Corrosion of Iron by Sulfate-Reducing Bacteria: New Views of an Old Problem

Abstract

About a century ago, researchers first recognized a connection between the activity of environmental microorganisms and cases of anaerobic iron corrosion. Since then, such microbially influenced corrosion (MIC) has gained prominence and its technical and economic implications are now widely recognized. Under anoxic conditions (e.g., in oil and gas pipelines), sulfate-reducing bacteria (SRB) are commonly considered the main culprits of MIC. This perception largely stems from three recurrent observations. First, anoxic sulfate-rich environments (e.g., anoxic seawater) are particularly corrosive. Second, SRB and their characteristic corrosion product iron sulfide are ubiquitously associated with anaerobic corrosion damage, and third, no other physiological group produces comparably severe corrosion damage in laboratory-grown pure cultures. However, there remain many open questions as to the underlying mechanisms and their relative contributions to corrosion. On the one hand, SRB damage iron constructions indirectly through a corrosive chemical agent, hydrogen sulfide, formed by the organisms as a dissimilatory product from sulfate reduction with organic compounds or hydrogen ("chemical microbially influenced corrosion"; CMIC). On the other hand, certain SRB can also attack iron via withdrawal of electrons ("electrical microbially influenced corrosion"; EMIC), viz., directly by metabolic coupling. Corrosion of iron by SRB is typically associated with the formation of iron sulfides (FeS) which, paradoxically, may reduce corrosion in some cases while they increase it in others. This brief review traces the historical twists in the perception of SRB-induced corrosion, considering the presently most plausible explanations as well as possible early misconceptions in the understanding of severe corrosion in anoxic, sulfate-rich environments. E ver since its first production roughly 4,000 years ago, iron has played a central role in human society due to its excellent mechanical properties and the abundance of its ores. Today, iron is used in much larger quantities than any other metallic material (1) and is indispensable in infrastructure, transportation, and manufacturing. A major drawback is the susceptibility of iron to corrosion. Corrosion of iron and other metals causes enormous economic damage. Across all industrial sectors, the inferred costs of metal corrosion have been estimated to range between 2% and 3% of gross domestic product (GDP) in developed countries (2, 3). These costs are to a large extent caused by corrosion of iron, due to its abundant use and particular susceptibility to oxidative damage. Estimates of the costs attributable to biocorrosion of iron lack a computed basis so that they vary widely, and definite numbers cannot be given with certainty. Still, microbially influenced corrosion (MIC) probably accounts for a significant fraction of the total costs (4-7), and, due to its effects on important infrastructure in the energy industry (such as oil and gas pipelines), costs in the range of billions of...

Enhanced microbial electrosynthesis by using defined co-cultures

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“…В останні роки з'явилися дані, що корозійна агресивність різних родів сульфатвідновлювальних бактерій дуже варіабельна і може бути у представників одного роду від високої до практично невираженої та залежить від індивідуальних особливостей штаму [4,5]. Зважаючи на зазначене вище, метою цієї роботи було вивчення метаболічної та корозійної активності сульфатвідновлювальних бактерій, виділених із різних екотопів.…”

Comparison of the microbial community composition of pristine rock cores and technical influenced well fluids from the Ketzin pilot site for CO2 storage

“…Many industries employing buried pipelines and interred structures made a great effort on study the microbial induced corrosion (Iverson 1987;Ford and Mitchell 1990;Lavania et al 2011;Enning and Garrelfs 2014), where SRB play an important role (Crombie et al 1980;Pankhania 1988;Lee et al 1995;Hao et al 1996). Moreover, recent investigations showed that SRB rapidly and massively change the injectivity in the near well bore area Zettlitzer et al 2010).…”