Dynamic modeling and performance of the first cell of a multi-effect distillation plant

•A dynamic model of the first cell of a solar assisted MED plant is developed and discussed.•The model is based on a MED unit erected at Plataforma Solar de Almería.•The cell is made up by an effect and a preheater, both have been modeled.•The model was calibrated and validated with real experiments.•The dynamic model shows a good agreement with measured data.

This paper describes a model to simulate the thermal transient behavior of the first cell of a solar-assisted multi-effect distillation (MED) plant. It has been designed according to the experience with an experimental solar thermal desalination system erected at CIEMAT-Plataforma Solar de Almería (PSA). The non-linear first principles model has been developed using the object-oriented Modelica language. It includes two submodels corresponding to the effect and the preheater of the first cell of the MED plant. Both submodels have been calibrated and validated with experimental data. The numerical predictions show a good agreement with measured data.