Enhanced solar desalination units

摘要

The vast majority of water on the Earth's surface, over 96%, is saline water present in the oceans. In some areas there is not sufficient fresh water to provide people the water they need. Thus, there is a need to desalinate salt water. The basin-type solar still is known to be the most simple and economic method for water desalination. This study investigates how to enhance the productivity of the basin-type solar still. Basin-type solar stills with a basin area of 1 m(2) are used in the study. Two means are used for enhancing its productivity: integrating the solar still to a solar water heater (SWH) to preheat the feed water to the still, and using some metals as energy storage media. A maximum hourly productivity of 400 and 900 ml were recorded for stills without and with SWH, respectively. Copper filings (CF), iron filings (IF) and iron swarf are used as energy storage materials. An increase of 36.2% in still productivity is noticed when adding 1 kg of CF to the still. Comparing copper with iron, it is noticed that the productivity of the CF still is 34.1% higher than that of the IF still.