The whole process runs at low temperature, which is very important for product quality.
Process efficiency needs to be improved through production of more suitable membranes with improved diffusional characteristics.
The effective, environmentally friendly handling of the diluted osmotic medium is still a problem
to be faced.
The suggested use of evaporation would negatively affect the operational cost of the
process.
An alternative, such as electrodialysis, could provide a solution, but it needs to be carefully evaluated in terms of efficiency and economics.
In addition, the osmotic flux values should be increased, by carefully changing the diffusional characteristics of the membranes and producing more suitable membranes.
A preliminary evaluation of the two kinds of purely osmotic membrane processes, direct osmosis and
osmotic or membrane distillation, reveals certain advantages of direct osmosis.
Such advantages include substantially cheaper membranes and a longer life cycle of direct osmosis membranes
compared to hydrophobic membranes of osmotic or membrane distillation.