In support of national roadmap towards energy transition via Malaysia’s National Energy Transition Roadmap (NETR), PETRONAS has pledged to cap carbon emission at 48.6 Million tonne CO2e by 2024. However, one of the fields currently being developed by PETRONAS would have gas production containing CO2 up to 300mmscfd. PETRONAS foresees challenges to keep with the pledge as cumulatively the ‘would-be’ emitted CO2 will exceed the targeted value. As such, a Carbon Capture and Storage (CCS) project involving among others, a 137km of 16-in subsea pipeline have been sanctioned.

Having a CCS project, selecting materials for subsea CO2 pipeline can be an arduous task. It demands thorough approach to address several critical factors i.e. water droplet that may form during pipeline depressurization could pose a notable threat, potentially accelerating internal corrosion thus impairing pipeline integrity. The risk of internal corrosion due to CO2 necessitates appropriate material to resist or cater for corrosive environment. In addition to that, blowdown activity will create a very low temperature, in some cases, it may go lower than to -60°C that compound the challenge in selecting pipeline material.

Besides that, maintaining ductile fracture resistance is also of paramount importance for CO2 pipeline integrity and safety. Rigorous testing such as Charpy Impact and Drop Weight Tear Test (DWTT) evaluate the material’s ability to arrest fracture that is crucial for preventing catastrophic failures. Together with blowdown minimum temperature consideration, compliance with industry standards such as API Spec 5L and DNV-ST-F101 is fundamental, as these standards provide comprehensive requirements for line pipe properties, welding procedures, and essential testing requirements towards ensuring CO2 pipeline meeting safety and technical criteria.

This paper presents the holistic approach in managing challenges of material selection for CO2 pipeline, emphasizing all concerns and addressing pertinent decision-making process, towards achieving safe and efficient transportation of CO2.