Rotating discs solar still: New mechanism of desalination

The present study introduces a new mechanism of distillation via changing the conventional solar still to modified solar still with rotational discs. The authors aimed to decrease the saline water thickness as much as possible and increase the evaporative surface area of the basin water and the exposure surface area for solar radiation. As a result, two shapes of rotating discs were installed to be investigated inside the solar still; flat and corrugated discs with and without wick material. The performance of the modified solar still with rotating discs has been studied under different rotational speeds for the discs (0.02, 0.05, 0.1, 0.5, 1.0, 2.0, 3.0, and 4.0 rpm). Results revealed that the freshwater distillate of the discs’ distiller was greater than that of the conventional (reference) distiller. Besides, the optimum performance of modified solar still was obtained at 0.05 rpm and 0.1 rpm when integrating the flat and corrugated discs with and without wick, respectively. Moreover, the freshwater distillate of the corrugated discs’ solar still with wick was improved by 124% over the reference distiller. The maximum thermal efficiency was 54.5% and 50% for the corrugated and flat discs’ solar stills with wick, respectively at 0.05 rpm.