A cathode is the negatively charged electrode in an electrochemical cell that attracts electrons. It is a component of batteries along with the positively charged anode. One of the concerns of trenchless construction is the longevity of pipes and how corrosion and decay can be prevented. Cathodic protection is sometimes used in pipelines to prevent corrosion.
Trenchlesspedia Explains Cathode
In an electrolytic cell, the two electrodes – cathode and anode – have different functions and properties. Cathodes attract electrons and anodes repel them, creating the flow and discharge of electrons from anode to cathode. These properties cause anodes to decay and cathodes to gain mass. The use of an electric charge to prevent pipeline decay is the idea behind cathodic protection.
To prevent decay, a DC current flow is supplied between a pipeline and other metal surfaces, where the pipeline plays the role of a cathode. This involves the development of either a galvanic cell or an impressed current cell. In a galvanic cell, the anode is sacrificial, because it is giving up electrons, while in an impressed current cell an electron source is interposed between the two. Such methods have proved useful in the preservation of pipeline infrastructure. Trenchless construction is often used in the rehabilitation of decayed pipes.