Design, Fabrication, and Analysis of the Performance of Cascade Solar Water Sweetening Accompanied with Latent Heat Thermal Energy Storage System Using Glauber Salt

In this paper, a cascade solar water sweetening still with the capability of installing latent heat thermal energy storage system (LHTESS) was fabricated, and the Glauber salt as a phase change material (PCM) was used in the thermal reservoir for thermal energy storage. Application of weir on the cascade edge leads to force water flow on the absorption sheet and increases the residence time in the apparatus. Thermal performance of the still with (LHTESS) and without thermal energy storage system (WLHTESS) were analyzed at different days. Results showed that the amount of sweet water productivity in WLHTESS is higher than that of LHTESS at the sunny days. However, after the sunset, the amount of produced sweet water in the LHTESS is considerably greater than of the WLHTESS. Furthermore, results showed that increasing the flow rate of sour water from 50 to 150 ml/min for the WLHTESS decreased the sweet water production from 423 to 252 ml/m2 day and for LHTESS from 396 to 235 ml/m2 day.