Pitting Depth Prediction Caused by SRB using Empirical Equation

Microbiologically influenced corrosion (MIC) is a serious problem in the oil and gas industry. The most common microorganism responsible for MIC is sulfate-reducing bacteria (SRB) which produces detrimental sulfide ions into the environment. Currently, there are some prediction models that develop to predict corrosion rate caused by SRB. However, among the models, the prediction is limited to predict the general corrosion rate, whereas, SRB caused localized corrosion. Thus, the objective of this work is to predict the pitting depth caused by SRB using available empirical equation. The study showed that the pitting depth increased with the increasing of sulfide concentration. In contrast, the pitting depth decreased with increasing sulfite concentration.  The decreasing of pitting depth is related to the inhibitive FeS film formed, while the increasing of pitting depth is caused by the decreasing of the film thickness in the presence of sulfite.