Thermodynamic and experimental analysis of a solar concentration unit for freshwater production

Abstract

This research investigates the thermodynamic characteristics of solar ponds as industrial-scale freshwater production and solar energy storage systems. The study focuses on a solar pond utilizing saline wastewater as a heat transfer medium. Experimental findings reveal density variations within the wastewater, ranging from 1.09 to 1.27 \(g{cm}^{-3}\), and viscosity ranging from 0.96 to 1.13 \(cP\). Additionally, the wastewater exhibited a heat capacity between 3.163 and 3.142 \(kJ{kg}^{-1}{K}^{-1}\). Operational data indicate peak solar radiation and evaporation rates in June, with a corresponding freshwater production of approximately 5 L per day. Ambient temperature analysis revealed July as the warmest month and January as the coldest. Theoretical temperature predictions aligned closely with experimental observations, with maximum and minimum effluent temperatures occurring in July and December, respectively.