CO₂ Safe&Sour Joint Industry Project (tidligere: H2S Challenges in CO₂ pipelines)

Background
The background for the project was a need to provide clearer guidance on the impact of H2S and other impurities in the CO₂ pipelines with a key focus on risks such as sulfide stress cracking (SSC), chemical reactions and corrosion.

Project objective
The objective of the joint industry project was to provide clearer guidance related to level of H2S in the CO₂ stream to be transported in CCS pipelines. The project worked to assess the impact of increased H2S levels to the risk for SSC and uniform corrosion. The project carried out targeted testing, simulations and gathered expert input from participating companies. The project provided general recommendations for industry wide use for implementation in DNV-RP-F104, which is DNVs recommended practice document for Design and operation of carbon dioxide pipelines.

Activities
The project carried out targeted testing, simulations and gathered expert input from participating companies. A key activity in the project have been to gather experts on SSC, chemical reactions and corrosion across the different companies engaged in CCS to share knowledge and align on how research should be carried out.
It should be noted that the project was extended to include additional participants and to increase the scope of work beyond the CLIMIT supported initial project.

Results
The project has developed test procedures, carried out testing and generated test results for evaluating various types of risks related to H2S. The different experimental works included SSC testing, fracture mechanics testing in environment, hydrogen permeation testing, chemical reactions testing and corrosion testing. Based on the different test programs carried out, the project has formulated recommendations for industry wide use on how to consider H2S in CO₂ compositions, both from a sulphide stress cracking perspective and from a corrosion and chemical reactions perspective. Recommendations will be included in the next issue of DNV-RP-F104.

Future plans
One of the key questions that raised during the project was to establish if standardized testing developed over several decades, for taking into account the presence of H2S in oil and gas operations, can be transferred to CO₂ pipelines. The project established a promising outlook for this, but was not able to give a final conclusion of this. Based on this, a follow up phase of the project is planned to continue working on this topic and to generate further research data on the topic.

Publications
[1] Update of DNV-RP-F104 “Design and operation of carbon dioxide pipelines”

[2] Is the Standardized SSC Testing Approach Applicable for Dense Phase CO₂ Applications? K Solberg, K Lønvik, R Rizzo, E Østby, B Leinum, G Heiberg AMPP CONFERENCE 2024, 1-11

[3] Impurity reactions in subsea CO₂ pipelines, G Svenningsen, BH Morland, K Solberg, Available at SSRN 5016341