The invention discloses a filming
corrosion inhibitor, which at least comprises 30 to 50 percent of octadecylamine, 20 to 30 percent of imidazoline
amide, and
reducing agent carbohydrazide being the rest, the above proportion is
mass percentage. Under the condition that the temperature is 150 to 500 DEG C, the concentration of the filming
corrosion inhibitor is 10 to 35 ppm, the pH valve is 7 to 11, and the
time duration is 1 h to 10 min, the filming
corrosion inhibitor can produce a compact protective film on the
metal surface, and the function of preventing the
metal to be corroded in the atmospheric environment is realized, especially the invention can be applied during the thermal power
plant to stop the boilers for protection, the protective film with strong hydrophobicity and good
erosion resistance can be produced on the
metal surface inside the
water vapor system of the thermal equipment, and the thermal equipment can be protect from being corroded for more than 8 months during the exposition in atmospheric environment, simultaneously, the invention has certain cleaning, uncovering, and removing function to the incrustation and the corrosion product on the metal surface of the thermal
system, the probability of the thermal equipment corrosion and the four-tube blasting is reduced, the invention is advantageous for extending the acid
pickling cycle of the boiler, the service life of the equipment is prolonged, the security is enhanced, and the economic benefit is increased.