Microbiologically Influenced Corrosion (MIC) of Ductile Iron Pipes in Soils

Abstract

Corrosion of ductile cast iron in soils containing iron-oxidizing bacteria (IOB), sulfur-oxidizing bacteria (SOB), iron bacteria (IB), and sulfate-reducing bacteria (SRB), or both, was studied in the laboratory by applying electrochemical techniques such as EIS and corrosion potential measurement. Weight loss measurements were directly correlated to the EIS measurements, thereby establishing a good correlation to estimate the general corrosion rates from the EIS measurements. EIS technique provided information on the nature of corrosion processes involved in MIC phenomena.