Real-Time Process Twin for CCS: A Critical Tool for Risk Management and Operational Insights

Abstract This paper details the importance and value derived from a real-time process twin model for one of the world's largest operating CO2 sequestration projects. The model provides real-time monitoring and forecasting of key flow assurance parameters, including pressures, temperatures, densities, and impurity concentrations throughout the CO2 system. The process twin serves as a vital operational tool, guiding operators to mitigate risks associated with water dropout and rapid corrosion during shut-in conditions. The operators can potentially extend the time to react to an unplanned shut down or trip, saving significant daily operational costs. The real-time process twin model has been calibrated against years of field data under varying conditions. It incorporates ambient factors, CO2 impurity concentrations, and instrumentation data to predict operating conditions across the pipeline network. Additionally, the model provides virtual metering as a contingency for injection well flow meters, ensuring accurate flow monitoring in circumstances where physical metering is lost. Efforts taken to validate the model against the real field data revealed that the initial conditions significantly influence the model's predictive accuracy; even minor variations in temperature or pressure can lead to drastically different outcomes. The model successfully matched observed pressures and temperatures during an actual field shutdown event, underscoring its reliability due to thorough calibration and consideration of heat transfer dynamics. As the amount of heat stored in the soil depends on the operating conditions weeks prior to the shutdown event, the importance of a real-time model, rather than relying solely on an offline engineering simulator, is highlighted. The findings demonstrate that the model can effectively forecast system behavior, providing operators with critical insights and response times for unplanned shutdowns. This paper contributes novel insights on the importance of a real-time model for CO2 transport through field validation and sensitivity analyses involving changes in impurity concentrations, heat transfer properties, and initial system pressures and temperatures. These analyses create a comprehensive catalog of results that enhances understanding of the factors influencing CO2 transport and sequestration, thereby ensuring the ongoing success of future decarbonization projects.