Water Filter Membrane

Ordinary water filters use a screen to separate particles from water streams. The holes that these Filters have are fairly large. This allows just about everything that is dissolved in the water to pass through as well. An RO drinking water treatment system employs a semi-permeable membrane. The membrane is a thin, multi-layered sheet with pores so small that water molecules can pass through, but it acts as a barrier to dissolved solids like salts and other chemicals. Thus even bacteria and viruses are trapped and not allowed to pass through.