(100e) Forward and Pressure Retarded Osmosis: Fundamentals and Applications

Engineered Osmosis (EO) is an emerging platform technology that harnesses the power of osmotic pressure to drive water filtration (forward osmosis, FO), power production (pressure retarded osmosis, PRO), and dewatering (direct osmotic concentration, DOC).  The high energy costs of pressure driven membrane separation has fueled interest and development in this rapidly growing area.  Many in the field are considering new configurations of engineered osmosis that address wastewater reuse, food processing, desalination, produced water treatment, disaster relief and waste heat capture and utilization.  Others are focusing primarily on membrane design, which still is the primary obstacle to the commercial viability of this emerging platform technology.  Osmotic flow across membranes is hindered by mass transfer resistances attributed to the anisotropic structure of traditional salt rejecting membranes.  Several groups have found ways to design new membranes to reduce this mass transfer resistance by altering traditional fabrication methods or by developing radically new membrane structures altogether.  In all, these new membranes will enable the unique processes being developed to harness the power of osmosis.