Desalination plant integrated with solar thermal energy: A case study for the Brazilian semi-arid

The present work proposes a stand-alone process for brackish water thermal desalination for the Brazilian semi-arid (BSA) region. The Multi-Effect Distillation (MED) is coupled with solar collectors, a thermal energy storage (TES) system, a biodigester for electricity generation and a brine reject valorization scheme. The TES provides the continuous production of freshwater using solar energy alone, unlike other studies in the literature. The brine recycling affords lower amounts of brine reject than that reported in the literature for MED plants. A detailed cash-flow analysis estimates the economic feasibility of the plant and a water sales price of US$ 4.95/m³ for a plant with a capacity of 72 m3/day. The results indicate that thermal desalination is a cost-effective and sustainable alternative to mitigate the water shortage in the BSA region.