With the seeming rapid depletion of potable water on Earth, nations are scrambling for viable water sources to resolve the growing severity of the problem. The U.S. state of California, for one, has turned to the largest body of water, the Pacific Ocean, for the key to end the state’s progressive struggle with drought.
The Golden State’s extreme drought is now on its fourth year, according to NBC News, and so far, much of the state’s hopes lie in how to turn the vast amounts of seawater into drinking water. This fall, the Poseidon Water in Carlsbad, San Diego, will provide around 50 million gallons of water to Californian communities. This is reportedly the largest desalination plant in the West Coast, costing more than $1 billion to build. This is not the first desalination plant in the state, though. In the modest town of Sand City, a desalination facility is already on its fifth year of operations.
The Use of Reverse Osmosis
Desalination is a water filtration technique that uses the reverse osmosis process to convert saltwater into purified drinking water. The RO process is basically the opposite of the natural osmosis procedure. Normal osmosis process involves getting the solvent to move through a membrane from low concentrated solution to an area of high solute concentration, refining water or equalizing solute concentrations.
Reverse osmosis is just the opposite by applying external pressure so that the solvent can seep through from high solute concentration to low concentration. Reverse osmosis filter has been used to purify saltwater, for instance, by removing salt from the water molecules.
In desalination process, gallons of saltwater are brought into giant tanks that apply great osmotic pressure to move the salt-concentrated solute through the membrane for treatment. The amount of pressure also depends on the salinity of the substance, in which case 99% of salts (and other effluent materials) in the concentration, must be removed to finally deliver clean, drinking water from the source.
The RO method is already being used to filter water effectively for use in many residential communities. Renowned water treatment manufacturers like AXEON Water Technologies offer an effective reverse osmosis filtration system with separate components for purifying residential tap water. Officials of Santa Barbara near Carlsbad, are also reportedly considering reviving a desalination plant that had once been built but never used due to the return of rains.
Tapping the Pacific: Desalination Plant Will Make Ocean Drinkable. Nbcnews.com. Jun 11, 2015.
Tapping the oceans. Economist.com