Cathodic protection on stuctures of carbon steel using sacrificial anode methode for corrosion control

Abstract

The pipes for land or sea are generally made of carbon steel and susceptible to corrosion. Cathodic protection can be used to control metal corrosion in water and soil. Cathodic protection is a metal surface protection system bypassing adequate direct current to the metal surface and converting sacrificial anode area on the metal surface into cathodic region. The aim of this research was to study the effect of cathodic protection in controlling the corrosion rate of carbon steel and determine the best immersing time for sacrificial anode in 25,000 ppm sodium chloride solution to protect the cathode. Zinc was used as the sacrificial anodes for the cathodic protection. Then, the effect of immersion time (10, 20, and 30 days) and distance of the anode from the cathode (1, 2, and 3 cm) were investigated. The best protection for corrosion was obtained at immersion time of 10 days and electrode distance of 1 cm, allowing corrosion rate of 0.694 mpy with an efficiency of 81.8%.