Corrosive Water

Enormous quantities of water are required to industrial development for cooling of products and equipment, for process needs, for boiler feed, and for sanitary and potable water. Water use in the United States in 2010 was estimated to be about 355 billion gallons per day (Bgal/d).

Water possesses several unique properties, one being its ability to dissolve to some degree every substance occurring on the earth's crust and in the atmosphere. Because of this solvent property, water typically contains a variety of impurities. These impurities are a source of potential trouble through deposition of the impurities in water lines, in boiler tubes, and on products which are contacted by the water. Dissolved oxygen, the principal gas present in water, is responsible for the need for costly replacement of piping and equipment as a result of its corrosive attack on metals with which it comes in contact.

Corrosive water can dissolve high concentrations of copper from pipes and fixtures. Copper can cause bluish-green stains in sinks and a metallic taste to water, especially with water in contact with pipes for several hours (overnight). Corrosive water can also dissolve lead from solders joining copper pipes or occasionally from lead pipes. While most corrosive water problems occur with metal plumbing systems.

Corrosion of plastic PVC plumbing components is also possible resulting in dangerous amounts of vinyl chloride in drinking water. This usually only occurs when inferior plastic pipe that was not approved for drinking water systems has been used. Approved plastic pipe is directly stamped with a "NSF" (National Sanitation Foundation) seal on the side.

When purification and water-conditioning techniques are practiced in order to produce water that is acceptable for home or industrial use, certain analytical tests must be performed to ensure that the objectives of treatment are being achieved.