Pre-filmed carbon steel coupons immersed in corrosive oxygen saturated brine were studied at varying levels of shear stress. The laboratory evaluation assessed "batch applied" inhibitor films for providing mitigating benefits against oxygen degradation corrosion. Test protocols were designed to simulate a field pipeline environment in Western Canada challenging "continuous injection type" corrosion control strategies, using Zinc / phosphate chemistry for protecting carbon steel assets from further oxygen corrosion damage. The percent protection afforded by the batch filming inhibitors was compared to the performance of zinc / phosphate continuous injection treatments of non filmed coupons. Two batch inhibitor formulations provided very effective corrosion control against oxygen degradation corrosion on the laboratory tests. The results from this study indicate a .batch applied. corrosion control option is available for consideration in managing corrosion in pipeline environments transferring oxygen rich process brine. The two batch inhibitors performed superior to the Zn / phosphate chemistry in the comparative studies.
Key Words: oxygen corrosion, cathodic depolarization, oxygen depletion zone, pitting attack.