Heavy oil scale cleaning agent is mainly composed of compound surfactant

2019-10-18 10:02:26

In petroleum refining and petrochemical plants, the heavy oil and coke deposits in heat exchange equipment and pipelines are serious, which often need to be cleaned. The organic solvent is toxic, inflammable and explosive, while the general alkaline washing method is ineffective for heavy oil scale and coke scale. At present, the heavy oil scale cleaning agent developed at home and abroad is mainly composed of compound surfactants, which are composed of several non-ionic surfactants, anionic surfactants, inorganic detergent aids and alkaline substances. Composite surfactants not only produce wetting, penetration, emulsification, dispersion, solubilization and foaming effects, but also absorb FeS2. Generally, they need to be heated and cleaned above 80 ℃.

With surfactant, organic solvent and water as raw materials, a kind of hard surface oil scale cleaning agent with excellent performance was developed by the method of phase inversion emulsification. It can efficiently and rapidly remove the oil scale on various hard surfaces (such as kitchen stove, glass, porcelain piece, etc.), especially for the oil scale and coke scale on various metal surfaces.

When there is microbial slime in the cooling water system, the use of non oxidizing biocide and low foaming non-ionic surfactant as dispersant and penetrant can increase the activity of the agent and promote the agent to penetrate into the cell and the fungal slime layer. In addition, quaternary amine biocides are also widely used. They are some cationic surfactants, commonly used are jieermiao and xinjieermiao. They have the advantages of strong killing power, convenient use, low toxicity and low cost. They not only have the function of stripping slime and removing odor in water, but also have the function of corrosion inhibition. In addition, the compound biocide of quaternary ammonium salt and dithiocyanomethane not only has broad-spectrum and synergistic biocide effect, but also can prevent the growth of slime.

Surfactant is an additive which can produce significant effect on the corrosion inhibition process. It can increase the wettability, dispersibility and foaming, promote the contact of acid washing liquid with scale and rust, and change the surface state of the base metal after acid washing, so as to improve the quality of acid washing. Some surfactants also have a certain degree of corrosion inhibition performance, which can get better effect than using a single inhibitor component. Generally, the surfactant added in the inhibitor formula is anionic C10 ~ C18 alkyl or alkylbenzene sulfonate or alkyl sulfate, or nonionic higher alcohol and phenol polyoxyethylene compounds. But some inhibitors also have cationic surfactants, such as quaternary ammonium salt.

It has been reported that Tween80 has good corrosion inhibition effect on steel in three kinds of inorganic acid media (HCl, H2SO4, H3PO4); yuan lanbai et al. Studied the synergistic effect of dbsas and op on steel, and found that the combination of dbsas and op has good corrosion inhibition effect on steel. It has obvious synergistic effect of corrosion inhibition and wide range of compound concentration.