Performance enhancement of a basin solar still using γ-Al2O3 nanoparticles and a mixer: an experimental approach

Lack of potable water around the world has become a global problem. Solar stills are one of the main technologies for freshwater production. The performance of these stills can be enhanced by applying nanoparticles in the water. In this research, γ-Al2O3 nanoparticles have been used as an effective approach for pure water production in a single slope basin solar still in the presence of mixer. The nanoparticles were synthesized and verified using FTIR, XRD and SEM analyses. The effects of the amount of γ-Al2O3 nanoparticles, initial water depth, the solar energy intensity and the presence of mixer on the distillate yield, water depth and the temperatures of glass, bottom and brine have been investigated. The results showed that 0.3 mass% of γ-Al2O3 increased the distillate yield by about 60.03%. Due to more water evaporation in experiments with γ-Al2O3, the water depth reduction is more than the experiments without addition of nanoparticles. The increase in glass, bottom and brine temperatures were more significant in tests with nanoparticles. Presence of mixer in the basin uniformly dispersed the nanoparticles throughout the still and increased the evaporation rate and finally the distillate yield. In general, applying γ-Al2O3 nanoparticles enhanced the performance of still due to improving the thermal characteristics of saline water.