Assessment of Corrosion Inhibition in Crude Oil Pipelines and Management Strategies in the Niger Delta, South South Nigeria

Internal and external corrosion of crude oil transmission pipelines in the Niger Delta remains one of the principal causes of pipeline failures, oil spills, and associated environmental and economic losses, demanding professional management strategies grounded in corrosion chemistry. This study assesses corrosion inhibition practices applied in crude oil pipelines operated by a midstream company in the Niger Delta region, South South Nigeria. A structured technical audit reviews the current corrosion inhibitor injection programme, including inhibitor chemical composition, dosage rate, injection frequency, and performance monitoring methods. Corrosion rate data derived from corrosion coupons and electrochemical linear polarisation resistance measurements are collected from six pipeline segments over a six-month monitoring period. Pig inspection data and ultrasonic wall thickness measurement records are reviewed to assess internal corrosion progression rates. Water chemistry analysis of produced water, including chloride content, carbon dioxide, hydrogen sulphide, dissolved oxygen, and microbial population counts, informs the assessment of microbiologically influenced corrosion risk. Inhibitor performance is evaluated using polarisation curves in laboratory-simulated brine environments containing pipeline-representative produced water. Alternative inhibitor formulations based on plant-derived compounds, with established inhibition efficiency in the literature, are reviewed as supplementary options. A professionally structured corrosion management improvement plan is prepared for submission to the company's pipeline integrity management team. Keywords: corrosion inhibition, crude oil pipelines, Niger Delta, pipeline integrity, produced water