Ultra-filtration (UF) is a type of membrane filtration in which hydrostatic pressure forces a liquid against a semipermeable membrane. A semipermeable membrane is a thin layer of material capable of separating substances when a driving force is applied across the membrane. Once considered a viable technology only for desalination, membrane processes are increasingly employed to remove bacteria and other microorganisms, particulate material, and natural organic material, which can impart color, tastes, and odors to the water and react with disinfectants to form disinfection byproducts (DBP). As advancements are made in membrane production and module design, capital and operating costs continue to decline . The ultrafiltration membrane only allows the solvent (such as water molecules), inorganic salts and small molecular organic substances in the solution to pass through, and the macromolecular substances such as suspended matter, colloid, protein and microorganisms in the solution are intercepted,thereby achieving the purpose of purification and separation in ultra filtration plant application.