BACTERIAL ADHERENCE ON A POLYMERIC COATING APPLIED ON CARBON STEEL

MONICA ZAPPONI; PABLO CASTRO; SANDRA G. GOMEZ DE SARAVIA; MAURO BANERA; SANDRO NICOLINO ; VERÓNICA RODRIGUEZ BAUZADA; SILVIA E. RASTELLI; ALEJANDRO R. DI SARLI; SONIA BRUNO; MARISA R. VIERA; CECILIA I. ELSNER

CABA

Congreso; 4° Congreso de Integridad y Corrosión en la Industria del Petróleo y el gas; 2021

IAPG (Instituto Argentino del Petróleo y del Gas)

Microbial contamination in the oil and gas industry results in a variety of problems in drilling fluids, hydraulic fracturing fluids, water flooding, pipelines, and storage tanks. Microorganisms such as sulfate-reducing bacteria (SRB), acid producing bacteria, and/or other halophiles can negatively impact asset integrity and reduce the quality and quantity of produced hydrocarbons. Organic coatings are used on the internal tube surface to prevent corrosion problems in service. The aim of this study was to evaluate the performance of a polymeric coating applied on carbon steel in the presence of a microbial consortium from an oil storage tank. The samples were exposed to a batch culture of the microbial community in Postgate´s C medium in anaerobic conditions at 28 ± 2 °C for 60 days. After that time, different techniques were applied to analyze surface deterioration: Scanning Electron Microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), Epifluorescence Microscopy (EM). Furthermore, the planktonic and sessile microbial communities were analyzed by Next-Generation Sequencing (NGS) of 16S rRNA gene. The genetic analysis showed a shift in the bacterial community along the experiment. SRB were predominant at the beginning, diminishing their number with time. Bacteria belonging to the Desulfovibrionales and Bacterioidales orders were the most abundant in the biofilms formed on the samples. According to the EIS results, neither deterioration of the coating, nor corrosion of the carbon steel was detected after the exposure to the cultures for 60 days.