Dehydration requirements for CO2 and impure CO2 for ship transport

CCS is expected to become an important contribution to the mitigation of carbon dioxide emissions. Trans-portation of CO2 from the capture site to the permanent storage reservoir plays a key role, and transportation by ship is now viewed as a relevant alternative for certain combinations of captured CO2 volume and distance.This paper presents experimental equipment, methods and new results for the water content of carbon dioxide and impure carbon dioxide in equilibrium with hydrates at temperatures between (-55 and-10)degrees C and pressures between (3 and 120) bar, hence in both vapour and liquid phases. The experimental data are compared with predictions from two thermodynamic models: the Cubic-Plus-Association equation of state and an approach using Multi-Fluid Helmholtz Energy Approximation (MFHEA) equations of state (EoS). In all cases, the hydrate -forming conditions are modelled by the solid solution theory of van der Waals and Platteeuw.