What Does Saline Water Mean?
Saline water is water that contains high concentrations of dissolved salts. The concentration of salt in water is expressed as parts per million (ppm). This means that water with a dissolved salts concentration of 10,000 has 1% weight contributed by the salt content.
Though saline water is widely associated with the ocean, it can be found almost anywhere, such as groundwater. Saline water tends to be corrosive, so appropriate treatments should be performed to reduce its corrosive effects.
Corrosionpedia Explains Saline Water
Metals undergo corrosion when electrons are donated by or taken from compounds such as other metals. In this case, the metal atoms carry a charge and undergo dissolution in water. The process is more efficient if the water also conducts electricity so that the electrons can be taken from both near and far sources. Saline water has better conductivity than fresh water.
Thus, when some metals build compounds using materials that are dissolved in water, the surface layer is protected from further reactions. This makes the metal corrode much faster, leading to potential damage.
In order to prevent this from happening, certain factors from the water are regulated, such as oxygen availability, temperature as well as chloride content. This can be regulated through water treatments and other procedures that reduce the corrosiveness of water.
The use of sacrificial anodes, such as other metals like aluminum, is also preferred to provide corrosion protection to equipment, materials and other structures that are exposed to saline water.