Design and performance improvement of a solar desalination system by using solar air heater: Experimental and theoretical approach

This paper focuses on the design and performance improvement of a recently developed solar humidification-dehumidification (HDH) desalination system comprising centrifugal air blower, humidification chamber equipped with two electric water heaters (500 W each) and a condenser. To improve the design and performance of this desalination system, a solar air heater was used before the humidification chamber to pre-heat the induced ambient air. Two sets of experiments (I and II) were performed in January 2015 under the similar ambient conditions for all the test days in Madinah (24° 28′ 06″ N, 39° 36′ 51″ E), Saudi Arabia. Experiment set-I was performed without solar air heater and with two electric water heaters whereas experiment set-II was performed with solar air heater and one electric water heater. The results show that daily productivity and Gained Output Ratio (GOR) significantly increased in experiment set-II compared to experiment set-I whereas the Specific Energy Consumption (SEC) and cost per liter of fresh water produced in experiment set-II was greatly reduced compared to that of experiment set-I for the studied range of induced air flow rates.