THERMAL PROCESSES
Distillation, a thermal process that includes heating, evaporation, and condensation, is the oldest and most widely used of desalination technologies. Modern methods for the distillation of large quantities of salt water rely on the fact that the boiling temperature of water is lowered as air pressure drops, significantly reducing the amount of energy needed to vaporize the water. Systems that utilize this principle include multistage flash distillation, multiple-effect distillation, and vapour-compression distillation.
Multistage flash distillation plants account for more than half of the world production of desalted water. The process is carried out in a series of closed ... (100 of 8,179 words)