Study on Biofilm Forming Microorganisms Associated with the Biocorrosion of X80 Pipeline Steel in Produced Water from Oilfield

Abstract

Abstract Biocorrosion is the main process that causes pipeline damages and losses in the oil industry. The objective of this work was to investigate the influence of biofilm forming microorganisms on the biocorrosion of X80 steel exposed in produced water through microbiological characterization, film and biofilm analysis by optical microscopy and scanning electron microscopy, weight loss and surface analysis by laser confocal microscopy. Changes in produced water after 360 days were attributed to planktonic cells, temperature conditions, contact with air, photo-oxidation, biodegradation, and seasonality. The total aerobic bacteria presented sessile cell concentration of 7.39 x 104 CFU/cm2, while the other investigated groups showed lower concentrations. The micrography of the film showed salt crystals, whereas in the biofilm microorganisms, exopolysaccharides and corrosion products were observed. Weight loss after 360 days for the abiotic and biotic systems was 0.0222 g/cm2 and 0.3039 g/cm2, respectively, showing that microorganisms accentuated the corrosion of X80 steel.

Keywords

• Biocorrosion
• biofilm
• pipeline
• produced water
• X80 steel