Life Cycle Asset Integrity Management Strategy of Aging Crude Oil Pipelines

This study developed an asset integrity management strategy to ensure continuous safe operation of the 24in Trans-Niger pipeline case-study till its design end-of-life in 2025 and life-extension thereafter, despite low flow conditions and associated ongoing Microbiologically Induced Corrosion (MIC). The case-study for the work is a 24inches by 55km carbon steel oil pipeline which was commissioned in 1995 to evacuate production from four (4) flow-stations to an export terminal. In the course of the work, a critical analysis of the current pipeline integrity management system (PIMS) in place against industry best practices was carried out. A Corrosion Management System (CMS) for the pipeline asset was developed by defining a company-wide corrosion policy for this pipeline, conducting a corrosion risk assessment for the threat of low flow conditions, carrying out a Failure Mode and Effect Analysis for low flow condition, proposing an Integrity Management Team and developing a roadmap for the execution of the proposed Integrity Management System. Both quantitative & qualitative data were employed in carrying out the study scope of work. Quantitative data used in the study included: pipeline design/as-built data, inspection & monitoring data, historical production data, and pipeline integrity management system. While qualitative data was derived from interviews and discussions with pipeline integrity and operations personnel. From the analysis conducted, a goal of zero corrosion leaks on the 24in Trans-Niger pipeline would be achieved through the Corrosion Management Strategy managed by the Head of Pipeline Integrity. The output of the FMEA rated the criticality of failure mode as high due to the product of the susceptibility of failure and Asset, Environment, and reputation consequence. An essential component of the CMS is the CMS execution team composition and their interdependencies, as CMS execution requires team effort with clear responsibilities and accountabilities. This study concluded that Asset Integrity Management without following best practice or industry standard methodology is grossly ineffective and would lead to dire consequences as in the case of the 24in Trans-Niger pipeline case-study with its failure in 2018.