Experimental Research and Performance Analysis of an Improved Solar Still with a Solar Concentrator and Heat Recovery Units

A conventional solar still is a simple desalination device with convenient operation. However, the low temperature, the solar light loss caused by condensation droplets, and the latent heat dissipation constrain the performance. Aiming at these weaknesses, this paper proposes an improved solar still with a solar concentrator and heat recovery units. A compound parabolic concentrator with mirror focuses is employed to concentrate the solar radiation and thus promote the evaporation temperature. An air blower is used to enhance the evaporation and avoid the vapor condensation occurring at the top glass. In addition, the latent heat released by the vapor condensation preheats the feed seawater, inducing the latent heat recovery. The results of simulating the concentrator show that the reception angle of the concentrator is 30 degrees. The experimental test under the actual weather indicates that 3 h of light is available for the device placed along the north-south direction without tracking the sun. The yield per hour and the total efficiency of the 3-h outdoor test reach 431 g and 41.14%, respectively, showing a good water production performance of the proposed solar still.