Carbon neutralization is gaining increasing attention in various countries, and the risk of leakage is inevitable in the transport of captured CO2 to storage. High pressure Carbon Dioxide (CO2) pipeline transport is an important component of the Carbon Capture Utilization and Storage (CCUS) chain. Hence, accurate estimation of the leak caliber is an important component in determining the risk level when leakage happens. Carbon dioxide leaks are hazardous accidents, and accidental releases from pipeline transportation can lead to catastrophic damage. To ensure safety in the process of pipeline transportation, it is necessary to understand the impact of different leak sizes on the risk range after the occurrence of a pipeline failure. In this paper, a proposed model for estimation of pipe leak caliber based on back analysis through experimental and numerical studies. First establishes that the danger of CO2 leakage from supercritical phase transport using a large pipe experiment (258 m long, internal diameter is 233 mm). Then a two-stage Computational Fluid Dynamics (CFD) model to predict different caliber supercritical phase CO2 leakage ranges was proposed, and the CFD model was validated by experimental data. The error between numerical simulation values and experimental results is within 5%. The numerical model calculated the leakage ranges at different calibers, back analysis of the CO2 concentration data, a model capable of predicting leakage caliber by leakage range is proposed. When a leakage accident of a pipe occurs, the leakage caliber is confirmed by this model, which provides a new method for determining the time of appearance of leakage.
Keywords CCUS, Greenhouse gases, CFD, Back Analysis, Safety engineering