Setting up of a cost-effective continuous desalination plant based on coupling solar and geothermal energy

Abstract

The aim of the work was to describe and test a solar desalination system for salt and brackish water desalination considering a real application, in order to provide detailed technical features of a future plant based on the calculated data by the modelling approach. The main innovative aspect of the studied solar desalination system consists in reproducing, in a restricted environment, the water cycle that commonly occurs in nature. The process is a thermal distillation process based on a first humidification phase and a second phase of air dehumidification, exploiting, at steady-state conditions, only solar thermal energy, and it is capable to work 24 h day−1. It is built with materials that are commonly used in the building sector, reducing construction costs. The findings have led to a system easily integrable in real scale scenarios to recover fresh water from a solution of salt or brackish water, for both potable uses and process uses. Thanks to these technological solutions, a low specific energy consumption (5.5 kWh m−3 of water) is obtained, envisaging lower running cost.