Water Storage Tank
Definition - What does Water Storage Tank mean?
A water storage tank is a container for storage of water for domestic and industrial uses. Water storage tanks are available in many shapes and sizes. They can be vertical, horizontal, underground and potable, and can be made from plastic, steel, fiberglass, stone or concrete. Water tank leakage and corrosion as well as bacterial growth are threats to the tank.
Over the course of years, tank systems weaken or become damaged if corrosion is not controlled. Uncontrolled corrosion results in holes or possible structural failure of the tank, leading to the release of stored liquids into the environment.
Corrosionpedia explains Water Storage Tank
A water storage tank is a reservoir to store water for industrial, home use and firefighting. Tanks made from steel have the potential to corrode and leak if not properly protected internally from water containing chlorine and externally from soil.
In steel water tanks, corrosion occurs due to current passing from one point to another on the tank's inner surface. The tank wall acts as an anode, whereas the water acts as a cathode. The anode loses electrons, thereby corroding the tank. If left untreated, this can cause water discoloration and leaks from the tank wall.
Factors which accelerate corrosion in water tanks include:
- Tank’s interaction with interconnected components
- Corrosiveness of environment
- Stray electric currents' effects
Corrosion of water storage tanks can be prevented with the use of coatings or linings and cathodic protection. The coating of a tank's inner wall acts as a physical barrier between the wall and water. As a result, it prevents the electrons' loss from the anodic wall. In cathodic protection, electrical currents are supplied from outside the tank to counterbalance the corrosion process in the tank. It inhibits electron flow from the tank walls into the water, and thereby ceases corrosion. Corrosion of the tank's inner wall can also be controlled using corrosion-resistant materials and inhibiting chemicals in stored substances.