Equipment and Piping failures present the greatest risk to the integrity of metallic components in down-stream petroleum sector. The implementation of Mechanical Integrity (MI) systems in the downstream petroleum sector differs based on the interpretation of various Industry standards, etc. Despite implementation of MI system, failures leading to loss of containment (LOC) are ubiquitous in aging plants. Robust and effective corrosion assessment requires focused effort from many disciplines within the organization to ensure that threats and monitoring regime are fully, identified, understood, and managed.
Corrosion risk assessment is an effective tool for screening, assessing, and managing threat at the segment and sub-segment level. Consequently, effective equipment and piping segmentation based on fluid corrosivity is paramount towards initiating corrosion-risk assessment or risk-based inspection (RBA/RBI) program. Corrosion assessment allows a review of inspection and operation data to review barriers and mitigations to ensure safe operations in accordance with the design intent. Corrosion risk management is undertaken through the following key steps; threat identification, risk assessment, risk response and risk review. This continuous, cyclical process is required to ensure that all risks are appropriately mitigated or managed.
This paper shares experiences and challenges of corrosion risk assessment in the down-stream petroleum industries and simplify ways of managing corrosion through effective corrosion assessment regime.
Many refineries and petrochemical plants are operating well beyond their original design life. Consequently, operating these plants beyond their design life presents safety and business risks as well as operational challenges. The mechanical integrity of equipment and piping of these plants presents enormous challenges in maintaining plant integrity and reliability. Implementation of rigorous corrosion risk assessment (CRA) is required to ensure all degradation mechanisms associated with aging are identified, understood and mitigation developed to reduce the risk. Some of the degradation mechanisms are listed in Table 1 below; a sample table containing some PDMs:1