Corrosion inhibitor suitable for high-salt and high-chlorine working conditions and preparation method thereof

Abstract

The invention discloses a corrosion inhibitor suitable for high-salt and high-chlorine working conditions. The corrosion inhibitor is prepared by compounding a component A and a component B according to a mass ratio of (1.5-2): (0.8-1.2), wherein the component A is prepared from mercaptobenzotriazole, dimethylformamide, sodium dodecyl benzene sulfonate, sodium borate and sodium nitrite; the component B is prepared from organic amine, sodium hydroxide and benzyl chloride; the density of the corrosion inhibitor is 1.0-1.3 g.cm <-3 >, the freezing point is less than-7 DEG C, and the pH value is 4-7. The corrosion inhibitor prepared by the method can effectively slow down corrosion of metal equipment under high-salt and high-chlorine working conditions, and is excellent in corrosion inhibition performance and low in cost.

Description

technical field [0001] The invention relates to the technical field of petrochemical industry, in particular to a corrosion inhibitor suitable for high-salt and high-chlorine working conditions and a preparation method thereof. Background technique [0002] Corrosion is one of the serious problems in oilfield production. Especially with the continuation of oilfield development, the emergence of corrosive media such as high salt ions and chloride ions has caused serious damage to oilfield metal equipment. The corrosion of oilfield equipment directly affects the normal production of the oilfield, causing huge economic losses and potential safety hazards. [0003] Under high-salt and high-chlorine conditions, oilfield produced water contains a large amount of salts, mainly including sodium chloride, magnesium chloride and calcium chloride. Chloride ion is a common corrosive ion in the crude oil production process. The presence of chloride ion will cause pitting corrosion and ...

AI Technical Summary

Problems solved by technology

The scale and corrosion inhibitor prepared by this patent application avoids the use of phosphorus-containing compounds and non-renewable molybdate or tungstate, etc., and has the characteristics of phosphorus and nitrogen-free; and has high tolerance to calcium and alkali, high The corrosion of chloride ions and sulfate ions with high concentration has a wide range of adaptability to water quality, but the corrosion effect and corrosion inhibition performance caused by high salt content in produced water are not yet clear

[0007] At present, the commonly used high-salt and high-chlorine corrosion inhibition methods in the market are to reduce the corrosion rate through the treatment of high-salt and high-chlorine corrosive media under complex process flow, and the research on corrosion inhibitors for high-salt and high-chlorine environments is not deep enough.

For example, the compounding and performance research of corrosion and scale inhibitors for high-chloride and high-salt heavy oil produced water (Guangzhou Chemical Industry, 2016.2.23) discloses that the corrosion and scale inhibitors are suitable for high-chloride and high-salt heavy oil produced water, and the corrosion inhibition rate can reach More than 85%, but no research has been done on its inhibition against different forms of corrosion

[0008] Moreover, in the harsh environment of high salt and high chlorine, the corrosion inhibition effect of conventional corrosion inhibitors is significantly reduced, or even disappears.

Salt ions and chloride ions can hinder the adsorption and film formation process of corrosion inhibitors on the metal surface, destroy the corrosion inhibitor protective film and metal passivation film, and cause the corrosion inhibitor to fail

Images