Given the high costs of carbon capture, utilisation and storage (CCUS), using shared CO2 transport and storage infrastructure and CCUS process integration in industrial clusters becomes critical for the economic rollout of CCUS on a large scale.

The task of techno-economic optimisation of CO2 transport in industrial CCUS clusters requires the formulation of safety and operation constraints on CO2 transport. In particular, solid CO2, commonly known as ‘dry ice’, can form upon near-isentropic CO2 decompression of CO2 to below its triple point pressure (5.18 bar) during controlled venting or accidental failure of CO2 transportation pipelines and storage tanks. Small particles and large agglomerates of solid CO2 may cause blockage of pipework and valves, accumulate in the system potentially leading to explosion overpressure, and upon their release to the atmosphere, result in injuries and damaging the process equipment.

Given that CO2 streams in CCS may carry significant amounts of impurities, it is important to identify those components that may increase the risk of solid CO2 formation in pipeline venting scenarios. To this end, this report aims at evaluating the impact of CO2 streams impurities on the formation of solid CO2 in pipelines for realistic venting decompression scenarios.