What process involves using low voltage current to concentrate corrosion on a sacrificial anode in a water tank?

The process that involves using low voltage current to concentrate corrosion on a sacrificial anode in a water tank is cathodic protection. This technique is designed to prevent corrosion of metal surfaces that are submerged or in contact with water. In cathodic protection, a sacrificial anode (a more reactive metal) is connected to the metal structure that needs protection. When a low voltage current is applied, it causes the sacrificial anode to corrode in place of the protected structure, effectively drawing corrosion to the anode and away from the tank itself. This method is particularly useful in maintaining the longevity of water tanks and pipelines by reducing the risk of metal degradation.

In contrast, electrolysis refers to the process of driving a chemical reaction using electric current, which can be related but is not the specific application mentioned in the question. Filtration is a physical separation process used to remove particles from liquids or gases and does not involve electrical currents. Flocculation is a chemical process that involves the aggregation of particles into flocs and is typically used in water treatment processes rather than for corrosion protection.