Performance of ultrafiltration and coagulation in an UF-RO seawater desalination demonstration plant

Transparent exopolymer particles (TEP) removal efficiency by a combination of coagulation and ultrafiltration to minimize SWRO membrane fouling

“…2.5 mg TOC/L BOM was added to seawater to mimic a high TEP concentration event. This TOC concentration was encountered in Oosterschelde area, South-Western of the Netherlands during high TEP events that coincided with very high fouling potential in UF systems (Schurer et al, 2012). The 2.5 mg TOC/L BOM contained 1.5 mg xanthan gum eq./L particulate and colloidal TEP (analyzed by alcian blue assay).…”

Seawater reverse osmosis desalination and (harmful) algal blooms

“…This scenario has been reported in recent studies (e.g., Villacorte et al, 2010a,b;Schurer et al, 2012;Qu et al, 2012a,b), signifying that AOM does not only cause pressure increase during filtration but can also increase non-backwashable or physically irreversible fouling in dead-end UF systems.…”

“…From published literature, inside-out UF membranes were reported to experience some degree of fouling during algal blooms (Schurer et al, 2012;. High concentrations of AOM present during a severe algal bloom in the North Sea impaired operation of UF membranes ( Figure 7) at a pilot desalination facility in the Netherlands, resulting in CEBs as frequent as once in 6…”

“…Under such conditions, coagulant was dosed to control hydraulic performance of UF membranes (Schurer et al, 2012;. With optimized inline coagulation, operation was stabilized at relatively low doses of ferric chloride (< 1 mg Fe/L) during the bloom period.…”

“…So far, a few studies have investigated the effect of algal blooms on operation of UF membranes (Kim and Yoon, 2005;Ladner et al, 2010;Schurer et al, 2012;Villacorte, 2014). These studies agree on the notion that large macromolecules (e.g., biopolymers such as polysaccharides and proteins)…”