About Desalination

Overview of Desalination

Desalination is any process that removes salts from a variety of sources, including: seawater, brackish (water that is saltier than fresh water), river, and brine (water that is nearly saturated with salt). With improvements in technology, desalination processes are becoming cost-competitive with other methods of producing usable water for our growing needs. Desalination of ocean water is common in the Middle East because of water scarcity, and is growing fast in the USA, North Africa, Spain, Australia and China. It is used also on ships, submarines and islands with limited sources of fresh water.

 

Over 40 years ago, John F. Kennedy stated:

"If we could ever competitively, at a cheap rate, get fresh water from saltwater,....
(this) would be in the long range interests of humanity which would really
dwarf any other scientific accomplishment."

 

With limited freshwater supplies and technological advances in converting saltwater to freshwater, desalination is becoming a viable, and cost-effective water supply alternative for communities around the world and in the United States.

 

History of Desalination

Desalination is not a new technology. In 1790, United States Secretary of State Thomas Jefferson received a request to sell the government a distillation method to convert salt water to fresh water.

During World War II, it was felt that desalination should be developed to convert saline water into potable water, where fresh water supplies were limited. In 1952 Congress passed “The Saline Water Act” to provide federal support for desalination. The U.S. Department of the Interior, through the Office of Saline Water (OSW) provided funding during the 1950s and 60s for initial development of desalination technology, and for construction of demonstration plants.

One of the first seawater desalination demonstration plants to be built in the United States was at Freeport, Texas in 1961. Dow, in cooperation with the U.S. Department of the Interior, built a 1 million gallons per day (mgd) long tube vertical distillation (LTV) plant at a cost of $1.2 million, that produced water for the City of Freeport and for Dow operations. During the dedication ceremony for the desalination plant, President Kennedy said, “No water resources program is of greater long-range importance than our efforts to convert water from the world’s greatest and cheapest natural resources – our oceans – into water fit for our homes and industry. Such a break-through would end bitter struggles between neighbors, states and nations.”