Ultrafiltration (UF) membrane filtration is a low pressure membrane process for water treatment that is designed to remove turbidity causing particles including those comprised of suspended solids, bacteria, colloidal matter and proteins.

The main separation mechanism of UF membrane filtration is size exclusion or sieving and the graphic illustrates that UF effectively removes particles in the size range of less than 0.01 to 0.1 mm. Effective removal of these contaminants in a source water results in a filtrate well suited for further treatment by downstream reverse osmosis.

The UF process is used in a wide variety of applications and industries and typical feed sources include seawater, surface, well and waste waters.