title: Corrosion of low carbon steel by microorganisms from the 'pigging' operation debris in water injection pipelines.
abstract: Present in all environments, microorganisms develop biofilms adjacent to the metallic structures creating corrosion conditions which may cause production failures that are of great economic impact to the industry. The most common practice in the oil and gas industry to annihilate these biofilms is the mechanical cleaning known as "pigging". In the present work, microorganisms from the "pigging" operation debris are tested biologically and electrochemically to analyse their effect on the corrosion of carbon steel. Results in the presence of bacteria display the formation of black corrosion products allegedly FeS and a sudden increase (more than 400mV) of the corrosion potential of electrode immersed in artificial seawater or in field water (produced water mixed with aquifer seawater). Impedance tests provided information about the mechanisms of the interface carbon steel/bacteria depending on the medium used: mass transfer limitation in artificial seawater was observed whereas that in field water was only charge transfer phenomenon. Denaturing Gradient Gel Electrophoresis (DGGE) results proved that bacterial diversity decreased when cultivating the debris in the media used and suggested that the bacteria involved in the whole set of results are mainly sulphate reducing bacteria (SRB) and some other bacteria that make part of the taxonomic order Clostridiales.
authors.affiliation: Laboratoire de Génie Chimique, CNRS, Université de Toulouse, 4 Allée Emile Monso, 31432 Toulouse, France. Electronic address: ccotecoy@ensiacet.fr.
authors.forename: Claudia
authors.initials: C
authors.lastname: Cote
authors.affiliation: Laboratoire de Génie Chimique, CNRS, Université de Toulouse, 4 Allée Emile Monso, 31432 Toulouse, France.
authors.forename: Omar
authors.initials: O
authors.lastname: Rosas
authors.affiliation: School of Pharmacy and Biomedical Sciences, University of Portsmouth, St. Michael's Building, White Swan Road, PO1 2DT Portsmouth, UK.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Sztyler
authors.affiliation: School of Pharmacy and Biomedical Sciences, University of Portsmouth, St. Michael's Building, White Swan Road, PO1 2DT Portsmouth, UK.
authors.forename: Jemimah
authors.initials: J
authors.lastname: Doma
authors.affiliation: School of Pharmacy and Biomedical Sciences, University of Portsmouth, St. Michael's Building, White Swan Road, PO1 2DT Portsmouth, UK.
authors.forename: Iwona
authors.initials: I
authors.lastname: Beech
authors.affiliation: Laboratoire de Génie Chimique, CNRS, Université de Toulouse, 4 Allée Emile Monso, 31432 Toulouse, France. Electronic address: regine.basseguy@ensiacet.fr.
authors.forename: Régine
authors.initials: R
authors.lastname: Basseguy
mesh_terms: D001419:Bacteria / Q000302:isolation & purification; D018407:Bacterial Physiological Phenomena; D018441:Biofilms / Q000254:growth & development; D002244:Carbon / Q000737:chemistry*; D003343:Corrosion; D058645:Denaturing Gradient Gel Electrophoresis; D058266:Dielectric Spectroscopy; D012623:Seawater / Q000382:microbiology*; D013232:Steel / Q000737:chemistry*
chemical_list: D013232:Steel; D002244:Carbon
keywords: Anaerobic biocorrosion; Electrochemical impedance spectroscopy; Gel electrophoresis; Low carbon steel; Pigging debris