Basin-type solar still productivity enhancement using porous materials and changing the glass cover geometry

Water resource reduction is the major threat of many countries in recent decade. Solar desalination is a promising method for production of healthy water. However its low productivity is the main reason for not using it publicly. The main aim of this study is productivity enhancement of single slope basin-type solar still using of porous materials and changing the glass cover geometry. The absorber plate was shiny when the water was poured on it, although it was covered with matte black color. This would cause to some of the incident solar beams reflected from the absorber surface, leading to decreasing its absorptance. So, as first change, the absorber surface was covered with porous mineral pumice. Decreasing the reflection is the main reason for using them. In fact, solar beams were trapped inside the pores of these materials. Also, they provide additional surface for water evaporation. It was observed that porous material could increase 20% of productivity. According to our previous work, it seems that vapor condensation rate is the key parameter that limits the distilled water production rate. Changing the glass cover geometry, in a way that provide further surface for vapor condensation, was increased the productivity up to about 10%.