ABSTRACT

Desalination processes have been instrumental in improving water quality for over a century. Two general processes predominate the technology that is in use: Thermally Driven Processes and Pressure-Driven Processes. Beginning with thermal processes of simple design, modern state of the art has produced many variations, including multi-stage flash evaporation, multiple-effect distillation and vapor compression evaporation. The fastest growing desalination process is reverse osmosis, which comprises nearly 30% of the world capacity. As of the inventory taken, there were 11,066 desalting plants installed producing more than 5.4 billion gallons per day of water. Undoubtedly due to the widespread use of desalination in the Middle East, the use of seawater for a feed source enjoys the broadest usage in the world. New advances in reverse osmosis technology have the promise of reducing both capital and operating cost for the process. It is believed that improvements will continue that will allow construction of small systems to become an economically viable choice.