Marine Corrosion of Steel with Aerobic and Anaerobic Biofilms under Changeable Nutrient Concentration Conditions

A diffusional model of marine corrosion wear for steel structures is developed and presented in this work, based on the assumption that long-term corrosion depends on both aerobic and anaerobic bacterial activity, which is connected with nutrient changes. This activity of bacteria biofilms is quantitatively evaluated and verified, based on observed data of hydraulic structures of Far East of Russia. It is shown that any short-term increases of nutrients and anthropological pollutant concentrations may significantly accelerate the corrosion rate. Results show that the influence of anaerobic biofilms on the corrosion rate acceleration of immersed steel structures is underestimated.