Effects of Impurities on Anthropogenic CO<sub>2</sub> Pipeline Transport
Fuqiao Bai, Yingda Lu
Abstract
Efficient transportation of anthropogenic CO 2 from emission sources to storage sites or utilization facilities is vital to realize full-scale Carbon Capture, Utilization, and Storage (CCUS). The CO 2 captured from emission sources is often contaminated with impurities that can significantly affect its thermophysical properties and flow behaviors during pipeline transportation. A holistic understanding of the impacts of these impurities is necessary to establish a cost-efficient and reliable CO 2 pipeline transport system. In this study, we utilized an integrated thermophysical and fluid flow model and systematically analyzed the impurity effects of H 2, N 2, CH 4, CO, O 2, Ar, SO 2, H 2 S, and H 2 on the phase-envelopes, critical properties, density, viscosity, and pressure drop of CO 2 streams. Each impurity was studied from zero to its highest concentration encountered in CCUS. The impacts of different impurities might be positive or negative to CO 2 pipeline transportation depending on the system parameters being evaluated. H 2 generally produces the most negative impacts on transportation, greatly enlarging the two-phase region, most significant reductions in density and viscosity, and highest pressure loss. In contrast, H 2 S has a much milder effect on most system properties. In this paper, we also ranked the impacts of impurities on different system properties by grading the effect of each impurity at 5 vol % concentration and discussed their indications on CO 2 pipeline transportation. These results offer practical insights into the design, operation, and management of CCUS CO 2 pipelines nowadays and in the future.