Cathodic protection of carbon steel using zinc and magnesium as sacrificial anodes in different conductivity solutions

Abstract

Abstract This work investigated the cathodic protection of carbon steel in different conductivity solutions using sacrificial anodes of zinc and magnesium. The effect of salt concentration (0.5–3.5% NaCl), the distance between structure and anode, and the area ratio of anode to cathodic on the protection efficiency was investigated and discussed. The consumption rate of sacrificial zinc and magnesium was evaluated for a range of operating conditions. High cathodic protection efficiency was obtained by Zn with low consumption rate compared to Mg. The Mg showed short lifespan and high potential shift to more positive and high protection current decrease after short time of applying the protection. Therefore, zinc is a successful sacrificial anode while magnesium is not recommended for long term protection for the range of salt concentrations investigated.