquid, is primarily in the lower and middle part of the reservoir. In the middle because oil contains polymer compounds such as maltens, asphaltenes, etc., which are heavy. During extraction, water is always part of the extraction medium and is thus in constant contact with the extraction probe and other parts of the extraction set. They are microscopic water particles up to occasional flooding of the probe. Since water always carries a lot of dissolved salts (even hazardous chlorides), this mixture is corrosive to the probe and its surrounding equipment.

i>.:.

Although various materials with sufficient corrosion resistance to the described substances (high-alloy steels) are available, for large parts of oil extraction, transport and storage facilities, they are largely not economically viable. Additional corrosion protection measures, such as protective coatings such as rubber coating, have a limited service life in the oil environment.

SUMMARY OF THE INVENTION

These problems are solved by a method of anticorrosive protection of equipment that comes into contact with oil or sludge _from a continuous or periodic basis and oil extraction probes, which according to the invention consists in adding to the mined, transported and stored media metal corrosion inhibitors containing amines and unsaturated alcohols.

Preferably, 10 to 50 L of an aqueous octadecylamine emulsion containing 1 to 20 wt.% Is injected into the probe every second working hour to protect the oil wells during intensification of the carbon dioxide extraction. % octadecylamine and 0.0001 to 0.1 wt. unsaturated alcohol, in particular, propargyl alcohol.

Other devices that come into contact with the oil or sludge continuously or periodically are preferably treated with octadecylamine dissolved in ethanol at a concentration of 0.001 wt%. up to 0.1% by weight _; . with propargyl alcohol at a concentration of 0.001% w / w, up to 0.1% w / w and a synergistic 0.0001% w / w sodium salt of mercaptobenzothiazole.

At tonne amounts of off-water from oil, electrochemical protection is preferably applied, in which equipment which comes into contact with oil or oil sludge, including oil wells, and in particular reservoirs, is a cathode and in the off-water a resistant "sacrificial" anode .

Preferably, the pH of the aqueous phase is further adjusted to 8.5-9.5 with substances selected from the group consisting of ammonia, hydrazine, cyclohexylamine, aminoalcohols, morpholine, piperidine.

For a carbon dioxide environment, and since water is almost always present and carries a number of dissolved salts (even hazardous chlorides), this mixture is per probe and even 5%. · 3 its surrounding equipment highly corrosive. Therefore, a film-forming fatty amine with propargyl alcohol, which forms a hydrophobic film on the walls of the device, is suitable for protection.

In places of permanent contamination of the water phase plus salt, in tons, at a certain delay, the device can advantageously be brought into the cathode conditions by means of an industrial potentiostat and in the aquatic environment a "sacrificial" anode can be situated.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

Pressurized carbon dioxide injected into the probe was used to intensify oil extraction. As a corrosion protection in an acidic environment (carbon dioxide), the device is protected by the use of film-forming fatty amines which, by sorption on the probe surface, render it hydrophobic and protect it from acidic carbon dioxide, the acid component of which will be eliminated by addition of propargyl alcohol. Therefore, 15 liters of 10% w / w aqueous octadecylamine emulsion were injected into the probe every working hour

-τύ, with 0.01 wt. propargylalcohol.

Example 2

The sedimentation of the emulsified water rose to 200 tons and therefore electrochemical protection was applied. The cathode was a 18/8 + 2 wt. - 700 mV vs. Mo, SKE, compared to anode, steel grade. 11, + 650 mV vs. SKE. The potentials were maintained by an industrial potentiometer.

Example 3

In the case of storage of crude oil containing large amounts of water, it was necessary to adjust the pH to 9 by using hydrazine together with 2 mg / l of mercaptobenzothiazole sodium in 1 liter of water. Electrochemical protection could also be used.

..: 4

Industrial use

The used corrosion protection method according to the invention, optionally in combination with unsaturated alcohols and electrochemical protection, has wide application in the refining and petrochemical industries.

Claims (5)

Patent claims 1. A process for corrosion protection of mining equipment, transportation and storage of oil • ^_t: / characterized in that the mined, transported and stored media added metal corrosion inhibitor comprising fatty amines and unsaturated alcohols. Method according to claim 1, characterized in that 10 to 50 liters of an aqueous octadecylamine emulsion containing 1 to 20% by weight of water is injected into the probe every second working hour to protect the oil extraction wells during the intensification of the carbon dioxide extraction. % octadecylamine and 0.0001 to 0.1 wt. unsaturated alcohol, in particular, propargyl alcohol. 3. A process for the protection of further equipment which comes into contact with oil or sludge continuously or periodically, according to claim 1, characterized in that they are treated with octadecylamine dissolved in ethanol at a concentration of 0.001% by weight. % to 0.1 wt%, with propargyl alcohol at a concentration of 0.001 wt%. up to 0.1 wt% and synergistic 0.0001 _; % wt. sodium mercaptobenzthiazole. Method according to one of Claims 1 to 3, characterized in that at tonne amounts of water withdrawn, electrochemical protection is further applied in which the devices which come into contact with oil or sludge, including oil wells, and in particular the reservoirs are cathode and Indented water is a resistant "sacrificial" anode. A process according to any one of claims 1 to 4, wherein the pH of the aqueous phase is adjusted to 8.5 to 9.5 with a substance selected from the group consisting of ammonia, hydrazine, cyclohexylamine, aminoalcohols, morpholine, piperidine.