Ultrafiltration involves pressure driven separation of materials from feed. Pressure drives the process, typically operates with a feed pressure of 10 to 100 psi. UF plants are automated and have low operational manpower requirement. UF modules are available in tubular, hollow fiber, plate and frame and spiral configurations. UF membranes typically have pore sizes in the range of 0.01 to 0.1 microns. The smaller the nominal pore size, higher the removal efficiency. Materials used are polymeric and hydrophobic such as polysulfone (PS), polyether sulfone (PES) and polyvinylideneflouride (PVDF)
Ultrafiltration often used as a pre-treatment for reverse osmosis using surface water, seawater and biologically treated wastewater.