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Water Facts Ocean water is about 3X as salty as human blood brackish watersalt water

Dec 28, 2015



  • Water Facts

  • Ocean water is about 3X as salty as human bloodbrackish watersalt water

  • Why is the ocean salty?Water is evaporated from the ocean surface but the salt is too heavy to be evaporated and remains in the sea.water cycle, also known as the hydrologic cycle

  • Why cant humans drink salt water?Too much salt sends your metabolism into crisis. From every cell, water molecules rush off like so many voluntary firemen to try to dilute and carry off the sudden intake of salt.Cells become dehydrated (short of the water they need to carry out their normal functions May lead to seizures, unconsciousness, and brain damage). Overworked blood cells carry the salt to the kidneys, which eventually become overwhelmed and shut down. Without functioning kidneys you die.

  • Over 13,000 desalination plants worldwide Producing more than 12 billion gallons of water a day. Only 0.2 percent of global water consumption Desalination market is expected to expand 9.5% CPGR next 10 years.

    Source: Desalination

  • Popular Desalination MethodsMulti-Stage DistillationReverse OsmosisIon Concentration Polarization

  • Multi-Stage Flash DistillationVapor Compression DistillationReverse OsmosisIon Concentration PolarizationProcessSeawater heated; flows thru successively lower pressure containers; vapor condensed on tubes of heat exchanges into fresh waterMechanical compressor or a steam jet compressor generates heat for evaporation. Feed water added and partially evaporates; vapor condenses into freshwaterHigh pressure forces water molecules through a membrane leaving larger molecules of salts and minerals behindIon concentration polarization zone (ion depletion zone) generated in a microfluidic channel AdvantagesCan use lower quality feedwater than ROEconomies of scale in capital costs Simple, reliable Ideal for small operations such as resorts Higher recovery rate Less energy intensiveMicrochip size; 8 inch size can produce 15 L water per hour Light bulb energyDis-advantagesExtremely energy intensiveExtremely energy intensive Not efficient for larger scale Greater sensitivity to poor quality feedwaterNew technology not yet commercialized

  • Source: American Membrane Technology Association Costs

  • Environmental Concerns About Desalination

    Ecological effects resulting from the disposal of brine from the desalination process;

    Entrainment of aquatic species in and around the desalination facility intake; and

    Enormous energy requirements