Pickling inhibitor and preparation method thereof

Abstract

The preparation method for inhibitor used in convey-halogen pipe comprises: dissolving and mixing the material with amine salt, thiocyanic acid, ethanediamine derivative, surfactant, carboxylic acid and water; before using, adding surfactant and carboxylic acid, stirring evenly, and adjusting proper concentration with water. This invention can prevent overpickling and hydrogen embrittlement effectively, reduces gas pressure on pipe, improves working condition greatly, and has wide application for device protection.

Description

technical field [0001] The invention belongs to the field of metal anticorrosion, in particular to a corrosion inhibitor suitable for brine pipelines and a production method thereof. Background technique [0002] After the carbon steel brine pipeline has been used for a period of time, due to the influence of the brine composition, the inner wall of the pipeline is severely scaled, which affects the amount of brine, increases the transmission power of the brine pump, and increases energy consumption. Therefore, pickling and descaling must be carried out. The washing liquid has a certain corrosive effect on the pipeline and related conveying equipment. [0003] In order to protect the material and related equipment during the pickling process, a certain amount of corrosion inhibitor is generally added to the pickling solution to form a protective film on the surface of the material and equipment to protect the material and related equipment. [0004] In this brine environmen...

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Problems solved by technology

[0007] At present, ordinary commercially available corrosion inhibitors are generally used in the pickling of the salt production system, and the corrosion inhibition effect is not good in practical applications. Mixed crystals composed of carbonate type and sulfate exist, which are closely combined with the surface of the material. It is difficult for general corrosion inhibitors to penetrate the scale layer and cover the surface of the material, which cannot provide good protection. At the same time, due to the existence of carbonate, Pickling is to release a large amount of carbon dioxide gas, resulting in too high local pressure, which is easy to cause pipe burst and affect the progress of the project, and the released waste water is serious for environmental pollution