Study on Leakage Monitoring Method of Supercritical CO₂ Long-Distance Pipeline

The carbon capture, transportation and storage technology is an important option to achieve carbon peak and carbon neutralization. In order to prevent the pipeline fracture propagation, human injury and medium loss during the longdistance CO₂ pipeline leakage, it is necessary to establish the on-line leakage monitoring technology. At present, there is not enough understanding of the law of pressure response and phase change during the leakage of CO₂ pipeline, and there is still a lack of accurate leakage monitoring method based on the propagation law of decompression wave. Based on the release experiment data in the industrial scale pipeline, combined with the theoretical analysis, the pressure drop-rebound mechanism as a result of wave propagation at the moment of rupture was studied. The attenuation law of decompression wave strength will be researched for the establishment of the monitoring method of pipeline leakage position and orifice diameter. The reliability of the monitoring method considering the effect of flow state on the leakage characteristics of CO₂ pipelines was studied and a modified algorithm for higher measurement accuracy was proposed. This study was of great significance to the stability and safe operation of CO₂ long-distance pipeline system.