Nano filteration is a kind of technology between reverse osmosis and ulta filteration. The size of the surface hole is several nano meters. Its work principle is similar to physical screening but nanofiltration membrane is electrically charged. That is why it can work under small press. Desalination could be carried out too. Many fields such as electronics, food, medicines, fruit juice could use it. It could separate peptides and amino acids, carry out concentration and purification of antimicrobial cables, concentrate whey protein, combines Nano membrane and biochemical reactor.