Experimental Investigation of a Membrane Distillation Unit Coupled with Solar Energy

Due to the increasing demand and unprecedented pressure, on overexploited water resources in Kairouan, the production of freshwater from unconventional sources (brackish water, impaired water) becomes necessary. Solar distillation is a promising method of providing freshwater from saltwater and brackish water. This work presents an experimental study of a spiral module, membrane distillation unit (MD) coupled with solar water collector. The study is made up of three circuits: The first circuit is a saltwater filling circuit, the second circuit consists of an MD module, and the third circuit is distilled water. The MD unit operates by a photovoltaic module. The system is a research and development cooperation project between the Tunisian LASEM Laboratory and the Fraunhofer Institute for Solar Energy Solar membrane distillation for resource-efficient desalination in remote areas. The effect of solar irradiation influences the temperature of the feed chamber, the flow of hot water through the feed chamber on the membrane side, and the heat exchanger which works with the external heat source, which varies between 60 and 83 °C. The hot vapor flow on the membrane side is cooled by the cold water intake in the condensation chamber on the membrane side. The results obtained can be detected at a high productivity of 18.6 l/h.