Efficient Solar Desalination System Using Humidification/Dehumidification Process

Abstract

An innovative solar desalination system is successfully designed, manufactured, and experimentally tested at Makkah, 21.4 degN. The system consists of 1.15 m2 flatplate collector as a heat source and a desalination unit. The unit is about 400 l vertical cylindrical insulated tank. It includes storage, evaporator, and condenser of hot saltwater that is fed from the collector. The heated water in the collector is raised naturally to the unit bottom at which it is used as storage. A high pressure pump is used to inject the water vertically up through 1mm three nozzles inside the unit. The hot saltwater is atomized inside the unit where the produced vapor is condensed on the inner surfaces of the unit outer walls to outside. The system was experimentally tested under different weather conditions. It is obtained that the system can produce about 9 l a day per quadratic meter of collector surface area. By that it can produce about 1.6 l/kWh of solar energy. Moreover, the water temperature has a great effect on the system performance although the scaling possibility is becoming significant. By that way the cost of a liter water production is relatively high and is obtained as 0.5 US$.