Ultra Filtration
The need for appropriate pre-treatment to ensure optimum performance of reverse osmosis (RO) systems is well understood. RO manufacturers always recommend certain inlet water parameters in order to ensure optimum performance and membrane life. Any deviance in the parameters causes serious downtimes and damage to production.
Conventional pre-treatment is not 100% secure to achieve this recommendation as well as other parameters recommended by RO manufacturers. Due to these limitations, membrane filtration and especially ultrafiltration (UF), is now started to be recognised to be the best pre-treatment before RO.
Ultrafiltration (UF) is theoretically the best pre-treatment before an RO system, removing from the feed water most of the potential elements responsible for membrane fouling such as particles, turbidity, bacteria and large molecular weight organic maters.
UF Benefits to RO Operation:
The UF acts as a barrier filter, retaining any particles over 0.1 micron. This allows the RO to operate at a higher design flux and therefore higher total flow, to increase production, or to produce the same flow as before but with less energy. In a new installation, a smaller RO can be used. With UF pre-treatment, the RO has reduced requirements for membrane cleaning, meaning that chemical usage and wastewater discharges are reduced. Longer membrane life is also a benefit.
