Evaluation of a Pilot Saline Water Treatment Unit using a Solar-Thermal Concentrator with Zero Energy Cost for Arid Regions

This work compares the performance of a solar still during winter and summer months for purification of salty water, suiting arid conditions to produce distilled water. To ensure zero energy cost, the apparatus is completely run on ambient solar energy pipes for water circulation and heating, without any pumping requirement. The performance of the unit is evaluated over daylight hours under standard operating conditions during summer where sunshine is almost at its peak. However, the design of the solar still is modified to enhance the heating rate inside the solar basin during winter months with low ambient temperature through the attachment of a solar pipe warm water circulation into the water basin, which was fed by solar panel system water heating units. The water circulation from the basin to the solar collectors is solely due to the temperature difference and no pumping is required to increase the flow of water. The modified arrangement was found to achieve a temperature inside the water basin of over 50°C on a typical winter day when the ambient temperature was as low as 9°C. This resulted in the maximum amount of produced condensate yield reaching up to 2 l/hr, which was found to exceed the typical yield of 1.5 l/hr under summer conditions.

Keywords:

Water Treatment , Wastewater , Clean Energy , Water Reuse , arid region