Conventional pre-treatment consisting of media filtration followed by cartridge filtration has been the preferred traditional system.

However this process suffers from the inevitable weight and size limitations imposed by large vessels plus significant operating costs from cartridge filter change-outs. In addition, as offshore systems are very susceptible to the annual summer bloom period, where concentrations of small organic particles and organisms increase exponentially, traditional filtration methods have been successful in reducing particles above 2 micron. This reduction is not sufficient to limit fouling on the sulphate reduction membranes.

Alternative mechanical type filters have recently been introduced to the market providing a smaller footprint, but still not addressing the sub 2-micron issue.

VWS Westgarth's Membrane filtration system provides an ideal platform for SRP pre-treatment.

The membranes used are chlorine resistant and the system design provides facility for the oxidation and removal of any organic species trapped on the membrane surface during filtration. The membrane provides a complete barrier against particles larger than approximately 0.1 microns, thereby removing most species that lead to SRP fouling and plant downtime due to membrane cleaning.

By providing this technology to installation operators, SRP cleaning downtime would be significantly reduced and pre-treatment integrity ensured.