Projects per year
This paper investigates the flexibility that exists within a dense phase carbon dioxide (CO2) pipeline network to accommodate upset conditions in the Carbon Capture and Storage (CCS) network, primarily due to flow variations or short term operational issues, by utilising the pipeline as storage vessel whilst still maintaining flow into the pipeline. This process is defined in the pipeline industry as “line-packing” and the time available to undertake line-packing is termed the line-packing time. This study investigates the impact of typical CO2 pipeline design parameters (diameter, wall thickness and length) as well as CO2 mass flow rate and pipeline inlet and outlet pressure on the available line-packing time and derives relationships between these variables to provide prediction tools that can be used at the pre-design stage to determine the impact of pipeline design and operation on the line-packing capability. It is shown that the line-packing capacity of the pipeline can be increased by increasing the available internal volume of the pipeline, reducing the mass flow rate into the pipeline, increasing the allowable operating stress and managing the inlet pressure and outlet pressures. This work has indicated that, for pipeline dimensions typical of those considered for CCS schemes, line-packing times of only up to 8 hours can be achieved, therefore the pipeline does not represent a long-term storage option. However, if line-packing capability is considered at the design stage then the level of flexibility for the pipeline to act as short-term storage in the network increases.