Anodic protection

Specialist expertise for corrosion control in aggressive chemical processes

Unique expertise within Cathec

While cathodic protection is widely known within the corrosion industry, anodic protection is a far more specialised technique mastered by only a limited number of experts. Cathec has developed this unique expertise through many years of practical experience in the design, commissioning, and maintenance of anodic protection systems for chemical process installations and storage tanks.

For certain applications, anodic protection offers significant technical and economic advantages compared with conventional corrosion protection techniques. This makes the technology particularly attractive for the chemical industry, tank terminals, and producers handling aggressive chemicals.

What is anodic protection?

Anodic protection is an electrochemical corrosion protection technique in which the protected metal is deliberately polarised as the anode within a specific potential range where a stable passive layer is formed.

This passive oxide film drastically reduces the corrosion rate of the metal, often to only a fraction of the original rate.

An anodic protection system typically consists of:

• A rectifier / potential controller
• Reference electrodes
• Internal cathodes
• The vessel or tank to be protected (anode)
• The process medium (electrolyte)

System operation is continuously monitored to ensure that the material remains within its safe passive potential range.

Which materials are suitable for anodic protection?

Anodic protection can only be applied to materials with a sufficiently broad and stable passive region. Typical examples include austenitic stainless steels, certain titanium alloys, and specific corrosion-resistant alloys.

Carbon steel is generally less suitable because its passive region can be too limited or unstable for certain applications, increasing the risk of accelerated corrosion or material damage if the system is not correctly designed and controlled. Cathec has developed empirical expertise in assessing the specific applications for which anodic protection is technically feasible.