Leakage hazard distance of supercritical CO2 pipelines through experimental and numerical studies

Carbon emission reductions is gaining increasing attention in various countries, and the risk of leakage is inevitable in the transport of captured CO2 to storage. In view of how to accurately explain the diffusion law after leakage occurred from the high-pressure CO2 pipeline, this paper describes experimental studies on the diffusion of atmospheric CO2 in full-size burst discharge tests of pipelines containing high-pressure supercritical phase CO2, combined with computational fluid dynamics (CFD)simulation technique, based on the heterogeneous assumption and the diffusive source assumption, the whole leakage process is divided into a jet segment and a diffusion segment, the leakage continues by means of the de inheritance method with the release data acquired from the jet segment as a new diffusion source, and a numerical model of the high-pressure CO2 leakage jet and diffusion process is constructed segmentally to analyze the leakage characteristics after the rupture of the high-pressure CO2 pipeline. The CFD models were validated against the experimental data. Based on the analysis of the data, a prediction model for the leakage hazard area of different caliber pipes is proposed, and the relationship between the caliber of the supercritical CO2 leakage and the dangerous distance is quantitatively analyzed, which provides a feasible method for the specific determination of the leakage hazard of supercritical CO2 transportation.