New Understandings of Biocorrosion Mechanisms and their Classifications

Microbes were first associated with corrosion as early as 1910 [1]. However, much confusion remains in biocorrosion mechanisms because their investigation involves multidisciplinary knowledge in several diverse research areas such as bio-electrochemistry, microbiology, corrosion engineering and chemical engineering. Billions of dollars are lost to biocorrosion each year in the US alone [2]. The Alaska pipeline leak that caused a major spike in the world regarding oil prices in the spring of 2006, heightened attentions on biocorrosion. As a consequence of depleting oil reserves and high oil prices, water flooding is more frequently used to increase reservoir pressure. The water used in the operation often introduces nutrients and microbes into the reservoirs. Microbial activities are now major concerns in oil and gas production and transportation. As infrastructures are aging, biocorrosion is becoming more often a risk factor in many industrial operations such as oil and gas transportation, water utilities, and power plant cooling systems. An additional risk factor for oil transportation lines is that pipe wall water-wetting, instead of oil-wetting, is becoming a more common flow condition and this promotes the diversity and growth of microbes, leading to faster pipe failures.