Combining Forward Osmosis with Reverse Osmosis

A combination of forward osmosis with reverse osmosis could facilitate the treatment of some high fouling wastewaters. The system uses brine to draw water from the wastewater without high pressure or turbulence. Key element is the membrane’s ability to allow rapid passage of water without much internal concentration polarization. The diluted draw solution can then be desalinated by reverse osmosis. The Two-Way Osmosis or TWO system may also be usable in very remote areas, where seawater ponds can be built for evaporative recovery of salt. Catalyx is designing a pilot system (patent pending) to desalinate seawater without external electric power. This article was published in the May/June 2009 issue of Desalination & Water Reuse.

A combination of forward osmosis with reverse osmosis could facilitate the treatment of some high fouling wastewaters. The system uses brine to draw water from the wastewater without high pressure or turbulence. Key element is the membrane’s ability to allow rapid passage of water without much internal concentration polarization. The diluted draw solution can then be desalinated by reverse osmosis.

The Two-Way Osmosis or TWO system may also be usable in very remote areas, where seawater ponds can be built for evaporative recovery of salt. Catalyx is designing a pilot system (patent pending) to desalinate seawater without external electric power.

This article was published in the May/June 2009 issue of Desalination & Water Reuse.