Forward Osmosis (FO)
Reference work entry
In literature, osmotic pressure-driven membrane processes are known as direct osmosis (DO) or forward osmosis (FO). FO dating back to the early 1960s is a membrane contactor process that utilizes osmotic pressure difference (Δπ) across the membrane for water transport through a semipermeable membrane (Cartinella et al. 2006; Cath et al. 2006) than a hydraulic pressure as in RO. The osmotic pressure difference across the membrane arises from the use of concentrated solution called draw solution (DS) on the permeate side of the membrane (Fig. 3a). Apparently FO may be a viable and sustainable alternative to thermal-driven (membrane distillation) and pressure-driven (reverse osmosis) concentrating methods, which are highly energy intensive, hence very expensive. In the presence of natural sources of concentrated DS, e.g., seawater, FO can be very attractive due to its significantly lower energy demand for pumping (Tang et al. 2010). The equation below is generally used to describe water...
- Beaudry EG, Herron JR, Peterson SW (1999) Direct osmosis concentration of waste water: final report. Osmotek, CorvallisGoogle Scholar
- Hydration Technologies Inc. (n.d.) Hydration bags-technology overview: http://www.hydrationtech.com/merchant.mv?Screen=CTGY&StoreCode=MHTI&CategoryCode=TECH-FOGoogle Scholar
- Osmotek Inc. (2003) Landfill leachate treatment http://www.rimnetics.com/osmotek.htm
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