Experimental Validation of a Solar Powered Multistage Flash Desalination Unit with Alternate Storage Tanks

Abstract

The fossil fuels that power conventional desalination systems cause substantial environmental impact. Solar desalination can satisfy critical water needs with only a minimal contribution to global warming. The current work presents an attractive new design suitable for regions with limited water resources and high solar radiation rates. This work is an experimental study of a newly designed, solar-powered, multi-stage flash (MSF) desalination plant. The design could address the need to increase the limited water resources in solar energy-rich areas. The prototype consists of a solar collector, an MSF unit, and a novel dual thermal storage tank design. In this prototype, preheated brine is directly heated by circulation through the solar collector. Two tanks serve the MSF unit; one tank feeds the MSF unit while the other receives the preheated feed water. The two tanks alternate roles every 24 h. The study was conducted in Taif, Saudi Arabia, throughout the month of September 2020. The results of the experiment showed that 1.92 square meters of solar collector area is needed for an average daily production of 19.7 kg of fresh water, at a cost of approximately $0.015 per liter.