Approaches to the selection of material design of infrastructure facilities for transport and injection of СО2

The article is devoted to the study of dependence of carbon dioxide corrosion rate on the microstructure of material design of the pipeline for CO 2 transport and injection. Today there is a task of choosing such material design. For pipeline construction the most cost-effective materials are carbon steels, but for their application it is necessary to pay increased attention to the problem of carbon dioxide corrosion, which is intensified in wet, undrained CO 2 flows. At the same time, the choice of material should be made reasonably, taking into account the balance between corrosion resistance, mechanical characteristics and economic aspect of the issue. In this paper, the influence of microstructural state features on the corrosion rate of low-alloy mild steels for CO 2 transport and injection was investigated. The authors studied the features of steels with ferritic-bainitic, bainitic-ferritic-perlitic and ferritic-perlitic microstructures. Tests on corrosion resistance were carried out on the bench autoclave complex, which allows to recreate conditions of high pressure and temperature and to simulate real environments. It was determined that the microstructural state of steel has a significant effect on the corrosion rate, which increases with increasing volume fraction of pearlite. Understanding the relationship between the microstructural characteristics of steels and corrosion rates can simplify material selection for infrastructure facilities and contribute to more efficient and reliable use of low-alloy carbon steels in carbon capture, use, and storage projects. This study will be useful in selecting favorable microstructures for low-alloy mild steels that can be used for CCUS (Carbon Capture, Use and Storage) infrastructure projects.