Solar Thermal Desalination Plant: Simulation and Performance Optimization

Safe drinking water for all is an ambitious goal that will not be achieved without resorting to non-conventional desalination technologies. This sixth Sustainable Development Goal will be one of the most important human challenges in the next decades. Thermal desalination processes combined with solar thermal energy could contribute in finding solutions to freshwater scarcity, particularly in the Middle East and North Africa. This paper proposes a simulation model for a multi-effect desalination plant driven by solar energy. Hence, we contribute in solving the problem of shortage of fresh water, while avoiding the consumption of fossil fuel and the environmental impact caused by CO2 emissions. Numerical models are developed based on energy and mass conservation equations. It concerns solar collectors and a multi-effect desalination plant. Numerical simulation is performed to optimize and enhance the overall performance of the considered system. Additionally, an energetic assessment has been also performed in order to analyze the performance parameters on the average daily distillate production. Then, current system has been simulated over a whole year using meteorological data of Gabes (Southern of Tunisia) in order to evaluate the solar operation of the desalination plant. The results show that additionally, the highest direct normal irradiation (DNI) levels increase the thermal performance ratio of the multi-effect desalination plant. The results of this study can be beneficial in determining the appropriate operation mode for a multi-effect desalination plant coupled with parabolic trough collectors.