Solar Driven Multi-effect Distillation

Abstract

Potable water supply has a significant role in today's developing world. A number of seawater desalination technologies have been developed during the last several decades to augment the supply of water in arid regions of the world. Due to the constraints of high desalination costs, many countries are unable to afford these technologies as a fresh water resource. It is very important to determine the specifications of desalination systems in order to achieve cheaper water prices and better operational conditions.

The application of the direct steam generation into a solar parabolic trough collector to multi effect distillation is proposed and economically evaluated. The thermal fluid of the solar field is pure water, which boils as circulating along the solar collectors. The steam generated drives a multi effect distillation unit. This solar distillation system is compared with multi effect plants connected to a conventional parabolic trough collector field, and with fossil fuel powered distillation plants.

A special desalinization unit which utilizes solar or waste energy has been developed and tested indoors. In this unit, a relatively large fraction of latent and sensible heat of condensation is successfully recycled and utilized.