Prediction of long-term localized corrosion rates in a carbon steel cooling water system is enhanced by metagenome analysis

• Published in: Engineering failure analysis Vol. 141; p. 106733
• Main Authors: Gősi, Péter, Rátkai, Sándor, Shetty, Prateek, Wirth, Roland, Maróti, Gergely, Oszvald, Ferenc, Knisz, Judit
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2022
• Subjects: Carbon steel; Emergency cooling water pipeline; Mechanical engineering; Microbiologically influenced corrosion; Molecular microbiological methods; Sulphate reducing bacteria, methanogens, ageing management; Sulphate reducing bacteria, methanogens, ageing management; Microbiologically influenced corrosion; Carbon steel; Emergency cooling water pipeline; Molecular microbiological methods; Mechanical engineering
• ISSN: 1350-6307; 1873-1961
• DOI: 10.1016/j.engfailanal.2022.106733

[Display omitted] •Prediction of MIC-affected corrosion rate in a carbon steel cooling water system.•Visual inspections, metagenomics, evaluation of field test results were used.•An empirical model based on field tests and published data was developed.•Empirical models and metagenomics are useful in ageing management activities. To predict variation of maximum localized penetration with exposure time, long-term localized corrosion was assessed in an emergency cooling water system composed of two carbon steel pipelines of 700 mm diameter transporting raw river water at flow velocities of 1 m/s and 0.1 m/s. Field tests, visual inspection, ultrasonic testing, BART testing, SEM-EDS and metagenomic analyses were performed to assess the progress of long-term corrosion and determine the influence of microbes in the corrosion process. High corrosion was linked to sulphate reducing bacteria and potentially to methanogenic archaea in the low-velocity pipeline, while moderate corrosion was linked to non-sulphate reducing bacteria in the higher velocity pipeline. Using historical and literature data available as well as our own test results, an empirical model was developed to predict Maximum Localized Penetration change over time to be applied in the ageing management of cooling water systems. Molecular Microbiological Methods in combination with traditional techniques are useful tools in the ageing management of pipelines. By applying the empirical model developed and the approach presented, unexpected through-wall leaking can be avoided, thus, saving costs and assets.