Fraunhofer ISE develops solar thermally driven compact desalination systems based on membrane distillation for a capacity range between 100 and 500 L/d and larger system capacities up to 10 m³/d. A modular design of systems is important in order to resize them to a wide range of user profiles. Membrane distillation (MD) is a separation technique which combines a thermally driven distillation process with a membrane separation process. The thermal energy is used for phase changing of liquid water into vapor. Unlike membranes for reverse osmosis (RO), which have a pore diameter in the range of 0.1 to 3.5 nm, membranes for MD generally have a pore diameter of 0.1- 0.4 m. The separation effect of these polymer membranes is based on their hydrophobic nature. Apart from some experimental systems, the MD-technique has not been used for desalination up to now, but, for implementation of solar-driven stand-alone desalination systems, it holds important advantages. The article describes two developed types of solar-driven MD system and discusses their installation and economic performance. The full article first appeared in the November/December 2008 issue of D&WR magazine
Fraunhofer ISE develops solar thermally driven compact desalination systems based on membrane distillation for a capacity range between 100 and 500 L/d and larger system capacities up to 10 m³/d. A modular design of systems is important in order to resize them to a wide range of user profiles.
Membrane distillation (MD) is a separation technique which combines a thermally driven distillation process with a membrane separation process. The thermal energy is used for phase changing of liquid water into vapor.
Unlike membranes for reverse osmosis (RO), which have a pore diameter in the range of 0.1 to 3.5 nm, membranes for MD generally have a pore diameter of 0.1- 0.4 µm. The separation effect of these polymer membranes is based on their hydrophobic nature.
Apart from some experimental systems, the MD-technique has not been used for desalination up to now, but, for implementation of solar-driven stand-alone desalination systems, it holds important advantages.
The article describes two developed types of solar-driven MD system and discusses their installation and economic performance.
The full article first appeared in the November/December 2008 issue of D&WR magazine