Thermodynamic Modelling of an Industrial Scale Solar Desalination Plant with Low-Concentration CPC Collectors and Multiple-Effect Thermal Distillation (MED) in India

Kurzfassung

A solar seawater desalination plant with glass-covered compound parabolic (CPC) collectors, flash evaporation chamber and multiple-effect distillation (MED) with 8 stages, operating in Vallur, India, is modeled in the Ebsilon thermodynamic simulation software. Standard equations from literature for solar collectors and for saltwater heat exchangers are selected and implemented as scripts. Model results are a distillate/steam ratio of 7.0 and average temperature steps of 2.8 K between effects. With the simulations it has been possible to identify performance-relevant deviations of the mass flow in solar field loops and in a saltwater preheater during the trial operation period. It is shown that the implementation of current state-of-the-art equations into the proven modeling software already including physical properties of saltwater and calculation of solar plants with time series provides a viable basis for a digital twin of the commercial plant.