Desalination Process of removing soluble salts (see Sodium Chloride) from Water to render it suitable for drinking, irrigation, or industrial uses. In Distillation< /A>, salt water is Heated in one container to make the water evaporate, leaving the salt behind. The desalinated vapor (see States Of Matter) is then condensed to form water in a separate container. The high fuel costs involved in vaporizing salt water can be reduced by using a Vacuum to lower the Boiling Point or by exposing a water spray or film to high heat, a process known as flash distillation. In Hawaii the vacuum method also produces Electricity in a process that vaporizes warmer, near-surface water, uses the steam to run a Turbine, and condenses the steam with cold water from the ocean depths. Other desalination techniques include electrodialysis, the use of porous membranes to filter out negatively and positively Chargeed salt Ions; freezing, based on the principle that water excludes salt when it Crystallizes to ice; ion-exchange, in which water p asses through a bed of specially treated synthetic Resins that are capable of extracting ions of the salt from the solution and replacing them with ions that form water; and reverse Osmosis, in which Pressure, generated by the presence of salt in the water, forces water through a membrane permeable only by pure water. Osmosis is being used on Catalina Island in California.