Historical Landmarks in Desalination
These brief highlights attempt to put the development of desalination in a historical perspective. Because there is often a period of time between the generation of an idea and the appearance of the concept either in print or in operable equipment, the dates necessarily lack precision. Many people have contributed to the development of the art; only a few can be mentioned.
Antiquity – Need for water aboard ships, particularly military vessels, which were not in a good position to resupply at the nearest port. One technique used was to suspend sheepskins over water during the evening; the water which condensed was wrung out in the morning. This constituted a crude sort of solar distillation. There are reports of hollow balls of clay or wax being submerged in the sea. The water found inside the balls was sometimes fresh, indicating a very early reverse osmosis. The inconsistent results showed that the materials and technology were not under control. Municipal needs were supplied by locating the cities near a good source of water or, in Roman times, by building aqueducts, many of which still remain.
Middle Ages – Distillation as a separation process was a common practice among alchemists. This was a single stage, single effect process. It was rarely, if ever, used to produce drinking water.
1791 – Secretary of State Thomas Jefferson issued a document explaining distillation to supply water aboard ships.
1843 – Norbert Rillieux was issued US patent nos. 3,237 in 1843 and 4,879 in 1846 for what amounts to multi-effect distillation and distillation under vacuum, used for concentrating sugar in syrup rather than producing drinking water.
1872 – A large scale solar distillation plant was built in Chile to supply drinking water for miners. Because the modest intensity of solar radiation causes such plants to require a large area, this technology has not been widely used. In a typical location, a solar still might produce 2.3 liters per square meter.
1930s – Development of synthetic ion-exchange materials (beads). Logistics of regenerant supply prevent use of ion exchange for desalination of water above a few hundred mg/L of salinity.
1936 – W. F. Langelier developed the calcium carbonate saturation index (LSI) for stabilizing product water to protect downstream distribution systems.
1945 to 1948 – The 19 IDA desalting Plant Inventory lists an 0.086 MGD submerged tube distillation plant in Preston and similar plants 0.031 MGD in West Ham and 0.035 MGD in Birkenhead, UK. All were to supply water for power plants. This technology suffers from a slow release of steam from the outside of the tubes.
1950 – Invention of ion-exchange membranes by Walter Juda and Wayne McRae, covered by US patent. 2,636,851, made electrodialysis practical. Commercialization of electrodialysis by Ionics began shortly after.
1952 to 1982 – Federal funding, P.L. 82-448 et seq., for desalination research, development, and demonstration through Office of Saline Water, initially part of the Bureau of Reclamation, shortly after converted to report directly to the Secretary of Interior, averaged about $30 million per year in 1985 dollars. During this period a number of attempts were made to desalt water by freezing methods. The process was never sufficiently successful for commercialization.
1957 – Thermodynamics of multi-stage flash worked out by Robert Silver. Commercialization began shortly after by Weir-Westgarth, the first large such plant being installed in Kuwait in 1960.
1957 – Work by Reid and Bretton in Florida on water desalination by pressure through films, including cellulose acetate. The thickness of conventional films made the process impractical because of low flux and resulting high driving pressures.
1958 –Model of membrane transport based on irreversible thermodynamics worked out by Ora Kedem and Aharon Katchalsky.
1959 – Asymmetric, or anisotropic, cellulose acetate membrane developed by Sidney Loeb working with Srinivasa Sourirajan at UCLA. Commercialization by a number of companies followed.
1960s – Hollow fine fiber membranes of nylon developed and commercialized by DuPont.
1966 – Desalination journal started under the editorship of Zeeb Pelled. Since his death, shortly after, it continued to this day as a principal source of information in the field with Miriam Balaban, his wife, as editor.
1968 – Spiral wound element developed by Julius Westmoreland (Westmoreland 1968). Commercial elements are now sold in spiral-wound, hollow-fiber, plate-and-frame and tubular configurations.
1970s – Thin film composite membrane developed by John Cadotte. Because of the higher salt rejection and greater flux, this membrane and its offspring, are replacing the older formulations with cellulose acetate.
1971 – A pilot piezodialysis unit was publicly demonstrated. This process, patented a few years before, desalts water by passing an enriched stream of water through a membrane under pressure. Its advantage is that the minor component of the feed water is passed through the membrane. Its disadvantage is that appropriate membranes are difficult to make.
1976 – Reclamation issues RFP for membranes for Yuma Desalting plant, authorized under P.L. 93-320. Seven potential suppliers provided bids: 4 spiral wound RO, 1 hollow fiber RO and two ED. Two from the first group were selected.
1990s – Development of efficient energy recovery for RO and NF concentrate.
1992. P.L. 102-575 authorizes Reclamation to investigate and identify opportunities for reclamation and reuse of municipal,
industrial, domestic, and agricultural wastewater, and naturally impaired ground and surface
waters, for the design and construction of demonstration and permanent facilities under the "Title XVI" Program.
1996 – P.L. 104-298 authorizes Reclamation to support desalination research under the Desalination and Water Purification Research Program.
2001 – DuPont, then the dominant SWRO supplier, abandoned the field without passing the technology to a successor company.
2002 – DewVaporation process developed and tested at Arizona State University under grant from Reclamation’s DWPR program.
2005 – DP3RO adapted from food processing industry to irrigation return flow treatment.
2006 – Electrodialysis Metathesis process developed and tested by University of South Carolina under grant from Reclamation’s DWPR program.
2010 - Secretary of the Interior Ken Salazar launches WaterSMART, which includes Advanced Water Treatment Grants to encourage pilot and demonstration projects to address viability of AWT.