Study on quantitative risk analysis of leakage and diffusion in supercritical CO₂ pipeline accidents

To study the impact of supercritical CO₂ pipeline leakage on the surrounding personnel, according to the physical characteristics of supercritical CO₂ and occupational exposure limits, combined with the risk assessment criteria for natural gas pipeline transportation, in this study, a criterion suitable for quantitative risk assessment of CO₂ pipelines was established and a quantitative risk analysis method for supercritical CO₂ pipelines was proposed. Taking a specific location in a Class Ⅱ high-consequence area of a certain project as case study, considering the actual pipeline design parameters, the environment along the pipeline, population distribution, and the distribution of specific locations, a CO₂ pipeline accident leakage dispersion model was established to conduct social risk and individual risk analysis for the high-consequence area. The results show that the individual risks and social risks of residential areas and other protection targets outside the boundary of the high-consequence area are acceptable. The research results provide a reference for quantitative risk analysis of accidents in supercritical CO₂ pipelines and enable reasonably predicting hazardous areas in construction projects, providing a scientific basis for determining the safe distances of pipelines and stations.