Potential influence of microorganisms on the corrosion of carbon steel in the French high‐ and intermediate‐level long‐lived radioactive waste disposal context

Abstract

In the context of the high‐level radioactive waste disposal CIGEO, the corrosion rate due to microbially influenced corrosion (MIC) has to be evaluated. In France, it is envisaged to dispose of high‐ and intermediate‐level long‐lived radioactive waste at a depth of 500 m in a deep geological disposal, drilled in the Callovo‐Oxfordian claystone (Cox) formation. To do so, a carbon steel casing will be inserted inside disposal cells, which are horizontal tunnels drilled in the Cox. A specific cement grout will be injected between the carbon steel casing and the claystone. A study was conducted to evaluate the possibility of MIC on carbon steel in the foreseeable high radioactive waste disposal. The corrosiveness of various environments was investigated at 50°C and 80°C with or without microorganisms enriched from samples of Andra's underground research laboratory. The monitoring of corrosion during the experiments was ensured using gravimetric method and real‐time corrosion monitoring using sensors based on the measurements of the electrical resistance. The corrosion data were completed with microbiological analyses including cultural and molecular characterizations.

Failure analysis of a natural gas transmission X60 steel pipeline

“…Figure 2(e)–(f) presents the corrosion morphology of the corrosion point after removing surface rust. It can be seen that the cracks between “C” and “D” regions around the corrosion point in Figure 2(f), Figure 2(g)–(h) show an enriched content of S (S:4.1%) by EDS analysis, which is similar to the description in Diler et al (2020) and Xu et al (2008).…”

“…The corrosion inside the steel pipe was principally caused by water accumulation (Xu et al , 2008; Werner, 1998). With the gradual evaporation of water present, the concentration of various corrosive ions would gradually increase (Diler et al , 2020; Werner, 1998). The steel pipe may pit (corrode) particularly rapidly in a humid environment containing halogen ions (such as chloride and bromide ions) or in the presence of specific microorganisms, such as SRB.…”

Potential influence of microorganisms on the corrosion of the carbon steel in the French high‐level long‐lived nuclear waste disposal context at 50°C

“…Description and examples of applications under immersed and buried conditions are given elsewhere. [ 26,27 ] This method is limited to uniform corrosion. However, in the presence of localized corrosion, propagation information can be obtained.…”

“…Schematic cross‐section view of the high‐level long‐lived radioactive waste French disposal concept [ 2 ] . [Color figure can be viewed at wileyonlinelibrary.com]…”

“…In addition to balancing the acidic transient, the alkalinity provided by the MREA might favor the passivity of steel casing, that is, strongly reducing the corrosion rate. [ 2,23–25 ]…”