Carbon capture and Storage (CCS) has been identified as a key abatement technology for achieving a significant reduction in carbon dioxide (CO2) emissions to the atmosphere. A central part of an efficient CCS system is transportation of CO2 by pipelines.

There is significantly less industry experience for transporting CO2 by pipelines than for hydrocarbon service. However over recent years, the CCS sector has matured, and experiences have been gained through R&D and projects, especially for pipelines, where the DNV guideline DNV-RP-F104 now provides guidance on “Design and operation of carbon dioxide pipelines”. One of the corner stones of this guideline, is definition of a fracture arrest criterion for avoidance of running ductile fracture for pipelines transporting CO2, as the risk of running ductile fracture is higher for a CO2 than a conventional hydrocarbon pipeline.

This paper presents practical experience gained from the Bifrost protect, which involved qualifying an existing 24” Natural Gas pipeline for future transport of CO2, applying DNV-RP-F104 as basis. From the study challenges related to the conversion are identified and highlighted. Challenges are often related to definition material properties where representative Charpy V-notch values play into the design against running ductile fracture. The paper includes a practical approach for definition of the Charpy V-notch toughness based on as-built tally lists and the material certificates providing input for the dispersion and risk modelling.