Performance Analysis of Successive Evaporation Condensation Solar Still (SECSS) Desalination Unit with Heat Recovery

Water scarcity is one of the most critical challenges in many developing countries in Middle East. Seawater desalination techniques those rely on solar energy are promising solutions in Egypt where long coasts and high solar intensities are available. The present research aims at designing and fabricating a mobile desalination unit that relies on successive evaporation-condensation stages with localized condensation heat recovery. This unit is driven by solar energy or other waste heat sources, while the evaporation will be enhanced using wicks, and the condensate will be collected in between aluminum sheets aligned in front of the wicks. The multi-stages of evaporation-condensation processes lead to high efficiency production of fresh water. The presented model is considered one of the passive techniques that does not need electricity. The evaporation can be achieved passively with the capillary effect in the wicks, hence, the availability of the unit in small to medium scale makes it easier to be adopted in rural areas far from the grid. A prototype for laboratory was built of 3 stages to validate the theoretical modeling and a very good agreement was obtained. A maximum production rate of 5.2 L/m
²
hr was attained using 10 stages simulation. Using parallel arrangement leads to better production rate since the more frames in series the lower the production rate per stage. The model can be extended to predict the production rate for various configurations and operating conditions leading to an optimum design for large scale units.