Control of Stray Current Corrosion by Application of Corrosion Inhibitor

Abstract In oil and gas production operations, multiple sources of voltages and currents are prevalent due to the necessity of various motors, pumps, and cathodic protection systems. Unintended current flow can occur through undesired paths caused by grounding issues or failed electrical insulation, leading to severe corrosion that compromises asset integrity. Traditional mitigation methods include cathodic protection, insulation, and coatings. However, these methods require substantial capital investment and result in considerable downtime. This paper explores a more cost-effective approach using Corrosion Inhibitor A (CI-A) to control stray current corrosion, employing various electrochemical techniques. Linear Polarization Resistance (LPR) tests were conducted to evaluate the inhibition performance of CI-A on general corrosion at different concentrations. Additionally, the effectiveness of batch treatment with CI-A was analyzed in the same manner. Polarized sweeps were performed on the differently treated coupons to simulate stray current conditions. The results indicated that batch treatment with CI-A provided superior protection against stray current, as it resulted in the lowest current under the same polarization. An anodic "limiting current" was observed, demonstrating that the batch treatment could inhibit corrosion up to a higher potential. This passive-like behavior also exhibited negative hysteresis, further underscoring the efficacy of the batch treatment approach.