Modelling and Simulation of Cryogenic Liquid Co2 Transportation Systems for Hot Climates

Abstract

This study presents a steady-state modeling framework to analyze the axial temperature and pressure gradients, as well as the flow behavior, of cryogenic liquid CO2 transported through pipelines linking carbon capture facilities to utilization or storage sites such as enhanced oil recovery operations. A discretized one-dimensional model was developed to simulate the coupled hydraulic and thermal behavior of liquid CO2, solving the governing mass, momentum, and energy balances along finite axial pipeline segments. Thermophysical properties were evaluated using regression-based correlations derived from NIST data calculated with the Span–Wagner equation of state, while heat transfer mechanisms were incorporated to account for external heat gain under high ambient temperatures and solar radiation typical of arid Gulf environments. The model was used to determine the maximum allowable pipeline length before vaporization and to assess the influence of key design and operating parameters. Results show that lower inlet temperatures, higher inlet pressures, and improved insulation significantly extend the stable liquid transport distance, with aerogel insulation providing the best thermal performance despite higher capital cost. Conversely, higher ambient temperatures, smaller pipe diameters, and increased frictional losses reduce the allowable length. Mass flow rate exhibited a dual effect by limiting temperature rise while increasing pressure drop, indicating the existence of an optimal operating range. Overall, the study demonstrates that reliable liquid-phase CO2 transport in hot climates requires a balanced compromise between thermal design and hydraulic performance, and it provides a region-specific modeling approach to support the development of thermally resilient CCUS pipeline infrastructure.