Subsurface intakes

Subsurface intake -Conventional -Spiral-wound modules -Remineralization... 

Subsurface Intakes Subsurface (beach well) intakes are widely used for small and medium-size seawater desalination plants. Beach wells are typically located on the seashore, in close vicinity to the ocean. Beach well intakes include vertical or horizontal wells and associated intake pumping and electrical components. The subsurface intake... 

The largest SWRO plant in North America, which obtains source water fiom beach wells, is the 15,000-m /day water supply facility for the Pemex Salina Cruz refinery in Mexico. This plant also has the largest existing seawater intake wells—three Raimey-type horizontal collectors with capacities of 15,000 m /day each. Key considerations for the selection of the type of intake most suitable for the site-specific conditions of a given SWRO plant and guidelines for the development of subsurface intakes for seawater desalination plants are discussed elsewhere (AWWA, 2007 Wright and Missimer, 1997 Voutchkov, 2004a). 

Building enclosure integrity with regard to weather and physical intrusion are important to investigate in all areas, on all sides, and on roof and subsurface extensions, including tunnels and utility routes and entry points into buildings. Locations of air intakes for mechanical and natural ventilation and locations and conditions of storage elements for chemicals and other hazardous materials are important to analyze. 

While the survey vessel is underway, subsurface water is pumped to the instrumentation using a diaphragm pump from an intake positioned approximately 1 m below the surface to avoid turbulence created by boat wash. Trials of the system have shown that it can be successfully used from vessels as small as 4 m, and depending on which instruments are deployed, data acquired at speeds of 25 knots or more. 

The seawater intake facilities are among the key components of every SWRO plant. Adequate and consistent flow and quality of source water over the entire useful life of the plant must be assured. The source water collection system for SWRO desalination plants could be an open-ocean intake or subsurface (beach well) intakes. 

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