Role of Microorganisms in Corrosion Induction and Prevention

Microbiologically-influenced corrosion (MIC) is defined as the deterioration of metals as a result of metabolic activities of microbes. The biological harmful activities modify local chemistry and render it more corrosive to the metal. The aerobic iron and manganese bacteria are mainly responsible about the accelerated pitting attacks of stainless steel, however the anaerobic sulfate reducing bacteria (SRB) are responsible for most highly corrosion damages to offshore steel structures. Most MIC takes the form of pits that form below the colonies of living organic matter and mineral and the deposits of biological origin. Stainless and carbon steel tanks, pipelines, heat exchangers, fuel storage tanks are mainly affected by MIC. On the other hand, other beneficial microorganisms play a major role for protecting these surfaces from corrosion via different mechanisms including biofilms formation. The aim of this review is to present a spotlight on the history and the role of microorganisms on the induction and prevention of corrosion. This includes corrosion inhibition mechanisms employing beneficial microorganisms with special reference to microbial biofilms to avoid the dramatic economic loss due to corrosion. On the contrary, different types of harmful microorganisms included in corrosion are also discussed including iron and sulfur reducing bacteria. Review Article Mansour and Elshafei; BBJ, 14(3): 1-11, 2016; Article no.BBJ.27049 2