After a hurricane in the 1960s caused salt water from the Atlantic Ocean to seep into private wells-effectively destroying the drinking water-Kill Devil Hills in Dare County, N.C., took action. Today, four water treatment facilities provide safe, clean and healthy fresh water for residents and tourists.
Two technologies currently are used by Dare County for the treatment of water. The first is a conventional ion exchange method that softens well water. The second is a reverse osmosis (RO) procedure that desalts brackish groundwater from wells drilled down 300 to 400 feet.
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Sensors and Analyzers Prove Instrumental in Preserving Civil War Sub: Recovered Submarine Requires Chloride Removal to Prevent Rust and Corrosion
The following interview is with Robert Huehmer, who currently is process manager with USFilter?s (a Vivendi Water company) Memcor, Microfloc and General Filter products division, located in Timonium, Md.
The when, where and how treatment is applied.
Demand for a cheaper way to transform saltwater into fresh has spurred the development of a new technology by AquaSonics International, Inc., the Rapid Spray Distillation (RSD) process, that desalinates water at a fraction of the cost of current methods.
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At Work on Groundwater Treatment
Three French companies are meeting the water demands of large populations through the use of seawater desalination.Distillation and reverse osmosis are two competing techniques in the desalination of seawater. While each method has pros and cons, both provide a vital service in making seawater drinkable. Three French water companies (Saur, Degremont and Sidem) are working to improve the quality of fresh water created by both these methods and have invested heavily in the Mediterranean and Middle East markets with these technologies.
Las Palmas, Spain
Desalination technology has brought fresh water and hence industrial and commercial development to areas of the world that otherwise might have remained unproductive. Not only has development been enhanced by this technology but, more importantly, the health and welfare of many people have been improved by the supply of sanitary fresh water supplies.
Once considered a viable technology only for desalination, membrane processes are increasingly employed for removal of bacteria and other microorganisms, particulate material and natural organic material that can impart color, tastes and odors to the water.
Though both the cation and the anion resin are responsible for the quality of a deionization (DI) system effluent, it is the cation resin that is the big contributor to leakage. Improving the leakage characteristics of DI cation will reduce effluent conductivity, drop the pH and ultimately lead to better silica performance from the system.
Off the coast of Washington, 32 families on Guemes Island were faced with an aging well that was drawing salt water into its system. Because groundwater is scarce on the island, residents had to rely on what little rain water soaks into the ground.