Design, Construction and Experimental Study of a Solar Still for Brackish Water Purification under Djiboutian Climate

Abstract

A single sloped solar still were designed and fabricated to operate under Djibouti city weather condition during the period April-May 2019. In this study, a single slope solar still has been constructed from materials available on the local market. Series of experiments were carried out on solar still using brackish water. Ambient temperature, water temperature in basin, absorber plate temperature, glass cover temperature and vapor temperature were measured along with the hourly water production. This study has revelead that the vapor temperature is always above that the others temperatures for all the four days of experiments. Then, the effect of water amount in the basin on productivity of solar still was investigated using different amount of water 6 L, 8 L, 10 L and 12 L. The experimental results show that the total accumulated distillate output for the single slope solar still is 2490 mL, 2390 mL, 2240 mL and 2015 mL, respectively. However, it is observed that with increase in basin water amount distillate water production decreases. On the other hand, the effect of wind speed on the daily productivity of solar still is evaluated. Experimental investigations show that the cumulative productivity increases when the wind speed average increase. Finally, water quality analyses were conducted before and after the experiments. The average analysis results obtained showed a removal efficiency of 98.16%, 98.42%, 97.43% and 95.39% for TDS, electrical conductivity, hardness water and chloride, respectively. It was also observed that data obtained of the product water were within the normal range prescribed by World Health Organization (WHO) standards.