The key technology in the word for Seawater desalination process is Reverse Osmosis.
In this process seawater is forced against semi-permeable membranes under pressure in a continuous flow condition. The high salt content of seawater requires that the operating pressure for Reverse Osmosis must be between 60-65 bar. As the water permeates through the membrane most of the dissolved impurities are removed and 99.5% of the total salt is removed. The impurities are left behind in the flowing water and the concentrated stream from the membranes is discharged to the sea. The design of the complete system must optimize the flows, the area of the membranes, and other conditions to keep the system operating at the highest efficiency possible.