Augmentation of solar still performance using flash evaporation

A new design of a stepped solar desalination system with flashing chamber is experimentally investigated. The main objective of the investigation was to study the performance of step-wise water basin coupled with a spray water system by augmenting desalination productivity through using two air heaters. The effect of using the spray system for seawater is investigated experimentally at different velocities of the water spray's holder and flow rates on the performance of the solar still in a previous work by El-Zahaby et al. [1]. In the present work, the effect of the inlet sea water temperature and the power consumed by the two air heaters (at both 100 and 250 rpm and water flow rates 3.635, 4.0 and 9.333 l/h) on the performance of the proposed solar system are investigated. It is found that the productivity and performance of the system are significantly positive dependent on both inlet sea water temperature and the power consumed. They decrease with the increase of inlet impure water temperature. At 250 rpm the productivity and efficiency increase with the power consumed to a certain limit after which they begin to decrease gradually while at 100 rpm the productivity and also the efficiency decrease with the power consumed gradually.