Effect of the Aerobic Bacteria Pseudomonas and Vibrio on Cathodic Protection

摘要

Cathodic protection is a widely adopted method of corrosion prevention of steel structures in aqueous and soil environments. When cathodic protection is applied, the electrochemical changes on the metallic surface influence the chemistry of the water and favour the settlement of fouling organisms. In the present study, fresh water species of Pseudomonas and Vibrio were selected to investigate the effect of the species attached to a metal surface on the current demand during cathodic protection at various potentials from -700 to -1200 mV vs Saturated Calomel Electrode (SCE). The amount of current required for maintaining the protective potential was appreciably lower in the presence of these two species. But at protective potentials negative to -1000 mV, there was no significant reduction in current demand. It clearly indicates that microbial depolarisation must also be considered when the system is under cathodic protection at more negative potentials.