A Forward Osmosis (FO) is an osmotic process that is the natural phenomenon of the transport of water molecules across a semi-permeable membrane in response to a difference in solute concentrations (osmotic pressures) on either side of the semi-permeable membrane. The RO (Reverse Osmosis) process uses hydraulic pressure as the driving force for separation, which serves to counteract the osmotic pressure gradient that would otherwise favour water flux from the permeate to the feed. Hence significantly more energy is required for reverse osmosis compared to forward osmosis.
Related Definitions in the Project: The Process Engineering
