Effect of absorber coating on the performance of a solar still in the region of Ouargla (Algeria)

As the world's population grows in number and riches, the demands for water and energy are increasing faster than ever. Reports on the availability of potable water have listed Algeria among top countries affected by water shortage. This work provides a study dealing with distillation for isolated low-density population areas using solar energy. The utmost objective of the present investigation is to enhance the yield of a solar still by improving the performance of its absorber. This was achieved by laminating the surface of the absorber by layers of treated alluvial sand. Small-scale solar-powered distillation pilot units have been set up and operated. The tests were conducted in Ouargla, south of Algeria. Two series of experiments were performed. The first consisted of studying the effect of the sand diameter on the daily output of the still. The influence of the sand surface density was investigated in the second series. The experimental results showed that: For a fixed mass of sand (given surface density), the yield improvement of the still was inversely proportional to the sand particle diameters. The output in distilled water for a fixed particle diameter increases with the increase in the sand surface density.