Corrosion Behavior of L360N Pipeline Steel Under Action ofSulfate-Reducing Bacteria in Produced Water of a Shale Gas Field

Taking three kinds of separator produced water of the gathering and transportation pipeline in a shale gas field containing 10³,10⁵,10 sulfate-reducing bacteria (SRB) per 1 mL water sample (named as 1^#, 2^#, 3^# water sample) as the test medium, the corrosion behavior of L360N pipeline steel immersed in different water samples for 14 d was studied. The results show that the more SRB in the water sample, the higher the corrosion rate, and the more serious the corrosion of pipeline steel. After immersing in 1^# water sample for 14 d, the surface of pipeline steel contained FeS, and the high concentration of HCO₃^- contributed to the formation of corrosion product film. After immersing in 2^# water sample, the content of FeS on the surface of pipeline steel was the highest, and the corrosion products distributed in uneven clusters; high concentration Cl^- and low concentration HCO₃^- together accelerated the damage of the film layer. After immersing in 3^# water sample, the surface of pipeline steel was relatively smooth with few corrosion products and the lowest corrosion degree.