The role of hydrogen gas in SRB-induced degradation of X80 pipeline steel in hydrogen-blending environments

The pipeline transportation of hydrogen poses higher challenges to the safety of pipes. In this study, the corrosion mechanisms of SRB in X80 pipeline steel under H₂ conditions were investigated. Thermodynamic analysis revealed that the introduction of hydrogen enhances SRB metabolic activity, facilitating the reduction of sulfate to sulfide and promoting hydrogen embrittlement. Additionally, hydrogen permeation tests confirmed that SRB significantly increase hydrogen diffusion in steel, accelerating corrosion. The enhanced hydrogen permeation under biotic conditions was linked to increased hydrogen uptake and sulfide formation, which further destabilized the steel microstructure. This study provides critical insights into the interplay between microbial activity, hydrogen permeation, and corrosion, offering a deeper understanding of the factors influencing hydrogen-assisted corrosion in steel pipelines. The findings contribute to the optimization of material performance and risk assessment in hydrogen-blended environments.