Dynamic Well Failure Modelling and Well Integrity Quantitative Risk Analysis: Total Energies E&P Denmark Enabling Safer Wells with Increased Production Uptime

Abstract A well failure model is constructed as a matrix that identifies the most common modes of well failure seen by the Well Operator (ISO TS16530-1, 2017). For specific well types, well anomalies are assessed before they happen, in a pre-emptive risk assessment. This pre-emptive approach to well integrity risk assessment is hugely valuable when applied effectively. An earlier SPE paper (Girling, McIntosh, Lumbye et al, 2020) describes the benefits of the Analytical Well Failure Model (WFM) developed by TotalEnergies E&P Denmark's (TEPDK) as below. Engineers now spend 85% less time in well integrity risk assessments and failure management when anomalies arise because this work has been done in advance. The company also saves management time, onshore and offshore, cutting down the need for management challenge and action justification. All personnel involved have a more consistent understanding of well issues, with routine anomalies dealt with much more efficiently. This means decisions are made at a lower level, including whether to continue to operate a well or shut it in. TEPDK has reduced the probability of process safety incidents from wells. This is because it has a far more sophisticated, clearer understanding of well risks, and actions and timeframes for anomaly response. It has also improved production efficiency, safeguarding on average 2,700 boepd, through a reduction in well shut-in time. TEPDK has now upgraded the Analytical WFM to a Dynamic WFM with an enhanced, software-based methodology. This integrates quantitative risk analysis (QRA) into their routine well integrity risk assessments process. This innovative approach empowers a faster, more comprehensive, and accurate understanding of well integrity risks and removes subjectivity from the risk assessment process. The original Analytical WFM was built in a spreadsheet which took over 15 hours to run a single analysis. The Dynamic software based WFM significantly enhances decision-making by analysing tens or hundreds of thousands of potential leak paths and failure scenarios across multiple pressure source-sink combinations in seconds. Risk is presented visually in a functional Well Barrier Diagram (WBD) which helps communicate a standardised understanding of risk effectively and intuitively across teams. The model enables well-specific risk assessments, tailored to the nuances of individual wells. Engineers are empowered to input real-time well data, visualise risks dynamically, and refine action and response plans with clarity and precision. Multiple failure scenarios can now be analysed in a short period of time. This new methodology has not only further reduced the time required for risk assessments and removed subjectivity from the risk assessment process and has also elevated the accuracy and depth of analysis, leading to safer wells and improved production efficiency. TEPDK's Dynamic WFM is a transformative step forward in well failure modelling and wells QRA, offering a scalable approach to redefine industry standards.