Water Treatment Membrane Processes

Abstract

Membranes have emerged as a key means of water treatment in the 1990s and are likely to be the method of choice into the next century. A membrane or, more properly, a semipermeable membrane, is a thin layer of material that is capable of separating materials as a function of their physical and chemical properties when a driving force is applied across it. Membranes may be classified by the range of materials separated and the driving forces employed. For example, microfiltration (MF) and reverse osmosis (RO) are two membrane processes that use pressure to transport water across the membrane. MF membranes are capable of removing only particulate matter, while RO membranes retain many solutes as water permeates through the membrane. Electrodialysis is also capable of separating ionic solutes from water.