Principal Factors Affecting Microbiologically Influenced Corrosion of Carbon Steel

Abstract

Laboratory-scale batch experiments (semicontinuously fed) were conducted using a two-level factorial experimental design to investigate principal factors and interactions affecting microbiologically influenced corrosion (MIC) of carbon (C) steel. Factors considered included the C source as chemical oxygen demand (COD), sulfate (SO 4 2-) concentration, calcium carbonate (CaCO 3 ) precipitation, and bacteria inoculation at 20°C. Yates' algorithm was applied to calculate main and interaction effects, and an empirical model indicating major trends was obtained. Experimental results showed CaCO 3 precipitation played a significant role in influencing the biocorrosion tendency of steel. In the supersaturated condition, SO 4 2concentration and bacterial inoculation had no appreciable effects on corrosion. In the undersaturated condition, the corrosion rate was affected significantly by SO 4 2concentration and bacterial inoculation. The effect of each factor on corrosion rate was explored.

Microbial activity involvement on soil corrosion of ductile iron – Electrochemical & microscopic study

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The influence of Desulfovibrio vulgaris on the efficiency of imidazoline as a corrosion inhibitor on low-carbon steel in seawater

“…The biocorrosion process may be detected by a combination of observations: corrosion morphology, presence of microbial slime masses, presence of hydrogen sulphide and ferrous or ferric hydroxide as observed in anaerobic systems [6]. This process is of considerable concern because the sulphate-reducing activity of bacteria is thought to be responsible for >75% of the corrosion in productive oil wells and for >50% of the failures in buried pipelines [7].…”

Anticorrosive Influence of Acetobacter aceti Biofilms on Carbon Steel

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