Desalination

Desalination History -1852: British patent on desalination device Process that removes dissolved minerals (including but not limited to salt) from seawater and المالحة brackish water History -1852: British patent on desalination device -1928: First major commitment to desalination -1938: First large-scale desalination plant (Saudi Arabia) -WWII: Considerable desalination research by US (establishment of Office of Saline Water (OSW) and Office of Water Research

Simplified Box Diagram for Desalination Feedwater (seawater or brackish water)

World Desalination Capacity by Source of Water (June 1999)

Diagram of a Vapor Still

Major Desalting Processes Thermal: -Multi-stage flash distillation -Multiple-effect distillation -Vapor compression Membrane: -Electrodialysis -Reverse osmosis Minor processes: freezing, membrane distillation, solar humidification

Boiling Temperature of Water at Different Pressures Pressure (bar) Temperature (deg. C) 2 120 1 100 0.25 65 0.1 45

Multi-stage flash distillation

Components of a Reverse Osmosis Plant

Reverse Osmosis