The Impact of Cross Flow Velocity On Optimal Forward Osmosis Membrane Design and Performance

For the last 25 years Hydration Technology Innovations (HTI) has pioneered the design and development of novel membranes and engineering solutions in the field of Forward Osmosis (FO). FO membrane performance is governed by the solute permeability coefficient of the membrane active layer (B), the membrane permeability constant (A) and the membrane structural parameter (S-parameter). Optimal FO membrane design involves minimizing the ‘S-parameter’ by minimizing membrane thickness and tortuosity while maximizing membrane porosity. In addition to its asymmetric FO membrane based on Cellulose Triacetate (CTA), this past year HTI has developed and commercialized a high water flux Thin Film Composite (TFC) FO membrane. This TFC membrane gives HTI the versatility to design a new line of FO products needed to treat different streams of wastewater across a wide pH range. In testing FO membranes, operating conditions such as temperature, pressure, draw solution composition and concentration and flow rate play very critical roles in properly capturing true membrane performance. This presentation will focus on work done to investigate the impact of Cross Flow Velocity (CFV) on optimal FO membrane design and performance of both HTI’s CTA and TFC membranes.