Effect of Imidazoline Inhibitor Used in Outflow System of Tower Processing Thick Oil

The corrosion mechanism of overhead system of visbreaking tower of a refinery in Liaohe was studied by gas chromatography of corrosion media and XRD of corrosion products. The corrosion inhibitor for 20 steel in the corrosion media was studied by static weigt loss method and electrochemical polarization curves. The results showed that 20 steel samples in the water medium in the top of the visbreaking tower suffered low temperature HCl + H2S +H2O corrosion markedly. The main ingredient of A1 corrosion inhibitor is imidazoline. Al is an anodic corrosion inhibitor which can form hydrophobic protective layer on the surface of 20 steel. When the best concentration of A1 was 100 mg/L the inhibition efficiency was 84%.