The current study explores microbiologically influenced corrosion (MIC) of carbon steel API 5L X65 with and without the presence of sulfate-reducing bacteria (SRB) in CO2 environments. The Electrochemical Impedance Spectroscopy (EIS), potentiodynamic polarisation and Field Emission Scanning Electron Microscopy (FESEM) techniques were employed to analyse the carbon steel’s corrosion behaviour. The Rp values from the EIS signify lower values denoting the steel’s greater corrosion rate. FESEM micrographs found a uniform corrosion on specimens without SRB whereas a pitting corrosion on specimens with SRB. The study concludes that SRB accelerate the corrosion progression due to MIC.
Keywords: CO2 environments; oil and gas; pipeline corrosion; surface morphology