A Review of the State-of-the-art in Reverse Osmosis Antifouling Approaches.

Membrane based water purification systems, such as reverse osmosis (RO), offer the potential advantages of lower mass, power and volume than the current state-of-the-art. However, membranes are subject to fouling. Fouling is the deposit if solids, bacteria and adsorbed organics on the membrane surface. Fouling reduces the flix of water across the membrane and drives up mass, power, and volume requirements. As a result, fouling control is required to realize the potential benefits of membrane systems. On Earth, there is a reliance on the use of membrane cleaners to address fouling. However, for spaceflight applications the need to resupply cleaning chemicals creates a high resupply penalty. As a result, NASA has been evaluating different approaches to address membrane fouling that do not increase equivalent system mass prohibitively (ESM). This paper provides a summary of current conventional membrane fouling control strategies and identifies several new promising approaches currently being developed with support from NASA.