Effect of Iron Oxidizing Bacteria Biofilm on Corrosion Inhibition of Imidazoline Derivative in CO2-Containing Oilfield Produced Water with Organic Carbon Source Starvation

In this work, corrosion of a Q235 carbon steel in CO2-containing oilfield produced water in the presence of iron oxidizing bacteria (IOB) with organic carbon source starvation and the inhibiting performance of imidazoline derivative were investigated by weight loss, electrochemical measurements and surface analysis techniques. Results show that iron oxidizing bacteria (IOB) could survive well in the aqueous environments with organic carbon source starvation. Corrosion of the steel occurred under the IOB biofilm. Both the planktonic and sessile IOB cell counts after 14 days of testing were related to the biofilm incubation time. The corrosion rate of the steel covered with 7-day IOB biofilm was lowest suggesting that this biofilm had the weakest corrosivity in the test solution. The inhibition performance of the inhibitor was affected by the IOB biofilm formed on steel surface. There was a higher inhibition efficiency of the inhibitor, when the steel was covered with a 2-day IOB biofilm due to less IOB biofilm formed on the steel. (c) 2018 The Electrochemical Society.