Inhibition effect of thiobacillus denitrificans on the corrosion of X70 pipeline steel caused by sulfate-reducing bacteria in crude petroleum

Although there are many reports demonstrating that thiobacillus denitrificans (TDN) may inhibit corrosion caused by sulfate-reducing bacteria (SRB), very little is known for the inhibition effect in crude petroleum. In this work, the inhibition effect of TDN on the corrosion of X70 pipeline steel caused by SRB in crude petroleum was studied. The optimum incubation condition of TDN was obtained by orthogonal experimentation. The growth characteristics of TDN and SRB in crude petroleum were reflected via analyzing the transformation of sulfur. The inhibition effect on corrosion of X70 pipeline steel in crude petroleum was analyzed by an X-ray energy dispersive spectrometer in conjunction with weight loss measurement. The results suggested that TDN could effectively inhibit SRB-involved corrosion by biologically oxidizing sulfide to sulfate in crude petroleum.