ABSTRACT
Spacers form an integral part of membrane modules, as they promote turbulence, which enhances mass transfer. It is argued that fouling is a spacer problem even more so than it is a membrane problem. In the last decade or so, much work has been done on improving the antifouling behavior of spacers. This includes various forms of surface modification including antimicrobial coatings and surface treatments. The choice of spacer geometry also plays an important role in tackling polarization as well as foulant accumulation although a big portion of the work on novel spacer geometries has been limited to computational studies. Three-dimensional printing is a promising technique to produce spacers with optimal feed flow properties and fouling propensity. The discussion leads to the benefits of applying conductive spacers and recent advances in the same, especially for control of fouling and related phenomena. The chapter ends with spacer-based in situ fouling characterization techniques.
