Glass basin solar still with integrated preheated water supply - Theoretical and experimental investigation

Theoretical and experimental investigation is performed in a glass basin solar still. The glass basin solar still is separated into two sections as preheater (lower) and evaporator (upper) by a glass plate. The preheater section contains five rectangular hollow glasses as fins which enhance the heat transfer rate. Also provisions are made to place the energy storing materials (charcoal, sand and metal scrap) in the hollow space of glass fins. The evaporator section contains the saline water to evaporate. The saline water enters in the one end of preheater section and flow around the fins and gets heated. The water that fills the preheater section completely then enters into the evaporator section through a hole at another end. System performance is analyzed by varying the preheater section water depth (2, 4, 6 and 8 cm) with the help of glass pieces. The effect of energy storing materials in fins also investigated. The result shows that the increase in water depth in preheater section reduces the day time productivity but considerably enhances the nocturnal productivity of the glass basin solar still. The presence of charcoal in fins augments the total distillate output of the system up to 3.61 kg/day.