Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4365097 | International Biodeterioration & Biodegradation | 2013 | 9 Pages |
The utilization of high strength carbon steels in oil and gas transportation systems has recently increased. This work investigates microbiologically influenced corrosion (MIC) of API 5L X80 linepipe steel by sulfate reducing bacteria (SRB). The biofilm and pit morphology that developed with time were characterized with field emission scanning electron microscopy (FESEM). In addition, electrochemical impedance spectroscopy (EIS), polarization resistance (Rp) and open circuit potential (OCP) were used to analyze the corrosion behavior. Through circuit modeling, EIS results were used to interpret the physicoelectric interactions between the electrode, biofilm and solution interfaces. The results confirmed that the extensive localized corrosion activity of SRB is due to a formed biofilm and a porous iron sulfide layer on the metal surface. Energy Dispersive Spectroscopy (EDS) revealed the presence of different sulfide and oxide constituents in the corrosion products for the system exposed to SRB.
► 16S rRNA gene sequence indicates mixed bacterial consortium. ► Biofilm revealed different corrosion products in structure and composition. ► Corrosion was severe in the biotic condition compared to the abiotic control. ► Nature of corrosion was localized.