Nuria Espallargas is a Professor at the Norwegian tribology center Department of Mechanical and Industrial Engineering (MTP) Norges teknisk-naturvitenskapelige universitet (NTNU). She has 20 years of research experience in surface engineering, chemistry, and tribology. Since 2011 she is the NTNU leader of the Norwegian Tribology Centre. Her research lies in the fields of surface chemistry and engineering, lubricants, tribocorrosion and nano-tribology. Her recent work in tribocorrosion focuses on improving the lifetime of components used in offshore renewable energy systems

 The role of tribocorrosion and multidegradation on the green energy transition While innovative Offshore Renewable Energy (ORE) technologies are gaining popularity, the technicalities of operating them in hostile environment remain complex and challenging jeopardizing the deployment of these very important technologies for the future generations. To succeed in the green energy transition, robust and reliable materials are needed for offshore conditions. Materials used in ORE devices suffer of tribocorrosion and multidegradation due to direct exposure to the marine environment in combination with mechanical loads resulting in tribocorrosion failures. Tribocorrosion can be considered a young research area which has experienced a boosting interest and development in the last 25 years due to the increasing demand from engineering systems that are subjected to the combined action of wear and corrosion (i.e. biomedical implants, mining equipment, manufacturing, nuclear power plants, food processing devices or marine equipment). To address this complex problem, which cannot be approached by simply considering both wear and corrosion separately, dedicated tribocorrosion research has been developed. In this talk, you will be introduced to tribocorrosion and multidegradation of materials with focus on passive metals and alloys, which are the most typically used materials in Offshore Renewable Energy devices. Their current challenges and methodologies with improved tools for material selection and validation will be discussed to help boosting the creation of the next generation of materials for Offshore Renewable Energy devices to overcome the present energy and environmental challenges.

Vigdis Olden is a senior research scientist at SINTEF Industry in Trondheim, Norway. Her main field is hydrogen embrittlement of metallic materials. She  is working in a research group where a large part of the project portfolio is related to the structural integrity of subsea infrastructure in oil and gas, including hydrogen.

SUBSEA PIPELINES – HYDROGEN EMBRITTLEMENT CHALLENGES IN NATURAL GAS AND HYDROGEN GAS TRANSPORT

«Since the late 1990s, hydrogen embrittlement in Norwegian subsea infrastructure for natural gas transport, caused by hydrogen from cathodic protection, has posed significant challenges for pipeline operators and energy companies. Through intensive research and development, the industry has learned to manage and mitigate these issues, incorporating the acquired knowledge into design and operational guidelines.

Currently, the industry is exploring the feasibility of repurposing this subsea infrastructure for 100% hydrogen gas transport. The existing Norwegian pipeline network spans 8,900 km and is primarily constructed from higher strength steel than onshore pipelines, making it more susceptible to hydrogen embrittlement. These pipelines are also designed for different loads and operating environments compared to onshore pipelines. The anticipated operating pressures and purity of hydrogen gas in the Norwegian subsea network are 150-200 bar and 100% hydrogen, respectively, which are higher than those in existing hydrogen pipelines.

Since 2019, SINTEF has been conducting the HyLINE I and HyLINE II projects to establish fundamental knowledge about the effects of hydrogen gas on pipeline steels and their weldments, aiming to enable the safe and efficient use of both existing and new subsea pipeline infrastructure. The research topics include hydrogen uptake and diffusion, nano- and micro-mechanical characterization, fracture toughness and fatigue, as well as numerical modeling for fracture assessment.

A summary of key findings within these research areas and their interconnections will be presented.»