Autonomous Solar HDH Seawater Desalination
Abstract
The solar-driven humidification-dehumidification (HDH) cycle is a type of solar thermal distillation technology that works based on the vapor absorption properties of air combining an evaporation process (humidification) with a condensation process (dehumidification). The design of the system allows the integration in pilot units of small and medium size adjusted to the final needs of fresh potable water and with the possibility of relying only on solar energy. This paper describes an HDH solar unit designed and constructed in Portugal in the framework of project SELFWATER. A MATLAB model based on energy and mass balance equations in the evaporator and condenser was developed and the results are compared with preliminary experimental tests performed in the constructed prototype at LNEG thermal desalination test facility. This comparison shows a good agreement between the model and the test results mainly in terms of the Gain Operating Ratio (GOR) and Performance Rate (PR) following also the results of similar devices taken from a literature review.
Keywords
Desalination, Humidification, Dehumidification, Solar energy, Small-scale water production.