Membrane Fouling Control in Treatment of Seawater Reverse Osmosis On Membrane Distillation

Membrane distillation (MD) is a based thermal process, in which only vapor molecules transport through porous hydrophobic membranes. Its system has big advantage comparig with reverse osmosis(RO) in desalination.  The advantages of MD include (1) lower operating temperatures range than multistage flash(MSF) and multieffect distillation(MED), (2)not required operating pressure, and (3) low effects of high solute concentration of feed. However MD has fatal weakness which is not only very low flux, also membrane fouling. This study try to focus on MD fouling divided organic and inorganic and the way to control the foulants. The system was carried out under a different temperature of feed solution with various foulants. As basical experiment, it was observed that the increase in the mass flux of product solution is due to the increase in the temperature difference between the feed and product solution. Combind inorganic and organic fouling in membrane operations are still complex phenomena. It is necessary to develop MD process systematically for long term operation and management of the flux decline. Though previous studies, it was showed salt crystallization and heterogeneous nucleation mechanisms are affected by concentration polarization, electronic repulsion and Gibbs free energy. The idea of this experiment is to control inorganic and organic foulants respectively to simplified scaling mechnism and control foulants.