Biologically competitive effect of Desulfovibrio desulfurican and Pseudomonas stutzeri on corrosion of X80 pipeline steel in the Shenyang soil solution.

In this paper, we have investigated the corrosion mechanism of X80 carbon steel in the presence of nitrate reducing bacteria (NRB), sulfate reducing bacteria (SRB) or both in the Shenyang soil solution. The results show that both SRB and NRB increase the corrosion rate of steel specimens and cause pitting corrosion of steel. Electrochemical tests and weight-loss data show that the addition of NRB in the SRB-containing environment leads to the reduction of corrosion. The thermodynamic analyses confirm the competitive advantage of NRB for the nutrients (organic carbon sources and irons) and the chemical oxidation of ferrous sulfide by nitrite, which results in a mitigation in the microbiologically influence corrosion (MIC) of SRB.