Ultrafiltration membranes are capable of separating larger materials such as colloids, particulates, fats, bacteria, and proteins, while allowing sugars, and other low molecular weight molecules to pass through the membrane. Precise filtration hollow fiber membranes capable of filtering microparticles 0.02 - 0.2 μm in size from liquids. surface is coated with hydrophilic polyvinyl alcohol (PVA) so that less fouling occours, and as the lower end of hollow fibers is left free , suspended solids(SS) can be easily removed without accumulating between the fibers.