Experimental research on the fracture and arrest process of supercritical CO2 pipelines

As global greenhouse gas emissions become increasingly severe, carbon capture, utilization, and storage (CCUS) technology, as a major approach for achieving carbon peak and carbon neutrality, is attracting growing attention. Pipeline networks play a crucial role in implementing CCUS technology, connecting carbon sources from capture points to storage facilities. However, pipelines are inevitably susceptible to leaks or ruptures due to various factors, which can lead to catastrophic accidents. Research on the pressure and temperature inside pipelines after the rupture of defective pipelines, as well as the mechanisms of crack propagation and diffusion behavior, forms an important foundation for risk assessment of CO2 pipelines. This research will provide effective technical support for the implementation of large-scale CCUS projects and contribute to pipeline safety. In this study, an API X52 full-scale CO2 pipeline rupture experiment was conducted, and data from various sensors and instruments were collected to track the pressure evolution, temperature changes in both axial and vertical directions, microscopic morphology of cracks at different locations, and the evolution of gas clouds from leakage to rupture. The developed pressure relief wave prediction model showed high consistency with experimental results, and the safe design of the experimental pipeline was conducted based on the modified Battelle two-curve method (BTCM).