Corrosion of X80 steel in the co-existence of sulfate reducing bacteria and permeating hydrogen

Abstract

Purpose This study aims to shed light on the corrosion behavior of X80 steel when sulfate-reducing bacteria (SRB) and permeating hydrogen interact. Design/methodology/approach In this study, electrochemical tests were conducted between 25 and 55 °C, and the surface morphology of the specimen was observed using scanning electron microscopy and three-dimensional photos. The composition of the oxide film was characterized by X-ray photoelectron spectroscopy (XPS). Findings Under the condition of 6 MPa simulated natural gas (15% H2), the content of S-containing compounds (FeS and FeSO4) in the corrosion products on the surface of the specimen decreases from 60.8% to 54.4%. This finding indicates that hydrogen permeation inhibits the metabolic processes of SRB in this environment. By comparing the hydrogen-uncharged specimen, it was found that under the condition of 6 MPa simulated natural gas (15% H2) hydrogen charging, the uniform corrosion on the X80 surface was weakened, and the protection of the oxide film on the specimen surface in this environment was better than that without hydrogen charging. Originality/value To the best of the authors’ knowledge, most of these existing studies have focused on the effect of hydrogen on the mechanical properties of materials and very little is known about corrosion behavior in the hydrogen environment. In this study, a self-designed small gas phase hydrogen charging device was used to study the X80 surface corrosion behavior in the environment of the H2-doped natural gas pipeline.