Membrane manufacturers in India. Water filtration membranes are used for removing unwanted debris and particles from wastewater. Based on their different pore sizes and surface charge, water treatment membranes can perform various functions like mud-water separation, particle separation, brine separation, and ion separation processes. Membrane filtration is a pressure-driven technology with various pore sizes from 100 molecular weight to 5 microns. Membrane filtration is used commonly when particle filtration alone is not sufficient for water reuse. Three common types of membrane filtration processes are reverse osmosis, ultrafiltration, and microfiltration.