Speaker
Description
The hydrogen economy is advancing yet confronts significant challenges, particularly in hydrogen transportation via pipelines. With its extensive gas transmission network connected to the European Union, Ukraine presents a unique opportunity for hydrogen transportation. In this study, the challenges for repurposing existing natural gas pipelines in Ukraine for hydrogen transportation are considered. They are mainly related to the risk of hydrogen embrittlement of pipeline steels and deterioration of the mechanical properties of steels due to long-term operation. The fracture mechanics approaches in meeting the challenges are considered and the role of hydrogen-induced stress in damaging and strain ageing of pipeline steels is analysed. The fracture toughness of pipeline steels from the Ukrainian natural gas network under varying hydrogen concentrations and specimen displacement rates using the J-integral method was investigated. A methodology for evaluating the serviceability of pipelines at hydrogen transportation, based on the criterion of operational decrease in fracture toughness of pipeline steels under hydrogen influence, is proposed.
