MICROBIAL CONTRIBUTIONS TO THE MARINE CORROSION OF STEEL PILING

This study has been undertaken to investigate the phenomenon of the low water corrosion of steel piling in a marine environment. On-site monitoring of corrosion rates has been carried out by zero-resistance ammetry. The averaged rates calculated from these measurements (up to 0.1 mm/year) were significantly lower than the corrosion rates (up to 3 mm/year) found in practice. Several parameters have been considered as factors leading to such a high level of corrosion. In order to assess the involvement of a microbiological component, laboratory investigations, using electrochemical techniques, have been carried out to determine the impact of microorganisms isolated from the biofilms developed on surfaces of piles on the corrosion of steel. The results demonstrated involvement of biofilms in deterioration of piling and the influence of the composition of biofilm consortia on the corrosion rates of steel.