Cathodic Protection

Cathodic Protection (CP) is a potent electro-chemical method utilized to manage the corrosion of a metal surface by making it function solely as the cathode of an electrochemical cell.   

Corrosion (oxidation) takes place only at the anode, so converting the entire structure into a cathode stops metal erosion. This is accomplished through two main methods:

Sacrificial Anode CP: Connecting the target structure (e.g., a pipeline) to a more active metal (like zinc or magnesium). The active metal acts as the sacrificial anode, preferentially corroding to supply protective electrons.

Impressed Current CP (ICCP): Using an external DC power source (rectifier) to drive current from inert anodes through the electrolyte (soil/water) to the structure, forcing its potential into the safe, negative (cathodic) range.