Effect of Iron Bacteria on Corrosion Behavior of J55 Steel

Iron bacteria were enriched from an oilfield drilling waste in northern Shaanxi, Stoke medium and CGY medium were sued to screen, separatie and purify the baceria, a pure iron bacteria strain was obtained. Weight loss method, electrochemical test and scanning electron microscopy (SEM) were used to study the effect of iron bacteria strain on corrosion behavior of J55 steel. The results showed that the iron bacteria strain had typical prussian blue positive reaction. Weight loss method showed that the effect of iron bacteria on corrosion rate of J55 steel decreased and then increased; polarization curves and electrochemical impedance spectroscopy (EIS) results showed that corrosion current density of the sample first decreased and then increased, ac impedance first increased and then decreased. SEM showed that a dense corrosion product film formed on electrode surface.